Theoretical origin of life; more directed lab work (Introduction)

by David Turell @, Sunday, January 27, 2019, 23:07 (2127 days ago) @ David Turell
edited by David Turell, Sunday, January 27, 2019, 23:19

The usual fake news. By manipulating proteins in the lab they get something that resembles RNA:

https://www.sciencedaily.com/releases/2019/01/190124095112.htm

"The study's resulting polymers were not RNA but could be have been an important intermediate step in the early evolution of RNA. For building blocks, the researchers used base molecules referred to as "proto-nucleobases," highly suspected to be precursors of nucleobases, main components that transport genetic code in today's RNA.

***

"One main suspected proto-nucleobase in this experiment -- and in previous experiments on the possible the evolution of RNA -- was triaminopyrimidine (TAP). Cyanuric acid (CA) was another. The researchers highly suspect TAP and CA were parts of a proto-RNA.

"The chemical bonds that hold together assemblies of the two suspected proto-nucleobases were surprisingly strong but non-covalent, which is akin to connecting two magnets. In RNA the main bonds holding together modern nucleobases are covalent bonds, akin to welding, and enzymes make those bonds in cells today.

***

"The researchers added two more experiments to test how strongly their RNA-like assemblies preferred making one-handed helices.
First, they introduced a smidgeon of compounds similar to TAP and CA, but which had L or D chirality, to nudge the spiraling direction. The whole batch conformed to the chirality of the respective additive, resulting in assemblies twisting in a unified direction as helices do in RNA and DNA today.

***

"Second, they put the sugar compound ribose-5-phosphate together with TAP to more closely emulate the current building blocks of RNA. The ribose fell into place, and the resulting assembly spiraled in a direction dictated by the ribose chirality.

"This molecule easily formed an RNA-like assembly that was surprisingly stable, even though the pieces were only held together by non-covalent bonds," Karunakaran said.

***

"The research also expands a growing body of evidence supporting an unconventional hypothesis by the Center for Chemical Evolution, which dispenses with the need for a narrative that rare cataclysms and unlikely ingredients were necessary to produce life's early building blocks.

"Instead, most biomolecules likely arose in several gradual steps, on quiet, rain-swept dirt flats or lakeshore rocks lapped by waves. Precursor molecules with the right reactivity enabled those steps readily and produced abundant materials for further evolutionary steps."

Comment: This is all directed by human thought. Where did all these exact proteins come from on a rocky Earth? Fun and games and unrealistic expectations whbich support research grants.


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