Macroscopic fluctuations of the kinetic activity of alcohol dehydrogenase

Macroscopic fluctuations of liver alcohol dehydrogenase enzymic activity in complex reaction consisting in ethanol oxidation and butyraldehyde reduction were studied. It was found that maximal fluctuation amplitude was observed when the rates of both reactions were equal. Such dependence indicates connection between macroscopic fluctuations in alcohol dehydrogenase reaction and oscillations of relative affinity of the enzyme to oxidized and reduced coenzyme forms.     

Immune reactions of Ornithodoros papillipes ticks (Argasidae) to the administration of different microorganisms

It has been shown that ticks possess cellular factors of organism protection which fulfil functions of seizure and digestion of different microorganisms in a way similar to phagocytosis. In response to the introduction of bacteria lysozyme quantity increases in tick's haemolymph that exerts a bactericide effect on the introduced strains Micrococcus lysodeikticus 2665, Staphilococcus aureus 209 and Salmonella typhimurium IT-2. When administering phage FX-174 into tick's haemolymph a persistence of phage particles during 1-2 months is observed. Specific antibodies developing in response to introduced phage corpuscles were not found.     

Enzymatic cleavage of superhelical DNA in a liquid crystal state]

Superhelical pBR322 DNA molecules form liquid-crystalline dispersions in water-salt solutions containing poly(ethyleneglycol). The formation of the liquid-crystalline dispersions from superhelical DNA molecules results in the appearance of two sites inside the DNA molecules that are split by Micrococcal nuclease. The first site of digestion does not differ from the standard site split by this enzyme in water-salt solutions, whereas the second one represents a new site specific only for the DNA molecules forming liquid-crystalline dispersions. Splitting of the DNA molecule through the first site is accompanied by formation of its linear form; splitting of a new site results in the formation of two linear DNA fragments with molecular masses equal to half of the initial DNA molecules. Enzyme digestion of superhelical DNA molecules forming liquid-crystalline dispersions induces a reformation of the "nonspecific" space organization of dispersions to the cholesteric one. A hypothetic model for packing of the superhelical DNA molecules inside liquid-crystalline dispersions and its transformation under enzyme action is suggested.     

"External chromophores" and intensive bands in circular dichroism spectra of liquid-crystalline microphases of nucleic acids

From the analysis of CD-spectra of liquid crystalline microphases formed from DNA molecules in complexes with "external chromophores" requirements are formulated for the compounds to be used in revealing peculiarities of spatial structure of nucleic acids liquid crystalline microphases. These requirements satisfied it is possible to record the CD-spectra having intensive bands in the regions of chromophores absorption. These bands prove the helical pattern of the spatial structure of nucleic acid liquid crystalline microphase.     

Compaction of 2-chain DNA as a method of procedure in determining its binding constant with antibiotics]

The binding of antibiotics and dyes with a compact form of DNA produced in water-salt solutions containing polyethylenglycol (PEG) presents a possibility of studying antibiotic interaction with DNA molecules contained in biological objects, such as viruses and chromosomes, since the compact form of DNA reflects some DNA properties in vivo. Possibly the use of the compact and not the "open" or linear form of DNA in chemical reactions will provide data on the efficiency of the compound "action" under conditions close to intracellular ones. The results well be useful in screening substances with "optimal" pharmacological effect. The paper presents a method for determination of the constant of antibiotic or dye binding with DNA and two-chain synthetic polynucleotides in water-salt solutions containing PEG. The method is based on "elimination" of the DNA molecules in the form of compact particles bound in a complex with an antibiotic or a dye. Comparison of the data with the results of estimation of the constants of antibiotic binding with DNA by the routine methods showed close conformity of the binding constants determined by different methods. It was found that the value of the binding constant of the antibiotics studied slightly depended on the structural state of DNA. The value was practically the same for the linear and the compact forms of DNA.     

Inheritance of Coat Color in the Mole Vole (<Emphasis Type="Italic">Ellobius talpinus</Emphasis> Pallas)

Based on the ecological features of the mole vole, family analysis of the inheritance of coat color was performed with the use of material collected in a wild population. Analysis of coat color in parents and offspring has demonstrated that the offspring segregation into black and nonblack animals after crosses of different types agrees with the hypothesis on the monogenic inheritance of these color variations. Black mole voles are homozygous for the recessive allele (genotype aa). Homozygotes for the dominant allele (AA) are brown. Heterozygotes (Aa) may be brown or have transitional color. The mean frequency of brown coat color in heterozygotes is 0.509 and is very variable. The higher the color intensity in black elements of parent coat color, the more is the offspring coat color saturated with these elements.     

The interaction between two charged rods in an electrolyte solution

A problem on the electrostatic interaction of two homogeneously charged macromolecular rods of a finite length, submerged into an electrolyte solution was considered. An explicit expression for the energy of interaction and rotational moment as a function of the angle of rotation between the long axes of the molecules was obtained. At small angles of rotation, the expression for energy turns into the corresponding formula for parallel rods, and the rotational moment tends to zero, as it follows from geometrical considerations. The possibility is discussed whether the study is applicable to real biological systems, including liquid-crystalline dispersions of DNA.     

Morphogenetic Effects of Resettlement of Mole Voles (<Emphasis Type="Italic">Ellobius talpinus</Emphasis> Pall., 1770) from the Southern Population to the Northern Boundary of the Species Range

Geometric morphometry has been used to reveal transformations of mandible morphogenesis in the offspring of mole voles resettled to the northern part of the species range from a southern population. The transformations were new compared to both the original (southern) and the aboriginal (northern) populations. A significant increase in the intragroup morphological disparity estimated by the mean nearest neighbor distance (MNND) in the resettled animals compared to both aboriginal populations is an indirect indication of an increased developmental instability in the resettled animals exposed to new climatic conditions.     

Macroscopic fluctuations in the alcohol dehydrogenase reaction

When studying alcohol dehydrogenase reaction spontaneous oscillations of reaction rate were revealed. The value of these fluctuations essentially exceeded measuring error. The fluctuation amplitude had the maximum value when minimum buffer concentrations were used. Distribution of fluctuations according to their values was polymodal in all experiments. These oscillations seem to be classified as "macroscopic fluctuations" which have been revealed by S. Shnoll & coll [3].