Research creates DNA-like molecule to aid search for alien life

February 21, 2019 by Dwayne Brown / Elizabeth Landau, NASA
This illustration shows the structure of a new synthetic DNA molecule, dubbed hachimoji DNA, which uses the four informational ingredients of regular DNA (green, red, blue, yellow) in addition to four new ones (cyan, pink, purple, orange). Credit: Indiana University School of Medicine

In a research breakthrough funded by NASA, scientists have synthesized a molecular system that, like DNA, can store and transmit information. This unprecedented feat suggests there could be an alternative to DNA-based life, as we know it on Earth – a genetic system for life that may be possible on other worlds.

This new molecular system, which is not a new life form, suggests scientists looking for life beyond Earth may need to rethink what they are looking for. The research appears in Thursday's edition of Science Magazine.

DNA is a complex molecule that stores and transmits , is passed from parent to offspring in all living organisms on Earth, and its components include four key ingredients called nucleotides – all standard for life as we know it. But, what about life on other worlds?

"Life detection is an increasingly important goal of NASA's planetary science missions, and this new work will help us to develop effective instruments and experiments that will expand the scope of what we look for," said Lori Glaze, acting director of NASA's Planetary Science Division.

One way to imagine the kinds of foreign structures found on other worlds is to try to create something foreign on Earth. A team of researchers, led by Steven Benner at the Foundation for Applied Molecular Evolution in Alachua, Florida, successfully achieved the fabrication of a new informational molecular system that is like DNA, except in one key area: The new molecule has eight informational ingredients instead of four.

The synthetic DNA includes the four nucleotides present in Earth life – adenine, cytosine, guanine, and thymine – but also four others that mimic the structures of the informational ingredients in regular DNA. The result is a double-helix structure that can store and transfer information.

Crystyal structure of a hachimoji double helix built from four naturally-occurring bases, G (green), A (red), C (blue), T (yellow), and four synthetic bases, B (cyan), S (pink), P (purple), and Z (orange). Notable is the geometric regularity of the pairs, a requirement for evolution. Credit: Millie Georgiadis, Indiana University School of Medicine

Benner's team, which collaborated with laboratories at the University of Texas in Austin, Indiana University Medical School in Indianapolis, and DNA Software in Ann Arbor, Michigan, dubbed their creation "hachimoji" DNA (from the Japanese "hachi," meaning "eight," and "moji," meaning "letter"). Hachimoji DNA meets all the structural requirements that allow our DNA to store, transmit and evolve information in living systems.

"By carefully analyzing the roles of shape, size and structure in hachimoji DNA, this work expands our understanding of the types of molecules that might store information in extraterrestrial life on alien worlds," said Benner.

Scientists have much more to do on the question of what other genetic systems could serve as the foundation for life, and where such exotic organisms could be found. However, this study opens the door to further research on ways life could structure itself in environments that we consider inhospitable, but which might be teeming with forms of life we haven't yet imagined.

"Incorporating a broader understanding of what is possible in our instrument design and mission concepts will result in a more inclusive and, therefore, more effective search for life beyond Earth," said Mary Voytek, senior scientist for Astrobiology at NASA Headquarters.

One of NASA's goals is to search for life on other planets like Mars, where there was once flowing water and a thick atmosphere, or moons of the outer solar system like Europa and Enceladus, where vast water oceans churn under thick layers of ice. What if life on those worlds doesn't use our DNA? How could we recognize it? This new DNA may be the key to answering these questions and many more.

This work also interests those interested in information as part of life.

"The discovery that DNA with eight nucleotide letters is suitable for storing and transmitting information is a breakthrough in our knowledge of the range of possibilities necessary for ," said Andrew Serazin, president of Templeton World Charity Foundation in Nassau, The Bahamas, which also supported this work. "This makes a major contribution to the quest supported by Templeton World Charity Foundation to understand the fundamental role that information plays in both physics and biology."

Explore further: New NASA research consortium to tackle life's origins

More information: Hachimoji DNA and RNA: A genetic system with eight building blocks, Science  22 Feb 2019: Vol. 363, Issue 6429, pp. 884-887, DOI: 10.1126/science.aat0971 , http://science.sciencemag.org/content/363/6429/884

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Surveillance_Egg_Unit
1.7 / 5 (6) Feb 21, 2019
Other life forms are living on other worlds. They come in all sizes, shapes and sentience, and largely depend on the survivability of their home planet and the stability of the Star their planet orbits. Similar to the story of Homo Sapiens Sapiens on planet Earth.
Indeed, that is the Nature of Creation - to CREATE LIFE and then to allow it to flourish in whichever path it will follow - just as the life forms of Earth were created in the waters and then allowed to evolve and wend their way - to be fruitful and multiply. It is the same all over the Universe wherever there are planets that offer a home, and Stars that offer the means of continued life.
rrwillsj
3 / 5 (2) Feb 21, 2019
sillyegg, the LDS wants their storybook back. You weren't suppose to remove it from the reference stack at the library!

So, no alien life available to study? The scientists have to invent the BEM critter?

At least Dr. Frankenstein had corpses to harvest & look how well that worked out for him...

Panspermia cultistsclaim the Universe, or at least this region of the Milky Way, is infested with alien vermin. Sounds like a joke about the trumps.

That life started immediately after this galaxy began to form? Or at least after Pop I star systems formed?
Or when the first planets formed?
Or when all the local Pop I stars exploded five billion years ago? Propelling micro-life all across the galaxy?

Suddenly all the stars settled down with no more novas or supernovas to continue the process? Ever?

Which explains why only one single alien infected a sterile Earth? Which had no native pre-biochemistry ongoing?
That door was slammed shut for any competing alien?
plastikman
3.8 / 5 (6) Feb 22, 2019
The fundamental question is this. Can we digest an eight nucleotide beef-thing burger?
torbjorn_b_g_larsson
not rated yet Feb 22, 2019
Oy, superstition driven Templeton Foundation money and here outright lying comments - we observe _evolution_, nothing else .- despite showing robustness of evolution, and so fail of their magic - what an immoral lot they are. Stop the lies post haste.

But on the work, this does not change much, it is an extension of earlier work. Adding different sugars or bases for purposes of non-Tree Of Life applications has been done before: at least 6 new sugars in 2011 [ https://disq.us/u...=2285912]; natural sugars but 1 added base pair in 2014 [ https://disq.us/u...=2285912 ], 2 added base pairs in 2017 [ https://disq.us/u...=2285912 ].
torbjorn_b_g_larsson
not rated yet Feb 22, 2019
FWIW, the evolution of the nucleotide quaternary sequence underlying the later evolved triplet codon protein code has been suggested selected under four constraints to in the main balance RNA world enzymatic efficiency with replication accuracy [ https://disq.us/u...=2285912 it is handy and well referenced].

Same as the triplet code I would expect mostly quaternary codes on putative xeno-Trees Of Life but with possible chemical (i.e. used molecule) differences.
rrwillsj
1 / 5 (1) Feb 22, 2019
well, with trumpenella robbing the NASA & military space budgets to pay for the adorable uniforms (Design by Ivanka - Made in China) & shiny jackboots (gift from putin - made from the tanned hides of democratic socialists - wear these proudly! He does.).

For trumpsterfire's spanking-new Space Force Infantry & Camel Corps to parade in.
Before cheering throngs of hundreds,

Hey, it's a paying gig. Even getting paid by one of the trump crime family's bogus charities is better than no work at all for professional thespians.

America will sleep safe & secure from the insidious alien menace of imminent invasion by the evil Mars Supials!

What did you mean you weren't paid for attending a trumpeting rally? Are too stupid to get your stipend with everyone else?
Oh! Your boss ordered everyone to be there are not bother coming back to work.
Sorry I misunderstood.
So those weren't cheers but jeers for the Bogus POTUS?

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