Figure 2

Assumed metabolic model of an l -lysine-producing Corynebacterium glutamicum strain grown on glucose. Single (solid) and double (solid and dotted) lines with arrows correspond to the assumed irreversible reactions and to bi-directional (forward and reverse) reactions, respectively. The letter “θ” indicates fluxes assigned as free, and the letter “v” indicates dependent fluxes. The free and dependent fluxes are numbered continuously throughout the applied model. Amino acid biosynthetic pathways are shown schematically as the drain of precursors of the corresponding amino acid. Carbon sources are indicated with ovals. The following abbreviations are used for metabolites: 3PG – 3-phosphoglycerate; ACCOA – acetyl-CoA; ACETAL – acetaldehyde; ACETAL_EX – extracellular acetaldehyde; AKG – α-ketoglutarate; AKG_EX – extracellular α-ketoglutarate; CIT – lumped pool of citrate and isocitrate; CO2 - carbon dioxide; CO2_EX – extracellular carbon dioxide; DAP – diaminopimelate; DHAP – dihydroxyacetone phosphate; E4P – d-erythrose 4-phosphate; F16BP – fructose 1,6-bisphosphate; F6P – d-fructose 6-phosphate; G3P – glyceraldehyde 3-phosphate; GLC_EX – extracellular glucose; GLC6P – d-glucose 6-phosphate; GLY_EX – extracellular glycine; LAC - lactate; LAC_EX – extracellular lactate; LYS_ EX – extracellular lysine; MAL – malate; OAA – oxaloacetate; P5P – pentose-5-phosphates (lumped pool of d-ribulose 5-phosphate, d-ribose 5-phosphate, d-xylulose 5-phosphate); PEP – phosphoenolpyruvate; PYR – pyruvate; S7P – d-sedoheptulose 7-phosphate; SUC – succinate; TREM – trehalose constituent (d-glucose 6-phosphate and UDP-glucose); TRE_EX – extracellular trehalose. Amino acids are expressed using the standard three-letter code.