Origin and Evolution of Antibiotic Resistance: The Common Mechanisms of Emergence and Spread in Water Bodies

Abstract

The environment, and especially freshwater, constitutes a reactor where the evolution and the rise of new resistances occur. In water bodies such as waste water effluents, lakes, and rivers or streams, bacteria from different sources, e.g., urban, industrial, and agricultural waste, probably selected by intensive antibiotic usage, are collected and mixed with environmental species. This may cause two effects on the development of antibiotic resistances: first, the contamination of water by antibiotics or other pollutants lead to the rise of resistances due to selection processes, for instance, of strains over-expressing broad range defensive mechanisms, such as efflux pumps. Second, since environmental species are provided with intrinsic antibiotic resistance mechanisms, the mixture with allochthonous species is likely to cause genetic exchange. In this context, the role of phages and integrons for the spread of resistance mechanisms appears significant. Allochthonous species could acquire new resistances from environmental donors and introduce the newly acquired resistance mechanisms into the clinics. This is illustrated by clinically relevant resistance mechanisms, such as the fluoroquinolones resistance genes qnr. Freshwater appears to play an important role in the emergence and in the spread of antibiotic resistances, highlighting the necessity for strategies of water quality improvement. We assume that further knowledge is needed to better understand the role of the environment as reservoir of antibiotic resistances and to elucidate the link between environmental pollution by anthropogenic pressures and emergence of antibiotic resistances. Only an integrated vision of these two aspects can provide elements to assess the risk of spread of antibiotic resistances via water bodies and suggest, in this context, solutions for this urgent health issue.

Integrons: Past, Present, and Future

“…In environments containing diverse resistance elements and diverse selective agents, plasmids can acquire genes for resistance to multiple antibiotics, disinfectants, and metals and at the same time assemble genes for degradative pathways capable of acting upon other xenobiotics (236). For these reasons, aquatic environments are regarded as a natural reactor for the generation of novel xenogenetic DNA elements (146,153,228,237).…”

“…They have readily spread by conjugation and natural transformation (145,146), such that they are now found in some 40 to 70% of Gram-negative pathogens from clinical contexts (147,148). They are common in the pathogens and commensal flora of livestock and companion animals (144,149,150).…”

Predation Efficacy of <i>Bdellovibrio bacteriovorus</i> on Multidrug-Resistant Clinical Pathogens and Their Corresponding Biofilms

“…The emergence and evolution of bacterial antibiotic resistance is one of the most significant threats to current public health and the economy (1). Increases in morbidity, length of hospitalization, healthcare cost, and mortality have been attributed to infections caused by multidrug-resistant (MDR) or extensive drug resistant (XDR) superbugs, which respond poorly to antimicrobial agents (2).…”

Low-Frequency Capacitive Sensing for Environmental Monitoring of Water Pollution with Residual Antibiotics

“…PCR detected Vancomycinresistant enterococci in wastewater and in drinking water and also detected methicillin-resistance staphylococci in hospital wastewater. In another instance, the spread of antibiotic resistance genes in wastewater treatment systems and their occurrence in surface and drinking water systems were revealed by quantitative PCR (qPCR) assay [15].…”