Seawater carbonate chemistry and motility of flagellated microalgae

• Main Authors: Wang, Yitao, Fan, Xiao, Gao, Guang, Beardall, John, Inaba, Kazuo, Hall-Spencer, Jason M, Xu, Dong, Zhang, Xiaowen, Han, Wentao, McMinn, Andrew, Ye, Naihao
• Format: Dataset
• Language: English
• Published: PANGAEA 2020
• Subjects: Alkalinity; total; standard error; Aragonite saturation state; Behaviour; Bicarbonate ion; Bottles or small containers/Aquaria (<20 L); Calcite saturation state; Calcium; flux; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Chlamydomonas reinhardtii; Chlorophyta; Daily vertical migration; Dunaliella salina; Figure; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Gene expression; Gene name; Irradiance; Laboratory experiment; Laboratory strains; Microglena sp.; Move velocity; Not applicable; OA-ICC; Ocean Acidification International Coordination Centre; Oxygen evolution; per chlorophyll a; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.925549; https://doi.org/10.1594/PANGAEA.925549

Motility plays a critical role in algal survival and reproduction, with implications for aquatic ecosystem stability. However, the effect of elevated CO2 on marine, brackish and freshwater algal motility is unclear. Here we show, using laboratory microscale and field mesoscale experiments, that three typical phytoplankton species had decreased motility with increased CO2. Polar marine Microglena sp., euryhaline Dunaliella salina and freshwater Chlamydomonas reinhardtii were grown under different CO2 concentrations for 5 years. Long-term acclimated Microglena sp. showed substantially decreased photo-responses in all treatments, with a photophobic reaction affecting intracellular calcium concentration. Genes regulating flagellar movement were significantly downregulated (P < 0.05), alongside a significant increase in gene expression for flagellar shedding (P < 0.05). D. salina and C. reinhardtii showed similar results, suggesting that motility changes are common across flagellated species. As the flagella structure and bending mechanism are conserved from unicellular organisms to vertebrates, these results suggest that increasing surface water CO2 concentrations may affect flagellated cells from algae to fish.