. Author manuscript; available in PMC: 2014 Jun 25.

Published in final edited form as: Biochemistry. 2013 Jun 13;52(25):4343–4353. doi: 10.1021/bi400354n

Table 4.

Prosthetic group content and substrate-binding affinities of wild type nitrate reductase and its variants.

Enzyme	Sulfide^a	Iron^a	Molybdenum^a	K_d Nitrate (μM)	K_d Ferredoxin (μM)
Wild Type	3.5±0.2	3.5±0.77	0.80±0.34	1.0±0.3	7.8±2.1
K58Q	2.7±0.18	0.7±0.18	0.80±0.15	8.0±2.3	85.0±9.6
K58R	2.8±0.22	1.1±0.31	0.19±0.08	15.5±5.0	7.5±2.6
R70Q	2.8±0.16	2.1±0.57	0.67±0.27	5.5±2.2	3.0±1.0
R70K	3.0±0.29	1.6±0.12	0.36±0.08	6.0±1.0	3.2±1.7
K130Q	3.1±0.24	3.6±0.15	0.39±0.02	19.0±6.8	12.6±2.4
K130R	3.4±0.28	3.0±0.075	0.46±0.02	13.4±3.0	8.0±0.2
R146Q	3.2±0.31	3.8±0.44	1.07±0.11	1.5±0.4	2.6±0.3

mol/mol of enzyme