The Influence of Mn2+on DNA structure in the presence of Na+ions: A Raman spectroscopic study

The influence of Mn2+ions on the structure of natural calf thymus DNA was studied by Raman spectroscopy. Measurements were done at room temperature and pH 6.2±0.2, in the presence of the physiological concentration of 150 mM Na+ions, and in the presence of Mn2+concentrations that varied between 0 and 600 mM. No condensation of DNA was observed at any of the Mn2+concentrations. At 5 mM Mn2+and 150 mM Na+no significant influence of Mn2+ions on the DNA structure can be observed. Compared with our previous results obtained at 10 mM Na+ions, binding of Mn2+ions to charged phosphate groups and to DNA bases is inhibited in the presence of 150 mM Na+ions. DNA backbone conformational changes were not observed in the whole concentration range of Mn2+ions as judging from the Raman spectra. No evidence for DNA melting was identified. A high Mn2+affinity for binding to guanine N7 and possibly, in a much lesser extent, to adenine have been found.

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Mn2+–DNA interactions in aqueous systems: A Raman spectroscopic study

Spectroscopy An International Journal ◽

10.1155/2006/429147 ◽

2006 ◽

Vol 20 (1) ◽

pp. 29-35 ◽

Cited By ~ 17

Author(s):

Cristina M. Muntean ◽

Rolf Misselwitz ◽

Lubomir Dostál ◽

Heinz Welfle

Keyword(s):

Conformational Changes ◽

Room Temperature ◽

Critical Concentration ◽

Dna Denaturation ◽

Dna Interactions ◽

Raman Spectroscopic ◽

Calf Thymus ◽

Cacodylate Buffer ◽

Dna Backbone ◽

Phosphate Groups

Interaction of natural calf thymus DNA with Mn2+ions was studied by means of Raman spectroscopy. Spectra of DNA in 10 mM Na-cacodylate buffer, pH 6.2, 10 mM NaCl and in buffer containing Mn2+ions were measured at room temperature. Mn2+concentrations varied between 0 and 0.6 M. DNA backbone conformational changes and DNA denaturation were not observed in the concentration range 0 and 0.5 M, however, DNA condensation was observed at a critical concentration of 100 mM Mn2+that prevented the measurement of Raman spectra. Binding of Mn2+to the charged phosphate groups of DNA is indicated in the spectra. A high affinity of Mn2+for guanine N7 was obvious, and binding to adenine was barely suggested.

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Zn2+–DNA interactions in aqueous systems: A Raman spectroscopic study

Spectroscopy An International Journal ◽

10.1155/2009/317362 ◽

2009 ◽

Vol 23 (3-4) ◽

pp. 155-163 ◽

Cited By ~ 14

Author(s):

Cristina M. Muntean ◽

Konstantinos Nalpantidis ◽

Ingo Feldmann ◽

Volker Deckert

Keyword(s):

Room Temperature ◽

Helical Structure ◽

Intensity Change ◽

Dna Melting ◽

Dna Interactions ◽

Raman Spectroscopic ◽

Double Helical Structure ◽

Calf Thymus ◽

Concentration Changes ◽

Phosphate Groups

The influence of Zn2+ions on the structure of natural calf thymus DNA was studied by Raman spectroscopy. Measurements were done at room temperature and pH 6.2±0.1, in the presence of 10 mM Na+, and of Zn2+in a concentration range varying between 0 and 250 mM, respectively. No condensation of DNA was observed.As judging from the marker bands near 681 cm−1(dG), 729 cm−1(dA), 752 cm−1(dT), and 787 cm−1(dC, dT) altered nucleoside conformations in these residues are supposed to occur, in different intervals of Zn2+ions concentration. Changes in the conformational marker centered around 835 cm−1, upon Zn2+binding to DNA, were detected. Binding of zinc(II) ions to the charged phosphate groups of DNA, stabilizing the double helical structure, is indicated in the spectra. We have found that binding of metal ions at N3 of cytosine takes place at zinc(II) concentrations between 150–250 mM and interaction of Zn2+ions with adenine is observed in a concentration range from 10 to 250 mM. Binding of zinc(II) ions to N7 of guanine and, possibly, in a lesser extent to adenine was also observed as indicated by the Raman marker bands near 1490 and 1581 cm−1. There is no intensity change of the band at 1668 cm−1, suggesting no change in their base pairing and no change induced in the structure of water by Zn2+cations. No evidence for DNA melting was identified.

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A laser Raman spectroscopic study of the interaction of calf-thymus DNA with Cu(II) and Pb(II) ions: metal ion binding and DNA conformational changes

Nucleic Acids Research ◽

10.1093/nar/16.2.751 ◽

1988 ◽

Vol 16 (2) ◽

pp. 751-762 ◽

Cited By ~ 72

Author(s):

H.A. Tajmir-Riahi ◽

M. Langlais ◽

R. Savoie

Keyword(s):

Spectroscopic Study ◽

Conformational Changes ◽

Metal Ion ◽

Calf Thymus Dna ◽

Ion Binding ◽

Metal Ion Binding ◽

Raman Spectroscopic ◽

Laser Raman ◽

Raman Spectroscopic Study ◽

Calf Thymus

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Raman spectroscopic study of the effects of Ca2+, Mg2+, Zn2+, and Cd2+ ions on calf thymus DNA: Binding sites and conformational changes

Biopolymers ◽

10.1002/bip.360300709 ◽

1990 ◽

Vol 30 (7-8) ◽

pp. 743-752 ◽

Cited By ~ 93

Author(s):

Marc Langlais ◽

Heidar All Tajmir-Riahi ◽

Rodrigue Savoie

Keyword(s):

Dna Binding ◽

Spectroscopic Study ◽

Conformational Changes ◽

Binding Sites ◽

Calf Thymus Dna ◽

Raman Spectroscopic ◽

Raman Spectroscopic Study ◽

Dna Binding Sites ◽

Calf Thymus

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ИЗУЧЕНИЕ СТРУКТУРЫ ДНК В ПЛЕНКАХ МЕТОДОМ ИК-ФУРЬЕ-СПЕКТРОСКОПИИ

Биофизика ◽

10.31857/s0006302920060034 ◽

2020 ◽

Vol 65 (6) ◽

pp. 1058-1064

Author(s):

С.В. Пастон ◽

◽

А.М. Поляничко ◽

О.В. Шуленина ◽

Д.Н. Осинникова ◽

...

Keyword(s):

Molecular Weight ◽

Hydration Shell ◽

Aqueous Environment ◽

Ir Absorption ◽

Sodium Ions ◽

High Molecular Weight Dna ◽

Dna Hydration ◽

Na Ions ◽

Phosphate Groups ◽

Dna Film

The aqueous environment and ionic surrounding are the most important factors determining 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 water activity. In this work, we studied the B-A transition in high molecular weight DNA with a decrease of humidity in the film with different contents of Na+ ions using FTIR spectroscopy. The IR spectrum of DNA is not only very sensitive to the state of its secondary structure, but also allows us to estimate the amount of water bound to DNA. Upon dehydration of the DNA film, changes characteristic of the B-A transition were observed in the IR absorption spectrum. Using thermogravimetric analysis, it was shown that the degree of DNA hydration reaches the saturation level at a relative humidity of 60% and decreases slightly upon further drying. It has been established that with increasing Na+ concentration, the amount of water strongly bound to DNA decreases. Along with it, sodium ions destroy the hydration shell of DNA and are able to interact directly with phosphate groups.

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Infrared spectra of N-acetyl-L-α-amino-acid N'-methylamides with aliphatic side chains in non-polar solvents

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19810772 ◽

1981 ◽

Vol 46 (3) ◽

pp. 772-780 ◽

Cited By ~ 4

Author(s):

Jorga Smolíková ◽

Jan Pospíšek ◽

Karel Bláha

Keyword(s):

Amino Acid ◽

Conformational Changes ◽

Infrared Spectra ◽

Room Temperature ◽

Side Chains ◽

Polar Solvents

Infrared spectra of the L-alanine (I), L-leucine (II), L-valine (III) and L-tert-leucine (IV) N-acetyl N'-methylamides were measured. Amides I-IV are not self associated in tetrachlormethane in the concentration 2 . 10-5 mol l-1 at room temperature and in tetrachloroethylene in the concentration 1.5 . 10-4 mol l-1 at temperatures above 65° C. True conformational changes are observable only with the least flexible amide IV which exists at room temperature in a C5 conformation. This conformational type is also highly populated in the valine derivative III, but is less important in the alanine and leucine derivatives I and II in which the intramolecularly bonded C7 and the distorted hydrogen-nonbonded conformations contribute seriously.

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Swelling pressure and microstructure of an activated swelling clay with temperature

Clay Minerals ◽

10.1180/000985598545615 ◽

1998 ◽

Vol 33 (2) ◽

pp. 255-267 ◽

Cited By ~ 20

Author(s):

D. Tessier ◽

M. Dardaine ◽

A. Beaumont ◽

A. M. Jaunet

Keyword(s):

Room Temperature ◽

Swelling Pressure ◽

Radioactive Waste Disposal ◽

Basic Medium ◽

Hydraulic Pressure ◽

Swelling Behaviour ◽

Transmission Electron ◽

Ca Ions ◽

Na Ions ◽

Marked Drop

AbstractClay from Fourges has been selected by the Commissariat à l'Energie Atomique as a support in radioactive waste disposal studies. This material was activated by adding Na2CO3, then compacted at 60 MPa. Subsequently, its swelling behaviour was monitored at 90°C and 145°C for 330 days and at the end of this period the samples were examined by transmission electron microscopy (TEM). For this, they were embedded in a resin then sectioned with an ultramicrotome for mineralogical and chemical analyses. The initial material is essentially composed of kaolinite and smectite. Addition of Na2CO3 at room temperature induces a replacement of Ca ions by Na ions and the precipitation of finely divided carbonates on the surface of the constituents. At the end of 330 days at 90°C under a hydraulic pressure of 1 MPa, the initial particles combine and the material exerts a swelling pressure of 20 MPa. A complete reorganisation of the clay crystallites is observed without significant dissolution of the solid phases. After the same time at 145°C under a hydraulic pressure of 10 MPa, in a basic medium, the combined conditions are such that a high proportion of the clay is dissolved with formation of amorphous aluminosilicates correlated with a marked drop in the swelling pressure to 5 MPa. This work establishes the advantages of following the macroscopic properties in parallel with the microstructure variations for understanding the changes in the properties of clays.

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CsOH and its Lighter Homologues – a Comparison

Zeitschrift für Naturforschung B ◽

10.5560/znb.2014-4163 ◽

2014 ◽

Vol 69 (11-12) ◽

pp. 1229-1236

Author(s):

Matthias Wörsching ◽

Constantin Hoch

Keyword(s):

Gas Phase ◽

Room Temperature ◽

Structure Type ◽

Alkali Metal Hydroxide ◽

X Ray ◽

Raman Spectroscopic ◽

Cesium Hydroxide ◽

Free Ion ◽

The One ◽

First Time

Abstract Cesium hydroxide, CsOH, was for the first time characterised on the basis of single-crystal data. The structure is isotypic to the one of the room-temperature modification of NaOH and can be derived from the NaCl structure type thus allowing the comparison of all alkali metal hydroxide structures. Raman spectroscopic investigations show the hydroxide anion to behave almost as a free ion as in the gas phase. The X-ray investigations indicate possible H atom positions.

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In situ Raman Spectroscopic Observation of Polymer Chains in Semi-Crystalline Polyethylene Solids

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2020-1618 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Yusuke Hiejima ◽

Takumitsu Kida ◽

Koh-hei Nitta

Keyword(s):

Conformational Changes ◽

Tensile Elongation ◽

Spectroscopic Observation ◽

Polymer Chains ◽

Trans Conformation ◽

Raman Spectroscopic ◽

Higher Temperature ◽

Microscopic Origin ◽

Crystalline Polyethylene

AbstractIn situ Raman spectroscopy is applied for polyethylene solid under various environments to elucidate the morphological and conformational changes. The trans conformation retains up to higher temperature for high-density polyethylene, reflecting higher stability of the orthorhombic crystals composed of stacked trans chains. It is suggested that the conversion of the non-crystalline trans chains to the crystalline phase is the microscopic origin of thermal history in the crystallinity, whereas the transformation between the trans and gauche conformers is practically in thermal equilibrium. Microscopic and dynamic mechanism of deformation during uniaxial stretching is investigated for the molecular orientation and the microscopic load sharing on the crystalline and amorphous chains. Lower crystallinity results in smoother and higher orientation toward the stretching direction, as well as higher load on the amorphous chains, during tensile elongation.

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