RESUMEN
Descriptions are given for the two new anamorphic ascomycetous yeasts Candida germanica (type strain NRRL Y-27064, CBS 4105) and Candida neerlandica (type strain NRRL Y-27057, CBS 434). The species were isolated, respectively, from the atmosphere over Germany and from pressed yeast cake in The Netherlands. Phylogenetic analysis of 26S domain D1/D2 ribosomal DNA sequences places C. germanica near Pichia philogaea, whereas C. neerlandica is a member of the Lodderomyces elongisporus/Candida albicans clade.
Asunto(s)
Candida/clasificación , Candida/genética , Microbiología del Aire , Candida/fisiología , ADN de Hongos/análisis , ADN de Hongos/genética , ADN Ribosómico/análisis , ADN Ribosómico/genética , Datos de Secuencia Molecular , Técnicas de Tipificación Micológica , Filogenia , ARN Ribosómico/genética , Análisis de Secuencia de ADNRESUMEN
Three new anamorphic ascomycetous yeasts are described: Candida anglica (type strain NRRL Y-27079, CBS 4262), Candida cidri (type strain NRRL Y-27078, CBS 4241), and Candida pomicola (type strain NRRL Y-27083, CBS 4242). These three species were isolated from cider produced in the United Kingdom, and their identification was determined from unique nucleotide sequences in the species-specific D1/D2 domain of large subunit (26S) ribosomal DNA. Phylogenetic analysis of D1/D2 sequences placed C. anglica near Candida fragi, C. cidri near Pichia capsulata, and C. pomicola in the Pichia holstii clade.
Asunto(s)
Bebidas/microbiología , Candida/clasificación , Candida/aislamiento & purificación , Malus/microbiología , Candida/genética , Candida/fisiología , ADN de Hongos/genética , ADN Ribosómico/genética , Filogenia , Especificidad de la EspecieRESUMEN
Cryptococcus adeliensis sp. nov. (CBS 8351) is described based on phenotypic characteristics and molecular sequence analysis of the D1/D2 large subunit and internal transcribed spacer regions of the ribosomal DNA. Molecular comparisons include species closely related to Cryptococcus albidus and several species isolated from the Antarctic. C. adeliensis, which has a cold-adapted xylanase, was isolated from Terre Adelie, Antarctica. ATCC 34633, which has a mesophilic xylanase, was identified as Cryptococcus albidosimilis.
Asunto(s)
Cryptococcus/aislamiento & purificación , Xilosidasas/biosíntesis , Regiones Antárticas , Cryptococcus/clasificación , Cryptococcus/enzimología , Cryptococcus/crecimiento & desarrollo , Medios de Cultivo , ADN Ribosómico/análisis , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia , Análisis de Secuencia de ADN , Xilano Endo-1,3-beta-XilosidasaRESUMEN
With the increase in the number of immunocompromised hosts, the number of fungal pathogens has increased markedly. Identification and classification, especially of yeast species and strains, is often difficult when based solely on phenotypic characteristics. Since it became clear that different fungal pathogens require specific treatment strategies, there is a need for simple, rapid and reliable methods to identify fungal isolates. Polymerase chain reaction (PCR) fingerprinting was successfully applied here to identify yeast isolates. Microsatellite [(GTG)5; (GACA)4] and minisatellite [(5'GAGGGTGGCGGTTCT 3'), derived from the core-sequence of the phage M13] specific primers were used as single primers in the PCR to amplify hypervariable interrepeat DNA sequences from over 200 European, American and Australian clinical isolates within the genus Candida. Each species, represented by its type strain, could be identified by a specific multilocus pattern, allowing for the assignment of all the isolates to the appropriate species. Intra-species variation in the multilocus profiles was about 20% compared to inter-species variation, which was up to 80%. Anamorph-teleomorph pairs could be identified by highly homologous PCR fingerprint patterns. PCR fingerprinting was more discriminatory when compared with routinely used biochemical tests (Vitek YBC and API ID 32C). PCR fingerprinting has proven to be a powerful tool for the identification of medically important yeasts. It is rapid, sensitive, reliable, highly reproducible, stable in vitro and in vivo, and applicable to large scale experiments. Potential applications include: yeast taxonomy, epidemiology, environmental surveys, and improvement of the diagnosis of mycotic diseases.
Asunto(s)
Candida/genética , Candida/aislamiento & purificación , Dermatoglifia del ADN , ADN de Hongos/análisis , Reacción en Cadena de la Polimerasa , Australia , Candida/clasificación , Candidiasis/microbiología , Europa (Continente) , Humanos , Repeticiones de Minisatélite , Filogenia , Reproducibilidad de los Resultados , Especificidad de la Especie , Estados UnidosRESUMEN
A new member of the 2-micron family of plasmids, named pTD1, was found in the yeast Torulaspora delbrueckii, a widespread yeast associated with food. Nucleotide sequences revealed the presence of a pair of inverted repeats and three open reading frames, one of which is a homologue of the FLP recombinase gene of 2-micron plasmid. An ARS region was identified, by replication in Saccharomyces cerevisiae and T. delbrueckii, near one of the inverted repeats. By the use of pTD1 derivatives and auxotrophic mutant hosts an efficient host-vector system was established for T. delbrueckii. So far, the 2-micron family of plasmids is restricted to four closely related genera (Q6 group): Saccharomyces, Zygosaccharomyces, Kluyveromyces, and Torulaspora. After a survey of 2500 strains belonging to about 500 species (80 genera) of yeast, no circular plasmids were found in other genera.
Asunto(s)
Ascomicetos/genética , ADN de Hongos , Plásmidos , Secuencia de Bases , Clonación Molecular , Replicación del ADN , Frecuencia de los Genes , Vectores Genéticos , Datos de Secuencia MolecularRESUMEN
Explores the tensions between cost and quality, need and market, and the effects on patient care and service providers within today's NHS. Builds on research carried out in two hospitals during 1993 to 1995, focusing on perceptions of quality and its management in the context of the nursing discipline. Indicates a divergence of perspectives on "customer requirements" and the emergence of a cultural divide within the total care process. Identifies and illustrates the significant potential for cost savings in health care, which may be achievable while simultaneously improving quality, and suggests that the "prize" for bridging the cultural divide might include a substantial financial gain as well as improved standards of care. In the context of health care, need, expectation, and finite resources are inextricably linked. A shared understanding of the interdependence between the three, and of the balance to be struck, is essential in health care provision today and into the twenty-first century. Suggests that there is some way to go.
Asunto(s)
Hospitales Públicos/normas , Gestión de la Calidad Total , Actitud del Personal de Salud , Ahorro de Costo , Investigación sobre Servicios de Salud , Costos de Hospital , Hospitales Públicos/economía , Humanos , Personal de Enfermería en Hospital/psicología , Personal de Enfermería en Hospital/estadística & datos numéricos , Cultura Organizacional , Medicina Estatal/economía , Medicina Estatal/organización & administración , Medicina Estatal/normas , Gestión de la Calidad Total/economía , Gestión de la Calidad Total/estadística & datos numéricos , Reino UnidoRESUMEN
Linear DNA plasmids were found in the following yeasts: four strains of Kluyveromyces lactis, one of Debaryomyces hansenii, one of Wingea robertsiae and four of Pichia etchellsii. In each case, the plasmids were present as a pair of DNA molecules of different sizes. The plasmids of K. lactis strains were associated with a killer activity and their structure was similar to the known killer plasmids pGKL1 and 2. The plasmids from the other three species were different from pGKL plasmids and showed no killer activity against the yeast species tested so far. In all cases, the linear molecules possessed terminal (probably inverted) repeats and their 5' ends had a protected structure insensitive to lambda exonuclease, while the 3' ends were accessible to exonuclease III. All these strains could be efficiently cured of the plasmids by ultraviolet irradiation. The plasmids from D. hansenii (pDH1A and B) and from W. robertsiae (pWR1A and B) shared related sequences with some of the K. lactis killer plasmid genes (encoding the supposed DNA polymerases, RNA polymerase and the chitinase), suggesting related genome organization of these plasmids. The pair of plasmids from P. etchellsii (pPE1A and B) appear to be a distantly related member of the group. This pair showed no sequence homology with other plasmids, except weak homology with the putative RNA polymerase gene of pGKL2. None of the plasmids contained the sequences homologous to ORF3 and ORF4 of pGKL1 encoding the toxin resistance determinant and the toxin gamma subunit, respectively.
Asunto(s)
ADN de Hongos/genética , Micotoxinas/genética , Plásmidos/genética , Levaduras/genética , Genes Fúngicos , Factores Asesinos de Levadura , Kluyveromyces/genética , Kluyveromyces/ultraestructura , Micotoxinas/farmacología , Pichia/genética , Pichia/ultraestructura , Secuencias Repetitivas de Ácidos Nucleicos , Mapeo Restrictivo , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie , Levaduras/efectos de los fármacos , Levaduras/ultraestructuraRESUMEN
A distributed Microbial Information Network Europe (MINE) is being constructed by a number of major microbial culture collections in countries of the European Community, with the support of the Biotechnology Action Programme (BAP) of the Commission of the European Community. The representatives of the collections participating in MINE have agreed to adopt a general format for the computer storage and retrieval of strain data. This uniform format will facilitate the electronic combination and exchange of data from different collections in order to produce integrated catalogues and the use of identical commands to search the different databases. It is recommended to other collections who may wish to contribute data to the MINE network or between themselves. Three kinds of records can be linked to the leading 'species records': strain records, synonym records, and alternative morphonym records. A minimum data set of 30 fields (similar to the fields used for producing catalogues) is defined that facilitates the exchange of data between the national nodes and serves as a directory to strains available at other nodes. It is suggested that the full strain record comprise 99 fields, grouped in 12 blocks: internal administration--name--strain administration--status--environment and history--biological interactions--sexuality--properties (cytology, biomolecular data)--genotype and genetics--growth conditions--chemistry and enzymes--practical applications. Several fields are divided into subfields of different ranks. Delimiters are used either to separate a range of entries that have to be indexed or to divide an entry from the reference to its source or remarks that should not be indexed. The contents and structure of the fields proposed for filamentous fungi and yeasts are described and in some cases illustrated by examples. Uniformity of input is essential for indexed fields and desirable for non-indexed fields. Seven thesaurus files are envisaged to ensure consistency.
Asunto(s)
Hongos , Sistemas de Información , Microbiología , Recolección de Datos/normas , Europa (Continente) , Registros , LevadurasRESUMEN
Type strains of 200 species of yeasts able to ferment glucose and grow on xylose were screened for fermentation of d-xylose. In most of the strains tested, ethanol production was negligible. Nineteen were found to produce between 0.1 and 1.0 g of ethanol per liter. Strains of the following species produce more than 1 g of ethanol per liter in the fermentation test with 2% xylose: Brettanomyces naardenensis, Candida shehatae, Candida tenuis, Pachysolen tannophilus, Pichia segobiensis, and Pichia stipitis. Subsequent screening of these yeasts for their capacity to ferment d-cellobiose revealed that only Candida tenuis CBS 4435 was a good fermenter of both xylose and cellobiose under the test conditions used.
RESUMEN
The yeast genera Endomyces, Endomycopsella, Guilliermondella and Saccharomycopsis are delimited by the size, structure and pigmentation of the ascospores; they include mycelial yeasts formerly classified in the invalid genus Endomycopsis. The ultrastructure of the cell wall and the septa of yeasts is briefly discussed.
Asunto(s)
Ascomicetos/clasificación , Saccharomycetales/clasificación , Basidiomycota/clasificación , Pared Celular/ultraestructura , Saccharomycetales/crecimiento & desarrollo , Saccharomycetales/ultraestructura , Esporas Fúngicas/ultraestructuraRESUMEN
Groups of taxa such as genera, or groups derived from some forms of cluster analysis, may have insufficient test results that are constant within the groups to allow diagnostic keys and tables to be constructed in the usual way. This paper describes how the usual methods can be adapted to allow construction based on information about the individual group members, instead of on the overall group information. A new key to the genera of yeasts is constructed by these modified methods.
Asunto(s)
Levaduras/clasificación , Computadores , MétodosRESUMEN
There strains representative of two undescribed Torulopsis species, T. geochares and T. azyma, were recovered from soil and rupicolous lichen in South Africa. Descriptions of the new species are given. Ploidy determinations by X-ray inactivation showed the type strains of the two new species to be haploid. On the basis of their affinitive characteristics the new species appear to be related to the ascomycetous yeasts.
Asunto(s)
Candida/clasificación , Microbiología del Suelo , Candida/genética , Candida/fisiología , Haploidia , SudáfricaRESUMEN
A new yeast species with basidiomycetous affinities is described as Candida sonckii Hopsu-Havu et al. It differs from C. fujisanensis and C. maris by growing with KNO3 as nitrogen source, from C. vanderwaltii by its lower mol% G + C, lower maximum temperature for growth and failure to grow on D-arabinose and citrate.
Asunto(s)
Candida/clasificación , Microbiología del Agua , Candida/fisiología , Terminología como AsuntoRESUMEN
A new yeast species Pichia norvegensis Leask et Yarrow is described as the perfect state of Candida norvegensis (Dietrichson) van Uden et Farinha ex van Uden et Buckley. Strains of this species were isolated on 3 occasions from human vaginas. This species differs from other Pichia species that assimilate glucose but not galactose, sucrose, maltose, lactose, D-mannitol and D-glucitol by assimilating cellobiose.
Asunto(s)
Ascomicetos/clasificación , Pichia/clasificación , Femenino , Humanos , Pichia/crecimiento & desarrollo , Pichia/metabolismoRESUMEN
Selected yeast classified as Candida sake van Uden et Buckley were examined for their physiological, morphological and immunological properties and their DNA relatedness. Candida maltosa Komagata, Nakase et Katsuya is herein recognized as a species separate from C. sake, Candida maltosa was distinguished from C. sake and from C. tropicalis by insignificant DNA reassociation. In addition, C. maltosa was distinguished from C. sake by its higher maximal growth temperature and lower guanine plus cytosine content of its DNA and from C. tropicalis by its failure to utilize soluble starch for growth and its resistance to cycloheximide. The species C. cloacae and C. subtropicalis are placed in synonymy with C. maltosa.
Asunto(s)
Candida/clasificación , Alcanos/metabolismo , Antígenos Fúngicos/análisis , Candida/inmunología , Candida/metabolismo , Metabolismo de los Hidratos de Carbono , Reacciones Cruzadas , Nucleótidos de Citosina/análisis , ADN/análisis , Epítopos , Fermentación , Nucleótidos de Guanina/análisis , Renaturación de Ácido Nucleico , Temperatura , Vitaminas/metabolismoRESUMEN
DNA base compositions (GC content) of Saccharomyces species are reported and discussed. Several amendments of the four groups given by van der Walt are suggested, viz. the transfer of S. kluyveri to group 1, and of S. eupagycus, S. cidri, S. montanus, S. microellipsodes and S. florentinus to group 2. The synonomy of S. amurcae and S. cidri is suggested. The DNA base compositions revealed two possible pairs of sibling species: S. elegans and S. bailii, with a difference in GC content of 4.1%; S. dairensis and S. servazzii with a difference in GC content of ca. 3%. S. mrakii had a GC content of 47.3-48.5% the highest encountered in this genus and similar to that of Kluyveromyces thermotolerans.
Asunto(s)
ADN/análisis , Saccharomyces/análisis , Citidina/análisis , Guanosina/análisis , Desnaturalización de Ácido Nucleico , Saccharomyces/clasificaciónRESUMEN
The determination of niacin in orange juice with lyophilized Lactobacillus arabinosus ATCC 8014 has the advantage over the usual method in eliminating the delay caused by the necessity of cultivating cells of L. arabinosus for the inoculum and also in eliminating the periodical cultivation on agar slopes.