Information on EC 4.2.3.114 - gamma-terpinene synthase

Please wait a moment until all data is loaded. This message will disappear when all data is loaded.
Specify your search results
Mark a special word or phrase in this record:
Select one or more organisms in this record:
Show additional data
Do not include text mining results
Include (text mining) results (more...)
Include results (AMENDA + additional results, but less precise; more...)


The expected taxonomic range for this enzyme is: Gunneridae

EC NUMBER
COMMENTARY
4.2.3.114
-
RECOMMENDED NAME
GeneOntology No.
gamma-terpinene synthase
-
REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
geranyl diphosphate = gamma-terpinene + diphosphate
show the reaction diagram
major products sabinene and gamma-terpinene are formed by a cyclization mechanism involving a 1,2-hydride shift in the alpha-terpinyl cation intermediate
geranyl diphosphate = gamma-terpinene + diphosphate
show the reaction diagram
-
-
-
-
geranyl diphosphate = gamma-terpinene + diphosphate
show the reaction diagram
ionization of geranyl diphosphate folded in left-handed helical form gives, by syn-isomerization, (3R)-linalyl diphosphate, which by rotation about C2-C3 provides the cisoid, anti-endo conformation. Ionization and cyclization of this bound intermediate yield the (4R)-alpha-terpinyl cation that, following the 1,2-hydride shift, affords the terpinen-4-yl cation. Loss of the (5S)-proton terminates the reaction to generate gamma-terpinene
-
geranyl diphosphate = gamma-terpinene + diphosphate
show the reaction diagram
mechanism involves the cyclizazion of the acyclic precursor, loss of a proton from C5 to form the delta4 double bond, and a 1,2-hydride shift fom C4 to C8 to give gamma-terpinene
-
SYSTEMATIC NAME
IUBMB Comments
geranyl-diphosphate diphosphate-lyase (cyclizing, gamma-terpinene-forming)
Isolated from Thymus vulgaris (thyme) [1,2], Citrus limon (lemon) [3], Citrus unshiu (satsuma) [4] and Origanum vulgare (oregano) [5]. Requires Mg2+. Mn2+ less effective. The reaction involves a 1,2-hydride shift. The 5-pro-S hydrogen of geranyl diphosphate is lost. Traces of several other monoterpenoids are formed in addition to gamma-terpinene.
SYNONYMS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
ClcTS
-
-
-
-
OvTPS2
-
-
-
-
CAS REGISTRY NUMBER
COMMENTARY
68943-55-5
-
ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
six different variants of the gene are distinguishable according to sequence characteristics in intron 3, after comprehensive analysis in Origanum dubium, Origanum majorana, Origanum onites, and Origanum syriacum. The formation of characteristic essential oil compounds is associated with the presence of variants 1 and/or 3 and/or 4 in the gene. In plants lacking these variants, the compounds are completely absent or present in trace amounts only
UniProt
Manually annotated by BRENDA team
carvacrol-rich plant, cloning from chemically distinct Thymus caespititius plants
UniProt
Manually annotated by BRENDA team
SUBSTRATE
PRODUCT                      
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
LITERATURE
(Substrate)
COMMENTARY
(Product)
LITERATURE
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
geranyl diphosphate
gamma-terpinene + diphosphate
show the reaction diagram
-
-
-
?
geranyl diphosphate
gamma-terpinene + diphosphate
show the reaction diagram
-
-
ionization of geranyl diphosphate folded in left-handed helical form gives, by syn-isomerization, (3R)-linalyl diphosphate, which by rotation about C2-C3 provides the cisoid, anti-endo conformation. Ionization and cyclization of this bound intermediate yield the (4R)-alpha-terpinyl cation that, following the 1,2-hydride shift, affords the terpinen-4-yl cation. Loss of the (5S)-proton terminates the reaction to generate gamma-terpinene
?
geranyl diphosphate
gamma-terpinene + diphosphate
show the reaction diagram
-
plus small amounts of alpha-pinene, limonene
?
geranyl diphosphate
gamma-terpinene + diphosphate
show the reaction diagram
-
products are 71.4% gamma-terpinene, with lower amounts of limonene (9.1%), alpha-pinene (5.6%), beta-pinene (4.7%), alpha-terpinolene (3.7%), alpha-thujene (2.5%), alpha-terpinene (1.7%), myrcene (0.9%), sabinene (0.4%) and a trace of p-cymene
?
geranyl diphosphate
gamma-terpinene + diphosphate
show the reaction diagram
-
products are 80% gamma-terpinene and the minor products, alpha-thujene (7.2%), alpha-terpinene (6%), myrcene (2.6%), sabinene (1.3%), (+)-R-limonene (1.2%), alpha-pinene (1%) and alpha-phellandrene (0.8%), as well as trace amounts of p-cymene and beta-pinene
?
geranyl diphosphate
gamma-terpinene + diphosphate
show the reaction diagram
-
-
products are about 64% gamma-terpinen, 10% alpha-thujene, 4% myrcene, 4% alpha-terpinene, 2% limonene, 3% linalool, 2% terpinen-4-ol, 3% alpha-terpineol
?
geranyl diphosphate
gamma-terpinene + diphosphate
show the reaction diagram
-
plus minor products alpha-thujene, alpha-pinene, sabinene, beta-myrcene, alpha-terpinene
?
geranyl diphosphate
gamma-terpinene + diphosphate
show the reaction diagram
-
plus minor products such as alpha-terpinene and alpha-thujene
?
neryl diphosphate
gamma-terpinene + diphosphate
show the reaction diagram
-
-
75% gamma-terpinene, 20% alpha-thujene, 5% alpha-terpineol, partially purified enzyme
?
geranyl diphosphate + H2O
gamma-terpinene + diphosphate
show the reaction diagram
-
63% sabinene, 21% gamma-terpinene, 7% terpinolene, 6.5% limonene, and 2.5% myrcene
?
additional information
?
-
no substrate farnesyl diphosphate
-
-
-
METALS and IONS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
Mg2+
or Mn2+, Mn2+ is preferred over Mg2+
Mg2+
-
or Mn2+, required, Mg2+ is preferred over Mn2+
Mg2+
-
or Mn2+, required. Optimum concentration 20 mM
Mg2+
or Mn2+, required. Optimum concentration of Mg2+ 0.025 mM, 44% of the activity wit Mn2+
Mn2+
or Mg2+, Mn2+ is preferred over Mg2+, optimum concentration 0.6 mM
Mn2+
-
or Mg2+, required, about 60% of the efficiency qith Mg2+
Mn2+
-
or Mg2+, required. 50% of the efficiency with Mg2+
Mn2+
or Mg2+, required. Mn2+ is preferred over Mg2+, optimum concentration 0.001 mM
INHIBITORS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
4-hydroxymercuribenzoate
-
-
benzyl bromide
-
-
diethyl dicarbonate
-
-
diphosphate
-
-
EDTA
-
1 mM, complete inactivation
additional information
-
not inhibitory: gamma-terpinene, p-cymene, thymol
-
KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.0026
geranyl diphosphate
-
pH 6.8, 30C
0.0027
geranyl diphosphate
pH 7.0, 30C
0.0074
geranyl diphosphate
pH 7.1, 31C
0.00871
geranyl diphosphate
pH 6.8, 30C
0.014
geranyl diphosphate
-
pH 6.6, 30C
0.009
neryl diphosphate
-
pH 6.6, 30C
IC50 VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.0035
4-hydroxymercuribenzoate
Thymus vulgaris
-
pH 6.8, 30C
2
benzyl bromide
Thymus vulgaris
-
pH 6.0, 30C
0.01
diethyl dicarbonate
Thymus vulgaris
-
pH 7.0, 30C
0.5
diphosphate
Thymus vulgaris
-
pH 6.8, 30C
SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
149
-
pH 6.8, 30C
pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
pH RANGE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
6 - 6.5
half maximal activity
7.2 - 7.5
half maximal activity
TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
pI VALUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
4.9
-
isoelectric focusing
5.2
calculated
SOURCE TISSUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
SOURCE
glants of fruit lavedo and fruit peel
Manually annotated by BRENDA team
high expression in shoot of in vitro plantlet
Manually annotated by BRENDA team
additional information
no expression in root
Manually annotated by BRENDA team
LOCALIZATION
ORGANISM
UNIPROT
COMMENTARY
GeneOntology No.
LITERATURE
SOURCE
MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
96000
-
gel filtraion
717142
96000
-
gel fitlration
717145
SUBUNITS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
?
x * 68490, calculated
?
x * 66268, calculated
dimer
-
2 * 55000, SDS-PAGE
Crystallization/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
homology modeling based on gamma-terpinene synthase from Origanum vulgare. Besides the aspartate-rich region DDxxD, the sites Asp452, Thr456 and Glu460 involved on stabilization of active site by Mg2+ cofactor are also conserved
GENERAL STABILITY
ORGANISM
UNIPROT
LITERATURE
addition of either 20% glycerol or 1 mM substrate does not significantly improve stability
-
STORAGE STABILITY
ORGANISM
UNIPROT
LITERATURE
0C, 40 mM sodium phosphate, 5 mM MgCl2, 0.5 mM dithioerythritol, loss of 60% of activity within 1 week
-
Purification/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
Cloned/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
expression in Escherichia coli
expression in Escherichia coli
expression in Escherichia coli
EXPRESSION
ORGANISM
UNIPROT
LITERATURE
terpene synthase expression levels directly control the composition of the essential oil