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A generic protocol for protein crystal dehydration using the HC1b humidity controller.

ABSTRACT: Dehydration may change the crystal lattice and affect the mosaicity, resolution and quality of X-ray diffraction data. A dehydrating environment can be generated around a crystal in several ways with various degrees of precision and complexity. This study uses a high-precision crystal humidifier/dehumidifier to provide an airstream of known relative humidity in which the crystals are mounted: a precise yet hassle-free approach to altering crystal hydration. A protocol is introduced to assess the impact of crystal dehydration systematically applied to nine experimental crystal systems. In one case, that of glucose isomerase, dehydration triggering a change of space group from I222 to P21212 was observed. This observation is supported by an extended study of the behaviour of the glucose isomerase crystal structure during crystal dehydration.

SUBMITTER: Lobley CM

PROVIDER: S-EPMC4854313 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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A generic protocol for protein crystal dehydration using the HC1b humidity controller.

Lobley Carina M C CM Sandy James J Sanchez-Weatherby Juan J Mazzorana Marco M Krojer Tobias T Nowak Radosław P RP Sorensen Thomas L TL

Acta crystallographica. Section D, Structural biology 20160426 Pt 5

Dehydration may change the crystal lattice and affect the mosaicity, resolution and quality of X-ray diffraction data. A dehydrating environment can be generated around a crystal in several ways with various degrees of precision and complexity. This study uses a high-precision crystal humidifier/dehumidifier to provide an airstream of known relative humidity in which the crystals are mounted: a precise yet hassle-free approach to altering crystal hydration. A protocol is introduced to assess the ...[more]

PMID: 27139626

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