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Applied Biochemistry and Microbiology (v.38, #3)
Milk Angiogenin (Review) by G. S. Komolova; T. V. Fedorova (pp. 199-204).
Recent data on angiogenin, a multifunctional member of the pancreatic RNase protein superfamily, are summarized. Advances in the investigation of angiogenin structure, function, and properties are analyzed. Potentialities in natural angiogenin production from inexpensive dairy byproducts are demonstrated.
Superoxide Dismutase and Catalase Activities in Carotenoid-Synthesizing Fungi Blakeslea trispora and Neurospora crassa Fungi in Oxidative Stress by N. N. Gessler; A. V. Sokolov; V. Ya. Bykhovsky; T. A. Belozerskaya (pp. 205-209).
The addition of menadione into the medium during cultivation ofNeurospora crassa in the dark activated its constitutive superoxide dismutase. Exposure to light not only activated superoxide dismutase and catalase, but also increased the content of neurosporaxanthin. Superoxide dismutase activity in the mixed (+/–) cultures of Blakeslea trispora synthesizing β-carotene in the dark was much lower than that inNeurospora crassa. The superoxide dismutase activity and catalase activity further decreased in oxidative stress with a parallel increase in the content of β-carotene. Our results indicate that neurosporaxanthin possesses photoprotective properties in Neurospora crassa. In Blakeslea trispora (+/–) fungi, β-carotene acts as a major antioxidant during inactivation of enzymes that detoxify reactive oxygen species.
Dependence of Activities of Polysaccharide Hydrolases and Oxidases from Cerrena unicolor on the Source of Carbon and Aromatic Acids in Culture Medium by V. Elisashvili; E. Kachlishvili; M. Bakradze (pp. 210-213).
The activities of carboxymethylcellulase and xylanase in the higher basidial fungusCerrena unicolorgrown in avicel-containing medium reached 1.95 and 1.50 units per mg protein, respectively, whereas in mannitol-containing medium they ranged from 0.02 to 0.04 units per mg protein. The activity of fungal β-glucosidase depended on the carbon source in the culture medium and ranged from 2.1 units per mg protein in the presence of mannitol to 17.3 units per mg protein in the presence of avicel. In contrast to polysaccharides, easily metabolizable substrates (cellobiose, mannitol, and glucose) provided the highest rates of secretion of laccase (52.7–123.5 ncat per mg protein) and ligninase (22–106 units per mg protein). The addition of tangerine pomace (TP), a substrate enriched with aromatic compounds, to the culture medium caused an increase in the rate of biosynthesis of laccase and ligninase to 862 ncat/ ml and 557 units per ml, respectively. Aromatic compounds such as p-xylidine and veratric aldehyde increased the laccase activity of C. unicolor IBB 62 from 7.9 to 23.6 and 18.3 ncat per mg protein, respectively. Veratryl alcohol caused a sevenfold increase in the activity of Mn-dependent peroxidase in the culture medium.
Synthesis of Extracellular Chitinase by Wild-Type B-10 and Mutant M-1 Strains of Serratia marcescens by A. B. Duzhak; Z. I. Panfilova; E. A. Vasyunina (pp. 214-221).
Molecular weights of extracellular chitinases from wild-type B-10 (62, 54, 43, 38, and 21 kDa) and mutant M-1 strains of Serratia marcescens (62, 52, 43, 38, and 21 kDa) were estimated by sodium dodecyl sulfate–polyacrylamide gel electrophoresis. In the absence of chitin inductors, chitinolytic enzymes were not found in the culture liquid of B-10, whereas M-1 cells produced the chitinase complex (to 470 pU/cell). Crystalline chitin insignificantly stimulated the synthesis of chitinases with molecular weights of 62, 54, and 21 kDa by B-10 (up to 20 pU/cell), but caused oversynthesis of all chitinases by the mutant strain (up to 2600 pU/cell). Colloidal chitin induced the production of chitinases by cells of both strains. Two peaks of chitinolytic activity were observed during cultivation of strains B-10 (350 and 450 pU/cell) and M-1 (2200 and 2400 pU/cell). The first peak of cell productivity was associated with biosynthesis of the chitinase complex. The second peak was related to the synthesis of enzymes with molecular weights of 54, 43, 38, and 21 kDa (B-10) or 43, 38, and 21 kDa (M-1).
Optimization of the Medium and Cultivation Conditions of Penicillium roquefortii f39 Producing the Diketopiperazine Alkaloid Roquefortine by D. M. Boichenko; N. F. Zelenkova; M. U. Arinbasarov; T. A. Reshetilova (pp. 222-225).
We optimized the medium for cultivation of Penicillium roquefortii f39, a producer of roquefortine. In this medium, the roquefortine yield increased 1.5–2-fold. An increase in roquefortine content was associated with high biomass yield, but not with an increase in biosynthetic activity of the mycelium. Direct correlation was found between extracellular roquefortine concentration and the amount of the inoculum. The use of sucrose in the inoculum medium allowed us to increase the concentration of roquefortine during fermentation to 90 mg/l.
Secondary Antimicrobial Metabolites Produced by Thermophilic Bacillus spp. Strains VK2 and VK21 by T. Z. Esikova; Yu. V. Temirov; S. L. Sokolov; Yu. B. Alakhov (pp. 226-231).
A collection of thermophilic strains of the genus Bacillus was made. The strains were screened for antimicrobial activity. Strains VK2 and VK21 isolated from thermal springs of the Kamchatka Peninsula, and antagonistic to several gram-positive bacterial species were chosen for further investigation of antibiotics produced by them. Restriction analysis of DNA coding for 16S rRNA showed that both strains can be assigned to Bacillus licheniformis. It was shown that the lytic activity of strains VK2 and VK21 was not related to the synthesis of hydrolytic enzymes. The maximum level of antimicrobial activity in the growth medium was found to correspond to the beginning of the stationary growth phase. Addition of manganese sulfate induced sporulation and altered significantly the time course of antibiotic production in both strains. Active metabolites were extracted with n-butanol. They survived boiling for 30 min and were resistant to trypsin and chymotrypsin but were partly hydrolyzed by pronase. They were stable at a pH range of 2.0–9.0.
Riboflavin Overproduction in 4-Aminopyrazolo[3,4-d]pyrimidine-Resistant Mutants of Yeast Pichia guilliermondii by V. I. Kutsyaba; N. N. Stenchuk; D. V. Fedorovich (pp. 232-235).
More than 90 mutants resistant to the adenine analogue 4-amino-pyrazolo[3,4-d]pyrimidine (4-APP), were isolated from a wild-type strain of yeast Pichia guilliermondii. Some of the App rmutants accumulated noticeable amounts of products absorbing at 260 nm in the culture medium, probably nucleotides and their derivatives. In comparison to the parent strain, the mutant App r-27 synthesized greater amounts of xanthine and uracil suggesting the presence of defects in the regulation of de novo biosynthesis of purines and pyrimidines. The regulatory mutations rib80 and rib81 are known to cause riboflavin (RF) overproduction and derepression of synthesis of corresponding enzymes in P. guilliermondii. The mutant App r-27 was crossed to the rib81 strain. The yield of RF biosynthesis in some meiotic segregants was significantly higher than that in segregants from the diploid rib81/RIB81. Apparently,rib81 and app r mutations were combined in a single genome on the favorable genetic background. An increase in RF production was also found in strains with app r mutations induced directly in the genome of the RF oversynthesizing strain rib80 rib81. These results indicate that introduction of app r mutations into the genome of P. guilliermondii can intensify their RF overproduction.
Selection of Penicillium funiculosum Strains with High Glucose Oxidase Activity by R. V. Mikhailova; T. V. Semashko; A. G. Lobanok (pp. 236-239).
Metabolic inhibitors, riboflavin, and end products of glucose oxidation were shown to be effective for the selection ofPenicillium funiculosum mutant strains with a high glucose oxidase activity. The incidence of positive mutations was highest in clones resistant to sodium azide, riboflavin, and β-D-glucono-δ-lactone. Enzyme activity in Penicillium funiculosum mutants was studied in submerged culture. The level of glucose oxidase synthesis in seven cultures was 24–56% higher than that in the parent strain of Penicillium funiculosum NMM95.132.
Effects of p-Nitrophenol and Organophosphorous Nitroaromatic Insecticides on the Respiratory Activity of Free and Immobilized Cells of Strains C-11 and BA-11 of Pseudomonas putida by O. V. Ignatov; O. I. Guliy; I. N. Singirtsev; A. A. Shcherbakov; O. E. Makarov; V. V. Ignatov (pp. 240-246).
The possibility of using the respiratory activity (RA) of microbial cells (of strains C-11 and BA-11 of Pseudomonas putida) as an instrument for quantitative determination of organophosphorous nitroaromatic insecticides, metaphos and Sumithion, and their hydrolysis product, p-nitrophenol (PNP), has been explored. The dependences of RA on the concentrations of the three compounds were linear within the range 0.5–2.5 mM. The cells of the strain BA-11 exhibited maximum selectivity in the determination of the compounds. The RAs of microbial cells differing in the modes of immobilization (adsorption to carrier surfaces vs. incorporation into gels) have been compared. Prospects of development of the microbial cell-based sensor system for determining metaphos, Sumithion, and PNP in aqueous media are discussed.
The Nature of Melanin Pigments of Several Micro- and Macromycetes by V. G. Babitskaya; V. V. Shcherba (pp. 247-251).
New inhibitors of melanin formation by micromycetes Aspergillus carbonarius, Alternaria alternata, and Paecilomyces variotii and basidiomycetes Inonotus obliquus and Phellinus robustus were found. Precursors of melanin pigments were isolated and identified. p-Hydroxybenzoic acid was identified among the products of alkaline degradation of melanin formed by micromycetes, whereas in the case of macromycetes this was protocatechuic acid. Therefore, melanins of the former were found to belong to the dihydronaphthalene group, whereas those of the latter belong to catechols.
Changes in the Antigenic Properties of Azospirillum brasilense Lipopolysaccharide, Induced by Addition of Tris-(hydroxymethyl)-aminomethane into the Culture Medium by G. L. Burygin; L. Yu. Matora; S. Yu. Shchegolev (pp. 252-254).
Addition of tris-(hydroxymethyl)-aminomethane (Tris) into the culture medium of Azospirillum brasilense sp245 changes the antigenic properties of the lipopolysaccharide (LPS) isolated from the external membrane of the bacteria. LPS preparations from the bacteria grown in the presence of Tris have been analyzed by immunodiffusion, using monospecific antibodies. The disappearance of the precipitation band corresponding to one of the two O-specific polysaccharides of the LPS (O-PS) and changes in the electrophoretic profile have been revealed. However, only minor differences in absorption spectra of products of O-PS1 reaction with phenol/sulfuric acid have been demonstrated between the bacteria grown under standard conditions and in the presence of Tris.
Effects of Iron Compounds on the Treatment of Fat-Containing Wastewaters by V. N. Ivanov; E. V. Stabnikova; V. P. Stabnikov; I. S. Kim; A. Zubair (pp. 255-258).
Effects of iron compounds on methanogenic fermentation in water polluted with fatty acids were studied. A natural readily available source of iron applicable to biological treatment of liquid wastes was searched for. A positive effect of iron on the methanogenic fermentation of fats and their degradation products—long-chain fatty acids—in aqueous media was demonstrated. It is recommended to add iron-containing clay, as an inexpensive and easily available iron source, in amounts providing the binding of the long-chain fatty acids present in wastewaters.
Immobilization of Bacillus mucilaginosus, a Producer of Exopolysaccharides, on Chitin by G. G. Nyanikova; E. E. Kuprina; O. V. Pestova; S. V. Vodolazhskaya (pp. 259-262).
The bacteria Bacillus mucilaginosus were immobilized on chitin sorbents. Exopolysaccharides produced byB. mucilaginosus were capable of efficiently sorbing copper ions. A composite biosorbent involving the chitin derivative Khizitel with immobilized B. mucilaginosus cells at the stage of active exopolysaccharide synthesis was developed.
Production and Analytical Properties of Antibodies with High Specificity to Zearalenone by A. A. Burkin; G. P. Kononenko; N. A. Soboleva (pp. 263-268).
The time course of production, specificity, and analytical potential of antizearalenone polyclonal rabbit antibody synthesized by formaldehyde condensation and conjugated to bovine serum albumin were investigated. The relative cross-reactivities with natural analogues were: zearalenone, 100%; α-zearalenole, 0.15%; and β-zearalenole, <0.02%. With synthetic analogues: zearalanone, 31.7% and α-zearalanone, 0.12%. An enzyme immunoassay for zearalenone with a sensitivity of 0.1 ng/ml was developed on the basis of these antibodies and solid-phase conjugates homologous to the immunogen in the method of synthesis.
Changes in the Antioxidant Properties of Substituted Phenol Polydisulfides during Interaction with Human Serum Albumin by D. I. Metelitsa; A. N. Eremin (pp. 269-276).
Gallic acid polydisulfide and poly(2-aminodisulfide-4-nitrophenol) in aqueous solutions were shown to form polycomplexes with human serum albumin. This process was accompanied by considerable changes in the spectrum of protein circular dichroism recorded in distilled water in the far UV range at 20°C. Complex formation between human serum albumin and polydisulfides was followed by a marked decrease in the content of α-helices and increase in the count of antiparallel β-structures in the protein. Stable complexes containing 1.5, 2.8, and 7.7 poly(2-aminodisulfide-4-nitrophenol) molecules per human serum albumin molecule were formed in bicarbonate buffer (pH 9.0). In these complexes, the secondary protein structure underwent changes similar to those in polycomplexes of human serum albumin and polydisulfides. Gallic acid polydisulfide and poly(2-aminodisulfide-4-nitrophenol) inhibited the catalase-induced degradation of 50 mM H2O2. Complexes of human serum albumin and poly(2-aminodisulfide-4-nitrophenol) increased the catalytic activity and operational stability of catalase 1.5 and 4–7-fold, respectively. This was characterized by the effective reaction rate constant (k in, s–1). Our results indicate that complexes of human serum albumin and substituted phenol polydisulfides act as potent protectors and activators of catalase during enzymatic degradation of H2O2 at high concentrations.
The Use of Elicitors for Protection of Cultured Plants Demands Caution by O. L. Ozeretskovskaya; N. I. Vasyukova (pp. 277-279).
Hazards of the use of biogenic elicitors for inducing protective mechanisms in plants without considering the possible negative effects of the elicitors are considered.
Effects of Various Phytoimmunocorrectors on Fruit and Soft Fruit Cultures by V. A. Gudkovskii; N. Ya. Kashirskaya; E. M. Tsukanova (pp. 280-285).
Catalase activity and induction of delayed chlorophyll fluorescence were shown to be the markers of the plant native state. The dependence of reaction of the plant to exogenous elicitors, stimulators or inhibitors of the defense system, on the age, cultivar and/or species was found. Prolonged effect of the treatment with phytoimmunocorrectors was observed. The necessity of careful choice of elicitors depending on the plant state was shown.
Evaluation of the Correlation between the Content of Alkaloids and Chemical Elements in Washington Lupine (Lupinus polyphyllus Lindl.) Based on Statistical Analysis and Mathematical Simulation by G. N. Buzuk; M. Ya. Lovkova; S. M. Sokolova; Yu. V. Tyutekin (pp. 286-293).
A considerable number of linear and nonlinear correlations between concentrations of quinolizidine alkaloids and concentrations of K, Ca, Mg, Ba, Zn, Cu, Ni, and V were found in lupine seeds and leaves by using methods of correlation and regression analysis. Mathematical models of regulation of alkaloid metabolism by these chemical elements were constructed. The models of regulation were considered separately for individual plant organs.
Turbidimetric Method for Quantitative Determination of Triton X-100 with Silicotungstic Acid by L. S. Lagutina; K. F. Sholts (pp. 294-297).
The formation of Triton X-100–silicotungstic acid complex was studied. Quantitative turbidimetric determination of the detergent based on this process was suggested. This method allows us to determine the complex formation at any wavelength in the range from 350 (ε350 =15600 cm–1 M–1) to 600 nm (ε600 = 9090 cm–1 M–1). The calibration curve for Triton X-100 recorded at 350 nm is linear in the concentration range of 0 to 30 μg/ml. A sigmoid calibration curve was observed at longer wavelengths. A linear fragment of the calibration curve recorded at 600 nm was found at a concentration of Triton X-100 of about 5 μg/ml. The complex nature of calibration curves can be explained by the heterogeneity of the complex dispersion.
Determination of Maximum Permissible Concentrations of Industrial Toxicants Using the Integral Biochemical Index by V. S. Sidorov; N. N. Nemova; R. U. Vysotskaya; Yu. A. Feklov (pp. 298-302).
Effects of patented mixtures of substances, used as drilling fluids in the petroleum industry, on the activity of enzymes (cathepsin D, EC 3.4.23.5; catalase, EC 1.11.1.6; and DNase, EC 3.1.4.6) and the content of analytes (malondialdehyde, fatty acids, free and collagen-associated hydroxyproline, bile acids, and total protein) in liver, gills, muscles, gonads, and bile have been studied under aquarium conditions in mature river flounder and one-year-old salmon for the purpose of determining maximum permissible concentrations. Measuring 25–30 independent biochemical parameters per organ is sufficient for establishing a direct relationship between the concentration of an industrial toxicant and the integral biochemical index, a new characteristic defined as the ratio of the number of biochemical parameters significantly deviating from control values to the total number of the parameters measured.