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Magnetosome dynamics in magnetotactic bacteria.

S Ofer·I Nowik·E R Bauminger·G C Papaefthymiou·R B Frankel·R P Blakemore
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Abstract

Diffusive motions of the magnetosomes (enveloped Fe3O4 particles) in the magnetotactic bacterium Aquaspirillum magnetotacticum result in a very broad-line Mössbauer spectrum (T approximately 100 mm/s) above freezing temperatures. The line width increases with increasing temperature. The data are analyzed using a bounded diffusion model to yield the rotational and translational motions of the magnetosomes as well as the effective viscosity of the material surrounding the magnetosomes. The results are [theta 2] l/2 less than 1.5 degrees and [x2] 1/2 less than 8.4 A for the rotational and translational motions, respectively, implying that the particles are fixed in whole cells. The effective viscosity is 10 cP at 295 K and increases with decreasing temperature. Additional Fe3+ material in the cell is shown to be associated with the magnetosomes. Fe2+ material in the cell appears to be associated with the cell envelope.

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Bacterial Physiological PhenomenaMagneticsMathematicsSpectrum AnalysisTemperatureJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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S Ofer, I Nowik, E R Bauminger, G C Papaefthymiou, R B Frankel, R P Blakemore. 1984. Magnetosome dynamics in magnetotactic bacteria.. https://doi.org/10.1016/s0006-3495(84)83998-3

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