Distinctive Nucleic Acid Recognition by Lysine-Embedded Phenanthridine Peptides.

Area of Science:

• Chemical Biology
• Molecular Biology
• Spectroscopy

Background:

• Phenanthridine derivatives are explored for their nucleic acid binding properties.
• Understanding molecular interactions is key for developing diagnostic probes.

Purpose of the Study:

• Synthesize and characterize novel phenanthridine peptide derivatives.
• Investigate their potential as spectrophotometric probes for DNA and RNA.
• Evaluate the impact of structural modifications on binding affinity and selectivity.

Main Methods:

• Synthesis of phenanthridine peptide derivatives (compounds 19, 22, 23).
• Spectroscopic analysis (UV/Vis, circular dichroism).
• Mass spectrometry and computational modeling.
• Binding studies with various polynucleotides.

Main Results:

• Compounds 22 and 23, containing lysine, exhibited stronger DNA/RNA binding than compound 19.
• Compound 23 showed selective fluorimetric response and induced triplex formation with AT/ATT polynucleotides.
• A high binding constant (K = 2.5 × 10^7 M^-1) was achieved with AT and ATT polynucleotides.
• Selective recognition of ds-DNA, ds-RNA, and GC-rich DNA was observed via induced CD signals.

Conclusions:

• Lysine incorporation enhances binding affinity of phenanthridine derivatives to nucleic acids.
• Compound 23 serves as a selective probe for specific DNA/RNA sequences and structures.
• These derivatives hold promise for applications in molecular diagnostics and biophysical studies.