Temperature acclimation of photosynthesis: Mechanisms involved in the changes in temperature dependence of photosynthetic rate

Growth temperature alters temperature dependence of the photosynthetic rate (temperature acclimation). In many species, the optimal temperature that maximizes the photosynthetic rate increases with increasing growth temperature. In this minireview, mechanisms involved in changes in the photosynthesis- temperature curve are discussed. Based on the biochemical model of photosynthesis, change in the photosynthesis-temperature curve is attributable to four factors: intercellular CO₂ concentration, activation energy of the maximum rate of RuBP (ribulose-1,5-bisphosphate) carboxylation (V _{c max}), activation energy of the rate of RuBP regeneration (J _max), and the ratio of J_max to V_{c max}. In the survey, every species increased the activation energy of V_{c max} with increasing growth temperature. Other factors changed with growth temperature, but their responses were different among species. Among these factors, activation energy of V_{c max} may be the most important for the shift of optimal temperature of photosynthesis at ambient CO₂ concentrations. Physiological and biochemical causes for the change in these parameters are discussed.