魚類幽門垂プロティナーゼに関する研究-II
精製サバ幽門垂プロティナーゼの諸性質について
1971 年 37 巻 2 号 p. 145-148
詳細
1971 年 37 巻 2 号 p. 145-148
Previously, the author reported on the purification results of proteinase from the pyloric caeca of mackerel by extraction with water, ammonium sulfate fractionation, DEAE-cellulose column chromatography and Sephadex gel filtration.
In this paper, studies on some of the properties of this purified proteinase are reported. The purified mackerel proteinase has been ascertained to be most active at pH 9.0 and 43°C, with casein as substrate.
And this proteinase hydrolysed no less than 70% of the peptide bond in casein; while crystalline bovine trypsin was hydrolysed only 15%.
Therefore, mackerel proteinase differs also in this respect from the bovine trypsin, although the optimum pH and temperature of these two enzymes are almost similar.
The purified proteinase appeared homogeneous on electrophoretic analysis. Finally, by gel filtration on Sephadex G-200 the elution volume of mackerel proteinase was determined and compared with those of other proteins of known molecular weight. From the elution volume the molecular weight of mackerel proteinase has been estimated to be 30, 000.
