TABLE 1.

Comparison of kinetic parameters for the cyanide detoxification activity of the rhodanese variants

Rhodanese	Km(TS)	Km(KCN)	Vmaxa	kcat	kcat/Km(TS)	kcat/Km(KCN)
	mm	mm	μmol min−1 mg−1	s−1	m−1 s−1	m−1 s−1
Wild-type	39.5 ± 2.5	29 ± 4	1636 ± 44	910	23 × 103	31 × 103
E102D	88.7 ± 11.6	7.0 ± 0.5	6762 ± 59	3736	42 × 103	534 × 103
P285A	24 ± 3	51 ± 3	4412 ± 81	2437	101 × 103	48 × 103

^a V_max was estimated from graphs in which the concentration of cyanide was varied. The V_max estimates obtained from graphs in which the concentration of thiosulfate was varied are: wild-type (1846 ± 49 μmol min⁻¹ mg⁻¹, k_cat = 1020 s⁻¹), E102D (7287 ± 59 μmol min⁻¹ mg⁻¹, k_cat = 4026 s⁻¹), and P285A (4204 ± 92 μmol min⁻¹ mg⁻¹, k_cat = 2322 s⁻¹).