Sphaerotilus natans, a Neutrophilic Iron-Related Sheath-Forming Bacterium: Perspectives for Metal Remediation Strategies

Abstract

Sphaerotilus natans is a neutrophilic sheath-forming microorganism from the Sphaerotilus-Leptothrix group of iron-related bacteria, known to form bacteriogenic iron oxides (BIOS) frequently deposited on cell surfaces as well as on sheaths and extracellular polymeric substances. S. natans has been reported to be an excellent sorbent for inorganic pollutants, either due to direct sorption onto biological surfaces or due to sorption onto BIOS. However, its filaments can cause bulking problems in wastewater treatment plants. This article promotes the potential applications of Sphaerotilus natans in bioremediation by reviewing its physiology and the fundamental understanding of sheath-forming mechanisms as well as iron biomineralization processes.

Keywords:

• bacteriogenic iron oxides
• biomineralization
• bioremediation
• heavy metals
• iron-related bacteria
• radionuclides

Acknowledgments

The authors would like to thank the European Commission for providing financial support through the Erasmus Mundus Joint Doctorate Programme ETeCoS³(Environmental Technologies for Contaminated Solids, Soils and Sediments) under the grant agreement FPA No. 2010-0009. Marina Seder-Colomina is a Doctoral Research Fellow of the ETeCoS³programme.