Enhancing plant photosynthetic performances by boosting plant carbonic anhydrase activity

Sara Beltrami ¹, Francesca Alderotti ², Damiano Tanini ³, Cecilia Brunetti ⁴, Francesco Ferrini ¹, Ermes Lo Piccolo ¹, Antonella Gori ¹

University of Florence, Department of Agriculture, Food, Environment and Forestry (DAGRI) ¹, National Research Council of Italy (CNR), Florence ², University of Florence, Department of Chemistry ³, National Research Council of Italy (CNR), Institute for Sustainable Plant Protection ⁴

Photosynthesis, which provides the basis of plant productivity, holds important significance across a spectrum of agro-industrial applications. Despite genetic manipulation, alternative opportunities exist to enhance photosynthetic performances. One promising approach involves enhancing the activity of carbonic anhydrases (CAs), metalloenzymes that catalyze the reversible interconversion of carbon dioxide (CO2) and bicarbonate (HCO3−). Besides catalyzing this interconversion, CAs play a crucial role in facilitating the movement of both CO2 and HCO3− across membranes. Activation studies on animal carbonic anhydrases (CAs) highlighted that several organic compounds can modulate their activity, raising the hypothesis that treating plants with different CA-activators could increase plant photosynthetic activity. Our results showed that foliar treatments with a newly synthesized selenium-based amine (Se-AMA) improved the photosynthetic efficiency of Arabidopsis thaliana without negatively affecting plant health. Se-AMA significantly increased net photosynthesis (A) and stomatal conductance (gs) in treated plants, with the most pronounced effects observed at a concentration of 100 µM after 10 days of treatment. Higher concentrations of Se-AMA proved even more effective, boosting A and gs already after 3 days of application. A single treatment with Se-AMA at 300 µM performed in the morning enhanced plant photosynthetic performance throughout the day, confirming that the positive effect of Se-AMA on A and gs can last several hours from its application. Additionally, Se-AMA was found to increase water content in treated plants, due to the elevated transpiration rate imposed by high values of gs. These effects may be associated with the possible role of Se-AMA in regulating the activity of specific CA isoforms, which may operate together with aquaporins to facilitate water transport and stomatal regulation, thereby supporting improved physiological processes related to water absorption and resource management. Besides very preliminary, our findings highlight the potential of Se-AMA to improve plant photosynthetic performances under conditions of non-limiting water availability. Future research will focus on exploring the mechanism by examining CA activity and aquaporin expression, even under water stress conditions.

Main author career stage: Postdoc / Fellow

Contribution type: Talk

First choice session: 6. Plants, Fungi and Society

Second choice session: 4. Structure, physiology, and development