Figure 3.

1-NPN binds to HvirPBP2 and is displaced by Z11-16:Ald. (A) Relative fluorescence intensity as a function of 1-NPN concentration. HvirPBP2 in Ringer solution (2 μM) was titrated with increasing amounts of 1-NPN to a final concentration of 10 μM. (B) Competitive fluorescence binding assay on HvirPBP2 (2 μM in Ringer solution) using 1-NPN (2 μM). Maximum emission of 1-NPN fluorescence was monitored after increasing concentrations of Z11-16:Ald (0–10 μM) were added. Fluorescence intensities at different pheromone component concentrations are shown as percentages of the maximum 1-NPN fluorescence in the absence of the pheromone component. Data represent the mean of three independent measurements. Standard deviations are indicated by error bars.