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1、摘要金黃色葡萄球菌趨化抑制蛋白(chemotaxjs1nhibitoryProtejnof&印垣Pf?!辌c砒口駢塒,cHIPs)是由金黃色葡萄球菌分泌到菌體外的一種蛋白,能特異性地與中性粒細(xì)胞和單核細(xì)胞上的c5a受體(c5aR)和fMLP受體(FPR)結(jié)合,從而阻止細(xì)胞的趨化作用。但是,可否將CHlPs作為藥物來(lái)治療由c5a或日訂LP誘發(fā)的炎癥性疾病或?qū)HIPs作為免疫原來(lái)防制金黃色葡萄球菌感染,目前尚不清楚。本試驗(yàn)設(shè)計(jì)合成了一對(duì)PCR擴(kuò)增特異性引物,分別從金黃色葡萄球Newman株和cowallI株中擴(kuò)增獲得了cHIPs基因,進(jìn)一步將其克隆到pMDl8-T載體獲得
2、重組質(zhì)粒pMD-N和pMD-c。并對(duì)其進(jìn)行測(cè)序分析。結(jié)果,與GenB“k中提供的cHlPs基因序列相比,Newman株具有100%的同源性,cowan】株只有一個(gè)堿基突變R298A—G:二者氨基酸同源性均為100%。說(shuō)明cHIPs基因高度保守。將pMD-N,pMD-c質(zhì)粒和pEl’32a(+)表達(dá)載體進(jìn)行勘mH】和曲¨雙酶切,回收cHlPs基因片段,將其插入到pET32a(+)原核表達(dá)載體并轉(zhuǎn)化到B02l(DE3)EcDff,經(jīng)篩選分別獲得pET-N仍E3和pET-c艦3重組體細(xì)菌。經(jīng)1P1B誘導(dǎo)表達(dá)和sDs.PAGE分析,結(jié)果與對(duì)照菌株相比,誘導(dǎo)后的pE]:N仍E3和
3、pET-c/DE3表達(dá)約為31.8kDa的融合蛋白,且表達(dá)蛋白存在于菌體超聲波裂解上清中;進(jìn)一步對(duì)其進(jìn)行westem_blotting分析證實(shí),表達(dá)的融合蛋白為目的蛋白。說(shuō)明本試驗(yàn)cHIPs得到了良好表達(dá),且為可溶性蛋白。用MagneHisT”蛋白純化系統(tǒng)對(duì)表達(dá)的CHPs蛋白進(jìn)行純化,并將純化后的cHIPs蛋白用于人工刨傷感染韻動(dòng)物模型試驗(yàn),結(jié)果與對(duì)照組相比,使用cHDs蛋白組對(duì)創(chuàng)傷感染愈合具有明顯的延遲作用,表明cHIPs蛋白對(duì)炎癥具有抑制或延緩作用。關(guān)鍵訶:趨化抑制蛋白,基因克隆,原核表達(dá),c5a受體。fMLP受體Abstractchemotaxisinhjbito
4、ryprotejnof所珈,∞D(zhuǎn)cc淞口“M珊(cHIPs)isakindofproteinthatexcretedbyS口ⅣrP淞.CHlPscanspec雨callybindtoc5areceptor(C5aR)a11dtheforInylatedpeptidereceptor(FPR)existingonthesurfaceofneutrophils枷dmonoc”es,therebyb】ockchemotaxjsofneutrophjlsandmonocytesmediatedbyC5aandfonnylatedpeptides,respectiVely.But
5、,itis1essknownuptonowthatwhemerCHIPScallbeusedaSacandidatedmgfor廿10seinn啪matorydiseasesinducedbyC5aandforInylatedpeptidesaIld/0rana11tigenforpmV0kingimmuneresponseagainst&口we螂infectjon.1nthjs『epon,thegenesofcHIPs如m&dm℃淞Newmanandcow柚lstrainswere鋤plifiedbyPCRwithapairofprimerSandsuccessfIl
6、llyintroducedrespectjVelyjntopMDl8-Tvectors.1’worecombinalltclones,pMD-NandpMD-C,can了ingtlleCHIPSgeneofNe砌aIla11dCowallIstrainwereob詛inedandsequenced.ThenucleotidesequenceOf也eCHlPSgene‰NewmanstrainhadlOO%hom0109ytomesequencepublishedpreviouslyinGenB卸k鋤dthat療DmCowan1strainhadonlyonemu協(xié)tio
7、n(R299A_÷G)comparedw曲廿lesequencepublislledpreviouslyinGenBank.Thededuced啪inoacidsequencesofllleCHIPSf而mNewmaIla11dCowaIl1s打ajnwere100%homologytothesequencepublishedpreviously.ThoSesu鵲estedthatt11eCHIPSgenewashigh】yconserva石Ve.Thep∞_N,pMDcp1踟idandthepET32a(+)ex孵sionVec瞬weT