title: Characterization of a collagenolytic serine proteinase from the Atlantic cod (Gadus morhua).
abstract: A collagenolytic proteinase was purified from the intestines of Atlantic cod by (NH4)2SO4 fractionation, hydrophobic interaction chromatography (phenyl-Sepharose) and ion-exchange chromatography (DEAE-Sepharose). 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-Phe-p-nitroanilide (sAAPFpna), an amide substrate of chymotrypsin, as well as succinyl-L-Ala-L-Ala-L-Pro-L-Leu-p-nitroanilide, a reported elastase substrate, but had no detectable activity towards several other substrates of these proteinases or of trypsin. The pH optimum of the enzyme was between pH 8.0 and 9.5 and it was unstable at pH values below 7. Maximal activity of the enzyme when assayed against sAAPFpna was centered between 45 and 50 degrees C. Calcium binding stabilized the cod collagenase against thermal inactivation, but even in the presence of calcium, the enzyme was unstable at temperatures above 30 degrees C.
authors.affiliation: Department of Chemistry, University of Iceland, Reykjavík.
authors.forename: M M
authors.initials: MM
authors.lastname: Kristjánsson
authors.forename: S
authors.initials: S
authors.lastname: Guthmundsdóttir
authors.forename: J W
authors.initials: JW
authors.lastname: Fox
authors.forename: J B
authors.initials: JB
authors.lastname: Bjarnason
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003094:Collagen / Q000378:metabolism*; D004795:Enzyme Stability; D005399:Fishes / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D012697:Serine Endopeptidases / Q000302:isolation & purification / Q000378:metabolism*; D015842:Serine Proteinase Inhibitors; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D015842:Serine Proteinase Inhibitors; D003094:Collagen; D012697:Serine Endopeptidases