Construction of a genetically engineered microorganism for degrading organophosphate and carbamate pesticides

Genetically engineered microorganisms (GEMs) have shown potential for enhanced degradation of a range of substrates. In this study, a DNA fragment including the open reading frame of mpd (methyl parathion hydrolase encoding gene) and cognate regulator of a methyl parathion (MP)-degrading strain Pseudomonas putida DLL-1 was cloned by the shotgun method. The fragment was cloned into a broad-host vector pBBR1MCS-2 to produce a recombinant plasmid pBBR-mpd. CDS-pBBR-mpd, a GEM, was successfully constructed by transforming it into a carbofuran-degrading strain Sphingomonas sp. CDS-1, and it degraded both carbofuran and MP. CDS-pBBR-mpd maintained stable and high MP hydrolase activity (50.72 nmol min−1 μg−1 protein, which was 6.57 times higher than that of P. putida strain DLL-1). and appears to be a promising GEM for environmental bioremediation.