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. 2015 May 5;5:9777. doi: 10.1038/srep09777

Table 2. Kinetic parameters of purified LdhDs for NADH, NADPH, and pyruvate.

	Specific activity^a		Kinetic parameters
Enzyme	NADH	NADPH	NADH			NADPH
			K_m	k_cat	k_cat/K_m	K_m	k_cat	k_cat/K_m
	unit mg⁻¹		mM	s⁻¹	M⁻¹s⁻¹	mM	s⁻¹	M⁻¹s⁻¹
LdhD	361 ± 29.3	ND^b	2.3 ± 0.1^*	561 ± 41.9^*	(2.4 ± 0.2) × 105 *	ND^*	ND^*	ND^*
			1.1 ± 0.1^**	441 ± 31.8^**	(4.0 ± 0.3) × 10^{5 **}	ND^**	ND^**	ND^**
LdhD^A	156 ± 13.2	52.5 ± 4.8	5.9 ± 0.4^*	190 ± 15.2^*	(3.2 ± 0.3) × 10^{4 *}	6.4 ± 0.7^*	33.0 ± 2.2^*	(5.2 ± 0.6) × 10^{3 *}
			6.2 ± 0.5^**	270 ± 21.1^**	(4.3 ± 0.3) × 10^{4 **}	5.9 ± 0.5^**	3.1 ± 0.4^**	(1.9 ± 0.1) × 10^{3 **}
LdhD^R	268 ± 21.3	2.7 ± 0.2	3.0 ± 0.2^*	439 ± 34.8^*	(1.5 ± 0.1) × 10^{5 *}	20.0 ± 1.5^*	42.8 ± 4.4^*	(2.1 ± 0.2) × 10^{3 *}
			7.2 ± 0.6^**	1048 ± 89.9^**	(1.5 ± 0.2) × 10^{5 **}	210 ± 20.7^**	29.9 ± 3.0^**	(1.4 ± 0.1) × 10^{2 **}
LdhD^S	564 ± 55.8	0.3 ± 0.04	2.7 ± 0.2^*	500 ± 43.3^*	(1.9 ± 0.2) × 10^{5 *}	23.3 ± 2.1^*	8.6 ± 0.8^*	(3.7 ± 0.3) × 10^{2 *}
			2.4 ± 0.2^**	833 ± 65.6^**	(3.5 ± 0.2) × 10^{5 **}	82.5 ± 7.9^**	21.7 ± 2.0^**	(2.6 ± 0.2) × 10^{2 **}
LdhD^R2	318 ± 30.2	3.4 ± 0.4	3.0 ± 0.3^*	594 ± 50.8^*	(2.0 ± 0.2) × 10^{5 *}	29.0 ± 3.1^*	3.8 ± 0.3^*	(1.3 ± 0.1) × 10^{2 *}
			2.8 ± 0.3^**	916 ± 92.4^**	(3.3 ± 0.3) × 10^{5 **}	137 ± 9.3^**	28.8 ± 2.5^**	(2.1 ± 0.2) × 10^{2 **}
LdhDn^ARSdR	35.0 ± 1.8	150 ± 10.5	15.1 ± 0.8^*	129 ± 7.6^*	(8.5 ± 0.3) × 10^{3 *}	3.8 ± 0.2^*	163 ± 12.1^*	(4.4 ± 0.5) × 10^{4 *}
			10.3 ± 0.5^**	447 ± 35.6^**	(4.3 ± 0.2) × 10^{4 **}	2.25 ± 0.2^**	335 ± 27.4^**	(1.5 ± 0.1) × 10^{5 **}

^*Kinetic parameters for NADH or NADPH; ^**Kinetic parameters for pyruvate.

Values represent mean ± S.D. (n = 3).

^aUnder standard assay conditions as described under “Methods”.

^bND, the kinetic parameters were not determined because the enzymes showed no activity towards the substrate.