Abstract
Cyt1Aa is the major and most active component of the parasporal crystal of the Gram-positive soil entomopathogenic bacterium Bacillus thuringiensis subsp. israelensis. The Cyt1Aa protoxin exhibits some hemolytic and cytolytic activity. However, highly active 22-25 kDa toxins are obtained after proteolysis of Cyt1Aa from both the N- and the C-termini. As shown in this study, preliminary binding of the protoxin to polylamellary liposomes or partial denaturation of Cyt1Aa and further processing by several exogenous proteases yielded short 4. 9-11. 5 kDa cytolytic peptide fragments of Cyt1Aa. The shortest 51 amino acid peptide was obtained after pre-incubation of Cyt1Aa with SDS and proteolysis with proteinase K. This peptide was purified, identified as the Ile87-Asp137 fragment of Cyt1Aa and was shown to exhibit more than 30 % hemolysis of rabbit erythrocytes.
| Original language | English |
|---|---|
| Pages (from-to) | 121-127 |
| Number of pages | 7 |
| Journal | Cell Biochemistry and Biophysics |
| Volume | 65 |
| Issue number | 2 |
| DOIs | |
| State | Published - Mar 2013 |
Bibliographical note
Funding Information:Acknowledgments This research was supported in part by the Research Authority of the Ariel University Center of Samaria and the Rappaport Foundation for Medical Microbiology, Bar-Ilan University, Israel (to YN).
Funding
Acknowledgments This research was supported in part by the Research Authority of the Ariel University Center of Samaria and the Rappaport Foundation for Medical Microbiology, Bar-Ilan University, Israel (to YN).
| Funders | Funder number |
|---|---|
| Ariel University Center of Samaria | |
| Rappaport Foundation for Medical Microbiology, Bar-Ilan University, Israel |
Keywords
- Bacillus thuringiensisisraelensis
- Cyt1Aa
- Cytolytic peptides
- Liposomes
- Proteolysis