UniProt functional annotation for Q05514



	UniProt functional annotation for Q05514

UniProt code: Q05514.

Organism: Clostridium tetanomorphum.

Taxonomy: Bacteria; Firmicutes; Clostridia; Eubacteriales; Clostridiaceae; Clostridium.

Function: Involved in the methylaspartate cycle. Catalyzes the formation of the alpha,beta-unsaturated bond by the reversible anti elimination of ammonia from L-threo-beta-methylaspartate (L-threo- (2S,3S)-3-methylaspartate) to give mesaconate. It can also use L- erythro-beta-methylaspartate (L-erythro-(2S,3R)-3-methylaspartate), L- aspartate, fumarate and ethylfumarate as substrates. {ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200, ECO:0000269|PubMed:22614383}.

Catalytic activity: Reaction=(2S,3S)-3-methyl-L-aspartate = mesaconate + NH4(+); Xref=Rhea:RHEA:12829, ChEBI:CHEBI:28938, ChEBI:CHEBI:36986, ChEBI:CHEBI:58724; EC=4.3.1.2; Evidence={ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200, ECO:0000269|PubMed:22614383};

Cofactor: Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000269|PubMed:11748244, ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:22614383};

Activity regulation: Inhibited by calcium ions. {ECO:0000269|PubMed:13630903}.

Biophysicochemical properties: Kinetic parameters: KM=0.65 mM for L-threo-beta-methylaspartate (with 4 mM of KCl at pH 9.76 and at 25 degrees Celsius) {ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200}; KM=0.67 mM for L-threo-beta-methylaspartate (with 50 mM of KCl at pH 9 and at 30 degrees Celsius) {ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200}; KM=0.7 mM for mesaconate (with 20 mM of MgCl(2) at pH 9 and at 30 degrees Celsius) {ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200}; KM=1 mM for L-threo-beta-methylaspartate (with 20 mM of MgCl(2) at pH 9 and at 30 degrees Celsius) {ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200}; KM=2.3 mM for L-aspartate (with 4 mM of KCl at pH 9.76 and at 25 degrees Celsius) {ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200}; KM=2.8 mM for L-threo-beta-methylaspartate (with 0.3 mM of KCl at pH 9 and at 30 degrees Celsius) {ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200}; Vmax=2089 umol/min/mg enzyme with L-threo-beta-methylaspartate as substrate (with 50 mM of KCl at pH 9 and at 30 degrees Celsius) {ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200}; Vmax=309 umol/min/mg enzyme with L-threo-beta-methylaspartate as substrate (with 0.3 mM of KCl at pH 9 and at 30 degrees Celsius) {ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200}; Vmax=266 umol/min/mg enzyme with L-threo-beta-methylaspartate as substrate (with 4 mM of KCl at pH 9.76 and at 25 degrees Celsius) {ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200}; Vmax=2.5 umol/min/mg enzyme with L-erythro-beta-methylaspartate as substrate (with 4 mM of KCl at pH 9.76 and at 25 degrees Celsius) {ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200}; Vmax=2.4 umol/min/mg enzyme with L-aspartate as substrate (with 4 mM of KCl at pH 9.76 and at 25 degrees Celsius) {ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200}; Note=Kcat is 61 sec(-1) for amination of mesaconate (with 20 mM of MgCl(2) at pH 9 and at 30 degrees Celsius). Kcat is 89 sec(-1) for deamination of L-threo-beta-methylaspartate (with 20 mM of MgCl(2) at pH 9 and at 30 degrees Celsius).; pH dependence: Optimum pH is 9.7. {ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200}; Temperature dependence: Optimum temperature is 55 degrees Celsius. It retains only half of its original activity after a 30 minutes incubation period at 50 degrees Celsius. {ECO:0000269|PubMed:13630903, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200};

Pathway: Amino-acid degradation; L-glutamate degradation via mesaconate pathway; acetate and pyruvate from L-glutamate: step 2/4.

Subunit: Homodimer. {ECO:0000269|PubMed:11748244, ECO:0000269|PubMed:1420191, ECO:0000269|PubMed:19670200, ECO:0000269|PubMed:22614383}.

Similarity: Belongs to the methylaspartate ammonia-lyase family. {ECO:0000305}.

Annotations taken from UniProtKB at the EBI.


Organism:		Clostridium tetanomorphum.
Taxonomy:		Bacteria; Firmicutes; Clostridia; Eubacteriales; Clostridiaceae; Clostridium.



Function:		Involved in the methylaspartate cycle. Catalyzes the formation of the alpha,beta-unsaturated bond by the reversible anti elimination of ammonia from L-threo-beta-methylaspartate (L-threo- (2S,3S)-3-methylaspartate) to give mesaconate. It can also use L- erythro-beta-methylaspartate (L-erythro-(2S,3R)-3-methylaspartate), L- aspartate, fumarate and ethylfumarate as substrates. {ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200, ECO:0000269\|PubMed:22614383}.


Catalytic activity:		Reaction=(2S,3S)-3-methyl-L-aspartate = mesaconate + NH4(+); Xref=Rhea:RHEA:12829, ChEBI:CHEBI:28938, ChEBI:CHEBI:36986, ChEBI:CHEBI:58724; EC=4.3.1.2; Evidence={ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200, ECO:0000269\|PubMed:22614383};
Cofactor:		Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000269\|PubMed:11748244, ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:22614383};
Activity regulation:		Inhibited by calcium ions. {ECO:0000269\|PubMed:13630903}.
Biophysicochemical properties:		Kinetic parameters: KM=0.65 mM for L-threo-beta-methylaspartate (with 4 mM of KCl at pH 9.76 and at 25 degrees Celsius) {ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200}; KM=0.67 mM for L-threo-beta-methylaspartate (with 50 mM of KCl at pH 9 and at 30 degrees Celsius) {ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200}; KM=0.7 mM for mesaconate (with 20 mM of MgCl(2) at pH 9 and at 30 degrees Celsius) {ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200}; KM=1 mM for L-threo-beta-methylaspartate (with 20 mM of MgCl(2) at pH 9 and at 30 degrees Celsius) {ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200}; KM=2.3 mM for L-aspartate (with 4 mM of KCl at pH 9.76 and at 25 degrees Celsius) {ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200}; KM=2.8 mM for L-threo-beta-methylaspartate (with 0.3 mM of KCl at pH 9 and at 30 degrees Celsius) {ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200}; Vmax=2089 umol/min/mg enzyme with L-threo-beta-methylaspartate as substrate (with 50 mM of KCl at pH 9 and at 30 degrees Celsius) {ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200}; Vmax=309 umol/min/mg enzyme with L-threo-beta-methylaspartate as substrate (with 0.3 mM of KCl at pH 9 and at 30 degrees Celsius) {ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200}; Vmax=266 umol/min/mg enzyme with L-threo-beta-methylaspartate as substrate (with 4 mM of KCl at pH 9.76 and at 25 degrees Celsius) {ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200}; Vmax=2.5 umol/min/mg enzyme with L-erythro-beta-methylaspartate as substrate (with 4 mM of KCl at pH 9.76 and at 25 degrees Celsius) {ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200}; Vmax=2.4 umol/min/mg enzyme with L-aspartate as substrate (with 4 mM of KCl at pH 9.76 and at 25 degrees Celsius) {ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200}; Note=Kcat is 61 sec(-1) for amination of mesaconate (with 20 mM of MgCl(2) at pH 9 and at 30 degrees Celsius). Kcat is 89 sec(-1) for deamination of L-threo-beta-methylaspartate (with 20 mM of MgCl(2) at pH 9 and at 30 degrees Celsius).; pH dependence: Optimum pH is 9.7. {ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200}; Temperature dependence: Optimum temperature is 55 degrees Celsius. It retains only half of its original activity after a 30 minutes incubation period at 50 degrees Celsius. {ECO:0000269\|PubMed:13630903, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200};
Pathway:		Amino-acid degradation; L-glutamate degradation via mesaconate pathway; acetate and pyruvate from L-glutamate: step 2/4.
Subunit:		Homodimer. {ECO:0000269\|PubMed:11748244, ECO:0000269\|PubMed:1420191, ECO:0000269\|PubMed:19670200, ECO:0000269\|PubMed:22614383}.
Similarity:		Belongs to the methylaspartate ammonia-lyase family. {ECO:0000305}.