[Studies on the solvent structure in protein crystals grown in microgravity].

Structures of Space- and ground-grown protein crystals were determined and compared for hen egg-white lysozyme and acidic phospholipase A2 from snake venom. The results show that microgravity might improve the structure of weakly bound ordered water molecules, though it could not change the protein conformation and the structure of solvent molecules bound stronger to protein molecules. The results also imply that the degree of quality improvement of microgravity-grown protein crystals might be related to the solvent content in protein crystals. These findings might, in a respect, reveal the mechanism of quality improvement of protein crystals grown in microgravity. In addition, due to the importance of water molecules in life activities, the confirmation of this preliminary conclusion might enlighten guidance in further studies of life science in microgravity.