Increased fluxes through the physiological pathways used for H
production in Chlamydomonas under dark condition. Acetate is assimilated (red arrows) and starch is produced through gluconeogenic conversion. Green arrows highlight increased fluxes through acetate metabolism, starch synthesis/degradation and the physiological pathways for H2 production in Chlamydomonas. The blue arrows are the increased fluxes through enzymes involved in H2 synthesis. Numbers represent the main enzymatic and transport reactions: (1) acetate assimilation; (2,4) acetate transporter; (3,5) acetyl-Coa synthetase; (6,7) succinate transporter; (8) phosphoenolpyruvate carboxykinase; (9) phosphoglucomutase (10) 1,4-alpha-glucan branching enzyme; (11) glyceraldehyde 3-phosphate dehydrogenase; (12) pyruvate kinase; (13) pyruvate ferredoxin oxidoreductase (PFR1); (14) ferredoxin hydrogenase. GLU: glucose; PEP: Phosphoenolpyruvate; G6P: glucose 6-phosphate; SUCC: Succinatate; MAL: malate; CIT: citrate; OAA: oxaloacetate; FDX red: reduced ferredoxin; FDX ox: oxidized ferredoxin.