Speculations on the origin of DNA / RNA

[frankglennjacobs@gmail.com]

If I knew what I'm talking about, I would enlighten the world in a declarative Thread.

 

This is just an old man asking what nobody has explained to me in several generations.

 

[The following are all questions, even tho I didn't put question marks after them.]

 

Speculation A: Some DNA or RNA fell in a meteor and was not incinerated.

(But that just moves the question back a kazillion years to another world.)

 

Speculation B: The world is large. The oceans are wide. Rainwater dissolves just about everything

and flows on down to the sea. Atoms and molecules of just about everything bang

into each other there.

Eventually, at random, something fairly close to DNA/RNA came to pass.

 

Speculation C: In the beginning, after rock had floated up out of the liquid iron core and cooled off

enough so rain could stand on the surface, God hand-made a DNA molecule.

 

Speculation D: (Totally unknown and possibly even unknowable.)

 

Speculation E: From Speculation A, B, C, or D, above, a molecule of DNA with little or no genetic

information replicated itself in immense numbers. Occasional mutations added pairs

of amino acids in random, meaningless, useless sequences. Over hundreds of

millions of years, billions of lifeless random varieties accumulated, doing nothing at all.

 

Much later, a variety happened, among so many, that produced an enzyme that

disassembled (digested!) its neighbors. (Or some other evolutionary advantage.)

 

Then that variety multiplied more than the others did. And the circus was on. Survival

of the fittest! Charles Darwin! Life! Movement! (dim) Intelligence! Sight! Brain!

Self-awareness! Bioluminescence! Poison spines! Camouflage! Pain! Fear!

(somewhat superior) Intelligence! Photosynthesis! Teeth! Low, cunning, hatred!

​ Armor-plating! Bone! Nerves! Air-breathing! Hair! All that mammal stuff!

Edited May 6, 2017 by frankglennjacobs@gmail.com

[Sensei]

Do you heard about Miller-Urey experiment?

https://en.wikipedia.org/wiki/MillerUrey_experiment

 

"After Miller's death in 2007, scientists examining sealed vials preserved from the original experiments were able to show that there were actually well over 20 different amino acids produced in Miller's original experiments. That is considerably more than what Miller originally reported, and more than the 20 that naturally occur in life"

 

"This experiment inspired many others. In 1961, Joan Oró found that the nucleotide base adenine could be made from hydrogen cyanide (HCN) and ammonia in a water solution. His experiment produced a large amount of adenine, the molecules of which were formed from 5 molecules of HCN.[15] Also, many amino acids are formed from HCN and ammonia under these conditions.[16] Experiments conducted later showed that the other RNA and DNA nucleobases could be obtained through simulated prebiotic chemistry with a reducing atmosphere.[17]"

[frankglennjacobs@gmail.com]

About fifty or sixty years ago, an organic chemistry professor (teaching biological chemistry for that day?) told us that it had been shown that under some particular weather conditions many amino acids were spontaneously produced. That seemed important and it stuck with me.

 

I greatly erred in another Thread, thinking that DNA was a protein. It seems amino acids are readily available, but nobody has a clue about how DNA came about. That might be what got serious people thinking maybe DNA came in on a meteor. ("Eliminate the impossible . . . ")

Edited May 7, 2017 by frankglennjacobs@gmail.com

[Moontanman]

About fifty or sixty years ago, an organic chemistry professor (teaching biological chemistry for that day?) told us that it had been shown that under some particular weather conditions many amino acids were spontaneously produced. That seemed important and it stuck with me.

 

I greatly erred in another Thread, thinking that DNA was a protein. It seems amino acids are readily available, but nobody has a clue about how DNA came about. That might be what got serious people thinking maybe DNA came in on a meteor. ("Eliminate the impossible . . . ")

 

 

Here are some good starting points, it must be said that the way you ask the question seems to indicate you have an agenda but I will assume you just want to know.

 

https://en.wikipedia.org/wiki/RNA_world

 

The RNA world hypothesis is supported by many independent lines of evidence, such as the observations that RNA is central to the translation process and that small RNAs can catalyze all of the chemical group and information transfers required for life.^{%5B9%5D%5B11%5D} The structure of the ribosome has been called the "smoking gun," as it showed that the ribosome is a ribozyme, with a central core of RNA and no amino acid side chains within 18 angstroms of the active site where peptide bond formation is catalyzed.^%5B8%5D Many of the most critical components of cells (those that evolve the slowest) are composed mostly or entirely of RNA. Also, many critical cofactors (ATP, Acetyl-CoA, NADH, etc.) are either nucleotides or substances clearly related to them. This would mean that the RNA and nucleotide cofactors in modern cells could be an evolutionary remnant of an RNA-based enzymatic system that preceded the protein-based one seen in all extant life.

 

https://en.wikipedia.org/wiki/Abiogenesis

 

Many approaches to abiogenesis investigate how self-replicating molecules, or their components, came into existence. It is generally thought that current life on Earth is descended from an RNA world,^%5B15%5D although RNA-based life may not have been the first life to have existed.^{%5B16%5D%5B17%5D} The classic Miller–Urey experiment and similar research demonstrated that most amino acids, the basic chemical constituents of the proteins used in all living organisms, can be synthesized from inorganic compounds under conditions intended to replicate those of the early Earth. Various external sources of energy that may have triggered these reactions have been proposed, including lightning and radiation. Other approaches ("metabolism-first" hypotheses) focus on understanding how catalysis in chemical systems on the early Earth might have provided the precursor molecules necessary for self-replication.^%5B18%5D Complex organic molecules have been found in the Solar System and in interstellar space, and these molecules may have provided starting material for the development of life on Earth.^{%5B19%5D%5B20%5D%5B21%5D%5B22%5D}

 

 

https://en.wikipedia.org/wiki/Iron–sulfur_world_hypothesis

 

The fundamental idea of abiogenesis, according to the iron–sulfur world hypothesis can be simplified in the following brief characterization: Pressurize and heat a water flow with dissolved volcanic gases (e.g. carbon monoxide, ammonia and hydrogen sulfide) to 100 °C. Pass the flow over catalytic transition metal solids (e.g. iron sulfide and nickel sulfide). Wait and locate the formation of catalytic metallo-peptides

 

 

 

 

[frankglennjacobs@gmail.com]

Are DNA and RNA similar?

 

Could RNA be a precursor to DNA?

 

Do we know how RNA originated?

 

Are there life forms today based on RNA instead of DNA?

 

(And you are right that I have an agenda: I want to be hailed by all the scientific world as the bumbling idiot who stumbled onto this.)

[pzkpfw]

Are DNA and RNA similar?

 

Could RNA be a precursor to DNA?

 

Do we know how RNA originated?

 

Are there life forms today based on RNA instead of DNA?

 

(And you are right that I have an agenda: I want to be hailed by all the scientific world as the bumbling idiot who stumbled onto this.)

Please see: https://en.wikipedia.org/wiki/RNA_world

[Moontanman]

Are DNA and RNA similar?

 

Could RNA be a precursor to DNA?

 

Do we know how RNA originated?

 

Are there life forms today based on RNA instead of DNA?

 

(And you are right that I have an agenda: I want to be hailed by all the scientific world as the bumbling idiot who stumbled onto this.)

 

 

Sooo... you didn't visit any of the links I provided?

[frankglennjacobs@gmail.com]

I went to Wiki RNA World and read as much as I could stand.

 

I am like the cowboy in the western movie who looked at the cards he was dwelt, declared, "I'm all in!" and quit for that hand.

 

That is WAY over my head. I had better go back to trying to invent a better can-opener.

Edited May 9, 2017 by frankglennjacobs@gmail.com