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Applied Biochemistry and Microbiology (v.37, #6)
Plant Proteinase Inhibitors as Multifunctional Proteins (Review) by V. V. Mosolov; L. I. Grigor'eva; T. A. Valueva (pp. 545-551).
Data in the literature on plant proteinase inhibitors as multifunctional proteins are reviewed. In addition to the direct inhibitory effect on enzymes, these proteins may function in other processes, particularly under biotic and environmentally stressful conditions. A special section discusses the relationships of plant proteinase inhibitors and storage proteins.
Formation of Wine Aroma: Tones and Imperfections Caused by Minor Components (Review) by A. F. Pisarnitskii (pp. 552-560).
Mechanisms of the formation of primary and secondary wine aromas and processes associated with wine maturation and aging are reviewed. Compounds determining brand- or technology-specific aroma tones (floral, fruit, honey, black-currant, nightshade, yeast, oak-cask, thermal-treatment, etc.) are identified. Chemical background of unacceptable, foul tones (oxidized, murine, acetate, hydrogen-sulfide, saprogenic, cabbage, hospital, mold, vulpine, etc.) is presented.
Coproporphyrins, Uroporphyrins, and Their Metal Comlexes: Biosynthesis and Application to Immune Analysis and Diagnostic Methods by V. Ya. Bykhovsky; N. I. Zaitseva; A. F. Mironov; N. S. Osin; E. V. Pecherskikh; V. D. Rumyantseva; G. M. Sukhin (pp. 561-568).
Methods of synthesis of coproporphyrin and uroporphyrin by using bacteria of the genus Arthrobacterare proposed. Metal complexes of coproporphyrin and uroporphyrin with Pt, Pd, and Zn were synthesized. Their structures were identified by spectrophotometry, IR spectrometry, 1H-NMR, mass spectrometry, and HPLC. Data showing the possibility of using coproporphyrin III–metal complexes as luminophores for fluorescence detection of tumors was gathered. The current and prospective uses of metal complexes of water-soluble natural porphyrins in advanced immunofluorescence assays are discussed.
Characterization of Glutaminase from Triticale by L. I. Sidel'nikova; Z. G. Evstigneeva; N. A. Solov'eva; V. R. Shatilov (pp. 569-573).
The glutaminase (EC 3.5.1.2) isolated from seedlings of triticale (Triticalesp.) had a pH optimum of about 8, was inhibited with excess substrate (glutamine), and reaction products (glutamate and NH+ 4). A monocharged anion (Cl–) and a multicharged anion (phosphate) were shown to activate the glutaminase. Some features of the glutaminase from triticale were similar to those of animal glutaminase activated by phosphate and were different from features of the enzyme from Escherichia coli.
Purification and Characterization of Alkaline Proteinase from AlkalophilicBacillussp. by A. Muderriszade; N. Y. Ensari; S. Aguloglu; B. Otludil (pp. 574-577).
Alkaline proteinase was purified from Bacillussp. isolated from soil. The pH optimum was 11.5 at 37°C. Calcium divalent cation was effective in stabilizing the enzyme, especially at higher temperatures. The proteolytic activity was inhibited by the specific serine proteinase inhibitor PMSF (phenylmethylsulfonyl fluoride), and ions of Mg, Mn, Pb, Li, Zn, Ag, and Hg. The enzyme was stable in the presence of detergents, such as Triton-X100, Tween-80, SDS (sodium dodecyl sulfate), and EDTA (ethylenediaminetetraacetic acid), at pH 11.5 and 37°C for 30 min. The optimum pH was 11.5 at 37°C, and the optimum temperature was 62°C at pH 11.5.
Thermal Stability of Glucose Oxidase from Penicillium adametzii by A. N. Eremin; D. I. Metelitsa; Zh. F. Shishko; R. V. Mikhailova; M. I. Yasenko; A. G. Lobanok (pp. 578-586).
The thermal stability of glucose oxidase was studied at temperatures between 50 and 70°C by kinetic and spectroscopic (circular dichroism) methods. The stability of glucose oxidase was shown to depend on the medium pH, protein concentration, and the presence of protectors in the solution. At low protein concentrations (<15 μg/ml) and pH > 5.5, the rate constants k in, s–1, for thermal inactivation of glucose oxidase were high. Circular dichroic spectra suggested an essential role of β structures in stabilizing the protein globule. At a concentration of 15 μg protein/ml, the activation energy E Aof thermal inactivation of glucose oxidase in aqueous solution was estimated at 79.1 kcal/mol. Other thermodynamic activation parameters estimated at 60°C had the following values: ΔH= 78.4 kcal/mol, ΔG= 25.5 kcal/mol, and ΔS= 161.9 entropy units. The thermal inactivation of glucose oxidase was inhibited by KCl, polyethylene glycols, and polyols. Among polyols, the best was sorbitol, which stabilized glucose oxidase without affecting its activity. Ethanol, phenol, and citrate exerted destabilizing effects.
Isolation and Properties of Cellobiase from Penicillium verruculosum by I. N. Zorov; A. V. Gusakov; V. A. Baraznenok; A. O. Bekkarevich; O. N. Okunev; A. P. Sinitsyn; E. G. Kondrat'eva (pp. 587-593).
Cellobiase (β-D-glucosidase) with a molecular weight of 100 kDa and pI 5.2 was isolated from the cellulolytic system of Penicillium verruculosum. Kinetic parameters of enzymatic hydrolysis of cellobiose, gentiobiose, sophorose, and synthetic substrates, i. e. methylumbelliferyl and p-nitrophenyl sugar derivatives were determined. Glucose and D-glucose-δ-lactone competitively inhibited cellobiase (K i0.19 mM and 17 μM, respectively). Glucosyl transfer reactions were studied with cellobiose as a single substrate and in the mixture of cellobiose and methylumbelliferyl cellobioside. The product composition was determined in these systems. The ratio of hydrolysis and transfer reaction rates for cellobiose conversion was calculated.
Biosynthesis of Pectinase by Fungi of the Genera Bjerkanderaand Coriolusduring Solid-Phase Fermentation by Kh. G. Ganbarov; N. A. Kulieva; P. Z. Muradov (pp. 593-595).
Production of an extracellular pectinase by wood-rot fungi of the genus Bjerkanderaand Corioluswas studied. The active producersB. adusta40 and C. versicolor24 were selected. The dynamics of production of pectinase and effects of temperature, initial pH, humidity of the medium, and addition of nitrogen sources on the biosynthesis of pectinase were studied.
The Insecticidal Activity of Bacillus thuringiensisCells by N. A. Khuzhamshukurov; T. Yu. Yusupov; I. M. Khalilov; A. G. Guzalova; M. M. Muradov; K. D. Davranov (pp. 596-598).
The effects of sixteen different nutrient media on the entomopathogenic activity of three Bacillus thuringiensisstrains was studied. The medium composition based on potato, yeast extract, and molasses was optimized. B. thuringiensisno. 1 grown on the media nos. 7 and 9 displayed the highest entomopathogenic activity (94.3 and 90.6%, respectively).
Search for Methanotrophic Producers of Exopolysaccharides by Yu. R. Malashenko; T. P. Pirog; V. A. Romanovskaya; I. G. Sokolov; T. A. Grinberg (pp. 599-602).
Bacteria that produce exopolysaccharides (EPS) and use methane as the only source of carbon were selected by studying a collection of methanotroph strains: Methylococcus capsulatusE 494, 874, and 3009; M. thermophilus111p, 112p, and 119p; Methylobacter ucrainicus159 and 161; M. luteus57v and 12b; Methylobactersp. 100; Methylomonas rubra15 sh and SK-32; Methylosinus trichosporiumOV3b, OV5b, and 4e; M. sporium5,12, A20d, and 90v; and Methylocystis parvusOVVP. Mesophilic methanotroph strains with the ribulose monophosphate way of C1-compound assimilation synthesized EPS more actively than bacteria operating the serine cycle. The dynamics of EPS synthesis by methanotrophs during chemostat cultivation was studied.
Activity of Carbon Metabolism Enzymes in Wheat Plants Treated with Kartolin-4 and Exposed to Water Stress by I. I. Chernyad'ev; O. F. Monakhova (pp. 603-609).
Enzymatic activities of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) (EC 4.1.1.39), phospho(enol)pyruvate carboxylase (EC 4.1.1.31), NAD malate dehydrogenase (EC 1.1.1.37), and NADP glyceraldehyde phosphate dehydrogenase complex including phosphoglycerate kinase (EC 2.7.2.3) and glyceraldehyde phosphate dehydrogenase (EC 1.2.1.13) were comparatively assayed in wheat seedlings of the cultivar Lyutestsens 758 grown under normal conditions, water deficiency conditions, and subsequent rehydration. Water stress was found to decrease the activity of all enzymes tested, the effect being most pronounced in the case of Rubisco. The content of Rubisco in wheat plants exposed to water deficiency was reduced less significantly than the activity of the enzyme. Pretreatment of plant seeds with kartolin-4 (o-isopropyl-N-2-hydroxyethyl carbamate), a preparation with cytokinin activity, reduced the dehydration-induced inhibition of enzymatic activity. Upon a subsequent rehydration, kartolin-4 facilitated rapid recovery of the photosynthetic activity, the process being based on the kartolin-induced stimulation of reparation reactions. Under conditions of water stress, a partial decrease in the activity of carbon metabolism enzymes in vitrowas accompanied by complete inhibition of photosynthesis in vivo, perhaps, as a result of an abrupt increase in the stomatal resistance.
Inhibition of 3,3",5,5"-Tetramethylbenzidine and o-Phenylenediamine Peroxidation with 1-Amino-2-Naphtol-4-Sulfonic Acid and Its Polydisulfide by E. I. Karaseva; Yu. P. Losev; D. I. Metelitsa (pp. 610-617).
The kinetics of coupled peroxidation of 3,3",5,5"-tetramethylbenzidine (TMB) and 1-amino-2-naphtol-4-sulfonic acid (ANSA) or its polydisulfide (poly(ADSNSA)) was studied in a 0.01 M phosphate buffer (pH 6.4) at 20°C. Both ANSA and poly(ADSNSA) strongly inhibited the TMB oxidation resulting in a marked delay in the product formation. Stoichiometric inhibition coefficients f, i. e., the average numbers of free-radical particles terminated by one inhibitor molecule, were estimated. The free-radical trapping effect of poly(ADSNSA) was 7.5 times greater than that of ANSA. Kinetics of coupled o-phenylenediamine (PhDA) and ANSA or poly(ADSNSA) oxidation was studied in phosphate–citrate buffers at pH 3 to 7. No lag periods in oxidation product accumulation were observed under any of the reaction conditions. A weak activation of PhDA conversion depending on pH and PhDA/ANSA ratios was observed at low ANSA concentrations, whereas increased ANSA or poly(ADSNSA) concentrations were inhibitory. The degree of PhDA-inhibition was maximal in acid media, reached minimum at pH 5 to 6, and than again increased at pH above 6. A tentative mechanism of coupled aromatic amine–phenol bi-substrate system peroxidation is discussed.
Ethylene-Induced Activation of Xylanase in Adventitious Roots of Maize as a Response to the Stress Effect of Root Submersion by T. V. Bragina; L. I. Martinovich; N. A. Rodionova; A. M. Bezborodov; G. M. Grineva (pp. 618-621).
Submersion of roots of ten-day-old maize (Zea maysL.) seedlings was accompanied by a decrease in pO2and an increase in pCO2of the medium adjacent to the roots. These changes stimulated ethylene evolution in intact plants. Enhanced biosynthesis of ethylene was accompanied by xylanase activation in adventitious roots. As a result, an enhanced formation of aerenchyma was observed in the cortex of adventitious roots. Therefore, these processes resulted in the development of a ventilation system by which O2can reach the root system exposed to hypoxia. The volume of aerenchyma was assessed by the volume of gas cavities (porosity). In contrast to the main root, the growth of adventitious roots was not inhibited under these conditions. Enlargement of the stem base and increase in the number of aerenchymatous adventitious roots facilitated the oxygen supply to the submerged organs of the plants.
Influence of the Duration and Conditions of Storage on the Composition of the Essential Oil from Coriander Seeds by T. A. Misharina (pp. 622-628).
The composition of volatile components of the essential oil extracted from seeds of coriander (Coriandrum sativumL.) grown in different years in either Russia or Georgia was studied by capillary gas chromatography. Climatic conditions had a weaker effect on the essential oil composition than the region of growth. After one-year storage in the dark, minor changes were observed in the oil composition, and its organoleptic properties were virtually unchanged. However, the essential oil underwent significant chemical transformation of monoterpenes when stored in the light.
Defatting and Clarification of Protein Hydrolysates by Using Chitosan Solutions by V. Yu. Novikov; V. A. Mukhin (pp. 629-634).
The possibility of the use of small amounts of chitosan for defatting and clarification of protein solutions prepared by enzymatic hydrolysis was tested. The following treatment conditions were shown to be optimal: a chitosan concentration range, from 1.0 to 1.5 gram per kilogram raw weight; pH of the precipitation medium from 8.0 to 8.5; and duration of the incubation of the protein hydrolysate solution with chitosan, less than 1 h. The hydrolysate defatting grade was found to depend on the degree of chitosan deacetylation. A possible mechanism of the chitosan-induced effects was suggested. The use of chitosan allows the mass fraction of enzyme protein hydrolysates to be reduced fourfold to fivefold.
A Kinetic Method for Tungsten Determination in Tungsten-Containing Enzymes by A. N. Nosikov; E. V. Chichikalo; N. P. L'vov (pp. 635-637).
A highly sensitive method for tungsten detection in proteins based on the ability of this metal to catalyze the oxidation of rubeanic acid with hydrogen peroxide is described. The method allows the determination of tungsten in protein samples in the concentration range of 0.05 to 0.4 μg/ml. Molybdenum, at a concentration lower than half the concentration of tungsten, as well as iron, selenium, and pterin at concentrations 2.5 times higher than that of tungsten, had no effect on tungsten determination by this method.
EPR Spectroscopic Study of the Interaction of E. coliCells with Ascorbic Acid and Sodium Nitrite by T. T. Zhumabaeva; L. M. Baider; L. A. Volodina; Z. V. Kuropteva (pp. 638-642).
Ascorbic acid, an effective modulator and regulator of cell metabolism, was shown to induce the production of nitric oxide inE. colicells. This process was detected by EPR spectroscopy as the generation of a spectral signal typical of nitrosyl–iron–sulfur centers (Fe–S–NO) under anaerobic conditions. Incubation of E. colicells in the presence of ascorbic acid under aerobic conditions was shown to be accompanied by sodium nitrite formation. It is suggested that ascorbic acid is capable of supporting the system of energy supply to cells in hypoxia caused by reduced oxygen content or treatment with sodium nitrite.
The Fourth International Seminar-Presentation “Biotechnologies-2000”
by T.A. Reshetilova (pp. 643-648).