Correlation between pronase susceptibility and hydroxy proline content of collagen fiber

Abstract

1. 1.|The solubilization rates of various collagen fibers by pronase were compared. Hydroxyproline-poor collagens (Ascaris cuticle and cod skin) were found to be more susceptible to pronase action than hydroxyproline-rich collagens (rat tail tendon and earthworm cuticle). 2. 2.|The rates of the digestion of the soluble collagens from rat and Ascaris were of the same order of magnitude in contrast to the solubilization rates of the fibers. 3. 3.|The fiber of rat collagen became susceptible to pronase when incubated in 2 M urea. 4. 4.|These results suggest that the hydroxyl group of hydroxyproline in collagen would make the fiber rigid by participating in hydrogen bond formation between the tropocollagen molecules and interfere with the access of the proteolytic enzyme.