Table II.

Reduction potentials and relative apparent reaction rates of variant NiRs

Variant	Oxygen reduction (o-dianisidine)	Nitrite reduction (o-dianisidine)	Oxygen reduction (pseudoazurin)	Nitrite reduction (pseudoazurin)	E1/2 (mV)f
Wt	1a	1b	1c	1d	250
F312C	2.70 ± 0.04	0.54 ± 0.05	0.23 ± 0.02	0.22 ± 0.02	250
M94T	0.73 ± 0.03	0.92 ± 0.14	1.1 ± 0.1	0.59 ± 0.04	236
M62L	1.30 ± 0.02	3.1 ± 0.1	0.81 ± 0.04	2.1 ± 0.0	272
M150L	3.4 ± 0.7	8.5 ± 0.6	0.38 ± 0.03	0.30 ± 0.01	275
N96S	1.3 ± 0.1	5.9 ± 0.1	0.15 ± 0.01	0.41 ± 0.01	261
F312C/M94T	2.7 ± 0.5	0.64 ± 0.06	0.20 ± 0.03	0.62 ± 0.07	215
F312C/M150L	5.5 ± 0.3	6.8 ± 0.3	0.12 ± 0.01	0.22 ± 0.01	265
D98N	0.90 ± 0.25	1.3 ± 0.1	0.05 ± 0.03	0.01 ± 0.00	e

^aWt apparent rate of oxygen reduction using o-dianisidine as the electron donor: 0.0042 ± 0.0003 s⁻¹.

^bWt apparent rate of nitrite reduction using o-dianisidine as electron donor: 0.15 ± 0.01 s⁻¹.

^cWt apparent rate of oxygen reduction using pseudoazurin as the electron donor: 14.0 ± 0.3 s⁻¹.

^dWt apparent rate of nitrite reduction using pseudoazurin as the electron donor: 401 ± 23 s⁻¹.

^eReduction potential not measured in this study but presumed to be similar to wt.

^fReducton potentials are measured with an uncertainty of ±1 mV.