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Applied Biochemistry and Microbiology (v.42, #1)
Ethanol production from materials containing cellulose: The potential of Russian research and development by M. L. Rabinovich (pp. 1-26).
Development of national research of cellulose-degrading microorganisms and enzymes is reviewed, with emphasis on the prospects of producing ethanol from cellulose materials using cellulolytic enzymes. Leading Russian research groups in this field are introduced. A section of the review analyzes problems and prospects of setting up environmentally friendly production of motor biofuels from renewable raw materials of plant origin (an approach developed in Russia).
Structure and functional properties of temperature-sensitive derivatives of immobilized proteins by L. I. Valuev; I. L. Valuev; I. M. Shanazarova (pp. 27-30).
Polydiethylacrylamides (degree of polymerization, 13–470) containing a terminal carboxyl group were obtained by the method of radical polymerization of N,N-diethylacrylamide in the presence of mercaptoacetic acid. In the presence of 1-ethyl-(3,3-dimethylaminopropyl)-carbodiimide, these polymers reacted with ovomucoid to produce its polymeric derivatives. The values of the lower critical mixing temperature of these derivatives and the inhibitory activities of immobilized ovomucoid were determined by the length and amount of polydiethylacrylamide macromolecules bound to the molecule of ovomucoid.
Combined enzymatic modification of stevioside and rebaudioside A by V. T. Kochikyan; A. A. Markosyan; L. A. Abelyan; A. M. Balayan; V. A. Abelyan (pp. 31-37).
Cyclodextrin glucanotransferases (CGTases, EC 2.4.1.19) produced by mesophilic, thermophilic, alkaliphilic, and halophilic bacilli were used for transglycosylating stevioside and rebaudiosides A with the use of starch as a donor. CGTases produced by Bacillus stearothermophilus B-5076 B. Macerans BIO-4m were the most effective biocatalysts. This method can be used successfully for direct transglycosylation of stevia extract without purification of its individual components.
Biochemical and photochemical degradation of the herbicide Lontrel by E. A. Saratovskikh; N. B. Kozlova; V. G. Papin; E. V. Shtamm (pp. 38-44).
Degradation of Lontrel by activated sludge (AS) from treatment plants and UV irradiation was studied. 3,6-Dichloropicolinic acid (3,6-DCPA, the main active principle of Lontrel) was not degraded by the microbial association of the AS. AS treated with nitrosourea under various conditions did not oxidize Lontrel either. Hard UV radiation degraded 3,6-DCPA within 4–24 h in the presence of constant sparging (bubbling) of air, oxygen, or ozone. The rate of oxidation in the presence of oxygen or ozone bubbling was three to four times higher than in the presence of air bubbling. It was found that the products of photochemical degradation of Lontrel were also toxic; however, they were readily degraded by AS microorganisms without additional AS treatment.
Biodegradation of methyl and ethyl acetates by immobilized Pseudomonas esterophilus cells by N. V. Doronina; N. M. Nazarov; V. A. Ezhov; Yu. A. Trotsenko (pp. 45-47).
A biofilter was created based on polyvinylformal foam and Pseudomonas esterophilus strain VKM V-1436D cells, which utilize methyl and ethyl acetates as sources of carbon and energy. A complete conversion of methyl and ethyl acetate (2000 mg/l) under flow conditions was reached. Because carboxyl esterase does not exhibit specificity for these esters, no adaptation period was required for switching the biofilter between biodegradation of methyl acetate and ethyl acetate.
Consumption of water-insoluble phenolic products of lignin pyrolysis by the strain Penicillium tardum H-2 by E. A. Karetnikova (pp. 48-51).
Physiological and biochemical properties of the strain Penicillium tardum H-2, a degrader of phenolic compounds formed during lignin pyrolysis, have been characterized. The micromycete P. tardum H-2 can consume phenol, catechol, p-cresol, vanillin, and guaiacum tar. When grown in a medium containing a water-soluble fraction of lignin pyrolysis waste at concentrations from 0.5 to 2%, it consumes 62–72% of the phenolic components of the waste. According to gas-liquid chromatography, cultivation of P. tardum H-2 in a medium with liquid pyrolysis products results in a complete consumption of the phenol-cresol fraction.
Degradation and solubilization of Chinese lignite by Penicillium sp. P6 by H. L. Yuan; J. S. Yang; F. Q. Wang; W. X. Chen (pp. 52-55).
Penicillium sp. P6, isolated from coal mine soil at the Qiantong colliery, Liaoning Province, Northwest China, can degrade Chinese lignite in 36 h on a plate colony and in 48 h, using a four-day cultured cell-free filtrate. Results of elemental analysis and IR spectrometry indicated that solubilized products exhibited some alterations in comparison to the original lignite. The amount of fulvic acid extracted from the biodegraded lignite was high, and the molecular distribution of humic acids from biodegraded lignite changed distinctively in comparison to that extracted from control lignite, possibly due to the depolymerization associated with fungal biodegradation.
Yellow laccase from the fungus Pleurotus ostreatus D1: Purification and characterization by N. N. Pozdnyakova; O. V. Turkovskaya; E. N. Yudina; Ya. Rodakiewicz-Nowak (pp. 56-61).
Yellow laccase was isolated from a solid-phase culture of the fungus Pleurotus ostreatus D1 and characterized. It is a copper-containing enzyme with a molecular weight of 64 kDa. Its lacks an absorption spectrum maximum at 610 nm, a result which is characteristic of fungal laccases and corresponds to the presence of type I copper atoms. The optimum pH values for the enzyme are determined. They prove to be 7.0 for syringaldazine, 8.0 for pyrocatechol, and 4.0 for 2,2′-azine-bis-(3-ethylbenzothiazoline-6-sulfonate and 2,6-dimethoxyphenol. Kinetic parameters (K m and V max) for oxidation of these substrates are determined. The effect of inhibitors (SDS, 2-mercaptoethanol, and EDTA) on the activity of the enzyme is studied. It is shown that yellow laccase from Pleurotus ostreatus D1 in the absence of a mediator oxidizes anthracene to anthraquinone to 95%.
Use of antagonistic bacilli for biocontrol of fungi degrading fresh wood by A. I. Melent’ev; P. Helisto; L. Yu. Kuz’mina; N. F. Galimzyanova; G. E. Aktuganov; T. Korpela (pp. 62-66).
The species composition of micromycete complexes colonizing aspen, birch, and pine wood was studied. Calculation of the Sorens-Tchekanovsky similarity coefficients showed that these complexes shared a high degree of similarity. They were dominated by representatives of the genera Penicillium, Paecilomyces, Trichoderma, and Rhizopus. Some antagonistic bacilli inhibited growth and development of wood-decay fungi in vitro and led to the formation of spheroplasts on growing hyphae. A study of possible involvement of bacillary mycolytic enzymes in the inhibition of wood-decay fungi demonstrated selectivity of their lytic effect, which was determined by the genus and species of micromycetes and did not correlate with their relative resistance to antagonists.
The effect of a preparation from Chaetomium fungi on the growth of phytopathogenic fungi by O. G. Tomilova; M. V. Shternshis (pp. 67-71).
We studied the fungicidal activity of a biological preparation from the fungi of the genus Chaetomium against soil phytopathogenic fungi Rhizoctonia solani and Fusarium oxysporum. The inhibitory effect of the preparation under study depended on its concentration, duration of storage, and growth characteristics of pure cultures of the phytopathogens. The highest (98.8%) inhibitory activity was observed on the third day of the interaction with Rhizoctonia solani. After a 2-year storage, this preparation was capable of inhibiting the growth of phytopathogens only at high doses. The preparation precluded the development of a bare patch but increased the productivity of potato plants. The preparation may serve as an alternative to chemical fungicides for plant protection.
Effects of nutrient medium composition and temperature on the germination of conidia and the entomopathogenic activity of the fungi Beauveria bassiana and Metarhizium anisopliae by U. S. Iskandarov; A. G. Guzalova; K. D. Davranov (pp. 72-76).
The effects of nutrient medium composition and temperature on the germination of conidia of the fungi Beauveria bassiana (strain AlG) and Metarhizium anisopliae (strain M-99) and their entomopathogenic activity have been studied. It was demonstrated that the presence of carbohydrates alone was sufficient for the spores of M. anisopliae M-99 to germinate, whereas the germination of B. bassiana AlG spores was inhibited by carbohydrates. Addition of KJ, ZnSO4, or KBr into the Czapek medium increased the entomopathogenic activity of B. bassiana. The optimum temperature for spore germination was 20–35°C in both fungal species.
Biological preparations with different mechanisms of action for protecting potato against fungal diseases by S. N. Kulikov; F. K. Alimova; N. G. Zakharova; S. V. Nemtsev; V. P. Varlamov (pp. 77-83).
Mycological analysis throughout the vegetation period of potato (Solanum tuberosum) made it possible to study in detail the structure of the micromycete community, to determine typical dominant (frequency, more than 60%), typical common (frequency, 30 to 60%), typical rare (frequency, 10 to 30%), and casual (frequency, less than 10%) species and to estimate changes in the microorganism community caused by plant protection preparations with different mechanisms of action. It was shown that, as a result of occurrence of resistant forms, synthetic preparations against fungal pathogens of potato (such as TMTD, Ridomil gold MC, and Cupricol) were only slightly more effective than biological preparations (Trichodermin and AgroChit), with the former considerably changing the natural saprophytic mycological community. An increase in the soil pool of Trichoderma harzianum as a result of application of a biological preparation based on this antagonistic fungus correlated with its effectiveness against the soil pathogen Fusarium sp., which causes root rot. A chitosan-based elicitor preparation more effectively suppressed the development of early (Alternaria sp. and Macrosporium sp.) and late (Phytophthora sp.) blighting of leaves and had a weaker effect on soil microflora.
Isolation of total RNA from baker’s yeast by T. V. Yamkovaya; V. V. Khomov; S. N. Zagrebelny; V. I. Yamkovoy (pp. 84-88).
A simple method of production of total RNA from baker’s yeast was developed. Total RNA was isolated from yeast (Saccharomyces cerevisiae) biomass using lysis with sodium dodecyl sulfate at 100°C for 40–60 min and subsequent precipitation of the target product with 3 M NaCl. The preparation obtained was characterized in detail: yield of total RNA from 1 kg of pressed yeast, 9.25 g; optical density at 260 nm of 1 mg of RNA dissolved in 1 ml of water, 20.2 U; content of the acid-soluble fraction, 2.02%; and protein content, 1.8%. Total tRNA was isolated from total RNA by fractional precipitation with ethanol followed by gel filtration.
Characteristics of monoclonal antibodies against human thyroid peroxidase for use in immunoaffinity chromatography and immunoassays by O. V. Tsyganova; E. P. Kiseleva; I. I. Vashkevich; A. G. Pryadko; O. V. Sviridov (pp. 89-96).
Two types of monoclonal antibodies (MABs) against human thyroid peroxidase (TPO) have been obtained, which interact with spatially separated conformational epitopes of the antigen (K a values are in the range 108–109 M−1). The binding site of MAB F8 is in the immunodominant region of the TPO molecule, in the vicinity of the autoantigenic determinants, whereas the epitope specific for MAB A1 lies outside this location. Both MABs retain the ability to form immune complexes after solid-phase immobilization and chemical modification with a biotin derivative. The above properties suggest that MABs A1 and F8 may be used in immunoaffinity chromatography (isolation and purification of TPO from natural sources) and immunoassays for determinations of TPO (in biological fluids) and TPO autoantibodies (in human blood serum).
The content of abscisic acid and the activities of proteinases and trypsin inhibitory proteins, in the germinating seed of common beans under water stress conditions by V. I. Domash; R. F. Protsko; V. A. Vasyuk; S. V. Shumikhin; L. V. Ermolitskaya; T. P. Sharpio (pp. 97-100).
Specific features of changes in the contents of free and bound abscisic acid (ABA) and the activities of neutral and alkaline proteinases and trypsin inhibitory proteins were determined in the embryonic axis and cotyledons of the common bean (Phaseolus vulgaris L.) after drying. The changes in ABA content, observed following the loss of 5% seed weight, were regarded as an adaptive reaction to stress, whereas the corresponding changes after the loss of 10% of the seed’s weight, was regarded as a result of a pathological disturbance of ABA metabolism. Both drying modes had a negative effect on the state of the proteinase-inhibitory system, as was apparent from the disruption of the regular inverse correlation between the activities of proteinases and serine proteinase inhibitory proteins. A comparison of the dynamics of these characteristics with the buildup of water stress demonstrates an inverse correlation between the content of free ABA and the activity of the proteinases studied. This suggests a potential inhibitory effect of this hormone on the function of the hydrolases in question in the germinating seed.
A comparative study of superoxide dismutase activity assays in Crocus sativus L. corms by F. Attar; E. Keyhani; J. Keyhani (pp. 101-106).
Superoxide dismutase catalyzes the breakdown of superoxide radical anion and provides the first line of defense against oxygen toxicity. Its vital importance has made it the subject of numerous investigations. Several assays have been proposed for the detection and quantitation of superoxide dismutase activity, but their use has remained controversial and no comparative studies have been reported. In this investigation, three commonly used methods for the measurement of superoxide dismutase activity were compared to assay the enzyme in Crocus sativus L. corm extract. The methods, based on the competition between the enzyme itself and a superoxide scavenger, involved cytochrome c reduction, nitro blue tetrazolium reduction, and pyrogallol autooxidation, respectively. Because of its accuracy, reproducibility, simplicity, and cost benefit, the latter method was preferred.
Electrophoretic study of the proteins from actinidia leaves and sex identification by R. G. Khukhunaishvili; D. I. Dzhokhadze (pp. 107-110).
The protein composition of actinidia (Actinidia L.) leaves has been studied by SDS-PAGE. Specific polypeptides in the protein pattern of male and female plants belonging to two species, A. kolomikta and A. Chinensis, were detected. The potential of biochemical protein markers for identification of plant sex is discussed.
Sorption of components from a mixture of odorants by polysaccharides of starch, chitosan, and carrageenan by T. A. Misharina; M. B. Terenina; N. I. Krikunova; M. A. Kalinchenko (pp. 111-115).
Sorption of components from a mixture of odorants in aqueous suspensions of native cornstarch, chitosan, and carrageenan was studied by the method of capillary gas-liquid chromatography. Binding was primarily effected via hydrophobic cooperative interactions. The amount of sorbed odorants depended linearly on their initial concentration in the suspension. The differences in sorption characteristics of starch and chitosan were related to the presence of amino groups in the latter polysaccharide, which contributed to an increased binding of aldehydes via polar interactions. Sorption of odorants by the sulfated polysaccharide carrageenan largely depended on the structure of odorants and properties of their functional groups. Carrageenan was potent in binding aldehydes, ketones, and esters. Alcohols were less strongly bound to this polysaccharide. Sorption of lactones and guaiacol by carrageenan was the least significant.