[meteorite-list] Underground Bacteria
From: drtanuki <drtanuki_at_meteoritecentral.com>
Date: Thu Oct 26 12:38:18 2006 Message-ID: <20061026163704.93025.qmail_at_web53205.mail.yahoo.com> Dear Pete, Yes, this was posted early by Ron Baalke; nevertheless it is an interesting paper for those that missed it the first time. Currently, we (The Tokyo University) are studying bacteria that I collected from two oil wells in NE Colorado. The samples came from a depth of 1456 meters below the surface. Thank you for your posting and Ron`s earlier posting. Best, Dirk Ross..Tokyo --- Pete Pete <rsvp321_at_hotmail.com> wrote: > Apologies if this was posted earlier - I may have > missed it. > > > > http://www.princeton.edu/main/news/archive/S16/13/72E53/index.xml?section=newsreleases > > Abstract > > Long-Term Sustainability of a High-Energy, > Low-Diversity Crustal Biome > > By Li-Hung Lin, Pei-Ling Wang, Douglas Rumble, > Johanna Lippmann-Pipke, Erik > Boice, Lisa M. Pratt, Barbara Sherwood Lollar, Eoin > L. Brodie, Terry C. > Hazen, Gary L. Andersen, Todd Z. DeSantis, Duane P. > Moser, Dave Kershaw, and > T. C. Onstott > > Geochemical, microbiological, and molecular analyses > of alkaline saline > groundwater at 2.8 kilometers depth in Archaean > metabasalt revealed a > microbial biome dominated by a single phylotype > affiliated with thermophilic > sulfate reducers belonging to Firmicutes. These > sulfate reducers were > sustained by geologically produced sulfate and > hydrogen at concentrations > sufficient to maintain activities for millions of > years with no apparent > reliance on photosynthetically derived substrates. > > > News Releases > All News Releases | ? Previous News Release | Next > News Release ? For > immediate release: October 20, 2006 > Media contact: Chad Boutin, (609) 258-5729, > cboutin_at_princeton.edu > Two miles underground, strange bacteria are found > thriving > A Princeton-led research group has discovered an > isolated community of > bacteria nearly two miles underground that derives > all of its energy from > the decay of radioactive rocks rather than from > sunlight. According to > members of the team, the finding suggests life might > exist in similarly > extreme conditions even on other worlds. > > The self-sustaining bacterial community, which > thrives in nutrient-rich > groundwater found near a South African gold mine, > has been isolated from the > Earth's surface for several million years. It > represents the first group of > microbes known to depend exclusively on geologically > produced hydrogen and > sulfur compounds for nourishment. The extreme > conditions under which the > bacteria live bear a resemblance to those of early > Earth, potentially > offering insights into the nature of organisms that > lived long before our > planet had an oxygen atmosphere. > > The scientists, who hail from nine collaborating > institutions, had to burrow > 2.8 kilometers beneath our world's surface to find > these unusual microbes, > leading the scientists to their speculations that > life could exist in > similar circumstances elsewhere in the solar system. > > "What really gets my juices flowing is the > possibility of life below the > surface of Mars," said Tullis Onstott, a Princeton > University professor of > geosciences and leader of the research team. "These > bacteria have been cut > off from the surface of the Earth for many millions > of years, but have > thrived in conditions most organisms would consider > to be inhospitable to > life. Could these bacterial communities sustain > themselves no matter what > happened on the surface? If so, it raises the > possibility that organisms > could survive even on planets whose surfaces have > long since become > lifeless." > > Onstott's team published its results in the Oct. 20 > issue of the journal > Science. The research group includes first author > Li-Hung Lin, who performed > many of the analyses as a doctoral student at > Princeton and then as a > postdoctoral researcher at the Carnegie Institution. > > "These bacteria are truly unique, in the purest > sense of the word," said > Lin, now at National Taiwan University. "We know how > isolated the bacteria > have been because analyses of the water that they > live in showed that it's > very old and hasn't been diluted by surface water. > In addition, we found > that the hydrocarbons in the environment did not > come from living organisms, > as is usual, and that the source of the hydrogen > needed for their > respiration comes from the decomposition of water by > radioactive decay of > uranium, thorium and potassium." > > > Because the groundwater the team sampled to find the > bacteria comes from > several different sources, it remains difficult to > determine specifically > how long the bacteria have been isolated. The team > estimates the time frame > to be somewhere between three and 25 million years, > implying that living > things are even more adaptable than once thought. > > "We know surprisingly little about the origin, > evolution and limits for life > on Earth," said biogeochemist Lisa Pratt, who led > Indiana University > Bloomington's contribution to the project. > "Scientists are just beginning to > study the diverse organisms living in the deepest > parts of the ocean, and > the rocky crust on Earth is virtually unexplored at > depths more than half a > kilometer below the surface. The organisms we > describe in this paper live in > a completely different world than the one we know at > the surface." > > That subterranean world, Onstott said, is a > lightless pool of hot, > pressurized salt water that stinks of sulfur and > noxious gases humans would > find unbreathable. But the newly discovered > bacteria, which are distantly > related to the Firmicutes division of microbes that > exist near undersea > hydrothermal vents, flourish there. > > "The radiation allows for the production of lots of > sulfur compounds that > these bacteria can use as a high-energy source of > food," Onstott said. "For > them, it's like eating potato chips." > > But the arrival of the research team brought one > substance into the > underground world that, though vital to human > survival, proved fatal to the > microbes -- air from the surface. > > "These critters seems to have a real problem with > being exposed to oxygen," > Onstott said. "We can't seem to keep them alive > after we sample them. But > because this environment is so much like the early > Earth, it gives us a > handle on what kind of creatures might have existed > before we had an oxygen > atmosphere." > > Onstott said that many hundreds of millions of years > ago, some of the first > bacteria on the planet may have thrived in similar > conditions, and that the > newly discovered microbes could shed light on > research into the origins of > life on Earth. > > "These bacteria are probably close to the base of > the tree for the bacterial > domain of life," he said. "They might be > genealogically quite ancient. To > find out, we will need to compare them to other > organisms such as Firmicutes > and other such heat-loving creatures from deep sea > vents or hot springs." > > The research team is building a small laboratory 3.8 > kilometers beneath the > surface in the Witwatersrand region of South Africa > to conduct further study > of the newly discovered ecosystem, said Onstott, who > hopes the findings will > be of use when future space probes are sent to seek > life on other planets. > > "A big question for me is, how do these creatures > sustain themselves?" > Onstott said. "Has this one strain of bacteria > evolved to possess all the > characteristics it needs to survive on its own, or > are they working with > other species of bacteria? I'm sure they will have > more surprises for us, > and they may show us one day how and where to look > for microbes elsewhere." > > Other authors of this work include Johanna > Lipmann-Pipke of > GeoForschungsZentrum, Potsdam, Germany; Erik Boice > of Indiana University; > Barbara Sherwood Lollar of the University of > Toronto; Eoin L. Brodie, Terry > C. Hazen, Gary L. Andersen and Todd Z. DeSantis of > Lawrence Berkeley > National Laboratory, Berkeley, Calif.; Duane P. > Moser of the Desert Research > Institute, Las Vegas; and Dave Kershaw of the > Mponeng Mine, Anglo Gold, > Johannesburg, South Africa. > > Pratt and Onstott have collaborated for years as > part of the > Indiana-Princeton-Tennessee Astrobiology Institute > (IPTAI), a NASA-funded > research center focused on designing instruments and > probes for life > detection in rocks and deep groundwater on Earth > during planning for > subsurface exploration of Mars. IPTAI's > recommendations to NASA will draw on > findings discussed in the Science report. > > This work was also supported by grants from the > National Science Foundation, > the U.S. Department of Energy, the National Science > Council of Taiwan, the > Natural Sciences and Engineering Research Council of > Canada, Deutsche > Forschungsgemeinschaft (DFG, German Research > Foundation) and the Killam > Fellowships Program. > > More information about the discovery can be found at > > http://newsinfo.iu.edu/news/page/normal/4229.html > and > http://www.carnegieinstitution.org/news_releases/news_2006_1019.html > > > > > http://www.princeton.edu/main/news/archive/S16/13/72E53/index.xml?section=newsreleases > > _________________________________________________________________ > Experience Live Search from your PC or mobile device > today. > http://www.live.com/?mkt=en-ca > > ______________________________________________ > Meteorite-list mailing list > Meteorite-list_at_meteoritecentral.com > http://six.pairlist.net/mailman/listinfo/meteorite-list > Received on Thu 26 Oct 2006 12:37:04 PM PDT |
StumbleUpon del.icio.us Yahoo MyWeb |