title: Novel whole-cell antibiotic biosensors for compound discovery.
abstract: Cells containing reporters which are specifically induced via selected promoters are used in pharmaceutical drug discovery and in environmental biology. They are used in screening for novel drug candidates and in the detection of bioactive compounds in environmental samples. In this study, we generated and validated a set of five Bacillus subtilis promoters fused to the firefly luciferase reporter gene suitable for cell-based screening, enabling the as yet most-comprehensive high-throughput diagnosis of antibiotic interference in the major biosynthetic pathways of bacteria: the biosynthesis of DNA by the yorB promoter, of RNA by the yvgS promoter, of proteins by the yheI promoter, of the cell wall by the ypuA promoter, and of fatty acids by the fabHB promoter. The reporter cells mainly represent novel antibiotic biosensors compatible with high-throughput screening. We validated the strains by developing screens with a set of 14,000 pure natural products, representing a source of highly diverse chemical entities, many of them with antibiotic activity (6% with anti-Bacillus subtilis activity of </=25 mug/ml]). Our screening approach is exemplified by the discovery of classical and novel DNA synthesis and translation inhibitors. For instance, we show that the mechanistically underexplored antibiotic ferrimycin A1 selectively inhibits protein biosynthesis.
authors.affiliation: Pharma Research & Development, Discovery Europe, Bayer HealthCare AG, D-42096 Wuppertal, Germany. christoph.freiberg@bayerhealthcare.com
authors.forename: Andreas
authors.initials: A
authors.lastname: Urban
authors.forename: Stefan
authors.initials: S
authors.lastname: Eckermann
authors.forename: Beate
authors.initials: B
authors.lastname: Fast
authors.forename: Susanne
authors.initials: S
authors.lastname: Metzger
authors.forename: Matthias
authors.initials: M
authors.lastname: Gehling
authors.forename: Karl
authors.initials: K
authors.lastname: Ziegelbauer
authors.forename: Helga
authors.initials: H
authors.lastname: Rübsamen-Waigmann
authors.forename: Christoph
authors.initials: C
authors.lastname: Freiberg
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D001426:Bacterial Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D015374:Biosensing Techniques / Q000379:methods*; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D004269:DNA, Bacterial / Q000037:antagonists & inhibitors / Q000378:metabolism; D005227:Fatty Acids / Q000037:antagonists & inhibitors / Q000378:metabolism; D008826:Microbial Sensitivity Tests / Q000379:methods; D011401:Promoter Regions, Genetic; D012329:RNA, Bacterial / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D005227:Fatty Acids; D012329:RNA, Bacterial