Identificación taxonómica de hifomicetos acuáticos en la cuenca alta del río Bogotá (Colombia) a partir de muestras de espuma / Taxonomic identification of aquatic hyphomycetes in the upper Bogotá river basin (Colombia) from foam samples

Partiendo de que los hifomicetos u hongos ingoldianos son microorganismos presentes en los ambientes acuáticos como los ríos en los cuales intervienen en la descomposición del material orgánico devolviendo la energía a los niveles superiores de la cadena trófica, pero que a pesar de su importancia son pocos los estudios realizados referente a su diversidad y presencia en estos ecosistemas, el objetivo de este trabajo fue identificar los hifomicetos presentes en la cuenca alta del río Bogotá. Esto se realizó mediante la toma de muestra de espuma en los remansos de los ríos a las cuales se les realizó coloración con azul de lactofenol y observación con microscopio óptico para la identificación de los hongos ingoldianos a partir de la morfología de sus conidios con el uso de claves taxonómicas. Se identificaron un total de 10 géneros y 10 especies de las cuales 4 géneros y 7 especies son reportes nuevos para el territorio colombiano, lo cual demuestra la gran diversidad y desconocimiento que tenemos de estos microorganismos en nuestro país. (AU)

Based on the fact that hyphomycetes or ingoldian fungi are microorganisms present in aquatic environments such as rivers in which they are involved in the decomposition of organic material, returning energy to the higher levels of the trophic chain, but despite their importance, few studies have been conducted on their diversity and presence in these ecosystems, the objective of this work was to identify the hyphomycetes present in the upper Bogotá river basin. This was done by taking foam samples in the backwaters of the rivers, staining them with lactophenol blue and observing them with optical microscopy to identify the ingoldian fungi based on the morphology of their conidia with the use of taxonomic keys. A total of 10 genera and 10 species were identified, of which 4 genera and 7 species are new reports for the Colombian territory, which demonstrates the great diversity and lack of knowledge that we have of these microorganisms in our country. (AU)

Producción de carotenoides en levaduras nativas aisladas de sistemas acuáticos en Cali, Colombia / Carotenoids production in wild yeasts isolated from aquatic systems in Cali, Colombia

Introducción: Los carotenoides son fuente importante de actividades biológicas funcionales, tales como antioxidantes o antimicrobianas, además de tener gran impacto a nivel industrial, ya sea en cosmética o suplementación animal en acuacultura. Se han reportado varias moléculas novedosas a partir de aislamientos en Latinoamérica, principalmente en la Patagonia, Argentina. Sin embargo, no hay reportes en Colombia que evalúen la producción de carotenoides en levaduras nativas pigmentadas. Objetivo: Se evaluó la capacidad de producción de carotenoides en levaduras nativas aisladas de lagos, ríos y aguas residuales de la ciudad de Cali, Colombia. Materiales y métodos: Se caracterizaron 30 levaduras provenientes de dos colecciones. De estas se obtuvo su biomasa, rendimiento de carotenoides totales y producción de ß-caroteno. Las cepas promisorias fueron identificadas secuenciando la región ITS1-5.8S-ITS2. Resultados: El mayor rendimiento en la extracción de pigmentos se obtuvo para las cepas P11A (84,36 ± 5,24 µg/g) y Rhodotorula paludigena CS13 (56,26 ± 7,08 µg/g), mientras que las concentraciones más altas de ß-caroteno fueron 10,2 µg/mL (R. paludigena CS13) y 9,7 µg/mL (R. mucilaginosa/alborubescens P10A). La cinética de crecimiento y producción de pigmentos durante cinco días fue óptima para la cepa P11A, ya que hubo un aumento en el rendimiento de carotenoides totales 10 veces mayor (48 h: 109,62 µg/g, 120 h: 1403,10 µg/g). Conclusiones: En este estudio se encontró que levaduras aisladas de sistemas acuáticos son promisorias para la producción de pigmentos carotenoides (incluyendo ß-caroteno), siendo su extracción y caracterización viable para futuros estudios biotecnológicos.

Introduction: Carotenoids are an important source of biological activities, such as antioxidant or antimicrobial. Also, carotenoids impact the cosmetic or food supplement industry, mainly in aquaculture. Several reports in Latin America showed novel molecules, mainly in isolated strains in Patagonia, Argentina. However, in Colombia, there are not reports about carotenoid production from pigmented wild yeasts. Objective: We assessed the carotenoid production ability in wild yeasts isolated from lakes, wastewater and rivers located in Cali, Colombia. Materials and methods: 30 yeasts were selected from two collections, each of them was characterized by the biomass, yield of total carotenoids and ß-carotene production. Promisor strains were identified with sequence analysis of ITS1-5.8S-ITS2 region. The highest yield in pigment extraction was obtained by strains P11A (84,36 ± 5,24 µg/g) and Rhodotorula paludigena CS13 (56,26 ± 7,08 µg/g), while higher concentrations of ß-carotene were 10,2 µg/mL (R. paludigena CS13) and 9,7 µg/mL (R. mucilaginosa/alborubescens P10A). The kinetics of growth and pigment production for five days was optimal for the P11A strain, where we found an increasing 10-fold higher (48 h: 109,62 µg/g, 120 h: 1403,10 µg/g). Conclusions: We suggest that yeasts isolated from aquatic systems are promising for the production of carotenoid pigments (including ß-carotene), making their extraction and characterization viable for future biotechnological studies.

Chemical constituents of the fermentation broth of the marine-derived fungus Penicillium roqueforti / / Componentes químicos del caldo de fermentación del hongo de origen marino Penicillium roqueforti

Background. The filamentous fungus Penicillium roqueforti is a well-known multifunctional cell factory of high added-value biomolecules. Aims. The objective of this work was to carry out a detailed analysis of the metabolites present in the culture broth of a new marine-derived Penicillium roqueforti strain isolated in the Canary Islands, Spain. Methods. The fungal biomass production was carried out in liquid-state fermentation, and after 10-12 days of incubation at 22-25 °C, the supernatant mycelia was separated by filtration, and the culture broth (12 l) was stored in a refrigerator at 4 °C for a subsequent liquid–liquid extraction with dichloromethane (3×), in accordance with the modified Kupchan method. The volatile and semi-volatile organic compounds were separated by chromatography and analyzed using GC–MS and NMR spectroscopy analyses. Results. Several volatile organic compounds involved in the fatty acid pathway were identified: a terpenoid, a cyclic dipeptide, phthalates, and an alkyl adipate. In addition, three categories of non-volatile compounds (alkanes, fatty acids and 1-alkanols) were identified by spectroscopy. The results show that the fermented broth of this fungal strain has no mycotoxins under the culture conditions applied.Conclusions. It is hoped that this chemo-specific information will offer critical input for improving the biotechnological applications of this filamentous fungus (AU)

Antecedentes. El hongo filamentoso Penicillium roqueforti es una fábrica celular multifuncional de biomoléculas de alto valor añadido. Objetivos. El objetivo de este trabajo fue realizar un estudio minucioso de los metabolitos presentes en el caldo de cultivo de una nueva cepa de Penicillium roqueforti de origen marino aislada en las Islas Canarias, España. Métodos. La producción de biomasa fúngica se llevó a cabo por fermentación en estado líquido. Tras 10-12 días de incubación a 22-25 °C se separó el micelio sobrenadante por filtración y el caldo de cultivo (12 l) se almacenó en un frigorífico a 4 °C hasta su posterior extracción líquido-líquido con diclorometano (×3) de acuerdo con el método modificado de Kupchan. Los compuestos orgánicos volátiles y semi-volátiles se caracterizaron por GC-MS y análisis espectroscópico (NMR). Resultados. Se identificaron varios compuestos orgánicos volátiles implicados en la ruta de los ácidos grasos, un terpeno, un dipéptido cíclico, varios ftalatos y un adipato de alquilo. Además, fueron identificados por espectroscopía tres tipos de compuestos no volátiles: alcanos, ácido grasos y 1-alcanoles. Los resultados mostraron que el caldo fermentado de esta cepa fúngica no presenta micotoxinas en las condiciones de cultivo empleadas. Conclusiones. Es de esperar que esta información quimio-específica aporte datos críticos para el progreso de las aplicaciones biotecnológicas de este hongo filamentoso (AU)

Enhancement of chitosanase production by cell immobilization of Gongronella sp. JG

Chitosanase production of Gongronella sp. JG cells immobilized in calcium alginate gel and polyurethane foam was compared with that of the free cells, there was a 60% increase in the enzyme yield (2429 U/L) compared to the highest yield obtained from free cells (1513 U/L). The optimal immobilization parameters (concentrations of sodium alginate, calcium chloride, bead inoculums, bead diameter, etc) for the enhanced production of chitosanase were determined as: sodium alginate 2% (w/v), 0.1 M calcium chloride, inoculum 10 mL beads to 100 mL production media and 2.7 mm bead diameter. Maximum chitosanase production was achieved with initial pH of 5.5 and temperature of 30 ºC. The alginate beads had well stability, retained 85% ability of enzyme production even after 7 cycles of repeated batch fermentation. These results showed the immobilization technique was a feasible and economical method for chitosansase production by Gongronella sp. JG.

Rodentborne fungal pathogens in wetland agroecosystem

The past few decades have witnessed an overwhelming increase in the incidence of fungal infections, particularly in immunocompromised individuals. Consequently, zoonotic diseases, especially through rodents constitute a prominent group among the emerging diseases. Rodents are commensal to man and related health risks are common. Water rats (Rattus norvegicus) are typical to Vembanadu-Kol wetland agroecosystems, where they can act as a good carrier nexus for pathogens. The present study evaluates the carrier status of water rats with respect to fungal pathogens. A total of fifty two fungi covering eighteen families were isolated. Among the isolates, eight were dermaptophytes and Chrysosporium sp. (89.18%) was the frequent isolate. The source-wise analyses showed an increased isolation from ventral hair (67 isolates). Water rats of Vembanadu-Kol wetland agroecosystem are potent carrier of dermaptophytes and other opportunistic fungi, and strong carrier paths are existing too.

Isolation and cultivation of fungal strains from in vitro cell cultures of two marine sponges (Porifera: Halichondrida and Haplosclerida)

Despite the large number of reports describing sponge-microbe associations, limited knowledge is available about associated fungi and their relationships with the hosts. In this work, specific fungal strains were obtained directly from in vitro sponge cell cultures (primmorphs) and single sponge cells (cytospins) and compared with those obtained from whole tissue preparations. A total of 27 fungal strains were isolated from the marine sponges Hymeniacidon heliophila and Haliclona melana. Fifteen strains, nine from H. heliophila and six from H. melana, were obtained from whole tissue and were considered as possible mesohyl associated or transient fungi. Twelve strains were isolated from in vitro sponge cell cultures (primmorphs) and were, therefore, considered as cell associated. From these, five different strains were obtained from H. heliophila isolated cells, while five were identified from cytospins and two from primmorphs of H. melana. The fungal strains obtained from cell cultures from both sponge species were different, and none of them were detected in the whole tissue preparations of the same species. Nine H. heliophila and seven H. melana strains shows low similarity with the sequences available in public databases and belong to potentially new species. This is the first report of fungi isolated directly from sponge cells, which allowed the observation and selection of specific strains that probably would not be obtained by usual culture dependent techniques.

Isolation of Papulaspora halima and a new morphological variety of Halosphaeria tubulifera from seawater of potter cove (King George Island, South Shetland Island, Antarctica) / Aislamiento de Papulaspora halima y de una nueva variedad morfológica de Halosphaeria tubulifera desde agua de mar de Potter Cove (Isla Rey Jorge /25 de Mayo, islas Shetland del Sur, Antártida)

Marine fungi ascribed to the ascomycetes and the hyphomycetes are infrequently reported for the Southern Ocean. For this reason, the main objective of the present work was to detect the presence of these fungi seawater of Potter Cove, King George (25 de Mayo) Island, South Shetland Island, Antarctica. For this purpose marine fungi were grown on wood test panels, placed into plastic nets in the tidal zone, exposed to the Antarctic seawater for different periods of time, which ranged between 2 and 12 months.As a result of this survey, we were able to recover and identify two marine fungi, Papulospora halima (which represents the first report for this environment) and a new morphological variety of Halosphaeria tubulifera.

Los ascomicetes e hifomicetes marinos están escasamente documentados para el océano Atlántico Sur. Por este motivo, el principal objetivo del presente trabajo fue detectar la presencia de dichos hongos en las agua marinas de la Potter Cove, en la isla Rey Jorge/25 de Mayo (islas Shetland del Sur, Antártida). Para este propósito, los hongos marinos se desarrollaron en paneles de madera dentro de una red plástica en la zona tidal, expuestos al agua de mar antártica por diferentes períodos de tiempo que oscilaron entre 2 a 12 meses. Como resultado de este estudio, fuimos capaces de recuperar e identificar 2 hongos marinos, Papulospora halima (que representa el primer reporte para este ambiente) y una nueva variedad morfológica de Halosphaeria tubulifera.

Regulação da expressão gênica por oxigênio no fungo aquático Blastocladiella emersonii / Regulation of gene expression by oxygen in the aquatic fungus Blastocladiella emersonii

Neste trabalho realizamos a análise das variações na expressão gênica global do fungo aquático Blastocladiella emersonii submetido ao estresse de carência de oxigênio (hipóxia), utilizando a técnica de microarranjos de cDNA em lâminas contendo 3773 genes distintos. Nos experimentos de hipóxia gradual (diminuição gradual da concentração de oxigênio dissolvido, seguido de reoxigenação) e hipóxia direta (diminuição direta da concentração de oxigênio dissolvido, seguido de reoxigenação) observamos que 650 genes foram diferencialmente expressos em pelo menos uma das condições de estresse e que 534 deles mostraram-se afetados (direta ou indiretamente) pela disponibilidade de oxigênio, uma vez que apresentaram recuperação (ou tendência à recuperação) da sua expressão aos níveis normais, quando as células foram reoxigenadas. Além de modular a expressão de diversos genes sem função conhecida, B. emersonii responde à hipóxia reajustando a expressão de genes responsáveis pela produção e consumo de energia. Pelo menos transcricionalmente, este fungo favorece o metabolismo anaeróbico, através da indução de genes que codificam enzimas da via glicolítica e lactato desidrogenase, ao passo que no ciclo do ácido cítrico, a maioria dos genes encontram-se reprimidos ou não sofrem alteração na expressão. Processos dispendiosos em energia como síntese protéica, metabolismo de aminoácidos, enovelamento de proteínas e transporte por membrana apresentaram perfis predominantemente de repressão gênica quando em carência de oxigênio. Ainda utilizando a técnica de microarranjos, mostramos semelhanças entre os perfis transcricionais nos experimentos hipóxia e de carência de Fe2+ (tratamento com quelante de Fe2+ 2,2´-dipyridyl) sugerem que estes estresses estão de alguma forma relacionados, fornecendo bons indícios de que o íon Fe2+ possa ter um papel importante no mecanismo sensor de oxigênio e/ou de resposta a hipóxia em B. emersonii. Além disso, o tratamento prévio de células...

In this work we analyzed global gene expression changes in the aquatic fungus Blastocladiella emersonii submitted to oxygen deprivation (hypoxia), using cDNA microarrays containing 3,773 distinct genes. In gradual hypoxia (gradual decrease in dissolved oxygen concentration, followed by reoxygenation) and direct hypoxia (direct decrease of dissolved oxygen concentration, followed by reoxygenation) we observed 650 differentially expressed genes in at least one of the stress conditions tested, 534 of them being affected (directly or indirectly) by oxygen availability, since they showed recovery of normal expression levels or a tendency to recover, when cells were reoxygenated. Besides modulating many genes with no previously assigned function, B. emersonii responds to hypoxia by readjusting the expression levels of genes responsible for energy production and consumption. At least transcriptionally, this fungus seems to favour anaerobic metabolism through the induction of genes encoding glycolytic enzymes and lactate dehydrogenase, while in the TCA-cycle, most genes were repressed or unchanged. Energy-costly processes like protein synthesis, amino acid metabolism, protein folding and transport had their gene expression profiles predominantly repressed during oxygen deprivation. Microarray experiments also showed similarities between the transcriptional profile of genes in hypoxia and iron (II) deprivation (treatment with the iron (II) chelator 2,2/'-dipyridyl), suggesting that these stresses are somehow related, giving good evidence that Fe2+ ion could have a role in the mechanism of oxygen sensing and/or response to hypoxia in B. emersonii. Furthermore, pretreatment of cells subjected to hypoxia with the antibiotic geldanamycin, a known inhibitor of the heat shock protein HSP90, caused a significant decrease in the induction of certain hypoxic genes, indicating that this fungus could have a mechanism similar to that of the mammalian hypoxia transcription factor...

Contribuição para o conhecimento de Chytridiomycota da Reserva Biológica de Paranapiacaba, Santo André, SP, Brasil / Contribution to the knowledge of the Chytridiomycota from the Reserva Biológica de Paranapiacaba, Santo André, State of São Paulo, Brazil

Estudo da diversidade de quitridiomicetos de solo e água, na "Reserva Biológica de Paranapiacaba", resultou no isolamento de 29 espécies, com três Blastocladiales, 23 Chytridiales, uma Monoblepharidales e duas Spizellomycetales. Dos táxons isolados, 69 por cento são citados pela primeira vez para a Reserva, 14 por cento para o estado de São Paulo, e 7 por cento para o país. É a primeira menção de Rhizophydium condylosum Karling no Brasil.

The diversity study of the chytrids from soil and water from the "Reserva Biológica de Paranapiacaba", yielded 29 species, with three Blastocladiales, 23 Chytridiales, one Monoblepharidales and two Spizellomycetales. From these, 69 percent taxa were cited for the first time for Reserve, 14 percent for São Paulo State and 7 percent for Brazil. Rhizophydium condylosum Karling is being mentioned for the first time in Brazil.

Síndrome de Asfixia Sumersión / Asphyxia Drowning Syndrome

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