. Author manuscript; available in PMC: 2008 Sep 25.

Published in final edited form as: Biochemistry. 2007 Jun 27;46(29):8603–8610. doi: 10.1021/bi700597p

Table 3.

Kinetic constants for α-thrombin cleaving soluble PAR exodomains.

	K_m (μM)^a	k_cat (s^-1) ^a	k_cat/K_m (M^-1×s^-1)^b	k_cat/K_m (M^-1×•s^-1)^c
PAR1-wt	28 ± 8.8	340 ± 36	1.2 ×10⁷	1.1 ×10⁷
PAR1-L38A	29 ± 11	47 ± 9.2^d	1.7 ×10⁶	3.5 ×10⁶
PAR1-D39A	10 ± 3.4^d	140 ± 20^d	1.4×10⁷	1.3 ×10⁷
PAR1-P40A	23 ± 7.8	230 ± 26^d	9.9×10⁶	9.1 ×10⁶
PAR4-wt	61 ± 24	17 ± 2.3	2.8 ×10⁵	4.1 ×10⁵
PAR4-L43A	69 ± 28	9.7 ± 1.6^d	1.4 ×10⁵ ^d	2.1 ×10⁵ ^d
PAR4-P44A	56 ± 22	7.7 ± 1.1^d	1.5 ×10⁵ ^d	2.5 ×10⁵ ^d
PAR4-P46A	72 ± 32	0.64 ± .08^d	8.9 ×10³ ^d	7.9 ×10³ ^d

10 mM Tris·HCl, 150 mM NaCl, pH 8.0, 37°C

± 95% confidence interval

determined by direct measurement of k_cat and K_m

determined by: [S] = [S] ₀exp(-se_Tt) at [S] ≪ K_m

p < 0.05 compared to wild type sequence