Fig. 3.

Effect of capreomycin and viomycin on misreading during translation elongation. Drug-induced misreading was quantified using the Arg245 (CGC) near-cognate mutant of firefly luciferase (filled circles, capreomycin [Capr]; filled squares, viomycin [Vio]). The Arg245 (AGA) noncognate mutant of firefly luciferase was used as a misreading control (open circles, capreomycin [Capr]; open squares; viomycin [Vio]). Bacterial ribosomes, mitohybrid ribosomes, mutant 1555G mitohybrid ribosomes, and mutant C1494U mitohybrid ribosomes are indicated. Misreading was calculated by comparing mutant firefly/Renilla luciferase activity to wild-type His245 (CAC) firefly/Renilla luciferase activity. The IC₅₀ inhibitory values (drug concentrations which inhibit protein synthesis to 50%) are indicated; for a comparison, see Table 2.