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Title: Humidity control and hydrophilic glue coating applied to mounted protein crystals improves X-ray diffraction experiments

Abstract

A new crystal-mounting method has been developed that involves a combination of controlled humid air and polymer glue for crystal coating. This method is particularly useful when applied to fragile protein crystals that are known to be sensitive to subtle changes in their physicochemical environment. Protein crystals are fragile, and it is sometimes difficult to find conditions suitable for handling and cryocooling the crystals before conducting X-ray diffraction experiments. To overcome this issue, a protein crystal-mounting method has been developed that involves a water-soluble polymer and controlled humid air that can adjust the moisture content of a mounted crystal. By coating crystals with polymer glue and exposing them to controlled humid air, the crystals were stable at room temperature and were cryocooled under optimized humidity. Moreover, the glue-coated crystals reproducibly showed gradual transformations of their lattice constants in response to a change in humidity; thus, using this method, a series of isomorphous crystals can be prepared. This technique is valuable when working on fragile protein crystals, including membrane proteins, and will also be useful for multi-crystal data collection.

Authors:
; ; ;  [1]
  1. Japan Synchrotron Radiation Research Institute (JASRI/SPring-8), 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan)
Publication Date:
OSTI Identifier:
22347823
Resource Type:
Journal Article
Resource Relation:
Journal Name: Acta Crystallographica. Section D: Biological Crystallography; Journal Volume: 69; Journal Issue: Pt 9; Other Information: PMCID: PMC3760132; PMID: 23999307; PUBLISHER-ID: tz5035; OAI: oai:pubmedcentral.nih.gov:3760132; Copyright (c) Baba et al. 2013; This is an open-access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
Denmark
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AIR; CRYSTALS; ENVIRONMENT; HUMIDITY; IRON; POLYMERS; TRANSFORMATIONS; WATER; X-RAY DIFFRACTION

Citation Formats

Baba, Seiki, Hoshino, Takeshi, Ito, Len, and Kumasaka, Takashi, E-mail: kumasaka@spring8.or.jp. Humidity control and hydrophilic glue coating applied to mounted protein crystals improves X-ray diffraction experiments. Denmark: N. p., 2013. Web. doi:10.1107/S0907444913018027.
Baba, Seiki, Hoshino, Takeshi, Ito, Len, & Kumasaka, Takashi, E-mail: kumasaka@spring8.or.jp. Humidity control and hydrophilic glue coating applied to mounted protein crystals improves X-ray diffraction experiments. Denmark. doi:10.1107/S0907444913018027.
Baba, Seiki, Hoshino, Takeshi, Ito, Len, and Kumasaka, Takashi, E-mail: kumasaka@spring8.or.jp. 2013. "Humidity control and hydrophilic glue coating applied to mounted protein crystals improves X-ray diffraction experiments". Denmark. doi:10.1107/S0907444913018027.
@article{osti_22347823,
title = {Humidity control and hydrophilic glue coating applied to mounted protein crystals improves X-ray diffraction experiments},
author = {Baba, Seiki and Hoshino, Takeshi and Ito, Len and Kumasaka, Takashi, E-mail: kumasaka@spring8.or.jp},
abstractNote = {A new crystal-mounting method has been developed that involves a combination of controlled humid air and polymer glue for crystal coating. This method is particularly useful when applied to fragile protein crystals that are known to be sensitive to subtle changes in their physicochemical environment. Protein crystals are fragile, and it is sometimes difficult to find conditions suitable for handling and cryocooling the crystals before conducting X-ray diffraction experiments. To overcome this issue, a protein crystal-mounting method has been developed that involves a water-soluble polymer and controlled humid air that can adjust the moisture content of a mounted crystal. By coating crystals with polymer glue and exposing them to controlled humid air, the crystals were stable at room temperature and were cryocooled under optimized humidity. Moreover, the glue-coated crystals reproducibly showed gradual transformations of their lattice constants in response to a change in humidity; thus, using this method, a series of isomorphous crystals can be prepared. This technique is valuable when working on fragile protein crystals, including membrane proteins, and will also be useful for multi-crystal data collection.},
doi = {10.1107/S0907444913018027},
journal = {Acta Crystallographica. Section D: Biological Crystallography},
number = Pt 9,
volume = 69,
place = {Denmark},
year = 2013,
month = 9
}
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