CRYSTALLIZATION UNDER MICROGRAVITY OF ACIDIC PHOSPHOLIPASE A(2) FROM VENOM OF AGKISTRODON HALYS PALLAS

A series of space crystallization experiments of an acidic phospholipa se A, from venom of Agkistrodon halys Pallas were performed in August 1992 and in July 1994. On both missions, compared with earth-grown cry stals in control experiments, space-grown crystals were larger, had fe wer nuclei, and exhibited better habit. Significant improvements in cr ystal quality were achieved on 1994's mission, and the space-grown cry stals exhibited stronger diffraction patterns and diffracted X-rays to high resolutions. Relative Wilson plots indicated that the space-grow n crystals had higher internal order than the best laboratory-grown cr ystal. In addition, the results of the two space experiments suggested that the optimization of the space crystallization conditions, especi ally when an unconventional crystal growth method is engaged, plays an important role in exploiting microgravity more efficiently.