title: Affinity-trap polyacrylamide gel electrophoresis: a novel method of capturing specific proteins by electro-transfer.
abstract: A method for the affinity capture of specific proteins from a complex mixture using a polyacrylamide gel technique is described. The approach is based on the orthogonal electro-transfer of proteins separated by ordinary polyacrylamide gel electrophoresis (PAGE) to a ligand-coupled polyacrylamide gel (Li-PAG), which is placed under the PAGE gel. Upon electro-transfer, the proteins orthogonally migrate from the PAGE into the Li-PAG, based on the net charge. During migration to the Li-PAG, proteins that specifically interact with a ligand can be transiently trapped in the Li-PAG, while those that do not interact with a ligand pass through it. This method permits the separation of the proteins that can specifically interact with a ligand, even when present in a complex mixture. The method is demonstrated by applying it to the one-step isolation of a trypsin inhibitor from a crude extract of soybean flour.
authors.affiliation: Laboratory of Protein Profiling and Functional Proteomics, Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
authors.forename: Chihiro
authors.initials: C
authors.lastname: Awada
authors.forename: Takashi
authors.initials: T
authors.lastname: Sato
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Takao
mesh_terms: D000595:Amino Acid Sequence; D004579:Electron Transport; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods*; D055767:Immobilized Proteins / Q000737:chemistry; D008969:Molecular Sequence Data; D013025:Glycine max / Q000737:chemistry; D014357:Trypsin / Q000737:chemistry*; D014361:Trypsin Inhibitors / Q000032:analysis* / Q000302:isolation & purification
chemical_list: D055767:Immobilized Proteins; D014361:Trypsin Inhibitors; D014357:Trypsin