Bacteria that eat rock and need no oxygen

[masonswanson]

hey i was watching tv the other day and saw something about this but had to leave half way through it so if you know anything about these little guys then would you please tell me something?

[lindagarrette]

You must be referreing to the microbes living in the tiniest of gaps in deep granitic and basaltic formations. They metabolize hydrogen. Here is a reference site with a lot of other good stuff, too.:cup: .http://www.resa.net/nasa/otherextreme.htm

[C1ay]

hey i was watching tv the other day and saw something about this but had to leave half way through it so if you know anything about these little guys then would you please tell me something?

 

These sound like the kind of organisms that could bring life to one planet from another by surviving the rigors of intergalatic travel. Is this how life began on Earth?

[dagaz]

These sound like the kind of organisms that could bring life to one planet from another by surviving the rigors of intergalatic travel. Is this how life began on Earth?

 

This is one of two main theories as to how life began, the life-from-space theory as originally put forward by Fred Hoyle and Chandra Wickramasinghe. Many of the tenets of the theory, as it was originally put forward, have now been discredited.

 

The second theory, the chemosynthetic origins of life theory, was given strong impetus by the experiments of Urey and Miller in the 1950's which used conditions similar to those thought to be prevailing on the prebiotic Earth to produce amino acids and other organic molecules.

[alxian]

i'd asked some high energy astronomers about this type of life form and they said that the extrasolar planets we're finding may already be dead, but these creatures are hardy enough and well sheltered enough that as long as enough gases and solvent pass through their habitat that they could survive for quite a while longer than life on the surface

 

i was speculating that even if the core stopped spinning and the mantle cooled you'd still have energy potential in the form of radioactive deposits.. i passed this by michael and he said its possible but these would be the most extreme of extremophiles given the toxicity of radioactive isotopes. i'm thinking if life had enough time to evolve and had few sources of energy left it might be possible for bacteria (or possibly larger organisms) to absorb the isotopes and metabolize them, the energy potential would be massive if they could convert it naturally (nature nuclear fission) in a sped up decay process.. it would require energy storage methods exceeding what known life is capable of and a hardy dna structure not to mention high radiation tolerances.

 

imagine a planet swiss cheesed with bacterial columns originating from a uranium deposit, life funneling and recycling nuclear energy naturally. very unlikely but good for fiction :(

[TeleMad]

This is one of two main theories as to how life began, the life-from-space theory as originally put forward by Fred Hoyle and Chandra Wickramasinghe.

 

The life-from-space theory is called panspermia, and dates back to the 19th century (long time before Hoyle). Svante Arrhenius is one of the scientists who proposed it.

[Turtle]

___Rock eating bacteris I understand is now thought largely responsible for cave formation, as opposed to the leaching acid rain/water hypothesis. I think I heard they excrete sulfuric acid?

[alxian]

yes they do, meaning that sulphure sucking bacteria and their buddies down in the ocean depths can exist in very toxic environments, life can control almost all compounds in nature.. i'm wondering if their could be a super creature capable of tackling all known toxins and if their are any trully toxic compounds no life form can actually deal with.

[bumab]

i'm wondering if their could be a super creature capable of tackling all known toxins and if their are any trully toxic compounds no life form can actually deal with.

 

i've thought about that too... i'd have to say a very high radiative level would probably knock out most things, through sheer damage to DNA. there'd have to be incredible DNA repairing protiens just to deal with the little amounts of radiation cockroaches have withstood. anything much higher, and i think most life would be toast...

[Fishteacher73]

There are actually bacteria found living in barrels of radio-active wastes, others that use plutnium and other radio-active elements.

 

It is theorized that the bacteria in the sub-soil actually out number (in both numbers and bio-mass) that life at the surface. One estimate would cover the surface of the Earth to a depth of about 5 feet of single celled organisms...

[Fishteacher73]

i'm wondering if their could be a super creature capable of tackling all known toxins and if their are any trully toxic compounds no life form can actually deal with.

 

While it is amazing at the diversity of bacteria and where they can thrive (On a return Apollo mission they found a strain of staph. that had continued to live in camera left ion the moon for two years). So we are continually having to edge back what we think the boundries of life are, and it the bacteria that are leading the way.

 

As for toxic compounds...IMO there probably are some man-made compounds that are pretty much universally toxic to all life (maybe given time some will be immune or even thrive with it). So I did some digging...The Merk Index lists a family of seven different proteins produced by the Clostridium botulinum bacterium, these are the ones that cause botulism. These seven toxins have a median lethal dose in mice of 0.0000003 mg of botulin/kg of body mass in mice.

This is the smallest LD50 listed. (For comparison Ricin has a LD50 of 0.001 mg of ricin/kg of body mass)

But surprisingly thse compounds are organic in nature and NOT mand-made....So much for that initial idea.... :o

The most toxic man-made are the dioxin family, but they have a LD50 of 0.045 mg of dioxin/kg of body mass for rats. (over 100,000 times that of the botulism toxin).

[alxian]

so then maybe a uranium munching bacteria isn't so far fetched after all hmm? excellent

[Fishteacher73]

so then maybe a uranium munching bacteria isn't so far fetched after all hmm? excellent

 

Not far fetched, but likely....

[TeleMad]

... (On a return Apollo mission they found a strain of staph. that had continued to live in camera left ion the moon for two years).

 

Actually, it was a streptococcus.

 

“At the other extreme, viable specimens of the bacterium Streptococcus mitis were retrieved from the surface of the Moon, where they endured a complete vacuum for two years while attached to a camera housing on the Surveyor III spacecraft.” (The Fifth Miracle: The Search for the Origin and Meaning of Life, Paul Davies, Simon & Shuster, 1999, p 165)

 

“Streptococcus mitis survived 31 months in the space environment in a contaminated Surveyor spacecraft on the surface of the moon(10)” (Evolution on planet Earth: origins and achievements, David D. Wynn-Williams, Trends in Ecology & Evolution, 1999, 14:10:379-381: the (10) reference, listed at the end of the article, is: (10) Apollo Program Summary Report (1975) Section 3.2.28 Surveyor III Analysis, in vol. JCS-09423, NASA, Houston”.

[TeleMad]

alxian: i'm wondering if their could be a super creature capable of tackling all known toxins and if their are any trully toxic compounds no life form can actually deal with.

 

Someone suggested radiation, but first, it's not a compound, and second, as Fishteacher73 pointed out, some bacteria thrive in radiation.

 

You do raise an interesting question. For example, cyanide (CN-) is a poison because it binds to the final cytochrome of the electron transport chain, stopping the flow of electrons and thus the production of ATP. Yet cyanide is considered to have been prevalent during the origin of life (and many organic compounds are thought to have been formed by the repeated combining of hydrogen cynaide (HCN) molecules).

 

Since life can probably survive without proteins, but not without nucleic acids, and could possibly be as simple as a self-replicating RNA, the universal toxin would need to destroy nucleic acids somehow. Maybe it's just some concentrated strong acid, like H2SO4, HNO3, HCLO4, HCL, HBr, or HI.

 

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PS: Forgot for a moment that there are bacteria that live in highly acidic solutions. So that kills my latter idea of H2SO4 or some other strong acid being a universal poison.

 

Apparently, the strong acid does not make it all the way to the DNA because I believe if it did it would destroy the DNA. I'm guessing that the flow of protons into the bacterium is used to make ATP by chemiosmosis (which I know occurs in many bacteria) at the periphery of the cell, with the protons then being pumped back out of the cell in the process: if the inside became more acidic than the outside, chemiosmosis would stop - so the bacteria would need to maintain the inside at a higher pH than the outside and the continuous pumping of protons out of the cell would prevent the strong acid from destroying the DNA.