Table 1.

Steady-state kinetic constants of POLN and mutant derivatives

DNA substrate	enzyme	dNTP	Km (µM)	kcat (min−1 × 10−4)	kcat/Km (µM−1 min−1 × 10−4)	finc
Insertion opposite G	WT	dCTP	7.5 ± 0.3	959 ± 50	128 ± 12	1
5′-ATG-TACGTC		dTTP	18.5 ± 1.5	899 ± 101	49.3 ± 9.4	3.9 × 10−1
	delPa	dCTP	8.2 ± 0.6	987 ± 28	124 ± 43	1
		dTTP	18.8 ± 4.6	928 ± 20	55.2 ± 2.4	4.5 × 10−1
	K679R	dCTP	8.1 ± 0.2	549 ± 23	67.5 ± 1.0	1
		dTTP	19.8 ± 1.7	507 ± 19	25.6 ± 5.2	3.8 × 10−1
	K679T	dCTP	5.7 ± 0.6	473 ± 67	83.5 ± 8.8	1
		dTTP	43.2 ± 1.5	171 ± 30	4.0 ± 0.8	4.8 × 10−2
	K679A	dCTP	7.8 ± 0.8	588 ± 104	78.1 ± 26	1
		dTTP	52.1 ± 3.3	227 ± 47	4.4 ± 1.2	5.6 × 10−2
	Y682F	dCTP	32.8 ± 3.5	157 ± 12	4.9 ± 0.9	1
		dTTP	98.6 ± 11.6	42.5 ± 8.0	0.4 ± 0.0	8.2 × 10−2
DNA substrate	enzyme	dNTP	Km (µM)	kcat (min−1 × 10−4)	kcat/Km (µM−1 min−1 × 10−4)	Relative efficiencyb
Insertion opposite T	WT	dATP	8.5 ± 1.4	1265 ± 91	152 ± 14
5′-ATG-TACTTC	delPa	dATP	7.0 ± 1.4	1385 ± 212	201 ± 9
	K679R	dATP	8.8 ± 1.0	1402 ± 219	165 ± 43
	K679T	dATP	6.8 ± 0.1	410 ± 10	60.2 ± 2.6
	K679A	dATP	7.4 ± 0.4	695 ± 96	92.8 ± 7.9
	Y682F	dATP	26.2 ± 1.3	220 ± 38	8.4 ± 0.6
Insertion opposite 5S-Tg	WT	dATP	14.2 ± 1.5	346 ± 24	24.7 ± 4.3	1.6 × 10−1
5′-ATG-TACTgTC	delPa	dATP	11.8 ± 1.1	392 ± 15	33.5 ± 2	1.7 × 10−1
	K679R	dATP	13.0 ± 0.1	361 ± 9	27.8 ± 0.8	1.7 × 10−1
	K679T	dATP	28.6 ± 1.1	132 ± 10	4.6 ± 0.5	7.6 × 10−2
	K679A	dATP	36.2 ± 1.0	167 ± 11	4.6 ± 0.2	5.0 × 10−2
	Y682F	dATP	126 ± 20	156 ± 14	1.2 ± 0.2	1.4 × 10−1

^aData were taken from ref. (1).

^bk_cat/K_m values for incorporation of dATP were normalized to 1 and the k_cat/K_m values were given relative to these values.