Chitosan-Modified Polyethyleneimine Nanoparticles for Enhancing the Carboxylation Reaction and Plants’ CO₂Uptake

Abstract

Increasing plants' photosynthetic efficiency is a major challenge that must be addressed in order to cover the food demands of the growing population in the changing climate. Photosynthesis is greatly limited at the initial carboxylation reaction, where CO 2 is converted to the organic acid 3-PGA, catalyzed by the RuBisCO enzyme. RuBisCO has poor affinity for CO 2 , but also the CO 2 concentration at the RuBisCO site is limited by the diffusion of atmospheric CO 2 through the various leaf compartments to the reaction site. Beyond genetic engineering, nanotechnology can offer a materials-based approach for enhancing photosynthesis, and yet, it has mostly been explored for the light-dependent reactions. In this work, we developed polyethyleneimine-based nanoparticles for enhancing the carboxylation reaction. We demonstrate that the nanoparticles can capture CO 2 in the form of bicarbonate and increase the CO 2 that reacts with the RuBisCO enzyme, enhancing the 3-PGA production in in vitro assays by 20%. The nanoparticles can be introduced to the plant via leaf infiltration and, because of the functionalization with chitosan oligomers, they do not induce any toxic effect to the plant. In the leaves, the nanoparticles localize in the apoplastic space but also spontaneously reach the chloroplasts where photosynthetic activity takes place. Their CO 2 loading-dependent fluorescence verifies that, in vivo, they maintain their ability to capture CO 2 and can be therefore reloaded with atmospheric CO 2 while in planta. Our results contribute to the development of a nanomaterials-based CO 2 -concentrating mechanism in plants that can potentially increase photosynthetic efficiency and overall plants' CO 2 storage.

Advancement in Carbon Nanoparticle Synthesis and Their Application: A Comprehensive Review

“…It is a conical shape carbon nanostructure [42][43][44]. CNHs provide alternative of CNTs in wide range of applications such as energy conversion, drug delivery, gas storage and supercapacitors etc.in contrast to CNTs they differ in following ways such as absence of metallic catalyst in their synthesis and their mass production at room temperature [21,63,64]. CNHs can be synthesized by sufficient injection of energy to vaporize and differ from synthesis of CNTs.…”

Response of Photosynthesis in Wheat (Triticum aestivum L.) Cultivars to Moderate Heat Stress at Meiosis and Anthesis Stages

“…Some researchers reported that the concentration of CO 2 between plant leaf cells increased while promoting a significant increase in carboxylation efficiency (CE) [36,37]. The increase in carboxylation reaction efficiency showed that the storage of photosynthetic substances was accelerated, promoting reproductive growth, promoting photosynthesis in wheat plants, improving the transport of photosynthetic substances in the body, and promoting the synthesis and transport of organic compounds [38,39].…”

Biohybrid Energy Storage Circuits Based on Electronically Functionalized Plant Roots

“…Tailormade nanomaterials that were incorporated directly in plants apparatus enabled the development of environmental sensors. , The plant was acting as the sampler and concentrator of analytes while the nanomaterials produced a readable output. Functional nanomaterials can also enhance plant processes for example photosynthesis and CO 2 uptake or even give new capabilities to plants such as light emission. , Plants, being natural energy converters that transform sunlight to chemical energy, have also been the focus of biohybrid energy devices. Biofunctionalized electrodes integrated into the plant tissue can convert sugars and oxygen produced by photosynthesis into electricity. , Additionally, plants’ natural movements and leaves’ dielectric properties have been combined with artificial leaves for triboelectric generators that produce sufficient energy to power low consumption electronics. , Our group, on the other hand, demonstrated energy storage in plants via in vivo organization of conducting materials in their tissue that can act as charge storage electrodes in biohybrid supercapacitors …”