Gh. Peng et Ws. Leal, Identification and cloning of a pheromone-binding protein from the oriental beetle, Exomala orientalis, J CHEM ECOL, 27(11), 2001, pp. 2183-2192
We have identified and cloned a pheromone-binding protein (EoriPBP) from th
e Japanese and American populations of the Oriental beetle, Exomala orienta
lis (Coleoptera: Scarabaeidae). The protein showed more than 90% amino acid
identity to the previously identified pheromone-binding proteins from Popi
llia japonica (PjapPBP) and Anomala osakana (AosaPBP), as well as to one of
the odorant-binding proteins from Phyllopertha diversa (PdivOBP1). EoriPBP
has 116 amino acids, with a calculated molecular mass of 12,981 Da, pI of
4.3, and six highly conserved cysteine residues. 5'-RACE amplifications led
to the characterization of a signal peptide with 19 amino acids. The signa
l peptide showed high amino acid identity to the signal peptide for AosaPBP
. Comparison of the amino acid sequences of the PBPs involved in the detect
ion of similar ligands, i.e., monounsaturated lactones and ketone, suggests
that the most variable residues among the PBPs from E. orientalis, P. japo
nica, and A. osakana are probably the most discriminating residues. As with
the pheromone-binding protein from Bombyx mori, the residues at positions
61, 64, 71, and 82 in EoriPBP, PajpPBP, and AosaPBP, which are either valin
e, leucine, isoleucine, or methionine, are likely to be specificity determi
nants.