Interspecific variability in phosphorus-induced lipid remodeling among marine eukaryotic phytoplankton

• Published in: The New phytologist 2017-01, Vol.213 (2), p.700-713
• Main Authors: José Pedro Cañavate, Armada, Isabel, Ismael Hachero‐Cruzado
• Format: Article
• Language: English
• Subjects: Algae; Analysis of Variance; Aquatic microorganisms; Aquatic Organisms - drug effects; Aquatic Organisms - metabolism; Availability; Betaine; betaine lipids; Depletion; Deprivation; Diglycerides; ecology; Eukaryota - drug effects; Eukaryota - metabolism; Interspecific; Isochrysis galbana; lipid class; Lipids; Lipids - chemistry; Microalgae - drug effects; Microalgae - growth & development; Microalgae - metabolism; Phosphates - pharmacology; Phosphatidylglycerol; Phospholipids; Phosphorus; Phosphorus - metabolism; Phytoplankton; Phytoplankton - drug effects; Phytoplankton - metabolism; Plankton; Principal Component Analysis; Replenishment; Species; Species Specificity
• ISSN: 0028-646X; 1469-8137
• DOI: 10.1111/nph.14179

The response of marine microalgal lipids to phosphorus is of central importance in phytoplankton ecology but remains poorly understood. We determined how taxonomically diverse microalgal species remodelled their lipid class profile in response to phosphorus availability and whether these changes coincided with those already known to occur in land plants and in the limited number of phytoplankton species for which data are available. The complete lipid class profile and specific lipid ratios influenced by phosphorus availability were quantified in two green microalgae and seven Chromalveolates exposed to phosphorus repletion, deprivation and replenishment. Lipid class cell quota changes in the two green microalgae resembled the currently described pattern of betaine lipids substituting for phospholipids under phosphorus depletion, whereas only two of the studied Chromalveolates showed this pattern. Sulpholipids counter-balanced phosphatidylglycerol only in Picochlorum atomus. In all other species, both lipids decreased simultaneously under phosphorus deprivation, although sulpholipids declined more slowly. Phosphorus deprivation always induced a decrease in digalactosyl-diacylglycerol. However, the ratio of digalactosyl-diacylglycerol to total phospholipids increased in eight species and remained unchanged in Isochrysis galbana. Marine phytoplankton seems to have evolved a diversified mechanism for remodelling its lipid class profile under the influence of phosphorus, with cryptophytes and particularly haptophytes exhibiting previously unobserved lipid responses to phosphorus.