Composition of the Putative Prepore Complex of Bacillus thuringiensis Cry1Ab Toxin

Manoj S. Nair^1,2*, Donald H. Dean¹

¹Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA.
²Aaron Diamond AIDS Research Center, Rockefeller University, New York, NY, USA.

DOI: 10.4236/abc.2015.54014                

Abstract

Prepore formation is hypothesized to be an obligate step in the insertion of Cry1Ab toxin into insect brush border membrane vesicles. We examined the architecture of the putative prepore when isolated using the published protocols [1] [2]. Our results demonstrate that the putative prepore form of Cry1Ab is a combination of receptor proteins attached to the toxin, when purified. The results also suggest that this prepore form as prepared by the methods published is different from other membrane-extracted oligomeric forms of Cry toxins and prepore of other toxins in general. While most other known prepores are composed of multimers of a single protein, the Cry1Ab prepore, as generated, is a protein-receptor complex oligomer and monomers of Cry toxins.

Keywords

Cry1Ab Protein, Protein-Receptor Interactions, Brush Border Membrane Vesicles, Small Unilamellar Vesicles, Prepore, LC-MS/MS

Conflicts of Interest

The authors declare no conflicts of interest.

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