Table 2. Specificity constant values of CcPDH for various monosaccharides.

	Side group orientations in the 1 C 4 conformation a				Kinetic parameters
	C-2	C-3	C-4	C-5	k cat (s-1)	K m (mM)	k cat/K m(×103 s-1M-1)	Relative velocity c
d-glucosone b	E (C-3)	E (C-4)	A (C-5)	- (C-6)	74.1 (±1.4)	7.9 (±0.3)	9.37	100
l-fucose b	E	E	A	E (-CH3)	56.4 (±1.8)	24.8 (±1.2)	2.27	77.7
d-arabinose b	E	E	A	-	35.5 (±0.6)	30.3 (±0.8)	1.17	47.5
l-galactose	E	E	A	E (-CH2OH)	56.1(±1.1)	49.7 (±1.4)	1.13	65.4
d-talose	E	A	E	A (-CH2OH)	17.8 (±0.1)	23.1 (±0.4)	0.77	24.8
l-gulose b	E	A	A	E (-CH2OH)	53.3 (±1.1)	84.7 (±2.6)	0.63	52.1
d-lyxose b	E	A	A	-	12.9 (±0.3)	66.8 (±2.6)	0.19	13.4
l-xylose	E	E	E	-	22.4 (±1.2)	236 (±16)	0.09	11.9
l-glucose	E	E	E	E (-CH2OH)	24.9 (±1.2)	363 (±17)	0.07	9.2
l-lyxose	A	E	E	-	n.d. d	n.d.	-	4.0
l-mannose	A	E	E	E (-CH2OH)	n.d.	n.d.	-	3.6
l-rhamnose	A	E	E	E (-CH3)	n.d.	n.d.	-	0.7

^a Carbon numbers of d-glucosone in brackets; E, equatorial bond; A, axial bond.

^b Data for the kinetic parameters are taken from Ref. (5).

^c The velocity with each substrate is expressed relative to 100 for the velocity with d-glucosone. The initial substrate concentration was 30 mM d-glucosone and 100 mM the others monosaccharides.

^d n.d., not determined.