TABLE 3.

Metal equivalents^a and corresponding activity of MolA with molinate

Enzyme treatmentb	No. of metal equivalents				Activity with molinate
	Cobalt	Copper	Iron	Zinc	Km (μM) ± SE	kcat (s−1) ± SE	kcat/Km (s−1 M−1) ratio
Iron	0.00	0.03	1.15	0.02	46 ± 18	1.1 × 10−3 ± 0.2 × 10−4	23.3
Copper	0.00	1.23	0.01	0.01	56 ± 4.6	1.7 × 10−3 ± 2.0 × 10−4	32.2
Cobalt	0.37	0.11	0.01	0.02	14 ± 0.7	33 × 10−3 ± 4.8 × 10−4	2,380
Zinc	0.00	0.04	0.01	0.97	55 ± 2.5	29 × 10−3 ± 2.5 × 10−4	520

^aMetal concentration relative to protein concentration as determined by ICP-OES. All proteins were desalted into metal-free buffer before analysis.

^bMolA was expressed in medium supplemented with the respective metals at 100 μM.