Figure 6.

Relationships between the tyrosine ratio R_F, representing the degree of alkalinity and hydrophobicity, of the virion surface and (a) β-sheet protein fraction, R_βs, (b) random coil protein fraction, R_rc, (c) band shift for the Trp indole ring deformation band found at 878 cm^–1 for neutral pH, and (d) relative areal fraction, R_phe, covered by the symmetric benzene ring breathing vibration of Phe at 1005 ± 3 cm^–1 with respect to the cumulative area of Raman scatter in the spectral region between 600 and 1800 cm^–1. The consistency among the plots (a–d) represents a cross-parametric check for the evolutional trends of the Omicron subvariants toward increasingly alkaline and hydrophobic surface-protonation conditions.