Fig. 6: Subparticle reconstruction and interaction analysis of HPV16:001 immune complex.

(a) The cryo-EM structures of twofold axis subparticle region was surface colored according to the local resolution ranging from 3 to 7 Å. (b) Close-up view of the L1 monomer and the bound Fab density map, which was fitting with the corresponding models in ribbon diagram excluding the Fab constant domain. (c) Electron density maps from the segment of Fab and capsid. (d) One icosahedral asymmetric unit of H16-001 structure with a monomer and its bound Fab. (e) The footprints of Fab H16.001, of which the dashed box indicated the different L1 monomers with Fab H16.001 interaction. (f) 2D projection of H16.001 footprints on HPV16 surface produced by RIVEM. The footprints are highlighted and colored according to the distance of particle surface to Fab from red to blue. One icosahedral asymmetric of HPV16 is shown in a black triangle. (g–i) Close-up views of the chain-D (g), chain-C (h), and chain-E (i) with capsid interaction. The potential hydrogen bonding and salt bridges in interaction sites were labeled and marked by yellow dashed lines. The different chains in one icosahedral asymmetric unit were colored in the same scheme as follows: chain-A in pale green, chain-B in light chain, chain-C in light pink, chain-D in pale yellow, chain-E in light orange, chain-F in gray, heavy chain in cyan, and light chain in magenta.