来自酵母科诺宁科酵母的一种具有中等热稳定性的新型α-淀粉酶的纯化与表征

Purification and characterization of a new alpha-amylase of intermediate thermal stability from the yeast Lipomyces kononenkoae.

作者信息

Prieto J A, Bort B R, Martínez J, Randez-Gil F, Buesa C, Sanz P

机构信息

Deptamento Bioquímica, Facultad de Farmacia, Universidad de Barcelona, Spain.

出版信息

Biochem Cell Biol. 1995 Jan-Feb;73(1-2):41-9. doi: 10.1139/o95-005.

DOI:10.1139/o95-005

PMID:7662314

Abstract

A new alpha-amylase from the extracellular culture of the yeast Lipomyces kononenkoae CBS 5608 has been purified to homogeneity by ammonium sulphate treatment, affinity binding on cross-linked starch, and DEAE-Biogel A chromatography. The enzyme was monomeric, with an apparent M(r) of 76 kilodaltons, pI < 3.5, and optimum pH 4.5-5.0, and exhibited intermediate thermal stability. The temperature for optimal enzyme activity was 70 degrees C. It is a glycoprotein with both N- and O-linked sugars. Kinetic analyses indicate that the enzyme has an endoamylolytic mechanism. The kM for soluble starch was 0.80 g.L-1 and the kcat was 622.s-1.

摘要

一种来自酵母科诺宁科酵母CBS 5608细胞外培养物的新型α-淀粉酶，通过硫酸铵处理、交联淀粉上的亲和结合以及DEAE-琼脂糖凝胶A柱色谱法纯化至均一。该酶为单体，表观分子量为76千道尔顿，等电点小于3.5，最适pH为4.5 - 5.0，具有中等热稳定性。酶的最佳活性温度为70℃。它是一种同时含有N-连接和O-连接糖的糖蛋白。动力学分析表明该酶具有内切淀粉酶作用机制。可溶性淀粉的米氏常数为0.80 g·L⁻¹，催化常数为622 s⁻¹。