Open Question Type 1: Vitamins → Coenzymes Derivative

Thiamine

Vitamin B1

• Coenzyme: TPP (Thiamine pyrophosphate)

• Function: TPP is a coenzyme for enzymes involved in carbohydrate metabolism, particularly in the decarboxylation of α-keto acids in the TCA cycle and the pentose phosphate pathway

Riboflavin

Vitamin B2

• Coenzyme: FAD (Flavin adenine dinucleotide) and FMN (Flavin mononucleotide)

• Function: FAD and FMN are involved in various redox reactions in the cell, serving as electron carriers in metabolic pathways like the TCA cycle and fatty acid oxidation

Niacin

Vitamin B3

• Coenzyme: NAD (Nicotinamide adenine dinucleotide) and NADP (Nicotinamide adenine dinucleotide phosphate)

• Function: NAD and NADP are involved in redox reactions, serving as electron carriers in metabolic pathways such as glycolysis, TCA cycle, and fatty acid synthesis.

Pantothenic acid

Vitamin B5

• Coenzyme: CoA (Coenzyme A)

• Function: CoA carriers and transfers acyl groups in several metabolic pathways, including TCA cycle, fatty acid synthesis, and the breakdown of carbohydrates and amino acids.

Pyridoxine

Vitamin B6

• Coenzyme: PLP (Pyridoxal phosphate)

• Function:

  • Amino acid metabolism, including transamination and decarboxylation

  • Neurotransmitter synthesis

Biotin

Vitamin B7

• Coenzyme: It is not a coenzyme itself, but serves as a cofactor for enzymes

• Function: It is essential for carboxylation reactions in various metabolic pathways, including fatty acid synthesis, gluconeogenesis, and amino acid metabolism. It helps enzymes add a CO₂ molecule to substrates during these reactions.

Folic acid

Vitamin B9

• Coenzyme: THF (Tetrahydrofolate)

• Function: Transfer of 1-C units in various biosynthetic reactions, including the synthesis of nucleotides (DNA & RNA), amino acids, and certain neurotransmitters

Cobalamin

Vitamin B12

• Coenzyme: Coenzyme B12

• Function: Transfer of a methyl group from N-methyl-THF to homocysteine to yield methionine and to liberate THF

  N-methyl-THF + homocysteine → THF + methionine