Advances in Genetic Engineering in Improving Photosynthesis and Microalgal Productivity

Abstract

Even though sunlight energy far outweighs the energy required by human activities, its utilization is a key goal in the field of renewable energies. Microalgae have emerged as a promising new and sustainable feedstock for meeting rising food and feed demand. Because traditional methods of microalgal improvement are likely to have reached their limits, genetic engineering is expected to allow for further increases in the photosynthesis and productivity of microalgae. Understanding the mechanisms that control photosynthesis will enable researchers to identify targets for genetic engineering and, in the end, increase biomass yield, offsetting the costs of cultivation systems and downstream biomass processing. This review describes the molecular events that happen during photosynthesis and microalgal productivity through genetic engineering and discusses future strategies and the limitations of genetic engineering in microalgal productivity. We highlight the major achievements in manipulating the fundamental mechanisms of microalgal photosynthesis and biomass production, as well as promising approaches for making significant contributions to upcoming microalgal-based biotechnology.

Identification and Functional Analysis of Two Novel Genes—Geranylgeranyl Pyrophosphate Synthase Gene (AlGGPPS) and Isopentenyl Pyrophosphate Isomerase Gene (AlIDI)—from Aurantiochytrium limacinum Significantly Enhance De Novo β-Carotene Biosynthesis in Escherichia coli

“…In this work, no transmembrane domain was predicted in AlIDI and AlGGPPS (Figure 1), which might help them to function efficiently in E. coli. Furthermore, the application of these two novel functional genes could be extended to other prokaryotes, such as Synechocystis, which is regarded as a potential cell factory for carotenoid synthesis [21,53,54].…”

Artificial Photosynthesis: Current Advancements and Future Prospects

“…These findings imply that increasing the expression of the specific PEPC enzyme has the potential to enhance photosynthesis, making it a promising avenue for future developments. The results of these studies have inspired several research projects aimed at enhancing CO2 capture for both environmental and economic purposes (Figure 19) [182]. Photosynthesis, in general, is an inefficient process, with over 75% of the radiation that reaches plants and algae being lost [183].…”

Harnessing genetic engineering to drive economic bioproduct production in algae

“…Despite the elevated operational costs associated with photobioreactors using artificial light, there are significant increases in biomass and intracellular metabolite productivity ( Ramanna et al, 2017 ). To further enhance photosynthetic efficiency and overall biomass productivity in microalgal cultures, strategies such as mutagenesis, genetic engineering, and DNA insertional mutagenesis are employed ( Vecchi et al, 2020 ; Kumar et al, 2021 ; Hu et al, 2023 ). Photosynthetic efficiency in microalgae is often hindered by photoinhibition, a response to excessive light exposure.…”

“…Photosynthetic efficiency in microalgae is often hindered by photoinhibition, a response to excessive light exposure. Algae with truncated antenna systems are beneficial in mitigating this issue, as they absorb less light per cell, reducing the problem of supersaturation in the photosynthetic efficiency ( Kumar et al, 2020 ; Kumar et al, 2021 ; Vecchi et al, 2020 ; Hu et al, 2023 ). Additionally, the process of non-photochemical quenching (NPQ) is a photoprotective mechanism that can be manipulated to increase biomass productivity in microalgae.…”