Requirement of the Pseudomonas aeruginosa tonB Gene for High-Affinity Iron Acquisition and Infection
Requirement of the Pseudomonas aeruginosa tonB Gene for High-Affinity Iron Acquisition and Infection
复制标题
铜绿假单胞菌 tonB 基因高亲和力铁获取和感染的需要
DOI：
10.1128/iai.68.8.4498-4504.2000
复制
发表时间：
2000
影响因子：
3.1
通讯作者：
T. Otani
中科院分区：
文献类型：
--
作者：
H. Takase;H. Nitanai;K. Hoshino;T. Otani
摘要为了研究TonB蛋白对铜绿假单胞菌获得高亲和力铁的贡献，我们构建了来自菌株PAO1及其衍生物的tonB失活突变体，其缺乏产生铁载体绿脓菌荧光素和绿脓菌螯铁蛋白。tonB突变体不能生长在一个自由铁限制的培养基中制备的脱铁转铁蛋白除了，即使培养基中补充了每个纯化的铁载体或血红素源（血红蛋白或氯化血红素）。tonBin活化显示出使铜绿假单胞菌不能用任一铁载体从转铁蛋白获得铁。引入携带完整tonB基因的质粒恢复了PAO 1的tonB突变体在无任何补充物的游离铁限制性培养基中的生长，并恢复了铁载体缺陷衍生物的tonB突变体在补充有绿脓菌荧光素、绿脓菌螯铁蛋白、血红蛋白或氯化血红素的培养基中的生长。此外，动物实验表明，与PAO 1相反，PAO 1的thetonB突变体不能在体内生长，例如在免疫抑制小鼠的肌肉和肺中，并且不能杀死任何动物。在tonB突变体中导入携带tonB的质粒后，体内生长能力和致死毒力也得到恢复。这些结果清楚地表明，完整的tonB基因，因此，由它编码的TonB蛋白质，是必不可少的铁收购介导的绿脓菌荧光素和绿脓菌螯铁蛋白和通过血红素摄取铜绿假单胞菌，并表明TonB依赖性铁收购可能是必不可少的铜绿假单胞菌感染动物宿主。
ABSTRACT To investigate the contribution of the TonB protein to high-affinity iron acquisition in Pseudomonas aeruginosa, we constructed tonB-inactivated mutants from strain PAO1 and its derivative deficient in producing the siderophores pyoverdin and pyochelin. The tonB mutants could not grow in a free-iron-restricted medium prepared by apotransferrin addition, even though the medium was supplemented with each purified siderophore or with a heme source (hemoglobin or hemin). The tonBinactivation was shown to make P. aeruginosa unable to acquire iron from the transferrin with either siderophore. Introduction of a plasmid carrying the intact tonB gene restored growth of the tonB mutant of PAO1 in the free-iron-restricted medium without any supplements and restored growth of thetonB mutant of the siderophore-deficient derivative in the medium supplemented with pyoverdin, pyochelin, hemoglobin, or hemin. In addition, animal experiments showed that, in contrast to PAO1, thetonB mutant of PAO1 could not grow in vivo, such as in the muscles and lungs of immunosuppressed mice, and could not kill any of the animals. The in vivo growth ability and lethal virulence were also restored by introduction of the tonB-carrying plasmid in the tonB mutant. These results indicate clearly that the intact tonB gene—and, therefore, the TonB protein encoded by it—is essential for iron acquisition mediated by pyoverdin and pyochelin and via heme uptake in P. aeruginosa and suggest that the TonB-dependent iron acquisition may be essential for P. aeruginosa to infect the animal host.
DOI：
10.1099/00221287-146-1-185
发表时间：
2000-01-01
期刊：
MICROBIOLOGY-UK
影响因子：
--
作者：
Ochsner, UA;Johnson, Z;Vasil, ML
通讯作者：
Vasil, ML