[Construction of genetic engineering microogranism of salt tolerant degrading strain]

H1 ( Halomonas sp.) was a strain of salt tolerance (18% NaCl, W/V) and degrading phenylacetic acid, plasmid pDT3 was a derivation of pUC19 inserted mpd gene (methyl parathion degrading gene), which is obtained from methyl parathion (MP) degrading strain DLL-E4 (Pseudomonas putida). Recombinant plasmids pKT-MP and pBBR-MP were constructed by inserting Hind III fragment (which include whole mpd gene) of pDT3 into broad host vector pKT230 and pBBR1-MCS2. With the aid of help-plasmid pRK2013, pKT-MP and pBBR-MP were transferred into H1 (called tri-parent conjugation) and multi-functioned GEMs H-pKT-MP and H-pBBR-MP were constructed, which were salt tolerant, phenylacetic acid-degrading and MP-degrading. The activity of MP hydrolase of H-pBBR-MP and H-pKT-MP was 1 x and 2 x the one of DLL-E4. The MP hydrolase activity of two GEMs were constant.