METHODS FOR SEPARATING RECOMBINANT PROTEINS IN AQUEOUS TWO-PHASE SYSTEMS.

摘要

The invention relates to a method for distributing, separating and purifying recombinant proteins in aqueous solution, based on the use of polypeptides with choline affinity. The invention is based on a phenomenon by which two aqueous solutions with pre-determined components can be mixed, ultimately being divided into two phases of different densities. The proteins bound to the above-mentioned polypeptides with choline affinity are preferably located in one of the phases, while the majority of the proteins from a cellular extract tend to move to the opposite phase. Following a series of washing operations to eliminate the remaining unwanted material the location of the proteins may be reversed with the addition of a soluble molecule with affinity for the polypeptide bound the protein of interest. The invention comprises a convenient method for altering the presence of the protein or polypeptide of interest in one phase or the other, thereby enabling the purification of same with a high performance and degree of purity. The invention is a cost-effective scalable method for separating recombinant proteins preferably labeled with choline-binding domains.