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Applied Biochemistry and Microbiology (v.46, #1)
Extremophilic microorganisms: Biochemical adaptation and biotechnological application (review) by E. V. Morozkina; E. S. Slutskaya; T. V. Fedorova; T. I. Tugay; L. I. Golubeva; O. V. Koroleva (pp. 1-14).
In this review, we analyzed modern data on the biochemical adaptation of microorganisms to living under extreme conditions. Special attention is given to analysis of adaptation responses of microorganisms under exposure to increased radiation at molecular and cellular levels. Data on the practical use of extremophiles as well as extremoenzymes, biologically active compounds, biopolymers, etc., synthesized by them are systematized.
Reactive oxygen and nitrogen species in legume-rhizobial symbiosis: A review by A. K. Glyan’ko; G. G. Vasil’eva (pp. 15-22).
Published data on the role of reactive oxygen and nitrogen species (ROS and RNS, respectively) in the formation and functioning of the legume-rhizobial symbiosis are summarized. It is assumed that ROS and RNS fulfill a double function in the legume-rhizobial symbiosis by triggering the mechanisms enabling symbiosis formation and the mechanisms preventing the development of symbiotic structures (i.e., the defensive responses). A hypothetic scheme illustrating the involvement of ROS and RNS in the formation of legume-rhizobial symbiosis is proposed.
Effect of the structure of the brassinosteroid side chain on monooxygenase activity of liver microsomes by A. G. Sysa; P. A. Kiselev; V. N. Zhabinskii; V. A. Khripach (pp. 23-27).
Possible pathways by which brassinosteroids affect the monooxygenase enzymatic system of mammalian liver microsomes, which is involved in the transformation of a broad spectrum of xenobiotics, were studied. The role of the structure of the side chain of brassinosteroids in the regulation of monooxygenase activity was studied using two natural compounds (24-epibrassinolide and 28-homobrassinolide) and two synthetic analogues, (22S, 23S-dihydroxy) stereoisomers. The results of this study show that brassinosteroids can directly influence the functioning of the microsomal enzymatic system. It was found that the degree of this influence depends on the side chain structure. This suggests the possibility of targeted modification of natural compounds to ensure the desired physiological effects.
Characteristics of the response of natural and recombinant luminescent microorganisms in the presence of Fe2+ ions by D. G. Deryabin; I. F. Karimov (pp. 28-32).
It was found that divalent iron ions have alternative effects on the bioluminescence of the natural marine microorganism Photobacterium phosphoreum and the recombinant Escherichia coli strain with a cloned lux operon of P. leiognathi. In the presence of 0.25–5.0 mM FeSO4, the bioluminescence intensity of the former and the latter increased and decreased, respectively. To establish the causes of these differences, we studied the characteristics of the fatty acid composition of the compared microorganisms. The fatty acid profile of E. coli was characterized by a high proportion of unsaturated 11-octadecenoic (vaccenic) acid. A study of this acid in a cell-free enzyme system used for bioluminescence generation showed that it is a potent inhibitor of bacterial bioluminescence. It was found that such effects are enhanced if 11-octadecenoid acid is preincubated with Fe2+.
Growth and bioluminescence of luminous bacteria under the action of aflatoxin B1 before and after its treatment with nanodiamonds by O. A. Mogilnaya; A. P. Puzyr’; V. S. Bondar’ (pp. 33-37).
The effect of aflatoxin B1 on growth and luminescence of marine luminous bacteria P. phosphoreum and recombinant E. coli Z905 cells was investigated. The bidirectional effect of aflatoxin B1 on the studied bacterial species was detected—an inhibition of luminescence in P. phosphoreum and its stimulation in E. coli. It was shown that aflatoxin B1 influences the cell luminescence in the freshly grown cultures and bacteria restored after lyophilization. It was detected that the effect of aflatoxin B1 was graded after interaction with the modified nanodiamond (MND) of detonation synthesis. After mycotoxin’s treatment with MND, it does not cause significant changes in bacterial luminescence. The possibilities for the use of P. phosphoreum and E. coli bacteria in the bioluminescent monitoring of aflatoxin B1 and the use of MND for mycotoxin deactivation are discussed.
Rhizosphere bacteria Pseudomonas aureofaciens and Pseudomonas chlororaphis oxidizing naphthalene in the presence of arsenic by O. I. Sizova; V. V. Kochetkov; A. M. Boronin (pp. 38-43).
Rhizosphere strains of P. aureofaciens BS1393(pBS216, pKS1) and P. chlororaphis PCL1391(pBS216, pKS1), exhibiting the ability to stimulate the growth of plants and protect them from phytopathogens, have been obtained. In these strains, plasmid pBS216 ensures naphthalene degradation and plasmid pKS1 confers resistance to arsenic. In the presence of arsenic and naphthalene, the number of living cells and the growth rate of the arsenic-resistant strains were higher than those of the arsenic-sensitive strains BS1393(pBS216) and PCL1391(pBS216). During the cultivation of the resistant strains, arsenic had no inhibitory effect on the activity of the key enzymes of naphthalene biodegradation, except for catechol-2,3-dioxygenase. In a model system containing plant-microbial associations, strains BS1393(pBS216, pKS1) and PCL1391(pBS216, pKS1) degraded as much as 97% of added naphthalene in the presence of arsenic.
The production of auxins by the endophytic bacteria of winter rye by O. V. Merzaeva; I. G. Shirokikh (pp. 44-50).
The ability of the actinomycetes and coryneform bacteria isolated from the root tissues of winter rye to produce auxin in a liquid culture was studied. The isolates of coryneform bacteria produced indolyl-3-acetic acid (IAA) into the medium in the amount of 9.0–95.0 μg/ml and the isolates of actinomycetes in the amount of 39.5–83.0 μg/ml. The maximal IAA accumulation in culture liquid of actinomycetes coincided, in general, with the beginning of the stationary growth phase. The dependences of IAA synthesis by actino-mycetes on the composition and pH of nutrient medium, tryptophan concentration, and aeration conditions were determined. Biological activity of the bacterial IAA was assessed. Treatment of winter rye seeds with coryneform auxin-producing bacteria increased the germination capacity and enhanced an intensive seedling growth in vitro.
Chemotactic and adhesive properties of Azotobacter vinelandii and Bacillus subtilis by I. K. Kurdish; N. V. Chuiko; Z. T. Bega (pp. 51-56).
The effects of some factors on the chemotaxis of Azotobacter vinelandii IMV V-7076 and Bacillus subtilis IMV V-7023 and on their adhesion to cucumber roots have been studied. Glucose chemotaxis and adhesion to roots reach peak values in pH ranges characteristic of each strain. These ranges are 7.0–8.0 for A. vinelandii IMV V-7076 and 6.0–7.0 for B. subtilis IMV V-7023. The adhesion values of each species decrease significantly in their mixed suspension. The interaction of each of the strains with the clay mineral montmorillonite improves their adhesion to cucumber roots. The clay mineral palygorskite improves the adhesion of A. vinelandii but reduces that of B. subtilis.
Effects of bovine milk lactoperoxidase system on some bacteria by M. Çankaya; M. Şişecioğlu; Ö. Barış; M. Güllüce; H. Özdemir (pp. 57-60).
Bovine lactoperoxidase (LPO) was purified from skimmed milk using amberlite CG-50-H+ resin, CM sephadex C-50 ion-exchange chromatography, and sephadex G-100 gel filtration chromatography. Lactoperoxidase was purified 20.45-fold with a yield of 28.8%. Purity of enzyme checked by sodium dodecyl sulphate-polyacrylamide gel electrophoresis method and a single band was observed. K m was 0.25 mM at 20°C, V max value was 7.95 μmol/ml min at 20°C (pH 6.0). Antibacterial study was done by disk diffusion method of Kirby-Bauer using Mueller-Hinton agar medium with slight modification. Bovine LPO showed high antibacterial activity in 100 mM thiocyanate-100 mM H2O2 medium for some bacteria (Brevibacillus centrosaurus, B. choshinensis, B. lyticum, Cedecea davisae, Chryseobacterium indoltheticum, Clavibacter michiganense pv. insidiosum, Kocuria erythromyxa, K. kristinae, K. rosea, K. varians, Paenibacillus validus, Pseudomonas syringae pv. populans, Ralstonia pickettii, Rhodococcus wratislaviensis, Serratia fonticola, Streptomyces violaceusniger, Vibrio cholerae-nonO1) respectively, and compared with well known antibacterial substances (levofloxacin, netilmicin). LPO system has inhibition effects on all type bacteria and concentration is really important such as LPO-100 mM thiocyanate-100 mM H2O2 system was proposed as an effective agent against many factors causing several diseases.
Electrooptical properties of the microbial suspensions during a cell’s interaction with the antibodies of a different specificity by O. I. Gulii; L. Yu. Matora; G. L. Burygin; L. A. Dykman; V. V. Ignatov; O. V. Ignatov (pp. 61-64).
The electrooptical abilities of the microbial suspensions during a cells interaction with antibodies (ABs) of a different specificity have been studied on the example of the Azospirillum brasilense Sp245 cells and their interaction with the polyclonal monospecific and polyspecific antibodies. Measuring of the orientational spectra of the cells has been performed using the ELUS electrooptical analyzer. A discrete frequency set of an orienting electric field (740, 1000, 1450, 2000, and 2800 kHz) was used. It has been shown that an interaction of the polyspecific AB with the investigated cells redoubles the value of an electrooptical signal of the cells’ suspension as compared with the monospecific antibodies. These findings can be used for a development a new method of microorganism detection.
Luminol oxidation by hydrogen peroxide with chemiluminescent signal formation catalyzed by peroxygenase from the fungus Agrocybe aegerita V.Brig. by M. M. Vdovenko; R. Ullrich; M. Hofrichter; I. Yu. Sakharov (pp. 65-68).
Conditions of luminol oxidation by hydrogen peroxide in the presence of peroxygenase from the mushroom Agrocybe aegerita V.Brig. have been optimized. The pH value (8.8) at which fungal peroxygenase produces a maximum chemiluminescent signal has been shown to be similar to the pH optimum value of horseradish peroxidase. Luminescence intensity changed when the concentration of Tris-buffer was varied; maximum intensity of chemiluminescence was observed in 40 mM solution. It has been shown that enhancer (p-iodophenol) addition to the substrate mixture containing A. aegerita peroxygenase exerted almost no influence on the intensity of the chemiluminescent signal, similarly to soybean, palm, and sweet potato peroxidases. Detection limit of the enzyme in the reaction of luminol oxidation by hydrogen peroxide was 0.8 pM. High stability combined with high sensitivity make this enzyme a promising analytical reagent.
7α-Hydroxylation of steroid 5-olefins by mold fungi by V. A. Andryushina; A. V. Druzhinina; V. V. Yaderets; T. S. Stytsenko; N. E. Voishvillo (pp. 69-74).
Hydroxylation activity of the mold fungi belonging to the orders Dothideales, Hypocreales, and Mucorales towards Δ5-3β-hydroxysteroids was studied. The fungi Bipolaris sorokiniana, Fusarium sp., and Rhizopus nigricans were able to introduce hydroxy group at position 7α; however, this ability was detected only at a low substrate load and with a low yield. A 7α-hydroxylase activity of the Curvularia lunata VKPM F-981 culture was shown for the first time. It was demonstrated that the studied strain was capable of stereo- and regioselective transformations of androstane 5-olefins at a load not less than 2 g/1. Conversion of pregnane steroids by this culture yielded both 7α- and 11β-hydroxy derivatives. The introduction of 7α-hydroxy group by this strain occurred concurrently with enzymatic hydrolysis of ester groups, which proceeded under mild conditions to give the corresponding alcohols in the cases of both 3-acetate of Δ5-androstenes and mono- and triacetates of Δ5-pregnenes.
Isolation, identification, and characteristics of the phytotoxin produced by the fungus Alternaria cirsinoxia by A. O. Berestetskii; O. S. Yuzikhin; A. S. Katkova; A. V. Dobrodumov; D. E. Sivogrivov; L. V. Kolombet (pp. 75-79).
An individual substance (20 mg/l) exhibiting phytotoxic properties, which, on the basis its spectral characteristics, was identified as zinniol, was obtained from the fungus Alternaria cirsinoxia. The nonspecific activity of this phytotoxin, with respect to plants of different families, was demonstrated. The minimum concentration (200 μg/ml) at which zinniol damages creeping thistle leaves and the median inhibition concentration (IC 50) for rat embryonic fibroblasts (264 μg/ml) were determined.
The creation of sugar beet transgenic plants expressing bar gene by Ya. V. Mishutkina; A. M. Kamionskaya; K. G. Skryabin (pp. 80-86).
The parameters of transformation using Agrobacterium tumefaciens EHA 105 for 5 domestic sorts and lines of sugar beet (Beta vulgaris L. var. saccharifera (Alef) Krass) were optimized. The system of transgenic tissue selection based on resistance to phosphinothricin, allowing to avoid the appearing of chimeric shoots among initial transformants was developed. The transgenic plants of sugar beet sorts Ramonskaya single seed 47, L’govskaya single seed 52 and RMS 73, and LBO 17 and LBO 19 lines expressing the gene of phosphinothricin acetyl transferase bar have been obtained. The resistance of these sorts and lines to the effect of phosphinothricin in vitro has been shown.
Role of lipoxygenase in the determination of wheat grain quality by M. D. Permyakova; V. A. Trufanov; T. A. Pshenichnikova; M. F. Ermakova (pp. 87-92).
Analysis of the correlation between endogenous lipoxygenase activity and 15 wheat grain quality parameters in three bread wheat populations has shown that enzyme activity influences the weight of 1000 grains, dough deformation energy, dough tenacity, and mixing properties. The correlations between the enzyme activity and the basic quality parameters are negative at high activity levels. The optimum values of specific lipoxygenase activity at which all quality parameters studied have the maximum values range from 108.5 ± 1.2 to 126.4 ± 1.9. It has been found that the ability of lipoxygenase to strengthen gluten is related to the lowering of dough extensibility.
Preparation and properties of isocitrate lyase isoforms from the cotyledons of Glycine max L. by A. T. Eprintsev; E. V. Dyachenko; T. V. Lykova; Chan Thi Hoang Kuen; V. N. Popov (pp. 93-98).
A four-stage purification procedure including ammonium sulfate precipitation and ion exchange chromatography on DEAE cellulose has been elaborated for isolation of isocitrate lyase (EC 4.1.3.1) isoforms from the cotyledons of soybean Glycine max L. Electrophoretically homogeneous preparations of two forms of the enzyme with specific activity of 5.28 and 5.81 U/mg protein have been obtained. Comparison of physicochemical, kinetic, and regulation characteristics of the isoforms obtained revealed fundamental differences between them. Thus, the isoform that migrated quickly in PAAG had a much lower affinity to isocitrate (K M — 50 μM) than the slowly migrating form (K M — 16 μM). It has been shown that the conservation of activity of the isoforms obtained depends on the presence of divalent cations (Mn2+ and Mg2+) in the medium. It is suggested to use the isoforms of isocitrate lyase isolated from soybeans for the development of biosensors for biochemical and kinetic assays.
The influence of 24-epibrassidinolide on the hormonal status of wheat plants under sodium chloride by A. M. Avalbaev; R. A. Yuldashev; R. A. Fatkhutdinova; F. A. Urusov; Yu. V. Safutdinova; F. M. Shakirova (pp. 99-102).
We studied the influence of the pretreatment of wheat seedling (Triticum aestivum L.) with 0.4 μM 24-epibrassidinolide (EB) on the growth and hormone status of plants under the influence of 2% NaCl. The pretreatment with EB promoted the lowering of the extent of the damaging influence of salinity on the growth of seedling. The important contribution to the realization of the protective action of EB in the pretreatment of plants is probably that of its ability to lower the level of stress-induced abscisic acid accumulation and the decrease in the content of indole-acetic acid. At the same time, the cytokinin concentration in plants pretreated with EB under salinity was practically the same as in plants without stress. This fact combined with data about the ability of EB to induce the increase in cytokinin content in wheat, obtained before, allowed us to assume that the protective action of EB on plants is connected, first of all, with the prevention of the decrease in level of hormones of cytokinin nature under salinity.
Galactomannan from the seeds of chinese honey locust (Gleditsia sinensis Lam.) by D. N. Oleynikov; A. V. Rohin (pp. 103-107).
By the hot water extraction method, galactomannan was extracted (4.5% yield of the seed mass) from the seeds of Chinese honey locust (Gleditsia sinensis Lam). It had a molecular weight of 1230 kDa, and its solutions had a high viscosity [η] of 1064 ml/g and optical activity [α]D of +21.4°. The polysaccharide consists of mannose and galactose residues in the molar ratio 2.69: 1. In the galactomannan macromolecule the backbone is formed by 1,4-β-D-mannopyranose residues, 37% of which are substituted by α-D-galactopyranose at C6. By 13C-NMR-spectroscopy, fragments of differently galactose-substituted mannobiose units were found to be in the galactomannan being studied: Man-Man, (Gal)Man-Man, and Man-Man(Gal) in the ratio of 0.23: 0.47: 0.30.
Formation of flavor of dry champignons (Agaricus bisporus L.) by T. A. Misharina; S. M. Muhutdinova; G. G. Zharikova; M. B. Terenina; N. I. Krikunova; I. B. Medvedeva (pp. 108-113).
The composition of aroma compounds of dry champignons (Agaricus bisporus L.) were identified using capillary gas chromatography and chromatography-mass spectrometry. In total, 56 compounds were identified. It was found that the flavor of dry mushrooms was formed by the volatile compounds produced as a result of enzymatic and oxidative conversion of unsaturated fatty acids as well as in the Maillard reaction. Unsaturated alcohols and ketones containing eight carbon atoms determined the mushroom note of the product. The specific aroma of dry mushrooms was determined by a complex composition of substituted sul- fur-, oxygen-, and nitrogen-containing heterocyclic compounds as well as by aliphatic carbonyl compounds and methional. It was found that the concentrations of volatile carbonylic and heterocyclic compounds increased after the addition of a mixture of amino acids to mushrooms before drying. As a result, the intensity of the aroma of dry mushrooms increased.