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Growing Magnetotactic Bacteria of the Genus Magnetospirillum: Strains MSR-1, AMB-1 and MS-1
Published on: October 17, 2018
Magnetic optimization in a multicellular magnetotactic organism
Michael Winklhofer1, Leida G Abraçado, Alfonso F Davila
1Department of Earth and Environmental Science, Ludwig-Maximilians-University of Munich, Munich, Germany. michaelw@lmu.edu
Biophysical Journal
|October 31, 2006
Summary
Multicellular magnetotactic prokaryotes exhibit high magnetic optimization (DMO > 80%), suggesting a complex life cycle. This level of magnetic alignment is unlikely to arise from random cell organization.
Area of Science:
- Microbiology
- Biophysics
- Geomicrobiology
Background:
- Unicellular magnetotactic prokaryotes are known for their magnetic optimization.
- These organisms possess chains of magnetic particles (magnetosomes) within their cells.
Purpose of the Study:
- To investigate the magnetic properties of a multicellular magnetotactic prokaryote (MMP).
- To determine the degree of magnetic optimization (DMO) in MMPs and understand the coherence of magnetic moments within their cellular chains.
Main Methods:
- Magnetic measurements using a highly sensitive technique (1 fAm(2)) on individual MMPs.
- Numerical modeling to simulate magnetic dipole orientations and assess DMO probabilities.
- Simulation of aggregation and self-organization scenarios for magnetic cells.
Main Results:
- MMPs consistently showed a high DMO, exceeding 80%.
- Numerical modeling indicated a very low probability (0.017) of achieving such high DMOs with randomly oriented magnetic dipoles.
- Scenarios involving aggregation or self-organization did not consistently explain the observed high DMOs.
Conclusions:
- The high DMO in MMPs suggests strong evolutionary selection pressures.
- A sophisticated reproduction mechanism is likely involved in maintaining magnetic alignment across generations.
- A multicellular life cycle is proposed as the most plausible explanation for the transmission of high DMO in MMPs.
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