title: DjlA negatively regulates the Rcs signal transduction system in Escherichia coli.
abstract: The Rcs signal transduction system of Escherichia coli regulating capsular polysaccharide synthesis (cps) genes is activated by overexpression of the djlA gene encoding a cytoplasmic membrane-anchored DnaJ-like protein. However, by monitoring the expression of a cpsB'-lac fusion in pgsA- and mdoH-null mutants in which the Rcs system is activated, we found that the Rcs activity was further increased by deletion of djlA and decreased by low-level extrachromosomal expression of djlA. Furthermore, deletion of djlA in a wild-type strain led to small but significant increase of the basal-level activity of the Rcs system. These results demonstrate that DjlA functions as a negative regulator of the Rcs system unless abnormally overproduced.
authors.affiliation: Department of Biochemistry and Molecular Biology, Faculty of Science, Saitama University, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Shiba
authors.forename: Kouji
authors.initials: K
authors.lastname: Matsumoto
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hara
mesh_terms: D015536:Down-Regulation / Q000502:physiology*; D004926:Escherichia coli / Q000235:genetics / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D050956:HSP40 Heat-Shock Proteins / Q000235:genetics / Q000502:physiology*; D009097:Multienzyme Complexes / Q000378:metabolism*; D010749:Phosphoprotein Phosphatases / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism*; D015398:Signal Transduction / Q000235:genetics* / Q000502:physiology
chemical_list: C494634:DjlA protein, E coli; D029968:Escherichia coli Proteins; D050956:HSP40 Heat-Shock Proteins; D009097:Multienzyme Complexes; C489728:rcsC protein, E coli; C078611:rcsF protein, E coli; D011494:Protein Kinases; D010749:Phosphoprotein Phosphatases