RECYCLING OF METABOLIZED IRON BY THE MARINE DINOFLAGELLATE AMPHIDINIUM CARTERAE.

Senescent, iron-limited cultures of Amphidinium carterae Hulburt were used to detect the presence of iron made available for phytoplankton growth by recycling of metabolized iron from disrupted cells. Both physical disruption of cells and physical disruption plus exposure to a low pH were tested. The test cultures remained viable over long period of time, and were stimulated to full growth by the additions of Fe, but not by the addition of any other nutrients. Simple physical disruption of cells caused only a very slow release of available Fe, but not by the addition of any other nutrients. Simple physical disruption of cells caused only a very slow release of available Fe. It is suggested that the digestive processes of herbivores are instrument in the rapid regeneration of Fe as a nutrient available for phytoplankton growth. [ABSTRACT FROM AUTHOR]