Abiogenesis: Hypothetical Origins of Life - The Real Enemy of Creationism, page 2

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reply posted on 2-12-2008 @ 10:17 PM by Rren

ScienceDaily.com

Possible Mechanism For Creating 'Handedness' In Biological Molecules

Scientists at the U.S. Department of Energy's Argonne National Laboratory have discovered a way to induce this handedness in pre-biological molecules.

"Understanding how the molecules necessary for life originated is one of the most basic scientific questions in biochemistry," Argonne chemist Richard Rosenberg said. "Chirality plays a fundamental role in biological processes and researchers have been trying to discover the mechanisms that led to this property for years."

Rosenberg used X-rays from the Advanced Photon Source to bombard chiral molecules adsorbed on a magnetic substrate and x-ray photoelectron spectroscopy to track changes in the molecular bonds.

He found that changing the magnetization direction in relation to the high-intensity X-ray beam created an excess of one chirality over another. Changing the magnetization direction reverses the spin polarization of the secondary, or low-energy, electrons emitted from the substance.

Iron is a common element and is magnetic in many form and ionizing radiation and magnetic fields are prevalent throughout the universe.

Based on the Argonne results, it is conceivable that chirality could have been introduced by irradiation of molecules as they traveled through the universe while adsorbed on a magnetized substrate in a dust cloud, meteor, comet or on a primitive planet.

"Our study shows that spin-polarized secondary electrons interacting with chiral molecules could produce a significant excess of a given chirality in pre-biological molecules," Rosenberg said.

A paper on Rosenberg's work can be seen in a recent issue of Physical Review Letters.

Please visit the link provided for the complete story.

The paper can be found through here: Chiral-selective chemistry induced by spin-polarized secondary electrons from a magnetic substrate

Abstract:

Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, USA.

We demonstrate for the first time that low-energy spin-polarized secondary electrons, produced by irradiation of a magnetic substrate, can induce chiral-selective chemistry. Our approach was to perform detailed measurements of the reaction rate for x-ray induced, secondary electron photolysis of a model chiral compound, (R)- or (S)-2-butanol, adsorbed on a magnetized Permalloy substrate. The results showed that there is an enhancement of approximately 10% in the rate of CO bond cleavage that depends on the chirality of the molecule and the spin polarization of the substrate secondary electrons.

PMID: 18999792 [PubMed - in process]

Not sure if you're still around Zip, or still following this stuff... Just an FYI for you or anyone else whom might be interested.

reply posted on 4-12-2008 @ 11:58 AM by noobfun

reply to post by Rren

great find Rren

it goes a long way to upset bith the handed and radiation falsehoods presented on page 1

neither destroys the possability of life as stated, 1 helps create the other to promote essentail conditions

its should be one less play to play peek-a-boo with the god of the gaps, but will probabily just get ignored

reply posted on 4-12-2008 @ 01:55 PM by Rren

Originally posted by noobfun
reply to post by Rren

great find Rren

it goes a long way to upset bith the handed and radiation falsehoods presented on page 1

I don't really see any falsehoods presented on the first page here. There was a mention of the observation of 'handedness' with respect to the Miller Urey experiment which was just that,... an observation of the results. The idea that a specified handedness could not be a result of chance (which wasn't really given much ink here) was supported by the link Zipdot posted which said that the handedness was most likely the result of a selection process(1) and/or the effects of space(2). This new research adds support to the latter, but there is still quite a ways to go. The argument was that there needs to be some sort of mechanism responsible because a 'chance assemblage of parts' was too improbable. Now it looks like we have a possible mechanism... perhaps (later?) coupled with some sort of a replication mechanism and selection process you have the makings of abiogenesis. Perhaps a sort of panspermia-lite.

I typically like to wait for the experts to start looking at and debating the merits and importance of new findings. Not being an astrophysicist or biochemist/biophysicist (etc) I can't really form my own opinion yet. It's a long way from a possible mechanism which can explain handedness to life. However, I am very interested to see where this goes... but I haven't noticed a whole lot of buzz about this in the usual places yet. We shall see.

neither destroys the possability of life as stated, 1 helps create the other to promote essentail conditions

Not sure I follow.

its should be one less play to play peek-a-boo with the god of the gaps, but will probabily just get ignored

Around ATS? Most probably. This thread is pretty old. There used to be quite a few members (some scientists) whom followed/discussed/debated this stuff a couple years ago. I think most (myself included) got tired of the same-old arguments so stopped contributing. Most of those guys are not even around ATS anymore. Zipdot was the FSME for this forum and I haven't seen him in ages.

In the scientific community? I doubt, assuming it is as important as it looks, this will be ignored. By 'either' side I'd wager. However, re: gaps, whomever was arguing that chance was insufficient and that there can be no possible mechanism to account for handedness just lost their gap. Like I said, it should be interesting to see what if anything comes from this.

Some folks will have to do some tap-dancing. Others will just incorporate this new data into their models (it is not too earth-shattering) and move on. Same as it ever was. *shrug*

Regards.

reply posted on 4-12-2008 @ 02:17 PM by Nohup

I personally tend to think that life, along with the rest of the universe, exists in a temporal loop made possible by the permeability of spacetime. That is, time and space are by no means linear, and bits and pieces of it are continuously shifting back and forth, in and out of the past, present and future.

I suspect (since it would be impossible to prove), that every now and then the natural fluctuations of spacetime trap little bits of living material in what would basically be "subspace" bubbles, and throw them off randomly into different places and times. Once in a rare while, these things manage to land on or near a habitable planet, and then evolution is off to the races.

Anyway, what this little notion does is remove from the equation the requirement for there to be a conscious, intelligent entity of some sort guiding the genesis. It creates a problem for the Creationists, who hope to use the concept of "God" as a default explanation for the existence of life. If you eliminate from the argument some basic assumptions about space and time, there are other ways it could have happened.

[edit on 4-12-2008 by Nohup]

reply posted on 4-12-2008 @ 03:15 PM by Rren

Originally posted by Nohup
I personally tend to think that life, along with the rest of the universe, exists in a temporal loop made possible by the permeability of spacetime. That is, time and space are by no means linear, and bits and pieces of it are continuously shifting back and forth, in and out of the past, present and future.

I suspect (since it would be impossible to prove), that every now and then the natural fluctuations of spacetime trap little bits of living material in what would basically be "subspace" bubbles, and throw them off randomly into different places and times. Once in a rare while, these things manage to land on or near a habitable planet, and then evolution is off to the races.

This works for the really small (quantum) stuff:

(Wiki)Action at a distance (physics): "is the interaction of two objects which are separated in space with no known mediator of the interaction."

(Wiki)Quantum entaglement: " is a quantum mechanical phenomenon in which the quantum states of two or more objects are linked together so that one object can no longer be adequately described without full mention of its counterpart — even though the individual objects may be spatially separated."

Now if you couple those 'facts' or observations with Penrose and Hameroff's Orchestrated Objective Reduction (Orch_OR) Theory of Consciousness[ToC] you get:

(Wiki) Orch_OR
Penrose postulates that each quantum superposition (possible position of the particle) has its own piece of spacetime curvature. According to his theory, these different bits of spacetime curvature are separated from one another, and constitute a form of blister in spacetime. Penrose further proposes a limit to the size of this spacetime blister. This is the tiny Planck scale of (10−35 m). Above this size, Penrose suggests that spacetime can be viewed as continuous, and that gravity starts to exert its force on the spacetime blister. This is suggested to become unstable above the Planck scale, and to collapse so as to choose just one of the possible locations for the particle. Penrose calls this event objective reduction (OR), reduction being another word for wave function collapse.

Which sounds very much like what you said... except...

Nohup:

Anyway, what this little notion does is remove from the equation the requirement for there to be a conscious, intelligent entity of some sort guiding the genesis. It creates a problem for the Creationists, who hope to use the concept of "God" as a default explanation for the existence of life.

it is hypothesized in ToC that:

Orch_OR(abstract):

Unlike the random, "subjective reduction"(SR, or R) of standard quantum theory caused by observation or environmental entanglement, the OR we propose in microtubules is a self-collapse and it results in particular patterns of microtubule-tubulin conformational states that regulate neuronal activities including synaptic functions. Possibilities and probabilities for post-reduction tubulin states are influenced by factors including attachments of microtubule-associated proteins (MAPs) acting as "nodes"which tune and "orchestrate"the quantum oscillations. We thus term the self-tuning OR process in microtubules "orchestrated objective reduction"("B>Orch OR", and calculate an estimate for the number of tubulins (and neurons) whose coherence for relevant time periods (e.g. 500 milliseconds) will elicit Orch OR. In providing a connection among 1) pre-conscious to conscious transition, 2) fundamental space-time notions, 3) non-computability, and 4) binding of various (time scale and spatial) reductions into an instantaneous event ("conscious now", we believe Orch OR in brain microtubules is the most specific and plausible model for consciousness yet proposed.

Couple that with the idea that consciouness is required to collapse the wave function and you, once again, have your "requirement for there to be a conscious, intelligent entity of some sort guiding the genesis." Either way, 'handedness' doesn't change this stuff any. Or, if it does, I am too ignorant of the nuances to say how or where it effects it.

If you have never heard of Orch_OR before now, Hameroff has a corrolary to that which asks Did Consciousness Cause the Cambrian Evolutionary Explosion? which is pretty interesting and thought provoking in of itself (his work and papers can be found through this site also):

Conclusion

The place of consciousness in evolution is unknown, but the actual course of evolution itself may offer a clue. Fossil records indicate that animal species as we know them today including conscious humans all arose from a burst of evolutionary activity some 540 million years ago (the "Cambrian explosion"). It is suggested here that:

1. Occurrence of consciousness was likely to have accelerated the course of evolution.

2. Small worms, urchins and comparable creatures reached critical biological complexity for emergence of primitive consciousness at the early Cambrian period 540 million years ago.

3. Cooperative dynamics of microtubules, cilia, centrioles and axonemes were the critical biological factors for consciousness.

4. Cytoskeletal complexity available in early Cambrian animals closely matches criteria for the Penrose-Hameroff Orch OR model of consciousness.

5. Orch OR caused the Cambrian explosion.