High-resolution structure (1.33 angstrom) of a HEW lysozyme tetragonal crystal grown in the APCF apparatus. Data and structural comparison with a crystal grown under microgravity from SpaceHab-01 mission
High-resolution structure (1.33 angstrom) of a HEW lysozyme tetragonal crystal grown in the APCF apparatus. Data and structural comparison with a crystal grown under microgravity from SpaceHab-01 mission
复制标题
DOI：
10.1107/s090744499501674x
复制
发表时间：
1996-05-01
影响因子：
2.2
通讯作者：
Ducruix, A
中科院分区：
文献类型：
--
作者：
Vaney, MC;Maignan, S;Ducruix, A
利用先进的蛋白质结晶设备(APCF)在微重力环境(Spacehab-01任务)和地面控制条件下生长了四方蛋清溶菌酶晶体。晶体生长以氯化钠为结晶剂，PH值为4.3。用同步辐射和像片记录了最佳衍射型地面和空间生长晶体的X射线衍射图。地面和太空生长的晶体显示出几乎相同的最大分辨率1.3-1.4埃。用X-PLOR程序对研磨晶体和空间生长晶体的结构进行了改进，最终R值分别为18.45%和18.27%。这两种结构几乎相同，所有蛋白质原子的均方根差为0.13埃。这两种精制结构的一些残基显示出多种替代构象。两个离子被定位在两个结构的电子密度图中：一个氯离子在两个对称相关分子之间的界面上，一个钠离子稳定Ser60-Leu75环。钠离子被六个配体包围，它们在2.2-2.6埃的距离处形成一个双金字塔。
Crystals of tetragonal hen egg-white lysozyme were grown using Advanced Protein Crystallization Facility (APCF) apparatus under a microgravity environment (SpaceHab-01 mission) and ground control conditions. Crystals were grown from NaCl as a crystallizing agent at PH 4.3. The X-ray diffraction patterns of the best diffracting ground- and space-grown crystals were recorded using synchrotron radiation and an image plate on the W32 beamline at LURE. Both ground- and space-grown crystals showed nearly equivalent maximum resolution of 1.3-1.4 Angstrom. Refinements were carried out with the program X-PLOR with final R values of 18.45 and 18.27% for structures from ground- and space grown crystals, respectively. The two structures are nearly identical with the root-mean-square difference on all protein atoms being 0.13 Angstrom. Some residues of the two refined structures show multiple alternative conformations. Two ions were localized into the electron-density maps of the two structures: one chloride ion at the interface between two symmetry-related molecules and one sodium ion stabilizing the loop Ser60-Leu75. The sodium ion is surrounded by six ligands which form a bipyramid around it at distances of 2.2-2.6 Angstrom.