Theoretical origin of life: RNA world can't work (Introduction)

by David Turell , Saturday, January 02, 2021, 15:44 (1421 days ago) @ David Turell

Where are the necessary enzymes?:

https://www.popularmechanics.com/science/a35084871/rna-world-hypothesis-origins-of-life...

"Here’s the problem with the RNA-only model (also known as the "RNA world hypothesis"), stated at its most succinct: RNA is too “sticky.”

"That means that, like hydrogen for example, RNA bonds and will not detach from other molecules. In evolutionarily modern times, we know RNA is split from its fresh copies by enzymes, but enzymes arose after RNA. How did the first RNA strands come unstuck without help?

"For primordial molecular strands of DNA and RNA, chimerism takes the form of single strands with evidence of both kinds of genetic information. That means reducing the “stickiness” of RNA alone and creating a path that explains original RNA replication without enzymes. It’s like those popsicles with two sticks: holding the sticks gives you leverage to snap apart the double popsicle.

***

"if RNA managed to unstick itself without enzyme help, that could have implications for the same mRNA that’s in the news in 2020. Enzymes are fragile, researchers say, meaning that in any given supply chain that results in mRNA for consumption, the enzymes are often the weakest link.

"Scientists may be able to model future RNA synthesis on an original, chimeric process that doesn’t require enzymes at all. With fewer moving parts and less vulnerability, that could mean more robust products that can travel further, last longer, and endure a wider variety of conditions—even vaccines."

Comment: The article presents the huge known problem: enzyme molecules are enormous and very specific in shape and content of amino acids. Where did they come from on early Earth?