Molecular identification of carnosine synthase as ATP-grasp domain-containing protein 1 (ATPGD1).

ABSTRACT: Carnosine (beta-alanyl-L-histidine) and homocarnosine (gamma-aminobutyryl-L-histidine) are abundant dipeptides in skeletal muscle and brain of most vertebrates and some invertebrates. The formation of both compounds is catalyzed by carnosine synthase, which is thought to convert ATP to AMP and inorganic pyrophosphate, and whose molecular identity is unknown. In the present work, we have purified carnosine synthase from chicken pectoral muscle about 1500-fold until only two major polypeptides of 100 and 90 kDa were present in the preparation. Mass spectrometry analysis of these polypeptides did not yield any meaningful candidate. Carnosine formation catalyzed by the purified enzyme was accompanied by a stoichiometric formation, not of AMP, but of ADP, suggesting that carnosine synthase belo

SUBMITTER: Drozak J 

PROVIDER: S-EPMC2843183 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature