共生乳酸菌酵母菌的篩選及產(chǎn)信號(hào)分子AI-2的研究.pdf

1、分類(lèi)號(hào)TS252.1學(xué)校代碼10129UDC663.1學(xué)號(hào)2012209022具有共生關(guān)系的酵母菌乳酸菌的篩選及對(duì)產(chǎn)信號(hào)分子AI2的影響ThePreliminaryStudyonInfluenceofYeastontheProductionofAI2Signal共生共生乳酸菌酵母菌的篩選及產(chǎn)信號(hào)分子AI2的研究StudyonSymbioticScreeningSignalingMolecularAI2betweenLacticAcidB

2、acteriaYeasts申請(qǐng)人：郭倩茹學(xué)科門(mén)類(lèi)：工學(xué)學(xué)科專(zhuān)業(yè)：農(nóng)產(chǎn)品加工及貯藏工程研究方向：食品生物技術(shù)指導(dǎo)教師：賀銀鳳教授論文提交日期：二〇一五年六月StudyonSymbioticScreeningSignalingMolecularAI2betweenLacticAcidBacteriaYeastsAbstractTherearemanyreasonsmechanismsinsymbioticmicrooganisms.Most

3、researchersstudythesymbiosisontrophicinteractionscooperativemetabolismtheybarelyfromtheaspectofquumsensing(QS)toinvestigate.InthisexperimentQSwasexaminedtolaythefoundationfthefurtherstudyofsymbioticmechanisms.Ninelactica

4、cidbacteria(LAB)strainseightyeaststrainsisolatedfromkoumisswerescreenedtwicetothesymbioticstrains.Metaboliteswereaddedtotheculturemediumswiththeadditionofthesameamountofsalineascontrolgroups.Turbidityvaluesdryweightvalue

5、sweremeasuredinthestationaryphase.BettersymbioticcombinationsinthefirstsceeningwerechosentorescreenwithintheviablecountasanindicatthendetectedinfluenceonproducingsignalingmoleculeAI2bysymbioticstrains.Influencesonproduci

6、ngsignalingmoleculeAI2bymonoxeniemonoxeniewithmetabilitescocultivatonweredetectedwithinVibrioharveyiBB170asanindicat.TheresultsshowedthatthereweretwelvecombinationsthatLABmetabolitesbenefitedtheyeasts.Therewerethirtyfour

7、yeastsmetabolitesbenefitedthegrowthofLABduringseventytwopotentialsymbioticcombinations.Whilesevencombinationsshowedmutualpositiveinteractions.ThreepairsofsymbioticstrainswereedintherescreeningwhichwereLAB4YST2LAB7YST2LAB

8、9YST2.Theywerepickedouttodofurtherresearches.AllofLAB4LAB7LAB9couldproducesignalingmoleculeAI2LAB4LAB7couldproduceme.Meoverrelativefluescenceintensitypositivelycrelatedwithcelldesityinintialgrowth.Thestrainspeakedtherela

9、tivefluescenceintensityatstationaryphase(18h).YST2didn’tproducesignalingmoleculeAI2.WhilethemetabolitesofYST2couldpromoteLAB’sproducingsignalingmoleculeAI2especiallyLAB4LAB7(P0.01).Thereasonmaybewastheyeaststimulatedtheg

10、rowthofLAB.CoculturedYST2LAB4YST2LAB9significantlypromotingLAB’sproducingsignalingmoleculeAI2(P0.01).WhilecoculturedYST2LAB7hadbothpromotionssuppressionsthereasonneedtobefurtherstudied.KeyWds:SymbiosisLABYeastsScreeningQ