Complete Amino Acid Sequence of the N-Terminal Cyanogen Bromide Fragment CNBr-3 From a Microfibrillar Protein From Wool

Abstract

The amino acid sequence of a 59-residue 'non-helical tail' from a low-sulfur microfibrillar protein (component 8c-I) from wool is reported. The amino acid composition shows relatively high contents of serine (17 %), half-cystine (14 %), proline (8 %), glycine (8 %) compared to the helical areas of component 8c-I. Although the composition of the cyanogen bromide fragment CNBr-3 resembles the compositions of the high-sulfur proteins extracted from wool there are no obvious sequence homologies present. The Edman degradation yields at an aspartyl-glycyl bond decreased so much that difficulties were encountered in determining the subsequent sequence.