ToxR regulates virulence gene expression in non-O1 strains of Vibrio cholerae that cause epidemic cholera
ToxR regulates virulence gene expression in non-O1 strains of Vibrio cholerae that cause epidemic cholera
复制标题
ToxR 调节引起流行性霍乱的非 O1 霍乱弧菌毒力基因表达
作者：
M. Waldor;J. Mekalanos
霍乱弧菌 O1 血清群历来被认为是流行性霍乱的唯一原因。 O139 是一种新的霍乱弧菌血清群，于 1992 年最后几个月出现在印度次大陆，是第一个引起流行性霍乱的非 O1 霍乱弧菌血清群。我们研究了霍乱弧菌经典菌株和 El Tor O1 菌株的一些已知毒力因子在 O139 菌株临床分离株中的表达。我们发现，与其他非 O1 菌株相比，O139 菌株表达 TcpA，这是 O1 菌株中发现的毒素共调节菌毛的主要亚基。与 O1 菌株一样，O139 菌株中霍乱毒素和 TcpA 的表达受到环境参数的协调调节。构建了含有 toxR 无效突变的 O139 菌株的衍生物，并用于证明 O139 菌株中霍乱毒素、TcpA 和外膜蛋白 OmpU 的表达（与 O1 菌株中一样）依赖于 ToxR。两种证据表明 O139 菌株与霍乱弧菌 El Tor 菌株密切相关。首先，O139 和 El Tor 菌株都具有 tcpA 限制性片段长度多态性，这将 El Tor 菌株与霍乱弧菌经典菌株区分开来。其次，培养条件大大增强了 O139 菌株中霍乱毒素的产生，之前已证明培养条件可以促进 El Tor 菌株而非霍乱弧菌经典菌株中霍乱毒素的产生。尽管 O139 是霍乱弧菌的一种新血清型，但 O139 菌株符合从 O1 菌株研究中演变而来的一个基本主题：ToxR 介导毒力基因表达的协调调节。
Vibrio cholerae serogroup O1 has historically been thought to be the exclusive cause of epidemic cholera. O139 is a novel serogroup of V. cholerae which emerged on the Indian subcontinent in the last few months of 1992 and is the first non-O1 serogroup of V. cholerae to cause epidemic cholera. We have investigated the expression of some of the known virulence factors of classical and El Tor O1 strains of V. cholerae in clinical isolates of O139 strains. We show that, in contrast to other non-O1 strains, O139 strains express TcpA, the major subunit of the toxin-coregulated pilus found in O1 strains. As in O1 strains, the expression of cholera toxin and TcpA is coordinately regulated by environmental parameters in O139 strains. Derivatives of O139 strains that contain a toxR null mutation were constructed and used to demonstrate that the expression of cholera toxin, TcpA, and the outer membrane protein OmpU in O139 strains, as in O1 strains, is dependent on ToxR. Two kinds of evidence suggest that O139 strains are closely related to El Tor strains of V. cholerae. First, both O139 and El Tor strains share a restriction fragment length polymorphism for tcpA, which distinguishes El Tor from classical strains of V. cholerae. Second, cholera toxin production in O139 strains is greatly enhanced by culture conditions that have been previously shown to promote production of cholera toxin in El Tor strains and not in classical strains of V. cholerae. Although O139 is a novel serotype of V. cholerae, O139 strains conform to a fundamental theme that has evolved from the study of O1 strains: ToxR mediates coordinate regulation of virulence gene expression.
霍乱肠毒素（choleragen）。
影响因子：
13.5
作者：
Finkelstein,RA;Dorner,F
通讯作者：
Dorner,F
DOI：
10.1073/pnas.81.11.3471
发表时间：
1984-01-01
期刊：
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA-BIOLOGICAL SCIENCES
影响因子：
--
作者：
MILLER, VL;MEKALANOS, JJ
通讯作者：
MEKALANOS, JJ
DOI：
10.1073/pnas.84.9.2833
发表时间：
1987-05-01
影响因子：
11.1
作者：
TAYLOR, RK;MILLER, VL;MEKALANOS, JJ
通讯作者：
MEKALANOS, JJ