title: The pss and psd genes are required for motility and chemotaxis in Escherichia coli.
abstract: Mutants of Escherichia coli defective in phosphatidylserine synthase (encoded by pss) and phosphatidylserine decarboxylase (encoded by psd) make cell membranes deficient in phosphatidylethanolamine. In this report we show that wild-type pss and psd genes are required for motility and chemotaxis. Null mutants or strains with temperature-sensitive pss or psd mutations grown at high temperature (35 degrees C) were nonmotile. They lacked flagella and showed reduced rates of transcription of the flhD master operon (encoding FlhD and FlhC), the fliA operon (encoding sigma F), and the fliC operon (encoding flagellin). At low temperature (25 degrees C), the temperature-sensitive mutant cells showed motility and chemotaxis but at reduced levels. The extent of the motility and chemotaxis defects in the mutants was correlated with the amount of phosphatidylethanolamine in the membranes, suggesting a link between membrane phospholipid composition and expression of the flagellum chemotaxis regulon.
authors.affiliation: Department of Molecular and Cell Biology, University of California, Berkeley 94720.
authors.forename: W
authors.initials: W
authors.lastname: Shi
authors.forename: M
authors.initials: M
authors.lastname: Bogdanov
authors.forename: W
authors.initials: W
authors.lastname: Dowhan
authors.forename: D R
authors.initials: DR
authors.lastname: Zusman
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D010717:CDPdiacylglycerol-Serine O-Phosphatidyltransferase / Q000235:genetics*; D002262:Carboxy-Lyases / Q000235:genetics*; D002465:Cell Movement / Q000235:genetics; D002633:Chemotaxis / Q000235:genetics*; D004926:Escherichia coli / Q000502:physiology*; D005407:Flagella / Q000502:physiology*; D005408:Flagellin / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005809:Genes, Regulator; D009154:Mutation; D010714:Phosphatidylethanolamines / Q000096:biosynthesis; D012808:Sigma Factor / Q000235:genetics; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; C064971:FliA protein, Bacteria; D010714:Phosphatidylethanolamines; D012808:Sigma Factor; D005408:Flagellin; D010717:CDPdiacylglycerol-Serine O-Phosphatidyltransferase; D002262:Carboxy-Lyases; C022353:phosphatidylserine decarboxylase