The entire biological life on planet Earth is based on four nucleic (nitrogenous) bases of DNA: A, T, C and G (adenine, cytosine, thymine and guanine). But what happens if a person manages to create new artificial nucleic bases and sew them into the DNA of the body? Researchers from the Research Institute Scripps managed to crank just such a trick. The scientists created two completely new nucleic bases and created the first semisynthetic bacterium on the basis of this “unnatural” DNA.
For several years, researchers from Scripps have been working to create a stable living organism with artificial DNA base pairs. The artificial nitrogen bases created by them were given uncomplicated names “X” and “Y”, so artificial DNA can now include six building elements: A, T, C, G, X and Y. Scientists have integrated new elements into the DNA of E. coli bacteria (Escherichia coli), thereby creating for the first time a strain of semisynthetic organisms. In the course of the experiments, the researchers came to the conclusion that the semisynthetic bacteria stabilized by them are not only able to grow and divide, but also transmit the synthetic nucleobases “X” and “Y” to new generations in a completely natural way.
The next stage of the research was to get the bacteria to generate completely new molecules using the nucleic bases they had found. All organisms produce proteins from amino acid strands, using the basic four letters of the “alphabet of DNA.” The life that we know is based on 20 standard amino acids. But adding only two new letters to the “alphabet”, the scientists obtained an organism capable of generating up to 152 entirely new amino acids. All this means only one thing: semisynthetic bacteria are able to create new molecules that could hypothetically become the basis for, for example, new drugs and so on.
To illustrate this feature of semisynthetic organisms visually, scientists forced bacteria to produce a special fluorescent protein that glows in the dark (you can see it in the photo a little higher). This protein was the first artificial molecule ever created by a semisynthetic organism. It is very difficult to assess the potential of this scientific breakthrough. For today, scientists are still experimenting with changing the expression of existing genes with the help of special mechanisms of gene editing . Now, researchers will be able to get their hands on a much more impressive mechanism for creating completely new forms of life and new molecules. The results of the study you can read in the journalNature.