Fig. 1: Multivalent peptide architectures, FPS setup and PPI mapping.
From: Multivalent binding kinetics resolved by fluorescence proximity sensing
a Architecture of multimeric geph-binding peptides. An (Fmoc)-L-Lys(Fmoc) building block facilitated multimerization of geph-binding epitopes, linked together by PEG moieties (o1-3), yielding dimeric, tetrameric and octameric peptides. b schematic representation of FPS measurements. The receptor-binding domain of the neuronal scaffolding protein gephyrin (gephE) is immobilized on the ligand strand via an NHS coupling. The binding of unmodified, multimeric peptides during the association phase is detected by a change in fluorescence of green dye b. Note that a real-time reference on spot 2 is used to control for unspecific binding or influence on the fluorophore (c) Real-time affinity determination of overlapping, dimeric GlyR β derived peptides in FPS. Peptides were used at a concentration of 1 µM. Note that only peptides with a centred FSIVG core binding motif exhibited a measurable affinity.
