生物化学 Chap 5 vitamine and coenzyme2

Assignmentforchap4(1)WriteoutthestructureofatrinucleotidecomposedofA,UandC.(2)InDNAofyeastcells,molconcentrationofthymine(T)is32.9%,calculatepercentageconcentrationsofotherbasesinthisDNAmolecule.(3)CompareDNAandRNAintheaspectsofchemicalcompositions,molecularstructureandbiologicalfunctions.(4)WhatisTm?Whatarethecharacteristicsofheatdenaturednucleicacid?vitamineandcoenzymeChap5Classificationofvitamins(Watersolubleandliposolublevitamins)BioactivityandsourcesofdifferentvitaminsImportantcoenzymesandrelativevitaminsintroductionVitamins:theydon’tbelongtoonetypeofcompounds.Buttheyaremicromoleculesthathavesimilarbiologicalfunctions:essentialnutrientsrequiredformetabolisminsmallamounts;can’tbesynthesizedbyhumanbodies;notstructuralcomponents;notenergysource.Toplants,allthevitaminscanbesynthesizedTomicroorganisms,mostofthevitaminsneededcanbesynthesizedMostcoenzymesaremodifiedformsofvitamines.ClassificationofvitaminsWatersolublevitamins(水溶性维生素)VB1VB2VB3VB5VB6VB7VB11VB12(B族维生素)VCLiposolublevitamins（脂溶性维生素）VAVDVEVKSection1watersolublevitaminsVC（ascorbicacid抗坏血酸）Functions:servingasreducertokeepreductivestateofcompoundsincells(eg.–SHinmercaptoenzyme巯基酶；coenzymeofhydroxidase羟化酶)deficiencydisease:scurvy(坏血病)；gumbleedingandtumefying(齿龈出血肿胀);Mainsources:fruitsandvegetableshawthorn山楂300mg/100g;capsicum辣椒100mg/100g;orange桔子30mg/100gVB1（thiamine硫胺素）Bioactiveform:thiaminepyrophosphate/Tpp(焦磷酸硫胺素)Functions:coenzymeofdecarboxylase(脱羧酶);carbohydratemetabolismDeficiencydisease:beriberi(脚气病);inappetence(食欲不振);skinanaesthesia(皮肤麻木)Mainsources:corn,legume(豆类),rice(米糠),yeast(酵母),meat(肉),beansprout(豆芽)VB2（riboflavin核黄素）Bioactiveform:FMN(flavinmononucleotide)黄素单核苷酸;FAD(flavinadeninedinucleotide)黄素腺嘌呤二核苷酸Functions:coenzymesofoxidoreductase(氧化还原酶);carbohydrateandlipidmetabolismDeficiencydisease:growthretardation(生长迟缓);tongueinflammation(舌炎、口角炎);conjunctivitis(结膜炎)Mainsources:corn(米糠),yeast(酵母),liver(肝),kidney(肾),eggyolk(蛋黄),milk,soybeanVB3(pantothenicacid泛酸)Bioactiveform:coenzymeA（CoA辅酶A）Functions:coenzymeofacylcarrierprotein(ACP)(酰基载体蛋白);metabolismoffattyacidsMainsources:yeast,liver,kidney,egg,corn,peanut,milkVB5（niacin烟酸/烟酰胺,VPP）Bioactiveform:NAD(烟酰胺腺嘌呤二核苷酸)NADP（烟酰胺腺嘌呤二核苷酸磷酸）Functions:coenzymeofdehydrogenase(脱氢酶)Deficiencydisease:severediarrhea；tongueinflammation(舌炎、口角炎);pellagra(“癞皮病/糙皮病”)Mainsources:corn,yeast,liver,vegetablesVB6(pyridoxin吡哆素)Bioactiveform:pyridoxalphosphate(磷酸吡哆醛)Functions:coenzymesofaminotransferase(转氨酶)anddecarboxylase(脱羧酶);AAmetabolismDeficiencydisease:diarrhea;dermatitis(皮炎)；tongueinflammation;conjunctivitis(结膜炎)Mainsources:corn,yeast,liver,kidney,eggyolk,milkVB7(biotin生物素、维生素H)Bioactiveform:coenzymeofcarboxylase（羧化酶）Functions:carboxylgroupcarrierDeficiencydisease:dermatitis;muscleache（肌肉疼痛）;lossofappetite（食欲不振）;slightanaemia（轻度贫血）;hairfallingoffMainsources:liver,kidney,eggyolk,yeast,vegetableVB11(folicacid叶酸)Bioactiveform:tetrahydrofolate/CoF(四氢叶酸/辅酶F)Functions:nucleicacidandproteinmetabolismDeficiencydisease:severeanemia(恶性贫血)Mainsources:greenvegetables;yeast,liver,kidneyVB12(钴维素)Bioactiveform:deoxyadenosylcobalamin(脱氧腺苷钴维素)Functions:coenzymeofisomerase(异构酶/变位酶)Deficiencydisease:severeanemia(恶性贫血)；growthretardation(发育不良)Mainsources:liver,egg,meat,milk,fishOnlymicroorganismscansynthesizeVB12.NoVB12inplants.Section2liposolublevitaminsVA(retinol视黄醛）Functions:helpseeingindarkDeficiencydisease:nightblindnessMainsources:fish,meat,carrotExcessintake:skintickling(皮肤瘙痒);hepatomegaly(肝肿大)VDFunctions:tofacilitatetheabsorbanceofcalcium(Ca)andphosphor(P).Deficiencydisease:rachitis(tochildren)佝偻病;bonehyperplasia(骨质疏松)（tooldpeople）Mainsources:liver,egg,milkExcessintake:nausea(恶心);headache;diarrhea;boneovercalcified(过度钙化)VE(tocopherol生育酚)Functions:anti-oxidation;anti-caducity(抗衰老);anticancerDeficiencydisease:slightanemia;yeld;abortionMainsources:plentifulinvegetableoilVKFunctions:cruor(凝血)Deficiencydisease:cruorslowing(凝血迟缓);intestine,stomachanddigestivecanalbleeding（胃肠及消化道出血）Mainsources:greenvegetable;liverMicroorganismsinourintestinecansynthesizeVK.