Isolated from the River Elbe in Germany, Sphingomonas wittichii RW 1 belongs to a family of bacteria that play a role in breaking down complex aromatic compounds associated with decaying plant mater and chemical pollution. S. wittichii itself is capable of completely breaking down toxic dioxin pollutants, and was selected for sequencing by the DOE JGI because of its potential application as a cost-effective means of bioremediation.
|Scanning electron micrograph of F. succinogenes during crystalline cellulose degradation. (Image courtesy of David Colquhoun.)
Dioxins are part of what the World Health Organization has termed “the dirty dozen” – persistent organic pollutants that can cause serious reproductive and developmental problems and linger in the human body for several years after the original exposure period. Though dioxins can be produced from natural events such as volcanic eruptions and forest fires, they can also be byproducts of industrial processes.
In a paper published online September 10, 2010 in the Journal of Bacteriology, a team of researchers including the DOE JGI’s Chris Detter and Elizabeth Saunders described the finished genome sequence of S. wittichii RW 1. Annotating the 5.9-million base pair genome led to the identification of the region where all the genes known to be involved in breaking down dioxin were located.
Additional key findings include the identification of receptors, which, the authors note, “may in part explain the unique ability of S. wittichii RW 1 to consume a wide range of sparingly water-soluble aromatic hydrocarbons.”