Intermolecular interactions in solutions of serum albumin

The mechanisms of intermolecular protein complex formation were studied by the example of monomers, oligomers and aggregates of bovine serum albumin (BSA) depending on the protein concentration, pH and urea concentration. Using dynamic light scattering (DLS), analytical ultracentrifugation (AUC) and PAG electrophoresis we have shown the existence of dynamic equilibrium between monomers and aggregates in BSA solution. Decreasing pH of the solution (4.0–1.0) resulted in increasing sizes of the aggregates. In the solutions with low urea concentrations (below 2 M) the sizes of aggregates decreased, while higher urea concentrations (2–8 M) induced formation of larger aggregates due to the unfolding of the protein.     

Polyanionic inhibitors of HIV adsorption

The inhibitors of viral adsorption are a new generation of antiviral drugs, which can be used in the therapy of HIV infection. The review presents different classes of the HIV entry inhibitors, which are grouped according to the processes they are targeting: the interaction of the viral glycoprotein gp120 with the cell receptor CD4, the secondary interaction of gp120 with the chemokine receptors CCR5 or CXCR4, or the formation of the gp41 six-helix bundle required for the fusion of the virus with the cell membrane.     

On the laterocytic stomatotype in angiosperms

The laterocytic type of stomatal apparatus in angiosperms is considered. Investigation of the stomatal apparatus of 18 species of Hamamelidaceae, representing 15 genera, showed that in addition to the anomocytic, paracytic, and encyclocytic stomatotypes previously known in the family, the laterocytic type is found in several genera (Dicoryphe, Exbucklandia, and others). Study of 15 species of Chloranthaceae, representing all five genera, showed that laterocytic stomates occur inChloranthus andSarcandra and sometimesHedyosmum, along with stomates of other types.Barbeya oleoides (Barbeyaceae) and the four investigated species ofBalanops (Balanopaceae) have exclusively (or inB. oliviformis mainly) laterocytic stomates. Laterocytic stomates are present also inKadsura andSchisandra of the Schisandraceae, along with the previously known paracytic type. In addition to the foregoing genera, laterocytic stomates are known in some members of the Buxaceae, Celastraceae, Crypteroniaceae, Hydrangeaceae, Icacinaceae Platanaceae, Tetracentraceae and Trochodendraceae.     

Dynamics of parameters of energy metabolism at adaptation to diving in human

Studies of the diving reflex in comparative evolutionary terms have shown that a complex of reactions providing the oxygen-saving effect during diving is inherent in human as well as in the secondary-aquatic mammals. This is confirmed by study of peculiarities of energy metabolism the simulated diving (it is the breath holding with face immersed into the cold water—what we call the cold-hypoxic-hypercapnic effect, CHE). Data of gas analysis have shown that the oxygen consumption rate during the diving imitation is statistically significantly lower than during the usual expiration delay (Genche’s test). We have revealed that under effect of adaptation to CHE, on the background of a reduction of the total energy consumption by the organism there occurs a slight increase in contribution of aerobic processes to its energy supply. Adaptation to CHE has been shown to be accompanied by a decrease in reactivity of the parasympathetic chain of regulation of the heart chronotropic function and by an increase of duration of apnea. The apnea duration is directly correlated with level of insulin—the hormone stimulating activity of the anaerobic energy pathway provision. Under effect of adaptation to CHE there has been established an increase of the organism resistance to stress actions, which is confirmed by the lower levels of cortisol and thyroid hormones in representatives of the experimental group as compared with the control one.     

Cyclic GMP-induced structural transitions of photoreceptor membranes

The influence of cyclic GMP on the structural state of photoreceptor membranes was studied. The spin probe technique was used to obtain the dependences of microviscosity of lipid domains of membranes on cGMP concentration. It was shown that microviscosity of 5-doxylsteraric acid environment in rod outer segment, disc and plasma mambranes changed at concentrations of 2.10(7); 5.10(-6) and 6.10(-6). Non-cyclic GMP was ineffective. The ultrasound treatment of membraneous samples resulted on disappearance of the structural changes.     

Allele Polymorphism of a New Pentanucleotide STR Marker Located to an Intron of the Tumor Suppressor Gene ING1

Using polymerase chain reaction (PCR) DNA samples of unrelated subjects from the Volga-Ural region of Russia were examined to study allele polymorphism of the pentanucleotide repeat (TTGTG) _g localized to an intron of the tumor suppressor gene ING1. STR marker was registered in the EMBL database with the accession number AJ277387. In a sample of 119 individuals, three pentanucleotide alleles consisting of seven, eight, and nine repeated monomers were revealed. The allele frequencies were 0.24, 0.74, and 0.02, respectively. Heterozygosity was 0.45. On the basis of these data, the repeat can be regarded as a polymorphic STR marker for the ING1 gene and used in population and clinical studies.