Controlled Biomineralization of Magnetite (Fe₃O₄) and Greigite (Fe₃S₄) in a Magnetotactic Bacterium

Authors

Dennis A. Bazylinski
Richard B. Frankel
Brigid R. Heywood
Stephen Mann
John W. King, University of Rhode IslandFollow
Percy L. Donaghay, University of Rhode IslandFollow
Alfred K. Hanson, University of Rhode Island

Document Type

Article

Date of Original Version

1994

Department

Oceanography

Abstract

A slowly moving, rod-shaped magnetotactic bacterium was found in relatively large numbers at and below the oxic-anoxic transition zone of a semianaerobic estuarine basin. Unlike all magnetotactic bacteria described to date, cells of this organism produce single-magnetic-domain particles of an iron oxide, magnetite (Fe₃O₄), and an iron sulfide, greigite (Fe₃S₄), within their magnetosomes. The crystals had different morphologies, being arrowhead or tooth shaped for the magnetite particles and roughly rectangular for the greigite particles, and were coorganized within the same chain(s) in the same cell with their long axes along the chain direction. Because the two crystal types have different crystallochemical characteristics, the findings presented here suggest that the formation of the crystal types is controlled by separate biomineralization processes and that the assembly of the magnetosome chain is controlled by a third ultrastructural process. In addition, our results show that in some magnetotactic bacteria, external environmental conditions such as redox and/or oxygen or hydrogen sulfide concentrations may affect the composition of the nonmetal part of the magnetosome mineral phase.

Citation/Publisher Attribution

Bazylinski, D. A., Frankel, R. B., Heywood, B. R., Mann, S., King, J. W., Donaghay, P. L., & Hanson, A. K. (1994). Controlled Biomineralization of Magnetite (Fe₃O₄) and Greigite (Fe₃S₄) in a Magnetotactic Bacterium. Appl. Environ. Microbiol., 61(9), 3231-3239. Retrieved from https://aem.asm.org/content/61/9/3232.

Available at: https://aem.asm.org/content/61/9/3232