Purification Of A Fungal Activator From Alternaria Strain And Its Gene Cloning & Expression

In this paper, the definition and classification of biopesticide was introduced, and the research development of new microbial proteinaceous pesticide reviewed. Fungal activator is a novel microbial proteinaceous pesticide, which is multifunctional, high efficient, no residue, environment-friendly, and safety to natural enemy. Its action mechanism is similar to that of animal immunity. In this article, the developmental trend and application potential of this new microbial protein pesticide was reviewed.In this study, a fungal activator, approximately Mr. 42KD,was purified from Alternaria axo strain and sequenced. A partial fungal activator gene np45 was obtained by using PCR technique. Bacterial fusion expressed vectors of np45 gene was constructed and successfully expressed in E.coli , named by NP45. Analysis of NP45 at GeneBank Blast showed that the identity between NP45 and USDA 110 blr0937 from Bradyrhizobium japonicum was 19.14%, the highest score in bacteria. Furthermore, the identity of NP45 and FGSC A4 sequence number AN0215.2 from Aspergillus nidulans was 53.78%, the highest score in fungi. There was no homology between NP45 and other known microbial proteinaceous pesticides, such as harpin, elicitin. This result indicated that, np45 was a new kind of gene, and NP45 a novel protein.