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Applied Biochemistry and Microbiology (v.40, #5)
Prospects for the Practical Application of Substrate-Binding Modules of Glycosyl Hydrolases by I. Yu. Volkov; N. A. Lunina; G. A. Velikodvorskaya (pp. 427-432).
The properties of substrate-binding modules of glycosyl hydrolases have been reviewed. The variation of the properties of these modules makes them promising as components of chimeric proteins, which is a rapidly developing field of biotechnology. Examples of applying substrate-binding modules of glycosyl hydrolases to the immobilization of proteins and whole cells on polysaccharides and the purification of proteins are described. Promising methods for (1) detecting various compounds using hybrids of substrate-binding modules with antibodies and (2) locating polysaccharides in live tissues are reviewed as well.
Precipitated, Coprecipitated, and Carbon–Mineral Sorbents for Isolation of Exracellular Catalase from Penicillium piceum F-648 by A. N. Eremin; M. V. Makarenko; A. P. Drozhdenyuk; I. V. Moroz; R. V. Mikhailova (pp. 433-440).
The abilities of various sorbents to adsorb catalase (CAT; EC 1.11.1.6) from filtered culture liquid (FCL) of the fungus Penicillium piceum F-648 were compared. Potassium phosphate, hydroxyapatite (HAP), and coprecipitated sorbents containing calcium phosphate and magnesium hydroxide adsorbed extracellular CAT more efficiently than aluminum oxide, aluminum phosphate, or quartz sand. The enzyme was isolated from FCL of Penicillium piceum with the use of HAP and a binary coprecipitated sorbent, Ca3(PO4)2 + Mg(OH)2, 1 : 1 (CM). The CAT(CM) sample contained the least amount of protein admixture. Its spectra had absorption maximums at 279.6, 406.8 (Soret band), 540, 585, 636, and 703 nm and negative molar ellipticity minimums at 207 and 210–214 nm. The kinetic indices of the samples (K M, V max : K M, and specific activity) were intricately dependent on the protein concentration in the reaction mixture. In dilute solutions, the K M and specific activities of CAT(CM) and CAT(HAP) equaled 667 and 137 mM; 300.9 × 104 and 30.0 × 104 U/mg protein, respectively. The effective velocity constants of inactivation of CAT(HAP), CAT(CM), and FCL in the reaction of H2O2 decomposition increased dramatically after the dilution of samples. In the infinitely dilute solution, they were 4.30 × 10–2, 6.46 × 10–2, and 1.12 × 10–2 s–1, respectively.
Effect of Pasteurization on the Activity of Proteinases in Salmon Roe by L. R. Kopylenko; T. E. Rubtsova (pp. 441-444).
We studied the dependence of activity and stability of proteolytic enzymes in salmon roe on pH and temperature. The activity of proteolytic enzymes in roe was primarily determined by proteinases. These enzymes were active at acid pH and had an optimum of 3.6. A study of subclasses of proteolytic enzymes in salmon roe and the published data suggest that the activity of proteinases may be related to the presence of aspartyl proteinases (cathepsin D). Serine proteinases and metalloenzymes were not found in roe. The activity of cysteine proteinases was low. The proposed conditions of pasteurization favored the complete inactivation of salmon roe at pH 6.0–6.4.
Chitinolytic Activity of Filamentous Fungi by A. A. Shubakov; P. S. Kucheryavykh (pp. 445-447).
The chitinolytic activity of nine species of filamentous fungi, classified with seven genera (specifically, Aspergillus, Penicillium, Trichoderma, Paecilomyces, Sporotrichum, Beaueria, and Mucor), was studied. When cultured in liquid medium containing 1% crystalline chitin, all fungi produced extracellular chitosans with activity varying from 0.2 U/mg protein (Sporotrichum olivaceum, Mucorsp., etc.) to 4.0–4.2 U/mg protein (Trichoderma lignorum, Aspergillus niger).
N-Acetyl-β-D-hexosaminidase Secreted by the Marine Fungus Phoma glomerata by N. V. Zhuravleva; P. A. Luk'yanov; M. V. Pivkin (pp. 448-453).
Among the ten strains of marine fungi studied, the mycelial fungus Phoma glomerata showed maximum potency in producing N-acetyl-β-D-glucosaminidase. The conditions for fungal growth and enzyme biosynthesis were evaluated. N-Acetyl-β-D-hexosaminidase was isolated from the culture liquid of Phoma glomerata by ion-exchange chromatography (on DEAE–cellulose and DEAE–Sephacell) and gel filtration (on Toyopearl HW-55) with a yield of 35%; the enzyme, purified 36.4-fold, had a molecular weight of 20 kDa. The homogeneity of the enzyme was confirmed by gel filtration and SDS-PAGE. Transglycosylation reactions catalyzed by the enzyme produced N-acetyl-D-glucosamine and N-acetyl-D-galactosamine with respective yields of 38 and 46%.
Effect of Carbohydrate Composition of the Cytosol of Aspergillus niger Conidia on Their Viability During Storage by V. M. Tereshina; A. V. Kovtunenko; A. S. Memorskaya; E. P. Feofilova (pp. 454-459).
It is shown that the rate of sporogenesis, the appearance of low-molecular-weight thiols, and the activation of carbohydrate synthesis in spores adversely affected the viability of Aspergillus niger conidia during storage. Conversely the prevalence of trehalose over mannitol and the absence of glycerol, erythritol, and glucose in the carbohydrate composition facilitated the viability of conidia. The data obtained are discussed with regard to the biochemical criteria that may be used to characterize the quiescent state of fungi and retaining the viability of the inoculum.
Search for Yeast Producers of Brassylic and Sebacic Fatty Acids by I. V. Ulezlo; I. S. Rogozin (pp. 460-462).
Yeast cultures belonging to the genera Candida, Torulopsis, Saccharomyces, Debaryomyces, Hansenula, Pichia, and Yarrowia, capable of synthesizing brassylic and sebacic fatty acids, were screened. Overall about 200 cultures grown in media containing decane or tridecane as a sole source of carbon were tested. On the medium with tridecane, yeasts synthesized insignificant amounts of brassylic acid. Sebacic acid was produced more intensively in the medium with n-decane. The culture Candida tropicalis, displaying the highest ability to synthesize sebacic acid, was selected.
Conversion of Androstenedione and Androstadienedione by Sterol-Degrading Bacteria by N. E. Voishvillo; V. A. Andryushina; T. S. Savinova; T. S. Stytsenko (pp. 463-469).
The composition of steroid metabolites formed during the conversion of androstenedione and androstadienedione, products of the degradation of sterol side chains by soil and mutant strains of the bacterial genera Mycobacterium and Protaminobacter, was studied. Testololactone was absent from the conversion products. This favors the idea of different cleavage pathways of steroid ring D in bacteria and fungi. Very small amounts of two new 14α-hydroxy derivatives with a cleaved B ring were isolated after the conversion of androstenedione by soil strains. It was shown that a mutant Mycobacterium smegmatis strain, as well as wild strains, could perform 14α-hydroxylation of steroids. It is suggested that cleavage of the steroid nucleus at the side of rings D and C starts with the introduction of a 14α-hydroxy group followed by dehydration.
Production of Surfactants by Rhodococcus erythropolis Strain EK-1, Grown on Hydrophilic and Hydrophobic Substrates by T. P. Pirog; T. A. Shevchuk; I. N. Voloshina; E. V. Karpenko (pp. 470-475).
The ability of Rhodococcus erythropolis strain EK-1 to produce surfactants when grown on hydrophilic (ethanol and glucose) and hydrophobic (liquid paraffins and hexadecane) substrates was studied. The strain was found to produce surfactants with emulsifying and surface-active properties. The production of surfactants depended on the composition of the nutritive medium, nature and concentration of the sources of carbon and nitrogen, and duration of cultivation. Chemically, surfactants produced by Rhodococcus erythropolis EK-1 grown on ethanol are a complex of lipids with polysaccharide–proteinaceous substances. The lipids include glycolipids (trehalose mono- and dicorynomycolates) and common lipids (cetyl alcohol, palmitic acid, methyl n-pentadecanoate, triglycerides, and mycolic acids).
Biological Properties of the Phosphorus-Mobilizing Bacillus subtilis Strain IMV V-7023 by A. A. Roi; O. N. Reva; I. K. Kurdish; V. V. Smirnov (pp. 476-481).
Biological characteristics of a new phosphate-mobilizing bacillus strain are reported. Species-level identification of the strain was performed according to morphological, cultural, and biochemical characteristics and the sequence of the 16S rRNA gene. The strain was identified as Bacillus subtilis IMV V-7023 and displayed a very high ability to mobilize phosphorus from its sparingly soluble inorganic and organic compounds and the capability of synthesizing biologically active substances; in addition, the strain essentially suppressed the growth of phytopathogenic bacteria, micromycetes, and agents causing various diseases of vegetable, cereal, leguminous, and other plants. The strain Bacillus subtilis IMV V-7023 is promising for developing bacterial preparations for crop production.
Lysozyme of the Mollusk Unio pictorum and the Sensitivity of Alkanotrophic Rhodococci to Its Effect by G. N. Solovykh; V. P. Korobov; I. V. Karnaukhova; L. M. Lemkina; E. I. Ushakova; G. M. Ustinova; V. V. Minakova (pp. 482-489).
A preparation of lysozyme from a freshwater bivalve, Unio pictorum, has been isolated by sorption to chitin, and its physicochemical properties have been studied. An assessment of the sensitivity of 48 strains of rhodococci, belonging to the species Rhodococcus rubber, R. luteus, and R. erythropolis (Specialized Collection of Alkanotrophic Microorganisms of the Institute of Ecology and Genetics of Microorganisms, Ural Division of the Russian Academy of Sciences), which were isolated from diverse natural waters, to lysozyme of the mollusk Unio pictorum demonstrated that the three species differ in their sensitivity to its effects. The high resistance of rhodococci to lysozyme is indicative of their considerable permanence in hydrobiocenoses (and, therefore, ability to maintain self-purification of microbiocenoses from hydrocarbons).
The Significance of Exometabolites in the Formation and Operation of the Soybean–Rhizobium Symbiosis by E. V. Kirichenko; L. V. Titova; S. Ya. Kots' (pp. 490-493).
The effect of various inoculates of the soybean-specific strain of nodule bacteria Bradyrhizobium japonicum 634b (unwashed cells, cells washed from the exopolysaccharide–protein complex, and cells combined with the complex) on the formation and operation of soybean–rhizobium symbiosis. It was shown that addition of the exopolysaccharide–protein complex doubled the ability of the microsymbiont to form nodules, nodule weight, and the nitrogenase activity of the nodules. Bradyrhizobium japonicum 634b cells washed from exometabolites had lower indices of symbiotic activity than their intact counterparts.
Extracellular Polymers in Callus Cultures of Fagopyrum tataricum (L.) Gaertn. with Different Morphogenic Activities: Time Courses During the Culture Cycle by N. I. Rumyantseva; A. N. Akulov; A. R. Mukhitov (pp. 494-500).
Time courses of the content of extracellular polymers (ECPs) in culture media of morphogenic and non-morphogenic calluses (MCs and NCs, respectively) of tartar buckwheat Fagopyrum tataricum (L.) Gaertn. were studied during the culture cycle. It was demonstrated that MCs secreted into the medium far more ECPs than NCs did. During the passage of MCs, two ECPs “blowouts” were observed, which preceded the formation of proembryonic cell complexes (PECCs). It is supposed that the molecules secreted might be involved in PECC recycling in MCs. The maximal content of ECPs in NCs was observed by the end of the stationary growth phase of the culture, which is presumably related to changes in the cell walls during callus aging.
Effect of Salicylic Acid on the Activity of Antioxidant Enzymes in Wheat under Conditions of Salination by A. R. Sakhabutdinova; D. R. Fatkhutdinova; F. M. Shakirova (pp. 501-505).
The effect of pretreatment with 0.05 mM salicylic acid (SA) on the activity of superoxide dismutase (SOD) and peroxidase in the roots of four-day-old seedlings of wheat (Triticum aestivum L.) was studied under conditions of salination. The level of the stress-induced accumulation of active oxygen species and, therefore, activities of SOD and peroxidase in seedlings pretreated with SA were significantly lower than in untreated seedlings, which indicates that these enzymes contribute to the protective effect of SA on plants under conditions of salination.
Changes in the Biochemical Composition, Structure, and Function of Pea Leaf Chloroplasts in Iron Deficiency and Root Anoxia by V. G. Ladygin (pp. 506-516).
A combined effect of iron deficiency and root anoxia on the biochemical composition, function, and structure of pea leaf chloroplasts was studied. It was found that the chlorosis of apical leaves in response to iron deficiency was determined by the reduction of light-harvesting complexes I and II. Under root anoxia, complexes of the reaction centers of photosystems I and II degraded first. Weak activity was preserved even in yellow and white leaves under the effect of both factors. The ultrastructure of leaf chloroplasts gradually degraded. Initially, intergranal thylakoid sites were reduced, and the longitudinal orientation of grana was disturbed. However, yellow and white leaves still retained small thylakoids and grana. It is concluded that the degrading effects of iron deficiency and root anoxia on the complex composition and leaf chloroplast structure and function are additive because of their autonomous mechanisms.
Fractional Isolation and Study of the Structure of Galactomannan from Sophora (Styphnolobium japonicum) Seeds by N. I. Smirnova; N. M. Mestechkina; V. D. Sherbukhin (pp. 517-521).
Two fractions (1 and 2) of the galactomannan from seeds of sophora (Styphnolobium japonicum) were isolated using cold and hot aqueous extraction with a total yield of 12.88%. The two fractions differed by the ratio between mannose (Man) and galactose (Gal) residues (4.8 : 1 and 5.3 : 1, respectively) and molecular weight (1190 and 1400 kDa, respectively). Aqueous solutions of these fractions were optically active ([α]D = +4.80° and –3.36°, respectively) and highly viscous ([η] 1028.8 and 1211.2 ml/g). 13C NMR spectra of both fractions were identical with respect to the number and positions of signals, which indicates that their primary structures were identical. Using chemical and spectroscopic (IR and NMR) methods, it was shown that the galactomannan has a main chain consisting of 1,4-β-D-mannopyranose, some residues of which (16 and 17% in fractions 1 and 2, respectively) are α-galactosylated at the C-6 position. Frequencies of differently substituted mannobiose blocks in the chain, calculated for fraction 1 using NMR spectroscopic data, were 0.13 for the disubstitited blocks Gal(Man–Man)Gal, 0.37 for the sum of monosubstituted blocks Gal(Man–Man) and (Man–Man)Gal, and 0.50 for the unsubstituted block Man–Man.
Interaction of the Immune System of the Organism with Saprotrophic Opportunistic Microflora and Possible Coupling of the Process with the Metabolic Status of Humans: A Scientific Discussion by L. A. Piruzyan; E. M. Mikhailovskii (pp. 522-526).
The article sets forth the concept of natural biospheric immunization of a macroorganism by opportunistic saprotrophic microflora. Immunization by opportunistic microflora and microbial control of the metabolic status (which is coupled to the immune status of the organism) may act in concert to provide immune defense. Efficient immunization requires that normal microflora be certified and the patients be phenotyped by the type and rate of xenobiotic biotransformation (via oxidation and acetylation). Data from the literature, based on which the suggested measures to stimulating the immune defense of the organism should be taken, are analyzed.
Erratum: “Carotenoids and Fatty Acids in Red Yeasts Sporobolomyces roseus and Rhodotorula glutinis” [Applied Biochemistry and Microbiology, vol. 40, no. 4, 2004, p. 392]
by P. Davoli; V. Mierau; R. W. S. Weber (pp. 529-529).