title: A second type of protein methylation reaction in bacterial chemotaxis.
abstract: CheZ is the product of one of six genes required for sensory processing in Escherichia coli and Salmonella typhimurium chemotaxis. This 24-kDa cytoplasmic protein is modified by a posttranslational methylation reaction. The modified residue has been identified by analysis of radioactively labeled protein from two-dimensional electrophoretograms and Edman degradation of CheZ protein isolated by immunoaffinity chromatography using anti-CheZ monoclonal antibodies. The methylated group is an N-monomethylmethionine residue at the amino terminus of CheZ. L16, a ribosomal protein that is required for peptidyltransferase activity during protein synthesis, is also methylated at its amino-terminal methionine (Chen, R., Brosius, J., and Wittmann-Liebold, B. (1977) J. Mol. Biol. 111, 173-181). Homologous sequences at the amino termini of L16 and CheZ raise the possibility that a single S-adenosylmethionine-dependent methyltransferase modifies both proteins.
authors.forename: A
authors.initials: A
authors.lastname: Stock
authors.forename: E
authors.initials: E
authors.lastname: Schaeffer
authors.forename: D E
authors.initials: DE
authors.lastname: Koshland
authors.forename: J
authors.initials: J
authors.lastname: Stock
mesh_terms: D001426:Bacterial Proteins; D002630:Chemotactic Factors / Q000378:metabolism*; D002633:Chemotaxis; D005796:Genes; D005798:Genes, Bacterial; D008565:Membrane Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D000072236:Methyl-Accepting Chemotaxis Proteins; D008745:Methylation; D012486:Salmonella typhimurium / Q000235:genetics / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins; D002630:Chemotactic Factors; D008565:Membrane Proteins; D000072236:Methyl-Accepting Chemotaxis Proteins