3 research outputs found
Expanding the Horizon of the Xeno Nucleic Acid Space: Threose Nucleic Acids with Increased Information Storage
Xeno nucleic acids
(XNAs) constitute a class of synthetic
nucleic
acid analogues characterized by distinct, non-natural modifications
within the tripartite structure of the nucleic acid polymers. While
most of the described XNAs contain a modification in only one structural
element of the nucleic acid scaffold, this work explores the XNA chemical
space to create more divergent variants with modifications in multiple
parts of the nucleosidic scaffold. Combining the enhanced nuclease
resistance of α-l-threofuranosyl nucleic acid (TNA)
and the almost natural-like replication efficiency and fidelity of
the unnatural hydrophobic base pair (UBP) TPT3:NaM, novel modified nucleoside triphosphates with a dual modification
pattern were synthesized. We investigated the enzymatic incorporation
of these nucleotide building blocks by XNA-compatible polymerases
and confirmed the successful enzymatic synthesis of TPT3-modified TNA, while the preparation of NaM-modified
TNA presented greater challenges. This study marks the first enzymatic
synthesis of TNA with an expanded genetic alphabet (exTNA), opening
promising opportunities in nucleic acid therapeutics, particularly
for the selection and evolution of nuclease-resistant, high-affinity
aptamers with increased chemical diversity
Strategies for Covalent Labeling of Long RNAs
The introduction of chemical modifications into long RNA molecules at specific positions for visualization, biophysical investigations, diagnostic and therapeutic applications still remains challenging. In this review, we present recent approaches for covalent internal labeling of long RNAs. Topics included are the assembly of large modified RNAs via enzymatic ligation of short synthetic oligonucleotides and synthetic biology approaches preparing site-specifically modified RNAs via in vitro transcription using an expanded genetic alphabet. Moreover, recent approaches to employ deoxyribozymes (DNAzymes) and ribozymes for RNA labeling and RNA methyltransferase based labeling strategies are presented. We discuss the potentials and limits of the individual methods, their applicability for RNAs with several hundred to thousands of nucleotides in length and indicate future directions in the field
Formylation of phenols using formamidine acetate
We report a new method to formylate phenol derivatives using formamidine acetate and acetic anhydride. This general-purpose transformation is a significant improvement over many other methods and does not require high temperatures or the addition of strong acid or base. Mono-, di-, and tri-formylated product can be obtained, depending on the substrate and conditions used