7-deaza-dG Promotes the Faithful Transcription of 4 Nucleotide TNA Polymers

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Description
DNA is a natural genetic polymer capable of storing and preserving genetic information in biological systems. Due to its natural information storage capacity, recent scientific progress demonstrates that DNA has the potential to exceed standard information storage technologies. However, DNA

DNA is a natural genetic polymer capable of storing and preserving genetic information in biological systems. Due to its natural information storage capacity, recent scientific progress demonstrates that DNA has the potential to exceed standard information storage technologies. However, DNA is limited in its information storage capacities due to its susceptibility to degradation in the presence of naturally occurring nucleases. Threose nucleic acid (TNA), an unnatural genetic polymer with a 3'->2'phosphodiester-linked threose sugar backbone, has promising potential to overcome this limitation. TNA is not a substrate for natural nucleases and thus shows a dramatic increase in stability compared to DNA. However, TNA transcription has a tendency to generate G:G mispairs and lead to a gradual loss of information within the template. It was hypothesized that the mutation occurs through a G:G Hoogsteen base pair that forms preferentially over the canonical G:C Watson-Crick base pair. Incorporation of 7-deaza-dG into a four letter template effectively eliminated G:G mispairings and improved the replication fidelity from 60% to 99.6% with only four errors in a thousand. These results have laid the groundwork for further research to increase the length of the TNA product synthesized and to test TNA's ability to store genetic information.
Date Created
2014-05
Agent

The Structural Diversity of Artificial Genetic Polymers

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Description

Synthetic genetics is a subdiscipline of synthetic biology that aims to develop artificial genetic polymers (also referred to as xeno-nucleic acids or XNAs) that can replicate in vitro and eventually in model cellular organisms. This field of science combines organic

Synthetic genetics is a subdiscipline of synthetic biology that aims to develop artificial genetic polymers (also referred to as xeno-nucleic acids or XNAs) that can replicate in vitro and eventually in model cellular organisms. This field of science combines organic chemistry with polymerase engineering to create alternative forms of DNA that can store genetic information and evolve in response to external stimuli. Practitioners of synthetic genetics postulate that XNA could be used to safeguard synthetic biology organisms by storing genetic information in orthogonal chromosomes. XNA polymers are also under active investigation as a source of nuclease resistant affinity reagents (aptamers) and catalysts (xenozymes) with practical applications in disease diagnosis and treatment. In this review, we provide a structural perspective on known antiparallel duplex structures in which at least one strand of the Watson–Crick duplex is composed entirely of XNA. Currently, only a handful of XNA structures have been archived in the Protein Data Bank as compared to the more than 100 000 structures that are now available. Given the growing interest in xenobiology projects, we chose to compare the structural features of XNA polymers and discuss their potential to access new regions of nucleic acid fold space.

Date Created
2015-12-15
Agent