Xie Bingyan

Phylogentic analysis of type I polyketide synthase and nonribosomal peptide synthetase genes from Mila Mountain in Tibet plateau

The modular polyketide synthase(PKS) and nonribosomal peptide synthetase(NRPS) were found to be involved in natural product synthesis in many microorganisms.Study on their diversities in natural environment may provide important ecological insights besides opportunities for antibacterial drugs development.The phylogenetic analysis of amino acid(AA) sequences indicated that the identified ketosynthase(KS) domains were clustered with those from diverse bacterial groups,including Cyanobaeteria,Proteobaeteria and some uncultured symbiotic bacteria.The NRPS included Cyanobaeteria and Proteobaeteria.One new branch belonging to hybrid PKS/NRPS enzyme complexes and five independent clades were found on the phylogenetic tree.These results revealed the great diversity and novelty of both PKS and NRPS genes from Mila Mountain in Tibetan Plateau.

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.