Table 1.

Relative substrate processing efficiencies of WT and mutant variants of ROS1^a

ROS1 variant	5-meC:G			T:G
	Pmax (nM)	T50 (h)	Erel	Pmax (nM)	T50 (h)	Erel
WT	10.24 ± 0.17	3.30	3.10 ± 0.05	7.64 ± 0.18	4.83	1.58 ± 0.04
Q584L	12.23 ± 0.45	5.07	2.41 ± 0.09	9.93 ± 0.51	5.42	1.83 ± 0.09
F589A	1.84 ± 0.11	5.10	0.36 ± 0.02	3.22 ± 0.21	4.76	0.68 ± 0.04
T606L	n.d.b	n.a.c	n.a.	n.d.	n.a.	n.a.
Q607A	1.19 ± 0.09	2.63	0.45 ± 0.04	0.29 ± 0.04	0.62	0.48 ± 0.06
N608A	13.64 ± 0.35	4.73	2.88 ± 0.07	12.07 ± 0.33	9.38	1.29 ± 0.04
D611V	n.d.	n.a.	n.a.	n.d.	n.a.	n.a.
W1012A	7.99 ± 0.27	5.01	1.60 ± 0.06	5.41 ± 0.45	6.62	0.82 ± 0.07
Y1028S	7.76 ± 0.22	5.11	1.50 ± 0.04	10.87 ± 0.62	5.66	1.92 ± 0.11

^aPurified proteins (20 nM) were incubated at 30°C with 51-mer double-stranded oligonucleotide substrates (20 nM) containing either a single 5-meC:G pair or a T:G mispair. Reaction products were separated in a 12% denaturing polyacrylamide gel and quantified by fluorescence scanning. Shown are the plateau levels of substrate nicking (P_max) and the time required for processing of 50% of P_max (T₅₀). Relative processing efficiency was calculated as E_rel = P_max/T₅₀. Values are mean ± SE from two independent experiments.

^bn.d., none detected.

^cn.a., not applicable.