Project description:The study aimed to characterize plasmids mediating carbepenem resistance in Klebsiella pneumoniae in Pretoria, South Africa. We analysed 56 K. pneumoniae isolates collected from academic hospital around Pretoria. Based on phenotypic and molecular results of these isolates, 6 representative isolates were chosen for further analysis using long reads sequencing platform. We observed multidrug resistant phenotype in all these isolates, including resistance to aminoglycosides, tetracycline, phenicol, fosfomycin, floroquinolones, and beta-lactams antibiotics. The blaOXA-48/181 and blaNDM-1/7 were manily the plasmid-mediated carbapenemases responsible for carbapenem resistance in the K. pneumoniae isolates in these academic hospitals. These carbapenemase genes were mainly associated with plasmid replicon groups IncF, IncL/M, IncA/C, and IncX3. This study showed plasmid-mediated carbapenemase spread of blaOXA and blaNDM genes mediated by conjugative plasmids in Pretoria hospitals.
Project description:Genetic surrounding of blaNDM-1, blaNDM-3 and blaNDM-6 and conjugation frequency of blaNDM-1-carrying plasmids in Enterobacteriaceae
Project description:We developed a multi recombinase engineering rationale, that combines oligonucleotide recombineering with the selective capacity of antibiotic resistance via transient insertion of selector plasmids. We tested this method in Mycoplasma pneumoniae, a bacterium with a very inefficient native recombination machinery. A wide variety of targeted genome modifications were carried out. We did whole genome sequencing of some clones to confirm that the engineering method is not mutagenic and ensure that genome modifications only occurred at the intended loci. Specifically we sequenced clones carrying 1 kb deletion at 4 different chromosomal locations (i.e., M129-GP35-PtetCre Δ1kbmpn088::lox scar, M129-GP35-PtetCre Δ1kbmpn256::lox scar, M129-GP35-PtetCre Δ1kbmpn440::lox scar, M129-GP35-PtetCre Δ1kbmpn583::lox scar), a clone carrying a 30 kb deletion (M129-GP35-PtetCre Δ30kbNE region::pLoxPuro) and a clone carrying a 5.5 kb deletion that was complemented with the two essential genes found in this area (M129-GP35 Δ5.5kbmpn633-mpn638::mpn636-637lox scar)
Project description:Phylogeny, resistome, virulome and organizational structure of plasmids containing blaKPC-2 or blaNDM-1 of carbapenemase-producing Klebsiella pneumoniae from transplanted patients
