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)
Yes, all of the above are organized according to the chemical properties with which they have been imbued since the beginning, and they behave according to the physical laws which God established in the beginning except in those instances He decides to intervene.
Science, just as in this case, will continually uncover a universe that demonstrates design and order. That's a prediction.
Who said that intelligent agents could not organize matter? You are reading things into what others say that just isn't there. ID is not scientific because it does not live up to the criteria of testability and falsification, not because of some inference about ID creating organization.
That's the point.
It's now on the list of possible additions.
Oh? Are you God, then? Are the folks who produce my son's insulin, God? Of course not. Which just goes to show that, with this statement you're imposing an unnecessary layer on the hypothesis, and in so doing you have met the exact standard for building the dreaded "strawman argument."
You make "the biotech guy" do the same as God, they must therefore be as God.
But I don't "make" the biotech guy do anything except what he's doing -- which is intelligent design, sans the supernatural trappings. Which leaves you somewhat short of having made a point.
All this simply drives home the point I've been making all along: your characterization of what and ID hypothesis must include is incorrect.
Would you mind if I told you to butt out?
How can you, a self-professed atheist, say what God will or will not do?
Leave this field for me and others of my ilk. We at least have a Book (of myths, some say) that we quote-mine from.
For example:
2 Peter 3:9
The Lord is not slow in keeping his promise, as some understand slowness. He is patient with you, not wanting anyone to perish, but everyone to come to repentance.
Does those chemical properties include the semi-random chemical alterations in DNA producing different expressed characteristics over long periods of time? Some of which will be more beneficial to the organism than others?
Keep going, Fester! You've almost caught up!
Are you getting dizzy yet?
Too big or too small?
I disagree on two counts. First, there may be a way to test this inference. Second, it is not testability (or falsifibility) that necessarily define what is, or is not scientific.
Meanwhile, I would like to know why, if something is absolutely true in every sense and by its very nature cannot be falsified, then it is by necessity "unscientific."
To me the essential falsification of intelligent design would be the disintegration of all particle matter along with all intelligence capable of observing it. The falsification of intelligent design, therefore, would be the end of science altogether.
"Let God be true, though every man be a liar."
So now you say there's two kinds of ID, the supernatural kind and the kind we all do every day?
Want to rethink "coy" as appropriate?
One would think that Man, with His wisdom, could have come up with a better word for palindrome than that: it otto read the same backwards: doncha think?
If a scientific case can be made for a Prime Mover, then the case for personal revelation is strengthened as the Prime Mover would have the capability of communicating with its creation.
Damn! Now he won't even let you go to hell.
If you spent as much time answering the question as you did dodging it, we'd have finished this conversation already.
History will doubtless bear out minor alterations in the make up of this or that entity. But, from the standpoint of certifiable observation and documentation the biblical paradigm remains sound. The fossil record alone is a remarkably simple, and potent, testimony to the fact of a world-wide deluge as recorded as handed down to us by a prior generation of observers.
No more of that FAITH stuff!
John 20:27-29
27 Then he said to Thomas, "Put your finger here; see my hands. Reach out your hand and put it into my side. Stop doubting and believe."
28 Thomas said to him, "My Lord and my God!"
29 Then Jesus told him, "Because you have seen me, you have believed; blessed are those who have not seen and yet have believed."
Oversimplying, the first law states that energy cannot be destroyed; it converts from one form to another. The second is that order tends to disorder (entropy) in the universe as a whole.
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