. Author manuscript; available in PMC: 2015 Dec 11.

Published in final edited form as: Biochemistry. 2010 Aug 3;49(30):6451–6461. doi: 10.1021/bi100769k

Table 4.

Steady-State Kinetic Parameters for Cleavage of AP- and F-Substrates by Wild-Type and Mutant APE1

enzyme/substrate	K_M (nM)	k_cat (s⁻¹)	k_cat/K_M (M⁻¹ s⁻¹)	K_M^SF (nM)^a	k_cat^SF (s⁻¹)	k_cat ^SF/K_M ^SF (M⁻¹ s ⁻¹)
WT APE1/AP	93	2.8	3 × 10⁷	55	1.25	2.27 × 10⁷
WT APE1/F	98	1.0	1×10⁷	46	0.6	1.3 × 10⁷
mutant APE1/AP	220	1.53 × 10⁻⁴	0.63 × 10³

Values of K_M^SF, k_cat^SF, and k_cat^SF/K_M^SF were calculated from the presteady-state kinetic parameters using graph theory approach (see Results).