Ocean acidification may increase the amount of metabolic energy necessary for marine organisms to maintain normal cell functions, according to a study. Although the effect of ocean acidification on whole organism growth appears to be minimal, reduced seawater pH may impose a metabolic cost. Donal T. Manahan and colleagues grew larvae of sea urchins under both normal and acidic seawater conditions. While indicators of whole-organism growth and metabolism, such as size, metabolic rate, and gene expression did not differ between larvae grown under different conditions, cellular responses differed. Larvae grown in acidic water displayed around 50% higher rates of ion transport and protein synthesis than other larvae. The energy demands of such high rates of transport and synthesis accounted for 84% of the available ATP, the cellular energy currency, in larvae grown in acidic water, whereas larvae grown in normal seawater devoted only 40% of available ATP to the two processes. The results suggest that although ocean acidification may not exert lethal effects on marine organisms, coping with changing seawater chemistry may consume a significant amount of an organism’s metabolic energy, according to the authors.
Article #14-16967: “Experimental ocean acidification alters the allocation of metabolic energy,” by T.-C. Francis Pan, Scott L. Applebaum, and Donal T. Manahan.
MEDIA CONTACT: Donal T. Manahan, Department of Biological Sciences, University of Southern California, Los Angeles, CA; tel: 213-740-5793; e-mail: manahan(at)usc.edu
PNAS, via EurekAlert, 31 March 2015. Press release.
