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1.
Eur J Appl Physiol ; 118(10): 2171-2177, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30043183

RESUMEN

PURPOSE: Compression socks are frequently used in the treatment and prevention of lower-limb pathologies; however, when combined with endurance-based exercise, the impact of compression socks on haemostatic activation remains unclear. OBJECTIVES: To investigate the effect of wearing compression socks on coagulation and fibrinolysis following a marathon. METHODS: Sixty-seven participants [43 males (mean ± SD: age: 46.7 ± 10.3 year) and 24 females (age: 40.0 ± 11.0 year)] were allocated into a compression (SOCK, n = 34) or control (CONTROL, n = 33) group. Venous blood samples were obtained 24 h prior to and immediately POST-marathon, and were analyzed for thrombin-anti-thrombin complex (TAT), tissue factor (TF), tissue factor pathway inhibitor (TFPI), and D-Dimer. RESULTS: Compression significantly attenuated the post-exercise increase in D-Dimer compared to the control group [median (range) SOCK: + 9.02 (- 0.34 to 60.7) ng/mL, CONTROL: + 25.48 (0.95-73.24) ng/mL]. TF increased following the marathon run [median (range), SOCK: + 1.19 (- 7.47 to 9.11) pg/mL, CONTROL: + 3.47 (- 5.01 to 38.56) pg/mL] in all runners. No significant post-exercise changes were observed for TAT and TFPI. CONCLUSIONS: While activation of coagulation and fibrinolysis was apparent in all runners POST-marathon, wearing compression socks was shown to reduce fibrinolytic activity, as demonstrated by lower D-Dimer concentrations. Compression may reduce exercise-associated haemostatic activation when completing prolonged exercise.


Asunto(s)
Entrenamiento Aeróbico , Fibrinólisis , Carrera/fisiología , Medias de Compresión , Adulto , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad
2.
J Appl Microbiol ; 110(6): 1571-83, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21447014

RESUMEN

AIMS: Research into the relationship between pathogens, faecal indicator microbes and environmental factors in beach sand has been limited, yet vital to the understanding of the microbial relationship between sand and the water column and to the improvement of criteria for better human health protection at beaches. The objectives of this study were to evaluate the presence and distribution of pathogens in various zones of beach sand (subtidal, intertidal and supratidal) and to assess their relationship with environmental parameters and indicator microbes at a non-point source subtropical marine beach. METHODS AND RESULTS: In this exploratory study in subtropical Miami (Florida, USA), beach sand samples were collected and analysed over the course of 6 days for several pathogens, microbial source tracking markers and indicator microbes. An inverse correlation between moisture content and most indicator microbes was found. Significant associations were identified between some indicator microbes and pathogens (such as nematode larvae and yeasts in the genus Candida), which are from classes of microbes that are rarely evaluated in the context of recreational beach use. CONCLUSIONS: Results indicate that indicator microbes may predict the presence of some of the pathogens, in particular helminthes, yeasts and the bacterial pathogen Staphylococcus aureus including methicillin-resistant forms. Indicator microbes may thus be useful for monitoring beach sand and water quality at non-point source beaches. SIGNIFICANCE AND IMPACT OF THE STUDY: The presence of both indicator microbes and pathogens in beach sand provides one possible explanation for human health effects reported at non-point sources beaches.


Asunto(s)
Bacterias/aislamiento & purificación , Playas , Monitoreo del Ambiente/métodos , Helmintos/aislamiento & purificación , Microbiología del Agua , Levaduras/aislamiento & purificación , Animales , Recuento de Colonia Microbiana , Florida , Agua de Mar/microbiología , Agua de Mar/parasitología , Dióxido de Silicio/análisis
3.
Harmful Algae ; 8(2): 196-211, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20046212

RESUMEN

As an alternative to traditional, morphology-based methods, molecular techniques can provide detection of multiple species within the HAB community and, more widely, the phytoplankton community in a rapid, accurate and simultaneous qualitative analysis. These methods require detailed knowledge of the molecular diversity within taxa in order to design efficient specific primers and specific probes able to avoid cross-reaction with non-target sequences. Isolates from Florida coastal communities were sequence-analyzed and compared with the GenBank database. Almost 44% of the genotypes obtained did not match any sequence in GenBank, showing the existence of a large and still unexplored biodiversity among taxa. Based on these results and on the GenBank database, we designed 14 species-specific probes and 4 sets of specific primers. Multiple simultaneous detection was achieved with a bead array method based on the use of a flow cytometer and color-coded microspheres, which are conjugated to the developed probes. Following a parallel double PCR amplification, which employed universal primers in a singleplex reaction and a set of species-specific primers in multiplex, detection was performed in a cost effective and highly specific analysis. This multi-format assay, which required less than 4 h to complete from sample collection, can be expanded according to need. Up to 100 different species can be identified simultaneously in a single sample, which allows for additional use of this method in community analyses extended to all phytoplankton species. Our initial field trials, which were based on the 14 species-specific probes, showed the co-existence and dominance of two or more species of Karenia during toxic blooms in Florida waters.

4.
J Clin Microbiol ; 45(6): 1874-83, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17442792

RESUMEN

A Luminex suspension array, which had been developed for identification of Cryptococcus neoformans and Cryptococcus gattii isolates, was tested by genotyping a set of 58 mostly clinical isolates. All genotypes of C. neoformans and C. gattii were included. In addition, cerebrospinal fluid (CSF) obtained from patients with cryptococcal meningitis was used to investigate the feasibility of the technique for identification of the infecting strain. The suspension array correctly identified haploid isolates in all cases. Furthermore, hybrid isolates possessing two alleles of the Luminex probe region could be identified as hybrids. In CSF specimens, the genotype of the cryptococcal strains responsible for infection could be identified after optimization of the PCR conditions. However, further optimization of the DNA extraction protocol is needed to enhance the usability of the method in clinical practice.


Asunto(s)
Cryptococcus neoformans/clasificación , Cryptococcus/clasificación , Citometría de Flujo/métodos , Técnicas de Tipificación Micológica , Reacción en Cadena de la Polimerasa/métodos , Adulto , Anciano , Líquido Cefalorraquídeo/microbiología , Criptococosis/microbiología , Cryptococcus/genética , Cryptococcus/aislamiento & purificación , Cryptococcus neoformans/genética , Cryptococcus neoformans/aislamiento & purificación , ADN de Hongos/análisis , ADN de Hongos/aislamiento & purificación , Femenino , Genotipo , Humanos , Masculino , Meningitis Criptocócica/microbiología , Microesferas , Persona de Mediana Edad , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Especificidad de la Especie , Suspensiones
5.
Philos Trans R Soc Lond B Biol Sci ; 360(1462): 1897-903, 2005 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-16214747

RESUMEN

After the process of DNA barcoding has become well advanced in a group of organisms, as it has in the economically important fungi, the question then arises as to whether shorter and literally more barcode-like DNA segments should be utilized to facilitate rapid identification and, where applicable, detection. Through appropriate software analysis of typical full-length barcodes (generally over 500 base pairs long), uniquely distinctive oligonucleotide 'microcodes' of less than 25 bp can be found that allow rapid identification of circa 100-200 species on various array-like platforms. Microarrays can in principle fulfill the function of microcode-based species identification but, because of their high cost and low level of reusability, they tend to be less cost-effective. Two alternative platforms in current use in fungal identification are reusable nylon-based macroarrays and the Luminex system of specific, colour-coded DNA detection beads analysed by means of a flow cytometer. When the most efficient means of rapid barcode-based species identification is sought, a choice can be made either for one of these methodologies or for basic high-throughput sequencing, depending on the strategic outlook of the investigator and on current costs. Arrays and functionally similar platforms may have a particular advantage when a biologically complex material such as soil or a human respiratory secretion sample is analysed to give a census of relevant species present.


Asunto(s)
Biodiversidad , ADN/genética , Procesamiento Automatizado de Datos/métodos , Hongos/genética , Técnicas de Diagnóstico Molecular/métodos , Citometría de Flujo , Análisis por Micromatrices/métodos , Oligonucleótidos/genética , Especificidad de la Especie
6.
FEMS Yeast Res ; 2(4): 495-517, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12702266

RESUMEN

Basidiomycetous yeasts in the Urediniomycetes and Hymenomycetes were examined by sequence analysis in two ribosomal DNA regions: the D1/D2 variable domains at the 5' end of the large subunit rRNA gene (D1/D2) and the internal transcribed spacers (ITS) 1 and 2. Four major lineages were recognized in each class: Microbotryum, Sporidiobolus, Erythrobasidium and Agaricostilbum in the Urediniomycetes; Tremellales, Trichosporonales, Filobasidiales and Cystofilobasidiales in the Hymenomycetes. Bootstrap support for many of the clades within those lineages is weak; however, phylogenetic analysis provides a focal point for in-depth study of biological relationships. Combined sequence analysis of the D1/D2 and ITS regions is recommended for species identification, while species definition requires classical biological information such as life cycles and phenotypic characterization.


Asunto(s)
Basidiomycota/clasificación , ADN Espaciador Ribosómico/análisis , ADN Ribosómico/genética , Variación Genética , Basidiomycota/genética , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Filogenia , Análisis de Secuencia de ADN
7.
J Sci Med Sport ; 4(2): 188-95, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11548918

RESUMEN

The physiological profiles of 17 open grade (OG) and 13 reserve grade (RG) male surfboat rowers (SBR) aged 19-44 years were determined and compared. Parameters investigated included anthropometry, agility, isometric strength, flexibility, rowing ergometer performance (MT), peak VO2 and arterialised blood pH, lactate and bicarbonate. Means were compared using t-tests. Multiple regression analyses provided a number of models for the prediction of MT performance in SBR. The mean age, height, mass, and sum of eight skinfolds for SBR are: 26.2 (+/-5.9) years, 180.5 (+/-6.0) cm, 84.4 (+/-9.3) kg and 78.2 (+/-26.2) mm respectively. OG rowers were significantly different from RG for the parameters of ergometer performance (OG: 1360.2+/-42.9 m; RG: 1316.4+/-41.8 m), peak ventilation (OG: 174.2+/-17.2 L x min(-1); RG: 154.8+/-22.1 L x min(-1)), and post exercise blood pH levels (OG: 6.98+/-0.07; RG: 7.04+/-0.07). Performance on a rowing ergometer successfully discriminates between OG and RG rowers with the best predictors of ergometer performance in SBR being height, peak ventilation, and post exercise pH.


Asunto(s)
Ejercicio Físico/fisiología , Deportes/fisiología , Equilibrio Ácido-Base , Adulto , Antropometría , Australia , Bicarbonatos/sangre , Ergometría/instrumentación , Humanos , Ácido Láctico/sangre , Modelos Logísticos , Masculino , Músculo Esquelético/fisiología , Consumo de Oxígeno , Docilidad , Navíos , Análisis y Desempeño de Tareas
8.
Int J Syst Evol Microbiol ; 51(Pt 2): 687-697, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11321116

RESUMEN

The phenotypic and genetic heterogeneity of the basidiomycetous yeast species Rhodosporidium kratochvilovae was investigated in a group of recent isolates and collection strains. A polyphasic taxonomic approach was followed which included micromorphological studies, nuclear staining, determination of sexual compatibility, physiological characterization, comparison of electrophoretic isoenzyme patterns, PCR fingerprinting, determination of mol% G+C, DNA-DNA reassociation experiments and 26S and ITS rDNA sequence analysis. The results allowed a more natural circumscription of the species, both from the genetic and phenotypic perspectives. The relationships with anamorphic species of the genus Rhodotorula were studied and isolates previously identified as Rhodotorula glutinis were found to belong to Rhodosporidium kratochvilovae. Other isolates included in the study were found to represent members of Rhodotorula glutinis var. dairenensis. Rhodosporidium kratochvilovae was found to include heterothallic strains, besides those already known to be self-sporulating. A total of 17 isolates, which were found to belong to this species, were heterothallic, self-sporulating and anamorphic strains. It is anticipated that integrated polyphasic studies of basidiomycetous yeasts will provide a more coherent classification system and the basis for accurate identification schemes, which in turn are essential for detailed ecological studies.


Asunto(s)
Basidiomycota/clasificación , Levaduras/clasificación , Basidiomycota/citología , Basidiomycota/genética , Dermatoglifia del ADN , ADN de Hongos , Técnicas de Tipificación Micológica , Hibridación de Ácido Nucleico , Filogenia , Reacción en Cadena de la Polimerasa , Reproducción , Levaduras/citología , Levaduras/genética
9.
FEMS Yeast Res ; 1(1): 15-22, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12702459

RESUMEN

Several isolates representing the genus Trichosporon were collected over a 6-year period from soils in The Netherlands. Based on classical growth tests with carbon and nitrogen compounds these were identical. Three of these (CBS 8396, CBS 8397 and CBS 8522) were subjected to molecular analysis of the D1/D2 region of the large subunit of rDNA. This confirmed that the three strains were identical, yet distinct from other members of the genus. Conspecificity was demonstrated with the type strain (CBS 2040) of Apiotrichum porosum Stautz (1931), with the exception that A. porosum, which had been isolated from exudate of a yew tree, differed morphologically from the soil strains. Based on the identity of DNA base sequences, morphology was not considered to be an adequate parameter to separate otherwise identical strains into two genera. Therefore, the new combination Trichosporon porosum is presented. Based on molecular sequence analysis, T. porosum may be related to T. sporotrichoides, within a weakly related clade that includes species such as Trichosporon laibachii and Trichosporon loubieri. The strains of T. porosum degrade phenolic compounds and hemicelluloses, which are characteristics with potential ecological importance in soil habitats. Characters distinguishing the nine species of the laibachii/loubieri group of species were listed. These include traditionally used tests as well as assimilation patterns of some aliphatic and phenolic compounds. Based on these tests, species such as Trichosporon multisporum and T. laibachii could be separated.


Asunto(s)
Fenoles/metabolismo , Polisacáridos/metabolismo , Microbiología del Suelo , Trichosporon/clasificación , ADN de Hongos/análisis , ADN Ribosómico/análisis , Datos de Secuencia Molecular , Técnicas de Tipificación Micológica , Fenotipo , Filogenia , Análisis de Secuencia de ADN , Especificidad de la Especie , Trichosporon/genética , Trichosporon/aislamiento & purificación , Trichosporon/fisiología
10.
Antonie Van Leeuwenhoek ; 77(4): 355-8, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10959564

RESUMEN

Sequence analysis of the D1/D2 domains of the large subunit rDNA of Cryptococcus yarrowii (CBS 7417) indicates that this species does not belong to the hymenomycetous fungi, but instead is of urediniomycetous affinity. Therefore, the name change Rhodotorula yarrowii comb. nov. is proposed. The cell wall of the species contains xylose, a character considered by most authors to indicate fungi of hymenomycetous affinity. However, our results show that xylose may occur in minor amounts in the cell walls of urediniomycetous fungi. A high mannose content of the cell walls may be a more reliable character for urediniomycetous yeasts.


Asunto(s)
Basidiomycota/clasificación , Cryptococcus/clasificación , Rhodotorula/clasificación , Basidiomycota/genética , Pared Celular/química , Cryptococcus/genética , ADN Ribosómico/genética , Manosa/análisis , Filogenia , Rhodotorula/genética , Análisis de Secuencia de ADN , Xilosa/análisis
11.
Int J Syst Evol Microbiol ; 50 Pt 3: 1351-1371, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10843082

RESUMEN

The molecular systematics of 337 strains of basidiomycetous yeasts and yeast-like fungi, representing 230 species in 18 anamorphic and 24 teleomorphic genera, was determined by sequence analysis of the D1/D2 region of the large-subunit rDNA. The data were compared with published sequences of other basidiomycetous fungi. The results demonstrated that the yeast species and genera are phylogenetically distributed among the Microbotryum, Sporidiobolus, Agaricostilbum and Erythrobasidium clades of the Urediniomycetes; the Tremellales, Trichosporonales ord. nov., Filobasidiales and Cystofilobasidiales clades of the Hymenomycetes; and the Ustilaginales, Microstromatales and Malasseziales clades of the Ustilaginomycetes. Genera such as Bensingtonia, Cryptococcus, Rhodotorula and Sporobolomyces are polyphyletic, i.e. they occur in two or more clades. In contrast, other genera, e.g. Bullera, Cystofilobasidium, Fellomyces, Filobasidiella, Filobasidium, Kondoa, Kurtzmanomyces, Leucosporidium, Rhodosporidium, Sporidiobolus and Udeniomyces, are monophyletic. The majority of the species can be identified using D1/D2 analyses, although the internal transcribed spacer region is required to distinguish closely related species. The intergenic spacer region is recommended for additional differentiation of species and strains.


Asunto(s)
Basidiomycota/clasificación , ADN Ribosómico/genética , Variación Genética , ARN Ribosómico/genética , Basidiomycota/genética , ADN de Hongos/genética , Ecosistema , Filogenia , Análisis de Secuencia de ADN
12.
Int J Syst Evol Microbiol ; 50 Pt 1: 381-387, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10826826

RESUMEN

A morphological and physiological description of an alkane-assimilating anamorphic basidiomycetous yeast species, named Trichosporon veenhuisii, is presented. The ability to assimilate several aliphatic and aromatic compounds as sole source of carbon and energy is reported. The phylogenetic position within the genus, based on nuclear base sequencing of the D1/D2 region of the large subunit of rDNA, is discussed. The type strain is CBS 7136T.


Asunto(s)
Alcanos/metabolismo , Trichosporon/clasificación , Animales , Carbono/metabolismo , ADN de Hongos/genética , ADN Ribosómico/genética , Datos de Secuencia Molecular , Técnicas de Tipificación Micológica , Nitrógeno/metabolismo , Filogenia , Análisis de Secuencia de ADN , Trichosporon/citología , Trichosporon/crecimiento & desarrollo , Trichosporon/metabolismo
13.
Int J Syst Evol Microbiol ; 50 Pt 1: 389-394, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10826827

RESUMEN

An undescribed anamorphic yeast species of ascomycetous affinity, for which the name Candida tartarivorans is proposed, was isolated from dried wine lees in Portugal using a selective medium with L(+)-tartaric acid as the sole source of carbon and energy. The single isolate (IGC 4854T) showed the following characteristics: sympodial holoblastic conidiogenesis, absence of asci with ascospores, a negative colour reaction with Diazonium Blue B, production of elaborate pseudomycelium and ability to grow with inositol as sole source of carbon. Analysis of the physiological data pointed to a close relationship with other inositol-assimilating taxa, namely the genera Arxula, Stephanoascus, Sympodiomyces, Zygoascus and selected Candida species. Comparative analysis of the D1/D2 variable domain of the 26S rRNA gene of all available sequences for ascomycetous yeasts showed that strain IGC 4854T did not match with any other species in the database. The closest relative was Candida auringiensis Santa Maria, but the two species differed in 24 nucleotide positions. A description of the new species is given.


Asunto(s)
Candida/clasificación , Tartratos/metabolismo , Candida/genética , Candida/metabolismo , Candida/fisiología , ADN de Hongos/genética , ADN Ribosómico/genética , Datos de Secuencia Molecular , Técnicas de Tipificación Micológica , Filogenia , ARN Ribosómico/genética , Análisis de Secuencia de ADN , Vino/microbiología
14.
Antonie Van Leeuwenhoek ; 77(2): 153-7, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10768474

RESUMEN

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-Xilosidasa
15.
Can J Microbiol ; 46(1): 7-27, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10696468

RESUMEN

Evidence accumulated from studies based on physiological, biochemical, and molecular characteristics has pointed to the heterogeneity of the ubiquitous anamorphic basidiomycetous yeast species Cryptococcus albidus (Saito) Skinner, with its current varieties and synonyms. The taxonomic status of this species has not been reappraised because different studies, mostly involving limited numbers of strains, have not been integrated. To assess species diversity within the clade containing Cryptococcus albidus and other phylogenetically related Cryptococcus and Filobasidium species, we determined ribosomal DNA (rDNA) sequences of 69 strains from the 5' end of the 26S gene, D1/D2 region, and in some cases, the non-coding ITS2 region. Analysis of the sequence data together with available physiological, biochemical, and molecular characteristics, showed the segregation of C. albidus into at least 12 species, leading to the elevation of former varieties to the rank of species (C. aerius, C. diffluens), the reinstatement of synonyms (C. liquefaciens, C. terricola), and the proposal of new species (C. arrabidensis, C. chernovii, C. cylindricus, C. oeirensis, C. phenolicus, C. saitoi, C. uzbekistanensis, C. wieringae). The overall analyses of the results argue in favour of the use of rDNA sequence data to improve species delineation when integrated with other available physiological and molecular characteristics.


Asunto(s)
Cryptococcus/clasificación , ADN de Hongos/análisis , ADN Ribosómico/análisis , Variación Genética , Basidiomycota/clasificación , Basidiomycota/citología , Basidiomycota/genética , Cryptococcus/citología , Cryptococcus/genética , Filogenia , Análisis de Secuencia de ADN , Terminología como Asunto
16.
Antonie Van Leeuwenhoek ; 77(1): 7-12, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10696872

RESUMEN

Species of the genus Mrakia are currently classified as synonyms based on molecular sequence analyses of the large sub-unit ribosomal DNA (LrDNA). Physiological and protein electrophoretic studies, however, reveal possible species differences. To clarify this discrepancy, we undertook molecular sequence analyses of the internal transcribed spacer (ITS) and intergenic spacer (IGS) regions of rDNA from the four psychrophilic Mrakia species and the psychrophilic yeast, Cryptococcus curiosus. Identical ITS sequences were found between C. curiosus, M. nivalis and M. frigida. Although, M. stokesii and M. gelida displayed identical ITS and IGS sequences, their sequences differed from the other three species by 2.3% and 38%, respectively. The results suggest that M. stokesii is a synonym of M. gelida, whereas M. nivalis is a synonym of M. frigida. Sequence differences (1.9%) observed in the IGS region indicates that C. curiosus is a distinct strain of M. frigida.


Asunto(s)
Basidiomycota/clasificación , ADN de Hongos/genética , ADN Ribosómico/genética , Secuencia de Bases , Basidiomycota/genética , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia
17.
Syst Appl Microbiol ; 23(4): 535-45, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11249024

RESUMEN

The pathogen Crytococcus neoformans has been traditionally grouped in two varieties, C. neoforrmans var. neoformans (serotypes A, D and AD) and C. neoformans var. gattii (serotypes B and C). A recent taxonomic evaluation of C. neoformans var. neoformans described C. neoformans var. grubii as a new variety represented by serotype A isolates. Despite immunological, biochemical, ecological and molecular differences the three varieties are classified within one species. We examined the genetic variability of one hundred and five clinical and environmental isolates that included all varieties and serotypes. Sequence analysis of the intergenic spacer (IGS) associated with rDNA revealed significant differences in nucleotide composition between and within the varieties. Parsimony analysis showed five different genotypes representing distinct genetic lineages. Although there was a high degree of relatedness between serotype and genotype this relatedness was not exclusive as serotypes were not restricted to one particular genotypic group. Serotyping and sequence analyses indicate that C. neoformans var. grubii (serotype A) should not be recognized as a separate variety. Based on this study we propose to accept two separate species, C. neoformans (serotypes A, D and AD) and C. bacillisporus (serotypes B and C synonymous with C. neoformans var. gattii).


Asunto(s)
Cryptococcus neoformans/clasificación , ADN Intergénico/genética , ADN Ribosómico/genética , Criptococosis/microbiología , Cryptococcus neoformans/genética , Cryptococcus neoformans/aislamiento & purificación , Cryptococcus neoformans/fisiología , ADN de Hongos/genética , ADN Intergénico/análisis , ADN Intergénico/clasificación , ADN Ribosómico/análisis , ADN Ribosómico/clasificación , Variación Genética , Genotipo , Humanos , Filogenia , Alineación de Secuencia , Homología de Secuencia de Ácido Nucleico , Serotipificación , Programas Informáticos
18.
Antonie Van Leeuwenhoek ; 77(3): 293-302, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15188895

RESUMEN

The genus Kondoa Y. Yamada, Nakagawa & Banno was erected to accommodate a single taxon, K. malvinella (Fell & Hunter) Y. Yamada, Nakagawa & Banno, which was transferred from the teliospore-forming genus Rhodosporidium Banno based on pronounced differences in the 5S and 26S ribosomal RNA (rRNA) nucleotide sequences to R. toruloides Banno. In contrast with the original description, reinvestigation of K. malvinella revealed the formation of transversely septate (auricularioid) basidia that did not arise on teliospores, but formed directly on the dikaryotic mycelium. The four-celled basidia developed sterigmata on which forcibly discharged asymmetric basidiospores (ballistospores) were produced. Additionally, a new taxon emerged from the study of recent isolates, for which the name K. aeria sp. nov. is proposed. This new species produced two-celled auricularioid basidia on hyphae with incomplete clamp connections. Ballistospores arose on the basidia at the tip of sterigmata and, after ejection, germinated by budding. These observations led us to present an emended diagnosis for the genus Kondoa. Analysis of the sequence data from the D1/D2 region of the 26S rRNA gene showed a very close resemblance between K. aeria and K. malvinella in a cluster that also contained several Bensingtonia species. Taxa in this cluster share specific physiological traits and produce characteristic pinkish-cream to mauve colonies; in contrast, formation of ballistoconidia is only observed in the Bensingtonia species. Sequence data supported placement of K. malvinella and K. aeria in the 'Agaricostilbum clade' of the Urediniomycetes.


Asunto(s)
Basidiomycota/clasificación , Aminoácidos/metabolismo , Basidiomycota/citología , Basidiomycota/genética , Basidiomycota/metabolismo , Metabolismo de los Hidratos de Carbono , Análisis por Conglomerados , ADN de Hongos/química , ADN de Hongos/aislamiento & purificación , ADN Ribosómico/química , ADN Ribosómico/aislamiento & purificación , Genes de ARNr/genética , Hifa/citología , Técnicas de Tipificación Micológica , Filogenia , Pigmentos Biológicos/biosíntesis , Reacción en Cadena de la Polimerasa , ARN Ribosómico/genética , Análisis de Secuencia de ADN , Homología de Secuencia , Esporas Fúngicas/citología
19.
Can J Microbiol ; 45(8): 686-90, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10528400

RESUMEN

A morphological and physiological description of an anamorphic basidiomycetous yeast species, named Trichosporon guehoae (CBS 8521T), is presented. The ability to assimilate several aliphatic and aromatic compounds as sole source of carbon and energy is reported. The phylogenetic position within the genus, based on nuclear base sequencing of the D1/D2 region of the large subunit of rDNA is discussed.


Asunto(s)
Trichosporon/clasificación , ADN de Hongos/genética , ADN Ribosómico/genética , Datos de Secuencia Molecular , Técnicas de Tipificación Micológica , Filogenia , Análisis de Secuencia de ADN , Terminología como Asunto , Trichosporon/citología , Trichosporon/genética , Trichosporon/fisiología
20.
J Ind Microbiol Biotechnol ; 23(1): 677-81, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10455500

RESUMEN

The type strains of the anamorph Phaffia rhodozyma (CBS 5905) and the teleomorph Xanthophyllomyces dendrorhous (VKM Y-2786) were analyzed by nucleotide sequence analysis and compared to the sequences found in three additional strains (ATCC 24228, ATCC 24230 and CBS 6938). The results of ribosomal DNA Internal transcribed spacer (ITS) and Intergenic spacer (IGS) region analyses indicate that P. rhodozyma, which was isolated from a beech tree, is a distinct species from the other four strains. The latter that were collected from birch trees are considered to be strains of X. dendrorhous. These individual strains of X. dendrorhous, which have geographically distinct isolation sources, can be distinguished by nucleotide substitutions and deletion/insertion gaps in sub-repeat regions of the Intergenic spacer. The conclusions demonstrate that differences in the IGS region provide molecular markers for denoting strains that may differ in their biochemical and physiological capabilities. The hypothesis is presented that strain differences in the IGS region may be useful to demonstrate geographic and host specificity.


Asunto(s)
Basidiomycota/genética , ADN Espaciador Ribosómico/genética , Secuencia de Bases , Basidiomycota/química , Basidiomycota/clasificación , ADN Espaciador Ribosómico/química , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Homología de Secuencia de Ácido Nucleico
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