Figure 3.

FLCS_Spike docked onto Furin and stabilized by Spike–Furin interfacial salt-bridges (in RR1_CoV-2). The figure maps the docked FLCS_Spike (loop, highlighted in yellow, flanked at either end by beta-strands colored in cyan) at the Furin docking site in RR1_CoV-2 while the rest of the Spike that is visible in this closeup view is in a combined dots and cartoon display (the later of the two only chosen for the interacting Spike chain). A direct visual comparison can be made between Figure 2 and Figure 3, wherein the former of two portrays the proposed dockable surface groove (see corresponding main-text, Section 3.4) near the Furin catalytic triad and the latter shows the docked FLCS_Spike (as it occurred) at the very groove, surrounded by anionic residues amenable to form salt-bridges with the FLCS_Spike arginines (R682, R683, R685). In consistency with Figure 2 the triad-proximal Furin anionic residues are labeled with font color white while the triad-residues are labeled in black.