Table 3.

Kinetic parameters of LrPduO variants using the Co⁺ assay. The substrate cob(I)alamin was generated chemically using Ti(III)citrate

Enzyme	ATP			Cob(I)alamin
	Km (μM)	kcat (s−1)	kcat/Km (M−1 s−1)	Km (μM)	kcat (s−1)	kcat/Km (M−1 s−1)
wild type	2.2 ± 0.1	(2.6 ± 0.1) × 10−2	(1.2 ± 0.1) × 104	0.13 ± 0.01	(2.4 ± 0.1) × 10−2	(1.8 ± 0.2) × 105
F112A	34.6 ± 8.8	(5.6 ± 0.0) × 10−3	(1.7 ± 0.4) × 102	1.9 ± 0.5	(6.6 ± 0.5) × 10−3	(3.6 ± 1.0) × 103
F112H	2.6 ± 0.0	(3.8 ± 0.1) × 10−4	(1.4 ± 0.1) × 102	2.8 ± 0.4	(4.2 ± 0.1) × 10−4	(1.5 ± 0.2) × 102
F112Y	1.2 ± 0.1	(1.6 ± 0.0) × 10−3	(1.4 ± 0.1) × 103	0.55 ± 0.05	(1.7 ± 0.0) × 10−3	(3.1 ± 0.3) × 103
F112W	2.0 ± 0.6	(1.8 ± 0.2) × 10−3	(9.8 ± 3.4) × 102	0.77 ± 0.12	(2.0 ± 0.2) × 10−3	(2.6 ± 0.5) × 103
F163A	15.9 ± 6.8	(1.5 ± 0.1) × 10−2	(1.8 ± 0.4) × 103	0.19 ± 0.03	(1.5 ± 0.3) × 10−2	(7.9 ± 1.9) × 104
F187A	1.2 ± 0.4	(2.1 ± 0.4) × 10−2	(1.7 ± 0.6) × 104	0.11 ± 0.01	(1.8 ± 0.1) × 10−2	(1.6 ± 0.2) × 105
ΔS183	3.1 ± 0.2	(2.3 ± 0.6) × 10−2	(7.5 ± 2.2) × 103	0.07 ± 0.06a	(2.0 ± 0.2) × 10−2	3.95 ± × 105

^asignificant error due to absorbance near detection limit