title: A polyphosphate kinase 1 (ppk1) mutant of Pseudomonas aeruginosa exhibits multiple ultrastructural and functional defects.
abstract: Pseudomonas aeruginosa, of medical, environmental, and industrial importance, depends on inorganic polyphosphate (poly P) for a wide range of functions, especially survival. Mutants of PAO1 lacking poly P kinase 1, PPK1, the enzyme responsible for most poly P synthesis in Escherichia coli and other bacteria, are defective in motility, quorum sensing, biofilm formation, and virulence. We describe here multiple defects in the ppk1 mutant PAOM5, including a striking compaction of the nucleoid, distortion of the cell envelope, lack of planktonic motility and exopolymer production, and susceptibility to the beta-lactam antibiotic carbenicillin as well as desiccation. We propose that P. aeruginosa with reduced poly P levels undergoes ultrastructural changes that contribute to profound deficiencies in cellular functions.
authors.affiliation: *Department of Biochemistry, Stanford University School of Medicine, 279 West Campus Drive, Stanford, CA 94305-5307.
authors.forename: Cresson D
authors.initials: CD
authors.lastname: Fraley
authors.forename: M Harunur
authors.initials: MH
authors.lastname: Rashid
authors.forename: Sam S K
authors.initials: SS
authors.lastname: Lee
authors.forename: Rebecca
authors.initials: R
authors.lastname: Gottschalk
authors.forename: Janine
authors.initials: J
authors.lastname: Harrison
authors.forename: Pauline J
authors.initials: PJ
authors.lastname: Wood
authors.forename: Michael R W
authors.initials: MR
authors.lastname: Brown
authors.forename: Arthur
authors.initials: A
authors.lastname: Kornberg
mesh_terms: D002228:Carbenicillin / Q000633:toxicity; D002462:Cell Membrane / Q000648:ultrastructure; D002855:Chromatography, Thin Layer; D008854:Microscopy, Electron; D016296:Mutagenesis; D009154:Mutation / Q000235:genetics*; D017856:Phosphotransferases (Phosphate Group Acceptor) / Q000235:genetics*; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000235:genetics* / Q000648:ultrastructure*
chemical_list: D017856:Phosphotransferases (Phosphate Group Acceptor); C022424:polyphosphate kinase; D002228:Carbenicillin