[Metabolic transformation of labelled exogenous fatty acids by fungal cultures of the family Entomophthoraceae]. / Metabolicheskie prevrashcheniia ékzogennykh mechenykh zhirnykh kislot kul'turami gribov semeistva Entomophthoraceae.

Entomophthora coronata 1932 and E. conica 1716 are quite different in their fatty acid composition and the unsaturation degree of synthesized lipids. The cultures were used as models to study metabolic transformations of exogenous 14C-labeled acetic, palmitic, stearic and oleic acids as well as to compare the activities of the synthetase and desaturase enzyme complexes. The cultures were capable of transforming exogenous acetic and fatty acids into polyunsaturated arachidonic acid. E. coronata 1932 whose lipids mainly contain fatty acids with a short chain could metabolize unsaturated oleic acid to yield polyene fatty acids. However, this culture metabolized exogenous acids at a far lower rate as compared with E. conica 1716. The high content of saturated fatty acids with a short chain in the lipids might be due to the specific action of the synthetase complex and to the low activity of the desaturation enzymes. It has been demonstrated for the first time that exogenous oleic acid is converted at a high rate by the cells into arachidonic acid, a precursor of prostaglandin compounds.

[Fatty acid composition of certain species of fungi of the family Choanephoraceae]. / O zhirnokislotnom sostave fosfolipidov nekotorykh vidov gribov semeistva Choanephoraceae.

Saturated and unsaturated fatty acids with an unbranched chain and an even number of carbon atoms from C12 to C24 were found in phospholipids of the fungi Cunninghamella elegans, Cun. homothallica and Blakeslea trispora. Palmitic, oleic and linoleic acids constituted a considerable part in the fraction of fatty acids. Oleic acid (47 mole %) predominated in Cun. elegans and Cun. homothallica whereas linoleic acid (62 mole %) prevailed in Bl. trispora.

[Changes in the fatty acid composition of phospholipids during the growth process of microscopic fungi of the family Entomophthoraceae]. / Izmenenie zhirnokislotnogo sostava fosfolipidov v protsesse razvitiia mikroskopicheskikh gribov semeistva Entomophthoraceae.

The fatty acid composition of phospholipids and its changes during growth of two cultures of microscopic fungi belonging to the family Entomophthoraceae have specific peculiarities. Fatty acids in the composition of phospholipids contain from 10 to 20 carbon atoms in the chain; unsaturated fatty acids prevail among them, and constitute about 60% in the phospholipids of Ent. coronata 1932 and about 70% in the phospholipids of Ent. conica 1716. The content of arachidonic acid in the phospholipids of the both cultures is high (up to 17%). The fatty lipids of phospholipids are actively involved in metabolism in the process of the fungal growth, particularly in Ent. coronata 1932 which is characterized by a higher level of metabolism. The total degree of unsaturation of phospholipids changes only slightly during the growth of the two cultures.

[Lipid composition of certain predatory species of fungi of the genus Arthrobotrys]. / Sostav lipidov nekotorykh vidov khishchnykh gribov roda Arthrobotrys.

The aim of this work was to study the effect of the composition of the medium on the biosynthetic activity of fungi belonging to the genus Arthrobotrys, the content of different lipid fractions in them, and their fatty acid composition. The following fractions typical of the majority of microbial species were found in the lipid composition of these predaceous fungi: phospholipids, monoglycerides, diglycerides, sterols, free fatty acids, and triglycerides. The fungi were capable of accumulating from 2.4 to 13.2% of lipids in the mycelium. The elevated synthesis of lipids was observed in Arthrobotrys longa 14 and A. musiformis 123 in the modified Meise medium and in wort. The content of lipids in the mycelium was low and the fractions of phospholipids and sterols prevailed upon the growth in chemically defined media. The content of triglycerides was high when the fungi grew in the Meise medium and wort. The fatty acid composition of lipids was identical in all of the studied cultures. The principal saturated fatty acids were myristic, palmitic and stearic. Among unsaturated fatty acids, a high content of oleic and linoleic acids was registered.

[Age changes in the lipid fatty acid makeup of cultures of the family Entomophthoraceae]. / Bozrastnye izmeneniia zhirnokislotnogo sostava lipidov u nekotorykh kul'tur semeistva Entomophthoraceae.

The rate of biosynthesis of lipids and their fatty acid composition were studied in four cultures of microscopic fungi belonging to the family Entomophthoraceae in the course of their growth. The cultures synthesized from 23% to 43% of lipids. The lipids comprised fatty acids containing from 9 to 24 carbon atoms in the chain. The lipids differed in their fatty acid composition and the degree of saturation: unsaturated fatty acids (50-60%) prevailed in the lipids of Ent. conica 1716, Ent. thaxteriana 1711 and 1931, while saturated fatty acids (70%) predominated in the lipids of Ent. coronata 1710. Isomers with different position of double bonds were found among C18-unsaturated fatty acids (two octadecenic, three octadecadienic and two octadecatrienic acids). Branched fatty acids were detected in low amounts in the lipids. The character of changes in the fatty acid composition of lipids was different in the process of the cultural growth.

[Electron microscopic study of normal Bacillus anthracoides spores and after exposure to a chloroactive disinfectant]. / Elektronno-mikroskopicheskoe izuchenie spor Bacillus anthracoides v norme i pri vozdeistvii khloraktivnogo dezinfektanta.

The fine structure of Bacillus anthracoides spores is similar in general to that of other, taxonomically related species of spore forming bacteria. However, the former is characterized by a well-developed multilayered exosporium and the heterogeneous structure of an envelope. The lethal effect of a chloroactive disinfectant (2/3 of calcium hypochlorite basic salt) is caused by changes in the structural organization of spores, which interferes with the normal permeability barrier and metabolic processes.

[Variant of Bacillus anthracoides]. / O variante Bacillus anthracoides.

A comparative study of the Bacillus anthracoides culture and its variant has shown that the latter differs drastically from the parent culture in the shape and consistence of colonies, the size of spores and vegetative cells, the rate of spore germination in MPB, and the resistence to steam treatment and chloroactive disinfectants.

[Use of a mass spectrometric method for studying the oxygen demand of suspensions of resting Bacillus anthracoides spores]. / Primenenie mass-spektrometricheskogo metoda dlia izucheniia potrebleniia kisloroda suspenziiami pokoiashchikhsia spo Bacillus anthracoides.

Oxygen assimilation by the spore suspensions of Bacillus anthracoides under sterile conditions was continuously registered by means of a modified mass-spectrometry technique using an original reaction vessel. The sensitivity of the technique is 2.10(-2) mcl O2 per 1 mg of dry biomass per hour. The technique made it possible to determine the level of endogenous respiration activity in the spore suspensions of Bacillus anthracoides.

Influence of phosphorus on the composition of polar lipids of Actinomyces olivaceus.

The influence of phosphorus on the composition of the lipids of Act. olivaceus was studied. It was found that the phosphorus content in the culture medium can serve as a regulator of the synthesis of definite lipids. In the presence of a phosphorus deficiency in the medium (0.0006 g/100 ml), not only the ratio of the polar and neutral fractions, but also the composition of the polar lipids changes, namely: The content of cardiolipin and phosphatidylinositol mannoside is decreased; the content of phosphatidylethanolamine drops from 25.6% to 1.25%. An ornithine-containing lipid is detected among the polar lipids (4--4.5%). Changes in the composition of the membrane lipids are not accompanied by any visible sharp changes in the structural organization of the membrane apparatus.

[Oxygen consumption by suspensions of Bacillus anthracoides spores]. / O potreblenii kisloroda suspenziiami spor Bacillus anthracoides

The respiration rate of spore suspensions of Bacillus anthracoides 96 was assayed by mass spectrometry employing a hermetically sealed reaction vessel constructed for this purpose. The rate of respiration was found to depend on the method of preparing suspensions, the duration of their storage at +4 degrees C, the physiological state of spores, and the action of a disinfectant containing chlorine on them.

[Effect of vitamin A on the biosynthesis of carotene by Blakeslea trispora]. / Vliianie vitamina A na biosintez karotina Blakeslea trispora

Retinol stimulates carotene synthesis in the microscopic fungus Blakeslea trispora; the stimulating effect of vitamin A is not manifested in the presence of cycloheximide. Vitamin A and beta-ionone are presumed to affect carotene synthesis in Blakeslea trispora by imitating the action of natural compounds stimulating isoprenoid synthesis--trisporic acids.

[Effect of calcium hypochlorite on Bacillus anthracoides spores]. / Deistvie gipokhlorita kal'tsiia na spory Bacillus anthracoides

The sublethal dose of calcium hypochlorite (CH) of 0.2--0.3 mg/ml active chlorine did not cause, after 5 min, morphological changes in the spores of Bacillus anthracoides which could be detected by phase contrast microscopy, or a decrease in the content of dipicolinic acid (DPA) in the spores. Further cultivation of the spores treated with the sublethal dose of CH om MPA resulted in a delay of changes which were typical of normal germination process (swelling, loss of light refraction, decrease in DPA content). The action of the lethal dose of CH (0.2--0.3 mg/ml active chlorine during 1.5 hr or 5.6 mg/ml active chlorine during 1 hr) causes a decrease in light refraction, changes in the dimensions of spores, and a decrease in the content of DPA in the spores by a factor of 4--5. A sharp decrease in the content of DPA in the spores may characterize not only their germination but also their death caused by lethal doses of the chlorine containing disinfectant.

[Comparative effect of various chloroactive compounds on the enzyme systems of Bacillus anthracoides spores]. / Sravnitel'noe deistvie razlichnykh khloraktivnykh soedinenii na fermentnye sistemy spor Bacillus anthracoides

The effect of various chloroactive compounds containing equal amounts of chlorine on respiration enzymes was studied in the spores of Bacillus anthracoides 96. These compounds inhibited the activity of malate dehydrogenase, fumarase, and aconitase but stimulated the activity of glucose-6-phosphate dehydrogenase, succinate dehydrogenase, and ketoglutarate dehydrogenase. Therefore, the action of these compounds is rather specific, and the inhibition of the activity of some enzymes is one of the factors causing the sporocidal effect.

[Change in the activity of the enzymatic systems of Bacillus anthracoides spores during germination and under the action of Ca hypochlorite]. / Izmenenie aktivnosti fermentnykh sistem spor Bacillus anthracoides pri prorastanii i pri deistvii gipokhlorita Ca

The activity of the enzymes of the citric acid cycle, glycolysis, and hexose monophosphate pathway was studied during germination of the spores of Bacillus anthracoides and upon their treatment with calcium hypochlorite. No activity of isocitrate dehydrogenase and glucose-6-phosphate dehydrogenase was found in the extracts of the vegetative cells, contrary to the spores and initiated spores. The activity of other enzymes changes but slightly in the course of germination of the spores. Treatment of the spores with calcium hypochlorite inhibited their initiation and germination and the activity of several enzymes, especially malate dehydrogenase, isocitrate dehydrogenase, and fumarase.