Figure 1
The SARS-CoV PLpro C112S mutant forms a stable complex with Ub. (a) Traces of absorbance at 280 nm of the PLpro C112S mutant in 50 mM phosphate buffer pH 7.4 during the sedimentation-velocity experiment. The protein concentration was 0.2 mg ml−1. For clarity, only every third scan is shown. The circles represent experimental data and the lines are the results obtained after fitting to the Lamm equation using SEDFIT (Chou et al., 2011; Schuck, 2000). (b), (c) and (d) show the continuous c(s) distributions of PLpro C112S mutant (0.2 mg ml−1), Ub (1 mg ml−1) and C112S mutant with Ub (8 and 2 mg ml−1), respectively. The two vertical dotted lines indicate the positions of PLpro (s = 2.72) and Ub (s = 1.04) alone. The residual bitmaps of the raw data and the best-fit results are shown in the insets. |