Bacillus thuringiensis/Insecticidal protein

特許 権利維持 B. thuringiensis was first discovered in 1901 by Japanese biologist Ishiwata Shigetane.[3] In 1911, B. thuringiensis was rediscovered in Germany by Ernst Berliner, who isolated it as the cause of a disease called Schlaffsucht in flour moth caterpillars. In 1976, Robert A. Zakharyan reported the presence of a plasmid in a strain of B. thuringiensis and suggested the plasmid's involvement in endospore and crystal formation.[4][5] B. thuringiensis is closely related to B.cereus, a soil bacterium, and B.anthracis, the cause of anthrax; the three organisms differ mainly in their plasmids.[6]:34–35 Like other members of the genus, all three are aerobes capable of producing endospores.[1] Upon sporulation, B. thuringiensis forms crystals of proteinaceous insecticidal δ-endotoxins (called crystal proteins or Cry proteins), which are encoded by cry genes.[7] In most strains of B. thuringiensis, the cry genes are located on a plasmid (cry is not a chromosomal gene in most strains).