Simultaneous regulation of biocathodic γ-HCH dechlorination and CH4 production by tailoring the structure and function of biofilms based on quorum sensing

Jie Cheng; Xin Su; Meng Liu; Zhijiang Lu; Jianming Xu; Yan He

doi:10.1016/j.envpol.2023.122357

Simultaneous regulation of biocathodic γ-HCH dechlorination and CH₄ production by tailoring the structure and function of biofilms based on quorum sensing

Environ Pollut. 2023 Oct 15:335:122357. doi: 10.1016/j.envpol.2023.122357. Epub 2023 Aug 9.

Authors

Jie Cheng¹, Xin Su², Meng Liu³, Zhijiang Lu⁴, Jianming Xu⁵, Yan He⁶

Affiliations

¹ Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China. Electronic address: chengjie9605@zju.edu.cn.
² Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China. Electronic address: xsu37@zju.edu.cn.
³ Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China. Electronic address: 12014063@zju.edu.cn.
⁴ Department of Environmental Science and Geology, Wayne State University, Detroit, MI, 48201, United States. Electronic address: jlu@wayne.edu.
⁵ Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China. Electronic address: jmxu@zju.edu.cn.
⁶ Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China; Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, Hangzhou, 310058, China. Electronic address: yhe2006@zju.edu.cn.

PMID: 37567403
DOI: 10.1016/j.envpol.2023.122357

Abstract

Dechlorination of chlorinated organic pollutants and methanogenesis are attractive biocathode reductions in microbial electrolysis cells (MECs). Quorum sensing (QS) is applied to regulate microbial communications. However, how acyl-homoserine lactones (AHLs)-dependent QS organize the assembly of the biocathode microbial community, and then regulate multiple biocathode reductions remains unclear. By applying N-butanoyl homoserine lactone (C4-HSL), N-hexanoyl homoserine lactone (C6-HSL) and 3-oxo-hexanoyl homoserine lactone (3OC6-HSL) in γ-hexachlorocyclohexane (γ-HCH) contaminated MECs, this study investigated the changes of biofilm microbial structure and function and the mechanisms of AHLs-QS on γ-HCH dechlorination and CH₄ production. Exogenous C4-HSL and 3OC6-HSL increased cytochrome c production and enriched dechlorinators, electroactive bacteria but not methanogens to accelerate γ-HCH dechlorination and inhibit CH₄ production. C6-HSL facilitated dechlorination and CH₄ production by enhancing biofilm electroactivity and increasing membrane transportation. Besides, exogenous C6-HSL restored the electron transfer capacity that was damaged by the concurrent addition of acylase, an endogenous AHL quencher. From the perspective of microbial assembly, this study sheds insights into and provides an efficient strategy to selectively accelerate dechlorination and CH₄ production by harnessing microbial structure based on QS systems to meet various environmental demands.

Keywords: Acyl-homoserine lactones dependent quorum sensing; CH(4); Cathode biofilm; Function; γ-hexachlorocyclohexane.

MeSH terms

4-Butyrolactone
Acyl-Butyrolactones
Biofilms
Hexachlorocyclohexane*
Quorum Sensing*

Substances

homoserine lactone
Hexachlorocyclohexane
N-butyrylhomoserine lactone
4-Butyrolactone
Acyl-Butyrolactones