2017_enzyme_1&2(1).pptxVIP免费

1Enzymeschunguangwang@tongji.edu.cn2017-10-17王春光2ThinkaboutyourbreakfastIfeaten,digestedinhours;Ifnoteaten,stayforyears…..3Orotatedecarboxylaseknon=2.810-16s-178106yearkcat=39s-12510-3secondkcat/knon=1.41017Enzymesarebiologicalcatalysts.酶是生物催化剂。Enzymesaffectreactionrates,notequilibria.酶只影响反应速度，而不影响反应平衡。4Whydopeoplestudyenzymes?Science&Technology5Enzyme-inhibitorexamplesLipaseinhibitor;Acetylcholinesteraseinhibitor.乙酰胆碱酯酶抑制剂Anti-AIDScock-tailtherapy;6①Indiancurare②Organophosphorus③AD-treatingmedicineacetylcholineacetylcholinesterase①②③7Howdoenzymeswork?8VNQHLCGSHLVEALYLVCGERGVNQHLCGSHLVEALYLVCGERGchymotrypsin….NH-CH-COOHNH2-CH-CO-….Substrate底物Product产物Chymotrypsin胰凝乳蛋白酶….NH-CH-CONH-CH-CO-….chymotrypsin9Chymotrypsin胰凝乳蛋白酶(PDB7GCH)10Chymotrypsin胰凝乳蛋白酶Activesite活性位点11Catalytictriad:Ser195,His57,Asp102.Inhibitor抑制剂Chymotrypsin胰凝乳蛋白酶12(juang.bst.ntu.edu.tw/BCbasics/Animation1.htm)Chymotrypsin胰凝乳蛋白酶131415No.ClassTypeofreactioncatalyzed1Oxidoreductase氧化还原酶Transferofelectrons2Transferase转移酶Grouptransferreaction3Hydrolase水解酶Hydrolysisreaction4Lyase裂合酶Additionofgroupstodoublebonds,orformationofdoublebondsbyremovalofgroups5Isomerase异构酶Transferofgroupswithinmoleculestoyieldisomericforms6Ligase连接酶BondformationcoupledwithATPhydrolysisInternationalclassificationofenzymesSerineendopeptidase:ChymotrypsinTrypsinSubtilisin……EC3.4.21.1EC3.4.21.4EC3.4.21.6216APFirstorderreactionZeroorderreactionSecondorderreactionA+BP]A[kvkv]B][A[kv17APdtddtdv[P][A]sLMolv:sk1:dtkd]A[[A]0]Aln[[A]lnkta-kt]A[k-kte]A[[A]018AP]A[[A]kdtdvWhen[A]=[A]0,v=V0When[A]=[A]/2,t=t1/2Radioactiveisotopedecomposition:Slope=V0V0:initialvelocity(initialrate).t1/2:half-lifetime.32Pt1/214days;125It1/260days.19APPEnzymeA???20PEnzymeAS+EP+ES+EESP+E1k1k2k2kS+EESP+E1k1k2k21Slope=V0initialperiodcompletereaction22S+EESP+E1...