Vitamins and Nutrition Vitamin Coenzyme Cofactor Prosthetic group Water Soluble Vitamins Name Vitamin B1 thiamin Vitamin B2 riboflavin Function Precursor to coenzyme thiamin pyrophosphate which is required for oxidative decarboxylation reactions Precursor to FAD and FMN which are prosthetic groups used for redox reactions Vitamin B3 niacin Precursor to NAD and NADP which are coenzymes used for redox reactions Vitamin B5 Pantothenic acid Vitamin B6 pyridoxal and related compounds Vitamin B12 cobalamin Folic acid Precursor to Coenzyme A Biotin Prosthetic group for several carboxylase enzymes Vitamin C ascorbic acid Coenzyme for hydroxylase enzymes Deficiency Beriberi muscle weakness loss of reflexes numbness depression Not named photophobia proliferation of capillaries in the eye dermatitis Pellegra weight loss digestive disorders dermatitis depression dementia Not named neurological and digestive problems Precursor to pyridoxal phosphate which is a prosthetic group for amino acid metabolic enzymes and for glycogen phosphorylase Not named dermatitis neuropathy altered free amino acid levels depression Precursor to coenzymes used for one carbon transfer reactions Pernicious anemia enlarged fragile erythrocytes neurological disorders Precursor to coenzyme tetrahydrofolate which is used for one carbon transfer reactions Megaloblastic anemia enlarged fragile erythrocytes neural tube defects neurological disorders Not named depression hallucinations muscle pain dermatitis immunodeficiency Scurvy defective collagen synthesis dementia Fat Soluble Vitamins Name Function Vitamin A Precursor visual pigment retinal and to retinoic acid signaling molecules involved in cellular retinol and differentiation carotene Vitamin D ergocalciferol and cholecalciferol Vitamin E tocopherol Vitamin K menadione and related compounds Precursor to 1 25 dihydroxyvitamin D a signaling molecule involved in calcium absorption and homeostasis and in regulation of cellular differentiation Antioxidant especially in erythrocytes Precursor to Vitamin K coenzyme used for synthesis of carboxyglutamate residues especially in clotting factor proteins Deficiency Not named night blindness blindness developmental abnormalities keratinization of epithelial tissues Rickets and Osteomalacia softening of the bones Not named anemia and possibly other effects Hemorrhagic disease of the newborn Hemorrhagic syndrome deficient blood clotting Niacin Vitamin B3 O HNO3 N Nicotine H N O OH CH3 N Nicotinic acid N NH NH2 O NH2 NH3 O Isoniazid N O N O O NH2 NH2 N CH2 O OH O P O OH OH O O P O CH2 O OH OH 2 electrons 1 proton O H H NH2 N R Oxidized NAD P O O P O Nicotinamide adenine O dinucleotide 2 phosphate NADP Nicotinamide adenine dinucleotide NAD H N N O P O CH2 O O O OH N N O P O N N O OH NH2 O N N N CH2 O NH2 O Nicotinamide NH2 N 2 electrons 1 proton O R Reduced NAD P H Alcohol Dehydrogenase His67 His67 HN Cys46 Cys174 N His51 Ser48 Cys46 S O Substrate binding H Zn O H3C C H Ser48 S S N Zn Cys174 N NH OH S His51 HN NH N O H O H H H OH N O H H R NH2 O His67 His51 HN Cys46 S Proton abstraction His67 N Cys46 Ser48 S Zn H H O O H3C C O HH H Zn H OH N H3C C S H Ser48 S Hydride transfer O Cys174 N NH N O His51 HN Cys174 H N O H OH N O H H R NH2 O Substrate dissociation His67 HN Cys46 S Cys174 N His51 Ser48 NH OH S Zn O H H N H O R O NH NH2 Riboflavin Vitamin B2 O H3C N H3C N O NH N O H3C N H3C N NH N OH HO HO OH Riboflavin Vitamin B2 1 electron 1 proton O H3C N NH N R Fully oxidized N H3C N NH N O 1 electron 1 proton O OH HO OH OH NH2 O O O P O O P O O O N N N N O P O CH2 O O Flavin mononucleotide FMN Isoalloxazine Ring N O H3C OH OH H3C O H H3C N H3C N Flavin adenine dinucleotide FAD 1 electron 1 proton O NH N R Partially reduced O OH H OH O H3C N H3C N N R H 1 electron 1 proton NH Fully reduced Ascorbic Acid Vitamin C 2 electrons 2 protons OH O HO HO Ascorbic acid Vitamin C O HO O OH OH 2 electrons 2 protons O O O Dehydroascorbic acid O Thiamin Vitamin B1 NH2 H N N N H3C NH2 Thiamin Vitamin B1 S N OH H3C H N N H3C Thiamin pyrophosphate S O O O P O P O H3C O O HO NH2 N H3C N N Thiamin pyrophosphate H S O N O O P O P O H3C O Thiamin pyrophosphate carbanion NH2 N H3C N C S O O O Pyruvate H3C C C O C N O O P O P O H3C O NH2 N H3C N S Hydroxyethyl Thiamin pyrophosphate O O O P O P O H3C O CH3 O O CO2 H O Pantothenic Acid Vitamin B5 N N O OH Pantoic acid O N N O H3C C CH3 OH H3C C CH3 O C NH O OH CH2 HO CH O C O C NH NH O H2C CH2 Pantothenic Acid Vitamin B5 OH H3C C CH3 HO CH H2C CH2 C OH N N O O CH2 HO CH O O P O P O CH2 O O O N N O P O P O CH2 O CH2 alanine NH2 NH2 H C N CH2 CH2 SH OH O O H2C CH2 H C CH3 C N CH2 CH2 S Acetyl Coenzyme A Acetyl CoA Coenzyme A CoA SH Biotin O HN NH H H S O Biotin H HN O NH H OH H S H O O N H Lys Enzyme O O Carboxylase prosthetic group C N Carboxybiotin NH H H S H O N H Lys Enzyme Folic Acid H2N N Folic Acid N HN N O HN p Amino benzoic acid O N10 O N NADPH N HN N O O H N N5 HN Glutamate O O H NADP H2N N N HN Dihydrofolate reductase O H NADP H2N HN N H N O R H HO N O NH2 NH2 CH3 O Co3 N O N HN N O O P O O N O HN O HO N O N O N NH2 O HN N O O P O O HO N O Cyanocobalamin Vitamin B12 Co3 O O HO O NH2 N N O N N O P O NH2 O NH2 NH2 O O HO N Co3 N NH2 H2N NH2 N N O NH2 NH2 O CH2 O O H2N NH2 N N NH2 NH2 O O H2N O O NH2 N N O C HO R N HO NH2 HN Tetrahydrofolate THF Dihydrofolate Cobalamin Vitamin B12 O H H N HN Dihydrofolate reductase N R Folic Acid H NADPH H Methylcobalamin O HO 5 Deoxyadenosylcobalamin Vitamin B6 O HO CH HO HO N CH3 N H H Pyridoxal Pyridoxine CH2 HO OH OH CH3 H2N CH2 CH3 OH N H Pyridoxamine O R O CH HO N O O P O CH3 O HO O P O CH3 H O N H Pyridoxal …