Wetland sediments host diverse microbial taxa capable of cycling alcohols.

Wetland sediments host diverse microbial taxa capable of cycling alcohols. Appl Environ Microbiol. 2019 Apr 12;: Authors: Dalcin Martins P, Frank J, Mitchell H, Markillie LM, Wilkins MJ Abstract Alcohols are commonly derived from the degradation of organic matter, and yet are rarely measured in environmental samples. Wetlands in the Prairie Pothole Region (PPR) support extremely high methane emissions and the highest sulfate reduction rates reported to date, likely contributing to a significant proportion of organic matter mineralization in this system. While ethanol and isopropanol concentrations up to 4-5 mM in PPR wetland pore fluids have been implicated in sustaining these high rates of microbial activity, the mechanisms that support alcohol cycling in this ecosystem are poorly understood. Here we leveraged metagenomic and transcriptomic tools to identify genes, pathways and microorganisms potentially accounting for alcohol cycling in PPR wetlands. Phylogenetic analyses revealed diverse alcohol dehydrogenases and putative substrates. Alcohol dehydrogenase and aldehyde dehydrogenase genes were encoded in 62 metagenome-assembled genomes (MAGs) affiliated to 16 phyla. The most frequently encoded pathway (in 30 MAGs) potentially accounting for alcohol production was a Pyrococcus furiosus-like fermentation which can involve pyruvate:ferredoxin oxidoreductase (PFOR). Transcripts for 93 out of 137 PFOR genes encoded in these MAGs were d...
Source: Applied and Environmental Microbiology - Category: Microbiology Authors: Tags: Appl Environ Microbiol Source Type: research