Improvements in the order, isotropy and electron density of glypican-1 crystals by controlled dehydration

• Published in: Acta crystallographica. Section D, Biological crystallography. Vol. 69; no. 12; pp. 2524 - 2533
• Main Authors: Awad, Wael, Svensson Birkedal, Gabriel, Thunnissen, Marjolein M. G. M., Mani, Katrin, Logan, Derek T.
• Format: Journal Article
• Language: English
• Published: 5 Abbey Square, Chester, Cheshire CH1 2HU, England International Union of Crystallography 01.12.2013; Wiley Subscription Services, Inc
• Subjects: ANISOTROPY; AUGMENTATION; Biologi; Biological Sciences; CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; crystal dehydration; crystal packing; Crystallization - methods; Crystallography, X-Ray - methods; CRYSTALS; DEHYDRATION; DENSITY; DIFFRACTION; diffraction anisotropy; ELECTRON DENSITY; ELECTRONS; glypican-1; Glypicans - chemistry; HC1; Humans; HUMIDITY; ISOTROPY; Models, Molecular; Natural Sciences; Naturvetenskap; OPTIMIZATION; Protein Conformation; PROTEINS; Research Papers; Structural Biology; Strukturbiologi; Water - chemistry; crystal dehydration; crystal packing; optimization; diffraction anisotropy; glypican-1; HC1
• ISSN: 1399-0047; 0907-4449; 1399-0047
• DOI: 10.1107/S0907444913025250

The use of controlled dehydration for improvement of protein crystal diffraction quality is increasing in popularity, although there are still relatively few documented examples of success. A study has been carried out to establish whether controlled dehydration could be used to improve the anisotropy of crystals of the core protein of the human proteoglycan glypican‐1. Crystals were subjected to controlled dehydration using the HC1 device. The optimal protocol for dehydration was developed by careful investigation of the following parameters: dehydration rate, final relative humidity and total incubation time Tinc. Of these, the most important was shown to be Tinc. After dehydration using the optimal protocol the crystals showed significantly reduced anisotropy and improved electron density, allowing the building of previously disordered parts of the structure.