Type 1 glutamine amidotransferase (GATase1)-like domain found in cyanophycinase
Type 1 glutamine amidotransferase (GATase1)-like domain found in cyanophycinase. This group contains proteins similar to the extracellular cyanophycinases from Pseudomonas anguilliseptica BI (CphE) and Synechocystis sp. PCC 6803 CphB. Cyanophycinases are intracellular exopeptidases which hydrolyze the polymer cyanophycin (multi L-arginyl-poly-L-aspartic acid) to the dipeptide beta-Asp-Arg. Cyanophycinase is believed to be a serine-type exopeptidase having a Ser-His-Glu catalytic triad which differs from the Cys-His-Glu catalytic triad typical of GATase1 domains by having a Ser in place of the reactive Cys at the nucleophile elbow.