Qualitative analysis of polyUb chain hydrolysis by CCHFV L protein and the isolated CCHFV OTU domain.

Purified CCHFV L protein (RdRp) was incubated with either (A) K⁴⁸polyUb or (B) K⁶³polyUb chains in the presence or absence of OTU-specific inhibitor CC.4. Ub chain hydrolysis was also assessed for the purified OTU domain using (C) K⁴⁸polyUb chains or (D) K⁶³polyUb chains in the presence or absence of CC.4. Reactions were incubated at 37°C and samples taken at 0, 15 and 30 minutes as indicated. Ub chain lengths following digestion are indicated with arrows. Samples were resolved on a 10% tris-tricine gel and visualized by silver stain.