Liang, Y., L.J. Cook, and T.E. Mattes.
Environmental Science and Pollution Research 24(15):13760-13774(2017)

In a long-term field study, researchers tracked the abundance and activity of microbial VC degraders in three monitoring wells along a dilute VC plume at Naval Air Station Oceana. High-throughput sequencing of partial 16S rRNA genes and transcripts revealed diverse groundwater microbial communities and showed that methanotrophs and anaerobic respirers (e.g., methanogens, sulfate reducers, and iron reducers) were among the most active and abundant guilds. Quantitative PCR analysis showed that among bacterial guilds with a potential to contribute to VC biodegradation, methanotrophs were the most abundant and active microbial group. Ethene-oxidizing bacterial populations were less abundant and relatively inactive compared to methanotrophs. Expression of functional genes associated with both aerobic VC oxidation and anaerobic VC reduction was observed in one well. The groundwater community was found to contain diverse active bacterial guilds previously associated with metabolic and cometabolic VC degradation processes under either aerobic or anaerobic conditions that might have contributed to the slowly decreasing VC concentrations at the NAS Oceana site over the 6-year study period.