title: Humidity control and hydrophilic glue coating applied to mounted protein crystals improves X-ray diffraction experiments.
abstract: 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.affiliation: Structural Biology Group, Japan Synchrotron Radiation Research Institute (JASRI/SPring-8), 1-1-1 Kouto, Sayo, Hyogo 679-5198, Japan.
authors.forename: Seiki
authors.initials: S
authors.lastname: Baba
authors.forename: Takeshi
authors.initials: T
authors.lastname: Hoshino
authors.forename: Len
authors.initials: L
authors.lastname: Ito
authors.forename: Takashi
authors.initials: T
authors.lastname: Kumasaka
mesh_terms: D000269:Adhesives / Q000737:chemistry*; D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry; D002417:Cattle; D003460:Crystallization; D005982:Glutathione Transferase / Q000737:chemistry; D006801:Humans; D006813:Humidity; D007328:Insulin / Q000737:chemistry; D008565:Membrane Proteins / Q000737:chemistry*; D015203:Reproducibility of Results; D014961:X-Ray Diffraction / Q000295:instrumentation / Q000379:methods / Q000706:statistics & numerical data
chemical_list: D000269:Adhesives; D001426:Bacterial Proteins; D007328:Insulin; D008565:Membrane Proteins; D005982:Glutathione Transferase; C041116:leukotriene-C4 synthase
keywords: cryocrystallography; crystal mounting; macromolecular crystallography