Diversity Of Organophosphorus Hydrolase Genes And Analysis Of Microbial Community In Organophosphorus Polluted Soil

Organphosphorus (OP) compounds which were invented in 1940s are widely used as highly efficient and broad-spectrum insecticides. OPs have made great contribution to the development of human society during the half of a century. However, more and more problems about environment pollution, human health and continuable development begin to come out along with long-time and wide use of OPs. Organphosphorus hydrolase can destroy O-P bond of OPs, and consequently the toxicity of OPs is eliminated. The products of highly efficient and cheap organphosphrous hydrolase enzyme by the method of biotechnology are the best potential choice to solve those problems. A Bead Beating Plus Column(RBB+C) Method has been performed to recover metegenomic DNA from the organophosphorus (OP) polluted soil. According to the conservative domains of the organophosphorus hydrolase, the degenerate primers were designed to amplify the partial organophosphorus hydrolase genes. The DNA library of the partial organophosphorus hydrolase genes was constructed by pEASY-T3. The DNA sequences of the positive clones selected randomLy from the library were analysize to evaluate the diversity of organophosphorus hydrolase genes in polluted soil. The results showed that in the DNA library of the partial organophosphorus hydrolase genes, 88% from the OP-polluted soil and 97% from the activated sludge respectively shared 44%～65% and 23%～77% similarities with the genes reported in GenBank. It indicates that there were diversed and novel organophosphorus hydrolase genes in the OP-polluted soil and activated sludge. The microorganism diversity of polluted soil was also studied by PCR-DGGE.We hopefully could explain the mechanism of thermostability and catalysis of methyl parathion hydrolase through the study of the molecular structure of MPHXW and OPHC2 which are very different in sequences and enzymatic activity.