Bacillus coagulans XY2 ameliorates copper-induced toxicity by bioadsorption, gut microbiota and lipid metabolism regulation

Excessive copper pollutes the environment and endangers human health, attracting plenty of global attention. In this study, a novel strain named Bacillus coagulans XY2 was discovered to have a great copper tolerance and adsorption capacity. B. coagulans XY2 might maintain copper homeostasis through multisystem synergies of copper resistance, sulfur metabolism, Fe-S cluster assembly, and siderophore transport. In mice, by promoting the expression of SREBF-1 and SREBF-2 and their downstream genes, B. coagulans XY2 significantly inhibited the copper-induced decrease in weight growth rate, ameliorated dyslipidemia, restored total cholesterol and tri-glyceride contents both in serum and liver. Furthermore, B. coagulans XY2 recovered the diversity of gut microbiota and suppressed the copper-induced reduction in the ratio of Firmicutes to Bacteroidota. Serum metabolomics analysis showed that the alleviating effect of B. coagulans XY2 on copper toxicity was mainly related to lipid metabolism. For the first time, we demonstrated mechanisms of copper toxicity mitigation by B. coagulans XY2, which was related to self-adsorption, host copper excretion promotion, and lipid metabolism regulation. Moreover, working model of B. coagulans XY2 on copper homeostasis was predicted by whole-genome analysis. Our study provides a new solution for harmfulness caused by copper both in human health and the environment.

Automated summary

In this study, a novel strain called Bacillus coagulans XY2 was found to have high copper tolerance and adsorption capacity. It was able to maintain copper homeostasis through multiple system synergies. Through experiments on mice, it was shown that B. coagulans XY2 could significantly alleviate the negative effects of copper, such as weight growth decrease and dyslipidemia, by affecting gene expression and restoring lipid metabolism. This research provides new insights into the mechanisms of copper toxicity mitigation and offers a potential solution for the harmful effects of copper on human health and the environment.