초록
Ganoderma lucidum (영지)의 액체 배양물로부터 전분을 강력하게 분해하는 amylase를 조정제하여 이 효소의 기본적인 성질을 조사하였다. 이 효소의 최적작용 pH와 온도는 각각 5.5, 5$0^{\circ}C$였고 pH 및 열처리에 상당히 불안정한 효소였으며 activation energy는 7.06Kcal/mole이였다. M $n^{++}$, $Ca^{++}$ 및 C $u^{++}$에 의해서 효소활성이 증가되었으나 H $g^{++}$ A $g^{+}$에 의해서 효소활성이 저해되었으며 여러 가지 chemical reagents에 의해서는 영향을 받지 않았다. Soluble starch, amylose, amylopectin 및 glycogen에 대한 Km 치는 0.16, 0.37, 0.19 및 0.16mg/$m\ell$ 였으며 각종기질에 대한 분해능력을 조사한 결과 열처리를 받은 전분류는 분해할 수 있었으나 생전분은 그 분해속도가 느렸다. Maltose에 의해서 효소활성이 저해되었으며 maltose의 저해양상은 competitive inhibition을 나타내었다.
Extracellular amylase from tile filtrate of the submerged culture of Ganoderma lucidum was partially purified by ammonium sulfate precipitation and its properties were studied. The optimum pH and temperature of the enzyme activity were 5.5 and 5$0^{\circ}C$. respectively. This enzyme was most stable at pH 5.0 and stable up to 3$0^{\circ}C$, but it lost completely the activity when it was treated at 6$0^{\circ}C$ for 10 min. The enzyme was activated by the addition of M $n^{++}$, $C^{++}$ and C $u^{++}$, but inhibited by H $g^{++}$, A $g^{++}$ And various enzyme inhibitors and chemical reagents did not affect the enzyme activity. The enzyme hydrolyzed the boiled amylaceous polysaccharides, but it hydrolyzed raw starches very slowly. The activation energy of the enzyme for soluble starch was calculated and found to be 7.06 Kcal per mole. The Km values of the enzyme for soluble starch, amylose, amylopectin and glycogen were 0.16, 0.37, 0.19, and 0.16mg/$m\ell$, respectively. Maltose was found to inhibit the enzyme activity and kinetic analysis revealed a competitive type of inhibition.n.n.n.n.n.