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Biomedical subjects

V D Kuznetsov

Publications and source records attributed to V D Kuznetsov.

At least 55 records · Page 3Linked to original sources
PubMed1976

[Electron microscopic study of the structure of colonies of culture of Actinomyces parvullus producing actinomycin D].

Ultrafine structure of the mycellium of the colonies of active and non-active variants of Actinomyces parvullus, producing actinomycin D was studied. Functional rebuilding of the cells of the substrate and aerial mycellium during the colony development in connection with synthesis and accumulation of the antibiotic by the culture was shown. The process of production and secretion of an amorphous material in the cells of the substrate mycellium of the active variant of Actinomyces parvullus was studied. It was supposed that the above process was associated with the antibiotic synthesis by the organism cells. The phenomenon of intrahyphal growth of the hyphae observed in both the active and inactive variants of the colonies was rather characteristic of the cells of the culture studied.

Actinomyces↗
PubMed1975

[Study of the population makeup and antibiotic and transamidinase activity of Actinomyces streptomycini 773 stored for a long period in a lyophilized, dried state].

Studies on variation of the streptomycin-producing organism Act. streptomycini 773 on its storage in lyophilized state showed that prolonged maintenance (for 8 years) resulted in increased percentage of "oligospore" (up to 6.9 per cent) and asporogenic (up to 6.0 per cent) variants in the population. The variants had lower transamidinase and antibiotic activity.

Actinomyces↗
PubMed1975

[Study of the structure of colonies of active and inactive Actinomyces parvullus variants using luminescence and scanning microscopy].

The colony structure of the active and inactive proactinomycete-like variants of Actinomyces parvullus producing actinomycin D was studied with luminescent and scanning microscopy. Clear differentiation of the colony profile was shown by the structure and functions of the mycelium layers. A zone of active synthesis and accumulation of the antibiotic was observed in the colonies of the active variant in the upper part of the substrate mycelium with reddish-yellow self luminescence in UV light and characteristic close hyphae "cemented" by the intracellular substance. Formations of the granule type were often noted on the hyphae of that layer. The layer of the aerial mycelium was loosely connected with the substrate mycelium and consisted of sporophores and spore chains partially broken into single spores. The colonies of the inactive proactinomycete-like variant had a slightly differentiated profile with a sponge-like structure, no zones of the antibiotic synthesis being found. The presence of the intracellular substance was observed in the upper part of the colony supersubstrate mycelium.

Dactinomycin↗
PubMed1975

[Effect of lyophilization methods on the formation of free radicals, the survivability and makeup of a population of the lincomycin producer].

It was shown that a short-time exposure of the spores of Act. roseolus 981 to air (oxygen) on their lyophilization by the chamber method resulted in formation of increased numbers of the free radicals in the lyophilized spores suspension and decreased the survival of the spores on their further storage under vacuum. The phenomena were less pronounced when the exposure of the spores to the air was excluded by using the collector method of lyophilization. This testified to the advantages of the latter method as compared to the chamber one. No effect of the lyophilization methods on the population composition of the spontaneous variants of Act. roseolus 981 was observed.

Cell Survival↗