title: Binding affinity of the methyl ester of AK-toxin I to membrane fractions from Japanese pear leaves.
abstract: The binding site of AK-toxin, a host-specific toxin against Japanese pear, was searched for in the membrane fractions of the pear leaves, using 3H-labeled AK-toxin I methyl ester. Binding activity, which was displaceable by the unlabeled ligand, was observed for microsomal fraction from a toxin-susceptible cultivar, Nijisseiki. However, the binding was also observed for those from toxin-resistant cultivars, Kosui and Hosui. Detection of the specific binding failed for the plasma membrane fraction which was prepared from microsomal fraction of the toxin-susceptible cultivar by aqueous two-phase separation, and the hitherto presumed model of the AK-toxin receptor in the plasma membrane could not be verified.
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Okada
authors.forename: H
authors.initials: H
authors.lastname: Miyagawa
authors.forename: Y
authors.initials: Y
authors.lastname: Nakagawa
authors.forename: T
authors.initials: T
authors.lastname: Ueno
mesh_terms: D001667:Binding, Competitive; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000737:chemistry / Q000494:pharmacology*; D008861:Microsomes / Q000187:drug effects / Q000378:metabolism; D009183:Mycotoxins / Q000737:chemistry / Q000494:pharmacology*; D010649:Phenylalanine / Q000031:analogs & derivatives / Q000737:chemistry / Q000494:pharmacology*; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism; D019685:Rosales / Q000187:drug effects* / Q000378:metabolism
chemical_list: C421190:AK-toxin I; D005231:Fatty Acids, Unsaturated; D009183:Mycotoxins; D010649:Phenylalanine