|
|
||
|
|
|
|
|
UniProt functional annotation for Q89FH0 | ||
|
|
|
|
|
|
||
| UniProt code: Q89FH0. |
|
||
| Organism: | |
Bradyrhizobium diazoefficiens (strain JCM 10833 / BCRC 13528 / IAM 13628 / NBRC 14792 / USDA 110). |
| Taxonomy: | |
Bacteria; Proteobacteria; Alphaproteobacteria; Rhizobiales; Bradyrhizobiaceae; Bradyrhizobium. |
|
||
|
||
| Function: | |
Catalyzes the dehydration of D-tartrate to oxaloacetate. {ECO:0000269|PubMed:17144653}. |
|
||
| Catalytic activity: | |
Reaction=(S,S)-tartrate = H2O + oxaloacetate; Xref=Rhea:RHEA:18289, ChEBI:CHEBI:15377, ChEBI:CHEBI:16452, ChEBI:CHEBI:30927; EC=4.2.1.81; Evidence={ECO:0000269|PubMed:17144653}; |
| Cofactor: | |
Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000269|PubMed:17144653}; Note=Binds 1 Mg(2+) ion per subunit. {ECO:0000269|PubMed:17144653}; |
| Biophysicochemical properties: | |
Kinetic parameters: KM=0.086 mM for D-tartrate {ECO:0000269|PubMed:17144653}; Note=kcat is 7.3 sec(-1) for D-tartrate.; |
| Subunit: | |
Homooctamer; tetramer of dimers. {ECO:0000269|PubMed:17144653}. |
| Miscellaneous: | |
Reaction mechanism is a simple extension of the two-step reaction catalyzed by other members of the family: Lys-184 initiates the reaction by abstraction of the alpha-proton to generate a Mg(2+)- stabilized enediolate intermediate, and the vinylogous beta-elimination of the 3-OH group is general acid-catalyzed by the His-322, accomplishing the anti-elimination of water. The replacement of the leaving group by solvent-derived hydrogen is stereo-random, suggesting that the enol tautomer of oxaloacetate is the product (PubMed:17144653). {ECO:0000305|PubMed:17144653}. |
| Similarity: | |
Belongs to the mandelate racemase/muconate lactonizing enzyme family. {ECO:0000305}. |
Annotations taken from UniProtKB at the EBI.