Differential precipitation and solubilization of proteins.
Differential protein precipitation is a rapid and economical step in protein purification and is based on exploiting the inherent physico-chemical properties of the polypeptide. Precipitation of recombinant proteins, lysed from the host cell, is commonly used to concentrate the protein of choice before further polishing steps with more selective purification columns (e.g. His-Tag, Size Exclusion, etc.). Recombinant proteins can also precipitate naturally as inclusion bodies due to various influences during over-expression in the host cell. Although this phenomenon permits easier initial separation from native proteins, these inclusion bodies must carefully be differentially solubilised so as to reform functional, correctly folded proteins. Here, a typical protein extraction, precipitation, and selective resolubilisation procedure is outlined, based on a recombinantly expressed protein.
Ryan
Barry J
BJ
School of Food Science and Environmental Health, Dublin Institute of Technology, Dublin, Ireland.
D000645:Ammonium Sulfate / Q000737:chemistry; D005591:Chemical Fractionation / Q000379:methods*; D011232:Chemical Precipitation; D058849:Protein Refolding; D011506:Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification*; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D012995:Solubility; D014238:Trichloroacetic Acid / Q000737:chemistry
D011506:Proteins; D011994:Recombinant Proteins; D014238:Trichloroacetic Acid; D000645:Ammonium Sulfate