Effects of marine heatwaves on the dynamics of marine coastal microbial communities

The shift toward lysogeny observed under elevated temperatures may enhance horizontal gene transfer, accelerating the spread of virulence and antibiotic resistance genes. In fact, we observed an increased abundance of these genes in samples under heat stress. These processes could weaken ecosystem resilience, disrupt microbial-driven biogeochemical cycles, and amplify risks to marine and human health. Our study underscores the need to integrate microbial and viral responses into predictions of ocean functioning in a rapidly warming world.