Mm. Kristjansson et al., CHARACTERIZATION OF A COLLAGENOLYTIC SERINE PROTEINASE FROM THE ATLANTIC COD (GADUS-MORHUA), Comparative biochemistry and physiology. B. Comparative biochemistry, 110(4), 1995, pp. 707-717
A collagenolytic proteinase was purified from the intestines of Atlant
ic cod by (NH4)(2)SO4 fractionation, hydrophobic interaction chromatog
raphy (phenyl-Sepharose) and ion-exchange chromatography (DEAE-Sepharo
se). The proteinase has an estimated molecular weight of 24.1 (+/-0.5)
kDa as determined by SDS-PAGE and belongs to the chymotrypsin family
of serine proteinases, The enzyme cleaves native collagen types I, III
, IV and V, and also readily hydrolyzes succinyl-L-Ala-L-Ala-L-Pro-L-P
he-p-nitroanilide (sAAPFpna), an amide substrate of chymotrypsin, as w
ell as succinyl-L-Ala-L-Ala-L-Pro-L-Leu-p-nitroanilide, a reported ela
stase substrate, but had no detectable activity towards several other
substrates of these proteinases or of trypsin, The pH optimum of the e
nzyme was between pH 8.0 and 9.5 and it was unstable at pH values belo
w 7. Maximal activity of the enzyme when assayed against sAAPFpna was
centered between 45 and 50 degrees C. Calcium binding stabilized the c
od collagenase against thermal inactivation, but even in the presence
of calcium, the enzyme was unstable at temperatures above 30 degrees C
.