Fig. 4

Chymotrypsin digest of recombinant type II human procollagen. Alexa 647-labelled procollagen was incubated with different concentrations of chymotrypsin for 30 min at 4 °C. Increasing concentrations led to successful removal of the propeptides, while leaving the triple helix intact, as evidenced by the collapse of all signal into a unique, high-MW band following incubation with 31.2 μg/ml chymotrypsin. a Fluorescence scan of the gel, showing all protein in the sample. b Western blot with a monoclonal antibody to the N-telopeptide. This Western shows that the high-MW signal is due to collagen, and furthermore demonstrates that only at the highest concentration is the telopeptide epitope removed