Using Bioluminescent Bacteria to Screen Sediment Pollution
Erik Olsen, New York Times, December 19, 2011
In Dr. Edith Widder's laboratory, sediment samples are mixed with a bioluminescent bacterium called Vibrio fischeri. Using a photometer to measure the light given off by the bacteria, Dr. Widder can quickly determine the concentration of toxic chemicals in the sediment by seeing how much and how quickly the light dims as the contaminants kill the bacteria. She is using this technique to detect heavy metals and nutrients, like phosphorus and nitrogen, in the Indian River Lagoon, a 156-mile estuary that scientists say is one of Florida’s most precious and threatened ecosystems.
Other organizations monitor the waters there, but Dr. Widder’s use of bioluminescent bacteria as a pollution marker and her system’s ability to do real-time monitoring are singular. Another homegrown project of Dr. Widder’s design is opening a new perspective on deep-sea life.
She draws animals to a special camera that is armed with a spinning dial of LED lights resembling the distress call of a species of bioluminescent jellyfish, Atolla wyvillei, that appears to use light as a kind of burglar alarm, luring predators to go after whatever is attacking it. In December 2009, her Eye-in-the-Sea camera was placed in 3,000 feet of water in the Monterey Canyon, a submarine canyon off the coast of California, where it remained for a year. The resulting videos, spanning about 5,300 hours, are being studied by researchers and graduate students at the Monterey Bay Aquarium, who have discovered numerous new behaviors of deep-sea animals.
Read the complete story, with photos and links to more information, in the NY Times.