GENOMIC CHARACTERIZATION OF ANTIMICROBIAL RESISTANCE DETERMINANTS IN PATHOGENIC BACTERIA

Abstract

The alarming occurrence and spread of antimicrobial resistance (AMR) among pathogenic bacteria is a major health concern across the world, which requires extensive genomic studies. This paper will seek to describe the genomic factors of antimicrobial resistance in pathogenic isolates of bacteria by determining genes of resistance, mutations of chromosomes, and related mobile genetic factors. Whole-genome sequencing (WGS) of bacterial isolates obtained on clinical sources was performed on high-throughput sequencing systems and then genome assembly and annotation were performed using common bioinformatics pipelines. The presence of antimicrobial resistance genes was determined by the tools and databases, such as ResFinder, the Comprehensive Antibiotic Resistance Database (CARD) and by other means, BLAST-based sequence analysis, whereas the presence of mobile genetic elements, e.g., plasmids, integrons, transposons, etc., was determined by the use of specialized genomic tools. The findings showed that there were various resistance determinants, such as 8-lactamase genes (bla family), methicillin resistance gene (mecA), and vancomycin resistance genes (vanA/vanB), which are evidence of wide-range multidrug resistance. Also, the discovery of various mobile genetic factors indicates that there is active horizontal gene transfer that helps in the spread of resistance. The phylogenetic analysis indicated the clustering of the isolates according to the genetic similarity and the resistance profile which allowed to have the information about evolutionary relation and the transmission route. Altogether, this paper indicates the usefulness of combining whole-genome sequencing with bioinformatics methodology in accurate characterization of antimicrobial resistance and the relevance of genomic surveillance in the proposed clinical decision-making and antimicrobial stewardship strategies.