Navigation Links
Bacteria that use radiated water as food

Researchers from Indiana University Bloomington and eight collaborating institutions report in this week's Science a self-sustaining community of bacteria that live in rocks 2.8 kilometers below Earth's surface. Think that's weird? The bacteria rely on radioactive uranium to convert water molecules to useable energy.

The discovery is a confirmed expansion of Earth's biosphere, the three-dimensional shell that encompasses all planetary life.

The research has less Earthly implications, however. It will likely fuel optimism that life exists in other deep subsurface environments, such as in groundwater beneath the permafrost on Mars.

"We know surprisingly little about the origin, evolution and limits for life on Earth," said IUB biogeochemist Lisa Pratt, who led IU Bloomington's contribution to the project. "Scientists are just beginning to study the diverse organisms living in the deepest parts of the ocean. 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."

Bacteria living in groundwater or in other subsurface environments is not news. Until now, however, it was not known whether subterranean microorganisms were recent arrivals bound for extinction or whether they were permanent fixtures of an unlikely habitat. Also, many scientists have been skeptical of subsurface bacterial communities being completely disconnected from surface ecologies fed by the sun's light.

Pratt, Princeton University geomicrobiologist Tullis Onstatt and former graduate student Li-Hung Lin (the paper's lead author, now at National Taiwan University) and colleagues present evidence the bacterial communities are indeed permanent -- apparently millions of years old -- and depend not on sunlight but on radiation from uranium ores for their existence.

Coauthors of the present paper learned of a new water-filled fracture inside a South African gold mine near the Johannesburg metropolitan area and viewed it as an opportunity to study subsurface rock uncontaminated by human activities. Lin and others in the research team traveled to the mine and descended the hot, gas-choked shafts to study water slowly seeping from the crack.

The scientists sampled the flowing fracture water many times over 54 days to determine whether the community of microbes, if present, changed in composition and character, and to determine whether contamination had occurred. The researchers also examined the age of the fracture water and its chemical composition.

This fracture water contained hydrocarbons and hydrogen not likely to have been created through biological processes, but rather from decomposition of water exposed to radiation from uranium-bearing rocks.

High density DNA microarray analysis revealed a vast number of bacterial species present, but the samples were dominated by a single new species related to hydrothermal vent bacteria from the division Firmicutes. The ancient age of the fracture water and comparative DNA analysis of the bacterial genes suggests subsurface Firmicutes were removed from contact with their surface cousins anywhere from 3 million to 25 million years ago. The bacteria's rocky living space is a metamorphosed basalt that is about 2.7 billion years old. How surface-related Firmicutes and other species managed to colonize an area so deep within Earth's crust is a mystery.

Some surface Firmicutes species are known to consume sulfate and hydrogen as a way to get energy for growth. Other bacteria can then use the by-products of the Firmicutes as a source of food. The scientists found that the fracture Firmicutes are also able to consume sulfate. Firmicutes do not use radiation directly as a source of energy, however.

Radiation emanating from uranium minerals in or near the fracture allows for the fo rmation of hydrogen gas from decomposition of water and formation of sulfate from decomposition of sulfur minerals. Hydrogen gas is highly energetic if it reacts with oxygen or other oxidants like sulfate, as the Hindenburg disaster demonstrated. Firmicutes are able to harvest energy from the reaction of hydrogen and sulfate, allowing other microbes in the fracture community to use the chemical waste from the Firmicutes as food.

In a way, Firmicutes serve the same function as photosynthetic organisms, such as plankton and trees at Earth's surface, that capture sunlight energy ultimately to the benefit of everything and everyone else. In the deep subsurface case, Firmicutes species are the producers, capturing the energy of radiation-borne hydrogen gas to support microbial communities.


'"/>

Source:Indiana University


Related biology news :

1. Bacteria collection sheds light on urinary tract infections
2. Solution to Pollution: New Bacteria Eats Toxic Waste
3. The Bacterias guide to survival
4. UF Researchers Map Bacterial Proteins That Cause Tooth Loss
5. Bacterial genome sheds light on synthesizing cancer-fighting compounds
6. Where Bacteria Get Their Genes
7. Bacteria feed on smelly breath (and feet)
8. New insight into autoimmune disease: Bacterial infections promote recognition of self-glycolipids
9. Bacteria use hosts immune response to their competitive advantage
10. Say what? Bacterial conversation stoppers
11. Bacteria are key to green plastics, drugs
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:4/11/2017)... April 11, 2017 NXT-ID, Inc. (NASDAQ: ... company, announces the appointment of independent Directors Mr. Robin ... its Board of Directors, furthering the company,s corporate governance and ... Gino Pereira ... look forward to their guidance and benefiting from their considerable ...
(Date:4/4/2017)... NEW YORK , April 4, 2017   ... solutions, today announced that the United States Patent and ... The patent broadly covers the linking of an iris ... the same transaction) and represents the company,s 45 th ... our latest patent is very timely given the multi-modal ...
(Date:3/29/2017)... the health IT company that operates the largest health ... today announced a Series B investment from BlueCross BlueShield ... investment and acquisition accelerates higi,s strategy to create the ... activities through the collection and workflow integration of ambient ... secures data today on behalf of over 36 million ...
Breaking Biology News(10 mins):
(Date:5/22/2017)... Pittsburgh, PA (PRWEB) , ... May 22, 2017 ... ... Inc. announced today that it is exhibiting in booth B2 at the Association ... in Pittsburgh, May 22-25. , In addition to demonstrating its Cancer Diagnostic ...
(Date:5/21/2017)... CA (PRWEB) , ... May 20, 2017 , ... ... tool that helps avoid the lengthy trial and error process by finding the ... It can also strengthen the doctor-patient relationship through a personalized approach to ...
(Date:5/19/2017)... ... May 19, 2017 , ... The University City Science Center ... ripe for commercialization, and who are affiliated with the 21 partner academic and ... QED, now in its tenth round, is the first multi-institutional proof-of-concept program for ...
(Date:5/18/2017)... , ... May 18, 2017 , ... ... The Tapas Cooking Challenge is a two-hour team-building package designed for groups ... created by Chef Jodi Abel, which include items, such as Blackened Shrimp with ...
Breaking Biology Technology: