Regulation of the OmpA outer membrane protein of Escherichia coli.

AUTOR(ES)

Beher, M G

RESUMO

The role of lipopolysaccharide in regulating the expression of the ompA outer membrane protein gene of Escherichia coli K-12 was studied by isolating mutants defective in the biosynthesis of lipopolysaccharide and by examining transcription of lacZ in strains carrying operon fusions in which lacZ is expressed from the ompA promoter. By selecting for simultaneous resistance to phages K3 and U3, we obtained mutants defective in rfaC (biosynthesis of core heptose) and in rfaP (phosphorylation of core heptose), and both of these mutant strains failed to express OmpA protein in the outer membrane. Expression of lacZ from the ompA or by foreign ompA alleles which are not expressed in E. coli K-12. Expression was increased in strains carrying rfaC and rfaP mutations. No precursor or degraded form of OmpA protein accumulated in cells which could not express the protein in the outer membrane. This lack of accumulation of precursor was observed even in the presence of phenethyl alcohol, which caused accumulation of OmpA precursor in wild-type cells. We present a model for the regulation of this gene which is consistent with these observations and which involves modulation of transcription coupled to translation of the protein.

Documentos Relacionados

• Major heat-modifiable outer membrane protein in gram-negative bacteria: comparison with the ompA protein of Escherichia coli.
• Bacteriophage receptor area of outer membrane protein OmpA of Escherichia coli K-12.
• Regulatory region of the gene for the ompA protein, a major outer membrane protein of Escherichia coli
• Pseudomonas aeruginosa outer membrane protein F: structural role and relationship to the Escherichia coli OmpA protein.
• Nucleotide sequence of the gene ompA coding the outer membrane protein II of Escherichia coli K-12.