High-CO₂ tolerance in microalgae: possible mechanisms and implications for biotechnology and bioremediation

• Published in: Biotechnology letters Vol. 35; no. 11; pp. 1745 - 1752
• Main Authors: Solovchenko, Alexei, Khozin-Goldberg, Inna
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer-Verlag 01.11.2013; Springer Netherlands; Springer Nature B.V
• Subjects: acclimation; Acclimatization; adenosine triphosphate; Algae; Applied Microbiology; Biochemistry; Biodegradation, Environmental; Biomedical and Life Sciences; Bioremediation; Biotechnology; Biotechnology - methods; carbon; Carbon dioxide; Carbon Dioxide - metabolism; carbon dioxide enrichment; Carbon sequestration; fatty acid composition; Flue gas; gases; homeostasis; Life Sciences; Metabolism; Microalgae; Microalgae - metabolism; Microalgae - physiology; Microbiology; new species; Photosynthesis; protons; Review; concentrating mechanism; Response of lipid metabolism; Biomitigation; CO; Microalga; pH homeostasis
• ISSN: 0141-5492; 1573-6776; 1573-6776
• DOI: 10.1007/s10529-013-1274-7

Recent developments in the field of microalgal biotechnology, including CO₂ biomitigation and the discovery of new species of microalgae that are tolerant to extremely high CO₂ levels (40–100 vol%), have renewed interest in the physiological effects and mechanisms of high-CO₂ tolerance in photoautotrophs. Photosynthetic apparatus state transitions that increase ATP generation, upregulation of H⁺-ATPases pumping protons out of the cell, rapid shutdown of CO₂-concentrating mechanisms, and adjustment of membranes’ fatty acid composition are currently believed to be the key mechanisms governing cellular pH homeostasis and hence microalgae’s tolerance to high CO₂ levels, which is especially characteristic of extremophile and symbiotic species. The mechanisms governing acclimation to high CO₂ comprise the subject of this review and are discussed in view of the use of CO₂ enrichment to increase the productivity of microalgal cultures, as well as the practice of carbon capture from flue gases.