Fri 19 Jun 2009
Yes, all the magnetic posts are leading somewhere. I will get there soon.
From http://www.sciencedaily.com/releases/2005/11/051121102345.htm
Researchers Uncover How A Nanoscale ‘Compass’ Inside Bacteria Orients Them To The Earth’s Magnetic Field
ScienceDaily (Nov. 21, 2005) — It is not only migratory birds that orient themselves to the magnetic field of the Earth. Also bacteria — supposedly “simple” organisms — have evolved to be able to take advantage of the magnetic field in their search for optimal living conditions.
Such “magnetotactic” microorganisms use a miniature, cellular compass made of a chain of single nanomagnets, called magnetosomes. The entire bacterium is oriented like a compass needle inside the magnetic field. Until now, it was not clear how the cells organise magnetosomes into a stable chain, against their physical tendency to collapse by magnetic attraction…
Cryoelectron tomography of a magnetotactic bacterium: a three-dimensional reconstruction of the interior of a Magnetospirillum gryphiswaldense cell. The cell membrane is blue, the magnetosome crystal red, and the surrounding vesicle yellow. The image makes it clear that both the membrane vesicle and the “mature” magnetosomes are strung like pearls on a chain along a filamentous structure (green), which is similar to a cytoskeleton. (Image: Max Planck Institute for Biochemistry)