Magnetotactic Bacteria Finding Their Way

Magnetotactic Bacteria Finding Their Way

Before GPS, people found their way with a compass. Many still do. Did you know that finding your way is possible, even if you don’t have any eyes or ears, or even a brain, as long as you have a compass? Magnetotactic bacteria (MTB) use the magnetic field of planet Earth to know which way to go. To do that, they have to build a compass. Realize that these are single-cell organisms that live in marine or freshwater habitats.

Inside the cells of all living things, there are subunits called organelles that perform various functions. MTB have organelles called magnetosomes that contain magnetic crystals. They build the magnetosomes by digesting iron and combining the iron with sulfur to form iron sulfide or with oxygen to form iron oxide. The iron oxide is also known as magnetite, and it’s a powerful magnet.

The bacteria form chains of these magnetic crystals inside their cells. The magnetosome chain acts as a compass needle aligning the MTB to Earth’s magnetic field. In this way, the magnetotactic bacteria can “know” the direction to move. Why do these bacteria need to know directions? They are anaerobic bacteria, meaning that they survive without oxygen. Oxygen can be deadly to them, so they need to find an area away from it. Rather than blindly going around in circles looking for a safe place, they move in a straight line to their anaerobic safe zone.

In 1963, an Italian scientist first noticed certain bacteria aligning and moving in the direction of the north pole. It wasn’t until 2007 that scientists paid much attention to that observation. Without eyes, ears, or a brain, magnetotactic bacteria can find where they need to go. But without a brain, how can they know to do this? And how can a single-cell bacterium build the magnetosome organelles? These magnetic crystals are difficult for humans to create in a laboratory. In fact, scientists have found that the magnetite produced by bacteria is better for some applications than what the scientists can produce in the laboratory. For that reason, they are looking to find a way to mass-produce MTB to obtain their magnetosomes.

Who taught the magnetotactic bacteria this fantastic skill? Did one of them figure it out and then pass that knowledge on to future generations? We don’t think so. A better explanation is that the Master Designer programmed the skill into them.

You can read a scientific paper on MTB at THIS LINK. Leading evolutionary biologist J.B.S. Haldane (1892-1964) once said that if you could find a magnetic mechanism as part of a living organism, it would disprove evolution. You can read more about Haldane and his statement at THIS LINK.

— Roland Earnst © 2020