This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Federici, B. A.
Right arrow Articles by Bauer, L. S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Federici, B. A.
Right arrow Articles by Bauer, L. S.
Agricola
Right arrow Articles by Federici, B. A.
Right arrow Articles by Bauer, L. S.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, November 1998, p. 4368-4371, Vol. 64, No. 11
0099-2240/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.

Cyt1Aa Protein of Bacillus thuringiensis Is Toxic to the Cottonwood Leaf Beetle, Chrysomela scripta, and Suppresses High Levels of Resistance to Cry3Aa

Brian A. Federici1,* and Leah S. Bauer2

Department of Entomology and Interdepartmental Graduate Programs in Genetics and Microbiology, University of California, Riverside, California 92521,1 and North Central Forest Experiment Station, Pesticide Research Center, USDA Forest Service, and Department of Entomology, Michigan State University, East Lansing, Michigan 488232

Received 8 May 1998/Accepted 8 August 1998

The insecticidal activity of Bacillus thuringiensis is due primarily to Cry and Cyt proteins. Cry proteins are typically toxic to lepidopterous, coleopterous, or dipterous insects, whereas the known toxicity of Cyt proteins is limited to dipterans. We report here that a Cyt protein, Cyt1Aa, is also highly toxic to the cottonwood leaf beetle, Chrysomela scripta, with a median lethal concentration of 2.5 ng/mm2 of leaf surface for second-instar larvae. Additionally, we show that Cyt1Aa suppresses resistance to Cry3Aa greater than 5,000-fold in C. scripta, a level only partially overcome by Cry1Ba due to cross-resistance. Studies of the histopathology of C. scripta larvae treated with Cyt1Aa revealed disruption and sloughing of midgut epithelial cells, indicating that its mechanism of action against C. scripta is similar to that observed in mosquito and blackfly larvae. These novel properties suggest that Cyt proteins may have an even broader spectrum of activity against insects and, owing to their different mechanism of action in comparison to Cry proteins, might be useful in managing resistance to Cry3 and possibly other Cry toxins used in microbial insecticides and transgenic plants.

* Corresponding author. Mailing address: Department of Entomology, University of California, Riverside, CA 92521. Phone: (909) 787-5006. Fax: (909) 787-3086. E-mail: brian.federici{at}ucr.edu.

Applied and Environmental Microbiology, November 1998, p. 4368-4371, Vol. 64, No. 11
0099-2240/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:

  • Itsko, M., Manasherob, R., Zaritsky, A. (2005). Partial Restoration of Antibacterial Activity of the Protein Encoded by a Cryptic Open Reading Frame (cyt1Ca) from Bacillus thuringiensis subsp. israelensis by Site-Directed Mutagenesis. J. Bacteriol. 187: 6379-6385 [Abstract] [Full Text]  
  • Sayyed, A. H., Crickmore, N., Wright, D. J. (2001). Cyt1Aa from Bacillus thuringiensis subsp. israelensis Is Toxic to the Diamondback Moth, Plutella xylostella, and Synergizes the Activity of Cry1Ac towards a Resistant Strain. Appl. Environ. Microbiol. 67: 5859-5861 [Abstract] [Full Text]  
  • Guerchicoff, A., Delécluse, A., Rubinstein, C. P. (2001). The Bacillus thuringiensis cyt Genes for Hemolytic Endotoxins Constitute a Gene Family. Appl. Environ. Microbiol. 67: 1090-1096 [Abstract] [Full Text]  
  • Meyer, S. K., Tabashnik, B. E., Liu, Y.-B., Wirth, M. C., Federici, B. A. (2001). Cyt1A from Bacillus thuringiensis Lacks Toxicity to Susceptible and Resistant Larvae of Diamondback Moth (Plutella xylostella) and Pink Bollworm (Pectinophora gossypiella). Appl. Environ. Microbiol. 67: 462-463 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»