title: Escherichia coli persister cells suppress translation by selectively disassembling and degrading their ribosomes.
abstract: Bacterial persisters are rare, phenotypically distinct cells that survive exposure to multiple antibiotics. Previous studies indicated that formation and maintenance of the persister phenotype are regulated by suppressing translation. To examine the mechanism of this translational suppression, we developed novel methodology to rapidly purify ribosome complexes from persister cells. We purified His-tagged ribosomes from Escherichia coli cells that over-expressed HipA protein, which induces persister formation, and were treated with ampicillin to remove antibiotic-sensitive cells. We profiled ribosome complexes and analyzed the ribosomal RNA and protein components from these persister cells. Our results show that (i) ribosomes in persisters exist largely as inactive ribosomal subunits, (ii) rRNAs and tRNAs are mostly degraded and (iii) a small fraction of the ribosomes remain mostly intact, except for reduced amounts of seven ribosomal proteins. Our findings explain the basis for translational suppression in persisters and suggest how persisters survive exposure to multiple antibiotics.
authors.affiliation: Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, 74078, USA.
authors.forename: Junho
authors.initials: J
authors.lastname: Cho
authors.forename: Janet
authors.initials: J
authors.lastname: Rogers
authors.forename: Mark
authors.initials: M
authors.lastname: Kearns
authors.forename: Macall
authors.initials: M
authors.lastname: Leslie
authors.forename: Steven D
authors.initials: SD
authors.lastname: Hartson
authors.forename: Kevin S
authors.initials: KS
authors.lastname: Wilson
mesh_terms: D000667:Ampicillin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism*; D014176:Protein Biosynthesis; D012329:RNA, Bacterial / Q000378:metabolism; D012335:RNA, Ribosomal / Q000378:metabolism; D012343:RNA, Transfer / Q000378:metabolism; D012269:Ribosomal Proteins / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D029968:Escherichia coli Proteins; D012329:RNA, Bacterial; D012335:RNA, Ribosomal; D012269:Ribosomal Proteins; D000667:Ampicillin; D012343:RNA, Transfer