Construction of a rhamnose mutation in Bacillus anthracis affects adherence to macrophages but not virulence in guinea pigs
Construction of a rhamnose mutation in Bacillus anthracis affects adherence to macrophages but not virulence in guinea pigs
复制标题
DOI：
10.1016/j.micpath.2004.10.001
复制
发表时间：
2005-01-01
影响因子：
3.8
通讯作者：
Friedlander, AM
中科院分区：
文献类型：
--
作者：
Bozue, JA;Parthasarathy, N;Friedlander, AM
全孢子提取物的碳水化合物分析证实了炭疽芽孢杆菌的完全毒性艾姆斯菌株的孢子中存在鼠李糖。在B内鉴定了含有与鼠李糖生物合成基因rmlACBD具有高度同源性的基因座的基因簇。炭疽菌染色体通过使用B的艾姆斯菌株内的基因的内部片段形成部分二倍体共整合体，使该簇的第一个基因rmlA失活。anthracis，构建突变株Ames-JAB 1。从这个突变体的孢子的碳水化合物分析表明，损失的鼠李糖。当测定巨噬细胞的孢子感染时，我们检测到与艾姆斯野生型菌株的回收率相比，Ames-JAB 1菌株的回收率显著降低。当用细胞松弛素-D预处理巨噬细胞时，突变体的孢子的恢复进一步受阻，表明孢子不能与巨噬细胞结合。然而，在豚鼠攻击实验中，在突变体和野生型病毒之间没有观察到毒力差异。这些结果表明，鼠李糖掺入到B的孢子外壳中。炭疽菌是与巨噬细胞最佳相互作用所必需的，但在该动物模型中不是完全毒力所必需的。(C)2004年由Elsevier Ltd.出版。
Carbohydrate analyses of whole-spore extracts have confirmed the presence of rhamnose in the spore of the fully virulent Ames strain of bacillus anthracis. A gene cluster containing loci with high homology to the rhamnose biosynthetic genes, rmlACBD, was identified within the B. anthracis chromosome. The first gene of this cluster, rmlA, was inactivated by forming a merodiploid cointegrate using an internal fragment of the gene within the Ames strain of B. anthracis to construct the mutant strain Ames-JAB1. Carbohydrate analysis of spores from this mutant demonstrated the loss of rhamnose. When assaying for spore infection of macrophages, we detected a significant decrease in the recovery with the Ames-JAB1 strain compared to the recovery with the Ames wild-type strain. When pre-treating macrophages with cytochalasin-D, spores of the mutant were further hindered in recovery, indicating that the spores were not able to bind as well to the macrophages. However, in guinea pigs challenge experiments, no difference in virulence was observed between the mutant and wild-type si rains. These results suggest that the incorporation of rhamnose into the spore coat of B. anthracis is required for optimal interaction with macrophages but is not required for full virulence in this animal model. (C) 2004 Published by Elsevier Ltd.