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Applied Biochemistry and Microbiology (v.37, #5)
Pathogen-Induced Plant Proteins (Review) by I. A. Tarchevsky (pp. 441-455).
Pathogen-induced plant proteins are classified according to their functional characteristics: involvement in plant cell signaling; inhibition of enzymes excreted by pathogens; stabilization of plant cell walls; ability to trigger apoptosis; enzymatic activity producing lysis of cell walls of pathogenic fungi and bacteria; enzymatic activity in metabolic pathways of phenylpropanoid and terpenoid phytoalexins; and ability to affect pathogens directly by disturbing the function of their cell membranes or by deactivating their ribosomes. Examples of transgenic plants with increased immunity against pathogens are also provided.
Role of Isoprenoids in Plant Adaptation to Biogenic Stress Induced by Parasitic Nematodes (Review) by S. V. Zinov'eva; Zh. V. Udalova; I. S. Vasil'eva; S. A. Vanyushkin; V. A. Paseshnichenko (pp. 456-463).
Parasitic nematodes are considered a biogenic stress factor in plants. The effects of various plant isoprenoids, including mono-, sesqui-, di-, and triterpenoids, sterols, and steroid glycosides, on parasitic nematodes are reviewed. Certain isoprenoids can be placed in the class of natural plant adaptogens.
Biodegradation of Oil Products by Individual Degrading Strains and Their Associations in Liquid Media by L. M. Baryshnikova; V. G. Grishchenkov; M. U. Arinbasarov; A. N. Shkidchenko; L. M. Boronin (pp. 463-468).
The degrading activities of selected bacterial strains and their associations directed towards fuel oil and diesel fuel in liquid media were studied. Two-member associations composed preferably by RhodococcusandPseudomonasstrains demonstrated the highest degrading efficiencies. No enhancement was achieved when the number of association members was increased to three, four, or five strains. The population stability of any member strain was found to depend on the association composition.
Extracellular Metabolites of Hydrocarbon-Oxidizing Bacteria as Substrates for Sulfate Reduction by T. V. Koronelli; T. I. Komarova; O. V. Porshneva; L. F. Tkebuchava (pp. 469-472).
The relationship between bacterial oxidation of hydrocarbons and sulfate reduction was studied in an experimental system with liquid paraffin used as a source of organic compounds inoculated with silt taken from a reservoir. Pseudomonads dominated in the hydrocarbon-oxidizing silt bacteriocenosis. However, Rodococcusand Arthrobacteria amounted to no more than 3%. Arthrobacteria dominated the microbial association formed in the paraffin film of the model system. Sulfate-reducing bacteria were represented by genera Desulfomonas, Desulfotomaculum, and Desulfovibrio. The growth of sulfate-reducing bacteria in media containing paraffin, successive products of its oxidation (cetyl alcohol, stearate, and acetate), and extracellular metabolites of hydrocarbon-reducing bacteria was studied. The data showed that sulfate-reducing bacteria did not use paraffin or cetyl alcohol as growth substrates. However, active growth of sulfate-reducing bacteria was observed in the presence of stearate and extracellular water-soluble or lipid metabolites of Arthrobacteria.
Characterization of Lipoxygenase from Fungi of the Genus Mortierella by S. Yu. Filippovich; Yu. A. Rybakov; T. P. Afanasieva; G. P. Bachurina; G. P. Lukina; I. E. Ezhova; A. V. Nosova; T. V. Artjushkina; S. P. Sineokii; M. S. Kritskii (pp. 473-479).
The specific activity of lipoxygenase from several strains of the zygomycete Mortierellavaried from 1.02 to 2.02 μmol diene per min per mg protein. The enzyme equally used linoleic or arachidonic acid as a substrate. An increase in lipoxygenase activity was observed after adding corn oil to the culture medium. Tests with inhibitors having different chemical structures revealed that the lipoxygenase activity from Mortierellacells was inhibited only by esculetin, ethanol, and nordihydroguaiaretic acid (NDGA). NDGA inhibited the enzyme in vitro(IC50=142 μM), but its addition in the exponential phase of growth activated the enzyme.
Formation of Extracellular Enzyme Systems during the Growth of Geotrichum candidum3C on Cell Walls Isolated from Cereal Grain Coats by N. A. Rodionova; N. V. Dubovaya; L. I. Martinovich; A. M. Bezborodov (pp. 480-482).
The activities of extracellular systems of hemicellulases, pectinases, and cellulases was studied during a 72-h cultivation of Geotrichum candidum3C. The culture was grown on a medium containing 3% cell walls isolated from wheat grain coats, which served as the sole carbon source. Enzymes catalyzing the degradation of pectin substances (beet pectin, α-L-arabinan, and 1,4-β-D-galactan), as well as β-D-galactosidase and α-L-arabinofuranosidase involved in their hydrolysis, were formed first (4 h after the beginning of cultivation). Enzymes hydrolyzing 4-O-methyl-α-D-glucurono-β-D-xylan and sodium carboxymethyl xylan were also found in the culture liquid after 4 h of fungal growth. The contents of pectin-degrading and xylanolytic enzymes reached their maximum levels after 52–56 and 72 h of growth, respectively. Cellulolytic enzymes were detected after 8–28 h of cultivation. Enzymes degrading α-D-galacto-β-D-mannan were found 24 h after the beginning of growth; their content was maximum after 72 h of cultivation.
Conditions for Ethanol Production during Bioconversion of Cellulose-Containing Raw Material by N. V. Zyabreva; E. P. Isakova; V. V. Biryukov (pp. 483-488).
Several natural associations composed of thermophilic anaerobic bacteria capable of utilizing various cellulose materials at 60 ± 2°C and pH 6.0–7.0 were isolated from the sludge of Kamchatka geothermal springs. The rate of ethanol production (up to 1.7 g/l per day) and the concentration of ethanol in the medium (up to 1.2%), as well as the fermentation period (10–15 days), were determined under anaerobic conditions in the presence of cellulose, coniferous sawdust, newsprint, or paper pulp as a carbon source. Microorganisms were found that inhibited the production of ethanol. The initial pH value was found to influence both the ethanol production rate and ethanol/acetate ratio. A pH decrease from 7.0 to 5.0 led to a 6.7-fold increase in ethanol production and caused a 23.8-fold increase in the ethanol/acetate ratio.
Xylitol Production by a Culture ofCandida guilliermondii2581 by N. A. Zagustina; N. A. Rodionova; N. M. Mestechkina; V. D. Shcherbukhin; A. M. Bezborodov (pp. 489-492).
The yeast strain Candida guilliermondii2581 was chosen for its ability to produce xylitol in media with high concentrations of xylose. The rate of xylitol production at a xylose concentration of 150 g/l is 1.25 g/l per h; the concentration of xylitol after three days of cultivation is 90 g/l; and the relative xylitol yield is 0.6 g per g substrate consumed. The growth conditions were found that resulted in the maximum relative xylitol yield with complete consumption of the sugar: xylose concentration, 150 g/l; pH 6.0; and shaking at 60 rpm. It was shown that the growth under conditions of limited aeration favors the reduction of xylose.
Effects of Nutrient Media on the Composition of Free Amino Acids in Saccharomyces cerevisiae by E. A. Khalilova; Sh. A. Abramov (pp. 493-496).
The quantitative and qualitative compositions of free amino acids of the yeast Saccharomyces cerevisiaeY-503 cultivated in different nutrient media were studied by liquid chromatography. The yeast grown in a medium containing geothermal water was shown to accumulate more amino acids. During lyophilization, the stabilization of the physiological activity of the yeast in this nutrient medium was observed. The increased biological value of dry yeast was shown to depend on the content of free amino acids, including essential amino acids: arginine, histidine, leucine, isoleucine, lysine, threonine, serine, and phenylalanine.
Evaluation of the Kinetic Parameters of Trickle Bed Vapor Phase Bioreactors by A. A. Victorov; A. E. Kurlovich; I. S. Rogozhin; I. V. Ulezlo; V. O. Popov; A. M. Bezborodov (pp. 497-499).
The dependence of toluene elimination capacity on its load was determined in five small-scale reactors filled with glass beads carrying biocatalyst cells. With an increase in the operation time, the calculated maximum elimination capacity was shown to increase in parallel with the biomass density in the biocatalyst bed. A fivefold increase in the trickling rate did not affect the reactor performance. A simplified mathematical model for evaluating the minimal required biocatalyst bed volume at a certain loading was developed based on the experimental curve of elimination capacity versus loading.
Relationship between Celandine Isoquinoline Alkaloids, Macroelements, and Microelements by G. N. Buzuk; M. Ya. Lovkova; S. M. Sokolova; Yu. V. Tyutekin (pp. 500-505).
Numerous linear and nonlinear correlations between the contents of alkaloids and mineral elements in the aerial parts and roots of greater celandine (Chelidonium majusL.) were revealed by means of correlation and regression analyses. These relationships became more significant with the transition from the sum of alkaloids to individual groups or fractions, which included compounds of similar compositions. Mathematical models describing the regulation of alkaloid metabolism by some mineral elements (Ba, Mg, Sr, Co, Cr, Zn, etc.) were developed in the analytical form. These models were tested in experiments with geochemical modeling using Zn.
Plant Resistance Suppressors in the Pathosystem Formed by Potato and the Causal Agent of Late Blight by O. L. Ozeretskovskaya; N. I. Vasyukova; E. A. Perekhod; G. I. Chalenko; L. I. Il'inskaya; N. G. Gerasimova (pp. 506-511).
The properties and effects of two plant resistance suppressors (1,3-β-1,6-β-glucan and a pentasaccharide of xyloglucan origin) involved in the pathosystem of potato (Solanum tuberosum) and the causal agent of blight (Phytophthora infestans(Mont) de Bary) were compared. The microbial 1,3-β-1,6-β-glucan suppressed the defense response over a narrow concentration range (10–2M), whereas the plant pentasaccharide had a broad range of effective concentrations (10–12to 10–6M). In the pathosystem of potato and the causal agent of late blight, the β-glucan caused a local and race-specific suppressor effect on the plant host defense response. In contrast, the pentasaccharide caused both local and systemic suppression of potato resistance and the presence of terminal fucosyl residue in the xyloglucan oligosaccharine played a decisive role in its effect. The recognition of both suppressors by potato cell membrane sites is discussed.
Effects of Elicitors on the Accumulation of Proteinase Inhibitors in Injured Potato Tubers by T. A. Valueva; T. A. Revina; E. L. Gvozdeva; N. G. Gerasimova; L. I. Il'inskaya; O. L. Ozeretskovskaya (pp. 512-516).
The time course of accumulation and the composition of proteinase-inhibiting proteins in diffusates from potato tubers treated with elicitors such as salicylic, jasmonic, and arachidonic acids were studied. The 40-kDa reserve protein patatin and the chymotrypsin inhibitors, among which proteins of 24.6, 22.0, and 16.0 kDa were prevalent, accumulated in diffusates from potato tubers. Jasmonic and arachidonic acids activated the accumulation of the chymotrypsin inhibitors in tubers in response to the injury stress, whereas salicylic acid inhibited this process. The effects of jasmonic and arachidonic acids increased when their concentrations decreased to 10–6M. Salicylic acid inhibited this process. The data suggest an important role of the lipoxygenase metabolism in signal transduction of the anti-injury defense system in dormant potato tubers.
Effect of a Protein Polygalacturonidase Inhibitor from Apple Fruit Tissue on the Enzyme Released by Fungal Pathogens by E. M. Glinka; M. A. Protsenko; E. A. Bulantseva; E. G. Sal'kova (pp. 517-520).
A protein polygalacturonidase inhibitor isolated from fruit of the apple cultivars Antonovka and Mantuanskoe differently affects the polygalacturonidases of different phytopathogenic fungi. Three groups of fungi were recognized according to the sensitivity of their polygalacturonidases to the inhibitory effect. Storage of apples after harvesting is accompanied by changes in the inhibitor activity, and the time pattern of these changes depends on the cultivar. An increase in the inhibitor activity occurs concurrently with the elevation in ethylene release characteristic of the stage of elevated respiration (a climacteric increase). The data suggest that a decrease in the apple fruit resistance to microbes at the end of the storage period is related, along with other reasons, to a change in the activity of the protein polygalacturonidase inhibitor.
Effects of Growth Regulators on H+Translocation across the Membranes of Plasma Membrane Vesicles from Potato Tuber Cells by E. P. Ladyzhenskaya; N. P. Korableva (pp. 521-523).
Effects of the growth regulators epibrassinolide-694 (EB), gibberellic acid (GA), and abscisic acid (ABA) on the ATP-dependent translocation of H+through the membranes of plasma membrane vesicles of potato (Solanum tuberosumL.) tuber cells were studied. The ATP-dependent accumulation of H+in the plasma membrane vesicles from dormant tubers was inhibited by EB and ABA and stimulated by GA. After the break of dormancy, the stimulatory effect of GA increased, the inhibitory effect of ABA decreased, and EB stimulated the accumulation of H+in the vesicles. The data suggest that the plasma membrane H+ATPase is a target of phytohormones that regulate the dormancy of potato tubers.
Forms of Silicon in Medicinal Plants by M. P. Kolesnikov; V. K. Gins (pp. 524-527).
The contents of three forms of silicon (organic, soluble mineral, and polymeric) were determined in leaves of 21 medicinal plants. At a total content of silicon of 0.74 to 3.59%, the organic, soluble mineral, and polymeric forms accounted for 0.51–1.91%, 0.05–0.51%, and 0.1–1.21%, respectively. An analysis of silicon in the condensed polyphenol fraction was performed for the first time revealing the presence of a covalently bound form in amounts of 0.1 to 0.2% of the total silicon content in the leaves. These results are of interest for food or medical applications of the plants studied.
Aroma-Forming Substances from a Culture of the Mold Fungus Penicillium roquefortiGrown on Curd by A. V. Gerasimov; V. A. Dolmatov; Yu. S. Osledkin; V. V. Kochetkov (pp. 528-533).
Production of aroma-forming substances by Penicillium roquefortistrains No. 31 and No. 541-A grown on curd was studied. The data showed that strain No. 541-A is the most promising producer of cheese flavor. The flavor acquired a soily scent after more than 5 days cultivation, which may hamper the use of these cultures (particularly, No. 31) in the food industry.
Isolation and Partial Characterization of Lectin from the Venom of Vietnamese Scorpion Buthus occitanussp. by N. A. Hoang; B. B. Berezin; V. M. Lakhtin; I. A. Yamskov (pp. 534-537).
A lectin was isolated from the venom of scorpion Buthus occitanussp. by means of Sephadex G-50 gel filtration and CM-cellulose ion exchange chromatography. The homogeneous lectin preparation consisted of homodimeric molecules with a subunit M rof 9.3 kDa. Glycine, alanine, and serine dominated in the lectin amino acid composition. The lectin was a glycoprotein containing 20% carbohydrates (predominantly mannose and glucose). Trypsin-treated murine erythrocytes agglutinated at a lectin concentration of 32 μg/ml. Hemagglutination was inhibited by carbohydrates (L-fucose > D-glucose > L-rhamnose > D-xylose). The lectin revealed no phospholipase or hyaluronidase, nor toxic activity.
Enzymatic Hydrolysis of Proteins from Crustaceans of the Barents Sea by V. A. Mukhin; V. Yu. Novikov (pp. 538-542).
Enzymatic preparations from king crab hepatopancreas were shown to be capable, in principle, of producing protein hydrolysates. Hydrolysis of protein-containing waste of deep-water prawn and king crab occurs most successfully at pH 8.0–8.5 and 50–55°C for 5–6 h in the presence of 6 g enzyme per kg substrate. The total chemical composition of the hydrolysates, the molecular weight distributions of proteins and polypeptides, and the contents of free amino acids were studied in dry hydrolysates.
Rastitel'nyi belok: Novye Perspecktivy(Vegetable Protein: New Prospects), Braudo, E. E., Ed., Moscow: Pishchepromizdat, 2000
by V. M. Belikov (pp. 543-543).