TABLE 2.

Enzymatic properties of CnThrDH WT and variants

Variantsa	kcatb	Km, l-Thrc	Km, NAD+c	kcat/Km, l-Thr
	s−1	mm	mm	s−1 mm−1
WT	50.0 ± 3.7	15.2 ± 2.6	0.120 ± 0.020	3.3
L80G	NDd	ND	0.115 ± 0.003	0.001
G184A	ND	ND	0.156 ± 0.012	0.01
T186N	ND	ND	0.097 ± 0.004	0.01

^a Locations of mutated sites in the three-dimensional structure are shown in Fig. 5A. Recombinant enzymes were purified as described under “Experimental Procedures.”

^b k_cat values of the variants and WT were derived from the data shown in Fig. 5 (B and C).

^c K_{m, l}-Thr and K_{m, NAD}⁺ values represent the Michaelis constant value toward l-Thr and NAD⁺, respectively.

^d ND, not determined.