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116 个结果
  • 简介:TheE(envelope)proteinisthesmalleststructuralproteininallcoronavirusesandistheonlyviralstructuralproteininwhichnovariationhasbeendetected.WeconductedgenomesequencingandphylogeneticanalysesofSARS-CoV.Basedongenomesequencing,wepredictedtheEproteinisatransmembrane(TM)pro-teincharacterizedbyaTMregionwithstronghydrophobicityandα-helixcon-formation.Weidentifiedasegment(NH2-_L-Cys-A-Y-Cys-Cys-N_-COOH)inthecarboxyl-terminalregionoftheEproteinthatappearstoformthreedisulfidebondswithanothersegmentofcorrespondingcysteinesinthecarboxyl-terminusoftheS(spike)protein.ThesebondspointtoapossiblestructuralassociationbetweentheEandSproteins.OurphylogeneticanalysesoftheEproteinsequencesinallpub-lishedcoronavirusesplaceSARS-CoVinanindependentgroupinCoronaviridaeandsuggestanon-humananimalorigin.

  • 标签: SARS 冠状病毒 膜蛋白 E蛋白
  • 简介:Theadsorptionofproteinonnanoparticleswasstudiedbyusingdynamiclightscatteringtomeasurethehydrodynamicsizeofbothpureproteinandnanoparticlesadsorbedwithdifferentamountsofprotein.Thethicknessoftheadsorbedproteinlayerincreasesasproteinconcentration,butdecreasesastheinitialsizeofnanoparticles.Afterproperlyscalingthethicknesswiththeinitialdiameter,weareabletofitallexperimentaldatawithasinglemastercurve.Ourexperimentalresultssuggestthattheadsorbedproteinsformamonolayeronthenanoparticlesurfaceandtheadsorbedproteinmoleculesareattachedtotheparticlesurfaceatmanypointsthroughapossiblehydrogen-bonding.Ourresultsalsoindicatethatasproteinconcentrationincreases,theoverallshapeoftheadsorbedproteinmoleculecontinuouslychangesfromaflatlayerontheparticlesurfacetoastretchedcoilextendedintowater.Duringthechange,thehydrodynamicvolumeoftheadsorbedproteinincreaseslinearlywithproteinconcentration.

  • 标签: ADSORPTION Dynamic light scattering HYDRODYNAMIC RADIUS
  • 简介:管理生命的自然现象的内在的原则是在最近的年里收到到期的重要性的关键问题之一。没有规模的建筑学的特色是大多数连接节点(中心)的活力。这篇文章的主要目的是由在二个相互作用系统的拓扑的参数上考虑建筑上的模式和中心的移动的后果分析蛋白质蛋白质和果蝇melanogaster的新陈代谢的相互作用网络。分析证明两个相互作用网络跟随一个没有规模的模型,建立从改变的状况,很真实的世界网络遵循小世界模式的事实。平均路径长度出现了一双重并且三方面的增加(从9.42~20.93并且从5.29~17.75变化,分别地)分别地,由于中心的删除为蛋白质蛋白质和新陈代谢的相互作用联网。相反,节点的任意的消除没在蛋白质蛋白质和新陈代谢的相互作用网络的拓扑的参数显示出任何显著不同(平均路径长度:9.42+/-0.02和5.27+/-0.01,分别地)。为二个盒子的这越轨行为强调大多数连接节点的意义到网络的自然拓扑学。

  • 标签: 拓扑学 蛋白质 新陈代谢 果蝇
  • 简介:ProteinkinaseRAFisstrategicallylocatedinthe'Ras-MAP-kinasesignaltransductionpathway',aprinciplesystemwhichtransmitssignalsfromgrowthfactorreceptorstothenucleus,resultingincellproliferation.GrowthfactorresponsesaremediatedinpartbyactivationofRas,whichinturnactivatesRAFtophosphorylateMEK,itsdownstreamsubstrate.MEKactivatesMAPkinasetoinfluencenuclearevents.itisclear.however,thatanetworkofsignalsotherthanthosecarredbyRasplaysaroleinRAFregulation.Theseorthogonalinfluencesaremediatedbu:serine/threoninekinases,tyrosinekinases,andprotein-proteininteractions.AsafurthercomplicationtotheRAFnetwork,threeisoformsofRAFhavebeenestablishedwhichhavedivergentN-terminalregulatorydomains,Whereasthesedivergentregulatorydomainsimplicateisoform-specificfunctions,noclearevidenceorhypothesisfordistinctfunctionsforindividualisoformshasbeenpresented.Recently,'isoform-specificproteininteractions'havebeenidentifiedamongnumerousproteinsinteractingwithRAF,ThesestudiesmayservetodelineateindependentfunctionsforRAFisoforms.

  • 标签: RAF家族 转译后控制 蛋白质-蛋白质相互作用 细胞 信号传导 交叉口
  • 简介:Azurins,awildtypeandageneticallymutantK27alteredone,wereimmobilizedonannealedgoldsurfaceandinvestigatedbymeansofatomicforcemicroscopy.Itwasfoundthatthesurfacecoverageandheightdistributionoftheadsorbedproteinmoleculesaredifferentfromeachother,whichispossiblytheresultofthedifferentorientationonthesurface.Itisbelievedthatthewildtypeazurinisconnectedtogoldsurfacebythedisulphidebridge;whilethemutant,K27C,mightbethroughthethiolgroupsofthecysteineresiduesontheirsurface.

  • 标签: 原子力显微镜 蛋白质 形态学 硫醇 半胱氨酸 AZURIN
  • 简介:ThenameofSRproteinsisderivedfromtheirtypicalRSdomainthatisrichinserine(Ser,S)andarginine(Arg,R).Theyareconservedinevolution.Uptonow,10membersoftheSRproteinfamilyhavebeenidentifiedinhumans.SRproteinscontainoneortwoRNAbindingmotifsasidefromtheRSdomain,andalsopossessspecialbiochemicalandimmunologicalfeatures.AstothefunctionsofSRproteins,theyfacilitatetherecruitmentofthecomponentsofsplicesomeviaprotein-proteininteractiontoprompttheassemblyofearlysplicesome;whileinalternativesplicing,tissue-specificallyexpressedSRproteinalongwiththerelativeratioofSRproteinandheterogeneousnuclearribonucleoprotein(hnRNP)iscomposedoftwomainregulativemechanismsforalternativesplicing.Almostallofthebiochemicalfunctionsareregulatedbyreversiblephosphorylation.

  • 标签: SR蛋白质 丝氨酸 精氨酸 核蛋白 磷酸化 蛋白质交换通道
  • 简介:Proteinphosphorylationplaysanimportantroleinvariouscellularprocesses.Duetoitshighcomplexity,themechanismneedstobefurtherstudied.Inthelastfewyears,manymethodshavebeencontributedtothisfield,butalmostalloftheminvestigatedthemechanismbasedonproteinsequencesaroundproteinsites.Inthisstudy,weimplementanexplorationbycharacterizingthemicroenvironmentsurroundingphosphorylatedproteinsiteswithamodifiedshellmodel,andobtainsomesignificantpropertiesbytherank-sumtest,suchasthelackofsomeclassesofresidues,atoms,andsecondarystructures.Furthermore,wefindthatthedepletionofsomepropertiesaffectsproteinphosphorylationremarkably.Ourresultssuggestthatitisameaningfuldirectiontoexplorethemechanismofproteinphosphorylationfrommicroenvironmentandweexpectfurtherfindingsalongwiththeincreasingsizeofphosphorylationandproteinstructuredata.

  • 标签: 微环境 磷酸化作用 贝壳 蛋白质
  • 简介:Inathree-dimensionaloff-latticemodel,themethodofShakhnovichandGutinforminimizingtheHamiltonianisappliedtothedesignofaprotein-modelchain.Theeffectofthenumberofhydrophobicandhydrophilicmonomertypesonthedesignabilityofaprotein-modelchainisinvestigated.Thesimulationresultsrevealthatthenumberofhydrophobicmonomertypesisamuchmoreimportantfactorthanthatofthepolarmonomertypesinthedesignofaprotein-modelchain.

  • 标签: 分子生物学 蛋白质模型链 可设计性
  • 简介:Inthisarticle,asphericalchitosangelcrosslinkedbyepichlorohydrinwasprepared.Itwasthenloadedwithcopperionstoproduceametalchelateaffinityadsorbentforprotein.Theuptakeofbovineserumalbumin(BSA)bytheaffinityadsorbentwasinvestigated,andtheadsorptioncapacityforBSAashighas40mg/g-wetbeadswasobserved.TheadsorptionequilibriumdatawaswellcorrelatedbytheLangmuirequation.TheadsorptionwasconsiderablyaffectedbypH.Inaddition,theamountofBSAadsorbedontothebeadsdecreasedwiththeincreasingofaqueousphaseionicstrength,soadsorbedBSAcanbedesorbedbyadjustingpHorionicstrengthofthesolution.

  • 标签: 吸附剂 金属螯合物 蛋白 摄取
  • 简介:Thenucleocapsidprotein(Nprotein)hasbeenfoundtobeanantigenicproteininanumberofcoronaviruses.WhethertheNproteininsevereacuterespiratorysyndrome-associatedcoronavirus(SARS-CoV)isantigenicremainstobeelucidated.UsingWesternblotandEnzyme-linkedImmunosorbentAssay(ELISA),therecombinantNproteinsandthesynthesizedpeptidesderivedfromtheNproteinwerescreenedinserafromSARSpatients.AllpatientserainthisstudydisplayedstrongpositiveimmunoreactivitiesagainsttherecombinantNproteins,whereasnormalseragavenegativeimmunoresponsestotheseproteins,indicatingthattheNproteinofSARS-CoVisanantigenicprotein.Furthermore,theepitopesitesintheNproteinweredeterminedbycompetitionexperiments,inwhichtherecombinantproteinsorthesynthesizedpeptidescompetedagainsttheSARS-CoVproteinstobindtotheantibodiesraisedinSARSsera.OneepitopesitelocatedattheC-terminuswasconfirmedasthemostantigenicregioninthisprotein.AdetailedscreeningofpeptidewithELISAdemonstratedthattheaminosequencefromCodons371to407wastheepitopesiteattheC-terminusoftheNprotein.UnderstandingoftheepitopesitescouldbeverysignificantfordevelopinganeffectivediagnosticapproachtoSARS.

  • 标签: 抗原性 SARS 冠状病毒 核壳体蛋白
  • 简介:Functionalcharacterizationofeverysingleproteinisamajorchallengeofthepostgenomicera.Thelarge-scaleanalysisofacell'sproteins,proteomics,seekstoprovidetheseproteinswithreliableannotationsregardingtheirinteractionpartnersandfunctionsinthecellularmachinery.Animportantsteponthiswayistodeterminethesubcellularlocalizationofeachprotein.Eukaryoticcellsaredividedintosubcellularcompartments,ororganelles.Transportacrossthemembraneintotheorganellesisahighlyregulatedandcomplexcellularprocess.Predictingthesubcellularlocalizationbycomputationalmeanshasbeenanareaofvividactivityduringrecentyears.Thepubliclyavailablepredictionmethodsdiffermainlyinfouraspects:theunderlyingbiologicalmotivation,thecomputationalmethodused,localizationcoverage,andreliability,whichareofimportancetotheuser.Thisreviewprovidesashortdescriptionofthemaineventsintheproteinsortingprocessandanoverviewofthemostcommonlyusedmethodsinthisfield.

  • 标签: 蛋白质 细胞定位 预测方法 染色体组 蛋白质组
  • 简介:Anewmethodwasdescribedforusingarecurrentneuralnetworkwithbiasunitstopredictcontactmapsinproteins.Themaininputstotheneuralnetworkincluderesiduespairwise,residueclassificationaccordingtohydrophobicity,polar,acidic,basicandsecondarystructureinformationandresidueseparationbetweentworesidues.Inourwork,adatasetwasusedwhichwascomposedof53globulinproteinsofknown3Dstructure.Anaveragepredictiveaccuracyof0.29wasobtained.Ourresultsdemonstratetheviabilityoftheapproachforpredictingcontactmaps.

  • 标签: 循环神经网络 蛋白质 预测 血红素 三维结构
  • 简介:Theadenomatoidodontogenictumorischaracterizedbytheformationofduct-likestructuresandappearanceofeosinophilicmaterials.Eosinophilicmaterialsshowamorphousmassordropletsamongtheepithelialcells.Intheduct-likestructures,itshowsathinlayerofbasementmembranel...

  • 标签: Adenomatoid ODONTOGENIC TUMOR Amyloidprotein BASEMENT MEMBRANE
  • 简介:Objective:Toinvestigatetheroleandclinicalsignificanceofp16proteininCondylomaAcuminatum(CA)anditscancerization.Methods:Theexpressionofp16proteinwastestedin33CAsamplesand7cancerizedCAsamplesbyimmunohistochemicalassays.Results:Therewasabnormalexpressionofp16proteininCAandcancerizedCA,mainlymajorproteinexpression.Thep16proteinexpresseedindifferentlocationsindifferentcaseswasasfollows:Inbasallayercellsinnormalcuits;inspinouslayer,granularlayerandstratumcorneumlayercellsinCA;inkeratinpearlperipheralandspinouslayercellsincancerizedCA.Conclusion..Therewasmajorexpressionofp16proteininCAandcancerizedCA,andtheseproteinofthetwogroupsmightnotnaturallybethesame.Ourstudyindicatedthatinclinicalpractice,whenmajorp16proteinexpressioninCAoccurs,it'sriskofcancerizationshoudbesuspected.

  • 标签: P16蛋白 尖锐湿疣 癌化反应 基因表达
  • 简介:Usingatriangularlatticemodeltostudythedesignabilityofproteinfolding,weovercametheparityproblemofpreviouscubiclatticemodelandenumeratedallthesequencesandcompactstructuresonasimpletwo-dimensionaltriangularlatticemodelofsize4+5+6+5+4.Weusedtwotypesofaminoacids,hydrophobicandpolar,tomakeupthesequences,andachieved223+212differentsequencesexcludingthereversesymmetrysequences.Thetotalstringnumberofdistinctcompactstructureswas219,093,excludingreflectionsymmetryintheself-avoidingpathoflength24triangularlatticemodel.Basedonthismodel,weappliedafastsearchalgorithmbyconstructingaclustertree.Thealgorithmdecreasedthecomputationbycomputingtheobjectiveenergyofnon-leafnodes.Theparallelexperimentsprovedthatthefasttreesearchalgorithmyieldedanexponentialspeed-upinthemodelofsize4+5+6+5+4.Designabilityanalysiswasperformedtounderstandthesearchresult.

  • 标签: 蛋白质 折叠结构 三角形栅格模型 结构设计 快速搜索树
  • 简介:Thecorona-likespikesorpeplomersonthesurfaceofthevirionunderelectronicmicroscopearethemoststrikingfeaturesofcoronaviruses.TheS(spike)proteinisthelargeststructuralprotein,with1,255aminoacids,intheviralgenome.Itsstructurecanbedividedintothreeregions:alongN-terminalregionintheexte-rior,acharacteristictransmembrane(TM)region,andashortC-terminusintheinteriorofavirion.WedetectedfifteensubstitutionsofnucleotidesbycomparisonswiththeseventeenpublishedSARS-CoVgenomesequences,eight(53.3%)ofwhicharenon-synonymousmutationsleadingtoaminoacidalternationswithpredictedphysiochemicalchanges.ThepossibleantigenicdeterminantsoftheSproteinarepredicted,andtheresultisconfirmedbyELISA(enzyme-linkedimmunosorbentassay)withsynthesizedpeptides.AnotherprofoundfindingisthatthreedisulfidebondsaredefinedattheC-terminuswiththeN-terminusoftheE(envelope)pro-tein,basedonthetypicalsequenceandpositions,thusestablishingthestructuralconnectionwiththesetwoimportantstructuralproteins,ifconfirmed.Phyloge-neticanalysisrevealsseveralconservedregionsthatmightbepotentdrugtargets.

  • 标签: 抗原性 S蛋白 SARS 冠状病毒 蛋白结构
  • 简介:Humanpolymorphonuclearleukocytes(PMN)havebeenreportedtocompletelylackofDNA-dependentproteinkinase(DNA-PK)whichiscomposedofKuproteinandthecatalyticsubunitDNA-PKcs,neededfornonhomologousend-joining(NHEJ)ofDNAdouble-strandbreaks.PromyelocyticHL-60cellsexpressavariantformofKuresultinginenhancedradiationsensitivity.ThisraisesthequestioniflowefficiencyofNHEJ,instrumentalforthecellularrepairofoxidativedamage,isanormalcharacteristicofmyeloiddifferentiation.HereweconfirmedthecompletelackofDNAPKinPMNproteinextracts,andtheexpressionofthetruncatedKu86variantforminHL-60.However,thisdegradationofDNA-PKwasshowntobeduetoaDNA-PK-degradingproteaseinPMNandHL-60.Inaddition,byusingaprotease-resistantwholecellassay,bothKu86andDNA-PKcscouldbedemonstratedinPMN,suggestingthepreviouslyreportedabsenceinPMNofDNA-PKtobeanartefact.ThelevelsofKu86andDNA-PKcsweremuchreducedinPMN,ascomparedwiththatofthelymphocytes,whereasHL-60displayedamarkedlyelevatedDNA-PKconcentration.Inconclusion,ourfindingsprovideevidenceofreduced,notdepletedexpressionofDNA-PKduringthematurestagesofmyeloiddifferentiation.

  • 标签: 粒细胞 人类 蛋白激酶 基因修复 表达 非同源末端连接
  • 简介:DEVELOPMENTOFAVERSATILESENSINGMEMBRANEFORIMMUBILIZATIONOFPROTEINANDANEWIMMOBILIZATIONMETHODY.K.Zhou,J.W.Yuan,S.Q.Xu,B.H.Shu(D...

  • 标签: :immobilization or protein BIOTIN-AVIDIN system sensingmembrane
  • 简介:Objective:Toconstructarecombinantplasmidcontainingtheoutermembraneprotein2(Omp2)geneofChlamydiatrachomatisandexpressOmp2inE.coli.Methods:Theomp2geneofC.trachomatisserovarDwasclonedintopQE30vectorfollowingPCRamplificationfromgenomicDNA.E.coliM15transformantswereinducedtoexpressthefusionproteinbyIPTGandtheproductwasidentifiedbySDS-PAGEandWesternblot.Results:ConfirmedbyenzymecleavageanalysisandDNAsequencing,acorrectrecombinantplasmidpQE30/omp2wasconstructed.Thefusionproteinfromthetransformantswasapproximately60kDainsizeinSDS-PAGEanalysis,whichcouldspeciallyreactwithanti-6×HismousemonoclonalIgGantibodies.Conclusion:WesuccessfullyexpressedOmp2inE.coilM15,providinganefficientandsimplesystemforassayingtheimmunologicalpropertiesofOmp2.

  • 标签: 原核表达 外膜蛋白2 衣原体 沙眼 重组器官 质粒