Table 7.

Activities of the wild-type and mutant RePC for the MgADP phosphorylation reaction using either carbamoyl phosphate or acetyl phosphate in the presence and absence of biotin^a.

					(+) 10 mM free biotin
	kcat (min−1)b	Km (mM)	kcat/Km (min−1mM−1)	% wild- type kcat/Km	kcat (min−1)	Km (mM)	kcat/Km (min−1 mM−1)	% wild- type kcat/Km
Carbamoyl phosphate c
wild-type	2.4 ± 0.1	2.6 ± 0.5	0.93 ± 0.02	(100)	4.1 ± 0.3	3.3 ± 0.5	1.2 ± 0.1	(100)
K1119Q	0.014 ± 0.001	0.88 ± 0.07	0.16 ± 0.01	17	2.1 ± 0.1	3.9 ± 0.6	0.54 ± 0.06	45
T882A	24 ± 1	3.4 ± 0.5	7.0 ± 0.6	750	32.1 ± 0.8	2.9 ± 0.2	11 ± 1	920
Acetyl phosphate d
wild-type	0.58 ± 0.01	0.34 ± 0.02	1.70 ± 0.05	(100)	0.29 ± 0.002	0.14 ± 0.04	2.1 ± 0.2	(100)
K1119Q	0.47 ± 0.01	0.29 ± 0.01	1.62 ± 0.05	95	0.44 ± 0.01	0.37 ± 0.03	1.19 ± 0.02	57
T882A	0.30 ± 0.01	0.22 ± 0.01	1.36 ± 0.01	80	0.12 ± 0.01	0.14 ± 0.01	0.85 ± 0.03	40

^aReaction conditions: 50 mM Bis-Tris, 25 mM Tricine, 25 mM glycine (pH 7.5), 25° C, 7.5 mM MgCl , 3.5 mM MgADP, 0.25 mM acetyl-CoA.

^bData fitted to eqn (1).

^cCarbamoyl phosphate varied phosphoryl donor (1-20 mM).

^dAcetyl phosphate varied phosphoryl donor (0.1-20 mM).