Table 4. Single turnover catalytic rate constants for Pol β catalyzed nucleotide insertion in free DNA and NCPs.

Substrate	k obs (s-1)	Ratio (DNA/NCP)
DNA-gO (+10)	1.24 ± 0.007
NCP-gO (+10)	0.0005 ± 0.0002	2599.6 ± 1161
DNA-gO (-35)	0.76 ± 0.07
NCP-gO (-35)	0.18 ± 0.07	4.3 ± 1.3
DNA-gI (-49)	0.83 ± 0.17
NCP-gI (-49)	0.003 ± 0.001	276.7 ± 36.6
DNA-g (-60)	5.4 ± 1.1
NCP-g (-60)	0.06 ± 0.008	90.4 ± 6.4

Data represent the mean of three independent experiments ± SD and correspond to data shown in Figure 5 and Figure Supplementary S6.