title: Different regulatory regions are located on the sensor domain of CpxA to fine-tune signal transduction.
abstract: In Gram-negative bacteria, the Cpx signal transduction pathway (CpxAR) has an overall regulatory function, but the mechanism of its activation is still poorly understood. Here we investigated the impact of the periplasmic sensor domain of CpxA on signalling by mutational analysis in vitro. Substitutions (R33C and L38P) in the N-terminal region significantly increased CpxA autophosphorylation, whereas a substitution in a predicted beta sheet (E92K), which impaired the inhibitory effect of the auxiliary CpxP protein, had no significant effect on catalytic activity. Thus, our data suggest different regions on the periplasmic domain of CpxA, which impact to modulate signal transduction.
authors.affiliation: Humboldt Universität zu Berlin, Institut für Biologie, Abteilung Physiologie der Mikroorganismen, Berlin, Germany. r.keller@dundee.ac.uk
authors.forename: Rebecca
authors.initials: R
authors.lastname: Keller
authors.forename: Judith
authors.initials: J
authors.lastname: Havemann
authors.forename: Sabine
authors.initials: S
authors.lastname: Hunke
mesh_terms: D004926:Escherichia coli / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D010766:Phosphorylation; D011494:Protein Kinases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D015398:Signal Transduction
chemical_list: D029968:Escherichia coli Proteins; D011494:Protein Kinases; C490475:CpxA protein, E coli