Identification of Amidase Negative Strains of Bacillus thuringiensis
Bacillus thuringiensis is a gram positive spore forming bacterium that produces crystal proteins which are toxic to many species of insects. Bt is largely used in agriculture, especially organic farming as a bioinsecticide. Bt is also used in urban aerial spraying programs, and in transgenic crops. Amidase is the enzyme that breaks down the cell wall structure of the mother cell or sporangium, which exposes the crystal proteins to UV irradiation and thus neutralization. Therefore, the Bt cells that do not have Amidase genes are possible target for genetic engineering for crystal protein products because the crystal protein inside the sporangium or mother cell is protected from U.V light. In the work reported here DNA was extracted from 74 strains of Bt and subjected to PCR analysis using eight different sets of primers to detect Amidase genes in each strain. It was found that most of the strains tested yielded PCR products from each of the primers. However, several strains were found to not produce a PCR product by five of the primer sets. Thus, it was concluded that these strains will serve as targets for further study to develop a Bt strain that does not break down the sporangium.
Sarah Zakaria Filfilan,
"Identification of Amidase Negative Strains of Bacillus thuringiensis"
ETD Collection for Tennessee State University.