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Information on EC 3.1.2.B5 - 3,4-hydroxyphenylacetyl-CoA thioesterase
for references in articles please use BRENDA:EC3.1.2.B5
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Please check here for current data: EC unknown
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preliminary BRENDA-supplied EC number
EC Tree 3 Hydrolases
3.1 Acting on ester bonds
3.1.2 Thioester hydrolases
3.1.2.B5 3,4-hydroxyphenylacetyl-CoA thioesterase
The expected taxonomic range for this enzyme is: Bacteria, Eukaryota
showSynonyms
PaaI, more
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
PaaI
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
3,4-dihydroxyphenylacetyl-CoA + H2O = 3,4-dihydroxyphenylacetate + CoA
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SYSTEMATIC NAME
IUBMB Comments
3,4-dihydroxyphenylacetyl-CoA hydrolase
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SUBSTRATE
PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
LITERATURE
COMMENTARY
Reversibility
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
3,4-dihydroxyphenylacetyl-CoA + H2O
3,4-dihydroxyphenylacetate + CoA
Substrates: the enzyme can liberate CoA from phenylacetyl-CoA and from hydroxyphenylacetyl-CoA substrates that form from the phenylacetate pathway
Products: -
Products: -
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3,4-dihydroxyphenylacetyl-CoA + H2O
3,4-dihydroxyphenylacetate + CoA
Substrates: -
Products: -
Products: -
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3,4-dihydroxyphenylacetyl-CoA + H2O
3,4-dihydroxyphenylacetate + CoA
Substrates: the enzyme can liberate CoA from phenylacetyl-CoA and from hydroxyphenylacetyl-CoA substrates that form from the phenylacetate pathway
Products: -
Products: -
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3,4-dihydroxyphenylacetyl-CoA + H2O
3,4-dihydroxyphenylacetate + CoA
Substrates: -
Products: -
Products: -
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3,4-dihydroxyphenylacetyl-CoA + H2O
3,4-dihydroxyphenylacetate + CoA
Substrates: the enzyme can liberate CoA from phenylacetyl-CoA and from hydroxyphenylacetyl-CoA substrates that are formed in the phenylacetate pathway
Products: -
Products: -
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3,4-dihydroxyphenylacetyl-CoA + H2O
3,4-dihydroxyphenylacetate + CoA
Substrates: -
Products: -
Products: -
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3,5-dihydroxyphenylacetyl-CoA + H2O
3,5-dihydroxyphenylacetate + CoA
Substrates: -
Products: -
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3,5-dihydroxyphenylacetyl-CoA + H2O
3,5-dihydroxyphenylacetate + CoA
Substrates: -
Products: -
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3,5-dihydroxyphenylacetyl-CoA + H2O
3,5-dihydroxyphenylacetate + CoA
Substrates: -
Products: -
Products: -
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3-hydroxyphenylacetyl-CoA + H2O
3-hydroxyphenylacetate + CoA
Substrates: -
Products: -
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3-hydroxyphenylacetyl-CoA + H2O
3-hydroxyphenylacetate + CoA
Substrates: -
Products: -
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3-hydroxyphenylacetyl-CoA + H2O
3-hydroxyphenylacetate + CoA
Substrates: -
Products: -
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4-hydroxyphenylacetyl-CoA + H2O
4-hydroxyphenylacetate + CoA
Substrates: -
Products: -
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4-hydroxyphenylacetyl-CoA + H2O
4-hydroxyphenylacetate + CoA
Substrates: -
Products: -
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4-hydroxyphenylacetyl-CoA + H2O
4-hydroxyphenylacetate + CoA
Substrates: -
Products: -
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phenylacetyl-CoA + H2O
phenylacetate + CoA
Substrates: -
Products: -
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phenylacetyl-CoA + H2O
phenylacetate + CoA
Substrates: -
Products: -
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additional information
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Substrates: no activity with 4-hydroxybenzoyl-CoA, 3-hydroxybenzoyl-CoA, 4-hydroxybenzyl-CoA, 4-hydroxyphenacyl-CoA, 3-hydroxyphenacyl-CoA, 4-chlorobenzoyl-CoA, 4-methoxybenzoyl-CoA. Low activity with acetyl-CoA, n-hexanoyl-CoA, n-butyryl-CoA, isobutyryl-CoA, beta-hydroxybutyryl-CoA, methylmalonyl-CoA, crotonyl-CoA
Products: -
Products: -
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additional information
?
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Substrates: no activity with 4-hydroxybenzoyl-CoA, 4-hydroxybenzyl-CoA, 4-hydroxyphenacyl-CoA
Products: -
Products: -
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NATURAL SUBSTRATE
NATURAL PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
LITERATURE
COMMENTARY
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
3,4-dihydroxyphenylacetyl-CoA + H2O
3,4-dihydroxyphenylacetate + CoA
Substrates: the enzyme can liberate CoA from phenylacetyl-CoA and from hydroxyphenylacetyl-CoA substrates that form from the phenylacetate pathway
Products: -
Products: -
?
3,4-dihydroxyphenylacetyl-CoA + H2O
3,4-dihydroxyphenylacetate + CoA
Substrates: the enzyme can liberate CoA from phenylacetyl-CoA and from hydroxyphenylacetyl-CoA substrates that form from the phenylacetate pathway
Products: -
Products: -
?
3,4-dihydroxyphenylacetyl-CoA + H2O
3,4-dihydroxyphenylacetate + CoA
Substrates: the enzyme can liberate CoA from phenylacetyl-CoA and from hydroxyphenylacetyl-CoA substrates that are formed in the phenylacetate pathway
Products: -
Products: -
?
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INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.0086
3,4-dihydroxyphenylacetyl-CoA
pH 8.1, 25°C, mutant enzyme N60A
0.048
3,4-dihydroxyphenylacetyl-CoA
pH 8.1, 25°C, mutant enzyme D75A
0.051
3,4-dihydroxyphenylacetyl-CoA
pH 8.1, 25°C, wild-type enzyme
0.055
3,4-dihydroxyphenylacetyl-CoA
pH 8.1, 25°C, mutant enzyme N60D
0.028
3,5-dihydroxyphenylacetyl-CoA
pH 8.1, 25°C, wild-type enzyme
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TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.0065
3,4-dihydroxyphenylacetyl-CoA
pH 8.1, 25°C, mutant enzyme D75A
0.012
3,4-dihydroxyphenylacetyl-CoA
pH 8.1, 25°C, mutant enzyme N60A
0.18
3,4-dihydroxyphenylacetyl-CoA
pH 8.1, 25°C, mutant enzyme N60D
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kcat/KM VALUE [1/mMs-1]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.1
3,4-dihydroxyphenylacetyl-CoA
pH 8.1, 25°C, mutant enzyme D75A
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Ki VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
Highest Expressing Human Cell Lines
Cell Line LinksPlease wait a moment until the data is sorted. This message will disappear when the data is sorted.
UNIPROT
ENTRY NAME
ORGANISM
NO. OF AA
NO. OF TRANSM. HELICES
MOLECULAR WEIGHT[Da]
SOURCE
SEQUENCE
LOCALIZATION PREDICTION
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable).
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable). Q9F9V0_AROEV
154
0
16550
TrEMBL
other Location (Reliability: 1)
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MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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SUBUNIT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
homotetramer
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CRYSTALLIZATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
C-terminal His-tagged enzyme is prepared for crystallization. The N-terminal Met is replaced by Ser-Leu. Crystals of the selenomethionine enzyme are grown in 13% polyethylene glycol, 0.1 M [bis(2-hydroxyethyl)imino]-tris(hydroxymethyl)methane (pH 6.0) and 0.2 M lithium sulfate at 18°C using the hanging drop vapor diffusion method. They are incubated in the presence of 30% glycerol before being flash-frozen in liquid nitrogen. The crystals belong to trigonal space group P3(1)21 with a = b = 69.9 A and c = 117.2 A
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PROTEIN VARIANTS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
H52A
1000fold decrease in the kcat/Km is observed with the 4-hydroxyphenylacetyl-CoA, and a 100fold decrease in the kcat/Km value is observed with the 3-hydroxyphenylacetyl-CoA or 3,4-dihydroxyphenylacetyl-CoA
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STORAGE STABILITY
ORGANISM
UNIPROT
LITERATURE
-80°C, stable for storage in 10 mM K+/Hepes buffer (pH 7.5) or in 10 mM Tris buffer (pH 8.1) containing 10 mM KCl for several months
0°C, pH 8.1, stored in 10 mM Tris buffer for several weeks without significant loss of activity
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REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
Song, F.; Zhuang, Z.; Finci, L.; Dunaway-Mariano, D.; Kniewel, R.; Buglino, J.A.; Solorzano, V.; Wu, J.; Lima, C.D.
Structure, function, and mechanism of the phenylacetate pathway hot dog-fold thioesterase PaaI
J. Biol. Chem.
281
11028-11038
2006
Aromatoleum evansii (Q9F9V0), Aromatoleum evansii DSM 6898 (Q9F9V0), Escherichia coli (P76084)
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EXTERNAL LINKS (specific for EC-Number 3.1.2.B5)
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