Calculated Kds and derived ΔG° (Gibbs free energy of binding) for the interactions between eIF4E and the N-Cap derivative peptides.

The table shows the peptide sequences used to study the influence of alternative residues and their effects in capping the first turn of the α-helix when bound to eIF4E. Kds were determined using SPR with eIF4E immobilized on the chip surface. Kds were derived from the equilibrium responses (Keq) and from the association and dissociation phases (Kkin) of the SPR data. The Gibbs free energy of binding (ΔG°) was calculated with the equation ΔG = –RT ln Ka using both dissociation constant values determined.