Arsenic & Old Lace, I Mean Life
Jim Windle
So, if you haven't heard already, NASA has announced an upcoming announcement (so meta) about an "astrobiology finding." The press conference is at 2pm and streaming on NASA-TV: http://www.nasa.gov/multimedia/nasatv/index.html However, someone apparently ignored the embargo and leaked what is to be announced. Assuming that the leak is accurate, here are the basics: http://gizmodo.com/5704158/nasa-finds-new-life Basically, it sounds as if they have found a microbe in California that is the first to not share the same DNA as every other living thing on Earth. It replaces phosphorous with arsenic. "It's life, Jim. But not as we know it."
Jim Windle
(646) 470-9657
Oh, and be sure to state your name so my cyborg can tell me who is calling!
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http://www.nature.com/news/2010/101202/full/news.2010.645.html
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Bryan Bishop
So, if you haven't heard already, NASA has announced an upcoming announcement (so meta) about an "astrobiology finding." The press
http://www.ironlisa.com/WolfeSimon_etal_IJA2009.pdf
http://www.ironlisa.com/Oremland_etal_GeomicroJournal2009.pdf
http://www.ironlisa.com/Davies_etal_Astrobio2009.pdf
- Bryan
http://heybryan.org/
1 512 203 0507
Bryan Bishop
You can read Felisa's previous papers on the topic in the mean time:
http://www.ironlisa.com/WolfeSimon_etal_IJA2009.pdf
http://www.ironlisa.com/Oremland_etal_GeomicroJournal2009.pdf
http://www.ironlisa.com/Davies_etal_Astrobio2009.pdf
From: Eugen Leitl <eu...@leitl.org>
Date: Thu, Dec 2, 2010 at 12:12 PM
Subject: [biomed] [Act] Fwd: Re: New kind of bacteria discovered in Mono lake based on arsenic
To: t...@postbiota.org, bio...@postbiota.org
From: Amara Graps <am...@amara.com>
Date: Thu, 2 Dec 2010 10:59:23 -0700
To: a...@lists.crackmuppet.org
Subject: [Act] Fwd: Re: New kind of bacteria discovered in Mono lake based
on arsenic
And finally the official lifting of the embargo.
> Delivered-To: am...@amara.com
> Date: Thu, 2 Dec 2010 10:55:38 -0700
> To: am...@amara.com
> From: Joel Parker <jo...@boulder.swri.edu> (by way of Amara Graps)
> Subject: Re: New kind of bacteria discovered in Mono lake based on arsenic
> X-Recipe: procmailrc
>
>
> The AAAS Office of Public Programs is lifting the embargo,
> effective immediately, on the article "A Bacterium That Can
> Grow by Using Arsenic Instead of Phosphorous," by F. Wolfe-
> Simon and colleagues, because news reports disclosing the
> findings in the paper are now appearing online.
>
> The embargo is being lifted so that reporters may freely
> publish their coverage now. The rest of this week's SciPak
> content will remain under embargo until 2 pm US ET,
> Thursday, 02 December.
>
> A summary of the article follows, and a copy of the
> manuscript is available to registered reporters at
> http://www.eurekalert.org/jrnls/sci/.
>
> Please cite the journal Science and
> http://www.sciencemag.org in news coverage of this research.
>
> The paper itself will be available on Science site later
> this afternoon at
> http://www.sciencemag.org/lookup/doi/10.1126/science.1197258.
>
> A public video also has been posted to YouTube at
> http://www.youtube.com/watch?v=ObkqIMPmaJw. Additional
> freely accessible information also will be posted to
> EurekAlert! as soon as possible - look for a button at the
> top of the breaking news page.
>
> Thank you,
> The Science press package team
>
> RESEARCH SUMMARY:
>
> Living off Toxic Waste -- Bacteria That Munch on Arsenic:
> Can you imagine eating toxic waste for breakfast? In the
> journal Science, researchers have reported the discovery of
> a bacterium that can live and grow entirely off arsenic,
> reports a new study. The findings point for the first time
> to a microorganism that is able to use a toxic chemical
> (rather than the usual phosphate) to sustain growth and
> life. Arsenic is normally highly toxic to living organisms
> because it disrupts metabolic pathways, but chemically it
> behaves in a similar way to phosphate. Scientists have
> previously found organisms that can chemically alter
> arsenic; and these organisms have been implicated in ground
> water poisoning events in Bangladesh and other places in
> Asia when people have shifted to using borehole or well
> water to avoid cholera. Now, Felisa Wolfe-Simon and
> colleagues have found a bacterium able to completely swap
> arsenic for phosphorus to the extent that it can even
> incorporate arsenic into its DNA. The salt-loving bacteria,
> a member Halomonadaceae family of proteobacteria, came from
> the toxic and briny Mono Lake in California. In the lab, the
> researchers grew the bacteria in Petri dishes in which
> phosphate salt was gradually replaced by arsenic, until the
> bacteria could grow without needing phosphate, an essential
> building block for various macromolecules present in all
> cells, including nucleic acids, lipids and proteins. Using
> radio-tracers, the team closely followed the path of arsenic
> in the bacteria; from the chemical's uptake to its
> incorporation into various cellular components. Arsenic had
> completely replaced phosphate in the molecules of the
> bacteria, right down its DNA.
>
> Article #25: "A Bacterium That Can Grow by Using Arsenic
> Instead of Phosphorous," by F. Wolfe-Simon; P.C.W. Davies;
> A.D. Anbar at NASA Astrobiology Institute in Menlo Park, CA;
> F. Wolfe-Simon; J.S. Blum; T.R. Kulp; S.E. Hoeft; P.C.W.
> Davies; R.S. Oremland at U.S. Geological Survey in Menlo
> Park, CA; G.W. Gordon; A.D. Anbar; P.C.W. Davies at Arizona
> State University in Tempe, AZ; J. Pett-Ridge; P.K. Weber at
> Lawrence Livermore National Laboratory in Livermore, CA;
> J.F. Stolz at Duquesne University in Pittsburgh, PA; S.M.
> Webb at Stanford Synchrotron Radiation Lightsource in Menlo
> Park, CA.
--
Amara Graps, PhD www.amara.com
Research Scientist, Southwest Research Institute (SwRI), Boulder, Colorado
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Cathal Garvey
In brief, what they did was:
-Grow cells from a high-arsenic lake in California
-Gradually remove phosphate from the broth, and increase arsenic
-Eventually, for those cells still surviving, replace phosphate entirely with arsenic.
They found a gammaproteobacterium that survived the final stage of entire substitution. GPB include common, familiar guys like E.coli, so (unfortunately?) this bacteria is "Life but not as we know it". However, it's exciting as it hints at a whole layer of metabolism that can be unlocked and transferred to other organisms. You could potentially use this to bioremediate arsenic by incorporating it into stable, easily extracted proteins. You might be able to use its polymerases to do something strange and cunning with PCR or related reactions.
More interesting to me right now: Water is mostly absorbed in the large intestine, where most symbiotic bacteria live. What if you could use Arsenic-uptake and sequestration systems from this bacterium to make an Arsenic-binding probiotic to protect rural populations in deprived regions from arsenic laced water?
PRIOR ART RIGHT HERE, USPTO! :D
letters.cunningprojects.com
twitter.com/onetruecathal
http://www.indiebiotech.com
Cathal Garvey
Any other great ideas? Post them here, screw the monopolists!
Bryan Bishop
You can read Felisa's previous papers on the topic in the mean time:
http://www.ironlisa.com/WolfeSimon_etal_IJA2009.pdf
http://www.ironlisa.com/Oremland_etal_GeomicroJournal2009.pdf
http://www.ironlisa.com/Davies_etal_Astrobio2009.pdf
So I am wondering about DNA sequencing in this case. Because arsenate (AsO43−) is used in place of phosphate (PO43−) in GFAJ-1/Halomadaceae, I am not sure if traditional Sanger sequencing or even pyrosequencing would work, since they rely on reactions with phospherous-incorporated molecules.
The paper released today shows that the ratio of arsenic to phospherous is high specifically for the DNA content of GFA-J1. I think that, emperically, you could derive that from knowing the growth rate of the cell culture in a phospherous-limited environment (i.e. cell growth is roughly proportional to the number of copies of DNA, so if there's not enough phospherous to account for all of the DNA, something strange is up).
So, how would you do DNA sequencing for GFAJ-1? My favorite strategy is to always say AFM-DNA sequencing, but maybe there are other ideas. PCR with DNA polymerase might not be an option here, although DNA hybridization (i.e. on an array) might work?
Cory Tobin
> not sure if traditional Sanger sequencing or even pyrosequencing would work,
> since they rely on reactions with phospherous-incorporated molecules.
If you have a DNA polymerase that can handle both As and P, first do
PCR with P-nucleotides to make a 100% P copy of the sequence. Then do
the typical sequencing reaction with regular dideoxynucleotides.
Ideally you would use a thermostable polymerase capable of using both
P and As. But if none such polymerase exists you could use the
non-thermostable polymerase from this bacteria (which apparently has
no problem with both As and P) and add the polymerase after each cycle
- the method used for PCR before the discovery of thermostable
polymerases.
-Cory
Venkatesh Srinivas
> On Thu, Dec 2, 2010 at 12:49 PM, Bryan Bishop wrote:
>
>> You can read Felisa's previous papers on the topic in the mean time:
>> http://www.ironlisa.com/WolfeSimon_etal_IJA2009.pdf
>> http://www.ironlisa.com/Oremland_etal_GeomicroJournal2009.pdf
>> http://www.ironlisa.com/Davies_etal_Astrobio2009.pdf
>>
>
> So I am wondering about DNA sequencing in this case. Because arsenate (AsO4
> 3-) is used in place of phosphate (PO43-) in GFAJ-1/Halomadaceae, I am not
> sure if traditional Sanger sequencing or even pyrosequencing would work,
> since they rely on reactions with phospherous-incorporated molecules.
>
Chemical sequencing should still work; iirc Dimethyl Sulfate and Hydrazine
cleaved at specifically because of the structure of the base, not the
backbone.
-- vs
Andrew Barney
what other things are possible.
Cory Tobin
> I read the article earlier today. Fascinating stuff. Makes you wonder
> what other things are possible.
Here's a few ideas:
http://en.wikipedia.org/wiki/Hypothetical_types_of_biochemistry
-Cory
Venkatesh Srinivas
> Chemical sequencing should still work; iirc Dimethyl Sulfate and Hydrazine
> cleaved at specifically because of the structure of the base, not the
> backbone.
>
Hmm, I lie. Piperidine might not work on the arsenic diester linkages
(any chemists around who can say either way?)
-- vs
Bryan Bishop
> the first to not share the same DNA as every other living thing on Earth. It
> replaces phosphorous with arsenic.
Here's some commentary from another group:
On Thu, Dec 2, 2010 at 4:11 PM, sbharris1 <sbha...@earthlink.net> wrote:
> Interesting. There isn't any phosphorus in proteins anyway, so this would
> entirely be a phosphorus/DNA thing.
>
> The lightest elements in the periodic table tend to get used by life, simply
> because they're more common in the universe and on earth, due to
> nucleosyntheic reasons. Exceptions are elements 2-5. Helium can't be used
> for obvious reasons, and the next three really light elements aren't formed
> in stars and are therefore rare (Li and Be) aren't used at all, and one more
> (B) is used only in trace amounts (and then mostly by plants). So life is
> opportunistic. When it uses an element lower in the table in an analogous
> fashion to the element in the column above (like using selenium in place of
> sulfur, and tungsten in place of molybdenum) it's rarely successful, but
> cases are sometimes known, usually in bacteria. Arsenic instead of
> phosphorus (another bacterial trick) would be one more of these.
>
> I only know of one case where life uses a heavier element in a periodic
> table column without even use of the element above, and that's iodine. This
> is probably due to iodine's high concentration in the sea, and the fact that
> life on land couldn't get along without thyroid hormone (probably originally
> an antioxidant-source of iodide). By contrast, the lighter bromide is used
> by some lower ocean life (mostly algae), but not necessary for any land
> life, and only occasionally used. Iodine is the second heaviest element used
> by life, with only the occasional tungsten used by a few bacteria exceeding
> its heaviness. Iodine is way out in a class by itself, in that regard.
Bryan Bishop
Here's a few ideas:
http://en.wikipedia.org/wiki/Hypothetical_types_of_biochemistry
Surprisingly I never thought before "how would you sequence it" for strange forms of DNA/RNA- which is odd because the first thing I'd want to do if I ever found a sufficiently weird microbe is to sequence the hell out of its genome. Your previous suggestion for this case will work- just use a DNA polymerase from this organism. However, more exotic biochemistries might require some premeditation on hypothetical DNA-esque sequencing strategies.
Which reminds me.. Stuart Kauffman is one of the few theoretical biologists; who are the others? (Oddly enough I know of Stu primarily from his non-biology work in complexity science and NECSI ties.)
Brian Degger
"
for some reason, in the machinery of living things on Earth, one side
of the mirror goes almost wholly unused. All of us earthlings, from
algae to elephants, have proteins made of left-handed amino acids and
a genome of right-handed nucleic acids. (When chemists say handed,
they’re generally referring to the direction that polarized light
skews when beamed through a pure solution of the molecule.) No one
knows why LUCA picked one side of the mirror and not the other.|
They want to invent a mirro version, with right-handed amino acids and
left-landed nucleic acids.
mitchell porter
On Dec 3, 5:44 am, Cathal Garvey <cathalgar...@gmail.com> wrote:
> [arsenic bioremediation and other ideas]
Already noticed in the places where they have arsenic in the
groundwater:
http://www.telegraphindia.com/1101203/jsp/frontpage/story_13253120.jsp
Though they haven't yet thought of hacking human intestinal microflora
to make the rural populations themselves arsenic-tolerant. :-)
It occurs to me that effective bioremediation might be harder for
toxic chemical elements than it is for complex molecules, because you
can't lyse an atom. If the arsenic eaters die in situ, the arsenic
will just be returned to the environment. So there would have to be an
"arsenophile clean-up" stage as well.
Let us also bear in mind that this interpretation of the data isn't
proven yet, and there are mysteries to be explained if it's true:
http://www.csmonitor.com/Science/2010/1202/How-does-an-arsenic-based-life-form-work-exactly
> If you "replace all the phosphates by arsenates," in the backbone of DNA, he said,
> "every bond in that chain is going to hydrolyze [react with water and fall apart] with
> a half-life on the order of minutes, say 10 minutes."
>
> So "if there is an arsenate equivalent of DNA in that bug, it has to be seriously
> stabilized" by some as-yet-unknown mechanism, Benner said.
>
> Benner suggests that perhaps the trace contaminants in the growth medium
> Wolfe-Simon uses in her lab cultures are sufficient to supply the phosphorus
> needed for the cells' DNA. He thinks it's more likely that arsenic is being used
> elsewhere in the cells, in lipids for example.
>
> "Arsenate in lipids would be stable," said Benner, and would "not fall apart in
> water." What appears in Wolfe-Simon's gel-purified extraction to be arsenate
> DNA, he added, may actually be DNA containing a standard phosphate-based
> backbone, but with arsenate associated with it in some unidentified way.
I am reminded a little of the discovery of "nanobes" in Australia in
1996 - except that was serendipity; a group of microscopists were
studying geological samples and found filamentary structures. Back
then, Paul Davies showed up too, but in the Australian case I don't
think they ever got to the bottom of it. I know someone from that lab
and ask him every few years what the state of play is, but nothing is
happening; apparently the usual biochemical analytical techniques are
problematic to apply, so they have to wait for new analytical methods,
and meanwhile the world has moved on. It's hard to imagine the present
issue (is the arsenic in the DNA or not?) going unresolved for years,
given the hype of the present moment - but remember, way back NASA
held a press conference about possible nanobacteria in Martian
meteorites. And does anyone know without googling what the evidential
status of that idea is? I certainly don't.
Nathan McCorkle
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Rochester Institute of Technology
College of Science, Biotechnology/Bioinformatics
Cathal Garvey
Looks like epic fail on experimental design, folks.. http://ff.im/-uInbR
That paper will need some serious revision.
Sent from my Android.
On 3 Dec 2010 16:37, "Nathan McCorkle" <nmz...@gmail.com> wrote:
http://xkcd.com/829/
On Thu, Dec 2, 2010 at 6:50 PM, mitchell porter <mpo...@gmail.com> wrote:
>
> On Dec 3, 5:44 am, C...
--
Nathan McCorkle
Rochester Institute of Technology
College of Science, Biotechnology/Bioinformatics
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To po...
J. S. John
> Looks like epic fail on experimental design, folks.. http://ff.im/-uInbR
>
> That paper will need some serious revision.
>
of the NASA experiment. I read part way through and some points are
valid. I will have to read it again to fully understand it.
Cathal Garvey
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sgt york
phosphate contamination goes, both have the same flaw. The paper
claims that "the total intracellular P in the +As/-P cells was
consistently far below the quantity needed to support growth" and the
blog claims that there is enough contaminating P in the media to
support some growth. The flaw is that neither cite their claim, but to
varying degrees of guilt. This is almost expected in a blog, but
positively inexcusable in any peer-reviewed work. Much less something
with names like "NASA" and "Science" attached to it.
So, is the trace P in the +As/-P media enough for growth or not? The
answer will vary depending on what you're growing, so there's an easy
way to figure it out.
They had 4 culture conditions; +As/-P, -As/+P, +As/+P, and -As/-P.
However, because they know the +As/-P is really +As/lowP (they point
that out early on), they need to do a -As/LowP culture condition to
really be able to make the claim. If you do that and get no (or
significantly less) growth than you do in +As/-P, you know the
contaminating P is not enough to support growth and you've got your
Arsenic bug. If you really want to nail it, do a dose response curve.
Does it take off when you pass 100x the contamination levels?
Congratulations.
Every grad student should have it drilled into their skulls and
tattooed across the backs of their hands in bold letters so it shows
up through the gloves: "DETERMINATION AND USE OF PROPER CONTROLS WILL
MAKE OR BREAK YOUR PROJECT."
Controls, controls, controls! The data is meaningless without context,
and context is defined by your controls.
On Dec 6, 10:42 am, Cathal Garvey <cathalgar...@gmail.com> wrote:
> The blog post is certainly involved, but the key points I took from it are:
>
> 1) There was enough contaminating phosphate in all their media to support
> the observed cell density.
> 2) The quantities of measured and predicted phosphate vs. arsenic don't add
> up theoretically, or to the expected molar amount of either that would be
> expected if the cells were using one or both as part of the DNA backbone or
> essential cellular components.
> 3) They did very little work to prove adequately that the Arsenic was
> actually in the DNA backbone, or any other macromolecule.
>
> And from another review of her blog post:
> 4) The embargo served to bias everything toward publication, because there
> was little time for deliberation and experts were under NDA so couldn't
> lifting embargo was irresponsible.
>
> My own take on this is, if they wanted to prove her wrong the first,
> ridiculously simple thing they could do is to grow their cells beyond the
> threshold of phosphate-limited growth based on the predicted amount of
> contaminating phosphate. In other words, if X contaminating phosphate
> supports Y cells depending on phosphate, prove that you can grow >Y cells by
> a good margin in that medium by supplementation of other ingredients and
> patience. Other controls and experimental parameters should certainly
> follow, but the fact that their observed cell growth falls easily within the
> bounds of phosphate limitation is probably the biggest smoking gun in this
> whole affair.
>
>
>
>
> > On Sun, Dec 5, 2010 at 4:35 PM, Cathal Garvey <cathalgar...@gmail.com>
> > wrote:
> > > Looks like epic fail on experimental design, folks..http://ff.im/-uInbR
> > > That paper will need some serious revision.
>
> > How come no one is chiming in? The blog post is attacking the validity
> > of the NASA experiment. I read part way through and some points are
> > valid. I will have to read it again to fully understand it.
>
> > --
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Anselm Levskaya
The author of the blog is a working microbiologist and calculated the
needed P values from our well-attested knowledge of the molecular
constituents of bacterial cells. It was first-principles argument and
hardly needs a citation.
-anselm
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sgt york
certainly cite something like that in a paper. Not citing stuff, even
stuff you think is obvious, can really get you in trouble. Like I said
though, this isn't a paper, it's a blog post. Lack of citation in a
blog post is certainly not a big deal and I'm certainly not faulting
the blogger for it, I'm just pointing out that it weakens the author's
stance. I am faulting the NASA folks, though. They should have cited
it and that's what I was getting at when I said "to varying degrees of
guilt".
Besides, it's not really first principle; the constituents of an
organism will vary depending on what organism you're talking about,
what stage of growth it's in, what its overall metabolic state is,
etc.
But that doesn't really matter anyway as it's not a matter of
constituents, but a matter of requirements. Not how much is typically
found, but how much is needed for growth; specifically for the level
of growth observed. And as bacteria are well known for their
biochemical diversity, you really can't give a number for "all
bacteria," as they will all be different.
Cathal Garvey
I believe her number was based on guesstimated genome size and instantaneous RNA content. As you'd expect one phosphate per base, so two for each base-pair, you can certainly estimate the bare minimum requirement for any given cell if you know anything about these values.
And that is assuming, generously, that the cells somehow substitute something in place of phosphate for cellular energy (ATP) and enzyme activation (phosphorylation). Although I think she guesstimated that too.
Going from memory I think her genome estimate was even based on her knowledge of the proteobacterial genus the species is found in.
If it were a paper, it would have been nice to cite it. But then, if it were a paper, she's have put more accurate inputs and observations into her first-principals calculations and probably wouldn't have needed a citation at all.
Sent from my Android.
On 6 Dec 2010 21:16, "sgt york" <jv...@yahoo.com> wrote:
Eh, I'd still cite it. I'm a working biochemist and I would most
certainly cite something like that in a paper. Not citing stuff, even
stuff you think is obvious, can really get you in trouble. Like I said
though, this isn't a paper, it's a blog post. Lack of citation in a
blog post is certainly not a big deal and I'm certainly not faulting
the blogger for it, I'm just pointing out that it weakens the author's
stance. I am faulting the NASA folks, though. They should have cited
it and that's what I was getting at when I said "to varying degrees of
guilt".
Besides, it's not really first principle; the constituents of an
organism will vary depending on what organism you're talking about,
what stage of growth it's in, what its overall metabolic state is,
etc.
But that doesn't really matter anyway as it's not a matter of
constituents, but a matter of requirements. Not how much is typically
found, but how much is needed for growth; specifically for the level
of growth observed. And as bacteria are well known for their
biochemical diversity, you really can't give a number for "all
bacteria," as they will all be different.
On Dec 6, 2:52 pm, Anselm Levskaya <levsk...@gmail.com> wrote:
> sgt york:
>
> The author of the bl...
> On Mon, Dec 6, 2010 at 19:34, sgt york <jv...@yahoo.com> wrote:
> > I've read the primary article ...
> > For more options, visit this group athttp://groups.google.com/group/diybio?hl=en.
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sgt york
the envelope calculations based on assumptions. And that is all
*perfectly acceptable* on a blog or a web forum discussion.
My point is that the whole blog post really just casts doubt, most of
which can be easily addressed with the experiment I proposed above.
Looking back, I shouldn't have even mentioned the lack of citations,
it just detracted from the point of my post which was that the NASA
guys should have used the proper controls.
Jim Windle
http://scienceblogs.com/webeasties/2010/12/guest_post_arsenate-based_dna.php
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Tristan Eversole
On Dec 2, 2010, at 3:16 PM, Bryan Bishop wrote:
> Which reminds me.. Stuart Kauffman is one of the few theoretical biologists; who are the others? (Oddly enough I know of Stu primarily from his non-biology work in complexity science and NECSI ties.)
Well, there's always the Journal of Theoretical Biology (http://www.elsevier.com/wps/find/journaldescription.cws_home/622904/description#description ). :P
Aside from that, Manfred Eigen's quasispecies concept comes to mind, but his work is related to Kauffman's (with respect to hypercycles, anyway).
I would like to pick up the book "Evolutionary Dynamics: Exploring the Equations of Life" by Martin Nowak; "Robustness and Evolvability of Living Systems" looked good too. (But it's not as I don't have twenty billion things to read already. Kauffman's "Origins of Order" is what I'm reading now, coincidentally.) In general, ecology and evolution have large theoretical components, but that's probably not what you are looking for.
--T.
Jay Woods
Extraordinary claims require extraordinary proof.
http://en.wikipedia.org/wiki/Marcello_Truzzi#.22Extraordinary_claims.22
http://www.gutenberg.org/ebooks/9662 - Hume - note that the URL in
wikipedia is dead.
Also note that the URL in wikipedia for Laplace is dead. Furthermore the
quoted form can't be found. However, the following form can be found.
"From what precedes, we ought generally to conclude
that the more extraordinary the event, the greater the
need of its being supported by strong proofs. "
http://www.archive.org/details/aphilosophicale00laplgoog
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Jim Windle
http://twitter.com/#!/ironlisa/status/11579028288839680
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J. S. John
> This seems like a funny position for some who just had a press conference to
> announce their results to take.
>
> http://twitter.com/#!/ironlisa/status/11579028288839680
>
I half asleep right now so I don't understand what you said.
And what does ironlisa mean by "Discussion about scientific details
MUST be within a scientific venue so that we can come back to the
public with a unified understanding."?
Jim Windle
On Tue, Dec 7, 2010 at 8:39 AM, Jim Windle <jim.w...@gmail.com> wrote:I half asleep right now so I don't understand what you said.
> This seems like a funny position for some who just had a press conference to
> announce their results to take.
>
> http://twitter.com/#!/ironlisa/status/11579028288839680
>
And what does ironlisa mean by "Discussion about scientific details
MUST be within a scientific venue so that we can come back to the
public with a unified understanding."?
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J. S. John
>>
> My point was simply that it seems inconsistent to me that someone who
> announced their results via a press conference would demand that discussion
> of those results only take place in a "scientific venue". Like you I am not
> sure what she means by that.
>
>>
>> And what does ironlisa mean by "Discussion about scientific details
>> MUST be within a scientific venue so that we can come back to the
>> public with a unified understanding."?
>>
This discovery is monumental but how come I don't hear much about it
in the media. I'll have to wait and see if they got something on
"Science Friday". Why don't I hear companies planning on using this
bug for bioremediation?
Here is a good overall account of what's being said:
http://www.guardian.co.uk/science/2010/dec/02/nasa-life-form-bacteria-arsenic
The one statement that troubled me was:
"'We cannot indiscriminately wade into a media forum for debate at
this time,' declared senior author Ronald Oremland of the U.S.
Geological Survey. 'If we are wrong, then other scientists should be
motivated to reproduce our findings. If we are right (and I am
strongly convinced that we are) our competitors will agree and help to
advance our understanding of this phenomenon. I am eager for them to
do so.'
Why does he say reproduce the results if they're wrong only? Shouldn't
you also try to reproduce if you're right also. How can you be right
unless others get the same results also? Maybe he chose his words
poorly but this debacle makes me further question American science.
What happened to all the Edisons and Teslas? True scientists, not a
bunch of PhD toting academics who live in their labs and theorize.
Margaret
I'm trying biology DIY in a different way--no lab (at least not now)
but trying to engage in the discussion over stem cells, cancer stem
cells and models of carcinogenesis. Can anyone steer me toward other
interested parties? Mostly I can get published articles off the
Internet, or go to "the library" when needed--I refuse to pay $30 to
download an article--especially since I live 6 blocks from the
UC-Berkeley Biology Library. However, this does not give me
anyone to bounce ideas around or insight into unpublished
information. Any leads/sources/discussion groups, etc. would be much
appreciated.
I read about your "wet-lab" projects with interest. If one of your
projects REALLY works out, in a beyond your wildest dreams way, what
wil your do about it?
---Margot