[Production of timolol containing calcium-phosphate nanoparticles and evaluation of their effect on intraocular pressure in experiment].

Methodology for production of calcium-phosphate nanoparticles is developed and its efficacy as a drug carrier system is estimated by example of timolol. Conditions for production of particles with optimal size and resistance are determined, methodology of loading of particles with timolol is developed. Physical parameters of particles (form, size, relief), kinetics of saturation with drug and its release are studied.

[The properties of the Pseudomonas aeruginosa bacteriophage phiPMG1].

The properties of the isolated Pseudomonas aeruginosa bacteriophage phiPMG1 include the lytic infection cycle, and the formation of a broad halo (semi-transparent zone) around the plaques. We consider phiPMG1 as a potential member of therapeutic cocktails of live phages, and as a source of peptidoglycan and lipopolysaccharide degrading enzymes. Partial sequencing of phiPMG1 genome has revealed high similarity with known temperate P.

[Development of Streptococcus pyogenes cells inactivation for turbidimetric determination of bacteriolytic activity of phage-associated enzyme].

Aim: Development a method of treatment of Streptococcus pyogenes bacteria that does not disrupt the integrity of surface structure of cell and provides optimal reproducibility of enzyme preparation activity test results.

Materials And Methods: Museum cultures of S. pyogenes M29 and S.

[Design of the composition of baculovirus agents].

The ability of 30 compounds to protect infection bacteria and baculoviruses from the damaging effect of ultraviolet (UV) irradiation was investigated. For this B. thuringiensis var.

[Bacteriophage enzymes for the prevention and treatment of bacterial infections: stability and stabilization of the Streptococcus pyogenes cell lysing enzyme].

The effect of various compounds on the activity and stability of a phage-associated enzyme lysing cells of streptococci of groups A and C (PlyC) was investigated. Substantial inhibition of the enzyme activity was revealed at an increased ionic strength (in the presence of NaCl) and upon the addition of carbohydrates (mono-, di-, and polysaccharides), i.e.

[Effect of chemical modification of lipase on the regulation of its lipolytic activity in reversed micelles].

Hydrophilized and hydrophobized forms of the lipase from Mucor miehei were obtained by its chemical modification with cellobiose and N-hydroxysuccinimidyl palmitate with a modification degree of 4 in both cases. A comparative analysis of the regulation of the catalytic activities of the native and modified lipases was carried out in the system of reversed micelles of OT aerosol (AOT) in isooctane. The level of catalytic activity of all the lipase preparations in the micellar medium was found to be higher than that in aqueous solution.

[The lipase/lipoxygenase bienzyme system in AOT reversed micelles in octane].

In this work it is shown that the bienzyme lipase/lipoxygenase system can function in reversed micelles of bis(2-ethyl)hexyl sulfosuccinate (AOT) in octane. As a lipase substrate, a fish fat preparation (fat of sea mammals) with a high content of polyunsaturated fatty acids was used. It was demonstrated that the bienzyme reaction proceeded in a stationary mode and had a rate-limiting step catalyzed by lipase.

[Synthesis of alkyl glycosides, catalyzed by beta-glycosidases in a reversed micelle system].

A basic possibility of enzymic synthesis of alkyl glycosides in a system of the Aerosol-OT (AOT) reverse micelles was studied. Octyl beta-D-galactopyranoside and octyl beta-D-glucopyranoside were synthesized from the corresponding sugars (lactose or glucose) and octyl alcohol under catalysis with glycolytic enzymes, beta-galactosidase and beta-glucosidase, respectively. The transglycosylation/hydrolysis ratio was shifted toward transglycosylation by using octyl alcohol, one of the substrates, as an organic solvent.

[Regulation of the supramolecular structure and catalytic activity of D-glyceraldehyde-3-phosphate dehydrogenase in systems of reversed Aerosol OT micelles in octane].

Reversible formation of various oligomeric forms of rabbit skeletal muscle D-glyceraldehyde-3-phosphate dehydrogenase (GAPD) in reversed micelles of Aerosol OT in octane at variable degrees of hydration (size) of the micelles, has been demonstrated. All the oligomeric forms of the enzyme possess a catalytic activity in the reversed micelle system. Data from the sedimentation analysis provide evidence for the formation of a monomer, a dimer and a tetramer of GAPD.

[Penicillin acylase from Escherichia coli: catalytically active subunits].

Gel filtration under denaturing conditions was used to isolate the alpha- and beta-subunits of penicillin acylase (PA). Refolded subunits were obtained through removing urea by dialysis. Both renatured subunits were catalytically active during hydrolysis of phenylacetic acid p-nitroanilide; this activity decreased after addition of a serine-specific inhibitor--phenylmethanesulfonyl fluoride.

[Regulation of the catalytic activity and supermolecular structure of penicillin acylase from Escherichia coli in an aerosol OT reversed micelle system in octane].

The properties of penicillin acylase from E. coli solubilized by hydrated reversed micelles of Aerozol OT (AOT) in octane were studied. The catalytic activity dependence on the hydration degree, a parameter which determines the size of the micelle inner cavity, represents a curve with three optima, each corresponding to the enzyme functioning either in a dimer form (omega 0 = 23) or in the form of separate subunits--heavy, beta, and light, alpha, at omega 0 = 20 and 14, respectively.

[Artificial oligomerization of enzymes--a new way of regulating their catalytic activity in reversed micellar systems].

Comparative studies were carried out in the catalytic activity regulation of native alpha-chymotrypsin and its artificially produced hexameric form as an example of non-dissociating oligomeric enzyme (covalently cross-linked by means of succinimidyl-3-(2-pyridylthiopropionate] in the Aerosol OT reversed micelles in octane. Native (monomeric) alpha-chymotrypsin exhibits maximal catalytic activity in the reversed micelles at the hydration degree w0 = 10, when the radius of the micelle inner cavity is equal to the radius of the alpha-chymotrypsin globule. For the alpha-chymotrypsin hexamer, optimum is observed at w0 = 45, with the inner micellar cavity radius (r = 68 A) being approximately equal to the radius of the sphere surrounding the octahedral combination of the six monomeric alpha-chymotrypsin molecules (r = 61 A).

[Alkaline phosphatase in reverse micelles of surfactants in organic solvent].

A dimeric enzyme (alkaline phosphatase from calf intestinal mucosa) was studied in the reversed micellar medium of Aerosol OT (AOT) in octane. The dependence of the enzyme's activity on the hydration degree (on the size of micelles) is a curve with two optima corresponding to the hydration degrees [H2O]/[AOT] = 17 and 25; when the inner cavity radii of reversed micelles are equal to the size of the enzyme's monomer (Mr = 70 000) and of the dimer (Mr = 140 000). Ultracentrifugation experiments showed that a reversible dissociation of the enzyme into subunits takes place as a result of the change of the hydration degree; the first and second maxima corresponding to the functioning of the monomeric and dimeric forms of the enzyme, respectively.

[Comparative study of the regulation of catalytic activity of soluble and membrane forms of enzymes in reverse micellar systems. Gamma-glutamyltransferase and aminopeptidase].

The regulations of functioning of water soluble and membrane forms of enzymes in the systems of reversed micelles of surfactants in organic solvents are compared. By an examples of gamma-glutamyltransferase (in AOT reversed micelles in octane) and amino-peptidase (in Brij 96 reversed micelles in cyclohexane) the principal difference in the catalytic activity regulation of water soluble and membrane forms is demonstrated. The catalytic activity of the membrane form depends largely on the surfactant concentration at the constant hydration degree, whereas the activity of the water soluble form is constant under these conditions.

[Interconnection between activity and conformational mobility of alpha-chymotrypsin in reverse micelle systems].

A comparative study of the catalytic activity of alpha-chymotrypsin and the spin label rotation frequency in the alpha-chymotrypsin active center of reverse micellar systems solvated by H2O-organic mixtures was carried out. It was found that the decrease in the label rotation frequency resulting from the substitution of water in the micellar inner cavity by glycerol, 2.3-butanediol and dimethylsulfoxide (up to 95%) caused a marked increase (20-fold in the case of 2.

[A new approach to titrating active enzyme centers upon the use of surface-active micellar substances in organic solvents].

Micellar solutions of surfactant in organic solvents with rubber additions are proposed for determination of active enzyme concentration. A kinetic theory of enzymatic reactions in reversed micellar systems is developed, suggesting the intermicellar transport of the substrate to be the limiting step in viscous medium. Under these conditions, it is shown that fraction of the product formed after quick transformation of the substrate located in the enzyme-containing micelles depends upon active enzyme concentration and aggregation number of surfactant molecules.

[Relaxation phenomena in systems of protein-containing reverse micelles of surfactants in organic solvents].

The research was aimed to establish the equilibrium processes in protein-containing systems of AOT reverse micelles in octane. As chromophore label for tracing the kinetics of the process, the acid-base indicator, p-nitrophenol, was used. The establishing of the equilibrium in the reverse micelle system notably decelerated in the presence of a solubilized protein (native and stearoylated alpha-chymotrypsin).

[Conformation and reduction-oxidation properties of cytochrome c incorporated into reversed micelles of a surfactant in an organic solvent].

Changes observed in CD- and absorption spectra of cytochrome c solubilized in reversed micelles AOT showed significant structural transformations of protein in the region of the active centre and particularly revealed a replacement of the sixth ligand of heme iron. These changes also affected the redox properties of cytochrome c.

[Catalysis by enzymes entrapped into reversed micelles of surfactants in organic solvents. Peroxidase in the aerosol OT-water-octane system].

Spectral and catalytic parameters of peroxidase solubilized in the aerosol OT-water-octane system have been studied. The spectrum of peroxidase solubilized in octane with AOT reversed micelles, a degree of surfactant hydration being above 12, is actually identical to that of the enzyme aqueous solution. On the other hand, significant spectral changes have been detected when transferring the enzyme from water to the reversed micelle medium at low degrees of surfactant hydration, precisely [H2O]/[AOT] less than 12.

[Enzymes incorporated into reversed micelles of surfactants in organic solvents. Study of the protein-aerosol OT-H2O-octane system by sedimentation analysis].

Using ultracentrifugation, the systems of reversed micelles of aerosol OT in octane containing solubilized protein (alpha-chymotrypsin, lysozyme, trypsin, egg albumin, alcohol dehydrogenase from horse liver and gamma-globulin) were studied. The changes in the sedimentation coefficients of reversed micelles during incorporation of the protein are correlated (within a wide range of experimental conditions, e. g.