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Low-frequency vibrational modes in G-quadruplexes reveal the mechanical properties of nucleic acids.

ABSTRACT: Low-frequency vibrations play an essential role in biomolecular processes involving DNA such as gene expression, charge transfer, drug intercalation, and DNA-protein recognition. However, understanding the vibrational basis of these mechanisms relies on theoretical models due to the lack of experimental evidence. Here we present the low-frequency vibrational spectra of G-quadruplexes (structures formed by four strands of DNA) and B-DNA characterized using femtosecond optical Kerr-effect spectroscopy. Contrary to expectation, we found that G-quadruplexes show several strongly underdamped delocalized phonon-like modes that have the potential to contribute to the biology of the DNA at the atomic level. In addition, G-quadruplexes present modes at a higher frequency than B-DNA demonstrating that changes in the stiffness of the molecule alter its gigahertz to terahertz vibrational profile.

SUBMITTER: Gonzalez-Jimenez M

PROVIDER: S-EPMC8207511 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Low-frequency vibrational modes in G-quadruplexes reveal the mechanical properties of nucleic acids.

González-Jiménez Mario M Ramakrishnan Gopakumar G Tukachev Nikita V NV Senn Hans M HM Wynne Klaas K

Physical chemistry chemical physics : PCCP 20210604 23

Low-frequency vibrations play an essential role in biomolecular processes involving DNA such as gene expression, charge transfer, drug intercalation, and DNA-protein recognition. However, understanding the vibrational basis of these mechanisms relies on theoretical models due to the lack of experimental evidence. Here we present the low-frequency vibrational spectra of G-quadruplexes (structures formed by four strands of DNA) and B-DNA characterized using femtosecond optical Kerr-effect spectros ...[more]

PMID: 34095914

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