NADH-ubiquinone oxidoreductase subunit CD NuoCD; NDH-1 shuttles electrons from NADH, via FMN and iron-sulfur (Fe-S) centers, to quinones in the respiratory chain. The immediate electron acceptor for the enzyme in this species is believed to be ubiquinone. Couples the redox reaction to proton translocation (for every two electrons transferred, four hydrogen ions are translocated across the cytoplasmic membrane), and thus conserves the redox energy in a proton gradient; In the N-terminal section; belongs to the complex I 30 kDa subunit family.

Periplasmic nitrate reductase cytochrome c subunit NapB; Electron transfer subunit of the periplasmic nitrate reductase complex NapAB. Receives electrons from the membrane-anchored tetraheme c-type CymA protein and transfers these to NapA subunit, thus allowing electron flow between membrane and periplasm. Not essential for nitrate reduction but confers advantage to the organism when grown on nitrate and thereby a fitness gain in utilizing nitrate. Belongs to the NapB family.

Periplasmic nitrate reductase chaperone NapD; Chaperone for NapA, the catalytic subunit of the periplasmic nitrate reductase. It binds directly and specifically to the twin- arginine signal peptide of NapA, preventing premature interaction with the Tat translocase and premature export.

Periplasmic nitrate reductase molybdopterin-binding subunit NapA; Catalytic subunit of the periplasmic nitrate reductase complex NapAB. Receives electrons from NapB and catalyzes the reduction of nitrate to nitrite.

Ubiquinol-cytochrome c reductase FeS subunit PetA; Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is a respiratory chain that generates an electrochemical potential coupled to ATP synthesis.

Aa3-type cytochrome c oxidase subunit II CoxB; Subunits I and II form the functional core of the enzyme complex. Electrons originating in cytochrome c are transferred via heme a and Cu(A) to the binuclear center formed by heme a3 and Cu(B).

NADH-ubiquinone oxidoreductase subunit G NuoG; NDH-1 shuttles electrons from NADH, via FMN and iron-sulfur (Fe-S) centers, to quinones in the respiratory chain. The immediate electron acceptor for the enzyme in this species is believed to be ubiquinone. Couples the redox reaction to proton translocation (for every two electrons transferred, four hydrogen ions are translocated across the cytoplasmic membrane), and thus conserves the redox energy in a proton gradient (By similarity).

NADH-ubiquinone oxidoreductase subunit N NuoN; NDH-1 shuttles electrons from NADH, via FMN and iron-sulfur (Fe-S) centers, to quinones in the respiratory chain. The immediate electron acceptor for the enzyme in this species is believed to be ubiquinone. Couples the redox reaction to proton translocation (for every two electrons transferred, four hydrogen ions are translocated across the cytoplasmic membrane), and thus conserves the redox energy in a proton gradient; Belongs to the complex I subunit 2 family.

NADH-ubiquinone oxidoreductase subunit B NuoB; NDH-1 shuttles electrons from NADH, via FMN and iron-sulfur (Fe-S) centers, to quinones in the respiratory chain. The immediate electron acceptor for the enzyme in this species is believed to be ubiquinone. Couples the redox reaction to proton translocation (for every two electrons transferred, four hydrogen ions are translocated across the cytoplasmic membrane), and thus conserves the redox energy in a proton gradient.