In enzymology, a (carboxyethyl)arginine ò-lactam-synthase () is an enzyme that catalyzes the chemical reaction
Thus, the two substrates of this enzyme are ATP and L-N2-(2-carboxyethyl)arginine, whereas its 3 products are AMP, diphosphate, and deoxyamidinoproclavaminate.
This enzyme belongs to the family of ligases, specifically the cyclo-ligases, which form carbon-nitrogen bonds. The systematic name of this enzyme class is L-N2-(2-carboxyethyl)arginine cyclo-ligase (AMP-forming). This enzyme is also called L-2-N-(2-carboxyethyl)arginine cyclo-ligase (AMP-forming). This enzyme participates in clavulanic acid biosynthesis.