Review Article
Nayyar N and Lal R
Abstract
Recent revelation of the evolution of Hexachlorocyclohexane (HCH) degrading sphingomonads and their acquisition of lin genes for the degradation of HCH isomers at the HCH dumpsites and HCH contaminated sites has lead us to consider that bacteria employ science and chemistry beyond scientific imagination. The HCH contamination of the environment portrays one of the best examples to highlight the evolution of catabolic genes and pathways leading to survival of these bacteria at HCH concentrations as high as 450 mg/g soil. While contamination of the environment with HCH has created several health related issues, this compound has not only enabled us to study the marvel of HCH degradation that sphingomonads employ but has also emerged as a good model to study the evolution of catabolic genes, especially the lin genes. The potential of HCH degradation by these sphingomonads can be tapped in order to create a phenomenal and large scale bioremediation technology. This review describes briefly the massive contamination of our environment by HCH isomers, along with the spontaneous evolution of the versatile HCH degradation pathways in sphingomonads and lin genes in response to HCH.