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Applied Biochemistry and Microbiology (v.41, #1)
Chitosan-based polyelectrolyte complexes: A review by A. V. Il’ina; V. P. Varlamov (pp. 5-11).
This review focuses on the formation of polyelectrolyte chitosan complexes with biologically active compounds and the prospects of use thereof. The possibility of obtaining low-molecular-weight, water-soluble batches of chitosan, which differ in their degree of acetylation, is discussed, with emphasis on their use for binding nucleic acids into complexes.
Inhibition of soybean urease by polycarbonyl compounds by E. I. Tarun; D. B. Rubinov; D. I. Metelitza (pp. 12-17).
Competitive inhibition of soybean urease was studied at 36°C in aqueous solution (pH 4.95) in the presence of polycarbonyl compounds (PCCs): oxalyldihydrazide (ODH), its polydisulfide (poly(DSODH)), three cyclic β-triketones (CTKs), and seven cyclic PCC species of differing structure. The inhibition constants of ureolysis (Ki) varied in the range 8.5–3800 µM depending on the structure of organic chelators for the nickel atom in urease. It was shown that pH variation within the range from 3.85 to 7.40 exerted a strong effect on the values of Ki of three CTKs and hydroxyurea, which was used as a reference: pH dependences of log Ki were linear in all cases and displayed a break at pH 6.0–6.5. The most effective inhibitor of ureolysis was poly(DSODH), which contained ∼28 carbonyl groups in the polymer molecule. The role of such factors as the number of carbonyl groups per PCC molecule, mutual arrangement, and reaction medium pH in the efficiency of the process of urease inhibition is discussed.
Effect of flavonoids of various structures on peroxidation of neutral lipids of animal origin by S. V. Antoshina; A. A. Selishcheva; G. M. Sorokoumova; E. A. Utkina; N. S. Degtyarev; V. I. Shvets (pp. 18-23).
The effect of flavonoids of various structures (baikalein, baikalin, quercetin, dihydroquercetin, genistein, and daidzein) on the process of formation of lipid hydroperoxides during thermoinduced autooxidation of neutral lipids of animal origin is studied. The minimum inhibitory concentration of isoflavones was found to be equal to 10-3 M. The effective inhibitory concentration of other flavonoids (except baikalin) was equal to 10-4 M. Baikalin was an effective promoter of lipid peroxidation. The antioxidant activity of the flavonoids tested was calculated, taking ionol as a reference.
Effect of carbohydrates and polyols on amide content and protein fragmentation in a lactoglobulin preparation by M. Yu. Bibov; B. F. Vachaev; I. A. Sorokina; A. I. Lukash; A. A. Sinichkin; E. A. Yagovkin (pp. 24-28).
Certain carbohydrates and polyols are used at various stages of the production of immunobiological preparations as stabilizers of biological activity, particularly in the production of lactoglobulin (against opportunistic pathogens) using membrane ultrafiltration. This study concerns the effect of these substances on changes in the amide content in proteins of this lactoglobulin. Lactoglobulin was incubated in near-physiological (0.9% NaCl, pH 5.5) 10% solutions of glucose, fructose, and sorbitol at 4 and 35°C for 7, 14, and 28 days. A lactoglobulin solution in 0.9% NaCl, pH 5.5, was used as the control. All substances studied suppressed the reduction of the amide group content of asparagine and, in contrast, increased the rate of amide group removal from glutamine residues in proteins of lactoglobulin preparations.
Hymeniacidon perleve associated bioactive bacterium Pseudomonas sp. NJ6-3-1 by Li Zheng; Xiaojun Yan; Jilin Xu; Haimin Chen; Wei Lin (pp. 29-33).
Among marine bacteria isolated from the cytotoxic sponge Hymeniacidon perleve, one strain NJ6-3-1 classified as Pseudomonas sp. showed both cytotoxic and antimicrobial activities. Fatty acid analysis indicated that the bacterial strain consists mainly of C16:1, C16:0, C18:1, C18:0, C15:0, C14:0. One unusual 9,10-cyclopropane-C17:0 fatty acid and C26:0 also constitute major components, as well as the existence of squalene, the precursor of triterpenoids. The major metabolites in the culture broth were identified as alkaloids, including diketopiperazines and indole compounds, namely 3,6-diisopropylpiperazine-2,5-dione, 3-benzyl-3-isopropylpiperazine-2,5-dione, 3,6-bis-(2-methylpropyl)-piperazine-2,5-dione, indole-3-carboxaldehyde, indole-3-carboxylic acid methyl ester, indole-3-ethanol, and quinazoline-2,4-dione.
Isolation and characterization of thermostable DNA polymerase of the hyperthermophilic archaeum Thermococcus litoralis Sh1AM by G. B. Slobodkina; N. A. Chernykh; S. A. Lopatin; A. V. Il’ina; G. E. Bannikova; W. Ankenbauer; M. A. El’darov; V. P. Varlamov; E. A. Bonch-Osmolovskaya (pp. 34-41).
Overall, 30 strains of hyperthermophilic archaea, representing seven species of the genera Thermococcus, Desulfurococcus, Thermoproteus, and Acidilobus, were tested for the presence of thermostable DNA polymerases. Thermostabilities of the polymerases varied distinctly among the strains within one species. Polymerases of five strains retained 60–100% activity upon incubation of the preparations at 95°C for 120 min. A new DNA polymerase was isolated from the strain Thermococcus litoralis Sh1AM, possessing the enzyme with the most promising properties, and characterized. Molecular weight of the enzyme is 90–100% kDa. The purified DNA polymerase preserved 50% of the initial activity upon incubation at 95°C for 120 min. The polymerase isolated displayed an associated 3’–5’ exonuclease activity. The error rate when extending a DNA strand was at least twofold lower compared with Taq polymerase. The main physicochemical and enzymatic properties of the new polymerase are similar to the known DNA polymerases of family B.
Bioconversion of phenyllactate to phenylalanine by bacteria of the genus Pseudomonas by A. V. Beloded; D. A. Paramonov; M. V. Korovina; S. A. Mulyashov; N. S. Markvichev (pp. 42-46).
The nature of phenylalanine auxotrophy in Pseudomonas sp. strain M9 was studied. A metabolic defect was found after the aromatic amino acid pathway branches from chorismate, so that the latter could not be converted to phenylpiruvate. It was shown that enzymatic activity of the strain could convert phenyllactate to phenylalanine. The reaction mechanisms were studied, and approaches to increasing the rate of the process and phenylalanine yield were proposed.
Sensitivity of various Escherichia coli strains to 2,4,6-trinitrotoluene by B. M. Kurinenko; N. A. Denivarova; G. Yu. Yakovleva (pp. 47-50).
The sensitivity of Escherichia coli strains K-12 and 055 to 2,4,6-trinitrotoluene (TNT) was found to correlate with the structural and functional properties of the outer lipoprotein membrane. The protective ability of the membrane of strain 055 is much lower than that of K-12. This is the cause of the greater sensitivity of 055 to the toxic action of TNT. High TNT concentrations (100–200 mg/l) suppressed the growth of 055, whereas K-12 grew at all TNT concentrations studied. Both strains adapted to high TNT concentrations by converting it by either nitroreduction or denitritation depending on concentration. The denitritation system of strain 055 started TNT degradation earlier than that of K-12.
Use of claydite-immobilized oil-oxidizing microbial cells for purification of water from oil by T. P. Pirog; T. A. Shevchuk; I. N. Voloshina; N. N. Gregirchak (pp. 51-55).
Oil-oxidizing bacteria were isolated from oil-polluted soil and water samples and identified as Acinetobacter calcoaceticus K-4, Nocardia vaceinii K-8, Rhodococcus erythropolis EK-1, and Mycobacterium sp. K-2. It was found that immobilization of the bacteria on an expanded clay aggregate accelerated their growth and consumption of hydrocarbon substrates. It was also found that water polluted with 100 mg/l oil could be purified with Rhodococcus erythropolis EK-1 and Nocardia vaceinii K-8 cells immobilized in this way. The dependence of the degree of water purification on its flow rate, aeration, and availability of nitrogen and phosphorus sources was determined. The efficiency of water purification from oil by immobilized Rhodococcus erythropolis EK-1 cells at high flow rates (of up to 0.68 l/h), low aeration (of 0.1 l/l per min) and an intermittent supply of 0.01% diammonium phosphate reached 99.5–99.8%.
Evaluation of substrate specificity of biosensor models based on strains degrading polycyclic aromatic compounds by A. N. Reshetilov; P. V. Iliasov; A. P. Fesay; G. V. Ivashchenko; L. A. Taranova; M. Winther-Nielsen; J. Emneus (pp. 56-62).
Models of microbial biosensors based on 11 strains of degraders of surface-active substances (SASs) and polycyclic aromatic hydrocarbons (PAHs) were studied. Substrate specificity, sensitivity, and stability of biosensor models were comparatively evaluated.
Formation of structured communities by natural and transgenic naphthalene-degrading bacteria by O. A. Mogil’naya; E. S. Krivomazova; T. V. Kargatova; T. I. Lobova; L. Yu. Popova (pp. 63-68).
This study concerns the formation of structured communities by monocultures and binary associations of Pseudomonas fluorescens transgenic strains and natural heterotrophic bacterial species in naphthalene-containing media with various osmotic pressures. It was shown that cells of P. fluorescens strain 5RL, harboring a recombinant construct in the chromosome, were more resistant to the combined action of the stress factors under study than P. fluorescens 82/pUTK21, harboring a recombinant construct within a plasmid. Natural P. fluorescens 1 strains, particularly Vibrio sp. 14, were more viable at high osmotic pressures and naphthalene concentrations. Experiments with the combined introduction of transgenic and natural bacterial strains at high osmotic pressures demonstrated the stable coexistence of bacterial associations in biofilms, independent of naphthalene concentration. Strains considered for introduction into the environment for bioremediation should be assessed with regard to their susceptibility to the combined effect of anthropogenic and natural stress factors. The design of bacterial associations for the same purpose should take into account the effect of factors important for their survival in polluted areas.
Fermentation of high-protein plant biomass by introduction of lactic acid bacteria by R. A. Shurkhno; R. G. Gareev; A. G. Abul’khanov; Sh. Z. Validov; A. M. Boronin; R. P. Naumova (pp. 69-78).
Lactic acid bacteria displaying increased ability to produce lactic acid, medium proteolytic activity, and tolerance to osmotic stress were isolated under selective conditions from phyllosphere and rhizosphere of registered and raised cultivars of legumes. Lactic fermentation of poorly ensilable leguminous plants (red clover and Caucasian goat’s rue) was performed by introduction of rifampin-resistant homofermenting representatives of the genus Lactobacillus (selected according to a set of technologically important characteristics). The results demonstrate that introduction of active local strains of lactobacteria, as well as the collection strain Lactobacillus plantarum BS933, enhances activation of ensiling and increases the quality of fodder, as assessed according to the standard criteria (a decrease in pH of the medium, the ratio of lactic acid to fatty acid homologues, and the composition of silage microflora).
Trigliceropeptides from pseudomonades: New agents for biological control of pytopathogenic fungi by S. P. Chetverikov; O. N. Loginov (pp. 79-82).
Substances of a peptide nature have been isolated from the low-molecular-weight fraction of extracellular metabolites of Pseudomonas chlororaphis (strains IB 51 and IB 6) and Pseudomonas putida (strain IB 17). These substances possess antifungal activity against a broad range of phytopathogens but lack the properties of siderophores. It has been shown by HPLC, IR, and 13C NMR spectroscopy that isolated metabolites are glycerol tripeptides with molecular weights in the range 2.8–3.0 kDa.
Production of mycophenolic acid by fungi of the genus Penicillium link by N. G. Vinokurova; N. E. Ivanushkina; G. A. Kochkina; M. U. Arinbasarov; S. M. Ozerskaya (pp. 83-86).
Out of 36 strains of fungi of the genus Penicillium, some of which were isolated from ancient permafrost, 14 strains synthesized mycophenolic acid (MPA). Maximal (over 500 mg/l) accumulation of MPA in culture liquid was observed in P. brevicompactum strains (VKM F-457, VKM F-477, and VKM F-1150). This was the first study to detect MPA in representatives of the species P. rugulosum; in three strains of this species (VKM FW-665, VKM FW-717, and VKM FW-733), the level of MPA accumulation exceeded 300 mg/l. The time course of the synthesis of MPA by P. rugulosum strain VKM FW-733 was studied. It was shown that the synthesis of this metabolite was dramatically intensified during the stationary growth phase (ten days).
Proteolytic enzymes as markers of productivity and heterosis of silkworm by I. D. Krylova; D. V. Yarygin; Yu. B. Filippovich (pp. 87-93).
A positive correlation between the activity level of cysteine proteinases in developing eggs of common silkworm moth (Bombyx mori L.), on the one hand, and a set of commercial characteristics, on the other, was found. This allows the determination of cysteine proteinase activities (pH optima of 3.0, 3.6, and 8.6) to be recommended as a biochemical test for an early prediction of potential productivity of silkworm breeds. A positive correlation between the activity level of acid cysteine proteinases in eggs of parental breeds and a set of commercial characteristics of their hybrids was detected, indicating the possibility of predicting the degree of heterosis.
Effects of natural and artificial defoliation on the content and composition of extractive substances in birch leaves by E. E. Shul’ts; S. A. Bakhvalov; V. V. Martem’yanov; T. N. Petrova; I. N. Syromyatnikova; M. M. Shakirov; G. A. Tolstikov (pp. 94-98).
Qualitative and quantitative compositions of extracts of birch (Betula pendula Roth.) leaves after natural and artificial defoliation were studied. Composition of the fraction of total lipids was determined. Over-all, 11 fatty acids were identified. Differences between the fatty acid compositions of total lipids in the trees subjected to defoliation, consisting in the increase in quantities of short-chain saturated fatty acids and trienoic acids, were detected. Nine individual compounds—six flavones, two flavanones, and one flavanonol—were isolated from the flavonoid fraction by column chromatography. It was found that the total content of extractive substances in birch leaves as well as amounts of free sterols, triterpene compounds, and flavones decreased 1 year after artificial defoliation and 1 month after depredation of 75% of birch stands by gypsy moths. On the contrary, the contents of flavanones and flavanonol increased. The assay method proposed may be used for studying the compositions of plant extracts.
Formation of phenolic compounds in various cultivars of wheat (Triticum aestivum L.) by N. V. Zagoskina; N. A. Olenichenko; Chzhou Yun’vei; E. A. Zhivukhina (pp. 99-102).
The formation of soluble phenolic compounds, including flavonols, was studied in winter (Erythrospermum , Lutescens 230, and R 47-28) and spring cultivars (Lada) of wheat (Triticum aestivum L.). The contents of soluble phenolic compounds and flavonols were 1.8–2.6 and 0.5–1.3 mg/g fresh weight, respectively. These results illustrate the similarity of phenol metabolism in leaves of winter and spring wheat cultivars. The exception was the cultivar R 47-28 that accumulated the maximum amount of phenolic compounds (e.g., flavonols). In this cultivar the ratio of flavonols reached 50% of total soluble phenol content. In other cultivars, this parameter did not exceed 25–35%. The data indicate that the cultivar R 47-28 differs from other wheat cultivars in metabolism of phenolic compounds. The observed differences are probably related to genetic modifications of the cultivar R 47-28 during selection.
Role of L-phenylalanine ammonia Lyase in the induced resistance and susceptibility of sotato plants by N. G. Gerasimova; S. M. Pridvorova; O. L. Ozeretskovskaya (pp. 103-105).
Biogenic elicitors (chitosan and its complex with salicylic acid) and an immunosuppressor (laminarin) were shown to increase the activity of L-phenylalanine ammonia lyase (EC 4.3.1.5) and protein synthesis in potato tubers. Laminarin did not decrease L-phenylalanine ammonia lyase activity. It is unlikely that the activity of this enzyme serves as a criterion for the induced resistance.
Protein markers of plant traits in breeding spring wheat for grain yield and quality by E. V. Berezovskaya; V. A. Trufanov; T. N. Mitrofanova; L. S. Kazmiruk (pp. 106-111).
A comparative study of the composition of gliadin proteins in grains of different-quality wheat cultivars Rollo and Drott and four forms of the hybrids F9 and F10 obtained by crossing these cultivars has been performed. The grain yield of ears, quality of flour, dough, and gluten were compared. Groups of genetically linked gliadin components, controlled by chromosomes 1 and 6 of homologous groups, have been identified as protein markers of selectively valuable plant traits.