Fermentative Succinate Production: An Emerging Technology to Replace the Traditional Petrochemical Processes
Figure 2
Anaerobic (a) and aerobic (b) metabolic pathways for the biosynthesis of succinate. Unidirectional arrows indicate that the reactions are irreversible while two-directional arrows indicate that the reactions are reversible. Enzymes whose genes are deleted are indicated by “X” across arrows. The abbreviations for the enzymes catalyzing these reactions are ack, acetate kinase; acn, aconitase; adh, alcohol/acetaldehyde dehydrogenase; cs, citrate synthase; frd, fumarate reductase; fum, fumarase; icd, isocitrate dehydrogenase; icl, isocitrate lyase; kgd, -ketoglutarate dehydrogenase; ldh, lactate dehydrogenase; mae, malic enzyme; mdh, malate dehydrogenase; ms, malate synthase; pck, PEP carboxykinase; pfl, pyruvate-formate lyase; pox, pyruvate oxidase; ppc, PEP carboxylase; pta, phosphotransacetylase; pyc, pyruvate carboxylase; pyk, pyruvate kinase; scs, succinyl-CoA synthetase; and sdh, succinate dehydrogenase.
