Both chemotaxis and net motility greatly influence the infectivity of Vibrio cholerae
Both chemotaxis and net motility greatly influence the infectivity of Vibrio cholerae
复制标题
DOI：
10.1073/pnas.0308052101
复制
发表时间：
2004-04-06
影响因子：
11.1
通讯作者：
Camilli, A
中科院分区：
文献类型：
--
作者：
Butler, SM;Camilli, A
趋化作用在胃肠道病原体的毒力是不明确的。与直觉相反，极性鞭毛病原菌霍乱弧菌的非趋化突变体在小肠感染期间大大超过了野生型菌株。我们表明，竞争表型依赖于鞭毛旋转的方向，独立于毒素共同调节的毛功能。具体地说，与趋化性丧失相关的竞争需要细菌逆时针倾斜的鞭毛旋转和平滑的直线运动。相比之下，鞭毛旋转顺时针偏倚的非趋化菌株仅限于小规模的净运动，并因感染而减弱。外竞争表型的重要性进行了检验，并显示出与感染性的真正增加相关。逆时针偏倚突变体在幼鼠小肠中异常分布，我们发现毒力因子的表达在所有片段中正常发生。因此，改变霍乱弧菌的趋化特性使其能够利用宿主肠道中的其他生态位。
The role of chemotaxis in the virulence of gastrointestinal pathogens is ill defined. Counterintuitively, nonchemotactic mutants of the polarly flagellated pathogen Vibrio cholerae greatly out-compete the wild-type strain during infection of the small intestine. We show that the out-competition phenotype is dependent on the direction of flagellar rotation and independent of Toxin Co-regulated Pilus function. Specifically, the out-competition associated with the loss of chemotaxis required the presence of counterclockwise-biased flagellar rotation and smooth straight runs by the bacteria. In contrast, a nonchemotactic strain with clockwise-biased of flagellar rotation was confined to small-scale net movement and was attenuated for infection. The significance of the out-competition phenotype was examined and was shown to correlate with a true increase in infectivity. Counterclockwise-biased mutants are aberrantly distributed throughout the infant mouse small intestine and we find that the expression of virulence factors occurs normally in all segments. Thus, alteration of the chemotactic properties of V. cholerae allows it to exploit additional niches in the host intestine.