Role of protein F in maintaining structural integrity of the Pseudomonas aeruginosa outer membrane
Autor: | Naomasa Gotoh, Hirokazu Wakebe, Takeshi Nishino, T Nakae, E Yoshihara |
---|---|
Rok vydání: | 1989 |
Předmět: |
Osmotic shock
Mutant Porins Biology Microbiology Cell membrane Gene product medicine Outer membrane efflux proteins Molecular Biology Strain (chemistry) Cell Membrane Microscopy Electron medicine.anatomical_structure Genes Biochemistry Genes Bacterial Conjugation Genetic Mutation Pseudomonas aeruginosa Biophysics Virulence-related outer membrane protein family Bacterial outer membrane Research Article Bacterial Outer Membrane Proteins Plasmids |
Zdroj: | Journal of Bacteriology. 171:983-990 |
ISSN: | 1098-5530 0021-9193 |
Popis: | 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. |
Databáze: | OpenAIRE |
Externí odkaz: |