Nucleotidyl transferase assisted DNA labeling with different click chemistries

Area of Science:

• Biochemistry
• Molecular Biology
• Organic Chemistry

Background:

• Oligonucleotide modification is crucial for various biotechnological applications.
• Efficient and versatile labeling strategies are needed for diverse DNA sources.

Purpose of the Study:

• To develop a simple, modular, and efficient strategy for 3'-terminal DNA labeling.
• To explore the utility of different click chemistry reactions for DNA modification.
• To investigate the impact of linker variants on labeling efficiency.

Main Methods:

• Incorporation of modified nucleotides at the 3'-terminus using terminal deoxynucleotidyl transferase.
• Conversion of incorporated nucleotides via four click chemistry reactions: copper-catalyzed azide-alkyne cycloaddition (CuAAC), strain-promoted azide-alkyne cycloaddition (SPAAC), Staudinger ligation, and Diels-Alder reaction.
• Introduction of internal modifications using ligation or primer extension prior to click reaction.
• Analysis of linker variant influence on azide reactivity in click reactions.

Main Results:

• Demonstrated a versatile strategy for 3'-terminal DNA labeling applicable to chemically synthesized, enzymatically synthesized, and naturally sourced DNA.
• Identified distinct substrate preferences among different click chemistry reactions, highlighting the importance of reaction choice for oligonucleotide labeling.
• Successfully extended a previously developed RNA labeling strategy to DNA using Staudinger ligation, a copper-free click chemistry method.

Conclusions:

• The presented strategy offers a robust and adaptable platform for 3'-terminal DNA labeling.
• Understanding substrate preferences of click chemistry is essential for optimizing biomolecule labeling.
• The findings facilitate the advancement of oligonucleotide modification techniques for research and diagnostics.