低温淀粉酶菌株C2的分离鉴定及其产低温淀粉酶的酶学性质

Screening and identification of cold-active amylase strain C2 and its amylase characterization

获得低温淀粉酶高产菌株,确定该菌株所产淀粉酶的酶学性质。从大黑山(大连)污泥中筛选菌株,通过菌株的形态特征、生理生化和16S rDNA序列鉴定确定其种属,对其酶学性质进行初步研究。获得1株低温淀粉酶高产菌株C2,经鉴定其为微小杆菌属,C2所产低温淀粉酶最适反应温度为25°C,酶的热稳定性比较差,最适pH为7.5,Ca2+和Fe2+对该酶有激活作用,Cu2+、Ni2+、Go2+等抑制酶活性。经薄层层析(TLC)鉴定酶解产物为葡萄糖,说明该菌株具有产生低温淀粉糖化酶的能力。菌株C2所产淀粉酶符合低温淀粉酶性质,值得进一步研究。

Strain producing cold-active amylase want to be isolated. Enzymatic properties of the strain will be determined. Screening strains from The Black mountant. Determine its species by its morphological, the physiological and biochemical properties and 16S rDNA sequence analysis, to study its enzymatic properties. A strain C2 producing cold-active amylase was identified as Exiguobacterium sp.. Enzymatic properties showed that the optimum pH value is 7.5 and the optimum reaction temperature is 25 ℃, but the thermal stability of the enzyme is relatively poor. The amylase activity was activated by Ca2＋ and Fe2＋, and was inhibited by Cu2＋, Ni2＋ and Go2＋. By the identification of TLC, the product of enzymolysis is glucose. It is indicates that the strain can product cold-active starch glucoamylase. Amylase produced by strain C2 in line with the nature of cold-active amylase, it deserves to be further researched.