Synthetic nucleotide bases change the way we see the building blocks of life

Most kids today have played with legos before. We build and destroy and rebuild with them. For a while, it’s interesting, we follow the manuals and the instructions, finish the intended project, and leave the lego structure alone, right? But what happens to that structure? It’s left sitting on a shelf, probably collecting dust (maybe the building gets put into a case if you’re a collector). Then, in a spurt of inspiration, we build something that was never instructed for in the manual! We take apart the original, study a bunch of different buildings, structures, and objects, and you make something entirely new!

What if I told you that the same thing was possible with genes and DNA.

Of course, biology and the basis of life are not the same as lego building blocks, but the idea is essentially the same. For a while, nature was utterly content with building life and DNA the original way. It used transcription and translation to create DNA, RNA, and proteins. Natural selection and mutations dictated the way organisms formed and if they survived. Then… humans came along, and we studied life, we picked apart how these essential molecules were affected by the general “nature of things,” and we decided to change them. Scientists took DNA and started to manipulate it to be what they wanted; they edited, cut, pasted, and turned DNA inside out. What was the next step? To change what DNA was made of, to change the nucleotide bases that were the fundamental building blocks of life! Scientists changed the legos!

So what is synthetic biology other than an extremely complex form of playing with legos?

Synthetic bio is the combination of biology and engineering; however, it is NOT genetic engineering. Instead of just cutting and pasting different nucleotide bases (or even whole portions of DNA) into the original sequence of nucleotide bases, synthetic biologists, actually make the DNA molecules, proteins, and RNA from scratch. Currently, synthetic biology focuses on the design and redesign of different biological components found on earth, and the fabrication of specific biological components that don’t already exist in the natural world. That means that not only can synthetic biologists create specific genomes that combine different genes in one cell, but they can also synthesize DNA and RNA such that these molecules work the same (and as well) as their natural counterparts. By using these synthetically made DNA molecules, scientists can put together whole genes and chromosomes that result in new phenotypes for specific organisms. In addition, they can redesign existing biological parts, make microbes produce enzymes that would enable them to then produce natural products (to use in industries), and design and construct entire genomes for simple bacteria.

Yet, the basis of life, the 4 original nucleotide bases were not changed. At least not until now!

Scientists have created 4 new nucleotide bases that can support life. Furthermore, with a 6 base pair DNA strand, scientists have created a living organism!

Think about that for a second. For centuries humans have understood that the fundamental building blocks of life were 4 nucleotide bases found in nature: A, T, C, and G. Now, scientists have created 4 completely new bases that can also support life! Additionally, they have made a 6 pair full strand of DNA code for a living being. This discovery means that those 4 original bases were not uniquely special, and there could potentially be living beings (on other planets) that have DNA that looks completely different from ours!

Regular DNA molecule

How did that happen?

To create these new base pairs, the researchers working on this 8 letter DNA code first had to synthesize hundreds if not more base possible base pairs and examine how well they paired up with their respective counterpart. To do even this, the scientists studied the original base pairs and tweaked different methyl groups that made up parts of the bases. In addition to just making these bases, there were some aspects of the base pairs that had to work absolutely right for them to be even considered as possible “life forming” molecules.

  • First: the base pairs had to bind selectively with their counterparts; they had to do so by hydrogen bonding.
  • Second: The base pairs COULD NOT inhibit, change, or disrupt the double-helical structure of DNA. Why? Because the whole reason DNA is so stable and works the way it does has a lot to do with the structure in which it is formed. → by testing the order and ways that the 4 new molecules paired, the scientists figured out that these new bases did not inhibit the structure of DNA
  • Third: This new DNA has to be able to synthesize proteins. Why? Yes, DNA makes up the genetic code of every living thing on this planet, but the whole reason it is so important is that it can be transcribed and translated in RNA and proteins that carry out functions within living things.

This new DNA, like regular, old fashioned DNA, can translate RNA strands and the transcribe amino acid chains to make proteins, which go on to code for characteristics.

Why does that matter?

Sure, the synthesis of a new building block of DNA is cool; they may even be classified as alien (although these bases cannot survive for long outside a lab), but that is not why they should be on our minds.

The synthesis of these new molecules could lead to totally new proteins, genes, and characteristics in living organisms.

Not only has this new DNA proved that A, T, C, and G are not unique, but it has the possibility to make completely new and never before seen products from organisms that have this DNA. This 8 letter DNA could store more genetic information than ever before, bind to targets better than ever, and create entirely new genes. This 8 letter DNA could be used to speed up chemical reactions or bind to liver cancer cells!

This new DNA would be able to synthesize new proteins, make new genes, and even give life to organisms we have never seen before. That takes genetic engineering one step further. By creating this new DNA, we have opened up the possibilities of any genotype (characteristic) a human can imagine; all that’s needed now is to figure out how to make them.

It works like this: because 4 new bases were created, the number of bases doubled, which also means that at the very least, storage space for genetic information has doubled as well. All the known characteristics even documented have been a result of the original 4 letter DNA; now, we can create new ones.

That changes everything! This new DNA brings in a couple of conclusions:

  • The four nucleotide bases that we know are not special. Life can be formed by bases that have different characteristics.
  • Humans have created new building blocks for life
  • these building blocks were made using synthetic biology practices and editing the original base pairs
  • This new DNA has more storage for genes and proteins. Therefore, entirely new genes could be made using the organisms that have this 8 letter DNA could exhibit characteristics only limited by the human mind.

Right now the synthetic bio community is at 4 base pairs (8 letters), but they are aiming for 10, or even 12 letters! That means more possibilities for life!

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A 16-year old synthetic bio researcher looking to intersect molecular bio technologies and neurology!