. Author manuscript; available in PMC: 2010 Feb 10.

Published in final edited form as: Biochemistry. 2009 Feb 10;48(5):951–959. doi: 10.1021/bi802094k

Table 2.

Kinetic Parameters for PutA86-630, Y540S and Y540A^a

Enzyme	Substrate	K_m (M)	k_cat (s⁻¹)	k_cat/K_m (s⁻¹M⁻¹)	Preference for proline^b	K_i for THFA (mM)
PutA86-630	proline	0.059 ± 0.003	29. ± 1.	492	164	0.084 ± 0.003
PutA86-630	hydroxyproline	0.75 ± 0.05	2.5 ± 0.1	3	-	-
Y540S	proline	0.10 ± 0.01	7.8 ± 0.4	78	7	1.5 ± 0.1
Y540S	hydroxyproline	0.19 ± 0.01	2.0 ± 0.1	11	-	-
Y540A	proline	0.52 ± 0.03	13. ± 1.	25	3	7.9 ± 0.5
Y540A	hydroxyproline	0.31 ± 0.01	2.9 ± 0.1	9	-	-

Enzyme assays were performed at 25°C.

Defined as (k_cat/K_m) for proline divided by (k_cat/K_m) for hydroxyproline.