TABLE 2.

hPol δ catalysis of nucleotide addition during correct and incorrect incorporation

Primer extension experiments measured incorporation of dCTP or dTTP across from template G. S.D. reflect three replicate experiments.

	Pol δD400A	Pol δDQ	Fold (DQ:D400A)
Correct (dCTP-G)a
Vmax (fmol/min)	18 ± 0.13	26 ± 1.2
Km (μm)	0.25 ± 0.01	2.5 ± 0.4
kcat (min−1)	0.51 ± 0.004	0.19 ± 0.009
kcat/Km	2	0.076	−26
Incorrect (dTTP-G)b
Vmax (fmol/min)	38 ± 11	9.1 ± 0.98
Km (μm)	340 ± 180	180 ± 43
kcat (min−1)	0.39 ± 0.11	0.027 ± 0.002
kcat/Km	0.001	0.0001	−10
finc*c	0.0005	0.0013	2.6

^a Correct incorporation experiments used 0.14 pmol hPol δ^DQ and 0.036 pmol hPol δ^D400A.

^b Incorrect incorporation experiments used 0.336 pmol hPol δ^DQ and 0.099 pmol hPol δ^D400A.

^c f_inc given by (k_cat/K_m)^incorrect/(k_cat/K_m)^correct.