The primary aim of the research is to determine the complete genome sequence of Bacillus thuringiensis (Bt). This information will be used to find novel genes that contribute to the function of this beneficial microorganism. Bt is a ubiquitous bacterium that has been isolated from a variety of sites including soil, stored grain, insects and plant surfaces. The most distinctive property of Bt is the production of insecticidal proteins (Cry toxins). Cry toxin activity affects several insects, including moths, butterflies, mosquitoes, black flies, beetles, hoppers, aphids, wasps, bees and soil nematodes. Consequently, Cry toxins have been exploited for more than 40 years to control agriculturally and medically important pest and disease-vector insects. Indeed, Bt is the most widely used environmentally compatible biopesticide worldwide. Significantly, Bt exists in a symbiotic relationship with invertebrate animals as well as plants. Thus, Bt is an excellent model to address questions related to microbe-host interactions in symbiotic and pathogenic relationships. Therefore, sequencing the Bt genome will expand the understanding of bacterial disease in insects and nematodes, and enhance the ability to exploit Bt for environmentally safe pest control. This information also will be important for understanding human and animal disease. Bt is closely related to a group of organisms that includes Bacillus cereus (Bc), an opportunistic human pathogen, and Bacillus anthracis (Ba), a bioterrorism pathogen. Therefore, comparison of the Bt genome with those of Ba and Bc will illuminate differences in their host-pathogen relationships. Thus, the broader impact of the research will lay the groundwork for future investigations to resolve basic problems in agriculture (environmentally safe pest control), medicine and biodefense.