Re: Article: Scientists propose the kind of chemistry that led to


"Graham Jones" <x@xxx> wrote in message news:f4mn78$1eel$1@xxxxxxxxxxxxxxxxxxxxxx

"Perplexed in Peoria" <jimmenegay@xxxxxxxxxxxxx> wrote in message
news:f4k34t$560$1@xxxxxxxxxxxxxxxxxxxxxx

"Tim Tyler" <seemysig@xxxxxxxxxxxxxx> wrote in message
news:f4indn$2ivt$1@xxxxxxxxxxxxxxxxxxxxxx
This appears to be:

"Stochastic innovation as a mechanism by which catalysts might
self-assemble into chemical reaction networks"

Justin A. Bradford and Ken A. Dill

http://www.pnas.org/cgi/content/abstract/0703522104v1

AFAICT, it's Eigen's hypercycles - as popularised
by Kauffman as autocatalytic sets - all over again.

AFAICT, it is not even that coherent. I haven't read the paper, but
this bit from the press-release does not instill confidence:

In its simplest form, ... The process could go like this:
Catalyst A produces a chemical that catalyst B uses. Now, since B normally
seeks out this chemical, sometimes B will be attracted to A -- if its
desired chemical is not otherwise available nearby. As a result, A and B
will come into proximity, forming a complex.

Catalyst B normally 'seeks out' its substrate? Wow. That is one smart,
well motivated molecule!

One hopes this was metaphor. But metaphor for what??!!


If B binds to its substrate, the concentration of unattached B goes down
near high concentrations of A and diffusion restores it.

Diffusion of the catalyst B, not diffusion of the substrate molecule!

As far as I can
tell, that is the basic content of the paper, which is available for free at
http://www.dillgroup.ucsf.edu/

Thx.

In their computer model, all the reactions happen on a 2D surface in a 3D
liquid. I am not clear what difference that makes.

That is how they slow down the diffusion of the substrate. It is constrained
to 2D, but the catalyst B can hop around in 3D.

Overall, I have to say this is the most absurd paper I have read on the
origin of life, and I have read some pretty silly ones.


.

Relevant Pages