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Applied Biochemistry and Microbiology (v.44, #4)
Nonheme iron proteins as an alternative system of antioxidant defense in the cells of strictly anaerobic microorganisms: A review by A. L. Brioukhanov (pp. 335-348).
Enzymatic systems accounting for the relative oxygen resistance of multiple strict anaerobes are reviewed, with emphasis on molecular-biological properties and action mechanisms of nonheme iron proteins (neelaredoxins, desulfoferrodoxins, and rubrerythrins). These unique proteins, which are widespread in anaerobes, comprise a system of antioxidant defense against toxic effects of oxygen and products of its incomplete reduction (an alternative to the classic antioxidant system involving superoxide dismutase and catalase). The role of the superoxide reductase-mediated elimination of endogenous superoxide radicals is discussed. This extremely efficient means of rapid superoxide radical detoxification underlies the preferred mechanism for maintaining the optimum balance between oxidized and reduced forms of some proteins in the cells of strict anaerobes.
Identification of catalytically active groups of wheat (Triticum aestivum) germ lipase by O. S. Korneeva; T. N. Popova; V. S. Kapranchikov; E. A. Motina (pp. 349-355).
The active site of wheat germ lipase was studied by the Dixon method and chemical modification. The profile of curve log V = f(pH), pK and ionization heat values, lipase photoinactivation, and lipase inactivation with diethylpyrocarbonate and dicyclohexylcarbodiimide led us to assume that the active site of the enzyme comprises the carboxylic group of aspartic or glutamic acid and the imidazole group of histidine. Apparently, the OH-group of serine plays a key role in catalysis: as a result of incubation for 1 h in the presence of phenylmethylsulfonyl fluoride, the enzyme activity decreased by more than 70%. It is shown that ethylenediamine tetraacetate is a noncompetitive inhibitor of lipase.
Isolation and biochemical characterization of δ-aminolevulinic acid dehydratase from Streptomyces yokosukanensis ATCC 25520 by M. Konuk; I. H. Ciğerci; Ş. Aksan; S. E. Korcan (pp. 356-360).
In this study, δ-aminolevulinic acid dehydratase (ALAD) from Streptomyces yokosukanensis ATCC 25520, producer of an unusual purine riboside antibiotic called nebularine, was purified and characterized. Purification procedures were involved with ammonium sulphate precipitation and gel filtration techniques by use of Sephacryl S-200. After gel filtration a 90.76-fold purification was obtained. The maximum enzymic activity was observed in the supernatant after 100% precipitation. According to the data obtained from the investigation, the enzyme was found to be a single polypeptide having a molecular mass around 34.8 kDa. This was determined by SDS-PAGE. Its optimal temperature was around 45° C, and optimal pH was found to be 8.0. Some heavy metals, Pb2+, Zn2+, Fe3+, Co2+, Mn2+, and Mg 2+, inhibited its activity between 20–51%, and Ni2+ increased its activity up to 15%. The text was submitted by the authors in English.
System of oligonucleotide primers for detection and amplification of the emoA gene encoding bacterial ethylenediaminetetraacetate monooxygenase by E. N. Kaparullina; D. N. Fedorov; N. V. Doronina; Yu. A. Trotsenko (pp. 361-365).
A system of primers was designed on the basis of analysis of nucleotide sequences of the emoAgene encoding ethylenediaminetetraacetate (EDTA) monooxygenase, which are deposited in GenBank. This system of primers makes it possible to obtain emoA gene fragments approximately 750 bp long for bacterial destructors of EDTA. Polymerase chain reaction (PCR) of total DNA isolated from enrichment and pure cultures showed that this system can be effectively used for detecting the emoAgene in representatives of Alpha- and Gammaproteobacteria. Partial sequences of emoA genes of bacteria of the genera Chelativorans and Stenotrophomonas, which are able to degrade this pollutant, have been sequenced and deposited in GenBank.
The thermophilic bacteria hydrolyzing agar: Characterization of thermostable agarase by G. E. Bannikova; S. A. Lopatin; V. P. Varlamov; B. B. Kuznetsov; I. V. Kozina; M. L. Miroshnichenko; N. A. Chernykh; T. P. Turova; E. A. Bonch-Osmolovskaya (pp. 366-371).
Three strains of anaerobic thermophilic bacteria capable of growing on agarose as a source of energy and carbon were isolated from hot springs near Lake Baikal (Barguzin National Park) and the caldera Uzon (Kamchatka). Cells of all the three strains were spore bacilli with peritrichous flagellation. These isolates grew at a temperature of 55–60°C and pH 6.5–7.0 and fermented a wide range of organic substrates. Analysis of the 16S rRNA sequences allowed us to ascribe the strains B5 and K14 to the genus Thermoanaerobacter and the strain K67 to the genus Caldoanaerobacter. According to the results of DNA-DNA hybridization, B5 was determined as belonging to the species Thermoanaerobacter wiegelii. Agarase was isolated by preparative PAGE and subsequent gel chromatography from the culture liquid of strain B5 grown on the medium containing 0.5% agarose and 0.3% galactose. The molecular weight of this enzyme amounted to 67 kDa and pI, to 4.2. The T. wiegelii B5 agarase was active in the pH range of 3.5 to 7.0 (optimum, 5.2) and temperature range of 50 to 80°C (optimum, 70°C). The preincubation of this enzyme at 90° C for 60 min did not reduce the agarase activity. This activity increased in the presence of metal ions; the maximal effect was observed in the presence of 5 mM Mg2+ and 25 mM Co2+.
Piezoquartz immunosensors for assessing the interactions between Yersinia enterocolitica lipopolysaccharides and antibodies to them by E. N. Kalmykova; E. S. Dergunova; T. N. Ermolaeva; R. P. Gorshkova; N. A. Komandrova (pp. 372-377).
The utility of a piezoquartz immunosensor coated with lipopolysaccharides (LPS) for the quantification of antibody specificities was demonstrated. Immunochemical reactions were monitored according to the changes in the weight of sensor bioreceptor layer with high sensitivity (detection limit, 1.3 μg/ml) and assay rate (10 min) without any additional labels. The capabilities of this sensor were demonstrated by the example of quantifying the cross-reactivity of blood serum antibodies with the LPS of Yersinia enterocolitica serotypes O:3, O:5, O:5.27, O:6.30, and O:6.31. The proposed approach is promising for clinical diagnostics of yersiniosis, an infectious intestinal disease.
Natural and recombinant luminescent microorganisms in biotoxicity testing of mineral waters by D. G. Deryabin; E. S. Aleshina (pp. 378-381).
We have developed methods of biotesting mineral waters involving use of natural or recombinant luminescent strains with elimination of the effect of degree of mineralization and pH. To overcome the adverse effect of high salt concentrations, disguising the action of chemical pollutants, a special method of mineral water sample preparation is proposed. In this method, the marine luminescent bacterium Photobacterium phosphoreum (Microbiosensor B-17 677f) is used as a test object. Samples to be analyzed are supplemented with NaCl depending on their natural degree of mineralization to adjust it to 30 g/l. Another approach, more universal and efficient, involves pH adjustment in the samples to 7.5. This value is suitable for application of both Microbiosensor B-17 677f and the recombinant Escherichia coli strain harboring the cloned lux operon of P. leiognathi (Ecolum-9). It has been shown that this treatment, retaining the natural luminescence level of the bacterial biosensors, allows bioluminescent detection of exogenous pollutants added to the samples, including benzene and Cr(VI).
Degradation of hydrocarbons and their derivatives by a microbial association on the base of Canadian pondweed by Yu. A. Tumaikina; O. V. Turkovskaya; V. V. Ignatov (pp. 382-388).
The degrading action of an aquatic plant-microbial association on the base of Canadian pondweed (Elodea canadensis) and its components (sterilized plant and two periphytonic strains, Pseudomonas fluorescens El-2.1 and Brevundimonas diminuta El-3.1) on crude oil, the water-soluble crude oil fraction, and individual test compounds (phenol, toluene, benzene, decalin, and naphthalene) was studied. It was found that the native association had a wider range and higher degree of degrading activity than individual species. Bacterial strains were significantly more active only towards naphthalene. The ability of the sterilized plant to degrade crude oil and phenol was no less than that of microorganisms and much more for toluene. Enzymatic activity towards the pollutants studied was found in E. canadensis exudates and buffer extracts of its cells.
Efficiencies of introduction of an oil-oxidizing Dietzia maris strain and stimulation of natural microbial communities in remediation of polluted soil by E. V. Pleshakova; E. V. Dubrovskaya; O. V. Turkovskaya (pp. 389-395).
Two approaches to bioremediation of oil-polluted soils are compared: use of active degrader strain Dietzia maris AM3 and stimulation of natural microflora. Introduction of D. maris AM3 to soil freshly polluted with oil accelerated its remediation twofold within the first month in comparison with the stimulation. After three months, the purification degrees were approximately equal. By the end of bioremediation, the soil with the introduced strain had higher dehydrogenase and catalase activities. In soil with aged pollution, introduced strain D. maris AM3 did not affect the rate of oil product degradation, and no significant differences between the two bioremediation methods were detected in purification degree and biological activity of soil after three months.
Effect of nitric oxide and other nitrogen compounds on the adhesion and penetration of nodule bacteria into root tissues and on growth of etiolated pea seedlings by A. K. Glyan’ko; N. B. Mitanova; G. G. Vasil’eva (pp. 396-399).
The action of sodium nitroprusside, a nitric oxide donor, and other nitrogen compounds (KNO3, KNO2, and (NH4)2SO4) on adhesion and penetration of nodule bacteria into root tissues of etiolated pea seedlings was studied. Only nitroprusside displayed a clearly negative effect on rhizobium adhesion and penetration and seedling growth. This effect was not observed with other nitrogen compounds even at high (20 mM) concentrations. Hemoglobin attenuated the negative effect of nitroprusside on bacteria and seedlings. The results are discussed in the context of the role of nitric oxide in the life of plants and nodule bacteria.
The effect of Azotobacter vinelandii on plant seed germination and adhesion of these bacteria to cucumber roots by I. K. Kurdish; Z. T. Bega; A. S. Gordienko; D. I. Dyrenko (pp. 400-404).
Bacterization of seeds of several plant species with Azotobacter vinelandii suspension stimulates their germination to different degrees. This demonstrates that seeds of different species display different sensitivity to the biologically active substances accumulating in the culture liquid of these bacteria. The adhesion patterns of these bacteria to cucumber roots were studied. The maximal number of cells adhered to the root surface at the phase of culture logarithmic growth (24 h), when they were motile. The loss of motility in the stationary growth phase (72 h) decreased the number of cells adhered to roots by 80%.
Coriolus hirsutus laccase effect on atrazine adsorption and desorption by different types of soil by V. N. Davidchik; N. A. Kulikova; L. I. Golubeva; E. V. Stepanova; O. V. Koroleva (pp. 405-410).
Study of adsorption-desorption behavior of herbicide atrazine in soils of different geographical zones in the presence of Coriolus hirsutus laccase was performed. Laccase was shown to significantly increase adsorption coefficient and to facilitate irreversible adsorption of atrazine to soil. Supposably, laccase catalyzes oxidative binding of atrazine to soil.
Effects of conditions for obtaining sporangiospores of the inoculum on the morphology and productivity of the fungus Mucor circinelloides var. lusitanicus 12 M, a producer of γ-linolenic acid by N. S. Funtikova; I. S. Mysyakina (pp. 411-415).
Effects of the lipid composition of sporangiospores of the fungus Mucor circinelloides var. lusitanicus 12 M, obtained within diverse time frames using distinct nutrient media, on the morphology of the fungus in submerged cultures, the yield of the biomass, and its content of g-linolenic acid have been studied. The levels of base phospholipids and individual fractions of neutral lipids in sporangiospores correlated with the character of their germination. The spores that were characterized by a high rate of germination and gave rise to a well-developed mycelium contained more phosphatidylcholine and phosphatidylserine, but the level of diacylglycerols was low. The increase in diacylglycerols, free fatty acids, and sterols in lipids of sporangiospores of the inoculate was associated with deterioration in mycelium development, dimorphism, and a decreasing yield of the biomass of the fungus.
Genetic aspects of the interrelation between alkaloids and chemical elements in Atropa belladonna L. and Glaucium flavum Crantz. Plants by M. Ya. Lovkova; G. N. Buzuk; S. M. Sokolova (pp. 416-419).
The variability of the contents of tropane and isoquinoline alkaloids, ashes, Na, K, Ca, Mg, Fe, Mn, Cu, Zn, Co, Mo, Cr, Al, Ba, V, Ni, Sr, Cd, Pb, J, and Ag was studied in individual plants of the industrial population of belladonna (Atropa belladonna L.) and yellow horned poppy (Glaucium flavum Crantz.). Numerous linear and nonlinear correlations of isoquinoline and tropane alkaloids with ashes and mineral elements were revealed by means of correlation and regression analyses. Alkaline earth elements (especially Sr and Ba) were shown to have a major role in the regulation of tropane alkaloid accumulation in belladonna leaves. K and Ni were of particular importance in the aerial part of yellow horned poppy. These elements at the suboptimal concentrations were most favorable for isoquinoline alkaloid accumulation in yellow horned poppy. Analytical mathematical models were derived for the regulation of alkaloid metabolism in test plants by some mineral elements (Ba, Mg, Al, Sr, Ni, Mn, and K). Our results indicate that the interrelation between alkaloids and elements in these plants is genetically determined.
Calixarenes: Influence on energy exchange of plant tissues by Yu. N. Valitova; L. Kh. Gordon; I. S. Ryzhkina; L. A. Kudryavtseva (pp. 420-424).
The distinctive features of the influence of synthetic compounds of a new class, calixarenes, on the energy exchange of the plant tissues and on the ionic permeability of the plant membranes were investigated. Calixarenes of the different chemical structure were shown to sufficiently influence the oxygen consumption by wheat roots, pH of the incubation mixture, and the potassium ions release. Aminomethylated calyx[4]resorcinaren showed the highest effect. The influence of these compounds on the wheat roots was pH dependent.
Effect of melafen on the function of endoplasmic reticulum and plasmalemmal H+-atpase in the regulation of growth processes in potato tubers by T. A. Platonova; E. P. Ladyzhenskaya; A. S. Evsyunina; N. F. Lagutina; N. P. Korableva (pp. 425-431).
The mechanism of the stimulatory effect of melafen on potato tuber sprouting was studied. The treatment with 10−8 M melafen intensified division and stretching and activated granular endoplasmic reticulum of apical meristem cells. An increase in the activity of membrane-bound H+-ATPase in the plasmalemma of parenchymal cells of melafen-treated potato tubers and enhancement of passive proton permeability of the plasmalemma was observed. In vitro studies showed that melafen at concentrations of 10−5−10−12 M stimulated the activity of plasmalemmal H+-ATPase in a concentration-dependent manner.
Protein markers for identification of different species and varieties of cotton by I. Zh. Kurbanbaev; D. Yu. Ataev; Sh. Yunuskhanov (pp. 432-437).
Reference electrophoretic spectra that allow compiling electrophoretic formulas of certain cotton species and varieties were obtained on the basis of analysis of the electrophoretic spectrum of water-soluble and barely soluble proteins of seeds of diploid cotton species of genomic group A (Gossypium arboreum var. indicum, G. arboreum ssp. obtusifolum, G. herbaceum ssp. africanum, and G. herbaceum Harga), group C (G. australe, G. bickii, G. nelsone, and G. sturtianum), group D (G. davidsonii, G. harknessii, G. klotzschianum, G. raimondii, G. thurberi, and G. trilobum), and amphidiploid species of group AD (G. mustelinum, G. hirsutum ssp. palmeri, G. tricuspidatum Bagota, G. tricuspidatum Mari Galanta, G. barbadense L., and G. hirsutum L.)
Antioxidant properties of essential oils from lemon, grapefruit, coriander, clove, and their mixtures by T. A. Misharina; A. L. Samusenko (pp. 438-442).
Antioxidant properties of individual essential oils from lemon (Citrus limon L.), pink grapefruit (Citrus paradisi L.), coriander (Coriandrum sativum L.), and clove (Caryophyllus aromaticus L.) buds and their mixtures were studied by capillary gas-liquid chromatography. Antioxidant activity was assessed by oxidation of the aliphatic aldehyde hexanal to the carboxylic acid. The lowest and highest antioxidant activities were exhibited by grapefruit and clove bud essential oils, respectively. Mixtures containing clove bud essential oil also strongly inhibited oxidation of hexanal. Changes in the composition of essential oils and their mixtures in the course of long-term storage in the light were studied. The stability of components of lemon and coriander essential oils in mixtures increased compared to individual essential oils.
Unsaturated fatty acids and aldehydes during treatment of oak wood by A. F. Pisarnitskii; K. A. Askenderov (pp. 443-445).
The use of considerable amounts of ground oak to accelerate maturation of strong drinks was accompanied by the appearance of an undesirable taste due to the presence of unsaturated aldehydes (2-nonenal and 2,4-nonadienal). The greater the degree of wood grinding, the higher was the content of C18-unsaturated acids and C9-aldehydes. Wood heating was accompanied by a decrease in the content of C18-acids, but had no effect on the amount of aldehydes. An undesirable taste decreased during the maintenance of alcoholic tinctures in 70% ethyl alcohol for 6 months. It was related to the formation of acetals and ethoxy and hydroxy derivatives of unsaturated aldehydes.