FIG. 8.

HPLC profiles of 4-thiouridine (s⁴U) region at 330 nm of strain CL100 (ΔiscS) grown in rich medium supplemented with sulfide. (Top) Profile from parent strain MC1061, which shows typical levels of 4-thiouridine. (Middle) tRNA nucleoside profile from strain CL100 grown in LB only. (Bottom) Profile from CL100 grown in LB supplemented with 5 mM sodium sulfide (HS⁻). Residual peaks from the large amounts of C, U, and G are visible for comparison between the three profiles. A similar amount of digested tRNA was loaded for each run shown.