Insight into antibiotic and heavy metal resistance gene diversity in two ecologically important rivers of Bangladesh: a metagenomics analysis
摘要
The worldwide increase in antimicrobial resistance (AMR) presents a significant danger to public health, with aquatic ecosystems being identified as essential reservoirs for antibiotic resistance genes (ARGs). In Bangladesh, the convergence of high population density, inadequate sanitary infrastructure, and widespread antibiotic usage significantly enhances the potential for disseminating AMR via river systems, where heavy metal contamination further exacerbates this risk.
MethodsThis study used shotgun metagenomic sequencing to thoroughly characterize the resistome of two branch rivers, Bongshai and Kumar, originating from the major rivers the Jamuna and the Padma. This work is the first investigation to comprehensively analyze the prevalence and variety of ARGs alongside genes conferring resistance to heavy metals (e.g., mercury, arsenic, and lead) in these ecologically and socioeconomically crucial aquatic environments.
ResultsOur data indicate significant disparities in the resistome composition between the two locations, underscoring unique environmental and human influences. The Bongshai river exhibited a markedly abundant and diversified resistome along with metal-resistome, encompassing resistance classes linked to last-resort antibiotics (carbapenems, colistin, fluoroquinolones, aminoglycosides, cephalosporins, β-lactams, and metal-binding proteins). This river is linked with several upstream rivers running through industrial and densely populated locations. Conversely, the Kumar river site displayed a more restricted resistome, dominated by tetracycline, fluoroquinolone, sulfonamide resistance, and a lower abundance of metal-resistance determinants. Identifying multidrug-resistant (MDR) factors and metal-resistance genes highlights the considerable health hazards of contaminated river systems.
ConclusionThis work offers critical insights into the environmental spread of ARGs and metal-resistance genes in river ecosystems, emphasizing the necessity for continuous monitoring, targeted mitigation strategies, and integrated policies to curb AMR transmission and safeguard public health in Bangladesh.