Abstract
Irrigation water is well known as potential source of pathogens in fresh produce. However, its role in transferring antibiotic resistance determinants is less well investigated. Therefore, we analyzed the contribution of surface and tap water to the resistome of overhead-irrigated chive plants. Field-grown chive was irrigated with either surface water (R-system) or tap water (D-system), from planting to harvest. Water along the two irrigation chains as well as the respective plants were repeatedly sampled and screened for 264 antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs), using high-capacity qPCR. Differentially abundant (DA) ARGs were determined by comparing the two systems. On R-chive, β-lactam ARGs, multidrug-resistance (MDR) determinants, and MGEs were most abundant, while D-chive featured DA ARGs from the vancomycin class. Diversity and number of DA ARGs was the highest on young chives, strongly diminished at harvest, and increased again at the end of shelf life. Most ARGs highly enriched on R- compared to D-chive were also enriched in R- compared to D-sprinkler water, indicating that water played a major role in ARG enrichment. Of note, blaKPC was detected at high levels in surface water and chive. We conclude that water quality significantly affects the resistome of the irrigated produce.
Highlights
After their discovery in the 1920s, antibiotics started revolutionizing medicine and have since saved millions of lives
To compare antibiotic resistance genes (ARGs) abundance between chive plants irrigated with either open-top reservoir water (R-chive) or sterile filtered tap water (D-chive), fold changes were calculated using D-chive as a reference
We had shown previously that irrigation water quality had a significant impact on the overall detected antibiotic-resistant bacteria in the model system chive irrigated overhead with either sterile filtered tap water or surface water pumped from an opentop reservoir [26]
Summary
After their discovery in the 1920s, antibiotics started revolutionizing medicine and have since saved millions of lives. Antibiotic resistance has been identified within 5 to 10 years after introduction of a new antibiotic, but in some cases, even before the antibiotic’s broad clinical application [1]. The development and acquisition of antibiotic resistance in bacteria is a natural defense mechanism. This is why antibiotic-resistant bacteria (ARB) and genes conferring antibiotic resistance (ARGs) have been detected even in environments completely lacking anthropogenic influence, such as permafrost sediments [2]. The broad application of antibiotics in clinics as well as animal husbandry has promoted the transfer of environmental ARGs into pathogenic bacteria, resulting in many new multidrug-resistant (MDR) pathogens, for some of which only few, if any, last resort antibiotics have remained as treatment options [3]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
