Experimental ocean acidification alters the allocation of metabolic energy

• Main Authors: Francis Pan, T C, Applebaum, Scott L, Manahan, Donal T
• Format: Dataset
• Language: English
• Published: PANGAEA 2015
• Subjects: Age; Alkalinity; total; standard error; Animalia; Aragonite saturation state; Bicarbonate ion; Body length; standard deviation; Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Containers and aquaria (20-1000 L or < 1 m**2); Coulometric titration; Echinodermata; Feeding mode; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Gene expression (incl. proteomics); Growth/Morphology; In vivo Sodium; Potassium; adenosine triphosphatase activity per individual; Laboratory experiment; Not applicable; OA-ICC; Ocean Acidification International Coordination Centre; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Pelagos; Percentage; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.847832; https://doi.org/10.1594/PANGAEA.847832

Energy is required to maintain physiological homeostasis in response to environmental change. Although responses to environmental stressors frequently are assumed to involve high metabolic costs, the biochemical bases of actual energy demands are rarely quantified. We studied the impact of a near-future scenario of ocean acidification [800 µatm partial pressure of CO2 (pCO2)] during the development and growth of an important model organism in developmental and environmental biology, the sea urchin Strongylocentrotus purpuratus. Size, metabolic rate, biochemical content, and gene expression were not different in larvae growing under control and seawater acidification treatments. Measurements limited to those levels of biological analysis did not reveal the biochemical mechanisms of response to ocean acidification that occurred at the cellular level. In vivo rates of protein synthesis and ion transport increased 50% under acidification. Importantly, the in vivo physiological increases in ion transport were not predicted from total enzyme activity or gene expression. Under acidification, the increased rates of protein synthesis and ion transport that were sustained in growing larvae collectively accounted for the majority of available ATP (84%). In contrast, embryos and prefeeding and unfed larvae in control treatments allocated on average only 40% of ATP to these same two processes. Understanding the biochemical strategies for accommodating increases in metabolic energy demand and their biological limitations can serve as a quantitative basis for assessing sublethal effects of global change. Variation in the ability to allocate ATP differentially among essential functions may be a key basis of resilience to ocean acidification and other compounding environmental stressors.