Previous Article | Next Article ![]()
Appl. Environ. Microbiol., Oct 1996, 3581-3586, Vol 62, No. 10
A Regev, M Keller, N Strizhov, B Sneh, E Prudovsky, I Chet, I Ginzberg, Z Koncz- Kalman, C Koncz, J Schell and A Zilberstein
In an attempt to increase the insecticidal effect of the delta- endotoxin
crystal protein CryIC on the relatively Cry-insensitive larvae of
Spodoptera littoralis, a combination of CryIC and endochitinase was used.
CryIC comprising the first 756 amino acids from Bacillus thuringiensis
K26-21 and endochitinase ChiAII encoded by Serratia marcescens were
separately produced in Escherichia coli carrying the genes in
overexpression vectors. The endochitinase on its own, even at very low
concentrations (0.1 microgram/ml), perforated the larval midgut peritrophic
membrane. When applied together with low concentrations of CryIC, a
synergistic toxic effect was obtained. In the absence of chitinase, about
20 micrograms of CryIC per ml was required to obtain maximal reduction in
larval weight, while only 3.0 micrograms of CryIC per ml caused a similar
toxic effect in the presence of endochitinase. Thus, a combination of the
Cry protein and an endochitinase could result in effective insect control
in transgenic systems in which the Cry protein is not expressed in a
crystalline form.
Copyright © 1996, American Society for Microbiology
Synergistic activity of a Bacillus thuringiensis delta-endotoxin and a bacterial endochitinase against Spodoptera littoralis larvae
Department of Botany, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Israel.
This article has been cited by other articles:
| J. Bacteriol. | Microbiol. Mol. Biol. Rev. | Eukaryot. Cell | All ASM Journals |
|---|