An L-DNA G-quadruplex: application for peroxidase DNAzyme

Area of Science:

• Biochemistry
• Molecular Biology
• Synthetic Biology

Background:

• Natural DNA (D-DNA) is composed of right-handed structures.
• Left-handed DNA (L-DNA) is the enantiomeric mirror image of D-DNA.
• G-quadruplexes are four-stranded nucleic acid structures formed by guanine-rich sequences.

Purpose of the Study:

• To investigate the formation and properties of L-DNA intramolecular G-quadruplexes.
• To explore the potential of L-DNA G-quadruplexes as DNAzymes with catalytic activity.
• To assess the applicability of L-DNAzyme in nuclease-containing biological environments.

Main Methods:

• Synthesis of a left-handed G-rich DNA sequence.
• Structural analysis of the L-DNA G-quadruplex formation.
• Assay of the peroxidase-like catalytic activity of the L-DNAzyme using ABTS.
• Visual observation of color change indicating catalytic activity.

Main Results:

• A left-handed G-rich DNA sequence successfully formed an intramolecular L-DNA G-quadruplex.
• The L-DNA G-quadruplex demonstrated significant peroxidase catalytic efficiency, functioning as a DNAzyme.
• The catalytic activity resulted in a visually observable color change of the ABTS substrate.

Conclusions:

• L-DNA can form functional G-quadruplex structures.
• L-DNA G-quadruplexes can act as peroxidase DNAzymes with observable catalytic activity.
• This L-DNAzyme offers a novel concept for applications in biological systems, particularly those with nuclease activity.