title: Arginine phosphorylation marks proteins for degradation by a Clp protease.
abstract: Protein turnover is a tightly controlled process that is crucial for the removal of aberrant polypeptides and for cellular signalling. Whereas ubiquitin marks eukaryotic proteins for proteasomal degradation, a general tagging system for the equivalent bacterial Clp proteases is not known. Here we describe the targeting mechanism of the ClpC-ClpP proteolytic complex from Bacillus subtilis. Quantitative affinity proteomics using a ClpP-trapping mutant show that proteins phosphorylated on arginine residues are selectively targeted to ClpC-ClpP. In vitro reconstitution experiments demonstrate that arginine phosphorylation by the McsB kinase is required and sufficient for the degradation of substrate proteins. The docking site for phosphoarginine is located in the amino-terminal domain of the ClpC ATPase, as resolved at high resolution in a co-crystal structure. Together, our data demonstrate that phosphoarginine functions as a bona fide degradation tag for the ClpC-ClpP protease. This system, which is widely distributed across Gram-positive bacteria, is functionally analogous to the eukaryotic ubiquitin-proteasome system.
authors.affiliation: Research Institute of Molecular Pathology (IMP), Dr-Bohr-Gasse 7, 1030 Vienna, Austria.
authors.forename: Débora Broch
authors.initials: DB
authors.lastname: Trentini
authors.affiliation: Research Institute of Molecular Pathology (IMP), Dr-Bohr-Gasse 7, 1030 Vienna, Austria.
authors.forename: Marcin Józef
authors.initials: MJ
authors.lastname: Suskiewicz
authors.affiliation: Research Institute of Molecular Pathology (IMP), Dr-Bohr-Gasse 7, 1030 Vienna, Austria.
authors.forename: Alexander
authors.initials: A
authors.lastname: Heuck
authors.affiliation: Research Institute of Molecular Pathology (IMP), Dr-Bohr-Gasse 7, 1030 Vienna, Austria.
authors.forename: Robert
authors.initials: R
authors.lastname: Kurzbauer
authors.affiliation: Research Institute of Molecular Pathology (IMP), Dr-Bohr-Gasse 7, 1030 Vienna, Austria.
authors.forename: Luiza
authors.initials: L
authors.lastname: Deszcz
authors.affiliation: Research Institute of Molecular Pathology (IMP), Dr-Bohr-Gasse 7, 1030 Vienna, Austria.|Institute of Molecular Biotechnology of the Austrian Academy of Science (IMBA), Dr-Bohr-Gasse 3, 1030 Vienna, Austria.
authors.forename: Karl
authors.initials: K
authors.lastname: Mechtler
authors.affiliation: Research Institute of Molecular Pathology (IMP), Dr-Bohr-Gasse 7, 1030 Vienna, Austria.
authors.forename: Tim
authors.initials: T
authors.lastname: Clausen
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D001120:Arginine / Q000031:analogs & derivatives* / Q000378:metabolism; D001412:Bacillus subtilis / Q000201:enzymology*; D001426:Bacterial Proteins / Q000378:metabolism*; D001665:Binding Sites; D018360:Crystallography, X-Ray; D049071:Endopeptidase Clp / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D009943:Organophosphorus Compounds / Q000378:metabolism; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism*; D059748:Proteolysis
chemical_list: D001426:Bacterial Proteins; D009943:Organophosphorus Compounds; C015441:phospho-L-arginine; D001120:Arginine; D011494:Protein Kinases; C423322:McsB protein, Bacillus subtilis; D049071:Endopeptidase Clp; D000251:Adenosine Triphosphatases