[Studies on the cell wall of yeast of the genus Rhodotorula. X. Isolation and purification of cell-wall glycoproteins from Rhodotorula rubra (author's transl)]. / Etudes des parois de levures du genre Rhodotorula. X. Isolement et purification de glycoprotéines de la paroi de Rhodotorula rubra

Following ethylene diamine treatment of the cell wall of Rhodotorula rubra, a water soluble fraction has been isolated. This fraction can be resolved into three glycoproteins and one protein. The major part is a glycoprotein, purified to homogeneity which has a molecular weight of 64 000. The glyco-part of this protein contains mannose, glucose and one residue of glucosamine. After pronase treatment, the presence of an ""Asparaginyl-N-acetylglucosamine" linkage is established by the existence of one aspartic acid residue and one glucosamine residue. After permethylation, the initial data give some evidence that the branching points in the molecule were the carbon atoms 3 and (or) 6 of the mannose moiety and that some glucose moieties are bound to the non-reducing terminal end.

The distribution of pyrophosphatidic acid in nature.

The occurrence of a novel phospholipid, pyrophosphatidic acid, in the lipid extracts of yeasts (23 species), bacteria (E. coli), algae (chlorella), mammalia (human, rabbit, guinea pig, and mouse), insect (cockroach), fish (carp), mollusc (clam), and spermatophyta (spinach) was investigated. Pyrophosphatidic acid was found exclusively in the lipid extracts of several kinds of yeast species, but not in other normal living species (animals, plants, and microorganisms) so far investigated. All of the yeast species containing this lipid belong to the asporogenous yeasts (Cryptococcus neoformans CBS-132, Cryptococcus laurentii Z 6-5, Rhodotorula glutinis H 3-9-1, Rhodotorula rubra AY-2, Kloeckera apiculata KK-3, and Trichosporon cutaneum KC 4-3), and ballistosporogenous yeast (Sporobolomyces salmonicolor WF 174). In contrast, no detectable amount of pyrophosphatidic acid was found in the cellular lipids of ascosporogenous yeasts.

Cytological and chemical changes in cell walls of Rhodotorula gracilis. III. Characteristics and life cycle of the yeast.

The phenotype and genotype of six strains of the genus Rhodotorula Harrison and of one strain of the genus Cryptococcus Phaff et Fell, with anomalous thickening of cell walls were investigated. The present studies showed that the strains investigated represent different stages of the life cycles of the genus Rhodosporidium Banno. The anomalous thickening of the cell walls can be explained by extreme conditions resulting in the formation of surviving forms (teliospores, chlamydospores).

[Makeup of the extracellular lipids in Rhodotorula glutinis yeasts]. / Sostav ékstratselliuliarnykh lipidov u drozhzhei Rhodotorula glutinis.

The fractional composition of extracellular lipids extracted with hexane and ethanol was studied in the yeast Rhodotorula glutinis 35 by thin-layer chromatography. The two extracts of extracellular lipids were found to be similar in composition though differing in the quantitative content of individual fractions. The fractional composition of extracellular lipids differed from that of intracellular lipids. The peculiarity of the fractional composition of extracellular lipids can be accounted for by the specificity of its fatty acid and alcohol composition.

Carbohydrate patterns of Candida, Cryptococcus and Rhodotorula species.

Within the genus Candida three distinct groups are recognized on the basis of carbohydrate patterns of intact whole cell hydrolyzates. In the first, ascomycetous, group mannose is dominant, while rhamnose, fucose and xylose are absent; this is indicative of an affinity with endomycetous families. Among the basidiomycetous representatives, two groups can be recognized. One group is usually characterized by the presence of xylose and has a low mannose content. The pattern is typical for Cryptococcales and Tremellales (e.g., Cryptococcus, Trichosporon, Bullera and Tremella). The other basidiomycetous group is characterized by the presence of fucose and/or rhamnose with significant amounts of mannose. This pattern is characteristic for Sporobolomycetaceae.

[Fatty acid and fractional makeup of the lipids of osmotolerant yeasts]. / Zhirnokislotnyi i fraktsionnyi sostav lipidov osmotolerantnykh drozhzhei.

Osmotolerant yeast cultures differ in their fatty acid and fraction composition of total lipids from yeast cultures of the same or related species from other habitat. Their lipid fatty acids are represented by C14--C18 acids. Their fraction composition of lipids is characterized by a low content of free fatty acids and diglycerides and an elevated content of esters of sterines and wax. The fatty acid and fraction composition of lipids depend on the concentration of NaCl and the C/N ratio in the medium.

[Fatty acid makeup of the lipids in soil and epiphytic yeasts]. / Zhirnokislotnyi sostav lipidov pochvennykh i épifitnykh drozhzhei

The fatty acid composition of lipids was compared among yeast cultures belonging to the genera Rhodotorula, Lipomyces, and Cryptococcus. These lipids contain C10--C26 fatty acids, mainly with the even number of carbon atoms. Palmitic acid (C16 : 0) and oleic acid (C18 : 0) predominate. In the majority of the strains, the sum of unsaturated acids exceeds the sum of saturated acids. The content of unsaturated acids in the lipids of the epiphytic yeast Rhodotorula is higher than in the soil yeast Lipomyces. Besides C12--C18 acids, C22--C26 acids were identified by GLC at preset temperatures. Lignoceric acid (C24 : 0) was found for the first time in the cultures of Rhodotorula, Lipomyces, and Cryptococcus, and cerotinic acid (C16 : 0) was also detected in the Rhodotorula yeast. Fatty acids with a long chain are registered in the strains of Rhodotorula more often than in the strains of Lipomyces and Cryptococcus.

[Use of infrared spectroscopy for studying the chemical composition of yeast cell walls]. / Primenenie infrakrasnoi spektroskopii dlia izucheniia khimicheskogo sostava kletochnykh stenok u drozhzhei.

Infrared spectra of intact cells and cell walls of several yeast cultures were recorded by means of immersion of a freeze-dried sample in KBr. The relative intensity and position of absorption bands were analysed, and the bands were related to the respective components of cell walls. The data of IR spectra of various yeast cells were compared to draw conclusions about the chemical composition of their cell walls (the content of protein-peptide and lipid components). The chemical composition of the cell walls changed if one and the same culture was grown on different media.

[IR spectrophotometric study of a mixed culture of Streptococcus lactis, strain MSU, and Rhodotorula colostri with agitation of the medium]. / IK-spektrofotometricheskoe issledovanie sovmestnoi kul'tury Streptococcus lactis shtamm MGU i Rhodotorula colostri v usloviiakh peremeshivaniia sredy.

Physiological aspects of Streptococcus lactis, strain MSU development in mixed culture with Rhodotorula colostri were studied in connection with nisin biosynthesis. By the IR spectra the average content of the main components in the monoculture cells of S. lactis and its association with the yeast in the stationary growth phase was the following by dry weight: 54-58 per cent of protein, 14-16 per cent of nucleic acids, 26-28 per cent of carbohydrates and 3-5 per cent of lipids. Glucose and nitrogen in the fermentation broth were consumed completely. A significant quantity of KH2PO4 remained in the fermentation broth. Lactic acid excretion was observed. S. lactis, strain MSU was the leading component of the association under the studied cultivation conditions because just its IR spectra dominated in the spectra of the mixed culture.

[Fractional makeup of the lipids of some yeast species]. / Fraktsionnyi sostav lipidov nekotorykh vidov drozhzhei

The fractional composition of lipids was studied in 32 yeast strains belonging to the genera of Rhodotorula Harrison, Lipomyces Lodder et Kreger van Rij and Cryptococcus Kutz. The effect of C/N ratio in the growth medium on the content of various lipid fractions was studied. Lipids of the most studied cultures were found to contain di- and triglycerides, waxes, free fatty acids, sterines, their esters, and phospholipids. The fraction of monoglycerides was also detected in Rhodotorula and three species of Cryptococcus, but not in Lipomyces and Cr. laurentii. If C/N ratio equals 10, the predominant lipid component in Lipomyces is triglycerides, and in Rhodoturula and Cryptococcus phospholipids. The fraction of triglycerides prevailed in all cultures at C/N ratio of 100. The content of phospholipids decreased with an increase of C/N ratio in the medium from 10 to 100.

[Macrophage activation by polysaccharides from yeast-like fungi]. / Aktivatsiia makrofagov polisakharidami iz drozhzhepodobnykh gribov.

The effect of polysaccharides isolated from yeast-like fungi on diverse activities of murine peritoneal macrophages was studied in experiments in vitro. Yeast polysaccharides had a nonspecific activating effect on macrophages in tissue culture. They enhance the adhesion of macrophages to glass, stimulate phagocytosis and intracellular digestion, and change the chemotactic activity. The activity of polysaccharides directly correlates with their molecular weight. There is a relationship between the biological activity and chemical structure of polysaccharides. The beta-structural polysaccharides are capable of activating the functions of macrophages, while beta-structural dextrans do not possess such properties.