Binding of Phylogenetically Distant Bacillus thuringiensis Cry Toxins to a Bombyx mori Aminopeptidase N Suggests Importance of Cry Toxin's Conserved Structure in Receptor Binding |
| |
| Authors: | Ayaka Shinkawa Katsuro Yaoi Tomoyuki Kadotani Morikazu Imamura Nobuo Koizumi Hidenori Iwahana Ryoichi Sato |
| |
| Institution: | (1) Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan , JP;(2) Department of Applied Biological Science, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-0054, Japan , JP |
| |
| Abstract: | We investigated the binding proteins for three Cry toxins, Cry1Aa, Cry1Ac, and the phylogenetically distant Cry9Da, in the
midgut cell membrane of the silkworm. In a ligand blot experiment, Cry1Ac and Cry9Da bound to the same 120-kDa aminopeptidase
N (APN) as Cry1Aa. A competition experiment with the ligand blot indicated that the three toxins share the same binding site
on several proteins. The values of the dissociation constants of the three Cry toxins and 120-kDa APN are as low as the case
of other Cry toxins and receptors. These results suggest that distantly related Cry toxins bind to the same site on the same
proteins, especially with APN. We propose that the conserved structure in these three toxins includes the receptor-binding
site.
Received: 12 January 1998 / Accepted: 17 February 1999 |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
