RRC ID 4980
Author Ninnis RL, Spall SK, Talbo GH, Truscott KN, Dougan DA.
Title Modification of PATase by L/F-transferase generates a ClpS-dependent N-end rule substrate in Escherichia coli.
Journal EMBO J.
Abstract The N-end rule pathway is conserved from bacteria to man and determines the half-life of a protein based on its N-terminal amino acid. In Escherichia coli, model substrates bearing an N-degron are recognised by ClpS and degraded by ClpAP in an ATP-dependent manner. Here, we report the isolation of 23 ClpS-interacting proteins from E. coli. Our data show that at least one of these interacting proteins--putrescine aminotransferase (PATase)--is post-translationally modified to generate a primary N-degron. Remarkably, the N-terminal modification of PATase is generated by a new specificity of leucyl/phenylalanyl-tRNA-protein transferase (LFTR), in which various combinations of primary destabilising residues (Leu and Phe) are attached to the N-terminal Met. This modification (of PATase), by LFTR, is essential not only for its recognition by ClpS, but also determines the stability of the protein in vivo. Thus, the N-end rule pathway, through the ClpAPS-mediated turnover of PATase may have an important function in putrescine homeostasis. In addition, we have identified a new element within the N-degron, which is required for substrate delivery to ClpA.
Volume 28(12)
Pages 1732-44
Published 2009-6-17
DOI 10.1038/emboj.2009.134
PII emboj2009134
PMID 19440203
PMC PMC2699360
MeSH Amino Acid Motifs Amino Acid Sequence Aminoacyltransferases / metabolism* Bacterial Outer Membrane Proteins / metabolism Carrier Proteins / chemistry Carrier Proteins / metabolism* Chromatography, Affinity Dipeptides / metabolism Endopeptidase Clp / chemistry Endopeptidase Clp / metabolism Escherichia coli / enzymology* Escherichia coli Proteins / chemistry Escherichia coli Proteins / metabolism* Hydrophobic and Hydrophilic Interactions Ligands Metabolic Networks and Pathways* Models, Biological Molecular Sequence Data Mutant Proteins / metabolism Protein Binding Protein Processing, Post-Translational* Substrate Specificity Transaminases / metabolism*
IF 10.557
Times Cited 46
Prokaryotes E. coli ME9062(BW25113) JW0866 JW0865 JW0427 JW0868 JW0797 JW5510