almost life

From: glenn morton (
Date: Sat Jan 22 2000 - 17:05:16 EST

  • Next message: Lawrence Johnston: "Re: almost life"

    Over last weekend I finished reading THe Fifth Miracle by Paul Davies. It
    is a fascinating, popular level account of the search for the origin of
    life. He reports some fascinating information about RNA research which
    comes very close to creating life in the testtube. I will quote him at length.

            "The Qb virus doesn't need anything as complicated as a cell in order to
    replicate: a test tube full of suitable chemicals is enough. The
    experiment, conducted by Sol Spiegelman of the University of Illinois,
    consisted of introducing the viral RNA into a medium containing the RNA's
    own replication enzyme, plus a supply of raw materials and some salts, and
    incubating the mixture. When Spiegelman did this, the system obligingly
    replicated the strands of naked RNA. Spiegelman then extracted some of the
    freshly synthesized RNA, put it in a separate nutrient solution, and let it
    multiply. He then decanted some of that RNA into yet another solution, and
    so on, in a series of steps.
            "The effect of allowing unrestricted replication was that the RNA that
    multiplied fastest won out, and got passed on to the 'next generation' in
    the series. The decanting operation therefore replaced, in a highly
    accelerated way, the basic competition process of Darwinian evolution,
    acting directly on the RNA. In this respect it resembled an RNA world.
            "Spiegelman's results were spectacular. As anticipated, copying errors
    occurred during replication. Relieved of the responsibility of working for
    a living and the need to manufacture protein coats, the spoon-fed RNA
    strands began to slim down, shedding parts of the genome that were no
    longer required and merely proved to be an encumbrance. The RNA molecules
    that could replicate the fastest simply out-multiplied the competition.
    After seventy-four generations, what started out as an RNA strand with
    4,500 nucleotide bases ended up as a dwarf genome with only 220 bases. This
    raw replicator with no frills attached could replicate very fast. It was
    dubbed Spiegelman's monster.
            "Incredible though Spiegelman's results were, an even bigger surprise lay
    in store. In 1974, Manfred Eigen and his colleagues also experimented with
    a chemical broth containing Qb replication enzyme and salts, and an
    energized form of the four bases that make up the building blocks of RNA.
    They tried varying the quantity of viral RNA initially added to the
    mixture. As the amount of input RNA was progressively reduced, the
    experimenters found that, with little competition, it enjoyed untrammeled
    exponential growth. Even a single RNA molecule added to the broth was
    enough to trigger a population explosion. But then something truly amazing
    was discovered. Replicating strands of RNA were still produced even when
    not a single molecule of viral RNA was added! To return to my architectural
    analogy, it was rather like throwing a pile of bricks into a giant mixer
    and producing, if not a house, then at least a garage. At first Eigen found
    the results hard to believe, and checked to see whether accidental
    contamination had occurred. Soon the experimenters convinced themselves
    that they were witnessing for the first time the spontaneous synthesis of
    RNA strands form their basic building blocks. Analysis revealed that under
    some experimental conditions the created RNA resembled Spiegelman's
    monster." Paul Davies, The Fifth Miracle, (New York: Simon and Schuster,
    1999), p.127-128

    He also notes that protein has been observed to self-reproduce:

            "Can proteins replicate unaided? Recently, Reza Ghadiri of the Scripps
    Institute in San Diego discovered that some small peptide chains can indeed
    self-replicate. Moreover, they can apparently correct replication errors
    'as if they had a mind of their own.' Another clue comes form the infamous
    mad-cow disease, or BSE, which has decimated British cattle stocks. Like
    scrapie and kuru, BSE is caused not by a bacterium or a virus, but by a
    fragment of protein that can replicate and spread. Might such fragments be
    surviving relics of a primitive life form based solely on proteins?" Paul
    Davies, The Fifth Miracle, (New York: Simon and Schuster, 1999), p. 133

    Christians who are basing a big part of their theology on the supposed
    inability of science to create life are likely making a big mistake. We
    should be preparing Christians for the real possibility that within the
    next century, science will create artificial life.


    Foundation, Fall and Flood
    Adam, Apes and Anthropology

    Lots of information on creation/evolution

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