[Auxin synthesis by the higher fungus Lentinus edodes (Berk.) Sing in the presence of low concentrations of indole compounds].

The auxin formation in a submerged culture of the xylotrophic basidiomycete Lentinus edodes (Berk.) Sing (Lentinula edodes (Berk.) Pegler) (shiitake) is studied. Biologically active substances of an indole nature are identified, "the effect of small doses" of which lies in not only the stimulation of growth of the mycelium (indole-3-acetic acid, 2 x 10(-7)-2 x 10(-4) g/l), but also in the induction of tryptophan-independent paths of auxin biosynthesis. The above-mentioned path is realized in the presence of exogenous indole (1 x 10(-3)-1 x 10(-4) g/l), as well as while inducing the biosynthesis of indole-3-acetic acid by its microadditives (1 x 10(-5)-1 x 10(-8) g/l), and is accompanied by the formation of anthranilic acid (up to 1.5 mg/l). Induction of the generative development stage ofshiitake by indole derivatives is revealed. It was found that among the studied compounds only indoleacetamide at a concentration of an order of x 10(-4) g/l in the culture fluid of L. edodes had a pronounced stimulatory effect on the formation of shiitake's brown mycelial film.

[Effect of polycyclic aromatic hydrocarbons on laccase production by white rot fungus Pleurotus ostreatus D1].

The effect of polycyclic aromatic hydrocarbons (PAHs) on the dynamics of laccase production by the fungus Pleurotus ostreatus D1 under conditions of submerged cultivation on Kirk's medium has been studied. It has been shown that phenanthrene, fluoranthene, pyrene, and chrysene actively induce this enzyme, whereas fluorene and anthrecene had a smaller effect. Addition of Mn2+ ions to cultivation medium elevates the laccase activity twofold and more in the presence of all the studied PAHs. Electrophoresis under nondenaturing conditions demonstrates induction of additional laccase species by xenobiotics. Ligninolytic peroxidase activities are undetectable under the conditions used.

[Characterization of an extracellular glycolipid from Lentinus edodes (Berk.) Sing [Lentinula edodes (Berk.) Pegler]].

Submerged mycelium of a xylotrophic basidiomycete Lentinus edodes produces an extracellular glycolipid, S3, associated with a lectin. Galactose glycan residue, as well as the lipid pool composition, which includes nonhydroxylated short-chain fatty acids, is uncommon for basidiomycetes. The glycolipid consists of D-galactopyranose (15% of S3 contains galactose sulfate) acylated by octadecanoic and nonadecanoic fatty acid residues (28 and 72%, respectively). The glycolipid structure and composition are confirmed by physicochemical analysis. The glycolipid is assumed to be a regulator of lectin activity.

[Oil-oxidizing potential of associative rhizobacteria of the genus Azospirillum].

The oil-oxidizing potential of associative rhizobacteria of the genus Azospirillum was studied under laboratory conditions. After screening, A. brasilense strain SR80 was chosen for further investigation. The strain was capable of degrading 56.5% of crude oil (added in a concentration of 1%) over 14 days in a medium containing malate as an additional source of carbon and energy. Studies of associative properties showed that the strain had positive chemotaxis to wheat root exudates, colonized wheat roots, and produced indolyl-3-acetic acid. The synthesis of indolyl-3-acetic acid was not inhibited by oil. Under hydroponic conditions, crude oil stimulated growth of A. brasilense SR80, which promoted development of the wheat root system in the presence of oil and enhanced the level of oil degradation by the plant-microbial association.

[Microbial degradation of mustard gas reaction masses: isolation and selection of degradative microorganisms, analysis of organic components of reaction masses and their biodegradation]. / Mikrobiologicheskaia degradatsiia reaktsionnykh mass iprita: vydelenie i selektsiia mikroorganizmov-destruktorov, analiz organicheskikh komponentov reaktsionnykh mass i ikh biodestruktsiia.

Bacterial strains growing in medium with mustard gas reaction masses (RM) as carbon sources were obtained. Growth cessation in the above medium was caused by the exhaustion of bioutilizable substrates, first of all monoethanolamine (MEA) and ethyleneglycol (EG), rather than by the accumulation of toxic metabolites in the culture liquid or in the cells. The main RM components, 1,4-perhydrothiazines (PHT), formed in the course of chemical detoxication of mustard gas, were identified and analyzed. The predominant component of PHT mixture was N-(2-hydroxyethyl)-2-methyl-1,4-perhydrothiazine hydrochloride. Concentrations of all the PHT decreased by 50% in the course of culture growth; their destruction was a result of microbial metabolism.

[Effect of cultivation parameters on the composition of extracellular polysaccharide containing substances in bacterium Azospirillum brasilense]. / Issledovanie vliianiia uslovii vyrashchivaniia bakterii Azospirillum brasilense na sostav vnekletochnykh polisakharidsoderzhashchikh materialov.

Maintenance of pH 7.0 during the fermentation period favors accumulation of high-molecular polysaccharide-containing components, the so-called lipopolysaccharide-protein and polysaccharide-lipid complexes, in the capsules and culture medium. Increased pH of the culture medium to 8.0 reduced the period of exponential growth and the yield of polysaccharide-containing complexes as compared to the optimal conditions. Maintenance of pH 5.5 suppressed the culture growth and polysaccharide production. The polysaccharide-lipid complexes obtained when pH was stabilized at the level of 7.0-8.0 had a relatively low molecular weight and contained only acidic polysaccharides. The use of potassium gluconate instead of sodium malate as a source of carbon in the culture medium changed the polysaccharide composition and increased the content of glucosamine, which increased the attraction of polysaccharides to wheat germ agglutinin. Prolongation of Azospirillum cultivation to five days introduced new glucose-containing polysaccharide components in the capsule.

Determination of organophosphorus aromatic nitro insecticides and p-nitrophenol by microbial-cell respiratory activity.

We examined the possibility of measuring the organophosphorus aromatic nitro insecticides metaphos and sumithion as well as their hydrolysis product p-nitrophenol (PNP) by the specific respiratory activity (SRA) of Pseudomonas putida C-11, P. putida BA-11, and Acinetobacter calcoaceticum A-122. The plots of cellular SRA against the two insecticides and PNP were linear over the ranges of 0.5-2.5 microM for P. putida C-11 and BA-11 and 0.5-1.0 microM for A. calcoaceticum A-122. P. putida BA-11 showed the greatest respiratory-response selectivity in the determination of the test substrates. We made comparison studies of the SRA of cells immobilised by two methods: carrier-surface adsorption and inclusion in various gels. We discuss the feasibility of developing a microbial sensor system for the determination of metaphos, sumithion, and PNP in aqueous media.

[Features of lipogenesis of basidiomycetes Pleurotus ostreatus and Flammulina velutipes in cultures on various media]. / Osobennosti lipogeneza bazidiomitsetov Pleurotus ostreatus i Flammulina velutipes pri kul'tivirovanii na razlichnykh sredakh.

The compositions of free fatty acids (FA) in the mycelia of oyster cap (Pleurotus ostreatus (Jacq. ex Fr.) Kumm.) and honey mushroom (Flammulina velutipes (Curt. ex Fr.) Sing.) and the effect of mycelium cultivation conditions on the composition and proportions of individual FA were investigated. Palmitic and linoleic acids were found to be major acids produced by P. ostreatus growing on solid agar medium and in a submerged culture with a synthetic medium. The composition of minor FA in P. ostreatus was dependent on cultivation conditions. Surface cultivation of its mycelium yielded pentadecanoic, octadecenoic, and stearic acids. Submerged cultivation additionally yielded undecanoic, myristic, hexadecenoic, and lignoceric acids. The composition of free FA in F. velutipes showed no significant differences from that of P. ostreatus. Variation in the C/N ratio in the cultivation medium affected both the FA composition in P. ostreatus and F. velutipes and the relationship between saturated and unsaturated FA.

[Effects of p-nitrophenol and organophosphorous nitroaromatic insecticides on the respiratory activity of free and immobilized cells of strains S-11 and BA-11 of Pseudomonas putida]. / Respiratornaia aktivnost' svobodnykh i immobilizovannykh kletok Pseudomonas putida shtammov S-11 i BA-11 po otnosheniiu k p-nitrofenolu i fosfoorganicheskim nitroaromaticheskim insektitsidam.

The possibility of using the respiratory activity (RA) of microbial cells (of strains S-11 and BA-11 of Pseudomonas putida) as an instrument for quantitative determination of organophosphorous nitroaromatic insecticides, metaphors 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 microM. The cells of the strain BA-11 exhibited maximum selectivity in the determination of the compounds. The RA 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 metaphors, sumithion, and PNP in aqueous media are discussed.

[Destruction of chlorinated derivatives of phenol: ortho-chlorophenol, para-chlorophenol, and 2,4-dichlorophenoxyacetic acid by bacteria communities in anaerobic sludge]. / Destruktsiia khlorproizvodnykh fenola: orto-chlorfenola, para-chlorofenola i 2,4-dikhlorfenoksiuksusnoi kisloty bakteral'nym soobshchestvom anaérobnogo ila.

The bacterial community of anaerobic sludge could degrade ortho-chlorophenol, para-chlorophenol, and 2,4-dichlorophenoxyacetic acid at concentrations as high as 100 mg/l. The time needed for the degradation of a given chlorinated phenol derivative increased 1.5- to 2-fold upon a twofold increase in its concentration (from 50 to 100 mg/l). The duration of the adaptation period depended on the compound studied and on its concentration. The degradation of 2,4-dichlorophenoxyacetic acid proceeded via 2,4-dichlorophenol and p-chlorophenol as intermediates; the degradation of o-chlorophenol occurred with the formation of phenol. The dynamics of p-chlorophenol degradation and chloride ion accumulation were studied.

[Properties of polysaccharide complexes produced by Azospirillum brasilense and polysaccharides isolated from these complexes]. / Svoistv polisakharidnykh kompleksov, produtsiruemykh Azospirillum brasilense, i poluchaemykh iz nikh polisakharidov.

Azospirillum brasilense strains Sp7, Sp7 (S-form), Sp107, Sp245, Sp246, S17, and 15 when cultivated in a liquid synthetic malate medium up to the end of the logarithmic phase of growth were shown to produce at least two complex polysaccharide-containing components. The components were arbitrarily called lipopolysaccharide-protein complex (LPPC) and polysaccharide-lipid complex (PSLC). The LPPCs and PSLCs from the strains Sp7, Sp107, Sp245, Sp246, and S17 were shown to interact with a wheat germ agglutinin (WGA). From PSLCs, acidic polysaccharides (PS) were isolated and their specific rotation, molecular masses, affinity for WGA, and monosaccharide composition were determined. The PSs of all strains contained rhamnose, galacturonic acid, and galactose (except the strain Sp246), and glucosamine (except the strain Sp7 (S-form)), while the PSs of the strains Sp7 and S17 also contained fucose and mannose, respectively. It is suggested that LPPCs and PSLCs may be involved in the process of interaction of azospirilla with wheat root surfaces, and that PSsare probably active parts of the LPPCs and PSLCs. The ability of LPPCs and PSs to interact with Congo red in aqueous solutions was investigated.