bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2024, Номер unknown

Опубликована: Июль 9, 2024

Abstract Climate change poses significant risks to freshwater ecosystems, potentially exacerbating harmful cyanobacterial blooms and antibiotic resistance. We investigated these dual threats in Cosseys Reservoir, New Zealand, by simulating short-term warming scenarios assessing the role of oxidative stress. Microcosms were subjected Base (22°C), Normal (24°C), projected Future (27°C) temperatures, with additional treatments including reactive oxygen species (ROS). Metagenomic analysis revealed substantial restructuring microbial communities under conditions. Cyanobacterial abundance increased from 6.11% (initial) 20.53% at 24°C 10.66% 27°C. Notably, ROS addition mimicked effects temperature increase on proliferation. Toxin-producing families, Microcystaceae Nostocaceae , proliferated significantly. The microcystin synthesis gene ( mcy ) showed a strong positive association (R² = 0.88) abundance. Moreover, cyanobacteria exhibited enhanced nutrient acquisition pstS gene, R² 0.69) upregulated nitrogen metabolism pathways Concurrently, we observed marked resistance (ARG) rising temperatures. relative multidrug genes was consistently high across all conditions (50.82 % total ARGs). stress further intensified ARG proliferation, particularly for efflux pump e.g. acrB adeJ ceoB emrB MexK muxB ). Co-association network identified key antibiotic-resistant bacteria Streptococcus pneumoniae Acinetobacter baylyi ARGs rpoB2 bacA central dissemination This study demonstrates that even modest increases (2-5°C) can promote both ecosystems over short time scales. synergistic underscore complex challenges posed climate water quality public health. Highlights Short-term promotes toxic freshwater. Harmful their metabolic potential Reactive mimic exacerbate effects. Oxidative response strongly correlate networks identify host pathogen spread.

Язык: Английский