Fig 8. Mutation of L143 or C133 does not affect activity towards differently linked ubiquitin. Wild-type L pro and the L pro mutants (C133S, L143A) were incubated with each of the eight di-ubiquitin chain types for the indicated times, separated by SDS-PAGE, and visualized by silver-staining. The concentration of L pro used in the cleavage assays is indicated. https://doi.org/10.1371/journal.ppat.1008702.g008