title: Twitching motility and cAMP levels: signal transduction through a single methyl-accepting chemotaxis protein.
abstract: The Pseudomonas aeruginosa Chp chemosensory system regulates twitching motility, intracellular adenosine 3('') 5(')-cyclic monophosphate (cAMP) levels and is postulated to be involved in directional twitching towards phosphatidylethanolamine (PE). Because PilJ is the only methyl-accepting chemotaxis protein (MCP) identified in the Chp system, we determined the role of PilJ in mediating signal transduction for the distinct outputs of this system. Mutants that lack the periplasmic domain of PilJ (pilJΔ74-273) showed lower levels of cAMP but retained directional twitching towards PE. While initial studies revealed reduced twitching motility by PilJΔ74-273, this was due to decreased cAMP levels. Our data illustrate the importance of the periplasmic domain of PilJ in regulating cAMP. This is the first time a defined domain within PilJ has been identified as having a distinct role in signal transduction.
authors.affiliation: Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA.
authors.forename: Vibhuti H
authors.initials: VH
authors.lastname: Jansari
authors.affiliation: Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA.
authors.forename: Vishwakanth Y
authors.initials: VY
authors.lastname: Potharla
authors.affiliation: Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA.
authors.forename: Geoff T
authors.initials: GT
authors.lastname: Riddell
authors.affiliation: Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA bardy@uwm.edu.
authors.forename: Sonia L
authors.initials: SL
authors.lastname: Bardy
mesh_terms: D002633:Chemotaxis; D000242:Cyclic AMP / Q000378:metabolism*; D036781:Fimbriae Proteins / Q000235:genetics / Q000378:metabolism*; D010861:Fimbriae, Bacterial; D000072236:Methyl-Accepting Chemotaxis Proteins / Q000378:metabolism*; D009068:Movement; D009154:Mutation; D010714:Phosphatidylethanolamines; D011550:Pseudomonas aeruginosa / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D015398:Signal Transduction
chemical_list: D000072236:Methyl-Accepting Chemotaxis Proteins; D010714:Phosphatidylethanolamines; C086591:pilJ protein, Pseudomonas aeruginosa; D036781:Fimbriae Proteins; C483858:phosphatidylethanolamine; D000242:Cyclic AMP
keywords: PilJ; Pseudomonas aeruginosa; cAMP; chemotaxis; signal transduction; twitching motility