Magnetic Bacteria? - Magnetotactic Baceria!
by Sandi Clement
In nature, organisms use a variety of methods to figure out where they are and where they need to be going. Plants use sunlight and the force of gravity to determine which direction they should grow, birds migrate in part using the sun and stars to guide their path, and we humans can simply ask for directions at the nearest gas station.
Some organisms use the earth’s geomagnetic field to orient themselves and navigate through their environment. Organisms that use the earth’s geomagnetic field have some type of internal compass. The smallest organisms that use this navigational method are called magnetotactic bacteria.
Magnetotactic bacteria were discovered in 1975 by Richard P. Blakemore. Blakemore noticed that some of the bacteria that he observed under a microscope always moved to the same side of the slide. If he held a magnet near the slide, the bacteria would move towards the north end of the magnet.
These bacteria are able to do this because they make tiny, iron-containing, magnetic particles. Each of these particles is a magnet with a north pole and a south pole. The bacteria arrange these tiny magnets in a line to make one long magnet. They use this magnet as a compass to align themselves to the earth’s geomagnetic field…
(read more: The Curious Microbe)
(image: Biomagnetism Group, Univ. of Munich)
