Binding of transmissible gastroenteritis virus and porcine respiratory coronavirus to human and porcine aminopeptidase N receptors as an indicator of cross-species transmission
Fig 2
Comparison of amino acid sequences of the S-protein RBD regions among TGEV, PRCV, and other coronaviruses.
Conservation of amino acid substitutions in TGEV and PRCV strains was assessed using Grantham’s distances: conservative (green, 0–50), moderately conservative (yellow, 51–100), moderately radical (orange, 101–150), and radical (red, ≥ 151). Identical substitutions in other coronaviruses were similarly color-coded. The RBD region spans residues 522–671 in the reference TGEV Purdue strain. Residue S522 is omitted due to a gap in multiple alignment with sequences from other coronavirus species; details on substitutions and Grantham’s distances are provided in S2 Table.