胞外DNA是耻垢分枝杆菌生物被膜的主要成分  

Extracellular DNA is the main component of the biofilm Mycobacterium smegmatis

作　　者：张巧丽[1] 李树林[1] 安雅男 王超[1] 李燕[1] 于录[1] Zhang Qiao-li Li Shu-lin An Ya-nan Wang Chao Li Yan Yu Lu(Key Laboratory of Zoonosis, Ministry of Education/Institution of Zoonosis, Jilin University, ChangChun 130062)

机构地区：[1]吉林大学人兽共患病研究所教育部重点实验室,长春130062

出　　处：《中国抗生素杂志》2016年第11期874-877,共4页Chinese Journal of Antibiotics

基　　金：国家"十二五"重大传染病专项课题(No.2012ZX10003002-001);吉林省科技发展计划项目(No.20150101108JC)

摘　　要：目的本实验以无致病性的耻垢分枝杆菌Mc^2 155为结核分枝杆菌模型菌进行生物被膜成分研究。方法利用24孔细胞培养板建立体外耻垢分枝杆菌生物被膜培养模型；借助DNaseⅠ作为eDNA抑制剂分析其在生物被膜的存在情况，通过结晶紫染色对生物被膜进行定量；早期加入外源基因组DNA对生物被膜的影响进行评估；利用荧光显微镜考察SYTOX orange标记生物被膜的主要成分胞外DNA（eDNA）。结果体外培养的耻垢分枝杆菌Mc^2 155能形成典型生物被膜；早期加入DNaseⅠ明显抑制了生物被膜的产量；早期加入基因组DNA有利于提高生物被膜产量。特异染料SYTOX orange能对耻垢分枝杆菌生物被膜染色，说明eDNA是耻垢生物被膜的主要成分。结论本研究首次证明eDNA是耻垢生物被膜的主要成分，这为治疗分枝杆菌感染和耐药控制提供了新的思路。Objective To study the ingredients of the biofilm, the non-pathogenic strain Mc^2 155 of Mycobacterium smegmatis was used as the model of M. tuberculosis. Methods 24-well cell culture plates are used to establish the model of Mycobacterium smegmatis biofilm in vitro. DNase I was used as eDNA inhibitors to analyze eDNA presence in the biofilm. Biofilm was quantified by crystal violet staining. Exogenous genomic DNA was added to assess its impact on biofilm at early stages. Fluorescence microscope was used to study the extracellular DNA as the main component of the biofilm with SYTOX orange marking. Results Mc^2 155 strain was capable of forming typical biofilm. DNase Ⅰ could significantly inhibit biofilm production in initial formation processes of biofilm. Genomic DNA was beneficial to improve biofilm production. SYTOX orange as DNA-specific dye was used to stain M. smegmatis biofilm, indicating eDNA is the main component of biofilm. Conclusion This is the first proof that DNA is the main component of biofilm of M. smegmatis, which provides a new way for the treatment of mycobacterial infection and resistance controlling.

关 键 词：分枝杆菌 生物被膜 胞外DNA 

分 类 号：R378.911[医药卫生—病原生物学]