HACHIMOJI DNA & RNA CODING | NASA
SINGULARITYHUB | BIOTECHNOLOGY | 02.24.2019
SCIENTISTS JUST ADDED 4 NEW LETTERS TO THE GENETIC CODE
A 4-letter alphabet might seem limited , but it is all nature needed to write the instructions for all life on the planet . News that researchers have added 4 letters to the genetic alphabet opens the door to new possibilities in synthetic biology , data storage , and even the search for life beyond the planet .
The genetic code at the heart of all living things is elegantly simple . Each half of the famous double helix structure is built from 4 small molecules called bases : adenine , thymine , cytosine and guanine ( ATCG ) . The order of appearance determines what the DNA codes for , just like series of zeros and ones at the hearts of computers do .
Now scientists at the Foundation for Applied Molecular Evolution in Florida have successfully added 4 new bases to create what is called Hachimoji DNA ( 8 letter DNA in Japanese ) , doubling the potential information density of genetic code .
SCIENCE | VOL 363 | ISSUE 6429 | PDF | 02.22.2019
HACHIMOJI DNA & RNA : A GENETIC SYSTEM WITH 8 BUILDING BLOCKS | SHUICHI HOSHIKA ETAL
EXPANDING THE GENETIC CODE | DNA & RNA are naturally composed of 4 nucleotide bases that form hydrogen bonds in order to pair . Hoshika etal added an additional 4 synthetic nucleotides to produce an 8 letter genetic code and generate so called Hachimoji DNA . Coupled with an engineered T7 RNA polymerase , this expanded DNA alphabet could be transcribed into RNA .
Thus , new forms of DNA that add information density to genetic biopolymers can be generated that may be useful for future synthetic biological applications .
ABSTRACT | Reported are DNA and RNA like systems built from 8 nucleotide letters ( hence the name Hachimoji ) that form 4 orthogonal pairs . These synthetic systems meet the structural requirements needed to support Darwinian evolution , including a polyelectrolyte backbone , predictable thermodynamic stability , and stereoregular building blocks that fit a Schrodinger aperiodic crystal .
Measured thermodynamic parameters predict the stability of Hachimoji duplexes , allowing Hachimoji DNA to increase the information density of natural terran DNA . 3 crystal structures show that the synthetic building blocks do not perturb the aperiodic crystal seen in the DNA double helix . Hachimoji DNA was then transcribed to give Hachimoji RNA in the form of a functioning fluorescent Hachimoji aptamer .
These results expand the scope of molecular structures that might support life , including life throughout the Cosmos .
NATURE | NEWS | 02.21.2019
4 NEW DNA LETTERS DOUBLE LIFE ALPHABET
Synthetic DNA seems to behave like the natural variety , suggesting that chemicals beyond nature's 4 familiar bases could support life on Earth .
The DNA of life on Earth naturally stores its information in just 4 key chemicals — guanine , cytosine , adenine and thymine , commonly referred to as G , C , A and T , respectively .
Now scientists have doubled this number of life's building blocks , creating for the first time a synthetic , 8 letter genetic language that seems to store and transcribe information just like natural DNA .
WIRED | SCIENCE | 02.21.2019
DOUBLING DNA BUILDING BLOCKS COULD LEAD TO NEW LIFE FORMS
If all of biology could be boiled down to a simple equation , it would be that DNA makes RNA , which makes proteins , which are what make every living thing one can see , smell , touch , and taste ( and a lot of things one cannot ) . This central dogma of biology , built on strings of Cs , Gs , As , and Ts , has prevailed since Francis Crick , James Watson , and Rosalind Franklin discovered DNAs double helix . Now thats changing as scientists expand the code of life beyond the 4 letters provided by nature .
Researchers have just unveiled the latest feat in artificial DNA engineering : an 8 letter synthetic system called Hachimoji DNA . From the Japanese hachi for 8 and moji for letter , the system is made up of 4 natural nucleotides and 4 synthetic ones that all fit seamlessly into DNAs helical structure , maintaining its natural shape . Moreover , sequences spelled with these new letters pair predictably , and can evolve just like natural DNA .
SOURCE | SATYAVEDISM.ORG