Crystal structure of insecticidal delta-endotoxin from Bacillus thuringiensis at 2.5 A resolution

Nature. 1991 Oct 31;353(6347):815-21. doi: 10.1038/353815a0.


The structure of the delta-endotoxin from Bacillus thuringiensis subsp. tenebrionis that is specifically toxic to Coleoptera insects (beetle toxin) has been determined at 2.5 A resolution. It comprises three domains which are, from the N- to C-termini, a seven-helix bundle, a three-sheet domain, and a beta sandwich. The core of the molecule encompassing all the domain interfaces is built from conserved sequence segments of the active delta-endotoxins. Therefore the structure represents the general fold of this family of insecticidal proteins. The bundle of long, hydrophobic and amphipathic helices is equipped for pore formation in the insect membrane, and regions of the three-sheet domain are probably responsible for receptor binding.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Bacillus thuringiensis
  • Bacterial Proteins*
  • Bacterial Toxins*
  • Binding Sites
  • Computer Graphics
  • Endotoxins / chemistry*
  • Endotoxins / metabolism
  • Hemolysin Proteins
  • Models, Molecular
  • Molecular Sequence Data
  • Protein Conformation
  • Receptors, Immunologic / metabolism
  • Solubility
  • Thermodynamics
  • X-Ray Diffraction / methods


  • Bacterial Proteins
  • Bacterial Toxins
  • Endotoxins
  • Hemolysin Proteins
  • Receptors, Immunologic
  • endotoxin receptor
  • insecticidal crystal protein, Bacillus Thuringiensis