Maximal Greatness and Perfect Knowledge

Arbour, Benjamin H.

doi:10.5040/9780567681317.ch-009

Cited by 1 publication

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It was also reported for its potential to degrade diesel derived hydrocarbons in a microbial fuel cell. Desulfovibrio directly transferred extracellular electrons to the anode through a multihemic cytochrome c protein in a mediator-free microbial fuel cell. − In another study, Desulfovibrio was reported to produce nanoscale, bacterial appendages for direct extracellular electron transfer Desulfovibrio was also able to indirectly transfer electrons to the electrode using an inorganic electron mediator in a microbial fuel cell. , …”

Section: Resultsmentioning

confidence: 99%

Evidence and Mechanisms of Selenate Reduction to Extracellular Elemental Selenium Nanoparticles on the Biocathode

Zhang

Asefaw

Xiong

et al. 2022

Environ. Sci. Technol.

View full text Add to dashboard Cite

Intracellular selenium nanoparticles (SeNPs) production is a roadblock to the recovery of selenium from biological water treatment processes because it is energy intensive to break microbial cells and then separate SeNPs. This study provided evidence of significantly more extracellular SeNP production on the biocathode (97−99%) compared to the conventional reactors (1−90%) using transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy. The cathodic microbial community analysis showed that relative abundance of Azospira oryzae, Desulfovibrio, Stenotrophomonas, and Rhodocyclaceae was <1% in the inoculum but enriched to 10−21% for each group when the bioelectrochemical reactor reached a steady state. These four groups of microorganisms simultaneously produce intracellular and extracellular SeNPs in conventional biofilm reactors per literature review but prefer to produce extracellular SeNPs on the cathode. This observation may be explained by the cellular energetics: by producing extracellular SeNPs on the biocathode, microbes do not need to transfer selenate and the electrons from the cathode into the cells, thereby saving energy. Extracellular SeNP production on the biocathode is feasible since we found high concentrations of C-type cytochrome, which is well known for its ability to transfer electrons from electrodes to microbial cells and reduce selenate to SeNPs on the cell membrane.

show abstract