Nature: "stable" semi synthetic organism creates "supernatural" protein

There are many kinds of life in nature, but there are only four kinds of bases in the DNA of all these life genetic materials, which are adenine (a), thymine (T), cytosine (c) and guanine (g), in which a and T, C and G are paired respectively Recently, Professor Floyd romesberg of the Scripps Research Institute published a semi synthetic organization that stores and retrieves artificial genetic information on nature, describing a semi synthetic organism that can store and retrieve non natural artificial genetic information Semi synthetic organisms (E.coli) produce green fluorescent protein (source: nature) by transforming the unnatural genetic code In 2014, Professor Floyd romesberg's team described a semi synthetic strain of E.coli In addition to four natural nucleotides, the strain also contains an extended genetic code, including two unnatural nucleotides X and y The bacteria can maintain and regenerate the modified genetic code, but it was not clear whether the unnatural nucleotide could be used to code proteins like normal DNA Now, romesberg and his colleagues have shown that the bacteria can transcribe and translate unnatural nucleotides (as efficient as natural nucleotides) to synthesize proteins containing unnatural amino acids, and the efficiency is not significantly different from that of natural proteins Professor Floyd romesberg (source: the San Diego Union) in Professor romesberg's own view, this result shows that in the field of synthetic biology, which focuses on instilling new characteristics into organisms, scientists can achieve their goals by re creating the most basic elements of life There is no other biological system that is more basic and close to the essence of life than the storage and extraction of genetic information What the research group has done is to design a new component that can run with the existing components and realize all the functions Professor George Church (source: Wyss Institute) Professor George church, a leading geneticist at Harvard Medical School, said that, including his team, there are multiple research teams around the world trying to study the repeated use of redundant codons to specify new amino acids Romesberg's team's research is unique: adding a new base pair to DNA will greatly increase the number of possible codons, theoretically giving cells the ability to use more than 100 extra amino acids According to Professor Peter Carr of Lincoln Laboratory at MIT, scientists are just beginning to understand rewriting life, but the research of romesberg group has told us that the known process of life germination may not be the only way, and may not be the best way It has long been a goal of synthetic biology to create organisms to produce unnatural modified proteins Scientists envisioned increasing genetic codes as early as the 1960s The first big success was achieved in 1989 by a team of geochemist Professor Steven Benner of the Federal Institute of technology in Zurich who proposed the "seeds of extraterrestrial life" For the first time, they successfully implanted the modified cytosine (c) and thymine (T) into DNA In response tests conducted in vitro, DNA chains with what Professor Benner called "interesting letters" successfully self copied and produced RNA and proteins According to Professor Benner, the romesberg team has taken another important step towards creating new life forms Romesberg's team used healthy cells synthesized with unnatural nucleotides In multiple experiments, the cells absorbed two unnatural amino acids, PRK and pazf, and the synthesized proteins gave off green fluorescence Both unnatural base pairs and unnatural amino acids are successfully absorbed by specific cells, and no organic compounds outside the laboratory can be synthesized In order to enable cells to make effective use of these new components, they developed a modified version of the new tRNA, which can effectively read the codon and synthesize the corresponding amino acids in the ribosome Synthorx (source: synthorx), a start-up of romesberg, these synthetic amino acids have not changed the shape and function of GFP But being able to store and read information in cells now means that this technology will have great potential in the future In the unpublished work, the romesberg team inserted unnatural bases into the key genes that can improve bacterial resistance to antibiotics, and bacteria with unnatural bases are more sensitive to penicillins Having more bases in an organism means adding extra letters to the letters of life, which allows biologists to expand the possibilities of synthesizing new proteins More bases also mean the possibility of free design and modification of molecules, and many thorny problems in medical chemistry will be solved To that end, romesberg has set up a start-up and raised $16 million One of the projects is to develop a new version of interleukin-2, which is an anti-cancer drug, but has great side effects New semi synthetic organisms may be able to weaken the side effects of drugs through component exchange at some critical moments Thesis link: https://