Ammonium sulfate-mediated chromatography

To summarize this set of observations, halophilic proteins adsorb to polysaccharide matrices at high ammonium sulfate concentration. When the matrix is charged the adsorption of proteins having the same charge on the matrix is reduced whereas the adsorption of proteins having opposite charge is greatly facilitated. These observations enabled the development of several powerful purification 

Elution of Two Halophilic Enzymes by Decreasing Concentration Gradients of Ammonium Sulfate  

Not eluted the enzymes did not elute until the concentration was 0.4 M (NH4)2S04 [0.3 M (NH4)2S04 in the case of GDH]. They could, however, be eluted by a NaCl gradient. 

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