Table 1.

Steady-state kinetic characterization of full-length and separated ANT(3”)-Ii/AAC(6′)-IId

Activity	Substrate	Km (μM)	kcat (s−1)	kcat/Km (M−1s−1)	kcatfull / kcatfrag	kcat/Kmfull / kcat/Kmfrag
NHis6-tagged AAC(6′)-IId
Acetyltransferase	AMK*	127 ± 6	7.09 ± 0.53	6.24 ± 0.53 × 104	0.412	84.1
	GEN	14.3 ± 2.3	3.33 ± 0.14	2.34 ± 0.39 × 105	0.333	0.940
	KAN	16.0 ± 1.7	2.13 ± 0.06	1.33 ± 0.15 × 105	1.79	14.2
	NEO	32.1 ± 11.1	11.1 ± 1.0	3.46 ± 1.24 × 105	0.816	1.14
	NET	3.87 ± 0.90	3.21 ± 0.20	8.29 ± 2.00 × 105	0.595	1.30
	RIB	69.3 ± 4.5	5.70 ± 0.12	8.22 ± 0.56 × 104	0.681	2.96
	SIS	4.92 ± 1.14	5.35 ± 0.27	1.09 ± 0.26 × 106	0.548	1.22
	TOB	14.8 ± 3.4	3.73 ± 0.25	2.52 ± 0.60 × 105	1.03	1.92
	AcCoA	147 ± 36	12.1 ± 1.6	8.20 ± 2.29 ×104	0.132	0.102
NHis10-tagged ANT(3”)-Ii/AAC(6′)-IId
Acetyltransferase	AMK	0.556 ± 0.130	2.92 ± 0.10	5.25 ± 1.25 × 106
	GEN	5.04 ± 0.65	1.11 ± 0.03	2.20 ± 0.29 × 105
	KAN	2.02 ± 0.41	3.81 ± 0.15	1.89 ± 0.39 × 106
	NEO	23.0 ± 4.8	9.06 ± 0.4	3.94 ± 0.84 × 105
	NET	1.77 ± 0.41	1.91 ± 0.08	1.08 ± 0.25 × 106
	RIB	16.0 ± 3.9	3.88 ± 0.29	2.43 ± 0.63 × 105
	SIS	2.20 ± 0.60	2.93 ± 0.16	1.33 ± 0.37 × 106
	TOB	7.92 ± 0.53	3.84 ± 0.07	4.85 ± 0.34 × 105
	AcCoA*	215 ± 25	1.62 ± 0.02	8.38 ± 1.09 × 103
Nucleotidyltransferase	SPT	0.159 ± 0.007	0.748 ± 0.007	4.70 ± 0.21 × 106
	ATP	27.9 ± 4.1	0.753 ± 0.040	2.70 ± 0.42 × 104
	dATP	20.9 ± 1.6	0.405 ± 0.010	1.94 ± 0.16 × 104
	CTP*	131 ± 28	0.531 ± 0.064	4.04 ± 0.99 × 103
	dCTP*	166 ± 19	1.11 ± 0.01	6.70 ± 0.76 × 103
	ITP	30.6 ± 2.6	0.148 ± 0.004	4.83 ± 0.43 × 103
	UTP*	105 ± 6	0.526 ± 0.014	5.02 ± 0.32 × 103
	dUTP	74.7 ± 6.5	0.535 ± 0.022	7.16 ± 0.69 × 103
CHis6-tagged ANT(3”)-Ii
Nucleotidyltransferase	SPT	0.123 ± 0.015	5.13 ± 0.11	4.15 ± 0.51 × 107	0.147	0.113
	ATP	8.50 ± 1.46	1.15 ± 0.07	1.35 ± 0.25 × 105	0.655	0.200
	dATP	4.48 ± 1.15	0.508 ± 0.035	1.13 ± 0.30 × 105	0.797	0.172
	CTP	33.3 ± 5.6	0.709 ± 0.040	2.13 ± 0.38 × 104	0.749	0.190
	dCTP*	121 ± 6	0.667 ± 0.007	5.48 ± 0.27 × 103	1.66	1.22
	ITP	12.6 ± 1.5	0.481 ± 0.013	3.81 ± 0.45 × 104	0.308	0.127
	UTP	26.2 ± 5.7	0.603 ± 0.047	2.30 ± 0.53 × 104	0.872	0.218
	dUTP	46.1 ± 6.4	0.565 ± 0.031	1.23 ± 0.18 × 104	0.947	0.582

^*Indicates that the kinetic parameters were in these rare instances determined by Lineweaver-Burk instead of Michaelis-Menten.

Full = ANT(3”)-Ii/AAC(6′)-IId

Frag = ANT(3”)-Ii or AAC(6′)-IId