Study on Loading Techniques of Protein Species into Space Crystallization Chamber

The prerequisite of using X-ray diffracting technique to study the relation between protein molecular structure and its function is to obtain the protein crystals of high quality. The microgravity environment of space is an ideal place for culturing such protein crystals. The experimental yield of the space protein crystallization is affected heavily by the loading techniques of the protein species into the crystallization chamber. The loading technique of protein species into the new-designed crystallization chamber for protein crystallization experiment aboard Shenzhou-8 spaceship is studied systematically. It is deduced that the needle shape of the pipette, the protein loading tool, the holding manner of the glass capillary tube, the qualities of sealing and siliconization of the tube have remarkable influences on the experimental results of protein crystallization, which were proved to result in the inclusion of gas bubbles. The corresponding measures such as improving sealing technique and protein loading pipette, constructing a tube-holding tool, are adopted to optimize loading technique and eliminate the gas bubbles. The new techniques have been implemented successfully to the final space experiment of protein crystallization aboard Shenzhou-8 spaceship.