Comparison of the Thermodynamics and Base-Pair Dynamics of a Full LNA:DNA Duplex and of the Isosequential DNA:DNA Duplex

Bibliographic Details
Title: Comparison of the Thermodynamics and Base-Pair Dynamics of a Full LNA:DNA Duplex and of the Isosequential DNA:DNA Duplex
Authors: Bruylants, Gilles, Boccongelli, Marina, Snoussi, Karim, Bartik, Kristin
Source: Biochemistry, 48 (35
Publisher Information: American Chemical Society (ACS), 2009.
Publication Year: 2009
Subject Terms: 0301 basic medicine, 0303 health sciences, Molecular Structure, Circular Dichroism, Nucleic Acid Heteroduplexes, Oligonucleotides, Nucleic Acid Hybridization, Chemical, DNA, Sciences de l'ingénieur, Oligonucleotides -- chemistry, Nucleic Acid Heteroduplexes -- chemistry, 03 medical and health sciences, Models, Chemical, Models, Circular Dichroism -- methods, DNA -- chemistry, Chimie, Nucleic Acid Conformation, Thermodynamics, Thermodynamique chimique, Base Pairing
Description: Locked nucleic acids (LNA), conformationally restricted nucleotide analogues, are known to enhance pairing stability and selectivity toward complementary strands. With the aim to contribute to a better understanding of the origin of these effects, the structure, thermal stability, hybridization thermodynamics, and base-pair dynamics of a full-LNA:DNA heteroduplex and of its isosequential DNA:DNA homoduplex were monitored and compared. CD measurements highlight differences in the duplex structures: the homoduplex and heteroduplex present B-type and A-type helical conformations, respectively. The pairing of the hybrid duplex is characterized, at all temperatures monitored (between 15 and 37 degrees C), by a larger stability constant but a less favorable enthalpic term. A major contribution to this thermodynamic profile emanates from the presence of a hairpin structure in the LNA single strand which contributes favorably to the entropy of interaction but leads to an enthalpy penalty upon duplex formation. The base-pair opening dynamics of both systems was monitored by NMR spectroscopy via imino protons exchange measurements. The measurements highlight that hybrid G-C base-pairs present a longer base-pair lifetime and higher stability than natural G-C base-pairs, but that an LNA substitution in an A-T base-pair does not have a favorable effect on the stability. The thermodynamic and dynamic data confirm a more favorable stacking of the bases in the hybrid duplex. This study emphasizes the complementarities between dynamic and thermodynamical studies for the elucidation of the relevant factors in binding events.
Document Type: Article
File Description: 2 full-text file(s): application/pdf; application/pdf
Language: English
ISSN: 1520-4995
0006-2960
DOI: 10.1021/bi900615z
Access URL: https://pubmed.ncbi.nlm.nih.gov/19670874
https://pubmed.ncbi.nlm.nih.gov/19670874/
https://www.ncbi.nlm.nih.gov/pubmed/19670874
https://difusion.ulb.ac.be/vufind/Record/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/54636/Details
https://pubs.acs.org/doi/abs/10.1021/bi900615z
https://dial.uclouvain.be/pr/boreal/object/boreal:35339
https://pubs.acs.org/doi/10.1021/bi900615z
http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/54636
Accession Number: edsair.doi.dedup.....68f07b492f93b35d253fde4b8cf94797
Database: OpenAIRE
Description
ISSN:15204995
00062960
DOI:10.1021/bi900615z