α-1 , 4-D-Glucan phosphorylase of gram-positive Corynebacterium callunae : isolation , biochemical properties and molecular shape of the enzyme from solution X-ray scattering
α-1 , 4-D-Glucan phosphorylase of gram-positive Corynebacterium callunae : isolation , biochemical properties and molecular shape of the enzyme from solution X-ray scattering
复制标题
革兰氏阳性棒状杆菌的 α-1, 4-D-葡聚糖磷酸化酶：从溶液 X 射线散射中分离、生化特性和酶的分子形状
DOI：
--
复制
发表时间：
1997
期刊：
影响因子：
--
通讯作者：
B. Nidetzky
中科院分区：
文献类型：
--
作者：
Andreas Weinha;Usel;R. Griessler;A. Krebs;P. Zipper;D. Haltrich;K. D. Kulbe;B. Nidetzky
从革兰氏阳性愈伤棒状杆菌中分离并鉴定了α-1,4--葡聚糖磷酸化酶。这种酶差不多是可诱导的。被麦芽糖抑制2倍，但明显不被-葡萄糖抑制。磷酸化酶是一种同型二聚体，每88-kDa蛋白亚基的辅因子吡哆醛5 -磷酸的化学计量学含量。利用葡聚糖合成和降解方向上的特异性常数（k cat} k m，葡聚糖）将该酶分类为第一个细菌淀粉磷酸化酶。大底物对小底物的偏好是由表观结合常数的变化而不是催化中心活性决定的。的贡献
The α-1,4--glucan phosphorylase from gram-positive Corynebacterium callunae has been isolated and characterized. The enzyme is inducible approx. 2-fold by maltose, but remarkably not repressed by -glucose. The phosphorylase is a homodimer with a stoichiometric content of the cofactor pyridoxal 5«phosphate per 88-kDa protein subunit. The specificity constants (k cat }K m,glucan ) in the directions of glucan synthesis and degradation are used for the classification of the enzyme as the first bacterial starch phosphorylase. A preference for large over small substrates is determined by variations in the apparent binding constants rather than catalytic-centre activities. The contribution