Selectivity pocket of nairovirus vOTUs.

(A) The CCHFV vOTU Ub bound structure (PDB ID 3PRP) is shown with the location of the selectivity pocket indicated with a box. The selectivity pockets of the other vOTUs are shown, with the Ub (purple) modeled in from the CCHFV structure based on a secondary alignment of the vOTUs. DUGV vOTU (PDB ID 4HXD) is colored silver and ERVEV vOTU (PDB ID 5JZE) is colored brown. The other vOTUs are colored as in Fig 3. All models were generated by aligning the vOTUs with the CCHFV vOTU Ub bound structure in Coot. (B) The extra space (black arrow) existing in the ERVEV-mouse ISG15 structure (PDB ID 5JZE), with the CCHFV vOTU bound to Ub included for comparison (Panel I). QYBV vOTU with Ub and mouse ISG15 (green) modeled in based on vOTU secondary structure alignments, with an arginine also modeled into the space opened up by the mouse ISG15 conformation (Panel II). (C) Activities for Ub-AMC for mutant DGKV, QYBV, and TAGV vOTUs relative to WT. Error bars represent the standard deviation of two independent experiments.