Abstract
Translation elongation factor P (EF-P) alleviates ribosome pausing at a subset of motifs encoding consecutive proline residues, and is required for growth in many organisms. Here we show that Bacillus subtilis EF-P also alleviates ribosome pausing at sequences encoding tandem prolines and ribosomes paused within several essential genes without a corresponding growth defect in an efp mutant. The B. subtilis efp mutant is instead impaired for flagellar biosynthesis which results in the abrogation of a form of motility called swarming. We isolate swarming suppressors of efp and identify mutations in 8 genes that suppressed the efp mutant swarming defect, many of which encode conserved ribosomal proteins or ribosome-associated factors. One mutation abolished a translational pause site within the flagellar C-ring component FliY to increase flagellar number and restore swarming motility in the absence of EF-P. Our data support a model wherein EF-P-alleviation of ribosome pausing may be particularly important for macromolecular assemblies like the flagellum that require precise protein stoichiometries.
Highlights
Translation elongation factor P (EF-P) is a highly conserved protein that alleviates ribosome pausing at consecutive proline residues
We show that EF-P enhances flagellar biosynthesis by alleviating ribosome pausing within a single flagellar structural component FliY and we implicate the RNA polymerase pausing factor NusG in long operon expression
Translation elongation factor P (EF-P) has been shown to alleviate ribosome pausing at consecutive proline residues (XPPX motifs) in Bacteria and Eukaryotes [1,2,3]
Summary
Translation elongation factor P (EF-P) has been shown to alleviate ribosome pausing at consecutive proline residues (XPPX motifs) in Bacteria and Eukaryotes [1,2,3]. In Escherichia coli, the manner in which EF-P promotes growth is thought to be pleiotropic by enhancing translation of multiple proteins that contain XPPX motifs [7]. Systemslevel approaches, show that not all XPPX motifs induce ribosome pausing in the absence of EF-P, and that even fewer of those pauses result in decreased protein expression [8,9,10]. Consistent with limited pleiotropy, the phenotypes of an efp mutant in E. coli are conditional, and are suppressed when translation rates are reduced [11]. Apparent pleiotropy is organism-specific as growth defects in Bacillus subtilis efp mutants are negligible, even under conditions of high translation [12]. EF-P in B. subtilis is required for swarming motility [12,13]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
