title: Proteome analysis of polyacrylamide gel-separated proteins visualized by reversible negative staining using imidazole-zinc salts.
abstract: Identification and characterization of proteins isolated from natural sources by polyacrylamide gel electrophoresis has become a routine technique. However, efficient sample proteolysis and subsequent peptide extraction is still problematic. Here, we present an improved protocol for the rapid detection of polyacrylamide gel-separated proteins, in situ protein modification, proteolytic digestion and peptide extraction for subsequent protein identification and characterization by capillary high-performance liquid chromatography/tandem mass spectrometry. This simple technique employs the rapid imidazole-zinc reverse stain, in-gel S-pyridylethylation and proteolytic digestion of microcrushed polyacrylamide gel pieces with proteases. This technique obviates the need for buffer exchange or gel lyophilisation due to all of the sample manipulation steps being carried out at near neutral pH and thus lends itself readily to automation.
authors.affiliation: Center for Genetic Engineering and Biotechnology (CIGB) Havana, Cuba.
authors.forename: L
authors.initials: L
authors.lastname: Castellanos-Serra
authors.forename: W
authors.initials: W
authors.lastname: Proenza
authors.forename: V
authors.initials: V
authors.lastname: Huerta
authors.forename: R L
authors.initials: RL
authors.lastname: Moritz
authors.forename: R J
authors.initials: RJ
authors.lastname: Simpson
mesh_terms: D000180:Acrylic Resins; D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods*; D006801:Humans; D007093:Imidazoles; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D016624:Negative Staining / Q000379:methods*; D011506:Proteins / Q000302:isolation & purification*; D012492:Salts; D015032:Zinc
chemical_list: D000180:Acrylic Resins; D007093:Imidazoles; D011506:Proteins; D012492:Salts; C016680:polyacrylamide gels; D015032:Zinc