Ebenhöh 2014, Philos Trans.

The Ebenhöh 2014 model is a kinetic model of the photosynthetic electron transport chain (PETC), built to study how a photosynthetic organism acclimates to changing light on short timescales. It comprises seven coupled ordinary differential equations and represents the main components of the PETC — photosystem II (PSII), the plastoquinone pool, the cytochrome b6f complex, plastocyanin, photosystem I (PSI), ferredoxin, ferredoxin-NADP+ reductase and the ATP synthase — together with both linear and cyclic electron flow. PSII is described under a quasi-steady-state assumption using a four-state reaction-center model. In addition, the model captures the relocation of light-harvesting complexes between PSII and PSI (state transitions), thereby changing the antenna cross sections of the two photosystems.

Because the model was developed to describe short-term acclimation of the PETC to different light regimes, it was validated against PAM fluorescence data from Chlamydomonas reinhardtii, showing both light-induced and anoxia-induced state transitions. The light-induced state transition reported in the publication is reproduced exactly by this implementation; the anoxia-induced state transition and figure 3, however, show some discrepancies from the original publication while still agreeing with the overall dynamics. Beyond serving as a base model for short-term PETC acclimation, it provided the foundation for Matuszynska 2016 and Matuszynska 2019. For that reason, it is included in GreenSloth as a starting point for understanding how the light reactions of photosynthesis are modeled.

Model definition