TY - JOUR

T1 - A Study of the DNA Structure in Films Using FTIR Spectroscopy

AU - Пастон, Софья Владимировна

AU - Поляничко, Александр Михайлович

AU - Шуленина, Ольга Владиславовна

AU - Осинникова, Дарья Николаевна

N1 - Publisher Copyright: © 2020, Pleiades Publishing, Inc.

PY - 2020/11

Y1 - 2020/11

N2 - The aqueous environment and ionic surroundings are the most important factors that determine the conformation of DNA and its functioning in the cell. The specificity of the interaction between DNA and cations is especially pronounced with a decrease in the activity of water. In this work, we use FTIR spectroscopy to study the B–A transition in high-molecular-weight DNA with a decrease in the humidity of the film with different contents of Na + ions. The IR spectrum of DNA is very sensitive to its secondary structure. As well, this makes it possible to evaluate the amount of DNA-bound water. Dehydration of the DNA film leads to changes in the IR absorption spectrum characteristic of the B–A transition. Using thermogravimetric analysis, we have shown that the degree of DNA hydration reaches the saturation level at a relative humidity of 60% and decreases slightly upon further drying. The amount of water that is strongly bound to DNA has been found to decrease with increasing Na + concentration. In this case, sodium ions destroy the hydration shell of DNA and can interact directly with phosphate groups.

AB - The aqueous environment and ionic surroundings are the most important factors that determine the conformation of DNA and its functioning in the cell. The specificity of the interaction between DNA and cations is especially pronounced with a decrease in the activity of water. In this work, we use FTIR spectroscopy to study the B–A transition in high-molecular-weight DNA with a decrease in the humidity of the film with different contents of Na + ions. The IR spectrum of DNA is very sensitive to its secondary structure. As well, this makes it possible to evaluate the amount of DNA-bound water. Dehydration of the DNA film leads to changes in the IR absorption spectrum characteristic of the B–A transition. Using thermogravimetric analysis, we have shown that the degree of DNA hydration reaches the saturation level at a relative humidity of 60% and decreases slightly upon further drying. The amount of water that is strongly bound to DNA has been found to decrease with increasing Na + concentration. In this case, sodium ions destroy the hydration shell of DNA and can interact directly with phosphate groups.

KW - B–A transition

KW - FTIR spectroscopy

KW - Keywords: DNA

KW - hydration

KW - secondary structure

KW - thermogravimetric analysis

UR - http://www.scopus.com/inward/record.url?scp=85102507461&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/11410fb0-5472-304d-ab4f-8b5a68ff18ce/

U2 - 10.1134/S0006350920060159

DO - 10.1134/S0006350920060159

M3 - Article

VL - 65

SP - 900

EP - 906

JO - Biophysics (Russian Federation)

JF - Biophysics (Russian Federation)

SN - 0006-3509

IS - 6

ER -