Metabolism appears in lab without cells | Hacker News Reader

Metabolism appears in lab without cells

newscientist.com

154 pointschewxy23 comments

The full paper[1] is interesting, as is the news and views commentary on this article[2] from the same Molecular Systems Biology journal. The origin of life is, of course, still an unsolved problem, and one of the problems has been inferring from geological and other findings what the early environment of Earth was in which life arose. I commend the Hacker News participant here who submitted this article for submitting an article from a journalistic source experienced in science journalism, with a reporter making the effort to seek other commenters besides the primary research journal authors to gain pro-and-con commentary about how important this preliminary finding is. I found the submission interesting, as it suggests some lines of inquiry I hadn't read about before in other writings on the origin of life.

[1] http://msb.embopress.org/content/10/4/725

[2] http://msb.embopress.org/content/10/4/729

I'm with Szotack (quote at end of article). Basically, they're just showing relatively obvious stuff, which is to say, the second law of thermodynamics coupled with a heat bath can lead to interesting deviations from entropy.

The difference is that absent a cell doing what Szotack claims (i.e. evolving in front of him) his theory is basically unprovable and unfalsifiable. The other group stand a chance of eventually reconstructing what they're looking for, but the alternative being presented is just pontification.

  from complex sugars to simpler molecules

Are they saying they've found non-cell metabolic pathways... but that require cell-created complex sugars as starting points? OK, so not enough to start life; but filling in each link in the chain (tree?) is important.

BTW: some researchers extrapolated life-complexity-over-time backwards, and concluded life is older than Earth. Speculation on speculation! But a fascinating paper: https://news.ycombinator.com/item?id=5552381

The DOI is wrong. Here's the paper: http://msb.embopress.org/content/10/4/725.

A non-biologist summary: some complex compositions like sugars have been found to decompose (metabolize) outside of a cell. The research still does not explain how such compositions can form in the first place.

Journalists look for sensational titles and words so the scientific paper is probably less "spark"ling.

Regardless, it is encouraging that with every step scientists are getting closer to explaining one of the greatest scientific mysteries and one of the biggest dark holes where religious supernatural beings and deities happen to skulk.

I wonder what the creationists will say about this :P

See, this is what bothers me. Too many people seem to think that there is a conflict between evolution and creationism. The thing is, both can in fact be true. Who's to say that there isn't a creator orchestrating processes? Such a being wouldn't work by magic, but by a profound understanding of natural processes. How would this be any different from us discovering how life was created and then using that understanding to create it ourselves? The whole back and forth over evolution between religious and non-religious folk is ridiculous. Neither side will ever get anywhere because the whole premise of the debate is a non sequitur.

You might be less bothered if you took creationist in this context to imply "young earth creationist," which is almost certainly what's intended.

Yeah, that's what I meant, sorry. YEC are really the ones making most of the noise and raising most of the money for stuff like school board electiosn, so...

There isn't sufficient (any) evidence to justify belief in a creator, magical or not. You are free to believe that there might be a creator, but it isn't any more rigorous than believing in unicorns or flying spaghetti monsters. I realize this isn't r/atheism, but it bothers me that otherwise scientifically minded people allow themselves a soft spot in their ontology to incorporate cultural myths.

I never stated whether I believe in a creator being or not, nor will I since it is not relevant to this conversation. The belief that a creator is orchestrating things is what's known in science as a theory. The point I was making is that neither theory is mutually exclusive. It does not follow that if one is true, then the other is not.

Also, if you are indeed scientifically minded then you must be open minded to all theories that explain the state of things unless there is sufficient evidence to the contrary. It is not enough to say that there isn't sufficient evidence. Remember, the absence of evidence is not the evidence of absence. To rule out a theory that could explain our observations without evidence is not scientifically minded at all.

To have a productive conversation, if you believe that the two theories are mutually exclusive then please explain what about one of them being true, means the other cannot be. If you don't believe they are mutually exclusive then my original point stands that the statement by 'spiritplumber' is a non sequitur.

I'll simply repeat what I said already: the belief in a creator is as arbitrary as belief in unicorns or the flying spaghetti monster. The only thing that distinguishes it is its long running place in cultural mythology. I highly doubt you'd be presenting the point were it not for your personal belief.

>>> musings >>>

Let's invert the question: can we create, in our labs or in computer simulation, artificial life that could not reliably trace its origins to us specifically?

What would it take to create a (seemingly) self-contained, self-organized environment for the artificial life to live in?

<<< musings <<<

Don't hold your breath; it's gonna take 4 billion years.

Scientists need to be extraordinarily careful about this kind of vague, "might be", "coulda been" kind of speculation. Finding the "spark of life" would be amazing, but speculating about how it might have formed without actual evidence shows a lack of skepticism that runs counter to the whole ethos of science and ultimately undermines it. When the public sees scientists hoping and wishing that they can find the "spark of life," and raising up hands of praise when some vague suggestion of how it might have happened is proffered, they're bound to gain suspicions that this part of science, anyway, is nearer to a religion that a cold, surgical pursuit of verifiable truth.

If you don't see the handwaving speculative wishfulness of the article, note this sentence: "A related issue is that the reactions observed so far only go in one direction; from complex sugars to simpler molecules like pyruvate." Ah, so when you heat up sugars they decompose into simpler molecules? Amazing! Must have created life! God is dead; long live Nature! Praise be!

I wouldn't characterize it in such an extreme way. This kind of educated guessing, beard-scratching and "coffee house hypothesizing" is exactly how some of the raw ideas in science are generated.

But yes, I agree with your basic premise of skepticism. No one should accept these ideas because they want them to be true. To me it doesn't sound like magical thinking so much as thinking out loud to involve other scientists in the conversation. Is that a problem?

It sounds like your concern is more with the language of Linda Geddes, who wrote the New Scientist article, than with the scientists. Are you sure your caution shouldn't instead be more applied to science journalists?

For example, the "spark of life" is from the New Scientist, not from the researchers, and the word "spark" doesn't exist in the underlying paper except in the references, in the title of another paper.

Nor does the paper say something as simple as "when you heat up sugars ...". Instead:

> Due to the complexity of the metabolic pathways, it has been argued that metabolism‐like chemical reaction sequences are unlikely to be catalysed by simple environmental catalysts (Lazcano & Miller, 1999; Anet, 2004). However, to our knowledge, this possibility has not been tested systematically, and at present stage, thermodynamic approaches are not predictive about which molecules form in the presence of simple catalysts from a precursor (Amend et al, 2013). Here, we studied the reactivity of intermediates of glycolysis and the pentose phosphate pathway upon replicating a plausible chemical composition of the prebiotic Archean ocean. We report that under these conditions, the intermediates of the two pathways undergo non‐enzymatic interconversion reactions and form neighbouring intermediates that constitute these pathways in modern cells.

That is, the goal was to look for 'metabolism‐like chemical reaction sequences', and not the creation of more complex sugars.

I agree regarding science journalists and feel the need to put this here: http://www.phdcomics.com/comics.php?n=1174

When a scientist says "an explanation for X could be Y" it shouldn't be interpreted as "here's a guess, I want it to be true and am undermining science", rather it's a sign they are being extraordinarily careful but they're reporting that they have observed some evidence which appears to agree with a given hypothesis.

Also I suggest reviewing high school biology, glycolysis isn't simple the breakdown of glucose into simpler molecules but involves many seemingly complex stages of isomerisation and reactions which are shepherded under specific conditions within various enzyme's active sites.

Consider reading the paper for more information: http://msb.embopress.org/content/10/4/725

> high school biology, glycolysis isn't simple the breakdown of glucose into simpler molecules but involves many seemingly complex stages of isomerisation and reactions which are shepherded under specific conditions within various enzyme's active sites

That's more like college level biology there. In high school biology I learned something along the lines of "sugar is used to produce ATP, and ATP is energy". (I was pretty skeptical of the tail end of this claim even then.)

>>Scientists need to be extraordinarily careful about this kind of vague, "might be", "coulda been" kind of speculation.

Speculation is built into the scientific method itself. It's called "hypothesis."

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