ROLE OF PROTEIN-F IN MAINTAINING STRUCTURAL INTEGRITY OF THE PSEUDOMONAS-AERUGINOSA OUTER-MEMBRANE
ROLE OF PROTEIN-F IN MAINTAINING STRUCTURAL INTEGRITY OF THE PSEUDOMONAS-AERUGINOSA OUTER-MEMBRANE
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DOI：
10.1128/jb.171.2.983-990.1989
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发表时间：
1989-02-01
影响因子：
3.2
通讯作者：
NISHINO, T
中科院分区：
文献类型：
--
作者：
GOTOH, N;WAKEBE, H;NISHINO, T
为了研究铜绿假单胞菌外膜蛋白F的功能作用，我们分离了缺乏蛋白F的突变体，并通过质粒FP5介导的接合将缺陷基因转移到野生型菌株中。蛋白质F-缺陷的外膜的化学分析表明，外膜蛋白质的量减少到72%至74%的蛋白质F-充足的菌株和脂多糖和磷脂增加到117%至123%和135%至136%，分别。突变体和接合子显示出以下特征：（i）蛋白F缺陷菌株在低渗透压培养基中的生长速率（例如，L肉汤含有0.1%NaCl）是小于1/10的蛋白F-足够的菌株的速率;（ii）蛋白F-缺陷的细胞是圆形的，和外膜形成大的突出的水泡;和（iii）外膜变得物理脆弱，因为大量的周质蛋白泄漏出来，细胞变得高度敏感的渗透压休克。结果表明，蛋白F在形态发生和维持外膜的完整性中起着重要作用。β-Al_2O_3和β-Al_2O_3扩散速率的测定内酰胺类抗生素显示，与蛋白质F充足的外膜相比，蛋白质F缺乏的外膜没有可检测的转运缺陷。抗生素对蛋白F缺乏菌株的MIC与蛋白F充足菌株的MIC几乎相同。
To investigate the functional role of protein F of the outer membrane of Pseudomonas aeruginosa, we isolated mutants devoid of protein F, and the defective gene was transferred to a wild-type strain by plasmid FP5-mediated conjugation. Chemical analyses of the protein F-deficient outer membrane revealed that the amount of outer membrane protein was reduced to 72 to 74% of that of the protein F-sufficient strain and that lipopolysaccharides and phospholipids increased to 117 to 123% and 135 to 136%, respectively. The mutants and the transconjugant showed the following characteristics: (i) growth rates of protein F-deficient strains in low-osmolarity medium (e.g., L broth containing 0.1% NaCl) were less than 1/10 the rate of the protein F-sufficient strain; (ii) protein F-deficient cells were rounded, and the outer membrane formed large protruded blebs; and (iii) the outer membrane became physically fragile, since a significant amount of periplasmic proteins leaked out and the cells became highly sensitive to osmotic shock. The results suggested that protein F plays an important role in morphogenesis and in maintaining the integrity of the outer membrane. Determination of the diffusion rates of saccharides and .beta.-lactam antibiotics showed that the protein F-deficient outer membrane had no detectable transport defect compared with the protein F-sufficient outer membrane. The MICs of antibiotics for the protein F-deficient strains were nearly identical to those for the protein F-sufficient strain.