The pulling of Lys39 upwards impinges upon helix B and its orientation relative to helix A and the hydrophobic patch that the switch peptide binds to, manifested as the change in interhelical angle. Longer range allosteric consequences of the helix B rearrangement include a repositioning of the switch peptide and changes in the peptides crossing the interdomain interface that can account for the observed changes in hinge angle.