Profiles of antibiotic resistome risk in diverse water environments

The water environment is considered to be a reservoir for antibiotic resistant bacteria and antibiotic resistance genes. However, profiles of antibiotic resistome risk in different water environments remain largely underexplored. Here we found that the number, abundance and risk of antibiotic resistance genes in wastewater, especially slaughterhouse wastewater, were higher than those in natural water. Then, 6167 high-quality metagenome-assembled genomes were obtained. The main hosts were Escherichia, Desulfobacter, Citrobacter and Pseudomonas_E, respectively. Moreover, distinct of patterns of horizontal gene transfer were observed in different microbes. Overall, microbial composition and resistance risk varied in different water environments and there was a correlation between microbial composition and resistome risk. Therefore, models based on microbial composition were constructed with an accuracy of 86.87 ± 1.18% for predicting the risk of resistance in unknown water environments, providing an essential reference for dealing with antibiotic-resistant pollution and for water management. Wastewater, especially from slaughterhouses, carries higher levels of antibiotic-resistant genes than natural water, with hosts including Escherichia, Desulfobacter, Citrobacter, and Pseudomonas_E, according to metagenomic analysis of water samples from China.