Table 4.

The effect of 2′-deoxy-methylphosphonate substitutions in the 3'-strand of human tRNA^Pro on aminoacylation efficiency

Variant	Relative kcat/KM (±SD)	Activity change (x-fold)	−ΔΔG‡ (kcal/mol)	(−ΔΔG‡)Me a (kcal/mol)
WT	1.00	1.0	0.0	0.0
dC75Me	0.28 (±0.05)	−3.6	0.76	−0.41
dC74Me	0.23 (±0.05)	−4.3	0.87	−0.19
dC73Me	0.14 (±0.07)	−7.3	1.17	−0.30
dC72Me	0.11 (±0.03)	−8.8	1.29	0.55
dC71Me	0.05 (±0.02)	−18.5	1.73	1.66
dG70Me	0.06 (±0.03)	−17.0	1.68	1.50
dA69Me	0.77 (±0.05)	−1.3	0.16	−0.13
dG68Me	0.80 (±0.04)	−1.2	0.13	−0.35
dC67Me	0.16 (±0.03)	−6.2	1.08	0.40
dA66Me	0.13 (±0.08)	−7.8	1.22	−0.51
dG65Me	0.29 (±0.15)	−3.5	0.74	−0.18
dG64Me	0.38 (±0.12)	−2.6	0.57	−0.26
dC63Me	0.26 (±0.07)	−3.8	0.80	0.20

The reported k_cat/K_M and −ΔΔG^‡ values were obtained as described in the legend to Table 1.

^aThe (−ΔΔG^‡)^Me value corresponds to the corrected value obtained by subtracting the contribution of the 2′-deoxynucleotide substitution as described in the text (Table 1).