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N I Matveeva

Publications and source records attributed to N I Matveeva.

9 recordsLinked to original sources
PubMed1982

[Interaction of phospholipids with 3-oxosteroid-delta 1-dehydrogenase in adsorptional model biomembranes. Interaction of the enzyme from Mycobacterium rubrum with liposomes].

A comparative study of the activity of 3-oxosteroid-delta 1-dehydrogenase from Mycobacterium rubrum 121 in solution and after interaction with liposomes prepared from phospholipids of the same microorganism was carried out. It was demonstrated that at pH 6.6 the enzyme activity in the presence of liposomes is increased. The dependence of this effect on the amount of phospholipids and protein in the system, on the ratio and on the time of their coincubation was established. The activating effect of liposomes is not changed by Mg2+ or EDTA. The crucial role in the enzyme association with the phospholipid matrix belongs to electrostatic bonds which are destroyed upon increase in the ionic strength within the physiological range. The enzyme transition to the free state is accompanied by a fall in the activity. The possible role of these interactions in regulation of enzymatic activity in the cell is discussed.

Adsorption↗
PubMedDate not supplied

[Effect of monovalent anions of various nature on conformation of DNA molecules in a water-salt solution].

Methods of intrinsic viscosity [eta] and beam flow birefringence were used to study the effects of some single-charged ions (F-, Cl-, Br-, J-, NO2-, NO3-, ClO4-, SCN-, CH3COO-) on the size and thermodynamic rigidity of DNA molecule in aqueous solutions of sodium salts in a broad interval of ionic strength mu when temperature T is changed. It has been shown that the close interactions in a macromolecule and the resulting persistent length a of DNA are independent of the type of the salt anion over the whole interval of mu. On the contrary, specific volume of DNA molecule in solution, proportional to [eta] value, is quite sensitive to the anionic composition of a solvent which is due to the effect of anions and their hydration on the remote interactions in the macromolecule. The presence of polyatomic and halide anions is manifested differently in the [eta] value of DNA. Possible factors responsible for the observed effect and the role of structural alterations of water upon anion hydration are discussed.

Animals↗
PubMedDate not supplied

[Conformation of a DNA molecule in water-salt solutions depends on the salt anion type].

The methods of viscosimetry and flow birefringence were used to study the effect of anions F-, Cl-, Br-, J-, NO3-, ClO4-, SCN-, CH3COO- on the dimensions and thermodynamic rigidity of the DNA molecule in solutions in a wide range of ionic strengths and at different temperatures. It was shown that the persistent lengtH of DNA is independent of the anion type at all values of ionic strength, and the changes in its dimensions, which are determined from the changes in intrinsic viscosity, are due to the influence of anions and their hydration on long-range interactions in the macromolecule. Possible reasons for this phenomena and the role of structural changes in water upon hydration of anions are discussed.

Anions↗
PubMedDate not supplied

[Mycobacterium rubrum phospholipids].

Mycobacterium rubrum 121 cells contain 8% of lipids, one third of which is represented by phospholipids: cardiolipin, phosphatidyl ethanolamine, phosphatidyl inositol and phosphatidyl inositolmannosides. The acyl groups of these phospholipids are residues of C14-C19 fatty acids, with palmitic and oleic acids prevailing. Differences were found in the fatty acid composition of certain phospholipids.

Chromatography, Thin Layer↗