Partial Purification and Characterization of a Heat Stable α-Amylase from a Thermophilic Actinobacteria, Streptomyces sp. MSC702.
Partial Purification and Characterization of a Heat Stable α-Amylase from a Thermophilic Actinobacteria, Streptomyces sp. MSC702.
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DOI：
10.1155/2014/106363
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Kapoor V
中科院分区：
文献类型：
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作者：
Singh R;Kumar V;Kapoor V
对链霉菌MSC 702的α-淀粉酶进行了部分纯化和生化特性研究。对该菌株淀粉分解酶的最适底物反应条件进行了研究。测定该酶的最适pH、温度和孵育时间分别为5.0、55°C和30 min。使用硫酸铵沉淀浓缩细胞外提取物。它在金属离子（5 mM）如K+、Co 2+和Mo 2+的存在下是稳定的，而Pb 2+、Mn 2+、Mg 2+、Cu 2+、Zn 2+、Ba 2+、Ca 2+、Hg 2+、Sn 2+、Cr 3+、Al 3+、Ag+和Fe 2+被发现具有抑制作用。在1%Triton X-100、1%Tween 80、5 mM十二烷基硫酸钠、1%甘油、5 mM EDTA和5 mM变性剂尿素存在下，酶活性也不稳定。在温度60°C和pH 5.0时，酶的稳定性最高。α-淀粉酶在60°C（pH 7.0）下保持100%和34.18%的稳定性分别为1小时和4小时。该酶在60°C温度下表现出195分钟的半衰期。动力学分析表明，该酶对马铃薯可溶性淀粉的Km为2.4mg/mL，Vmax为21853.0 μmol/min/mg。结果表明，该酶具有工业应用的潜力。
A partial purification and biochemical characterization of the α-amylase from Streptomyces sp. MSC702 were carried out in this study. The optimum operational conditions for enzyme substrate reaction for amylolytic enzyme activity from the strain were evaluated. The optimum pH, temperature, and incubation period for assaying the enzyme were observed to be 5.0, 55°C, and 30 min, respectively. The extracellular extract was concentrated using ammonium sulfate precipitation. It was stable in the presence of metal ions (5 mM) such as K+, Co2+, and Mo2+, whereas Pb2+, Mn2+, Mg2+, Cu2+, Zn2+, Ba2+, Ca2+, Hg2+, Sn2+, Cr3+, Al3+, Ag+, and Fe2+ were found to have inhibitory effects. The enzyme activity was also unstable in the presence of 1% Triton X-100, 1% Tween 80, 5 mM sodium lauryl sulphate, 1% glycerol, 5 mM EDTA, and 5 mM denaturant urea. At temperature 60°C and pH 5.0, the enzyme stability was maximum. α-amylase retained 100% and 34.18% stability for 1 h and 4 h, respectively, at 60°C (pH 7.0). The enzyme exhibited a half-life of 195 min at 60°C temperature. The analysis of kinetic showed that the enzyme has K m of 2.4 mg/mL and V max of 21853.0 μmol/min/mg for soluble potato starch. The results indicate that the enzyme reflects their potentiality towards industrial utilization.