Role of the ompT mutation in stimulated decrease in colony-forming ability due to intracellular protein aggregate formation in Escherichia coli strain BL21

• Published in: Bioscience, biotechnology, and biochemistry biotechnology, and biochemistry, 2007-02, Vol.71 (2), p.504-512
• Main Authors: Ono, B.(Ritsumeikan Univ., Kusatsu, Shiga (Japan). Faculty of Science and Engineering), Kimiduka, H, Kubota, M, Okuno, K, Yabuta, M
• Format: Article
• Language: English
• Subjects: APTITUD COLONIZADORA; APTITUDE A COLONISER; Bacterial Outer Membrane Proteins - genetics; Bacterial Proteins - biosynthesis; Bacterial Proteins - chemistry; Bacterial Proteins - genetics; Biological and medical sciences; Blotting, Western; Centrifugation, Density Gradient; COLONIZING ABILITY; Colony Count, Microbial; colony-forming ability of E. coli; Congo Red; Culture Media; DNA, Bacterial - chemistry; DNA, Bacterial - genetics; Electrophoresis, Polyacrylamide Gel; ESCHERICHIA COLI; Escherichia coli - genetics; Escherichia coli - growth & development; Escherichia coli - metabolism; Escherichia coli Proteins - genetics; Fundamental and applied biological sciences. Psychology; FUSION DE PROTOPLASTES; FUSION DEL PROTOPLASTO; Glutathione - metabolism; Glycerol - chemistry; MAMIFEROS; MAMMALS; MAMMIFERE; MICROBIAL PROTEINS; Microscopy, Electron, Scanning; Mutation - genetics; OmpT protease; Peptide Hydrolases - genetics; Plasmids - genetics; PRION; PRIONES; PRIONS; PROTEASAS; PROTEASE; PROTEASES; protein polymer formation; protein quality control; PROTEINAS MICROBIANAS; PROTEINE MICROBIENNE; PROTOPLAST FUSION; yeast prion [PSI
• ISSN: 0916-8451; 1347-6947
• DOI: 10.1271/bbb.60541

Recently we found that the cells of Escherichia coli strain BL21 producing a fusion protein, GST-Sup35NM, show a much more rapid decrease in colony-forming ability in the stationary phase than control cells. In this study, it was found that an extract of the cells producing GST-Sup35NM forms fibrous protein polymers containing GST-Sup35NM. In the course of the study, we realized that strain BL21 carried the ompT mutation. We suspected that the deficiency in OmpT protease was responsible for the observed phenotype. To test this, we introduced the wild-type ompT gene into strain BL21, and found that the transformed cells recovered the wild-type phenotype. We concluded that OmpT protease, though known to localize on the cell surface, is involved in protein quality control within the cell.