Abstract
The $(NH_4)_2\;SO_4$ (70%) treated crude enzymes from the culture filtrates of the$C-7^{+t}$ strain of Pyricularia oryzae which was grown on 2% CMC (carboxymethyl cellulose) for 8 days at $28^{\circ}C$ were chromatographied on Sephadex G-150 and DEAE-Sephadex A-25 columns. From the chromatography, three fractions of CMCase$(C_x)$ was examined using Na-CMC as substrate. The $C_x$ enzyme activity was optimal at pH 6.0 and $40^{\circ}C$, stable up to $40^{\circ}C$. The values of Km and Vmax of the enzyme were $2.8{\times}10\;mM$ and 5.9m moles/hour, respectively. The molecular weight determined by Sephadex G-150 column chromatography was around 80,000. Approximately sevenfold purified $C_x$ enzyme gave a single protein band on the polyacrylamide gel electrophoresis.
2% CMC (Carboxymethyl cellulose)를 탄소원으로 하여 $28^{\circ}C$에서 8일간 배양한 도열병균 (Pyriculariaoryzae, $C-7^{+t}$)의 배양액을$(NH_4)_2SO_4$ 염석, Sephadex G-150 및 DEAE-Sephadex A-25 column chromatography를 거쳐 순화하였다. 순화결과 $F_1,\;F_2,\;F_3$ 3개의 CMCase $(C_x)$, 1개의 Avicelase $(C_1)$ 및 1개의 ${\beta}-glucosidase$를 얻었는데 그중 $C_1$ 효소의 $F_3$만을 골라 실험을 계속했다. 이 효소의 활성도는 pH 6.0 과 $40^{\circ}C$에서 가장 높았으며 $40^{\circ}C$까지 안정한 효소인 것을 알 수 있었다. 이 효소의 Km과 Vmax값은 각각 $2.8{\times}10^{-3}mM$, 5.9 mmoles/hour이었고, 분자량은 Sephadex G-150 column chromatography에 의해 약 80,000으로 나타났다. 약 7배로 순화된 이 효소의 순화정도를 polyacrylamide gel electrophoresis에 의해 검증한 결과 1개의band를 나타냈다.