Related Experiment Video
Updated: Mar 30, 2026

Growing Magnetotactic Bacteria of the Genus Magnetospirillum: Strains MSR-1, AMB-1 and MS-1
Published on: October 17, 2018
Magnetite defines a vertebrate magnetoreceptor
C E Diebel1, R Proksch, C R Green
1Experimental Biology Research Group, School of Biological Sciences, University of Auckland, New Zealand. m.walker@auckland.ac.nz
Abstract:
The key behavioural, physiological and anatomical components of a magnetite-based magnetic sense have been demonstrated in rainbow trout (Oncorhynchus mykiss). Candidate receptor cells located within a discrete sub-layer of the olfactory lamellae contained iron-rich crystals that were similar in size and shape to magnetite crystals extracted from salmon. Here we show that these crystals, which mapped to individual receptors using confocal and atomic force microscopy, are magnetic, as they are uniquely associated with dipoles detected by magnetic force microscopy. Analysis of their magnetic properties identifies the crystals as single-domain magnetite. In addition, three-dimensional reconstruction of the candidate receptors using confocal and atomic force microscopy imaging confirm that several magnetic crystals are arranged in a chain of about 1 microm within the receptor, and that the receptor is a multi-lobed single cell. These results are consistent with a magnetite-based detection mechanism, as 1-microm chains of single-domain magnetite crystals are highly suitable for the behavioural and physiological responses to magnetic intensity previously reported in the trout.
Related Concept Videos
Other Unique Bacteria
Magnetism
An individual magnetic pole cannot be isolated. No matter how small, every piece of a magnet contains a north pole and a south...
Ferromagnetism
Magnetic Fields
A magnetic field is defined by the force that a charged particle experiences...
Magnetic Susceptibility and Permeability
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
Potential Due to a Magnetized Object
The vector...

