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Applied Biochemistry and Microbiology (v.39, #1)
Deceleration of Vital Activity as a Universal Biochemical Mechanism Ensuring Adaptation of Microorganisms to Stress Factors: A Review by E. P. Feofilova (pp. 1-18).
The review deals with a major problem of contemporary biology, i.e., the strategy of persistence of organisms affected by stressors. The primary mechanism of biochemical adaptation of cells is their transition to a specific surviving state, which is characterized by deceleration of vital activity (DVA), a process related to decreased metabolism. According to the latest classification, there are four types of DVA: quiescence (endogenous or exogenous), cryptobiosis, anabiosis, and latent life. These states are viewed from a new standpoint, depending on both the stage of growth and development of the organism and the type of stressor. A brief characterization of cryptobiosis and anabiosis is provided. Quiescence, which is a specific type of DVA, is characterized in greater detail, with emphasis on differences between fungi and bacteria. Endogenous and exogenous quiescence is compared in two types of cells (spores). Changes in the composition of quiescent cells (spores) as compared to their vegetative counterparts involve lipids (membrane-associated and neutral), cytosolic carbohydrates (which serve as a reserve supply of nutritients or act as protectors), water content, RNA and protein synthesis, and cyclic nucleotides (e.g., cAMP). Biochemical mechanisms controlling reversion of DVA (the transition from spores to germinating cells) are also analyzed. In conclusion, consideration is given to the role of DVA in evolution and to the implications of DVA studies for biotechnology, cryogenic preservation, and utilization of interstellar space and permafrost territories.
Estimation of the Hydrocarbon-Oxidizing Activity of Microorganisms by S. B. Petrikevich; E. N. Kobzev; A. N. Shkidchenko (pp. 19-23).
A method allowing microorganisms growing on substrates with low water solubility (oil, fuel oil, resins, and asphalthenes) to be isolated and counted was developed. The method makes it possible to estimate the oil-utilizing activity of each strain visually according to the decolorized zones formed during its growth on oil products. The sizes of these zones indicate which oil-degrading strains are most active.
Resistance of Penicillium piceum F-648 to Hydrogen Peroxide under Short-Term and Prolonged Oxidative Stress by Zh. I. Pavlovskaya; R. V. Mikhailova; I. V. Moroz; A. N. Eremin (pp. 24-29).
Resistance of Penicillium piceumF-648 to hydrogen peroxide under short-term and prolonged oxidative stress was studied. An increase in the activity of intracellular catalase in fungal cells after short-term exposure to hydrogen peroxide was shown. Activation of fungal cells induced by H2O2 depends on the H2O2 concentration, time of exposure, and growth phase of the fungus. Variants of P. piceum F-648 that produced two forms of extracellular catalase with different catalytic properties were obtained due to prolonged adaptation to H2O2. Catalase with low affinity for substrate was produced predominantly by the parent culture and variant 3; however, a high substrate affinity of catalase was observed in variant 5. Variant 5 of P. piceum F-648 displayed a high catalytic activity and operational stability of catalase in the presence of phosphate ions and a concentration of substrate less than 30 mM at pH more than 7.
Genetic Aspects of the Relationship between Isoquinoline Alkaloids and Mineral Elements in Greater Celandine (Chelidonium majus L.) by G. N. Buzuk; M. Ya. Lovkova; S. M. Sokolova; Yu. V. Tyutekin (pp. 30-35).
Interrelations between the total content of isoquinoline alkaloids, the concentrations of quaternary protoberberines and benzophenanthridines, and the amount of K, Cu, Co, Al, Ba, and Zn in aerial parts of individual celandine plants were revealed, within a single cenopopulation, using correlation analysis and regression analysis. Mathematical models describing the regulation of isoquinoline metabolism by some of the mineral elements were obtained in analytical form. The results suggest that this process is genetically determined.
Evaluation of the Effects of Biological Preparations on Phytopathogenic Fungi Didymella applanata and Botrytis cinerea by T. V. Shpatova; M. V. Shternshis; A. A. Belyaev (pp. 36-39).
Fungicidal and fungistatic effects of biological preparations involving bacteria of the genera Pseudomonas and Bacillusand fungi of the genusChaetomium on phytopathogenic fungi Didymella applanata and Botrytis cinereawere evaluated. All the biological preparations under study inhibited the growth of colonies of the fungi; however, the degree of the inhibition depended on the nature of each particular microorganism and the concentration of each particular preparation. A preparation containing Bacillus subtilis at a concentration of 0.2% effected maximum suppression ofB. cinerea (the diameter of the colonies decreased sevenfold). Preparations containing bacteria of the genus Pseudomonas and fungi of the genus Chaetomium were most efficient in suppressing D. applanata.Preparations containingB. subtilis and Chaetomium spp. showed promise as agents against simultaneous development of spur blight and Botrytis blight.
Conditions for Cultivation of the Fungus Penicillium melinii UzLM-4 and Its Biosynthesis of Lipases by A. A. Makhsumkhanov; I. T. Yakubov; K. Davranov (pp. 40-43).
Cultivation of the fungus Penicillium melinii UzLM-4 on a Raistrick's medium of our own modification made it possible to increase the biosynthesis of lipases by three to four times. The following conditions ensured a high rate of synthesis of the extracellular lipase: age of the inoculum, 15 days; concentration of the inoculum, 15 × 106 conidia per 100 ml medium; initial pH of the nutrient medium, 8.0; and cultivation in a shaker at 150 rpm and 25°C.
Analysis of Secondary Metabolites of Microscopic Fungi of the Genus Penicillium by Chromatographic Techniques by N. F. Zelenkova; N. G. Vinokurova; M. U. Arinbasarov (pp. 44-54).
Combinations of various systems of thin-layer chromatography and high-performance liquid chromatography (HPLC) were efficient in analyzing 39 nitrogen-containing secondary metabolites (alkaloids) produced by 12 strains of microscopic fungi of the genus Penicillium. Chromatographic mobility of alkaloids on Silufol plates was determined in the following systems: (a) chloroform, methanol, and 25% NH4OH (90 : 10 : 1, 90 : 10 : 0.1, or 80 : 20 : 0.2); (b) chloroform and acetone (9 : 1); and (c) ethyl acetate, methanol, and 25% NH4OH (85 : 15 : 10); staining was performed using Ehrlich's reagent. Conditions for separation of clavine alkaloids by HPLC on Spherisorb ODS-2 and Supelcosil LC-18 columns (gradient elution) were optimized. Retention values of 22 alkaloids were compared to those of agroclavine and roquefortine.
Effects of Nitriles and Amides on the Growth and Nitrile Hydratase Activity of the Rhodococcus sp. Strain gt1 by A. Yu. Maksimov; M. V. Kuznetsova; G. V. Ovechkina; S. V. Kozlov; Yu. G. Maksimova; V. A. Demakov (pp. 55-59).
Effects of some nitriles and amides, as well as glucose and ammonium, on the growth and the nitrile hydratase (EC 4.2.1.84) activity of the Rhodococcus sp. strain gt1 isolated from soil were studied. The activity of nitrile hydratase mainly depended on the carbon and nitrogen supply to cells. The activity of nitrile hydratase was high in the presence of glucose and ammonium at medium concentrations and decreased at concentrations of glucose of more than 0.3%. Saturated unsubstituted aliphatic nitriles and amides were found to be a good source of nitrogen and carbon. However, the presence of nitriles and amides in the medium was not absolutely necessary for the expression of the activity of nitrile hydratase of the Rhodococcus sp. strain gt1.
Composition and Biological Activity of Submerged Mycelium of the Xylotrophic Basidiomycete Lentinus edodes by A. G. Lobanok; V. G. Babitskaya; L. V. Plenina; T. A. Puchkova; O. V. Osadchaya (pp. 60-64).
The composition of submerged mycelium of Lentinus edodesgrown in laboratory fermenters was studied. The mycelium contained 23–24% proteins, 8–9% lipids, up to 1.8% phenolic substances, and a significant amount of inorganic substances, including calcium and iron. The fungus produced up to 5.0% intracellular and 3.5–4.0 g/l extracellular polysaccharides. The submerged mycelium stimulated the development of humoral immune response elicited by sheep red blood cells.
Fungal Decomposition of Oat Straw during Liquid and Solid-State Fermentation by E. V. Stepanova; O. V. Koroleva; L. G. Vasilchenko; K. N. Karapetyan; E. O. Landesman; I. S. Yavmetdinov; Yu. P. Kozlov; M. L. Rabinovich (pp. 65-74).
White rot fungi (Coriolus hirsutus, Coriolus zonatus, and Cerrena maxima from the collection of the Komarov Botanical Institute of the Russian Academy of Sciences) and filamentous fungi (Mycelia sterilia INBI 2-26 and Trichoderma reesei6/16) were grown on oat straw–based liquid and solid media, as well as in a bench-scale reactor, either individually or as cocultures. All fungi grew well on solid agar medium supplemented with powdered oat straw as the sole carbon source. Under these conditions, the mold Trichoderma reesei fully suppressed the growth of all basidiomycetes studied; conversely,Mycelia sterilia neither affected the development of any of the cultures, nor did it show any substantial susceptibility to suppression by their presence. Pure solid cultures of basidiomycetes, as well as the coculture of Coriolus hirsutus andCerrena maxima,caused a notable bleaching of the oat straw during its consumption. When grown on the surface of oat straw–based liquid medium, the basidiomycetes consumed up to 40% of the polysaccharides without measurable lignin degradation (a concomitant process). Under these conditions, Mycelia sterilia decomposed no more than 25% of the lignin in 60 days, but this was observed only after polysaccharide exhaustion and biomass accumulation. In contrast, during solid-state straw fermentation, white rot fungi consumed up to 75% of cellulose and 55% of lignin in 83 days (C. zonarus), whereas the corresponding consumption levels for cocultures ofMycelia sterilia and Trichoderma reesei equaled 70 and 45%, respectively (total loss of dry weight ranged from 55 to 60%). Carbon dioxide–monitored solid-state fermentation of oat straw by the coculture of filamentous fungi was successfully performed in an aerated bench-scale reactor.
Comparative Analysis of Models Describing Interactions between Antibodies and Liposomal Antigens by O. D. Hendrickson; A. V. Zherdev; A. P. Kaplun; B. B. Dzantiev (pp. 75-81).
Mathematical models of three levels of complexity are proposed that describe the interactions between antibodies and polyvalent liposomal antigens. The models take into account the contribution of high-affinity bivalent complexes and clusters of several antigenic groups to the immunochemical reaction. The models were analyzed numerically at different values of thermodynamic and kinetic parameters of the antigen–antibody reaction. The conditions under which models of different levels of complexity provide a satisfactory description of the antigen–antibody interaction were determined. The adequacy of the results of modeling was confirmed experimentally in liposomal preparations differing from each other by the surface density of a monovalent hapten (atrazine) conjugated with a lipid.
Biological Oxidation of Sulfide Raw Material Using a Culture of Thiobacillus ferrooxidans under Various Conditions of Leaching by N. V. Fomchenko; O. V. Slavkina; V. V. Biryukov (pp. 82-86).
Major parameters of the first stage of leaching of a copper–zinc sulfide product (raw material) by a culture of Thiobacillus ferrooxidans have been studied, including the effects of solid-phase concentration, Fe2+ and Fe3+ ions, pH, and the intensity of mixing. The first stage of leaching of the sulfide raw material is optimum under the following conditions: pH of the original leaching solution equal to 1.6; Fe3+ concentration of the order of 10 g/l; and vigorous mixing of the suspension at solid-phase concentrations of 30–35%. A theoretical substantiation of the observed dependences is proposed.
Determination of Carboxylic Acids in Wines by Liquid Ion-Exclusion Chromatography by I. V. Seliverstova; A. A. Ivanov; L. A. Ivanova (pp. 87-89).
The chromatographic behavior of aromatic and aliphatic acids was studied using an ion-exclusive column. The conditions were determined under which the separation of the acids by single-column ion-exclusion chromatography with UV detection was the most selective and efficient. The method developed was employed for determining the content of carboxylic acids in wines.
Effect of the Structure of Alcohols on Their Binding by Thermotropic Gels of Cornstarch by T. A. Misharina; A. L. Samusenko; M. A. Kalinchenko (pp. 90-93).
Binding of alcohols by thermotropic gels of normal corn starch was studied using the method of capillary gas–liquid chromatography. The amount of the gel-bound substances depended linearly on their concentrations in the original gel. Binding of n-alcanols increased with the length of the alkyl chain, exhibiting a linear dependence. The binding was attenuated by the presence of double bonds, cyclic substituents, or branching in the carbon chain. Binding of alcohols by starch polysaccharides was more pronounced in thermotropic gels, as compared to cryotextured gels. Binding isotherms were indicative of cooperative interactions in which alcohols formed supramolecular structures with hydrated molecules of polysaccharides and inclusion complexes with amylose and side chains of amylopectin.
Study of Oligosaccharide Specificity of Perch Roe Fucolectin Using Gold-Labeled Neoglycoproteins by V. E. Piskarev; O. Yu. Preisel; R. P. Evstigneeva; I. A. Yamskov (pp. 94-98).
The specificity of perch (Perca fluviatilis) roe fucolectin was studied using the protein dot blot technique, followed by detection with colloidal gold–labeled neoglycoproteins bearing human milk oligosaccharides. The strongest binding was noted with the H type 1 pentasaccharide lacto-N-fucopentaose (Fucα1-2Galβ1-3GlcNAcβ1-3Galβ1-4Glc); the interaction with the H type 6 trisaccharide 2"-fucosyllactose (Fucα1-2Galβ1-4Glc) was weaker. Binding of the perch lectin to the Lewis antigens (associated with tumors and embryonic tissues) was also studied. It was found that the lectin weakly interacted with the hexasaccharide lacto-N-difucohexaose I, Leb (Fucα1-2Galβ1-3[Fucα1-4]GlcNAcβ1-3Galβ1-4Glc), but not with Lea, Lec, or Lex antigens. Thus, the perch roe lectin exhibited pronounced differences in carbohydrate specificity from other fucolectins—a feature that may be used in structural studies and isolation of fucose-containing glycoconjugates.
Role of Trophic and Hormonal Factors in Exogenous Regulation of the Formation of Reproductive Organs in Yellow Lupine (Lupinus luteusL.) by A. I. Zabolotnyi; N. P. L'vov; V. A. Khripach; N. N. Kudryashova (pp. 99-104).
During the formation and ripening of beans in yellow lupine, their intactness may be increased by treatment of the plants with the microelement molybdenum or the growth factor 24-epibrassinolide. Early stages of the effects of either factor involved activation of various metabolic pathways, which differ in each case; eventually, the supply of fruit elements with free amino acids was improved and the seed productivity of the plants was increased.
Specific Features of Albumin Interactions with Hemiacetals of Aflatoxins and Sterigmatocystin by G. P. Kononenko; A. A. Burkin; N. A. Soboleva (pp. 105-110).
Aflatoxin B2a (AB2a), aflatoxin G2a (AG2a), and the hemiacetal of sterigmatocystin have been shown to form immunoreactive conjugates with albumin. The conjugates were formed following incubation of solution mixtures at room temperature for 1 h, as demonstrated by spectrophotometry and enzyme immunoassay. Anti-AB2a antibodies reacted with AB2a, aflatoxin B1, and aflatoxin B2 (100, 8.8, and 5.9%, respectively); a similar result was obtained for anti-AG2a antibodies reacting with AG2a, aflatoxin G1, and aflatoxin G2 (100, 2.5, and <1.0%, respectively). Binding of anti-AB2a and anti-AG2a antibodies to solid-phase conjugates of AB2a or AG2a exhibited similar analytical characteristics.
Primary Structure of a Short Toxin from the Venom of a Vietnamese Scorpion (Buthus sp.) by N. A. Khoang; B. B. Berezin; V. E. Piskarev; I. A. Yamskov; A. Kh. Musalyamov; Ts. A. Egorov (pp. 111-114).
The complete amino acid sequence of an important toxin (toxin 14) from the venom of a Vietnamese scorpion (Buthus occitanus sp.) has been determined, which includes 35 amino acid residues and three disulfide bridges (molecular weight, 3843 Da). The comparison of the sequence with known sequences of short scorpion toxins led to the conclusion that toxin 14 belongs to a novel group of toxins affecting the excitability of myelinated nerves.