The world's oldest bacteria.

[arkady]

Wasn't sure were to put this really, as it isn't really spacescience, but as the article mentions it is quite interesting with respect to Martian conditions. Anyways, here goes .. <br /><br />From ScienceDaily.<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p>A research team has for the first time ever discovered DNA from living bacteria that are more than half a million years old. Never before has traces of still living organisms that old been found. <br /><br />The exceptional discovery can lead to a better understanding of the aging of cells and might even cast light on the question of life on Mars. The discovery was made by Professor Eske Willerslev from the University of Copenhagen and his international research team. <br /><br />All cells decompose with time. But some cells are better than others to postpone the decomposing and thus delay aging and eventually death. And there are even organisms that are capable of regenerate and thereby repair damaged cells. These cells -- their DNA -- are very interesting to the understanding of the process of how cells break down and age. <br /><br />The research team, which consists of experts in, among other things, DNA traces in sediments and organisms, have found ancient bacteria that still contains active and living DNA. So far, it is the oldest finding of organisms containing active DNA and thus life on this earth. The discovery was made after excavations of layers of permafrost in the north-western Canada, the north-eastern Siberia and Antarctica. <br /><br />The project is about examining how bacteria can live after having been frozen down for millions of years. Other researchers has tried to uncover the life of the past and the following evolutionary development by focusing on cells that are in a state of dead-like lethargy. "We, on the other hand, have found a method that makes is possible to extract and isolate DNA t</p></blockquote> <div class="Discussion_UserSignature"> "<font color="#0000ff"><em>The choice is the Universe, or nothing</em> ... </font>" - H.G Wells </div>

 

[silylene old]

There is a BIG difference between a couple of million years on Earth and a couple of <i>billion</i> years (3 orders of magnitude!) on Mars. Putative Martian life remnants from its ancient aquatic times would also need to survive:<br />- billions of years of ultraviolet light (no ozone layer)<br />- billions of years of high energy radiation (cosmic rays, etc) (no magnetic field)<br />- billions of years of alpha and gamma irradiation from trace radioactives in the minerals and soils<br />- billions of years of peroxides in the soils and dusts<br />- billions of years of highly acidic soils (in some locations)<br />- billions of years of meteoric bombardment<br />- widely varying climates as orbital tilt repeatedly changed from 0 to 40 degrees, which evaporated and redeposited 'permanent' ices into new locations.<br /><br />Life on Earth sure had an easier time, and it was only 1/1000 as long. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[h2ouniverse]

True for the first meter of martian soil.<br />Less true below, especially at say 2 to 10 kms in depth where warm conditions should be little affected by the surface conditions.<br /><br />I think however that such self-repair features à la Deinococcus Radiodurans will prove very helpful for ourselves. One day.

 

[arkady]

Yes, I'm aware if the differences, and that there's not necessarily an immediate connection between this research and what's happening on Mars. However, if you'd be planning a research sortie up there, I'd be inclined to go have a chat with these fellas. Surely the technigues (sp?) used to produce these results would be similar on Mars. <div class="Discussion_UserSignature"> "<font color="#0000ff"><em>The choice is the Universe, or nothing</em> ... </font>" - H.G Wells </div>

 

[silylene old]

The second meter is the same as first meter given erosion and meteoric churn over 2-3 billion years. This is true until you get to perhaps the 20'th meter deep.<br /><br />Regardless, at 20m or 2km deep you still have to contend with 2-3 billion years of slow but continual irradiation from alpha particles and gamma rays from trace radioactives in the minerals and soils.<br /><br />I seriously doubt that even the hardiest viral spore can survive this. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[brellis]

hey silylene<br /><font color="yellow">Life on Earth sure had an easier time, and it was only 1/1000 as long.</font><br /><br />The time scale is dramatic. I read somewhere that bacteria can live 15-20 million yrs. If subsurface temp's didn't decline as quickly, perhaps some little beloved immortals have survived? <div class="Discussion_UserSignature"> <p><font size="2" color="#ff0000"><em><strong>I'm a recovering optimist - things could be better.</strong></em></font> </p> </div>

 

[3488]

How's this????<br /><br />Bacteria revived after 250 Million Years.<br /><br />Ancient evaporated sea in New Mexico, USA.<br /><br />Very, very interesting stuff.<br /><br />Below: By drilling a channel (arrow) into pockets of ancient seawater trapped in salt crystals<br />such as this one, scientists found bacteria that may be 250 million years old. <br />(Photo: Rosenzweig and Vreeland).<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[docm]

<font color="yellow">Regardless, at 20m or 2km deep you still have to contend with 2-3 billion years of slow but continual irradiation from alpha particles and gamma rays from trace radioactives in the minerals and soils. </font><br /><br />Life is tougher than most think. <br /><br />There are extremophile bacteria that live at the depth of S. Africa's gold mines that use radioactive materials by-products as their energy source, much like the bugs @ black smokers on the sea floor.<br /><br />There are also radioresistant extremophile bacteria of which deinococcus radiodurans, AKA "Conan the Bacterium", is the best example. It can survive both UV and ionizing radiation.<br /><br />The radiation unit is the Gy (Gray). <br />1 Gy = 100 Rads.<br /><br />a daily dose of 1.8-2.0 Gy is often used in radiotherapy, up to a total of 40-80 Gy.<br />a single dose of 10 Gy will kill humans. <br />a single dose of 60-65 Gy will zero out an e. coli culture.<br />a single dose of 5,000 Gy will have <font color="yellow"><b>no effect</b></font>/b> on a d. radiodurans culture.<br />a single dose of 15,000 Gy will still leave 1/3 of d. radiodurans still chugging along.<br /><br />It can also survive heat, cold, dehydration, vacuum, <i>and</i> acids.<br /><br />A GM strain has been produced that can detoxify both mercury and toluene mixed into radioactive wastes.<br /><br />Tough little SOB <img src="/images/icons/tongue.gif" /><br /><br />D. radiodurans has multiple copies of its genome arranged in toroids and very rapid repair mechanisms. <br /><br />Some bugs have crystals of manganese in their nuclei which shield their genome. <div class="Discussion_UserSignature"> </div>

 

[brellis]

I bet those little tykes will survive the subprime lending crisis as well <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <p><font size="2" color="#ff0000"><em><strong>I'm a recovering optimist - things could be better.</strong></em></font> </p> </div>

 

[heyscottie]

But only if the Fed steps in, right? <img src="/images/icons/wink.gif" />

 

[docm]

D. radiodurans will probably out-survive cockroaches <img src="/images/icons/tongue.gif" /> <div class="Discussion_UserSignature"> </div>

 

[brellis]

<img src="/images/icons/laugh.gif" /> those <i>cucaraches Federales</i> are into self-preservation, and they're pretty scummy in their own right. <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <p><font size="2" color="#ff0000"><em><strong>I'm a recovering optimist - things could be better.</strong></em></font> </p> </div>

 

[h2ouniverse]

In reply to "at 20m or 2km deep you still have to contend with 2-3 billion years of slow but continual irradiation from alpha particles and gamma rays from trace radioactives in the minerals and soils"<br />----------------<br />Silylene,<br />I think you are assuming just survival there in spore mode. But deep below, temperature is high enough to keep water liquid. If the bacteria are fully living, reproducing at high rate. Like those in deep veins on Earth, they should be subject to classical evolutionary process for correction of damage. The radiation damage you describe should not be worse than on Earth.<br />After all, Earth is far richer in radioactive elements than Mars.<br /><br />We also hope the ice shelf of Europa is enough to protect potential life in the Ocean. And at Europa surface the radiation level is far larger.<br /><br />Best regards

 

[silylene old]

I agree with you. I was discussing dormant viral-like spores, not living, reproducing bacteria, since the subject was how long a virus or bacteria could survive. I hope that was clear. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[h2ouniverse]

Sorry if I deviated the debate.<br /><br />Andrew told me you are deeply interested in KB. What's your opinion about presence of liquid water and bacterial life on some TNOs?

 

[silylene old]

I am very doubtful there is life on TNO's. <br /><br />I think it is unlikely there is liquid water on TNO's, except perhaps if one has been heated up by a recent collision. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[h2ouniverse]

To Silylene: Even on 2003EL61? <br />I am still skeptical about attempts to explain fresh cristalline ice on surface systematically by non-watery mechanisms (*) . And there quite some big ones with cristalline ice on surface. I have still not seen thermal models of TNOs. I've seen ones for smaller Ceres, that predict potential liquid phase in-depth. I cannot see why that would not apply to TNOs, especially the big differentiated ones like EL61, Eris... I am eager to see whether 4 billion years can be enough to dissipate the energy stored during the collision that shaped EL61. Even a moderate residual flux hundredths of W/m2 would keep a liquid layer.<br /><br />Best regards.<br /><br />(*) we reached paroxysm of this neo-ptolemaic trend recently about Enceladus with the magical clathrates hypothesis. And yet it's just a 500km moon!

 

[silylene old]

Well I said "unlikely". I didn't say impossible or highly unlikely. But I don't want to discourage you from considering that maybe there are ice geysers or something like this on TNO's. (And if you check back in old threads, well before the water geysers on Enceladus were discovered, I was the first person to claim that the tiger stripes were warm, and that it was even likely that the fissures themselves were at liquid water temperatures. I based on my interpretation of the first published initial infrared temperature map studies. Not a lot of people were in agreement with my guess at the time either!)<br /><br />As Niels Bohr once said, "I think that your theory is crazy. Sadly, it's not crazy enough to be believed." <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[h2ouniverse]

Sorry. I'm too recent on SDC. <br /><br />Do you know of thermal modelling of some TNOs?