title: Single step protocol to purify recombinant proteins with low endotoxin contents.
abstract: Endotoxin is an unwanted by product of recombinant proteins purified from Escherichia coli. The inherent toxicity of endotoxins makes their removal an important step for the proteins' application in several biological assays and for safe parenteral administration. The method described in this paper is a one-step protocol which is effective at removing tightly bound endotoxin from over-expressed tagged proteins in E. coli. We combined affinity chromatography with a non-ionic detergent washing step, to remove most of the endotoxin contaminants from the end product. An endotoxin reduction of less than 4 to 0.2 EU mg(-1) was achieved with protein recovery close to a yield 100%. As this new protocol requires only one step to simultaneously purify tagged proteins and eliminate endotoxins, it represents a substantial advantage in time, effort, and expense.
authors.affiliation: Department of Membrane Biochemistry, Max-Plank Institut für Biochemie, D-82152 Martinsried/Planegg, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Reichelt
authors.forename: Christoph
authors.initials: C
authors.lastname: Schwarz
authors.forename: Mariel
authors.initials: M
authors.lastname: Donzeau
mesh_terms: D000818:Animals; D002846:Chromatography, Affinity / Q000379:methods; D003902:Detergents / Q000737:chemistry; D004731:Endotoxins / Q000737:chemistry*; D004926:Escherichia coli; D006801:Humans; D011993:Recombinant Fusion Proteins / Q000737:chemistry* / Q000302:isolation & purification*
chemical_list: D003902:Detergents; D004731:Endotoxins; D011993:Recombinant Fusion Proteins