Bacterial genetic analysis

In this study, the combined effects of increasing Cr(VI) concentration and antibiotics on the antibiotic resistance genes (ARGs) of Bacillus cereus SH-1 were investigated through experiments. As the chromium concentration increased, it triggered ROS oxidative stress in SH-1, increased antioxidant enzyme activity, and enhanced plasmid conjugative transfer. However, at the same time, the removal rate of Cr(VI) by SH-1 decreased to below 80%. The antibiotic resistance also changed under these conditions, with the MICs of TET and AMC showing a positive correlation with Cr(VI) induction, while AZM and CL showed a negative correlation. Overexpression of seven genes of the HAE-1 family efflux pumps was detected through metagenomics and proteomics. Additionally, the study also found that co-contamination of Cr(VI) and antibiotics leads to the emergence and spread of resistant bacteria, posing a threat to human health and the environment.