This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pharmacology
[{'content': 'Azaserine inhibits \nSelect and explain. \nA. Glycinamide ribonucleotide synthetase, B. Glycinamide ribonucleotide transformylase, C. Formyl glycinamide ribonucleotide amidotransferase, D. Inosine monophosphate synthase', 'role': 'user'}, {'content': 'Answer: C \nExplanation: In de novo synthesis of purine nucleotides, there are 10 steps.The 4th step (addition of N3) is catalysed by the enzyme Formyl glycinamide ribonucleotide amidotransferase.This enzyme is inhibited by azaserine, an anticancer drug.', 'role': 'assistant'}]