[Mycelial waste of tetracycline production as a component of the nutrient medium]. / Mitselial'nye otkhody proizvodstva tetratsiklina kak komponent pitatel'noi sredy.

A new composition of the nutrient medium for cultivation of the tetracycline-producing organism was developed with the fermentative hydrolysate of the tetracycline production mycelial waste as a source of nitrogen: 0.02 to 0.04 g/l by amino nitrogen. The use of the medium made it possible to increase the tetracycline yield by 5 to 25 per cent, to exclude cornsteep liquor from the medium composition, to provide a more efficient recovery of the waste and to significantly decrease the environment pollution.

[Dormant forms of Yersinia pseudotuberculosis during interaction with green algae and their exometabolites (population dynamics and ultrastructure)]. / Pokoiashchiesia formy Yersinia pseudotuberculosis pri vzaimodeistvii s zelenymi vodorosliami i ikh ékzometabolitami (populiatsionnaia dinamika i ul'trastruktura).

The dynamics of the transition of Y.pseudotuberculosis to the latent (noncultivable) state in sterile soil extraction and in soil extraction, containing Scenedesmus algae or their exometabolites, was evaluated by the bacteriological method and with the use of polymerase chain reaction. The formation of Y.pseudotuberculosis latent forms achieved its highest rate under the action of algal exometabolites (on day 11), while in the presence of algal cells such formation was delayed to 3-5 months. The partial reversion of Y.pseudotuberculosis nonculativable forms to vegetative, bacteriologically detectable forms occurred under the action of fetal serum, as well as live or killed infusoria. Transmission electron microscopy demonstrated that noncultivable Y.pseudotuberculosis had a round form, diminished cell size, denser cytoplasm and enlarged cytoplasmic space. The reversible transition of bacteria to the latent state is regarded as their adaptation to unfavorable factors during their existence in soils and water reservoirs.

Nitric oxide and cGMP modulate retinal glutamate receptors.

1. In the retina, as in other regions of the vertebrate central nervous system, glutamate receptors mediate excitatory chemical synaptic transmission and are a critical site for the regulation of cellular communication. In this study, retinal horizontal cells from the hybrid less were dissociated in cell culture, voltage clamped by the whole cell recording technique, and the currents evoked by application of excitatory amino acids recorded. 2. Responses to glutamate and its agonist kainate were reduced by approximately 50% in the presence of the nitric oxide (NO) donors sodium nitroprusside and S-nitroso-N-acetylpenicillamine. The effect of these compounds was blocked by the NO scavenger hemoglobin. 3. This effect of NO donors on kainate currents could be mimicked by the application of a membrane permeable guanosine 3',5'-cyclic monophosphate (cGMP) analogue, 8-Br-cGMP. The NO effect was also blocked by application of the guanylate cyclase inhibitor LY-83583, and by a protein kinase G inhibitor peptide. 4. In H1-type horizontal cells, stimulation of endogenous nitric oxide synthase with L-arginine reduced kainate responses, whereas application of D-arginine had no effect. 5. This receptor modulation mechanism may act in concert with other pre- and postsynaptic mechanisms to modify horizontal cell synaptic function according to the adaptational state of the retina and also may protect horizontal cells from glutamate excitotoxicity.

[Enzymatic hydrolysis of mycelial waste from the production of tetracycline]. / Fermentativnyi gidroliz mitselial'nykh otkhodov proizvodstva tetratsiklina.

The process of enzymatic hydrolysis of the mycelial waste from the manufacture of tetracycline with using Streptomyces aureofaciens was studied. For the enzymatic hydrolysis, neutral and alkaline proteinases were used. It was shown that alkaline proteinase (protosubtilin G10X) provided the most efficient hydrolysis. Optimal conditions for the hydrolysis were determined: a temperature of 42 degrees C, hydrolysis time of 4 to 6 hours and enzyme concentrations of 1.25 to 2.20 mg/ml at a mycecial waste concentration of 12.5 mg/ml. The time course of changes in amino acid and amine nitrogen levels during enzymatic hydrolysis was investigated. It was demonstrated that the hydrolysis efficiency depended on the mode of enzyme addition. The highest efficiency was observed with fractional feeding of the enzyme.

[Use of mycelial waste from the drug industry]. / Ispol'zovanie mitselial'nykh otkhodov proizvodstva meditsinskikh preparatov.

It was shown that mycelial waste (MW) from manufacture of riboxin and neomycin was useful as an active filler for press compositions and a raw material for fuels. Addition of MW to a polymer press composition, depending on the amount added, provided a 2-10-fold decrease in the time of gel formation in the mixture and hardening of the products as well as a significant decrease in their shrinkage during the hardening. Optimal physicomechanical properties were achieved when the contents of MW and polymer in the press composition were equal. Pyrolysis of dry MW at a temperature of 450-500 degrees C resulted in formation of a product which was not inferior to the known fuels in its physicochemical properties. The low freezing point of the prepared fuel as compared to that of oil fuels allowed one to recommend it as a low-temperature additive to the fuels lowering their freezing points.

[An immunochemical analysis of the induction of cytochrome P-450 isoforms in the liver of fresh-water fishes by 3-methylcholanthrene, beta-naphthoflavone and aroclor 1254]. / Immunokhimicheskii analiz induktsii izoform tsitokhrom P-450 v pecheni presnovodnykh ryb 3-metilkholantrenom, beta-naftoflavonom i arokhlorom 1254.

The cytochrome P-450 isoforms have been studied in liver microsomes of some fish species from Lake Baikal. Using the inhibitory analysis of microsomal monooxygenase activities carried out by the specific polyclonal antibodies it has been shown that 3-methylcholanthrene, beta-naphthoflavone and arochlor 1254 induce isoforms immunologically related to cytochrome P-488c but not to the rat cytochrome P-450b in fish liver microsomes. The immunologic identity in isoforms of fish and rat cytochromes induced by methylcholanthrene has not been revealed. A possibility to use the method of the inhibitory analysis of fish microsomal activities by specific antibodies to the rat cytochrome P-450 isoforms for biomonitoring and biotesting of polycyclic hydrocarbons and polychlorinated biphenyls in aquatic systems is discussed.

[Induction of the monooxygenase activity in fish tissues by polycyclic aromatic hydrocarbons and its use in the biomonitoring of water pollution]. / Induktsiia s pomoshch'iu politsiklicheskikh aromaticheskikh uglevodorodov aktivnosti monooksigenaz v tkaniakh ryb i ee ispol'zovanie dlia biomonitoringa zagriaznennykh vod.

Monooxygenase activity changes in the liver and in other tissues of certain fish species were studied after injection of methylcholanthrene and aminoanthracene to fish. Determinations of the benz(a)pyrene hydroxylase activity and activity of 7-ethoxycoumarine 0-dealkylation in the monooxygenase system were proposed as test-systems for the control of polycyclic hydrocarbon contents in natural and waste waters. The metabolic activation (Aim's test) performed by the liver microsomal fractions of different fish species was used for the analysis of sulfate cellulose industry waste waters.

[Trypsin immobilization in silica gel]. / Immobilizatsiia tripsina v gele kremnievoi kisloty.

Trypsin immobilization in an inorganic polymer, i.e. silica gel, was investigated. Properties of the immobilized enzyme were examined. It was found that the enzyme retained its activity, depending on the gel genesis and dehydration of the carrier. The effect of stabilizing supplements on the enzyme activity was studied. The enzyme immobilization was accompanied by an increase in its thermostability.

[Detection of bdellovibrios and bacteriophages in the seawater near the shores]. / Obnaruzhenie bdellovibrionov i bakteriofagov v pribrezhnoi zone moria

The frequency of occurrence of bdellovibrios and intestinal bacteriophages at the sites of contamination in the sea and along the sea shore and at the points remote from the sources of contamination was studied. At the contaminated sites bdellovibrios were revealed in 73.3-100% and bacteriophage in 75-83.4% of the samples. There was found to be a moderate correlative association between the bdellovibrios, bacteriophages and the coli titre. In the water of the shore region of the sea bdellovibrios were found in 15.4%, and bacteriophages in 20.9% of the samples. An attempt at a sanitary assessment of beaches by the data of bdellovibrio detection was unsuccessful. There was found no correlative association between the coli-titre and the bdellovibrios in the water of the shore area. Bdellovibrio proved to play an insignificant role in the processes of self-purification from the intestinal microbial flora of weakly and moderately contaminated sea water. Taking into consideration the high resistance in the sea water of the intestinal bacteriophages preference was given to them over the bdellovibrios as the index of the sea water contamination.