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)
Whatever emotional inferences I make, or anyone else makes for that matter, emanate from the Supreme One - God.
That's fine. You may of course believe whatever you choose.
Just don't pretend that chosen belief is physical evidence, and I have no quarrel with you.
Do you really believe that your feelings are physical evidence?
Not exactly "synonymous," not exactly coterminous either, but "inherent in." That is to say, every designed object has regularity and order. Where we find regularity and order, therefore, it is not necessarily unreasonable, or unscientific, to infer design.
Most of Western science has begun with the assumption that God created the heavens and the earth and still sustains them. It is a sound working assumption. It is no surprise that science is chock-full of evidences to show an intelligent designer was, and is, involved with the creation. The information contained in a single strand of DNA is just one small case in point.
Oh my God. I didn't check out his homepage.
"Breaking down the sexual barriers between the races is a major weapon of cultural destruction because it means the dissolution of the cultural boundaries that define breeding and the family and, ultimately, the transmission and survival of the culture itself."
That's disgusting.
"That is to say, every designed object has regularity and order."
So every time you see regularity and order, you see design. How wonderfully tautological.
"Most of Western science has begun with the assumption that God created the heavens and the earth and still sustains them. "
NO scientific theory incorporates the supernatural. Not one.
Look at the origin of the quote, it was in this article:
http://www.vdare.com/asp/printPage.asp?url=http://www.vdare.com/francis/041126_football.htm
Very revealing.
Yes, design is self-evident in more ways than one.
It just gets more and more disgusting.
You have stated that absolutely everything of 'order' (a slippery term at best), from the laws of physics to a cube of water shows evidence of design. More than that you have repeatedly confirmed that the designer is and can only be the Christian God.
Science is not just something people do, it is a methodology, a set of logical steps based on the same principles as formal critical thinking, an algorithm that has developed over time to enable us to determine with a level of certainty beyond what previous methods, or lack of methods, gave us, accurate knowledge of our natural surroundings. A major part of that certainty comes from our ability to devise and perform tests that rely heavily on the consistency we can expect from our natural surroundings; that consistency which we describe mathematically and label 'law'.
You have created a universe where everything and anything that can be construed as having 'order' is evidence of a designer, a designer that you have given the power to not only 'create' irrespective of the laws of physics but can also interfere at will with the observation, investigation and testing of all phenomena.
There is no way to conclusively know that this designer is or is not interfering with a given test. Since the scientific method was developed to give us some level of certainty beyond what simple observation gives us, anything that decreases that certainty will also decrease the benefit of using the scientific method and may take us back to the level of uncertainty we had before the development of the scientific method. In this case, science becomes meaningless.
Because you desire the universe to not only be designed, but designed by your specific God, and I believe you understand the difficulty a designer that is essentially above physical laws introduces to, and in fact invalidates, the scientific method, you have broadened the definition of science to be simply observation by a human. This enables you to say, without evidence I must add, that any putative 'order' in the universe is evidence of a non-human designer, going so far as to implicitly equate order with design. Your redefinition of science and consequently the scientific method has made the term 'science' and the use of the scientific method meaningless.
Interestingly, if you insist that the designer of the universe can be tested for because he/she/it will not and has not interfered with the consistency of physical laws, then you have to accept the age of the universe, the age of the earth, the fossil record and all of evolution, all of which rely on the 'unchanging' universe.
DogDidit placemark
We would know the car as a 'designed', and more importantly 'manufactured' object because we would notice the similarity of patterns, materials, form, manufacturing methods (tool marks) and the lack of 'apparent' randomness we see in nature, to other artifacts we have observed humans creating. This does not mean we can determine the designedness of nonhuman creations.
Your analogy of a car in a desert is inaccurate. The design you stipulate is inherent in DNA, a cube of water, or any other phenomenon we do not create can not be determined in the same way we determine design in human created artifacts. Because of the possibility of nonhuman designers, we need to design a more rigorous method that can be used without any knowledge of the designer. So far this has not been developed.
No, the physical evidence continues to reveal 'order' and regularity from which our primate brains discern patterns. You claim - nothing but a bald assertion - that this is because of design. We claim it is because of the physical attributes of the universe. By the way, 'laws' are nothing but descriptions of the observation of highly consistent phenomena.
Who would disagree with that? It appears you don't understand the focus of the discussion. The problem is not in inferring a designer from something that is demonstrably designed, but in determining what is and is not truly designed. Please address the correct problem.
Your suggestion of this shows you have no idea how we differentiate between human designed and manufactured objects, and naturally occurring objects. It also shows a lack of knowledge about aboriginals.
No one forced you to take it down, anymore than people forced you to put it up.
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