Figure 2
(A) Fractionation of a crude extract of trunk wash from the African elephant by anion-exchange chromatography. SDS-PAGE analysis of the fractions showing electrophoretic bands in the low molecular weight range (15–25 kDa). (B) Summary of the affinities to (Z)-7-dodecenyl acetate, (E)-β-farnesene and frontalin measured with crude samples of the same fractions. All of them bound with good affinity both (Z)-7-dodecenyl acetate and (E)-β-farnesene. Also farnesol, proved to be as good a ligand as (E)-β-farnesene, whereas exo-brevicomin did not show any affinity. Dissociation constants were evaluated using the procedure adopted when dealing with solutions of a pure protein; as this is not the case, the values have to be taken as a crude indication of the affinity of the ligands for the protein. (C) Examples of the competition curves measured with the three ligands on fraction 27.
