. Author manuscript; available in PMC: 2012 May 1.

Published in final edited form as: Arch Biochem Biophys. 2011 Feb 12;509(1):90–99. doi: 10.1016/j.abb.2011.01.023

TABLE 2.

Primary Deuterium and Solvent Kinetic Isotope Effects for GabD1-catalyzed Reaction^a

parameter	solvent	KIE^b
parameter	solvent	1^st exp.	2^nd exp.
^DV	H₂O	1	1
^DV/K_SSA	H₂O	1.8 ± 0.3	1.5 ± 0.2
^DV/K_NADP+	H₂O	1	1
^DV/K_NADP+^c	H₂O	1.4 ± 0.2	-

^D2OV	H₂O/D₂O	2.4 ±0.1	2.4 ± 0.1
^D2OV/K_SSA	H₂O/D₂O	1	1
^D2OV/K_NADP+	H₂O/D₂O	2.9 ± 0.9	2.8 ± 0.8

^D2OV_[2H]	H₂O/D₂O	2.2 ± 0.1	2.5 ± 0.2
^D2OV/K_([2H]SSA)	H₂O/D₂O	1	1
^D2OV/K_{NADP+ [2H]}	H₂O/D₂O	1.4 ± 0.4	1.6 ± 0.4

^DV	D₂O	1	1
^DV/K_SSA	D₂O	1	1
^DV/K_NADP+	D₂O	0.6 ± 0.1	0.6 ± 0.1

Experiments performed at pH 7.4 and 37°C, in the presence of 10 mM MgCl₂. SSA was kept at 50 μM when NADP⁺ was varied, and NADP⁺ was kept at 200 μM when SSA was varied.

Value ± standard error obtained upon fitting the data to the appropriate equation. For solvent isotope effects experiments were performed in 100% H₂O or 85% D₂O.

SSA concentration was kept at 25 μM.