plasmids
Mechanisms of ResistanceA Novel Transferable Resistance-Nodulation-Division Pump Gene Cluster, tmexCD2-toprJ2, Confers Tigecycline Resistance in Raoultella ornithinolyticaWe recently identified a novel plasmid-mediated resistance-nodulation-division (RND)-type efflux pump gene cluster, tmexCD1-toprJ1, in Klebsiella pneumoniae that conferred resistance to multiple antimicrobials, including tigecycline. While homologs of tmexCD1-toprJ1 were found encoded in many other bacterial species in GenBank, their functions and...
Mechanisms of ResistanceBKC-2, a New BKC Variant Detected in MCR-9.1-Producing Enterobacter hormaechei subsp. xiangfangensisWe characterized a multidrug-resistant (MDR) Enterobacter spp. isolate highlighting the genetic aspects of the antimicrobial resistance genes. An Enterobacter spp. isolate (Ec61) was recovered in 2014 from a transtracheal aspirate sample from a patient admitted to a Brazilian tertiary hospital and submitted to further microbiological and genomic characterization.
Mechanisms of ResistanceSimulating the Influence of Conjugative-Plasmid Kinetic Values on the Multilevel Dynamics of Antimicrobial Resistance in a Membrane Computing ModelBacterial plasmids harboring antibiotic resistance genes are critical in the spread of antibiotic resistance. It is known that plasmids differ in their kinetic values, i.e., conjugation rate, segregation rate by copy number incompatibility with related plasmids, and rate of stochastic loss during replication. They also differ in cost to the cell in terms of reducing fitness and in the frequency of compensatory mutations compensating...
Epidemiology and SurveillanceComparative Genomic Analysis of Third-Generation-Cephalosporin-Resistant Escherichia coli Harboring the blaCMY-2-Positive IncI1 Group, IncB/O/K/Z, and IncC Plasmids Isolated from Healthy Broilers in JapanThe off-label use of third-generation cephalosporins (3GCs) during in ovo vaccination or vaccination of newly hatched chicks has been a common practice worldwide. CMY-2-producing Escherichia coli strains have been disseminated in broiler chicken production. The objective of this study was to determine the epidemiological linkage of blaCMY-2...
Mechanisms of ResistanceLoss of mcr Genes Mediated by Plasmid Elimination and ISApl1We characterized the stability of a plasmid pCP53-mcr1_3 encoding mcr-1 and mcr-3.19 with and without colistin exposure during cultural passages via S1-pulsed-field gel electrophoresis (PFGE) and nanopore MinION sequencing. Both mcr-1 and mcr-3.19 were missing in certain subclones, mediated by genetic excision (ISApl1-mcr-1-pap2), and deletions of large multidrug resistance (MDR) regions...
Epidemiology and SurveillanceThe Arginine Deiminase Operon Is Responsible for a Fitness Trade-Off in Extended-Spectrum-β-Lactamase-Producing Strains of Escherichia coliWe previously identified an operon involved in an arginine deiminase (ADI) pathway (arc operon) on a CTX-M-producing plasmid from an O102-ST405 strain of Escherichia coli. As the ADI pathway was shown to be involved in the virulence of various Gram-positive bacteria, we tested whether the ADI pathway could be involved in the epidemiological success of...
Mechanisms of ResistanceTwo Hypervirulent Klebsiella pneumoniae Isolates Producing a blaKPC-2 Carbapenemase from a Canadian PatientThis report describes two hypervirulent Klebsiella pneumoniae isolates that produced K. pneumoniae carbapenemase (KPC), which were identified from a rectal swab and a urine culture upon hospital admission. The patient had recently traveled to Greece, where he was hospitalized.
