生物化学试题2006秋季卷

生物化学I（2006年秋季学期A卷 IV《中山大学授予学 “ ”简答题（共25小题，每小题4分50分以50分计入总分哪些标准氨基酸含两个手性碳原子？写出它们的Fisher为什么SDS变性电泳可以估算蛋白质的分子量Massspectroscopy在生物大分子研究中有什么应用-Keratin、Collagen、Silkfibroin的二级结构和氨基酸组成有何特点invivoHemoglobin与O2的亲和力增加图示抗体的一般结构（包括结构域及可能的二硫键写出蛋白质氨基酸的基本步骤。什么是酶催化的过渡态理论？列出你所知道的支持酶的可逆抑制剂有几类？它们的抑制动力学各有何特点细胞膜表面的Glycoprotein和GlycolipidDNA膜脂的分类及其结构特点图示secondaryactivetransport，uniport，symport，antiport.Acetylcholinereceptor通道是如何控制开关的K＋离子通道是如何对通过的离子进行选择的膜电位是怎样控制Na＋通道开关的（可图示并说明Ca2+泵和Na+-K+泵的异同点。Youhaveacrudelysatesamplecontainingamixtureofsixproteins(1,2,3,4,5,andβ-galactosidase).Somecharacteristicsoftheseproteinsareshowninthetablebelow.Giveanavailableprocedureofpurifyingβ-galactosidase.(10pts)ConcentrationofammoniumrequiredforWeightpoint12345- Youareworkingonacompoundasapotentialdrugthatinhibitsanoverproducedenzymewhoseuncontrolledactivityleadstouncontrolledcellproliferation(cancer).Asteady-statekineticysisoftheenzyme-catalyzedreactionwascarriedout,withvelocitiesmeasuredasafunctionoftheconcentrationofthesubstrateintheabsenceandinthepresenceof10nMinhibitor.Theresultsofthekineticsexperimentareplottedforyoubelow.Pleaseanswerthefollowingquestions.(10pts)Whattypeofinhibitoristhiscompound(beasspecificasyoucan)?Showthediagramoftheinhibitor’smechanism(byEdenotingenzyme,Sdenotingsubstrate,Idenotinginhibitor;forexample:E+S ESE+P).CalculatetheKm,KcatintheabsenceofinhibitorandKmapp,Kappinthepresenceofinhibitor(appdenotingapparent.Thetotalconcentrationofenzymeis2nM).Calculatetheinhibitorconstant Lysozymedestroysthecellwallofbacteriabycatalyzingthehydrolysisof1,4-β-linkagesbetweenN-acetylmuramicacid(NAM)andN-acetyl-D-glucosamine(NAG)residuesinapeptidoglycan(figureA).FigureBshowsthebindingofthepeptidoglycantotheactivesiteoflysozyme,adeepcleftacrosspartoftheglobularproteinsurface.Sixhexosesofthesubstratefitintothiscleft.FigureCshowsthehydrolyticprocessFigureFigureFigureFigureWhatcanyoutalkaboutthefigureBinaccordwiththeenzymaticWhatcanyoutalkaboutthefigureCinaccordwiththeenzymaticCalculatetheratiooftheenzymemoleculeswhichreallyworkatpH3.8,5.2,6.6toallenzymemolecules,andexinfigureDaccordingtoyourcalculation(pH=pKaFigureFigure+lg([A-]/[HA])；pKaGlu=5.9,pKaAsp=FigureFigure（注意：请将第V,VI两题答案写在单独的答题纸上，否者，自负前面已经给出，可以采用“参见……”的方式，以节省答题时间）（10分