NOOMANSIDDIQUE, M. AMIN-ULMANNAN AND ATUL KUMAR UPADHYAY
Abstract
Bacillus thuringiensis (Bt) is a bacterium present in soil having bio pesticidal activity. A special class of protein known as d-endotoxins is responsible for this unique and useful activity. Deltaendotoxins are made up of three domains having specific functions. Domain I at N-terminal of dendotoxin is comprised of six helices. Domain II is made of three antiparallel β-sheets and is responsible for specificity towards different groups of insects. Domain III consists of two antiparallel β-sheets, which is a β-sandwich structure. Many plant bioengineering attempts were carried out to transfer cry genes ofBt to different crop plant species. Understanding the mechanism of regulation and mode of action of cry genes and proteins will help in devising better transgenic plants with wider range of resistance against crop pests, ultimately saving environmental pollution with enhanced productivity. In this review, we have discussed the basics of endotoxins, its mode of action along with classification, structure and function. A special emphasis is given on the genome, transcripotme and proteome of Bt. This review paper will be used as preliminary resource for the information about endotoxins and Bt genome.