摘要
用硫酸铵分级沉淀,凝胶过滤色谱,离子交换色谱等分离技术,对黑曲霉(Asper gillusniger)β-葡萄糖甙酶进行分离纯化,共得到4种酶组分(Ⅰ-la、Ⅰ-b、Ⅰ-lc、Ⅲb),经凝胶电泳鉴定均为单一带,Ⅰ-la、Ⅰ-lb、Ⅰ-lc、Ⅲb的最适pH分别为5.0、5.5、5.0、5.5,均在pH2.0～7.0之间稳定,最适温度分别为65、55、60、50℃;保温1h时的半失活温度t(1/2)分别为68、58、61、52℃,SDS-凝胶电泳法测得Ⅰ-la、Ⅰ-lb、Ⅰ-lc、Ⅲb的分子量分别为77000、67000、73000、43000,聚丙烯酰胺等电聚焦法测得四者的等电点分别为6.0、5.7、5.2和4.4.在所测定的化学试剂中,Ag^+、Hg^(2+)和Cu^(2+)对这4个酶组分均有较强的抑制作用,EDTA、SDS和脲对酶各组分也有明显的抑制作用。
Through systematical isolation and purification of @-glucosidase from Aspergillus niger using the technique of (NH4)2SO4 fractionation, gel filtration and ion exchange chromatography, we obtained four components of β-glucosidase (I-la,I-lb,I-lc, Ⅱb). All of them showed homogeneity in the gel electrophoresis. I-la,I-lb,I-lc, Ⅱ b showed optimal activity at pH 5. 0,5. 5 , 5. 0 . 5. 5 and 65,55,60,50 ℃ ,respectively. I-1a,I-1b,I-1c, Ⅱb were stable in the pH range 2. 0-7. 0. The temperature for loss half activity (t1/2) in 1 h were:1-1a,68℃ ;I-1b,58℃;I-1c,61 ℃; Ⅱ b,52℃. The molecular weights of I-1a,I1-1b,I-1c and I b were 77 000,67 000,73 000, and 43 000 asextimated by SDS gel electrophoresis and their isoelectric points were 6. 0,5. 7,5. 2 and 4. 4 as estimated by polyaceylamide gel isoelectric focusing. Ag+,Hg2+ and Cu2+ ions showed potent inhibitory effect on I-1a,I-1b,1-1c , Ⅱb,EDTA,SDS and Urea also showed strong inhibitory effect.
出处
《厦门大学学报（自然科学版）》
CAS
CSCD
北大核心
1992年第6期687-691,共5页
Journal of Xiamen University：Natural Science
关键词
黑曲霉
葡萄糖苷酶
提纯
Aspergillus niger,β-glucosidase, Purification and properties
