The cell envelope structure and properties of Mycobacterium smegmatis mc2155:: is there a clue for the unique transformability of the strain?
The cell envelope structure and properties of Mycobacterium smegmatis mc2155:: is there a clue for the unique transformability of the strain?
复制标题
DOI：
10.1099/mic.0.27869-0
复制
发表时间：
2005-06-01
期刊：
影响因子：
2.8
通讯作者：
Daffé, M
中科院分区：
文献类型：
--
作者：
Etienne, G;Laval, F;Daffé, M
耻垢分枝杆菌经常被用作致病性分枝杆菌的替代宿主，特别是自从从等基因粗糙野生型菌株ATCC 607中分离出可转化光滑形态型菌株mc（2）155以来。细胞被膜成分的生化分析显示，mc（2）155菌株缺乏极性糖脂，即脂寡糖和糖肽脂的极性亚家族。此外，后一种菌株与其亲本的不同之处在于细胞被膜的最外层和更深层之间的各种糖脂和磷脂的分布。在复合培养基中生长的mc（2）155细胞表面存在丝状和绳状结构，进一步支持了突变体细胞被膜超微结构的变化。重要的是，与野生型细胞相比，观察到突变体对疏水性鹅去氧胆酸盐的显著更快的摄取。综上所述，这些数据表明，表面暴露和包膜成分的性质是至关重要的表面特性，细胞壁渗透性和细菌表型，并建议mc（2）155菌株的可转化特性可能部分地解释了其细胞包膜的这些深刻的修改。
Mycobacterium smegmatis is often used as a surrogate host for pathogenic mycobacteria, especially since the isolation of the transformable smooth morphotype strain mc(2)155 from the isogenic rough wild-type strain ATCC 607. Biochemical analysis of the cell envelope components revealed a lack of polar glycolipids, namely the lipooligosaccharides and the polar subfamilies of glycopeptidolipids, in the mc(2)155 strain. In addition, the latter strain differs from its parent by the distribution of various species of glycolipids and phospholipids between the outermost and deeper layers of the cell envelope. The presence of filamentous and rope-like structures at the cell surface Of mc(2)155 cells grown in complex media further supported an ultrastructural change in the cell envelope of the mutant. Importantly, a significantly more rapid uptake of the hydrophobic chenodeoxycholate was observed for the mutant compared to wild-type cells. Taken together, these data indicate that the nature of the surface-exposed and envelope constituents is crucial for the surface properties, cell wall permeability and bacterial phenotype, and suggest that the transformable character of the mc(2)155 strain may be in part explained by these profound modifications of its cell envelope.