Origins of life is a tricky business. We can’t know how it happened. We weren’t there and chemical reactions and molecules just don’t fossilize well. The point is not to show how it happened. Likewise, the point is not (necessarily) to create a new form of life in the lab. The point is to show that chemistry and physics alone can plausibly create life.
If it can be shown that there are no physical or chemical barriers to the generation of life from non-life, then there is no need for intelligent design.
This is the third installment of my survey of origins of life research. The fourth (future) post is planned to discuss early replication. The previous posts covered the odds of chemical systems becoming life (for some value of ‘life’) and the ability of nucleobases spontaneously self assemble.
That last bit got to wondering about the actual self assembly and how it works. First, I have to say that there are many models of how this happened. Some work in the mid 90s showed how long chain RNAs could self assemble on clay substrates.  That was the original article that I was going to write this post about. One main reason is that creationists can’t complain that long chain RNAs can’t self assemble. It’s been shown it can be done since around the time that Behe’s Darwin’s Black Box was published.
However, while researching this post I came across a more recent, and to me, more exciting paper. Forget all the minerals and catalysts and exotic conditions others have proposed. According to the authors of this paper, Darwin may well have been correct with life developing in his small, warm pond.
From the authors:
A key step missing in the reconstruction of the origin of living systems is an abiotically plausible synthesis of RNA. To fill this gap, for the robust synthesis and the simultaneous presence of all the necessary nucleic acid precursors (which is possible in principle (22)), an abiotic procedure for their activation and a thermodynamically sound polymerization mechanism are needed.
This paper takes care of the thermodynamically sound polymerization step. Now, I freely admit that this paper uses cyclic nucleotides, but that is not an insurmountable obstacle [2,3,4,5].
So, the authors examined low concentrations (as low as 1 micromol) of cyclic nucleosides in a large variety of conditions to look for evidence of long chain polymerization. The results are stunning. Of all the conditions tested (pH differences, presence of minerals, concentrations, etc) the best results came simply from warm water (40°C to 90°C).
Open nucleotides (not cyclic) don’t polymerize in warm water and often degrade under those conditions. Cyclic nucleotides, on the other hand, formed polymers. The various nucleotides were tested (A, C, G, U).
The simplest tests resulted in up to a 25 nucleotide chain. Further (referencing the “What are the Odds post”), the chains formed fast. An average result was an 11 nucleotide chain forming in less than a minute. By letting the reactions continue for over 100 hours, molecules larger than 100 nucleotides were formed. In nothing but warm water.
Further, the authors analyzed the actual chemical bonds to make sure that this was ‘our modern’ RNA being formed. It was, the normal 3’-5’ phosphodiester bonds were formed.
So, here we have what is effectively modern RNA chains being formed from prebiotic precursor molecules in nothing more than warm water. It happens quickly and the results are stable.
In my reviews so far, we have the simple fact that very small RNAs can be used as catalysts. We have the production of RNAs from precursor materials. And here, we have a completely different method for the production of long chain RNAs.
I think that last bit is very important. There isn’t just one method that will work, there are at least two, and probably more, chemically feasible methods of getting from base, inorganic precursors all the way to RNA.
And it could have happened, just like Charles Darwin predicted over 150 years ago.
Costanzo, G., Pino, S., Ciciriello, F., & Di Mauro, E. (2009). Generation of Long RNA Chains in Water Journal of Biological Chemistry, 284 (48), 33206-33216 DOI: 10.1074/jbc.M109.041905
 James P. Ferris, et. al, “Synthesis of long prebiotic oligomers on mineral surfaces”, Nature, Vol. 381, 2 May 1996, pp. 59-61.
 Costanzo, G., Saladino, R., Crestini, C., Ciciriello, F., and Di Mauro, E. (2007) J. Biol. Chem. 282, 16729–16735
 Saladino, R., Crestini, C., Ciciriello, F., Costanzo, G., and Di Mauro, E. (2007) Chem. Biodiv. Helv. Chim. Acta, 4, 694–720
 Saladino, R., Ciambecchini, U., Crestini, C., Costanzo, G., Negri, R., and Di Mauro, E. (2003) ChemBioChem 4, 514–521
 Saladino, R., Crestini, C., Ciciriello, F., Pino, S., Costanzo, G., and Di Mauro, E. (2009) Res. Microbiol., doi:10.1016/j.resmic. 2009.06.001