Figure 5
From: Male tarsi specific odorant-binding proteins in the diving beetle Cybister japonicus sharp
Affinity of CjapOBPs to candidate chemical ligands.
(A) Both CjapOBP1 and CjapOBP2 bind the fluorescent probe 1-NPN, with dissociation constants of 3.3 μM and 2.1 μM, respectively. (B) Competitive binding curves of selected ligands to the two CjapOBPs. Mixtures of proteins (5 μM) and 1-NPN (2 μM) were titrated with 1mM solutions of the ligands in methanol. Among the ligands tested, CjapOBP1 shows good affinity only to citral and CjapOBP2 bind coniferyl aldehyde strongly, but not dihydroferulic acid, eugenol and α-methoxycinnamaldehyde, which are structurally related to coniferyl aldehyde. (C) The chemical structures of the chemicals applied.
