Great Salt Lake organisms offer insight
May 28, 2006
The Associated Press
By Debbie Hummel
Extremophiles: Utah professors and students research UV protection and cleaning environment
The pink, brackish water of the north arm of Great Salt Lake is teaming with millions of microscopic organisms that could hold the key to better protection against ultraviolet rays or aid in environmental cleanup.
They're extremophiles - organisms that live in extreme environments, in this case, a saturated saline solution - and have gone largely unexamined until now. A new generation of college professors and their undergraduate students are unlocking their mysteries.
Bonnie Baxter, an assistant biology professor at Westminster College in Salt Lake City, set out with her students to find organisms that were highly resistant to UV radiation. The initial assumption was the pigments found in the creatures might have something to do with a greater protection from the sun.
''We had no real goal of isolating organisms,'' Baxter said. ''But when we found very little work had been done on the microbiology of Great Salt Lake we realized all of them are novel. They haven't been isolated before.''
What excites Baxter the most is that the work is being done by undergraduate students.
''These students have these incredibly cool experiments because they are working on organisms that have never been studied before,'' she said.
One of those students is Ashlee Allred. Under Baxter's supervision, Allred came upon just such a unique creature, one that is much more resistant to UV light damage than E. coli and other bacteria. She said the organism is able to use light but without experiencing damage to its DNA. The ''photoprotective'' characteristics appear to come from carotenoid pigments, like those found in carrots or sweet potatoes. Further study could lead to advancements in sunscreen technology, Baxter said.
Allred's sun- and salt-loving find was included in Canadian author Elin Kelsey's book, Strange New Species: Astonishing Discoveries of Life on Earth. Baxter said she is proposing Halorubrum salsosis as the organism's scientific name.
Baxter said she and her students have found genetic evidence for about 45 different organisms and have isolated about 25 of them. It will take some time to figure out how many others could be unique species.
Baxter and her colleagues hope to coordinate their research with that being done by two other Utah universities, Weber State in Ogden and Brigham Young in Provo. The three schools have plans to present a combined paper - a rarity in the academic world where the pressure to publish snuffs out such collaboration, they say.
''We must have between 400 and 500 different DNA isolates,'' said Alan Harker, a biology professor at Brigham Young University. He estimated less than 10 percent of those matched sequences are already in national databases.
Each of the schools have similar findings and are working to classify them, he said. All the professors agree that the unique microbiology of Great Salt Lake gives their students a leg up when it comes to getting into graduate and professional schools.
Until recent years, very little research has been done on the microbiology of Great Salt Lake, and Baxter attributes the lack of interest to a ''historical disgust'' of the salty, smelly landlocked sea. It's easy to understand why early settlers were disappointed to find a lake saltier than the ocean that contained no visible marine life.
''When I moved here to Utah it just seemed natural that someone ought to be studying the lake because it's such a unique environment,'' Harker said.
For years the lake was viewed as a cesspool, he said.
A railroad causeway cuts through the Great Salt Lake. Most tributaries flow into the south end of the lake, but with no outlet. It's a dead sea and the southern waters have a salt content of between 14 percent and 18 percent. Ocean water is about 3 percent. Due to the causeway, the northern section of the lake's salt content hovers in the high 20s.
Not only are the microbes living in the north section of the lake fascinating for their ability to live in such a high saline environment, they also live among oil seeps and years of pollution that have left traces of phosphorus and heavy metals, such as mercury and selenium, in the water.
''All of that feeds into the microbial community, and it's fairly important to know what those transformations are,'' said Harker.
On an overcast spring day, Harker and honors student Eric Barker, a junior, spent part of the morning capturing samples of water and soil from the lake bed near the decaying pilings of an old oil operation.
''We know there's a lot of oil, and we know what the oil content is in the sand,'' Harker said while screwing the lids on jelly jars filled with cloudy pink water and sand.
Barker will use the samples for research toward his honors thesis. With the help of his professor, he hopes to demonstrate that the microbes in that part of the lake are using the oil as a source of carbon.
Harker says it's research that could ultimately lead to advancements in how to clean the waste water from petroleum production, which also has a high salt content.
Farther north along the shoreline, closer to artist Robert Smithson's Earth artwork, ''Spiral Jetty,'' Weber State professor Craig Oberg and assistant professor Michele Zwolinski monitor four students as they get samples for their planned studies of how microorganisms in the lake use phosphorous.
''Phosphates are a big problem,'' Oberg said. ''These would have a unique [application] if we can find a protein that scavenges phosphates efficiently.''
Another colleague of Oberg's is working on what the organisms do with some of the lake's other contaminants.
''It's really not sterile at all,'' said Oberg. ''It has this huge biomass in it. But the biomass is microscopic.''