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PubMed1978

Taxonomy of Leucochloridium sp. (Digenea) infecting Succinea pfeifferi Rossmässler, 1835.

The anatomical and morphological variability of sporocysts and metacercariae of Leucochloridium sp. recovered from natural infected Succinea pfeifferi Rossmässler collected in the Agdenes area. Norway (63 degrees 35'N, 9 degrees 45'E), was studied by light microscopy. The results are compared with five species from the Nearctic and Palearctic with known adult stage (L. variae McIntosh, 1932; L. fuscostriatum Robinson, 1947; L. perturbatum Pojmanska, 1969; L. subtilis Pojmanska, 1969; L. fuscum Rietschel, 1970) and nine species with unknown adult stage. In the larval stages no morphological taxonomical characters were found to separate Leucochloridium sp. as a species distinct from the five (and nine) species. The variability and validity of the characters used is discussed.

Animals↗
PubMed1978

Taxonomy of coagulase-negative staphylococci: a comparison of two widely used classification schemes.

In a comparative study 351 strains of Micrococcus subgroups 1-3 (Baird-Parker, 1963, 1965, 1974) were classified according to the Kloos and Schleifer scheme (1975b). The results showed that Micrococcus subgroups 1, 2 and 3 are heterogeneous groups in the Kloos and Schleifer scheme. Strains belonging to Micrococcus subgroups 1 and 2 were mostly classified by the Kloos and Schleifer criteria as Staphylococcus hominis, Micrococcus subgroup 3 strains from the skin as S. cohnii, while Micrococcus subgroup 3 strains from urinary infections were classified mainly as S. saprophyticus. The correlation of novobiocin resistant S. saprophyticus biotype III (Baird-Parker, 1974) with S. saprophyticus (Kloos and Schleifer, 1975a, 1975b) when isolated from urine, was 80%. Although the Kloos and Schleifer scheme provides more information about biochemical characters, doubts are expressed about the validity of some of the species so delineated.

Bacteriological Techniques↗
PubMed1979

Carbohydrate composition and taxonomy of Geotrichum, Trichosporon and allied genera.

The yeast-like genera Geotrichum and Trichosporon are heterogeneous and are related with anamorphs of both ascomycetous and basidiomycetous fungi. A rearrangement can be obtained using carbohydrate composition of intact cells, studied with the aid of gas-liquid chromatography. The genus Geotrichum is restricted to ascomycetous species with a dominance of galactomannans, whereas Trichosporon is reserved for basidiomycete-like, xylose-containing species. Consequently, some new combinations are introduced in both genera. Representatives of related genera are included for comparison: e.g. Dipodascus, Hyphophichia, Cryptococcus and Filobasidium.

Carbohydrates↗
PubMed1978

Physiological and biochemical contributions to the taxonomy of the genus Chlorella. XI. DNA hybridization.

1. DNA homology was studied in 12 Chlorella species. The DNA of 88 strains was hybridized with 3H-labelled DNA from C. fusca var. vacuolata 211-8 b and from C. vulgaris 211-8m. The results indicate that the genus Chlorella is a heterogenous taxon which consists of several groups of species. 2. The "C. fusca group" comprises C. fusca var. vacuolata, C. fusca var. rubescens, and C. zofingiensis. Within this group, C. zofingiensis appears to be more closely related to C. fusca var. vacuolata than is C. fusca var. rubescens. C. fusca var. fusca does not belong to this group of taxa. 3. The "C. vulgaris group" consists of C. vulgaris, C. sorokiniana, and C. saccharophila. There are several strains which seem to assume a position intermediate between C. vulgaris and C. saccharophila. C. protothecoides is not related to this group of species. 4. Several groups of strains of C. sorokiniana with different base compositions (guanine + cytosine content) of their DNA appear to belong to the same taxon. 5. In addition to C. fusca var. fusca and C. protothecoides, also C. luteoviridis, C. minutissima, C. kessleri, and C. homosphaera seem to have so little relationship with the other species that their assignment to the genus Chlorella appears questionable.

Chlorella↗
PubMed1979

Deoxyribonucleic acid base composition and taxonomy in the genus Geotrichum Link.

The molar percentage of guanine + cytosine (% GC) in the DNA from 25 yeast-like fungi related to the genus Geotrichum has been measured. This criterion together with the biochemical characteristics allow the division of the species into 3 groups: one group resembling G. candidum (% GC: 31.5--42) and containing 8 imperfect and 6 perfect forms. In this group only G. capitatum has a lower % GC (31.5). A second group of 6 species resembling the genus Trichosporon (57--60%) and a third intermediate category of 4 species (42--53.5%) were observed. The GC-values correlate well with biochemical characters, e.g. the presence of urease, the number of organic substrates assimilated, and also with the presence of characters typical of the Ascomycetes or the Basidiomycetes.

Cytosine↗
PubMed1978

Isolation, characterization, and numerical taxonomy of Simonsiella strains from the oral cavities of cats, dogs, sheep, and humans.

Forty-nine strains of the gliding prokaryote Simonsiella were isolated from the oral cavities of cats (8), dogs (19), sheep (4), and humans (18) in Southern California by a direct isolation procedure using a complex serum-enriched medium. The numerical taxonomic analysis (unweighted pair-group method using arithmetric averages) of 57 differential traits for each strain was based on standard bacteriological diagnostic tests and included the molar guanine-plus-cytosine contents of the DNA and the relative percentages of fatty acid contents reported earlier. The resulting phenogram clustered the strains of Simonsiella into groups that correlated with sources of origin. The study included the neotype strain of Simonsiella crassa (ATCC 27504, ICPB 3651, NCTC 10283) of Australian sheep origin. The strains isolated from dogs, sheep, and humans form clusters of organisms that appear to have become adapted to live in and possibly to have evolved with their respective "hosts". In our judgment, these source-of-origin clusters represent different "ecospecies".

Animals↗
PubMed1979

Amino acid utilization patterns in clostridial taxonomy.

The polyamide layer technique for the chromatographic separation of dimethylaminonaphthalene sulphonyl amino acids has been adapted to the qualitative analysis of amino acids in media before and after the growth of micro-organisms. The method has been used to study the amino acids metabolized by cultures of proteolytic clostridia growing in a medium consisting of an acid hydrolysate of casein as a source of amino acids and small amounts of yeast extract and trypticase as sources of growth factors. The chromatograms of the media after growth showed which amino acids were used and which new amino acids were produced. Clostridium botulinum type F (proteolytic), C. ghoni, C. mangenoti and C. putrificum were found to reduce proline to 5-aminovaleric acid and to produce 2-aminobutyric acid, properties they shared with C. sporogenes and C. sticklandii. C. botulinum type G and C. subterminale used glycine, lysine, serine, and arginine but in contrast to C. sticklandii they neither reduced proline to 5-aminovaleric acid nor produced 2-aminobutyric acid. Both organisms oxidized phenylalanine, tyrosine and tryptophan to phenylacetic acid, p-hydroxyphenyl acetic acid and indole acetic acid respectively. C. lituseburense and C. scatologenes used serine, threonine and arginine and produced 2-amino butyric acid and ornithine. C. lentoputrescens, C. limosum and C. malenomenatum resembled C. tetanomorphum by using glutamic acid and tyrosine. The chromatograms always showed the physiological group to which an organism belonged and in some cases were characteristic of the species.

Amino Acids↗
PubMed1978

Taxonomy of Exophiala jeanselmei (Langeron) McGinnis and Padhye.

The black yeast-like fungus Exophiala jeanselmei (Langeron) McGinnis et Padhye was originally described as Torula jeanselmei by Langeron. Since its original description in 1928, this dematiaceous hyphomycete has been placed in the genera Phialophora, Pullularia and Rhinocladiella by various authors. Study of the type culture of E. jeanselmei has confirmed that the principle conidiogenous cells of this fungus are annellides, thus supporting its current generic disposition. After reviewing the neotype culture of Phialophora gougerotii (Matruchot) Borelli sensu Borelli, the type culture of Torula bergeri Langeron, authentic cultures of Margarinomyces heteromorpha (Nannfeldt) Mangenot sensu Mangenot, the type culture of Trichosporium heteromorphum Nannfeldt and the neotype culture of Exophiala mansonii (Castellani) de Hoog sensu de Hoog, as well as additional cultures, it was concluded that P. gougerotti sensu Borelli, T. bergeri and M. heteromorphis sensu Mangenot pro parte are conspecific with E. jeanselmei. Trichosporium heteromorphum and E. jeanselmei are not conspecific as suggested by some workers. Tr. heteromorphum is a distinct species and should be referred to as Phialophora heteromorpha (Nannfeldt) Wang. Sporotrichum gougerotti Matruchot is considered to be a later synonym of Sporothrix schenckii Hektoen et Perkins and E. mansonii sensu de Hoog as a later synonym of Microsporum mansonii Castellani. M. mansonii is held to be a later synonym of Malassezia furfur (Robin) Baillon. The neotype culture of E. mansonii produces phialides without collarettes.

Cryptococcus↗
PubMed1977

Carbohydrate composition and taxonomy of the genus Dipodascus.

Carbohydrates released during acid hydrolysis of intact cells of Dipodascus were studied by gas-liquid chromatographic analysis as their trimethylsilyl derivatives. In addition, cells were characterized by pyrolysis gas-liquid chromatography and pyrolysis mass spectrometry. The data obtained support the classification of Dipodascus uninucleatus in a separate genus Dipodascopsis. Glucuronic acid is present in D. uninucleatus and, therefore, a possible affinity to fungi classified in the Zygomycetes is considered. Dipodascus aggregatus and Dipodascus australiensis were found to be rather different, but very close to Geotrichum candidum and related species.

Ascomycota↗