system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
All of the following regarding urea cycle is true, except:
assistant
The correct answer is  Carbamoyl phosphate synthase I, the rate-limiting enzyme of the urea cycle, is active only in the presence of N-acetylglutamate, an allosteric activator that enhances the affinity of the synthase for ATP.