Figure 4.

Metabolic model for carbon assimilation in sugar beet roots under iron deficiency. Iron deficiency would cause an approximately 50-fold enhancement in carbon assimilation (C.A.) in the cytosol through the increase in PEPC activity, and approximately 5-fold increases in the Krebs cycle (K.C.) and respiratory chain (R.C.) in the mitochondria. Part of the malate and the citrate would be exported via xylem, thus providing respiratory substrates to the shoot. ACoA, Acetyl coenzyme A; CIT, citrate; FUM, fumarate; ISC, isocitrate; MAL, malate; OXA, oxalacetate; OXG, oxoglutarate; PYR, pyruvate; SCoA, succinyl coenzyme A; SUC, succinate.