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Applied Biochemistry and Microbiology (v.40, #2)
Biochemical Aspects of Plant Interactions with Phytoparasitic Nematodes: A Review by S. V. Zinov'eva; N. I. Vasyukova; O. L. Ozeretskovskaya (pp. 111-119).
The review summarizes reports on molecular aspects of interactions of phytoparasitic nematodes with plant hosts. Data on nematode secretions affecting plants (elicitors, toxins, products of parasitism genes, etc.) are analyzed and information flow pathways comprising all elements of the plant–parasite interaction (from elicitors to defense responses of plant cells) are described. Emphasis is placed on the mechanisms whereby plants are protected from nematode invasion (hypersensitivity reactions, apoptosis, phytoalexins, proteinase inhibitors, PR proteins, etc.). Consideration is given to genetic aspects of plant–parasite relationships. Promising practical approaches to defending plants from phytoparasitic nematodes developed based on the results of studies of molecular mechanisms of plant–parasite interactions are presented in the conclusion.
Inactivation of Glucose-6-Phosphate Dehydrogenase in Solution by Low- and High-Frequency Ultrasound by Zh. V. Rachinskaya; E. I. Karasyova; D. I. Metelitza (pp. 120-128).
We compared the kinetics of glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) inactivation in 0.1 M phosphate buffer (pH 7.4) at 36–50°С under conditions of exposure to low-frequency (LF, 27 kHz, 60 W/cm2) or high-frequency (HF, 880 kHz, 1.0 W/cm2) ultrasound (USD). The inactivation of G6PDH was characterized by effective first-order rate constants: k in, total inactivation; k in *, thermal inactivation; and k in(usd), ultrasonic inactivation. Dilution of the enzyme solution from 20 to 3 nM was accompanied by a significant increase in the values of the three rate constants. The following inequality was valid in all cases: k in > k in *. The rate constants increased with temperature. The Arrhenius plots of the temperature dependences of k in and k in(usd) had an break point at 44°C. The activation energy (Е act) of the total inactivation of G6PDH was higher than Е act for the process of ultrasonic inactivation of this enzyme. The two values were found to depend on USD frequency: Е act was higher in the case of inactivation with low-frequency ultrasound (LF-USD) than high-frequency ultrasound (HF-USD). The rate of the ultrasonic inactivation of this enzyme substantially decreased in the presence of low concentrations of HO. radical scavengers (dimethylformamide, ethanol, and mannitol). This fact supports the conclusion that free radicals are involved in the mechanism of G6PDH inactivation in solutions exposed to LF-USD and HF-USD. Ethanol was an effective protector of G6PDH inactivation in solutions exposed to USD.
Transglycosylation of Stevioside by Cyclodextrin Glucanotransferases of Various Groups of Microorganisms by V. A. Abelyan; A. M. Balayan; V. T. Ghochikyan; A. A. Markosyan (pp. 129-134).
Cyclodextrin glucanotransferases (CGTases, EC 2.4.1.19) produced by mesophilic, thermophilic, alkaliphilic, and halophilic bacilli were used for transglycosylating stevioside (in order to remove bitterness and aftertaste), with cyclodextrins (CDs) being used as donors. It was shown that CGTases produced by extremophilic microorganisms are effective biocatalysts. Optimum temperature and pH of these enzymes were 45°C and pH 6.5–7.5, respectively. The optimum stevioside-to-CD ratio and total concentration of dry matter for the synthesis of the best-tasting product were 1 : 1 (w/w) and 11.6%, respectively.
Ecdysone 20-Monooxygenase Activity of Cytochrome P450 in Ajuga reptans L. Plants and Cell Culture by L. I. Alekseeva (pp. 135-139).
The concentration of cytochrome P450 and ecdysone 20-monooxygenase activity in plants and callus cell culture of carpet bugleweed Ajuga reptans L. were determined. The maximal ecdysone 20-monooxygenase activity of cytochrome P450 was found in vegetative rosettes of intact plants. During the stage of flowering, the ecdysone 20-monooxygenase activity of cytochrome P450 in plant leaves was higher than in other organs. It was demonstrated that the content of ecdysteroids in callus cell culture is higher than in the intact plant, with concurrent retention of a high ecdysone-20-monooxygenase activity.
Phenylpyrazolones, Novel Oxidoreductase Redox Mediators for Degradation of Xenobiotics by S. V. Shleev; Ir Gvon Khan; O. V. Morozova; Yu. M. Mazhugo; A. S. Khalunina; A. I. Yaropolov (pp. 140-145).
An approach was developed for screening organic compounds as putative redox mediators of oxidoreductases, including laccases and peroxidases, applicable for xenobiotic degradation. The study was carried out with a homogeneous laccase preparation from the basidiomycete Trametes hirsuta and horseradish peroxidase. Compounds belonging to 1-phenyl-3-methylpyrazolones were selected. Spectroscopic and electrochemical investigation of two of the compounds, sodium 1-phenyl-2,3-dimethyl-4-aminopyrazolone 5n(4)-methanesulfonate (PPNa) and 1-(3′-sulfophenyl)-3-methylpyrazolone (SPP), was performed. Electrochemical oxidation of both PPNa and SPP gave rise to high-potential intermediates capable of oxidizing veratryl alcohol, a lignin-modeling compound. Kinetic parameters of these compounds were determined in enzymatic reactions in the presence of laccase. It was shown that enzymatic oxidation of SPP by laccase produced high-potential intermediates capable of oxidizing veratryl alcohol to veratric acid. Veratryl alcohol was not oxidized during enzymatic oxidation of SPP by peroxidase. This points to a difference between the mechanisms of enzymatic oxidation of PPNa and SPP by laccase and peroxidase.
Properties of and Prospects for Practical Use of Extracellular L-Glutamate Oxidase of Streptomycessp. Z-11-6 by M. V. Sukhacheva; N. I. Zhuravleva (pp. 146-150).
The properties of extracellular L-glutamate oxidase isolated and purified from Streptomycessp. Z-11-6 (specific activity, 50.8 U/mg protein; yield, 40%) were studied. A photometric method of determination of activities of alanine and aspartate aminotransferases based on the use of L-glutamate oxidase and peroxidase has been developed. This method is sufficiently sensitive to be used for determining aminotransferase activities in biological fluids. The presence of other amino acids does not interfere with the analysis and has no effect on the results of determination.
Quartz Sand as an Adsorbent for Purification of Extracellular Glucose Oxidase from Penicillium funiculosum 46.1 by A. N. Eryomin; A. P. Drozhdenyuk; G. K. Zhavnerko; T. V. Semashko; R. V. Mikhailova (pp. 151-157).
A procedure for purification of extracellular glucose oxidase (GO, EC 1.1.3.4) from a filtrate of culture liquid (CLF) of the fungus Penicillium funiculosum 46.1 has been developed using alluvial quartz sand as an adsorbent. Modifying the sand by changing the charge and polarity did not lead to a significant increase in its adsorption capacity towards GO. The effectiveness of sand and aluminum oxide used as adsorbents for GO isolation from CLF has been compared. Glucose oxidase isolated from CLF by adsorption on sand exhibited a greater catalytic activity than enzyme preparations obtained by column chromatography on CLF. Glucose oxidase from P. funiculosum 46.1 was adsorbed on sand more effectively than on aluminum oxide. It is concluded that sand may be used for fractionation of partially purified GO.
Immobilization of Champagne Yeasts by Inclusion into Cryogels of Polyvinyl Alcohol: Means of Preventing Cell Release from the Carrier Matrix by N. N. Martynenko; I. M. Gracheva; N. G. Sarishvili; A. L. Zubov; G. I. El'-Registan; V. I. Lozinsky (pp. 158-164).
Wine champagnizing, a process involving the use of champagne yeasts immobilized by inclusion into cryogels of polyvinyl alcohol, has been studied. Treatment of yeast cells with the autoregulatory factor d 1 was proposed as a means of preventing the cell release from the carrier matrix. Such a treatment inhibited growth and proliferation processes in yeast cells, without affecting the activity of fermentation; the resulting champagne had the same organoleptic and chemical characteristics as its counterparts obtained using conventional techniques.
Exoproteinases of the Oomycete Phytophthora infestans by E. L. Gvozdeva; E. V. Ievleva; N. G. Gerasimova; O. L. Ozeretskovskaya; T. A. Valueva (pp. 165-169).
When grown in a medium containing heat-stable potato tuber proteins, the oomycete Phytophthora infestans (Mont.) de Bary produces a set of exoproteinases active at neutral and mildly basic pH values. These extracellular proteinases have been shown (by SDS-PAGE in the presence of gelatin) to include at least six components differing in molecular weight. Inhibitory analysis and studies of the effects of the enzymes on various synthetic substrates show that the culture liquid of P. infestans contains mainly serine proteinases (specific for trypsin and subtilisin) and metalloproteinases. Their activity is suppressed by proteinase-inhibiting proteins from potato tubers. It is suggested that exoproteinases of P. infestans may be the metabolic target for natural proteinase inhibitors from potato.
Dynamics of Activity of the Key Enzymes of Polyhydroxyalkanoate Metabolism in Ralstonia eutropha B5786 by T. G. Volova; G. S. Kalacheva; O. V. Gorbunova; N. O. Zhila (pp. 170-177).
The dynamics of accumulation of polyhydroxybutyrate (PHB) and the activities of key enzymes of PHB metabolism (β-ketothiolase, acetoacetyl-CoA reductase, PHB synthase, D-hydroxybutyrate dehydrogenase, and PHB depolymerase) in the hydrogen bacterium Ralstonia eutropha B5786 were studied under various conditions of carbon nutrition and substrate availability. The highest activities of β-ketothiolase, acetoacetyl-CoA reductase, and PHB synthase were recorded during acceleration of PHB synthesis. The activities of enzymes catalyzing PHB depolymerization (PHB depolymerase and D-hydroxybutyrate dehydrogenase) were low, being expressed only upon stimulated endogenous PHB degradation. The change of carbon source (CO2 or fructose) did not affect the time course of the enzyme activity significantly.
Antimicrobial Activity of Lactic Acid Bacteria from Sour Milk Products Narine, Karine, and Matsun by A. O. Martirosyan; Sh. L. Mndzhoyan; L. M. Charyan; L. G. Akopyan; M. N. Nikishchenko (pp. 178-180).
We studied antimicrobial properties of lactic acid bacteria from sour milk products Narine, Karine, and Matsun. The whey of the sour milk products included two major fractions, of sugars and L-lactic acid and its sodium and calcium salts. Antimicrobial activity of Narine, Karine, and Matsun was related to the presence of L-lactic acid and its sodium and calcium salts.
Effect of Photosynthetic Bacteria and Compost on Degradation of Petroleum Products in Soil by Kh. Ten; O. A. Kirienko; E. L. Imranova (pp. 181-185).
Addition of diesel fuel and waste engine oil to soil was found to stimulate hydrocarbon-oxidizing microorganisms. Corynebacteria constitute a large group of hydrocarbon-oxidizing microorganisms. Addition of a liquid culture of photosynthetic bacteria to soil facilitates degradation of petroleum products and also stimulates growth of hydrocarbon-oxidizing microorganisms. Combined addition of photosynthetic bacteria and compost to soil polluted with petroleum products produces a greater increase in the number of hydrocarbon-oxidizing bacteria and substantially augments the rate of pollutant degradation.
Germination of Basidiospores of Agaricus bisporus by E. P. Feofilova; V. M. Tereshina; L. V. Garibova; L. A. Zav'yalova; A. S. Memorskaya; N. S. Maryshova (pp. 186-191).
The type of dormancy and conditions necessary for germination of Agaricus bisporus basidiospores were studied. Basidiospores failed to germinate on starvation agar and required the presence of carbon and nitrogen sources (asparagine and/or glucose) in the medium. Upon 3-week storage, basidiospores germinated after 4–5 days. Heat shock (20 min at 45°C) and decreased temperature facilitated activation of germination. Heterocyclic compounds stimulating germination of endogenously dormant spores, such as furfural, failed to activate germination. The data obtained suggested an endogenous dormancy of A. bisporus basidiospores differing from zygospores of Mucorales. Basidiospores contained 17–19% lipids with a composition of fatty acids differing from those of the pileus and stipe of the fruiting body. The soluble carbohydrates of the cytosol amounted to 12% dry spore weight and consisted of mannitol (74%) and trehalose (26%). Unlike basidiospores stored at 2°C, basidiospores stored for 5 months at 20°C lost their ability to germinate, which correlated with a decrease in the content of trehalose.
Development of Magnetic Biosorbents and Their Application in Immunoassays of Microbial Antigens by S. M. Kal'noi; V. I. Goncharov; N. F. Vasilenko (pp. 192-198).
The feasibility of rendering erythrocytes magnetic and thereby creating magnetic biosorbents through a room temperature exposure to 25–37% iron (II) sulfate solution for 48 ± 2 h followed by exposure to 15–25% aqueous ammonia solution for 48 ± 2 h (with drying after each procedure) was demonstrated. The feasibility of immobilizing ligands on magnetic erythrocytes and obtaining biological magnetic immunosorbents (BMISs) for further use in EIAs for plague and tularemia antigens was demonstrated. The sensitivity of EIAs involving BMISs amounted to 10 ng/ml and 100 microbial cells per 1 ml. The relative error did not exceed 8%.
Competitive Immunochemical Determination of Antigens Using Conjugates Containing Co(II) and Ni(II) by Yu. I. Dykhal; E. P. Medyantseva; N. R. Murtazina; N. V. Kalacheva; G. K. Budnikov (pp. 199-205).
A new variant of competitive heterogeneous immunoassay for certain proteinaceous antigens has been developed. The assay is based on the use of the target protein conjugated with Co(II) or Ni(II) ions and immobilized antibodies. The effect of catalytic hydrogen release allows quantitation of the metal ion labels by voltammetry at the final step of the assay. The conjugates have been characterized by spectrophotometry, voltammetry, atomic adsorption spectrometry, and nuclear magnetic relaxation. Based on the use of the conjugate RNase–diethylenetriaminepentaacetic acid–Co(II) (10 : 4 : 4), a competitive immunoassay for RNase has been developed, detecting the target protein in the range 2 × 10–2–2 × 10–4 mg/ml.
Specific Features of Cultivation of Iris ensata Thunb. Callus Tissue by E. V. Boltenkov; V. G. Rybin; E. V. Zarembo (pp. 206-212).
A continuous callus culture was obtained from zygotic embryos of Japanese iris (Iris ensata Thunb.) on Murashige–Skoog medium supplemented with 2 mg/l α-naphthylacetic acid and 0.5 mg/l 6-benzylaminopurine (BAP). It was found that successful callusogenesis required isolated embryos at the wax stage of endosperm development. The optimal combination of phytohormones for the growth of callus tissue was 1 mg/l 2,4-dichlorophenoxyacetic acid and 0.5 mg/l BAP. The pigment composition of I. ensata callus tissue was studied. It was demonstrated that subcultivated callus tissue contained red pigments of flavonoid nature. Under stress cultivation conditions, yellow pigments were formed and the content of red pigments increased.
Influence of Systemic Signal Molecules on the Rate of Spread of the Immunizing Effect of Elicitors over Potato Tissues by O. L. Ozeretskovskaya; V. P. Varlamov; N. I. Vasyukova; G. I. Chalenko; N. G. Gerasimova; Ya. S. Panina (pp. 213-216).
Mobile systemic signal molecules (salicylic and jasmonic acids) enhance and accelerate the spread of the systemic immunizing effect of elicitors (arachidonic acid and chitosan) over potato tuber tissues (Solanum tuberosum L.).