学科分类
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14 个结果
  • 简介:AstatisticalthermodynamictheoryoflinearproteinsolutionswasproposedwiththeaidofalatticemodelandappliedtotypeⅠantifreezeprotein(AFPI)solutions.ThenumericalresultsforseveralAFPIsolutionsshowthattheGibbsfunctionofthesolutionhasaminimumatacertainproteinconcentration,buttheproteinchemicalpotentialincreaseswithincreasingtheconcentration.TheinfluencesoftemperatureandproteinchainlengthontheAFPIchemicalpotentialwerealsodiscussed.Theevaluationforthecolligativedepressionofthefreezingpointconfirmsthattheantifreezeactionshouldberecognizedasnon-colligative.Thetheoreticaldeductionfortheconcentrationdependenceofthethermalhysteresisactivitycoincidesqualitativelywiththepreviousexperimentalandtheoreticalresults.

  • 标签: 蛋白质溶液 应用程序 抗冻蛋白 热力学性质 线性 蛋白质浓度
  • 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:Thispresentstudyinvestigatedtheabilityofvarioussoyproteinhydrolysates(SPHs)inbindingcalcium.ItwasdemonstratedthattheamountofCa-bounddependedgreatlyontheSPHsobtainedusingdifferentproteases,whichincluded:neutrase,flavourzyme,proteaseMandpepsin.ThemaximumlevelofCa-bound(66.9mg/g)occurredwhenproteaseMwasusedtohydrolyzesoyprotein.PeptidefragmentsexhibitinghighCa-bindingcapacityhadmolecularweightsofeither14.4or8-9kDa.ThelevelofCa-boundincreasedlinearlywiththeincrementofcarboxylcontentinSPHs,andfurtherdeamidationonSPHsfromproteaseMimprovedCa-bindingofthehydrolysate.

  • 标签: SOYBEAN protein HYDROLYSATES PROTEASE CALCIUM BINDING
  • 简介:Theinteractionofbromothymolblue(BB)withhumanserumalbumin(HSA)wasstudiedbyelectrochemicaltechniquesandasensitivemethodforproteinsassaywasdeveloped.WhenBBinteractedwithHSA,thevoltammetricpeakcurrentvalueofBBdecreasedlinearlywiththeconcentrationofHSAinarangeof1.0―40.0mg/L,andthepeakpotentialshiftednegatively.Basedontheresults,asensitiveassaymethodforproteins,suchasHSA,bovineserumalbumin(BSA),andeggalbuminetc.wasestablished.ThismethodwasfurtherappliedtodeterminingtheHSAinhealthyhumanbloodsamples,andtheresultsarenotsignificantlydifferentfromthoseobtainedbytheclassicCoomassieBrilliantBlueG-250spectrophotometicmethod.Thedetectingconditionsofthismethodwereoptimizedandtheinteractionmechanismwasdiscussed.Theresultsshowthattheelectrochemicalparameters(formalpotentialE0,standardrateconstantoftheelectrodereactionks,parameterofkineticnα)ofBBhavenoobviouschangesbeforeandaftertheinteraction,whichindicatethatBBcaninteractwithHSA,forminganelectrochemicalnon-activecomplex.Theequilibriumconstant(βs)andthebindingratio(m)forthiscomplexwerecalculated.Themis4andβsis1.41×1019.Thismethodisfast,simple,highlysensitive,andhasgoodselectivity,whichcanbeusedinclinicalmeasurements.

  • 标签: 人类血清蛋白 免疫血清样本 伏安法 蛋白质 电气化学
  • 简介:Sumoylationisanimportantproteinmodificationdiscoveredrecently.SUMO(smallubiquitin-relatedmodifier)pathwayregulatestheproteinstabilityandtranscriptionalactivitywitha12-kDasmallmolecularprotein,SUMO,ligatedtothetargetprotein.ThepurificationofSUMOproteinsisakeysteptorevealtheirfunction.ThepurposeofthisstudywastoconstructtherecombinantSUMO1geneclonedtoapGEX-4T-1vectortoexpressandpurifytheSUMO1-GSTfusionproteininEscherichiacoli.First,thefulllengthDNAsequenceofSUMO1genewasamplifiedbyPCRandwasligatedtopMD18-Tvector.ThentheSUMO1genewassubclonedtopGEX-4T-1prokaryoticexpressionvectorbetweenBamHIandXhoIsites,andtransformedinEscherichiacoliDH5αcells.Therightcolonieswereidentifiedbyrestrictiveenzymedigestionandsequencing.ThecorrectrebombinantplasmidofpGEX-4T-1-SUMO1wastransformedinEscherichiacoliBL21cellsandtheninducedbyIPTG(isopropyl-β-D-1-thiogalacto-pyranoside)toexpresstheSUMO1-GSTfusionprotein.ThehighlypurifiedSUMO1-GST(glutathioneS-transferase)fusionproteinwasobtainedbyaffinitychromatography.Finally,thepropertiesofSUMO1-GSTfusionproteinwereconfirmedbyCoomassiebrilliantbluestrainandWesternblotanalysis.TherecombinantplasmidofpGEX-4T-1-SUMO1wassuccessfullyconstructed,andSUMO1-GSTfusionproteinsweresuccessfullyexpressed.

  • 标签: GST融合蛋白 蛋白纯化 蛋白质修饰 SUMO 小分子蛋白质 基因克隆
  • 简介:Preparationandcharacterizationofthehapten-proteinconjugatesarefundamentaltodevelopingenvironmentalimmunoassays.Asahapten,1-pyrenebutyricacid(PBA)wasconjugatedtothecarrierproteinofbovineserumalbumin(BSA)orovalbumin(OVA)byactiveestermethod.Infraredspectra(IR)showedthatPBA-BSAandPBA-OVAconjugatesweresuccessfullyprepared.Thenumberofthehaptensconjugatedtothecarrierproteinwasdeterminedbyultravioletspectra(UV)andmatrix-assistedlaserdesorptionionizationtime-of-flightmassspectrometry(MALDI-TOF-MS).ThecalculatedaveragebindingratiosofPBA/BSAandPBA/OVAwere18:1and10:1byUV,and31:1and22:1byMALDI-TOF-MS,respectively.Althoughtherewasadiscrepancybetweentheresultsdeterminedbythetwomethods,bothofthemwereusefulforthecharacterizationofthehapten-proteinconjugates.TheantibodywasproducedagainsttheantigenofPBA-BSA,andtheaffinitywastestedbythedoubleagardiffusionmethod.Theconjugatesandtheantibodycouldbeusedfordevelopingasensitiveandselectiveimmunoassayofpolycyclicaromatichydrocarbons(PAHs).

  • 标签: 多轮芬芳烃 半抗原 结合物 免疫测定
  • 简介:新奇tetra-carboxylphenyl杯的相互作用[4]有牛的心细胞色素c(Cc)的arene(TCPC)被荧光光谱学和分子的建模方法首先调查。稳定的1:1建筑群的形成被荧光滴定监视,并且它的有约束力的常数是1.916脳107L摩尔?1。分子的建模揭示TCPC的识别机制到Cc表面,也就是说,静电的相互作用驾驶TCPC到Cc表面,并且货车derWaals相互作用面向TCPC平行到Cc劈开。

  • 标签: 蛋白质表面识别 荧光光谱学 分子模型 细胞色素
  • 简介:Fromthepress-residueofthefreshroottuberofTrichosantheskirilowiiMaxim(Cu-curbitaceae),anewribosome-inactivatingprotein(RIP),trichobitacin,wasisolated.IthastheactivityofRNAN-glycosidaseandcaninhibitthegrowthofhumanplacentaltrophoblasticcells.Itsmolecularweightis27,228Da(ES-MS)andpI9.6.ItisasinglechainbasicRIP.Itsaminoacidcompositionwasdetermined.ItisanewRIP.Itconsistsof0.7~0.9%galactoseandmaybeaglycoprotein.ItsA’-andC-terminalaminoacidisAspandAla,respectively.ItsN-terminalpreliminaryaminoacidsequencehasbeendetermined.

  • 标签: Trichobitacin ribosome-inactivating PROTEIN trichosantbin PROTEIN ISOLATION
  • 简介:在这个工作,静止阶段与phosphorylcholine(PC)修改了的两性离子的离子层析(ZIC)的一种准备方法被hydrolyzing在结合的phosphorylcholine二氯化物以后获得到diol硅石更好在酸的蛋白质和基本蛋白质的同时的分离作为ZIC静止阶段ligand探索PC组的特征。结果证明同时,二种酸的蛋白质和三种基本蛋白质能完全被分开母鸡鸡蛋白色被分开并且净化并且三种鸡蛋白人部件ovalbumin,G2ovoglobulin和ovotransfemin蛋白质被一个单身者完全分开PC-ZIC上的步列,所有蛋白质的纯净上面到达了95%。PC-ZIC静止阶段成功地比以前在这份报纸报导与更好的分离能力和选择被改进。

  • 标签: 色谱固定相 快速分离 两性离子 卵清蛋白 鸡蛋白 胆碱
  • 简介:一综合(dimethylsiloxane)(PDMS)poly,有二的微芯片削尖为方便样品注射,跑的缓冲区更新和清洗的隧道拉长建议被介绍了。没有交换供应和注射十字隧道的复杂电源,样品直接通过拉长的入口尖端被介绍进分离隧道。运用缓冲区更新或隧道清洗的操作被vacuuming简化尖端的结束并且把另外的尖端放进答案小瓶。因此,没有软平版印刷术和血浆结合设备,这个制造方法罐头容易经济地被用于很分析的实验室。新奇PDMS微芯片的吸引人的表演被为蛋白质的分离使用导致激光的荧光察觉表明了。在0.04mol/L磷酸盐缓冲区的0.04%Brij35的增加(pH7.0)能在multienzyme药片减少蛋白质的粘附并且更容易做分离。electroosmotic流动(文件结束)在动态修改microchannel在311的范围展出pH独立。

  • 标签: 微芯片 集成电路 制作成本
  • 简介:Thecompleteaminoacidsequenceofβ-momorcharin,aribosome-inactivatingproteinfromtheseedsofMomordicacharantiaLinn(Cucurbitaceae)hasbeendetermined.Thishasbeendonebythesequenceanalysisofpeptidesobtainedbyenzymaticdigestionwithtrypsin,chymotrypsinandS.aureusV8protease,aswellasbychemicalcleavagewithBNPS-skatole.Theproteinconsistsof249aminoacidresiduescontainingoneasparagine-linkedsugargroupattachedtothesiteofAsn51andhasacalculatedrelativemolecularmassof28,452Dawithoutadditionofthecarbohydrate.Comparisonofthissequencewiththoseoftrichosanthinandotherribosome-inactivatingproteinsfromdifferentspeciesofplantsshowsasignificanthomologywitheachother.Regardingthesimilarityoftheirbiologicalproperties,anactivedomainoftheseproteinshasbeenpredictedhere.

  • 标签: Momorcharin ribosome-inactivating protein (RIP) PRIMARY structure
  • 简介:Thelackofefficientandnon-toxicgenedelivery,preferablywithnon-viralDNAvectors,isgenerallyregardedasamajorlimitationforgenetherapy.Inthisstudy,awheathistoneH4genewasclonedfromTriticumaestivum,sequenced,modifiedandexpressedinE.coli.ThewheathistoneH4geneandreconstructedH4TLgeneencodedwheathistoneH4andarecombinantproteinof141aminoacidswithanapproximatemolecularweightof15500.GelelectrophoresismobilityshiftassaysdemonstratedthatthepurifiedproteinhadhighaffinityforDNA.Mostsignificantly,thecomplexofplasmidpEGFP/C1withH4TLwastransfectedwithincreasedefficiencyintoMCF-7,HO8910,LNCap,A549andHeLacellsinvitro.Theseresultsdemonstratethatthetargetingofnon-viralvectorstotumor-specificreceptorsprovidesacheap,simpleandhighlyefficienttoolforgenedelivery.

  • 标签: 非病毒基因载体 小麦基因 重组蛋白 融合蛋白 转染 病毒DNA
  • 简介:Thepurposeofthisstudyistoexploretheexpressionofgrowth-associatedprotein(GAP-43)inspinalcordsegmentsconnectedwithinjuredsciaticnervebythetreatmentwithbrazileininmice.Unilateralsciaticnerveinterruptionandanastomosiswereperformed.Physiologicalsaline(blankgroup),highdose,middledoseandlowdoseofbrazileinwereadministratedintragastricallytohealthyadultBALB/cmiceinseparategroups.L4―6spinalsegmentsconnectedwiththesciaticnervewereharvested.Real-timePCR(Polymerasechainreaction)andWesternblotanalysiswereperformedtodetecttheexpressionofGAP-43inspinalsegments.Histologicalstainingonmyelinandtheelectrophysiologywereperformedtoexaminethesciaticnerverecovery.GAP-43wasactivatedinspinalcordL4―6connectedwithinjuredsciaticnerve.Inthesurvivaltimeof12h,24h,3d,5d,7dand14d,GAP-43expressioninthemotorneuronsofspinalcordofthehighdosegroupandthatinthemiddledosegroupweresignificantlyhigherthanthoseonthelowdoseandblankgroups.MyelininthehighdosegroupandthatinthemiddledosegroupweremorematureandthepotentialamplitudeandMNCV(motornerveconductionvelocity)inthehighandmiddledosegroupswereobviouslyhigherthanthoseinthelowdosegroupandblankgroup.BrazileinfacilitatestheexpressionofGAP-43inneuronsinspinalcordL4―6segmentsconnectedwithinjuredsciaticnerve,whichpromotesnerveregeneration.

  • 标签: 脊髓神经元 生长相关蛋白 坐骨神经 受伤 小鼠 激活