Re: Article: In Search of the Simplest Cell

From: Perplexed in Peoria (jimmenegay_at_sbcglobal.net)
Date: 03/28/05 

Date: Mon, 28 Mar 2005 16:36:52 -0500 (EST)

"Robert Karl Stonjek" <rstonjek@bigpond.net.au> wrote in message news:d27cdc$e8o$1@darwin.ediacara.org...
> ORIGIN OF LIFE: IN SEARCH OF THE SIMPLEST CELL
>
> The following points are made by Eörs Szathmary (Nature 2005 433:469):
>
> 1) In investigating the origin of life and the simplest possible life forms,
> one needs to enquire about the composition and working of a minimal cell
> that has some form of metabolism, genetic replication from a template, and
> boundary (membrane) production.
>
> 2) Identifying the necessary and sufficient features of life has a long
> tradition in theoretical biology. But living systems are products of
> evolution, and an answer in very general terms, even if possible, is likely
> to remain purely phenomenological. Going deeper into mechanisms means having
> to account for the organization of various processes, and such organization
> has been realized in several different ways by evolution. Eukaryotic cells
> (such as those from which we are made) are much more complicated than
> prokaryotes (such as bacteria), and eukaryotes harbor organelles that were
> once free-living bacteria. A further complication is that multicellular
> organisms consist of building blocks -- cells -- that are also alive. So
> aiming for a general model of all kinds of living beings would be fruitless;
> instead, such models have to be tied to particular levels of biological
> organization.
>
> Full Text at Science Week
> http://scienceweek.com/2005/sw050325-1.htm

Further down in the referenced web page, I found some comments by Steen
Rasmussen that were more interesting than Szathmary's. That led me to
a long, but interesting, paper by Rasmussen et. al. here:

http://www.ees.lanl.gov/EES5/staff/steen/papers/269-316.pdf

While this paper discusses chemical A-life, and does not necessarily
tell us anything about the historical origin of life on earth, it does
contain some useful thermodynamic analysis of membrane-related dynamic
processes. I is worth glancing at if you are interested in my series
of OOL postings or in lipid-oriented approaches to OOL in general.

First time I have ever recommended a paper originating in Los Alamos!
Perhaps the Stuart Kauffman effect (suppressing the critical intelligence
of anything that comes in contact with him) is not operating in this case.

Relevant Pages