동양배 Protease의 精製 및 性質에 關하여

다국어 초록 (Multilingual Abstract)

These studies were conducted to investigate the extraction, purification and characterization of oriental pear protease, and the results obtained were as follows:
1. Oriental pear protease was effectively extracted by the method of homogenizing pear pulp with 0.7 volumes of 0.1 M - Sodium phosphate buffer, pH 6.5 containing 5mM - cysteine, 40mM - 2 - mercaptoethanol and 2mM - EDTA at 10,000 rpm for 5 min.
2. The protease was purified by ammonium sulfate fractionation, Sephadex G-100 filtration and DEAE-Sephadex A-50 column chromatography, and the purified enzyme gave a single protein band on polyacrylamide gel electrophoresis.
3. The specific activity of purified enzyme was 29.65 units/mg protein and the yield was 7.22 %.
4. The molecular weight of the protease was estimated to be about 51,000 by SDS-polyacrylamide gel electrophoresis, and the enzyme had Km value of 54.5mg/ml for casein.
5. The purified enzyme has a maximum activity at pH6.0 and 50 ℃, and was stable from pH 5.5 - 6.5 and at temperatures below 50 ℃.
6. Casein was a better substrate for this protease compared to hemoglobin.
7. The enzyme activity was markedly inhibited by p-chloromercuribenzoic acid and heavy metal salts such as HgCl₂ and MnSO₄ also considerably inhibited the enzyme activity.

목차 (Table of Contents)

• 목차
• I. 서론 = 1
• II. 재료 및 방법 = 2
• 1. 재료 = 2
• 2. 방법 = 2
• 1) 조 효소액의 조제 = 2
• 2) Protease 활성의 측정 = 3
• 3) 추출조건의 검토 = 3
• 4) 효소의 정제 = 4
• 5) 효소학적 성질의 검토 = 5
• III. 결과 및 고찰 = 10
• 1. 추출조건 = 10
• 2. 효소의 정제 = 19
• 3. 효소학적 성질 = 24
• IV. 결론 = 36
• References = 38
• Summary = 40