Hydrogen peroxide production driven by UV-B in planktonic microorganisms: A photocatalytic factor in sea warming and ice melting in regions with ozone depletion?

Abstract

UV-B radiation activates the synthesis of hydrogen peroxide from water and oxygen in many protein kinds, which having been discovered initially in antibodies, has been so far applied to explore new mechanisms in relation to immune defence. As shown here, the natural association of this common photocatalysis and catalase transforms UV-B photons into heat in a cyclic reaction that represents in biology a basic defence mechanism against UV-B radiation and cold, the activity of which drives the buoyancy and production of planktonic microorganisms in cold oceans. Moreover, given that UV-B radiation reaching the Earth's surface depends mainly on changes in the ozone layer, that defence mechanism over-activated by ozone depletion in microorganisms gathered at the top layer of the water column during seasonal production could result in accelerated sea ice melting, surface warming and ecosystem changes, such as is happening at high latitudes. Thus, one concludes that UV-B-driven photoproduction and decomposition of hydrogen peroxide in plankton can be a new, hidden biogeochemical process under control of the ozone layer with important effects on the ecosystem and climate. © 2011 The Author(s).