Studies on egg protein VI : The trypsin inhibitor and flavomucoid fraction of ovomucoid (Agricultural Chemistry)

Abstract

卵白から硫安分別, DEAE-C処理によってオボムコイドを純化し, CM-Cカラムクロマトグラフィーによりオボムコイドは4成分たんぱく(I∿IV)から組成されていることを明らかにした。オボムコイド4成分たんぱくのうち, I, IIにのみ抗トリプシン活性が認められ, ともにトリプシンと等モル作用して阻害することがわかり, またその活性はpH8.0において100°, 20分;90°, 30分;80°, 170分の加熱処理で完全に失活した。IIIおよびIV成分たんぱくは, フラボムコイドK_1,K_2のアポたんぱくであり, いずれもFRと等モルで結合し, その結合割合はpH7.0付近が最も高く, また結合能は80°以上の加熱では55分以内で, 70°加熱では2時間でなくなった。The ovomucoid was purified by the DEAE-C treatment after the ammonium sulfate fractionation of egg white. It is demonstrated by the CM-C column chromatography that the ovomucoid consisted of four protein components (I-IV). The antitryptic activity was present only in components I and II, and both components inhibit trypsin by forming the equimolar complexes. The antitryptic activity was inactivated completely by the heating at 100℃ for 20 minutes, at 90℃ for 30 minutes and 80℃ for 170 minutes at pH8.0. The components III and IV are the apoprotein of falvomucoid K_1 and K_2; both components bind flavin to form the equimolar complex. The optimum pH for FR-binding was 7.0 and the flavin-binding capacity was inactivated by heating for 55 minutes at 80℃ and also 2 hours of heating at 70℃

    Similar works