Origin of life insight: peptides can form without amino acids

peptide
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Peptides, one of the fundamental building blocks of life, can be formed from the primitive precursors of amino acids under conditions similar to those expected on the primordial Earth, finds a new UCL study.

The findings, published in Nature, could be a missing piece of the puzzle of how life first formed.

"Peptides, which are chains of amino acids, are an absolutely essential element of all life on Earth. They form the fabric of proteins, which serve as catalysts for biological processes, but they themselves require enzymes to control their formation from amino acids," explained the study's lead author, Dr. Matthew Powner (UCL Chemistry).

"So we've had a classic chicken-and-egg problem—how were the first enzymes made?"

He and his team have demonstrated that the precursors to amino acids, called aminonitriles, can be easily and selectively turned into peptides in water, taking advantage of their own built-in reactivity with the help of other molecules that were present in primordial environments.

"Many researchers have sought to understand how peptides first formed to help life develop, but almost all of the research has focused on amino acids, so the reactivity of their precursors was overlooked," said Dr. Powner.

The precursors, aminonitriles, require , typically strongly acidic or alkaline, to form amino acids. And then amino acids must be recharged with energy to make peptides. The researchers found a way to bypass both of these steps, making peptides directly from energy-rich aminonitriles.

They found that aminonitriles have the innate reactivity to achieve peptide bond formation in water with greater ease than amino acids. The team identified a sequence of simple reactions, combining hydrogen sulfide with aminonitriles and another chemical substrate ferricyanide, to yield peptides.

"Controlled synthesis, in response to environmental or internal stimuli, is an essential element of metabolic regulation, so we think that peptide synthesis could have been part of a natural cycle that took place in the very early evolution of life," said Pierre Canavelli, the first author of the study who completed it while at UCL.

The molecules that served as substrates to help the formation of the amide bonds in the experiments are outgassed during volcanism and are all likely to have been present on the early Earth.

"This is the first time that peptides have been convincingly shown to form without using in water, using relatively gentle conditions likely to be available on the primitive Earth," said co-author Dr. Saidul Islam (UCL Chemistry).

The findings may also be useful to the field of synthetic chemistry, as amide bond formation is essential for many commercially important synthetic materials, bioactive compounds and pharmaceuticals. The method used in this study is chemically unconventional but follows a pathway to ligate (join together) peptides that mimics , unlike peptide-building pathways more commonly used in chemistry laboratories that run in the opposite direction and require expensive and wasteful reagents.

The research team is furthering their studies by searching for other pathways to peptides using aminonitriles, and investigating the functional properties of the that their experiments have produced, to better understand how they could have helped kick start 4 billion years ago.


Explore further

Artificial peptide bond formation provides clues to creation of life on Earth

More information: Peptide ligation by chemoselective aminonitrile coupling in water, Nature (2019). DOI: 10.1038/s41586-019-1371-4 , https://nature.com/articles/s41586-019-1371-4
Journal information: Nature

Citation: Origin of life insight: peptides can form without amino acids (2019, July 10) retrieved 14 October 2019 from https://phys.org/news/2019-07-life-insight-peptides-amino-acids.html
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Jul 10, 2019
Whatever chemicals were involved in the initial process of creating Life, the fact still remains that the process of creating that Life was primarily initiated by an outside motivator, and that motivator was the Creator God. Peptide, amino acids, and whichever other chemicals were also involved in the creating of the first single-celled animals, those chemicals had already been available in the seawaters of Earth for at least a billion years or more. The motion of seawater would have given every opportunity for those chemicals to gather together to make a life form after all those billions of years. But nothing could be created until the Creator God decided that it was time to bring Life to this planet Earth, and then let that Life evolve itself into various and different species with various appearances, requirements, adaptabilities, and growth possibilities.
First, it was the animals and plants on the land and in the seas. Then later, humans were created by the Creator God.

Jul 10, 2019
...the fact still remains that the process of creating that Life was primarily initiated by an outside motivator, and that motivator was the Creator God.


This is a science site. Please demonstrate that "fact."

Jul 11, 2019
This is nice work. The problem of how to create a steady supply of amino-acids, ribose, and phosphates in the same primitive abiological environment is a major hurdle to understanding abiogenesis. So this result is a big deal.

The question remains however: is it thermodynamically feasible? (i.e. would it happen spontaneously in the kinds of environments that may have existed).

Jul 11, 2019
"Peptide, amino acids, and whichever other chemicals were also involved in the creating of the first single-celled animals, those chemicals had already been available in the seawaters of Earth for at least a billion years or more. The motion of seawater would have given every opportunity for those chemicals to gather together to make a life form after all those billions of years."

You reveal the breadth of your ignorance and the depth of your arrogance in these few sentences. The first living organisms were not "single-celled animals", which did not evolve until life had already existed for a couple of billion years; there are possible chemical traces of life in the oldest sedimentary rocks known; and the "motion of seawater" is not proposed as capable of producing life from precursor chemicals by any serious researcher. Why not try actually learning something about the areas which your tedious pontifications cover?

Jul 12, 2019
My "tedious pontifications" are based on the fact that chemicals in seawater were the progenitors of that which was brought together by an Intelligence whose goal was to create such Life.
Then generational Life arose from the simplest single-celled organisms in seawater. The chemicals in seawater, by themselves, were not 'programmed' or had a 'plan' to effect the cellular design and its constituents to gain a 'quickening', which is the signal that Life had any sort of viability. It takes far more than a smattering of some chemicals to congeal into a cellular design, and then gain an ability for locomotion and momentum.
Your atheism obviates the need for a Spiritual source to quicken Matter. But Matter itself is a dead thing. For if Matter was not a dead thing or substance, it would mean that you could live forever, barring any disease or accidental death.
Electrons, protons, atoms, molecules do not possess an ability to quicken Matter and give it Life.

Jul 12, 2019
All Life forms of Earth are cellular of many types of cells. All are cells, and it is those cells in the living that are actively doing as their ancestors did billions of Earth years ago. It is called "biogenesis" and it is ongoing as long as living cells are viable to carry on their work to preserve Life. Cells also want to preserve their OWN life. When the cells die and are no longer viable, their supply of DNA are intact, depending on the length of time those cells and its DNA have remained viable.
Life forms such as yourself, are a walking bag of cells. And your ancestral cells had their beginning in the seawater of Earth.
Incidentally, scientists are STILL trying to create life through abiogenesis. They always fail miserably and always will. They too do not recognise the existence of the original Creator.

Jul 12, 2019
Abiogenesis is a false and pretentious allusion to the formation of Life without that Life having had a progenitor/ancestor to pass down its inherited qualities such as DNA to its offspring/descendant.
Scientists who believe that they can produce Life through Abiogenesis by the use of chemistry without the Spiritual Force, are doomed to failure always. Each time that scientists have claimed success, it has turned out that they involved and utilised a cell or DNA/RNA, etc. of something that was previously living. But they claimed that they had created life, when ir reality they had done it out of something that had previously been a part of a living creature. That is FAKE SCIENCE.

Jul 12, 2019
...the fact still remains that the process of creating that Life was primarily initiated by an outside motivator, and that motivator was the Creator God.


This is a science site. Please demonstrate that "fact."
says observicist

Consider it done.

Jul 12, 2019
Are Pristine Protons and Pristine Electrons Alive

- Abiogenesis -
Or the origin of life
The natural process
By which life has arisen from non-living matter
Such as simple organic compounds

- Organic compounds -
In chemistry
An organic compound are any chemical compound
That contains carbon
Due to carbon's ability to catenate
Form chains with other carbon atoms
Millions of organic compounds are known
Known as organic chemistry

- Biogenesis -
Biogenesis is the production of living organisms
Or organelles
Conceptually
Biogenesis is attributed to Louis Pasteur
Encompasses the belief
Complex living things
Come only from other living things
By means of reproduction
That is, life does not spontaneously arise from non-living material

Foreth if life is bereft a soul
meaneths we are alive
We are the sum of our parts
A soul is the collective sum of our parts
Foreth thiseth meaneths
Pristine Protons and Pristine Electrons are Alive

SEU, for to be alive is to have a soul

Jul 12, 2019
These Protons Neutrons Electrons are Alive

For into this infinite vacuous vacuum
there appeared a pristine proton
then in this vacuum there appeared a pristine electron
where this lonely proton spied a scrumptious electron in the vacuum
where in this Gretna green of infinity
these proton and scrumptious electron eloped
for in to this infinite darkness these newlywed couple honey mooned together
where they spied a neutron
for then their family was complete
for from this trio
pristine protons
pristine electrons
pristine neutrons
were born into this infinite vacuum
for this circle of pristine LIFE
were BORN
into this infinite vacuum
foreth SEU
this Proton Neutron Electron are ALIVE

Foreth SEU if you truly BELIEVE
for this belief
is assigned that all powerful creative force
that force that giveth life
to these humble protons neutrons electrons

SEU, for if you're FAITH is UNWAVERING and STRONG
These Protons Neutrons Electrons are Alive

Jul 12, 2019
SEU, for if you're FAITH is UNWAVERING and STRONG

Foreth, SEU
being sent
as a disciple
the chosen one
for down on this earthly creation
for
made of this same earthly creation
are made these human souls
as human souls are alive
SEU, for to be alive is to have a soul
for
SEU
to be left at the mercy of this human desire
your Belief has become Weak
your Soul has been led Astray
the Devil in your heart has led you Astray
for every atomic particle in your human body
created by that all-powerful force
this earthly existence has made you doubt your FAITH
foreth, SEU
your earthly soul needs quiet contemplation
in your monastic life
for in this earthly living soul
your soul SEU
Needs Quite Reflection
for your Eternal Soul is at Stake
for your Bridge awaits this quiet reflection
this quiet contemplation
as you have been led a stray
Foreth SEU you have Committed a Mortal Sin

Every One Of These Creatures of Creation are Alive

Jul 12, 2019
Jebus made everything!!!111!!oneonetyeleven!!!

https://i.redd.it/hojas99fzkn11.jpg

Jul 12, 2019
...the fact still remains that the process of creating that Life was primarily initiated by an outside motivator, and that motivator was the Creator God.


This is a science site. Please demonstrate that "fact."
says observicist

Consider it done.


So you talk of GOD, but looking at your history here, you can't give a flying.... pigny about the earth's climate that GOD created.... Very twisted indeed..

Jul 13, 2019
The Earth is constructed of Matter/Energy as is everything else. It is all recyclable, just as every cell of your body. Those cells and the cells of every living creature and plant had its beginning in the quantum universe wherein the progenitors that are the protons, electrons, neutrons, quarks, etc. build up to the atomic level, and from there up to molecules, and from there to living cells. Molecules in and of themselves are not alive. It is only when they attain the qualities of a cell that they come alive. It is the cell that passes on its qualities to its daughter cells, and from there those qualities are distributed exponentially to future generations, following the Fibonacci Method/Numbers. It has always been that way since the first living cell was created in the waters of Earth.
You are free to disbelieve that the first cell was created, but then you are negating not just the Creator, but also Nature. Nature also depends on ancestors.

Jul 13, 2019
First there was the Great Flood that wiped out most life from the face of the Earth. But some escaped that Flood.
Now look around you, at what is going on in the world. Look at all the evil that is heppening. There is some good, but very soon all the good in the world will be supplanted by the evil, and it is that evil that will thrive and become stronger, so that the Earth will once again have to be cleansed of all that Lucifer/Satan is encouraging amongst humans.
Perhaps you don't recognise that the evil things are aiming to take over most, if not all, of humanity. As the years pass, you will notice that things are not right with humanity, and that something is very wrong. The news will get far worse, and yet, what is bad will be called good.
You may live to see it yet.
And by the way, when something is "created", the act of creating IS Science. Science involves a method and a plan or program, as does creation. It can also be experimental.

Jul 14, 2019
The fact that all is recyclable does not validate the fact that you don't Care about the climate which affects EVERYONE on Earth.

IF You believe in GOD, GOD tells you to respect, care for, and help people. Yet you preach of not giving a flying F about the well being of Earth.

And doing everything you possibly can imagine to disprove Science. I believe in GOD, but the difference is that I believe in SCIENCE too, just as much ! ! Because THATS the only tool we were given to study the Universe in our physical existence. And it works ! !

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