AEM
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
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 Google Scholar
Google Scholar
Right arrow Articles by Klein, D.
Right arrow Articles by Braun, S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Klein, D.
Right arrow Articles by Braun, S.
Agricola
Right arrow Articles by Klein, D.
Right arrow Articles by Braun, S.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, July 2002, p. 3300-3307, Vol. 68, No. 7
0099-2240/02/$04.00+0     DOI: 10.1128/AEM.68.7.3300-3307.2002
Copyright © 2002, American Society for Microbiology. All Rights Reserved.

Tightly Bound Binary Toxin in the Cell Wall of Bacillus sphaericus

Daniela Klein, Igor Uspensky, and Sergei Braun*

Department of Biological Chemistry, A. Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel

Received 26 December 2001/ Accepted 11 April 2002

We have shown that urea-extracted cell wall of entomopathogenic Bacillus sphaericus 2297 and some other strains is a potent larvicide against Culex pipiens mosquitoes, with 50% lethal concentrations comparable to that of the well-known B. sphaericus binary toxin, with which it acts synergistically. The wall toxicity develops in B. sphaericus 2297 cultures during the late logarithmic stage, earlier than the appearance of the binary toxin crystal. It disappears with sporulation when the binary toxin activity reaches its peak. Disruption of the gene for the 42-kDa protein (P42) of the binary toxin abolishes both cell wall toxicity and crystal formation. However, the cell wall of B. sphaericus 2297, lacking P42, kills C. pipiens larvae when mixed with Escherichia coli cells expressing P42. Thus, the cell wall toxicity in strongly toxic B. sphaericus strains must be attributed to the presence in the cell wall of tightly bound 51-kDa (P51) and P42 binary toxin proteins. The synergism between binary toxin crystals and urea-treated cell wall preparations reflects suboptimal distribution of binary toxin subunits in both compartments. Binary toxin crystal is slightly deficient in P51, while cell wall is lacking in P42.

* Corresponding author. Mailing address: Department of Biological Chemistry, A. Silberman Institute of Life Sciences, The Hebrew University, Jerusalem 91904, Israel. Phone: 972-2-6585412. Fax: 972-2-6519597. E-mail: sergei{at}vms.huji.ac.il.

Applied and Environmental Microbiology, July 2002, p. 3300-3307, Vol. 68, No. 7
0099-2240/02/$04.00+0     DOI: 10.1128/AEM.68.7.3300-3307.2002
Copyright © 2002, American Society for Microbiology. All Rights Reserved.





Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. Microbiol. Mol. Biol. Rev. Eukaryot. Cell All ASM Journals

Copyright © 2002 by the American Society for Microbiology. All rights reserved.