复旦大学：《生物化学A Biochemistry》课程PPT教学课件（上）18 维生素与辅酶 Vitamins and Coenzymes（二）

因酸( Nicotinic acid)、烟酰股 NAD+ CoI NADP+ Co l 又称 Vit PP,或抗糙皮病(癞皮病)维生素, 是含N杂环吡啶,体内主要以烟酰胺形式存在。 烟酰胺是Col和CoI的组成成分,(oI为烟酰胺 腺嘌呤二核苷酸 Nicotinamide Adenine Dinucleotide, NA、Co为烟酰胺腺嘌呤二核苷酸磷酸 NIcotinamide Adenine Dinucleotide Phosphate, NADP]。生物体脱氢酶类的辅酶,起携带和传递 氢的作用。 缺乏:引起癜皮病、口腔炎、舌炎、腹痛、腹 泻、痴呆、神经紊乱等

烟酸（Nicotinic Acid）、烟酰胺和 NAD+ [Co I]、NADP+ [Co II] •又称Vit PP，或抗糙皮病（癞皮病）维生素， 是含N杂环吡啶，体内主要以烟酰胺形式存在。 •烟酰胺是CoI和CoII的组成成分，CoI为烟酰胺 腺嘌呤二核苷酸[Nicotinamide Adenine Dinucleotide, NAD]、 CoII为 烟酰胺腺嘌 呤二核苷酸磷酸 [Nicotinamide Adenine Dinucleotide Phosphate, NADP]。生物体脱氢酶类的辅酶，起携带和传递 氢的作用。 •缺乏：引起癞皮病、口腔炎、舌炎、腹痛、腹 泻、痴呆、神经紊乱等

尼克酸 nicotinic aci id尼克酰胺l nicotinamide Ipyridine-3-carboxylic[3-pyridinecarboxylic ac acid amide

烟酸和烟酰胺 尼克酸[nicotinic acid] [pyridine-3-carboxylic acid] 尼克酰胺[nicotinamide] [3-pyridinecarboxylic acid amide]

NicotinIc Add Niacin、 vitamin b3、 niacinamide、 antipellagra vitamin Both form are active the free acid and the amide Sources: organ meat(largest source), fish, yeast, dried fruit, nuts, cereal grains, some vegetables Pellagra-inducing diets: corn meal, corn starch, sweet potatoe, rice, syrup, pork fat

Nicotinic Acid • Niacin、vitamin B3、niacinamide、 antipellagra vitamin. • Both form are active: the free acid and the amide. • Sources: organ meat (largest source), fish, yeast, dried fruit, nuts, cereal grains, some vegetables. • Pellagra-inducing diets: corn meal, corn starch, sweet potatoe, rice, syrup, pork fat

BiocheicalFunction NH2 NH, NAD+ NADH +H+ or NADP+ or NadPh+h+ In the older literature nad+ is referred to as DPN or coenzyme l, NADP+ is referred to as TPN or coenzymeⅢ

Biochemical Function N C N H2 O N C N H2 H H O NAD+ or NADP+ + H+ NADH + H+ or NADPH + H+ In the older literature NAD+ is referred to as DPN or coenzyme I，NADP+ is referred to as TPN or coenzyme II

▲ HH H NH NH NH2 +H 2H. N CH, O R Aside R Bside HH 0=P-OH NADH (reduced) OHOH NH2 n Adenine O—CH2O HH NAD+ (oxidized) OH OH In NAdP this hydroxyl group is esterified with phosphate. (a)

NADH和NADPH

NADH的紫外吸收 1.0 Oxidized 0.8 (NADT) 0.6 0.4 Reduced (NADH) 0.2 0.0 220240260280300320340360380 Wavelength(nm) (b)

NAD+/NADH的紫外吸收

以NAD和NADP Stereochemical specificity for nicotinamide Enzyme Coenzyme ring(A or B) Isocitrate dehydrogenase NAD A a-Ketoglutarate dehydrogenase NAD+ B Glucose b-pi hosphate dehydrogenase NADP B Malate dehydrogenase NAD Glutamate dehydrogenase NAD or NADP+ B Glyceraldehyde 3-phosphate dehydrogenase NAD B Lactate dehydrogenase NAD A Alcohol dehydrogenase NAD A

以NAD+和NADP+为 辅酶的脱氢酶

迟缓、发育停滞、脂 肪肝以及包括溃疡在内的胃肠紊乱 。 尼克酰胺能抑制胰腺癌的发展, 给仓鼠注射致胰腺癌物后,给以尼 克酰胺治疗,发现癌症的发展受到 卯制。尼克酰胺与叶酸一样能刺激 受损的DNA的修复

烟酸的作用 •缺乏：生长迟缓、发育停滞、脂 肪肝以及包括溃疡在内的胃肠紊乱 --黑舌病。 •尼克酰胺能抑制胰腺癌的发展， 给仓鼠注射致胰腺癌物后，给以尼 克酰胺治疗，发现癌症的发展受到 抑制。尼克酰胺与叶酸一样能刺激 受损的DNA的修复

椭病【 Pellagra】 Early stages Anorexia(厌食) Indigestion(消化不良) Muscle weakness(肌无力) Reddened skin(红皮肤) Rough skin(皮肤粗糙) Advanced stages °3 D's of pellagra: Dermatitis(皮炎), Diarrhea(腹泻), Dementia(痴呆)

糙皮病【Pellagra】 • Early stages: • Anorexia（厌食） • Indigestion（消化不良） • Muscle weakness（肌无力） • Reddened skin（红皮肤） • Rough skin（皮肤粗糙） • Advanced stages • 3 D’s of pellagra: Dermatitis（皮炎）, Diarrhea（腹泻）, Dementia（痴呆）

Tryptophan can substitute for niacin: 60 mg of tryptophan is equivalent to 1 mg of niacin; 60 gm of protein contains 600 mg of tryptophan which then represent 10 mg of niacin TRYPTOPHAN FORMYLKYNURENINE KYNURENINE 甲酰犬尿氨酸 血管紧张肽原酶 3-HYDROXYANTHRANILIC ACID 3-HYDROXYKYNURENINE 3羟基氨基苯甲酸 3羟基犬尿氨酸 B6-de pe ndent reac NICOTINIC ACID

Sparing Action of Tryptophan TRYPTOPHAN FORMYLKYNURENINE KYNURENINE 3-HYDROXYKYNURENINE 3-HYDROXYANTHRANILIC ACID NICOTINIC ACID B6-dependent reaction Tryptophan can substitute for niacin: 60 mg of tryptophan is equivalent to 1 mg of niacin; 60 gm of protein contains 600 mg of tryptophan which then represent 10 mg of niacin。 甲酰犬尿氨酸 血管紧张肽原酶 3-羟基犬尿氨酸 3-羟基氨基苯甲酸