Showing papers on "Magnetotactic bacteria published in 1984"
TL;DR: A new extraction technique now permits ultrafine magnetite crystals to be separated from a variety of deep-sea sediments as mentioned in this paper, revealing the presence of several distinct crystal types, some of which closely resemble those formed by the magnetotactic bacteria.
Abstract: A new extraction technique now permits ultrafine magnetite crystals to be separated from a variety of deep-sea sediments. Morphologic characterization of these particles with transmission electron microscopy reveals the presence of several distinct crystal types, some of which closely resemble those formed by the magnetotactic bacteria. The apparently biogenic magnetite particles are of single-domain size and dominate the population in calcareous deep-sea sediments. Bacterially precipitated magnetite may therefore be a major source of the stable magnetic remanence in some marine sediments. These objects possibly constitute the smallest mineral fossils yet recovered from the sedimentary record.
161 citations
TL;DR: Diffusive motions of the magnetosomes (enveloped Fe3O4 particles) in the magnetotactic bacterium Aquaspirillum Magnetotacticum result in a very broad-line Mössbauer spectrum above freezing temperatures.
39 citations
Patent•
22 Jun 1984
TL;DR: A method for detecting or removing a substance in a medium is presented in this article, where magnetic material, particularly magnetic bacteria or magnetic particles contained therein, are treated to render them receptive to binding or attachment to the substance sought to be detected or removed.
Abstract: A method for detecting or removing a substance in a medium is presented. Magnetic material, particularly magnetic bacteria or magnetic particles contained therein, are treated to render them receptive to binding or attachment to the substance sought to be detected or removed. Following binding or attachment to the treated magnetic material, the medium is subjected to a magnetic field, which results in removal of the magnetic material and the substance bound or attached thereto.
30 citations
TL;DR: The magnetotactic bacterium A. magnetoticum contains ferrous ions, a low density hydrous ferric oxide (ferrihydrite), and Fe $\_3$ O $\_4$, which is precipitated by partial reduction of the ferrihydite precursor as discussed by the authors.
Abstract: The magnetotactic bacterium A. magnetotacticum contains ferrous ions, a low density hydrous ferric oxide, a high density hydrous ferric oxide (ferrihydrite) and Fe $\_3$ O $\_4$ , which is precipitated by partial reduction of the ferrihydrite precursor.
26 citations
01 Feb 1984
TL;DR: The vertical component of the inclined geomagnetic field selects the predominant polarity in each hemisphere by presumably favouring those cells whose polarity causes them to be directed downward towards the sediments and away from the toxic effects of the oxygen rich surface waters.