高渗透压法制备细菌外膜扫描电镜样品  

Preparation of samples for electron microscopy by high osmotic pressure method

作　　者：牛小羽[1] 牛畅[2,3] 冯尔玲[3] 刘先凯[3] 朱力[3] 张玫[1] 

机构地区：[1]首都医科大学附属宣武医院消化科,北京市100053 [2]首都师范大学生命科学学院,北京市100037 [3]军事医学科学院生物工程研究所病原微生物生物安全国家重点实验室,北京市100071

出　　处：《世界华人消化杂志》2013年第35期3994-3998,共5页World Chinese Journal of Digestology

基　　金：国家自然科学基金资助项目;No.81171531;国家"973"基金资助项目;No.2011CB504901~~

摘　　要：目的:近年来,电子显微技术在生物学领域得到了广泛的应用.本文利用生物电镜技术对福氏志贺氏菌外膜结构进行了研究,并对比不同制样方法对电镜照片的影响.方法:将各志贺氏菌分别在30℃和37℃的环境中培养,PCR检测毒力大质粒是否在传代中丢失.培养至稳定期后,收集菌液,分别用非高渗和高渗固定液固定,制备切片,使用电子显微镜观察细菌外膜结构.结果:在高渗透压环境下制样能使细胞质发生皱缩,有利于对细胞表面超微结构的观察.通过电镜图片对比,发现在37℃时,三株福氏志贺氏菌外膜脂多糖丰度均少于30℃.结论:高渗透压方法比普通制样方法更有利于对细菌表面超微结构进行观察.通过对电镜照片的观察,可以认为福氏志贺氏菌在不同培养温度下脂多糖的相对密度有所差异.AIM： To compare different methods for prepara-tion of samples for electron microscopic obser- vation of Shigellaflexneri surface structures. METHODS： Three Shigella flexneri strains were cultured and used to prepare samples for elec-tron microscopy. Samples were prepared in different osmotic environments. The obtained electron micrographs were compared to obtain the optimal sample preparation conditions.RESULTS： Hyperosmotic environment in sam-ple preparation often makes cytoplasmic shrink-age occur, which is beneficial for cell surface ultrastructure observation. By comparing the electron microscopic pictures of the three strains of Shigella flexneri, we found that the abundance of bacterial lipopolysaccharides （LPS） was less at 37 ℃ than that at 30 ℃. CONCLUSION： High osmotic pressure sample preparation is better than common methods in observing bacterial cell surface ultrastructures. Using this sample preparation method, electron microscopy analysis revealed that the relative density of LPS of Shigella flexneri varied among different culture temperatures.

关 键 词：生物电镜 福氏志贺氏菌 脂多糖 

分 类 号：R446.5[医药卫生—诊断学]