Table 1.

Kinetic parameters determined from steady-state kinetic experiments

Results presented are the average values from multiple experiments.

Reaction	kcat	kcat/Km	Km
	min−1	min−1 μm−1	μm
11-Deoxycorticosterone → corticosterone	33 ± 1	13 ± 1	2.7 ± 0.3
Corticosterone → 18-OH corticosteronea	14.9 ± 0.4	0.49 ± 0.2	31 ± 1
Corticosterone → aldosteronea	2.84 ± 0.09	0.103 ± 0.007	28 ± 2
18-OH corticosterone → aldosteroneb		6.7 × 10−5 ± 2 × 10−6

^a The production of 18-OH corticosterone from corticosterone could not be isolated from the production of aldosterone; therefore, the presented values are not true steady-state parameters because the data reports on both reactions simultaneously.

^b Saturation of the hyperbolic curve was not achieved due to the limit of substrate solubility. Only k_cat/K_m was determined; see under “Experimental procedures” for details.