学科分类
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40 个结果
  • 简介:蛋白质领域被保存,在相互作用起一个重要作用在之中的机能上地独立的结构联系了蛋白质。域域相互作用最近被用来预言蛋白质蛋白质相互作用(PPI)。一般来说,一双领域的相互作用概率用训练得分功能被获得。令人满意阀值,当“交往”,带那些领域的蛋白质对被考虑。在这研究,蛋白质的签名内容被利用在Saccharomycescerevisiae,Caenorhabditiselegin,和人预言PPI对现代人。蛋白质签名模式的类似被获得,PPI预言基于二进制类似得分函数被拉。结果证明由建议途径的预言的真积极的率用最大的可能性评价方法比那高是约32%,导致在与一个测试集合相比操作的接收装置下面的区域的22%增加什么时候特征(巨鸟)曲线。当包含一个或二签名的蛋白质被移开时,预言的PPI对的敏感显著地增加了。预言的PPI对是平均,11更多半预定在0.95的信心水平比随机的选择交往,并且平均,4比那些由也预言更好预定种系发生的介绍或基因表达介绍。

  • 标签: 组蛋白质 蛋白质标号 ROC曲线 交互作用
  • 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: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:Protein-proteininteractions(PPIs)havebeenwidelystudiedtounderstandthebiologicalprocessesormolecularfunctionsassociatedwithdifferentdiseasesystemslikecancer.Whilefocusedstudiesonindividualcancershavegeneratedvaluableinformation,globalandcomparativeanalysisofdatasetsfromdifferentcancertypeshasnotbeendone.Inthiswork,wecarriedoutbioinformaticanalysisofPPIscorrespondingtodifferentiallyexpressedgenesfrommicroarraysofvarioustumortissues(belongingtobladder,colon,kidneyandthyroidcancers)andcomparedtheirassociatedbiologicalprocessesandmolecularfunctions(basedonGeneOntologyterms).Weidentifiedasetofprocessesorfunctionsthatarecommontoallthesecancers,aswellasthosethatarespecifictoonlyoneorpartialcancertypes.Similarly,proteininteractionnetworksinnucleicacidmetabolismwerecomparedtoidentifythecommon/specificclustersofproteinsacrossdifferentcancertypes.Ourresultsprovideabasisforfurtherexperimentalinvestigationstostudyproteininteractionnetworksassociatedwithcancer.Themethodologydevelopedinthisworkcanalsobeappliedtostudysimilardiseasesystems.

  • 标签: 蛋白质相互作用 相关基因 癌症 差异表达基因 价格指数 生物过程
  • 简介:植物蛋白质蛋白质相互作用网络没被大规模实验识别了。以便更好在米饭理解蛋白质相互作用,预言的米饭Interactome网络(PRIN;http://bis.zju.edu.cn/prin/)介绍76,585个预言的相互作用包含5,049米饭蛋白质。在印射米饭的genomic特征以后(去注解,subcellular本地化预言,和基因表示),我们发现一个注解得好、生物学上重要的网络是足够富有的在高顺序的生物系统以内捕获许多重要功能的连接,例如小径和生物进程。而且,我们作为例子拿了疯盒子的包含域的蛋白质和生理节奏的节奏发信号小径证明功能的蛋白质建筑群和生物小径能有效地在我们的预言的网络被扩展。在PRIN的扩展分子的网络更加改进了这些分析的能力集成存在知识并且提供新奇卓见进基因和基因网络的功能和协作。

  • 标签: 蛋白质相互作用网络 大米蛋白 水稻 预测 基因组功能 生物学意义
  • 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:WedescribetheGALT-Protdatabaseanditsrelatedweb-basedapplicationthathavebeendevelopedtocollectinformationaboutthestructuralandfunctionaleffectsofmutationsonthehumanenzymegalactose-1-phosphateuridyltransferase(GALT)involvedinthegeneticdiseasenamedgalactosemiatypeI.Besidesalistofmissensemutationsatgeneandproteinsequencelevels,GALT-ProtreportstheanalysisresultsofmutantGALTstructures.Inadditiontothestructuralinformationaboutthewild-typeenzyme,thedatabasealsoincludesstructuresofover100singlepointmutantssimulatedbymeansofacomputationalprocedure,andtheanalysistoeachmutantwasmadewithseveralbioinformaticsprogramsinordertoinvestigatetheeffectofthemutations.Theweb-basedinterfaceallowsqueryingofthedatabase,andseverallinksarealsoprovidedinordertoguaranteeahighintegrationwithotherresourcesalreadypresentontheweb.Moreover,thearchitectureofthedatabaseandthewebapplicationisflexibleandcanbeeasilyadaptedtostoredatarelatedtootherproteinswithpointmutations.GALT-Protisfreelyavailableathttp://bioinformatica.isa.cnr.it/GALT/.

  • 标签: 蛋白质数据库 生物信息资源 突变体 半乳糖 结构 WEB应用程序
  • 简介:Inthepost-genomicera,variouscomputationalmethodsthatpredictprotein-proteininteractionsatthegenomelevelareavailable;however,eachmethodhasitsownadvantagesanddisadvantages,resultinginfalsepredictions.Herewedevel-opedauniqueintegratedapproachtoidentifyinteractingpartner(s)ofSemaphorin5A(SEMA5A),beginningwithsevenproteinssharingsimilarligandinteractingresiduesasputativebindingpartners.ThemethodsincludeDwyerandRoot-Bernstein/Dillontheoriesofproteinevolution,hydropathiccomplementarityofproteinstructure,patternofproteinfunctionsamongmolecules,informationondomain-domaininteractions,co-expressionofgenesandproteinevolution.AmongthesetofsevenproteinsselectedasputativeSEMA5Ainteractingpartners,wefoundthefunctionsofPlexinB3andNeuropilin-2tobeassociatedwithSEMA5A.WemodeledthesemaphorindomainstructureofPlexinB3andfoundthatitsharessimilaritywithSEMA5A.Moreover,avirtualexpressiondatabasesearchandRT-PCRanalysisshowedco-expressionofSEMA5AandPlexinB3andtheseproteinswerefoundtohaveco-evolved.Inaddition,weconfirmedtheinterac-tionofSEMA5AwithPlexinB3inco-immunoprecipitationstudies.Overall,thesestudiesdemonstratethatanintegratedmethodofpredictioncanbeusedatthegenomelevelfordiscoveringmanyunknownproteinbindingpartnerswithknownligandbindingdomains.

  • 标签: 蛋白质结构 相关蛋白 相互作用 APRIORI 互补 后基因组时代
  • 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: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: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:Identificationofproteinsbymassspectrometry(MS)isanessentialstepinpro-teomicstudiesandistypicallyaccomplishedbyeitherpeptidemassfingerprinting(PMF)oraminoacidsequencingofthepeptide.AlthoughsequenceinformationfromMS/MSanalysiscanbeusedtovalidatePMF-basedproteinidentification,itmaynotbepracticalwhenanalyzingalargenumberofproteinsandwhenhigh-throughputMS/MSinstrumentationisnotreadilyavailable.Atpresent,avastmajorityofproteomicstudiesemployPMF.However,therearehugedisparitiesincriteriausedtoidentifyproteinsusingPMF.Therefore,toreduceincorrectproteinidentificationusingPMF,andalsotoincreaseconfidenceinPMF-basedproteinidentificationwithoutaccompanyingMS/MSanalysis,definitiveguidingprinciplesareessential.Tothisend,weproposeavalue-basedscoringsystemthatprovidesguidanceonevaluatingwhenPMF-basedproteinidentificationcanbedeemedsufficientwithoutaccompanyingaminoacidsequencedatafromMS/MSanalysis.

  • 标签: 生物肽 PMF 蛋白质 识别能力
  • 简介:TheCoronaviridaefamilyischaracterizedbyanucleocapsidthatiscomposedofthegenomeRNAmoleculeincombinationwiththenucleoprotein(Nprotein)withinavirion.ThemoststrikingphysiochemicalfeatureoftheNproteinofSARS-CoVisthatitisatypicalbasicproteinwithahighpredictedpIandhighhydrophilicity,whichisconsistentwithitsfunctionofbindingtotheribophosphatebackboneoftheRNAmolecule.ThepredictedhighextentofphosphorylationoftheNproteinonmultiplecandidatephosphorylationsitesdemonstratesthatitwouldberelatedtoimportantfunctions,suchasRNA-bindingandlocalizationtothenucleolusofhostcells.SubsequentstudyshowsthatthereisanSR-richregionintheNproteinandthisregionmightbeinvolvedintheprotein-proteininteraction.TheabundantantigenicsitespredictedintheNprotein,aswellasexperimentalevidencewithsynthesizedpolypeptides,indicatethattheNproteinisoneofthemajorantigensoftheSARS-CoV.Comparedwithotherviralstructuralproteins,thelowvariationrateoftheNproteinwithregardstoitssizesuggestsitsimportancetothesurvivalofthevirus.

  • 标签: SARS 冠状病毒 N蛋白 结构分析 抗原性
  • 简介:唯一的肽(杯)的一个概念被建议并且实现了从双人脚踏车团spectrometry(MS/MS)识别整个房间的蛋白质离子系列。唯一的肽被定义为肽,不管它的长度,那仅仅在兴趣的proteome的一蛋白质存在,尽管这肽可以在一样的蛋白质非常出现一次。集成杯,一个二拍子的圆舞整个房间的蛋白质鉴定策略被开发进一步增加识别蛋白质的信心。包括吉祥物和SEQUEST包含Saccharomycescerevisiae和蛋白质鉴定工具的40,243个MS/MS离子系列的数据集被用来说明建议概念和策略。没有实现杯,SEQUEST识别的蛋白质是吉祥物识别的那些的2.26褶层。当杯被使用时,忍受唯一的肽的蛋白质由SEQUEST鉴别那些的3.89褶层被吉祥物识别。由跨comparing识别蛋白质的二个集合,仅仅从杯导出的89普通蛋白质被发现。在识别蛋白质之间的关键差异从每个蛋白质鉴定工具采用的filterng标准被结果。根据杯和蛋白质鉴定工具认出的蛋白质的公共分类的肽的起源,所有识别蛋白质是跨compared,导致拥有分配信心的不同层次的四组蛋白质。

  • 标签: 全细胞蛋白 蛋白鉴定 类肽 蛋白质识别 蛋白质组 蛋白质鉴定
  • 简介:WestudiedstructuralandimmunologicalpropertiesoftheSARS-CoVM(mem-brane)protein,basedoncomparativeanalysesofsequencefeatures,phylogeneticinvestigation,andexperimentalresults.TheMproteinispredictedtocontainatriple-spanningtransmembrane(TM)region,asingleN-glycosylationsitenearitsN-terminusthatisintheexteriorofthevirion,andalongC-terminalregionintheinterior.TheMproteinharborsahighersubstitutionrate(0.6%correlatedtoitssize)amongviralopenreadingframes(ORFs)frompublisheddata.ThefoursubstitutionsdetectedintheMprotein,whichcausenon-synonymouschanges,canbeclassifiedintothreetypes.OneofthemresultsinchangesofpI(isoelectricpoint)andcharge,affectingantigenicity.ThesecondchangeshydrophobicityoftheTMregion,andthethirdonerelatestohydrophilicityoftheinteriorstructure.PhylogenetictreebuildingbasedonthevariationsoftheMproteinappearstosupportthenon-humanoriginofSARS-CoV.Toinvestigateitsimmunogenicity,wesynthesizedeightoligopeptidescovering69.2%oftheentireORFandscreenedthembyusingELISA(enzyme-linkedimmunosorbentassay)withserafromSARSpatients.Theresultsconfirmedourpredictionsonantigenicsites.

  • 标签: M蛋白 SARS 冠状病毒 结构 免疫学特征
  • 简介:Inthefaceoftheworldwidethreatofsevereacuterespiratorysyndrome(SARS)tohumanlife,someofthemosturgentchallengesaretodevelopfastandaccurateanalyticalmethodsforearlydiagnosisofthisdiseaseaswellastocreateasafeanti-viralvaccineforprevention.Totheseends,weinvestigatedtheantigenicityofthespikeprotein(Sprotein),amajorstructuralproteinintheSARS-coronavirus(SARS-CoV).BaseduponthetheoreticalanalysisforhydrophobicityoftheSprotein,18peptidesweresynthesized.UsingEnzyme-LinkedImmunosorbentAssay(ELISA),thesepeptideswerescreenedintheserafromSARSpatients.Accordingtotheseresults,twofragmentsoftheSgenewereamplifiedbyPCRandclonedintopET-32a.BothSfragmentswereexpressedintheBL-21strainandfurtherpurifiedwithanaffinitychromatography.TheserecombinantSfragmentswereconfirmedtohavepositivecross-reactionswithSARSsera,eitherbyWesternblotorbyELISA.OurresultsdemonstratedthatthepotentialepitoperegionswerelocatedatCodons469-882intheSprotein,andoneepitopesitewaslocatedatCodons599-620.IdentificationofantigenicregionsintheSARS-CoVSproteinmaybeimportantforthefunctionalstudiesofthisvirusorthedevelopmentofclinicaldiagnosis.

  • 标签: SARS 冠状病毒 锚定蛋白 抗原区域
  • 简介:Abranchandboundalgorithmisproposedforthetwo-dimensionalproteinfoldingproblemintheHPlatticemodel.Inthisalgorithm,thebenefitofeachpossiblelocationofhydrophobicmonomersisevaluatedandonlypromisingnodesarekeptforfurtherbranchingateachlevel.Theproposedalgorithmiscomparedwithotherwell-knownmethodsfor10benchmarksequenceswithlengthsrangingfrom20to100monomers.Theresultsindicatethatourmethodisaveryefficientandpromisingtoolfortheproteinfoldingproblem.

  • 标签: 蛋白质 基因表达 狂犬病 疾病预防
  • 简介:增加的证据证明丝氨酸,threonine和酷氨酸残余上的蛋白质phosphorylation是在细菌的主要规章的translational以后修正。这评论在细菌的致病力集中于细菌的phosphoproteome的含意并且在phosphoproteomics和phosphorylation网络的连接加亮方法的最近的开发。在高精确性团spectrometry的最近的技术开发戏剧性地转变了proteomics并且使它可能一些彻底的地点特定的细菌的phosphoproteomes的描述。在一些细菌的phosphoproteomes的高许多酷氨酸phosphorylations在致病力建议他们的角色,特别在病原体主人相互作用的情况中;在细菌的邻蛋白质的高许多multi-phosphorylation地点是相对小的phosphorylation尺寸和蛋白质功能的精细的规定的指示物的赔偿。

  • 标签: 蛋白磷酸化 磷细菌 致病性 酪氨酸磷酸化 翻译后修饰 蛋白质组学