[Isotopic effects of low concentration of deuterium in water on biological systems].

Isotopic effects of deuterium in water are studied in a broad range of concentrations on a number of biological objects of different organization levels. The results obtained show that biological objects are sensitive to variations of isotope composition in water. A decrease or increase in deuterium concentrations in water may cause activation or inhibition of biological functions. The values of biological isotopic effects of low deuterium concentration may even be higher than those of high deuterium concentration. No regularity in response for all the objects studied failed to find out in a range of deuterium concentration in water from 4 ppm to 1%.

[Distribution of internal parameters of protein hydration shell structure].

Valence and torsion angles distribution was obtained by computer simulation for protein hydration shell and bulk water. These distributions were analyzed. Hydration shell and bulk water have different distributions and we explain it in terms of topology.

[Computer modeling of parametric structures of water].

The algorithm for the arrangement of hydrogen atoms in twist-hexacycle parametric structures of bound water is developed. The calculation of energetic properties is carried out using the TIP3P and Poltev-Malenkov potentials. Optimization of energy for these structures is fulfilled.

[Structure of bound water and topological rearrangement waves].

The evolutionary conception of bound water and the structure of liquid water has been briefly described. The function of the radial distribution of water molecules has been analyzed. The intermediate maxima at 0.35 nm of the function is shown to be described in the frame of the model of continuous hydrogen bond net without invoking the mixed and two-state models of liquid water. Using a simple extensive parametric structure, spiral 30/11, a model of topological rearrangement waves including bifurcate bonds is suggested. These waves can transmit the information on conformational transitions between cellular elements through the virtual spirals of bound water.

[Luminescence of aqueous solutions of glycine and its N-methyl derivatives].

A nonmonotonous dependence of luminescence intensity of aqueous solutions of 0.1 M glycine and its N-methyl derivatives on the number of methyl groups in the solute molecule was found. A correlation between luminescence intensities and optical density at the excitation wavelength of 300 nm was revealed. Possible causes of the phenomenon observed were analyzed. Among these are: luminescence of admixtures, intrinsic luminescence of dissolved molecules, and luminescence related to the formation of nanoscale complexes in solution. On the basis of the data, it is impossible to make a final choice between the three above-mentioned mechanisms of luminescence of aqueous solutions of glycine and its N-methyl derivatives.

[An experimental study of potentiated aqueous solutions].

A systematic study was undertaken of luminescent aqueous solutions of homeopathic preparation of sodium chloride at a dilution from D1 to D30, produced by "Weleda" company (Moscow) was carried out. It was shown that intensity of luminescence versus the degree of dilution is a non-monotonous function with several maxima, the main maximum corresponds to 13-14 decimal dilution. The dynamics of spectra was registered for several weeks. A systematic study of water samples (D1-D30) exposed to a similar procedure of potentization but without salt addition was also performed. The difference in the luminescence spectra of water of different stages of potentization was shown. The motility of infusoria Spirostoma ambiquum in solutions being examined was studied. A significant negative correlation between the infusoria motility and luminescence intensity was registered.

[Physico-chemical properties of aqueous solutions, prepared in a membrane electrolyzer]. / Fiziko-khimicheskie svoistva vodnykh rastvorov, poluchennykh v membrannom élektrolizere.

The physicochemical properties of aqueous solutions resulting from membrane electrolysis were studied. It was shown that the catholyte contains hydrogen peroxide at a concentration of 10(-7), which is formed during the reduction of soluble oxygen. It was found that the relaxation of the catholyte redox potential is caused by the transition of the reducing agent to the gaseous phase. The relaxation characteristics of the redox potentials of the catholyte and molecular hydrogen solution were compared. The similarity of the relaxation characteristics of the catholyte and the hydrogen solution as well as the fact that the catholyte, despite its low redox potential, does not reduce either potassium ferricyanide or 5-5'-dithiobis(2-nitrobenzoic acid) support the suggestion that the redox potential of the catholyte is due to molecular hydrogen. However, based on this suggestion, it is impossible to explain the increase in the relaxation time of the catholyte with increasing ionic strength and the fact that, as the redox potential of the catholyte decreases, the concentration of other gases dissolved in the catholyte remains unchanged. Thus, the question regarding the nature of the reducing agent remains open.

[Specificity of bacterial response to variation of isotopic composition of water]. / Spetsifichnost' otklika bakterii na variatsii izotopnogo sostava vody.

Culture growth of bacteria with different membrane lipid composition was studied in liquid media with different isotope content of water. The concentration of deuterium in water was varied from 0.01 to 90%. It was shown that large concentrations of deuterium cause the inhibition of all cultures except Deinococcus radiodurans, the most stable living cell. Two cultures, Methylobacterium organophilum and Hyphomonas jannaschiana, showed a pronounced activation at a deuterium concentration of 0.01%. At higher deuterium concentrations, the inhibition of culture growth was observed. The strains Renobacter vacuolatum, Arcocella aquatica NO502 and Caulobacter crescentus did not show any significant effect at low concentrations of deuterium.

Effect of polylysine on transformations and permeability of negative vesicular membranes.

Small (40-60 nm in diameter) and large (300-350 nm) negative vesicles were complexed with a cationic polypeptide, poly-L-lysine (PL). Laser microelectrophoresis experiments showed that in small vesicles rendered anionic with the addition of cardiolipin (CL(2-)), only the CL(2-) in the outer leaflet is involved in the complexation with PL. Calorimetric and other data demonstrate that the binding of PL to the membrane surface causes domains ("rafts") of CL(2-) to form in the outer leaflet, and it is these domains that electrostatically bind the polymer. The kinetics of transmembrane permeation of doxorubicin (Dox, a fluorescent anti-tumor drug) was monitored with and without PL binding to the outer surface of the vesicles. It was found that PL mediates the permeation of Dox into the vesicle interior. In the absence of PL, the Dox molecule (possessing an amino group of pK(a)=8.6) binds to the anionic vesicles in the protonated form and, consequently, suffers an impaired mobility through the membrane. On the other hand, when the PL covers the vesicle surface, Dox passes though the membrane with greater ease. The effects of salt and polyanion on the stability of PL-vesicle complexes and the PL-mediated Dox permeation are also discussed.

[Computer module design of the parametric structure of water]. / Komp'iuternyi modul'nyi dizain parametricheskikh struktur vody.

The algorithms of module design and the results of constructing the parametric structures of water were considered. The tetrahedral electron structure of the oxygen atom of water, which is a double symmetric donor and acceptor of protons, was taken as the main postulate. As opposed to the crystal lattices of diamond and ice, the hexacycle twist-bath was considered as the basic element of the original structure. A great variety of possible structures were obtained, which involve quasi-unidimensional (helices, rods), dendrite-like, ring-shaped, planar, and fractal structures, as well as combinatoric structures composed of these forms. The functions of distribution of valence angles in fractal structures optimized with respect to energy have two main maxima at 104 and 112 degrees, as differentiated from the starting ideal tetrahedral angle of 109.5 degrees. Changes in, and the accumulation of elastic energy of distortions of rod structure of different symmetry were analyzed. This energy can be utilized during the conformational changes of biopolymers. The substantial difference in the solubility of two anomeric forms of glucose is explained by a different degree of conformity of the glucose molecule structure to the structure of bound water.

Reversibility of structural rearrangements in the negative vesicular membrane upon electrostatic adsorption/desorption of the polycation.

Interaction of small unilamellar vesicles (SUVs), composed of negative diphosphatidylglycerol (cardiolipin, CL(2-)) and neutral dipalmitoylphosphatidylcholine (DPPC), with poly(N-ethyl-4-vinylpyridinium bromide) (PEVP) was studied in water solution above and below the vesicular membrane melting point by means of differential scanning calorimetry, photon correlation spectroscopy, microelectrophoresis, conductometry, and fluorescence techniques. It has been found that CL(2-) species are homogeneously distributed within DPPC-CL(2-) SUV membrane leaflets and between them. Interaction of PEVP with DPPC-CL(2-) SUVs led to drastic structural rearrangements in the membrane if it was in the fluid state (liquid SUVs). Negative CL(2-) molecules migrated from the inner to the outer membrane leaflet and segregated in the vicinity of adsorbed PEVP chains. In addition, PEVP adsorption terminated completely the exchange of lipid molecules between the SUVs. At the same time, the integrity of liquid SUVs contacting PEVP remained unchanged. Since the interaction of PEVP with liquid SUVs was predominantly electrostatic in nature, the polycation could be completely removed from the vesicular membrane by addition of an excess of polyacrylic acid (PAA) polyanions forming a more stable electrostatic complex with PEVP. Removal of PEVP resulted in complete resumption of the original distribution of lipids in lateral and transmembrane directions as well as intervesicular lipid exchange. In contrast, PEVP interacting with DPPC-CL(2-) SUVs formed defects in the vesicular membrane if it was in the gel state (solid SUVs). Such interaction was contributed not only by electrostatic but most likely by hydrophobic interactions involving the defected membrane sites. PEVP kept contacting solid SUVs in the presence of an abundant amount of PAA. The established phenomena may be important for understanding the biological effects of polycations.

[Nonequilibrium state of electrochemically activated water and its biological activity]. / Neravnovesnoe sostoianie élektrokhimicheski aktivirovannoi vody i ee biologicheskaia aktivnost'.

Changes in the physicochemical parameters (pH, redox potential and electroconductivity) of catholyte and anolyte produced by membrane electrolysis of distilled water and dilute (c < 10(-3) M) sodium chloride solutions were studied. The relaxation of these parameters after electrolysis and the influence of catholyte and anolyte on the growth of roots of Tradescantia viridis grafts, the development of duckweed, and the motive activity of infusoria Spirostomum ambiguum were investigated. It was found that the anolyte of distilled water stimulated development of these biological objects. The direction of shift of physicochemical parameters of catholyte and anolyte from equilibrium values and the type of their biological activity (stimulation or inhibition) depend on salt concentration in initial solution. Barbotage of initial distilled water with argon or nitrogen leads to a greater decrease in the redox potential of catholyte during electrolysis. The physicochemical parameters relax to equilibrium values, and the biological activity of catholite and anolyte decreases with time and practically disappears by the end of the day. It was found that the oxidation of reducing agent by atmospheric oxygen is not the sole cause of the relaxation of catalyte redox potential. The increase in the ionic strength of catholite and anolyte by the addition of concentrated sodium chloride after electrolysis decreases the rate of redox potential relaxation several times. The redox potential can be maintained for long periods by freezing.

Adsorption of polyvalent cations to bilayer membranes from negatively charged lipid: estimating the lipid accessibility in the case of complete binding.

The effect of trivalent (Gd(3+) and Yb(3+)) and divalent (Be(2+) and Ca(2+)) cations on suspensions of multilamellar liposomes formed from brain PS and DMPS has been studied using microelectrophoresis and DSC techniques, respectively. The zeta potential values have been shown to strongly depend on the total lipid concentration in the suspension. At moderate concentrations of the polyvalent cations, the total cation concentration exceeds the bulk one several times due to adsorption of cations to the liposomes. A modification of the Gouy-Chapman-Stern theory in the case of unknown bulk concentration of the polyvalent cation is presented. An intrinsic association constant for Be(2+) ions was evaluated to be about K(2) approximately 50 M(-1). The algorithm for estimating the concentrations of the accessible (to exogenously added polyvalent cations) lipid-binding sites is described. These values are consistent with the subsurface concentrations of the polyvalent cations, which monotonously increase with the total concentration of the polyvalent cations. The calculated lipid accessibilities are shown to be in accordance with the DSC data.

Reversibility of structural rearrangements in lipid membranes induced by adsorption-desorption of a polycation.

Interaction of poly(N-ethyl-4-vinylpyridinium bromide) with mixed cardiolipin/phosphatidyl-choline (1/9) liposomes was studied by differential scanning calorimetry and photon correlation spectroscopy. It was found that the adsorption of polycation on the surface of liquid liposomes was accompanied by transmembrane migration of negatively charged cardiolipin molecules from the inner to outer membrane leaflet and lateral lipid segregation. At the same time, the liposome integrity was retained, and the adsorbed polycation can be displaced from the membrane by recomplexation with polyanions. As a result, the initial transmembrane and lateral lipid distribution in the membrane was restored.

[Features of the effect of ammonium ion on the enzymatic activity of myosin and subfragment-1]. / Osobennosti vliianiia iona ammoniia na fermentativnuiu aktivnost' miozina i subfragmenta-1.

The kinetic isotope effect of hydrolysis of ATP by myosin subfragment-I in the presence of K+, NH4+, Rb+ was measured. VH/VD was found to be 1.8; 1.3; 2.0, respectively. According to the thermodynamic isotope effect induced by hydration, the kinetic isotope effect must increase with the increase of cation size from K+ to Rb+. The size of ammonium ions is the intermediate between K+ and Rb+, but the observed isotope effect in the presence of ammonium is much lower than in the presence of K+ and Rb+. The results suggest that monovalent cations occur near the active center of the enzyme and contribute to some extent to the hydrolysis reaction but the specificity of ammonium ions seems not to be due to its ideal steric accordance. The obtained results support the viewpoint that NH4+ ions as donor of protons participate in the chemical stage of ATP hydrolysis by subfragment-I.

[Modulation of the intensity of fluorescence of aqueous solutions of proteins by magnetic field]. / Moduliatsiia intensivnosti fluorestsentsii vodnykh rastvorov belkov magnitnym polem.

Effect of the constant magnetic field with up to 3.2 X 10(-4) A/m intensity on the fluorescence of papain aqueous solutions was investigated. It has been shown that depending on the magnetic field direction a reversible decrease or increase of fluorescence intensity takes place. The variation of fluorescence intensity under the influence of magnetic field is maximal under excitation at long wave ultra-violet light. The effect increases with the increase of temperature, increases linearly with the increase of magnetic field intensity but doesn't depend on protein concentration in diluted solutions. The examination of the data leads to the conclusion on the existence of two possible mechanisms: the variation of properties of surface tryptophan residues environment and paramagnetic orientation of protein globule under the influence of a magnetic field.

[Changes in mechanical characteristics of immobilized crystals and films of globular proteins during substitution of D2O for H2O]. / Izmenenie mekhanicheskikh kharakteristik immobilizovannykh kristallov i plenok globuliarnykh belkov pri zamene H2O na D2O.

The influence of substitution of the isotopic composition of the medium on the mechanical properties of immobilized crystals and films from bovine pancreatic ribonuclease and hen egg white lysozyme was investigated. The order of magnitude of the observed effects indicates that the contribution of the electrostatic interaction to the observed isotopic effect may be considered inessential. The absence of aggregation in the H2O and D2O medium under experimental conditions is demonstrated by the method of the low angle dispersion of X-rays. The observed effects of D2O on the mechanical behavior of crystals and films of proteins may be accounted for by the strengthening of molecular interactions in the samples.

[Relation between the lipid composition and changes in the compressibility of phospholipid monolayers caused by substitution of H2O with D2O]. / Sviaz' lipidnogo sostava s izmeneniem szhimaemosti monosloev fosfolipidov pri zameshchenii H2O na D2O.

Compressibility of monolayers of dipalmitoyl phosphatidyl choline, dimyristoyl phosphatidyl choline, egg lecithin, triolein, azolectine, phosphatidyl serine and total brain lipids formed on air--H2O or air--D2O interfaces is investigated.

[Analysis of kinetic isotope effects in H2O-D2O mixtures in enzymatic catalysis: detection of conformation-dynamic processes]. / Analiz kineticheskikh izotopnykh éffektov v smesiakh H2O-D20 pri fermentativnom katalize: vyiavlenie konformatsionno-dinamicheskikh protsessov.

An analysis was carried out of Gross-Butler type equations describing relationship between deuterium isotope effect in reactions with proton transfer and deuterium concentration in the medium. It has been shown that with all possible coefficient values of isotopic fractionation of enzyme functional group protons the shape of indicated relationships qualitatively differs from the experimentally observed one for myosin hydrolysis of ATP. This discrepancy as well as uniform nonlinear change of myosin denaturation temperature and of kinetic isotope effect in myosin hydrolysis of ATP on deuterium fraction in solution give evidence of D2O effect as a solvent and point to an essential role of conformational - dynamic processes in the course of enzymic catalysis with myosin.