. Author manuscript; available in PMC: 2016 Apr 1.

Published in final edited form as: FEBS J. 2015 Mar 23;282(8):1445–1457. doi: 10.1111/febs.13232

Table 1.

Thermal Stability and Catalytic Measurements

Enzyme	T_M (°C)^a	k_cat^ex/K_eff^S (M⁻¹µs⁻¹)^b	k_B (µs⁻¹)^c	pK_a ZnOH⁻^c	pK_a His64^c
wild-type HCA II	57.1 (± 0.1)	120 (± 5)	1.2 (±0.2)	6.9 (± 0.1)	7.2 (± 0.1)
K170P	55.7 (± 0.1)	63 (± 3)	1.4 (±0.3)	6.7 (± 0.1)	6.4 (± 0.1)
E234P	57.9 (± 0.1)	56 (± 2)	3.1 (± 0.6)	7.2 (± 0.1)	6.2 (± 0.1)
Δ230–240	58.9 (± 0.2)	66 (± 3)	1.0 (± 0.6)	6.7 (± 0.2)	5.8 (± 0.2)

Denaturation temperature as determined from Fig. 1 and Eq. 3.

Catalytic efficiency determined from the fit in Fig. 2A and Eq. 8

Proton transfer rate and ionization constants determined from the fit in Fig. 2B and Eq. 9