Suppressor mutations in ribosomal proteins and FliY restore Bacillus subtilis swarming motility in the absence of EF-P

PLoS Genet. 2019 Jun 25;15(6):e1008179. doi: 10.1371/journal.pgen.1008179. eCollection 2019 Jun.

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.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Bacillus subtilis / genetics
  • Bacterial Proteins / genetics*
  • Cell Movement / genetics
  • Flagella / genetics
  • Membrane Proteins / genetics*
  • Mutation
  • Peptide Elongation Factors / genetics*
  • Protein Biosynthesis*
  • Ribosomal Proteins / genetics
  • Ribosomes / genetics
  • Suppression, Genetic*

Substances

  • Bacterial Proteins
  • Membrane Proteins
  • Peptide Elongation Factors
  • Ribosomal Proteins
  • factor EF-P
  • FliY protein, Bacteria