Characterization of ESBL disseminating plasmids

Abstract

Bacteria producing extended-spectrum β-lactamases (ESBLs) constitute a globally increasing problem that contributes to treatment complications and elevated death rates. The extremely successful dissemination by ESBL-producing Enterobacteriaceae during the latest decades is a result of the combination of mobilization, evolution and horizontal spread of β-lactamase genes on plasmids. In parallel, spread of these plasmids to particularly well-adapted bacterial clones (outbreak clones) has expanded. In this review we describe ESBL-producing bacteria and the genetic mechanisms for dissemination of ESBL resistance. We describe available methodology for studying plasmids and the importance of including plasmids in epidemiological typing as natural parts of the organisms. Plasmids play a fundamental role in how resistance arises and disseminates.

Prevalence and molecular characterization of extended-spectrum β-lactamase (ESBL) and plasmidic AmpC β-lactamase (pAmpC) producing <i>Escherichia coli</i> in dogs

“…Currently, there are different 172 CTX-M β-lactamases types (http://www.lahey.org/studies/), clustered into five phylogroups (CTX-M-1, -2, -8, -9 and -25). CTX-M-1 phylogroup, which includes CTX-M-15, is the most widely distributed all over the world [8]. …”

In-Vitro Study on Potential Efficacy of Acriflavine in the Prevention of Conjugational Transfer of Drug Resistance in Bacteria

“…In selection of donor strains, we focused on ESBL strains, as studies show that ESBL determining gene is usually plasmid borne, [19][20] and successful conjugation could easily be spotted by screening for transference of factors for resistance to Cefotaxime, Ceftazidime, etc. Our study too demonstrated the presence of ESBL genes on plasmids by successful conjugation in 2 out of 7 eligible donor ESBL Escherichia coli isolates ( Table 2).…”

Direct identification of antibiotic resistance genes on single plasmid molecules using CRISPR/Cas9 in combination with optical DNA mapping

“…With fast and robust diagnostics of resistance, adequate treatment could be administered directly, existing antibiotics could be used more efficiently and “last resort” antibiotics could be spared2. A key reason for the rapid spread of antibiotic resistance is horizontal transfer of resistance genes located on mobile genetic elements, such as plasmids3. Recently, plasmid-mediated resistance to last resort antibiotics, such as carbapenems4 and polymyxins5, have been reported.…”

“…These methods are now increasingly being replaced by next generation DNA sequencing approaches8, providing basepair resolution. Despite the improvement of sequencing techniques during the last decades, assembling plasmid sequences is not trivial due to their dynamic and repetitive nature which often requires time-consuming downstream bioinformatics analysis to obtain the complete picture3. Furthermore, whole genome sequencing is so far dependent on bacterial cultivation, DNA preparation, sequencing library preparation and long data collection procedures and is therefore slow, hampering its use in rapid diagnostics.…”

“…Furthermore, whole genome sequencing is so far dependent on bacterial cultivation, DNA preparation, sequencing library preparation and long data collection procedures and is therefore slow, hampering its use in rapid diagnostics. A comparison of different plasmid analysis methods can be found in a recent review3.…”