Aconitate hydratase 1; Catalyzes the reversible isomerization of citrate to isocitrate via cis-aconitate. The apo form of AcnA functions as a RNA- binding regulatory protein which plays a role as a maintenance or survival enzyme during nutritional or oxidative stress. During oxidative stress inactive AcnA apo-enzyme without iron sulfur clusters binds the acnA mRNA 3' UTRs (untranslated regions), stabilizes acnA mRNA and increases AcnA synthesis, thus mediating a post- transcriptional positive autoregulatory switch. AcnA also enhances the stability of the sodA transcript.

Isocitrate dehydrogenase, specific for NADP+; Protein involved in tricarboxylic acid cycle and anaerobic respiration; Belongs to the isocitrate and isopropylmalate dehydrogenases family.

2-methylcitrate dehydratase; Involved in the catabolism of short chain fatty acids (SCFA) via the tricarboxylic acid (TCA)(acetyl degradation route) and via the 2-methylcitrate cycle I (propionate degradation route). Catalyzes the dehydration of 2-methylcitrate (2-MC) to yield the cis isomer of 2- methyl-aconitate. It is also able to catalyze the dehydration of citrate and the hydration of cis-aconitate at a lower rate. Due to its broad substrate specificity, it seems to be responsible for the residual aconitase activity of the acnAB-null mutant. Belongs to the PrpD family.

succinyl-CoA synthetase, beta subunit; 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. Can use either ATP or GTP, but prefers ATP. It can also function in the other direction for anabolic purposes, and this may be particularly impor [...]

Isocitrate lyase; Involved in the metabolic adaptation in response to environmental changes. Catalyzes the reversible formation of succinate and glyoxylate from isocitrate, a key step of the glyoxylate cycle, which operates as an anaplerotic route for replenishing the tricarboxylic acid cycle during growth on fatty acid substrates.

2-oxoglutarate decarboxylase, thiamine triphosphate-binding; E1 component of the 2-oxoglutarate dehydrogenase (OGDH) complex which catalyzes the decarboxylation of 2-oxoglutarate, the first step in the conversion of 2-oxoglutarate to succinyl-CoA and CO(2).

Dihydrolipoyltranssuccinase; E2 component of the 2-oxoglutarate dehydrogenase (OGDH) complex which catalyzes the second step in the conversion of 2- oxoglutarate to succinyl-CoA and CO(2).

Fumarate hydratase (fumarase A), aerobic Class I; Catalyzes the reversible hydration of fumarate to (S)-malate. Functions as an aerobic enzyme in the direction of malate formation as part of the citric acid cycle. Accounts for about 80% of the fumarase activity when the bacteria grow aerobically. To a lesser extent, also displays D-tartrate dehydratase activity in vitro, but is not able to convert (R)-malate, L-tartrate or meso-tartrate. Can also catalyze the isomerization of enol- to keto-oxaloacetate.

Malate dehydrogenase, NAD(P)-binding; Catalyzes the reversible oxidation of malate to oxaloacetate.