Hydrogenobyrinic acid a,c-diamide synthase (glutamine-hydrolysing)

In enzymology, a hydrogenobyrinic acid a,c-diamide synthase (glutamine-hydrolysing) (EC 6.3.5.9) is an enzyme that catalyzes the chemical reaction

2 ATP + hydrogenobyrinic acid + 2 L-glutamine + 2 H₂O

\rightleftharpoons

2 ADP + 2 phosphate + hydrogenobyrinic acid a,c-diamide + 2 L-glutamate

The 4 substrates of this enzyme are ATP, hydrogenobyrinic acid, L-glutamine, and H₂O, whereas its 4 products are ADP, phosphate, hydrogenobyrinic acid a,c-diamide, and L-glutamate.

This enzyme belongs to the family of ligases, specifically those forming carbon-nitrogen bonds carbon-nitrogen ligases with glutamine as amido-N-donor. The systematic name of this enzyme class is hydrogenobyrinic-acid:L-glutamine amido-ligase (AMP-forming). This enzyme is also called CobB. This enzyme participates in porphyrin and chlorophyll metabolism.

References

Debussche L, Thibaut D, Cameron B, Crouzet J, Blanche F (1990). "Purification and characterization of cobyrinic acid a,c-diamide synthase from Pseudomonas denitrificans". J. Bacteriol. 172 (11): 6239–44. PMC 526805. PMID 2172209.
Warren MJ, Raux E, Schubert HL, Escalante-Semerena JC (2002). "The biosynthesis of adenosylcobalamin (vitamin B12)". Nat. Prod. Rep. 19 (4): 390–412. doi:10.1039/b108967f. PMID 12195810.

Enzymes: CO CS and CN ligases (EC 6.1-6.3)

6.1: Carbon-Oxygen	Aminoacyl tRNA synthetase Alanine Arginine Asparagine Aspartate Cysteine D-alanine—poly(phosphoribitol) ligase Glutamate Glutamine Glycine Histidine Isoleucine Leucine Lysine Methionine Phenylalanine Proline Serine Threonine Tryptophan Tyrosine Valine

6.2: Carbon-Sulfur	Succinyl coenzyme A synthetase Acetyl—CoA synthetase Long-chain-fatty-acid—CoA ligase

6.3: Carbon-Nitrogen	Glutamine synthetase Ubiquitin ligase Cullin Von Hippel–Lindau tumor suppressor UBE3A Mdm2 Anaphase-promoting complex UBR1 Glutathione synthetase CTP synthetase Adenylosuccinate synthase Argininosuccinate synthase Holocarboxylase synthetase GMP synthase Asparagine synthetase Carbamoyl phosphate synthetase I II Glutamate–cysteine ligase

Enzymes

Activity	Active site Binding site Catalytic triad Oxyanion hole Enzyme promiscuity Catalytically perfect enzyme Coenzyme Cofactor Enzyme catalysis Enzyme kinetics Lineweaver–Burk plot Michaelis–Menten kinetics

Regulation	Allosteric regulation Cooperativity Enzyme inhibitor

Classification	EC number Enzyme superfamily Enzyme family List of enzymes

Types	EC1 Oxidoreductases(list) EC2 Transferases(list) EC3 Hydrolases(list) EC4 Lyases(list) EC5 Isomerases(list) EC6 Ligases(list)

This article is issued from Wikipedia - version of the Thursday, March 31, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.