PEPTIDE-MAPPING OF S-CARBOXYMETHYLATED HAIR AND FEATHER PROTEINS USING 2-DIMENSIONAL ELECTROPHORESIS

The aim of this work was to develop a two-dimensional electrophoretic method for the multiple simultaneous peptide mapping of a broad spectr um of human and animal hair and avian feather proteins, The C-14 label led S-carboxymethylated proteins of hair and feather were separated in one dimension by sodium dodecyl sulphate-polyacrylamide slab gel elec trophoresis and stained with Coomassie Blue, Each of the gel lanes con taining the separated hair or feather proteins from one individual was cut and transferred at right angles on to a second slab gel, A soluti on of trypsin (5 mu g/ml) in stacking gel buffer was poured on to the gel lane, Partial proteolysis of the hair or feather proteins proceede d in situ while the stacking gel buffer set, The second dimension of e lectrophoresis followed by staining and/or fluorography showed a chara cteristic pattern of peptides of proteins in the form of spots derived from each individual protein, leaving undigested proteins well separa ted on the diagonal, The protease digestion pattern was reproducible a nd characteristic of each sample, We were able to establish a finer pe ptide signature, for individual samples containing a mixture of many p roteins, than was hitherto possible with previously published two-dime nsional electrophoretic techniques, It was concluded that this techniq ue may be of use in future evolutionary, ontogenetic and forensic stud ies using hair and feathers as a biological source material. Copyright (C) Elsevier Science Ltd