What is Bacillus thuringiensis (Bt)?
Bacillus thuringiensis (or Bt) is a common gram positive, spore-forming, soil bacterium. When resources are limited, vegetative Bt cells undergo sporulation, synthesizing a protein crystal during spore formation. Proteins in these crystals are called Cry (from Crystal) endotoxins and have been known for decades to display insecticidal activity against specific insect groups. Even though insecticidal formulations based on Bt toxins have been used for many years, it was the development and commercialization of insect-resistant transgenic Bt crops expressing Cry toxins that revolutionized the history of agriculture. Benefits of this technology include high specificity and potency, reduction in chemical pesticide applications, and increased crop yield.
Bt spore and crystal
Our group is currently working on characterizing how Cry toxins kill insects. Current active areas of research in our lab related to Cry toxin mode of action include (select for more information):