Microbial degradation of toxic, environmental pollutants: Ecological and evolutionary considerations

Microorganisms are the major scavengers in nature, responsible for recycling most natural waste materials into harmless compounds. When faced with an increasing array of synthetic compounds, such as various chlorinated compounds manufactured by the chemical industry for use as herbicides/pesticides, industrial solvents, refrigerants, etc., the microorganisms attempt to evolve new genes, particularly for simple lowly chlorinated compounds, encoding enzymes that use the chlorinated compounds as their primary substrates. An understanding of how new biodegradative genes evolve in nature is therefore of the utmost importance to enhance the rate and the range of biodegradative processes. The various parameters that influence both natural as well as selective evolutionary processes are discussed.