Probing the formation of a parallel heterodimeric coiled coil by fluorescence quenching

Engineered leucine zipper peptides that are unfolded in isolation were appended at the N-terminus with the 2-aminobenzoyl probe or the 2,4-dinitrophenyl-β-alanine amino acid. The intrinsic fluorescence of the 2-aminobenzoyl group is quenched when the peptides associate in benign medium to form a parallel heterodimeric coiled coil.