. Author manuscript; available in PMC: 2013 Dec 18.

Published in final edited form as: Biochemistry. 2012 Dec 4;51(50):10075–10086. doi: 10.1021/bi3009104

Table 1.

Kinetic rate constants for USP2

Substrate	k_cat (s⁻¹)	K_m (μM)	k_cat/K_M (M⁻¹s⁻¹)	k₁ (μM⁻¹s⁻¹)	k₋₁ (s⁻¹)	k₂ (s⁻¹)	k₋₂ (s⁻¹)	K_d,app (μM)
Ubiquitin	N/A	N/A	N/A	0.40 ± 0.01	2.64 ± 0.56	N/A	N/A	ND
Ub-AMC	0.35 ± 0.03	2.4 ± 0.2	1.5 × 10⁵	0.33 ± 0.02^*	1.82 ± 0.17^*	N/A	N/A	2.9 ± 0.6 ^*
IQF-diubiquitin (K48)	0.10 ± 0.01	1.2 ± 0.1	8.3 × 10⁴	0.14 ± 0.01^*	0.06 ^*	0.21 ^*	0.36 ^*	0.27 ± 0.08 ^*
Native diubiquitin (K48)	0.19 ± 0.01	2.8 ± 0.3	6.8 × 10⁴	0.23 ± 0.01 ^*	0.06^*	ND	ND	ND

Indicates the constant was derived using the USP2 C276A mutant. ND stands for not determined and N/A stands for not applicable