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Liquid Crystal Phases of DNA, Beginning of Life?

Posted by CmdrTaco on from the lot-better-than-my-theory-of-gum-and-scotch-tape dept.

An anonymous reader writes "A team led by the University of Colorado at Boulder and the University of Milan has discovered some unexpected forms of liquid crystals of ultrashort DNA molecules immersed in water, providing a new scenario for a key step in the emergence of life on Earth. CU-Boulder physics Professor Noel Clark said the team found that surprisingly short segments of DNA, life's molecular carrier of genetic information, could assemble into several distinct liquid crystal phases that "self-orient" parallel to one another and stack into columns when placed in a water solution. Life is widely believed to have emerged as segments of DNA- or RNA-like molecules in a prebiotic "soup" solution of ancient organic molecules.

16 of 150 comments (clear)

  1. Life? by Random+BedHead+Ed · · Score: 3, Funny

    Life was started when the Great Green Arkleseizure sneezed it across the universe to this location. Stop shattering my worldview with these so-called "discoveries."

    1. Re:Life? by Kjella · · Score: 4, Insightful

      Obviously off on the religious mockery tangent, but this isn't really offtopic. If (I'd say when) we discover how to make life from inanimate matter, there's bound to be yet another clash between Genesis and Abiogenesis. And some people will yet again claim that the Book is right and science is wrong. Obviously religion gets a lot less personal if God is someone that once snapped his fingers and there was a Big Bang - and that everything that follows can be replicated in a test tube. But I think that we in the not too distant future will make the connection from inanimate molecules into primitive replicating beings. And if God doesn't smite us down at that point for invading his turf he never will.

      --
      Live today, because you never know what tomorrow brings
    2. Re:Life? by brainnolo · · Score: 2, Insightful

      The fact that you do not get it, or nobody gets it does not mean that there is no explanation. Our brain is amazing but I doubt that it is the top intelligence ever achievable by a living creature, so it is plausible that we are just not intelligent enough to understand some things.

    3. Re:Life? by foniksonik · · Score: 5, Insightful

      We're plenty intelligent enough... we just don't have enough data and probably never will, but we can make guesses - more educated guesses than those made by early philosophers (religious academics and natural academics). Personally I don't see the disconnect between early science/religion and modern science. They sought answers with what information they had available.. we do the same. Just because some cult of people want to believe that we were at the pinnacle of understanding some 2 - 3 thousand years ago, doesn't discount the efforts made at the time.

      Those Rabbis, Greeks and monks were very smart people - they also had to deal with politics and ignorance however and sometimes the best way to deal with that is to dumb it down to a lowest common denominator. "That's right, God made that happen. Don't go to war over it... it was a miracle. Now give us money so we can keep teaching your kids how to read/write and count to ten."

      --
      A fool throws a stone into a well and a thousand sages can not remove it.
  2. neat by wizardforce · · Score: 4, Interesting
    "The key observation with respect to early life is that this aggregation of nano DNA strands is possible only if they form duplexes," Clark said. "In a sample of chains in which the bases don't match and the chains can't form helical duplexes, we did not observe liquid crystal ordering."

    The CU-Boulder and University of Milan team began a series of experiments to see how short the DNA segments could be and still show liquid crystal ordering, said Clark. The team found that even a DNA segment as short as six bases, when paired with a complementary segment that together measured just two nanometers long and two nanometers in diameter, could still assemble itself into the liquid crystal phases, in spite of having almost no elongation in shape. Subsequent tests by the team involved mixed solutions of complementary and noncomplementary DNA segments, said Clark. The results indicated that essentially all of the complementary DNA bits condensed out in the form of liquid crystal droplets, physically separating them from the noncomplementary DNA segments. "We found this to be a remarkable result," Clark said. "It means that small molecules with the ability to pair up the right way can seek each other out and collect together into drops that are internally self-organized to facilitate the growth of larger pairable molecules. "In essence, the liquid crystal phase condensation selects the appropriate molecular components, and with the right chemistry would evolve larger molecules tuned to stabilize the liquid crystal phase. If this is correct, the linear polymer shape of DNA itself is a vestige of formation by liquid crystal order."
    one of the requirements for life is that you have an environment that supports molecular self assembly and recognition, this experiment seems to show that this is the case with DNA and RNA strands as short as 6 bases and can select for more stable configurations over time. It's the beginnings of evolutionary natural selection- base pairs assemble into structures that have certain desireable characteristics.
    --
    Sigs are too short to say anything truly profound so read the above post instead.
  3. Re:from ooze we came? by ScentCone · · Score: 2, Insightful

    do not be dismayed, it is the way it was meant to be

    I'm curious. Do you ever, you know, actually read your own posts? Unpunctuated, case-mangled, non-sequitor-ish loony ramblings have the very subtle effect of, you know, making you look like a simpering, witless, theo-clown. Just sayin'. Other than that, have a great weekend!

    --
    Don't disappoint your bird dog. Go to the range.
  4. not intelligent enough... by CrazedWalrus · · Score: 4, Insightful

    ...Or don't have the proper perspective. For example, consider one of those huge walk-through mazes. Those things are dog-simple when seen from above, but when you're inside of it, it can take an hour to get out. You do eventually get out, but it takes a lot longer to solve that way than the seconds it would take when seen from a better point of view.

    I'm personally of the opinion that nothing science concludes will ever be able to prove or disprove the existence of (a) God(s), so I'm not sure why this discussion keeps coming up. Yeah, science never "proves", only "shows to be likely", whatever. The point is that you either believe in God or you don't. There's no scientifically veritable "correct" answer that can ever be had until some day in the future when it's too late to do anything about it anyway. You're either worm food or in your final eternal resting place... wherever that may be.

    Honestly, the religion bashing is completely pointless and is getting really, really old hat.

    1. Re:not intelligent enough... by brainnolo · · Score: 2, Interesting

      Religion bashing may be pointless but, like governments, the main religious organizations are very influent, powerful and rich (and unlike governments they do not offer any tangible service). I'm all for free thinking but for example the Roman Church has been involved in many scandals and crimes against humanity (crusades comes to mind obviously) and they are never punished for their actions. If my opinion was worth something religious organization wouldn't be allowed or would be controlled as tightly (or even more) as corporations. Corporations which do not even need to prove the existence, let alone the quality of what they sell (the hope of life after death).

    2. Re:not intelligent enough... by Daniel+Dvorkin · · Score: 5, Insightful

      I'm personally of the opinion that nothing science concludes will ever be able to prove or disprove the existence of (a) God(s), so I'm not sure why this discussion keeps coming up.

      It keeps coming up because religious ideologues keep insisting that science is wrong because it contradicts their beliefs. And they want to base public policy and education on those beliefs. The beliefs themselves are a personal matter, of course, and they've got every right to believe that Rapture is imminent or that life was created in its current form 6000 years ago; the conflict occurs when they try to base things like environmental management or what's taught in high-school science classes on it.

      Honestly, the religion bashing is completely pointless and is getting really, really old hat.

      The science bashing isn't pointless at all -- it's a means of gaining political power -- but it's definitely old hat, which doesn't keep fanatics from doing it. Scientists who bash religion, e.g. Dawkins, do so out of disgust with religion's continual insistence on trying to replace knowledge with ignorance, and the consequences thereof.

      --
      The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
    3. Re:not intelligent enough... by Daniel+Dvorkin · · Score: 4, Insightful

      However, religion bashing has come to a point where even admitting of being religious is a cause of ridicule or arrogance.

      [shrug] I haven't seen that; I have seen a lot of religious believers being hypersensitive and interpreting fanatic-bashing as religion-bashing generally. E.g., when someone attempts to jump in on a discussion of the origins of DNA in the early terrestrial environment with, "That can't be true because Genesis says ..." then mockery is the only reasonable response. That's not religion-bashing, that's fanatic-bashing. If you are willing to accomodate your religious beliefs to scientific observations, as many religious scientists have done, then hardly anyone is going to attack you for it. (And those who do can be ignored; there are cranks and professional malcontents on both sides of every argument.)

      I do science and I am religious. Is there something wrong in that?

      Of course not. Motivation is irrelevant when science is done right. You can study a problem because you have a personal interest in solving it, because you want to unravel the mysteries of God's creation, because someone is paying you a whole lot of money to do so, or just out of simple curiosity -- all of these motivations can produce good science, and will no doubt continue to do so. But it's important to acknowledge that some motivations are more likely to lead to bias than others; and it is absurd to deny that religion has introduced considerable bias into the study of the origins of life.

      --
      The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
    4. Re:not intelligent enough... by Anonymous Coward · · Score: 3, Interesting

      However, religion bashing has come to a point where even admitting of being religious is a cause of ridicule or arrogance. Gee I wonder why? Oh that's right, it's because most often "your religion" has some pretty nasty things to say about the rest of us. Such as suffering in eternal agony unless we reciprocate the love of your god or prophet. When was the last anti-Buddhist rant you've heard or read? Ever? Stop trying to pass off being spiritual as having an organized set of beliefs that you must adhere to and coerce others to adhere to as well. I consider myself a very spiritual person but I'm still an atheist and an agnostic. It's not bashing of beliefs, customs or traditions, it's the rational rejection of questionable claims. God has never claimed to exist. It's not like God is the shining sun, I can feel the heat and I can see the light but I'm just some asshole rejecting it. I'm not walking around tripping over God and then willfully disbelieving out of spite or arrogance. The existence of God is non-obvious, therefore the burden of proof remains squarely on those making the claims, no matter what kind of flawed thought-process you follow. As for my idea of "God" it's more of a nomological necessity similar to the fundamental force of gravity rather than a personal deity with two eyes, ears, arms, legs and testicles. Seriously, that idea of a god that your parents taught you out of an uncorroborated book written by Stone Age peasants is laughable and you really do only deserve ridicule and shame, if and only if you've been presented with all this evidence and still hold true that Jesus Christ is the only way God could come up with to save us from his dysfunctional Universe.

      And if you don't like it, fuck you.
    5. Re:not intelligent enough... by Pax681 · · Score: 2, Insightful

      erm... pope boniface orderd the first crusade... against ther muslims.... to get jerusalem and the "holy land" into charistian hands....... there fore the church of rome ordered the crusades ad backed ALL of the crusades. to say this wasn't a war of religion..which it BLATANTLY was , AND to then say read books on it is quite frankly amazing. you see when the poster reads up on it he will see that it was a war of religion. i give talk on a semi regular basis about the Templars, their history, the crusades and such and have been on UK radio talking abot them on more than one occassion. i am by no means the leading world expert but i would say i am competant in my knowledge and recgnised as such by groups, organisations and radio(BBC Scotland being one of them) you can try to wish away the absolute fact that there have been more torture, deaths ,murders,attempted genocides and general inhumanity(look to the cathars for a start) in the name of religion to utterly quash your statement. and Christianty(both roman and non roman) does have to shoulder it's burden there(yes jesus pun intended)

    6. Re:not intelligent enough... by moz25 · · Score: 2, Interesting

      Don't forget that tolerance works both ways - from "less open" to "more open" and from "more open" to "less open".

      I have no issue whatsoever with people who keep their religion to themselves or who behave in ways that I would expect, i.e. modest, kind and forgiving. I know people who are like that and I have no troubles with them.

      Instead, we are confronted almost daily with "proud Christians" who are so intensely narrowminded that they cannot even comprehend that we do not secretly believe in God and by extension fear God. I never understand the logic behind yelling "you'll go to Hell for [insert triviality]!!" to someone who doesn't believe in a Hell.

      Now you'll probably claim those people aren't "real Christians", but realize they are vocal and cannot be ignored. As you know, they are very active politically. Heck, if you're active in politics, your best bet is to claim you're religious even if you're not. Too many people associate it with being "good".

      Let's not get into the specifics of your particular religion, because IMO if you take a step back, it is rather ridiculous. So many things are taken out of context, interpreted to fit biases or simply translated incorrectly. For example, "Jesus walks ON water" is written same as "Jesus wants NEXT TO water" in the original language.

      Then the whole anti-homo stuff... jeez. Only 0.02% of the whole book can be interpreted to be about gays somehow and even that can be explained away through context and interpretation (e.g. good luck following all the rules in Leviticus). Yet Christianity appears to be all about sexuality and homosexuality in particular. That's what they're really vocal about and even base voting decisions on.

      Then there's the Jesus guy... an illiterate carpenter who care about poor sick people. While I don't believe he had any powers, I can run a thought experiment of "what would Jesus do". Well, it's *really* hard for me to imagine that such a figure would endorse any of the smug bigoted consumption-oriented Christians of today.

      Can you at least see how modern implementation of religion doesn't even inherently bash logic, but even conflict with its own roots?

      I really wish we as a humanity could put all this rubbish behind us. On the other hand, humanity being what it is, we could most likely expect something even worse (e.g. Scientology)...

      --
      see a Text Widget
  5. God of the Gaps by Liquidrage · · Score: 3, Insightful

    It's shrinking. One day they'll be no place to hide.

  6. Re:How Did the DNA Strands Form? by harrv · · Score: 2, Informative

    In "The God Delusion" by Richard Dawkins, he makes the point that there are approximately a billion billion planets in the universe within the so-called "goldilocks zone", that is, capable of sustaining life because they probably have liquid water. So, even if the likelihood of DNA or RNA randomly forming was a billion-to-one, that would still mean that it has happened on a billion planets.

  7. Not excited yet by sammysheep · · Score: 2, Insightful

    First, we need the spontaneous formation of a membrane that can selectively remove calcium. Calcium at higher concentrations is cytotoxic and will aggregate proteins/nucleic acids. Calcium regulation is therefore tight and ubiquitous in living things. See article.

    Given such a membrane and some short DNA polymers, we also need to translate this random "information" into something meaningful. The current mechanism is: DNA -> RNA -> PROTEIN. This requires RNA polymerase or, at least, some ribosome-like enzyme to make a protein product. These enzymes are usually proteinaceous themselves--catch 22. We also need a DNA polymerase for replication if we wish to propagate our newly acquired "information".

    I am more interested in how this spontaneous aggregation of DNA crystals could play a role in living cells.