28237.sigma因子sigk在天藍(lán)色鏈霉菌細(xì)胞分化過程中的功能機(jī)制研究

1、浙江大學(xué)生命科學(xué)學(xué)院碩士學(xué)位論文Sigma因子SigK在天藍(lán)色鏈霉菌細(xì)胞分化過程中的功能機(jī)制研究姓名：侯曉平申請(qǐng)學(xué)位級(jí)別：碩士專業(yè)：生物化學(xué)與分子生物學(xué)指導(dǎo)教師：李永泉毛旭明20091216浙江大學(xué)碩士學(xué)位論文’—————_—__——_—————————●_————_————————_———————●——————一AbstractStreptomycescoeBcolorisakindofsoildwellingbacteriawith

2、acomplexlifecycleandabundantsecon血rymetabolicproducts，whichischallengedwithdiverseenvironmentalstressesinitssoil“／conditionTandduringitsdevelopmentalprocessItdevelopesasetofregulatorysystemofmorphologydifferentiationandm

3、etabolismduringmillionsofyearsevolutionofactorisakindofregulatorthatinitialstranscriptionofgenes，whichcallbederidedintooToand054s仃曲】rallv0rdifferentfamilysfuctionallyMostofthegroup3familysigmafactorsof070familyreposedunt

4、ilnowarepositiveregulatorinmorphologicaldevelopmentofStreptomycescoelicolorInthisstudywereportedthatdeletionofSigK(SC06520)，asigmafactorinStreptomycescoeBcolo，，causedallearlierswitchfromvegetativemyceliatoaerialmyceliaan

5、dhigherexpressionofchpEandchpHthanthatinthewildtypeLossofSigKalsoresukedinacceleratedandenhancedproductionofantibioticsactinorhodinandundecylprodigiosinandincreasedexpressionofactlIorf4andredDTheseresultssuggestedthatSig

6、KhadanegativeroleinmorphologicaltransitionandsecondarymetabolismMeanwhile，twopotentiallynonspecificcleavagesoccurredbetweenSigKandgreenfluorescentproteinandtheSigKfusionproteinsexpressedundertheconstitutivepromoterermEp毒

7、sharplydecreasedanddisappearedwhenaerialmyceliaemergedThesedatasuggestedthatthepromptdegradationofSigKduringvegetativehyphadevelopmentaccountedforthepropertimingofmorphogenesisandthatSigKvanishedtemovetheblockfort11eemer

8、genceofaerialmyceliaThus，weproposedthatSigKhadinhibitoryrolesondevelopmentaleventsandthattheseinhibitoryeffectsmaybereleasedbySigKdegradationKeywords：Streptomycescoelico]orSigK，negativeregulatoryfactor，differentiation，de