title: Purification of two Bacillus subtilis proteins which cross-react with antibodies directed against eukaryotic protein kinase C, the His HPr kinase and trigger factor.
abstract: As in eukaryotes, phosphorylation of Ser residues in proteins appears to be common phenomenon in bacteria. Surprisingly, however, very few Ser/Thr protein kinases have been identified and in this study antibodies directed against mammalian protein kinase C (PKC) have been used in attempts to isolate conserved Ser/Thr protein kinases. Using the mAb M7 against rat brain PKC, a single 70 kDa band was identified in total cell extracts of Bacillus subtilis by Western blotting after SDS-PAGE, whilst using polyclonal antibody alpha-PKC1p against Saccharomyces cerevisiae PKC a single 67 kDa band was identified by the same procedure. The two proteins were purified independently on the basis of antibody recognition employing two-dimensional gel electrophoresis as a final step, which allowed subsequent microsequencing. The 70 kDa band was thus identified as the phosphoenolpyruvate-dependent His HPr kinase, Enzyme 1 of the phosphotransferase system. This identity was confirmed using a mutant deleted for ptsl, encoding Enzyme 1. The 67 kDa protein was identified as a previously unknown B. subtilis 'trigger factor', homologous to an Escherichia coli protein-folding enzyme, peptidylprolyl cis-trans-isomerase implicated in cell division.
authors.affiliation: Institut de Génétique et Microbiologic, URA 2225, University Paris XI, Bâtiment 409, 91405 Orsay cedex, France.
authors.forename: Naïla
authors.initials: N
authors.lastname: Zouari
authors.affiliation: Institut de Génétique et Microbiologic, URA 2225, University Paris XI, Bâtiment 409, 91405 Orsay cedex, France.
authors.forename: Benoît
authors.initials: B
authors.lastname: Roche
authors.affiliation: Institut de Génétique et Microbiologic, URA 2225, University Paris XI, Bâtiment 409, 91405 Orsay cedex, France.
authors.forename: Jos F M L
authors.initials: JFML
authors.lastname: Seegers
authors.affiliation: Institut de Génétique et Microbiologic, URA 2225, University Paris XI, Bâtiment 409, 91405 Orsay cedex, France.
authors.forename: Simone J
authors.initials: SJ
authors.lastname: Séror
mesh_terms: D000591:Amino Acid Isomerases / Q000235:genetics* / Q000276:immunology; D000595:Amino Acid Sequence; D000818:Animals; D001412:Bacillus subtilis / Q000235:genetics* / Q000276:immunology; D001426:Bacterial Proteins / Q000235:genetics* / Q000276:immunology; D001921:Brain / Q000201:enzymology; D002352:Carrier Proteins / Q000235:genetics* / Q000276:immunology; D003001:Cloning, Molecular; D003429:Cross Reactions; D008969:Molecular Sequence Data; D019696:Peptidylprolyl Isomerase; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000235:genetics* / Q000276:immunology; D017852:Phosphotransferases (Nitrogenous Group Acceptor) / Q000235:genetics* / Q000276:immunology; D011493:Protein Kinase C / Q000235:genetics / Q000276:immunology; D011494:Protein Kinases / Q000235:genetics* / Q000276:immunology; D051381:Rats; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D011494:Protein Kinases; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; D011493:Protein Kinase C; D017852:Phosphotransferases (Nitrogenous Group Acceptor); C022360:phosphoenolpyruvate-protein phosphotransferase; D000591:Amino Acid Isomerases; D019696:Peptidylprolyl Isomerase