This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: vitamins, Subject name: Biochemistry
[{'content': 'Tryptophan is glucogenic & ketogenic by producing \nSelect and explain. \nA. Acetyl CoA & alanine, B. Acetoacetate & fumarate, C. Acetoacetate & arginine, D. Arginine & alanine', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The major metabolic fate of tryptophan is to be oxidized by tryptophan pyrrolase (tryptophan di-oxygenase) (Step 1, Fig. 17.8). It is a hemoprotein. The enzyme is inducible by coicosteroids.iii. In this major pathway, the total 11 carbon atoms of tryptophan are catabolized as formyl group (1C which enters the one-carbon pool), alanine (3C, entering the glucose pathway) and acetoacetate (4C, going to ketogenic pathway). So, tryptophan is both glucogenic and ketogenic. The remaining 3 carbons are removed as 3 CO2 molecules.Ref: DM Vasudevan - Textbook of Biochemistry, 6th edition, page no: 211', 'role': 'assistant'}]