This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
[{'content': 'NAD acts as a cofactor for all except \nSelect and explain. \nA. Isocitrate dehydrogenase, B. Alpha ketoglutarate dehydrogenase, C. Malate dehydrogenase, D. Succinyl thiokinase', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Niacin (Vitamin B3) in biologically active form of NAD+ (nicotinamide adenine dinucleotide) and NADP+ (nicotinamide, adenine dinucleotide phosphate) act as cofactor for various enzymes such as\nNADP+ Cofactor\n\nGlucose-6-phosphate dehydrogenase (G-6-PD (glucose-6-PO4 to 6-phosphogluconate)\nGlutathione reductase\n\nEither NADP+\xa0or NAD+ \xa0Cofactor\n\n\nGlutamate dehydrogenase (glutamate → α-ketoglutarate + NH3)\nIsocitrate dehydrogenase (isocitrate → oxalosuccinate)\xa0\n\nNAD+ Cofactor\n\nMalate dehydrogenase (malate → oxaloacetate)\nAlcohol dehydrogenase (ethanol → acetaldehyde\nLactate dehydrogenase (pyruvic acid → lactic acid)\nGlyceraldehyde-3-phosphate dehydrogenase (glyceraldehyde 3P →1, 3 diphosphoglycerate)\nα - Glycero-P-dehydrogenase\nα -Ketoglutarate dehydrogenase (α – ketoglutarate → CoA)\nPyruvate dehydrogenase complex (PDC) (pyruvate →\xa0 CoA)', 'role': 'assistant'}]