Posted on 11/16/2005 3:40:35 AM PST by snarks_when_bored
* 14:02 15 November 2005
* NewScientist.com news service
* Gaia Vince
A new microscope sensitive enough to track the real-time motion of a single protein, right down to the scale of its individual atoms, has revealed how genes are copied from DNA – a process essential to life.
The novel device allows users to achieve the highest-resolution measurements ever, equivalent to the diameter of a single hydrogen atom, says Steven Block, who designed it with colleagues at Stanford University in California.
Block was able to use the microscope to track a molecule of DNA from an E.coli bacterium, settling a long-standing scientific debate about the precise method in which genetic material is copied for use.
The molecular double-helix of DNA resembles a twisted ladder consisting of two strands connected by “rungs” called bases. The bases, which are known by the abbreviations A, T, G and C, encode genetic information, and the sequence in which they appear “spell out” different genes.
Every time a new protein is made, the genetic information for that protein must first be transcribed from its DNA blueprint. The transcriber, an enzyme called RNA polymerase (RNAP), latches on to the DNA ladder and pulls a small section apart lengthwise. As it works its way down the section of DNA, RNAP copies the sequence of bases and builds a complementary strand of RNA – the first step in a new protein.
“For years, people have known that RNA is made up one base at a time,” Block says. “But that has left open the question of whether the RNAP enzyme actually climbs up the DNA ladder one rung at a time, or does it move instead in chunks – for example, does it add three bases, then jump along and add another three bases.
Light and helium
In order to settle the question, the researchers designed equipment that was able to very accurately monitor the movements of a single DNA molecule.
Block chemically bonded one end of the DNA length to a glass bead. The bead was just 1 micrometre across, a thousand times the length of the DNA molecule and, crucially, a billion times its volume. He then bonded the RNAP enzyme to another bead. Both beads were placed in a watery substrate on a microscope slide.
Using mirrors, he then focused two infrared laser beams down onto each bead. Because the glass bead was in water, there was a refractive (optical density) difference between the glass and water, which caused the laser to bend and focus the light so that Block knew exactly where each bead was.
But in dealing with such small objects, he could not afford any of the normal wobbles in the light that occur when the photons have to pass through different densities of air at differing temperatures. So, he encased the whole microscope in a box containing helium. Helium has a very low refractive index so, even if temperature fluctuations occurred, the effect would be too small to matter.
One by one
The group then manipulated one of the glass beads until the RNAP latched on to a rung on the DNA molecule. As the enzyme moved along the bases, it tugged the glass bead it was bonded too, moving the two beads toward each together. The RNAP jerked along the DNA, pausing between jerks to churn out RNA transcribed bases. It was by precisely measuring the lengths of the jerks that Block determined how many bases it transcribed each time.
“The RNAP climbs the DNA ladder one base pair at a time – that is probably the right answer,” he says.
“It’s a very neat system – amazing to be able see molecular details and work out how DNA is transcribed for the first time,” said Justin Molloy, who has pioneered similar work at the National Institute for Medical Research, London. “It’s pretty incredible. You would never have believed it could be possible 10 years ago.”
Journal reference: Nature (DOI: 10.1038/nature04268)
Very interesting story.
Bttt.
Why would I have to verify the claim? By its very nature it is unverifiable. That is the nature of the problem that ID would introduce into science. To take the opposite case, if the flagellum did appear to evolve how could you discount the proposition that the Designer dunnit? You cannot, because ID is not science. By the very nature of its claims it is unfalsifiable.
This sounds like you ducking your own statement.
If this is your cheap and dishonest way of trying to falsely imply that I have lied on this thread, then thanks for further reinforcing my point about the dishonesties on *your* side of the discussion.
It is not an implication. I am saying it straight out: you are being dishonest in this discussion. You consistently mischaracterize the issues under discussion, consistently make false accusations about the people involved, and consistently misrepresent the position of those who take a view different from your own.
Precisely. They are the ones who declare ID to be "unscientific" merely because it implies a Creator. Narrow minds and all that. They are the ones who would exclude inferences, implications, possibilities, hunches, and the like as being "unscientific." Fortunately they do not corner the market in science, let alone truth and education in general.
Any wino living in a cardboard carton if free to conjure up his own definition of science. But he only talks to other winos, and occasional welfare workers. And no one cares what they think about science.
ID literature repeatedly states that it places no constraints on the designer. The designer could be anyone or anything, with no implied limits as to powers or motivation. If you want to place constraints on the designer then you'd better say what they are and why you've chosen those constraints, then we'll be able to judge if the designer may have been fiddling with our experiments.
We can see from the various "nature cleverly invented" popularizations of evolution, that the solution space of nature is entirely "scrutable" to us: we understand the optimization path in question, because it's often quite similar to how we would approach similar problems. We also understand that human ID decisions are generally are made for entirely understandable and practical reasons -- and probably never for "inscrutable" ones.
Very true and absolutely nothing to do with ID.
Again, you are mistaking your initial presumption for an established truth.
Matter is organized. That implies design.
Again, that is your *presumption*. If you ever get around to actually *testing* that presumption against reality, do feel free to get back to us.
It does not need to be explained away or falsifiable to be scientific.
It most certainly does.
It only begs the question of those who would attribute organized matter to some other cause. What is it?
Matter organizes itself through known, understood natural processes, including (for things which replicate) evolution.
For example, the organization in a snowflake arises due to the basic simple properties of water molecules. There doesn't need to be a deity manually assembling every snowflake personally in order to get it to end up in an organized shape. That happens naturally and in an unguided fashion due to the simple basic interactions of water molecules.
Order and complexity *does* arise due to natural causes. In the case of evolutionary processes, the amount of order and complexity can rise to astounding levels.
This alone cuts the legs out from under the "ID implication" -- the presumption that if something is ordered or complex, then there "must" be a designer at work.
That's not to say that we might not someday find something in nature that *was* the result of a designer twiddling things, but the point is that the IDers "must" presumption comes crashing down when it is pointed out that order and complexity *can* and *do* often arise through natural processes. Consequently, you can *not* make a conclusion (or even presumption) that finding ordered or complex things "automatically" demonstrates the existence of a designer. It doesn't, since those ordered or complex things may well be yet more examples of naturally-occurring order, *even* if we have not yet determined if or how those particular things came about naturally.
Because any given ordered/complex thing we find in nature *could* possibly have arisen naturally -- in the same way that a snowflake and a zillion other things are known to do -- it is a *fallacy* to conclude that any/all complexity in nature *has* to be the work of a designer. Futhermore, it is even fallacious to conclude that any/all natural order *implies* a designer.
Because you're (well, not "you," necessarily) would the only one who would make such a claim in the first place. The "interfering deity" would have to be advanced as an explanation for why a "negative result" does not support Behe's claim.
could you discount the proposition that the Designer dunnit? You cannot, because ID is not science. By the very nature of its claims it is unfalsifiable.
You've got to be somewhat embarrassed by this line of thought. It's generally filed under "grasping at straws."
because ID is not science. By the very nature of its claims it is unfalsifiable.
Try telling that to the biotech guys.
Genetic engineers are not inventers. They are just cutting and pasting from one document to another. The inventing was done by evolution.
Since ID claims that the interfering designer exists, it can scarcely complain when the interfering deity is used as a counter-argument.
You've got to be somewhat embarrassed by this line of thought. It's generally filed under "grasping at straws."
Complete lack of any counter-argument noted. Who is grasping at straws?
Try telling that to the biotech guys.
False and irrelevant conflation of intelligent design as performed by humans and the pseudo-scientific hypothesis of ID noted. I think this has gone far enough. I suspect that the lurkers can see quite clearly who is clutching at straws.
Why isn't Krebs Cycle cited as an example of IC?
They are the ones who declare ID to be "unscientific" merely because it implies a Creator.
No, they call it unscientific because it doesn't conform to the basic standards of science. Funny how we insist on standards, huh?
They are the ones who would exclude inferences, implications, possibilities, hunches, and the like as being "unscientific."
Kindly cite one example of this canard.
Scientists don't discount hunches. On the contrary, they rely on hunches. What they don't accept is the notion that hunches are a substitute for scientific evidence. But then we're back to those pesky standards.
This is just more of the affirmative action whining. You can't create a coherent theory to support ID, so you want to lower scientific standards to your level.
That's a cop out, too. Science doesn't do that. Science has ways of knowing. Science is not in the business of telling itself what it cannot do, or what it cannot explore. Most reasonable people, however, would rule out "the flatulence of a Cosmic Deity" as a source or cause behind organized matter, dontcha think?
That presumably includes instances where one might attempt to constrain the putative designer to only inscrutable motives and methods....
If you want to place constraints on the designer then you'd better say what they are and why you've chosen those constraints, then we'll be able to judge if the designer may have been fiddling with our experiments.
One may approach this by the simple expedient of pointing out that we humans have the ability to understand (at some level) many of the processes of nature. As applied to ID, one could point out that we understand the practical purposes satisfied by various traits and phenomena. Furthermore, they are similar to the optimization approaches that we, ourselves, apply. The fact that we can understand these things directly, in terms of their practical applications, would argue strongly against the idea of inscrutability on the part of the hypothesized designer.
Very true and absolutely nothing to do with ID.
Recall that the comment was made in response to your claim that a designer must be completely inscrutable. But because inscrutability is not a necessary condition for a designer (for example, humans designers don't meet this standard), pointing to the "scrutablility" of what we see around us has quite a bit to do with ID, particularly in dismissing your attempt to impose inscrutability.
It most certainly is.
Tonight, at 11:00.
"Science has ways of knowing"
Are you a glottun for punishment?
That would be TESTING now wouldn't it.
This has been one FUN thread to watch develop.
So tell us what ID hypothesizes about the designer.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.