Dehalococcoides-assisted reductive dechlorination of xenobiotics and recalcitrant compounds

Xenobiotics are synthetic chemicals used for domestic, agricultural and industrial purposes which are not intrinsically part of the metabolic process of an organism. Chlorinated xenobiotics are highly dangerous and harmful to human and the environment, hence, their removal from any system is of utmost importance and the need of the hour. Bioremediation, a buzzword for this century, reduces the time and money spent on the removal of hazardous compounds. Bioremediation involving biostimulation and bioaugmentation has emerged as the most advantageous, economically and environmentally viable soil and water decontamination and detoxification techniques. Several bacteria are reported to transform or altogether remove chlorinated xenobiotics from the sites of contamination. Most prominent among them is Dehalococcoides, which selectively dehalogenates the chlorinated compounds and converts them into less lethal substances like ethene. This review gives a detailed description of bioremediation strategies for reductive dechlorination of xenobiotics and recalcitrants by the application of Dehalococcoides, with a major emphasis on environmental biotechnology research that requires immediate attention to avoid widespread groundwater contamination due to halogenated organic compounds.