Structure of the X (ADRP) domain of nsp3 from feline coronavirus

Wojdyla, Justyna A.; Manolaridis, Ioannis; Snijder, Eric J.; Gorbalenya, Alexander E.; Coutard, Bruno; Piotrowski, Yvonne; Hilgenfeld, Rolf; Tucker, Paul A.

The structure of the X (or ADRP) domain of a pathogenic variant of feline coronavirus (FCoV) has been determined in tetragonal and cubic crystal forms to 3.1 and 2.2 Å resolution, respectively. In the tetragonal crystal form, glycerol‐3‐phosphate was observed in the ADP‐ribose‐binding site. Both crystal forms contained large solvent channels and had a solvent content of higher than 70%. Only very weak binding of this domain to ADP‐ribose was detected in vitro. However, the structure with ADP‐ribose bound was determined in the cubic crystal form at 3.9 Å resolution. The structure of the FCoV X domain had the expected macro‐domain fold and is the first structure of this domain from a coronavirus belonging to subgroup 1a.