Research The Function Of Gene ComE,comX,cinA,dnaK In Competence Of Streptococcus Pneumoniae

Objective: Use RT-PCR to monitor expression of three gene involved in competence of S.pn and a virulence gene dnaK(maybe a gene involved in competence too).Afteramplification . We analysis the function of gene(comE,comX,cinA) in induction of competence, discuss the feasibility to use comE defective S.pn as competence S.pn, and research the function of gene dnaK.Method: S.pn was grown in CTM to a certain OD(550nm) ,extraction RNA of S.pn per 30 minutes , then, after reverse transcription ,use PCR to amplifiction gene comE,comX,cinA and dnaK. Monitor their expression in wild S.pn and comE defective S.pn. Result: 1. In wild S.pn ,comE,comX and cinA's expression have similarity in different time: in early time ,they did not express(or show very lowexpression level),and then, at a same time, their expression level increased very highly .But in comE defective S.pn, comX and cinA did not express at all.2. dnaK was express in every time ,not only in wild S.pn, but also in comE defective s.pn。dnaK's expression was not same as comE,comX and cinA.3. In vitro ,we induced the competence of wild S.pn: in CTM, comE,comX and cinA(gene involved in competence of S.pn) increase very highly at a certain time.Conclusion: In CTM, the gene involved in competence increased very highly after some minutes, In comE defective S.pn, the gene comX and cinA did not express, it tell me comE maybe a important gene ,it can control other gene's expression. So, we can use comE defective S.pn as competence defective S.pn to research pathogenicity of S.pn. In wild and comE defective S.pn, dnaK show similar expression, and it was different from comE,comX and cinA. We consider dnaK was not a gene involved in competence.