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Growing Magnetotactic Bacteria of the Genus Magnetospirillum: Strains MSR-1, AMB-1 and MS-1
Published on: October 17, 2018
Magnetosome chain superstructure in uncultured magnetotactic bacteria
Leida G Abraçado1, Fernanda Abreu, Carolina N Keim
1Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, CCS, bloco F, Cidade Universitária, 21941-902, Rio de Janeiro, Brazil.
Physical Biology
|January 8, 2011
Summary
Magnetotactic bacteria exhibit precise magnetosome chain organization, with crystals precisely rotated relative to neighbors. This specific arrangement may serve as a biosignature for magnetofossils.
Area of Science:
- Biomineralization
- Microbiology
- Geobiology
Background:
- Magnetotactic bacteria produce magnetosomes, membrane-bound magnetic particles, for navigation via magnetotaxis.
- Existing knowledge recognizes two organizational levels: intracellular vesicle control of mineral properties and chain formation within the cell.
Purpose of the Study:
- To investigate an additional, previously undescribed level of magnetosome organization in uncultured magnetotactic cocci.
- To analyze the precise orientation of magnetosomes within chains.
Main Methods:
- Electron microscopy with goniometer analysis was employed to examine magnetosome chains.
- Crystallographic orientations of individual magnetosomes within chains were meticulously analyzed.
Main Results:
- Magnetosomes within chains are not randomly oriented but exhibit specific rotational alignments (60°, 180°, 300°) relative to neighbors.
- This precise arrangement leads to the overlapping of crystal capping faces between adjacent magnetosomes.
- The findings suggest the presence of specific genetic factors controlling this ordered structure.
Conclusions:
- A novel level of magnetosome chain organization, characterized by precise inter-crystal orientation, has been identified.
- This specific crystalline symmetry could function as a biosignature in the study of magnetofossils.
- Further research into the genetic determinants of this precise organization is warranted.
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