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Applied Biochemistry and Microbiology (v.42, #4)
Aerobic processing of organic waste into composts by A. D. Neklyudov; G. N. Fedotov; A. N. Ivankin (pp. 341-353).
The current achievements in the field of aerobic waste processing into composts are reviewed, with an emphasis on amelioration of the environment and targeted use for intensification of agriculture. The methods for obtaining microbiological transformation products of household, agricultural, and industrial waste and their characteristics are analyzed.
Modification of a catalase by glutaraldehyde by R. N. Mishaeva; L. R. Gudkin; N. P. Kuznetsova (pp. 354-359).
Polycondensation of a catalase (EC 1.11.1.6) with glutaraldehyde in order to stabilize the quaternary structure of an enzyme, maintain its activity, and protect it from thermal denaturation was studied. Synthesis showed a superequivalent utilization of the aldehyde groups relative to the catalase amine groups, as a result of the formation of glutaraldehyde oligomers linked to the enzyme.
Dependence of equilibrium and kinetic parameters of erythromycin a sorption on the structural characteristics of the biosorbent by I. S. Garkushina; N. M. Ezhova; O. A. Pisarev (pp. 360-363).
The use of special synthetic sorbents with surface carboxyl groups allowed us to increase fourfold the effective diffusion coefficient for erythromycin. The maximum sorption capacity for the antibiotic exceeded twofold that observed in experiments with a macroporous sulfocation exchanger MN-500. The sorption of the antibiotic was completely reversible upon treatment with a combined eluant that competitively interacts with the sorbent and does not impair the structural characteristics of erythromycin.
Carbohydrate specificity of lectins from luminous bacteria by G. A. Vydryakova (pp. 364-368).
The presence of lectins on a cell surface was demonstrated for 70 cultures of luminous bacteria using hemagglutination reactions. It was shown that hemagglutination of luminous bacteria is inhibited by glucose, maltose, fructose, mannose, and N-acetyl-D-glucosamine. The differences in the inhibition of hemagglutination of luminescent and nonluminescent (spontaneous mutants) symbiotic cultures by N-acetyl-D-galactosamine were revealed. The fact that N-acetyl-D-galactosamine inhibits hemagglutination of the luminescent symbiotic bacteria but does not inhibit hemagglutination of the symbiotic cultures lacking luminescence suggests that lectins with N-acetyl-D-galactosamine specificity are possibly involved in the formation and functioning of the symbiosis of luminous bacteria with marine animals possessing luminous organs.
Physiological changes induced in four bacterial strains following oxidative stress by S. Baatout; P. De Boever; M. Mergeay (pp. 369-377).
In order to study the behavior and resistance of bacteria under extreme conditions, physiological changes associated with oxidative stress were monitored using flow cytometry. The study was conducted to assess the maintenance of membrane integrity and potential as well as the esterase activity, the intracellular pH and the production of superoxide anions in four bacterial strains (Ralstonia metallidurans, Escherichia coli, Shewanella oneidensis and Deinococcus radiodurans). The strains were chosen for their potential use in bioremediation. Suspensions of R. metallidurans, E. coli, S. oneidensis and D. radiodurans were submitted to 1 h of oxidative stress (H2O2 at various concentrations from 0 to 880 mM). Cell membrane permeability (propidium iodide) and potential (rhodamine-123,3,3’-dihexyloxacarbocyanine iodide), intracellular esterase activity (fluorescein diacetate), intracellular-reactive oxygen species concentration (hydroethidine) and intracellular pH (carboxy-fluorescein diacetate succinimidyl ester 5-(6)) were monitored to evaluate the physiological state and the overall fitness of individual bacterial cells under oxidative stress. The four bacterial strains exhibited varying sensitivities towards H2O2. However, for all the bacterial strains, some physiological damage could already be observed from 13.25 mM H2O2 onwards, in particular with regard to their membrane permeability. Depending on the bacterial strains, moderate to high physiological damage could be observed between 13.25 mM and 220 mM H2O2. The membrane potential, esterase activity, intracellular pH and production of superoxide anion production were in all four strains considerably modified at high H2O2 concentrations. In conclusion, we show that a range of significant physiological alterations occur when bacteria are challenged with H2O2 and fluorescent staining methods coupled with flow cytometry are used for monitoring the changes induced not only by oxidative stress, but also by other stresses like temperature, radiation, pressure, pH, etc.
A positive effect of Propionibacterium freudenreichii on the growth of Saccharomyces cerevisiae during their cocultivation by I. V. Danilova; T. V. Bykovchenko; E. P. Ryzhkova (pp. 378-383).
The growth pattern of Saccharomyces cerevisiae and Propionibacterium freudenreichii ssp. shermanii (P. shermanii; propionic acid bacteria, PABs) during cocultivation in liquid media depended on the ratio of the cells in the inoculum. An increase in the growth rate of S. cerevisiae was observed at a PAB to yeast ratio of approximately 3: 1; higher ratios exerted adverse effects on yeast growth. The culture liquid of 18-to 24-h (young) cultures of PABs stimulated yeast growth. Although yeast growth-stimulating exometabolites of PABs were not high-molecular-weight compounds, they were thermolabile. When present in the medium at concentrations of up to 1.5%, the antimicrobial agent sodium propionate did not interfere with S. cerevisiae growth; however, it completely inhibited the growth of B. subtilis at a concentration of 0.2%.
Stability study on the nitrile hydratase of Nocardia sp. 108: From resting cells to crude enzyme preparation by Y. J. Wang; Y. G. Zheng; R. C. Zheng; Y. C. Shen (pp. 384-387).
In recent years nitrile hydratases (NHases) have drawn increasing attention due to their critical roles in organic synthesis. In the present paper an extensive investigation on the stability and activity of NHase from Nocardia sp. 108, which has succeeded in industrial application in China, was conducted by bioconversion of acrylonitrile to acrylamide in a batch manner. A study of cultivation demonstrated that biosynthesis of NHase changed significantly with the time of the culture, and the optimal NHase biosynthesis phase was 45 h after inoculation with NHase activity of a biomass of 1209.8 U/g. A stability study indicated that both crude enzyme preparations exhibited a good stability when exposed to a pH 7.2 tris-HCl buffer at 4°C for 4 h.
Effect of argillaceous minerals on the growth of phosphate-mobilizing bacteria Bacillus subtilis by I. K. Kurdish; Z. T. Bega (pp. 388-391).
It was shown that the argillaceous minerals montmorillonite and palygorskite at concentrations within 0.2–1.0% considerably accelerate the growth of phosphate-mobilizing bacteria Bacillus subtilis grown in media with hardly soluble Ca3(PO4)2 as the sole source of phosphorus. The most notable effect of these minerals was recorded at concentrations within 0.5–1%. The effect of argillaceous minerals in the colloidal form on bacterial growth was more pronounced than that of the powdered ones. An increase in montmorillonite or palygorskite concentrations to 2% is accompanied by the inhibition of the growth of the phosphate-mobilizing strain. At such concentrations the minerals adsorb ca. 22% of the glucose and 11.3% of the phosphate added to the nutrition medium.
Catalysis of the biodegradation of unusable medicines by Alkanotrophic rhodococci by I. B. Ivshina; M. I. Rychkova; E. V. Vikhareva; L. A. Chekryshkina; I. I. Mishenina (pp. 392-395).
Experiments on the biodegradation of unusable medicines containing a phenolic hydroxy group by actinobacteria of the genus Rhodococcus were performed. Six species and sixty-four strains were tested. It was found that rhodococci could degrade paracetamol, and some R. ruber strains showed high levels of its degradation. An efficient method for the identification and quantification of paracetamol and the products of its conversion (p-aminophenol, pyrocatechol, and hydroquinone) immediately in the culture liquid was developed. Conditions for the complete biodegradation of paracetamol dosage forms (pills) were optimized. The experimental results can be applied to the development of biotechnological methods for degrading medicines: faked, rejected, or those that are expired.
Improvement of the process of fluorene degradation by Rhodococcus rhodochrous strain 172 by G. E. Rubashko; M. P. Kolomytseva; L. A. Golovleva (pp. 396-398).
The ability of Rhodococcus rhodochrous strain 172 to consume fluorene as the sole source of carbon and energy in a liquid medium was successfully increased by an addition of polycapramide fiber to the medium and preliminary adaptation of cells on fluorene agar. A combination of these approaches allowed complete degradation of fluorene without an accumulation of intermediates.
Cooxidation of phenol and 4-aminoantipyrin, catalyzed by polymers and copolymers of horseradish root peroxidase and Penicillium funiculosum 46.1 glucose oxidase by A. N. Eryomin; T. V. Semashko; R. V. Mikhailova (pp. 399-408).
Polymers and copolymers of horseradish root peroxidase (HRP) and Penicillium funiculosum 46.1 glucose oxidase (GO) have been synthesized and their catalytic properties have been characterized (free and immobilized forms of each enzyme were studied). The cooxidation reaction of phenol and 4-aminoantipyrin (4-AAP), performed in an aqueous medium in the presence of equimolar amounts of GO and HRP, was characterized by effective K M and k cat of 0.58 mM and 20.9 s−1 (for phenol), and 14.6 mM and 18.4 s−1 (glucose), respectively. The catalytic efficiency of polymerization products (PPs) of GO (GO-PPs) depended on the extent of their aggregation. The combinations GO + HRP-PP and HRP + GO-PP, as well as the copolymer HRP*-GO-PP, proved promising as reagents for enzyme-based analytical systems. When adsorbed on aluminum hydroxide gels, GO-PPs exhibited higher catalytic activity than the non-polymeric enzyme. Maximum retention of GO-PP activity on the inorganic carrier was observed in the case of GO-PP copolymers with an activated HRP. Polymerization of HRP in the presence of a zinc hydroxide gel, paralleled by HRP-PP immobilization onto the gel, increased both the activity of the enzyme and its operational stability.
The effect of thaumatin gene overexpression on the properties of H+-ATPase from the plasmalemma of potato tuber cells by E. P. Ladyzhenskaya; N. P. Korableva (pp. 409-413).
The introduction of the thaumatin gene into potato plants was accompanied by a decrease in the activity of H+-ATPase in the plasmalemma (PL) of tuber cells. When tubers were released from dormancy, the enzyme was activated in the tuber cells of both the original and transgenic plants. Experiments performed in vitro demonstrated that sensitivities to ambiol (AM) and jasmonic acid (JA) of H+-ATPase in the PL of tubers from the original plants were lower after the release from a period of deep dormancy. In preparations from the tubers of transgenic plants, the situation was reversed. The differences between the activities of H+-ATPase in the PL preparations produced from the original and transgenic tubers that sprouted under the action of AM and JA were detected. Thus, the overexpression of the thaumatin gene in potato plants changed the properties of H+-ATPase from PL.
Increase of the detoxification potential of basidiomycetes by induction of laccase biosynthesis by O. N. Gorbatova; O. V. Koroleva; E. O. Landesman; E. V. Stepanova; A. V. Zherdev (pp. 414-419).
The effect of oxidoreductase inducers guaiacol and syringaldazine on the ability of Coriolus hirsutus, Coriolopsis fulvocinerea, Cerrena maxima, and cocultivated Coriolus hirsutus/Cerrena maxima to degrade atrazine in submerged cultures was studied. All the basidiomycetes reduced atrazine concentration with and without syringaldazine or guaiacol. The degree of atrazine degradation was higher in induced cultures (77–98% vs. 68–94% without induction). Of the four cultures, the highest detoxifying potential was observed in Coriolopsis fulvocinerea with and without an inducer (98% with guaiacol), and the lowest was in Cerrena maxima. Inducers decreased the residual atrazine concentration differently in the different cultures. A long-term increase of laccase production was observed in both induced and uninduced cultures, whereas the activity of Mn-peroxidase decreased. The results indicate that laccase plays a larger role in atrazine biodegradation than Mn-peroxidase.
Regulatory role of elements in the formation and accumulation of alkaloids in Papaver somniferum L. seedlings by M. Ya. Lovkova; G. N. Buzuk; S. M. Sokolova (pp. 420-423).
The effects of 12 elements on the formation and accumulation of isoquinolines were studied in opium poppy seedlings (Papaver somniferum L.). Three types of concentration dependences of the effects of the elements under study were determined. The elements served as activators (Co, Mo, W, Cr, and Cu) or inhibitors of these processes (B, Fe, V, Mn, and Ca). The molecular mechanisms of action of these regulators are discussed. The optimum concentrations of Co and Mo were tested under combined treatment conditions with these elements.
Identification of AGR2 protein, a novel potential cancer marker, using proteomics technologies by L. I. Kovalyov; S. S. Shishkin; P. Z. Khasigov; N. K. Dzeranov; A. V. Kazachenko; M. A. Kovalyova; I. Yu. Toropygin; S. V. Mamykina (pp. 424-427).
A comparative analysis of the proteins in prostate tissues of the patients operated for hyperplasia (n = 7) or cancer (n = 5) was performed aiming to search for protein diagnostic markers. Differences in several minor proteins were detected using two-dimensional electrophoresis according to O’Farrel; among them, an additional protein with a molecular weight of 19 kDa and an isoelectric point of 9.0 was observed in four of the cancer cases. Mass spectrometry allowed this protein to be identified as the androgen-induced secreted protein AGR2. The possibility of using AGR2 as a diagnostic marker of prostate cancer is discussed.
Accuracy of a real-time polymerase-chain-reaction assay for a quantitative estimation of genetically modified sources in food products by D. D. Abramov; D. Yu. Trofimov; D. V. Rebrikov (pp. 428-430).
The accuracy of a real-time polymerase-chain-reaction assay for genetically modified sources in food products was determined using two official test systems (kits) of primers and samples. These kits were recommended by the Federal Center of State Sanitary and Epidemiological Surveillance (Russian Ministry of Health) and the European Commission. We used the following three models of thermocyclers: iCycler iQ (Bio-Rad, United States), Rotor-Gene 3000 (Corbett Research, Australia), and DT-322 (DNA-Technology, Russia). Studies of samples that contained 1% genetically modified sources showed that the error of a quantitative assay for genetically modified sources in food products corresponds to 20–30% and does not depend on the kit type and the thermocycler model used.
Collagenolytic activity in several species of deuteromycetes under various storage conditions by M. B. Yakovleva; T. L. Khoang; Z. K. Nikitina (pp. 431-434).
The ability of deuteromycetes of the genera Penicillium, Aspergillus, and Botrytis to retain collagenolytic activity was studied after both 2 and 10 years of storage on a Czapek medium under a layer of mineral oil at 4°C, as well as in silica gel granules at 20 and −60°C. The enzymatic activity of several species, including Botrytis terrestris, Penicillium janthinellum, Penicillium chrysogenum, and Penicillium citrinum, was retained under both conditions of storage. Aspergillus repens retained enzymatic activity only if stored under a layer of mineral oil. The viability of conidia and the collagenolytic activity of Botrytis terrestris, P. janthinellum, P. chrysogenum, and Penicillium citrinum, maintained on silica gel for 10 years, depended on the storage temperature. The viability of the test strains improved after storage on a silica gel at −60°C. A strain of Aspergillus repens lost its ability to dissolve collagen at various storage tempeatures on the silica gel. The index of lysis for three strains of Penicillium deuteromycetes (Penicillium janthinellum, Penicillium chrysogenum, and Penicillium citrinum) increased after a 10-year storage on silica gel at −60°C.
The Eighth International Seminar Presentation of Innovation Research Projects “Biotechnology-2005”
by T. A. Reshetilova (pp. 435-438).