Information on EC 1.10.3.1 - catechol oxidase

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The expected taxonomic range for this enzyme is: Eukaryota, Bacteria

EC NUMBER
COMMENTARY
1.10.3.1
-
RECOMMENDED NAME
GeneOntology No.
catechol oxidase
REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
2 catechol + O2 = 2 1,2-benzoquinone + 2 H2O
show the reaction diagram
-
-
-
-
2 catechol + O2 = 2 1,2-benzoquinone + 2 H2O
show the reaction diagram
catalytic reaction mechanism of the enzyme in a copper(II) complex with a macrocyclic ligand
-
2 catechol + O2 = 2 1,2-benzoquinone + 2 H2O
show the reaction diagram
the enzymes possesses a core carboxylate essential to activity, this enhanced catalytic efficiency of PPO
-
REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
oxidation
-
-
-
-
redox reaction
-
-
-
-
reduction
-
-
-
-
PATHWAY
BRENDA Link
KEGG Link
MetaCyc Link
Biosynthesis of secondary metabolites
-
-
esculetin biosynthesis
-
-
Isoquinoline alkaloid biosynthesis
-
-
Metabolic pathways
-
-
o-diquinones biosynthesis
-
-
Tyrosine metabolism
-
-
SYSTEMATIC NAME
IUBMB Comments
1,2-benzenediol:oxygen oxidoreductase
A type 3 copper protein that catalyses exclusively the oxidation of catechol (i.e., o-diphenol) to the corresponding o-quinone. The enzyme also acts on a variety of substituted catechols. It is different from tyrosinase, EC 1.14.18.1, which can catalyse both the monooxygenation of monophenols and the oxidation of catechols.
SYNONYMS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
1,2-benzene: oxygen oxidoreductase
-
-
1,2-benzenediol:oxygen oxidoreductase
P93622
-
AoCO4
Q2UNF9
-
catalase-phenol oxidase
-
bifunctional enzyme
catechol oxidase
-
-
catechol oxidase
Q2UNF9
-
catechol oxidase
-
-
catecholase
-
-
-
-
catecholase
-
mushroom tyrosinase shows catecholase and creolase activities
catecholase
-
-
catecholase
-
-
catecholase
-
-
catecholase
-
-
catecholase
-
-
catecholase
-
-
catecholase
-
-
catecholase
P93622
-
copper-S100B
-
-
cresolase
-
-
dihydroxy-L-phenylalanine:oxygen oxidoreductase
-
-
Diphenol oxidase
-
-
-
-
Diphenol oxidase
-
-
diphenolase
-
-
diphenolase
-
-
diphenolase
-
-
dopa oxidase
-
-
-
-
hemocyanin
-
behaves as a catecholoxidase and shows phenoloxidase activity in vitro
ibCO
-
sweet potato catechol oxidase
monophenol, o-diphenol: oxygen oxidoreductase
-
-
o-diphenol oxidoreductase
-
-
-
-
o-diphenol: dioxygen oxidoreductase, dehydrogenating
-
-
o-diphenol:oxygen oxidoreductase
-
-
-
-
o-diphenolase
-
-
-
-
o-diphenoloxidase
-
-
phenol oxidase
-
-
phenol oxidase
-
-
phenol oxidase
Mycelia sterilia
-
-
phenol oxidase
Mycelia sterilia IBR 35219/2
-
-
-
phenolase
-
-
-
-
phenoloxidase
-
-
phenoloxidase
-
-
phenoloxidase
-
-
phenoloxidase
-
-
polyphenol oxidase
-
-
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
A6N8J4, A6NAA0, A6YS04, A6YS05, C5MLZ1
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
Ferula sp.
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
-
-
polyphenol oxidase
P93622
-
polyphenoloxidase
-
-
polyphenoloxidase
-
-
PPO
A6N8J4, A6NAA0, A6YS04, A6YS05, C5MLZ1
-
PPO
Ferula sp.
-
-
PPO
-
from Coker 312, an embryogenic cultivar; from R405-2000, an nonembryogenic cultivar
PPO
-
-
PPO
-
-
PPO
P93622
-
PPO 1
-
isozyme
PPO 2
-
isozyme
PPO-6
I7HUF2
-
pyrocatechol oxidase
-
-
-
-
TYR3
-
isoform
tyrosinase
-
-
-
-
tyrosinase
-
-
tyrosinase
-
-
tyrosinase
-
-
monophenol, o-diphenol:oxygen oxidoreductase
-
-
additional information
-
cf. 1.14.18.1
additional information
-
cf. EC 1.14.18.1
additional information
-
cf. EC 1.14.18.1
additional information
-
cf. 1.14.18.1
additional information
-
cf. 1.14.18.1
additional information
-
cf. 1.14.18.1
additional information
-
cf. EC 1.14.18.1
additional information
-
cf. EC 1.14.18.1
additional information
-
cf. EC 1.14.18.1
additional information
-
cf. EC 1.14.18.1
CAS REGISTRY NUMBER
COMMENTARY
9002-10-2
not distinguished from EC 1.14.18.1
ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
strain A-2
-
-
Manually annotated by BRENDA team
Alternaria tenuis A-2
strain A-2
-
-
Manually annotated by BRENDA team
pawpaw fruit
-
-
Manually annotated by BRENDA team
red beet
-
-
Manually annotated by BRENDA team
spinach-beet
-
-
Manually annotated by BRENDA team
cultivar Longjing
UniProt
Manually annotated by BRENDA team
cultivar Puer
UniProt
Manually annotated by BRENDA team
cultivar Qihong
UniProt
Manually annotated by BRENDA team
cultivar Tieguanyin
UniProt
Manually annotated by BRENDA team
cultivar Xiangbolv
UniProt
Manually annotated by BRENDA team
cultivar Yihongzao
-
-
Manually annotated by BRENDA team
cv. Mundo Novo
-
-
Manually annotated by BRENDA team
cv. Conilon
-
-
Manually annotated by BRENDA team
Coffea guarini
-
-
-
Manually annotated by BRENDA team
two different varieties Cucumis melo L. cantalupensis cv. Charentais and Cucumis melo L. inodorus cv. Amarillo. Polyphenol oxidase (PPO) and peroxidase (POD) are extracted from two different varieties of melon
-
-
Manually annotated by BRENDA team
var. Gigante de Vranja, quince
-
-
Manually annotated by BRENDA team
cultivars Violetto di Provenza, Violetto di Sicilia, and Tema 2000
-
-
Manually annotated by BRENDA team
enzyme may be involved in photosynthesis, flower coloration and plant disease resistance
-
-
Manually annotated by BRENDA team
cv. Algerie
-
-
Manually annotated by BRENDA team
Ferula sp.
-
-
-
Manually annotated by BRENDA team
cv. Elsanta
-
-
Manually annotated by BRENDA team
sweet potato
-
-
Manually annotated by BRENDA team
variety Yate
-
-
Manually annotated by BRENDA team
cv. Bramleys seedling
-
-
Manually annotated by BRENDA team
Red delicious
-
-
Manually annotated by BRENDA team
Fuji apple
-
-
Manually annotated by BRENDA team
Mycelia sterilia
IBR 35219/2
-
-
Manually annotated by BRENDA team
Mycelia sterilia IBR 35219/2
IBR 35219/2
-
-
Manually annotated by BRENDA team
; polyphenol oxidase II, enzyme might act as an important defense system against the spread of pathogens at wounded sites
-
-
Manually annotated by BRENDA team
from different places in Turkey
-
-
Manually annotated by BRENDA team
spiny lobster
-
-
Manually annotated by BRENDA team
isoenzymes Ia, Ib and II
-
-
Manually annotated by BRENDA team
gene RSc0337
-
-
Manually annotated by BRENDA team
mediterranean slipper lobster
-
-
Manually annotated by BRENDA team
var. Naomi, Pizzutello, Rosa Maletto, and PO228, physicochemical properties of the different tomato varieties, overview
-
-
Manually annotated by BRENDA team
var. Jasim, purple-flesh potato
-
-
Manually annotated by BRENDA team
laccase-like secreted enzyme
-
-
Manually annotated by BRENDA team
PPO-6; gene ppo-6
UniProt
Manually annotated by BRENDA team
gene tyr2
-
-
Manually annotated by BRENDA team
two isozymes
-
-
Manually annotated by BRENDA team
cultivar Grenache
UniProt
Manually annotated by BRENDA team
ssp. satiVa, var. Victoria
-
-
Manually annotated by BRENDA team
sultana grape
SwissProt
Manually annotated by BRENDA team
GENERAL INFORMATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
physiological function
-
polyphenol oxidases are induced in cowpea plants by wounding
physiological function
-
cold-adapted hemocyanin-derived phenoloxidase activity is important to the survival of Erimacrus isenbeckii at low temperature (4C)
physiological function
-
phenoloxidase functions as a catalytic enzyme in melanin production in ink sacs and also as a humoral factor in host defense via melaninization
physiological function
Q2UNF9
catechol oxidases catalyse the oxidation of different para-substituted o-diphenols, showing diphenolase activity
physiological function
-
the enzyme is essential for Clonorchis sinensis reproduction
evolution
Q2UNF9
AoCO4 belongs to the short-tyrosinase family. The catalytic differences to the phenolases, EC 1.14.18.1, are not due to structural features
additional information
I7HUF2
modeling of the three-dimensional structure of the PPO-6 tyrosinase domain
additional information
Q2UNF9
overall and active site structure analysis, catalytic binuclear centre, overview. The enzyme dimerisation does not have a clear functional role
SUBSTRATE
PRODUCT                      
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
LITERATURE
(Substrate)
COMMENTARY
(Product)
LITERATURE
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
(+)-catechin + O2
?
show the reaction diagram
-
-
-
-
?
(+)-catechin + O2
?
show the reaction diagram
-
-
-
-
?
(+)-catechin + O2
?
show the reaction diagram
Ferula sp.
-
-
-
-
?
(+)-catechin hydrate + O2
?
show the reaction diagram
-
-
-
-
?
(-)-catechin + O2
?
show the reaction diagram
-
enzyme activity relative to 4-methylcatechol: 0.77%
-
-
?
(-)-epicatechin + O2
?
show the reaction diagram
-
-
-
-
?
(-)-epicatechin + O2
?
show the reaction diagram
-
-
-
-
?
(-)-epicatechin + O2
?
show the reaction diagram
Ferula sp.
-
high activity
-
-
?
(-)-epigallocatechin + O2
?
show the reaction diagram
Camellia sinensis, Mycelia sterilia, Mycelia sterilia IBR 35219/2
-
-
-
-
?
(-)-epigallocatechin gallate + O2
?
show the reaction diagram
Camellia sinensis, Mycelia sterilia, Mycelia sterilia IBR 35219/2
-
-
-
-
?
(R)-dopaxanthin + dehydroascorbic acid + O2
(R)-dopaxanthin quinone + L-ascorbic acid + H2O
show the reaction diagram
-
(R)-dopaxanthin is a pigment, the reaction rate on the (R)-isomer of dopaxanthin is 1.9fold lower than that for the (S)-isomer
quantitative product analysis
-
?
(R)-tyrosine-betaxanthin + L-DOPA + O2
(R)-dopaxanthin + dopaquinone + H2O
show the reaction diagram
-
i.e. (R)-portulacaxanthin II, the activity of the enzyme is not restricted to betaxanthins derived from (S)-amino acids
( R)-dopaxanthin is a pigment, quantitative product analysis
-
?
1-butylcatechol + O2
?
show the reaction diagram
-
-
-
-
?
1-tert-butyl-catechol + O2
?
show the reaction diagram
-
-
-
-
?
2 4-methylcatechol + O2
2 4-methyl-1,2-benzoquinone + 2 H2O
show the reaction diagram
-
-
-
-
?
2 4-methylcatechol + O2
2 4-methyl-1,2-benzoquinone + 2 H2O
show the reaction diagram
I7HUF2
-
-
-
?
2 catechol + O2
2 1,2-benzoquinone + 2 H2O
show the reaction diagram
-
-
-
-
?
2 catechol + O2
2 1,2-benzoquinone + 2 H2O
show the reaction diagram
-
-
-
-
?
2 catechol + O2
2 1,2-benzoquinone + 2 H2O
show the reaction diagram
-
-
-
-
?
2 catechol + O2
2 1,2-benzoquinone + 2 H2O
show the reaction diagram
-
enzyme activity relative to 4-methylcatechol: 87%
-
-
?
2 dopamine + O2
2 4-(2-aminoethyl)-1,2-benzoquinone + 2 H2O
show the reaction diagram
-
-
-
-
?
2 dopamine + O2
2 4-(2-aminoethyl)-1,2-benzoquinone + 2 H2O
show the reaction diagram
-
dopamine is the most specific substrate
-
-
?
2 o-diphenol + O2
2 o-quinone + 2 H2O
show the reaction diagram
I7HUF2
the reaction depends on molecular oxygen, which is reduced by the copper-containing catalytic domain of the enzyme
-
-
?
2,3,4-trihydroxybenzoic acid + O2
?
show the reaction diagram
Q9ZP19
-
-
-
?
2,3,4-trihydroxybenzoic acid + O2
?
show the reaction diagram
-
-
-
-
?
2,3-dihydroxybenzoic acid + O2
?
show the reaction diagram
-
-
-
-
?
2-methylhydroquinone + O2
?
show the reaction diagram
-
low activity
-
-
?
3,4,5-trihydroxy-L-phenylalanine + O2
?
show the reaction diagram
-
cytotoxicity of TOPA, i.e. TOPA
-
-
?
3,4,5-trihydroxybenzoic acid + O2
?
show the reaction diagram
-
isoenzymes A-C, trivial name gallic acid
-
-
?
3,4,5-trihydroxybenzoic acid + O2
?
show the reaction diagram
-
trivial name gallic acid
-
-
?
3,4-dihydroxyhydrocinnamic acid + O2
?
show the reaction diagram
-
-
-
-
?
3,4-dihydroxyphenyl acetic acid + O2
?
show the reaction diagram
-
-
-
-
?
3,4-dihydroxyphenyl propionic acid + O2
?
show the reaction diagram
-
-
-
-
?
3,4-dihydroxyphenylacetic acid + O2
?
show the reaction diagram
-
-
-
-
?
3,4-dihydroxyphenylacetic acid + O2
(3,4-dioxocyclohexa-1,5-dien-1-yl)acetic acid + H2O
show the reaction diagram
-
-
-
-
?
3,4-dihydroxyphenylacetic acid + O2
(3,4-dioxocyclohexa-1,5-dien-1-yl)acetic acid + H2O
show the reaction diagram
Q9ZP19
-
-
-
?
3,4-dihydroxyphenylacetic acid + O2
(3,4-dioxocyclohexa-1,5-dien-1-yl)acetic acid + H2O
show the reaction diagram
-
-
-
-
?
3,5-di-tert-butylcatechol + O2
3,5-di-tert-butyl-o-benzoquinone + H2O
show the reaction diagram
-
mechanism, the rate-determining step is found to change with the substrate to complex ratio, I2+ reacts with DTBCH2, while undergoing a one-electron reduction, leading to the formation of mixed-valence CuIICuIsemiquinone species DTSQ
-
-
?
3-(3,4-dihydroxyphenyl)-L-alanine + O2
?
show the reaction diagram
-
enzyme activity relative to 4-methylcatechol: 1.15%
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone
show the reaction diagram
Q9ZP19
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone
show the reaction diagram
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone
show the reaction diagram
-
140% of activity with catechol
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone
show the reaction diagram
-
field bean PPO obeys Michaelis-Menten kinetics and exhibits the phenomenon of inhibition by excess substrate for catechol, 4-methylcatechol and 4-tert-butylcatechol
-
-
?
4-methylcatechol + O2
4-methyl-o-benzoquinone
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
4-methyl-o-benzoquinone
show the reaction diagram
-
-
-
?
4-methylcatechol + O2
4-methyl-o-benzoquinone
show the reaction diagram
-
isoenzymes A-D
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
Ferula sp.
-
-
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
208% activity with 10 mM substrate concentration compared to catechol
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
-
highest level of enzyme activity in cultivar Violetto di Provenza
-
-
?
4-methylcatechol + O2
?
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
?
show the reaction diagram
-
-
-
-
?
4-methylcatechol + O2
?
show the reaction diagram
-
highest activity
-
-
?
4-methylcatechol + O2
?
show the reaction diagram
-
enzyme shows high affinity to this substrate
-
-
?
4-methylcatechol + O2
?
show the reaction diagram
-
enzyme shows highest activity with 4-methylcatechol
-
-
?
4-methylcatechol + O2
?
show the reaction diagram
-
enzyme shows highest affinity to this substrate
-
-
?
4-O-caffeoylquinic acid + O2
?
show the reaction diagram
-
-
-
-
?
4-tert-butylcatechol + O2
4-tert-butyl-1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
4-tert-butylcatechol + O2
4-tert-butyl-1,2-benzoquinone + H2O
show the reaction diagram
Q9ZP19
-
-
-
?
4-tert-butylcatechol + O2
4-tert-butyl-1,2-benzoquinone + H2O
show the reaction diagram
P93622
-
-
-
?
4-tert-butylcatechol + O2
?
show the reaction diagram
-
-
-
-
?
4-tert-butylcatechol + O2
?
show the reaction diagram
-
field bean PPO obeys Michaelis-Menten kinetics and exhibits the phenomenon of inhibition by excess substrate for catechol, 4-methylcatechol and 4-tert-butylcatechol
-
-
?
4-[(4-methylbenzol)azo]-1,2-benzenediol + O2
?
show the reaction diagram
-
-
-
-
?
5-caffeoyl quinic acid + O2
?
show the reaction diagram
-
i.e. chlorogenic acid
-
-
?
aminophenol + O2
?
show the reaction diagram
-
-
-
-
?
aniline + O2
?
show the reaction diagram
-
enzyme shows also activity after 24 h incubation
-
-
?
betanidin + O2
betanidin-quinone + H2O
show the reaction diagram
-
the structural unit of the violet betacyanins from Lampranthus productus flowers, the reacion is reversible by ascorbic acid addition at pH 5.0 and 4C
-
-
?
caffeic acid + 1/2 O2
caffeoyl quinone + H2O
show the reaction diagram
-
-
-
?
caffeic acid + 1/2 O2
caffeoyl quinone + H2O
show the reaction diagram
-
-
-
?
caffeic acid + 1/2 O2
caffeoyl quinone + H2O
show the reaction diagram
-
isoenzymes C and D
-
?
caffeic acid + 1/2 O2
caffeoyl quinone + H2O
show the reaction diagram
-
2% of activity with dopamine
-
-
?
caffeic acid + O2
?
show the reaction diagram
-
-
-
-
?
caffeic acid + O2
?
show the reaction diagram
-
-
-
-
?
caffeic acid + O2
?
show the reaction diagram
-
-
-
-
?
caffeic acid + O2
?
show the reaction diagram
-
-
-
-
?
caffeic acid + O2
?
show the reaction diagram
-
-
-
-
?
caffeic acid + O2
caffeoyl quinone + H2O
show the reaction diagram
-
-
-
-
?
caffeic acid + O2
caffeoyl quinone + H2O
show the reaction diagram
-
-
-
-
?
catechin + O2
?
show the reaction diagram
-
-
-
-
?
catechin + O2
?
show the reaction diagram
-
-
-
-
?
catechin + O2
?
show the reaction diagram
Mycelia sterilia
-
-
-
-
?
catechin + O2
?
show the reaction diagram
Ferula sp.
-
-
-
-
?
catechin + O2
?
show the reaction diagram
-
enzyme shows moderate affinity to this substrate
-
-
?
catechin + O2
?
show the reaction diagram
Mycelia sterilia IBR 35219/2
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
-
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
Mycelia sterilia
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
Ferula sp.
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
Ferula sp.
-
best substrate
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
low activity
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
preferred substrate
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
no activity with tyrosine, o-methoxyphenol, p-catechol and m-catechol
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
no activity with phenol, 4-cresol, L-tyrosine and 4-coumaric acid
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
peel enzyme, 34% of activity with dopamine
-
-
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
isoenzymes A, B, C and D show no phenolase activity
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
isoenzymes Ia, Ib and II, 90, 43 and 42% of activity with L-dopa respectively, no activity with L-tyrosine, D-tyrosine, hydroquinone and methylhydroquinone
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
no activity with tyrosine, 2-methoxyphenol, 4-hydroxy-3-methoxy-cinnamic acid, hydroquinone and rutin
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
pulp enzyme, 54% of activity with dopamine
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
Mycelia sterilia IBR 35219/2
-
-
-
-
?
catechol + O2
?
show the reaction diagram
-
-
-
-
?
catechol + O2
?
show the reaction diagram
-
-
-
-
?
catechol + O2
?
show the reaction diagram
-
best substrate
-
-
?
catechol + O2
?
show the reaction diagram
-
weak substrate
-
-
?
catechol + O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + O2
1,2-benzoquinone + H2O
show the reaction diagram
Q9ZP19
-
-
-
?
catechol + O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + O2
1,2-benzoquinone + H2O
show the reaction diagram
P93622
-
-
-
?
catechol + O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + O2
1,2-benzoquinone + H2O
show the reaction diagram
A6N8J4, A6NAA0, A6YS04, A6YS05, C5MLZ1
-
-
-
?
catechol + O2
1,2-benzoquinone + H2O
show the reaction diagram
-
field bean PPO obeys Michaelis-Menten kinetics and exhibits the phenomenon of inhibition by excess substrate for catechol, 4-methylcatechol and 4-tert-butylcatechol
-
-
?
catechol + O2
1,2-benzoquinone + H2O
show the reaction diagram
-
the highest oxidase activity is observed against catechol
-
-
?
catechol + O2
1,2-benzoquinone + H2O
show the reaction diagram
-
enzyme shows high affinity to this substrate, enzyme shows highest affinity to this substrate
-
-
?
catechol + O2
1,2-benzoquinone + H2O
show the reaction diagram
-
100% activity with 10 mM substrate concentration
-
-
?
catechol + O2
o-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
-
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
-
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
-
-
-
-
chlorogenic acid + O2
?
show the reaction diagram
-
-
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
-
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
-
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
-
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
Ferula sp.
-
-
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
preferred substrate
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
isoenzymes A-D
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
50% of activity with catechol
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
peel enzyme, 5.3% of activity with dopamine
-
-
-
chlorogenic acid + O2
?
show the reaction diagram
-
pulp enzyme, 24.5% of activity with dopamine
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
best substrate for both leaf and endosperm enzyme, probably the major substrate in vivo
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
formation of a highly reactive o-quinone intermediate which then could interact with NH2 groups of lysine, SCH3 groups of methionines and indole rings of tryptophan in nucleophilic addition and in polymerization reactions, the so-called browning and greening reactions, formation of a highly reactive o-quinone intermediate
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
preferred substrate, 50fold faster reaction rate with the particulate, latent enzyme form compared to the soluble active enzyme
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
enzyme activity relative to 4-methylcatechol: 6.15%
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
highest level of enzyme activity in cultivars Tema 2000 and Violetto di Sicilia
-
-
?
coumaric acid + O2
?
show the reaction diagram
-
-
-
-
?
cumaric acid + O2
?
show the reaction diagram
-
-
-
-
?
D-catechin + O2
?
show the reaction diagram
-
-
-
-
?
D-catechin + O2
?
show the reaction diagram
-
-
-
-
?
D-catechin + O2
?
show the reaction diagram
-
best substrate
-
-
?
D-catechin + O2
?
show the reaction diagram
-
pulp enzyme, 35.6% of activity with dopamine
-
-
?
D-catechin + O2
?
show the reaction diagram
-
peel enzyme, 11.5% of activity with dopamine
-
-
-
D-catechin + O2
?
show the reaction diagram
-
isoenzymes A-D
-
-
?
D-dopa + 1/2 O2
D-dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
D-dopa + 1/2 O2
D-dopaquinone + H2O
show the reaction diagram
-
-
-
-
-
D-dopa + 1/2 O2
D-dopaquinone + H2O
show the reaction diagram
-
isoenzymes Ia, Ib and II, 54, 60 and 48% of activity with L-dopa respectively
-
?
dicatechol + O2
?
show the reaction diagram
-
-
-
-
?
dicatechol + O2
?
show the reaction diagram
-
-
-
-
?
dicatechol + O2
?
show the reaction diagram
-
-
-
-
?
digallol + O2
?
show the reaction diagram
-
-
-
-
?
digallol + O2
?
show the reaction diagram
-
-
-
-
?
digallol + O2
?
show the reaction diagram
-
low activity
-
-
?
digallol + O2
?
show the reaction diagram
Ferula sp.
-
low activity
-
-
?
dihydrocaffeic acid + O2
?
show the reaction diagram
-
-
-
-
?
dihydroxyphenylalanine + O2
dihydroxyphenylalanine quinone + H2O
show the reaction diagram
-
-
-
-
?
DL-2-methyl-3,4-dihydroxyphenylalanine + O2
2-methyldopaquinone + H2O
show the reaction diagram
-
the L-isomer is preferred
-
-
?
DL-DOPA + O2
dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
DL-DOPA + O2
dopaquinone + H2O
show the reaction diagram
-
i.e. DL-3,4-dihydroxyphenylalanine, the L-isomer is preferred
-
-
?
DL-isoproterenol + O2
?
show the reaction diagram
-
the L-isomer is preferred
-
-
?
DL-isoproterenol + O2
?
show the reaction diagram
-
the L-isomer is preferred
-
-
?
dopamine + 1/2 O2
dopamine quinone + H2O
show the reaction diagram
-
-
-
-
?
dopamine + O2
4-(2-aminoethyl)-1,2-benzoquinone + 2 H2O
show the reaction diagram
-
-
-
-
dopamine + O2
4-(2-aminoethyl)-1,2-benzoquinone + 2 H2O
show the reaction diagram
-
-
-
?
dopamine + O2
4-(2-aminoethyl)-1,2-benzoquinone + 2 H2O
show the reaction diagram
-
-
-
?
dopamine + O2
4-(2-aminoethyl)-1,2-benzoquinone + 2 H2O
show the reaction diagram
-
isoenzymes A-D
-
?
dopamine + O2
?
show the reaction diagram
-
-
-
-
-
dopamine + O2
?
show the reaction diagram
-
-
-
-
?
dopamine + O2
?
show the reaction diagram
-
-
-
-
?
dopamine + O2
?
show the reaction diagram
-
-
-
-
?
dopamine + O2
?
show the reaction diagram
-
-
-
-
?
dopamine + O2
?
show the reaction diagram
-
-
-
-
?
dopamine + O2
?
show the reaction diagram
-
-
-
-
?
dopamine + O2
?
show the reaction diagram
Ferula sp.
-
low activity
-
-
?
dopamine + O2
?
show the reaction diagram
-
enzyme shows moderate affinity to this substrate
-
-
?
dopamine + O2
dopaminequinone + H2O
show the reaction diagram
-
-
-
-
?
epicatechin + O2
?
show the reaction diagram
-
-
-
-
?
epicatechin + O2
?
show the reaction diagram
-
peel enzyme, 9.3% of activity with dopamine
-
-
-
epicatechin + O2
?
show the reaction diagram
-
pulp enzyme, 22.7% of activity with dopamine
-
-
?
epinephrine + O2
?
show the reaction diagram
-
-
-
-
?
epinephrine + O2
?
show the reaction diagram
-
-
-
-
?
ferulic acid + O2
?
show the reaction diagram
-
-
-
-
?
gallic acid + O2
?
show the reaction diagram
Ferula sp.
-
low activity
-
-
?
gallic acid + O2
?
show the reaction diagram
-
enzyme shows very low affinity to this substrate
-
-
?
guaiacol + O2
?
show the reaction diagram
-
-
-
-
?
hydroquinone + O2
?
show the reaction diagram
-
low activity
-
-
?
hydroxyquinone + O2
?
show the reaction diagram
-
-
-
-
?
L-3,4-dihydroxyphenylalanine methyl ester + 1/2 O2
L-dopaquinone methyl ester + H2O
show the reaction diagram
-
-
-
-
?
L-adrenaline + O2
?
show the reaction diagram
-
-
-
-
?
L-catechin + O2
?
show the reaction diagram
-
-
-
-
?
L-dihydroxyphenylalanine + O2
L-dopaquinone + H2O
show the reaction diagram
-
L-dopa
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
isoenzymes A-D
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
22.65 of activity with catechol
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
peel enzyme, 8.0% of activity with dopamine
-
-
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
no activity with tyrosine, p-methoxyphenol and catechol
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
pulp enzyme, 12.3% of activity with dopamine
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
endosperm enzyme, 3.9% of activity with chlorogenic acid
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
i.e. L-3,4-dihydroxyphenylalanine
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
i.e. L-3,4-dihydroxyphenylalanine
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
i.e. L-3,4-dihydroxyphenylalanine
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
i.e. L-3,4-dihydroxyphenylalanine
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
i.e. L-3,4-dihydroxyphenylalanine, low activity
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
low activity with the D-isomer, 18% of the activity with the L-isomer
-
-
?
L-dopa + O2
dopachrome + H2O
show the reaction diagram
-
-
-
-
?
L-dopa + O2
dopachrome + H2O
show the reaction diagram
-
-
-
-
?
L-DOPA + O2
?
show the reaction diagram
-
-
-
-
?
L-DOPA + O2
?
show the reaction diagram
-
-
-
-
?
L-DOPA + O2
?
show the reaction diagram
-
-
-
-
?
L-DOPA + O2
?
show the reaction diagram
Ferula sp.
-
low activity
-
-
?
L-DOPA + O2
dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-Dopa + O2
L-dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-Dopa + O2
L-dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-Dopa + O2
L-dopaquinone + H2O
show the reaction diagram
-
specific substrate
-
-
?
L-noradrenaline + O2
?
show the reaction diagram
-
-
-
-
?
L-tyrosine + L-dopa + O2
L-dopa + dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-tyrosine + L-dopa + O2
L-dopa + dopaquinone + H2O
show the reaction diagram
-
-
-
-
-
L-tyrosine + L-dopa + O2
L-dopa + dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-tyrosine + L-dopa + O2
L-dopa + dopaquinone + H2O
show the reaction diagram
-
-
-
-
-
L-tyrosine + L-dopa + O2
L-dopa + dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-tyrosine + L-dopa + O2
L-dopa + dopaquinone + H2O
show the reaction diagram
-
-
o-dopaquinone is unstable in aqueous solution and rapidly suffers a non-enzymatic cyclization to leukodopachrome
-
?
L-tyrosine + L-dopa + O2
L-dopa + dopaquinone + H2O
show the reaction diagram
-
pathway of melanin biosynthesis, detailed overview
cytotoxicity of L-DOPA
-
?
L-tyrosine + O2
dihydroxyphenylalanine + H2O
show the reaction diagram
-
-
-
-
?
myricetin + O2
?
show the reaction diagram
-
-
-
-
?
N-acetyldopamine + O2
?
show the reaction diagram
-
NADA
-
-
?
Norepinephrine + O2
?
show the reaction diagram
-
-
-
-
?
p-cresol + O2
?
show the reaction diagram
-
enzyme shows also activity after 24 h incubation
-
-
?
p-hydroquinone + O2
?
show the reaction diagram
-
-
-
-
?
phenol + O2
?
show the reaction diagram
-
enzyme shows also activity after 24 h incubation
-
-
?
phloroglucinol + O2
?
show the reaction diagram
-
-
-
-
?
protocatechuic acid + O2
?
show the reaction diagram
-
-
-
-
?
protocatechuic acid + O2
?
show the reaction diagram
-
isoenzyme C
-
-
?
pyrogallic acid + O2
?
show the reaction diagram
-
-
-
-
?
pyrogallol + O2
?
show the reaction diagram
-
-
-
-
?
pyrogallol + O2
?
show the reaction diagram
-
-
-
-
?
pyrogallol + O2
?
show the reaction diagram
-
-
-
-
?
pyrogallol + O2
?
show the reaction diagram
-
-
-
-
?
pyrogallol + O2
?
show the reaction diagram
-
-
-
-
?
pyrogallol + O2
?
show the reaction diagram
-
-
-
-
?
pyrogallol + O2
?
show the reaction diagram
-
-
-
-
?
pyrogallol + O2
?
show the reaction diagram
Mycelia sterilia
-
-
-
-
?
pyrogallol + O2
?
show the reaction diagram
-
-
-
-
?
pyrogallol + O2
?
show the reaction diagram
-
pulp enzyme, 5.5% of activity with dopamine
-
-
?
pyrogallol + O2
?
show the reaction diagram
-
isoenzymes Ia, Ib and II, 5, 8 and 15% of activity with L-dopa respectively
-
-
?
pyrogallol + O2
?
show the reaction diagram
-
24% of activity with catechol
-
-
?
pyrogallol + O2
?
show the reaction diagram
-
peel enzyme, 1.4% of activity with dopamine
-
-
-
pyrogallol + O2
?
show the reaction diagram
-
enzyme activity relative to 4-methylcatechol: 9.24%
-
-
?
pyrogallol + O2
?
show the reaction diagram
-
enzyme shows low affinity to this substrate
-
-
?
pyrogallol + O2
?
show the reaction diagram
-
746% activity with 10 mM substrate concentration compared to catechol
-
-
?
pyrogallol + O2
?
show the reaction diagram
Mycelia sterilia IBR 35219/2
-
-
-
-
?
quercetin + O2
?
show the reaction diagram
-
-
-
-
?
quercetin + O2
?
show the reaction diagram
-
-
-
-
?
rosmarinic acid + O2
?
show the reaction diagram
-
-
-
-
?
rutin + O2
?
show the reaction diagram
-
-
-
-
?
shikimic acid + O2
?
show the reaction diagram
-
-
-
-
?
tannic acid + O2
?
show the reaction diagram
-
-
-
-
?
tert-butyl-catechol + O2
?
show the reaction diagram
-
2fold faster reaction rate with the particulate, latent enzyme form compared to the soluble active enzyme
-
-
?
tert-butylcatechol + O2
?
show the reaction diagram
-
-
-
-
?
tetramethylbenzidine + O2
?
show the reaction diagram
-
enzyme shows low affinity to this substrate
-
-
?
tyrosol + O2
?
show the reaction diagram
-
enzyme shows also activity after 24 h incubation
-
-
?
verbascosid + O2
?
show the reaction diagram
-
-
-
-
?
Luteolin-7-glycoside + O2
?
show the reaction diagram
-
-
-
-
?
additional information
?
-
-
extremely low levels of activity suggest that this protein likely plays no direct metabolic role in the biodegradation of catecholamines
-
-
-
additional information
?
-
-
PPO II inhibits cultures of Escherichia coli and it accumulates on the wounded sites of tobacco leaves indicating that it may act as a defense role in plat defense system
-
-
-
additional information
?
-
-
the enzyme catalyzes the oxidation of o-phenolic substrates to o-quinones, which are subsequently polymerized to dark-coloured pigments. Polyphenoloxidase is considered to be the main contributor to browning discolouration and darkening in fruits and vegetables
-
-
-
additional information
?
-
-
no activity detected with L-Tyr, resorcinol and p-cresol
-
-
-
additional information
?
-
-
no activity towards the monophenols p-cresol or L-Tyr
-
-
-
additional information
?
-
-
no activity with p-cresol or L-Tyr
-
-
-
additional information
?
-
-
no activity with tyrosine, o-methoxyphenol, p-diphenol and m-diphenol
-
-
-
additional information
?
-
-
expressionlevels of polyphenol oxidase activity exhibiting enzymes in the organism, overview
-
-
-
additional information
?
-
-
mechanical damage by Hemileia vastatrix fungus, the causal agent of the leaf orange rust disease, inoculation and Leucoptera coffeella, the coffee leaf miner, infestation caused different responses in PPO activity in different Coffea species, level of damage or resistance, overview
-
-
-
additional information
?
-
Ferula sp.
-
polyphenol oxidase is a major enzyme responsible for the browning reaction in damaged plant tissues and fruits
-
-
-
additional information
?
-
-
PPO activity increases in the transition from the vegetative stage to the generative stage
-
-
-
additional information
?
-
-
PPO activity is associated with color changes associated with browning and lycopene degradation, the commercial variety Naomi is more susceptible to enzymatic browning than the local varieties Pizzutello, Rosa Maletto and PO228, due to higher PPO activity levels, lycopene is an antioxidant agent that reconstitutes the polyphenols oxidized by the action of PPO
-
-
-
additional information
?
-
-
PPO oxidizes o-diphenolic compounds to the corresponding o-quinones in the presence of oxygen, subsequently the o-quinones polymerize with other o-quinones, proteins, amino acids etc., resulting in the formation of brown complexes, the enzyme is one of the main enzymes responsible for quality loss in strawberry taste due to phenolic degradation
-
-
-
additional information
?
-
-
role of the enzyme in the biosynthetic scheme of betalains, overview
-
-
-
additional information
?
-
-
the enzyme is considered as defence oxidative enzyme, is vital the physiological defence strategy adapted by plants to insect herbivory and pathogen attack
-
-
-
additional information
?
-
-
the enzyme plays a role in enzymatic browning, rapid discolouration of leaf, stem and root tissue after injury and strong pigmentation of tissue extracts, PPO and phenolic compounds could be an important part of the plants defence system against pests and diseases, including root parasitic nematodes, e.g. Radopholus similis
-
-
-
additional information
?
-
-
tyrosinase is known to be a key enzyme in melanin biosynthesis, involved in determining the color of mammalian skin and hair, various dermatological disorders, such as melasma, age spots and sites of actinic damage, arise from the accumulation of an excessive level of epidermal pigmentation
-
-
-
additional information
?
-
-
betanidin is a labile compound, overview
-
-
-
additional information
?
-
-
broad substrate specificity, overview, tyrosinase is a mono-oxygenase and a bifunctional enzyme that catalyzes the o-hydroxylation of monophenols and subsequent oxidation of o-diphenols to quinones, the enzyme thus accepts monophenols and diphenols as substrates, and the monophenolase activity is the initial rate-determining reaction
-
-
-
additional information
?
-
-
multifunctional enzyme
-
-
-
additional information
?
-
-
oxidation of this and other o-diphenols to o-quinones
-
-
-
additional information
?
-
-
PPO oxidizes o-diphenolic compounds to the corresponding o-quinones in the presence of oxygen
-
-
-
additional information
?
-
-
reduction of dioxygen to dihydrogen peroxide upon catechol oxidation by copper(II) complexes, overview, dioxygen undergoes a two-electron reduction to dihydrogen peroxide, and a second mechanism in which it is converted into water upon four-electron reduction, catecholase activity of a tetranuclear carbonato-bridged copper(II) cluster with the macrocyclic ligand 9,22-dipropyl-1,4,9,14,17,22,27,28,29,30-decaazapentacyclotriacontane-5,7(28),11(29),12,18,20(30),24(27),25-octaene, ferromagnetic interaction between the two copper ions within one macrocyclic ring, and a weak antiferromagnetic interaction between the two neighboring copper ions of two different macrocyclic units, solution stability, electrochemical properties, and crystal structure of (I)2(CF3SO3)4 - 2CH3CN- 4H2O, detailed overview, mechanisms versus a coordination mode of the substrate
-
-
-
additional information
?
-
-
stereospecificity, and monophenolase and diphenolase activities and specificities dependent on conditions, overview
-
-
-
additional information
?
-
-
substrate specificity of the purified enzyme, overview, highest PPO activity occurs with 4-methylcatechol, followed by catechol, pyrogallol, (-)-epicatechin, caffeic acid, and DL-dopa, little or no activity is detected toward the monophenolic compounds ferulic acid, L-tyrosine, and phenol
-
-
-
additional information
?
-
-
substrate specificity of the soluble and particulate enzyme forms, overview
-
-
-
additional information
?
-
-
substrate specificity, overview, activity with phenolic and diphenolic substrates, also performing the reaction of tyrosinase, a ortho-hydroxylation of monophenols, EC 1.14.18.1, and the oxidation of catechols to ortho-quinones, the diphenolase activity, EC 1.10.3.1, overview
-
-
-
additional information
?
-
-
substrate specificity, overview, no activity with hydroquinic acid, resorcinol, and tyrosine
-
-
-
additional information
?
-
Ferula sp.
-
substrate specificity, overview, no activity with L-tyrosine
-
-
-
additional information
?
-
-
substrate specificity, overview, the enzyme catalyzes the hydroxylation of monophenols to o-diphenols, monophenolase activity EC 1.14.18.1, and the oxidation of the o-diphenols to o-quinones, diphenolase activity EC 1.10.3.1, cross-reaction analysis, overview
-
-
-
additional information
?
-
-
the enzyme catalyses two different reactions, each using molecular oxygen: the hydroxylation of monophenols to o-diphenols, monophenolase activity, and the oxidation of o-diphenols to o-quinones, diphenolase, overview
-
-
-
additional information
?
-
-
the enzyme catalyzes the hydroxylation of monophenols to o-diphenols, monophenolase activity EC 1.14.18.1, and the oxidation of the o-diphenols to o-quinones, diphenolase activity EC 1.10.3.1, cross-reaction analysis, overview
-
-
-
additional information
?
-
-
the enzyme catalyzes the hydroxylation of monophenols to o-diphenols, monophenolase activity EC 1.14.18.1, and the oxidation of the o-diphenols to o-quinones, diphenolase activity EC 1.10.3.1, cross-reaction analysis, overview
-
-
-
additional information
?
-
-
the enzyme catalyzes the hydroxylation of monophenols to o-diphenols, monophenolase activity EC 1.14.18.1, and the oxidation of the o-diphenols to o-quinones, diphenolase activity EC 1.10.3.1, cross-reaction analysis, overview
-
-
-
additional information
?
-
-
the enzyme catalyzes the hydroxylation of monophenols to o-diphenols, monophenolase activity EC 1.14.18.1, and the oxidation of the o-diphenols to o-quinones, diphenolase activity EC 1.10.3.1, cross-reaction analysis, overview
-
-
-
additional information
?
-
-
the enzyme catalyzes the hydroxylation of monophenols to o-diphenols, monophenolase activity EC 1.14.18.1, and the oxidation of the o-diphenols to o-quinones, diphenolase activity EC 1.10.3.1, cross-reaction analysis, overview
-
-
-
additional information
?
-
-
the enzyme shows catecholase and cresolase activities, a type III copper protein that catalyses the O-hydroxylation of monophenols and oxidation of O-diphenols using molecular oxygen
-
-
-
additional information
?
-
-
the purified tyrosinase from hemolymph shows both monophenolase, EC 1.14.18.1, and diphenolase, EC 1.10.3.1, activity and therefore it can be defined as a true tyrosinase, the purified hemocynin does not show any tyrosinase activity
-
-
-
additional information
?
-
-
tyrosinase is a copper-containing enzyme that catalyzes two distinct reactions of melanin synthesis: the hydroxylation of tyrosine by monophenolase action and the oxidation of 3,4-dihydroxyphenylalanine (L-DOPA) to o-dopaquinone by diphenolase action
-
-
-
additional information
?
-
Q9ZP19
pyragallol is not oxidized by ibCO
-
-
-
additional information
?
-
-
to investigate the substrate specificity of activated hemocyanin, the turnover of several diphenols is compared using an oxygen electrode
-
-
-
additional information
?
-
-
no activity is detected against L-tyrosine and common laccase substrates such as 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) and syringaldazine with the exception of weak activity with p-hydroquinone
-
-
-
additional information
?
-
-
no activity with L-tyrosine
-
-
-
additional information
?
-
-
phenoloxidase activity is not observed when tyramine and tyrosine (monophenols) were used as substrates
-
-
-
additional information
?
-
-
PPO shows activity with biphenols, triphenol but not with monophenols
-
-
-
additional information
?
-
-
L-tyrosine and hydroquinone are ineffective as substrates
-
-
-
additional information
?
-
-
protocatechuic acid (3,4-dihydroxybenzoic acid) shows little or no activity as a sole substrate
-
-
-
additional information
?
-
-
the enzyme fails to oxidize hydroquinone, phenol, or tyrosine
-
-
-
additional information
?
-
-
the enzyme shows no activity towards caffeic acid, DL-Dopa, ferulic acid and phenol
-
-
-
additional information
?
-
-
this enzyme is an o-diphenol oxidase, and no cresolase activity has been found
-
-
-
additional information
?
-
P93622
tyrosine is not a substrate
-
-
-
additional information
?
-
I7HUF2
the enzyme catalyzes the oxidation of ortho-diphenols to the corresponding quinones
-
-
-
additional information
?
-
-
polyphenol oxidase shows no activity with L-tyrosine, digallol, gallic acid, and methyl gallate
-
-
-
additional information
?
-
-
the enzyme shows minimal activity toward monophenol compounds such as tyramine, tyrosine and tyrosine methyl ester
-
-
-
NATURAL SUBSTRATES
NATURAL PRODUCTS
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
LITERATURE
(Substrate)
COMMENTARY
(Product)
LITERATURE
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
(+)-catechin + O2
?
show the reaction diagram
Ferula sp.
-
-
-
-
?
(-)-epicatechin + O2
?
show the reaction diagram
Ferula sp.
-
-
-
-
?
2 4-methylcatechol + O2
2 4-methyl-1,2-benzoquinone + 2 H2O
show the reaction diagram
-
-
-
-
?
2 catechol + O2
2 1,2-benzoquinone + 2 H2O
show the reaction diagram
-
-
-
-
?
2 o-diphenol + O2
2 o-quinone + 2 H2O
show the reaction diagram
I7HUF2
-
-
-
?
3,4,5-trihydroxy-L-phenylalanine + O2
?
show the reaction diagram
-
cytotoxicity of TOPA
-
-
?
4-methylcatechol + O2
4-methyl-1,2-benzoquinone + H2O
show the reaction diagram
Ferula sp.
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
Ferula sp.
-
-
-
-
?
catechol + 1/2 O2
1,2-benzoquinone + H2O
show the reaction diagram
-
-
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
Ferula sp.
-
-
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
probably the major substrate in vivo
-
-
?
chlorogenic acid + O2
?
show the reaction diagram
-
formation of a highly reactive o-quinone intermediate which then could interact with NH2 groups of lysine, SCH3 groups of methionines and indole rings of tryptophan in nucleophilic addition and in polymerization reactions, the so-called browning and greening reactions
-
-
?
D-catechin + O2
?
show the reaction diagram
-
-
-
-
?
dihydroxyphenylalanine + O2
dihydroxyphenylalanine quinone + H2O
show the reaction diagram
-
-
-
-
?
dopamine + O2
?
show the reaction diagram
-
-
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-dopa + 1/2 O2
L-dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-tyrosine + L-dopa + O2
L-dopa + dopaquinone + H2O
show the reaction diagram
-
-
-
-
?
L-tyrosine + L-dopa + O2
L-dopa + dopaquinone + H2O
show the reaction diagram
-
pathway of melanin biosynthesis, detailed overview
cytotoxicity of L-DOPA
-
?
L-tyrosine + O2
dihydroxyphenylalanine + H2O
show the reaction diagram
-
-
-
-
?
additional information
?
-
-
extremely low levels of activity suggest that this protein likely plays no direct metabolic role in the biodegradation of catecholamines
-
-
-
additional information
?
-
-
PPO II inhibits cultures of Escherichia coli and it accumulates on the wounded sites of tobacco leaves indicating that it may act as a defense role in plat defense system
-
-
-
additional information
?
-
-
the enzyme catalyzes the oxidation of o-phenolic substrates to o-quinones, which are subsequently polymerized to dark-coloured pigments. Polyphenoloxidase is considered to be the main contributor to browning discolouration and darkening in fruits and vegetables
-
-
-
additional information
?
-
-
expressionlevels of polyphenol oxidase activity exhibiting enzymes in the organism, overview
-
-
-
additional information
?
-
-
mechanical damage by Hemileia vastatrix fungus, the causal agent of the leaf orange rust disease, inoculation and Leucoptera coffeella, the coffee leaf miner, infestation caused different responses in PPO activity in different Coffea species, level of damage or resistance, overview
-
-
-
additional information
?
-
Ferula sp.
-
polyphenol oxidase is a major enzyme responsible for the browning reaction in damaged plant tissues and fruits
-
-
-
additional information
?
-
-
PPO activity increases in the transition from the vegetative stage to the generative stage
-
-
-
additional information
?
-
-
PPO activity is associated with color changes associated with browning and lycopene degradation, the commercial variety Naomi is more susceptible to enzymatic browning than the local varieties Pizzutello, Rosa Maletto and PO228, due to higher PPO activity levels, lycopene is an antioxidant agent that reconstitutes the polyphenols oxidized by the action of PPO
-
-
-
additional information
?
-
-
PPO oxidizes o-diphenolic compounds to the corresponding o-quinones in the presence of oxygen, subsequently the o-quinones polymerize with other o-quinones, proteins, amino acids etc., resulting in the formation of brown complexes, the enzyme is one of the main enzymes responsible for quality loss in strawberry taste due to phenolic degradation
-
-
-
additional information
?
-
-
role of the enzyme in the biosynthetic scheme of betalains, overview
-
-
-
additional information
?
-
-
the enzyme is considered as defence oxidative enzyme, is vital the physiological defence strategy adapted by plants to insect herbivory and pathogen attack
-
-
-
additional information
?
-
-
the enzyme plays a role in enzymatic browning, rapid discolouration of leaf, stem and root tissue after injury and strong pigmentation of tissue extracts, PPO and phenolic compounds could be an important part of the plants defence system against pests and diseases, including root parasitic nematodes, e.g. Radopholus similis
-
-
-
additional information
?
-
-
tyrosinase is known to be a key enzyme in melanin biosynthesis, involved in determining the color of mammalian skin and hair, various dermatological disorders, such as melasma, age spots and sites of actinic damage, arise from the accumulation of an excessive level of epidermal pigmentation
-
-
-
additional information
?
-
I7HUF2
the enzyme catalyzes the oxidation of ortho-diphenols to the corresponding quinones
-
-
-
COFACTOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
heme
-
the enzyme contains heme
additional information
-
if L-DOPA is an active cofactor, its formation as an intermediate during o-dopaquinone production is controversial
-
METALS and IONS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
Ca2+
-
highly activates PPO
Ca2+
-
124% activity at 10 mM
Co2+
-
1 mM, slight stimulation
copper
-
the copper centers in the protein are directly involved in the catechol oxidation
copper
-
a copper-containing enzyme with a dinuclear copper centre
copper
-
contains copper
Cu+
-
1 mM, 234% activity
Cu2+
-
1 mM, 241% activity, enzyme contains 0.24% copper
Cu2+
-
type 3 copper enzyme, coordination number of 4 for each copper atom, CuII-CuII distance of 2.9 A
Cu2+
-
binuclear copper center each coordinated by three histidine nitrogen atoms, in the oxidized enzyme structure the 2 copper II centers contain a hydroxide bridging group completing the four-coordinated trigonal pyramidal coordination sphere, in the reduced form the CuI-CuI separation increases to 4.4 A and a water molecule coordinates to one copper
Cu2+
-
active site binding
Cu2+
-
bound to the enzyme, the central domain contains two copper binding sites, mettyrosinase, the resting form of tyrosinase, contains two tetragonal Cu(II) ions antiferromagnetically coupled through an endogenous bridge, although hydroxide exogenous ligands other than peroxide are bound to the copper site, the exogenous oxygen molecule is bound as peroxide and bridges the two copper centers
Cu2+
-
bound to the enzyme, presently available for any tyrosinases, the central domain contains two copper binding sites, mettyrosinase, the resting form of tyrosinase, contains two tetragonal Cu(II) ions antiferromagnetically coupled through an endogenous bridge, although hydroxide exogenous ligands other than peroxide are bound to the copper site, the exogenous oxygen molecule is bound as peroxide and bridges the two copper centers
Cu2+
-
copper-containing metalloprotein
Cu2+
-
copper-containing enzyme
Cu2+
-
copper-containing enzyme
Cu2+
-
two Cu2+ ions per catalytic center
Cu2+
-
a copper enzyme
Cu2+
-
copper enzyme
Cu2+
-
copper-containing enzyme
Cu2+
-
when the concentration of PPO is about 66 mg/l, it shows its highest catalytic efficiency in the presence of 0.0001 mM Cu2+
Cu2+
-
activates
Cu2+
Q2UNF9
the enzyme contains two copper ions (CuA and CuB) within the so-called coupled type 3 copper site, in the catalytic binuclear centre. The two copper ions in the catalytic centre of AoCO4 are each coordinated by the three histidine residues: His102 (a3), His110 (loop before a4) and His119 (a4) for CuA, and His284 (a8), His288 (a8) and His312 (a9) for CuB
Cu2+
I7HUF2
a type 3 copper protein
Fe2+
-
activates
Fe2+
-
activates
H2O2
-
the exogenous oxygen molecule is bound as peroxide and bridges the two copper centers, conferring a distinct O2-Cu(II) charge transfer
Hg2+
-
activates
Mg2+
-
highly activates PPO
Mg2+
-
stimulates activity to 112% at 10 mM
Mn2+
-
highly activates PPO
Mn2+
-
activates
Ni2+
-
activates
Pb2+
-
1 mM, slight stimulation
Zn2+
-
1 mM, slight stimulation
Zn2+
-
activates
Zn2+
-
122% activity at 0.1 mM
Mn2+
-
stimulates activity to 120% at 10 mM
additional information
-
artificial dinuclear copper complexes as functional models for catechol oxidase
additional information
-
Na+, K+, Cl- and SO42- have no effect on enzyme activity
INHIBITORS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
1-ethyl-3-(3-dimethylaminopropyl) carbodiimide
-
irreversible inactivation, second-order rate constants
1-Phenyl-2-thiourea
-
-
1-Phenyl-2-thiourea
-
complete inhibition at 5 mM
1-Phenyl-2-thiourea
-
94.4% inhibition at 0.0293 mM
2,3-Dihydroxybenzoic acid
Q9ZP19
-
2,3-Dihydroxybenzoic acid
-
-
2,4-dihydroxy-N-(3,4,5-trihydroxybenzyl)benzamide
-
IC50: 0.550 mM
2,4-dihydroxy-N-(4-hydroxybenzyl)benzamide
-
IC50: 1.820 mM
2-hydroxy-2,4,6-cycloheptatrien-1-one
-
trivial name tropolone
2-hydroxy-2,4,6-cycloheptatrien-1-one
-
1 mM, complete inhibition of isoenzymes Ia, Ib and II
2-mercaptobenzothiazole
-
1 mM, 94% inhibition
2-mercaptoethanol
-
1 mM, 97% inhibition
2-mercaptoethanol
-
-
2-mercaptoethanol
Ferula sp.
-
competitive
2-mercaptoethanol
-
competitive
2-mercaptoethanol
-
-
2-methyl-4-[(E)-(4-nitrophenyl)methylidene]-1,3-oxazol-5(4H)-one
-
IC50: 0.00351 mM
2-methyl-4-[(E)-2-thienylmethylidene]-1,3-oxazol-5-one
-
IC50: 0.00311 mM
2-methyl-4-[(E,2Z)-3-phenyl-2-propenyliden]-1,3-oxazol-5(4H)-one
-
IC50: 0.00123 mM
3,4,5-trihydroxy-N-(3,4,5-trihydroxybenzyl)benzamide
-
IC50: 0.555 mM
3,4,5-trihydroxy-N-(4-hydroxybenzyl)benzamide
-
IC50: 1.180 mM
3,4,5-Trihydroxybenzoic acid
Q9ZP19
-
3,4,5-Trihydroxybenzoic acid
-
-
3,4-dihydroxy-N-(3,4,5-trihydroxybenzyl)benzamide
-
IC50: 0.280 mM
3,4-dihydroxy-N-(4-hydroxybenzyl)benzamide
-
IC50: 2.0 mM
3,4-dihydroxybenzoic acid
Q9ZP19
-
3,4-dihydroxybenzoic acid
-
-
3,5-dihydroxy-N-(3,4,5-trihydroxybenzyl)benzamide
-
IC50: 0.705 mM
3,5-dihydroxy-N-(4-hydroxybenzyl)benzamide
-
IC50: 0.710 mM
3-(acetoyloxy)-2-hydroxy-4-[[5-oxo-2-phenyl-1,3-oxazol-4(5H)-ylidene]methyl]phenylacetate
-
IC50: 0.00215 mM
3-aminophenyl-2,2'-methylenebis-(5,5-dimethylcyclohexane-1,3-dione)
-
IC50: 0.0021 mM
3-aminophenyl-2,2'-methylenebis-(cyclohexane-1,3-dione)
-
IC50: 0.00219 mM
3-chlorophenyl-2,2'-methylenebis-(5,5-dimethylcyclohexane-1,3-dione)
-
IC50: 0.0032 mM
4-chloromercuribenzoate
-
1 mM, 96, 94 and 95% inhibition of isoenzymes Ia, Ib and II respectively
4-hydroxybenzoic acid
-
-
4-Methylcatechol
-
field bean PPO obeys Michaelis-Menten kinetics and exhibits the phenomenon of inhibition by excess substrate for catechol, 4-methylcatechol and 4-tert-butylcatechol
4-tert-butylcatechol
-
field bean PPO obeys Michaelis-Menten kinetics and exhibits the phenomenon of inhibition by excess substrate for catechol, 4-methylcatechol and 4-tert-butylcatechol
4-[(E)-(4-nitrophenyl)methylidene]-2-phenyl-1,3-oxazol-5(4H)-one
-
IC50: 0.00323 mM
5,5'-dithiobis(2-nitrobenzoic acid)
-
-
8-hydroxyquinoline
-
-
Ag+
-
1 mM, 60% inhibition
Al3+
-
1 mM, 89% inhibition
ascorbate
-
-
ascorbic acid
-
0.066 mM, 26%, 59% and 96% inhibition of isoenzymes B, C, and D, respectively
ascorbic acid
-
-
ascorbic acid
-
pulp enzyme, 1 mM, complete inhibition
ascorbic acid
-
-
ascorbic acid
-
peel enzyme, 1 mM, complete inhibition
ascorbic acid
-
-
ascorbic acid
-
competitive with pyrolallol or catechol, noncompetitive with 4-methylcatechol as substrate. IC50: 0.357 mM in reaction with 4-methylcatechol, IC50: 0.818 mM in reaction with pyrogallol, IC50: 0.33 mM in reaction with catechol
ascorbic acid
-
inhibition of tyrosinase-catalyzed enzymatic browning by trapping the dopaquinone intermediate with cysteine or ascorbic acid, overview
ascorbic acid
-
-
ascorbic acid
-
endogenous ascorbic acid prevents betanidin oxidation, the effect of ascorbic acid on the tyrosinase-mediated catalysis is the reduction of the o-quinone product of the enzymatic reaction back to the corresponding o-diphenol with the concomitant oxidation of ascorbic acid to dehydroascorbic acid
ascorbic acid
-
markedly inhibits PPO
ascorbic acid
-
70.95% inhibition at 20 mM
ascorbic acid
-
11% residual activity at 400 mM in cultivar Violetto di Sicilia, 29% residual activity at 200 mM in cultivar Violetto di Provenza, 8% residual activity at 400 mM in cultivar Tema 2000
ascorbic acid
-
one of the most effective inhibitors of isozyme PPO 1, complete inhibition at 0.1 mM
ascorbic acid
-
-
ascorbic acid
-
nearly complete inhibition at 10 mM
askendoside B
-
; IC50 : 0.014 mM
askendoside D
-
-
azide
-
typical inhibitors of catecholoxidase, also inhibit the phenoloxidase activity of activated hemocyanin
Ba2+
-
moderately inhibits PPO
benzaldehyde
-
-
Benzoic acid
-
noncompetitive
Benzoic acid
Q9ZP19
-
Benzoic acid
-
-
Benzoic acid
-
64.86% inhibition at 10 mM
beta-mercaptoethanol
-
-
Boric acid
-
-
bryoamaride
-
-
catechol
-
field bean PPO obeys Michaelis-Menten kinetics and exhibits the phenomenon of inhibition by excess substrate for catechol, 4-methylcatechol and 4-tert-butylcatechol
catechol
-
catechol produces substrate inhibition above 16 mM
Cinnamic acid
-
-
citral
-
noncompetitive inhibitor
Citric acid
-
-
Citric acid
-
slight inhibition
Citric acid
-
68.92% inhibition at 20 mM
Citric acid
-
37% residual activity at 400 mM in cultivar Violetto di Sicilia, 59% residual activity at 200 mM in cultivar Violetto di Provenza, 18% residual activity at 400 mM in cultivar Tema 2000
Citric acid
-
32% residual activity at 10 mM
CN-
-
0.165 mM, 84%, 70%, 100% and 40% inhibition of isoenzymes A, B, C and D, respectively
CN-
-
1 mM, 82% inhibition
CN-
-
pulp enzyme, 1 mM, 80% inhibition
CN-
-
peel enzyme, 1 mM, 89% inhibition
Co2+
-
35% residual activity at 10 mM
Cu2+
-
moderately inhibits PPO
Cu2+
-
91.45% inhibition at 20 mM
Cu2+
-
33% residual activity at 10 mM
cucurbitane glycosides
-
isolated from Bryonia, structureactivity relationships, overview
-
Cuprizone
-
-
cycloartane glycosides
-
isolated from Astragalus sp., structureactivity relationships, overview
-
cyclocarposide
-
-
cycloorbicoside G
-
-
cyclosieversioside F
-
-
cysteine
-
1 mM, 92% inhibition
cysteine
-
pulp enzyme, 1 mM, complete inhibition
cysteine
-
-
cysteine
-
peel enzyme, 1 mM, complete inhibition
cysteine
-
inhibition of tyrosinase-catalyzed enzymatic browning by trapping the dopaquinone intermediate with cysteine or ascorbic acid, overview
D-fructose
-
D-fructose at different concentrations, PPO activities are measured at 25C and pH 7.0 to determine inhibitor effects of sugars on enzymatic activities. PPO activities from both cultivars show a decreasing pattern as sugar concentration in the assay medium increases
D-glucose
-
D-glucose at different concentrations, PPO activities are measured at 25C and pH 7.0 to determine inhibitor effects of sugars on enzymatic activities. PPO activities from both cultivars show a decreasing pattern as sugar concentration in the assay medium increases
diethyldithiocarbamate
-
0.066 mM, 31%, 40%, 36% and 84% inhibition of isoenzymes A, B, C, and D, respectively
diethyldithiocarbamate
-
-
diethyldithiocarbamate
-
pulp enzyme, 1 mM, complete inhibition
diethyldithiocarbamate
-
peel enzyme, 1 mM, complete inhibition
diethyldithiocarbamate
-
72.37% inhibition at 20 mM, the diethyldithiocarbamate-inhibited phenoloxidase-like activity can be perfectly restored by 10 mM Cu2+ while Zn2+ has no recovery effect
diethyldithiocarbamic acid
-
-
dithiothreitol
-
complete inhibition at 0.150 mM of the root enzyme
dithiothreitol
-
markedly inhibits PPO
DL-dithiothreitol
-
competitive with 4-methylcatechol, catechol or pyrogallol. IC50: 0.147 mM in reaction with 4-methylcatechol, IC50: 0.0329 mM in reaction with pyrogallol, IC50: 0.135 mM in reaction with catechol
dopamine
-
at high dopamine concentration, a decrease in activity is observed, indicating substrate inhibition
dopamine
-
dopamine produces substrate inhibition above 2 mM
EDTA
-
100 mM, 33%, 60%, 81% and 35% inhibition of isoenzymes A, B, C and D, respectively
EDTA
-
inhibits the root enzyme, while the pulp enzyme is only poorly inhiibited
EDTA
-
10 mM, 15% inhibition
EDTA
-
75% inhibition at 10 mM
EDTA
-
88.8% inhibition at 3.75 mM
EDTA
-
5% residual activity at 0.1 mM
epigallocatechin-3-O-gallate
-
-
Fe2+
-
88%, 68% and 80% inhibition of isoenzymes Ia, Ib, and II, respectively
FeCl3
-
markedly inhibits PPO
gallocatechin gallate
-
-
geranyl acetate
-
slight inhibition
glutathione
-
0.066 mM, 2%, 22% and 84% inhibition of isoenzymes B, C, and D, respectively
glutathione
-
1 mM, 98%, 95% and 96% inhibition of isoenzymes Ia, Ib, and II, respectively
glutathione
-
mixed type inhibition with 4-methylcatechol as substrate, noncompetitive with pyrogallol or catechol as substrates. IC50: 0.174 mM in reaction with 4-methylcatechol, IC50: 0.335 mM in reaction with pyrogallol, IC50: 0.323 mM in reaction with catechol
glutathione
-
-
glutathione
-
competitive
glutathione
-
-
glycine methyl ester hydrochloride
-
irreversible inactivation, second-order rate constants
GSH
-
increasing the concentration from 0 to 300 mM results in a high inhibitory effect on enzyme activity, mostly due to a drop of pH of the reaction solution to acidic values. Upon heating GSH at 90C, thermal degradation product formation is responsible for a partial inhibition. GSH-derived Maillard reaction products highly inhibit enzyme activity, inhibition efficiency increasing with heating time, 2-39 h and temperature, 80-100 C
hexadecyltrimethyl-ammonium bromide
-
-
Hg2+
-
1 mM, 84% inhibition
iodoacetate
-
1 mM; 1 mM: 46%, 39% and 31% inhibition of isoenzymes Ia, Ib, and II, respectively
isoascorbic acid
-
1 mM, 99% inhibition
isoascorbic acid
-
1 mM, complete inhibition of isoenzymes Ia, Ib and II
kojic acid
-
1 mM complete inhibition of isoenzymes Ia, Ib and II
kojic acid
-
IC50: 0.016.67 mM
kojic acid
-
-
kojic acid
-
IC50: 0.0163 mM
kojic acid
-
mixed inhibition
kojic acid
-
99% inhibition of diphenolase activity at 1 mM
kojic acid
-
typical inhibitors of catecholoxidase, also inhibit the phenoloxidase activity of activated hemocyanin
kojic acid
-
43% residual activity at 1 mM
kojic acid
-
-
kojic acid
-
11% residual activity at 10 mM
L-ascorbic acid
Ferula sp.
-
noncompetitive
L-ascorbic acid
-
competitive
L-ascorbic acid
-
complete inhibition at 0.90 mM of the root enzyme, and at 1 mM of the pulp enzyme
L-Cys
-
competitive with 4-methylcatechol, catechol or pyrogallol. IC50: 0.125 mM in reaction with 4-methylcatechol, IC50: 0.637 mM in reaction with pyrogallol, IC50: 0.15 mM in reaction with catechol
L-cysteine
-
-
L-cysteine
-
-
L-cysteine
-
-
L-cysteine
-
complete inhibition at 0.973 mM of the root enzyme, and at 1 mM of the pulp enzyme
L-cysteine
-
43.24% inhibition at 20 mM
L-cysteine
-
-
L-cysteine chloride
Ferula sp.
-
competitive
L-cysteine chloride
-
competitive
L-mimosine
-
IC50: 0.00368 mM
L-mimosine
-
typical inhibitors of catecholoxidase, also inhibit the phenoloxidase activity of activated hemocyanin
Luteolin 7-O-glucoside
-
noncompetitive, IC50: 0.500 mM
m-hydroxybenzoic acid
Q9ZP19
-
m-hydroxybenzoic acid
-
-
Maillard reaction products
-
potential natural inhibitors for use with minimally processed fruits
-
Metabisulfite
-
1 mM, 95% inhibition
Metabisulfite
-
-
Mg2+
-
inhibits activity at 0.01 mM
mimosine
-
1 mM, 88%, 79% and 82% inhibition of isoenzymes Ia, Ib, and II, respectively
morin
-
competitive, IC50: 2.320 mM
myrcene
-
competitive inhibitor
N,N-diethyldithiocarbamate
-
94.4% inhibition at 0.0293 mM
N-(2,4-dihydroxybenzyl)-2,4-dihydroxybenzamide
-
IC50: 0.029 mM
N-(2,4-dihydroxybenzyl)-3,4,5-trihydroxybenzamide
-
IC50: 0.017 mM
N-(2,4-dihydroxybenzyl)-3,4-dihydroxybenzamide
-
IC50: 0.011 mM
N-(2,4-dihydroxybenzyl)-3,5-dihydroxybenzamide
-
IC50: 0.0022 mM
N-benzyl-2,4-dihydroxybenzamide
-
IC50: 1.660 mM
N-benzyl-3,4,5-trihydroxybenzamide
-
IC50: 0.780 mM
N-benzyl-3,4-dihydroxybenzamide
-
IC50: 2.0 mM
N-benzyl-3,5-dihydroxybenzamide
-
IC50: 0.700 mM
N-benzylamide
-
IC50: 1.990 mM
N-benzylbenzamide derivatives
-
inhibitory potency, structure-activity relationships, overview
-
N-bromosuccinimide
-
-
NaCl
-
800 mM, 48%, 47%, 55% and 93% inhibition of isoenzymes A, B, C, and D, respectively
NaCl
-
29% residual activity at 0.1 mM
NaHSO3
-
0.066 mM, 64%, 50% and 27% inhibition of isoenzymes B, C, and D, respectively
Naphthol
-
strong inhibition of the reaction with catechol
neryl acetate
-
slight inhibition
o-hydroxybenzoic acid
Q9ZP19
-
o-hydroxybenzoic acid
-
-
o-phenanthroline
-
-
Orcinol
-
strong inhibition of the reaction with catechol
oxalic acid
-
-
p-aminobenzenesulfonamide
-
-
p-hydroxybenzoic acid
Q9ZP19
-
p-hydroxybenzoic acid
-
-
p-nitrophenol
-
strong inhibition of the reaction with catechol
Papain
-
proteolytic inactivation
-
phenyl-2,2'-methylenebis-(5,5-dimethylcyclohexane-1,3-dione)
-
IC50: 0.0026 mM
Phenylthiourea
Q9ZP19
-
Phenylthiourea
-
-
Phenylthiourea
-
typical inhibitors of catecholoxidase, also inhibit the phenoloxidase activity of activated hemocyanin
polyvinylpyrrolidone 40
-
-
-
procyanidin
-
inhibition intensity increases with NAD+. The inhibitory effect of oxidized procyanidins is twice that of native procyanidins
quercetin
-
competitive, IC50: 0.2 mM
resorcinol
-
10 mM, 40% inhibition
Sabinene
-
slight inhibition
Salicylhydroxamic acid
-
-
salicylic acid
-
uncompetitive
Sn2+
-
1 mM, 99% inhibition
SnCl2
-
markedly inhibits PPO
Sodium azide
-
-
Sodium azide
-
competitive with 4-methylcatechol or pyrogallol, noncompetitive with catechol as substrate. IC50: 1.31 mM in reaction with 4-methylcatechol, IC50: 10.3 mM in reaction with pyrogallol, IC50: 4.32 mM in reaction with catechol
Sodium azide
-
-
Sodium azide
-
noncompetitive
Sodium azide
-
10 mM, 100% inhibition
Sodium azide
-
-
Sodium bisulfite
-
1 mM, 97% inhibition
Sodium cyanide
-
noncompetitive
Sodium diethyl dithiocarbamate
-
-
Sodium diethyl dithiocarbamate
Ferula sp.
-
competitive
Sodium diethyl dithiocarbamate
-
cstrong competitive inhibitor
sodium disulfite
-
-
Sodium metabisulfite
Ferula sp.
-
competitive
Sodium metabisulfite
-
competitive
Sodium metabisulfite
-
complete inhibition at 0.109 mM of the root enzyme, and at 1 mM of the pulp enzyme
Sodium metabisulfite
-
markedly inhibits PPO
Sodium metabisulfite
-
one of the most effective inhibitors of isozyme PPO 1, complete inhibition at 0.1 mM
Sodium metabisulfite
-
27% residual activity at 10 mM
sodium sulfite
-
complete inhibition at 10 mM
succinic acid
-
complete inhibition at 1 mM
sulfonamide compounds
-
-
-
syringic acid
-
-
tartaric acid
-
2% residual activity at 400 mM in cultivar Violetto di Sicilia, 18% residual activity at 400 mM in cultivar Violetto di Provenza, 29% residual activity at 400 mM in cultivar Tema 2000
Thiourea
-
1 mM, 59% inhibition
Thiourea
-
strong inhibition of the reaction with catechol
Thiourea
-
competitive
Thiourea
-
84.46% inhibition at 10 mM
tropolone
-
competitive with pyrolallol or catechol, noncompetitive with 4-methylcatechol. IC50: 0.0109 mM in reaction with 4-methylcatechol, IC50: 0.0539 mM in reaction with pyrogallol, IC50: 0.0297 mM in reaction with catechol
tropolone
-
-
tropolone
-
pseudo first-order rate constants for inactivation
tropolone
-
97% inhibition of diphenolase activity at 1 mM
tropolone
-
most powerful specific PPO inhibitor. It reduces the PPO activity by 50%, when used at a low 0.01 mM concentration
tropolone
-
68% residual activity at 0.1 mM
tropolone
-
34% residual activity at 10 mM
tyramine
-
typical inhibitors of catecholoxidase, also inhibit the phenoloxidase activity of activated hemocyanin
Xanthogenate
-
1 mM, 94% inhibition
Zn2+
-
moderately inhibits PPO
Zn2+
-
45.39% inhibition at 20 mM
ZnSO4
-
-
Mn2+
-
inhibits activity at 0.01 mM
additional information
-
inhibition by high concentrations of the substrates caffeic acid, dihydrocaffeic acid, chlorogenic acid and rosmarinic acid
-
additional information
-
not inhibited by 10 mM EDTA, Cu2+, Mn2+, Zn2+, and Ba2+
-
additional information
-
not inhibited by 2,2'-dipyridyl, 1,10-phenanthroline and EDTA
-
additional information
-
inhibition by oxidation product from coffeoylquinic acid, oxidation product from (-)-epicatechin, oxidation product from (-)-epicatechin and caffeoylquinic acid, procyanidins from Avrolles cultivar, procyanidines from Kermerrien cultivar, procyanidins from Jeanne renard cultivar and oxidized procyanidins from Jeanne renard cultivar
-
additional information
-
no inhibition by EDTA, 4-aminobenzoate, salicylic acid, gallic acid and benzoic acid
-
additional information
-
sensitivity to inhibitors of the soluble and particulate enzyme forms, overview
-
additional information
-
synthesis and evaluation of several tetraketones with variable substituents at C-7, IC50 values, overview
-
additional information
-
synthesis and inhibitory potential of seventeen synthesized oxazolone derivatives, structure-activity relationships, overview
-
additional information
-
no inhibition by cycloalpioside D, cycloorbicoside A, askendoside G, and cucurbitacin L
-
additional information
-
structure, application and importance of inhibitors, overview
-
additional information
-
melanin plays a crucial protective role against skin photocarcinogenesis, however, the production of abnormal melanin pigmentation is a serious esthetic problem in humans, melanin biosynthesis can be inhibited by avoiding UV exposure, the inhibition of tyrosinase, the inhibition of melanocyte metabolism and proliferation, or the removal of melanin with corneal ablation, overview, structure, application and importance of inhibitors, overview
-
additional information
-
structure, application and importance of inhibitors, overview
-
additional information
-
no inhibition by kojic acid and 2-mercaptoethanol
-
additional information
-
inactivation of the enzyme in freshly prepared grape must under high hydrostatic pressure of 100-800 MPa, combined with moderate temperature (20-70C), or atmospheric pressure conditions in a temperature range of 55-70C, pressure and temperature act synergistically, except in the hightemperature-low-pressure region where an antagonistic effect is found, kinetics of thermal inactivation, overview
-
additional information
-
volatile flavor constituents of Yuzu, Mochiyuzu, Kabosu, Daidai, Naoshichi, Kiyookadaidai, Lisbon lemon, and Eureka lemon essential oils act as inhibitors of diphenolase activity
-
additional information
-
kinetics of enzyme inactivation by temperature and pressure
-
additional information
-
no inhibition by Ca2+ and Mg2+
-
additional information
-
not inhibited by SDS
-
ACTIVATING COMPOUND
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
2-oxo-butanoic acid
-
2.2 mM, catecholase activity: 140%
2-oxo-octanoic acid
-
3.2 mM, catecholase activity: 163%
Acrylic acid
-
1.25 mM, catecholase activity: 342%
Benzoic acid
-
134% relative activity at 10 mM
catechol
-
5 mM catechol results in a 5-8fold acceleration of the rate of oxidation of 2.5 mM L-Dopa
Chymotrypsin
-
proteolytic 2.5fold activation
-
Citric acid
-
148% relative activity at 10 mM
Cu2+
-
phenoloxdiase is a copper-containing metalloenzyme
ferulic acid
-
activates
hydrogen peroxide
-
activating at higher concentrations, however, the concentration of dihydrogen peroxide, formed during the reaction, does not reach this level
lipopolysaccharide
-
phenoloxidase activity is highest at 0.2 mg/ml
potassium sorbate
-
158% relative activity at 10 mM
-
propanoic acid
-
2 mM, catecholase activity: 245%
protocatechuic acid
-
activates
Pyruvic acid
-
1 mM, catecholase activity: 215%
SDS
-
activates due to formation of a SDS-PPO II complex
SDS
-
activates
SDS
-
severalfold activation at concentration below the critical micellar concentration of the enzyme, 15-20% activation at concentration below 0.3 mM, maximal activation at 1.25 mM, the activation by SDS and acidic pH results in a localized conformational change that is anchored around the catalytic site of PPO that alters the microenvironment of an essential glutamic residue
SDS
-
PPO from membrane shows no diphenolase activity unless it is activated by trypsin or sodium dodecyl sulfate
SDS
-
after the addition of SDS, the catecholoxidase activity of Eurypelma hemocyanin develops gradually over a period of 5 min until a constant activity is reached
SDS
-
enzyme is optimally activated by 10 mM SDS
SDS
-
when 0.04 mM SDS is added, the phenoloxidase activity starts to increase and peaks at 5 mM SDS (125fold increase)
SDS
-
170% activity at 10 mM
Sodium dodecyl sulfate
-
differential activation of the latent enzyme
sulfosalicylic acid
-
-
-
Trypsin
-
PPO from membrane shows no diphenolase activity unless it is activated by trypsin or sodium dodecyl sulfate, kinetics of the activation process of latent PPO by trypsin
-
Trypsin
-
proteolytic 3.5fold activation
-
Trypsin
-
when 0.001 mM trypsin is added, the phenoloxidase activity starts to increase and peaks at 0.04 mM trypsin (40fold increase)
-
lipoteichoic acid
-
phenoloxidase activity is highest at 0.2 mg/ml
-
additional information
-
the enzyme is activated on exposure to acid-pH, activation at pH 2.5 and at pH 4.0, reversal of the activation is possible at pH 7.0, the activation by SDS and acidic pH results in a localized conformational change that is anchored around the catalytic site of PPO that alters the microenvironment of an essential glutamic residue, concentration or on exposure to acid-pH, the enzymes possesses a core carboxylate essential to activity, this enhanced catalytic efficiency of PPO, overview
-
additional information
-
highest activity is measured using the following buffer composition: sodium phosphate + Triton X-100 (1%) + PVP (0.5%) + EDTA (1.0 mM) + sodium thiosulfate (0.25%)
-
additional information
-
mushroom tyrosinase's catecholase activity is activated by some n-alkyl carboxylic acid derivates whereas mushroom tyrosinase's cresolase activity is inhibited by the same substances
-
additional information
-
the presence of 5 mM of the following monophenolics has no effect on the rate of oxidation of 2.5 mM L-Dopa: 2-hydroxybenzoic acid (salicylic acid), 3-hydroxybenzoic acid, 4-hydroxybenzoic acid, (2-, 3-, or 4-)coumaric acids (2-, 3-, or 4-hydroxycinnamic acid). Additionally, neither 5 mM vanillin (4-hydroxy-3-methoxybenzaldehyde) nor pyrogallol (1,2,3-trihydroxybenzene) has any effect of the oxidation of 2.5 mM L-DOPA
-
additional information
-
beta-1,3-glucan has almost no effect on the phenoloxidase activity
-
KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.31
(+)-catechin
Ferula sp.
-
pH 6.5, 30C, stem enzyme
0.554
(+)-catechin
Ferula sp.
-
pH 6.5, 30C, leaf enzyme
0.99
(+)-catechin
-
pH 4.0, 25C
0.798
(-)-epicatechin
Ferula sp.
-
pH 6.0, 15C, leaf enzyme
2.89
(-)-epicatechin
Ferula sp.
-
pH 6.0, 15C, stem enzyme
4
(-)-epigallocatechin
Mycelia sterilia
-
-
1.3
(-)-epigallocatechin gallate
Mycelia sterilia
-
-
1.41
1-tert-butyl-catechol
-
pH 7.0
4
2,3,4-trihydroxybenzoic acid
-
-
5.6
2,3,4-trihydroxybenzoic acid
Q9ZP19
-
1.16
3,4-Dihydroxyphenyl acetic acid
-
-
4.4
3,4-Dihydroxyphenyl acetic acid
-
-
5.1
3,4-Dihydroxyphenyl acetic acid
-
-
1.05
3,4-dihydroxyphenyl propionic acid
-
-
1.89
3,4-dihydroxyphenyl propionic acid
-
-
2.9
3,4-dihydroxyphenylacetic acid
-
-
6
3,4-dihydroxyphenylacetic acid
Q9ZP19
-
6.66
3,4-dihydroxyphenylacetic acid
-
for Cucumis melo L. inodorus cv. Amarillo
7.18
3,4-dihydroxyphenylacetic acid
-
for Cucumis melo L. cantalupensis cv. Charentais
0.12
4-Methylcatechol
-
pH 7.0
1.2
4-Methylcatechol
-
pH 7.0, 25C
1.25
4-Methylcatechol
-
pH 3.5, 25C
1.809
4-Methylcatechol
-
-
1.9
4-Methylcatechol
-
-
2.36
4-Methylcatechol
-
-
2.77
4-Methylcatechol
-
pH 6.0, 25C
3.44
4-Methylcatechol
-
-
4
4-Methylcatechol
-
-
4.5
4-Methylcatechol
-
-
5.2
4-Methylcatechol
Q9ZP19
-
6.58
4-Methylcatechol
Ferula sp.
-
pH 6.0, 25C, leaf enzyme
6.78
4-Methylcatechol
Ferula sp.
-
pH 6.0, 25C, stem enzyme
8.3
4-Methylcatechol
-
pH 6.5, 25C
9.86
4-Methylcatechol
-
-
10
4-Methylcatechol
-
pH 7.0, 50C
11.6
4-Methylcatechol
-
-
4.1
4-tert-butylcatechol
-
-
3.9
4-tertiary butylcatechol
Q9ZP19
-
0.66
betanidin
-
pH 6.0
5
caffeic acid
-
-
9.5
caffeic acid
-
pH 6.5, 25C
28.6
catechin
Mycelia sterilia
-
-
0.1
catechol
-
pH 7.0
0.213
catechol
-
at pH 7.5 and 25C
0.3
catechol
-
-
0.414
catechol
-
pH 4.5, 25C
1.15
catechol
-
at 22C, pH not specified in the publication
1.2
catechol
-
; pH 6.5
1.62
catechol
-
pH 8.0, 25C
2.34
catechol
Ferula sp.
-
pH 7.0, 12C, leaf enzyme
2.64
catechol
Ferula sp.
-
pH 7.0, 12C, stem enzyme
4.2
catechol
-
isoenzyme B
4.2
catechol
Mycelia sterilia
-
-
4.5
catechol
-
-
5
catechol
-
-
5.95
catechol
-
pH 5.0, 25C
6.3
catechol
-
in 20 mM Tris-HCl buffer at pH 7.1 and 28C
6.6
catechol
-
isoenzyme A
7
catechol
-
isoenzyme C
7.174
catechol
-
SDS-activated hemocyanin
8
catechol
-
pH 7.0, 50C
9
catechol
Q9ZP19
-
10.5
catechol
-
-
12
catechol
-
-
21.1
catechol
-
pH 6.5, 25C
23.52
catechol
-
at pH 7.0 and 37C
25
catechol
-
-
36
catechol
-
isoenzyme D
44
catechol
-
isozyme PPO 1, in 0.2 M sodium phosphate buffer pH 7.0, 25C
69
catechol
-
pH 6.5, 25C
326.6
catechol
-
Km of pawpaw fruit PPO is comparable with the Km of PPO from other fruits
0.74
chlorogenic acid
-
-
0.764
chlorogenic acid
Ferula sp.
-
pH 6.0, 20C, leaf enzyme
0.87
chlorogenic acid
-
pH 7.0
0.88
chlorogenic acid
-
leaf enzyme
1
chlorogenic acid
-
pH 4.5, 25C, soluble, active enzyme form
1
chlorogenic acid
-
at pH 7.5 and 25C
1.07
chlorogenic acid
Ferula sp.
-
pH 6.0, 20C, stem enzyme
1.3 - 1.38
chlorogenic acid
-
pH 4.5, dependent on the assay method
2.27
chlorogenic acid
-
endosperm enzyme
3.5
chlorogenic acid
-
-
5.7
chlorogenic acid
-
pH 4.5, 25C, particulate, latent enzyme form
6.2
chlorogenic acid
-
pH 6.5, 25C
8
D-2-methyl-3,4-dihydroxyphenylalanine
-
-
0.47
D-catechin
-
-
1.2
D-catechin
-
pH 6.5, 25C
0.000219
D-Dopa
-
pH 7.2, 20C
0.38
D-Dopa
-
-
4.5
D-Dopa
-
-
15.02
D-Dopa
-
-
18.1
D-isoproterenol
-
-
1
digallol
-
pH 3.5, 25C
-
2.16
digallol
-
-
-
4.3
dihydrocaffeic acid
-
-
0.181
dopamine
-
SDS-activated hemocyanin
0.28
dopamine
-
-
0.427
dopamine
-
pH 6.5, 25C
0.6
dopamine
-
pH 6.5, 25C
0.72
dopamine
-
pH 7.0
1.22
dopamine
-
at substrate concentrations above 4 mM, substrate inhibition is observed and the data are fitted to a simple model for substrate inhibition. KM, kcat and KI are obtained for the inhibitory binding site
1.45
dopamine
-
substrate range 0.3-4 mM
1.5
dopamine
-
-
2.2
dopamine
-
-
2.8
dopamine
-
-
11.9
dopamine
-
-
6.8
L-2-methyl-3,4-dihydroxyphenylalanine
-
-
0.57
L-3,4-dihydroxyphenylalanine methyl ester
-
-
0.0000239
L-adrenaline
-
pH 7.2, 20C
0.000223
L-Dopa
-
pH 7.2, 20C
0.8
L-Dopa
-
-
0.96
L-Dopa
-
at 22C, pH not specified in the publication
1.02
L-Dopa
-
pH 6.0, 25C, soluble enzyme in presence of SDS
1.04
L-Dopa
-
-
1.18
L-Dopa
-
-
1.5
L-Dopa
-
pH 6.8, 30C
1.6 - 2
L-Dopa
-
at pH 7.0 and 37C
1.96
L-Dopa
-
pH 6.0, 25C, membrane enzyme in presence of SDS
2
L-Dopa
-
isoenzyme Ia
2.2
L-Dopa
-
isoenzyme Ib
2.45
L-Dopa
-
pH 6.0, 25C, soluble enzyme
2.565
L-Dopa
-
SDS-activated hemocyanin
2.69
L-Dopa
-
at pH 7.5 and 25C
3.1
L-Dopa
-
in 20 mM Tris-HCl buffer at pH 7.1 and 28C
3.5
L-Dopa
-
isoenzyme II
6.18
L-Dopa
-
pH 6.0, 25C, membrane enzyme
21.4
L-Dopa
-
pH 3.5, 25C
56.3
L-Dopa
-
pH 6.5, 25C
7.1
L-isoproterenol
-
-
0.0000194
L-noradrenaline
-
pH 7.2, 20C
1
myricetin
-
-
1.3
pyrogallol
-
isozyme PPO 1, in 0.2 M sodium phosphate buffer pH 7.0, 25C
3.42
pyrogallol
-
pH 9.0, 25C
3.9
pyrogallol
Mycelia sterilia
-
-
9.465
pyrogallol
-
-
12.5
pyrogallol
-
-
0.8
quercetin
-
-
2
rosmarinic acid
-
-
1.2
tert-butyl-catechol
-
pH 4.5, 25C, soluble, active enzyme form
1.23
tert-butyl-catechol
-
pH 4.5, 25C, particulate, latent enzyme form
0.91
tert-butylcatechol
-
-
2.8
tert-butylcatechol
-
-
2
verbascosid
-
-
8
Luteolin-7-glycoside
-
-
additional information
additional information
-
temperature and pH dependencis of the two enzyme forms, in absence or presence of SDS
-
additional information
additional information
-
the enhancement of kcat upon activation is accompanied by a marked shift in the pH optimum for the oxidation of t-butyl catechol from 4.5 to 6.0, an increased sensitivity to tropolone, altered susceptibility to proteolytic degradation and decreased thermostability
-
additional information
additional information
-
kinetics, tetranuclear carbonato-bridged copper(II) cluster with the macrocyclic ligand, overview
-
additional information
additional information
-
kinetics and activation energy, dependent on the locality of origin, the growth phase, and the tissue, overview
-
additional information
additional information
-
kinetics
-
additional information
additional information
-
general kinetic mechanism, the diphenolase activity is characterized by a lag period, whose duration depends on the substrate concentration, the pH, and the presence of catalytic amounts of o-diphenol, overview
-
additional information
additional information
-
kinetic mechanism, general kinetic model
-
additional information
additional information
-
betanidin degradation steady-state kinetics
-
additional information
additional information
-
kinetics
-
additional information
additional information
-
kinetics of the activation process of latent PPO by trypsin, Michaelis-Menten mechanism with double intermediate
-
additional information
additional information
-
thermodynamics and Michaelis-Menten kinetics, modeling in connection with pressure inactivation kinetics, overview
-
additional information
additional information
-
detailed kinetics, overview
-
additional information
additional information
-
Michaelis-Menten kinetics
-
additional information
additional information
I7HUF2
wild-type isozyme PPO-6 displays a low degree in cooperativity in catalysis. Cooperativity of the C197S mutein is significantly decreased at pH 3.5, under SDS activation at pH 5.0 the degree of cooperativity of the C197S mutein is similar to that of the PPO-6 wild-type enzyme
-
TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
641
1-tert-butyl-catechol
-
pH 7.0
3.05
2,3,4-trihydroxybenzoic acid
-
-
142
3,4-Dihydroxyphenyl acetic acid
-
-
533
3,4-Dihydroxyphenyl acetic acid
-
-
631.6
3,4-Dihydroxyphenyl acetic acid
-
-
850
3,4-Dihydroxyphenyl acetic acid
-
-
553.5
3,4-dihydroxyphenyl propionic acid
-
-
1830
3,4-dihydroxyphenyl propionic acid
-
-
11.48
3,4-dihydroxyphenylacetic acid
-
-
1.7
4-hydroxyphenylpropionic acid
-
pH 6.8, 10C, in methanol-glycerol cryosolvent
43
4-hydroxyphenylpropionic acid
-
pH 6.8, 25C, in methanol-glycerol cryosolvent
66.7
4-hydroxyphenylpropionic acid
-
pH 6.8, 25C, in aqueous buffer
26.66
4-Methylcatechol
-
-
841.6
4-Methylcatechol
-
-
842
4-Methylcatechol
-
pH 7.0
2340
4-Methylcatechol
-
-
48.05
4-tert-butylcatechol
-
-
106
caffeic acid
-
-
7.48
catechol
-
-
160
catechol
-
-
395
catechol
-
-
877.6
catechol
-
-
878
catechol
-
pH 7.0
121 - 135
chlorogenic acid
-
pH 4.5, dependent on the assay method
156
chlorogenic acid
-
-
176
chlorogenic acid
-
pH 7.0
785
chlorogenic acid
-
-
44.3
D-2-methyl-3,4-dihydroxyphenylalanine
-
-
0.000338
D-Dopa
-
pH 7.2, 20C
107.4
D-Dopa
-
-
340
D-Dopa
-
-
29.8
D-isoproterenol
-
-
1263
digallol
-
-
-
113
dihydrocaffeic acid
-
-
4.9
dopamine
-
-
5.7
dopamine
-
at substrate concentrations above 4 mM, substrate inhibition is observed and the data are fitted to a simple model for substrate inhibition. KM, kcat and KI are obtained for the inhibitory binding site
6
dopamine
-
substrate range 0.3-4 mM
29.9
dopamine
-
pH 6.8, 10C, in methanol-glycerol cryosolvent
133.2
dopamine
-
pH 6.8, 25C, in methanol-glycerol cryosolvent
282
dopamine
-
pH 6.5, 25C
439
dopamine
-
pH 6.8, 25C, in aqueous buffer
439
dopamine
-
pH 7.0
439
dopamine
-
-
875
dopamine
-
-
1350
dopamine
-
-
44.3
L-2-methyl-3,4-dihydroxyphenylalanine
-
-
35.5
L-3,4-dihydroxyphenylalanine methyl ester
-
-
0.00000148
L-adrenaline
-
pH 7.2, 20C
0.000459
L-Dopa
-
pH 7.2, 20C
42
L-Dopa
-
pH 6.8, 10C, in methanol-glycerol cryosolvent
107.4
L-Dopa
-
pH 6.8, 25C, in aqueous buffer
107.4
L-Dopa
-
-
141.1
L-Dopa
-
pH 6.8, 25C, in methanol-glycerol cryosolvent
1070
L-Dopa
-
-
29.4
L-isoproterenol
-
-
0.0000000912
L-noradrenaline
-
pH 7.2, 20C
22.7
Luteolin-7-glycoside
-
-
2.24
methyl 3-hydroxy-L-tyrosinate
-
pH 6.8, 10C, in methanol-glycerol cryosolvent
3.4
methyl 3-hydroxy-L-tyrosinate
-
pH 6.8, 25C, in aqueous buffer
8.9
methyl 3-hydroxy-L-tyrosinate
-
pH 6.8, 25C, in methanol-glycerol cryosolvent
213
myricetin
-
-
193
quercetin
-
-
109
rosmarinic acid
-
-
641.8
tert-butylcatechol
-
-
3320
tert-butylcatechol
-
-
1.9
tyramine
-
pH 6.8, 10C, in methanol-glycerol cryosolvent
7.4
tyramine
-
pH 6.8, 25C, in methanol-glycerol cryosolvent
25.9
tyramine
-
pH 6.8, 25C, in aqueous buffer
150
verbascosid
-
-
Ki VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.0632
2-mercaptoethanol
Ferula sp.
-
pH 7.0, stem enzyme
0.138
2-mercaptoethanol
Ferula sp.
-
pH 7.0, leaf enzyme
2.3
3,4,5-Trihydroxybenzoic acid
Q9ZP19
-
2.3
3,4,5-Trihydroxybenzoic acid
-
-
0.0075
ascorbic acid
-
-
0.0031
beta-mercaptoethanol
-
-
0.32
citral
-
pH 6.8, 35C
19.5
cysteine
-
-
29.64
dopamine
-
at substrate concentrations above 4 mM, substrate inhibition is observed and the data are fitted to a simple model for substrate inhibition. KM, kcat and KI are obtained for the inhibitory binding site
0.00067
glutathione
-
-
0.0119
kojic acid
-
with dopamine as a substrate
7.75
kojic acid
-
pH 6.8, 35C
0.0718
L-ascorbic acid
Ferula sp.
-
pH 7.0, stem enzyme
0.0815
L-ascorbic acid
Ferula sp.
-
pH 7.0, leaf enzyme
0.0145
L-cysteine
-
-
0.116
L-cysteine chloride
Ferula sp.
-
pH 7.0, stem enzyme
0.126
L-cysteine chloride
Ferula sp.
-
pH 7.0, leaf enzyme
0.0477
L-mimosine
-
with dopamine as a substrate
1.75
L-tyrosine
-
-
2.78
myrcene
-
pH 6.8, 35C
0.0000743
oxalic acid
-
-
0.0267
p-aminobenzenesulfonamide
-
-
0.088
quercetin
-
pH 6.8, 30C
0.0454
Sodium diethyl dithiocarbamate
Ferula sp.
-
pH 7.0, stem enzyme
0.0645
Sodium diethyl dithiocarbamate
Ferula sp.
-
pH 7.0, leaf enzyme
0.0259
Sodium metabisulfite
Ferula sp.
-
pH 7.0, stem enzyme
0.119
Sodium metabisulfite
Ferula sp.
-
pH 7.0, leaf enzyme
0.0214
syringic acid
-
-
0.00058
tropolone
-
-
0.2782
tyramine
-
with dopamine as a substrate
0.0055
Metabisulfite
-
-
additional information
additional information
-
-
-
additional information
additional information
-
fitting attempts reveal that inhibition by phenylthiourea and azide is not in accordance with a competitive binding model, the binding affinity of the inhibitors can not be determined by fitting the data
-
IC50 VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
3.7
2,3-Dihydroxybenzoic acid
-
-
0.55
2,4-dihydroxy-N-(3,4,5-trihydroxybenzyl)benzamide
-
IC50: 0.550 mM
1.82
2,4-dihydroxy-N-(4-hydroxybenzyl)benzamide
-
IC50: 1.820 mM
0.00351
2-methyl-4-[(E)-(4-nitrophenyl)methylidene]-1,3-oxazol-5(4H)-one
-
IC50: 0.00351 mM
0.00311
2-methyl-4-[(E)-2-thienylmethylidene]-1,3-oxazol-5-one
-
IC50: 0.00311 mM
0.00123
2-methyl-4-[(E,2Z)-3-phenyl-2-propenyliden]-1,3-oxazol-5(4H)-one
-
IC50: 0.00123 mM
0.555
3,4,5-trihydroxy-N-(3,4,5-trihydroxybenzyl)benzamide
-
IC50: 0.555 mM
1.18
3,4,5-trihydroxy-N-(4-hydroxybenzyl)benzamide
-
IC50: 1.180 mM
3.8
3,4,5-Trihydroxybenzoic acid
-
-
0.28
3,4-dihydroxy-N-(3,4,5-trihydroxybenzyl)benzamide
-
IC50: 0.280 mM
2
3,4-dihydroxy-N-(4-hydroxybenzyl)benzamide
-
IC50: 2.0 mM
2.8
3,4-dihydroxybenzoic acid
-
-
0.705
3,5-dihydroxy-N-(3,4,5-trihydroxybenzyl)benzamide
-
IC50: 0.705 mM
0.71
3,5-dihydroxy-N-(4-hydroxybenzyl)benzamide
-
IC50: 0.710 mM
0.00215
3-(acetoyloxy)-2-hydroxy-4-[[5-oxo-2-phenyl-1,3-oxazol-4(5H)-ylidene]methyl]phenylacetate
-
IC50: 0.00215 mM
0.0021
3-aminophenyl-2,2'-methylenebis-(5,5-dimethylcyclohexane-1,3-dione)
-
IC50: 0.0021 mM
0.00219
3-aminophenyl-2,2'-methylenebis-(cyclohexane-1,3-dione)
-
IC50: 0.00219 mM
0.0032
3-chlorophenyl-2,2'-methylenebis-(5,5-dimethylcyclohexane-1,3-dione)
-
IC50: 0.0032 mM
0.00323
4-[(E)-(4-nitrophenyl)methylidene]-2-phenyl-1,3-oxazol-5(4H)-one
-
IC50: 0.00323 mM
0.32
Anisaldehyde
-
noncompetitive, IC50: 0.320 mM
0.33
ascorbic acid
-
competitive with pyrolallol or catechol, noncompetitive with 4-methylcatechol as substrate. IC50: 0.357 mM in reaction with 4-methylcatechol, IC50: 0.818 mM in reaction with pyrogallol, IC50: 0.33 mM in reaction with catechol
0.014
askendoside B
-
IC50 : 0.014 mM
1.2
Benzoic acid
-
-
0.49
beta-mercaptoethanol
-
-
0.05
cuminaldehyde
-
noncompetitive, IC50: 0.050 mM
0.135
DL-dithiothreitol
-
competitive with 4-methylcatechol, catechol or pyrogallol. IC50: 0.147 mM in reaction with 4-methylcatechol, IC50: 0.0329 mM in reaction with pyrogallol, IC50: 0.135 mM in reaction with catechol
0.323
glutathione
-
mixed type inhibition with 4-methylcatechol as substrate, noncompetitive with pyrogallol or catechol as substrates. IC50: 0.174 mM in reaction with 4-methylcatechol, IC50: 0.335 mM in reaction with pyrogallol, IC50: 0.323 mM in reaction with catechol
0.91
glutathione
-
-
0.047
isoliquiritigenin
-
mixed-type, IC50: 0.047 mM
0.016
kojic acid
-
IC50: 0.016.67 mM
0.0163
kojic acid
-
IC50: 0.0163 mM
0.15
L-Cys
-
competitive with 4-methylcatechol, catechol or pyrogallol. IC50: 0.125 mM in reaction with 4-methylcatechol, IC50: 0.637 mM in reaction with pyrogallol, IC50: 0.15 mM in reaction with catechol
0.15
L-cysteine
-
-
0.00368
L-mimosine
-
IC50: 0.00368 mM
0.00038
L-tyrosine
-
-
0.5
Luteolin 7-O-glucoside
-
noncompetitive, IC50: 0.500 mM
1.1
m-hydroxybenzoic acid
-
-
2.32
morin
-
competitive, IC50: 2.320 mM
0.029
N-(2,4-dihydroxybenzyl)-2,4-dihydroxybenzamide
-
IC50: 0.029 mM
0.017
N-(2,4-dihydroxybenzyl)-3,4,5-trihydroxybenzamide
-
IC50: 0.017 mM
0.011
N-(2,4-dihydroxybenzyl)-3,4-dihydroxybenzamide
-
IC50: 0.011 mM
0.0022
N-(2,4-dihydroxybenzyl)-3,5-dihydroxybenzamide
-
IC50: 0.0022 mM
1.66
N-benzyl-2,4-dihydroxybenzamide
-
IC50: 1.660 mM
0.78
N-benzyl-3,4,5-trihydroxybenzamide
-
IC50: 0.780 mM
2
N-benzyl-3,4-dihydroxybenzamide
-
IC50: 2.0 mM
0.7
N-benzyl-3,5-dihydroxybenzamide
-
IC50: 0.700 mM
1.99
N-benzylamide
-
IC50: 1.990 mM
3.6
o-hydroxybenzoic acid
-
-
0.12
oxalic acid
-
-
0.23
p-aminobenzenesulfonamide
-
-
1.3
p-hydroxybenzoic acid
-
-
0.0026
phenyl-2,2'-methylenebis-(5,5-dimethylcyclohexane-1,3-dione)
-
IC50: 0.0026 mM
0.043
Phenylthiourea
Q9ZP19
-
0.07
Phenylthiourea
-
-
0.2
quercetin
-
competitive, IC50: 0.2 mM
4.32
Sodium azide
-
competitive with 4-methylcatechol or pyrogallol, noncompetitive with catechol as substrate. IC50: 1.31 mM in reaction with 4-methylcatechol, IC50: 10.3 mM in reaction with pyrogallol, IC50: 4.32 mM in reaction with catechol
0.4
syringic acid
-
-
0.0297
tropolone
-
competitive with pyrolallol or catechol, noncompetitive with 4-methylcatechol. IC50: 0.0109 mM in reaction with 4-methylcatechol, IC50: 0.0539 mM in reaction with pyrogallol, IC50: 0.0297 mM in reaction with catechol
SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
0.00018
-
substrate caffeic acid or catechol, leaf enzyme extract
0.00042
-
substrate caffeic acid, leaf enzyme extract
0.00042
-
substrate coumaric acid, leaf enzyme extract
0.00054
-
substrate 3-hydroxytyrosine, leaf enzyme extract
0.0006
-
substrate 3-hydroxytyrosine, leaf enzyme extract
0.0006
Coffea guarini, Coffea stenophylla
-
substrate coumaric acid, leaf enzyme extract
0.00084
-
substrate 3-hydroxytyrosine, leaf enzyme extract
0.0009
-
substrate 3-hydroxytyrosine, leaf enzyme extract
0.0012
-
substrate catechol, leaf enzyme extract
0.0014
-
substrate caffeic acid, leaf enzyme extract
0.002
-
substrate caffeic acid, leaf enzyme extract
0.002
-
substrate 3-hydroxytyrosine, leaf enzyme extract
0.002
-
substrate 4-methylcatechol, leaf enzyme extract
0.002
-
substrate 3-hydroxytyrosine, leaf enzyme extract
0.0022
-
substrate catechol, leaf enzyme extract
0.003
-
substrate 4-methylcatechol, leaf enzyme extract
0.003
Coffea guarini
-
substrate 3-hydroxytyrosine, leaf enzyme extract
0.004
-
substrate caffeic acid, leaf enzyme extract
0.004
-
substrate 3-hydroxytyrosine, leaf enzyme extract
0.004
-
substrate 5-caffeoyl quinic acid, leaf enzyme extract
0.004
-
substrate caffeic acid, leaf enzyme extract
0.0045
-
substrate catechol, leaf enzyme extract
0.005
-
substrate caffeic acid, leaf enzyme extract
0.005
-
substrate 5-caffeoyl quinic acid, leaf enzyme extract
0.006
-
substrate catechol, leaf enzyme extract
0.006
-
substrate caffeic acid, leaf enzyme extract
0.0063
-
substrate catechol, leaf enzyme extract
0.0065
-
substrate catechol, leaf enzyme extract
0.007
-
substrate 5-caffeoyl quinic acid or 4-methylcatechol, leaf enzyme extract
0.008
-
substrate catechol, leaf enzyme extract
0.008
-
substrate 5-caffeoyl quinic acid, leaf enzyme extract
0.008
-
substrate caffeic acid, leaf enzyme extract
0.0083
-
substrate 4-methylcatechol, leaf enzyme extract
0.01
-
substrate catechol, leaf enzyme extract
0.011
-
substrate 5-caffeoyl quinic acid, leaf enzyme extract
0.0124
-
substrate 5-caffeoyl quinic acid, leaf enzyme extract
0.014
Coffea guarini
-
substrate caffeic acid, leaf enzyme extract
0.016
-
substrate 5-caffeoyl quinic acid, leaf enzyme extract
0.017
-
substrate 5-caffeoyl quinic acid, leaf enzyme extract
0.018
-
substrate 4-methylcatechol, leaf enzyme extract
0.019
-
substrate 4-methylcatechol, leaf enzyme extract
0.02
-
substrate 4-methylcatechol, leaf enzyme extract
0.023
-
substrate 4-methylcatechol, leaf enzyme extract
0.023
-
substrate catechol, leaf enzyme extract
0.026
-
substrate 5-caffeoyl quinic acid, leaf enzyme extract
0.03
-
substrate 4-methylcatechol, leaf enzyme extract
0.036
-
substrate catechol, leaf enzyme extract
0.04
-
substrate 4-methylcatechol, leaf enzyme extract
0.045
Coffea guarini
-
substrate catechol, leaf enzyme extract
0.051
-
substrate 5-caffeoyl quinic acid, leaf enzyme extract
0.073
Coffea guarini
-
substrate 4-methylcatechol, leaf enzyme extract
0.09
Coffea guarini
-
substrate 5-caffeoyl quinic acid, leaf enzyme extract
0.145
-
using L-DOPA as substrate, crude enzyme, at pH 7.5 and 25C
1
-
reaction with catechol
1.32
-
crude extract, at pH 7.0, 25C
2.2
Mycelia sterilia
-
reaction with catechol
4.458
-
using L-DOPA as substrate, after 30.76fold purification, at pH 7.5 and 25C
4.5
-
reaction with pyrogallol
5.5
-
reaction with (-)-epigallocatechin gallate
5.7
Mycelia sterilia
-
reaction with pyrogallol
7.3
-
reaction with (-)-epigallocatechin
8.7
Mycelia sterilia
-
reaction with (-)-epigallocatechin gallate
8.76
-
isozyme PPO 1 after 6.6fold purification, at pH 7.0, 25C
10
Mycelia sterilia
-
reaction with (-)-epigallocatechin
13.15
Ferula sp.
-
purified stem enzyme
18.18
-
purified recombinant enzyme
18.7
-
partially purified soluble, active enzyme form, substrate tert-butyl-catechol
24.1
-
solubilized, crude enzyme
41.6
Ferula sp.
-
purified leaf enzyme
42.57
-
purified enzyme
59.46
-
purified enzyme
66
P43311
-
91.5
-
purified particulate, latent enzyme form, substrate tert-butyl-catechol
241.5
-
isozyme PPO 2 after 183fold purification, at pH 7.0, 25C
788.3
-
partially purified enzyme
1574
Q9ZP19
-
227700
-
highly purified enzyme, substrate catechol
additional information
-
isoenzyme A, 0.0016 units, isoenzyme B, 0.011 units, isoenzyme C, 0.0013 units/mg, isoenzyme D, 0.0028 units, 1 unit is defined as absorbance change at 420 nm of 0.001 per min
additional information
-
46000 units/mg, 1 unit is defined as absorbance change at 420 nm of 0.001 per min
additional information
-
13160.0 units/mg, 1 unit is defined as absorbance change at 420 nm of 0.1 per min
additional information
-
68077.0 units/mg, 1 unit is defined as absorbance change of 0.001 per min at 25C
additional information
-
10512.0 units/mg, 1 unit is defined as absorbance change at 420 nm of 0.1 per min and per ml enzyme solution
additional information
-
; 4500 units/mg, 1 unit is defined as absorbance change at 420 nm of 0.01 per min
additional information
-
isoenzyme Ia, 123 units/mg, isoenzyme Ib, 113 units/mg, isoenzyme II, 242 units/mg, 1 unit is defined as absorbance change at 420 nm of 0.1 per min
additional information
-
-
additional information
-
-
additional information
-
-
additional information
Ferula sp.
-
substrate specificity, tissue specific activities, overview
additional information
-
assay optimization
additional information
-
analysis of browning parameters
additional information
-
-
additional information
-
-
additional information
-
compared to PPO from R405-2000, a nonembryogenic cultivar, PPO from coker 312 (embryogenic cultivar) shows a higher PPO activity increasing markedly form primary culture to third subculture
additional information
-
polyphenol oxidases are induced in cowpea plants by wounding. The highest activity levels are detected 48 h after this stimulus in both wounded and neighbor-to-wounded unifoliates of cowpea seedlings. The increase of activity is in the order of 13 to 15fold, respectively, in comparison to control unifoliates
additional information
-
the specific activity of the crude enzyme is 3.72 units/mg, the specific activity of the 28.24fold purified enzyme is 105 units/mg, one unit is defined as an increase in the rate of absorbance of 0.001 per min, using L-dopa as substrate, at pH 7.1 and 28C
pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
3.5 - 4.5
-
dependent on the substrate, overview
4 - 6
-
dependent on conditions, overview
4
-
catechol oxidation
4.5 - 5.8
Mycelia sterilia
-
-
4.5
-
native enzyme
4.5
-
assay at
4.5
-
latent, nonactivated membrane isozyme
5
-
isoenzymes Ia and Ib
5
-
reaction with 4-methylcatechol
5
-
recation with 4-methylcatechol
5
-
assay at
5
-
assay at
5.3 - 5.7
-
natural mixture of tea leaf catechins as substrate
5.5 - 7.5
-
soluble enzyme, in absence of SDS. Membrane PPO activity is almost negligible at these pH values
5.5
-
there are two peaks of optimal pH, at pH 5.5 and pH 7.0
6 - 7
-
leaf and endosperm enzyme
6 - 7
Ferula sp.
-
dependent on the substrate, overview
6
-
; rapid decrease in activity at higher and lower pH
6
-
isoenzyme II
6
-
activated enzyme
6
-
with substrate 4-methylcatechol
6
-
assay at
6
-
substrate: 4-methylcatechol, optimal pH is dependent of the substrate
6
-
optimal pH, highest activity is measured using the following buffer composition: sodium phosphate + Triton X-100 (1%) + PVP (0.5%) + EDTA (1.0 mM) + sodium thiosulfate (0.25%)
6
-
assay at; optimal pH using 4-methylcatechol as substrate
6.5 - 7
-
latent, nonactivated soluble isozyme
6.5 - 7
-
PPO activity varies with pH and is the greatest at pH 6.5-7.0
6.5
-
isoenzyme B
6.5
-
-
6.5
-
activated membrane isozyme
6.5
-
assay at
6.5
-
with substrate catechol
6.5
-
assay at
6.5
-
assay at
6.8
-
isoenzyme A
7
-
isoenzyme D
7
-
reaction with catechol
7
-
reaction with catechol
7
-
assay at
7
-
assay at
7
-
for Cucumis melo L. cantalupensis cv. Charentais
7
-
there are two peaks of optimal pH, at pH 5.5 and pH 7.0
7
-
substrate: catechol, optimal pH is dependent of the substrate
7
-
optimal pH, highest activity is measured using the following buffer composition: sodium phosphate + Triton X-100 (1%) + PVP (0.5%) + EDTA (1.0 mM) + sodium thiosulfate (0.25%)
7
-
assay at
7
-
optimum pH for isozyme PPO 1
7
Q2UNF9
assay at
7.2 - 8
-
dependent on the locality of origin, the growth phase, and the tissue, overview
7.2
-
isoenzyme C
7.5
-
reaction with pyrogallol
7.5
-
for Cucumis melo L. inodorus cv. Amarillo
7.5
-
substrate: pyrogallol 4-methylcatechol, optimal pH is dependent of the substrate
8
-
reaction with pyrogallol
8
-
with substrate catechol
9
-
recombinant enzyme
9
-
with substrate pyrogallol
additional information
-
the enhancement of kcat upon activation is accompanied by a marked shift in the pH optimum from pH 4.5 to pH 6.0 for the oxidation of t-butyl catechol from 4.5 to 6.0, an increased sensitivity to tropolone, altered susceptibility to proteolytic degradation and decreased thermostability, overview
pH RANGE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
2.5 - 9
-
-
3 - 5.5
-
50% activity at pH 3.5 and pH 5.5, 25% activity at pH 3.0
3 - 5.5
-
-
3.5 - 7
-
inactive at pH 3.0 and pH 7.5, half-maximal activity at pH 3.5 and pH 6.2
3.5 - 7.5
-
-
4 - 8.5
-
pH optimum is determined over a pH 4.0-8.5 range
4 - 9
-
pH-profile
4 - 9
-
PPO activities are determined in a pH range of 4.0-9.0
4 - 9
-
activity range
4.1 - 4.4
-
74% and 87% of maximal activity
5 - 7.5
Ferula sp.
-
-
6 - 7.5
-
at pH 6.0, isozyme PPO 1 activity increases drastically, reaching maximum activity at pH 7.0 and then again radically decreases at pH 7.5
6 - 9.5
-
highest activity and stability within a neutral and alkaline pH range
additional information
-
pH profile, overview
additional information
-
catecholase activity pH profile
additional information
-
pH profile for the trypsin-activated PPO, pH is a determining factor in the expression of enzyme activity, it alters the ionization state of amino acid side chains or of the substrate, overview
TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
5 - 20
-
enzyme exhibits the greatest activity in the temperature zone of 5-20C
5
-
incubation time: 5 min, optimal temperature depends on incubation time
12 - 30
Ferula sp.
-
dependent on the substrate, overview
20 - 40
-
dependent on the locality of origin, the growth phase, and the tissue, overview
20
-
reaction with 4-methylcatechol; reaction with pyrogallol
20
-
reaction with pyrogallol
20
-
with substrate 4-methylcatechol
20
-
assay at
25 - 30
-
leaf and endosperm enzyme
25
-
assay at
25
-
assay at
25
-
assay at
25
-
assay at
25
-
assay at
25
-
assay at
25
-
assay at
25
-
assay at
25
-
assay at
25
-
assay at
25
Q2UNF9
assay at
30 - 35
-
soluble, active enzyme form
30 - 65
-
dependent on the substrate, overview
30
-
recombinant enzyme
30
-
with substrate catechol
30
-
incubation time: 40 min, optimal temperature depends on incubation time
35 - 45
-
optimum temperature for isozyme PPO 1
35
-
-
40
-
reaction with catechol
40
-
with substrate catechol
45
-
reaction with catechol
50
-
SDS-PPO II complex
50
-
with substrate pyrogallol
60
-
melon PPO has maximum activity at 60C in both Charentais and Amarillo cultivars
70
-
particulate, latent enzyme form
additional information
-
temperature optimum for recation with 4-methylcatechol is below 10C
TEMPERATURE RANGE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
4 - 80
-
the phenoloxidase activity stays almost the same or decreases slightly up to 60C, and decreases rapidly at 80C. The average phenoloxidase activity increases at 4C, 25C, 40C, and 60C in a time-dependent manner, but no increase is observed at 80C
5 - 70
Ferula sp.
-
-
5 - 80
-
-
5 - 80
-
crude enzyme exhibits a maximum activity at 5-20C, but a brief exposure to 40-80C results in a rapid decline or complete loss of the enzyme activity
10 - 60
-
-
20 - 65
-
94% of maximal activity at 30C, 78% of maximal activity at 20C, rapid decline of activity above 65C; enzyme retains more than 50% of its activity from 20C to 65C
20 - 70
-
at 20C the residual activity (26%) is maintained, at higher temperatures the activity decreases (50-60C) and from 65 to 70C there is no activity
20 - 80
-
-
30 - 65
-
30C: about 45% of maximal activity, 65C: about 60% of maximal activity
30 - 70
-
70% of maximal activity within at 30-60C, particulate, latent enzyme form
30 - 90
-
activity range
additional information
-
PPO activities are assayed at various reaction temperatures as controlled by a circulation water bath. The temperature is varied over the range of 5-80C (+/-0.1C)
pI VALUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
5.2
-
isoelectric focusing, soluble enzyme and membrane enzyme
9.5
-
isoelectric focusing
SOURCE TISSUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
SOURCE
P43311
high expression levels in developing berries and leaves
Manually annotated by BRENDA team
-
coker 312 seeds are used. Cotton cell suspensions are obtained from calli derived from hypocotyl segments of plant. Coker 312 cell suspensions show the development of embryogenic structures, R405-2000 seeds are used. Cotton cell suspensions are obtained from calli derived from hypocotyl segments of plant. R405-2000 cell suspensions does not show the development of embryogenic structures
Manually annotated by BRENDA team
Alternaria tenuis A-2
-
-
-
Manually annotated by BRENDA team
-
intrauterine immature egg
Manually annotated by BRENDA team
-
pulp and peel
Manually annotated by BRENDA team
-
grape must
Manually annotated by BRENDA team
Ferula sp.
-
-
Manually annotated by BRENDA team
Ferula sp.
-
-
Manually annotated by BRENDA team
-
aerenchyma in the cortex
Manually annotated by BRENDA team
-
polyphenol oxidases are induced in cowpea plants by wounding
Manually annotated by BRENDA team
Ferula sp.
-
-
Manually annotated by BRENDA team
additional information
-
tissue distribution, overview
Manually annotated by BRENDA team
LOCALIZATION
ORGANISM
UNIPROT
COMMENTARY
GeneOntology No.
LITERATURE
SOURCE
-
80% of total activity
-
Manually annotated by BRENDA team
-
20% of total activity
-
Manually annotated by BRENDA team
-
solubel PPO isozyme
-
Manually annotated by BRENDA team
-
PPO from membrane shows no diphenolase activity unless it is activated by trypsin or sodium dodecyl sulfate
Manually annotated by BRENDA team
additional information
-
the localisation of PPO in the plant cell depends on the species, age, and, in fruits or vegetables, on maturity, PPO activity increases in the transition from the vegetative stage to the generative stage
-
Manually annotated by BRENDA team
MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
12000
-
gel filtration
671857
16100
-
gel filtration
713239
28200
-
PPO exists as two isoforms with molecular weights of 28.2 and 38.3 kDa, SDS-PAGE
688112
28300
-
PPO exists as two isoforms with molecular weights of 28.2 and 38.3 kDa, SDS-PAGE
688112
38000
Q9ZP19
SDS-PAGE
686666
39350
-
MALDI-TOF
701876
40000
P93622
SDS-PAGE
712216
40480
-
MALDI-TOF
701876
41000
-
pulp enzyme, gel filtration
440433
41000
-
peel enzyme, gel filtration
440437
53000
-
isoenzyme II, gel filtration
440441
53000
-
SDS-PAGE
701876
54000
-
gel filtration
658955
55000
-
SDS-PAGE
701760
56700
P93622
calculated from amino acid sequence
712216
58000
-
by partially denaturing SDS-PAGE multiple molecular forms of active PPO are detected
706120
61200
-
particulate, latent enzyme form, gel filtration
671593
65000
-
isoenzymes Ia and Ib, gel filtration
440441
65000
-
SDS-PAGE
699242
67000
-
enzymes A and B, gel filtration
440429
69000
-
gel filtration
659821
73000
-
by partially denaturing SDS-PAGE multiple molecular forms of active PPO are detected
706120
88000
-
gel filtration
440428
120000
-
gel filtration
440434
120000
I7HUF2
recombinant mutant C197S mutein-tagged isozyme PPO-6, native PAGE
726187
153800
-
gel filtration
710702
170000
-
incubation of native hemocyanin with trypsin, produces a band of 170000 Da with intense phenoloxidase activity
696393
190000
-
incubation of native hemocyanin with chymotrypsin, produces a band of 190000 Da with intense phenoloxidase activity
696393
220000
-
by partially denaturing SDS-PAGE multiple molecular forms of active PPO are detected
706120
240000
Mycelia sterilia
-
-
658789
250000
-
-
658789
250000
I7HUF2
recombinant Strep2-tagged isozyme PPO-6, native PAGE
726187
440000
-
gel filtration
675076
448000
-
gel filtration
711789
additional information
-
50000, 30000, and 20000 Da functional units of native enzyme, SDS-PAGE. 17675, 18162, and 29685 Da, mass spectrum shows the data processed by the maximum entropy deconvolution system (MaxEnt)
684704
SUBUNITS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
?
-
x * 100000, SDS-PAGE
?
-
x * 57000, SDS-PAGE
?
-
x * 65000, SDS-PAGE
?
-
x * 40000, SDS-PAGE
?
-
x * 40000, SDS-PAGE
?
-
? * 40000, SDS-PAGE
?
-
x * 37000, deduced from amino acid sequence
?
-
x * 36000, latent, nonactivated membrane isozyme, SDS-PAGE, x * 32000, trypsin-activated membrane isozyme, SDS-PAGE
?
-
x * 43200, recombinant enzyme, SDS-PAGE, x * 61151, unprocessed enzyme, sequence calculation, 43 124-43 204, recombinant enzyme, mass spectrometry
dimer
-
1 * 27000 + 1 * 25000, isoenzyme II, SDS-PAGE
dimer
I7HUF2
2 * 60000, recombinant mutant C197S mutein-tagged isozyme PPO-6, SDS-PAGE
dimer
Q2UNF9
the full-length form and the truncated form of AoCO4 are dimers in solution, the dimerisation does not have a clear functional role
heterodimer
-
1 * 75600 + 1 * 73000, proenzyme, estimated from SDS-PAGE
hexamer
-
6 * 78000, SDS-PAGE
homohexamer
-
6 * 75000, SDS-PAGE
monomer
-
1 * 60000, SDS-PAGE
monomer
Q9ZP19
SDS-PAGE
monomer
-
1 * 42000, SDS-PAGE
monomer
-
1 * 42000, SDS-PAGE
monomer
-
1 * 49000, SDS-PAGE
monomer
-
1 * 18000, SDS-PAGE
monomer
-
1 * 65000, isoenzyme Ib, SDS-PAGE
monomer
P43311
1 * 40000, mature enzyme, SDS-PAGE
monomer
-
1 * 66000, isoenzyme Ia, SDS-PAGE
monomer
P43311
1 * 56700, mature enzyme, enzyme is synthesized as a 67300 Da precursor protein, predicted from nucleotide sequence
monomer
-
1 * 36500, MALDI-TOF mass spectrometry
monomer
-
1 * 39000
monomer
-
1 * 40000
monomer
-
1 * 46000
monomer
-
1 * 30900
monomer
-
1 * 66700
monomer
-
1 x 59200, particulate, latent enzyme form, SDS-PAGE
multimer
-
by partially denaturing SDS-PAGE multiple molecular forms of active PPO are detected: 58 kDa, 73 kDa and 220 kDa
tetramer
-
-
tetramer
-
4 * 30000, SDS-PAGE
tetramer
-
2 * 134000 + 2 * 43000, alpha2beta2 subunit composition
tetramer
I7HUF2
4 * 60000, recombinant wild-type Strep2-tagged isozyme PPO-6, SDS-PAGE
trimer
-
3 * 34000, boiling for 20 min, SDS-PAGE
trimer
-
1 * 77000 + 1 * 80000 + 1 * 89000
monomer
-
1 * 49277, LC-ESI mass spectrometry
additional information
Q2UNF9
structure analysis
additional information
-
enzyme may be synthesized as a 67000 Da precursor that can be hydrolyzed to a 45000 Da form still retaining catalytic activity
additional information
-
N-terminal and C-terminal structural analyses by fragmentation, chromatography, MS and peptide sequencing of the purified recombinant enzyme, overview
additional information
-
the Stokes radius of the native enzyme is found to increase from 49.1 to 75.9 A upon activation of the enzyme, neither SDS nor acid-pH activation brought about any change in the quaternary structure
additional information
I7HUF2
isozyme PPO-6 is a tetramer, the surface-exposed Cys197 residue stabilizes the tetramer via a disulfide linkage
POSTTRANSLATIONAL MODIFICATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
glycoprotein
Q2UNF9
the full-length AoCO4 shows O-glycosylation at Thr14 (mannose residue) and N-glycosylation at Asn30 (N-acetylglucosamine residue), Asn104 (N-acetylglucosamineN-acetylglucosaminemannose), Asn222 (N-acetylglucosamine) and Asn348 (N-acetylglucosamine). The glycans in AoCO4 might be involved in stabilising the secreted protein
proteolytic modification
-
the N-terminal analysis of the protein reveals N-terminal processing taking place in the Kex2/furin-type protease cleavage site and removing the first 51 amino acids from the putative N-terminus
proteolytic modification
-
PPO from membrane shows no diphenolase activity unless it is roteolytically activated by trypsin, kinetics of the activation process of latent PPO by trypsin at pH 7.0 and 25C
glycoprotein
-
-
glycoprotein
-
13% carbohydrate
proteolytic modification
-
proteolytic activation by trypsin and chymotrypsin, proteolytic inactivation by papain
glycoprotein
-
-
ribonucleoprotein
-
-
glycoprotein
-
recombinant secreted enzyme, glycosylated at its only potential N-glycosylation site, with a glycan consisting of two N-acetylglucosamines and five mannoses, low amounts of shorter glycan forms can be detected at this site
proteolytic modification
-
the mature protein is processed from the C-terminus by a cleavage of a peptide fragment of about 20 kDa
Crystallization/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
AoCO4 is crystallised as the full-length form and truncated form from the mixture of three forms, X-ray diffraction structure determination and analysis at 2.5 A and 2.9 A resolution, respectively
Q2UNF9
crystal structure of the enzyme in resting dicupric CII-CuII state, in reduced dicuprous CuI-CuI form and in complex with the inhibitor phenylthiourea
-
hanging drop vapor diffusion method, using 30% (w/v) PEG-4000 in 100 mM buffer citrate pH 5.6 and 200 mM ammonium acetate, at 18C
P93622
pH STABILITY
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
2.5 - 3.5
-
purified enzyme, most unstable at, less than 10% activity remaining after 2 h
675167
3 - 10
-
the enzyme is stable within pH 8.0-10.0, retaining more than 80% of its activity. The enzyme is almost unstable and inactive when pH is below 3.0, only remaining less than 20% of its activity
727570
3 - 6
-
at pH 6.0, all cultivars are stable with an increase of activity from 6 to 8% around 30 min, but at 120 min the activity decreases by about 30%. At pH 3.0, PPO activity decreases quickly and strongly (about 60% after 120 min of treatment), whereas at pH 4.0 it is quite stable in each cultivar (about 20% after 120 min of treatment)
712219
4
-
1 h, purified recombinant enzyme, complete loss of activity
673560
4.5
-
purified enzyme, over 50% activity reamining after 24 h
675167
4.6 - 6.3
-
unstable below pH 3.0 and above pH 6.6, loss of 50% activity at both pH 2.4 and pH 7.0
440428
5 - 11
-
10% loss of activity after 48 h between pH 5.0 and 11.0
440433
5 - 11
-
peel enzyme
440437
5 - 6
-
enzyme retains 95% of its activity
701760
5 - 7.5
Ferula sp.
-
-
673779
5 - 7.5
-
purified enzyme, over 50% activity reamining after 48 h
675167
5
-
1 h, purified recombinant enzyme, loss of 50% activity
673560
5
-
cosiderable activity loss below pH 5.0
701876
5.6 - 6.5
-
purified enzyme, most stable at, over 50% remaining activity after 72 h
675167
6 - 7
-
enzyme retains 95% of its activity
701760
6
-
purified enzyme, most stable at, unstable at acidic pH
673785
7
-
stable at
673560
8 - 8.5
-
purified enzyme, over 50% activity reamining after 24 h
675167
9
-
purified enzyme, over 50% activity reamining after 4 h
675167
additional information
-
highest activity and stability within a neutral and alkaline pH range
673560
TEMPERATURE STABILITY
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
4 - 100
-
the enzyme is stable at 4C for 240 min, but is unstable at 75 and 100C. Heat treatment at 100C from 20 to 80 min decreases enzyme activity (62.5%)
712219
10 - 40
-
quite stable, purified enzyme
673783
20 - 30
-
72 h, purified enzyme, over 50% activity remaining
675167
20 - 30
-
60 min
701760
30
-
purified recombinant enzyme, half-life: 18 h
673560
30
Ferula sp.
-
60 min, purified enzyme, 40% reduced activity
673779
35
-
stable below 35C, 50% inactivation after 30 min at 44C, almost complete loss of activity at 60C
440428
35
-
60 min, about 5% loss of activity with pyrogallol. 60 min, about 10% loss of activity with 4-methylcatechol. 60 min, activity with catechol is stable
658960
35
-
PPO is maximum thermally stable up to 35C
713239
40 - 50
-
24 h, purified enzyme, over 50% activity remaining
675167
40
-
above, loss in activity
671857
40
-
purified recombinant enzyme, half-life: 3,75 h
673560
40
Ferula sp.
-
60 min, purified enzyme, 65% reduced activity
673779
40
-
the residual soluble enzyme activity decreases significantly when temperature reaches 40C
727570
45
-
30 min, purified enzyme, stable
673785
50
-
leaf enzyme, no loss of activity after 30 min, 50% loss of activity after 5 min at 80C, endosperm enzyme, 20% loss of activity after 30 min at 50C, 50% loss of activity after 2.5 min at 80C
440436
50
-
50 min, 50% inactivation
658788
50
-
purified recombinant enzyme, half-life: 15 min
673560
50
Ferula sp.
-
60 min, purified enzyme, complete inactivation
673779
50
-
30 min, purified enzyme, loss of 50% activity
673785
50
-
half-live 20 h at 50C
701876
55
-
half-lives of isoenzymes A, B and D: 5.4, 14,6 and 14.1 min respectively, isoenzyme C: stable for 50 min at 55C, half-life at 76C: 2.2 min
440426
55
-
60 min, about 30% loss of activity with pyrogallol and 4-methylcatechol. 60 min, activity with catechol is stable
658960
55
-
30 min, purified enzyme, loss of 50% activity
674089
55
-
10 min, partially purified enzyme, loss of 50% activity
675166
60 - 75
-
half-life values of the enzyme range from 17 to 77min
713387
60
-
peel enzyme, loss of 10% activity after 30 min
440437
60
-
50 min, 30% inactivation
658788
60
Ferula sp.
-
40 min, purified enzyme, irreversible denaturation
673779
60
-
1 h, purified enzyme, over 50% activity remaining
675167
60
-
enzyme shows thermostability up to 60C, half-live 2 h at 60C
701876
65
-
10 min, partially purified enzyme, almost complete inactivation
675166
70
-
pulp enzyme, loss of 20% activity after 10 min
440433
70
-
30 min, 92% loss of activity
659821
70
-
almost complete inactivation within 30 min, purified enzyme
673783
70
-
15 min, purified enzyme, over 50% activity remaining
675167
75
-
40 min, complete loss of activity with pyrogallol and 4-methylcatechol. 50 min, about 60% loss of activity with catechol, complete inactivation after 60 min
658960
75
-
30 min, purified enzyme, loss of 55%, 80%, and 70% activity with substrates 4-methylcatechol, catechol, and pyrogallol, respectively
674089
80
-
50 min, 20% inactivation
658788
80
-
purified enzyme, complete inactivation within 3 min
675101
80
-
15 min, purified enzyme, inactivation
675167
80
-
enzyme is highly stable even 5 min at 80C
706120
additional information
-
presence of a thermostable polyphenol oxidase forming and destabilizing mechanism in apricot. The loss of PPO thermostability by partial purification indicates the non-covalent nature of the stabilization
658950
additional information
-
the activated enzyme is less thermostable than the native enzyme, overview
671857
additional information
-
heat denaturation kinetics
674089
additional information
-
inactivation of the enzyme in freshly prepared grape must under high hydrostatic pressure of 100-800 MPa, combined with moderate temperature (20-70C), or atmospheric pressure conditions in a temperature range of 55-70C, pressure and temperature act synergistically, except in the hightemperature-low-pressure region where an antagonistic effect is found, overview, thermal inactivation of PPO in a biphasic model
674096
additional information
-
biphasic thermal inactivation kinetics
675166
GENERAL STABILITY
ORGANISM
UNIPROT
LITERATURE
The activated state of Eurypelma hemocyanin is stable for several hours.
-
inactivation kinetics under high pressure treatment at different temperatures, modeling in connection with thermal inactivation kinetics, the partially purified enzyme is stable up to a pressure of 400 mPA at 25C, 5% remaining activity at 800 MPa and 25C, inactive at 700-900 MPa and 40-50C, overview
-
STORAGE STABILITY
ORGANISM
UNIPROT
LITERATURE
isozyme PPO 2 is highly unstable such as after 24 h of storage PPO 2 activity is not detected
-
4C, 55% of the maximum activity at this cold-storage temperature
-
Purification/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
ammonium sulfate, DEAE-cellulose, DEAE-Sephadex, hydroxyapatite, electrofocusing
-
purified by gel filtration
-
AoCO4 is purified with a two-step purification procedure, consisting of cation and anion exchange chromatography
-
ammonium sulfate precipitation, column chromatography, gel filtration; ammonium sulfate precipitation, column chromatography, gel filtration; ammonium sulfate precipitation, column chromatography, gel filtration; ammonium sulfate precipitation, column chromatography, gel filtration; ammonium sulfate precipitation, column chromatography, gel filtration
A6N8J4, A6NAA0, A6YS04, A6YS05, C5MLZ1
nickel chelate column chromatography
-
Ni-NTA column chromatography
-
partially purified in a sequential two-phase system based on Triton X-114 and PEG-8000/phosphate, followed by ammonium sulfate fractionation
-
DEAE-Sepharose column chromatography and Sephadex G-75 gel filtration
-
native soluble, active enzyme form partially 3.3fold by ammonium sulfate fractionation, particulate, latent active enzyme form 40fold to homogeneity by phase partitioning in Triton X-114 followed by anion exchange and hydrophobic interaction chromatography, and gel filtration
-
native enzyme, 25.8fold from stem and 43.3 from leaves, by (NH4)2SO4 precipitation, dialysis, and gel filtration
Ferula sp.
-
native enzyme partially, solubilization by Triton X-100 in presence of polyvinyl polypyrrolidone, 32.fold by ammonium sulfate fractionation and dialysis
-
using a Sephadex G-200 column balanced with 0.1 M sodium phosphate buffer (pH 6.5)
-
99% purity
-
ammonium sulfate, DEAE-Sephacel, Phenyl-agarose, Sephadex G-100
-
native enzyme from seeds
-
using a Sepharose 4B-L-tyrosine-p-amino benzoic acid affinity column
-
ammonium sulfate precipitation and DEAE-cellulose column chromatography
-
native enzyme 75.5fold to homogeneity from apples purification in presence of AEBSF and aprotinin by ammonium sulfate fractionation, dialysis, gel filtration, and hydrophobic interaction chromatography, followed by anion exchange and hydroxyapatite chromatography
-
native enzyme by anion exchange chromatography, ammonium sulfate fractionation, hydrophobic interaction chromatography, and gel filtration
-
optimization of enzyme extraction from roots, best using 0.2 M phosphate buffer at pH 7.0 with 5% insoluble polyvinylpyrrolidone and 0.25% Triton X-100, overview
-
ammonium sulfate, DEAE-toyopearl, butyl-toyopearl, Super Q toyopearl, hydroxyapatite, toyopearl HW 55
-
native enzyme from leaves 2.54fold by ammonium sulfate fractionation and gel filtration
-
; ammonium sulfate, DEAE-Sephadex A-50, Sephadex G-75
-
native enzyme 11.5fold by (NH4)2SO4 precipitation, dialysis, and L-tyrosine-4-aminobenzoic acid affinity chromatography
-
ammonium sulfate precipitation, DEAE Sepharose column chromatography, and Sephacryl S-100 gel filtration
-
ion exchange chromatography
-
native enzyme, partially from stem, root, and leaves, by (NH4)2SO4 precipitation and dialysis
-
Sephacryl S-300 gel filtration
-
phenol oxidases A and B, DEAE-Sepharose, partially purified
-
isoenzymes Ia, Ib and II ammonium sulfate, DEAE-cellulose, Sephacryl S-200, hydroxyapatite, Mono Q
-
ammonium sulfate precipitation, and phenyl Sepharose column chromatography
-
isoenzymes A, B, C and D, acetone precipitate, DEAE-cellulose
-
native tyrosinase from hemolymph to homogeneity by anion exchange and hydrophobic interaction chromatography
-
native enzyme 78fold to homogeneity
-
DEAE-toyopearl, copper-affinity chromatography, Sephadex 200, PAGE
-
recombinant secreted enzyme 4.9fold from culture supernatant by cation exchange chromatography and gel filtration to homogeneity
-
native enzyme 17.8fold by (NH4)2SO4 precipitation, dialysis, and ion exchange chromatography
-
using (NH4)2SO4 precipitation and ion-exchange chromatography
-
ammonium sulfate precipitation, Superose-R 12 column chromatography, and Sephadex G-75 gel filtration
P93622
hexadecyltrimethylammonium bromide extraction, ammonium sulfate, Q-Sepharose, Phenyl-Sepharose, hydroxylapatite
P43311
Cloned/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
AoCO4 is expressed in Trichoderma reesei under the strong cbh1 promoter, resulting in high yields of extracellular enzyme, corresponding to 1.5 g/l production of the enzyme
-
exression in Trichoderma reesei
Q2UNF9
expressed in Escherichia coli BL21(DE3) cells using pET30c expression vector (high expression) and in Pichia pastoris GS115 using both the secretory and non-secretory vectors pPICZ-A and pPICZA (low expression); expressed in Escherichia coli BL21(DE3) cells using pET30c expression vector (high expression) and in Pichia pastoris GS115 using both the secretory and non-secretory vectors pPICZ-A and pPICZA (low expression); expressed in Escherichia coli BL21(DE3) cells using pET30c expression vector (high expression) and in Pichia pastoris GS115 using both the secretory and non-secretory vectors pPICZ-A and pPICZA (low expression); expressed in Escherichia coli BL21(DE3) cells using pET30c expression vector (high expression) and in Pichia pastoris GS115 using both the secretory and non-secretory vectors pPICZ-A and pPICZA (low expression); expressed in Escherichia coli BL21(DE3) cells using pET30c expression vector (high expression) and in Pichia pastoris GS115 using both the secretory and non-secretory vectors pPICZ-A and pPICZA (low expression)
A6N8J4, A6NAA0, A6YS04, A6YS05, C5MLZ1
expressed in Escherichia coli BL21(deltaDE3) cells
-
expressed in Escherichia coli BL21(DE3) cells
-
gene RSc0337, sequence comparison
-
cloning of cDNA
-
gene ppo-6, expression of N-terminally Strep2-tagged isozyme PPO-6 in Escherichia coli strain Rosetta2(DE3) pLysSRARE2
I7HUF2
gene tyr2, DNA and amino acid sequence determination and analysis, overexpression in the native host under the strong cbh1 promoter, secretion of the recombinant enzyme into the culture supernatant
-
cloning of cDNA
P43311
EXPRESSION
ORGANISM
UNIPROT
LITERATURE
a 3.1fold increase in PPO activity over non-recombinant controls is obtained by expressing the PPO fragment without signal sequences and the CuC domain in Escherichia coli BL21 (DE3) using the pET30c vector
-
a decrease in activity is noted in the spring harvest as compared to winter harvest
-
ENGINEERING
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
C197S
I7HUF2
site-directed mutagenesis of isozyme PPO-6, the C197S-mutein still forms a tetrameric structure but shows impaired enzymatic efficiency and cooperativity and a reduction in stability compared to the wild-type enzyme
Renatured/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
method one is to resuspend the proteins twice in 50 mM Tris-HCl buffer (pH 7.5) with 5 mM dithiothreitol, 2% (v/v) Triton X-100 and 5 mM NaCl, followed by centrifugation at 14000 x g for 5 min. Method two is to resuspend the proteins in one-tenth volume of its original culture of inclusion body isolation buffer containing 20 mM Tris-HCl and 1% (v/v) Triton X-100, pH 7.5, and then in 50 mM Tris-HCl, pH 8.0, each followed by centrifugation at 14000 x g for 5 min; method one is to resuspend the proteins twice in 50 mM Tris-HCl buffer (pH 7.5) with 5 mM dithiothreitol, 2% (v/v) Triton X-100 and 5 mM NaCl, followed by centrifugation at 14000 x g for 5 min. Method two is to resuspend the proteins in one-tenth volume of its original culture of inclusion body isolation buffer containing 20 mM Tris-HCl and 1% (v/v) Triton X-100, pH 7.5, and then in 50 mM Tris-HCl, pH 8.0, each followed by centrifugation at 14000 x g for 5 min; method one is to resuspend the proteins twice in 50 mM Tris-HCl buffer (pH 7.5) with 5 mM dithiothreitol, 2% (v/v) Triton X-100 and 5 mM NaCl, followed by centrifugation at 14000 x g for 5 min. Method two is to resuspend the proteins in one-tenth volume of its original culture of inclusion body isolation buffer containing 20 mM Tris-HCl and 1% (v/v) Triton X-100, pH 7.5, and then in 50 mM Tris-HCl, pH 8.0, each followed by centrifugation at 14000 x g for 5 min; method one is to resuspend the proteins twice in 50 mM Tris-HCl buffer (pH 7.5) with 5 mM dithiothreitol, 2% (v/v) Triton X-100 and 5 mM NaCl, followed by centrifugation at 14000 x g for 5 min. Method two is to resuspend the proteins in one-tenth volume of its original culture of inclusion body isolation buffer containing 20 mM Tris-HCl and 1% (v/v) Triton X-100, pH 7.5, and then in 50 mM Tris-HCl, pH 8.0, each followed by centrifugation at 14000 x g for 5 min; method one is to resuspend the proteins twice in 50 mM Tris-HCl buffer (pH 7.5) with 5 mM dithiothreitol, 2% (v/v) Triton X-100 and 5 mM NaCl, followed by centrifugation at 14000 x g for 5 min. Method two is to resuspend the proteins in one-tenth volume of its original culture of inclusion body isolation buffer containing 20 mM Tris-HCl and 1% (v/v) Triton X-100, pH 7.5, and then in 50 mM Tris-HCl, pH 8.0, each followed by centrifugation at 14000 x g for 5 min
A6N8J4, A6NAA0, A6YS04, A6YS05, C5MLZ1
APPLICATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
agriculture
-
could help pawpaw growers and food processors to develop proper storage and processing methods to avoid the undesirable color changes
drug development
-
the enzyme is a target for development of specific inhibitors to avoid unfavorable enzymatic browning of plant-derived foods by tyrosinase causing decrease in nutritional quality and economic loss of food products
nutrition
-
the enzyme is a target for development of specific inhibitors to avoid unfavorable enzymatic browning of plant-derived foods by tyrosinase causing decrease in nutritional quality and economic loss of food products
food industry
-
PPO functions as an essential factor in the quality development of semi-finished tea products, especially black tea and Oolong tea
additional information
-
tyrosinase is an important enzyme in the food industry because during the processing of fruits and vegetables any wounding may cause cell disruption and lead to quinone formation, the enzymatic browning implies a considerable economic loss in the commercial production of fruits and vegetables, the appearance of food and beverages may be affected, as may the taste and its nutritional value, often decreasing the quality of the final product
agriculture
-
quality loss of fruits, the major enzyme responsible for the browning reaction is polyphenol oxidase
additional information
-
the enzyme needs to be inactivated in wine production from grape must, since it causes undesirable color and turbidity modifications, which can change the stability and organoleptic characteristics of grape juice and musts, overview