Molecular basis of Arginine and Lysine DNA sequence-dependent thermo-stability modulation

TitleMolecular basis of Arginine and Lysine DNA sequence-dependent thermo-stability modulation
Publication TypeJournal Article
Year of Publication2022
AuthorsMartin, Benjamin, Dans Pablo D., Wieczór Milosz, Villegas Núria, Brun-Heath Isabelle, Battistini Federica, Terrazas Montserrat, and Orozco Modesto
JournalPLoS computational biology
Paginatione1009749 - e1009749
Date Published01/2022
ISBN Number1553-73581553-734X
Keywords*Amino Acids, Basic/analysis/chemistry, *Base Sequence, *DNA/analysis/chemistry, Aminobutyrates/chemistry, Base Composition, Molecular Dynamics Simulation, Origin of Life, Thermodynamics

We have used a variety of theoretical and experimental techniques to study the role of four basic amino acids-Arginine, Lysine, Ornithine and L-2,4-Diaminobutyric acid-on the structure, flexibility and sequence-dependent stability of DNA. We found that the presence of organic ions stabilizes the duplexes and significantly reduces the difference in stability between AT- and GC-rich duplexes with respect to the control conditions. This suggests that these amino acids, ingredients of the primordial soup during abiogenesis, could have helped to equalize the stability of AT- and GC-rich DNA oligomers, facilitating a general non-catalysed self-replication of DNA. Experiments and simulations demonstrate that organic ions have an effect that goes beyond the general electrostatic screening, involving specific interactions along the grooves of the double helix. We conclude that organic ions, largely ignored in the DNA world, should be reconsidered as crucial structural elements far from mimics of small inorganic cations.

Short TitlePLoS Comput Biol