Biochemistry Urea cycle 5f70fb50 Allosteric activator of NAG synthase is: A Aspaate B Arginine C CPS-I D CPS-II High-Yield Explanation NAG is an allosteric activator of CPS-I (rate limiting enzyme) NAG is synthesized from N-acetyl glutamate synthase or NAG synthase, for which arginine is the activator.