Perin 2023 Proc Natl Acad Sci U S A
| Perin G, Bellan A, Michelberger T, Lyska D, Wakao S, Niyogi KK, Morosinotto T (2023) Modulation of xanthophyll cycle impacts biomass productivity in the marine microalga Nannochloropsis. Proc Natl Acad Sci U S A 120:e2214119120. https://doi.org/10.1073/pnas.2214119120 |
Perin G, Bellan A, Michelberger T, Lyska D, Wakao S, Niyogi KK, Morosinotto Tomas (2023) Proc Natl Acad Sci U S A
Abstract: Life on earth depends on photosynthetic primary producers that exploit sunlight to fix CO2 into biomass. Approximately half of global primary production is associated with microalgae living in aquatic environments. Microalgae also represent a promising source of biomass to complement crop cultivation, and they could contribute to the development of a more sustainable bioeconomy. Photosynthetic organisms evolved multiple mechanisms involved in the regulation of photosynthesis to respond to highly variable environmental conditions. While essential to avoid photodamage, regulation of photosynthesis results in dissipation of absorbed light energy, generating a complex trade-off between protection from stress and light-use efficiency. This work investigates the impact of the xanthophyll cycle, the light-induced reversible conversion of violaxanthin into zeaxanthin, on the protection from excess light and on biomass productivity in the marine microalgae of the genus Nannochloropsis. Zeaxanthin is shown to have an essential role in protection from excess light, contributing to the induction of nonphotochemical quenching and scavenging of reactive oxygen species. On the contrary, the overexpression of zeaxanthin epoxidase enables a faster reconversion of zeaxanthin to violaxanthin that is shown to be advantageous for biomass productivity in dense cultures in photobioreactors. These results demonstrate that zeaxanthin accumulation is critical to respond to strong illumination, but it may lead to unnecessary energy losses in light-limiting conditions and accelerating its reconversion to violaxanthin provides an advantage for biomass productivity in microalgae.
• Bioblast editor: Gnaiger E
Labels: MiParea: Respiration
Organism: Algae
Preparation: Intact cells
Regulation: Redox state Coupling state: ROUTINE
HRR: Oxygraph-2k, NextGen-O2k
PhotoBiology
