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. 2012 Sep;78(17):6161–6171. doi: 10.1128/AEM.01503-12

Table 2.

Apparent kinetic constants of CDH IIA and CDH IIB for electron donors determined with 1,4-benzoquinone (1 mM) in McIlvaine buffer at pH 6.0^c

Carbohydrate	CDH IIA			CDH IIB
Carbohydrate	K_m (mM)	k_cat (s⁻¹)	k_cat/K_m (mM⁻¹ s⁻¹)	K_m (mM)	k_cat (s⁻¹)	k_cat/K_m (mM⁻¹ s⁻¹)
Cellobiose	0.090	45.8	508	0.022	11.4	527
Cellotriose	0.230	49.7	216	0.045	12.4	278
Cellotetraose	0.204	46.0	226	0.061	11.6	189
Cellopentaose	0.196	46.6	238	0.043	10.2	238
Lactose	0.290	49.3	170	0.089	11.8	133
Maltose	17.2	0.4	0.023	3.44	3.5	1.02
Maltotriose	34.3	1.8	0.053	1.2	1.0	0.8
Maltotetraose	35.7	2.2	0.061	4.5	1.4	2.74
Glucose	3,700^a	55^a	0.015	550	8.1	0.014
Galactose		1.5^b		3,600^a	3.6^a	0.001
Mannopentaose	39.2	19.8	0.506	8.4	7.4	0.88
Mannose	10,000^a	4.7	0.0004	13,300^a	4.3	0.0003
Xylobiose	3.6	45.4	12.8	1.31	5.8	4.45
Xylotriose	3	6	2	0.81	2.3	2.8
Xylose	2,770^a	1.5	0.0005	1,545^a	1.9	0.0012
Arabinose		0.1^b		3,200^a	0.6	0.0002

^a

Extrapolated K_m and k_cat values.

^b

Turnover number measured with 1,000 mM galactose.

^c

The relative standard error (n = 3) for all reported K_m and k_cat values was <10%.