Interesting Science Daily article: http://www.sciencedaily.com/releases/2013/09/130913185848.htm

They indicate these researchers have found ‘Molecular Fossils’. Uh, whatever. Not fossils.

The molecules found are believed to be very primitive. That is, rudimentary and possibly about the same as the first self-replicating chemicals on earth. Lots of assumptions here.

The article should provide plenty for those who wish to fight biological evolution. Of course, this is how science works. You look at it, figure out what is wrong with it, and try something else. These researchers seem to be finding significantly more than we’ve known before, and they say there is even more to figure out. 

The article is essentially copied from UNC, here, http://news.unchealthcare.org/news/2013/september/carter, where they include the good Professor’s yearbook photo.

The paper is here: http://www.jbc.org/content/288/37/26856, but paywalled. They are way too proud of it.

This probably makes the necessary point well enough (quoting):

Capsule

Background: RNA World scenarios require high initial fidelity, greatly slowing lift-off.

Results: Class I TrpRS and Class II HisRS Urzymes (120–130 residues) both acylate tRNAs ∼106 times faster than the uncatalyzed peptide synthesis rate.

Conclusion: Urzymes appear highly evolved, implying that they had even simpler ancestors.

Significance: High Urzyme catalytic proficiencies imply that translation began in a Peptide·RNA World.

–End quote–

Also from the link to the paper:

“Abstract

We describe experimental evidence that ancestral peptide catalysts substantially accelerated development of genetic coding. Structurally invariant 120–130-residue Urzymes (Ur = primitive plus enzyme) derived from Class I and Class II aminoacyl-tRNA synthetases (aaRSs) acylate tRNA far faster than the uncatalyzed rate of nonribosomal peptide bond formation from activated amino acids. These new data allow us to demonstrate statistically indistinguishable catalytic profiles for Class I and II aaRSs in both amino acid activation and tRNA acylation, over a time period extending to well before the assembly of full-length enzymes and even further before the Last Universal Common Ancestor. Both Urzymes also exhibit ∼60% of the contemporary catalytic proficiencies. Moreover, they are linked by ancestral sense/antisense genetic coding, and their evident modularities suggest descent from even simpler ancestral pairs also coded by opposite strands of the same gene. Thus, aaRS Urzymes substantially pre-date modern aaRS but are, nevertheless, highly evolved. Their unexpectedly advanced catalytic repertoires, sense/antisense coding, and ancestral modularities imply considerable prior protein-tRNA co-evolution. Further, unlike ribozymes that motivated the RNA World hypothesis, Class I and II Urzyme·tRNA pairs represent consensus ancestral forms sufficient for codon-directed synthesis of nonrandom peptides. By tracing aaRS catalytic activities back to simpler ancestral peptides, we demonstrate key steps for a simpler and hence more probable peptide·RNA development of rapid coding systems matching amino acids with anticodon trinucleotides.”

So, got it? It is good to stretch, right? I think so.

For me, the bottom line is that there do seem to be ways for life to have kick-started itself right here on this planet the way God made it without special intervention. Rather than rage against nature and natural ways to explain things, I think it more productive to just keep seeking truth and just keep checking and experimenting and explaining.

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