An exciting new discovery of a bacterial genus in a fracking well has been made by microbiologists at Ohio state university. The full name is Candidatus Frackibacter and was discovered using genomic analysis of two separate hydraulic fracturing wells. In biological nomenclature, "Candidatus" indicates that the organism has been identified using genomic approaches and the "Frackibacter" is a play on the word "fracking" which is the short form hydraulic fracturing.
Fracking is a process by which shale is fractured in order to liberate natural oil and gas. High pressure mixture of water, sand and other chemicals are pumped into shale shale formations in order to open small fissures that will allow oil and gas to be recovered. It is quite controversial as it can cause serious environmental issues such as earth tremors, wasting water and leaking toxic chemcials into the environment.
Despite this, scientists at Ohio state believe that Candidatus Frackibacter could be unique to fracking wells as they are thought to metabolise some of the chemcials that are used in the fracking process.
What a testament to how quickly bacteria are able adapt and evolve to new environments!
Microbial metabolisms in a 2.5-km-deep ecosystem created by hydraulic fracturing in shales
Shale gas accounts for one-third of natural gas energy resources worldwide. It has been estimated that shale gas will provide half of the natural gas in the USA, annually, by 2040, with the Marcellus shale in the Appalachian Basin projected to produce three times more than any other formation1. Recovery of these hydrocarbons is dependent on hydraulic fracturing technologies, where the high-pressure injection of water and chemical additives generates extensive fractures in the shale matrix. Hydrocarbons trapped in tiny pore spaces are subsequently released and collected at the wellpad surface, together with a portion of the injected fluids that have reacted with the shale formation. The mixture of injected fluids and hydrocarbons collected is referred to as ‘produced fluids’.
Microbial metabolism and growth in hydrocarbon reservoirs has both positive and negative impacts on energy recovery. Whereas stimulation of methanogens in coal beds enhances energy recovery2, bacterial hydrogen sulfide production (‘reservoir souring’) decreases profits and contributes to corrosion and the risk of environmental contamination3. Additionally, biomass accumulation within newly generated fractures may reduce their permeability, decreasing natural gas recovery. Despite these potential microbial impacts, little is known about the function and activity of microorganisms in hydraulically fractured shale.
Initial work by our group and others4,5,6,7,8,9 used single marker gene analyses to identify microorganisms from several geographically distinct shale formations. These analyses showed similar halotolerant taxa in produced fluids several months after hydraulic fracturing. To assign functional roles to these organisms, we conducted metagenomic and metabolite analyses on input and produced fluids up to a year after hydraulic fracturing (HF) from two Appalachian basin shales, the Marcellus and Utica/Point Pleasant (Utica) formations. Although an earlier metagenomic study examined shale-produced fluids10, the microbial communities were only sampled for nine days after HF. Here, we have reconstructed the first genomes from fractured shale, examining the microbial metabolisms sustained in these engineered, deep subsurface habitats over a period of 328 days. We provide evidence for metabolic interdependencies, and describe chemical and viral factors that control life in these economically important ecosystems. Our results show microbial degradation of chemical additives, the potential for microbially induced corrosion and the formation of biogenic methane, all of which have implications for the sustainability of energy extraction.