A comprehensive and comparative study of the internal structure and dynamics of natural β - keratin and regenerated β - keratin by solid state NMR spectroscopy

Structure and dynamics of natural and regenerated chicken feather beta-keratin were investigated by (13)C( )crosspolarization (CP) magic angle spinning (MAS) solid state nuclear magnetic resonance (SSNMR) spectral analysis, C-13 and H-1 spin-lattice relaxation time measurements, and C-13 two dimensional phase adjusted spinning sidebands (2DPASS) MAS SSNMR measurements. Chemical shift anisotropy (CSA) parameters of both natural and regenerated chicken feather beta-keratin were extracted by using 2DPASS MAS SSNMR experiment. The beauty of 2DPASS MAS SSNMR experiment is it can correlate the isotropic and anisotropic dimension with the help of shearing transformation and two dimensional Fourier Transformation. Molecular correlation time at each and every magnetically inequivalent carbon site of both natural and regenerated chicken feather beta-keratin were also determined. The change in molecular dynamics of structural protein after pretreatment was monitored by 2DPASS MAS SSNMR and C-13 relaxation measurement. This type of comprehensive study will provide the information about the interrelation between the structure and dynamics of structural protein and will also shed light in the way of developing methods for conversion of animal by-products to novel product.