"Further reading shows major problems with the “RNA World” hypothesis these days, in spite of decades of hype about the insight it had provided. Krishnamurthry (lets call him RK) knocks Miller’s spark-discharge icon while he’s at it.
Amino acids are not rare. Life uses only twenty types, all left-handed, out of hundreds of amino acids. RNA and DNA are much more complicated molecules. Their formation goes against the natural laws of chemistry. Szostak, a leading past proponent of the RNA World hypothesis, knows that.
Further pained reading of this doomed article shows RK struggling to find “selection” in prebiotic chemistry that might lead not to life, but to “proto-biochemistry”.
Then we learn that progress is all in futureware:
--blind,
--deaf,
--and has nowhere to go.
That’s a random walk."
CEH
In the beginning God created.... Genesis 1:1
Miller, we recall, only could say ‘Voila!‘ about tiny amounts of four amino acids, all mixed-handed.The RNA world has, however, come in for much criticism lately, which Krishnamurthy believes is deserved. RNA is able to transfer genetic information in organisms and is made of chains of ribonucleotides. But there’s a catch.
“Nucleotides don’t just pop up from chemical mixtures, they have to be made in a very defined manner,” he says. “There has to be a certain order to the reaction sequence. It’s not like Stanley Miller’s spark discharge experiment where he put all these gases together, pressed a switch and ‘Voila!‘”
Amino acids are not rare. Life uses only twenty types, all left-handed, out of hundreds of amino acids. RNA and DNA are much more complicated molecules. Their formation goes against the natural laws of chemistry. Szostak, a leading past proponent of the RNA World hypothesis, knows that.
Although Szostak agrees that systems chemistry has the power to support the RNA world theory, or at least explain the origin of RNA, he points out that a disproportionate amount of work has been put into understanding how nucleotides form, and not enough into what happens after that. “There are still missing steps in understanding how RNA could be made,” he says. So, the challenge now for systems chemistry is to show how and why each of these stages occur.
“Just synthesizing a monomer of RNA like a nucleoside or a nucleotide isn’t enough to say you’ve found the origin of RNA,” says Krishnamurthy. “How do you put those monomers together in a meaningful manner that is self-sustainable?”
Further pained reading of this doomed article shows RK struggling to find “selection” in prebiotic chemistry that might lead not to life, but to “proto-biochemistry”.
Then we learn that progress is all in futureware:
There is a long way to go yet and Krishnamurthy recommends that progress will be best made with baby steps as scientists develop this bottom-up approach to the origin of life from the heterogeneous prebiotic clutter. By discovering reactions and catalysis that select the right interactions between organic compounds, the aim is to build up our understanding of how the basic building blocks assembled — how, for example, RNA emerged from the chaos.Baby steps are useless if the baby is
--blind,
--deaf,
--and has nowhere to go.
That’s a random walk."
CEH
In the beginning God created.... Genesis 1:1
