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2012207395

1.Batch crystallization

Vapor diffusion crystallization

Hanging drop methodSitting drop method liquid-liquid diffusion crystallization

Traditional L-L diffusion

Granada crystallization boxDialysis crystallization

. influence factor1.Protein purity

By far the most important factor in crystallization is the purity of the protein sample.

Another fundamental precept of crystallization is the absolute homogeneity of the protein sample.. influence factor2.Supersaturation

the optimal conditions would have to begin with the formation of a preferably single nucleus in the nucleation zone just beyond the metastable zone. influence factor3.Precipitant

. influence factor4.pH most crystallize at physiological pH (around 7.5).

For some proteins, crystallization occurs over a very broad range of pH with little variation in crystal morphology.

In some cases, the pI of the protein is the pH at which the best crystals grow.. influence factor5.TemperatureMost crystallize either at 4 or 18 - 22 (room temperature).

The solubility of proteins in salt solutions tends to increase at low temperatures, whereas in PEG and MPD solutions, protein solubility generally decreases with decreasing temperature. .

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