大肠杆菌细菌菌蜕的制备及初步研究  

Construction and characterization of E.coli bacterial ghosts

作　　者：蔡昆[1] 包士中[1] 史晶[1] 刘昊[1] 高翔[1] 王慧[1] 

机构地区：[1]军事医学科学院微生物流行病研究所病原微生物生物安全国家重点实验室,北京100071

出　　处：《军事医学科学院院刊》2008年第5期436-438,共3页Bulletin of the Academy of Military Medical Sciences

摘　　要：目的:利用温度控制噬菌体PhiX174裂解基因E的表达,制备大肠杆菌细菌菌蜕,鉴定其裂解效率并观察其形态。方法:利用PCR技术扩增分离了噬菌体PhiX174裂解基因E并构建其表达质粒,并将质粒转化大肠杆菌DH5α构建工程菌。工程菌培养温度从28℃突升至42℃,每15 min检测菌液D600值,诱导后4 h收集菌体。体外菌落计数计算裂解效率,并通过电镜观察菌蜕结构。结果:获得273 bp的PhiX174裂解基因E全长基因及表达质粒。菌液D600在温度突升至42℃后30 min开始持续下降,2 h后基本维持不变。4 h后收集菌体测得裂解效率为99.99%。电镜观察菌蜕为具有完整外膜结构的细菌空壳,并且无细胞毒性。结论:本研究成功利用噬菌体PhiX174裂解基因E实现了大肠杆菌细菌菌蜕的制备,为进一步的疫苗及递送系统研究奠定了基础。Objective：To prepare E. coli bacterial ghosts generated by the controlled expression of the PhiX174 lysis gene E and analyze its lysis rate and configuration. Methods： The full-length gene of PhiX174 lysis gene E was obtained and the recombinant expression plasmid was constructed. E. coli DH5α containing expression plasmid were induced to produce lysis by immediately shifting the temperature of culture from 28℃ to 42℃. The D600 of culture was monitored every 15 min during the induction. After 4 hours, the bacteria were collected to calculate the lysis rate by colony forming unit （CFU）count. Then, the configuration of bacterial ghosts was observed. Results： The 273 bp full-length E gene and expression plasmid were obtained. D600 of culture began to decline 30 min after the temperature rose to 42℃ and the lysis was completed after 2 h. The lysis rate of culture collected 4 h later was 99.99%. TEM observation proved that bacterial ghosts were empty bacterial cell envelopes, which had the whole surface composition and had no cytotoxicity. Conclusion： The E. coli bacterial ghosts which were prepared and identified by using of PhiX174 lysis gene E might facilitate future development of bacterial ghost vaccine and delivery systems.

关 键 词：大肠杆菌 细菌菌蜕 噬菌体PhiX174裂解基因E 温度控制 

分 类 号：R392[医药卫生—免疫学]