ペプシンの酵素的性質 (カツオペプシンに関する研究-1,2-)

概要

論文の詳細を見る
In the present paper, some enzymic properties of the bonito pepsin, purified by ammonium sulfate fractionation as described in the previous paper, were determined by comparison with the crystalline hog pepsin. The results obtained are as follows: 1. Effect of pH on PU (proteolytic activity). The optimum pH values of bonito pepsin were near 2 for the substrate of milk casein and hemoglobin and another optimum value was observed at near 3.6. Hog pepsin had optimum pH values of 1.6 for casein and 2.0 for hemoglobin. 2. Effect of substrate concentration on PU. Bonito and hog pepsins showed maximum activity in hemoglobin concentrations of 1.5-2.5%, and 0.7% (W/V), respectively. 3. Effect of reaction temperature on PU. These optimum temperatures for bonito and hog pepsins were 35°C and 45°C, respectively. 4. Stability. Considerable differences regarding thermal stability were not observed for both pepsins, but in a neutral solution hog pepsin was rather less stable than the bonito pepsin. 5. Substrate specificity. Pepsins of both bonito and hog exhibited proteolytic action on hemoglobin, but the former pepsin was less active than the latter for the synthetic substrate (N-acetyl-l-phenylalanyl-l-diiodotyrosine). As conclusion, species specificity between the pepsins of bonito and hog can be detected in some enzymic properties.
社団法人日本水産学会の論文