Comparative study of the structure of TvNPV polyhedrin and TvNPV virion protein by Raman spectroscopy

Raman spectra were obtained and analysed for polyhedrin and virion protein of Trabala vishnou nuclear polyhedrosis virus (TvNPV‐P and TvNPV‐VP, respectively). It was found that the secondary structures of the protein of the two samples differ: the protein of TvNPV‐P has predominantly an α‐helical and β‐sheet structure whereas that of TvNPV‐P contains predominantly a β‐sheet content, with an α‐helix content and a lower random‐coil or β‐turn content. All tyrosyl residues in the protein of TvNPV‐P are exposed, whereas 80% of the tyrosyl residues are exposed and 20% are buried in the protein of TvNPV‐VP. The majority of the tryptophan residues in the protein of TvNPV‐VP are in a hydrophobic environment. The TvNPV‐VP has a trans‐gauche‐trans configuration of the CCSSCC linkage.