Species-specific pheromonal compounds induce distinct conformational changes of pheromone binding protein subtypes from Antheraea polyphemus.
We have investigated the structural features of three pheromone binding protein (PBP) subtypes from Antheraea polyphemus and monitored possible changes induced upon interaction with the Antheraea pheromonal compounds 4E,9Z-14:Ac [(E4,Z9)-tetradecadienyl-1-acetate], 6E,11Z-16:Ac [(E6,Z11)-hexadecadienyl-1-acetate], and 6E,11Z-16:Al [(E6,Z11)-hexadecadienal]. Circular dichroism and second derivative UV-difference spectroscopy data demonstrate that the structure of subtype PBP1 significantly changes upon binding of 4E,9Z-14:Ac. The related 6E,11Z-16:Ac was less effective and 6E,11Z-16:Al showed only a small effect. In contrast, in subtype PBP2 pronounced structural changes were only induced by the 6E,11Z-16:Al, and the subtype PBP3 did not show any considerable changes in response to the pheromonal compounds. The UV-spectroscopic data suggest that histidine residues are likely to be involved in the ligand-induced structural changes of the proteins, and this notion was confirmed by site-directed mutagenesis experiments. These results demonstrate that appropriate ligands induce structural changes in PBPs and provide evidence for ligand specificity of these proteins.
Mohl
Claudia
C
University of Hohenheim, Institute of Physiology, Garbenstrasse 30, 70599 Stuttgart, Germany.
Breer
Heinz
H
Krieger
Jürgen
J
D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry* / Q000187:drug effects*; D002942:Circular Dichroism; D007301:Insect Hormones / Q000737:chemistry; D019476:Insect Proteins / Q000737:chemistry* / Q000187:drug effects*; D036341:Intercellular Signaling Peptides and Proteins; D009036:Moths; D010675:Pheromones / Q000494:pharmacology*; D011487:Protein Conformation / Q000187:drug effects; D011994:Recombinant Proteins; D013045:Species Specificity
C094731:Aper-2 protein, Antheraea pernyi; D002352:Carrier Proteins; D007301:Insect Hormones; D019476:Insect Proteins; D036341:Intercellular Signaling Peptides and Proteins; D010675:Pheromones; D011994:Recombinant Proteins; C067715:APR-1 pheromone-binding protein, Antheraea pernyi