Stura E A, Ghosh S, Garcia-Junceda E, Chen L, Wong C H, Wilson I A
Department of Molecular Biology, Scripps Research Institute, La Jolla, California 92037, USA.
Proteins. 1995 May;22(1):67-72. doi: 10.1002/prot.340220110.
X-ray quality crystals of class I-deoxyribose-5-phosphate aldolase from Escherichia coli have been obtained for the unliganded enzyme and in complex with its substrate, 2-deoxyribose-5-phosphate. The enzyme catalyzes the reversible cleavage of 2-deoxyribose-5-phosphate to acetaldehyde and D-glyceraldehyde-3-phosphate. The unliganded and complex crystals are prismatic long rods and belong to the orthorhombic space group P2(1)2(1)2(1) with cell dimensions a = 183.1 A, b = 61.4 A, c = 49.3 A and a = 179.2 A, b = 60.5, A, c = 49.1 A, respectively. Two molecules in the asymmetric unit are related by a noncrystallographic 2-fold axis. The crystals are stable in the X-ray beam and diffract to at least 2.6 A. A new method, reverse screening, designed to minimize protein utilization during the screening process was used to determine supersaturation and crystallization conditions.
已获得来自大肠杆菌的I类脱氧核糖-5-磷酸醛缩酶的X射线质量晶体，该晶体为未结合配体的酶及其与底物2-脱氧核糖-5-磷酸的复合物。该酶催化2-脱氧核糖-5-磷酸可逆裂解为乙醛和D-甘油醛-3-磷酸。未结合配体的晶体和复合物晶体均为棱柱形长棒，属于正交晶系空间群P2(1)2(1)2(1)，晶胞参数分别为a = 183.1 Å，b = 61.4 Å，c = 49.3 Å和a = 179.2 Å，b = 60.5 Å，c = 49.1 Å。不对称单元中的两个分子通过一个非晶体学2重轴相关。这些晶体在X射线束中稳定，衍射能力至少达到2.6 Å。一种旨在在筛选过程中尽量减少蛋白质用量的新方法——反向筛选，被用于确定过饱和度和结晶条件。
