Organophosphonate Degradation
 

Inorganic phosphate is a fundamental building block in biological systems. It is used for storage of energy (ATP), genetic information (DNA, RNA), cell signalling, and many other roles that are essential for life. Not surprisingly, microbes have evolved enzyme systems to produce inorganic phosphate from alternate forms of phosphorus, including phosphate esters, hypophosphite, phosphite, and organophosphonates. Enzymatic degradation of the latter class of molecule, which is characterized by a highly stable carbon-phosphorus bond, is very interesting from a mechanistic perspective, as well as a potential means of degrading toxic organophosphonates, such as herbicides, insecticides, and nerve agents. We are currently studying the bacterial enzyme system called carbon-phosphorus lyase. CP-lyase is remarkable not only for its complexity (14 enzymes), but also for the range of organophosphonates it can degrade. Although CP-lyase is widely distributed amongst many bacterial species, it is reasonable to hypothesize that microbes evolved other ways to degrade organophosphonates. To this end we are also using genomic screens to discover new types of CP-bond cleaving systems, and new enzyme mechanisms.