Biodegradation of Xenobiotics and Toxic Wastes - Bacteria can be modified genetically to develop catabolic pathways for degradation of xenobiotics (wastes from nonbiological systems) and other waste material. Bacterial genes for this purpose arc isolated from bacterial strains (or their plasmids) found at waste sites.
Most of these genes are available front gram negative bacteria (e.g. Pseudomonas spp.), which are themselves not very efficient degraders, since multiple genes may sometimes be needed for efficient biodegradation.
Therefore, for efficient biodegradation, efficient degraders have to be prepared through genetic engineering and they need to be established in the environment at a required density.