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Updated: May 4, 2026

Purification of the M. magneticum Strain AMB-1 Magnetosome Associated Protein MamAΔ41

Purification of the M. magneticum Strain AMB-1 Magnetosome Associated Protein MamAΔ41

Published on: March 25, 2010

個々のMagnetospirillum gryphiswaldense細胞の磁気特性

Mathias M Claus^1,2, Marcus Wyss¹, Dirk Schüler³

¹University of Basel, Swiss Nanoscience Institute, Klingelbergstrasse 82, 4056 Basel, Switzerland.

Physical review. E

|February 20, 2026

Abstract:

Many bacteria share the fascinating ability to sense Earth's magnetic field-a process known as magnetotaxis. These bacteria synthesize magnetic nanoparticles, called magnetosomes, within their own cell body and arrange them to form a linear magnetic chain. The chain, which behaves like a compass needle, aligns the microorganisms with the geomagnetic field. Here, we measure the magnetic hysteresis of an individual bacterium of the species Magnetospirillum gryphiswaldense via ultrasensitive torque magnetometry. These measurements, in combination with transmission electron microscopy and micromagnetic simulations, reveal the magnetic configurations of the magnetosomes, their progression as a function of applied field, as well as the total remanent magnetic moment and effective magnetic anisotropy of a chain within a single bacterium. Knowledge of these properties is crucial both for understanding the mechanisms behind magnetotaxis and for the design of systems exploiting magnetotactic bacteria in biomedical applications.

キーワード:

走化性磁性体磁気特性生物医学的応用

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Collection, Isolation and Enrichment of Naturally Occurring Magnetotactic Bacteria from the Environment

Collection, Isolation and Enrichment of Naturally Occurring Magnetotactic Bacteria from the Environment

Published on: November 15, 2012

Growing Magnetotactic Bacteria of the Genus Magnetospirillum: Strains MSR-1, AMB-1 and MS-1

Growing Magnetotactic Bacteria of the Genus Magnetospirillum: Strains MSR-1, AMB-1 and MS-1

Published on: October 17, 2018

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