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

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.