TABLE 6.

Thermodynamic parameters for nucleotide complexes of CBS-PPases obtained by isothermal calorimetry

Enzyme/nucleotide	KN	n	ΔH	−TΔS
	μm		kcal/mol	kcal/mol
dhPPase
AMP	0.8 ± 0.3	0.79 ± 0.05	−5.6 ± 0.5	−2.7 ± 0.6
ADP	1.0 ± 0.2	0.85 ± 0.04	−5.9 ± 0.4	−2.4 ± 0.5
ATP	1.2 ± 0.1	0.80 ± 0.02	−5.8 ± 0.2	−2.4 ± 0.2
Ap3A	0.12 ± 0.05	0.97 ± 0.02	−5.3 ± 0.2	−4.0 ± 0.3
Ap4A		0.41 ± 0.01	−10.4 ± 0.3
Ap5A		0.41 ± 0.01	−10.3 ± 0.3
cnPPase
AMP	0.9 ± 0.4	0.80 ± 0.08	−5.9 ± 0.9	−2.4 ± 1.0
ADP	5 ± 1	0.91 ± 0.08	−3.0 ± 0.6	−4.1 ± 1.0
ATP	0.6 ± 0.2	0.89 ± 0.07	−5.8 ± 0.7	−2.8 ± 1.1
Ap3A		0.94 ± 0.01	−6.1 ± 0.1
Ap4A		0.44 ± 0.01	−9.7 ± 0.3
cpPPase
AMP	0.97 ± 0.03	0.87 ± 0.06	−6.0 ± 0.6	−2.3 ± 0.7
ADP	2.6 ± 0.5	0.94 ± 0.09	−6.0 ± 0.8	−1.6 ± 0.3
ATP	0.23 ± 0.06	1.00 ± 0.03	−5.6 ± 0.3	−3.6 ± 0.9
Ap3A	0.7 ± 0.3	0.97 ± 0.11	−5.7 ± 1.1	−2.7 ± 1.2
Ap4A		0.42 ± 0.01	−10.4 ± 0.3
elPPase
AMP			≤0.1
ADP	9 ± 4	0.95 ± 0.1	−4.5 ± 1.6	−2.4 ± 2.0
ATP	5 ± 1	1.0 ± 0.4	−8 ± 4	−0.5 ± 0.3
Ap3A			≤0.1
Ap4A			≤0.1