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A simplified counter diffusion method combined with a 1D simulation program for optimizing crystallization conditions.

Hiroaki Tanaka·Koji Inaka·Shigeru Sugiyama·Sachiko Takahashi·Satoshi Sano·Masaru Sato·Susumu Yoshitomi
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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.

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Capillary ActionComputer SimulationCrystallizationDiffusionModels, ChemicalMuramidaseQuality ControlSodium Chloridealpha-AmylasesComparative StudyEvaluation StudyJournal ArticleValidation Study

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Hiroaki Tanaka, Koji Inaka, Shigeru Sugiyama, Sachiko Takahashi, Satoshi Sano, Masaru Sato, Susumu Yoshitomi. 2003-11-28. A simplified counter diffusion method combined with a 1D simulation program for optimizing crystallization conditions.. https://doi.org/10.1107/s0909049503023446

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