Hydrolysis of collagen molecules in the presence of collagenolytic pro
teases A and C from the king crab has been studied by electrophoresis.
Both proteases are shown to hydrolyze effectively type I and III coll
agens, patterns of the products differing for the proteases A and C. T
he thermal denaturation of the type I collagen increased the effective
ness of the enzymatic hydrolysis. The crab collagenolytic proteases ca
talyze the hydrolysis of such proteins as bovine serum albumin, ovalbu
min, horse cytochrome c, mouse immunoglobulin G, casein and human fibr
inogen, only elastin being resistant. The mechanisms of the fibrinogen
cleavage differ not only for the proteases A and C but also for plasm
in, whereas the efficiencies in all the cases are similar.