Role of lipopolysaccharide in assembly of Escherichia coli outer membrane proteins OmpA, OmpC, and OmpF.
AUTOR(ES)
Ried, G
RESUMO
Selection was performed for resistance to a phage, Ox2, specific for the Escherichia coli outer membrane protein OmpA, under conditions which excluded recovery of ompA mutants. All mutants analyzed produced normal quantities of OmpA, which was also normally assembled in the outer membrane. They had become essentially resistant to OmpC and OmpF-specific phages and synthesized these outer membrane porins at much reduced rates. The inhibition of synthesis acted at the level of translation. This was due to the presence of lipopolysaccharides (LPS) with defective core oligosaccharides. Cerulenin blocks fatty acid synthesis and therefore that of LPS. It also inhibits synthesis of OmpC and OmpF but not of OmpA (C. Bocquet-Pagès, C. Lazdunski, and A. Lazdunski, Eur. J. Biochem. 118:105-111, 1981). In the presence of the antibiotic, OmpA synthesis and membrane incorporation remained unaffected at a time when OmpC and OmpF synthesis had almost ceased. The similarity of these results with those obtained with the mutants suggests that normal porin synthesis is not only interfered with by production of mutant LPS but also requires de novo synthesis of LPS. Since synthesis and assembly of OmpA into the outer membrane was not affected in the mutants or in the presence of cerulenin, association of this protein with LPS appears to occur with outer membrane-located LPS.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=526928Documentos Relacionados
- Promoter exchange between ompF and ompC, genes for osmoregulated major outer membrane proteins of Escherichia coli K-12.
- Mutation causing overproduction of outer membrane protein OmpF and suppression of OmpC synthesis in Escherichia coli.
- Regulatory mutations conferring constitutive synthesis of major outer membrane proteins (OmpC and OmpF) in Escherichia coli.
- Lactoferrin binds to porins OmpF and OmpC in Escherichia coli.
- Regulation of outer membrane protein synthesis in Escherichia coli K-12: deletion of ompC affects expression of the OmpF protein.
