Table 2.

DNA-binding affinity of the Trp41 mutants

	$K_{\text{D}}^{\text{DNA}\left(\text{bin}\right)}$ (nM)a	$K_{\text{D}}^{\text{DNA}\left(\text{ter}\right)}$ (pM)b
Trp (WT)	0.25 ± 0.04	0.57 ± 0.14
Ile	0.46 ± 0.10	0.79 ± 0.31
Val	0.13 ± 0.03	0.47 ± 0.14
Phe	0.27 ± 0.08	1.91 ± 0.45
Arg	0.04 ± 0.01	0.72 ± 0.25
Leu	0.53 ± 0.13	0.94 ± 0.83
Ala	0.11 ± 0.05	0.58 ± 0.35
Gly	0.12 ± 0.02	0.62 ± 0.17
Pro	0.16 ± 0.04	1.16 ± 0.77c

^abin, binary complex, MTase-DNA.

^bter, ternary complex, MTase-DNA–AdoHcy.

^cOwing to smearing of the ‘bound DNA’ band, the ‘free DNA’ band alone was used for quantification.