Lessons from crystals grown in the Advanced Protein Crystallisation Facility for conventional crystallisation applied to structural biology
Alessandro Vergara, Bernard Lorberc, Claude Sauter, ...et al - ASI Sponsor
Dec - 2005
DOI: 10.1016/j.bpc.2005.06.014

journal : Biophysical Chemistry

Volume : 118 ; Issue : 2-3
type: Article Journal

Abstract
The crystallographic quality of protein crystals that were grown in microgravity has been compared to that of crystals that were grown inparallel on earth gravity under otherwise identical conditions. A goal of this comparison was to assess if a more accurate 3D-structure can bederived from crystallographic analysis of the former crystals. Therefore, the properties of crystals prepared with the Advanced ProteinCrystallisation Facility (APCF) on earth and in orbit during the last decade were evaluated. A statistical analysis reveals that about half of thecrystals produced under microgravity had a superior X-ray diffraction limit with respect of terrestrial controls. Eleven protein structures couldbe determined at previously unachieved resolutions using crystals obtained in the APCF. Microgravity induced features of the most relevantstructures are reported. A second goal of this study was to identify the cause of the crystal quality enhancement useful for structuredetermination. No correlations between the effect of microgravity and other system-dependent parameters, such as isoelectric point or crystalsolvent content, were found except the reduced convection during the crystallisation process. Thus, crystal growth under diffusive regimeappears to be the key parameter explaining the beneficial effect of microgravity on crystal quality. The mimicry of these effects on earth ingels or in capillary tubes is discussed and the practical consequences for structural biology highlighted.

keywords : Protein structure; Crystal quality; Microgravity; Diffusion; Advanced Protein Crystallisation Facility

Notes : AV and AZ acknowledge the Italian Space Agency (ASI) for financial support provided until 2001