Crystal Growth of Nitrogenase CrFe Protein and MnFe Protein in Space  

固氮酶CrFe蛋白和MnFe蛋白的空间晶体生长(英文)

作　　者：赵颖 赵剑峰 吕玉兵 黄巨富 王耀萍[2] 仓怀兴[2] 毕汝昌[2] 

机构地区：[1]中国科学院植物研究所光合作用与环境分子生理学重点实验室,北京100093 [2]中国科学院生物物理研究所,北京100101

出　　处：《Acta Botanica Sinica》2003年第9期1043-1048,共6页Acta Botanica Sinica（植物学报：英文版）

基　　金：国家载人航天工程;国家自然科学基金(30270296);国家重点基础研究发展规化项目(001CB1089-06)。~~

摘　　要：Nitrogenase CrFe protein and MnFe protein were purified from a mutant strain UW3 of Azotobacter vinelandii Lipmann grown on a medium containing Cr and Mn, respectively. In order to meet the requirement for crystal growth Of O-2-susceptible proteins including nitrogenase in space, crystallization conditions were optimized for the proteins using a simple and suitable device, as a replacement for the cumbersome anaerobic box (dry box), for anaerobic addition of the protein samples. In all used precipitant and protein solutions added in the simplified plexi glass box, CrFe protein and MnFe protein could be crystallized on the spacecraft in one week by the liquid/liquid diffusion method and vapor diffusion by the sitting drop method, respectively. All formed crystals were single on the spacecraft, but under the same condition twin crystals appeared on the ground. The size of the largest crystal grown in space from CrFe protein was 2-fold larger than that on the ground. But the size of the largest crystal grown in space from MnFe protein was not larger than that on the ground. The difference in crystal growth in space between CrFe protein and MnFe protein could be resulted from the crystallization method, rather than the kind of protein.从分别生长于含Mn和Cr培养基中的棕色固氮菌(Azotobacter vinelandii Lipmann)突变种UW3分离纯化出MnFe和CrFe蛋白。为适应包括固氮酶在内的氧敏感蛋白的空间晶体生长的要求,应用简易而适用的厌氧加样装置代替固氮酶实验室所用的笨重厌氧箱(dry box),在地面进行厌氧加样。在充满氮气的简便有机玻璃箱内厌氧加样的所有样品中,分别用液/液扩散法和汽相扩散的坐滴法都可在一周内使MnFe和CrFe蛋白在宇宙飞船上从溶液中结晶出来。在所用的数种蛋白沉淀剂中,飞船上形成的所有晶体都为单晶,而地面上在多数沉淀剂中都生成大量孪晶。在相同沉淀剂中用液/液扩散法,飞船上生成CrFe蛋白的最大晶体比地面生成的最大晶体大1倍。而在相同沉淀剂中用汽相扩散的坐滴法,飞船上生成的MnFe蛋白最大晶体却没有地面生成的最大晶体大。这种差异也许是由不同结晶方法而不是不同蛋白所引起的。

关 键 词：mutant UW3 of Azotobacter vinelandii O-2-susceptible proteins nitrogenase CrFe protein and MnFe protein crystal growth in space 

分 类 号：Q936[生物学—微生物学]