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Crystallization of human complement component C5.

R G Discipio·L Jenner·S Thirup·L Sottrup-Jensen·J Nyborg·E Stura
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Abstract

Human complement component C5 has been crystallized using a low-salt batch technique. The crystals are large hexagonal bi-pyramids often larger than 1.5 mm. Although these crystals were grown in low salt (0.1 M NaCl), they are remarkably stable for at least 2 months at 281 K and they are not dissolved in aqueous buffers containing up to 2 M sodium chloride. The space group is P3121 or P3221, and the cell parameters were determined to be a = 144.9, b = 144.9, c = 243.1 A; alpha = 90 degrees, beta = 90, gamma = 120 degrees. At room temperature and cryo-temperatures the crystals diffract at best to 6 A using rotating-anode X-ray sources. Using synchrotron radiation with cryoprotection using 40%(v/v) PEG 400 the resolution limit can be extended to 3.3 A. In both cases the crystals show significant anisotropy, with relatively weaker reflections at higher resolution in the a*b* plane.

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AnisotropyComplement C5CrystallizationCrystallography, X-RayHumansProtein ConformationSynchrotronsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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R G Discipio, L Jenner, S Thirup, L Sottrup-Jensen, J Nyborg, E Stura. 1998-07-01. Crystallization of human complement component C5.. https://doi.org/10.1107/s0907444997015011

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