Development of Membrane Supports for the Solid-phase Sequence Analysis of Proteins and Peptides

Abstract

The solid phase method of protein sequence analysis (Laursen, 1971) requires the covalent attachment of a peptide or protein to a solid matrix that is stable to the reaction conditions of the Edman degradation. Although a variety of support matrices and attachment chemistries have been described (for a review see Laursen and Machleidt, 1980) the commonly employed covalent attachment supports have been diisothiocyanate (DITC) derivatized glass beads (Wachter et al., 1973) or DITC functionalized glass fiber sheets (Aebersold et al., 1986). Both types of matrices react efficiently with the ∈-amino groups of the lysine side chains of peptides and proteins. For the protein sequencer, the most significant advantage of the latter support is that proteins that have been resolved by gel electrophoresis can be electroblotted directly onto DITC-activated glass fiber sheets with covalent attachment occurring during the transfer. Although employed quite effectively in this application, the DITC glass fiber sheets were mechanically fragile, with rather low protein binding capacity, and it proved difficult to detect the protein molecules on the glass surface.