Can a denaturant stabilize DNA? Pyridine reverses DNA denaturation in acidic pH

The stability of DNA is highly dependent on the properties of the surrounding solvent, such as ionic strength, pH, and the presence of denaturants and osmolytes. Addition of pyridine is known to unfold DNA by replacing π-π stacking interactions between bases, stabilizing conformations in which the n...

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Detalles Bibliográficos
Autores: Portella, Guillem, Terrazas Martínez, Montserrat, Villegas, Núria, González, Carlos, Orozco López, Modesto
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2015
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/183793
Acceso en línea:https://hdl.handle.net/2445/183793
Access Level:acceso abierto
Palabra clave:ADN
Àcids nucleics
Dinàmica molecular
DNA
Nucleic acids
Molecular dynamics
Descripción
Sumario:The stability of DNA is highly dependent on the properties of the surrounding solvent, such as ionic strength, pH, and the presence of denaturants and osmolytes. Addition of pyridine is known to unfold DNA by replacing π-π stacking interactions between bases, stabilizing conformations in which the nucleotides are solvent exposed. We show here experimental and theoretical evidences that pyridine can change its role and in fact stabilize the DNA under acidic conditions. NMR spectroscopy and MD simulations demonstrate that the reversal in the denaturing role of pyridine is specific, and is related to its character as pseudo groove binder. The present study sheds light on the nature of DNA stability and on the relationship between DNA and solvent, with clear biotechnological implications.