Controlled biosynthesis of greigite (Fe3S4) in magnetotactic bacteria

Low-temperature magnetic properties of greigite (Fe3S4)

[1] We provide comprehensive low-temperature magnetic results for greigite (Fe3S4) across the spectrum from superparamagnetic (SP) to multidomain (MD) behavior. It is well known that greigite has no lowtemperature magnetic transitions, but we also document that it has strong domain-state dependence of magnetic properties at low temperatures. Blocking of SP grains and increasing thermal stabilit...

Structure, Morphology and Growth of Biogenic Greigite (Fe3S4)

A cultured greigite-producing magnetotactic bacterium in a novel group of sulfate-reducing bacteria.

Magnetotactic bacteria contain magnetosomes--intracellular, membrane-bounded, magnetic nanocrystals of magnetite (Fe(3)O(4)) or greigite (Fe(3)S(4))--that cause the bacteria to swim along geomagnetic field lines. We isolated a greigite-producing magnetotactic bacterium from a brackish spring in Death Valley National Park, California, USA, strain BW-1, that is able to biomineralize greigite and ...

Biologically Controlled Mineralization of Magnetic Iron Minerals by Magnetotactic Bacteria

The biomineralization of several magnetic iron minerals, including the iron oxide magnetite (Fe30 4 ; Fe 2I Fe/+04 ) and the iron sulfides greigite (Fe3S4 ) and pyrrhotite (Fe7SS)' can be mediated by bacteria as well as by other organisms. These minerals are known to be synthesized by procaryotes in one of two fundamentally different modes of biomineralization. The first is uncontrolled mineral...

Magnetic structure of greigite (Fe3S4) probed by neutron powder diffraction and polarized neutron diffraction

[1] We have investigated greigite (Fe3S4) using a combination of neutron powder diffraction and polarized neutron diffraction to give the first unambiguous assignment of its magnetic structure. Our results confirm that greigite has a collinear ferrimagnetic structure with antiferromagnetic coupling between the tetrahedral (A) and octahedral (B) sites. Our analysis also indicates that greigite d...