220-MHz Proton Magnetic Resonance Spectra of Homogeneous High-Sulphur Fractions of Reduced Wool

Dale, B.J.; Jones, D.W.

220-MHz Proton Magnetic Resonance Spectra of Homogeneous High-Sulphur Fractions of Reduced Wool

1974

Dale, B.J. | Jones, D.W.

High-resolution proton magnetic resonance spectra have been recorded at 220 MHz from aqueous solutions of the effectively homogeneous reduced wool fractions S-carboxymethyl keratein (SCMK) B-IIIB2 (the first keratin protein to have been sequenced) and SCMKB-IIIB4. Spectral assignments on the basis of amino acid composition and of known amino acid, peptide, and protein spectra are confirmed by simulation of the experimental spectrum of SCMKB-IIIB2. Absence of appreciable spectral change with temperature is consistent with predominance of unordered conformation. For spectra in trifluoracetic acid solution (which do not suffer from masking by solvent), small downfield shifts are attributed to protonation of side-chain groups.

Показать больше [+]