Prevalence and Diversity of Antibiotic Resistant Escherichia coli From Anthropogenic-Impacted Larut River

Abstract

Aquatic environments, under frequent anthropogenic pressure, could serve as reservoirs that provide an ideal condition for the acquisition and dissemination of antibiotic resistance genetic determinants. We investigated the prevalence and diversity of antibiotic-resistantEscherichia coliby focusing on their genetic diversity, virulence, and resistance genes in anthropogenic-impacted Larut River. The abundance ofE. coliranged from (estimated count) Est 1 to 4.7 × 105(colony-forming units per 100 ml) CFU 100 ml−1to Est 1 to 4.1 × 105CFU 100 ml−1with phylogenetic group B1 (46.72%), and A (34.39%) being the most predominant. The prevalence of multiple antibiotic resistance phenotypes ofE. coli, with the presence oftetandsulresistance genes, was higher in wastewater effluents than in the river waters. These findings suggested thatE. colicould be an important carrier of the resistance genes in freshwater river environments. The phylogenetic composition ofE. coliand resistance genes was associated with physicochemical properties and antibiotic residues. These findings indicated that the anthropogenic inputs exerted an effect on theE. coliphylogroup composition, diversification of multiple antibiotic resistance phenotypes, and the distribution of resistance genes in the Larut River.