title: Translation elongation factor EF-P alleviates ribosome stalling at polyproline stretches.
abstract: Translation elongation factor P (EF-P) is critical for virulence in bacteria. EF-P is present in all bacteria and orthologous to archaeal and eukaryotic initiation factor 5A, yet the biological function has so far remained enigmatic. Here, we demonstrate that EF-P is an elongation factor that enhances translation of polyproline-containing proteins: In the absence of EF-P, ribosomes stall at polyproline stretches, whereas the presence of EF-P alleviates the translational stalling. Moreover, we demonstrate the physiological relevance of EF-P to fine-tune the expression of the polyproline-containing pH receptor CadC to levels necessary for an appropriate stress response. Bacterial, archaeal, and eukaryotic cells have hundreds to thousands of polyproline-containing proteins of diverse function, suggesting that EF-P and a/eIF-5A are critical for copy-number adjustment of multiple pathways across all kingdoms of life.
authors.affiliation: Center for Integrated Protein Science Munich (CiPSM), Ludwig-Maximilians-Universität München, Munich, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Ude
authors.forename: Jürgen
authors.initials: J
authors.lastname: Lassak
authors.forename: Agata L
authors.initials: AL
authors.lastname: Starosta
authors.forename: Tobias
authors.initials: T
authors.lastname: Kraxenberger
authors.forename: Daniel N
authors.initials: DN
authors.lastname: Wilson
authors.forename: Kirsten
authors.initials: K
authors.lastname: Jung
mesh_terms: D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000096:biosynthesis* / Q000235:genetics; D006863:Hydrogen-Ion Concentration; D010441:Peptide Chain Elongation, Translational; D010445:Peptide Elongation Factors / Q000235:genetics / Q000378:metabolism*; D010455:Peptides / Q000235:genetics / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism*; D013312:Stress, Physiological; D015534:Trans-Activators / Q000096:biosynthesis* / Q000235:genetics
chemical_list: C087479:CadC protein, E coli; D029968:Escherichia coli Proteins; D010445:Peptide Elongation Factors; D010455:Peptides; D015534:Trans-Activators; C020746:factor EF-P; C011083:polyproline