succ_dehyd_cytB: succinate dehydrogenase, cytochrome b556 subunit.

Fumarate reductase iron-sulfur subunit; Two distinct, membrane-bound, FAD-containing enzymes are responsible for the catalysis of fumarate and succinate interconversion; the fumarate reductase is used in anaerobic growth, and the succinate dehydrogenase is used in aerobic growth; Belongs to the succinate dehydrogenase/fumarate reductase iron-sulfur protein family.

Fumarate reductase subunit C; Seems to be involved in the anchoring of the catalytic components of the fumarate reductase complex to the cytoplasmic membrane.

Fumarate reductase subunit D; Seems to be involved in the anchoring of the catalytic components of the fumarate reductase complex to the cytoplasmic membrane.

Succinate dehydrogenase, hydrophobic membrane anchor protein; Membrane-anchoring subunit of succinate dehydrogenase (SDH).

Fumarate hydratase, class II; Involved in the TCA cycle. Catalyzes the stereospecific interconversion of fumarate to L-malate; Belongs to the class-II fumarase/aspartase family. Fumarase subfamily.

succinyl-CoA ligase [ADP-forming] subunit beta; Succinyl-CoA synthetase functions in the citric acid cycle (TCA), coupling the hydrolysis of succinyl-CoA to the synthesis of either ATP or GTP and thus represents the only step of substrate-level phosphorylation in the TCA. The beta subunit provides nucleotide specificity of the enzyme and binds the substrate succinate, while the binding sites for coenzyme A and phosphate are found in the alpha subunit.

NADH-quinone oxidoreductase subunit C/D; 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 C-terminal section; belongs to the complex I 49 kDa subunit family.

succinyl-CoA ligase [ADP-forming] subunit alpha; Succinyl-CoA synthetase functions in the citric acid cycle (TCA), coupling the hydrolysis of succinyl-CoA to the synthesis of either ATP or GTP and thus represents the only step of substrate-level phosphorylation in the TCA. The alpha subunit of the enzyme binds the substrates coenzyme A and phosphate, while succinate binding and nucleotide specificity is provided by the beta subunit.