Table 4.

Predicted FRET efficiencies based on distances between SgrAI–(PC DNA)₂ complexes

Relationship between Rox and neighboring Floa	Distance between fluorophores	Calculated efficiencyb
	Å
N and N + 1 (or N − 1)	72.8	0.157
N and N + 1 (or N − 1)	105.6	0.020
N and N + 1 (or N − 1)	92.9	0.027
N and N + 2 (or N − 2)	76.5	0.12
N and N + 3 (or N − 3)	32	0.96

^a Rox and Flo refer to SgrAI–DNA complexes bound to Rox- or Flo-labeled DNA, respectively.

^b FRET efficiency calculated from the equation efficiency = 1/(1 + (r/R₀)⁶). A value of 51 Å was used for R₀ (44). The combined total for N to N + 1 (or N − 1) is the sum of the three values, giving 0.2.