title: Highly phosphorylated bacterial proteins.
abstract: We show in Gram-negative and Gram-positive bacteria the appearance of highly acidic proteins, which are highly phosphorylated. This group of proteins includes many cellular proteins, such as chaperones, biosynthetic, and metabolic enzymes. These proteins accumulate under stress conditions or under conditions, which overload the proteolytic system. Pulse chase experiments using radioactive phosphate indicate that the phosphorylated proteins have a short half-life, suggesting that they could be degradation intermediates. Moreover, results from in vitro experiments in Escherichia coli indicated that ribosomal proteins become susceptible to proteolysis after polyphosphorylation. Therefore, it is possible that the highly phosphorylated proteins represent a group of proteins tagged for degradation by phosphorylation. Such a tagging process may be involved in a general bacterial degradation pathway.
authors.affiliation: Department of Molecular Microbiology and Biotechnology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Ran
authors.initials: R
authors.lastname: Rosen
authors.forename: Dörte
authors.initials: D
authors.lastname: Becher
authors.forename: Knut
authors.initials: K
authors.lastname: Büttner
authors.forename: Dvora
authors.initials: D
authors.lastname: Biran
authors.forename: Michael
authors.initials: M
authors.lastname: Hecker
authors.forename: Eliora Z
authors.initials: EZ
authors.lastname: Ron
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism*; D015153:Blotting, Western; D049109:Cell Proliferation; D030562:Databases, Protein; D015180:Electrophoresis, Gel, Two-Dimensional; D004926:Escherichia coli / Q000378:metabolism; D005838:Genotype; D006863:Hydrogen-Ion Concentration; D015151:Immunoblotting; D047468:Immunoprecipitation; D013058:Mass Spectrometry; D010766:Phosphorylation; D020543:Proteome; D040901:Proteomics; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D020543:Proteome