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Applied Biochemistry and Microbiology (v.47, #5)
Inhibitors of proteolytic enzymes under abiotic stresses in plants (review) by V. V. Mosolov; T. A. Valueva (pp. 453-459).
Data on the role of proteolytic enzyme inhibitors in plant adaptation to various unfavorable environmental abiotic factors—water deficiency, salinization of soil, extreme temperatures, etc.—and also probable functions of proteinases inhibitors in natural plant senescense are considered.
Aerobic degradation of ethylenediaminetetraacetate (review) by E. N. Kaparullina; N. V. Doronina; Yu. A. Trotsenko (pp. 460-473).
Literature data on the influence of complexing compound ethylenediaminetetraacetate (EDTA) on environmental and ecological risks related with its application were analyzed and summarized. Methods of abiotic and biotic degradation of EDTA were systemized. Special attention was paid to microbiological degradation of EDTA was paid. Data on EDTA transport and metabolism pathways in aerobic bacteria are represented. The practical aspects of application of aerobic bacteria-destructors of EDTA in ecobiotechnology were discussed.
High-efficient renaturation of immobilized recombinant C-terminal fragment of human alpha-fetoprotein by O. A. Sharapova; M. S. Yurkova; S. M. Andronova; A. N. Fedorov; S. E. Severin; E. S. Severin (pp. 474-479).
C-terminal fragment of a human oncofetal alpha-fetoprotein (AFP) may be used in targeted cytostatics delivery to malignant cells of many tumors. AFP fragment (from 404 to 595 amino acids residues of a full-sized protein) was cloned and produced in Escherichia coli cells, BL21 strain (DE3) in the form of inclusion bodies. To obtain a functionally active protein, is it necessary to renature the protein. The renaturation procedure of the AFP third domain (rAFP3D) is considerably complicated by the fact that the protein is hydrophobic and contains a large number of S-S bonds. A renaturation technique of rAFP3D immobilized on silicic metal chelate resin has been developed. The yield of renatured C-terminal fragment was no less than 60% with purity on the order of 98%. The developed technique has been applied for the first time for hydrophobic protein with a large number of S-S bonds. The approach can be applied for efficient renaturation of other hydrophobic proteins with a large number of disulfide bonds for scientific and practical purposes.
Effect of triterpenoid glycosides on α- and β-amylase activity and total protein content in wheat seedlings by E. S. Davidyans (pp. 480-486).
Influence of the aleanolic acid glycosides from Silphium perfoliatum L. (silphioside B, C, E and G) and their progenins on the amylase activity and total protein content in wheat seedlings was studied. Treatment of the Triticum aestivum L. seeds with 1–10 μM water solutions of mono- and diglycosides (mono- and bisdesmosines) elevated the α-amylase and total amylase activities in seedlings. Silphioside E containing three glucose moieties in its molecule did not change α-amylase activity, but it did if bis-triglycoside acetylated carbohydrate (as in silphioside C). Effects of 5–10 μM solutions of the active glycosides was comparable with that of exogenous gibberellin A3 and 6-benzylaminopurine.
Changes in gene transcription and protein expression involved in the response of Agrobacterium sp. ATCC 31749 to nitrogen availability during curdlan production by L. J. Yu; J. R. Wu; Z. Z. Zheng; C. C. Lin; X. B. Zhan (pp. 487-493).
The changes in transcription of genes involved in nitrogen metabolism and curdlan biosynthesis, and total protein expression were firstly analyzed to define the responses of Agrobacterium sp. ATCC 31749 to nitrogen source availability during curdlan fermentation. The transcription of all nitrogen metabolism and regulation genes increased significantly under nitrogen limitation. The genes of carbon (exoC) and nitrogen (ntrB, ntrC, and nifR) metabolism showed distinctive transcriptional responses to nitrogen limitation. Their relative expression level was increased by 14, 9, 7 and 7-fold, respectively. Two-dimentional electrophoresis (2-DE) revealed that the expression of 14 proteins were elevated and 6 proteins were down-regulated significantly under nitrogen starvation. Furthermore, 4 proteins (GroEL, ABC transporter, Atu1730 and enoylacyl carrier protein reductase) in which the expression level changed significantly were identified. The results showed that L sp. regulates its carbon flux and nitrogen assimilation effectively for better survival.
Synthesis of 3-hydroxybutyrate-CO-4-hydroxybutyrate copolymers by hydrogen-oxidizing bacteria by T. G. Volova; N. O. Zhila; G. S. Kalacheva; V. A. Sokolenko; E. J. Sinski (pp. 494-499).
Synthesis of 3- and 4-hydroxybutyrate copolymer (3HB-co-4HB), the most promising member of the biodegradable polyhydroxyalkanoate (PHA) family, has been studied. Cultivation conditions of naturally occurring strains of hydrogen-oxidizing bacteria Ralstonia eutropha B5786 and Cupriavidus eutrophus B10646 have been optimized to ensure efficient synthesis of the 3HB-co-4HB copolymer. A set of highly pure samples of the 3HB-co-4HB copolymer with 4HB content varying from 8.7 to 24.3 mol% has been obtained. Incorporation of 4HB into the copolymer was shown to cause a more pronounced decrease in polymer crystallinity than the incorporation of 3-hydroxyvalerate or 3-hydroxyhexanoate; samples with a degree of crystallinity below 30% have been obtained. The weight average molecular mass of the 3HB-co-4HB copolymers was shown to be independent on the monomer ratio and to vary broadly (from 540 to 1110 kDa).
Synthesis of 3-hydroxybutyrate-CO-4-hydroxybutyrate copolymers by hydrogen-oxidizing bacteria by T. G. Volova; N. O. Zhila; G. S. Kalacheva; V. A. Sokolenko; E. J. Sinski (pp. 494-499).
Synthesis of 3- and 4-hydroxybutyrate copolymer (3HB-co-4HB), the most promising member of the biodegradable polyhydroxyalkanoate (PHA) family, has been studied. Cultivation conditions of naturally occurring strains of hydrogen-oxidizing bacteria Ralstonia eutropha B5786 and Cupriavidus eutrophus B10646 have been optimized to ensure efficient synthesis of the 3HB-co-4HB copolymer. A set of highly pure samples of the 3HB-co-4HB copolymer with 4HB content varying from 8.7 to 24.3 mol% has been obtained. Incorporation of 4HB into the copolymer was shown to cause a more pronounced decrease in polymer crystallinity than the incorporation of 3-hydroxyvalerate or 3-hydroxyhexanoate; samples with a degree of crystallinity below 30% have been obtained. The weight average molecular mass of the 3HB-co-4HB copolymers was shown to be independent on the monomer ratio and to vary broadly (from 540 to 1110 kDa).
Obtaining of water soluble microbial melanin and study of its some properties by A. A. Aghajanyan; R. A. Asaturian; A. A. Hambardzumyan; L. B. Sargsyan; A. S. Hovsepyan; A. H. Vardanyan; A. S. Saghyan (pp. 500-506).
The effective sorption method for melanin isolation and purification from fermentation solutions of Bacillus thuringiensis serovar galleriae K1 has been elaborated, the principle process flowsheet is presented. The identification of obtained pigment with the samples of natural and synthetic melanin was done by IR-spectroscopy, and the intensity ratio of optical absorption at 650 and 500 nm allows to refer the isolated melanin to eumelanin class. By thermal treatment it was determined, that melanin’s amorphous sediment is steady at up to 120°C) the concentration of paramagnetic centers being changed from 0.053 × 1018 spin/g (48°C) to 0.25 × 1018 spin/g (120°C). The rising of the temperature of treatment up to 210°C brings to substantial increase of the concentration of unpaired electrons, and at 280°C its sharp growth is observed. At 350°C growth stops, then sharp decrease is observed. The obtained results were confirmed by methods of IR spectroscopy and derivatographic analysis.
Methanogenic degradation of (amino)aromatic compounds by anaerobic microbial communities by Yu. V. Lin’kova; A. T. Dyakonova; M. A. Gladchenko; S. V. Kalyuzhnyi; I. B. Kotova; A. Stams; A. I. Netrusov (pp. 507-514).
degradation of a range of aromatic substrates by anaerobic microbial communities was studied. Active methanogenic microbial communities decomposing aminoaromatic acids and azo dyes into CH4 and CO2 were isolated. Products of primary conversion were found to be 2-hydroxybenzyl and benzyl alcohols gradually transforming into benzoate. It was shown that isolated microbial communities are capable of converting the initial substrates—benzyl alcohol, benzoate, salicylic acid, and azo dye Acid Orange 6—into biogas without a lag-phase but with different velocities. Aromatic and linear intermediates of biodegradation of aromatic amines by obtained enrichment cultures were determined for the first time. Selective effect of aromatic substrates on a microbial community that was expressed in decrease in diversity and gradual change of dominant morphotypes was revealed.
Selective extraction of metals from zinc concentrate by association of chemolithotrophic bacteria by N. S. Vardanyan; A. K. Vardanyan (pp. 515-519).
Ability for selective extraction of copper and zinc from zinc concentrate using association of chemolithotrophic bacteria was investigated. In the presence of bacterial association, the rate of leaching of zinc, copper, and iron was increased 3-fold, 4–5-fold, and 2-fold, respectively. The results indicate the maximum dissolution rate for zinc, then followed by copperand iron. It was revealed that addition of Fe3+ 2 g/l resulted in reduction of iron leaching and in 3-fold increase of leaching rate of copper at constant dissolution rate of mineral zinc. It is suggested that the intensification of copper leaching is connected with the activity of sulfur-oxidizing bacteria able to activate the mineral surface via elimination of passivation layer of elemental sulfur. It was concluded that sulfur-oxidizing bacteria play a significant role in copper leaching from zinc concentrate. A unique strain of mesophile sulfur-oxidizing bacteria was isolated from leaching pulp of zinc concentrate; in the perspective, it may serve as efficient candidate for performing of selective extraction of copper from zinc concentrate.
Leaching of copper ore of the Udokanskoe deposit at low temperatures by an association of acidophilic chemolithotrophic microorganisms by T. F. Kondrat’eva; T. A. Pivovarova; L. N. Krylova; V. S. Melamud; E. V. Adamov; G. I. Karavaiko (pp. 520-526).
Pure cultures of indigenous microorganisms Acidithiobacillus ferrooxidans strain TFUd, Leptospirillum ferrooxidans strain LUd, and Sulfobacillus thermotolerans strain SUd have been isolated from the oxidation zone of sulfide copper ore of the Udokanskoe deposit. Regimes of bacterial-chemical leaching of ore have been studied over a temperature range from −10 to +20°C. Effects of pH, temperature, and the presence of microorganisms on the extraction of copper have been shown. Bacterial leaching has been detected only at positive values of temperature, and has been much more active at +20 than at +4°C. The process of leaching was more active when the ore contained more hydrophilic and oxidized minerals. The possibility of copper ore leaching of the Udokanskoe deposit using sulfuric acid with pH 0.4 at negative values of temperature and applying acidophilic chemolithotrophic microorganisms at positive values of temperature and low pH values was shown.
Increase of ethanol productivity by cell-recycle fermentation of flocculating yeast by F. Z. Wang; T. Xie; M. Hui (pp. 527-531).
Using the recombinant flocculating Angel yeast F6, long-term repeated batch fermentation for ethanol production was performed and a high volumetric productivity resulted from half cells not washed and the optimum opportunity of residual glucose 20 g l−1 of last medium. The obtained highest productivity was 2.07 g l−1 h−1, which was improved by 75.4% compared with that of 1.18 g l−1 h−1 in the first batch fermentation. The ethanol concentration reached 8.4% corresponding to the yield of 0.46 g g−1. These results will contribute greatly to the industrial production of fuel ethanol using the commercial method with the flocculating yeast.
Purification and characterisation of lignin peroxidase from Pycnoporus sanguineus MTCC-137 by J. K. Sharma; M. Yadav; N. P. Singh; K. D. S. Yadav (pp. 532-537).
Extracellular secretion of lignin peroxidase from Pycnoporus sanguineus MTCC-137 in the liquid culture growth medium amended with lignin containing natural sources has been shown. The maximum secretion of lignin peroxidase has been found in the presence of saw dust. The enzyme has been purified to homogeneity from the culture filtrate of the fungus using ultrafiltration and anion exchange chromatography on DEAE-cellulose. The purified lignin peroxidase gave a single protein band in sodium dodecylsulphate polyacrylamide gel electrophoresis corresponding to the molecular mass 40 kDa. The K m, k cat and k cat/K m values of the enzyme using veratryl alcohol and H2O2 as the substrate were 61 M, 2.13 s−1, 3.5 × 104 M−1s−1 and 71 M, 2.13 s−1, 3.0 × 104 M−1 s−1 respectively at the optimum pH of 2.5. The temperature optimum of the enzyme was 25°C.
GC-MS and spectrophotometric analysis of biodegradation of new disazo dye by Trametes versicolor by H. Ardag Akdogan; A. Demircali; C. Aydemir; N. Pazarlioglu; F. Karci (pp. 538-542).
In this study; sub-tropical white rot fungi, Trametes versicolor was investigated for its ability to degrade 4-(3′-methyl-4′-(4″-nitrophenyl)azo-1′H-pyrazol-5′-ylazo)-3-methyl-1H-pyrazol-5-on in the mediums containing glucose and different concentrations of degrade dye in batch systems. This dye was synthetized at Pamukkale Universtiy of Organic Chemistry research laboratory. Samples were collected on 10 days, and was detected by Shimadzu UV-1600A spectrophotometry. Decolorization study showed that this disazo dye was removed by more than 70% in 10 days. Laccase enzyme activity was detected in samples and then last sample was analyzed by GC-MS. Metabolites weren’t showed in GC-MS result. It was concluded that T. versicolor could achieve the biodegradation of this new disazo dye.
Effect of polycyclic aromatic hydrocarbons on laccase production by white rot fungus Pleurotus ostreatus D1 by N. N. Pozdnyakova; S. V. Nikiforova; O. E. Makarov; O. V. Turkovskaya (pp. 543-548).
The effect of polycyclic aromatic hydrocarbons (PAHs) on the time course of laccase production by the fungus Pleurotus ostreatus D1 under conditions of submerged cultivation on Kirk’s medium has been studied. It has been shown that phenanthrene, fluoranthene, pyrene, and chrysene actively induce this enzyme, whereas fluorene and anthracene had a smaller effect. Addition of Mn2+ ions to cultivation medium elevates the laccase activity twofold and more in the presence of all the studied PAHs. Electrophoresis under nondenaturing conditions demonstrates induction of additional laccase forms by xenobiotics. Ligninolytic peroxidase activities are undetectable under the conditions used.
Salicylic and Jasmonic acids in regulation of the proantioxidant state in wheat leaves infected by Septoria nodorum Berk by L. G. Yarullina; N. B. Troshina; E. A. Cherepanova; E. A. Zaikina; I. V. Maksimov (pp. 549-555).
Influence of mediators of the signal systems of salicylic (SA) and jasmonic (JA) acids and their mixture on reactive oxygen species’ (ROS) (superoxide radical and O 2 ·− H2O2) generation and activity of oxidoreductases (oxalate oxidase, peroxidase and catalase) in leaves of wheat Triticum aestivum L. infected by Septoria leaf blotch pathogen Septoria nodorum Berk has been studied. Presowing treatment of seeds by SA and JA decreased the development rate of fungus on wheat leaves. SA provided earlier inductive effect on production of O 2 ·− and H2O2 compared with JA. The protective effect of the salicylic and jasmonic acids against Septoria leaf blotch pathogen was caused by activation of oxalate oxidase, induction of anion and cation peroxidases, and decrease of catalase activity. Ability of compounds to stimulate ROS in the plant tissues can be used as criteria for evaluation of immune-modulating activity of new substances for protection of the plants.
Application of standard addition for the determination of carboxypeptidase activity in Actinomucor elegans bran koji by J. Fu; L. Li; X. Q. Yang; M. J. Zhu (pp. 556-562).
Leucine carboxypeptidase (EC 3.4.16) activity in Actinomucor elegans bran koji was investigated via absorbance at 507 nm after stained by Cd-nihydrin solution, with calibration curve A, which was made by a set of known concentration standard leucine, calibration B, which was made by three sets of known concentration standard leucine solutions with the addition of three concentrations inactive crude enzyme extract, and calibration C, which was made by three sets of known concentration standard leucine solutions with the addition of three concentrations crude enzyme extract. The results indicated that application of pure amino acid standard curve was not a suitable way to determine carboxypeptidase in complicated mixture, and it probably led to overestimated carboxypeptidase activity. It was found that addition of crude exact into pure amino acid standard curve had a significant difference from pure amino acid standard curve method (p < 0.05). There was no significant enzyme activity difference (p > 0.05) between addition of active crude exact and addition of inactive crude kind, when the proper dilute multiple was used. It was concluded that the addi-tion of crude enzyme extract to the calibration was needed to eliminate the interference of free amino acids and related compounds presented in crude enzyme extract.