神舟八号飞船空间蛋白质结晶实验

 利用德国空间生物实验装置和自主研制的结晶室,在中国神舟八号飞船上进行了14种蛋白质的结晶实验,实验持续16.5d;同时使用相同结晶室在地面开展比对实验.结果表明：12种蛋白质在空间析出晶体,地面有11种;空间析出的6种蛋白质晶体可用于X-射线衍射实验,收得4种晶体的8套同步辐射衍射数据;地面有5种蛋白质晶体可用于X-射线衍射,收得3种晶体的5套同步辐射衍射数据,其中1套不完整.鸡蛋清溶菌酶空间晶体的初步衍射最高分辨率为1.16Å,地面晶体的为1.23Å.痢疾杆菌二磷酸四腺苷空间晶体初步衍射最高分辨率为1.75Å,地面晶体的为1.49Å,但是1颗空间晶体的晶型发生改变.衣原体蛋白酶样活化因子空间晶体的初步衍射最高分辨率为2.31Å,地面晶体未得到衍射数据.加拿大的17β-羟化类固醇脱氢酶复合物空间晶体的初步衍射最高分辨率为2.30Å,地面晶体未得到完整衍射数据.自主研制的结晶室的浸入式毛细管结构为国际上首次采用,具有无源和通用的优点,对汽相扩散结晶法具有良好的自然对流抑制效果.

Protein Crystallization Experiments Aboard Shenzhou-8 Spaceship

The crystallization experiments of 14 proteins were carried out, the experiment was lasted 16.5 days by using German Biobox facility and self-developed growth chambers aboard Shenzhou-8 spaceship. The counterpart experiment was performed on the ground laboratory according to the same timing sequence. The results show that 12 of 14 proteins precipitate crystals in space experiment, 11 of 14 proteins precipitate crystals on ground experiment. Eight space-grown crystals of four proteins are applied to synchrotron radiation, and eight set diffraction data are obtained. In the meantime, five earth-grown crystals of three proteins are applied to synchrotron radiation, and five set diffraction data are obtained, among them, one set is incomplete. The highest preliminary diffraction resolutions of space- and earth-grown lysozyme crystals are 1.16Å and 1.23Å, respectively. However, is the highest resolutions are 1.75Å and 1.49Å, respectively for the crystals of diadenosine tetraphosphate from dysentery bacillus; nevertheless one space-grown crystal has different crystallographic symmetry from other crystals. The highest diffraction resolution for the space-grown crystal of the chlamydial protease-like activating factor diffracted is 2.31Å, the ground one fails to diffraction. The highest diffraction resolution for the space-grown crystal of 17β-hydroxysteroid dehydrogenase type 7 complex from Canada is 2.30Å, the ground one is not good enough for collecting a complete diffraction data set. The growth chambers used in space experiment adopt a new structure for the first time in the world of which the protein solution container is made of glass capillary and immersed in the precipitation solution. The new growth chamber is portable, works without power supply, and is able to eliminate Marangoni convection in the vapor diffusion chamber.