Biotechnological opportunities with the β-ketoadipate pathway.

The β-ketoadipate pathway (β-KAP) is an enzyme-mediated aryl-ring degradation sequence employed by a wide selection of soil bacteria and fungi to reconcile the conversion of many hazardous aromatic pollutants into benign metabolites of the tricarboxylic acid cycle (TCA), lipogenesis, and other anabolic processes. Recently determined catabolic sequences that incorporate the β-KAP allow thorough mineralization of toxic priority pollutants including hazardous nitrophenols, organophosphates, and polychlorinated arenes and hydrocarbons. Novel investigations have applied the β-KAP via oleaginous microorganisms to convert aromatic lignocellulosic waste into bio-oils that are suitable for biodiesel applications. These newly elucidated catabolic pathways and applications, reviewed here, provide exciting and unparalleled biotechnological opportunities for the future.