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Applied Biochemistry and Microbiology (v.36, #5)
Plant potential for detoxification (Review) by G. V. Zaalishvili; G. A. Khatisashvili; D. Sh. Ugrkhelidze; M. Sh. Gordeziani; G. I. Kvesitadze (pp. 443-451).
Data on the uptake, excretion, and biodegradation of organic xenobiotics by plants are reviewed. Detoxification pathways operating in plants and their role in remediation of the biosphere are described. Structure-, concentration-, and time-dependent effects of xenobiotics on the ultrastructural organization of cells are analyzed.
Properties and uses of protein hydrolysates (Review) by A. D. Neklyudov; A. N. Ivankin; A. V. Berdutina (pp. 452-459).
Properties of protein hydrolysates and possible uses of these substances in research and various branches of industry are considered. The main problem discussed in this paper is the relationship between the degree of protein conversion and characteristics (structural-functional and physicochemical) of hydrolysates.
Purification and Characterization of endo-(1→4)-β-xylanase fromGeotrichum candidum 3C by N. A. Rodionova; N. V. Dubovaya; E. V. Eneiskaya; L. I. Martinovich; I. M. Gracheva; A. M. Bezborodov (pp. 460-465).
A method of purification of endo-( 1 → 4)-β-xylanase (endoxylanase; EC 3.2.1.8) from the culture liquid ofGeotrichum candidum 3C, grown for three days, is described. The enzyme, purified 23-fold, had a specific activity of 32.6 U per mg protein (yield, 14.4%). Endoxylanase was shown to be homogeneous by SDS-PAGE (molecular weight, 60 to 67 kDa). With carboxymethyl xylan as the substrate, the optimum activity (determined viscosimetrically) was recorded at pH 4.0 (pI 3.4). The enzyme retained stability at pH 3.0-4.5 and 30–45°C for 1 h. With xylan from birch wood, the hydrolytic activity of the enzyme (ability to saccharify the substrate) was maximum at 50°C. In 72 h of exposure to 0.2 mg/ml endoxylanase, the extent of saccharification of xylans from birch wood, rye grain, and wheat straw amounted to 10,12, and 7.7%, respectively. At 0.4 mg/ml, the extent of saccharification of birch wood xylan was as high as 20%. In the case of birch wood xylan, the initial hydrolysis products were xylooligosaccharides with degrees of polymerization in excess of four; the end products were represented by xylobiose, xylotriose, xylose, and acid xylooligosaccharides.
A trypsin inhibitor from amaranth (Amaranthus cruentus) leaves by E. V. Levleva; Yu. A. Rudenskaya; A. V. Zimacheva; V. V. Mosolov (pp. 466-468).
A protein that inhibited the proteolytic activity of trypsin was isolated from amaranth leaves (Amaranthus cruentus) by affinity chromatography on trypsin-Sepharose. The inhibition was noncompetitive (withp-nitroanilide-N-α-benzoyl-DL-arginine as substrate) and had aK i, of 1.87 × 10−7 M. The protein caused a weaker inhibitory effect on chymotrypsin, had no effect on subtilisin, displayed a molecular weight of 8 kDa, and contained no cysteine residues.
Optimization of the medium and conditions for cultivatingErwinia sp., a producer of fumarase and aspartase by Z. N. Bagdasaryan; G. A. Aleksanyan; G. S. Gukasyan; A. M. Mirzoyan (pp. 469-472).
Mathematical methods of experimental design were used to determine the optimal concentrations of nutrient medium components, aeration conditions, and pH providing for the maximum biomass yields, as well as fumarase and aspartase activities, during submerged cultivation ofErwinia sp. The data showed that different concentrations of carbon source (molasses) and pH of the nutrient medium were required to reach the maximum yields of fumarase and aspartase. Calculations suggested that the combination of these optimized factors would result in 3.2-, 3.4-, and 3.8-fold increases in theErwinia sp. biomass, aspartase activity, and fumarase activity yields, respectively. The experimental data were consistent with these estimates to 80% accuracy.
Effect of membrane-active microbial autoregulators on the growth of culturedras-transformed fibroblasts by O. N. ll’inskaya; A. I. Kolpakov; A. L. Mulyukin; F. Dreyer; G. I. El’ Registan (pp. 473-477).
Differential effects on the proliferation of individual vs. combined administration of high-and lowmolecular-weight microbial autoregulators (extracellular RNase fromBacillus intermedius and anabiosis inducing factord 1) are reported for the first time for cultured cells of higher eukaryotes. Proliferation ofras- transformed mouse fibroblasts was affected by both autoregulators dose-dependently. The cytotoxic activity of individual regulators was directly related to their concentration. Unlike RNase, factord 1 (which functions as a chemical chaperone) exerted reversible effects. Studies of the effects of combined administration of the autoregulators demonstrated that pretreatment of the cells with low-dosed 1 decreased the toxicity of RNase. Higher doses ofd 1 were required to attenuate the effects of toxic agents with more pronounced membrane tropism. The results obtained suggest that a universal system regulating the physiological activity of cells is operative in taxonomically remote organisms. The operation of the system is based on sequential changes in the structural organization and function of subcellular structures induced by low-and high-molecular-weight autoregulators.
Respiratory activity of the bacteriumAcinetobacter calcoaceticus TM-31 during assimilation of alkane hydrocarbons by O. V. Ignatov; E. V. Grechkina; A. Yu. Muratova; O. V. Turkovskaya; V. V. Ignatov (pp. 478-480).
The respiratory activity ofAcinetobacter calcoaceticus TM-31 with resect to alkane hydrocarbons was studied. The dynamics of oxygen consumption by the cells while assimilatingn-hexadecane was assayed by a modified technique using an oxygen electrode. The dependence of cell respiratory activity on the amount ofn-hexadecane within the concentration range of 0.03–0.66% was determined. It was demonstrated that the cells also displayed respiratory activity towards other medium-chainn-alkanes: hexane, octane, decane, tridecane, and heptadecane. Thus, we demonstrated the possibility of determining alkanes by measuring the respiratory activities of microorganisms.
Effects of bulk discharges of oil products on sludge microbiocenoses of purification works and their functions by T. V. Sandanova; S. A. Soktoev; B. B. Namsaraev; V. Zh. Tsyrenov (pp. 481-485).
The effects of two bulk discharges of oil products on the microbiocenoses and functioning of bioactive sludge in the purification works of Ulan-Ude city were investigated. Pollution with oil products exerted both a direct toxic effect on the microorganisms and an indirect effect via food chains. No toxic effects of oil products on sludge-nitrifying bacteria were found.
An antibiotic complex produced byStreptomyces werraensis 1365T by E. P. Rusanova; T. A. Alekhova; G. B. Fedorova; G. S. Katrukha (pp. 486-490).
An antibiotic complex comprising four components (A, B, C, and X) was extracted from a native solution and myceliumof Streptomyces werraensis 1365T. The components were purified by column and thinlayer (TLC) Chromatographic procedures to study their physicochemical and biological properties. The results were used to identify the substances isolated. The preliminary data allowed us to identify the components X, A, and B as the previously described compounds undecylprodigiosin, anisomycin, and copiamycin, respectively, whereas component C is a natural compound which has probably never been described.
Antioxidant properties of fungal melanin pigments by V. V. Shcherba; V. G. Babitskaya; V. P. Kurchenko; N. V. Ikonnikova; T. A. Kukulyanskaya (pp. 491-495).
Fungal melanin pigments were shown to display a high antioxidant activity. An increase in the number of methyl substituents in benzidine molecules of melanins obtained from micromycetes and macromycetes was accompanied by a decrease in the efficiency of inhibition of peroxidase-mediated oxidation. Melanins were found to have considerable gene-protecting properties. Pigments isolated from macromycetes and applied at a much lower concentration than those obtained from micromycetes prevented damage to bacteriophage-λ DNA induced by products of peroxidase-mediated degradation of aminobiphenyls.
Comparative immunochemical characterization of polyclonal and monoclonal antibodies to aflatoxin B1 by M. A. Burkin; I. V. Yakovleva; V. V. Sviridov; A. A. Burkin; G. P. Kononenko; N. A. Soboleva (pp. 496-501).
Four hybrid clones (MM-(AB1)-1, MM-(AB1)-2, MM-(AB1)-3, and MM-(AB1)-4) were obtained by hybridoma technology involving the immunization of BALB/c mice with a BSA conjugate of aflatoxin B1 carboxymethyloxime derivative. Antibodies produced by these clones varied in their ability to recognize the aflatoxin B1 analogues. The sensitivity of enzyme immunoassay based on all monoclonal antibodies was higher compared to analysis based on polyclonal rabbit antibodies (0.1 and 0.4 ng/ml, respectively).
Composition and structure of a galactomannan macromolecule from seeds ofAstragalus lehmannianus bunge by N. M. Mestechkina; O. V. Anulov; N. I. Smirnova; V. D. Shcherbukhin (pp. 502-506).
The composition and structure of a galactomannan from seeds ofAstragalus lehmannianus, an endemic legume species, is reported for the first time. The purified galactomannan (yield, 4.8%) contained 55% D-mannose and 45%D-galactose and had a molecular weight of 997.03 kDa. Its aqueous solutions were optically active and highly viscous (the specific rotation [α]D equaled +81.3°; the characteristic viscosity [η], 868.4 ml/g). Chemical, Chromatographic, and spectral (IR and13C-NMR spectroscopy) methods were used to demonstrate that the main chain of the molecule is formed by residues of 1,4-β-D-mannopyranose, 78% of which are substituted at position 6 with single α-D-galactopyranose. The distribution of galactose along the chain was calculated from NMR spectra: frequencies of occurrence per pair of neighboring mannose units of ( 1 ) two substituents, (2) one substituent, and (3) no substituents were 65.3%, 31.5, and 3.2, respectively. The specific rotation of the galactomannans was shown to correlate with their content of galactose.
Effects of gibberellin and auxin on the synthesis of abscisic acid and ethylene in buds of dormant and sprouting potato tubers by M. Z. Dogonadze; N. P. Korableva; T. A. Platonova; G. L. Shaposhnikov (pp. 507-509).
Gibberellic and β-indolylacetic acids at concentrations of 10−7-10−5 M were shown to change the hormonal status and duration of true dormancy in potato tubers. Gibberellic acid shortened the true dormancy and decreased the contents of abscisic acid and ethylene in the apical meristem. β-Indolylacetic acid elongated the true dormancy and decreased abscisic acid production, but caused a more than tenfold increase in the production of ethylene by apical tissues. The data suggest that β-indolylacetic acid and ethylene, as well as gibberellic and abscisic acids, are involved in the regulation of true dormancy in potato tubers.
Cytoplasmic protein vaccine against bacterial hemorrhagic septicemia (Aeromonosis) of fish by L. P. Smirnov; V. V. Bogdan; N. N. Nemova; L. N. Yukhimenko (pp. 510-513).
Water-soluble proteins fromAeromonas sobria, a causative agent of bacterial hemorrhagic septicemia of fish, were separated into six fractions by gel chromatography on Sephadex G-100. Injections of fraction II (67 kDa) provided the highest protection of carp against the disease. Injections of proteins contained in fraction II caused stronger effects on certain biochemical parameters in the fish liver (fatty acids of phospholipids and cathepsin B and D activities) in comparison to infections of the live culture.
Lipopolysaccharides ofShigella sonnei by E. V. Borisova; V. A. Borisov (pp. 514-518).
Immunobiological properties of native lipopolysaccharides (LPS) from virulent and avirulent strains ofShigella sonnei bacteria (LPS-V and LPS-A, respectively) were studied. In avirulent bacteria, LPS-V induced immunosuppressive activity specific to the virulent strain, whereas LPS-A lacked this property. Native LPS-V with immunosuppressive activity were isolated from the virulent strain by and immune affinity method. Treatment of LPS-V with phenol or TCA abolished its activity and converted it into the LPS-A form. The data showed that LPS-A can be converted back to the LPS-V form by redox treatment. This approach seems to be promising for activating LPS extracted from cells with TCA or a water-phenol mixture.
Congratulations to Igor’ Stepanovich Kulaev on the seventieth anniversary of his birth
(pp. 519-520).
The 90th Anniversary of Sergei Vasil’evich Durmishidze, Member of the Georgian Academy of Sciences (1910-1989)
(pp. 521-521).
The Fourth International Workshop on Biosensors I and Biological Techniques in Environmental Analysis, I Menorca, Spain I
by A. N. Reshetilov (pp. 522-525).