Escherichia coli O157:H7 Genome sequencing. Escherichia coli O157:H7

Anthropogenic greenhouse gases (GHG) pose a great threat to both ecosystems and public health. This study investigated how acid rain, a major consequence of GHG emissions, affects the survival and evolution of the pathogen Escherichia coli O157:H7 in soil. In a 150-day soil microcosm experiment, we exposed soil inoculated with E. coli O157:H7 to normal or acid rain. Despite a general decline in E. coli abundance post-invasion, acid rain led to higher survival rates compared to normal rain. Acid rain created opportunities for the invasion of alien bacteria by promoting microbial competition and inducing disorder. Simultaneously, acid rain accelerated the evolution of E. coli with evolved strains showing enhanced biofilm formation and increased stress resistance. The evolved strain had an 8-fold greater transmission risk in lettuce and a 5-fold greater lethality in mice than its ancestor. These results emphasized the need for acid rain mitigate strategies to protect public health.