RESUMEN
Several independent surveys of yeasts associated with different plant materials and soil led to the proposal of a novel yeast species belonging to the Tremellales clade (Agaricomycotina, Basidiomycota). Analysis of the sequences of the D1/D2 domains and internal transcribed spacer region of the large subunit of the rRNA gene suggested affinity to a phylogenetic lineage that includes Hannaella coprosmaensis, Hannaella oryzae and Hannaella sinensis. Thirty-two isolates were obtained from different sources, including bromeliads, nectar of Heliconia psittacorum (Heliconiaceae), flowers of Pimenta dioica (Myrtaceae), roots and leaves of sugar cane (Saccharum spp.) in Brazil, leaves of Cratoxylum maingayi, Arundinaria pusilla and Vitis vinifera in Thailand, soil samples in Taiwan, and prairie soil in the USA. Sequence analysis of the D1/D2 domains of the large subunit of the rRNA gene showed that the novel species differs from Hannaella coprosmaensis and Hannaella oryzae by 36 and 46 nt substitutions, respectively. A novel species is suggested to accommodate these isolates, for which the name Hannaella pagnoccae sp. nov. is proposed. The type strain is BI118(T) (â=âCBS 11142(T)â=âATCC MYA-4530(T)).
Asunto(s)
Basidiomycota/clasificación , Heliconiaceae/microbiología , Myrtaceae/microbiología , Filogenia , Saccharum/microbiología , Microbiología del Suelo , Secuencia de Bases , Basidiomycota/genética , Basidiomycota/aislamiento & purificación , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Flores/microbiología , Datos de Secuencia Molecular , Técnicas de Tipificación Micológica , Hojas de la Planta/microbiología , Raíces de Plantas/microbiología , Análisis de Secuencia de ADN , TaiwánRESUMEN
Emerging infectious diseases usually arise from wild animal populations. In the present work, we performed a screening for bacterial infection in natural populations of New World primates. The blood cell bulk DNAs from 181 individuals of four Platyrrhini genera were PCR screened for eubacterial 16S rRNA genes. Bacteria were detected and identified in 13 distinct individuals of Alouatta belzebul, Alouatta caraya, and Cebus apella monkeys from geographically distant regions in the states of Mato Grosso and Pará, Brazil. Sequence analyses showed that these Platyrrhini bacteria are closely related not only to human pathogens Pseudomonas spp. but also to Pseudomonas simiae and sheep-Acari infecting Pseudomonas spp. The identified Pseudomonas possibly represents a group of bacteria circulating in natural monkey populations.
Asunto(s)
Bacterias/aislamiento & purificación , Infecciones Bacterianas/veterinaria , Haplorrinos/microbiología , Enfermedades de los Primates/microbiología , Animales , Animales Salvajes/microbiología , Bacterias/clasificación , Bacterias/genética , Infecciones Bacterianas/microbiología , Haplorrinos/clasificación , Humanos , Datos de Secuencia Molecular , FilogeniaRESUMEN
Two novel yeast species, Candida aechmeae sp. nov. and Candida vrieseae sp. nov., were isolated from bromeliads in Itapuã Park, Rio Grande do Sul, Brazil. These species are genetically isolated from all other currently recognized ascomycetous yeasts based on their sequence divergence in the D1/D2 domain of the LSU rRNA gene. C. aechmeae sp. nov. is phylogenetically close to Candida ubatubensis, a species also isolated from bromeliads in Brazil, but the novel species can be differentiated on the basis of differences in the D1/D2 domain and positive results for the assimilation of l-arabinose, raffinose, inulin and citrate. Candida vrieseae sp. nov. is phylogenetically placed in a clade near Candida membranifaciens that is composed of several species associated with insects, but the novel species can be differentiated from them by the D1/D2 and ITS gene sequences, positive results for the assimilation of nitrite and a negative result for the assimilation of ethylamine. The type strain for Candida aechmeae sp. nov. is BI153(T) (=CBS 10831(T)=NRRL Y-48456(T)) and the type strain for C. vrieseae sp. nov. is BI146(T) (=CBS 10829(T)=NRRL Y-48461(T)).
Asunto(s)
Bromelia/microbiología , Candida/clasificación , Candida/aislamiento & purificación , Brasil , Candida/genética , Candida/metabolismo , ADN de Hongos/genética , ADN Ribosómico/genética , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genéticaRESUMEN
Nutrition in the Teredinidae family of wood-boring mollusks is sustained by cellulolytic/nitrogen fixing symbiotic bacteria of the Teredinibacter clade. The mangrove Teredinidae Neoteredo reynei is popularly used in the treatment of infectious diseases in the north of Brazil. In the present work, the symbionts of N. reynei, which are strictly confined to the host's gills, were conclusively identified as Teredinibacter turnerae. Symbiont variants obtained in vitro were able to grow using casein as the sole carbon/nitrogen source and under reduced concentrations of NaCl. Furthermore, cellulose consumption in T. turnerae was clearly reduced under low salt concentrations. As a point of interest, we hereby report first hand that T. turnerae in fact exerts antibiotic activity. Furthermore, this activity was also affected by NaCl concentration. Finally, T. turnerae was able to inhibit the growth of Gram-negative and Gram-positive bacteria, this including strains of Sphingomonas sp., Stenotrophomonas maltophilia, Bacillus cereus and Staphylococcus sciuri. Our findings introduce new points of view on the ecology of T. turnerae, and suggest new biotechnological applications for this marine bacterium.
RESUMEN
Nutrition in the Teredinidae family of wood-boring mollusks is sustained by cellulolytic/nitrogen fixing symbiotic bacteria of the Teredinibacter clade. The mangrove Teredinidae Neoteredo reynei is popularly used in the treatment of infectious diseases in the north of Brazil. In the present work, the symbionts of N. reynei, which are strictly confined to the host's gills, were conclusively identified as Teredinibacter turnerae. Symbiont variants obtained in vitro were able to grow using casein as the sole carbon/nitrogen source and under reduced concentrations of NaCl. Furthermore, cellulose consumption in T. turnerae was clearly reduced under low salt concentrations. As a point of interest, we hereby report first hand that T. turnerae in fact exerts antibiotic activity. Furthermore, this activity was also affected by NaCl concentration. Finally, T. turnerae was able to inhibit the growth of Gram-negative and Gram-positive bacteria, this including strains of Sphingomonas sp., Stenotrophomonas maltophilia, Bacillus cereus and Staphylococcus sciuri. Our findings introduce new points of view on the ecology of T. turnerae, and suggest new biotechnological applications for this marine bacterium.
Asunto(s)
Bacterias , Moluscos/fisiología , Simbiosis , Biotecnología , Brasil , Carbono , NitrógenoRESUMEN
The Heteroduplex Mobility Assay (HMA) method using the PCR amplified D1/D2 region of the 26S rDNA was tested for the differentiation of clinically relevant Candida species. Strains belonging to the same species are not expected to form heteroduplexes in this assay when their PCR products are mixed. D1/D2 HMA experiments between all Candida type strains tested showed heteroduplex formation, including Candida albicans and Candida dubliniensis. There was no heteroduplex formation when most clinical and non-type strains were tested against the type strain of their presumptive species, except when C. albicans WVE and C. dubliniensis TAI were analysed. Additional HMA experiments, phenotypic characterisation, and D1/D2 sequencing identified these isolates as Candida tropicalis and Candida parapsilosis, respectively. HMA provides a rapid and relatively simple molecular tool for the differentiation of potentially pathogenic Candida species.
Asunto(s)
Candida/clasificación , Candida/genética , ADN de Hongos/genética , ADN Ribosómico/genética , Análisis Heterodúplex/métodos , Secuencia de Bases , Candida/aislamiento & purificación , Candida albicans/clasificación , Candida albicans/genética , Candida albicans/aislamiento & purificación , Candida tropicalis/clasificación , Candida tropicalis/genética , Candida tropicalis/aislamiento & purificación , Cartilla de ADN/genética , ADN de Hongos/aislamiento & purificación , ADN Ribosómico/aislamiento & purificación , Humanos , ARN de Hongos/genética , ARN Ribosómico/genética , Especificidad de la EspecieRESUMEN
The internal transcribed spacer (ITS) region of rDNA was used for taxonomic inferences in ascomycetous yeasts. The Debaryomyces species had a 640-690 ITS size. The analyzed Candida species can be differentiated by its distinct ITS size. The enzymatic digestion of the ITS region show large homogeneity in Debaryomyces, with polymorphism for only two enzymes. The ITS size and the enzymatic restriction method were used in Brazilian isolates, detecting some Debaryomyces misidentifications in cultures previously identified by conventional methods.
RESUMEN
No presente trabalho nos analisamos a estrutura e a organizaçäo molecular dos genes ribossômicos em 9 espécies da família Culicidae. Os resultados obtidos com o uso de 3 enzimas de restriçäo demonstram que esses genes säo relativamente conservados nesse grupo de insetos. Quase nenhuma variaçäo intra-específica foi detectada nas 4 linhagens de uma espécie estudada, contrastando fortemente com os resultados conhecidos para os outros organismos. Os resultados demonstram que é possível usar enzimas de restriçäo para discriminar espécies nessa família de insetos
