The Relationship Of Penicillin Binding Protein-1b And Alginate Generated In Pseudomonas Aeruginosa

【Objective】Via restraining PBP-1b encoded gene mrcB expression by RNAinterference (RNA interference, RNAi) in pseudomonas aeruginosa toexplore the relationship between PBP-1b and alginate encoded gene algD，in order to find a new idea about clinical biofilm.【Methods】Through the method of siRNA expression vector，design2shRNAsequences according to targeted mrcB gene，construct pMF54mrcB shRNAinterference vectors； by electricity transformation get pMF54mrcBshRNA1/pMF54mrcB shRNA2/pMF54into the pseudomonas aeruginosa, RT-PCRscreening high restrain efficiency of interference vector, and calculateinhibition rate at the24hours、 the third day and the sixth dayrespectively. At the same time use the RT-PCR to detect alginate encodedgene algD in PAO1standard strain and transformation strain respectivelyin the three time points，through the statistics treatment to observeif there is difference between them in algD expression.【Results】 The constructed pMF54mrcB shRNA1/pMF54mrcB shRNA2interference vectors are confirmed right by DNA sequencing.Get pMF54mrcBshRNA1/pMF54mrcB shRNA2/pMF54into the pseudomonas aeruginosa byelectricity transformation to contrast with the blank group respectively.RT-PCR detect the24hours mrcB expression， pMF54mrcB shRNA2havestatistically significant difference. The inhibition rate of the24hours、the third day and the six days are26%、41%、9%respectively.The algD gene expression in standard PAO1strain is statisticallysignificant differences by Oneway ANOVA in three time points and on thethird day the highest. The algD expression in transformated strain areall high in this three time points. Compared algD gene expression levelbetween standard strain and transformed strain in three time points byT test，there ise not statistically significant in third days P>0.05.【Conclusion】Alginate encoded gene algD in PAO1standard strain expressi highest amount in the third day；The algD expression in transformatedstrain are obvious higher in this three time points，the rise ahead oftime and maintain a long time；PBP-1b lacking increase the amount of algDexpression, and in the third day expression is not significant maybeassociated with the PAO1algD express maximum in third days；The specificregulation mechanism of the relationship of PBP-1b and the alginate isunknown，needs to be further study.