Degradation of organic mercury in high salt environments by a marine aerobic bacterium Alteromonas macleodii KD01

Dingxi Zhang; Bowei Chu; Qingqing Yang; Xiaoyan Zhang; Yingying Fang; Guangliang Liu; Lina Liang; Yingying Guo; Yongguang Yin; Yong Cai; Guibin Jiang

doi:10.1016/j.biortech.2024.130831

Degradation of organic mercury in high salt environments by a marine aerobic bacterium Alteromonas macleodii KD01

Bioresour Technol. 2024 May 10:402:130831. doi: 10.1016/j.biortech.2024.130831. Online ahead of print.

Authors

Dingxi Zhang¹, Bowei Chu¹, Qingqing Yang¹, Xiaoyan Zhang¹, Yingying Fang¹, Guangliang Liu², Lina Liang³, Yingying Guo⁴, Yongguang Yin⁵, Yong Cai⁶, Guibin Jiang⁷

Affiliations

¹ Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
² Institute of Environment and Health, Jianghan University, Wuhan 430056, China.
³ Beijing Zhongke PUYAN Science and Technology Co., Ltd, Beijing 100096, China.
⁴ Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Electronic address: yyguo@rcees.ac.cn.
⁵ Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China; Institute of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China.
⁶ Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Institute of Environment and Health, Jianghan University, Wuhan 430056, China.
⁷ State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.

PMID: 38734262
DOI: 10.1016/j.biortech.2024.130831

Abstract

Mercury (Hg), particularly organic mercury, poses a global concern due to its pronounced toxicity and bioaccumulation. Bioremediation of organic mercury in high-salt wastewater faces challenges due to the growth limitations imposed by elevated Cl^- and Na⁺ concentrations on microorganisms. In this study, an isolated marine bacterium Alteromonas macleodii KD01 was demonstrated to degrade methylmercury (MeHg) efficiently in seawater and then was applied to degrade organic mercury (MeHg, ethylmercury, and thimerosal) in simulated high-salt wastewater. Results showed that A. macleodii KD01 can rapidly degrade organic mercury (within 20 min) even at high concentrations (>10 ng/mL), volatilizing a portion of Hg from the wastewater. Further analysis revealed an increased transcription of organomercury lyase (merB) with rising organic mercury concentrations during the exposure process, suggesting the involvement of mer operon (merA and merB). These findings highlight A. macleodii KD01 as a promising candidate for addressing organic mercury pollution in high-salt wastewater.

Keywords: Halotolerant bacterium; High-salt wastewater; Organic mercury removal; mer operons.