Figure 3.

Binding of COMP to peptide 5 and the dependency of Zn²⁺. Peptide 5 of the collagen II foldon library was coated to an ELISA plate and incubated with COMP protein (a) or with COMP in interaction buffer containing indicated chemical compounds (b). Binding was detected with a specific anti-COMP antibody. Bars indicate standard deviation of triplicates. The peptide sequence is depicted in Table 1. The calculated K_D for the pep5 interaction in (a) is 19.3 ± 12.4 nM. (c) The radius of particles (obtained by cumulant analysis) measured of a COMP solution with addition of the indicated ZnCl ions were monitored over time using dynamic light scattering. Phe: 1,10-phenanthroline.