Figure 7.

Comparison of Tm MiaB activity with dithionite‐reduced ferredoxin at 65°C. MiaB activity was determined in reactions in which dithionite‐reduced ferredoxin was supplied as reductant in the absence of ferredoxin–reductase and NADPH. Shown are MiaB reactions with (A) TM0927, (B) TM1289, (C) TM1175, (D) TM1533, and (E) TM1815, indicating the formation of ms²i⁶A (black squares), 5′‐dA (red triangles), and SAH (blue circles) and loss of i⁶A green squares) at specific time points. Reactions were conducted at 65°C and contained the following in a 100 μL volume: 50 μM Tm MiaB, 100 μM i⁶A tRNA^Phe, 1 mM SAM, 150 μM dithionite‐reduced Tm ferredoxin, and buffer system (50 mM HEPES (pH 7.5), 150 mM KCl, 1 mM MgCl₂, and 686 μM L‐(+)‐tryptophan as an internal standard).