title: A simplified counter diffusion method combined with a 1D simulation program for optimizing crystallization conditions.
abstract: We developed a new protein crystallization method has been developed using a simplified counter-diffusion method for optimizing crystallization condition. It is composed of only a single capillary, the gel in the silicon tube and the screw-top test tube, which are readily available in the laboratory. The one capillary can continuously scan a wide range of crystallization conditions (combination of the concentrations of the precipitant and the protein) unless crystallization occurs, which means that it corresponds to many drops in the vapor-diffusion method. The amount of the precipitant and the protein solutions can be much less than in conventional methods. In this study, lysozyme and alpha-amylase were used as model proteins for demonstrating the efficiency of this method. In addition, one-dimensional (1-D) simulations of the crystal growth were performed based on the 1-D diffusion model. The optimized conditions can be applied to the initial crystallization conditions for both other counter-diffusion methods with the Granada Crystallization Box (GCB) and for the vapor-diffusion method after some modification.
authors.affiliation: Space Utilization Research Center, National Space Development Agency of Japan, Tsukuba, Ibaraki, 305-8505, Japan. PXW01674@nifty.ne.jp
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Tanaka
authors.forename: Koji
authors.initials: K
authors.lastname: Inaka
authors.forename: Shigeru
authors.initials: S
authors.lastname: Sugiyama
authors.forename: Sachiko
authors.initials: S
authors.lastname: Takahashi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Sano
authors.forename: Masaru
authors.initials: M
authors.lastname: Sato
authors.forename: Susumu
authors.initials: S
authors.lastname: Yoshitomi
mesh_terms: D002197:Capillary Action; D003198:Computer Simulation; D003460:Crystallization / Q000295:instrumentation / Q000379:methods*; D004058:Diffusion; D008956:Models, Chemical; D009113:Muramidase / Q000032:analysis* / Q000138:chemical synthesis / Q000737:chemistry*; D011786:Quality Control; D012965:Sodium Chloride / Q000737:chemistry*; D000516:alpha-Amylases / Q000032:analysis* / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D012965:Sodium Chloride; C421864:hen egg lysozyme; D000516:alpha-Amylases; D009113:Muramidase