Atomic Powered Bacteria discovered

Majin Gojira · Post by **Majin Gojira** » 2006-10-20 10:00am

Gold mine holds life untouched by the Sun
19:00 19 October 2006
NewScientist.com news service
Debora MacKenzie

The bacteria exist without the option of photosynthesis by using radioactive uranium to convert water molecules to useable energy. Similar life forms may exist on other planets, experts speculate.

The bacteria live in ancient water trapped in a crack in basalt rock, 3 to 4 kilometres down. Scientists from Princeton University in New Jersey, US, and colleagues analysed water from the fissure after it was penetrated by a narrow exploratory shaft in the Mponeng gold mine near Johannesburg, South Africa. The shaft was then closed.

There were many species of bacteria present, but RNA sequencing showed most were a previously-unknown type of bacteria dubbed Desulfotomaculum.

“Similar microbes have been detected in many subsurface environments,” study leader Li-Hung Lin, now at National Taiwan University, told New Scientist. “What is unique in our study is that this microbial community doesn’t depend on photosynthetic products.”

Alternative power
All living things require a source of energy – which is directly or indirectly from the Sun. Green plants use the Sun’s energy, in a process called photosynthesis, to make energy-rich chemical bonds, for example, between the carbon and hydrogen atoms in sugar molecules. Some of the energy stored in these bonds is then released when a living organism replaces the hydrogen with oxygen, giving off CO2.

Without the solar energy that plants harness to make those hydrogen-carbon bonds, none of this is possible. But the Mponeng bacteria have another source of energy.

“Sulphate and hydrogen gas are generated from geological processes. Microbes use these nutrients to live,” explains Lin.

Energy of radiation
Uranium and other radioactive elements in the rock emit radiation that shatters water molecules, producing high-energy hydrogen gas that is able to cleave chemical bonds.

The bacteria exploit this hydrogen gas to turn sulphate (SO4) molecules from the rock into hydrogen sulphide (HS). It is the energy-trapping equivalent of photosynthesis. The energy of radiation, which makes hydrogen gas energetic enough to form these bonds, replaces the energy of the Sun.

The team examined the sulphur atoms in the hydrogen sulphide they found. The ratio of isotopes – different chemical forms of the same element – proved the sulphide was produced by living organisms, in a similar way that carbon dating can be used to show whether carbon compounds have been produced by living or non-living processes.

Dying or flourishing
Other sulphate-eating bacteria have been found in ocean sediments, volcanoes and oil deposits. But all have either received some chemicals produced by photosynthesis, or it has not been clear whether they were trapped and dying, or flourishing.

A study of the inert gases in the sample, such as xenon, show that the Mponeng water has been isolated from the surface for 20 million years, says Lin. This shows that the bacteria must live totally “independent from surface photosynthesis”.

It is not known how widespread these communities are on Earth, he says. But the discovery of a stable, light-independent life form raises hopes of finding similar creatures on other planets.

Research team-member Lisa Pratt at Indiana University at Bloomington, US, also heads a team funded by NASA to design probes to look for just such life under the permafrost of Mars.

Sorry if someone beat me to it.

Gil Hamilton · Post by **Gil Hamilton** » 2006-10-20 10:39am

Technically, the bacteria isn't nuclear powered, since it is doing a pretty standard chemoautotrophic process for power (using available hydrogen gas to turn sulfates into hydrogen sulfide), rather than using the radiation directly as part of a biological process (which does occur, in photosynthesis, so technically, any photosynthetic lifeform that gets energy from the sun has a nuclear battery).

However, that is a really cool bacteria they've found because it does have the implications mentioned in the article, that life isn't sun dependant so you could have life outside the solar "temperate" zone. I bet that you could get bacteria living in Europa that gets the base energy in its environment from tidal effects from Jupiter. Radioactivity could do it in other places.

To quote a terrible character from Jurassic Park "Life finds a way".

SirNitram · Post by **SirNitram** » 2006-10-20 01:20pm

The Rules.
...
6. Life Turns Up Everywhere It Can.
7. Life Turns Up Everywhere It Can't.
...

Amazing. Just mind-blowing.

Count Dooku · Post by **Count Dooku** » 2006-10-20 01:33pm

That is one of the coolest things I've ever read.

Feil · Post by **Feil** » 2006-10-20 02:14pm

Awesome.

Would this work in eukaryotic cells?

Admiral Valdemar · Post by **Admiral Valdemar** » 2006-10-20 03:32pm

Feil wrote:Awesome.

Would this work in eukaryotic cells?

That depends on just what biochemistry is being used here. Prokaryotes are the most diverse form of life around and they adapt to new situations quicker than any other organism. It's very rare to find more advanced cell types doing what bacteria can do, simply because the simpler, hardier bacterial cell is better able to conquer all environments.

SeeingRed · Post by **SeeingRed** » 2006-10-20 05:20pm

What are the yields on something like this? Would it be possible to use these things in some sort of bio-power plant?

Admiral Valdemar · Post by **Admiral Valdemar** » 2006-10-20 06:06pm

Uh, no. No more than any other form of bacteria.

Winston Blake · Post by **Winston Blake** » 2006-10-20 09:27pm

Gil Hamilton wrote:However, that is a really cool bacteria they've found because it does have the implications mentioned in the article, that life isn't sun dependant so you could have life outside the solar "temperate" zone. I bet that you could get bacteria living in Europa that gets the base energy in its environment from tidal effects from Jupiter. Radioactivity could do it in other places.

Does anyone know if it's impossible for such 'non-temperate' life to develop into higher animals, possibly intelligent life? It's just that all these awesome bacteria seem to live in water, and underwater life could never smelt metals etc.

Drooling Iguana · Post by **Drooling Iguana** » 2006-10-20 11:00pm

So, if one of these bacteria bit a nerdy teenager, would he end up with the proportional strength and speed of a bacterium?

Gil Hamilton · Post by **Gil Hamilton** » 2006-10-20 11:23pm

Winston Blake wrote:Does anyone know if it's impossible for such 'non-temperate' life to develop into higher animals, possibly intelligent life? It's just that all these awesome bacteria seem to live in water, and underwater life could never smelt metals etc.

I don't know. Bacteria is so adaptable because it's very very simple. It's easy for it to deal with stuff because it replicates like crazy and mutates easily. Multicellular life of any sort can do alot more tricks, but it's not very adaptable. Of course, I could be completely wrong in what's out there.

If it could evolve into something complex, I'm thinking it would be something colonial with specialized members. You might say, isn't that a multicellular lifeform, hur hur hur, but I'm thinking something a little more loose. Maybe not to the point of organs, but something like archaea that arranges itself like building blocks and how each archaea arranges itself in relationship with its mates, the different tasks it can do. From that, you might find something patently amazing.

Sikon · Post by **Sikon** » 2006-10-20 11:32pm

SeeingRed wrote:What are the yields on something like this? Would it be possible to use these things in some sort of bio-power plant?

I forget exactly: Either 1 gram of hydrogen bacteria can be grown per 0.5 grams of hydrogen, or it is the other way around.

The bacteria are not an energy source. Any use of them would give less energy than the original hydrogen they consumed: far inferior to regular geothermal power.

But they might be used as very compact source of biomass (i.e. fish-food) in a closed life support system. For example, a 1MW miniature low-power nuclear reactor the size of a room or smaller could make at least 300,000lb of hydrogen annually.

Rekkon · Post by **Rekkon** » 2006-10-21 02:52pm

Gil Hamilton wrote:
Winston Blake wrote:Does anyone know if it's impossible for such 'non-temperate' life to develop into higher animals, possibly intelligent life? It's just that all these awesome bacteria seem to live in water, and underwater life could never smelt metals etc.
I don't know. Bacteria is so adaptable because it's very very simple. It's easy for it to deal with stuff because it replicates like crazy and mutates easily. Multicellular life of any sort can do alot more tricks, but it's not very adaptable. Of course, I could be completely wrong in what's out there.

If it could evolve into something complex, I'm thinking it would be something colonial with specialized members. You might say, isn't that a multicellular lifeform, hur hur hur, but I'm thinking something a little more loose. Maybe not to the point of organs, but something like archaea that arranges itself like building blocks and how each archaea arranges itself in relationship with its mates, the different tasks it can do. From that, you might find something patently amazing.

I read somewhere that they already have found bacterial colonies something like that. The outer ones multiply more quickly to extend their search for 'food,' while the inner once do little replication and are passed nutrients from the ones on the edge. I forget how the inner onces contributed to the colony as a whole, but it was interesting to see that colony was not an 'every bacterium for itself' setup. I think it was in Science News, but their site is frakking slow, and I do not feel like wading through 58 pages of results because their search feature sucks.

Gil Hamilton · Post by **Gil Hamilton** » 2006-10-21 03:20pm

Rekkon wrote:I read somewhere that they already have found bacterial colonies something like that. The outer ones multiply more quickly to extend their search for 'food,' while the inner once do little replication and are passed nutrients from the ones on the edge. I forget how the inner onces contributed to the colony as a whole, but it was interesting to see that colony was not an 'every bacterium for itself' setup. I think it was in Science News, but their site is frakking slow, and I do not feel like wading through 58 pages of results because their search feature sucks.

That's the sort of thing I'm getting at, but evolving into something more complex to the point of amazing.

Max · Post by **Max** » 2006-11-03 11:22am

Very cool.. I printed it and am bringing it into my bio professor

SyntaxVorlon · Post by **SyntaxVorlon** » 2006-11-04 12:52pm

Admiral Valdemar wrote:
Feil wrote:Awesome.

Would this work in eukaryotic cells?
That depends on just what biochemistry is being used here. Prokaryotes are the most diverse form of life around and they adapt to new situations quicker than any other organism. It's very rare to find more advanced cell types doing what bacteria can do, simply because the simpler, hardier bacterial cell is better able to conquer all environments.

In this case, the simpler DNA is shorter and thus less likely to be pulverized by ionizing radiation. Lifeforms with a more complex DNA molecule would be subject to dangerous changes eg cancer.

drachefly · Post by **drachefly** » 2006-11-05 08:56am

It isn't that the DNA is shorter, it's that individuals are largely disposable. If one gets nailed by radiation, it just dies and its neighbors eat it.