Relative abundance of ‘Candidatus Tenderia electrophaga’ is linked to cathodic current in an aerobic biocathode community

Abstract

Biocathode microbial communities are proposed to catalyse a range of useful reactions. Unlike bioanodes, model biocathode organisms have not yet been successfully cultivated in isolation highlighting the need for culture‐independent approaches to characterization. Biocathode MCL (Marinobacter, Chromatiaceae, Labrenzia) is a microbial community proposed to couple CO2 fixation to extracellular electron transfer and O2 reduction. Previous metagenomic analysis of a single MCL bioelectrochemical system (BES) resulted in resolution of 16 bin genomes. To further resolve bin genomes and compare community composition across replicate MCL BES, we performed shotgun metagenomic and 16S rRNA gene (16S) sequencing at steady‐state current. Clustering pooled reads from replicate BES increased the number of resolved bin genomes to 20, over half of which were > 90% complete. Direct comparison of unassembled metagenomic reads and 16S operational taxonomic units (OTUs) predicted higher community diversity than the assembled/clustered metagenome and the predicted relative abundances did not match. However, when 16S OTUs were mapped to bin genomes and genome abundance was scaled by 16S gene copy number, estimated relative abundance was more similar to metagenomic analysis. The relative abundance of the bin genome representing ‘Ca. Tenderia electrophaga’ was correlated with increasing current, further supporting the hypothesis that this organism is the electroautotroph.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jul 11, 2017
Source ID
10.1111/1751-7915.12757

Entities

People

  • Anthony P. Malanoski
  • Baochuan Lin
  • Brian J Eddie
  • Sarah M. Glaven
  • W. Judson Hervey Iv
  • Zheng Wang

Organizations

  • Defense Threat Reduction Agency
  • Office of Naval Research
  • United States Naval Research Laboratory

Tags

Fields of Study

  • Biology
  • Environmental science

Readers

  • Microbial Pathology
  • Molecular Genetics

Technology Areas

  • Biotechnology
  • Microelectronics