Cry1Ac protoxin from Bacillus thuringiensis sp. kurstaki HD73 binds to surface proteins in the mouse small intestine

Biochem Biophys Res Commun. 2000 Apr 29;271(1):54-8. doi: 10.1006/bbrc.2000.2584.


Bacillus thuringiensis (Bt), considered a safe insecticide, produces insecticidal proteins named Cry during sporulation, which possess exceptional immunological properties. In this work using an immunohistochemical test we demonstrated that Cry1Ac protoxin (pCry1Ac) binds to the mucosal surface of the mouse small intestine. Ligand blot assay allowed us to detect, under denaturing conditions, six pCry1Ac-binding polypeptides present in brush border membrane vesicles isolated from the small intestine. Moreover, this protein induced in situ temporal changes in the electrophysiological properties of the mouse jejunum. The data obtained indicate a possible interaction in vivo of Cry proteins with the animal bowel which could induce changes in the physiological status of the intestine.

MeSH terms

  • Animals
  • Bacillus thuringiensis / chemistry*
  • Bacillus thuringiensis Toxins
  • Bacterial Proteins / metabolism*
  • Bacterial Toxins*
  • Electrophysiology
  • Endotoxins / metabolism*
  • Escherichia coli / metabolism
  • Fluorescent Antibody Technique
  • Hemolysin Proteins
  • Intestine, Small / metabolism*
  • Intestine, Small / microbiology*
  • Jejunum / metabolism
  • Ligands
  • Male
  • Membrane Proteins / metabolism*
  • Mice
  • Mice, Inbred BALB C
  • Microvilli / metabolism
  • Plants, Genetically Modified / metabolism
  • Protein Binding
  • Recombinant Proteins / metabolism
  • Time Factors


  • Bacillus thuringiensis Toxins
  • Bacterial Proteins
  • Bacterial Toxins
  • Endotoxins
  • Hemolysin Proteins
  • Ligands
  • Membrane Proteins
  • Recombinant Proteins
  • insecticidal crystal protein, Bacillus Thuringiensis