Synthetic genetics is an area of synthetic biology that aims to extend the properties of heredity and evolution to artificial genetic polymers, commonly known as xeno‐nucleic acids or XNAs. In addition to establishing polymerases that are able to convert genetic information back and forth between DNA and XNA, efforts are underway to construct XNAs with expanded chemical functionality. α‐L‐Threose nucleic acid (TNA), a type of XNA that is recalcitrant to nuclease digestion and amenable to Darwinian evolution, provides a model system for developing XNAs with functional groups that are not present in natural DNA and RNA. Here, we describe the synthesis and polymerase activity of a cytidine TNA triphosphate analog (6‐phenyl‐pyrrolocytosine, tCpTP) that maintains Watson‐Crick base pairing with guanine. Polymerase‐mediated primer extension assays show that tCpTP is an efficient substrate for Kod‐RI, a DNA‐dependent TNA polymerase developed to explore the functional properties of TNA by
Functional nucleic acids lose activity when their sequence is prepared in the backbone architecture of a different genetic polymer. The only known exception to this rule is a subset of aptamers whose binding mechanism involves G-quadruplex formation. We refer to such examples as transliteration—a synthetic biology concept describing cases in which the phenotype of a nucleic acid molecule is retained when the genotype is written in a different genetic language. Here, we extend the concept of transliteration to include nucleic acid enzymes (XNAzymes) that mediate site-specific cleavage of an RNA substrate. We show that an in vitro selected 2′-fluoroarabino nucleic acid (FANA) enzyme retains catalytic activity when its sequence is prepared as α-l-threofuranosyl nucleic acid (TNA), and vice versa, a TNA enzyme that remains functional when its sequence is prepared as FANA. Structure probing with DMS supports the hypothesis that FANA and TNA enzymes having the same primary sequence can adopt similarly folded tertiary structures. These findings provide new insight into the sequence-structure-function paradigm governing biopolymer folding.
more » « less- NSF-PAR ID:
- 10305480
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Nucleic Acids Research
- Volume:
- 49
- Issue:
- 20
- ISSN:
- 0305-1048
- Page Range / eLocation ID:
- p. 11438-11446
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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