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Controlled biomineralization of magnetite (Fe3O4) and greigite (Fe3S4) in a magnetotactic bacterium
journal contribution
posted on 2023-05-18, 14:18 authored by Bazylinski, DA, Frankel, RB, Heywood, BR, Mann, S, King, JW, Donaghay, PL, Hanson, AKA 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.
History
Publication title
Applied and Environmental MicrobiologyVolume
61Issue
9Pagination
3232-3239ISSN
0099-2240Publisher
Amer Soc MicrobiologyPlace of publication
1752 N St NW, Washington, USA, DC, 20036-2904Rights statement
Copyright 1995 American Society for MicrobiologyRepository Status
- Restricted