16. Promise of Bacillus thuringiensis Crystal Proteins as Anthelmintics

  1. Dr. Conor R. Caffrey
  1. Yan Hu and
  2. Raffi V. Aroian

Published Online: 23 AUG 2012

DOI: 10.1002/9783527652969.ch16

Parasitic Helminths: Targets, Screens, Drugs and Vaccines

Parasitic Helminths: Targets, Screens, Drugs and Vaccines

How to Cite

Hu, Y. and Aroian, R. V. (2012) Promise of Bacillus thuringiensis Crystal Proteins as Anthelmintics, in Parasitic Helminths: Targets, Screens, Drugs and Vaccines (ed C. R. Caffrey), Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, Germany. doi: 10.1002/9783527652969.ch16

Editor Information

  1. Sandler Center for Drug Discovery and Department of Pathology, University of California San Francisco, Byers Hall 501E, 1700 4th Street, San Francisco, CA 94158-2330, USA

Author Information

  1. University of California San Diego, Section of Cell and Developmental Biology, Division of Biological Sciences, 9500 Gilman Dr, La Jolla, CA 92093-0322, USA

Publication History

  1. Published Online: 23 AUG 2012
  2. Published Print: 18 JUL 2012

Book Series:

  1. Drug Discovery in Infectious Diseases

Book Series Editors:

  1. Prof. Dr. Paul M. Selzer

Series Editor Information

  1. Intervet Innovation GmbH, MSD Animal Health, Molecular Discovery Sciences, Zur Propstei, 55270 Schwabenheim, Germany

ISBN Information

Print ISBN: 9783527330591

Online ISBN: 9783527652969



  • Bacillus thuringiensis;
  • crystal protein;
  • anthelmintic;
  • insecticide;
  • roundworm;
  • parasite


Bacillus thuringiensis crystal (Cry) proteins are the most widely used biological insecticides in the world. Their value in safely controlling insects that destroy crops and transmit human diseases is well established. Here, we review B. thuringiensis Cry proteins as novel anthelmintics with a unique mode of action. In laboratory studies, Cry proteins are highly effective against a broad range of free-living roundworms and parasitic roundworms that infect plants and animals. Cry5B is therapeutic for two different intestinal roundworm parasitic infections – one in mice and the other in hamsters. The latter infection involves a minor hookworm parasite of humans, Ancylostoma ceylanicum, which is closely related to the more prevalent Ancylostoma duodenale. Therapy is observed despite the fact that much of the protein is likely degraded in the stomach prior to reaching the parasites. Cry21A is also therapeutic in mice infected with the roundworm parasite, Heligmosomoides bakeri. Cry proteins offer excellent combinatorial therapeutic properties with nicotinic acetylcholine receptor agonists – one of two classes of compounds approved by the World Health Organization for treatment of intestinal roundworms in humans. Given their nontoxicity to humans and their broad spectrum of nematicidal action, Cry proteins show great potential as next-generation anthelmintics.