밀단백질중의 β-Amylase의 性狀에 관한 연구 = Studies on Physicochemical Properties of Wheat β-Amylase

국문 초록 (Abstract)

정제된 밀 β-amylase F-A 및 F-C의 단백질 화학적 및 효소 화학적 특성을 검토하였다. 정제 효소는 F-A, F-C 모두 SDS 전기영동 결과 분자량 54,500, 등전점은 F-A가 4.96, F-C가 4.61이고 아미노酸 殘基數는 F-A가 효소 1mole당 약 522잔기, F-C가 약 526잔기이다. ??, ?? 이온은 효소 F-A, F-C의 活性을 增加시켰으나 ??, ??, ??, ??이온은 효소 활성을 저해하였다. 작용 최적 pH는 F-A, F-C 모두 6.0이였다. 안정 pH영역은 pH4.5에서 7.5까지이고 작용 최적온도는 F-A, F-C 모두 50℃이며 안정온도 범위는 60℃이하로 나타났다. Km값은 가용성 전분에 대해 F-A가 0.19%, F-C가 0.56%로 나타났다.

다국어 초록 (Multilingual Abstract)

Beta-amylase(β-1, 4-D-glucan maltohydrolase, E. C. 3. 2. 1. 2.) from wheat (triticum aestivum var. Gerumil) produced in Korea was purified.
The homogenity of purified wheat beta-amylase was indentified by P A G E. Enzymatic physico-chemical properties of the beta-amylase were investigated. The results thus obtains were as follows.
The molecular weight of wheat beta-amylase determined by the S D S electrophoresis was 54,500 daltons. Isoelectric point of wheat beta-amylase for Fraction A and C were 4.96 and 4.61, respectively.
Amino acid residues of wheat beta-amylase Fraction A and C were estimated to be around 522 and 526 per mol of enzyme, respectively. Wheat beta-amylase activity was increased by Ca?? and Mg?? ions, while it was inhibited by Hg??, Cu??, Ag??? and Fe??? ions. Km values of wheat beta-amylase Fraction A and C for soluble starch were 0.19 and 0.56%, respectively. The optimum pH and temperature of wheat beta-amylase Fraction A and C were 6.0 and 55℃. The enzyme were stable at pH 4.5 through 7.5 at below 50℃.