Table 1.

Kinetic constants for wt and mutants of the expressed catalytic domain of MIHCK

Protein	kcat, s−1	Km(peptide), mM	Km(ATP), mM	kcat/Km(peptide), s−1/mM	kcat/Km(ATP), s−1/mM
wt	71	0.15	0.16	473	444
S627A	10	0.81	0.57	12	18
S627D	8	1.10	0.49	7	16
S627E	37	1.21	0.80	31	46
T631A	18	1.56	1.10	12	16
T631D	2	0.86	0.56	2	4
T631E	0.36	2.40	2.80	0.2	0.1
T632A	105	0.20	0.30	525	350
T632D	23	0.64	0.68	36	34
T632E	23	0.25	0.69	92	33

Data were obtained as explained in Materials and Methods and illustrated in Fig. 2 for the T632A mutant.