Cellular Long-chain Fatty Acid Compositions Research Articles

The value of certain chemotaxonomic methods in the identification of food related yeasts

A total of 166 food-related yeast species were selected and used as a basis for a taxonomic study. An extensive survey has been conducted on the cellular long-chain fatty acid composition (LCFA), G+C values, coenzyme Q analyses and orthogonal field alternation gel electrophoresis (OFAGE) of yeasts associated with food in order to obtain rapid and reliable identification of the yeasts. In the above survey, the yeast strains were cultured under standardized conditions, after which the different profiles of each species were examined using the above-mentioned techniques. The chemotaxonomic data were compared with data obtained by means of standard conventional methods using a comparative model. None of the chemotaxonomic techniques proved to be solely adequate in characterizing isolated species. Our data suggest, however, that the coordinate use of all the above techniques provide a reliable approach for differentiating between food yeast species.

The Potential Use of Cellular Long-chain Fatty Acid Composition in the Taxonomy of the Carotenoid Pigment Producing Genera Rhodosporidium Banno and Rhodotorula Harrison

The cellular long-chain fatty acid composition and phenotypic characteristics of 50 strains of carotenoid pigment producing yeasts representing 9 species of Rhodotorula, 7 species of Rhodosporidium and a single species of Cystofilobasidium were determined and used as a basis for a numerical taxonomic study. Two major groups subdivided into 14 sectors were identified which are differentiated by the ratio between oleic acid (C18:1) and linoleic acid (C18:2) and different phenotypic characteristics.

The Yeast Family Lipomycetaceae Novák et Zsolt emend. Van der Walt et al. and the Genus Myxozyma Van der Walt et al. 1. A Historical Account of its Delimitation and 2. The Taxonomic Relevance of Cellular Long-Chain Fatty Acid Composition and Other Phenotypic Characters

Summary An evaluation of the classification of the family Lipomycetaceae is given and includes a chronological account of how the various systematicists viewed, demarcated and classified this yeast family. In addition, the cellular long-chain fatty acid compositions of species representing this family were determined and compared with its present status. A total of thirty five strains representing the yeast genera Dipodascopsis, Lipomyces, Myxozynta, Waltomyces and Zygozyma , were arranged in accordance with their cellular long-chain fatty acid compositions, coenzyme Q systems and carbon source utilization patterns. Results obtained divided the family Lipomycetaceae, together with the genus Myxozyma , into two groups, according to the presence or absence of linolenic acid (C18 :3). The species in this family are also suggestive of two lines based on habitat specificity and ascospore morphology. Both lines however, showed a trend towards a reduction or increase in phenotypic characters i.e. linolenic acid, carbon sources utilized, number of isoprenoid units in coenzyme Q and the ability to form hyphae, pseudomycelium or only budding cells.

The Significance of Long-Chain Fatty Acid Compositions and Other Phenotypic Characteristics in the Genus Pichia Hansen emend. Kurtzman

Summary The cellular long-chain fatty acid compositions of eighty three species representing the genus Pichia Hansen emend . Kurtzman were analysed by gas-liquid chromatography. These results were compared with other criteria (viz. carbon source utilization patterns, coenzyme Q systems and G+C contents) in order to determine relationships between these species. It was found that yeasts characterized by similar cellular long-chain fatty acid compositions, do not necessarily have similar coenzyme Q systems, carbon source utilization patterns and G + C values. In the case of varieties of a species and species considered to be conspecific, similar phenotypic results were obtained. In some instances, differences in cellular long-chain fatty acid compositions were in agreement with DNA/DNA reassociation studies viz. Pichia opuntiae and Pichia thermotolerans . The results obtained were also compared with the phylogenetic scheme proposed by Wickerham (1970). The yeast species which occurred on any one phylogenetic line did not contain identical long-chain fatty acid compositions. A progressive change in long-chain fatty acid compositions in some lines were evident. The species considered to be primitive did not produce linolenic acid (C18 : 3).

A Taxonomic Study of the Yeast Genus Candida Berkhout

The cellular long-chain fatty acid composition and electrophoretic karyotypes of 117 strains of Candida were determined and used as a basis for a taxonomic study of this genus. Three major groups subdivided into 15 entities were proposed which are differentiated by the absence or presence of linoleic (C18 : 2) and linolenic acid (C18 : 3) and different electrophoretic karyotypes. Interesting correlations between fatty acid composition, electrophoretic karyotypes, coenzyme Q systems, G+C contents, serological data and proton magnetic resonance spectra were observed. The coordinate use of these different phenotypic characters, provides a convenient method to establish close relationships between the different strains and species. Cellular long-chain fatty acid composition and electrophoretic karyotypes both proved to be valuable criteria in the differentiation of species of the genus Candida .

The Significance of Cellular Long-Chain Fatty Acid Compositions and Other Criteria in the Study of the Relationship Between Sporogenous Ascomycete Species and Asporogenous Candida Species

Summary The relationship between 34 Candida species and 51 ascosporogenous yeasts were studied on the basis of long-chain fatty acid composition, coenzyme Q systems, carbon-source utilization patterns and other phenotypic characteristics. Close relationships were found between nine teleomorph and anamorph yeasts, i. e. Candia norvegensis and Pichia norvegensis, Candida parapsilosis and Lodderomyces elongisporus, Candida krusei and Issatchenkia orientalis, Candida utilis and Pichia jadinii, Candida lusitaniae and Clavispora lusitaniae, Candida pelliculosa and Pichia anomala, Candida cifferri and Stephanoascus cifferri, Candida famata and Debaryomyces hansenii and Candida lipolytica and Yarrowia lipolytica .

The Value of Orthogonal-Field-Alternation Gel Electrophoresis and Other Criteria in the Delimitation of Anamorphic/Teleomorphic Relations

Summary The electrophoretic karyotypes of 51 strains representing the genera Candida, Kluyveromyces, Pichia and Saccharomyces were analysed by orthogonal-field-alternation gel electrophoresis (OFAGE). These results were compared with other criteria (viz. cellular long-chain fatty acid compositions, coenzyme Q type, G+C values and physiological features) in order to establish possible anamorph/teleomorph relations. Close correlations were found between perfect/imperfect states except for Saccharomyces exiguus and Candida holmii .

The relationship between freezing resistance and fatty acid composition of yeasts

The relationship between freezing resistance and cellular long-chain fatty acid composition of 18 selected yeast strains was studied. All strains produced a series of saturated and unsaturated evennumbered fatty acids ranging from 14 to 20 carbons in length. The majority of the freeze-resistant yeasts were found among fermentative species with a content of oleic acid above 40%.

The relationship between freezing resistance and fatty acid composition of yeasts

The relationship between freezing resistance and cellular long-chain fatty acid composition of 18 selected yeast strains was studied. All strains produced a series of saturated and unsaturated evennumbered fatty acids ranging from 14 to 20 carbons in length. The majority of the freeze-resistant yeasts were found among fermentative species with a content of oleic acid above 40%.

Taxonomic relationships of Cryptococcus and Tremella based on fatty acid composition and other phenotypic characters.

The cellular long-chain fatty acids present in 33 strains, representing 15 species of Cryptococcus, and 4 species of Tremella, were determined by gas chromatography. According to the relative amounts of fatty acid methyl esters, the Cryptococcus species studied were divided into four main groups. Possible relationships between species representing the two genera are presented in a new model, where cellular long-chain fatty acid compositions and other phenotypic characteristics are included.

The Significance of Long-Chain Fatty Acid Composition and Other Phenotypic Characteristics in Determining Relationships Among Some Candida, Kluyveromyces and Saccharomyces Species

Summary Thirty one species representing the genera Candida, Kluyveromyces and Saccharomyces were grouped according to their cellular long-chain fatty acid compositions, carbon source utilization patterns and degree of cell differentiation. The coordinate use of these different phenotypic characteristics provided a convenient method to establish possible teleomorph and anamorph relations as well as similarities among yeasts. Yeasts with known teleomorph-anamorph relations were generally closely grouped while unrelated yeasts were positioned some distances from each other. An interesting correlation was also found between the different phenotypic characteristics of the species studied. The presence of linolenic acid correlated with the formation of pseudomycelium and/or true hyphae as well as the utilzation of a large number of carbon sources while the absence of linolenic acid correlated with the formation of rudimentary pseudomycelium and/or single cells and the utilization of only a few carbon sources.

The use of cellular long-chain fatty acid composition in the identification of some yeasts association with the wine industry

The cellular long-chain fatty acid compositions of 104 yeast strains representing 39 species associated with the wine industry were determined by gas-liquid chromatography. It was possible to differentiate between all the species examined except Schizosaccharomyces malidevorans and Schizosaccharomyces pombe which had a similar fatty acid composition, as well as between some strains within Saccharomyces cerevisiae and other species. This method resulted in identification within three days which compares favourably with the seven to ten days and longer required for conventional methods.

The cellular long-chain fatty acid composition of species representing the Genus Pichia Hansen emend. Kurtzman

Summary Cellular long-chain fatty acid compositions of 43 strains representing 33 species of the genus Pichia Hansen emend . Kurtzman were analyzed by gas-liquid chromatography. The 43 strains were characterized mainly by palmitic (C16:0), palmitoleic (C16:1), stearic (C18:0), oleic (C18:1) and linoleic acid (C18:2). Two groups were obtained on the basis of fatty acid content. The first group comprises strains which were characterized by a higher mean percentage of palmitic acid (C16:0) compared to palmitoleic acid (C16:1) and the second group by a higher mean percentage of palmitoleic acid (C16:1) compared to palmitic acid (C16:0). With this method it was possible to develop a data base for Pichia species, which may be used for identification purposes.

Long-chain fatty acid composition as an aid in the classification of the genus Saccharomyces

Summary The cellular long-chain fatty acid composition of 5 species of Saccharomyces were determined, grouped according to their similarities and compared. Consequently, the Saccharomyces strains were clustered into 5 groups (I to V) on the basis of their fatty acid content. The fatty acid composition for each of the 5 species proved to be unique.

The Long-chain Fatty Acid Compositions of Species Representing the Genera Saccharomyces, Schwanniomyces and Lipomyces

The cellular long-chain fatty acid composition of 31 yeast strains representing species of Saccharomyces, Schwanniomyces and Lipomyces was determined by gas chromatography of fatty acid methyl esters. The fatty acid profiles of the strains representing the three genera were distinguishable from each other. The Saccharomyces and Lipomyces strains were characterized mainly by the presence of palmitic (C16:0), palmitoleic (C16:1), stearic (C18:0) and oleic (C18:1) acid as the major fatty acids. The Schwanniomyces strains were characterized by the presence of palmitic, palmitoleic, oleic, linoleic (C18:2) and linolenic (C18:3) acid. The 31 strains were divided into three groups on the basis of their fatty acid content. The first group was characterized by a higher concentration of linoleic and linolenic acid, the second group by the absence of linolenic acid, and the third group by the absence of both linoleic and linolenic acid.

A rapid method to identify some species of the Dipodascaceae and Endomycetaceae

The cellular long-chain fatty acid compositions of 15 species representing the Dipodascaceae and Endomycetaceae were extracted by saponification and analyzed as methyl esters by gas chromatography. The strains were charecterized by palmitic acid, palmitoleic acid, oleic acid and linoleic acid. The strains were divided into two major groups while group 2 was subdivided into two subgroups on the basis of fatty acid composition. Group 1 was characterized by a high percentage linoleic acid while group 2 contained a lower percentage. With this method, it was possible to identify the 15 species within 52 h as compared with 7–10 days for the more conventional methods.