熒光假單胞菌2P24中phoQ基因的克隆及其對群體感應系統(tǒng)的調控.pdf

1、中國農業(yè)大學碩士學位論文熒光假單胞菌2P24中phoQ基因的克隆及其對群體感應系統(tǒng)的調控姓名：高偉申請學位級別：碩士專業(yè)：植物病理學指導教師：張力群20060601中國農業(yè)大學碩士學位論文AbstractAbstractBacterialstrainPseudomonaslluorescens2P24wasisolatedfromwheattakealldeclinesoilThisstraincouldproduceseveralan

2、tifungalcompounds，suchashydrogencyanide(HCN)，antibiotic2，4diacetylphloroglucinol(24DAPG)，siderophore(s)andextracellularproteinase，andshowedinhibitorytoRalstoniaSoIclnoceorlznl，Rhizoctoniasolaniandotherpathogens，andhi曲eff

3、iciencytocontrolsoilbornediseasessuchastomatebacterialwiltandwheattake—a11Strain2P24hasaclassicalquorumsensingsystemconsistedofpcolandpcoRgenes，whichisanimportantregulatorysystempeainenttoitsbiocontrolabitityThetranscrip

4、tionatreportersystemofsignalsynthesizedgenepcolwasconstructedbyfusionofapromoterlessedLacZgenewiththepcoIgoneTn5medimedchromosomalintegrationwasperformedandthemutantswiththedecreasedorincreasedexpressionofthepcolgenewere

5、selectedThirteensuchmutantswereobtainedfrom18000Tn5inseaedmutantsSequenceanalysisshowedthattheproteinencodedbyTn5insertedgeneofYB6andYBlOshareshighidentitytothegeneencodingsensorkinasePhoQinPfluorescensPf5f88％1andPaerugi

6、nosaPA01(68％)ThephoQinsertionmutantdidnotevidentlyaffecttheproductionofantifungalmetabolitesandthebiocontrolactivityofP∥uorescens2P24whichpcolgenewasdestroiedagainstwheattake—alldisease，butsignificantlyenhancedthetranscr

7、iptionofpc01Thecomplementedspaincontainingaplasmidbearing∞oQgonecouldrestorethetranscriptionofpcoItothelevelofthewildtypeTheresultsindicatethatphoQisanimportantregulatoryfactorlocatedattheupstreamoftheQSsysteminPseudomon