Mirror image enzyme constructs longest ever mirror DNA strand

Researchers have synthesised a mirror image enzyme that allowed them to constructing the longest ever strand of mirror DNA. The team also demonstrated how this L-DNA could be used as a robust biorthogonal information repository. Louis Pasteur first proposed the idea of a mirror image version of biological systems more than 160 years ago, following the discovery of molecular chirality. All natural DNA contains the D form of the chiral sugar deoxyribose, but it may be possible for a mirror system to be built using L-deoxyribose instead. The mirror image DNA polymerase (right) can assemble mirror image DNA strands In the time since Pasteur’s proposal, however, no full mirror image systems have been discovered in nature or synthesised within a lab. Researchers have previously synthesised small L-oligonucleotides and D-proteins, but synthesising longer molecules has not been possible without the use of chirally inverted enzymes. Such size restrictions have limited the complexity of the systems researchers were able to produce . Now, a team of researchers in China has chemically synthesised the mirror image of a 775 amino acid Pyrococcus furiosus DNA polymerase – an enzyme that duplicates DNA strands, assembling the new ones nucleoside triphosphates building blocks. The particular enzyme was chosen because it is thermostable and makes few mistakes while copying DNA, properties that have made it one of the most widely used enzymes for the copying DNA sample via the polymerase chain reaction. Using their synthesised enzyme, the team was then able to assemble a mirror image DNA sequence containing 1500 base pairs , far longer than any previously achieved. Since L-DNA is more robust than its natural counterpart, it could act as a long-term information repository. When the team stored L- and D-DNA barcode sequences in water from a local pond, the natural D-DNA could only be amplified and read out for one day. In contrast, the L-DNA barcode could be amplified and sequenced one year later. To reflect mirror image biology’s origins, the team encoded a paragraph by Louis Pasteur discussing the concept in one of their L-DNA strands.ReferencesC Fan, Q Deng and T F Zhu,Nat. Biotechnol., 2021, DOI: 10.1038/s41587-021-00969-6 Related articlesOpinionWhy is life chiral?2018-03-19T16:00:00ZThe mystery of handedness could soon be unravelledResearchMeteorite compounds hint at origins of life’s asymmetry2016-06-01T00:00:00ZExcess of right handed sugar derivatives found on meteorites suggests homochirality may have come from spaceFeatureThe origin of homochirality2015-10-26T00:00:00ZWhy do so many biological molecules exist in just one chirality – and how did it emerge? Rachel Brazil reflects on life’s strange asymmetry More NewsResearchGiant crystal lattice is mesoporous but not a MOF2021-08-05T13:14:00ZNon-covalent network has the largest unit cell among non-MOFsBusinessFire in Russian chemical plant kills one, injures six2021-08-05T12:04:00ZGovernment to investigate a fatal fire at military production facility in southern RussiaResearchThere was more than simple oxygen depletion to ancient mass extinction event2021-08-05T08:30:00ZThallium isotopes reveal that rapid swings in ocean oxygenation preceded the events that wiped out 90% of species 250 million years ago SubscribeAdvertiseTopicsIssuesContributors Our mission News and events Campaigns Awards and funding Global challenges Support our work © Royal Society of Chemistry Registered charity number: 207890 Site powered by Webvision Cloud