Magnetotactic Protists at the Oxic–Anoxic Transition Zones of Coastal Aquatic Environments
Magnetotactic protists of different types have been sporadically observed in a number of aquatic habitats, mainly at the oxic–anoxic transition zone of chemically stratified coastal environments and the anoxic zone. Cells of those examined contained magnetite (Fe3O4) crystals whose size and shape are close to those of magnetotactic bacteria. While some appear to biomineralize their magnetic crystals, others clearly ingest magnetotactic bacteria, with some egesting indigestible remains of these prokaryotes. Magnetotactic protists show a great potential for iron cycling in chemically stratified environments. Many questions remain to be answered regarding these interesting microorganisms.
KeywordsMagnetic Field Line Magnetic Mineral Magnetic Dipole Moment Anoxic Zone Magnetotactic Bacterium
We are grateful to K.J. Edwards, S.S. Epstein, M. Pósfai, and S.L. Simmons for their collaboration in this work. DAB and CTL are supported by U.S. National Science Foundation grant EAR-0920718.
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