Reaction: O-carbamoyl-L-serine + H2O = pyruvate + 2 NH3 + CO2 (overall reaction)
(1a) O-carbamoyl-L-serine = CO2 + NH3 + 2-aminoprop-2-enoate
(1b) 2-aminoprop-2-enoate = 2-iminopropanoate (spontaneous)
(1c) 2-iminopropanoate + H2O = pyruvate + NH3 (spontaneous)
Other name(s): O-carbamoyl-L-serine deaminase; carbamoylserine deaminase; O-carbamoyl-L-serine ammonia-lyase (pyruvate-forming)
Systematic name: O-carbamoyl-L-serine ammonia-lyase (decarboxylating; pyruvate-forming)
Comments: A pyridoxal-phosphate protein. The enzyme cleaves a carbon-oxygen bond, releasing CO2, ammonia, and an unstable enamine product that tautomerizes to an imine form, which undergoes a hydrolytic deamination to form pyruvate and a second ammonia molecule. The latter reaction, which can occur spontaneously, can also be catalysed by EC 3.5.99.10, 2-iminobutanoate/2-iminopropanoate deaminase.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 52227-64-2
References:
1. Cooper, A.J.L. and Meister, A. Enzymatic conversion of O-carbamyl-L-serine to pyruvate and ammonia. Biochem. Biophys. Res. Commun. 55 (1973) 780-787. [PMID: 4761084]