Fig. 1.

Integration of photosynthetic light reactions and C metabolism. The light reactions include the reaction center/electron transport components PSI and PSII (green), cytochrome b₆f (b₆f) (orange), and ATP synthase (blue), with CBBC (cycle, Upper Right) and starch biosynthesis (pathway, Upper Left) using the products of these reactions. Metabolites: G3P, glyceraldehyde 3-phosphate; F6P, fructose 6-phosphate; G6P, glucose 6-phosphate; G1P, glucose 1-phosphate. C metabolism-related enzymes are highlighted in gold filled rectangles (Rubisco, ribulose bisphosphate carboxylase oxygenase; PGM, phosphoglucomutase; SS, starch synthase). Other enzymes/electron transfer components are PC, plastocyanin (gray-filled circle, involved in transferring electrons from cytochrome b₆f to PSI); PTOX and FLV (blue-filled ovals; involved in reducing O₂); NDA2, NADPH oxidoreductase (gray-filled rectangle; moves electrons into the PQ pool); FDX, ferredoxin; TRX, thioredoxin; FNR, flavin:NADPH reductase (gray-filled circles; moves electrons out of the electron transport chain).