title: Antibiotic Resistance Markers in Burkholderia pseudomallei Strain Bp1651 Identified by Genome Sequence Analysis.
abstract: Burkholderia pseudomalleiBp1651 is resistant to several classes of antibiotics that are usually effective for treatment of melioidosis, including tetracyclines, sulfonamides, and β-lactams such as penicillins (amoxicillin-clavulanic acid), cephalosporins (ceftazidime), and carbapenems (imipenem and meropenem). We sequenced, assembled, and annotated the Bp1651 genome and analyzed the sequence using comparative genomic analyses with susceptible strains, keyword searches of the annotation, publicly available antimicrobial resistance prediction tools, and published reports. More than 100 genes in the Bp1651 sequence were identified as potentially contributing to antimicrobial resistance. Most notably, we identified three previously uncharacterized point mutations inpenA, which codes for a class A β-lactamase and was previously implicated in resistance to β-lactam antibiotics. The mutations result in amino acid changes T147A, D240G, and V261I. When individually introduced into select agent-excludedB. pseudomalleistrain Bp82, D240G was found to contribute to ceftazidime resistance and T147A contributed to amoxicillin-clavulanic acid and imipenem resistance. This study provides the first evidence that mutations inpenAmay alter susceptibility to carbapenems inB. pseudomalleiAnother mutation of interest was a point mutation affecting the dihydrofolate reductase genefolA, which likely explains the trimethoprim resistance of this strain. Bp1651 was susceptible to aminoglycosides likely because of a frameshift in theamrBgene, the transporter subunit of the AmrAB-OprA efflux pump. These findings expand the role ofpenAto include resistance to carbapenems and may assist in the development of molecular diagnostics that predict antimicrobial resistance and provide guidance for treatment of melioidosis.
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, USA jbugrysheva@cdc.gov.
authors.forename: Julia V
authors.initials: JV
authors.lastname: Bugrysheva
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
authors.forename: David
authors.initials: D
authors.lastname: Sue
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
authors.forename: Jay E
authors.initials: JE
authors.lastname: Gee
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
authors.forename: Mindy G
authors.initials: MG
authors.lastname: Elrod
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
authors.forename: Alex R
authors.initials: AR
authors.lastname: Hoffmaster
authors.affiliation: Department of Molecular Genetics and Microbiology, Emerging Pathogens Institute, University of Florida, Gainesville, Florida, USA.
authors.forename: Linnell B
authors.initials: LB
authors.lastname: Randall
authors.affiliation: Department of Molecular Genetics and Microbiology, Emerging Pathogens Institute, University of Florida, Gainesville, Florida, USA.
authors.forename: Sunisa
authors.initials: S
authors.lastname: Chirakul
authors.affiliation: Department of Molecular Genetics and Microbiology, Emerging Pathogens Institute, University of Florida, Gainesville, Florida, USA.
authors.forename: Apichai
authors.initials: A
authors.lastname: Tuanyok
authors.affiliation: Department of Molecular Genetics and Microbiology, Emerging Pathogens Institute, University of Florida, Gainesville, Florida, USA.
authors.forename: Herbert P
authors.initials: HP
authors.lastname: Schweizer
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
authors.forename: Linda M
authors.initials: LM
authors.lastname: Weigel
mesh_terms: D019980:Amoxicillin-Potassium Clavulanate Combination / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D016957:Burkholderia pseudomallei / Q000145:classification / Q000187:drug effects* / Q000235:genetics*; D002442:Ceftazidime / Q000494:pharmacology; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D016680:Genome, Bacterial / Q000235:genetics; D006801:Humans; D015378:Imipenem / Q000494:pharmacology*; D008554:Melioidosis / Q000188:drug therapy / Q000382:microbiology; D026901:Membrane Transport Proteins / Q000235:genetics; D008826:Microbial Sensitivity Tests; D017422:Sequence Analysis, DNA; D013762:Tetrahydrofolate Dehydrogenase / Q000235:genetics; D014295:Trimethoprim / Q000494:pharmacology; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D026901:Membrane Transport Proteins; D015378:Imipenem; D019980:Amoxicillin-Potassium Clavulanate Combination; D002442:Ceftazidime; D014295:Trimethoprim; D013762:Tetrahydrofolate Dehydrogenase; D001618:beta-Lactamases
keywords: Burkholderia pseudomallei; antimicrobial resistance; genome sequence; penA