AI Article Synopsis
- The study uses differential scanning calorimetry and UV thermal denaturation to analyze how the peptide antibiotic echinomycin interacts with DNA, providing a complete thermodynamic profile.
- The findings report a free energy change (DeltaG) of -7.6 kcal/mol, indicating the binding is favorable, with a positive enthalpy (DeltaH = +3.8 kcal/mol) and a significant positive entropy (DeltaS = +38.9 cal/mol·K) at 20°C.
- The results suggest that while the interaction is mainly driven by hydrophobic forces, direct molecular recognition, including hydrogen bonding and van der Waals interactions, also contributes significantly to the stability of the echinomycin-DNA complex.
Article Abstract
Differential scanning calorimetry and UV thermal denaturation have been used to determine a complete thermodynamic profile for the bis-intercalative interaction of the peptide antibiotic echinomycin with DNA. The new calorimetric data are consistent with all previously published binding data, and afford the most rigorous and direct determination of the binding enthalpy possible. For the association of echinomycin with DNA, we found DeltaG degrees = -7.6 kcal mol(-1), DeltaH = +3.8 kcal mol(-1) and DeltaS = +38.9 cal mol(-1) K(-1) at 20 degrees C. The binding reaction is clearly entropically driven, a hallmark of a process that is predominantly stabilized by hydrophobic interactions, though a deeper analysis of the free energy contributions suggests that direct molecular recognition between echinomycin and DNA, mediated by hydrogen bonding and van der Waals contacts, also plays an important role in stabilizing the complex.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC275468 | PMC |
| http://dx.doi.org/10.1093/nar/gkg826 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!