Methanotrophic Bacteria: Use in Bioremediation

TLDR: The methanotrophic bacteria that oxidize methane as an energy source and carbon source through the enzyme methane monooxygenase (MMO) can cometabolize or transform nongrowth substrates by either growing or resting cells as discussed by the authors.

Abstract: The methanotrophs are aerobic bacteria that oxidize methane as an energy source and carbon source through the enzyme methane monooxygenase (MMO). This MMO can cometabolize or transform nongrowth substrates by either growing or resting cells. Cometabolism is a result of nonspecific MMO activity towards organic compounds that do not serve as carbon or energy sources. While many cometabolizing bacterial species have been identified, the best studied are the methanotrophs. The reason for this is that methanotrophs are ubiquitous and can cometabolize many aliphatic compounds, alkanes, and aromatic compounds. Methanotrophs have been intensely studied for use in degrading chlorinated solvents, most notably trichloroethylene, to environmentally acceptable concentrations in soils, sediment, and groundwater. Stimulation of methanotrophic bacteria is accomplished through the addition of methane and other gaseous nutrients resulting in an increase in contaminant biodegradation and biotransformation. The composition of gaseous nutrients used with methane is dependent on the characteristics of the site geochemistry and microbiology. This biostimulation may be applied in situ within the contaminated aquifer or soil. If necessary, the contaminated soil or groundwater can be moved and treated ex situ based on the site-specific needs.