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)
Well, according to the Book:
John 3:17-19
17 For God did not send his Son into the world to condemn the world, but to save the world through him.
18 Whoever believes in him is not condemned, but whoever does not believe stands condemned already because he has not believed in the name of God's one and only Son.
19 This is the verdict: Light has come into the world, but men loved darkness instead of light because their deeds were evil.
|
;^)
The BigBang 'theory' re-arranges it:
M=E/C2
Then the question becomes:
"Where did the Energy come from?
You'll not win at TicTacToe with this stradegy!
A cubic inch of water consists of organized physical matter. It is quantifiable, predictable, physical, palpable, much like any designed obect. It also happens to behave purposefully, like any designed object.
I think I get it now. You infer from the presence of physics that there's a designer?
Bizarre logic, but at least I understand now why you can't actually cite any physical evidence for your "designer" if that's the best you can come up with.
Inferences from indirect evidence are part of science.
Note to Self: Get Peer Review before posting.
The upshot is that the effective mass increases as the speed increases.
1. I can't imagine how P could possibly be false
2. Therefore, P.
A simple variation on this is
1. I cannot imagine how P could possibly be true
2. Therefore, not-P.
That pretty much sums up arguments against intelligent design. "It's not scientific."
Your blather is woefully transparent.
Are you saying physics consists of no physical evidence to support it? Talk about "bizzare" logic!
I'm still waiting to hear your scientific alternative to intelligent design as causative of organized matter.
You can't even provide us a definition of design, how the hell do you expect anybody to take you seriously? You think that logical fallacies are compatible with science. You think that your feelings don't need to be tested. You are a mystic. Why don't you jut admit that and stop trying to pretend you are being scientific? And now, for the umpteenth time, what is design? What is science?
Inferences from indirect evidence are part of science.
Yes, but they are the beginning of science.
Eventually, you need to be able to find some actual physical evidence. You need to be able to formulate a scientific theory. ID hasn't been able to do either.
Are you saying physics consists of no physical evidence to support it? Talk about "bizzare" logic!
No, I'm saying that calling the existence of physics physical evidence for the existence of a creator is bizarre.
And I stand by that. It's a huge leap. Moreover, it's a cop-out. More of the "goddidit" fluff that we've seen so often, guesswork as the end of science instead of its beginning.
Intelligent design is not a theory. It is the foundation of all science. You have not offered, and cannot offer, any alternative.
"Intelligent design is not a theory."
I agree.
I've used terminology related to design and how it applies in this case. It escapes you, most likely out of willful ignorance.
Design entails the arrangement of matter in such a way as to be organized and purposeful. Atoms do not fly apart because they are designed to retain their respective pattern of form and behavior. If design is not responsible for atoms retaining their form, then what, scientifically speaking, is?
I said nothing about the origins of matter. I am discussing the ability of matter to retain its consistency and transmit information.
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