논문 상세보기
pp.119-123
토양 시료로부터 dextran을 강하게 분해하는 Aspergillus sp. BY-54 균주는 분리 선별하고 이 균을 이용하여 dextranase 생성 최적 조건을 검토하였으며 또한 이 효소를 조정제하고 효소학적 특성을 조사한 결과는 다음과 같다. 탄소원으로서 dextran의 최적농도는 1%이었으며, 효소생성 최적 온도는 30℃, 그리고 효소생성에 미치는 초발 pH는 7로 나타났다. Aspergillus sp. BY-54가 생성하는 dextranase를 DEAE-cellulose column chromatography 법으로 2단계 NaCl농도 구배로 용출함으로서 조정제하였다. Dextranase의 K_m은 0.222%이었으며 glucosidic linkage를 한 DEAE-sephadex, CM-sephadex 및 sephadex G-100을 기질로 하였을 때도 dextran을 기질로 한 경우와 비슷한 활성을 보였으며, 저해제로서 sodium fluoride, KMnO_4 및 p-CMB등은 본 효소를 강하게 저해하였다. KCN은 오히려 본 효소를 20%정도로 활성화시켰다.
Aspergillus sp. BY-54 which produced a strong dextran hydrolyzing enzyme was isolated from soil. Using this strain, the optimal cultural conditions, enzyme purification and characterization were studied. The results are as follows : The optimal concentration of dextran as carbon source was 1%. and the optimum temperature and the initial pH for enzyme production was 30℃, and 7.0, respectively. Dextranase was purified by DEAE-cellulose column chromatography with a linear gradient increase in NaCl. K_m value of dextranase was 0.222%, and several glucans containing various types of glucosidic linkages such as DEAE-sephadex, CM-sephadex and sephadex G-100 were almost digested to a large extent with this dextranase. The enzyme was strongly inhibited by sodium fluoride, KMnO_4 and p-CMB, while KCN caused 20% of activation.
