Patent ID: 9617299
Date: 2017-04-11
CPC Classifications: C07K

Claim:
1. A method of purifying a fusion protein, comprising: (1) adjusting the pH of an aqueous phase, comprising a fusion protein which is a fusion of a protein having a self-assembly capability and a target protein, and which aqueous phase has a first pH, to a second pH, to obtain a remaining aqueous phase and a solid fraction comprising an amount of said fusion protein; (2) separating said solid fraction from said remaining aqueous phase, to obtain a separated solid fraction; and (3) dissolving said separated solid fraction in a solution having a pH of 12 or lower but higher than said second pH by at least 0.1 pH units, wherein said protein having a self-assembly capability is a cell surface protein that is a CspB mature protein or a portion thereof; and wherein (i) said target protein has 10 to 300 amino acid residues, or (ii) the ratio of the number of amino acid residues in the target protein to the number of amino acid residues in the CspB mature protein or portion thereof is in a range of 0.3 to 14.