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N A Andreeva

Publications and source records attributed to N A Andreeva.

At least 19 recordsLinked to original sources
PubMed1995

[Organelle specificity of yeast cell polyphosphatases].

The properties of purified cell envelope polyphosphatase, polyphosphatase activities of vacuoles and cytosol fractions of the Saccharomyces cerevisiae yeast have been compared. The whole body of evidence presently available suggest that each of the compartments under study is equipped with its own polyphosphatase which differs from polyphosphatases of other organelles. It is proposed that the organelle specificity of yeast polyphosphatases may reflect the endosymbiotic origin of eucaryotic cells.

Acid Anhydride Hydrolases↗
PubMed1995

[Immunoenzyme analysis of polyphosphatases from various compartments of yeast cells].

Antibodies against purified polyphosphatase from the Saccharomyces cerevisiae cell envelope inhibited the activity of this enzyme and the polyphosphatase activity of the cytosol, being without any effect on vacuolar and nuclear polyphosphatase activities from the same yeast species cells. Using immunoblotting, it has been shown that it is the 40 kDa polypeptide that binds to these antibodies in preparations of cell envelope and cytosolic polyphosphatase. The molecular mass of these polyphosphatases determined by other methods was almost indentical. The 72 and 40 kDa polypeptides bind to these antibodies in isolated vacuoles, while the 64 and 32 kDa polypeptides--in isolated nuclei.

Acid Anhydride Hydrolases↗
PubMed1994

[Characteristics of polyphosphatase activity of Saccharomyces cerevisiae cytosol].

The cytosol fraction purified from cellular organelles was obtained from S. cerevisiae yeast cells. This cytosolic fraction contained a polyphosphatase activity comprising nearly 65% of such in the protoplast homogenate. The pH optimum of this activity was 6.5-7.5. Bivalent metal cations stimulated the polyphosphatase activity 9-14-fold in the following order: Zn2+ > Co2+ > Mg2+, Mn2+. Fe2+, Cu2+ and Ca2+ ions inhibited this activity at all concentrations used. The cytosolic polyphosphatase was effectively inhibited by molybdate and heparin. Heparin was effective only in the presence of Mg2+, Mn2+ and Co2+ but had no effect in the presence of Zn2+. Heparin inhibited polyphosphatase competitively. The polyphosphatase activity was the same with poly (P)9-poly (P)208. On poly (P)9, poly (P)15 and poly (P)208 the Km(app) values were equal to 19, 11, 1.2 microM, respectively. The molecular mass of cytosolic polyphosphatase determined by gel filtration on Sephacryl S-300 was 50 kDa.

Acid Anhydride Hydrolases↗
PubMed1993

Purification and characterization of highly active and stable polyphosphatase from Saccharomyces cerevisiae cell envelope.

Saccharomyces cerevisiae cell envelope polyphosphatase was isolated in highly active and stable form by extraction from cells with zwittergent TM-314 followed by chromatography of the extract on phosphocellulose and QAE-Sephadex in the presence of 5 mM-MgCl2, 0.5 mM-EDTA and 0.1% Triton X-100. The enzyme possessed a specific activity of 220 U/mg and after 30 days retained 87% of its activity at -20 degrees C. Polyphosphatase molecular mass was determined to be about 40 kDa by gel filtration and polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The enzyme hydrolysed polyphosphates with various chain lengths (n = 3-208), had low activity for GTP and did not split pyrophosphate, ATP and p-nitrophenylphosphate. On polyphosphates with chain lengths n = 3, 9 and 208, Km values were 1.7 x 10(-4), 1.5 x 10(-5) and 8.8 x 10(-7) M respectively. Polyphosphatase was most active and stable at pH 6.0-8.0. The enzyme showed maximal activity at 50 degrees C. The time of half inactivation of polyphosphatase at 40, 45 and 50 degrees C was 45, 10 and 3 min, respectively. In the absence of divalent cations and also with Ca2+ or Cu2+, the enzyme showed practically no activity. The ability of divalent cations to activate polyphosphatase was reduced in the following order: Co2+ > Mg2+ > Mn2+ > Fe2+ > Zn2+. Polyphosphatase was completely inhibited by 1 mM-ammonium molybdate and 50 microM-Zn2+ or Cu2+ (in the presence of Mg2+).

Acid Anhydride Hydrolases↗
PubMed1993

[Characteristics of polyphosphatase activity of vacuoles in Saccharomyces cerevisiae cells].

Vacuoles of the Saccharomyces cerevisiae yeast possess a polyphosphatase activity which differs from other known vacuolar phosphohydrolase activities by pH-optimum, sensitivity towards inhibitors and distribution between the tonoplast and vacuolar sap. The polyphosphatase activity is inhibited by EDTA, molybdate, ortho-vanadate and fluoride. Nearly 77% of this activity is located in the vacuolar sap, while 25%--in the tonoplast fraction. Both the soluble and membrane-bound polyphosphatase activities are maximal at pH 6.8-7.2. Bivalent metal cations stimulate this activity in the following order: Zn2+ > Mg2+ > Co2+ > Mn2+. Other ions (Fe2+, Cu2+, Ca2+) inhibit this activity at all concentrations tested. The polyphosphatase activity of both the vacuolar sap and the tonoplast increases 2.4-and 2-fold, respectively, with an increase in the degree of substrate polymerization--from n = 3 to n = 208.

Cations, Divalent↗
PubMed1991

[Vitamin E decreases the neurocytotoxic action of kainic acid in a cerebellar neuron culture].

Using primary cultures of cerebellar granule cells from 4-6-day old Wistar rats we showed the protective effect of vitamin E against kainate-induced neurotoxicity. The preincubation of 7-8-day old cultures with 5 x 10(-4) M alpha-tocopherol solution significantly (on 10-20%) reduces the number of damaged granule cells. As vitamin E takes part in stabilization of membrane lipids the data presented allows us to suggest that one of the possible mechanisms of neuronal injury includes lipid oxidation of the neuronal membranes which leads to additional influx of Ca2+ and results in neuronal death.

Animals↗
PubMed1990

[The use of a polyethyleneimine substrate for culturing dissociated cells of the central nervous system].

A new method of preparation of polyethylenimin substrate for cultivation of dissociated cells from different parts of the central nervous system is presented. The alcohol solution of polyethylenimin used for this substrate is easily prepared, needs no sterilization and can be stored unlimitedly. The substrate provides a good attachment, growth and differentiation of neurons and glial cells and possesses all the advantages of more expensive polyaminoacid substrates (polylysine, polyornithine). Our substrate is highly adhesive, displays good optical properties and no artefacts after histological and histochemical treatment.

Animals↗
PubMed1989

[Immunocompetent cells in organs of local and systemic immunity in intact and sensitized guinea pigs upon specific intranasal immunotherapy].

The normal levels of some lymphocyte populations and subpopulations in the lungs and lymph nodes draining the respiratory tract have been determined. The influence of systemic delayed hypersensitivity (DH) to staphylococci and the multiple introduction of staphylococcal antigen into intact and sensitized guinea pigs on the distribution of lymphocyte subpopulations in the central, peripheral and respiratory lymphoid organs has been studied. Systemic DH has been found to affect the level of immunocytes in the thymus and peripheral lymphoid organs; the local introduction of the allergen and the intranasal immunotherapy of systemic DH produce both local (the lungs and their lymph nodes) and systemic effect.

Animals↗
PubMed1983

Transmembrane gradient of K+ ions as an energy source in the yeast Saccharomyces carlsbergensis.

In the presence of 100 mM glucose antimycin A inhibits the respiration of the yeast S. carlsbergensis by 94%, but does not affect the K+ efflux, Mn2+ influx or the synthesis of high molecular weight polyphosphate (HPP). Therefore phosphorylation at the respiratory chain level is not involved in HPP synthesis or Mn2+ accumulation. Zn2+ similar to Mn2+ induces K+ efflux and HPP synthesis, while Co2+ and Ni2+ fail to produce these effects. The extracellular K+ (1-5 mM KCl) completely inhibits the HPP synthesis and reduces Mn2+ uptake by 40%. NaCl (60 mM) inhibits the HPP synthesis by 28%. Nigericin, candicidin and FCCP plus valinomycin completely prevent the HPP synthesis. The prolonged accumulation of Zn2+ and Mn2+ is accompanied by HPP conversion into low molecular weight polyphosphate (LPP). The HPP synthesis in response to the K+ efflux may be regarded as a specific regulatory mechanism, which increases the energy efficiency of yeast metabolism.

Antimycin A↗
PubMed1983

Changes of ATP, polyphosphate and K+ contents in Saccharomyces carlsbergensis during uptake of Mn2+ and glucose.

The process of prolonged Mn2+ uptake by the yeast Saccharomyces carlsbergensis in the presence of 100 mM glucose and in the absence of phosphate can be divided into two steps. The first step (0-20 min) of Mn2+ uptake (4.3 mumol/g of wet cells) is characterized by an intense K+ efflux (23.8 mumol/g), synthesis of high molecular weight polyphosphate (HPP) (8.1 mumol/g) and decrease of ATP content (0.06 mumol/g). Simultaneously about 0.6 mumol of glucose is taken up and the level of low molecular weight polyphosphate (LPP) remains practically unchanged. The second step (20-120 min) of Mn2+ uptake (15.6 mumol/g) is characterized by a drop in HPP (16.6 mumol/g) and the synthesis of LPP (19.0 mumol/g). The ATP content decreases by 0.87 mumol/g as compared to the control, while that of K+ increases (5.7 mumol/g). During the first step of Mn2+ uptake the energy of the K+ concentration gradient may be used both for Mn2+ influx (2K+: 1Mn2+) and synthesis of HPP (1P:1.9K+). During the second step the Mn2+ accumulation is apparently driven by HPP conversion into LPP (1:1) and by ATPases serving the Mn2+/H+ exchange.

Adenosine Triphosphate↗
PubMed1979

[Amino acid composition and chemical functional group modification of protease (TI-Ajl) inhibitor from Actinomyces janthinus 118].

The amino acid composition of the protease (TI-Ajl) inhibitor from Actinomyces janthinus 118 has been determined. It was shown that the TI-Ajl, S-SI and plasminostreptin inhibitors of trypsin and subtilisin have a number of common features: number of double bonds, tryptophane and tyrosine residues, prevalence of the acidic amino acids over the basic ones, ets. The effect of chemical modification of amino groups, arginine, tyrosine and methionine residues on the inhibitory activity of TI-Ajl was studied. The data obtained are indicative of the presence of two active centers of the inhibitor. The antitrypsin center contains a lysine residue.

Actinomyces↗
PubMed1979

[Stability and specificity of extracellular protein inhibitor for trypsin from Actinomyces janthinus 118].

Some properties of protein inhibitor for trypsin (TI) from Act. janthinus 118 were studied. It was shown that TI has an antitrypsin activity within a wide pH range with a maximum at about 9,5. At 4 degrees and 20 degrees C TI is stable for 24 hours within the pH range of 6,0--11,0. At 100 degrees C TI is more stable in the slightly acid region of pH than at neutral or alkaline conditions. Trypsin and chymotrypsin inactivate the inhibitor for 8 hours. TI inhibits trypsin, fibrinolysin, subtilisin, pronase and terrilytin, but have no effect on chymotrypsin, thrombin, papain and pepsin. The dissociation constants for the trypsin-inhibitor complex were found to be 1,7.10-8 M, 4,1.10-9 M and 2,4.10-10 M, with casein, p-nitroanilide benzoylarginine and tosylarginine methyl ester used as substrates, respectively. The corresponding dissociation rate constants for the subtilisin-inhibitor complex were equal to 1.10-9 M and 4.10-10 M with casein and carbobenzoxy-L-alanyl-L-alanyl-L-leucin p-nitroanilide used as substrates, respectively.

Actinomyces↗