Which water-soluble vitamin is essential for hemoglobin synthesis by supporting heme formation?

• A. Vitamin B6 (pyridoxine)
• B. Vitamin C (ascorbic acid)
• C. Folate (vitamin B9)
• D. Vitamin B12 (cobalamin)

Answer: (A)

Verified step by step guidance

1. Understand the role of water-soluble vitamins in hemoglobin synthesis, focusing on their involvement in heme formation and red blood cell production.
2. Recall that heme is the iron-containing component of hemoglobin, and its synthesis requires specific enzymes that depend on certain vitamins as cofactors.
3. Identify which vitamin acts as a coenzyme in the enzymatic reactions that lead to the formation of heme, particularly in the synthesis of delta-aminolevulinic acid (ALA), the first step in heme production.
4. Recognize that Vitamin B6 (pyridoxine) is essential because it serves as a coenzyme for ALA synthase, the enzyme catalyzing the initial step in heme synthesis.
5. Compare the roles of the other vitamins listed (Vitamin C, Folate, Vitamin B12) to confirm that while they are important for other aspects of blood health, they do not directly support heme formation.