title: Systematic profiling of the bacterial phosphoproteome reveals bacterium-specific features of phosphorylation.
abstract: Protein phosphorylation is a crucial posttranslational modification for regulating cellular processes in bacteria; however, it has not been extensively studied because of technical difficulties in the enrichment of phosphopeptides. We devised an enrichment protocol that enabled the identification of >1000 phosphopeptides from a single bacterial sample. We discovered three high-confidence serine and threonine phosphorylation motifs, as well as 29 other motifs at various levels of confidence, from three distinct bacterial phosphoproteomes. We found that the proline-directed and basophilic phosphorylation motifs that are commonly enriched in eukaryotes were not observed in bacteria. Unlike eukaryotes, bacteria had a low occurrence of both phosphorylation and acetylation in N-terminal phosphopeptides. Because infection of host cells by bacterial pathogens is often accompanied by kinase-mediated phosphorylation events, the differences in phosphorylation preferences between bacteria and eukaryotes revealed by this study could be useful in identifying bacterial-specific targets for future therapies.
authors.affiliation: Department of Molecular and Cellular Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan.
authors.forename: Miao-Hsia
authors.initials: MH
authors.lastname: Lin
authors.affiliation: Department of Molecular and Cellular Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Sugiyama
authors.affiliation: Department of Molecular and Cellular Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan. yishiham@pharm.kyoto-u.ac.jp.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Ishihama
mesh_terms: D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D007711:Klebsiella pneumoniae / Q000235:genetics / Q000378:metabolism*; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation / Q000502:physiology; D020543:Proteome / Q000235:genetics / Q000378:metabolism*
chemical_list: D029968:Escherichia coli Proteins; D010750:Phosphoproteins; D020543:Proteome