Microbial Sunscreens

You may have heard that it is important to wear sunscreen lotion when you go outside; this is because sunscreens protect our skin from dangerous ultraviolet sun rays. Surely, not all organisms put on sunscreen as humans do. Instead, many forms of life use pigments. Pigments have multiple functions in biology, including visual communication, protection, and regulation of body temperature. In this case, pigments act as natural sunscreens, giving organisms their distinct colors along the way. These pigments function as sunscreens by absorbing radiation and dissipating it in form of heat. One pigment that helps protect organisms against too much UV sunlight is melanin. Melanin can be found on human skin, in plants, and also in microscopic fungi and bacteria! Microbial melanin not only protects against UV light but also against X-rays, gamma-rays, and a plethora of different environmental stresses, including heat stress. Scientists have slowly been learning how to use fungal melanin for our benefit. Fungal melanin’s special properties can be used to clean up polluted wastewaters, for example. Scientists are currently working to see if fungal melanin can be used to protect astronauts from radiation while they are in space.