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Applied Biochemistry and Microbiology (v.36, #1)
A polyclonal antiserum to the noncatalytic part of cellobiohydrolase I fromTrichoderma reesei by M. L. Gerner; G. V. Leontyeva; I. G. Romenskaya; M. S. Melnick; M. L. Rabinovich (pp. 1-3).
A specific antiserum to the noncatalytic part of cellobiohydrolase I fromTrichoderma reesei was obtained by exhaustion of rabbit antiserum to the native enzyme with its catalytic domain prepared by papain treatment of cellobiohydrolase I tightly adsorbed onto microcrystalline cellulose.
Preparative dephosphorylation of calcium salts of 2′(3″)-mononucleotides with extracellular phosphatase fromSpicaria violacea by V. N. Barai; I. A. Severina; T. A. Kukharskaya; A. I. Zinchenko (pp. 4-7).
The properties of the phosphatase present in the culture liquid ofSpicaria violacea were investigated. Based on these results, a method for preparative dephosphorylation of calcium salts of 2′(3′)-mononucleotides was proposed. A 96–98% yield was achieved at a substrate concentration of 100 mg/ml. Mild quantitative hydrolysis of RNA to nucleosides can be performed by RNA digestion to mononucleotides with Ca2+ followed by the proposed dephosphorylation procedure.
Restriction endonucleases from various bacterial strains displaying an ice-nucleating activity by A. V. Pertsev; M. M. Den’mukhametov; A. G. Anoshkin; E. V. Ariskina; I. A. Berezin; A. S. Solonin; N. P. Kuz’min (pp. 8-10).
Six strains containing site-specific endonucleases II were selected from a collection of 45 ice-nucleating bacterial strains isolated from rhizosphere of plants growing in various geographical regions. EndonucleasesPft211I,Psp8I, andPsp23I were isolated and purified from twoPseudomonas sp. strains and aPseudomonas fluorescens strain. Restriction endonucleasesPfl2lI andPsp23I were shown to recognize and cleave the DNA nucleotide sequence 5′-CTGCA↓G-3′. Endonuclease Psp81 recognized and cleaved the DNA nucleotide sequence 5′-G↓GATCC-3′. These endonucleases were found to be true isoschizomers of PstI andBamHI, respectively.
The use of13C/12C isotope abundance ratio for characterization of the origin of ethyl alcohol by A. M. Zyakun; V. N. Zakharchenko; A. I. Kudryavtseva; V. P. Peshenko; L. P. Mashkina; V. M. Voznyak; Yu. V. Shurukhin (pp. 11-14).
The carbon isotope composition of ethyl alcohol produced during alcohol fermentation depended on the substrate used and was characterized by the value of δ13C equal to −24.7 ± 0.8%. (wheat grain), −22 ± 0.1%. (rye grain), −22 ± 0.5%. (products of wood hydrolysis), −15.3 ±0.3%. (maize grain) and −10 ± 0.1%. (sugar cane). The isotope composition of carbon of ethyl alcohol obtained during catalytic hydroxylation of ethylene has a δ13C of −30.6 ± 0.3%.. The possibility of quantitative determination of specific components in mixtures of ethanol samples with various isotope compositions (chemical synthesis and alcohol fermentation of raw material from C3 or C4 plants) was shown.
Adaptation ofRhodococcus rhodochrous M8, a producer of acrylamide, to changes in ammonium concentration in the growth medium by O. B. Astaurova; T. E. Leonova; I. N. Polyakova; I. V. Sineokaya; V. K. Gordeev; A. S. Yanenko (pp. 15-18).
The mechanism of adaptation of the acrylamide producing strainRhodococcus rhodochrous M8 to changes in ammonium concentrations in the medium was studied. An increase in the content of ammonium in the medium changed the activity of glutamine synthetase (GS) (EC 6.3.1.2) and glutamine dehydrogenase (GD) (EC 1.4.1.4), the enzymes of ammonium assimilation, as well as the activities of enzymes responsible for nitrile utilization: nitrile hydratase (EC 4.2.1.84) and amidase (EC 3.5.1.4). This also inhibited the activation of GS induced by phosphodiesterase (EC 3.1.4.1 ). Increases in the activities of nitrile hydratase and amidase and resistance of these enzymes to ammonium were observed in mutant ofR. rhodichrous resistant to phosphotricine, an inhibitor of GS. An important role of GS in the mechanism of adaptation is suggested.
Enzymatic utilization of cotton oil soap stock by K. D. Davranov; K. A. Gulyamova; B. Kh. Alimova; N. M. Turapova (pp. 19-22).
Enzymatic hydrolysis of neutral fat of cotton oil soap stock with a nonspecific lipase produced byOospora lactis F-500 was designed. The culture liquid and a preparation of enzyme obtained by precipitation with isopropanol from a filtrate of the culture liquid were used. Utilization of cotton oil soap stock as the only source of carbon during cultivation of the fungus was studied. The rate of hydrolysis of soap stock fat strongly depended on the way of biological conversion of cotton oil soap stock. The most effective utilization was observed during cultivation of the fungus in the medium containing soap stock.
Optimization of conditions for submerged cultivation of the basidiomyceteCoriolus hirsutus, a producer of extracellular laccase by O. V. Koroleva; E. V. Stepanova; V. P. Gavrilova; N. S. Yakovleva; E. O. Landesman; A. I. Yaropolov (pp. 23-28).
The effects of various factors on the biosynthesis of extracellular laccase (EC 1.14.18.1) by the basidiomyceteCoriolus hirsutus (Wulf.:Fr.) Quel. no. 072 during submerged cultivation were examined. Optimal parameters for cultivation in a fermenter of 101 were determined: temperature, 28°C; stirrer rotation speed, 160 rpm; and the inoculum volume, 15% of the working volume of the fermenter. The filtrate contained peroxidase, laccase, and phenol oxidase activities and displayed a high thermal stability.
Effects of stress on the composition of yeast lipids by M. V. Zalashko; G. A. Salokhina; I. F. Koroleva (pp. 29-32).
Pigmented(Rhodotorula glutinis) and nonpigmented(Lipomyces starkeyi) yeasts were studied. Exogenous Stressors (UV irradiation and methylene blue) were shown to change the composition of yeast lipids (especially the ratio of unsaturated fatty acids) and to increase the content of lipid peroxidation products formed (particularly in nonpigmented yeasts). In carotene-synthesizing yeasts, these Stressors decreased the amount of carotenoids produced and did not affect the ratio between carotenoid pigments (β-carotene, torulene, and torularhodin).
Formation of pyrogallol ether during oxidative destruction of oak lignin with air oxygen by M. G. Bezhuashvili; N. N. Eradze; L. A. Mudjiri (pp. 33-35).
Formation of pyrogallol ether during thermal oxidation of oak (Quercus iberica L.) lignin in the presence of air oxygen was investigated. A model reaction demonstrated that the substance identified by us as pyrogallol ether (1,2-dioxy-3-methoxybenzene) is derived from syringic aldehyde.
Interaction of albumins and hemin with aromatic antioxidants: A spectrophotometric and fluorometric study by O. B. Rus’; A. V. Puchkaev; A. I. Ivanov; D. I. Metelitsa (pp. 36-45).
Difference spectrophotometry and fluorescence quenching of human and bovine serum albumins were used to determine their association constants(K a) with hemin in buffered physiological saline (pH 7.4) supplemented with 2% dimethylsulfoxide or in 40% aqueous dimethylformamide (pH 7.4).K a values depended on the medium, the extent of albumin delipidation, and on the method of determination. The formation of hemin complexes witho-phenylenediamine, tetramethylbenzidine, gallic acid, its polydisulfide, and two substituted di-tert-butyl pyrocatechols was studied by difference spectrophotometry in the same media;K a values for the complexes were calculated and compared to each other. The formation of complexes of these aromatic ligands with albumins was studied fluorometrically;K a values were of order of ∼105 M−1 and decreased with the ligand hydrophobicity.
Obtaining a high-activity strain capable of producing the antistaphylococcal antibiotic batumin by V. V. Smirnov; L. N. Churkina; V. I. Perepnikhatka; N. S. Mukvich; A. D. Garagulya; E. A. Kiprianova; A. N. Kravets; S. A. Dovzhenko (pp. 46-49).
The use of chemical and UV-induced mutageneses allowed us to increase the biosynthetic activity of the strain capable of producing new antistaphylococcal antibiotic, batumin. The strain ofPseudomonas batumici N17 producing 87–100 mg batumin per liter culture liquid was selected. Its activity was 3.5-5 times higher than the activity of the most potent natural strain.P. batumici N17 was shown to be stable in relation to the synthesis of batumin.
Storage of the strains of industrial microorganisms, entrapped in polymer matrices by A. Yu. Fedorov; E. V. Volchenko; I. N. Singirtsev; V. I. Korzhenevich; G. M. Snub (pp. 50-57).
Our study of the techniques of long-term storage of the biomass of various strains of microorganisms, which cause breakdown or transformation of synthetic organic compounds, demonstrates that desiccated agar beads with immobilized microbial cells can be used for this purpose. In addition, the cells can be stored in desiccated matrices of agar or polyvinyl alcohol, coating synthetic cords. Such dry biocatalysts may be used for quick starting of bioreactors and in other biotechnological processes. The technique is applicable to storage of various strains ofPseudomonas, Corynebacterium, Rhodococcus, and, to a lesser extent, Enterobacteriaceae.
α-Chymotrypsin immobilized on ferromagnetic particles coated with titanium oxide: Production and catalytic characterization by A. F. Izmailov; M. V. Kiselev; A. V. Vakurov; A. K. Gladilin; A. V. Levashov (pp. 58-62).
Immobilization of α-chymotrypsin on magnetic particles with stable coat with titanium oxides as a main constituent allowed the biocatalytic system to be quickly and qualitatively separated into the components after completion of the enzymatic reaction. X-ray phase analysis demonstrated that the coat of magnetic particles is composed mainly of titanium dioxide in brookite modification. The maximal capacity of the particles amounted to 0.3 mg protein/mg particles. It was demonstrated that the reaction catalyzed by immobilized α-chymotrypsin proceeds in a kinetic mechanism due to a high dispersion of the ferromagnetic particles. The catalytic constant (25 s−1) andK M (0.17 mM) for the immobilized enzyme for the hydrolysis of N-acetyl-L-tyrosine ethyl ester are comparable to the corresponding characteristics for the free enzyme.
Reduction of nitro-substituted compounds by native and immobilizedEscherichia coli cells by T. I. Davidenko; G. I. Bondarenko (pp. 63-68).
Reduction of nitro-substituted compounds, 1,4-benzodiazepine-2-ones, dibenzo[b,f]-1,4-diaz-epines, quinolones, and quinoxalinones, byEscherichia coli cells was studied. Physicochemical methods demonstrated the formation of corresponding amines. 4-(p-Nitrophenyl)-1H-6-R-quinolones-2 were nor reduced byEscherichia coli cells. Regiospecific reduction of 2,4-dinitro-5H-l l-(p-R-phenyl)-dibenzo[b,f]-1,4-diazepines and 4-(2′-R-3′,5′-dinitro)-benzoyl-3,4-dihydroquinoxalinones-2 was shown to result in the formation of 2-nitro-4-amino-5H-11-(p-R-phenyl)-dibenzo[b,f]-1,4-diazepines and 4-(2′-R-3′-nitro-5′-amino)-benzoyl-3,4-dihydroquinoxalinones-2, respectively. Methods for microbiological reduction of nitro compounds and immobilization ofEscherichia coli cells into carrageenan and its modified forms were elaborated.
Effect of various methods of immobilization on the stability of a microbial biosensor for surfactants based onPseudomonas rathonis T by I. N. Semenchuk; L. A. Taranova; A. A. Kalenyuk; P. V. Il’yasov; A. N. Reshetilov (pp. 69-72).
The operating and storage stability of a receptor element of an amperometric biosensor based on thePseudomonas rathonis strain T capable of degrading surfactants was tested. Microbial cells were immobilized by incorporation in gels (agar, agarose, and calcium-alginate), polyvinyl alcohol membrane, adhesion to Chromatographic paper GF/A, or by cross-linking induced by glutaric aldehyde. Incorporation of microbial cells in agar gel provides long-standing conservation of their activity and viability during measurements of high concentrations of surfactants and allows the receptor element of the biosensor to be rapidly recovered after measurements.
Immobilization of cells by entrapping in aubasidan by V. A. Abelyan (pp. 73-75).
A new technique of immobilization of microbial cells by entrapping in aubasidan, a microbial polysaccharide, was developed. This technique was applied to three cultures:Erwinia aroidea, Pseudomonas sp., andAlcaligenes faecalis, the producers of aspartase and L-aspartate β-decarboxylase. The new method is effective. After immobilization, microbial cells retained 79–91% of their initial enzymatic activity.
Thiol oxidase and disulfide reductase activities of wheatTriticum aestivum L. caryopsis and its technological quality by V. A. Trufanov; S. V. Kichatinova; A. T. Kazartseva; A. V. Permyakov (pp. 76-79).
Activities of oxygen-dependent thiol: O2 oxidoreductase (EC 1.8.3.2) and glutathione-dependent thiol: protein-disulfide oxidoreductase (EC 1.8.4.2) as well as technological value of seven soft spring wheat cultivars grown on different soil under contrasting climatic conditions (Krasnodar krai and Irkutsk oblast) were studied. It was found that the ratio of these enzymatic activities correlated positively with dough physical properties and flour bread-baking quality.
An enzyme immunoassay system for aflatoxin B1 by A. A. Burkin; G. P. Kononenko; N. A. Soboleva; E. V. Zotova (pp. 80-84).
Indirect enzyme immunoassay based on immobilized conjugate of aflatoxin B1 carboxymethyloxime with bovine serum albumin and polyclonal rabbit antibodies allows determining aflatoxin B1 with a low relative cross-reactivity against aflatoxin B2, G1, G2, M1 B2a, and G2a and sterigmatocystin (15.5, 15.5, 1.7, 1.0, 0.03, 0.03 and 0.01%, respectively) with a sensitivity of 0.04 ng per well or 4.0 ng per ml organic solvent.
Effects of exogenous folic acid on the yield and amino acid content of the seed ofPisum sativum L. andHordeum vulgare L. by L. N. Stakhova; L. F. Stakhov; V. G. Ladygin (pp. 85-89).
Effects of exogenous folic acid (FA) on the productivity ofPisum sativum L. andHordeum vulgare L. have been studied. After flowering, the plants were treated with optimum concentration of FA (25 mg per 1 water). This treatment increased the weight of the seeds by 17–19% (samplings of 1000 pcs were compared), whereas the yield became 26–29% higher. Amino acid analysis revealed a notable increase in the content of folate-dependent amino acids (e.g., glutamate, glycin, and methionine). Analysis of total folate content demonstrated that tetrahydrofolic coenzymes were significantly increased in experimental seeds. Treatment of the plants with exogenous FA increased both the content of chlorophyll in the leaves and their continuance of function. The results obtained led to the conclusion that FA treatment increases the productivity of pea and barley, by affecting the yield, weight, and quality of the seed.
Production of the medicinal and prophylactic preparation enterobifidin usingBifidobacterium adolescentis MS-42 by G. I. Novik; N. I. Astapovich; Zh. N. Bogdanovskaya; N. E. Ryabaya (pp. 90-95).
Production of Enterobifidin includes the stages of preparation of culture media, reparation of lyophilizedBifidobacterium adolescentis MS-42 culture, preparation of starters, cultivation of bacteria in fermenters, biomass conservation, and its biological control. The preparation contains physiologically active bifidobacterium cells with high activities of growth(μ = 0.7 h−1,g = 1.0 h) and acid formation (titratable acidity is ∼120–140°T; acetate concentration, 0.50–0.75%; and lactate concentration, 0.33–0.50%). The antagonistic activity of these bacteria towardsEscherichia coli 08,E. coli 086,E. coli 015,E. coli 0115, andE. coli 0101 amounts to 98.2; toProteus vulgaris 102, to 87.2; andStaphylococcus aureus 209p, to 83.2%. The bifidobacteria (with a titer of ∼109 CFU/ml) remained viable for two to five months.