Intestinal Methylation and Demethylation of Mercury

  • Hong Li
  • Xiaoying Lin
  • Jiating Zhao
  • Liwei Cui
  • Liming Wang
  • Yuxi Gao
  • Bai Li
  • Chunying Chen
  • Yu-Feng LiEmail author
Focused Review


Mercury (Hg) is a global pollutant, which is linked with different diseases. The methylation of Hg and demethylation of methylmercury (MeHg) in the environment were extensively studied and summarized; however, the transformation of Hg in the intestine is less presented. In this review, the research progress and the perspectives on the intestinal transformation of Hg were discussed. Studies found that MeHg could be formed when exposed to inorganic Hg by the gut microbiota in aquatic organisms, terrestrial invertebrates, and mammals, etc. hgcAB genes could be used as indicators for predicting Hg methylation potential. In vitro studies using fecal specimen, intestinal contents, and the isolated intestinal microbes confirmed the intestinal demethylation of MeHg. The investigation on the effects of Hg exposure to the abundance and diversity of intestinal microbes and their metabolites could shed light on the mechanism of the toxicity of Hg, especially the neurotoxicity of MeHg, which deserves further study.


Mercury Intestinal microbes Methylation Demethylation 



Fundings were provided by National Natural Science Foundation of China with Grant No. 11475196 and Ministry of Science and Technology of the People's Republic of China with Grant No. 2016YFA0201600.


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Authors and Affiliations

  1. 1.CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, HKU-IHEP Joint Laboratory on Metallomics, Institute of High Energy PhysicsChinese Academy of SciencesBeijingChina
  2. 2.University of Chinese Academy of SciencesBeijingChina
  3. 3.CAS Key Laboratory for Biological Effects of Nanomaterials and NanosafetyNational Center for Nanoscience and TechnologyBeijingChina

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