title: Affinity partitioning of proteins tagged with choline-binding modules in aqueous two-phase systems.
abstract: We present a novel procedure for affinity partitioning of recombinant proteins fused to the choline-binding module C-LytA in aqueous two-phase systems containing poly(ethylene glycol) (PEG). Proteins tagged with the C-LytA module and exposed to the two-phase systems are quantitatively localized in the PEG-rich phase, whereas subsequent addition of the natural ligand choline specifically shifts their localization to the PEG-poor phase by displacement of the polymer from the binding sites. The described procedure is simple, scalable and reproducible, and has been successfully applied to the purification of four diverse proteins, resulting in high yields and purity.
authors.affiliation: Instituto de Biología Molecular y Celular, Universidad Miguel Hernández, Avda. Universidad s/n, 03202 Elche (Alicante), Spain.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Maestro
authors.forename: Isabel
authors.initials: I
authors.lastname: Velasco
authors.forename: Isabel
authors.initials: I
authors.lastname: Castillejo
authors.forename: Miguel
authors.initials: M
authors.lastname: Arévalo-Rodríguez
authors.forename: Angel
authors.initials: A
authors.lastname: Cebolla
authors.forename: Jesús M
authors.initials: JM
authors.lastname: Sanz
mesh_terms: D002794:Choline / Q000737:chemistry; D002846:Chromatography, Affinity / Q000379:methods*; D011092:Polyethylene Glycols / Q000737:chemistry; D011993:Recombinant Fusion Proteins / Q000302:isolation & purification*
chemical_list: D011993:Recombinant Fusion Proteins; D011092:Polyethylene Glycols; D002794:Choline