Genetic Factors Affecting Insecticidal Crystal Protein Synthesis in Bacillus thuringiensis

Early studies of the molecular biology of Bacillus thuringeinsis suggested that genetic manipulation of this species could create combinations of genes more useful than those known to occur in natural isolates. Breakthroughs that made these manipulations possible include the cloning of many genes encoding endotoxins, the development of transformation vectors, and various PCR techniques. This paper reviews several genetic factors such as promoters, a 5'mRNA stabilizing sequence, 3'transcription termination sequences, and helper proteins that have been used to enhance crystal protein synthesis, and shows how these genetic elements can be manipulated with new molecular tools to develop more efficacious strains of B. thuringiensis.