Nitrate reductase
From Proteopedia
Nitrate reductase (NR) catalyzes the reduction of NO3 to NO2 using NADPH . NR active site contains Mo atom. Four types of NR are known: one eukaryotic assimilatory NR and 3 bacterial NRs – cytoplasmic assimilatory (NAC), membrane-bound respiratory (NAR) and periplasmic dissimilatory (NAP). The cofactors of NR are Molybdopterin (MPT) in eukaryotic NR and bis-Molybdopterin guanine dinucleotide (MGD) in bacterial NR.
3D structures of nitrate reductase
Bacterial periplasmic dissimilatory NR
2nap, 2jim, 2jio, 2jip, 2v3v, 2v45 – DdNAP + MGD + Mo - Desulfovibrio desulfuricans
2jiq - DdNAP + NO3 + MGD + Mo
2jir - DdNAP + CN + MGD + Mo
1jni – NAP small subunit + heme – Haemophilus influenzae
1ogy - NAP + heme + MGD + Mo– Rhodobacter sphaeroides
2nya - EcNAP + MGD + Mo – Escherichia coli
3ml1, 3o5a - NAP catalytic subunit + NAPB + heme + MGD + Mo – Ralstonia eutropha
Bacterial respiratory NR
1q16 – EcNAR α+β+γ chains + heme + MGD + Mo
1r27 - EcNAR α+β chains + MGD + Mo
1siw – EcNAR α+β+γ chains + heme
1y4z, 3egw - EcNAR α+β (mutant) + γ chains + inhibitor + heme + MGD + Mo
1y5i, 1y5n - EcNAR α+β + γ (mutant) chains + inhibitor + heme + MGD + Mo
3ir5, 3ir7 - EcNAR α (mutant) +β + γ chains + inhibitor + heme + MGD + Mo
3ir6 - EcNAR α (mutant) +β + γ chains + inhibitor + heme + GDP
Eukaryotic assimilatory NR
2bih, 2bii – NR MoCo-binding domain + MPT – Pichia angusta
