Table 1.

Pathway radicals trapped in E. coli class Ia RNR by site-specifically incorporating unnatural amino acids or reaction with N₃UDP; PELDOR distances (< ± 1 Å) are given in last column. ● corresponds to forward RT and ● to reverse RT, as indicated by the direction of the arrows on the pathway shown below the table.

α	β	Y₁₂₂	Y₃₅₆	Y₇₃₁	Y₇₃₀	C₄₃₉	NDP	Y₁₂₂•-X• distance (Å)
WT	WT	●/●	-	-	-	-	-	33
WT	DOPA₃₅₆	-	●	-	-	-	-	30
WT	NH₂Y₃₅₆	-	●	-	-	-	-	30
Y₇₃₁F	F₃Y₁₂₂	-	●	-	-	-	-	30
NH₂Y₇₃₁	WT	-	-	●	-	-	-	38
NH₂Y₇₃₁/R₄₁₁A	WT	-	-	●	-	-	-	35
NH₂Y₇₃₀	WT	-	-	-	●	-	-	39
WT	WT	-	-	-	-	-	N₃UDP●	48
WT	F₃Y₁₂₂	-	●	-	-	-	-	30
WT	NO₂Y₁₂₂	-	●	-	-	-	-	30