双语分子生物学ppt

中北大学化工与环境学院生物工程专业MolecularBiology(分子生物学)主讲:张志军博士、博导、副教授埃博拉病毒截至2014年8月26日，埃博拉已在塞拉利昂、利比亚和几内亚造成1427人死亡。2014年8月9日，中国宣布已掌握埃博拉病毒抗体基因，同时具备对埃博拉病毒进行及时检测的诊断试剂研发能力，这让世界为之惊喜。主要参考教材•PCTurneretal.InstantNotesinMolecularBiology(Secondedition).BIOSScientificPublishersLimited,2000•分子生物学(第三版)导读版(精要速览系列)•朱玉贤，李毅，郑晓峰编著。现代分子生物学（第3版）高等教育出版社2007-11-1•RobertF.WeaverMolecularbiology2004.（Thirdedition）分子生物学学习方法及注意问题专心听讲做好笔记认真思考学会归纳注意纪律预习复习章节名称理论（学时）实验（学时）1Cellsandmacromolecules22NucleicacidandChromosome43DNAreplication64DNAdamage,repairandrecombination65Transcription146Proteinsynthesis87Viruses28Tumorandoncogenes29Technologyofmolecularbiology416合计4816课程主要内容1.1Cellularclassification1.2Subcellularorganelles1.3Macromolecules1.4Largemacromolecularassemblies1.Cellsandmacromolecules1.1Cellularclassification•Prokaryotes：–Eubacteria(真细菌)–Acchaea(古细菌)•Eukaryotes：–Plants–Animals–Fungi–Protist(原生生物)ProkaryotesandeukaryotesSchematicofaeukaryoticcellSchematicofaprokaryoticcellDifferentiation(分化)1.2Subcellularorganelles(亚细胞器)•Nucleinucleoli（核仁）,nucleus•MitochondriaandChloroplasts•Endoplasmicreticulum•Microbodies•OrganelleisolationNucleiEndoplasmicreticulumandribosomesMitochondriaandChloroplastsMicrobodies:lysosome1.3Macromolecules•Proteins•Nucleicacids•Polysaccharides•Lipids•Complexmacromolecules•Proteins–polymersofaminoacids,peptidebonds•Nucleicacids–DNAandRNA,polymersofnucleotides,–mRNA,tRNA,rRNA•Polysaccharides–Polymersofsimplesugars,glycosidebonds–Theyfunctionsmainlyasnutritionalsugarstoresandasstructuralmaterial.–Cellulose,starch,chitin,mucopolysaccharides(黏多糖)•Lipids–Keycomponentsofmembranes,protectivecoatsandotherstructures.–Glycerides(甘油酯),phospholipids(磷脂)，sphingolipids（鞘脂，如神经氨酰）•Complexmacromolecules–Nucleoproteins(核蛋白),ribozyme（核糖体）–Glycoproteins–Proteoglycans(mucoproteins)蛋白多糖（粘蛋白）–Lipid-linkedproteins–glycolipids1.4Largemacromolecularassemblies•Proteincomplexes–Cytoskeleton:microtubules,microfilaments,intermediatefilaments–Theseorganizetheshapeandmovementofcellsandsubcellularorganelles.–Ciliaandflagella(纤毛和鞭毛)arealsocomposedofmicrotubulescomplexedwithdyneinandnexin（动力蛋白和连接蛋白）.•Nucleoproteins–Bacterial70Sribosomes:50Slargersubunit(23Sand5SRNA+31proteins)+30Ssmallsubunit(16SRNA+21proteins)–Eukayotic80Sribosomes:60Slargersubunit(28S,5.8Sand5SRNAs+31proteins)+40Ssmallsubunits(18SRNA)–ChromotincontainsDNAandthebasichistoneproteins.•Membranes–Membranephospholipidsandsphingolipids(鞘脂)formbilayers.–Membraneproteinsmaybeperipheral(外周的)orintegral（整合的）andactasreceptors,enzymes,transportersormediatorsofcellularinteraction.•Noncovalentinteraction(非共价互作)–Charge-charge(电荷)interactions–Charge-dipole(偶极)anddipole-dipoleinteraction–Hydrogenbonds氢键–Hydrophobicinteraction疏水相互作用思考题1.试述原核和真核细胞的异同点。2.亚细胞器主要有哪些？各自主要结构和功能是什么？3.生物大分子包括哪些？分别叙述其组成结构。4.试举出三种大分子的组装形式。2NucleicacidandChromosomeIncluding2.1Propertiesofnucleicacid2.2ProkaryoticandEukaryoticchromosomestructure2.1Propertiesofnucleicacid2.1.1Nucleicacidstructure2.1.2Chemical&physicalproperties2.1.3Spectroscopic(光谱学)&thermal（热力学）properties2.1.4DNAsupercoiling2.1.1NucleicacidstructureBasesNucleosides(核苷)base+sugarNucleotides(核苷酸)base+sugar+phosphatePhosphodiesterbondsBasesDNA:adenine(A),guanine(G),cytosine(C),thymine(T)RNA:adenine(A),guanine(G),cytosine(C),uracil(U)DNA/RNAsequenceConventionally,DNAorRNAarerepresentedbytheirsingleletterA,T,G,CorU.Writethesequenceswith5'-endattheleft.DNA:5'-ATAAGCTC-3'orATAAGCTCRNA:5'-AUAGCUUGA-3'direction:ATAAGisnotthesameasGAATADNAdoublehelixBasepairingComplementarybasepairsAntiparallelminorgroove;majorgrooveright-handed(clockwise)B-formOverwound;underwound·TheB-formofDNAisadoublehelixconsistingoftwopolynucleotidechainsthatrunantiparallel.·ThenitrogenousbasesofeachchainareflatpurineorpyrimidineringsthatfaceinwardsandpairwithoneanotherbyhydrogenbondingtoformA-TorG-Cpairsonly.·Thediameterofthedoublehelixis20Å,andthereisacompleteturnevery34Å,with10basepairsperturn.·Thedoublehelixformsamajor(wide)grooveandaminor(narrow)groove.KeyConceptsA,BandZhelices•Z－DNA：它是左手双螺旋，与右手螺旋的不同是螺距延长(4.5nm左右)，直径变窄(1.8nm)，每个螺旋含12个碱基对，分子长链中磷原子不是平滑延伸而是锯齿形排列，有如“之”字形一样，因此叫它Z构象，这一构象中的重复单位是二核苷酸而不是单核苷酸；而且Z－DNA只有一个螺旋沟，它相当于B构象中的小沟，它狭而深，大沟则不复存在。•进一步的分析还证明，Z－DNA的形成是DNA单链上出现嘌呤与嘧啶交替排列所成的。比如CGCGCGCG或者CACACACA。不同右手双螺旋DNA的结构参数•双螺旋碱基倾碱基夹碱基间距螺距每轮碱小沟宽／nm×大沟宽nmו角／（°）角（°）/nm／nm基数小沟宽nm大沟宽nm•B-DNA036.00.3373.4100.57×0.751.17×0.85•C-DNA638.00.3313.19.30.48×0.791.05×0.75•D-DNA45.00.3030.13×0.670.89×0.58•A-DAN2032.70.2562.8111.10×0.280.27×1.35•总之，DNA的双螺旋结构永远处于动态平衡中，DNA分子构象的变化与糖基和碱基之间空间相对位置有关。2.1.2Chemical&physicalpropertiesofnucleicacidStabilityofnucleicacidsHydrogenbondingHydrophobicinteractionsanddipole-dipoleinteractionsEffectofacidStrongacid---hydrolyzedcompletely,HClO4,100℃Moderateacid---themosteasilyhydrolyzedbondsareselectivelybroken,hydrolysisofthepurinebaseglycosylicbonds---apurinic(脱嘌呤).Morecomplexchemistryhasbeendevelopedwhichremovesbasesspecially,andcleavestheDNAorRNAatparticularbases.EffectofalkaliTochangethetautomeric(互变异构的)stateofthebases.Chemicaldenaturationurea(尿素)andformamide（