Some Characteristics of the Enzymes of the Pyloric Caeca of Cod and Haddock

Abstract

Investigation of fish enzymes for leather bates reveals that those of the pyloric caeca show their greatest influence on casein and collagen at hydrogen ion concentrations of approximately pH 8. The protease showed its maximum activity towards casein at a temperature of 45"C. Ammonium salts at certain concentrations increased the rate of hydrolysis of collagen by about 40 per cent, but had no like stimulating effect on the hydrolysis of casein. A comparison showed that pyloric caeca enzymes were just .as satisfactory as commercial leather bates or hog pancreas. When the pyloric caeca are allowed to autolyse at room temperature, the protease activity is constant for the first 24 hours, declines rapidly during the next 80 hours, and slowly thereafter. The most suitable method for preparing a dried preparation was by evaporation under partial vacuum, which, however, is accompanied by some loss of activity. This paper describes certain work which has been carried out on the enzymes of the pyloric caeca of cod and haddock with the object of furnishing other laboratories with data to enable them to assess the value of such material in leather bating.This examination was undertaken on the suggestion Among others a bate must possess the property of digesting certain skin con-J. Biol. Board Can. Downloaded from www.nrcresearchpress.com by ACQ Service/Serials (A) on 02/03/15For personal use only.

Purification and characterization of trypsin from the poikilotherm Gadus morhua

“…8OC. Earlier studies have shown the presence of trypsin, or a trypsin-like enzyme, in this fish species, but the enzyme was neither fully purified nor characterized kinetically with respect to temperature dependence [9,101. Trypsin or trypsin-like enzymes have been characterized from other fishes [ll -131, including two arctic species, the capelin [14] and Greenland cod [15, 161. The present report describes the results obtained from studies on trypsin isolated from the pyloric caeca of Atlantic cod, the site of exocrine pancreatic tissue in the cod [17].…”