Fig. 8.

(A) GEE labeling extents of OCP^r amino-acid residues in the presence or absence of FRP. (B) GEE labeling level of OCP^o amino acid residues in the presence or absence of FRP. $\text{GEE labeling level}=\frac{\text{Peak area of labled peptide}}{\text{Peak area of labled peptide}+\text{Peak area of unlabled peptide}}$ (C) A bar graph showing the changes in OCP mono-links in the presence FRP. $\mathrm{R}=\frac{\text{Abudance of monolink upon interacting with FRP}}{\text{Abudance of monolink for OCP only sample}}$ (D) An isotope-encoded mass spectrum of crosslinked OCP-FRP showing the K167(OCP)-M1(FRP) cross-link in the orange state is less abundant than in the red state.