title: A New Natural Product Analog of Blasticidin S Reveals Cellular Uptake Facilitated by the NorA Multidrug Transporter.
abstract: The permeation of antibiotics through bacterial membranes to their target site is a crucial determinant of drug activity but in many cases remains poorly understood. During screening efforts to discover new broad-spectrum antibiotic compounds from marine sponge samples, we identified a new analog of the peptidyl nucleoside antibiotic blasticidin S that exhibited up to 16-fold-improved potency against a range of laboratory and clinical bacterial strains which we named P10. Whole-genome sequencing of laboratory-evolved strains ofStaphylococcus aureusresistant to blasticidin S and P10, combined with genome-wide assessment of the fitness of barcodedEscherichia coliknockout strains in the presence of the antibiotics, revealed that restriction of cellular access was a key feature in the development of resistance to this class of drug. In particular, the gene encoding the well-characterized multidrug efflux pump NorA was found to be mutated in 69% of allS. aureusisolates resistant to blasticidin S or P10. Unexpectedly, resistance was associated with inactivation ofnorA, suggesting that the NorA transporter facilitates cellular entry of peptidyl nucleosides in addition to its known role in the efflux of diverse compounds, including fluoroquinolone antibiotics.
authors.affiliation: Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Jack R
authors.initials: JR
authors.lastname: Davison
authors.affiliation: Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Katheryn M
authors.initials: KM
authors.lastname: Lohith
authors.affiliation: Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Xiaoning
authors.initials: X
authors.lastname: Wang
authors.affiliation: Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Kostyantyn
authors.initials: K
authors.lastname: Bobyk
authors.affiliation: Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Sivakoteswara R
authors.initials: SR
authors.lastname: Mandadapu
authors.affiliation: Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Su-Lin
authors.initials: SL
authors.lastname: Lee
authors.affiliation: Department of Biochemistry, McGill University, Montreal, Canada.
authors.forename: Regina
authors.initials: R
authors.lastname: Cencic
authors.affiliation: University of Minnesota-Twin Cities, Bioinformatics and Computational Biology Program, Minneapolis, Minnesota, USA.
authors.forename: Justin
authors.initials: J
authors.lastname: Nelson
authors.affiliation: University of Minnesota-Twin Cities, Bioinformatics and Computational Biology Program, Minneapolis, Minnesota, USA.
authors.forename: Scott
authors.initials: S
authors.lastname: Simpkins
authors.affiliation: NIH Clinical Center, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Karen M
authors.initials: KM
authors.lastname: Frank
authors.affiliation: Department of Biochemistry, McGill University, Montreal, Canada.
authors.forename: Jerry
authors.initials: J
authors.lastname: Pelletier
authors.affiliation: University of Minnesota-Twin Cities, Department of Computer Science and Engineering, Minneapolis, Minnesota, USA.
authors.forename: Chad L
authors.initials: CL
authors.lastname: Myers
authors.affiliation: Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA.
authors.forename: Jeff
authors.initials: J
authors.lastname: Piotrowski
authors.affiliation: Genomics Core, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Harold E
authors.initials: HE
authors.lastname: Smith
authors.affiliation: Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA caroleb@mail.nih.gov.
authors.forename: Carole A
authors.identifier: 0000-0003-2203-0852
authors.initials: CA
authors.lastname: Bewley
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001692:Biological Transport / Q000235:genetics / Q000502:physiology; D019450:Genes, MDR / Q000235:genetics / Q000502:physiology; D008826:Microbial Sensitivity Tests; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000235:genetics / Q000378:metabolism; D009705:Nucleosides / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000187:drug effects / Q000235:genetics / Q000472:pathogenicity
chemical_list: D001426:Bacterial Proteins; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D009705:Nucleosides; C004500:blasticidin S
keywords: antibiotic resistance; chemical genomics; natural products; transporters