Structural Evaluation of Cytochrome C by Raman Spectroscopy and Its Relationship with Apoptosis and Protein Degradation in Postmortem Bovine Muscle

Structural changes of cytochrome c and its relationship with apoptosis and protein degradation of bovine muscle during postmortem aging were investigated. Results from amide I and amide II ~ VI showed that the π* orbital d electron decreased, the π electron density increased, and the frequency of the C-N stretching vibration increased. The distance between heme Fe and N atoms of the porphyrin decreased, the bond length decreased, and the heme core size decreased. Besides, Fe ligand vibration related Raman bands of cytochrome c had red (right) shift gradually with the extension of aging. The apoptotic rate and the degradation products of desmin and troponin-T were increased (P < 0.05). Correlation analysis results suggested that Fe ligand vibration, not amide I ~ VI related Raman bands were correlated with cytochrome c mediated apoptosis and degradation of myofibrillar protein of bovine muscle during aging.