Zhang Deyong

Kinetics biodegradation of triazophos by Klebsiella oxytoca TDB-1

A triazophos (TAP)-degrading bacterial strain, Klebsiella oxytoca TDB-1, which could use TAP as sole carbon source, was isolated by enrichment culture technology. The growth characteristics of strain TDB-1 with pressure of TAP were tested, and the results show that optimum growth condition was at 30°C, pH 8 and 2% (v/v) inoculation. Strain TDB-1 was great promise in TAP biodegradation for extreme pH tolerance (pH 4 and 10). The kinetic of strain TDB-1 in degrading TAP followed first-order model under optimal growth conditions. Cell surface hydrophobicity (CSH) assays of strain TDB-1 reflected that the strain TDB-1 was of higher hydrophobicity while grown on higher concentration of TAP. The growth and TAP-biodegradation characteristics of strain TDB-1 revealed that it would be an excellent alternative degrader for bioremediation of TAP contaminants, especially for that with extreme pH, such as some industrial wastewaters.

Construction of dsRNA vector for a viral binding protein gene (groEL) from endosymbionts in Bemisia tabaci and its expression analysis in transgenic Nicotiana benthamianaa.

GroEL,a viral binding protein encoding by groEL gene from endosymbionts in Bemisia tabaci,is an important factor in transmission of plant viruses.In this study,502 bp fragment of groEL was amplified by polymerase chain reaction(PCR) and then ligated to the plant expression vector pBIN19.The recombination vector pBIN19::groEL was transformed into Agrobacterium tumefaciens strain LBA4404 by electroporation.Transgenic Nicotiana benthamiana plants were acquired by Agrobacterium-mediated approach.PCR and RT-PCR were performed to analyze groELs transformation and expression in transgenic plants,respectively.The results indicated that groEL gene was not only integrated into chromosome DNA of transgenic N.benthamiana,but also transcribed in transgenic plants successfully.