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Applied Biochemistry and Microbiology (v.39, #5)
Physiological and Biochemical Characteristics of Immobilized Champagne Yeasts and Their Participation in Champagnizing Processes: A Review by N. N. Martynenko; I. M. Gracheva (pp. 439-445).
Methods for immobilizing champagne yeasts, physiological and biochemical characteristics of the immobilized cells, and problems of their utilization in the production of quality champagne wines are reviewed. Studies aimed at the development of efficient biocatalysts for champagnizing wines using bottle fermentation (methode champenoise) and tank processing (bulk, or Charmat process) based on the use of immobilized yeast cells are described. Data on the industrial use of such biocatalysts in countries manufacturing champagne wines are presented. Problems and prospects of further research in this field are discussed.
Studies of Peroxidase Refolding in the Presence of Specific Antibodies by E. Yu. Bezsudnova; A. V. Zherdev; D. N. Ermolenko; I. V. Yakovleva; V. V. Sviridov; V. O. Popov; B. B. Dzantiev (pp. 446-453).
A panel of eight monoclonal antibodies raised against horseradish root peroxidase was assembled and characterized. Affinity constants were determined for all antibodies, and their specificity for various structural forms of the enzyme (native peroxidase, apoperoxidase, and denatured peroxidase) were assessed by competitive enzyme immunoassay. The effects of the antibodies on the process of refolding of peroxidase after its denaturing with 6.5 M guanidine chloride were studied spectrophotometrically, by the restoration of the enzymatic activity in the reaction of 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonate) oxidation. The yield of the active enzyme in the course of the refolding was increased by 1.5–1.7 times in the presence of antibody H1. Effects of the antibodies constituting the panel on the activity of native peroxidase and the stability of its dilute solutions were analyzed.
Effect of Toxic Industrial Pollutants on the Activity and Isoforms of Acid DNase in the Freshwater Snail Viviparus viviparusL. by A. P. Popov; A. S. Konichev; I. L. Tsvetkov (pp. 454-458).
The effect of various toxic compounds (phenol, gasoline, detergents, halogenated benzenes, and copper salts) on the activity and multiple forms of acid DNase was studied in the liver of the widely occurring freshwater snail species Viviparus viviparus L. Characteristic variations in the specific activity and isoform pattern of the enzyme were revealed depending on pollutant concentration and exposure time. It was shown that the pattern of DNase isoforms in V. viviparus could be an index of water pollution.
Effect of Endogenous Enzymes on the Composition of Oligonucleotides Isolated from Gonads of Hydrobionts by Yu. M. Pozdnyakova; T. N. Pivnenko; Yu. I. Kas'yanenko (pp. 459-463).
Preparations of low-molecular-weight DNA were obtained from gonads of various hydrobiont species by an alcohol precipitation technique. An enzymatic hydrolysis–based method for producing soluble low-molecular-weight DNA was developed. All the nucleic acid components of the preparations obtained were separated by electrophoresis, and their molecular weights were determined. It was demonstrated that high activities of endogenous enzymes (nucleases and proteases) in milts of hydrobionts correlated with the degree of hydrolysis of their nucleic acids.
Chitosan Depolymerization by Enzymes from the Hepatopancreas of the Crab Paralithodes camtschaticus by V. Yu. Novikov; V. A. Mukhin (pp. 464-468).
An enzyme preparation was isolated from the hepatopancreas of Paralithodes camtschaticus thatexhibited chitinase and chitosanase activities. Treatment of chitin and chitosan with this preparation decreased their viscosity-average molecular weights by 96 and 41%, respectively. The chromatographic profiles of the products of chitin and chitosan hydrolysis suggested that the crab hepatopancreas is rich in endochitinases. Enzymatic digestion of chitosan increased its solubility and moderately reduced the extent of its acetylation. A mathematical approach was proposed for calculating the molecular weights of chitosan fractions from weight-average molecular weights determined viscometrically.
Isolation and Characterization of Chitosanase from the Strain Bacillus sp. 739 by G. E. Aktuganov; A. V. Shirokov; A. I. Melent'ev (pp. 469-474).
The specific nature of the chitosanase activity of the strain Bacillus sp. 739 was determined. Maximum enzyme activity was observed in a medium containing biomass of the fruiting bodies of the fungus Macrolepiota procera. The chitosanase was purified to homogeneity by chromatography on DEAE-Sephadex A-50 and Toyopearl HW-50. The molecular weight of the enzyme assessed by electrophoresis (the Laemmli procedure) approximated 46 kDa. The temperature and pH optima of the purified chitosanase were in the ranges 45–55°C and 6.0–6.5, respectively. Time to half-maximum inactivation of the enzyme at 50°C was equal to 1 h. With colloidal chitosan as the substrate, the value of K М of the purified chitosanase was equal to 25 mg/ml. The enzyme also exhibited a weak ability to hydrolyze colloidal chitin.
O-Glycosylhydrolases of Marine Filamentous Fungi: β-1,3-Glucanases of Trichoderma aureviride by Yu. V. Burtseva; N. S. Verigina; V. V. Sova; M. V. Pivkin; T. N. Zvyagintseva (pp. 475-481).
The ability to produce extracellular O-glycosylhydrolases was studied in 14 strains of marine filamentous fungi sampled from the bottom sediments of the South China Sea. The following activities were detected in the culture liquids of the fungi: N-acetyl-β-D-glucosaminidase, β-D-glucosidase, β-D-galactosidase, β-1,3-glucanase, amylase, and pustulanase. β-1,3-Glucanases were isolated by ultrafiltration, hydrophobic interaction chromatography, and ion exchange chromatography, and their properties were studied. Data on products of enzymatic digestion of laminaran, absence of transglycosylation activity, and the pattern of action of natural inhibitors confirmed that β-1,3-glucanase belonged to the exo type. Inhibitor analysis demonstrated the role of a thiol group and tryptophan and tyrosine residues in the catalytic activity.
Comparative Stability Assessment of Laccases from the Basidiomycetes Coriolus hirsutus and Coriolus zonatus in the Presence of Effectors by E. V. Stepanova; O. V. Koroleva; V. P. Gavrilova; E. O. Landesman; A. Makower; D. B. Papkovsky (pp. 482-487).
Stability characteristics of the laccases of the basidiomycetes Coriolus hirsutus and Coriolus zonatus were measured comparatively at temperatures of 25 and 40°C in the presence of various effectors (proteins, salts, polyalcohols, polyacids, and polyelectrolytes). Stabilization effects of cations on the laccases from C. hirsutus and C. zonatus decreased in the descending series Cu2+ > Mg2+ > Ca2+ and Ca2+ > Mg2+ > Mn2+, respectively. Tween 20 caused insignificant stabilization of the two enzymes. The C. zonatus laccase was also insignificantly stabilized as a result of treatment with bovine serum albumin. The enzymatic activity of the laccase preparations from C. hirsutus and C. zonatus was conserved virtually completely after vacuum drying (84 and 93%, respectively). The most effective stabilizer of the C. hirsutus laccase was found to be dextran (17 kDa). Dry preparations treated with this agent conserved up to 95% of the enzymatic activity. The most effective stabilizer of the C. zonatus laccase was polyacrylic acid (102% of the initial activity).
Effect of Wood Modification on Lignin Consumption and Synthesis of Lignolytic Enzymes by the Fungus Panus (Lentinus) tigrinus by D. A. Kadimaliev; V. V. Revin; N. A. Atykyan; V. D. Samuilov (pp. 488-492).
Lignin consumption and synthesis of lignolytic enzymes by the fungus Panus (Lentinus) tigrinuscultivated on solid phase (modified and unmodified birch and pine sawdusts) were studied. The fungus grew better on and consumed more readily the birch lignin than the pine wood. Peroxidase activity was higher in the case of pine sawdust; laccase and lignolytic activities, in the case of birth sawdust. Treatment with ammonia or sulfuric acid decreased lignin consumption by this fungus cultivated on either medium. Modification of sawdust by ultrasound increased lignin consumption and may be recommended for accelerating biodegradation of lignocellulose substrates.
Screening and Mutagenesis of Aspergillus niger for the Improvement of Glucose-6-Phosphate Dehydrogenase Production by Jian-Zhong Liu; Qian-Ling Zhang; Li-Ping Weng; Liang-Nian Ji (pp. 493-496).
The Aspergillus niger strain ZBY-7 was selected as the original strain of glucose-6-phosphate dehydrogenase production. After mutagenesis of the strain by means of UV irradiation and nitrosoguanidine, mutants of Aspergillus niger resistant to a certain metabolic inhibitor were obtained. Five of the mutants showed increased glucose-6-phosphate dehydrogenase production. The mutant resistant to antimycin A (Aspergillus niger AM-23) produced the highest level of glucose-6-phosphate dehydrogenase (695.9% of that produced by the original strain).
Properties of 2-C-Methyl-D-Erythritol 2,4-Cyclopyrophosphate, an Intermediate in Nonmevalonate Isoprenoid Biosynthesis by D. N. Ostrovsky; G. R. Dyomina; Yu. I. Deryabina; A. V. Goncharenko; M. Eberl; K. B. Shumaev; A. S. Shashkov (pp. 497-502).
Extraction and purification from the biomass of Corynebacterium ammoniagenes of 2-C-methyl-D-erythritol 2,4-cyclopyrophosphate (MEC) was associated with its spontaneous transformation into a number of derivatives (which was due to the pyrophosphate bond lability and the formation of complexes with metals). These derivatives included 1,2-cyclophospho-4-phosphate, 2,4-diphosphate, 2,3-cyclophosphate, 1,4-diphosphate, and 3,5-diphosphate (identified by 1H, 31P, and 13C NMR spectroscopy) and accounted for about 10% of the MEC. When added to a solution of DNA in the presence of the Fenton reagent, MEC prevented DNA decomposition. In addition, MEC slowed down the interaction of the reagent with tempol radicals, which indicates that complexation of ferrous ions by MEC attenuates their ability to catalyze the formation of hydroxyl radicals from hydrogen peroxide. In the presence of 0.23 mM MEC, the rate of respiration of rat liver mitochondria increased by 1.8 times. At 0.1–1.0 mM, MEC activated in vitro proliferation of human Vgamma9 T cells. It is suggested that MEC acts as an endogenous stabilizing agent for bacterial cells subjected to oxidative stress and as an immunomodulator for eukaryotic hosts.
A New Type of Adaptation of the Cyanobacterium Spirulina platensis to Illumination Conditions by Yu. V. Bolychevtseva; L. E. Mazhorova; I. V. Terekhova; E. A. Egorova; A. G. Shugaev; M. G. Rakhimberdieva; N. V. Karapetyan (pp. 503-508).
Incubation of cells of the cyanobacterium Spirulina platensis under conditions of exposure to low-intensity (2–3 μE m–2 s–1) red light, which was predominantly absorbed by photosystem I (PS I), caused atypical adaptation changes. Invariable pigment composition and stoichiometry of the photosystems was observed in the cells incubated under these conditions against the background of a decrease in the rate of photosynthetic fixation of СО2 (by one-half) and a 1.5-fold increase in the rate of dark respiration relative to cells incubated under conditions of exposure to green light. Comparison of these data with a high rate of dark relaxation of P700+ in the presence of diuron suggests that deficiency of reduced equivalents on the donor side of PS I in Spirulina cells exposed to red light is compensated by electron supply from the respiratory chain NAD(P)H dehydrogenase complex.
Water-Soluble Galactomannan from the Seed of Ground Honeysuckle (Lotus corniculatus L.): Structure and Properties by A. V. Egorov; N. M. Mestechkina; R. Ya. Plennik; V. D. Shcherbukhin (pp. 509-511).
Galactomannan, a water-soluble heteropolysaccharide, was isolated from the seed of a Far Eastern population of the ground honeysuckle Lotus corniculatus L. (yield, 1.65%). Analysis of this galactomannan showed that it consists of D-mannose and D-galactose residues (molar ratio, 1.22 : 1). Its aqueous solutions were characterized by a specific rotation [α]D= +84.1° and intrinsic viscosity [η] = 559 ml/g. Analysis of this heteropolysaccharide using chemical and enzymatic procedures, as well as IR and 13C NMR spectroscopy, showed that its main chain comprises 1,4-β-D-mannopyranose residues, 95.5% of which are substituted at C-6 with single residues of α-D-galactopyranose.
Oligosaccharide Specificity of the Fucolectin from the Bark of Laburnum (Laburnum anagyroides) by V. E. Piskarev; M. D. Lutsik-Kordovskii; E. L. Piskareva; I. A. Yamskov (pp. 512-518).
A comparative study of fine carbohydrate specificity of the lectin from the bark of laburnum Laburnum anagyroides (LABA) and the fucolectin from asparagus pea Tetragonolobus purpureus (TPA) was performed using inhibition of agglutination of the complex formed by H-active neoglycoprotein and nanoparticles of colloidal gold. Both lectins bound most strongly the H type 2 oligosaccharides comprising O-glycans; however, LABA was almost unable to discriminate between them. LABA bound more weakly the H type 6 trisaccharide (Fucα1-2Galβ1-4Glc) and difucosyllactose (Fucα1-2Galβ1-4[Fucα1-3]Glc), a glucoanalogue of the Ley antigen, and, even more weakly, the Lea pentasaccharide lacto-N-fucopentaose II (Galβl-3[Fucαl-4]GlcNAcβl-3Galβl-4Glc). However, LABA did not bind the antigens Leb, Lec, and Led, very poorly interacted with the terminal Lex, and somewhat more strongly bound the internal Lex. The lectin also had a hydrophobic binding site. Both lectins exhibited a cluster effect with polymeric ligands (neoglycoproteins).
Preparation of Biologically Transformed Raw Material of Woolly Foxglove (Digitalis lanata Ehrh.) and Isolation of Digoxin Therefrom by V. S. Fonin; A. Ya. Khorlin (pp. 519-523).
A biotechnological approach is proposed for anaerobic conservation of aerial parts of woolly foxglove, followed by air–sun drying of the biologically transformed raw material. During the conservation, primary glycosides of foxglove undergo complete conversion into secondary glycosides, with no further transformations. A simple method is described for preparing an enriched glycoside fraction from the transformed raw material (yield, 3.6%) and for isolating highly purified digoxin from this fraction (yield, 0.06% of the starting raw material); other secondary glycosides can also be isolated.
Effects of Cytokinin Preparations on the Pools of Pigments and Proteins of Wheat Cultivars Differing in Their Tolerance to Water Stress by I. I. Chernyad'ev; O. F. Monakhova (pp. 524-531).
Contents of chlorophylls, carotenoids, soluble leaf proteins, and the key enzyme of carbon metabolism—ribulose bisphosphate carboxylase/oxygenase (RuBisCO; EC 4.1.1.39)—in young seedlings and adult leaves of the wheat Triticum aestivum L. cultivars Mironovskaya 808 and Lyutescens 758, contrasting in their water stress tolerances, were compared under conditions of normal available water supply, water deficiency, and subsequent rehydration. It was discovered that compounds displaying a cytokinin activity (6-benzylaminopurine, thidiazuron, kartolin-2, and kartolin-4) reduced the decreases in contents of chlorophylls, carotenoids, soluble leaf proteins, and RuBisCO, progressing with development of water stress, as well as contributed to their more rapid recovery. These compounds with cytokinin activity also accelerated restoration of the compounds studied to their initial concentrations during rehydration. The kartolin preparations caused a maximal protective effect. Water stress had a more pronounced negative effect on the cultivar Lyutescens 758. Dehydration resulted in a more extensive destruction of seedlings compared to leaves of adult plants.
Mineral Composition of Wild Onions and Their Nutritional Value by F. V. Golubev; N. A. Golubkina; Yu. N. Gorbunov (pp. 532-535).
Leaf accumulation of 11 microelements (Fe, Zn, Cu, Co, Mn, Ni, Pb, Cd, Sr, Cr, and Se) was studied in seven wild onion species of the genus Allium. A. flavescens Bess. accumulates five microelements (Cr, Ni, Cu, Zn, and Se) and also contains Fe, Co, and Mn at high concentrations. These features underlie the significant promise of this species as a means of procurement (nutritional adjustment of the content) of these microelements. The content of Cr in 100 g of leaves of this species is equivalent to 84% of the daily human need for this microelement. A. fistulosum L., A. odorum L., and the broad-leaved form of A. nutans specifically accumulate Cu, Zn, and Se. A. montanum Schmidt. is characterized by the accumulation of Zn. A. angulosum L. and A. schoenoprasum L. are characterized by the accumulation of Se. The broad-leaved forms of A. schoenoprasum L., A. nutans L., and A. odorum L. accumulate higher amounts of Zn and Cu than their narrow-leaved counterparts.