title: Simultaneous degradation of organophosphorus pesticides and p-nitrophenol by a genetically engineered Moraxella sp. with surface-expressed organophosphorus hydrolase.
abstract: Moraxella sp., a native soil organism that grows on p-nitrophenol (PNP), was genetically engineered for the simultaneous degradation of organophosphorus (OP) pesticides and p-nitrophenol (PNP). The truncated ice nucleation protein (INPNC) anchor was used to target the pesticide-hydrolyzing enzyme, organophosphorus hydrolase (OPH), onto the surface of Moraxella sp., alleviating the potential substrate uptake limitation. A shuttle vector, pPNCO33, coding for INPNC-OPH was constructed and the translocation, surface display, and functionality of OPH were demonstrated in both E. coli and Moraxella sp. However, whole cell activity was 70-fold higher in Moraxella sp. than E. coli. The resulting Moraxella sp. degraded organophosphates as well as PNP rapidly, all within 10 h. The initial hydrolysis rate was 0.6 micromol/h/mg dry weight, 1.5 micromol/h/mg dry weight, and 9.0 micromol/h/mg dry weight for methyl parathion, parathion, and paraoxon, respectively. The possibility of rapidly degrading OP pesticides and their byproducts should open up new opportunities for improved remediation of OP nerve agents in the future.
authors.affiliation: Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, USA.
authors.forename: M
authors.initials: M
authors.lastname: Shimazu
authors.forename: A
authors.initials: A
authors.lastname: Mulchandani
authors.forename: W
authors.initials: W
authors.lastname: Chen
mesh_terms: D043303:Aryldialkylphosphatase; D015153:Blotting, Western; D004926:Escherichia coli / Q000378:metabolism; D004950:Esterases / Q000378:metabolism*; D005818:Genetic Engineering; D005822:Genetic Vectors / Q000235:genetics; D006868:Hydrolysis; D007306:Insecticides / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D009016:Moraxella / Q000201:enzymology*; D009596:Nitrophenols / Q000378:metabolism*; D009943:Organophosphorus Compounds; D010957:Plasmids / Q000378:metabolism; D021381:Protein Transport; D013347:Subcellular Fractions / Q000378:metabolism; D013997:Time Factors
chemical_list: D007306:Insecticides; D009596:Nitrophenols; D009943:Organophosphorus Compounds; D004950:Esterases; D043303:Aryldialkylphosphatase; C024836:4-nitrophenol