Cyanobacterial myxoxanthophylls: biotechnological interventions and biological implications

Abstract

Cyanobacteria safeguard their photosynthetic machinery from oxidative damage caused by adverse environmental factors such as high-intensity light. Together with many photoprotective compounds, they contain myxoxanthophylls, a rare group of glycosidic carotenoids containing a high number of conjugated double bonds. These carotenoids have been shown to: have strong photoprotective effects, contribute to the integrity of the thylakoid membrane, and upregulate in cyanobacteria under a variety of stress conditions. However, their metabolic potential has not been fully utilized in the stress biology of cyanobacteria and the pharmaceutical industry due to a lack of mechanistic understanding and their insufficient biosynthesis. This review summarizes current knowledge on: biological function, genetic regulation, biotechnological production, and pharmaceutical potential of myxoxanthophyll, with a focus on strain engineering and parameter optimization strategies for increasing their cellular content. The summarized knowledge can be utilized in cyanobacterial metabolic engineering to improve the stress tolerance of useful strains and enhance the commercial-scale synthesis of myxoxanthophyll for pharmaceutical uses.

Keywords:

• Carotenoids
• cyanobacteria
• myxoxanthophyll
• metabolic engineering
• sigma factor

Acknowledgements

PS acknowledges the BTISNet-Sub-Distributed Information Centre, funded by DBT, Govt. of India at the School of Biotechnology, Banaras Hindu University, Varanasi, India. HC and ST acknowledge the infrastructural facilities provided under the project funded by ICAR-NBAIM, India.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Science & Engineering Research Board (SERB) Department of Science and Technology, Government of India (Grant No. CRG/2021/001206), ‘Faculty Incentive Grant’ by Institute of Eminence (IoE) Scheme by BHU, Varanasi (Letter No. R/ Dev/D/IoE/Seed & Incentive/2022-23/50024) and Ramanujan Fellowship (file no. RJF/2020/000043) by Science and Engineering Research Board (SERB), Department of Science and Technology (DST), New Delhi, India.