Biochemical analysis and the preliminary crystallographic characterization of d-tagatose 3-epimerase from Rhodobacter sphaeroides

Table 2 Kinetic parameters of RsDTE wild-type on four substrates

Enzymes	Substrates	K _m (mM)	k _cat (s⁻¹)	k _cat/K _m (s⁻¹ mM⁻¹)	Relative activity (%)
WT	d-Fructose	78 ± 2.3	42.60 ± 0.89	0.55 ± 0.008	100
	d-Psicose	215 ± 4.8	20.47 ± 0.63	0.10 ± 0.005	23.2 ± 1.8
	d-Tagatose	138 ± 0.8	48.31 ± 0.52	0.35 ± 0.006	69.1 ± 2.3
	d-Sorbose	359 ± 3.5	8.30 ± 0.34	0.02 ± 0.001	4.5 ± 0.4
R118W	d-Fructose	162 ± 4.2	41.05 ± 0.43	0.25 ± 0.008	58.46 ± 3.9
	d-Psicose	193 ± 6.2	26.04 ± 0.58	0.14 ± 0.008	22.78 ± 2.7
	d-Tagatose	98 ± 3.5	51.25 ± 0.54	0.52 ± 0.013	100
	d-Sorbose	148 ± 2.8	15.36 ± 0.44	0.10 ± 0.001	16.28 ± 1.6

ISSN: 1475-2859