Forgot your password?
New user?
New Window Opens on the Secret Life of Microbes: Scientists Develop First Microbial Profiles of Ecosystems
CAS announces the release of SciFinder Scholar for Mac OS X
Press Releases
Press Releases
| Check out our New Publishers' Select for Free Articles |
Applied Biochemistry and Microbiology (v.37, #3)
Chemical Features of Medicinal Plants (Review) by M. Ya. Lovkova; G. N. Buzuk; S. M. Sokolova; N. I. Kliment'eva (pp. 229-237).
Data on chemical composition related to the synthesis of physiologically active substances (alkaloids, terpenoids, glycosides, phenolic compounds, etc.) and to the accumulation of individual elements or groups of five to ten elements (e.g., Cr, Co, Mn, and Zn) in medicinal plants were reviewed. Chemical features of medicinal plants serve as an integral determinant of their species specificity and pharmacological properties and enable their wide use in medical practice. The relationship between the synthesis of physiologically active substances and accumulation of elements is mediated by several levels of molecular regulation.
Immunomodulatory Properties of 2-C-Methyl-D-Erythritol-2,4-Cyclopyrophosphate and the Search for Its New Derivatives by V. D. Potapov; S. F. Biketov; G. R. Demina; E. I. Lysak; G. M. Titareva; I. V. Bakhteeva; D. N. Ostrovsky (pp. 238-242).
A strong immunomodulatory effect of 2-C-Methyl-D-erythritol-2,4-cyclopyrophosphate (MEC) responsible for the survival of bacteria was shown on isolated macrophages and in experimental infections in mice (typhoid and tularemia). Derivatives of MEC were found by 1H-NMR spectroscopy under stress conditions in colorless mutants of the bacteria and isolated to be subsequently purified and used for modulation of the immune system of animals.
Effect of Inhibitors of Enzymatic DNA Methylation on the Formation of Reproductive Structures and Carotenoid Production in Neurospora crassa by M. S. Kritsky; S. Yu. Filippovich; T. P. Afanasieva; G. P. Bachurina; V. E. A. Russo (pp. 243-247).
The effect of inhibitors of DNA methylation on light-sensitive developmental stages of the filamentous fungus Neurospora crassawas studied. Under conditions of nitrogen starvation, when blue light induced protoperithecia development and inhibited conidia formation, 5-azacytidine (3–300 μM) inhibited protoperithecia formation and stimulated conidia formation (a 700-fold increase after light induction). After treatment of the mycelium with 5-azacytidine, the protoperithecia formation was accompanied by inversely proportional changes in the formation of conidia, both in the dark and after illumination. In the mycelium cultivated on the Vogel's medium, 5-azacytidine (up to 30 μM) and methotrexate (up to 3 μM) stimulated the light-induced carotenoid synthesis by 30%, whereas higher concentrations of these agents were toxic to carotenoid synthesis and growth.
Oxidation of Indole and Indole Derivatives Catalyzed by Nonheme Chloroperoxidases by V. N. Burd; R. Bantleon; K.-H. van Pee (pp. 248-250).
Indole, indolylacetic acid, and tryptophan were oxidized by chloroperoxidases isolated from strains of Streptomyces lividansand Pseudomonas pyrrocinia. Indigo (indoxyl), isatin, and anthranilic acid (intermediate products of oxidative degradation of indole and indole derivatives) were isolated from the reaction medium.
Study of the Lytic Activities of Actinomycetes Isolated from Different Soils in Georgia by P. G. Kudukhashvili; M. A. Gurielidze; D. T. Pataraya (pp. 251-252).
The lytic activities of 310 cultures from the Collection of Actinomycetes of the Institute of Biochemistry and Biotechnology, National Academy of Sciences of Georgia, were studied; 18% of these strains appeared capable of lysing yeast cell wall. The active producer of the enzyme was selected. This culture was isolated from chestnut soil in Gardabani raion (Central Georgia). Its cultural–morphological, biochemical, and antagonistic properties allowed the culture to be ascribed to the species Geodermatophilus obseurusLuedemann, 1968. The maximal lytic activity under submerged cultivation conditions, exceeding the activity of Actinomyces griseinusby twofold, was observed during the logarithmic growth phase.
Rugulosuvines A and B, Diketopiperazine Alkaloids of Penicillium rugulosumand Penicillium piscariumFungi by A. G. Kozlovsky; V. M. Adanin; H. M. Dahse; U. Grafe (pp. 253-256).
Two diketopiperazine alkaloids, rugulosuvines A and B (tryptophan and phenylalanine are their precursors), were isolated and purified from a culture liquid of Penicillium rugulosumVKM F-352 and Penicillium piscariumVKM F-325 fungi. Physical and physicochemical studies showed the absolute structure of rugulosuvine A. The absolute structure of rugulosuvine B was demonstrated to be identical to that of rugulosuvine A.
Dependence of the Activity of L-Amino Acid Oxidase in the Fungus Aspergillus nigerR-3 on the Source of Nitrogen in the Growth Medium by A. R. Papoyan; S. P. Oganesyan; M. A. Davtyan (pp. 257-259).
Various populations of peroxisomes in cells of Aspergillus nigerR-3 were formed under growth in media containing 0.5% glucose and various sources of nitrogen (1/4 of the optimal concentrations of (NH4)2SO4, L-alanine, and L-methionine). Different levels of L-amino acid oxidase activity were found in these populations of peroxisomes.
Isolation of Components of the Peptide Antibiotic Virginiamycin and Breeding of Their Producer, Streptomyces virginiae by V. I. Zvenigorodskii; B. V. Tyaglov; T. A. Voeikova (pp. 260-266).
A method for chromatographic separation and quantitative determination of individual components of the antibiotic virginiamycin, produced by microbiological synthesis (Streptomyces virginiaestrain 147), is described. The components, M1–2and S1–5, were isolated from fermentation broth and identified by HPTLC and HPLC (the results obtained using the two methods correlate well with each other). The conditions of culturing of the producer and the composition of nutritive media were optimized. Using UV irradiation as a mutagenic factor, the producer was selected for increased level of synthesis of the antibiotic; this was achieved by inducing mutations that impart resistance to virginiamycin and meta-fluorophenylalanine, an analog of phenylalanine.
Biosynthesis of Polyketide Antibiotics by Various StreptomycesSpecies that Produce Actinomycins by T. A. Alekhova; T. Y. Novozhilova (pp. 267-273).
A collection of actinomycin-producing Streptomycesstrains, their variants with different levels of antibiotic biosynthesis, and recombinant strains were screened in order to select new strains that produce polyketide antibiotics. Screening with the use of the cloned actgene encoding a component of actinorhodin polyketide synthase (PKS) multienzyme complex from Streptomyces coelicolorrevealed that many strains tested can synthesize polyketide antibiotics along with actinomycins. A relationship between the biosynthetic pathways of actinomycins and polyketides is discussed.
Microelement Preparations Obtained During the Processing of Natural Flint Affect the Physiology and Biochemistry of Bifidobacteria by G. I. Novik; N. I. Astapovich; A. A. Samartsev (pp. 274-281).
Microelement preparations obtained in the course of processing flint powder stimulate the biological activity of Bifidobacterium adolescentis94-BIM grown on complex and synthetic nutritive media. The composition of the microelement preparations differed in the content of cations and anions. Introduction of the preparations into cultures of physiologically active or anabiotic forms of bifidobacteria changed the parameters of exponential growth: compared to the controls, the cultures were characterized by an increased specific growth rate and a decreased generation time. In the presence of microelements, the development of populations of bifidobacteria was associated with a more pronounced accumulation of metabolic products (acetate, lactate, and ethanol). Introduction of microelement preparations increased the rate of synthesis of the extracellular proteinase (the maximum content of the enzyme was observed after 3 h, whereas control cultures attained this level only after 6 h).
The Respiratory Activity of Rhodococcus rhodochrousM8 Cells Producing Nitrile-Hydrolyzing Enzymes by S. M. Rogacheva; O. V. Ignatov (pp. 282-286).
The respiratory activity of Rhodococcus rhodochrousM8 cells containing nitrile hydratase and amidase was studied in the presence of nitriles and amides of carbonic acids. The culturing of cells with acrylonitrile and acrylamide yielding maximum respiratory activity was studied. The optimum conditions for measurements and maintenance of respiratory activity were found. Curves for the linear concentration dependence of cell respiratory activity on 0.01–0.5 mM acrylonitrile, 0.025–1.0 mM acetonitrile, and 0.01–0.1 mM acrylamide were plotted. The selectivity of cell respiratory activity for some substrates was analyzed.
The Structure and Characteristics of Glucomannans from Eremurus iaeand E. zangezuricus: Assignment of Acetyl Group Localization in Macromolecules by N. I. Smirnova; N. M. Mestechkina; V. D. Shcherbukhin (pp. 287-291).
Water-soluble glucomannans from roots of Eremurus iaeand E. zangezuricuswere studied. These polysaccharides were shown to contain 28.8, 69.0, and 2.2% (E. iae) and 22.6, 74.8, and 2.6% (E. zangezuricus) D-glucose, D-mannose and acetyl groups, respectively. Their IR spectra were identical and revealed the presence of 1,4-β-glycosidic bonds and ester carbonyl groups. 13C-NMR spectroscopy revealed both polysaccharides to be linear partially acetylated 1,4-β-D-glucomannans. Acetyl groups substituted C2- and C3-hydroxyls of mannopyranose residues. A comparison of 13C-NMR data and the results of correlation analysis suggested that acetyl groups can substitute no more than one OH-group in the mannopyranosyl residue. The estimated values of [α] D , [η], and molecular weights (MW) were –34.0°, 6.05 dl/g, and 265.5 kDa, respectively, for E. iaepolysaccharide, and –38.2°, 5.4 dl/g, and 233.5 kDa, respectively, for E. zangezuricuspolysaccharide. A correlation between the intrinsic viscosities of polysaccharides and their molecular weight determined by HPLC was revealed.
A Protein Hydrolysate Enzymatically Produced from the Industrial Waste of Processing Icelandic Scallop Chlamys islandica by V. A. Mukhin; V. Yu. Novikov; L. S. Ryzhikova (pp. 292-296).
Dry hydrolysate was prepared from protein-containing waste of Icelandic scallop processing by means of a proteinase complex from king crab hepatopancreas. The resulting product contains no less than 80% free amino acids and oligopeptides. Predominant are aspartic acid, leucine, isoleucine, arginine, and lysine, which account for more than 50% of the free amino acids. The potential of using the protein hydrolysate as a nutrient for microorganism cultivation is estimated. It is demonstrated that the hydrolysate can be used for growing test cultures.
Mineral Composition of Cultured Ginseng Cells by T. M. Sovetkina; T. K. Kalenik; V. P. Bulgakov; E. G. Yasnetskaya; Yu. N. Zhuravlev (pp. 297-300).
The contents of macroelements and microelements in ginseng roots and callus cultures was determined by atom absorption spectroscopy. Ginseng cells and tissues were shown to accumulate considerable amounts of microelements. The content of six of the eleven mineral components studied (K, Ca, Na, Mo, Mn, and Cr) in callus cultures was higher than that in roots of agricultural ginseng plants. We revealed good correlations between the contents of microelements (K, Ca, and Mg), as well as between the concentrations of macroelements (Mo, Li, Cu, and Cr), in ginseng cultures. The ability to accumulate elements varied between ginseng species, which was probably related to their genetic features. Our findings indicate that cultured ginseng cells hold much promise as a source of microelements.
Transformed Potato Plants Carrying the Gene of the Antifungal Peptide of Amaranthus caudatus by N. S. Lyapkova; N. A. Loskutova; A. N. Maisuryan; V. V. Mazin; N. P. Korableva; T. A. Platonova; E. P. Ladyzhenskaya; A. S. Evsyunina (pp. 301-305).
Potato plants (Solanum tuberosumL., var. Desire) were transformed with a pH22Kneo vector harboring the gene ac2, which encodes the fungicidal peptide (defensin) from the seed of amaranth (Amaranthus caudatusL.). The transformation involved cocultivation on a solid MS medium of potato stem explants (excised from aseptically grown plants) andAgrobacterium tumefaciens. The factors affecting in vitroregeneration of the explants and the transformation efficiency were optimized. Regenerated potato plants carrying the amaranth defensin gene were selected by two traits, growth and ability to form roots on a kanamycin-supplemented MS medium. The transgenic state was confirmed by PCR analysis of ac2in tissues of the kanamycin-resistant plants. The transgenic organisms thus obtained differed from the original plants in their patterns of Ambiol-induced growth and proton translocation across the plasma membrane of the tuber cells.
Effect of Arachidonic Acid on Potato Tubers during Storage by G. I. Chalenko; L. I. Il'inskaya; O. L. Ozeretskovskaya (pp. 306-309).
Potato (Solanum tuberosumL.) tubers were treated with various concentrations (10–9to 10–4M) of biogenic elicitor arachidonic acid during storage (from October to June). The data showed that the resistance-inducing concentration of arachidonic acid was 10–6M in autumn and 10–9M in spring. The possible causes of the change in the immunizing concentration of arachidonic acid during storage of potato tubers are discussed.
Lipids of Microorganisms of the Family Vibrionaceae, Causative Agents of Fish Diseases by V. V. Bogdan; L. P. Smirnov; V. S. Sidorov (pp. 310-313).
Lipid fractions and fatty acid compositions of microorganisms from the genera Aeromonas, Pseudomonas, and Vibrio(the family Vibrionaceae) that cause diseases of various fish species were studied. Motile aeromonads and vibrios displayed higher relative contents of membrane lipids and oleic acid and lower relative contents of storage lipids compared with nonmotile aeromonads and pseudomonads, which is connected with the activities of their movements. Nonmotile aeromonads and vibrios exhibited higher levels of polyunsaturated fatty acids and higher absolute phospholipid contents compared to motile aeromonads and pseudomonads. This is likely to be related to the host specificity of these bacteria and reflects the specific patterns of fatty acid compositions of the infected fish (salmonid and cyprinid) tissues.
Adaptive Changes in Fatty Acid Compositions of Whitefish Coregonus lavaretusL. Tissue Lipids Caused by Anthropogenic Factors by L. V. Toivonen; Z. A. Nefedova; V. S. Sidorov; Yu. N. Sharova (pp. 314-317).
Adaptive processes in the body of whitefish (Coregonus lavaretusL.) caused by anthropogenic effects on aquatic systems were studied. It was demonstrated that the content of fatty acid acyls correlated with the water pollution level. The role of a decrease in the content of arachidonic acid in fish reproduction under adverse conditions is discussed. It is underlined that the quantitative alterations in the gonad and liver fatty acid patterns are unidirectional. The compensatory character of the changes discovered is hypothesized.
Use of High-Dispersion Materials for Culturing and Obtaining Granular Agrobacterium radiobacterPreparations by I. K. Kurdish; L. V. Titova (pp. 318-321).
The effects of synthetic and natural high-dispersion materials on the growth of Agrobacterium radiobacterwere studied. Natural minerals montmorillonite and palygorskite (10 g/l nutrient medium) were more potent than high-dispersion silica and its modified forms in stimulating growth of Agrobacterium radiobacter. The interaction of Agrobacterium radiobacterwith clay minerals increased the survival rate of bacteria at supraoptimal temperatures. We elaborated a new granular bacterial preparation which enhanced the productivity of cucumbers by 12–15%.
The Effect of Soil Inoculation with Microbial Pesticide Destructors on Plant Growth and Development by T. O. Lisina; N. G. Garan'kina; Yu. V. Kruglov (pp. 322-326).
Soil inoculation with liquid cultures of Bacillus megaterium501 and Exophiala nigrumA-29 capable of degrading several organophosphorus pesticides accelerated the growth and development of experimental plants, the formation of their generative organs, and improved their productivity. This was particularly observed under stress plant growth conditions on phytotoxic peach substrates. The microorganisms inoculated can probably degrade the phytotoxins present in soils, thereby favoring plant development.
Effect of Thermolability of Milk Proteins on Ion Distribution in Skimmed Milk-Water-Salt, Two-Phase System by N. K. Genkina; G. I. Koltysheva (pp. 327-330).
Significant increases in concentrations of bivalent metals (Ca2+, Mg2+, and Cd2+) in the protein phase were observed after acidification (pH 4.7) of skimmed milk preheated at 95°C for 90 min. The increase was caused by denaturation of milk whey proteins and formation of protein–protein and protein–carbohydrate aggregates. Preheating did not influence the distribution of nitrate ions in the two-phase system.