1obu
From Proteopedia
Apocrustacyanin C1 crystals grown in space and earth using vapour diffusion geometry
Structural highlights
Function[CRC1_HOMGA] Binds the carotenoid astaxanthin (AXT) which provides the blue coloration to the carapace of the lobster. Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedModels of apocrustacyanin C(1) were refined against X-ray data recorded on Bending Magnet 14 at the ESRF to resolutions of 1.85 and 2 A from a space-grown and an earth-grown crystal, respectively, both using vapour-diffusion crystal-growth geometry. The space crystals were grown in the APCF on the NASA Space Shuttle. The microgravity crystal growth showed a cyclic nature attributed to Marangoni convection, thus reducing the benefits of the microgravity environment, as reported previously [Chayen et al. (1996), Q. Rev. Biophys. 29, 227-278]. A subsequent mosaicity evaluation, also reported previously, showed only a partial improvement in the space-grown crystals over the earth-grown crystals [Snell et al. (1997), Acta Cryst. D53, 231-239], contrary to the case for lysozyme crystals grown in space with liquid-liquid diffusion, i.e. without any major motion during growth [Snell et al. (1995), Acta Cryst. D52, 1099-1102]. In this paper, apocrustacyanin C(1) electron-density maps from the two refined models are now compared. It is concluded that the electron-density maps of the protein and the bound waters are found to be better overall for the structures of apocrustacyanin C(1) studied from the space-grown crystal compared with those from the earth-grown crystal, even though both crystals were grown using vapour-diffusion crystal-growth geometry. The improved residues are on the surface of the protein, with two involved in or nearby crystal lattice-forming interactions, thus linking an improved crystal-growth mechanism to the molecular level. The structural comparison procedures developed should themselves be valuable for evaluating crystal-growth procedures in the future. Apocrustacyanin C(1) crystals grown in space and on earth using vapour-diffusion geometry: protein structure refinements and electron-density map comparisons.,Habash J, Boggon TJ, Raftery J, Chayen NE, Zagalsky PF, Helliwell JR Acta Crystallogr D Biol Crystallogr. 2003 Jul;59(Pt 7):1117-23. Epub 2003, Jun 27. PMID:12832753[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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