Characterization of degQ and degS, Escherichia coli genes encoding homologs of the DegP protease.
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.
Waller
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PR
Department of Biology, Massachusetts Institute of Technology, Cambridge 02139, USA.
Sauer
R T
RT
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D002462:Cell Membrane / Q000201:enzymology; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial; D006360:Heat-Shock Proteins; D008969:Molecular Sequence Data; D033903:Periplasmic Proteins; D010641:Phenotype; D012329:RNA, Bacterial / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D017422:Sequence Analysis, DNA; D017384:Sequence Deletion; D017386:Sequence Homology, Amino Acid; D012697:Serine Endopeptidases / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D013489:Suppression, Genetic
D001426:Bacterial Proteins; C066496:DegS protein, Bacteria; D029968:Escherichia coli Proteins; D006360:Heat-Shock Proteins; D033903:Periplasmic Proteins; D012329:RNA, Bacterial; D012333:RNA, Messenger; C489349:degS protein, Escherichia coli; C061682:DegP protease; C098059:DegQ protein, E coli; D012697:Serine Endopeptidases