We have been learning a greatdeal about biology’s survival abilities and now we discover that bacteria cansurvive 34,000 years in a salt bubble. It is an idea that would have been rejected out of hand had not theevidence been there.
Last year we had the impossibleTyrannosaurus Rex DNA discovery in fossilized bone however it may bedegraded. Lately we learn that we arefour years out to have a living mammoth wandering about. Of course, that may turn out to be four yearsof work chopped up into separate parts like every busy lawyer.
The idea of life forms travelingin space great distances continues to become more believable. Protection form radiation is too easy toeffect in a comet and micro environs such as this can do it.
34,000-Year-Old Organisms Found Buried Alive!
Jan 6, 2011 5:53 PM ET
By Andrea Mustain,OurAmazingPlanet Staff Writer
They're aliiiiiiiive! But difficult to spot. The bacteria are the tiny,pin-prick-looking objects, dwarfed by the larger, spherical algal cells. Thecolored spots come from pigments the algae produce, carotenoids, still vibrant30,000 years on. Credit: Brian Schubert.
It's a tale that has all the trappings of a cult 1960s sci-fi movie:Scientists bring back ancient salt crystals, dug up from deep below Death Valley for climate research. The sparkling crystalsare carefully packed away until, years later, a young, unknown researcher takesa second look at the 34,000-year-old crystals and discovers, trapped inside,something strange. Something … alive.
Thankfully this story doesn't end with the destruction of the humanrace, but with a satisfied scientist finishing his Ph.D.
"It was actually a very big surprise to me," said BrianSchubert, who discovered ancient bacteria living withintiny, fluid-filled chambers inside the salt crystals.
Saltcrystals grow very quickly, imprisoning whatever happens to befloating — or living — nearby inside tiny bubbles just a few microns across,akin to naturally made, miniature snow-globes.
"It's permanently sealed inside the salt, like little timecapsules," said Tim Lowenstein, a professor in the geology department at Binghamton University and Schubert's advisor at thetime.
Lowenstein said new research indicates this process occurs in modernsaline lakes, further backing up Schubert’s astounding discovery, which wasfirst revealed about a year ago. The new findings, along with details ofSchubert’s work, are published in the January 2011 edition of GSA Today, thepublication of the Geological Society of America .
Schubert, now an assistant researcher at the University of Hawaii, saidthe bacteria — a salt-loving sort still found on Earth today — were shrunken andsmall, and suspended in a kind of hibernation state.
"They're alive, but they're not using any energy to swim around,they're not reproducing," Schubert told OurAmazingPlanet. "They'renot doing anything at all except maintaining themselves."
The key to the microbes' millennia-long survival may be their fellowcaptives — algae, of a group called Dunaliella.
"The most exciting part to me was when we were able to identifythe Dunaliella cells in there," Schubert said, "becausethere were hints that could be a food source."
With the discovery of a potential energy source trapped alongside thebacteria, it has begun to emerge that, like an outlandish Dr. Seuss invention(hello, Who-ville), these tiny chambers could house entire, microscopicecosystems.
Other elderly bacteria?
Schubert and Lowenstein are not the first to uncover organisms thatare astonishinglylong-lived. About a decade ago, there were claims of discoveries of250-million-year-old bacteria. The results weren't reproduced, and remaincontroversial.
Schubert, however, was able to reproduce his results. Not only did hegrow the same organisms again in his own lab, he sent crystals to another lab,which then got the same results.
"So this wasn’t something that was just a contaminant from ourlab," Schubert said.
The salt crystals get their pinkish hue from the host of microorganismstrapped inside. Credit: Michael Timofeeff.
Survival strategy
The next step for researchers is to figure out how the microbes,suspended in a starvation-survival mode for so many thousands of years, managedto stay viable.
"We're not sure what's going on," Lowenstein said. "Theyneed to be able to repair DNA, because DNA degrades with time."
Schubert said the microbes took about two-and-a-half months to"wake up" out of their survival state before they started toreproduce, behavior that has been previously documented in bacteria, and astrategy that certainly makes sense.
"It's 34,000 years old and it has a kid," Schubert said. Andironically, once that happens, the new bacteria are, of course, entirelymodern.
Of the 900 crystal samples Schubert tested, only five produced livingbacteria. However, Schubert said, microbes are picky. Most organisms can't becultured in the lab, so there could be many living microbes that just didn'tlike their new home enough to reproduce.
Still, wasn't it exciting to discover what could be one of the oldestliving organisms on the planet?
"It worked out very well," Schubert said.
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