Evolution of efficient pathways for degradation of anthropogenic chemicals.
Anthropogenic compounds used as pesticides, solvents and explosives often persist in the environment and can cause toxicity to humans and wildlife. The persistence of anthropogenic compounds is due to their recent introduction into the environment; microbes in soil and water have had relatively little time to evolve efficient mechanisms for degradation of these new compounds. Some anthropogenic compounds are easily degraded, whereas others are degraded very slowly or only partially, leading to accumulation of toxic products. This review examines the factors that affect the ability of microbes to degrade anthropogenic compounds and the mechanisms by which new pathways emerge in nature. New approaches for engineering microbes with enhanced degradative abilities include assembly of pathways using enzymes from multiple organisms, directed evolution of inefficient enzymes, and genome shuffling to improve microbial fitness under the challenging conditions posed by contaminated environments.
Copley
Shelley D
SD
Department of Molecular, Cellular and Developmental Biology and Cooperative Institute for Research in Environmental Sciences, University of Colorado at Boulder, Boulder, Colorado, USA. shelley@cires.colorado.edu
D000818:Animals; D001419:Bacteria / Q000201:enzymology* / Q000254:growth & development; D001665:Binding Sites; D001673:Biodegradation, Environmental; D004785:Environmental Pollutants / Q000032:analysis / Q000737:chemistry*; D004798:Enzymes / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008958:Models, Molecular; D012988:Soil Microbiology; D013379:Substrate Specificity
D004785:Environmental Pollutants; D004798:Enzymes