NASA Sets News Conference on Astrobiology Discovery

[makc]

NASA will hold a news conference at 2 p.m. EST on Thursday, Dec. 2, to discuss an astrobiology finding that will impact the search for evidence of extraterrestrial life.

(source)

Does anyone have any idea?

[bystander]

I saw this yesterday, and still don't have a clue.

After being criticized for their handling of the Sasselov/Kepler fiasco and having been accused of holding stealth news conferences, it seems NASA has turned a new leaf. They now announce some big news, don't tell you what it is, and tell you to stay tuned for details. This is the third announcement of this type I've noticed this month. The first two involved discoveries by Chandra and EPOXI, I think. I will have to go back and look.

http://www.nasa.gov/home/hqnews/2010/no ... pdate.html
http://www.nasa.gov/home/hqnews/2010/no ... ANDRA.html

http://www.nasa.gov/home/hqnews/2010/no ... pdate.html
http://www.nasa.gov/home/hqnews/2010/no ... sults.html

[bystander]

Calm Down: NASA Hasn’t Found any Aliens
Universe Today | Astrobiology | 30 Nov 2010

You may have heard in your wanderings through the blogosphere and in the internet today that NASA will be holding a press conference on December 2nd in which they will make an announcement regarding information the search for extraterrestrial life. And that this announcement involves astrobiology, the study of life outside what we know about here on Earth. While true, it is nothing to get worked up about.

Speculation abounds that this is, “the big one,” and that an announcement will be made that extraterrestrial life has been discovered. You can find this speculation at Kottke.org, io9, Gawker, and a lot of other places.

To be clear, there is almost no chance that the press release will be announcing little green men or little brown bacteria anywhere. Follow along for the long explanation below the fold.

Here’s what the press release is titled: “NASA Sets News Conference on Astrobiology Discovery: Science Journal Has Embargoed Details Until 2 p.m. EST On Dec. 2″

Snowballing speculation over a NASA press conference
Discover Blogs | Bad Astronomy | 30 Nov 2010

Well, here we go again.

I don’t generally like to talk about NASA press conferences before they happen because I don’t want to promote baseless rumor-mongering. In this case, though, I feel I have to write something to prevent speculation! Here’s the scoop: NASA released the news that a press conference will be held on Thursday at 14:00 ET, saying that the conference will "discuss an astrobiology finding that will impact the search for evidence of extraterrestrial life."

That, of course, set everyone speculating. The very popular news site Kottke.org actually has a decent line of evidence on the topic of the conference, though a sensational headline of "Has NASA discovered extraterrestrial life?" Gawker has a post up about this as well, and social networks like reddit have a lot of people talking, too. Other examples abound.

So what’s the press conference about? I don’t know, to be honest, beyond what’s in the announcement. The scientists on the panel are interesting, including noted astrobiologists and geologists who work on solar system objects like Mars and Titan. So this is most likely going to be something about conditions on another moon or planet conducive for life.

[mak.c]

well, are they done yet?

At their conference today, NASA scientist Felisa Wolfe Simon will announce that they have found a bacteria whose DNA is completely alien to what we know today. Instead of using phosphorus, the bacteria uses arsenic.

(source)

[bystander]

Another hour before conference. Still nothing official.

Bacteria first species observed to use arsenic-laced DNA backbone
ars technica | 02 Dec 2010

All living organisms on this planet use six elements for almost all of the chemical structures of DNA, RNA, proteins, and lipids. There is a smattering of other elements, mostly metals, that are essential for biological functions (e.g., the iron in hemoglobin). However, we wouldn’t expect to find anything outside of carbon, hydrogen, oxygen, nitrogen, sulfur and phosphorus in the basic structures of biomolecules. Surprisingly, a team of scientists provide evidence in Science that another element, arsenic, can be incorporated into the basic chemical makeup of the macromolecules of life, replacing some of its phosphorus.

[neufer]

Felisa Wolfe Simon (& sister) announces her discovery

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DNA's phosphate-deoxyribose backbone

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well, are they done yet?

At their conference today, NASA scientist Felisa Wolfe Simon will announce that they have found a bacteria whose DNA is completely alien to what we know today. Instead of using phosphorus, the bacteria uses arsenic.

(source)

<<Some species of bacteria obtain their energy by oxidizing various fuels while reducing arsenates to form arsenites. In 2008, bacteria were discovered that employ a version of photosynthesis with arsenites as electron donors, producing arsenates (just like ordinary photosynthesis uses water as electron donor, producing molecular oxygen). The researchers conjectured that historically these photosynthesizing organisms produced the arsenates that allowed the arsenate-reducing bacteria to thrive.

In humans, arsenite inhibits pyruvate dehydrogenase (PDH complex) in the pyruvate acetyl CoA reaction, and binds to the SH group of lipoamide, a participant coenzyme. In this inhibition, arsenite poisoning affects energy production in the body.>>

<<A base linked to a sugar is called a nucleoside and a base linked to a sugar and one or more phosphate groups is called a nucleotide. If multiple nucleotides are linked together, as in DNA, this polymer is called a polynucleotide. The backbone of the DNA strand is made from alternating phosphate and sugar residues. The sugar in DNA is 2-deoxyribose, which is a pentose (five-carbon) sugar. The sugars are joined together by phosphate groups that form phosphodiester bonds between the third and fifth carbon atoms of adjacent sugar rings. These asymmetric bonds mean a strand of DNA has a direction. In a double helix the direction of the nucleotides in one strand is opposite to their direction in the other strand: the strands are antiparallel. The asymmetric ends of DNA strands are called the 5′ (five prime) and 3′ (three prime) ends, with the 5' end having a terminal phosphate group and the 3' end a terminal hydroxyl group. One major difference between DNA and RNA is the sugar, with the 2-deoxyribose in DNA being replaced by the alternative pentose sugar ribose in RNA.>>

[bystander]

It's official

NASA-Funded Research Discovers Life Built With Toxic Chemical
NASA Breaking News | 02 Dec 2010

NASA-funded astrobiology research has changed the fundamental knowledge about what comprises all known life on Earth.

Researchers conducting tests in the harsh environment of Mono Lake in California have discovered the first known microorganism on Earth able to thrive and reproduce using the toxic chemical arsenic. The microorganism substitutes arsenic for phosphorus in its cell components.

Thriving on Arsenic
NASA Astrobiology Magazine | 02 Dec 2010

Geomicrobiologist Felisa Wolfe-Simon has discovered a bacterium that appears able to use arsenic instead of phosphorus in its DNA. The definition of life on Earth may need to be rewritten.

Discovery of "Arsenic-bug" Expands Definition of Life
NASA Science News | 02 Dec 2010

NASA-supported researchers have discovered the first known microorganism on Earth able to thrive and reproduce using the toxic chemical arsenic. The microorganism, which lives in California's Mono Lake, substitutes arsenic for phosphorus in the backbone of its DNA and other cellular components.

A Bacterium That Can Grow by Using Arsenic Instead of Phosphorus - F Wolfe-Simon et al

• Science Express (online 02 Dec 2010) DOI: 10.1126/science.1197258

[makc]

chemist with chains was awesome

[neufer]

[b][color=#FF0000]a Ferengi from Star Trek[/color][/b]

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Click to play embedded YouTube video.

Are Aliens Among Us? Sort of, NASA Says
By John Brandon December 02, 2010

A scanning-electron micrograph image of arsenic-eating bacteria, which NASA says has redefined the quest for life in the universe.

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<<Alien life has been among us all along, according to new biological findings announced by NASA Thursday.

Research conducted by biochemist Dr. Felisa Wolfe-Simon from the U.S. Geological Survey has turned the quest for alien life on its ear, suggesting that phosphorous, carbon, and the other fundamental elements found in every living thing on Earth aren't the only signs of life. Wolfe-Simon will explain the findings at a hotly anticipated NASA press conference today at 2 p.m.

After a two-year study at California's Mono Lake, near Yosemite National Park, Wolfe-Simon found that a bug will grow in the presence of the toxic chemical arsenic when only slight traces of phosphorous are present. It's a radical finding, says molecular biologist Steven Benner, who is part of NASA's "Team Titan" and an expert on astrobiology -- forcing the space agency to redefine the quest for other life in the universe. "When we're searching for alien life, if it's not a Ferengi from Star Trek, what would it be?" Benner asked FoxNews.com. In his estimation, we've always defined life as something that has the exact same chemistry as a life-form on Earth. The new discovery will likely change that equation, because it means the basic building blocks of DNA are not quite what we thought. Benner, said the arsenic-loving organism at Mono Lake grew without high levels of the nutrient phosphate (although some phosphates were still present). Just as important, it could change how we look for alien life on other planets, especially on Saturn and the moons of Jupiter.

"It's a paradigm shift," says Dimitar Sasselov, an astrobiologist who leads the Origins of Life Initiative at Harvard University. "The possibility that Earth-life biochemistry is not universal is a transformational concept. It fills the search [for alien life] with optimism. NASA is moving in a good overall direction. What is needed is to take alternatives for life's chemistry to heart and fund research work better."

Arsenic is poisonous to nearly all forms of life on earth. Even small amounts of the poison become embedded in living tissue, causing liver failure and ultimately death -- in nearly everything BUT these bacteria.

However, as science fiction author Robert Sawyer told FoxNews.com, there could be even more profound implications. We have always looked for alien life that matches our biology, but now we have found a different life-form that uses arsenic in its basic DNA structure, he said. Sawyer explained that NASA science probes have always looked in the most likely places we thought life could exist -- on Mars or Europa, a moon of Jupiter. There is an old joke, he says, about how someone lost a quarter in their garage, then looks out in the yard for it. A neighbor asks why they are looking there instead of in the garage; the light is better, he answers.

"We tend to use the tools we know and the places we know to look for alien life," Sawyer said, explaining that humans want to find a walking, crawling alien and not one that just has different DNA. The change, he says, is that NASA will start looking for arsenic as well, and possibly other chemicals. This could mean new missions to Titan, which is known for having traces of arsenic. Another change could be the scientific equipment we send to space – probes might be retrofitted to search for arsenic.

Benner said the finding even impacts earlier research. Several years ago, when a Martian meteorite crash-landed on Earth, scientists examined it for the presence of phosphates. Now, it may be possible to re-visit some of the earlier findings. This hints at what experts call the "shadow biosphere" -- the existence of other life-forms, even on Earth, that have a radically different DNA structure. "It's a huge breakthrough. It changes the probabilities for their being life on other planets," Sawyer told FoxNews.com. "If there is more than one recipe that makes life, then there are chances of rolling the dice in a chemical soup of all over the universe, and the chances of that chemical soup giving rise to life is much larger."

For NASA, the scientific discovery could help the agency acquire new funding, serving as a catalyst to convince Congress to green light for new missions to Mars or Titan. In fact, the Internet buzz about finding alien life, as Sawyer noted, is partly due to how NASA has timed the announcement. A new Congress means new opportunities for scientific missions. He says the reality of the finding is somewhat of a joykill -- we have not found E.T. -- but there are still major implications for science and the search for extra-terrestrial life in our solar system and beyond.

Benner says the findings need further review -- there are questions about how much phosphorous is needed to sustain life. "The next phase is to grow more of the stuff in a lab using a defined cultured, maybe cook up a broth that contains no phosphorous at all, look at this with a critical eye," he said. However you view the announcement, the Lake Mono findings are profound, and the possibilities for finding life -- especially the primordial kind -- are now even greater.>>

[Chris Peterson]

Arsenic is poisonous to nearly all forms of life on earth. Even small amounts of the poison become embedded in living tissue, causing liver failure and ultimately death -- in nearly everything BUT these bacteria.

I think the really exciting news is that arsenic causes liver failure in other types of bacteria!

[neufer]

Arsenic is poisonous to nearly all forms of life on earth. Even small amounts of the poison become embedded in living tissue, causing liver failure and ultimately death -- in nearly everything BUT these bacteria.

I think the really exciting news is that arsenic causes liver failure in other types of bacteria!

Especially if they drink heavily!

[bystander]

Arsenic-Based Life

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[neufer]

Arsenic and Deep Space?
Dec. 2, 2010 | by Bill Nye

Note that arsenic is immediately below phosphorus on the Periodic Table of the Elements.

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<<If you or I ingest arsenic, well... it doesn't go so well. If you are, on the other hand, a certain species of bacterium from Mono Lake, California, ingesting this seemingly toxic metal is simple enough. You would have a way to use arsenic in the place of phosphorus -- not just in some chemical reactions, but in your very DNA, the instructions for living. Felisa Wolfe-Simon, a NASA Astrobiology Research Fellow, and her colleagues have found that a bacterium from the Halomonadace ae family of proteobacteria is able to completely swap arsenic for phosphorus.

Note that arsenic is immediately below phosphorus on the Periodic Table of the Elements. Perhaps you remember the silicon-based creature called horta in the original Star Trek series. The idea was that silicon is right below carbon in the periodic table; they are in the same chemical period. While swapping silicon for carbon is probably not a possibility, this is the same concept -- except that it's science, not science fiction. Arsenic is highly toxic to living things like us, but, chemically, it behaves in a similar way to phosphate.

Another exciting aspect of this discovery is that not only do these organisms live in an extreme environment, they are an extreme life form.

Who knows what other organisms are right under our noses that have perhaps taken it yet another step? They might not even use DNA at all. They could be an entirely different type of life. If these arsenic-lovers can be discovered in such a well-researched lake, who knows what else is out there, on our world or somewhere far, far away? This kind of research is an adventure. It helps us appreciate the remarkable nature of life on Earth. It helps us know our place in space. We at the Planetary Society will keep searching and encourage people everywhere to support this kind of research.>>

[Céline Richard]

Hello

What a surprise! This is a so great discovery
If life can develop by using arsenic, a toxic substance, instead of phosphor, in DNA, so we could imagine self-sustaining processes very different from the kind we currently know.
One day... maybe we could discover a form of life, using methane, instead of water? There are methane lakes in Titan, one of Saturn's satellites.

, from http://www.planetary.org/blog/article/00002796/; Another exciting aspect of this discovery is that not only do these organisms live in an extreme environment, they are an extreme life form.]

Yes, it is astonishing that in our planet, we can still discover mysteries, like extreme life forms, in the Mono Lake, in California! So the Earth might conceal many other secrets

It is strange some organism can live in very hostile environment, like in the surroundings of black smokers ("hydrothermal vents"?).
Here is a quotation from Wikipedia:

Although life is very sparse at these depths, black smokers are the center of entire ecosystems. Sunlight is nonexistent, so many organisms — such as archaea and extremophiles — convert the heat, methane, and sulfur compounds provided by black smokers into energy through a process called chemosynthesis. More complex life forms like clams and tubeworms feed on these organisms. The organisms at the base of the food chain also deposit minerals into the base of the black smoker, therefore completing the life cycle.

A species of phototrophic bacterium has been found living near a black smoker off the coast of Mexico at a depth of 2,500 m (8,200 ft). No sunlight penetrates that far into the waters. Instead, the bacteria, part of the Chlorobiaceae family, use the faint glow from the black smoker for photosynthesis. This is the first organism discovered in nature to exclusively use a light other than sunlight for photosynthesis.

New and unusual species are constantly being discovered in the neighborhood of black smokers – for instance, the Pompeii worm in the 1980s, and a scaly-foot gastropod in 2001 during an expedition to the Indian Ocean's Kairei hydrothermal vent field. The latter uses iron sulfides (pyrite and greigite) for the structure of its dermal sclerites (hardened body parts), instead of calcium carbonate. The extreme pressure of 2500 m of water (approximately 25 megapascals or 250 atmospheres) is thought to play a role in stabilizing iron sulfide for biological purposes. This armor plating probably serves as a defense against the venomous radula (teeth) of predatory snails in that community.

If we explore more the darkness of oceans, maybe we could discover some interesting bacteria, in order to make new medicine, to cure some horrible diseases.
There are so many issues at stake, not only fundamental questioning, when we try to understand what is life.

Have a very good day!

Céline

[neufer]

Click to play embedded YouTube video.

[Céline Richard]

Hello Neufer

Unfortunately, i can't read your image (or video?)... There is a red cross at the top of the empty square , where you put your image (video), on the left side... The same event occurred in the forum topic about "motivation and dreams".
I guess i am alone in this situation. I probably have a problem with my Internet i have to look for.
Have a very good day

Céline

[bystander]

Unfortunately, i can't read your image (or video?)...

it's a link to the YouTube video : http://www.youtube.com/watch?v=pCwpa8Pym_k

[Céline Richard]

Hello Bystander,

I guess the orange little balls represent Phosphore in DNA, while the green balls, which end by replacing the orange ones, are Arsenic.

Thank you!!!


Céline

[bystander]

http://asterisk.apod.com/viewtopic.php?f=9&t=22200

Arsenic life does not exist after all
New Scientist | 2012 Jan 27

Independent researchers find no evidence for arsenic life in Mono Lake
Discover Blogs | Bad Astronomy | 2012 Jan 23

Study challenges existence of arsenic-based life
Nature News | Erika Check Hayden | 2012 Jan 20

GFAJ-1 growth curves in limiting phosphate
RRResearch | Rosie Redfield | 2012 Jan 17