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1.
Acta Naturae ; 13(4): 47-52, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35127146

RESUMO

Elevated levels of apoB-100 containing lipoproteins and markers of systemic inflammation are often observed in patients with cardiovascular diseases. The concentrations can be reduced by pharmacotherapy or extracorporeal treatment. The sorbent, which removes CRP and atherogenic lipoproteins, simultaneously reduces the bloodstream concentration of these components. The efficacy and selectivity of the designed sorbent were studied, desorption constants of CRP (Kd = 4.2 × 10-8 M) and LDL (Kd = 7.7 × 10-7 M) were distribution coefficients of CRP (Kc = 101) and Lp(a) (Kc = 38) were calculated, and the ability to bind large amounts of atherogenic lipoproteins (up to 32 mg of TC per mL of the sorbent gel) was demonstrated. Our sorbent can be recommended for performing complex removal of CRP and atherogenic lipoproteins from the blood plasma in patients with refractory hyperlipidemia and CVD that are accompanied by elevated levels of CRP.

2.
Biochemistry (Mosc) ; 84(1): 33-39, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30927523

RESUMO

It was demonstrated for the first time that immobilized lysozyme can efficiently remove Escherichia coli and Pseudomonas aeruginosa lipopolysaccharides (endotoxins) from solutions. Experimentally confirmed sorption capacity for the developed sorbent was at least 400 ng of endotoxin per ml sorbent. The new sorbent is compatible with the whole human blood and can be potentially used in extracorporeal therapy in the treatment of sepsis.


Assuntos
Enzimas Imobilizadas/uso terapêutico , Lipopolissacarídeos/isolamento & purificação , Muramidase/uso terapêutico , Adsorção , Sangue , Líquidos Corporais , Humanos , Sepse/terapia
3.
Acta Naturae ; 9(2): 82-87, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28740730

RESUMO

The bacteriolytic activity of interleukin-2 and chicken egg lysozyme in the presence of various substances has been studied. Glycine and lysine do not affect the activity of interleukin-2 but increase that of lysozyme, showing a bell-shape concentration dependence peaking at 1.5 mM glycine and 18 mM lysine. Arginine and glutamate activate both interleukin-2 and lysozyme with a concentration dependence of the saturation type. Aromatic amino acids have almost no effect on the activity of both interleukin-2 and lysozyme. Aromatic amines, tryptamine, and tyramine activate interleukin-2 but inhibit lysozyme. Peptide antibiotics affect interleukin and lysozyme similarly and exhibit maximum activity in the micromolar range of antibiotics. Taurine has no effect on the activity of interleukin-2 and lysozyme. Mildronate showed no influence on lysozyme, but it activated interleukin-2 with the activity maximum at 3 mM. EDTA activates both interleukin-2 and lysozyme at concentrations above 0.15 mM.

4.
Acta Naturae ; 8(1): 98-102, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27099789

RESUMO

The bacteriolytic activity of interleukin-2 and hen egg white lysozyme against 34 different species of microorganisms has been studied. It was found that 6 species of microorganisms are lysed in the presence of interleukin-2. All interleukin-2-sensitive microorganisms belong either to the Enterobacteriaceae, Bacillaceae, or the Lactobacillaceae family. It was also found that 12 species of microorganisms are lysed in the presence of lysozyme, and 16 species of microorganisms are lysed in the presence of sodium dodecyl sulfate (SDS). The bacteriolytic activity of interleukin-2 and lysozyme was studied at various pH values.

5.
Bioorg Khim ; 41(3): 292-8, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26502605

RESUMO

The influence ofvarious surfactants (anionic sodium dodecyl sulfate, SDS, cationic dodecyltrimethylarnmonium bromide, DTAB, and zwitterionic cocoamidopropylbetaine, CAPB) on the activity of the chicken egg lysozyme is investigated. Lysis of Gram-positive bacteria by the enzyme was carried out at pH 7.2 and ionic strength of 0.15 M. It was found that at low SDS and DTAB concentrations (less than 1 x 10(-5) M) the bacteriolytic activity increases by 30-140%. At higher concentrations (1 x 10(-5) - 1 x 10(4) M) the activity returns to the level observed in the absence of the surfactants. The elevated activity correlated with the formation of hydrophobic lysozyme-surfactant complexes. Introduction of CAPB at concentrations above 1 x 10(-5) M sig, nificantly diminished the bacteriolytic activity due to CAPB induced aggregation of lysozyme.


Assuntos
Bacteriólise/efeitos dos fármacos , Micrococcus luteus/efeitos dos fármacos , Muramidase/metabolismo , Animais , Betaína/análogos & derivados , Betaína/farmacologia , Galinhas , Muramidase/efeitos dos fármacos , Compostos de Amônio Quaternário/farmacologia , Dodecilsulfato de Sódio/farmacologia , Propriedades de Superfície
6.
Bioorg Khim ; 41(1): 23-30, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26050468

RESUMO

A novel technique for preparation affinity sorbent based on tyramine and tryptamine was proposed. It was shown that tryptamine-Sepharose and tyramine-Sepharose effectively bind IgG, IgA, lipoprotein (a) (Lp(a)) and low density lipoproteins (LDL) from blood plasma. The sorption capacity is 4-9 mg of IgG, 2-4 mg IgA, 3-5:mg of Lp(a) and 5-7 mg of LDL per mL of gel. It was found that new sorbents can bind Lp(a) and IgG as themselves or in a complex of Lp(a) with IgG. The existence of this complex may indicate the presence of anti-Lp(a) autoantibodies in the blood of some patients. The advantages of new sorbents are easiness of its synthesis and stability during use and storage. In practice they can be applied for medical and biotechnological purposes where it is necessary to bind Lp(a), LDL, IgG, IgA.


Assuntos
Cromatografia de Afinidade/métodos , Triptaminas/química , Tiramina/química , Humanos , Imunoglobulina A/química , Imunoglobulina A/isolamento & purificação , Imunoglobulina G/química , Imunoglobulina G/isolamento & purificação , Ligantes , Lipoproteína(a)/química , Lipoproteína(a)/isolamento & purificação , Lipoproteínas LDL/química , Lipoproteínas LDL/isolamento & purificação
7.
Bioorg Khim ; 41(5): 553-8, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26762092

RESUMO

Affinity haemoadsorbents based on WY, WTY, WNY ligands and polysaccharide matrix were developed for the human immunoglobulin G binding. The characteristics of new sorbents such as the binding of total IgG and binding of IgG subclasses were compared. It was found that all new sorbents well extract the IgG from the blood plasma. It was evidenced that WNY-based sorbent is more effective for binding of IgG subclass 3. The determination of physic-chemical characteristics of IgG binding revealed that desorption constants for IgG are 10 ± 3, 28 ± 4 and 13 ± 3 µM for WY, WTY, WNY based sorbents respectively. Maximum sorption capacities for IgG are 43 ± 2, 45 ± 3 and 46 ± 3 mg IgG per ml of sorbent for WY, WTY, WNY based sorbents respectively. Also it was shown that the new sorbents are compatible with blood and are suitable for the medical purposes.


Assuntos
Imunoglobulina G/sangue , Imunoglobulina G/isolamento & purificação , Oligopeptídeos/química , Hemoperfusão , Humanos , Imunoglobulina G/química , Ligantes , Estrutura Molecular , Polissacarídeos/química , Ligação Proteica , Treonina/química , Triptofano/química , Tirosina/química
8.
Bioorg Khim ; 40(2): 166-9, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25895335

RESUMO

DNA aptamer based sorbents are synthesized for binding human IgE. Sorbents effectively removed IgE from human blood plasma. The experimental values of IgE desorption constants were from 11 x 10(-l0) to 1.7 x 10(-10) M depending on the orientation of the aptamer, an insoluble matrix. The sorbents were stable during multiple use. Conditions for sorbent regeneration were picked up. These chromatographic materials can be used for medical and biotechnological applications.


Assuntos
Aptâmeros de Nucleotídeos/química , Cromatografia , Imunoglobulina E/química , Oligonucleotídeos/química , DNA/química , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/isolamento & purificação , Ligação Proteica
9.
Klin Lab Diagn ; (4): 24-7, 2013 Apr.
Artigo em Russo | MEDLINE | ID: mdl-23984550

RESUMO

The article deals with specification of technique of immune-enzyme analysis to detect autoantibodies to beta-adrenergic receptors (beta1-AP) using compound of oligopeptids representing the fragmentations of extracellular sites beta1-AP and chimeric molecule of extracellular section of receptor This technique significantly exceeds the analogues defined in publications by its sensitivity and correlation with diagnosis.


Assuntos
Autoanticorpos/sangue , Cardiomiopatia Dilatada/sangue , Receptores Adrenérgicos beta 1/isolamento & purificação , Autoanticorpos/imunologia , Cardiomiopatia Dilatada/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Peptídeos/síntese química , Peptídeos/imunologia , Receptores Adrenérgicos beta 1/sangue , Receptores Adrenérgicos beta 1/imunologia
10.
Biochemistry (Mosc) ; 77(11): 1312-4, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23240569

RESUMO

In this paper we report the discovery of bacteriolytic activity of an immune system cytokine mediator, interleukin-2. Bacteriolytic activity of interleukin-2 was compared with a well-known bacteriolytic enzyme - chicken egg white lysozyme - by monitoring the lysis of the Gram-negative bacterium Escherichia coli, the Gram-positive coccus Micrococcus luteus, and the Gram-positive spore-forming bacillus Bacillus subtilis. It was found that interleukin-2 has greater specificity to the Gram-negative bacterium E. coli than does lysozyme. In contrast to chicken egg white lysozyme, interleukin-2 does not lyse the Gram-positive coccus M. luteus and the Gram-positive spore-forming bacillus B. subtilis. These results give a new understanding of the biological functions of interleukin-2, a regulatory protein that plays a role in oncological and infectious diseases.


Assuntos
Interleucina-2/metabolismo , Bacillus subtilis/metabolismo , Bacteriólise , Escherichia coli/metabolismo , Humanos , Micrococcus luteus/metabolismo , Muramidase/metabolismo
11.
Bioorg Khim ; 38(3): 315-23, 2012.
Artigo em Russo | MEDLINE | ID: mdl-22997703

RESUMO

In the present work the studies ofbacteriolytic factors from sheep blood plasma have been performed. Three novel enzymes have been identified and characterized. Two of them have a molecular weight 15 +/- 2 kDa and able to lyse the gram-negative Escherichia coli bacteria. The third enzyme has a molecular weight 34 +/- 4 kDa and is able to lyse both gram-negative Escherichia coli and gram-positive Micrococcus luteus bacteria. The bacteriolytic reactions have been studied for all three enzymes; particularly, pH-optima have been identified with respect to the substrate. To identify the enzymes trypsinolysis and consequent MALDI-TOF mass spectrometry studies were performed. The results were compared to data from publicly available databases, such as Swiss-Prot, NCBI, MSDB.


Assuntos
Antibacterianos/química , Bacteriólise , Muramidase/química , Peptídeo Hidrolases/química , Plasma/enzimologia , Ovinos/sangue , Animais , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Parede Celular/química , Cromatografia em Gel , Cromatografia por Troca Iônica , Bases de Dados Factuais , Escherichia coli/efeitos dos fármacos , Micrococcus luteus/efeitos dos fármacos , Peso Molecular , Muramidase/isolamento & purificação , Muramidase/farmacologia , Peptídeo Hidrolases/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
12.
Bioorg Khim ; 38(1): 58-63, 2012.
Artigo em Russo | MEDLINE | ID: mdl-22792706

RESUMO

New chromatographic material based on tryptophil-threonil-tirosine was prepared. This sorbent effectively binds human, sheep, goat and cow immunoglobulins G. New sorbent shows high selectivity for removing immunoglobulins from blood plasma. Effective sorption capacity is 15-25 mg of immunoglobulin G per ml of matrix. Optimal method of covalent attachment ligand to polysaccharide matrix allows achieving high stability of the sorbents in terms of use and storage. This sorbent can be used in medicine and biotechnology.


Assuntos
Cromatografia Líquida/métodos , Imunoglobulina G/isolamento & purificação , Oligopeptídeos/química , Plasma/química , Humanos , Imunoglobulina G/química
13.
Colloids Surf B Biointerfaces ; 88(1): 131-3, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21763113

RESUMO

The key factors of enzymatic lysis of cells are the interaction between the enzyme and the cell - catalytic and non-catalytic adsorption of enzyme on cell surface. Here, the studies of lysis of intact Escherichia coli cells by chicken egg white lysozyme were performed. It was found that the ionic strength has a dual effect onto the system. On the one hand, the desorption constant of the enzyme increases with the increase of the solution ionic strength, which results in a better enzyme performance. On the other hand, due to the higher osmosis, the cell lysis rate decreases with the increasing of ionic strength of the system. It was found that pH 8.6 and 30 mM NaCl are optimal conditions for lysis of E. coli cells by lysozyme.


Assuntos
Bacteriólise/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Muramidase/farmacologia , Concentração de Íons de Hidrogênio
14.
Biochemistry (Mosc) ; 75(9): 1160-4, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21077836

RESUMO

Bacteriophage enzyme preparations exolysin and endolysin were studied. Exolysin (a phage-associated enzyme) was obtained from tail fraction and endolysin from phage-free cytoplasmic fraction of disintegrated Salmonella enteritidis cells. A new method for purification of these enzymes was developed, and their molecular masses were determined. The main catalytic properties of the studied enzymes (pH optimum and specificity to bacterial substrates) were found to be similar. Both enzymes lyse Escherichia coli cells like chicken egg lysozyme, but more efficiently lyse S. enteritidis cells and cannot lyse Micrococcus luteus, a good substrate for chicken egg lysozyme. Similar properties of exolysin and endolysin suggest that these enzymes are structurally similar or even identical.


Assuntos
Endopeptidases/química , Fagos de Salmonella/enzimologia , Proteínas Virais/química , Animais , Biocatálise , Galinhas , Endopeptidases/isolamento & purificação , Endopeptidases/metabolismo , Escherichia coli/metabolismo , Muramidase/metabolismo , Salmonella enteritidis/efeitos dos fármacos , Especificidade por Substrato , Proteínas Virais/isolamento & purificação , Proteínas Virais/metabolismo
15.
Biomed Khim ; 56(6): 739-46, 2010.
Artigo em Russo | MEDLINE | ID: mdl-21395076

RESUMO

Preparation and stability of a few examples of medical sorbents are described. A simple and practical technique has been developed for sorbent preparation with the low weight synthetic ligands such as amino acids, peptides or oligosaccharides. This approach to sorbent preparation enables the development of the new affine columns generation for medicine and biotechnology to be carried out with ease.


Assuntos
Aminoácidos/química , Remoção de Componentes Sanguíneos/métodos , Oligossacarídeos/química , Peptídeos/química , Humanos
16.
Bioorg Khim ; 35(3): 311-22, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19621046

RESUMO

Two fragments corresponding to the 125-133 and 206-218 sequences of a molecule of the beta(1) adrenoreceptor (autoantibodies to this protein are often found in patients with dilated cardiomyopathy) were synthesized by the solid phase method with the use of Fmoc technology. Two new conformational antigens were prepared by directed (regioselective) and undirected (spontaneous) formation of intramolecular and intermolecular disulfide bridges between the corresponding cysteine residues of the synthesized peptides. One of these antigens consisted of a mixture of disulfide isomers, and another antigen was an isomer with a natural arrangement of S-S bridges. Immunosorbents were obtained by immobilization of the synthesizes antigens on the bromocyanogenactivated sepharose and applied to the removal of autoantibodies in a beta(1)-adrenoreceptor from the blood plasma of patients. We demonstrated that the sorbents on the basis of the conformational antigens were more effective in comparison with those containing linear peptide precursors.


Assuntos
Antígenos/química , Dissulfetos/síntese química , Peptídeos/síntese química , Receptores Adrenérgicos beta 1/química , Antígenos/imunologia , Autoanticorpos/sangue , Autoanticorpos/isolamento & purificação , Cardiomiopatia Dilatada/sangue , Cardiomiopatia Dilatada/imunologia , Cromatografia Líquida de Alta Pressão , Dissulfetos/química , Humanos , Técnicas de Imunoadsorção , Peptídeos/química , Peptídeos/imunologia , Estrutura Terciária de Proteína , Receptores Adrenérgicos beta 1/imunologia
17.
Biochem Biophys Res Commun ; 254(3): 685-8, 1999 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-9920801

RESUMO

Malic dehydrogenase (MDH) studied in water and reversed micelles upon pressure application revealed a difference in catalysis. Whereas MDH in water appeared to be not sensitive to the pressure increasing, the catalytic activity of MDH in reversed micelles showed bell-shaped dependencies both on pressure and surfactant hydration degree, w0. The catalytic activity of MDH was found to be maximal under moderate pressure equal to 300-500 bar and at w0 approximately 14 with the difference between lowest and highest levels of the catalytic activity amounted to about 10 times. The work presented demonstrates for the first time the co-operative effect of reversed micelles and pressure application to malic dehydrogenase leading to the enzyme regulation that cannot be realized in aqueous solution.


Assuntos
Malato Desidrogenase/metabolismo , Micelas , Catálise , Ácido Dioctil Sulfossuccínico , Pressão
18.
J Protein Chem ; 17(3): 229-35, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9588946

RESUMO

Monomeric forms of E. coli glyceraldehyde-3-phosphate dehydrogenase have been prepared using two different experimental approaches: (1) covalent immobilization of a tetramer on a solid support via a single subunit with subsequent dissociation of non-covalently bound subunits in the presence of urea, and (2) entrapment of monomeric species into reversed micelles of Aerosol OT in octane. Isolated monomers were shown to be catalytically active, exhibiting KM values close to the parameters characteristic of the tetrameric forms. Like tetramers, isolated monomers did not use NADP7 as a coenzyme.


Assuntos
Escherichia coli/enzimologia , Gliceraldeído-3-Fosfato Desidrogenases/química , Escherichia coli/química , Gliceraldeído-3-Fosfato Desidrogenases/isolamento & purificação , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Micelas , Conformação Proteica
19.
Appl Biochem Biotechnol ; 61(1-2): 47-56, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9100344

RESUMO

Examination of the properties of Escherichia coli and rabbit muscle D-glyceraldehyde-3-phosphate dehydrogenase (GPDHs) modified by 2,3-butanedione has shown that both tetrameric enzymes are stabilized, on selective modification of arginine residues (probably Arg 231), in an asymmetric state with only two active centers capable of performing the dehydrogenase reaction. The functionally incompetent active centers can be alkylated by iodoacetate or iodoacetamide in the case of E. coli enzyme, but are inaccessible for these reagents in the case of rabbit muscle D-GPDH. These results are consistent with the idea that the two homologous enzymes share common principles of the protein design, but differ somewhat in their active centers geometries. Modification of the arginine procedures marked changes in the shape of the charge transfer complex spectrum in the region of 300-370 nm, suggestive of the alterations in the microenvironment of the nicotinamide ring of NAD(+), although the coenzyme binding characteristics remain largely unaltered. On arginine modification, the enzyme becomes insensitive to the effect of AMP on the kinetic parameters of p-nitrophenyl acetate hydrolysis reaction.


Assuntos
Arginina , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Animais , Diacetil/farmacologia , Escherichia coli , Gliceraldeído-3-Fosfato Desidrogenases/química , Iodoacetamida/farmacologia , Músculos/enzimologia , Conformação Proteica , Coelhos , Espectrofotometria Atômica
20.
Biochem Mol Biol Int ; 37(5): 991-1000, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8624507

RESUMO

Chemical modification of E. coli d-glyceraldehyde-3-phosphate dehydrogenase by an arginine-specific reagent, 2,3-butanedione, stabilized the tetrametric enzyme in an asymmetric state, with only two of the four active centers able to catalyze oxidative phosphorylation of D-glyceraldehyde-3-phosphate. The catalytically incompetent active centers retain the capacity of binding NAD+, forming charge transfer complex, and be alkylated by iodoacetamide. Analogous results have been previously obtained with the rabbit muscle D-glyceraldehyde dehydrogenase modified at a single arginine residue per subunit (Kuzminskaya, E.V., Asryants, R.A., and Nagradova, N.K. (1991) Biochim. Biophys. Acta 1075, 123-130), the only differences being inaccessibility of the catalytically incompetent pair of active centers to the alkylating reagent, on one hand, and lower residual activity exhibited by the functioning active centers (3-4%), on the other. In the case of E. coli enzyme, activity loss upon arginine modification never exceeded 80-82%. These results are consistent with the idea that the two enzymes share common principles of the protein design, but differ in the peculiarities of their active centers conformations. An improved method for D-glyceraldehyde-3-phosphate dehydrogenase purification from a wild type E. coli strain is described.


Assuntos
Compostos de Epóxi/química , Escherichia coli/enzimologia , Gliceraldeído-3-Fosfato Desidrogenases/química , Músculos/enzimologia , Animais , Sítios de Ligação , Catálise , Conformação Proteica , Coelhos
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