Appendix 3—table 1. Binding of Pol I to flap-containing DNA substrates.

Substrate	$f_B$	$K_d$ ($\mathrm{nM}$)
Double flap	0.28 ± 0.03	13 ± 2
Mixed flap	0.27 ± 0.04	14 ± 3
Downstream flap	0.22 ± 0.03	18 ± 3