Department of Microbiology, University of Nigeria, Nsukka, Nigeria.
Appl Environ Microbiol. 1984 Mar;47(3):571-5. doi: 10.1128/aem.47.3.571-575.1984.
A thermostable amylase, possibly a beta-amylase from Thermoactinomyces sp. no. 2 isolated from soil, is reported. The enzyme was purified 36-fold by acetone precipitation, ion-exchange chromatography, and Sephadex G-200 gel filtration, and the molecular weight was estimated at 31,600. The enzyme was characterized by demonstration of optimum activity at 60 degrees C and pH 7 and by retention of 70% activity at 70 degrees C (30 min). It was stimulated by Mn and Fe but strongly inhibited by Hg. Maltose was the only detectable product of hydrolysis of starches and was quantitatively highest in plantain starch hydrolysate.
报道了一种耐热淀粉酶，可能是从土壤中分离到的嗜热放线菌 No.2 中的β-淀粉酶。该酶通过丙酮沉淀、离子交换层析和 Sephadex G-200 凝胶过滤进行了 36 倍的纯化，分子量估计为 31600。该酶的特点是在 60°C 和 pH7 时表现出最佳活性，在 70°C（30 分钟）时保留 70%的活性。它被 Mn 和 Fe 激活，但被 Hg 强烈抑制。麦芽糖是淀粉水解的唯一可检测产物，在芭蕉淀粉水解物中的含量最高。
