Fig. 1

Simplified scheme of central carbon metabolism in microalgae. Arrows represent potential carbon fluxes. Enzymes are in bold italics. Blue arrows represent reducing power (NADPH). Red arrows represent acetyl-CoA. Black boxes denote pathway names. Neutral lipid droplets found in microalgae consist mostly of triacylglycerols (TAGs), formed by combining FAs and glycerol. ACCase acetyl-CoA carboxylase; ACD acyl-CoA dehydrogenase; ACL ATP-citrate lyase; ACS acyl-CoA synthetase; AGPP ADP-glucose pyrophosphorylase; AMY amylase; CA carbonic anhydrase; DGAT diacylglycerol acyltransferase; DHAP dihydroxyacetone phosphate; F1,6P fructose 1,6-bisphosphate; F6P fructose 6-phosphate; FAT fatty acyl–acyl carrier protein (ACP) thioesterase; G1P glucose 1-phosphate; G6P glucose 6-phosphate; G6PDH G6P dehydrogenase; GAP glyceraldehyde 3-phosphate; GPAT glycerol-3-phosphate acyltransferase; MAL malate; MDH malate dehydrogenase; MME NADP-malic enzyme; OAA oxaloacetate; PDC pyruvate dehydrogenase complex; PEP phosphoenolpyruvate; PEPC PEP carboxylase; PK pyruvate kinase; Ru5P ribulose 5-phosphate; Ru1,5BP ribulose 1,5-bisphosphate; RuBisCO Ru1,5BP carboxylase/oxygenase; 3-PGA 3-phosphoglycerate; 6PGDH 6-phosphogluconate dehydrogenase