Abstract
Cashmere, wool and yak were reduced with dithiothreitol in 0.1 M phosphate buffer (pH 7.8) containing 4% sodium dodecyl sulfate at 95℃. Keratin proteins were extracted with around 80% yield. Higher SDS concentration and temperature were important factor for effective extraction of keratin proteins from wool and animal fiber. More than 8 bands were observed in SDS-PAGE analysis of extracted proteins. Maldi-Tof mass analysis of tryptic digests of major bands in SDS-PAGE and data base search showed that those bands are assigned to be keratin I and II. Typical peaks for keratin I of cashmere, wool and yak were observed in the region between 2500 and 2700 m/z in mass spectra and these peaks were shown to be very useful for identification of cashmere, wool and yak.
