抗菌肽基因的改造及其植物表達(dá)載體的構(gòu)建.pdf

1、西南農(nóng)業(yè)大學(xué)碩士學(xué)位論文抗菌肽基因的改造及其植物表達(dá)載體的構(gòu)建姓名：牛國清申請(qǐng)學(xué)位級(jí)別：碩士專業(yè)：生物化學(xué)及分子生物學(xué)指導(dǎo)教師：裴炎2002.5.1ModificationofantimicrobialpeptidegenesandtheconstructionofplantexpressionvectorsharboringthesesgenesCandidate：NiuGuoqingAdvisor：ProPeiyan(Biotech

2、nologyResearchCenter，SouthwestAgriculturalUniversityChongqing，400716，China)AbstractCationicantibacterialpeptidesarefoundininsect，animalandplantTheyaregroupedintofourclassesincludingcecropins，magainins，meliainsanddefensin

3、sCEMAconsistsofeightaminoacidfromNterminusofcecropinAandCterminusofmodifiedmelittinItmaintainspotentantibacterialactivityanddeprivesofthehemolyticactivityWithitsbroad—spectmmandnonspecificpotentantibacterialactivity，cati

4、onicantibacterialpeptidehasthepotentialtobewidelyusedinplantdiseaseresistancegeneticengineeringHoweverCEMAwasrefrainedinplantgeneticengineeringapplicationduetoitstoxictoplantcellsThemodificationofCEMAwillfacilitateitswid

5、eapplicationInthispapersignalpeptidewasaddedbeforetheN—terminusofCEMAwiththeintentionteduceitstoxictoplantcellswhilemaintainingthestrongantibacterialactivityPlantdefensinsarecystein—richantibacterialpeptidesPlantdefensin

6、disruptsthecellmembraneofphytopathogendifferentlyfromCEMAthatcontactsdirectlywiththecellmembranePlantdefensinsarethoughttOinteractwithspecificreceptorharboringinthecellmembraneTheyinhibitsthegrowthoffungi(filamentousfung

7、iespecially)whilearenon一’toxictoplantcellsThemainresultswereasfollows：1ObtainingofSPCEMA(signalpeptidemodifiedCEMA)SPCEMA(187bp)wasamplifiedwithtwolongcomplementaryprimers(P2andP3)andtwoprimers(P1andP4)containingrestrict

8、ionenzymerecognitionsitePlantexpressionvectorpESPCEMAwasconstructedaftersubcloninginpUCl21andothervectors2ObtainingofMCEMA(modifiedCEMA)andplantdefensinAFPgeneMCEMA(141bp)wasamplifiedwithpUCSPCEMAplasmidastemplateandP5，P