Fig. 2.

Crystal structure of dimeric VP30_CTD. (A) Stereo image of the experimental electron-density map obtained from single-wavelength anomalous dispersion phases and noncrystallographic symmetry averaging showing the hydrophobic core of VP30. (B) Ribbon representation of the VP30_CTD monomer that is dominated by a compact core composed of six helices and a seventh helix pointing away from the core. Secondary-structure elements are indicated. (C) Ribbon representation of the VP30_CTD dimer in yellow and red. Head-to-head dimerization is supported by helix 7 interactions with the neighboring core of VP30_CTD. Both N termini point away from the same side of the dimer and could potentially link up to form parallel hexamers as formed by VP30_89–272 in vitro and VP30 present in EBOV particles. (D) Closeup of the VP30_CTD dimerization interface. Residues mediating polar interactions are shown as all-atom model. Note that most of the interactions are between helix 7 and the loop region connecting helices 6 and 7 and the opposing helix 1.