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Applied Biochemistry and Microbiology (v.37, #2)
Involvement of Proteolytic Enzymes and Their Inhibitors in Plant Protection (Review) by V. V. Mosolov; L. I. Grigor'eva; T. A. Valueva (pp. 115-123).
The literature data on possible ways of involvement of proteolytic enzymes and their inhibitors in protection of plants from pests and disease are analyzed. Certain practical applications of natural protease inhibitors to plant protection are discussed.
The Kingdom Fungi: Heterogeneity of Physiological and Biochemical Properties and Relationships with Plants, Animals, and Prokaryotes (Review) by E. P. Feofilova (pp. 124-137).
This review analyzes the current taxonomy of fungi whose criteria are based on a range of episemantic molecules. In this context, data on the chemical composition of fungal cells (membrane lipids, cytosolic carbohydrates, etc.) are considered in comparison with their counterparts found in higher eukaryotes and prokaryotes. Modern theories explaining the origin of fungi and their similarity to plants, animals, and bacteria are discussed. The biochemical criteria used in this work supported the division of fungi into Eomycota and Neomycota. The latter division, especially Basidiomycota, are more closely related to plants. The heterogeneity of the Fungi kingdom is emphasized, the existence of Oomycota as a separate entity is supported, and the theory of the primitive nature of fungal cells is criticized from the viewpoint of biochemical adaptation.
Preparation of High-Purity Cyclodextrin Glucanotransferase from Bacillussp. 1070 by D. A. Volkova; S. A. Lopatin; I. M. Gracheva; V. P. Varlamov (pp. 138-141).
Two schedules have been developed for chromatographic purification of cyclodextrin glucanotransferase (CGTase) from a culture of Bacillussp. 1070. The purification on butyl-Toyopearl and on Cu(II)-iminodiacetic (IDA) agarose resulted in a 9.5-fold purification of the enzyme. The second schedule for purification (chromatography on butyl-Toyopearl and on DEAE-Sephacel) resulted in a 13.5-fold increase in the specific activity of CGTase. By electrophoresis under denaturing conditions, the enzyme purity was shown to be no less than 90%. According to preliminary data, CGTase consists of two isoenzymes with pI 5.1 and 5.3.
Depolymerization of Chitosan with a Chitinolytic Complex from Bacteria of the Genus Bacillussp. 739 by A. V. Il'ina; V. P. Varlamov; A. I. Melent'ev; G. E. Aktuganov (pp. 142-144).
Low-molecular-weight (3–6 kDa) water-soluble chitosan was obtained by enzymatic depolymerization. Hydrolysis of crab chitosan was induced by O-glycoside hydrolase (EC 3.2.1), the extracellular chitinolytic complex from Bacillussp. 739. The optimum conditions for hydrolysis were found (sodium–acetate buffer, pH 5.2; 55°C; and an enzyme/substrate ratio of 4 U per g chitosan; 1 h).
Identification of Catalytically Active Groups of Wheat Germ Lipoxygenase by N. A. Zherebtsov; T. N. Popova; T. V. Zyablova (pp. 145-149).
Dependences of lipoxygenase activity on pH, ionization enthalpies of various chemical groups, photoinactivation of the enzyme, and effects of specific reagents (p-CMB, DPF, and PMSF) were studied to identify catalytically active groups of the enzyme. The data suggest that the catalytic site of lipoxygenase includes imidazole and hydroxyl groups of histidine and serine residues, respectively.
Phosphatase from Proteus mirabilis by Z. Z. Salikhova; R. B. Sokolova; D. V. Yusupova (pp. 150-154).
Cell-free preparations of Proteus mirabiliscontained a phosphatase (EC 3.1.3.1) whose activity surpassed that of alkaline phosphatase from Escherichia coli. Phosphatase was also found in the culture liquid of P. mirabilis. The composition of proteins displaying enzyme activity was assayed by polyacrylamide gel electrophoresis. Enzyme synthesis was studied at various stages of bacterial growth. Biosynthesis of phosphatase in P. mirabilis(similarly to that found in other bacteria) was shown to be induced under conditions of inorganic phosphate deficiency in the medium.
Degradation of Petroleum Oils by a Selected Microbial Association by A. Yu. Muratova; O. V. Turkovskaya (pp. 155-159).
A series of microbial associations capable of the biodegradation of various petroleum oils, emulsols, and crude oil were obtained by selection during periodic or continuous cultivation. Formation of the associations and oil-product degradation occurred most efficiently during aerobic flow cultivation. Under these conditions, oils were degraded by 92% on average. The microbial degradation of a petroleum oil depended on its brand, concentration, emulsification, and aeration.
Sequential Isolation of Superoxide Dismutase and Ajmaline from Tissue Cultures of Rauwolfia serpentinaBenth by N. V. Kirillova; M. G. Smirnova; V. P. Komov (pp. 160-163).
Two biologically active compounds, the enzyme superoxide dismutase (EC 1.15.1.1) and the anti-arhythmic indole alkaloid ajmaline, were isolated from a callus culture of Rauwolfia serpentinaBenth. Sequential isolation of biologically active compounds by metal–chelate affinity chromatography followed by azoadsorbent affinity chromatography allowed us to obtain highly purified products. The yields of superoxide dismutase and ajmaline were 180 mg/kg biomass and 16.5 g/kg dry weight, respectively.
Assimilation of Propane and Characterization of Propane Monooxygenase from Rhodococcus erythropolis3/89 by A. K. Kulikova; A. M. Bezborodov (pp. 164-167).
The ability of propane-assimilating microorganisms of the genus Rhodococcusto utilize metabolites of the terminal and subterminal pathways of propane oxidation was studied. Propane monooxygenase of Rhodococcus erythropolis3/89 was shown to be an inducible enzyme catalyzing epoxidation and hydroxylation of organic compounds. The optimum conditions for the epoxidation of gaseous and liquid alkenes and the hydroxylation of aromatic carbohydrates were found.
Urease Inhibition by Polymeric Substrate Analogues and Thiophosphamides by D. I. Metelitsa; E. I. Tarun; A. V. Puchkaev; Yu. P. Losev (pp. 168-173).
Inhibition of soybean urease by polymeric substrate analogues, urea and thiourea polydisulfides (PDSU and PDSTU, respectively); or three thiophosphoric acid amides (TPAA), tri-(N-3-hydroxyphenyl)thiophosphamide (1), tri-(N-4,4"-aminodiphenyl)thiophosphamide, and di-oxy-(N-α-piridyl)thiophosphamide (3) was studied in aqueous solutions at various pH values. The inhibitory effects of all these substances were reversible and competitive with the lowest inhibition constant K i2.8 μM for TPAA-1 at pH 3.85. Above and below this pH value, K iincreased, reaching 24 μM at pH 7.2. All test substances inhibited urease comparably with known inhibitors such as thiols (cysteamine, etc.) and hydroxamic acid derivatives, but were less efficient than phosphorodiamidates. Structural features of possible urease inhibitors of higher efficiency were proposed.
Coimmobilization of Lactate Dehydrogenase and Low-Molecular-Weight Thiols on Sepharose by M. Yu. Yazykova; V. I. Muronets (pp. 174-177).
Lactate dehydrogenase (EC 1.1.1.27) and dithiothreitol (DTT) were coimmobilized on Sepharose activated with cyanogen bromide. It was demonstrated that the addition of 10 mM DTT (but not 2-mercaptoethanol) during immobilization increased the enzyme specific activity 1.5–5-fold depending on the initial extent of Sepharose activation by cyanogen bromide. The total activity increased two- to threefold. The lactate dehydrogenase preparations were rich in matrix-immobilized sulfhydryl groups (1.8–13.0 nmol per ml gel). The presence of DTT increased the stability of immobilized lactate dehydrogenase.
Preparation and Characterization of Immobilized Aspergillus awamori466 Glucoamylase by I. D. Ruadze; N. A. Zherebtsov; Yu. I. Slepokurova; V. F. Selemenev; I. V. Shkutina; O. F. Stoyanova (pp. 178-183).
Glucoamylase from Aspergillus awamori466 was immobilized on various supports. The enzyme sorption depends on its amount, the type of support, and immobilization conditions. The kinetics of acidic inactivation of the native and immobilized enzyme was studied. The immobilized enzyme was more resistant to temperature and pH. The mechanism of the enzyme binding to the support was investigated by IR spectroscopy.
Minor Alkaloids of the Fungus Penicillium roquefortiiThom 1906 by N. G. Vinokurova; D. M. Boichenko; B. P. Baskunov; N. F. Zelenkova; I. G. Vepritskaya; M. U. Arinbasarov; T. A. Reshetilova (pp. 184-187).
New isomers of clavine alkaloids with distinctively low chromatographic mobilities were isolated from the collection and mutant strains of Penicillium roquefortiiThom 1906, in addition to alkaloids roquefortine, 3,12-dihydroroquefortine, isofumigaclavines A and B, festuclavine, and chanoclavine-I, which are characteristic of this species. It was demonstrated that the collection strain produces isomers of agroclavine and epoxyagroclavine, whereas the mutant strain synthesizes isomers of fumigaclavines A and B, festuclavine, and chanoclavine.
Chicoric and Chlorogenic Acids in Plant Species from Georgia by I. D. Chkhikvishvili; G. I. Kharebava (pp. 188-191).
Chicoric acid was isolated from dandelion (Taraxacum officinaleWigg.) leaves by column chromatography. Conditions for HPLC analysis of chicoric and chlorogenic acids were optimized. These acids were assayed in some plants growing in Georgia. The optimum conservation temperature for the preservation of chicoric and chlorogenic acids in the leaves of dandelion and bilberry (Vaccinium arctostaphylosL.) was determined.
The Effect of Nutrient Medium Composition on Peroxidase Biosynthesis by Bazidiomycete Pleurotus ostreatus, strain UzBI-I105 by L. A. Kuz'mina; Z. R. Akhmedova; K. D. Davranov (pp. 192-194).
Production of extracellular peroxidase was studied during the submerged cultivation of xylotrophic bazidiomycete Pleurotus ostreatus, strain UZBI-I105 in nutrient media with lignocellulosic wastes, exhausted cottonseed oil cake, cotton stalks, rice husks, or ambary hemp. Enzyme production was enhanced 3–5 times in the presence of exhausted cottonseed oil cake extract in the nutrient medium. The dynamics of peroxidase production in various media was investigated.
A Method for Producing Multiple Forms of Metleghemoglobin Reductase and Leghemoglobin Components from Lupine Nodules by S. V. Shleev; F. N. Rozov; A. F. Topunov (pp. 195-200).
A method for producing simultaneously homogeneous preparations of two main forms of metleghemoglobin reductase and major leghemoglobin components from lupine nodules was developed. The method involves salting out with ammonium sulfate at 40–80% saturation, gel filtration on Ultrogel AcA 44, and double isoelectric focusing. The homogeneous metleghemoglobin reductase forms with molecular weights of 62 and 66 kDa were purified 725- and 402-fold, respectively. The total yield with respect to activity equaled 37%. The 62-kDa form was more active.
Isolation, Purification, and Characterization of Acetolactate Synthase from a Lactococcus lactis Culture by Yu. S. Kisrieva; V. M. Serebrennikov; E. V. Eneiskaya; N. A. Zagustina; A. M. Bezborodov (pp. 201-205).
Acetolactate synthase catalyzing the synthesis of α-acetolactate was isolated from lactic acid bacteria Lactococcus lactissubsp. lactisbiovar. diacetylactis4 and purified. Acetolactate synthase was shown to be an allosteric enzyme with low affinity for the substrate: the K Mfor pyruvate was 70 mM. The curve relating the dependence of enzyme activity to pyruvate concentration had a sigmoid shape. The enzyme activity persisted for 24 h in the presence of stabilizers, pyruvate, and thiamine pyrophosphate. Acetolactate synthase had pH optimums of 5.8 and 6.5–7.0 in acetate and phosphate buffers, respectively. The temperature optimum for this enzyme was 38–40°C at pH 6.5. The molecular weight of acetolactate synthase was 150 kDa. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate showed that the enzyme consisted of three identical subunits with a molecular weight of 55 kDa.
Visualization of Fruit Odor by Photoluminescence by A. A. Kharlamov; H. Burrows (pp. 206-214).
Photoluminescence with visible emission spectrum was observed and visualized at the surface of certain fruits. This photoluminescence is associated with vapors of natural organic volatiles (odorants) emitted from the fruit surface. The photoluminescence spectra of various fruits (apple, pear, kiwi, and strawberry) were measured in vivo using a number of fluorometric methods. Fruit aging was found to be accompanied by modification of the photoluminescence spectrum shape and a noticeable increase in the photoluminescence intensity. Laser photoluminescence microscopy in vapors of fruit extracts and artificial compounds was used to assess the contribution of various substances to natural odor emission of fruits. The results of this study show that fluorometry of odors is a promising method for studying fruits and other objects.
Identification and Quantification of Ascorbic Acid in Kiwi Fruit by High-Performance Liquid Chromatography by G. I. Kvesitadze; A. G. Kalandiya; S. G. Papunidze; M. R. Vanidze (pp. 215-218).
The content of ascorbic acid in kiwi fruit (Actinidia chinensisPlanch) of various cultivars was determined by high-performance liquid chromatography (HPLC). A minimal content of ascorbic acid was found in fruits of Gaivard cultivar: in juice – 5.44, skin – 1.14, and pulp – 4.20 mg/g.
Electrooptical Properties of Cells of the Soil Nitrogen-Fixing Bacterium Azospirillum brasilense: Effects of Copper Ions by O. V. Ignatov; A. A. Kamnev; L. N. Markina; L. P. Antonyuk; M. Colina; V. V. Ignatov (pp. 219-223).
The effects of copper ions on the uptake of some essential metals in the biomass and the electrooptical properties of cell suspensions of the nitrogen-fixing soil bacterium Azospirillum brasilensesp. 245 were studied. Copper cations were shown to be effectively taken up by the cell biomass from the culture medium. The addition of copper ions increased the rate of uptake of some other metals present in the culture medium. This was accompanied by changes in the electrooptical characteristics of cell suspension as measured within the orienting electric field frequency range of 10 to 10 000 kHz. The effects observed during short-term incubation of A. brasilensein the presence of copper cations were less significant than during long-term incubation. These results can be used for the rapid screening of microbial cultures for the enhanced efficiency of sorption and the uptake of metals.
L.I. Vorobiova, Propionibacteria, Kluver Academic Publishers, Dordrecht–Boston–London, 1999
by A. M. Bezborodov (pp. 225-225).
The International Symposium “Modern Problems of Microbial Biochemistry and Biotechnology”
by L. P. Lichko (pp. 226-227).