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I G Kharitonenkov

Publications and source records attributed to I G Kharitonenkov.

116 records · Page 7Linked to original sources
PubMedDate not supplied

[Localization of the tryptophan residues of influenza virus matrix protein in reconstructed proteoliposomes: a fluorescent analysis].

Influenza virus matrix protein (M-protein) interaction with model phospholipid membranes, liposomes, was studied. Measuring of the effectiveness of energy transfer from M-protein triptophan residues to a fluorescent zond pyren included into the lipid phase of proteoliposomes was employed to assess the steric organization of the proteoliposome protein-lipid complex. A steric model is proposed in which M-protein molecules are located on the surface of lipid bilayer forming trimers. Analysis of pyren fluorescence proper demonstrated a strong influence of M-protein on the lipid bilayer structure: the viscosity of the lipid phase in the presence of M-protein was increased 2.3-fold.

Energy Transfer↗
PubMedDate not supplied

[Characteristics of isolating influenza virus hemagglutinin using purified bromelin].

Gel filtration and ion-exchange chromatography were used to isolate a fraction with the highest proteolytic activity and virtually lacking glycosidases from a commercial bromeline preparation ("Serva", grade B) showing, in addition to proteolytic, also glycosidase activity. The utilization of purified bromeline allows isolation of hemagglutinin without residual neuraminidase activity from influenza virus of various serotypes (H1, H1, and H3). The results are discussed on the basis of an assumption of analogous localization but different conformation accessibility of bromeline-sensitive parts of the light chains of influenza viruses of different subtypes, and a possible role of the carbohydrate component of surface glycoproteins, hemagglutinin and neuraminidase of influenza virus virions.

Bromelains↗
PubMedDate not supplied

[Influenza virus hemagglutinin: hydrodynamic properties and molecular weight].

Hydrodynamic properties of hemagglutinin isolated with bromelain from influenza virus were studied. The sedimentation constant determined by the method of analytical ultracentrifugation was 9.17 +/- 0.17 S. The translation diffusion coefficient estimated by the method of optic mixing spectroscopy comprised (3.6 +/- 0.1) X 10(+7) cm2/s. A comination of both the constants in Svedberg's equation allowed calculation of the hemagglutinin molecular weight (approximately 230,000) which suggests a three-subunit structure of the molecule. The hydrodynamic diameter and friction ratio of an isolated molecule were calculated.

Chemical Phenomena↗
PubMedDate not supplied

[Changes in the antigenic properties of influenza virus after sugar cleavage].

Concentrated and purified influenza A/PR/8/34 viruses was treated with a mixture of exoglycosidases for cleavage of carbohydrate part of surface glycoproteins. The hemagglutinating activity of the cleaved virus, its sorption properties, immunogenicity, and capacity to bind homologous antibody were studied. The virions devoid of sugars were shown to lose 50% of their hemagglutinating activity and to be less capable of forming virus-antibody complexes. At the same time the virus with cleaved glycoproteins retained its capacity to adsorb on nonorganic sorbent and stimulate antibody production in animals.

Adsorption↗
PubMedDate not supplied

[Relation between fluorescence and circular dichroism of the complex of the fluorescence probe 4-dimethylaminochalcone with serum albumin].

The fluorescence probe(4-dimethylaminochalcone; DMH) was noncovalently linked to human serum albumin (HSA). The variation of pH was due to serum albumin structural changes, which was determined in terms of DMH and HSA fluorescence and CD spectra. Considerable changes of fluorescence and CD spectra were observed at pH 8 and 10, where there is ionization of two more recently titrated tyrosin residues. It is assumed that these two tyrosine residues are in binding region and quench the fluorescence of DMH between pH 4 to 8. Quenching disappears if these residues are ionized (pH greater than 8) or if the protein undergoes the N -F transition (pH less than 4).

Chalcone↗
PubMedDate not supplied

[Optical measurements of nucleic acids in the presence of phenol and protein impurities].

Spectrophotometric method of determining the presence of phenol admixture in nucleic acid samples is presented. The method is based on determining the optical density ratio at 270 and 240 nm. This ratio is highly sensitive to the presence of phenol in solution. The method of determining nucleic acid concentration in the presence of phenol is also described. It is based on recording circular dichroism values at 265 nm for RNA and 275 nm for DNA. It is shown that the ratio of optical densities of nucleic acid samples at 260 and 280 nm is not a very sensitive criterion of the presence of proteins in solution. A much more sensitive characteristics is the ratio of circular dichroism values at 222 and 265 nm.

DNA↗