Cytolytic peptide fragments of Cyt1Aa from Bacillus thuringiensis subsp. israelensis.

Marina Nisnevitch, Svetlana Nikonov, Yeshayahu Nitzan

Department of Chemical Engineering, Biotechnology and Materials, Ariel University Center of Samaria, Ariel, Israel. marinan@ariel.ac.il

Cell biochemistry and biophysics 2013 Mar

filter terms:

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.

Citation

Marina Nisnevitch, Svetlana Nikonov, Yeshayahu Nitzan. Cytolytic peptide fragments of Cyt1Aa from Bacillus thuringiensis subsp. israelensis. Cell biochemistry and biophysics. 2013 Mar;65(2):121-7