The Use of a Combined Bioinformatics Approach to Locate Antibiotic Resistance Genes on Plasmids From Whole Genome Sequences of Serovars From Humans in Ghana.

In the current study, we identified plasmids carrying antimicrobial resistance genes in draft whole genome sequences of 16 selected isolates representing six different serovars from humans in Ghana. The plasmids and the location of resistance genes in the genomes were predicted using a combination of PlasmidFinder, ResFinder, plasmidSPAdes and BLAST genomic analysis tools. Subsequently, S1-PFGE was employed for analysis of plasmid profiles. Whole genome sequencing confirmed the presence of antimicrobial resistance genes in isolates showing multidrug resistance phenotypically. ESBL, either or were present in two cephalosporin resistant isolates of . Virchow and . Poona, respectively. The systematic genome analysis revealed the presence of different plasmids in different serovars, with or without insertion of antimicrobial resistance genes. In . Enteritidis, resistance genes were carried predominantly on plasmids of IncN type, in . Typhimurium on plasmids of IncFII(S)/IncFIB(S)/IncQ1 type. In . Virchow and in . Poona, resistance genes were detected on plasmids of IncX1 and TrfA/IncHI2/IncHI2A type, respectively. The latter two plasmids were described for the first time in these serovars. The combination of genomic analytical tools allowed nearly full mapping of the resistance plasmids in all strains analyzed. The results suggest that the improved analytical approach used in the current study may be used to identify plasmids that are specifically associated with resistance phenotypes in whole genome sequences. Such knowledge would allow the development of rapid multidrug resistance tracking tools in populations using WGS.