Vitamin Name/Pathway(s),Enzyme(s)

Question 1

Thiamine (B1)

Answer 1

• PDH, TCA cycle, HMP shunt, metabolism of valine, isoleucine and leucine
• Pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase, Transketolase, branched chain ketoacid dehydrogenase

Question 2

Riboflavin (B2) (FAD[H2])

Answer 2

• Many pathways

- Dehydrogenases

Question 3

Niacin (B3) (NAD[H]) (NADP[H])

Answer 3

• Many pathways

- Dehydrogenases

Question 4

Pantothenic acid CoA (B5)

Answer 4

• Fatty acid metabolism, PDH, TCA cycle

- Fatty acid synthase, Fatty acyl CoA synthetase, pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase

Question 5

Pyridoxine (B6)

Pyridoxal-P (PLP)

Answer 5

• Protein catabolism, heme synthesis

- Aminotransferases (transaminases): AST (GOT), ALT (GPT), and delta-aminolevulinate synthase

Question 6

Biotin (B7)

Answer 6

• Gluconeogenesis, fatty acid synthesis, odd-carbon fatty acid synthesis
• Pyruvate carboxylase, Acetyl CoA carboxylase, Propionyl CoA carboxylase

Question 7

Folate (B9)

Answer 7

• Thymidine synthesis, purine synthesis

- Thymidylate synthase, other enzymes in purine synthesis

Question 8

Cyanocobalamin (B12)

Answer 8

• Methionine, SAM, Odd-carbon fatty acid synthesis

- Homocysteine methyltransferase, Methylmalonyl CoA mutase

Question 9

Ascorbate (C)

Answer 9

• Collagen synthesis, catecholamine synthesis, absorption of iron in GI tract
• Propyl and lysyl hydroxylases, dopamine hydroxylase