Evidence of competition between electrogens shaping electroactive microbial communities in microbial electrolysis cells
Journal article, 2022

In single-chamber microbial electrolysis cells (MECs), organic compounds are oxidized at the anode, liberating electrons that are used for hydrogen evolution at the cathode. Microbial communities on the anode and cathode surfaces and in the bulk liquid determine the function of the MEC. The communities are complex, and their assembly processes are poorly understood. We investigated MEC performance and community composition in nine MECs with a carbon cloth anode and a cathode of carbon nanoparticles, titanium, or stainless steel. Differences in lag time during the startup of replicate MECs suggested that the initial colonization by electrogenic bacteria was stochastic. A network analysis revealed negative correlations between different putatively electrogenic Deltaproteobacteria on the anode. Proximity to the conductive anode surface is important for electrogens, so the competition for space could explain the observed negative correlations. The cathode communities were dominated by hydrogen-utilizing taxa such as Methanobacterium and had a much lower proportion of negative correlations than the anodes. This could be explained by the diffusion of hydrogen throughout the cathode biofilms, reducing the need to compete for space.

bioanode

biocathode

bioelectrochemical system (BES)

microbial electrolysis cells (MECs)

microbial community assembly

Author

Marie Abadikhah

Chalmers, Architecture and Civil Engineering, Water Environment Technology

Miguel de Celis Rodriguez

Complutense University

Frank Persson

Chalmers, Architecture and Civil Engineering, Water Environment Technology

Britt-Marie Wilen

Chalmers, Architecture and Civil Engineering, Water Environment Technology

Anne Farewell

University of Gothenburg

Oskar Modin

Chalmers, Architecture and Civil Engineering, Water Environment Technology

Frontiers in Microbiology

1664302x (eISSN)

Vol. 13 959211

Controlling the function of bioelectrochemical systems in Wastwater treatment processes

J. Gust. Richert stiftelse (2022-00757), 2022-08-01 -- 2024-05-30.

Bioelectrochemical systems for sustainable wastewater management

Formas (2018-00622), 2019-01-01 -- 2021-12-31.

Subject Categories

Inorganic Chemistry

Biochemistry and Molecular Biology

Ecology

Other Chemical Engineering

Microbiology

DOI

10.3389/fmicb.2022.959211

PubMed

36590422

More information

Latest update

1/29/2024