title: Computer-assisted engineering of the synthetic pathway for biodegradation of a toxic persistent pollutant.
abstract: Anthropogenic halogenated compounds were unknown to nature until the industrial revolution, and microorganisms have not had sufficient time to evolve enzymes for their degradation. The lack of efficient enzymes and natural pathways can be addressed through a combination of protein and metabolic engineering. We have assembled a synthetic route for conversion of the highly toxic and recalcitrant 1,2,3-trichloropropane to glycerol in Escherichia coli, and used it for a systematic study of pathway bottlenecks. Optimal ratios of enzymes for the maximal production of glycerol, and minimal toxicity of metabolites were predicted using a mathematical model. The strains containing the expected optimal ratios of enzymes were constructed and characterized for their viability and degradation efficiency. Excellent agreement between predicted and experimental data was observed. The validated model was used to quantitatively describe the kinetic limitations of currently available enzyme variants and predict improvements required for further pathway optimization. This highlights the potential of forward engineering of microorganisms for the degradation of toxic anthropogenic compounds.
authors: Loschmidt Laboratories, Department of Experimental Biology and Research Centre for Toxic Compounds in the Environment, Faculty of Science, Masaryk University , Kamenice 5/A13, 625 00 Brno, Czech Republic.
authors: Nagendra Prasad
authors: NP
authors: Kurumbang
authors: Pavel
authors: P
authors: Dvorak
authors: Jaroslav
authors: J
authors: Bendl
authors: Jan
authors: J
authors: Brezovsky
authors: Zbynek
authors: Z
authors: Prokop
authors: Jiri
authors: J
authors: Damborsky
mesh_terms: D001426:Bacterial Proteins; D001673:Biodegradation, Environmental; D003198:Computer Simulation; D004785:Environmental Pollutants / Q000032:analysis / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005818:Genetic Engineering; D005990:Glycerol / Q000032:analysis / Q000378:metabolism; D060847:Metabolic Engineering / Q000379:methods*; D053858:Metabolic Networks and Pathways; D011407:Propane / Q000031:analogs & derivatives* / Q000032:analysis / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D004785:Environmental Pollutants; C009536:1,2,3-trichloropropane; D005990:Glycerol; D011407:Propane