Please Pass the Salt: the World of Halophiles

Halophiles are salt-loving organisms. They live in ultra-salty water, like the Dead Sea and the Great Salt Lake in Utah. These bodies of water can be eight times saltier than the ocean. One example of a halophile is the brine shrimp.

All living things need SOME salt, but too much can be deadly. Too much salt causes a cells proteins to stop working and too little salt can cause the cell to dehydrate. But halophiles have adapted to this extreme environment by using pumps in their cell membranes to get rid of the salt. They have other molecules that help keep the water in their cells.

Many salt lakes are also alkaline (having a pH of 8 or more).

Usually, halophiles have the place to themselves. However, recently the Great Salt Lake has gotten less salty as meltwater from large amounts of snow has entered it. This has allowed other organisms, such as the to boatman shown below, move in and devour the brine shrimp.

Halophiles have a few interesting uses. Some people eat Spirulina, a halophilic blue green algae that pile up at the side of salt lakes. It is sold in health food stores as a high-protein powder. YUM!

Halophiles also make the protein bacteriorhodopsin. When exposed to light, it creates an electrical charge allowing cells to pump salt out. Since it also changes shape and color, scientists are working on a way to use this protein in face identification software.