Search PubMed⌕ Search

Biomedical subjects

G V Samsonov

Publications and source records attributed to G V Samsonov.

66 records · Page 4Linked to original sources
PubMedDate not supplied

[Isolation and study of physico-chemical properties of alpha-amylase from Bacillus subtilis].

By chromatography on ultragel ACA-54 alpha-amylase was isolated from the enzymic preparation amylosubtilin G10x. As compared to the initial preparation, the specific activity of the purified enzyme per mg increased 25-fold. The major physico-chemical characteristics of alpha-amylase were determined. The molecular weight of the enzyme measured by gel-chromatography and electrophoresis was estimated to be 49,000. The isoelectric point determined by electrofocusing was found to be 5,2. Irreversible acid inactivation of the enzyme in the range of pH 2-5 was investigated. The reaction was found to develop in at least two stages.

Amylases↗
PubMedDate not supplied

[Reversibility of the acid inactivation of immobilized alpha-amylase].

The process of reactivation of acid-inactivated alpha-amylase of Bacillus subtilis in weakly alkaline media was examined. The reactivation of alpha-amylase immobilized on carboxyl polyelectrolytes developed in a larger measure than that of the native enzyme. The stabilizing effect of the cross polymer decreased as its porosity increased.

Bacillus subtilis↗
PubMedDate not supplied

[Analysis of the secondary structure of urokinase by the circular dichroism method].

The secondary structure of urokinase with molecular weight 33 000 dalton was studied by the circular dichroism method. The secondary structure parameters were calculated based on the protein reference CD spectra resulted in the following secondary structure parameters: approximately 30% aminoacid residues constitute the alpha-helical regions, the same amount forms the beta-structure and an essential fractions contributes the beta-turns. Conformational stability of urokinase to alkaline pH (up to 11.6) and high temperature (up to 80 degrees) in 0.1 M phosphate buffer pH 6.6 was found.

Circular Dichroism↗
PubMedDate not supplied

[Effect of FAF anionite swelling on its sorption properties].

Experiments were carried out to clarify the effect of swelling coefficients of various samples of the polycondensation anion exchange resin FAF in the C1 form on its sorption properties. The anion exchange resin was used to eliminate contaminating proteins and low molecular weight agents from the allantois fluid and liver cultured cells of pigs. Thermal treatment of the anion exchange resin increased the coefficient of its swelling, leaving the structure unchanged. The resin structure was controlled by electron microscopy and X-ray scattering of low angle. When the resin samples with the swelling coefficients of 3.5 and 4.0 were used, 30-40% of proteins, 50% of reducing agents and neutral carbohydrates and a small quantity of phosphorus were adsorbed.

Adsorption↗
PubMedDate not supplied

[Use of microdispersed forms of crosslinked polyelectrolytes in biotechnology].

The interaction of microdispersions of crosslinked polyelectrolytes with ions of biologically active substances has been studied by physicochemical methods. The processes of ion exchange and physical adsorption, underlying the interaction, can promote flocculation. Of particular importance is the selective flocculation of dipolar ions of biologically active substances.

Biological Factors↗
PubMedDate not supplied

[Ion exchange purification of some enzymes on KMT carboxyl cation exchanges].

Highly purfied preparations of the enzymes--yeast beta-fructofuranosidase, fungal beta-galactosidase and bacterial proteases have been isolated from crude preparations or culture liquids by adsorption on KMT microporous carboxyl cation exchanger. During desorption the enzyme activity has fully recovered and the specific activity increased 4.5-fold for beta-galactosidase and 54-fold for proteases.

Bacillus subtilis↗
PubMedDate not supplied

[Combination of the sieve effect and ion exchange chromatography during isolation of recombinant alpha2-interferon on the cellosorbent CS KU-23].

Preliminary purification of alpha 2-interferon from the culture liquid on cation-exchange sorbents was studied. Application of a cellosorbent based on the cationite KU-23 resulted in a 20-25-fold purification of recombinant alpha 2-interferon in a one-step process as a result of combination of the sieve effect and ion-exchange chromatography.

Cellulose↗
PubMedDate not supplied

[Effect of the kinetic selectivity of eremomycin adsorption on the concentration of components in chromatographic bands].

The adsorption dynamics of antibiotic eremomycin to structurally segregated carboxylic adsorbents was studied. It was shown that effects of the kinetic selectivity of adsorption lead to an additional narrowing of bands containing the component to be separated. This narrowing provides the possibility of superpurification of biologically active compounds by the "small shift" method of quasiequilibrium chromatography.

Adsorption↗
PubMedDate not supplied

[Preparation and properties of trypsin modified by polysaccharides].

Trypsin modified by dextran preactivated with 2-amino-4,6-dichloro-1,3,5-triazine or ethyl chloroformate has been prepared. Properties of the resulting conjugates with respect to hydrolysis of synthetic substrates--methyl ester benzoyl L-arginine and n-nitrophenyl ester of n'-guanidine benzoic acid as well as high molecular weight substrates--casein and fibrin--have been studied. Stability of conjugates during autolysis and irreversible heat denaturation has been investigated.

Enzyme Activation↗
PubMedDate not supplied

[Frontal displacement chromatography of melittin on meshed polymer ionites].

Conditions of frontal displacement chromatography were optimized for preparative purification of the polypeptide hormone melittin from bee venom. Melittin was purified to an extent higher than that of a standard preparation described in the biochemical literature.

Chromatography, High Pressure Liquid↗
PubMedDate not supplied

[Catalase inactivation during storage in solution and its stabilization by polysaccharides of microbial origin].

It has been experimentally shown that the rate of inactivation of pure catalase in solution does not obey the kinetics of the first order. The kinetics of denaturation taking into account partial stabilization of catalase due to the formation of intermolecular complexes of native molecules with denatured molecules has been derived. Using the equation, the rate of catalase inativation during storage in pure solutions has been calculated from the experimental data. Polysaccharides of microbial origin can also stabilize catalase. The kinetics of catalase inactivation in the system where the enzyme and polysaccharide forms a reversibly dissociating complex has been described.

Catalase↗