Thiamine (vitamin B1) is a cofactor for transketolase in the pentose phosphate pathway. Which product of this pathway is directly reduced in thiamine deficiency, impairing fatty acid synthesis and glutathione reduction?
- A Ribose-5-phosphate
- B NADPH ✓
- C NADH
- D ATP
Correct answer: B. NADPH
Explanation
The pentose phosphate pathway generates NADPH, essential for reductive biosynthesis (fatty acid and cholesterol synthesis) and maintaining reduced glutathione via glutathione reductase. Thiamine pyrophosphate is required by transketolase in the non-oxidative branch. While ribose-5-phosphate is also produced, NADPH depletion is the functionally significant consequence in deficiency. NADH is produced in glycolysis and TCA cycle. ATP is not a direct PPP product.
Reference: Lehninger Principles of Biochemistry, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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