title: Spectroscopic study of conformational changes accompanying self-assembly of HCV core protein.
abstract: Electron microscopy and infrared and Raman spectroscopy have been used here to study the morphology, size distribution, secondary and tertiary structures of protein particles assembled from a truncated hepatitis C virus (HCV) core protein covering the first 120 aa. Particles of pure protein, having similar morphology and size distribution of those of nucleocapsids found in sera from HCV-infected patients, have been visualized for the first time. The secondary structure of these protein particles involve beta-sheet enrichment in relation to its protein monomer. Tertiary/quaternary structure has also been studied using the dynamics of H/D exchange. With this aim infrared spectra were measured as a function of H/D exchange time and subsequently analyzed by principal component analysis and two-dimensional correlation spectroscopy. Temporal dynamics of exchange for these protein particles were as follows: arginine residues exchanged first, followed by turn and unordered structures, followed by beta-sheets which may act as linkers of protein monomers.
authors.affiliation: Instituto de Estructura de la Materia (CSIC), Serrano 121, 28006 Madrid, Spain.
authors.forename: Arantxa
authors.initials: A
authors.lastname: Rodríguez-Casado
authors.forename: Marina
authors.initials: M
authors.lastname: Molina
authors.forename: Pedro
authors.initials: P
authors.lastname: Carmona
mesh_terms: D001120:Arginine / Q000378:metabolism; D002942:Circular Dichroism; D041961:Deuterium Exchange Measurement; D019281:Dimerization; D008854:Microscopy, Electron; D008958:Models, Molecular; D019251:Nucleocapsid / Q000737:chemistry / Q000378:metabolism; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D014758:Viral Core Proteins / Q000737:chemistry* / Q000378:metabolism; D019065:Virus Assembly
chemical_list: D011994:Recombinant Proteins; D014758:Viral Core Proteins; C069130:nucleocapsid protein, Hepatitis C virus; D001120:Arginine