Cho M J, Cha S S, Park J H, Cha H J, Lee H S, Park K H, Oh B H
Department of Life Sciences and School of Environmental Engineering, Pohang University of Science and Technology, Hyoja-dong, San 31, Pohang, Kyungbuk 790-784, Korea.
Acta Crystallogr D Biol Crystallogr. 1998 May 1;54(Pt 3):416-8. doi: 10.1107/s0907444997011736.
A novel maltogenic amylase from Bacillus stearothermophilus ET1, which has a dual activity of alpha-1,4- and alpha-1,6-glycosidic bond cleavages and alpha-1,6-glycosidic bond formation, was crystallized by using the hanging-drop vapor-diffusion method. The best crystals were obtained by employing a high concentration of protein (56 mg ml-1) and a precipitant containing 22% glycerol, 1.6 M ammonium sulfate in 0.1 M Tris-HCl (pH 8.5). Native diffraction data to 2.66 A resolution have been obtained from crystals flash-frozen at 110 K. The crystals belong to the space group P212121 with unit-cell dimensions of a = 77.62, b = 121.23, c = 244. 29 A, and contain three or four protomers per asymmetric unit. Structure determination by multiple isomorphous replacement is in progress.
一种来自嗜热脂肪芽孢杆菌ET1的新型产麦芽糖淀粉酶，它具有α-1,4-糖苷键和α-1,6-糖苷键裂解以及α-1,6-糖苷键形成的双重活性，采用悬滴气相扩散法进行了结晶。通过使用高浓度蛋白质（56 mg ml-1）和含有22%甘油、1.6 M硫酸铵的0.1 M Tris-HCl（pH 8.5）沉淀剂获得了最佳晶体。从在110 K下快速冷冻的晶体中获得了分辨率为2.66 Å的原生衍射数据。晶体属于空间群P212121，晶胞参数为a = 77.62、b = 121.23、c = 244.29 Å，每个不对称单元包含三个或四个原体。通过多重同晶置换进行结构测定正在进行中。
