ica操纵子对表皮葡萄球菌在不同骨科植入物表面黏附和生物膜形成的影响

摘要

Objective To investigate the effect of ica operon on adherence and biofilm formation of Staphylococcus epidermidis(S.epidermidis)at orthopedic implants,and to provide theoretical basis for the use of clinical orthopedic materials.Methods The icaADBC genes of S.epidermidis were amplified by PCR.The expression of ica genes was detected by fluorescence quantitative PCR.The contents of polysaccharide intercellular adhesion (PIA) were determined by phenol-sulfuric acid method.The ability of bacterial adherence was detected by colony counting method and the ability of biofilm formation was measured by crystal violet staining method.Results The icaADBC genes were presented and expressed in eleven S.epidermidis strains.The strains with high icaABDC gene expression had higher PIA product.S.epidermidis isolates had the strongest adherence and biofilm formation ability on bone material,followed by titanium and stainless steel.The expression of icaA gene correlated with the biofilm formation of bacteria on three biomaterials.Conclusion S.epidermidis isolates had the different adherence and biofilm formation on different biomaterial implants.Ica gene regulates the biofilm formation of S.epidermidis by regulating the expression of PIA.%目的 探讨ica操纵子对表皮葡萄球菌在骨科植入物表面黏附和生物膜形成能力的影响,为临床骨科材料的使用提供理论依据.方法 采用PCR扩增表皮葡萄球菌ica操纵子的icaADBC基因,荧光定量PCR检测ica操纵子基因的表达,苯酚-硫酸法检测细胞间多糖黏附素(PIA)的合成,黏附能力检测采用菌落平板计数法,生物膜形成能力检测采用结晶紫染色法.结果 11株表皮葡萄球菌临床菌株扩增出ica操纵子的icaADBC基因,且在菌株中均有表达.ica操纵子基因表达高的菌株其PIA分泌量较高.表皮葡萄球菌在骨组织上的黏附和生物膜形成能力最强,其次为钛合金和不锈钢.icaA基因表达与细菌在3种生物材料上的生物膜形成相关.结论 表皮葡萄球菌在不同骨科植入物上具有不同的黏附和生物膜形成能力,ica操纵子基因通过调节PIA分泌量而影响表皮葡萄球菌生物膜的形成.