Electrode Colonization by the Feammox Bacterium Acidimicrobiaceae sp. Strain A6

Autor: Weitao Shuai, Melany Ruiz-Urigüen, Peter R. Jaffé
Rok vydání: 2018
Předmět:
0301 basic medicine
Acidimicrobiaceae sp. A6
Nitrogen
Iron
Microorganism
wetland soils
Heterotroph
iron reduction
Electron donor
010501 environmental sciences
ammonium oxidation
01 natural sciences
Applied Microbiology and Biotechnology
Actinobacteria
Soil
03 medical and health sciences
chemistry.chemical_compound
electrode-reducing bacteria
Ammonium Compounds
Environmental Microbiology
Ammonium
Anaerobiosis
Spotlight
Electrodes
Soil Microbiology
0105 earth and related environmental sciences
chemistry.chemical_classification
Bacteria
Ecology
biology
Chemistry
Microbiota
food and beverages
Heterotrophic Processes
Feammox
Electron acceptor
biology.organism_classification
Anoxic waters
030104 developmental biology
Wetlands
Environmental chemistry
anaerobic
lithoautotrophic
Oxidation-Reduction
Food Science
Biotechnology
Zdroj: Applied and Environmental Microbiology
ISSN: 1098-5336
0099-2240
DOI: 10.1128/aem.02029-18
Popis: Most studies on electrogenic microorganisms have focused on the most abundant heterotrophs, while other microorganisms also commonly present in electrode microbial communities, such as Actinobacteria strains, have been overlooked. The novel Acidimicrobiaceae sp. strain A6 (Actinobacteria) is an iron-reducing bacterium that can colonize the surface of anodes in sediments and is linked to electrical current production, making it an electrode-reducing bacterium. Furthermore, A6 can carry out anaerobic ammonium oxidation coupled to iron reduction. Therefore, findings from this study open the possibility of using electrodes instead of iron as electron acceptors, as a means to promote A6 to treat NH4+-containing wastewater more efficiently. Altogether, this study expands our knowledge of electrogenic bacteria and opens the possibility of developing Feammox-based technologies coupled to bioelectric systems for the treatment of NH4+ and other contaminants in anoxic systems.
Acidimicrobiaceae sp. strain A6 (A6), from the Actinobacteria phylum, was recently identified as a microorganism that can carry out anaerobic ammonium (NH4+) oxidation coupled to iron reduction, a process also known as Feammox. Being an iron-reducing bacterium, A6 was studied as a potential electrode-reducing bacterium that may transfer electrons extracellularly onto electrodes while gaining energy from NH4+ oxidation. Actinobacteria species have been overlooked as electrogenic bacteria, and the importance of lithoautotrophic iron reducers as electrode-reducing bacteria at anodes has not been addressed. By installing electrodes in the soil of a forested riparian wetland where A6 thrives, in soil columns in the laboratory, and in A6-bioaugmented constructed wetland (CW) mesocosms and by operating microbial electrolysis cells (MECs) with pure A6 culture, the characteristics and performances of this organism as an electrode-reducing bacterium candidate were investigated. In this study, we show that Acidimicrobiaceae sp. strain A6, a lithoautotrophic bacterium, is capable of colonizing electrodes under controlled conditions. In addition, A6 appears to be an electrode-reducing bacterium, since current production was boosted shortly after the CWs were seeded with enrichment A6 culture and current production was detected in MECs operated with pure A6, with the anode as the sole electron acceptor and NH4+ as the sole electron donor. IMPORTANCE Most studies on electrogenic microorganisms have focused on the most abundant heterotrophs, while other microorganisms also commonly present in electrode microbial communities, such as Actinobacteria strains, have been overlooked. The novel Acidimicrobiaceae sp. strain A6 (Actinobacteria) is an iron-reducing bacterium that can colonize the surface of anodes in sediments and is linked to electrical current production, making it an electrode-reducing bacterium. Furthermore, A6 can carry out anaerobic ammonium oxidation coupled to iron reduction. Therefore, findings from this study open the possibility of using electrodes instead of iron as electron acceptors, as a means to promote A6 to treat NH4+-containing wastewater more efficiently. Altogether, this study expands our knowledge of electrogenic bacteria and opens the possibility of developing Feammox-based technologies coupled to bioelectric systems for the treatment of NH4+ and other contaminants in anoxic systems.
Databáze: OpenAIRE