Information on EC 4.2.1.34 - (S)-2-Methylmalate dehydratase

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: Bacteria

EC NUMBER
COMMENTARY
4.2.1.34
-
RECOMMENDED NAME
GeneOntology No.
(S)-2-Methylmalate dehydratase
REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
(S)-2-Methylmalate = 2-methylfumarate + H2O
show the reaction diagram
-
-
-
-
REACTION TYPE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
condensation
-
-
-
-
elimination
-
-
-
-
PATHWAY
KEGG Link
MetaCyc Link
C5-Branched dibasic acid metabolism
-
glutamate degradation VI (to pyruvate)
-
Metabolic pathways
-
SYSTEMATIC NAME
IUBMB Comments
(S)-2-methylmalate hydro-lyase (2-methylfumarate-forming)
Also hydrates fumarate to (S)-malate.
SYNONYMS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
(+)-Citramalic hydro-lyase
-
-
-
-
Dehydratase, citramalate
-
-
-
-
Hydratase, mesaconate
-
-
-
-
Mesaconase
-
-
-
-
Mesaconase
-
-
Mesaconase
Rhodospirillum rubrum 1R
-
-
-
Mesaconase, mesaconate
-
-
-
-
Mesaconate hydratase
-
-
-
-
CAS REGISTRY NUMBER
COMMENTARY
9027-94-5
-
ORGANISM
COMMENTARY
LITERATURE
SEQUENCE CODE
SEQUENCE DB
SOURCE
Aerobic bacterium
-
-
-
Manually annotated by BRENDA team
Citrobacter amalonaticus YG1002
YG1002
-
-
Manually annotated by BRENDA team
Citrobacter freundii YG-0504
YG-0504
-
-
Manually annotated by BRENDA team
Morganella morganii YG-0601
YG-0601
-
-
Manually annotated by BRENDA team
Raoultella planticola IAM 1133
IAM 1133
-
-
Manually annotated by BRENDA team
Rhodospirillum rubrum 1R
strain 1R
-
-
Manually annotated by BRENDA team
SUBSTRATE
PRODUCT                      
REACTION DIAGRAM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
(Substrate)
LITERATURE
(Substrate)
COMMENTARY
(Product)
LITERATURE
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
(L)-citramalate
mesaconate + H2O
show the reaction diagram
-
-
-
-
-
(L)-citramalate
mesaconate + H2O
show the reaction diagram
Aerobic bacterium
-
-
-
-
-
(L)-citramalate
mesaconate + H2O
show the reaction diagram
Rhodospirillum rubrum, Rhodospirillum rubrum 1R
-
enzyme is specific to (L)-citramalate, the rate of dehydration of (D)-citramalate is below 10% of that for the (L) isomer
-
-
r
(S)-malate
fumarate + H2O
show the reaction diagram
-
-
-
-
(S)-malate
fumarate + H2O
show the reaction diagram
-
-
-
-
(S)-malate
fumarate + H2O
show the reaction diagram
Aerobic bacterium
-
-
-
-
Citramalate + H2O
Mesaconate
show the reaction diagram
-
-
-
-
-
Citramalate + H2O
Mesaconate
show the reaction diagram
-
-
-
-
-
Citramalate + H2O
Mesaconate
show the reaction diagram
-
-
-
-
-
Citramalate + H2O
Mesaconate
show the reaction diagram
Aerobic bacterium
-
-
-
-
Citramalate + H2O
Mesaconate
show the reaction diagram
-
-
-
-
-
Citramalate + H2O
Mesaconate
show the reaction diagram
-
L-citramalate
-
-
Citramalate + H2O
Mesaconate
show the reaction diagram
-
(+)-citramalate
-
-
Citramalate + H2O
Mesaconate
show the reaction diagram
Citrobacter amalonaticus YG-1002, Citrobacter amalonaticus YG1002, Morganella morganii NCIMB 232, Raoultella planticola IAM 1133, Morganella morganii NCIMB 9525, Morganella morganii YG-0601, Morganella morganii NCIMB 10466
-
-
-
-
-
Fumarate + H2O
L-Malate
show the reaction diagram
-
-
-
-
Fumarate + H2O
L-Malate
show the reaction diagram
-
-
-
-
Fumarate + H2O
L-Malate
show the reaction diagram
Aerobic bacterium
-
-
-
-
mesaconate
citramalate + H2O
show the reaction diagram
-
-
-
-
mesaconate
citramalate + H2O
show the reaction diagram
-
-
-
-
mesaconate
citramalate + H2O
show the reaction diagram
Aerobic bacterium
-
-
-
-
mesaconate
citramalate + H2O
show the reaction diagram
-
-
(+)-citramalate
-
additional information
?
-
-
key enzyme of the mesaconate pathway of (S)-glutamate fermentation
-
-
-
additional information
?
-
Aerobic bacterium
-
constitutive enzyme, the enzyme may play a role in the interconversion between S-malate and fumarate in addition to that between S-citramalate and mesaconate
-
-
-
NATURAL SUBSTRATES
NATURAL PRODUCTS
REACTION DIAGRAM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
(Substrate)
LITERATURE
(Substrate)
COMMENTARY
(Product)
LITERATURE
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
additional information
?
-
-
key enzyme of the mesaconate pathway of (S)-glutamate fermentation
-
-
-
additional information
?
-
Aerobic bacterium
-
constitutive enzyme, the enzyme may play a role in the interconversion between S-malate and fumarate in addition to that between S-citramalate and mesaconate
-
-
-
METALS and IONS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
Fe2+
-
Km for ferrous ammonium sulfate: 0.004 mM; required
Fe2+
-
activates
Fe2+
-
maximal activity at 0.2-0.9 mM
INHIBITORS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
D-malate
-
competitive with L-malate
PCMB
Aerobic bacterium
-
0.15 mM, complete inhibition. 80% protection by 5 mM S-citramalate
ACTIVATING COMPOUND
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
2,3-Dimercapto-1-propanol
-
about half as effective as L-Cys
2-mercaptoethylamine
-
at pH 8.2-8.4 as effective as L-Cys
acetate
-
activity is higher in extracts of cells grown on acetate
D-Cys
-
at pH 8.2-8.4 as effective as L-Cys
DL-homocysteine
-
at pH 8.2-8.4 as effective as L-Cys
L-Cys
-
required. The optimal concentration of L-Cys is 0.5-2.0 mM
sulfhydryl compounds
-
required
KM VALUE [mM]
KM VALUE [mM] Maximum
SUBSTRATE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
2
4
(+)-citramalate
-
-
0.11
-
fumarate
Aerobic bacterium
-
-
2.4
-
L-citramalate
-
-
0.07
-
mesaconate
Aerobic bacterium
-
-
0.45
-
S-citramalate
Aerobic bacterium
-
-
0.56
-
S-malate
Aerobic bacterium
-
-
SPECIFIC ACTIVITY [µmol/min/mg]
SPECIFIC ACTIVITY MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
7.1
-
Aerobic bacterium
-
-
additional information
-
-
of component I and II
pH OPTIMUM
pH MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
6.5
7
-
in presence of Cys
8
8.5
-
in presence of 2-mercaptoethanol
8.5
-
Aerobic bacterium
-
with mesaconate as substrate
8.7
-
Aerobic bacterium
-
with fumarate as substrate
9
-
Aerobic bacterium
-
S-malate as substrate
9.1
-
Aerobic bacterium
-
with S-citramalate as substrate
pH RANGE
pH RANGE MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
5.7
7.7
-
about 50% of maximal activity at pH 7.1 and at pH 9.3, in presence of Cys
7.1
9.3
-
about 50% of maximal activity at pH 7.1 and at pH 9.3, in presence of 2-mercaptoethanol
MOLECULAR WEIGHT
MOLECULAR WEIGHT MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
160000
-
Aerobic bacterium
-
gel filtration
additional information
-
-
the enzyme consists of two components: component I has MW 45000 and component II has MW 310000, determined by gel filtration. A combination of both components gives the active enzyme. At pH 7.5 or below component II partially dissociates into species with molecular weights of about 165000, 82000, and 37000. At pH 9.0 these species reassociate to form active component II of about the original MW. The observed species may represent a monomer, dimer, tetramer and octamer of a single subunit
SUBUNITS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
?
-
the enzyme consists of two components: component I has MW 45000 and component II has MW 310000, determined by gel filtration. A combination of both components gives the active enzyme. At pH 7.5 or below component II partially dissociates into species with molecular weights of about 165000, 82000, and 37000. At pH 9.0 these species reassociate to form active component II of about the original MW. The observed species may represent a monomer, dimer, tetramer and octamer of a single subunit
?
-
enzyme consists of 2 components, neither component alone possesses hydrolase activity, MW of component I: 46000 Da, gel filtration, MW of component I: 310000 Da, gel filtration, 8 * 37000, SDS-PAGE
pH STABILITY
pH STABILITY MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
7
11
-
component I is stable
7
8
-
4C, 48 h, about 20% loss of activity of component II
7.5
-
-
at pH 7.5 or below component II partially dissociates into species with molecular weights of about 165000 Da, 82000 Da, and 37000 Da. At pH 9.0 these species reassociate to form active component II of about the original MW. The observed species may represent a monomer, dimer, tetramer and octamer of a single subunit
TEMPERATURE STABILITY
TEMPERATURE STABILITY MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
37
-
-
2 d, component II is stable in presence of mercaptoethanol, Fe2+, and component I
55
-
-
5 min, component II is stable in presence of mercaptoethanol and Fe2+
GENERAL STABILITY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
freezing and thawing does not significantly decrease the activity of component I, 10-15% loss of activity of component II
-
OXIDATION STABILITY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
4C, 90% loss of activity after 24 h in air. Reactivation by Fe2+ and 2-mercaptoethanol
Aerobic bacterium
-
5667
inactivation by exposure to oxygen, full activation by anaerobic incubation with a sulfhydryl compound for 1-2 hours at 37C
-
5665
inactivation by oxygen. Reactivation by incubating the two protein components with a reducing agent and Fe2+ in absence of oxygen. Mn2+ inhibits activation. Effect of temperature and pH on activation
-
5669
STORAGE STABILITY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
-20C, in presence of 20% (NH4)2SO4 or 10% glycerol in air, about 80-90% can be reactivated even after several months
Aerobic bacterium
-
4C, 70% loss of activity after 1 week under N2
Aerobic bacterium
-
-10C, pH 8.4, protein concentration above 1 mg/ml in 0.1 M Tris-HCl buffer, component I is stable for months
-
-196C, activity of component II remains constant for at least 8 months
-
Purification/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
component I and II
-
component I and II; whole enzyme
-