Facilitation of conjugative DNA transfer in zooplankton: Insights from Moina macrocopa and Escherichia coli
Year: 2025
Type: article
Abstract: Zooplankton are vital to aquatic ecosystems and the aquaculture industry. The microbiome within zooplankton plays a crucial role in their growth, fecundity, and stress tolerance. Conjugative DNA transfer can alter the microbiome population, driving microbial evolution, spreading antibiotic resistance, and serving as a tool for microbiome modulation. A previous study found that antibiotic resistance genes can be conjugatively transferred between Enterococcus bacteria in the freshwater zooplankton Daphnia . However, it is unclear whether this phenomenon occurs in other zooplankton species and bacteria, and to what extent zooplankton facilitate conjugative transfer. In this study, we investigated the conjugative transfer of a plasmid belonging to the IncP incompatibility group within the zooplankton Moina macrocopa , a species relevant to aquaculture. We used colony counting and flow cytometry to detect conjugative transfer. Our results indicate that the presence of M. macrocopa increases conjugation efficiency between Escherichia coli by at least five orders of magnitude. In situ conjugative transfer in live M.macrocopa from E. coli to native M. macrocopa -associated microbes, predominantly Flavobacterium and Limnohabitans , was not detected. Following incubation of M. macrocopa carcasses on nutrient-rich agar, Aeromonas became a dominant genus. In this environment, ex situ conjugation from E. coli to M. macrocopa- associated microbes was observed. We isolated transconjugants from the genera Aeromonas and Vogesella , which were able to efficiently transfer the plasmid back to E. coli . These findings have significant implications for understanding the impact of conjugative transfer and the spread of antibiotic resistance in aquatic environments.
Source: Heliyon
Institutions: Naresuan University, Prince of Songkla University
Language: English
Subfield: Pollution
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,270
OpenAlex ID: W4416386773