Biodegradation of plastics and pesticides by soil bacteria in Bangladesh: Insights into antibiotic resistance and potential therapeutic targets

Abstract

Soil bacteria exhibit varying degrees of tolerance to different concentrations of pesticides and plastics, and some possess the ability to degrade them, which is crucial for bioremediation. However, the multidrug-resistant properties of these bacteria pose challenges for their potential applications. Hence, this study aims to separate and characterize plastics and pesticide-degrading bacteria from non-contaminated and contaminated sites in Bangladesh and evaluate their antibiotic-resistant patterns to identify safety issues and discover promising therapeutic targets for combating multidrug-resistant infections. In the current study, a total of 90 soil samples were collected from different agricultural and dumped sites of Bangladesh, and bacterial isolates were screened for pesticides and plastics-degrading capabilities. Antibiotic sensitivity patterns of the potential isolates were evaluated using 16 different antibiotics. Biochemical, molecular, and genomic analyses were conducted to characterize the bacteria and identify antimicrobial resistance (AMR) genes. Our study screened out 122 plastic and 60 pesticide-tolerant bacterial isolates. Among them, 3 pesticide and 3 plastic-degrading isolates were found to be more promising and identified as Acinetobacter baumannii with pesticide-degrading capabilities from non-contaminated sites, and Klebsiella pneumoniae with plastic-degrading capabilities from contaminated sites. Antibiotic sensitivity test exhibited that most of the isolates were resistance to commonly used antimicrobials. The genomics and proteomics analysis uncovered the efflux pump-related genes responsible for the resistant mechanism and highlighted the involvement of genes that respond to antibiotics and transmembrane transport activities. Phylogenetic analysis confirmed the conservation of 2 common resistance genes adeF and gyrA, across diverse multidrug-resistant pathogens. Therefore, targeting conserved genes adeF and gyrA, to disrupt resistance mechanisms and combat persistent and clinically significant multidrug-resistant pathogens could be a promising strategy for developing combination therapies in medical science.