Iron sulfides from magnetotactic bacteria: Structure, composition, and phase transitions

Mihály Pósfai, P R Buseck, Dennis A. Bazylinski, Richard B. Frankel

Research output: Contribution to journalArticle

153 Citations (Scopus)

Abstract

Using transmission electron microscopy, we studied the structures and compositions of Fe sulfides within cells of magnetotactic bacteria that were collected from natural habitats. Ferrimagnetic greigite (F3,S4) occurred in all types of sulfide-producing magnetotactic bacteria examined. Mackinawite (tetragonal FeS) and, tentatively, sphalerite-type cubic FeS were also identified. In contrast to earlier reports, we did not find pyrite (FeS2) or pyrrhotite (Fe1-xS). Mackinawite converted to greigite over time within the bacteria that were deposited on electron microscope grids and stored in air. Orientation relationships between the two minerals indicate that the cubic-close-packed S substructure remains unchanged during the transformation; only the Fe atoms rearrange. Neither mackinawite nor cubic FeS are magnetic, and yet they are aligned in chains such that when converted to magnetic greigite, the probable easy axis of magnetization, [100], is parallel to the chain direction. The resulting chains of greigite are ultimately responsible for the magnetic dipole moment of the cell. Both greigite and mackinawite magnetosomes can contain Cu, depending on the sampling locality. Because bacterial mackinawite and cubic FeS are unstable over time, only greigite crystals are potentially useful as geological biomarkers.

Original languageEnglish (US)
Pages (from-to)1469-1481
Number of pages13
JournalAmerican Mineralogist
Volume83
Issue number11-12 PART 2
StatePublished - 1998

Fingerprint

greigite
mackinawite
iron sulfide
Sulfides
phase transition
bacteria
sulfides
Bacteria
Iron
Phase transitions
iron
bacterium
Chemical analysis
pyrrhotite
habitats
biomarkers
zincblende
pyrites
substructures
cells

ASJC Scopus subject areas

  • Geochemistry and Petrology
  • Geophysics

Cite this

Pósfai, M., Buseck, P. R., Bazylinski, D. A., & Frankel, R. B. (1998). Iron sulfides from magnetotactic bacteria: Structure, composition, and phase transitions. American Mineralogist, 83(11-12 PART 2), 1469-1481.

Iron sulfides from magnetotactic bacteria : Structure, composition, and phase transitions. / Pósfai, Mihály; Buseck, P R; Bazylinski, Dennis A.; Frankel, Richard B.

In: American Mineralogist, Vol. 83, No. 11-12 PART 2, 1998, p. 1469-1481.

Research output: Contribution to journalArticle

Pósfai, M, Buseck, PR, Bazylinski, DA & Frankel, RB 1998, 'Iron sulfides from magnetotactic bacteria: Structure, composition, and phase transitions', American Mineralogist, vol. 83, no. 11-12 PART 2, pp. 1469-1481.
Pósfai, Mihály ; Buseck, P R ; Bazylinski, Dennis A. ; Frankel, Richard B. / Iron sulfides from magnetotactic bacteria : Structure, composition, and phase transitions. In: American Mineralogist. 1998 ; Vol. 83, No. 11-12 PART 2. pp. 1469-1481.
@article{a74995ca2db244d5b2834dbce5e27a1f,
title = "Iron sulfides from magnetotactic bacteria: Structure, composition, and phase transitions",
abstract = "Using transmission electron microscopy, we studied the structures and compositions of Fe sulfides within cells of magnetotactic bacteria that were collected from natural habitats. Ferrimagnetic greigite (F3,S4) occurred in all types of sulfide-producing magnetotactic bacteria examined. Mackinawite (tetragonal FeS) and, tentatively, sphalerite-type cubic FeS were also identified. In contrast to earlier reports, we did not find pyrite (FeS2) or pyrrhotite (Fe1-xS). Mackinawite converted to greigite over time within the bacteria that were deposited on electron microscope grids and stored in air. Orientation relationships between the two minerals indicate that the cubic-close-packed S substructure remains unchanged during the transformation; only the Fe atoms rearrange. Neither mackinawite nor cubic FeS are magnetic, and yet they are aligned in chains such that when converted to magnetic greigite, the probable easy axis of magnetization, [100], is parallel to the chain direction. The resulting chains of greigite are ultimately responsible for the magnetic dipole moment of the cell. Both greigite and mackinawite magnetosomes can contain Cu, depending on the sampling locality. Because bacterial mackinawite and cubic FeS are unstable over time, only greigite crystals are potentially useful as geological biomarkers.",
author = "Mih{\'a}ly P{\'o}sfai and Buseck, {P R} and Bazylinski, {Dennis A.} and Frankel, {Richard B.}",
year = "1998",
language = "English (US)",
volume = "83",
pages = "1469--1481",
journal = "American Mineralogist",
issn = "0003-004X",
publisher = "Mineralogical Society of America",
number = "11-12 PART 2",

}

TY - JOUR

T1 - Iron sulfides from magnetotactic bacteria

T2 - Structure, composition, and phase transitions

AU - Pósfai, Mihály

AU - Buseck, P R

AU - Bazylinski, Dennis A.

AU - Frankel, Richard B.

PY - 1998

Y1 - 1998

N2 - Using transmission electron microscopy, we studied the structures and compositions of Fe sulfides within cells of magnetotactic bacteria that were collected from natural habitats. Ferrimagnetic greigite (F3,S4) occurred in all types of sulfide-producing magnetotactic bacteria examined. Mackinawite (tetragonal FeS) and, tentatively, sphalerite-type cubic FeS were also identified. In contrast to earlier reports, we did not find pyrite (FeS2) or pyrrhotite (Fe1-xS). Mackinawite converted to greigite over time within the bacteria that were deposited on electron microscope grids and stored in air. Orientation relationships between the two minerals indicate that the cubic-close-packed S substructure remains unchanged during the transformation; only the Fe atoms rearrange. Neither mackinawite nor cubic FeS are magnetic, and yet they are aligned in chains such that when converted to magnetic greigite, the probable easy axis of magnetization, [100], is parallel to the chain direction. The resulting chains of greigite are ultimately responsible for the magnetic dipole moment of the cell. Both greigite and mackinawite magnetosomes can contain Cu, depending on the sampling locality. Because bacterial mackinawite and cubic FeS are unstable over time, only greigite crystals are potentially useful as geological biomarkers.

AB - Using transmission electron microscopy, we studied the structures and compositions of Fe sulfides within cells of magnetotactic bacteria that were collected from natural habitats. Ferrimagnetic greigite (F3,S4) occurred in all types of sulfide-producing magnetotactic bacteria examined. Mackinawite (tetragonal FeS) and, tentatively, sphalerite-type cubic FeS were also identified. In contrast to earlier reports, we did not find pyrite (FeS2) or pyrrhotite (Fe1-xS). Mackinawite converted to greigite over time within the bacteria that were deposited on electron microscope grids and stored in air. Orientation relationships between the two minerals indicate that the cubic-close-packed S substructure remains unchanged during the transformation; only the Fe atoms rearrange. Neither mackinawite nor cubic FeS are magnetic, and yet they are aligned in chains such that when converted to magnetic greigite, the probable easy axis of magnetization, [100], is parallel to the chain direction. The resulting chains of greigite are ultimately responsible for the magnetic dipole moment of the cell. Both greigite and mackinawite magnetosomes can contain Cu, depending on the sampling locality. Because bacterial mackinawite and cubic FeS are unstable over time, only greigite crystals are potentially useful as geological biomarkers.

UR - http://www.scopus.com/inward/record.url?scp=0032440750&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0032440750&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0032440750

VL - 83

SP - 1469

EP - 1481

JO - American Mineralogist

JF - American Mineralogist

SN - 0003-004X

IS - 11-12 PART 2

ER -