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Updated: Jul 5, 2025
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Growing Magnetotactic Bacteria of the Genus Magnetospirillum: Strains MSR-1, AMB-1 and MS-1
Published on: October 17, 2018
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Swimming polarity inversion in uncultured magnetotactic cocci
Giovanny Angiolillo1, Fernanda Abreu2, Daniel Acosta-Avalos3
1Centro Brasileiro de Pesquisas Fisicas-CBPF, Rua Xavier Sigaud 150, Urca, Rio de Janeiro, RJ, 22290-180, Brazil.
European Biophysics Journal : EBJ
|January 12, 2024
Summary
North-seeking (NS) magnetotactic bacteria exhibit distinct swimming behaviors and magnetic properties compared to South-seeking (SS) strains. These differences suggest an active magnetoreception mechanism beyond simple polarity switching.
Area of Science:
- Microbiology
- Biophysics
- Magnetism
Background:
- Magnetotactic bacteria (MTB) navigate using intracellular magnetic nanoparticles (magnetosomes) organized in chains.
- MTB exhibit South-seeking (SS) or North-seeking (NS) polarities, aligning with or against geomagnetic field lines.
- NS MTB can switch polarity in inhomogeneous magnetic fields, suggesting complex regulatory mechanisms.
Purpose of the Study:
- To investigate differences in swimming characteristics and magnetic moments between NS and SS magnetotactic cocci.
- To analyze magnetosome chain properties and bacterial magnetic moment in relation to polarity.
- To explore potential active magnetoreception processes in MTB.
Main Methods:
- Isolation of NS cocci from SS cocci strains.
- Recording bacterial trajectories to calculate velocity and swimming angle relative to magnetic fields.
- Microscopic analysis of magnetosome dimensions and calculation of individual bacterial magnetic moments.
Main Results:
- NS cocci displayed higher velocities compared to SS cocci.
- NS cocci showed narrower bacterial magnetic moment distributions and greater angular dispersion.
- NS cocci exhibited lower sensitivity to magnetic fields than SS cocci.
Conclusions:
- Observed differences in NS and SS cocci cannot be solely attributed to magnetosome chain polarity changes.
- The findings support the hypothesis of an active magnetoreceptive process in magnetotactic bacteria.
- Further research is needed to elucidate the mechanisms underlying active magnetoreception in MTB.
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