Comparative study of Bacillus thuringiensis Cry1Ia and Cry1Aa delta-endotoxins: activation process and toxicity against Prays oleae

Journal of Invertebrate Pathology
Mariam DammakSamir Jaoua

Abstract

Cry1Ia and Cry1Aa proteins exhibited toxicities against Prays oleae with LC(50) of 189 and 116 ng/cm(2), respectively. The ability to process Cry1Ia11 protoxin by trypsin, chymotrypsin and P. oleae larvae proteases was studied and compared to that of Cry1Aa11. After solubilization under high alkaline condition (50mM NaOH), Cry1Aa11 was converted into a major fragment of 65 kDa, whereas Cry1Ia11 protoxin was completely degraded by P. oleae larvae proteases and trypsin and converted into a major fragment of 70 kDa by chymotrypsin. Using less proteases of P. oleae juice, the degradation of Cry1Ia11 was attenuated. When the solubilization (in 50mM Na(2)CO(3) pH 10.5 buffer) and activation were combined, Cry1Ia11 was converted into a proteolytic product of 70 kDa after 3h of incubation with trypsin, chymotrypsin and P. oleae juice. These results suggest that the in vivo solubilization of Cry1Ia11 was assured by larval proteases after a swelling of the corresponding inclusion due to the alkalinity of the larval midgut.

References

Jan 24, 2002·Insect Biochemistry and Molecular Biology·Johann P SchernthanerHarvey Kaplan

❮ Previous
Next ❯

Citations

Jul 1, 2014·Journal of Insect Physiology·Silvia CacciaJuan Ferré
May 21, 2014·Preparative Biochemistry & Biotechnology·Dorra Ben Hamadou-CharfiDietrich Stephan

❮ Previous
Next ❯

Related Concepts

Related Feeds

Bacterial Cell Wall Structure (ASM)

Bacterial cell walls are made of peptidoglycan (also called murein), which is made from polysaccharide chains cross-linked by unusual peptides containing D-amino acids. Here is the latest research on bacterial cell wall structures.

Bacterial Cell Wall Structure

Bacterial cell walls are made of peptidoglycan (also called murein), which is made from polysaccharide chains cross-linked by unusual peptides containing D-amino acids. Here is the latest research on bacterial cell wall structures.