【摘要】 生物被膜(Biofilm)是条件致病菌表皮葡萄球菌(Staphylococcusepidermidis)的主要致病因素,生物被膜的形成依赖多糖PIA合成,合成PIA的糖基转移酶由icaADBC基因编码。以生物被膜形成能力不同的菌株为对象,通过研究不同环境对生物被膜形成、细菌总糖量及相关基因表达的变化,探索外界环境对生物被膜形成的影响及葡萄糖对生物被膜诱导的分子机制。有利于生物被膜形成培养条件促进生物被膜形成及多糖的表达,葡萄糖能诱导ica基因的表达和生物被膜形成,ica基因的反义寡核苷酸(ODN)能对抗葡萄糖的作用;葡萄糖作用下不同生长周期生物被膜形成相关基因ica、icaR、AtlE表达不同。表皮葡萄球菌生物被膜的形成与细菌糖代谢有关,葡萄糖通过上调ica表达诱导生物膜形成,但不需要ica基因的持续表达;葡萄糖的诱导作用不是直接通过调节AtlE和icaR基因来实现的更多还原

【Abstract】 The infection of \%S. epidermidis,\% an opportunistic human pathogen, depends on biofilm formation, and biofilm formation is closely related to environment. Researches in the thesis focused on two strains of \%S. epidermidis\% with different capability of biofilm formation. To find the mechanism of response to environment on biofilm formation, biofilm formation and expression of \%ica, icaR, AtlE\% in theses \%S. epidermidis\% cultivated in different grow environment and in media with glucose for different time were assayed. Glucose can induce the biofilm formation by inducing \%ica\% gene, but the inducing do not need continued \%ica\% expression, and other genes also contribute to the regulation; anti-ODN specially binding \%icaADBC\% can withstand biofilm inducing from glucose. These results suggest that biofilm formation closely related to growth environment, which is a complex regulation mechanism. Biofilm formation is closely related to bacteria energy metabolism and cell wall synthesis. Some crucial factors in the complex and integrated regulation system have not been known yet.更多还原