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N A Pomoshchnikova

Publications and source records attributed to N A Pomoshchnikova.

11 recordsLinked to original sources
PubMedDate not supplied

[Yeast peroxisomes, their development and operation].

Yeast peroxisomes (microbodies) were studied, particularly with yeast methylotrophs, using light-optical microscopy, viz. intravitam phase- and anoptral-contrast microscopy, with cytochemical as well as fixed and stained objects. The data obtained were compared with cytochemical as well as fixed and stained objects. The data obtained were compared with other evidence that we had gained on methylotrophs studied by electron microscopy and with the results obtained by investigating the peroxisomes of yeast cultures grown on nutrient containing other carbon sources. The activity of exocatalase and endocatalase, the enzymes characteristic of peroxisomes, was assayed at different growth phases of yeast methylotrophs and was found to be correlated with the cycle of development of peroxisomes. The content of biotin and inositol and its dynamics were studied in the methylotroph cells. Possible origin of peroxisomes is discussed as well as their development and the mechanism of degradation. A close contact and functional relationship have been established between peroxisomes and mitochondria.

Biotin↗
PubMedDate not supplied

[Formation and degradation of peroxisomes in yeasts].

The formation, development and degradation of peroxisomes were studied directly in growing yeast-methylotrophs under the microscope using anoptral and phase contrast. The degradation of peroxisomes was caused by their degeneration and dislocation to the central vacuole of the yeast cell. A fluorescent-microscopic technique was elaborated for detecting selectively the crystals of catalase in the cells. As was shown by intravitam studies, electron microscopy and cytochemistry, peroxisomes are directly connected with the central vacuole of the cell, enzymes being transferred from the former into the latter. Experiments conducted with different cultures have demonstrated that the high activity of exocatalase is typical of methylotrophic yeast organisms. The highest activity that was exhibited for a long period of time was found in Torulopsis molischiana.

Ascomycota↗
PubMedDate not supplied

[Determination of primary amines and protein by using fluorescamine in microorganism suspensions].

The paper describes a fluorimetric technique for determining the overall amount of primary amines and protein using fluorescamine directly in suspensions of yeast and bacterial microorganisms. The optimal conditions are selected for the reaction. The technique is highly sensitive and has an advantage over biochemical methods when one has to make many assays of amine containing compounds in biological material. The technique can find wide application in industrial practice.

Amines↗
PubMedDate not supplied

[Use of the fluorescence method to detect and quantitatively determine lipids in the cells of microorganisms].

Techniques have been developed for the detection and quantitative determination of lipids in the living cells of microorganisms (after their fixation by heating) using benzimidazole luminophores synthesized by Monocrystalreactive (USSR). When the yeast cells are stained by a luminophore, the latter is selectively bound to cellular lipids producing a brightly fluorescent complex. The intensity of fluorescence increases proportionally to an increase in the concentration of lipids in the microbial mass. The intensity of fluorescence of a microbial suspension is recorded using a spectrofluorimeter at the excitation and fluorescence maxima of 405 and 475 nm respectively. In order to assay the content of lipids in microorganisms which do not produce a homogeneous suspension, the luminophore bound to lipids is extracted from the cells with hot octane. The absolute content of lipids in the biomass is determined using a standard curve which shows the intensity of fluorescence of microorganisms and their octane extracts as a function of the lipid content in the cell.

Ascomycota↗