. Author manuscript; available in PMC: 2008 Jan 18.

Published in final edited form as: J Am Chem Soc. 2007 Jun 26;129(28):8714–8715. doi: 10.1021/ja0734391

Table 2.

Kinetic parameters for nucleoside analogs at 37°C

substrate	K_M (μM)	k_cat (s⁻¹)	k_cat/K_M × 10⁴ (M⁻¹ s⁻¹)	relative activity	preferred conform.
dU	1.5 ± 1	0.7 ± 0.1	48	0.8	C_2′ -endo
U	> 1000	n.d.	-	-	C_3′ -endo
5-FdUrd	1 ± 0.1	0.74 ± 0.05	74	2.5	C_2′ -endo
ddT	30 ± 5	0.33 ± 0.04	1.1	1.1	C_2′ -endo
ddU	> 1000	n.d.	-	-	C_3′ -endo
AZT	0.65 ± 0.2	0.29 ± 0.03	45	1	C_3′ -endo
d4T	75 ± 5	0.41 ± 0.02	0.54	1.4	planar
DOT	114 ± 15	0.29 ± 0.02	0.25	1	C_3′ -endo
L-FMAU	132 ± 4	0.5 ± 0.02	0.38	1.7	C_2′ -endo
L-T	> 1000	n.d.	-	-	C_2′ -endo

n.d. = not determined as v_max was not reached at 1000 μM substrate. dU: 2′-deoxyuridine, U: Uridine, ddT: 2′3′-dideoxythymidine, ddU: 2′3′-dideoxyuridine, 5FdUrd: 5-fluoro-2′-deoxyuridine, AZT: 2′,3′-dideoxy-3′-azidothymidine, d4T: 2′,3′-dideoxy-2′,3′-didehydrothymidine, L-FMAU: 2′-fluoro-5-methyl-β-L-arabinofuranosyluracil, L-T: L-thymidine, DOT: dioxolane thymidine