title: Gas-phase sequencing after electroblotting on polyvinylidene difluoride membranes assigns correct molecular weights to myoglobin molecular weight markers.
abstract: Commercially available polypeptide marker kits containing peptides generated by cyanogen bromide cleavage of either horse heart myoglobin or sperm whale myoglobin have been investigated by sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE), followed by electroblotting on polyvinylidene difluoride membranes, and gas-phase sequencing. It could be shown that the molecular weights assigned to the SDS-PAGE bands by the companies are incorrect. Arranged in descending order, the marker kits are composed of the following polypeptide fragments from myoglobin: positions 1-153, 1-131, 56-153, 56-131, 1-55, and 132-153. A polypeptide comprising residues 1-14 was not found. According to these results the log Mr versus Rf plot used for calibration must be revised. For the separation of low molecular weight polypeptides and peptides a new gel system based on the theory of multiphasic zone electrophoresis combined with a modified Coomassie staining procedure is reported.
authors.affiliation: Max-Planck-Institut für experimentelle Medizin, Abteilung für Immunchemie, Goettingen, West Germany.
authors.forename: H D
authors.initials: HD
authors.lastname: Kratzin
authors.forename: J
authors.initials: J
authors.lastname: Wiltfang
authors.forename: M
authors.initials: M
authors.lastname: Karas
authors.forename: V
authors.initials: V
authors.lastname: Neuhoff
authors.forename: N
authors.initials: N
authors.lastname: Hilschmann
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D006736:Horses; D008567:Membranes, Artificial; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009211:Myoglobin / Q000032:analysis*; D011145:Polyvinyls; D005465:Fluorocarbon Polymers
chemical_list: D008567:Membranes, Artificial; D009211:Myoglobin; D011145:Polyvinyls; C024865:polyvinylidene fluoride; D005465:Fluorocarbon Polymers