Methods and compositions for protein purification

Abstract

The present invention provides methods of purifying proteins that include a metal ion affinity peptide. The methods generally involve contacting a fusion protein that includes a metal ion affinity peptide with at least two different metal ion chelating resins. In certain representative embodiments, the methods include contacting a fusion protein with a first metal ion chelate resin having a first immobilized metal ion; eluting any bound protein from the first metal ion chelate resin, to produce an eluate; contacting the eluate with a second metal ion chelate resin having a second immobilized metal ion; and eluting any bound protein from the second metal ion chelate resin. Also provided are kits for use in practicing the subject methods. The subject methods find use in a variety of protein purification applications.

Dependencies are inferred from the claim text.