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New Window Opens on the Secret Life of Microbes: Scientists Develop First Microbial Profiles of Ecosystems
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Applied Biochemistry and Microbiology (v.41, #4)
Calcium as a Regulator of Intracellular Processes in Actinomycetes: A Review by V. N. Danilenko; V. A. Mironov; S. M. Elizarov (pp. 319-329).
Data on the effects of calcium ions (Ca2+) on processes of morphological and physiological differentiation in cultures of actinomycetes have been reviewed, with emphasis on representatives of the genus Strepomyces. Evidence accumulated thus far regarding the regulatory role of serine-threonine protein kinases in the differentiation and the possible involvement of Ca2+-dependent protein kinases in secondary metabolism (including antibiotic biosynthesis) are analyzed. The possibility that regulatory elements of apoptosis (including Ca2+-dependent) function in actinomycetes is discussed. A hypothesis is advanced, according to which determinants of antibiotic resistance play a key role in the network of signal transduction systems of actinomycetes.
Inhibition of Peroxidase-Catalyzed Oxidation of Chromogenic Substrates by Propyl Gallate and Its Polydisulfide by I. V. Naumchik; E. I. Karasyova; D. I. Metelitza (pp. 330-335).
Peroxidase-catalyzed oxidation of 2,2′-azino-di-(3-ethyl-2,3-dihydrobenzthiazoline-6-sulfonate) (ABTS) was competitively inhibited by propyl gallate (PG) and its polydisulfide (PGPDS) at 20° C in 0.015 M phosphate-citrate buffer (pH 6.0). Under these conditions, the values of the inhibition constant (K i ) were equal to 62 and 5.6 μM, respectively, for PG and PGPDS. The stoichiometric inhibition factor (f; the number of radicals extinguished per molecule of an inhibitor) equaled 2.0 and 14.7, respectively, for PG and PGPDS. Peroxidase-catalyzed oxidation of o-phenylenediamine was barely affected by PG or PGPDS. PGPDS may be used as a stop-reagent of peroxidase-catalyzed ABTS oxidation, whereas PG may serve as a calibrating inhibitor in test systems for measurement of total antioxidant activity (in human biological fluids, natural preparations, juices, wines, and other objects).
Polymerization of Horseradish Peroxidase in the Presence of Inorganic Adsorbents by A. N. Eryomin; M. V. Makarenko; L. P. Budnikova (pp. 336-343).
Efficiencies of binding between horseradish peroxidase (HRP) and its polymers (HRPp) with inorganic adsorbents (precipitated and coprecipitated) were studied. In aqueous solutions, HRP efficiently adsorbed on aluminum oxide and the coprecipitated sorbent (composed of calcium orthophosphate, magnesium hydroxide, and aluminum hydroxide). HRP readily bound to zinc hydroxide but not to aluminum hydroxide in 25.0 mM bicarbonate buffer (pH 9.0). Several variants of HRP polymerization and HRPp modification with diamines in the presence of Al2O3 and Zn(OH)2 were compared. Synthesis of HRPp according to the scheme comprising HRP activation in solution followed by its polymerization in the presence of Zn(OH)2 appeared the most efficient. HRP and HRPp bound to Zn(OH)2 displayed a high catalytic activity in the presence of high H2O2 concentrations.
Proteinase Inhibitors as Antistress Proteins in Higher Plants by Ya. E. Dunaevskii; T. A. Tsybina; G. A. Belyakova; V. I. Domash; T. P. Sharpio; S. A. Zabreiko; M. A. Belozerskii (pp. 344-348).
Physicochemical and functional characteristics of plant protein proteinase inhibitors as antistress biopolymers were studied to determine the mechanisms for plant resistance to phytopathogens and to obtain disease-resistant cereal and leguminous cultures. The activity of trypsin, chymotrypsin, and subtilisin inhibitors varied in monocotyledonous and dicotyledonous cultures. Study varieties of leguminous and cereal cultures were shown to contain endogenous inhibitors specific to proteinases of phytopathogenic fungi Fusarium, Colletotrichum, Helminthosporium, and Botrytis. These inhibitors were characterized by species specificity and variety specificity. Protease inhibitors from buckwheat seeds inhibited proteases of fungal pathogens and suppressed germination of spores and growth of the fungal mycelium. Our results suggest that proteinaceous inhibitors of proteinases are involved in the protective reaction of plants under stress conditions.
Purification of Bovine Milk Lactoperoxidase and Investigation of Antibacterial Properties at Different Thiocyanate Mediated by M. T. Uguz; H. Ozdemir (pp. 349-353).
Bovine lactoperoxidase (LPO) was purified with amberlite CG 50 H+ resin, CM sephadex C-50 ion-exchange chromatography, and sephadex G-100 gel filtration chromatography from skim milk. The activity of lactoperoxidase was measured by using 2.2-azino-bis(3-ethylbenzthiazoline-6 sulfonic acid) diammonium salt (ABTS) as a choromogenic substrate at pH 6.0. Purification degree for the purified enzyme was controlled with SDS-PAGE and R z value (A 412/A 280). R z value for the purified LPO was 0.8. K m value at pH 6.0 at 20° C for the LPO was 0.20 mM. V max value was 7.87 μmol/ml min at pH 6.0 at 20°C. Bovine LPO showed high antibacterial activity in 100 mM thiocyanate -100 mM H2O2 medium for some pathogenic bacteria, such as Aeromonas hydrophila ATCC 7966, Micrococcus luteus LA 2971, Mycobacterium smegmatis RUT, Bacillus subtilis IMG 22, Pseudomonas pyocyanea, Bacillus subtilis var. niger ATCC 10, Pseudomonas aeruginosa ATCC 27853, Enterococcus faecalis ATCC 15753, Bacillus brevis FMC3, Klebsiella pneumoniae FMC 5, Corynebacterium xerosis UC 9165, Bacillus cereus EU, Bacillus megaterium NRS, Yersinia enterocolytica, Listeria monocytogenes scoot A, Bacillus megaterium EU, Bacillus megaterium DSM32, Klebsiella oxytocica, Staphylococcus aerogenes, Streptococcus faecalis, Mycobacterium smegmatis CCM 2067 and compared with well known antibacterial substances such as penicilline, ampicilline, amoxicillin-clavulanate and ceftriaxon. The LPO-100 mM thiocyanate-100 mM H2O2 system was purposed as an effective agent against many of the diseases causing organisms in human and animals.
Metabolites of Marine Organisms as Regulators of O-Glycosylhydrolases by N. S. Verigina; Yu. V. Burtseva; S. P. Ermakova; V. V. Sova; M. V. Pivkin; T. N. Zvyagintseva (pp. 354-360).
The ability of metabolites contained in culture liquid of 62 strains of marine fungi to affect the activity of two digestive enzymes of marine mollusks—endo-1,3-β-D-glucanase of Spisula sachalinensis and β-D-glucosidase of Littorina kurila—was studied. It was found that 66 and 71% of specimens activated, 18 and 7% inhibited, and 16 and 22% did not affect the activity of endo-1,3-β-D-glucanase and β-D-glucosidase, respectively. It is demonstrated that the metabolites of brown algae and marine sponges can be used for a targeted regulation of enzyme biosynthesis by marine fungi. The protein inhibitor of endo-1,3-β -D-glucanases isolated from the brown alga Laminaria cichorioides blocked the biosynthesis of almost all O-glycosylhydrolases in five strains of marine fungi studied. The presence in culture medium of halistanol sulfate from the marine sponge of the family Halichondriidae either did not affect or activated the biosynthesis of enzymes involved in carbohydrate metabolism by marine fungi.
Optimizing the Conditions of Dextran Synthesis by the Bacterium Leuconostoc mesenteroides Grown in a Molasses-Containing Medium by T. A. Vedyashkina; V. V. Revin; I. N. Gogotov (pp. 361-364).
Maximal dextran production (54–55 g/l) by the bacterium Leuconostoc mesenteroides strain V-2317D was observed in molasses-containing media in the presence of 17.5% glucose at pHinit 6.75. The beginning of dextran production depended on the amount of inoculate; maximum yield was observed at a shaker rate of 200 rpm. The dextran produced by L. mesenteroides grown in the molasses-containing medium was representative of three fractions differing in molecular weight and composition: the high-(∼54.5%), medium- (∼ 27.9%), and low-molecular-weight (∼2.85%) fractions.
Structural Characteristics and Biological Properties of Pseudomonas fluorescens Lipopolysaccharides by S. N. Veremeichenko; M. A. Vodyanik; G. M. Zdorovenko (pp. 365-371).
The structure and biological properties of lipopolysaccharides (LPSs) from strains IMB 4125 (=ATCC 13525) and IMB 7769 of the bacterium Pseudomonas fluorescens (biovar I) were studied in vitro. LPSs were similar in the composition of lipid A and the core lipid but differed in the structure of O-specific polysaccharide chains, which was corroborated by the absence of serological relationships between them. The toxicity (LD50) of LPSs of P. fluorescens with respect to D-glucosamine-sensitized mice was 40–50 times lower than the toxicity of the classic endotoxins, LPSs of E. coli. The LPSs studied stimulated the production of tumor necrosis factor (TNF) and nitric oxide (NO) by mouse peritoneal macrophages. The rates of TNF and NO synthesis induced by the LPSs of interest were eight to nine and three to five times lower, respectively, than the corresponding parameters of the control LPSs of E. coli 055:B5 and 026:B6._Additionally, LPS preparations of the P. fluorescens strains induced TNF synthesis by monocytes of human whole-blood preparations. Certain differences in biological properties of these strains have been revealed, which could be due to the characteristic features of LPS structure and composition in different cultures.
Anaerobic Microbial Associations Degrading Aminoaromatic Acids by I. B. Kotova; O. V. Savel’eva; A. T. D’yakonova; V. I. Sklyar; S. V. Kalyuzhnyi; A. Stams; A. I. Netrusov (pp. 372-376).
Anaerobic microbial associations have been isolated that degrade aminoaromatic acids to methane and carbon dioxide at high rates. Significant differences between the morphological, cytological, and physiological traits of cultures isolated from samples of adapted and unadapted sludge are shown. The effects of cultivation temperature, illumination, and presence of mineral nitrogen and bicarbonate in the medium upon adaptation of enrichment cultures to substrates and subsequent behavior of the anaerobic associations have been studied. Intermediate and final products of degradation of aminoaromatic compounds and the sequence of their formation in the cultures have been determined. We have also studied the effects of exogenous electron acceptors and additional carbon sources on the degradation of aminoaromatic compounds.
Determination of Minimal Concentrations of Biocorrosion Inhibitors by a Bioluminescence Method by E. N. Efremenko; R. E. Azizov; T. A. Makhlis; V. M. Abbasov; S. D. Varfolomeev (pp. 377-381).
By using a bioluminescence ATP assay, we have determined the minimal concentrations of some biocorrosion inhibitors (Kathon, Khazar, VFIKS-82, Nitro-1, Caspii-2, and Caspii-4) suppressing most common microbial corrosion inducers: Desulfovibrio desulfuricans, Desulfovibrio vulgaris, Pseudomonas putida, Pseudomonas fluorescens, and Acidithiobacillus ferrooxidans. The cell titers determined by the bioluminescence method, including not only fissiparous cells but also their dormant living counterparts, are two-to sixfold greater than the values determined microbiologically. It is shown that the bioluminescence method can be applied to determination of cell titers in samples of oil-field waters in the presence of iron ions (up to 260 mM) and iron sulfide (to 186 mg/l) and in the absence or presence of biocidal corrosion inhibitors.
Monitoring of Microbial Degraders in Manned Space Stations by T. A. Alekhova; A. A. Aleksandrova; T. Yu. Novozhilova; L. V. Lysak; N. A. Zagustina; A. M. Bezborodov (pp. 382-389).
Samples of microorganisms from the surface of constructions of Mir Space Station (Mir SS) were taken and examined after 13 years of operation. The following microorganisms were isolated and identified: 12 fungal species belonging to the genera Penicillium, Aspergillus, Cladosporium, and Aureobasidium; 3 yeast species belonging to the genera Debaryomyces, Candida, and Rhodotorula; and 4 bacterial species belonging to the genera Bacillus, Myxococcus, and Rhodococcus. The predominant species in all samples was Penicillium chrisogenum. It was shown that the fungi isolated could damage polymers and induce corrosion of aluminum-magnesium alloys. We commenced a study of microbial degraders on constructions of the Russian section of the International Space Station (RS ISS). Twenty-six species of fungi, bacteria, yeasts, and actinomycetes, known as active biodegraders, were identified in three sample sets taken at intervals. We founded a collection of microorganisms surviving throughout space flights. This collection can be used to test spacecraft production materials, in order to determine their resistance to biodegradation.
Extracellular Proteolytic Enzymes of Azospirillum brasilense Strain Sp7 and Regulation of Their Activity by a Homologous Lectin by M. P. Chernyshova; S. A. Alen’kina; V. E. Nikitina; V. V. Ignatov (pp. 390-393).
It was found that Azospirillum brasilense strain Sp7 is able to produce extracellular proteolytic enzymes. The enzymes were active within a broad range of pH values, with two peaks of activity being located in the acid and alkaline pH areas; required calcium ions; and exhibited substrate specificity with respect to azogelatin. Zymography allowed at least four proteolytic enzymes with molecular weights of 32, 45, 52, and 174 kDa to be detected in A. brasilense Sp7 culture liquid. It was shown that the lectin from A. brasilense Sp7 can inhibit proteolytic enzymes.
Lipid Composition of Cells of Heterothallic Strains in the Developmental Cycle of Blakeslea trispora by V. M. Tereshina; A. S. Memorskaya; E. P. Feofilova (pp. 394-398).
Lipid compositions in mycelium and spores of Blakeslea trispora heterothallic strains were studied. Distinctions between the strains in the ability to synthesize linolenic acid and in optimal growth temperature were demonstrated. The (−) strain grew at a higher temperature and was unable to synthesize linolenic acid, whereas the (+) strain accumulated this acid up to 20% of total fatty acids. The distinctions between the strains remained at different developmental stages (mycelium and spores). A higher thermotolerance of the (−) strain correlated with a high sterol content, which is typical of thermophilic fungi. The lipid compositions of heterothallic strains studied differed in lipid content, their fractional composition, the degree of unsaturation, and carotenoid composition.
Immobilized Yeast Membranes as Biocatalysts for Sucrose Inversion by G. A. Kovalenko; L. V. Perminova; G. V. Plaksin; O. V. Komova; T. V. Chuenko; N. A. Rudina (pp. 399-403).
Yeast membranes were obtained by autolysis of various strains with relatively high invertase activity. Heterogeneous biocatalysts for sucrose inversion were made of the yeast membranes and granulated carbon-containing supports made of common natural materials: expanded clay aggregate (ECA), sapropel, and lignin. The properties of these biocatalysts were studied. It was shown that the biocatalyst activity and stability of the immobilized yeast membranes increased with reference to the initial ECA, independent of the morphology of the carbon layer synthesized on the support surface. Heterogeneous biocatalysts prepared by adsorption of yeast membranes on sapropel had the greatest activity and stability, whereas lignin-based biocatalysts were relatively unstable.
Sterols of Mulberry Leaves and Small Leaf Curl Disease by N. E. Zambakhidze; K. V. Sulaberidze; V. V. Mzhavanadze; G. Ch. Tsiklauri (pp. 404-406).
Free and bound sterols of leaves of five mulberry cultivars differing in their susceptibility to small leaf curl disease have been studied. The total content of sterols in all samples is similar and is not correlated with the resistance of the cultivars. The qualitative composition of particular sterols is also identical. They are represented by cholesterol, campesterol, stigmasterol, sitosterol, and two 4α-methylsterols. The leaves of the most sensitive cultivar are characterized by high cholesterol content. The ratio sitosterol : stigmasterol decreased in proportion to the resistance level of a cultivar.
Sorption of Components from a Mixture of Essential Oils by Cryotextured Cornstarches by M. B. Terenina; T. A. Misharina (pp. 407-412).
Sorption by cryotextured cornstarches of components of the aqueous phase of a mixture of essential oils was studied by capillary gas chromatography. The amount of cryotexture-sorbed substances depended linearly on their concentration in the initial gel. The sorption of components from the mixture by starch polysaccharides was mainly associated with hydrophobic cooperative interactions, which resulted in the formation of supramolecular structures and inclusion complexes. The structure of the compounds was a major factor determining the degree of sorption. Sorption of monoterpene hydrocarbons was the most pronounced. We revealed a synergistic increase in the degree of sorption from the mixture as compared to binding of individual compounds.