title: Investigation of transphosphorylation between chemotaxis proteins and the phosphoenolpyruvate:sugar phosphotransferase system.
abstract: Transphosphorylation between the chemotaxis proteins and phosphoenolpyruvate:sugar phosphotransferase system (PTS) from Escherichia coli was investigated by incubating the CheA, CheW and CheY proteins of the chemotaxis cascade, and Enzyme I, HPr and Enzyme IImtl of the PTS with [gamma-32P]ATP or [32P]phosphoenolpyruvate in the presence and absence of cell extract. In the absence of cell extract, ATP phosphorylated CheA, but in the presence of cell extract, Enzyme I was also phosphorylated. Phosphoenolpyruvate phosphorylated only PTS components. The transphosphorylation of Enzyme I by ATP did not require chemotaxis proteins, and likely occurred through acetate kinase. Regardless of phosphorylation state, the HPr protein did not inhibit the rate of ATP-dependent phosphorylation of the CheA or the CheY protein. It is concluded that chemotaxis to PTS substrates is not mediated by transphosphorylation between the PTS and chemotaxis systems.
authors.affiliation: Department of Microbiology and Molecular Genetics, Loma Linda University, CA 92350, USA.
authors.forename: M S
authors.initials: MS
authors.lastname: Johnson
authors.forename: E H
authors.initials: EH
authors.lastname: Rowsell
authors.forename: B L
authors.initials: BL
authors.lastname: Taylor
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D002633:Chemotaxis; D004926:Escherichia coli / Q000201:enzymology / Q000502:physiology; D029968:Escherichia coli Proteins; D000071677:Histidine Kinase; D008565:Membrane Proteins / Q000378:metabolism*; D000072236:Methyl-Accepting Chemotaxis Proteins; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000378:metabolism*; D010766:Phosphorylation; D012486:Salmonella typhimurium / Q000201:enzymology / Q000502:physiology
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D000072236:Methyl-Accepting Chemotaxis Proteins; C000607606:cheY protein, E coli; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; C030182:phosphocarrier protein HPr; D000071677:Histidine Kinase; C000607608:cheA protein, E coli