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Applied Biochemistry and Microbiology (v.44, #2)
Organization of metabolic pathways and molecular-genetic mechanisms of xenobiotic degradation in microorganisms: A review by V. G. Khomenkov; A. B. Shevelev; V. G. Zhukov; N. A. Zagustina; A. M. Bezborodov; V. O. Popov (pp. 117-135).
Contemporary data on the mechanism of biodegradation of aromatic hydrocarbons and biodegradation genes (genomic organization and pathways of evolution) in diverse groups of microorganisms have been reviewed. Studies of this problem are topical, in view of the need in identification and construction of new strains degrading xenobiotics, particularly those halogenated. For this reason, emphasis is placed on specific features of explored metabolic pathways that can be used for constructing new enzymatic systems not present in nature. Sections on the mechanisms of genomic rearrangements involving biodegradation determinants are presented from the same standpoint. Part of the review is devoted to analyzing methods used for studying the population dynamics of bacterial communities involved in xenobiotic degradation in natural biotopes or industrial waste disposal plants. Particular attention is given to methods of gene systematics.
Organization of metabolic pathways and molecular-genetic mechanisms of xenobiotic degradation in microorganisms: A review by V. G. Khomenkov; A. B. Shevelev; V. G. Zhukov; N. A. Zagustina; A. M. Bezborodov; V. O. Popov (pp. 117-135).
Contemporary data on the mechanism of biodegradation of aromatic hydrocarbons and biodegradation genes (genomic organization and pathways of evolution) in diverse groups of microorganisms have been reviewed. Studies of this problem are topical, in view of the need in identification and construction of new strains degrading xenobiotics, particularly those halogenated. For this reason, emphasis is placed on specific features of explored metabolic pathways that can be used for constructing new enzymatic systems not present in nature. Sections on the mechanisms of genomic rearrangements involving biodegradation determinants are presented from the same standpoint. Part of the review is devoted to analyzing methods used for studying the population dynamics of bacterial communities involved in xenobiotic degradation in natural biotopes or industrial waste disposal plants. Particular attention is given to methods of gene systematics.
Bioactive natural products from endophytes: A review by B. Guo; Y. Wang; X. Sun; K. Tang (pp. 136-142).
Endophytes, microorganisms that reside in the internal tissues of living plants without causing any immediate overt negative effects, have been found in every plant species examined to date and recognized as potential sources of novel natural products for exploitation in medicine, agriculture, and industry with more and more bioactive natural products isolated from the microorganisms. In this review, we focus mainly on bioactive natural products from endophytic microorganisms by their different functional roles. The prospect and facing problems of isolating natural products from endophytes are also discussed.
Bioactive natural products from endophytes: A review by B. Guo; Y. Wang; X. Sun; K. Tang (pp. 136-142).
Endophytes, microorganisms that reside in the internal tissues of living plants without causing any immediate overt negative effects, have been found in every plant species examined to date and recognized as potential sources of novel natural products for exploitation in medicine, agriculture, and industry with more and more bioactive natural products isolated from the microorganisms. In this review, we focus mainly on bioactive natural products from endophytic microorganisms by their different functional roles. The prospect and facing problems of isolating natural products from endophytes are also discussed.
Changes in physicochemical properties of proteins, caused by modification with alkylhydroxybenzenes by Yu. A. Nikolaev; N. G. Loiko; I. Yu. Stepanenko; E. F. Shanenko; E. I. Martirosova; V. K. Plakunov; A. N. Kozlova; I. A. Borzenkov; O. A. Korotina; D. S. Rodin; Yu. F. Krupyanskii; G. I. El-Registan (pp. 143-150).
Kinetic characteristics of model enzymes and physicochemical properties of globular proteins modified by chemical analogues of low-molecular-weight microbial autoregulators (alkylhydroxybenzenes, AHBs) have been studied. C7 and C12 AHB homologues were used, differing in the length of the alkyl radical and the capacity for weak physicochemical interactions. Both homologues affected the degree of protein swelling, viscosity, and the degree of hydrophobicity. The effects depended on the structure of AHBs, their concentration, and pH of the solution, which likely reflects changes in the charge of the protein globule and its solvate cover. Variations of hydrophobicity indices of AHB-modified enzymes (trypsin and lysozyme) were coupled to changes in the catalytic activity. The values of K M, measured for the enzymes within both AHB complexes, did not change, whereas V max increased (in the case of C7 complexes) or decreased (C12 complexes). Possible molecular mechanisms of changes in the physicochemical and catalytic parameters of enzymatically active proteins, induced by modification with structurally distinct AHBs, are described, with emphasis on targeted regulation of functional activity.
Changes in physicochemical properties of proteins, caused by modification with alkylhydroxybenzenes by Yu. A. Nikolaev; N. G. Loiko; I. Yu. Stepanenko; E. F. Shanenko; E. I. Martirosova; V. K. Plakunov; A. N. Kozlova; I. A. Borzenkov; O. A. Korotina; D. S. Rodin; Yu. F. Krupyanskii; G. I. El-Registan (pp. 143-150).
Kinetic characteristics of model enzymes and physicochemical properties of globular proteins modified by chemical analogues of low-molecular-weight microbial autoregulators (alkylhydroxybenzenes, AHBs) have been studied. C7 and C12 AHB homologues were used, differing in the length of the alkyl radical and the capacity for weak physicochemical interactions. Both homologues affected the degree of protein swelling, viscosity, and the degree of hydrophobicity. The effects depended on the structure of AHBs, their concentration, and pH of the solution, which likely reflects changes in the charge of the protein globule and its solvate cover. Variations of hydrophobicity indices of AHB-modified enzymes (trypsin and lysozyme) were coupled to changes in the catalytic activity. The values of K M, measured for the enzymes within both AHB complexes, did not change, whereas V max increased (in the case of C7 complexes) or decreased (C12 complexes). Possible molecular mechanisms of changes in the physicochemical and catalytic parameters of enzymatically active proteins, induced by modification with structurally distinct AHBs, are described, with emphasis on targeted regulation of functional activity.
2D [1H,13C] NMR study of carbon fluxes during glucose utilization by Escherichia coli MG1655 by A. D. Kivero; E. V. Bocharov; V. G. Doroshenko; A. G. Sobol; M. A. Dubinnyi; A. S. Arseniev (pp. 151-157).
Carbon fluxes through main pathways of glucose utilization in Escherichia coli cells-glycolysis, pentose phosphate pathway (PPP), and Enther-Doudoroff pathway (EDP)—were studied. Their ratios were analyzed in E. coli strains MG1655, MG1655Δ(edd-eda), MG1655Δ(zwf, edd-eda), and MG1655Δ(pgi, edd-eda). It was shown that the carbon flux through glycolysis was the main route of glucose utilization, averaging ca. 80%. Inactivation of EDP did not affect growth parameters. Nevertheless, it altered carbon fluxes through the tricarboxylic acid cycles and energy metabolism in the cell. Inactivation of PPP decreased growth rate to a lesser degree than glycolysis inactivation.
2D [1H,13C] NMR study of carbon fluxes during glucose utilization by Escherichia coli MG1655 by A. D. Kivero; E. V. Bocharov; V. G. Doroshenko; A. G. Sobol; M. A. Dubinnyi; A. S. Arseniev (pp. 151-157).
Carbon fluxes through main pathways of glucose utilization in Escherichia coli cells-glycolysis, pentose phosphate pathway (PPP), and Enther-Doudoroff pathway (EDP)—were studied. Their ratios were analyzed in E. coli strains MG1655, MG1655Δ(edd-eda), MG1655Δ(zwf, edd-eda), and MG1655Δ(pgi, edd-eda). It was shown that the carbon flux through glycolysis was the main route of glucose utilization, averaging ca. 80%. Inactivation of EDP did not affect growth parameters. Nevertheless, it altered carbon fluxes through the tricarboxylic acid cycles and energy metabolism in the cell. Inactivation of PPP decreased growth rate to a lesser degree than glycolysis inactivation.
Reactivating effect of Escherichia coli exometabolites on UV-irradiated cells by L. I. Vorob’eva; E. Yu. Khodzhaev; G. M. Ponomareva (pp. 158-161).
Wild-type and mutant (AB 1157 and K-12) strains of Escherichia coli were shown to synthesize the logarithmic growth phase, exometabolites reactivating UV-irradiated cells of producer strains. The exometabolites of the strain K-12 were of protein nature and had a molecular weight of no more than 10 kDa. The reactivating activity of these exometabolites was inversely related to bacterial survival and slightly increased under the influence of stress factors. The reactivating factor of Luteococcus casei had a cross-reactivating and protective effect on UV-irradiated cells of E. coli strain K-12. Due to activation of the reactivating factor after UV irradiation and heating, the cross-protective effect increased more than threefold. The reactivating effect remained unchanged under these conditions. The protein exometabolites of E. coli did not induce cross-stress response in L. casei.
Reactivating effect of Escherichia coli exometabolites on UV-irradiated cells by L. I. Vorob’eva; E. Yu. Khodzhaev; G. M. Ponomareva (pp. 158-161).
Wild-type and mutant (AB 1157 and K-12) strains of Escherichia coli were shown to synthesize the logarithmic growth phase, exometabolites reactivating UV-irradiated cells of producer strains. The exometabolites of the strain K-12 were of protein nature and had a molecular weight of no more than 10 kDa. The reactivating activity of these exometabolites was inversely related to bacterial survival and slightly increased under the influence of stress factors. The reactivating factor of Luteococcus casei had a cross-reactivating and protective effect on UV-irradiated cells of E. coli strain K-12. Due to activation of the reactivating factor after UV irradiation and heating, the cross-protective effect increased more than threefold. The reactivating effect remained unchanged under these conditions. The protein exometabolites of E. coli did not induce cross-stress response in L. casei.
Synthesis of 2-chloro-2′-deoxyadenosine by microbiological transglycosylation using a recombinant Escherichia coli strain by S. A. Taran; K. N. Verevkina; T. Z. Esikova; S. A. Feofanov; A. I. Miroshnikov (pp. 162-166).
Cladribine (2-chloro-2′-deoxyadenosine) was synthesized using intact cells of the recombinant Escherichia coli strain producing Geobacillus stearothermophilus B-2194 thermostable purine-nucleoside phosphorylase II (EC 2.4.2.1). Use of the cells containing this thermostable enzyme allowed the process to be conducted at a temperature of 70°C, which provided the maximal concentrations of sparingly soluble substrates. The best results were obtained with 2-chloroadenine as a modified base. The highest yield of the target 2-chloro-2′-deoxyadenosine (up to 95% in the case of deoxyguanosine) was reached when using 2′-deoxypurines as donors of deoxyribose. Use of thymidine for these purposes required its considerable molar excess over 2-chloroadenine (up to 6:1), which is connected with a nonoptimal amount of endogenous thymidine phosphorylase, necessary for synthesis of deoxyribose-1-phosphate, in the transglycosylation reaction.
Synthesis of 2-chloro-2′-deoxyadenosine by microbiological transglycosylation using a recombinant Escherichia coli strain by S. A. Taran; K. N. Verevkina; T. Z. Esikova; S. A. Feofanov; A. I. Miroshnikov (pp. 162-166).
Cladribine (2-chloro-2′-deoxyadenosine) was synthesized using intact cells of the recombinant Escherichia coli strain producing Geobacillus stearothermophilus B-2194 thermostable purine-nucleoside phosphorylase II (EC 2.4.2.1). Use of the cells containing this thermostable enzyme allowed the process to be conducted at a temperature of 70°C, which provided the maximal concentrations of sparingly soluble substrates. The best results were obtained with 2-chloroadenine as a modified base. The highest yield of the target 2-chloro-2′-deoxyadenosine (up to 95% in the case of deoxyguanosine) was reached when using 2′-deoxypurines as donors of deoxyribose. Use of thymidine for these purposes required its considerable molar excess over 2-chloroadenine (up to 6:1), which is connected with a nonoptimal amount of endogenous thymidine phosphorylase, necessary for synthesis of deoxyribose-1-phosphate, in the transglycosylation reaction.
Expression and purification of soluble B lymphocyte stimulator from recombinant Escherichia coli by Q. R. Guo; W. Y. Tong; D. Z. Wei; X. Y. Tao (pp. 167-173).
In this work, the expression conditions of fusion protein thioredoxin (Trx)-soluble B lymphocyte stimulator (sBLyS) in a shake flask and bioreactor from the recombinant Escherichia coli BL21 (DE3) with a pET system encoding the fusion protein gene of Trx-sBLyS and the purification method of the sBLyS were optimized to effectively obtain the bioactive protein sBLyS with a high purity. A yield of about 250 mg Trx-sBLyS/g DWC (1686 mg Trx-sBLyS/L) and expression level of about 38.5% in soluble Trx-sBLyS were obtained in a 30-1 bioreactor after optimization of the fermentation conditions. After the completion of the optimized purification procedure in order of affinity chromatography, enzymatic cleavage with enterokinase and DEAE ion exchange chromatography, about 200 mg sBLyS per liter fermentation broth was obtained with a purity of about 95% and a yield of near 30%, respectively. Furthermore, the molecular weight (MW) and the isoelectric point (pl) of the purified sBLyS were determined by 2-D gel electrophoresis and SDS-PAGE analysis and estimated to be over 16 kDa and about pH 4.15, respectively. In addition, the bioactivities of the soluble Trx-sBLyS in fermentation broth and the purified sBLyS were tested by two kinds of analytical methods of bioactivity. The good fermentation yield and the satisified, purified sBLyS product with high purity, yield and bioactivity demonstrated the sBLyS production procedure was promising in industry.
Expression and purification of soluble B lymphocyte stimulator from recombinant Escherichia coli by Q. R. Guo; W. Y. Tong; D. Z. Wei; X. Y. Tao (pp. 167-173).
In this work, the expression conditions of fusion protein thioredoxin (Trx)-soluble B lymphocyte stimulator (sBLyS) in a shake flask and bioreactor from the recombinant Escherichia coli BL21 (DE3) with a pET system encoding the fusion protein gene of Trx-sBLyS and the purification method of the sBLyS were optimized to effectively obtain the bioactive protein sBLyS with a high purity. A yield of about 250 mg Trx-sBLyS/g DWC (1686 mg Trx-sBLyS/L) and expression level of about 38.5% in soluble Trx-sBLyS were obtained in a 30-1 bioreactor after optimization of the fermentation conditions. After the completion of the optimized purification procedure in order of affinity chromatography, enzymatic cleavage with enterokinase and DEAE ion exchange chromatography, about 200 mg sBLyS per liter fermentation broth was obtained with a purity of about 95% and a yield of near 30%, respectively. Furthermore, the molecular weight (MW) and the isoelectric point (pl) of the purified sBLyS were determined by 2-D gel electrophoresis and SDS-PAGE analysis and estimated to be over 16 kDa and about pH 4.15, respectively. In addition, the bioactivities of the soluble Trx-sBLyS in fermentation broth and the purified sBLyS were tested by two kinds of analytical methods of bioactivity. The good fermentation yield and the satisified, purified sBLyS product with high purity, yield and bioactivity demonstrated the sBLyS production procedure was promising in industry.
Glucose isomerase activity in suspensions of Arthrobacter nicotianae cells and adsorption immobilization of the microorganisms on inorganic carriers by G. A. Kovalenko; L. V. Perminova; T. G. Terent’eva; L. I. Sapunova; A. G. Lobanok; T. V. Chuenko; N. A. Rudina; E. I. Chernyak (pp. 174-181).
Kinetics of monosaccharide isomerization has been studied in suspensions of intact, non-growing Arthrobacter nicotianae cells. Under the conditions of the study, glucose and fructose were isomerized at the same maximum rate of 700 μmol/min per 1 g dried cells, which increased with temperature (the dependence was linear at 60–80°C). The proposed means of adsorption immobilization of A. nicotianae cells involve inorganic carriers differing in macrostructure, chemical nature, and surface characteristics. Biocatalysts obtained by adsorbing the cells of A. nicotianae on carbon-containing foamed ceramics in the coarse of submerged cultivation were relatively stable and retained original activity (catalysis of monosaccharide isomerization) throughout 14 h of use at 70°C. Maximum glucose isomerase activity (2 μmol/min per 1 g) was observed with biocatalysts prepared by adsorption of non-growing A. nicotianae cells to the macroporous carbon-mineral carrier Sapropel and subsequent drying of the cell suspension together with the carrier.
Glucose isomerase activity in suspensions of Arthrobacter nicotianae cells and adsorption immobilization of the microorganisms on inorganic carriers by G. A. Kovalenko; L. V. Perminova; T. G. Terent’eva; L. I. Sapunova; A. G. Lobanok; T. V. Chuenko; N. A. Rudina; E. I. Chernyak (pp. 174-181).
Kinetics of monosaccharide isomerization has been studied in suspensions of intact, non-growing Arthrobacter nicotianae cells. Under the conditions of the study, glucose and fructose were isomerized at the same maximum rate of 700 μmol/min per 1 g dried cells, which increased with temperature (the dependence was linear at 60–80°C). The proposed means of adsorption immobilization of A. nicotianae cells involve inorganic carriers differing in macrostructure, chemical nature, and surface characteristics. Biocatalysts obtained by adsorbing the cells of A. nicotianae on carbon-containing foamed ceramics in the coarse of submerged cultivation were relatively stable and retained original activity (catalysis of monosaccharide isomerization) throughout 14 h of use at 70°C. Maximum glucose isomerase activity (2 μmol/min per 1 g) was observed with biocatalysts prepared by adsorption of non-growing A. nicotianae cells to the macroporous carbon-mineral carrier Sapropel and subsequent drying of the cell suspension together with the carrier.
Growth of Methylosinus trichosporium OB3b on methane and poly-β-hydroxybutyrate biosynthesis by N. V. Doronina; V. A. Ezhov; Yu. A. Trotsenko (pp. 182-185).
Optimal conditions for batch cultivation of the obligate methanotroph Methylosinus trichosporium OB3b on methane without superatmospheric pressure were chosen. The yield of absolutely dry biomass after 120 h of growth reached 20 g/l. This biomass contained 30% poly-β-hydroxybutyrate (PHB) with molecular weight 300 kDa. The growth process included the stages of biomass growth and PHB biosynthesis. The latter stage occurred under nitrogen-deficiency conditions. It was accompanied by an increase in the activity of PHB biosynthesis enzymes (β-ketothiolase, acetoacetyl-CoA reductase, and PHB synthase) and the main NAD(P)H producer, methylenetetrahydromethanopterin dehydrogenase. The activity of PHB depolymerase increased insignificantly.
Growth of Methylosinus trichosporium OB3b on methane and poly-β-hydroxybutyrate biosynthesis by N. V. Doronina; V. A. Ezhov; Yu. A. Trotsenko (pp. 182-185).
Optimal conditions for batch cultivation of the obligate methanotroph Methylosinus trichosporium OB3b on methane without superatmospheric pressure were chosen. The yield of absolutely dry biomass after 120 h of growth reached 20 g/l. This biomass contained 30% poly-β-hydroxybutyrate (PHB) with molecular weight 300 kDa. The growth process included the stages of biomass growth and PHB biosynthesis. The latter stage occurred under nitrogen-deficiency conditions. It was accompanied by an increase in the activity of PHB biosynthesis enzymes (β-ketothiolase, acetoacetyl-CoA reductase, and PHB synthase) and the main NAD(P)H producer, methylenetetrahydromethanopterin dehydrogenase. The activity of PHB depolymerase increased insignificantly.
Surfactant production by the Rhodococcus erythropolis sH-5 bacterium grown on various carbon sources by I. N. Gogotov; R. S. Khodakov (pp. 186-191).
It has been shown that the Rhodococcus erythropolis sH-5 strain can produce surfactants associated and not associated with the cell wall. Their content depends on medium composition, the nature of the carbon source, and oxygen supply. The highest biosurfactant (bioSF) yield is achieved by growing R. erythropolis sH-5 in medium with 2% kerosene at neutral pH. It has been found that the bioSF yield and emulsification index for various hydrocarbons depend on the kind of the nitrogen source used by the bacterium, increasing with replacement of KNO3 by NaNO3. The yields of biomass and bioSF in R. erythropolis depend on growth temperatures (max at 30°C) but not on water quality (bidistillate, catholyte, or anolyte). It has been found that sH-5 produces more cell-associated bioSF than extracellular species.
Surfactant production by the Rhodococcus erythropolis sH-5 bacterium grown on various carbon sources by I. N. Gogotov; R. S. Khodakov (pp. 186-191).
It has been shown that the Rhodococcus erythropolis sH-5 strain can produce surfactants associated and not associated with the cell wall. Their content depends on medium composition, the nature of the carbon source, and oxygen supply. The highest biosurfactant (bioSF) yield is achieved by growing R. erythropolis sH-5 in medium with 2% kerosene at neutral pH. It has been found that the bioSF yield and emulsification index for various hydrocarbons depend on the kind of the nitrogen source used by the bacterium, increasing with replacement of KNO3 by NaNO3. The yields of biomass and bioSF in R. erythropolis depend on growth temperatures (max at 30°C) but not on water quality (bidistillate, catholyte, or anolyte). It has been found that sH-5 produces more cell-associated bioSF than extracellular species.
Microbiological corrosion of aluminum alloys by V. F. Smirnov; D. V. Belov; T. N. Sokolova; O. V. Kuzina; V. R. Kartashov (pp. 192-196).
Biological corrosion of AD0 quality aluminum and aluminum-based construction materials (alloys V65, D16, and D16T) was studied. Thirteen microscopic fungus species and six bacterial species proved to be able to attack aluminum and its alloys. It was found that biocorrosion of metals by microscopic fungi and bacteria was mediated by certain exometabolites. Experiments on biocorrosion of the materials by the microscopic fungus Alternaria alternata, the most active biodegrader, demonstrated that the micromycete attack started with the appearance of exudate with pH 8–9 on end faces of the samples.
Microbiological corrosion of aluminum alloys by V. F. Smirnov; D. V. Belov; T. N. Sokolova; O. V. Kuzina; V. R. Kartashov (pp. 192-196).
Biological corrosion of AD0 quality aluminum and aluminum-based construction materials (alloys V65, D16, and D16T) was studied. Thirteen microscopic fungus species and six bacterial species proved to be able to attack aluminum and its alloys. It was found that biocorrosion of metals by microscopic fungi and bacteria was mediated by certain exometabolites. Experiments on biocorrosion of the materials by the microscopic fungus Alternaria alternata, the most active biodegrader, demonstrated that the micromycete attack started with the appearance of exudate with pH 8–9 on end faces of the samples.
Mutant Yarrowia lipolytica strains producing citric acid from glucose by T. V. Finogenova; I. F. Puntus; S. V. Kamzolova; Yu. N. Lunina; S. E. Monastyrskaya; I. G. Morgunov; A. M. Boronin (pp. 197-202).
The possibility of obtaining mutant yeasts Yarrowia lipolytica VKM Y-2373 with increased ability to synthesize citric acid from glucose by using UV irradiation and N-methyl-N’-nitro-N-nitrosoguanidine was studied. Of 1500 colonies of the Y. lipolytica treated with either UV or N-methyl-N’-nitro-N-nitrosoguanidine, three mutants were selected that displayed higher (by 23%) biosynthetic ability as compared with the initial strain. Additionally, three mutants were selected from 1000 colonies of the Y. lipolytica exposed to a combined action of UV and N-methyl-N’-nitro-N-nitrosoguanidine; their biosynthetic activity exceeded that of the initial strain by 43.9%. The selective media with citrate and acetate were developed for a rapid selection of mutants as well as the express methods for the detection of active citric acid producers on the solid media with chalk and bromocresol containing a limiting concentration of amine nitrogen and an excess of glucose.
Mutant Yarrowia lipolytica strains producing citric acid from glucose by T. V. Finogenova; I. F. Puntus; S. V. Kamzolova; Yu. N. Lunina; S. E. Monastyrskaya; I. G. Morgunov; A. M. Boronin (pp. 197-202).
The possibility of obtaining mutant yeasts Yarrowia lipolytica VKM Y-2373 with increased ability to synthesize citric acid from glucose by using UV irradiation and N-methyl-N’-nitro-N-nitrosoguanidine was studied. Of 1500 colonies of the Y. lipolytica treated with either UV or N-methyl-N’-nitro-N-nitrosoguanidine, three mutants were selected that displayed higher (by 23%) biosynthetic ability as compared with the initial strain. Additionally, three mutants were selected from 1000 colonies of the Y. lipolytica exposed to a combined action of UV and N-methyl-N’-nitro-N-nitrosoguanidine; their biosynthetic activity exceeded that of the initial strain by 43.9%. The selective media with citrate and acetate were developed for a rapid selection of mutants as well as the express methods for the detection of active citric acid producers on the solid media with chalk and bromocresol containing a limiting concentration of amine nitrogen and an excess of glucose.
An endophytic Neurospora sp. from Nothapodytes foetida producing camptothecin by S. Rehman; A. S. Shawl; A. Kour; R. Andrabi; P. Sudan; P. Sultan; V. Verma; G. N. Qazi (pp. 203-209).
The medicinal plant, Nothapodytes foetida, contains a number of important alkaloids like camptothecin (an anticancer drug molecule), but its concentration is less to meet the existing demand of this important molecule, in an effort for accessible availability of camptothecin. An endophyte (designated ZP5SE) was isolated from the seed of Nothapodytes foetida and was examined as a potential source of anticancer drug lead compound, i.e., camptothecin, when grown in Sabouraud liquid culture media under shake flask conditions. The presence of an anticancer compound (camptothecin) in this fungus was confirmed by chromatographic and spectroscopic methods in comparison with authentic camptothecin. Isolated endophyte (Neurospora crassa) producing camptothecin may become an easily accessible source for the production of a precursor anticancer drug molecule in the future at a large scale.
An endophytic Neurospora sp. from Nothapodytes foetida producing camptothecin by S. Rehman; A. S. Shawl; A. Kour; R. Andrabi; P. Sudan; P. Sultan; V. Verma; G. N. Qazi (pp. 203-209).
The medicinal plant, Nothapodytes foetida, contains a number of important alkaloids like camptothecin (an anticancer drug molecule), but its concentration is less to meet the existing demand of this important molecule, in an effort for accessible availability of camptothecin. An endophyte (designated ZP5SE) was isolated from the seed of Nothapodytes foetida and was examined as a potential source of anticancer drug lead compound, i.e., camptothecin, when grown in Sabouraud liquid culture media under shake flask conditions. The presence of an anticancer compound (camptothecin) in this fungus was confirmed by chromatographic and spectroscopic methods in comparison with authentic camptothecin. Isolated endophyte (Neurospora crassa) producing camptothecin may become an easily accessible source for the production of a precursor anticancer drug molecule in the future at a large scale.
Diversity and specific composition of microscopic fungi on synthetic polymeric materials by A. V. Kurakov; S. A. Gevorkyan; V. B. Goginyan; S. M. Ozerskaya (pp. 210-212).
We summarized experimental data on species diversity of fungi decomposing synthetic polymeric materials. Most of the fungi were anamorphs of the phylum Ascomycota, class Ascomycetes (231 species and 85 genera). Teleomorphs of ascomycetes were represented by 18 species and 7 genera. We revealed a smaller number of fungi belonging to the phylum Zygomycota, class Zygomycetes (31 species and 15 genera), or the phylum Basidiomycota, class Basidiomycetes (5 species and 5 genera). The specific composition of fungi was assessed on polymeric materials of various classes.
Diversity and specific composition of microscopic fungi on synthetic polymeric materials by A. V. Kurakov; S. A. Gevorkyan; V. B. Goginyan; S. M. Ozerskaya (pp. 210-212).
We summarized experimental data on species diversity of fungi decomposing synthetic polymeric materials. Most of the fungi were anamorphs of the phylum Ascomycota, class Ascomycetes (231 species and 85 genera). Teleomorphs of ascomycetes were represented by 18 species and 7 genera. We revealed a smaller number of fungi belonging to the phylum Zygomycota, class Zygomycetes (31 species and 15 genera), or the phylum Basidiomycota, class Basidiomycetes (5 species and 5 genera). The specific composition of fungi was assessed on polymeric materials of various classes.
Activation of elicitor defensive properties by systemic signal molecules during the interaction between potato and the late blight agent by N. I. Vasyukova; G. I. Chalenko; N. G. Gerasimova; T. A. Valueva; O. L. Ozeretskovskaya (pp. 213-217).
The elicitor arachidonic acid in combination with jasmonic acid (JA) induced a higher level of defense against the late blight agent in potato (Solanum tuberosum L.) tissues than in combination with salicylic acid (SA). On the contrary, the elicitor chitosan displayed a higher inductive effect in combination with SA as compared with JA. The optimal concentrations of tested compounds were selected for designing the compositions activating wound repair, induction of proteinase inhibitors, and resistance to the biotrophic pathogen Phytophthora infestans (Mont.) de Bary. It was demonstrated that the compositions of elicitor and systemic signal molecules provided a faster spreading of an inducing effect in the potato tissues.
Activation of elicitor defensive properties by systemic signal molecules during the interaction between potato and the late blight agent by N. I. Vasyukova; G. I. Chalenko; N. G. Gerasimova; T. A. Valueva; O. L. Ozeretskovskaya (pp. 213-217).
The elicitor arachidonic acid in combination with jasmonic acid (JA) induced a higher level of defense against the late blight agent in potato (Solanum tuberosum L.) tissues than in combination with salicylic acid (SA). On the contrary, the elicitor chitosan displayed a higher inductive effect in combination with SA as compared with JA. The optimal concentrations of tested compounds were selected for designing the compositions activating wound repair, induction of proteinase inhibitors, and resistance to the biotrophic pathogen Phytophthora infestans (Mont.) de Bary. It was demonstrated that the compositions of elicitor and systemic signal molecules provided a faster spreading of an inducing effect in the potato tissues.
RNA isolation from the ribonucleoproteins fixed with formaldehyde by A. S. Voronina; E. S. Pshennikova (pp. 218-222).
A method for isolating RNA from the polyribosomes and informosomes fixed with formaldehyde was developed. The ribonucleoproteins were obtained by centrifugation in CsCl density gradient. It has been demonstrated that this method makes it possible to obtain full-sized rRNA and mRNA appropriate for molecular hybridization. We succeeded in amplifying 150-nucleotide sequences of individual mRNA and demonstrating the applicability of these RNA preparations for synthesis of labeled probes for RNA arrays. The method proposed is recommended for the search for untranslated mRNA and the study of the changes in translation of individual proteins during early ontogenesis and various pathologies.
RNA isolation from the ribonucleoproteins fixed with formaldehyde by A. S. Voronina; E. S. Pshennikova (pp. 218-222).
A method for isolating RNA from the polyribosomes and informosomes fixed with formaldehyde was developed. The ribonucleoproteins were obtained by centrifugation in CsCl density gradient. It has been demonstrated that this method makes it possible to obtain full-sized rRNA and mRNA appropriate for molecular hybridization. We succeeded in amplifying 150-nucleotide sequences of individual mRNA and demonstrating the applicability of these RNA preparations for synthesis of labeled probes for RNA arrays. The method proposed is recommended for the search for untranslated mRNA and the study of the changes in translation of individual proteins during early ontogenesis and various pathologies.
Biodegradable polymeric derivatives of polypeptide drugs for targeting by L. I. Valuev; G. A. Sytov; I. M. Shanazarova; I. L. Valuev; Yu. A. Talyzenkov; N. A. Plate (pp. 223-225).
Relatively short polymer chains with lower critical solution temperatures were immobilized on protein macromolecules to obtain biodegradable polymeric derivatives of proteins (including those for heat-inactivated targeting of polypeptide drugs). Addition of a derivative to a multicomponent biological system and heating of the target to a temperature in excess of the lower critical solution temperature was followed by the carrier release into a separate phase and the transportation of the bound protein to the target. The protein molecule served as a biodegradable region and was progressively hydrolyzed, with the formation of low-molecular-weight fragments. These fragments were readily eliminated from the organism. The physiological activity of immobilized serum albumin was independent of the number of attached chains in the polymer carrier (the constant of bilirubin binding equaled 108 M−1). The biodegradation of synthetic systems, caused by α-chymotrypsin, was also studied. The more polymer chains were attached to serum albumin, the greater was the resistance of the protein to enzymatic hydrolysis.
Biodegradable polymeric derivatives of polypeptide drugs for targeting by L. I. Valuev; G. A. Sytov; I. M. Shanazarova; I. L. Valuev; Yu. A. Talyzenkov; N. A. Plate (pp. 223-225).
Relatively short polymer chains with lower critical solution temperatures were immobilized on protein macromolecules to obtain biodegradable polymeric derivatives of proteins (including those for heat-inactivated targeting of polypeptide drugs). Addition of a derivative to a multicomponent biological system and heating of the target to a temperature in excess of the lower critical solution temperature was followed by the carrier release into a separate phase and the transportation of the bound protein to the target. The protein molecule served as a biodegradable region and was progressively hydrolyzed, with the formation of low-molecular-weight fragments. These fragments were readily eliminated from the organism. The physiological activity of immobilized serum albumin was independent of the number of attached chains in the polymer carrier (the constant of bilirubin binding equaled 108 M−1). The biodegradation of synthetic systems, caused by α-chymotrypsin, was also studied. The more polymer chains were attached to serum albumin, the greater was the resistance of the protein to enzymatic hydrolysis.
Preparation of chitosan microparticles and study of their interaction with interferon by A. V. Il’ina; A. A. Gubaidullina; A. I. Melent’ev; V. P. Varlamov (pp. 226-230).
Chitosan with viscosity average molecular weights of 340, 281, 199, 137, and 42 kDa was used to prepare microparticles by precipitation coacervation. Acid and enzymatic hydrolysis yielded chitosan samples with a deacetylation degree of 0.85 ± 0.03. The chitosan microparticles were 0.85–1.7 μm in size and had a ζ-potential of 30.7−38.6±0.1 mV. Testing the microparticles for toxicity showed that they caused no death of animals. Interaction of recombinant α-2 interferon with the microparticles was studied by sorption from solutions. The maximum adsorption efficiency of interferon was 88% and the capacity of microparticles was 11.8–12.7 μg/mg.
Preparation of chitosan microparticles and study of their interaction with interferon by A. V. Il’ina; A. A. Gubaidullina; A. I. Melent’ev; V. P. Varlamov (pp. 226-230).
Chitosan with viscosity average molecular weights of 340, 281, 199, 137, and 42 kDa was used to prepare microparticles by precipitation coacervation. Acid and enzymatic hydrolysis yielded chitosan samples with a deacetylation degree of 0.85 ± 0.03. The chitosan microparticles were 0.85–1.7 μm in size and had a ζ-potential of 30.7−38.6±0.1 mV. Testing the microparticles for toxicity showed that they caused no death of animals. Interaction of recombinant α-2 interferon with the microparticles was studied by sorption from solutions. The maximum adsorption efficiency of interferon was 88% and the capacity of microparticles was 11.8–12.7 μg/mg.
A. E. Kuznetsov and N. B. Gradova, scientific foundations of ecobiotechnology (textbook), Moscow: Mir, 2006, 504 pp.
by V. V. Biryukov (pp. 231-232).
A. E. Kuznetsov and N. B. Gradova, scientific foundations of ecobiotechnology (textbook), Moscow: Mir, 2006, 504 pp.
by V. V. Biryukov (pp. 231-232).