Phosphorylation Alters the Interaction of the Arabidopsis Phosphotransfer Protein AHP1 with Its Sensor Kinase ETR1
Measurements were done in the presence of 100 µM ethephon (•) or 100 µM potassium cyanide (○). In a control experiment (▴) the cofactor copper essential for ethylene binding was omitted. The dashed grey curve (—) represents a fit to these data according to Equation 2 corresponding to a dissociation constant of 1.4 µM . Binding curves fitted to the experimental data obtained in the presence of ethephon (——) or in the presence of cyanide (——) correspond to dissociation constants of 7.7 µM and 9 µM, respectively.