Characterization of degQ and degS, Escherichia coli genes encoding homologs of the DegP protease.

AUTOR(ES)

Waller, P R

RESUMO

The degQ and degS genes of Escherichia coli encode proteins of 455 and 355 residues, respectively, which are homologs of the DegP protease. The purified DegQ protein has the properties of a serine endoprotease and is processed by the removal of a 27-residue amino-terminal signal sequence. A plasmid expressing degQ rescues the temperature-sensitive phenotype of a strain bearing the degP41 deletion, implying that DegQ, like DegP, functions as a periplasmic protease in vivo. Deletions in the degQ gene cause no obvious growth defect, while those in the degS gene result in a small-colony phenotype. The latter phenotype is rescued by a plasmid expressing the degS gene but not by plasmids expressing the degQ or degP genes. This result and the inability of a plasmid expressing degS to rescue the temperature-sensitive degP41 phenotype indicate that the DegS protein is functionally different from the DegQ and DegP proteins.

Documentos Relacionados

• The DegP and DegQ periplasmic endoproteases of Escherichia coli: specificity for cleavage sites and substrate conformation.
• The acylated precursor form of the colicin A lysis protein is a natural substrate of the DegP protease.
• degS Is Necessary for Virulence and Is among Extraintestinal Escherichia coli Genes Induced in Murine Peritonitis
• Escherichia coli DegP Protease Cleaves between Paired Hydrophobic Residues in a Natural Substrate: the PapA Pilin
• Overexpression of Protease-Deficient DegPS210A Rescues the Lethal Phenotype of Escherichia coli OmpF Assembly Mutants in a degP Background