耐药表皮葡萄球菌生物被膜形成前、后差异蛋白表达的分析

Analysis of differential protein expression before and after biofilm formation of drug resistance Staphylococcus epidermidis

目的探讨耐药表皮葡萄球菌生物被膜形成前、后差异蛋白的表达。方法将耐药表皮葡萄球菌分为药物处理组(用400μg/mL鞣酸处理)和对照组(用生理盐水处理),观察菌落生长情况,并采用快速银染法鉴定药物作用前、后生物被膜的形成;用CRA平板法检测药物作用前、后,表皮葡萄球菌产生细胞间多糖黏附因子(PIA)的能力。用双向电泳技术对细菌总蛋白进行分离,并对差异蛋白点进行高效液相色谱-芯片/质谱(HPLC-Chip/MS)鉴定。结果与对照组比较,药物处理组表皮葡萄球菌菌落数明显减少(P<0.01),PIA生成能力减弱,生物被膜的形成被抑制。通过电泳分离,共得到19个差异表达的蛋白分子,其中13个仅在药物处理组表达升高,有6个仅在对照组表达升高。结论生物被膜形成是表皮葡萄球菌耐药的主要途径,差异蛋白在生物被膜的形成中可能起到关键作用。

Objective To explore the differential protein expression before and after biofilm formation of drug resistance Staph- ylococcus epidermidis.Methods Drug resistance Staphylococcus epidermidis were divided into drug treatment group（treated with 400μg/mL tannic acid）and control group（treated with saline）.The colony growth was observed and biofilm formation was identi- fied by rapid silver staining before and after drug treatment.CRA plate assay was adopted to detect the capability of Staphylococcus epidermidis for polysaccharide intercellular adhesion（PIA）production before and after drug treatment.Two-dimensional electro- phoresis technique was employed to separate total bacterial proteins and high performance liquid chromatography-Chip/mass spec- trometry（HPLC-Chip/MS）was used to identify the differential protein spots.Results Compared with control group,colony num- ber of Staphylococcus epidermidis（P〈0.01）,capability of PIA production and biofilm formation were reduced markedly.19 differ- entially expressed proteins were obtained by use of electrophoresis separation.Among them,13 proteins were found up-expressed only in drug treatment group and 6 up-expressed only in control group.Conclusion Biofilm formation is the principal pathway of drug resistance of Staphylococcus epidermidis and the differential proteins may play a key role in biofilm formation.