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Sample records for paracoccidioides brasiliensis yeast

  1. Comparison of various techniques for determining viability of Paracoccidioides brasiliensis yeast-form cells.

    PubMed Central

    Restrepo, A; Cano, L E; de Bedout, C; Brummer, E; Stevens, D A

    1982-01-01

    The viability of Paracoccidioides brasiliensis yeast-form cells was determined by colony-forming units, direct fluorescent staining, and production of germ tubes in slide culture. The first procedure was unreliable and time consuming; the latter two showed better correlation with hemacytometer total cell counts and required significantly less time. PMID:7107858

  2. Biochemical differentiation of mycelium and yeast forms of Paracoccidioides brasiliensis by Fourier transform infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Castilho, Maiara L.; Campos, Claudia B. L.; Matos, Tatiana G. F.; de Abreu, Geraldo M. A.; Martin, Airton A.; Raniero, Leandro

    2012-01-01

    Paracoccidioides brasiliensis the etiological agent of paracoccidioidomycosis, is a dimorphic fungus existing as mycelia in the environment (or at 25 °C in vitro) and as yeast cells in the human host (or at 37°C in vitro). The most prominent difference between both forms is probably the cell wall polysaccharide, being 1,3-?-glucan usually found in mycelia and 1,3-?-glucan found in yeasts, but a plethora of other differences have already been described. In this work, we performed a Fourier Transform Infrared Spectroscopy analysis to compare the yeast and mycelia forms of P. brasiliensis and found additional biochemical differences. The analysis of the spectra showed that differences were distributed in chemical bonds of proteins, lipids and carbohydrates.

  3. Estradiol-binding proteins from mycelial and yeast-form cultures of Paracoccidioides brasiliensis.

    PubMed Central

    Stover, E P; Schär, G; Clemons, K V; Stevens, D A; Feldman, D

    1986-01-01

    Paracoccidioides brasiliensis, the etiologic agent of paracoccidioidomycosis, causes disease much more frequently in men than it does in women, suggesting that the hormonal milieu of the host might influence P. brasiliensis pathogenicity. We recently demonstrated that cytosol from yeast cultures of P. brasiliensis contains a high-affinity, low-capacity, tritiated 17 beta-estradiol [( 3H]estradiol)-binding protein. Estradiol and, to a lesser degree, diethylstilbestrol (DES), inhibited the transformation of P. brasiliensis cultures from the mycelial to the yeast form, an event critical to the establishment of infection. Our current studies demonstrated a somewhat higher affinity (apparent dissociation constant [Kd], approximately equal to 6 to 12 nM) of the estrogen-binding protein for [3H]estradiol than was previously described for yeast cytosol. The presence of both high- and low-affinity estrogen-binding sites in yeast-form P. brasiliensis cytosol was detected after warming the cytosol to 37 degrees C. The high-affinity protein was labile to further heating (56 degrees C), although the low-affinity protein was stable. Additional experiments demonstrated the presence of an estrogen-binding protein in cytosol prepared from mycelial-form P. brasiliensis. This estrogen-binding protein had a slightly lower affinity for [3H]estradiol (Kd approximately equal to 13 nM), and its cytosol contained somewhat fewer binding sites (approximately equal to 78 fmol/mg of protein) than did yeast-form P. brasiliensis cytosol. Of particular interest was the finding that DES, a weak competitor for [3H]estradiol binding in yeast cytosol, displaced [3H]estradiol from the mycelial-form binding moiety. DES had a 50- to 100-fold-lower affinity for the [3H]estradiol-binding protein than did estradiol, consistent with its lower bioactivity in the mycelial-to-yeast-form transformation studies. The current results lend further support to our hypothesis that endogenous estrogens in the host, acting through the cytosol binding protein in the fungus, inhibit mycelial-to-yeast-form transformation, thus explaining the resistance of women to paracoccidioidomycosis. PMID:3079729

  4. Inhibition by estrogens of conidium-to-yeast conversion in the fungus Paracoccidioides brasiliensis.

    PubMed Central

    Salazar, M E; Restrepo, A; Stevens, D A

    1988-01-01

    Conidia produced by Paracoccidioides brasiliensis are inhibited by mammalian estrogens in their in vitro conversion into yeast-form cells. This was demonstrated with four different isolates. In these experiments, conversion was reduced to 10.7 and 34.4% of the control values by 17-beta-estradiol at 10(-6) and 10(-8) M, respectively. At the same concentrations, the synthetic estrogen diethylstilbestrol was slightly less inhibitory. In contrast, other sex hormones and analogs, i.e., testosterone, 17-alpha-estradiol, tamoxifen, and hydroxytamoxifen, had no effect on conidium-to-yeast conversion. Previous studies have shown that estrogens similarly inhibit mycelium-to-yeast-form transition in P. brasiliensis. Conidia, and not mycelial fragments, are believed to be the natural infectious propagules. These findings with conidia support the hypothesis that estrogens, affecting the initial host-parasite interactions by suppressing conversion to the parasitic form of the organism, are, at least in part, responsible for the greater resistance of females to paracoccidioidomycosis. Images PMID:3343055

  5. Estrogens inhibit mycelium-to-yeast transformation in the fungus Paracoccidioides brasiliensis: implications for resistance of females to paracoccidioidomycosis.

    PubMed Central

    Restrepo, A; Salazar, M E; Cano, L E; Stover, E P; Feldman, D; Stevens, D A

    1984-01-01

    Evidence that disease due to the thermally dimorphic fungus Paracoccidioides brasiliensis occurs post-puberty predominantly in males led us to hypothesize that hormonal factors critically affect its pathogenesis. We show here that estrogens inhibit mycelial- to yeast-form transformation of P. brasiliensis in vitro. Transformation of three isolates was inhibited to 71, 33, and 19% of the control values in the presence of 10(-10), 10(-8), and 10(-6) M 17 beta-estradiol, respectively. The synthetic estrogen diethylstilbestrol was active but less potent than estradiol, whereas testosterone, 17 alpha-estradiol, tamoxifen, and corticosterone were inactive. This function was specifically inhibited, since yeast-to-mycelium transformation, yeast growth, and yeast reproduction by budding were unaffected by 17 beta-estradiol. Of note is the fact that mycelium-to-yeast transformation occurs as the first step in vivo in the establishment of infection. The cytosol of the three isolates studied possesses a steroid-binding protein which has high affinity for 17 beta-estradiol. We believe that this binding protein represents a P. brasiliensis hormone receptor which can also recognize mammalian estrogens. We hypothesize that the ability of estrogen to decrease or delay mycelium-to-yeast transformation at the initial site of infection contributes to or is responsible for the marked resistance of females, and that the binder described is the molecular site of action. Images PMID:6500694

  6. Macrophage Interaction with Paracoccidioides brasiliensis Yeast Cells Modulates Fungal Metabolism and Generates a Response to Oxidative Stress

    PubMed Central

    Parente-Rocha, Juliana Alves; Parente, Ana Flávia Alves; Baeza, Lilian Cristiane; Bonfim, Sheyla Maria Rondon Caixeta; Hernandez, Orville; McEwen, Juan G.; Bailão, Alexandre Melo; Taborda, Carlos Pelleschi; Borges, Clayton Luiz; Soares, Célia Maria de Almeida

    2015-01-01

    Macrophages are key players during Paracoccidioides brasiliensis infection. However, the relative contribution of the fungal response to counteracting macrophage activity remains poorly understood. In this work, we evaluated the P. brasiliensis proteomic response to macrophage internalization. A total of 308 differentially expressed proteins were detected in P. brasiliensis during infection. The positively regulated proteins included those involved in alternative carbon metabolism, such as enzymes involved in gluconeogenesis, beta-oxidation of fatty acids and amino acids catabolism. The down-regulated proteins during P. brasiliensis internalization in macrophages included those related to glycolysis and protein synthesis. Proteins involved in the oxidative stress response in P. brasiliensis yeast cells were also up-regulated during macrophage infection, including superoxide dismutases (SOD), thioredoxins (THX) and cytochrome c peroxidase (CCP). Antisense knockdown mutants evaluated the importance of CCP during macrophage infection. The results suggested that CCP is involved in a complex system of protection against oxidative stress and that gene silencing of this component of the antioxidant system diminished the survival of P. brasiliensis in macrophages and in a murine model of infection. PMID:26360774

  7. Paracoccidioides brasiliensis Enolase Is a Surface Protein That Binds Plasminogen and Mediates Interaction of Yeast Forms with Host Cells ?

    PubMed Central

    Nogueira, Sarah Veloso; Fonseca, Fernanda L.; Rodrigues, Marcio L.; Mundodi, Vasanth; Abi-Chacra, Erika A.; Winters, Michael S.; Alderete, John F.; Soares, Célia Maria de Almeida

    2010-01-01

    Paracoccidioidomycosis (PCM), caused by the dimorphic fungus Paracoccidioides brasiliensis, is a disseminated, systemic disorder that involves the lungs and other organs. The ability of the pathogen to interact with host components, including extracellular matrix (ECM) proteins, is essential to further colonization, invasion, and growth. Previously, enolase (EC 4.2.1.11) was characterized as a fibronectin binding protein in P. brasiliensis. Interaction of surface-bound enolase with plasminogen has been incriminated in tissue invasion for pathogenesis in several pathogens. In this paper, enolase was expressed in Escherichia coli as a recombinant glutathione S-transferase (GST) fusion protein (recombinant P. brasiliensis enolase [rPbEno]). The P. brasiliensis native enolase (PbEno) was detected at the fungus surface and cytoplasm by immunofluorescence with an anti-rPbEno antibody. Immobilized purified rPbEno bound plasminogen in a specific, concentration-dependent fashion. Both native enolase and rPbEno activated conversion of plasminogen to plasmin through tissue plasminogen activator. The association between PbEno and plasminogen was lysine dependent. In competition experiments, purified rPbEno, in its soluble form, inhibited plasminogen binding to fixed P. brasiliensis, suggesting that this interaction required surface-localized PbEno. Plasminogen-coated P. brasiliensis yeast cells were capable of degrading purified fibronectin, providing in vitro evidence for the generation of active plasmin on the fungus surface. Exposure of epithelial cells and phagocytes to enolase was associated with an increased expression of surface sites of adhesion. In fact, the association of P. brasiliensis with epithelial cells and phagocytes was increased in the presence of rPbEno. The expression of PbEno was upregulated in yeast cells derived from mouse-infected tissues. These data indicate that surface-associated PbEno may contribute to the pathogenesis of P. brasiliensis. PMID:20605975

  8. Differential PbP27 expression in the yeast and mycelial forms of the Paracoccidioides brasiliensis species complex.

    PubMed

    García Blanco, S; Muñoz, J F; Torres, I; Díez Posada, S; Gómez, B L; McEwen, J G; Restrepo, S; García, A M

    2011-12-01

    p27 is an antigenic protein produced by Paracoccidioides brasiliensis, the etiologic agent of paracoccidioidomycosis (PCM). Despite its unknown function, it has been suggested as a putative virulence factor, proposed as a suitable target for the design of diagnostic tools and vaccines, and considered as an enhancer in antifungal treatment of PCM. We evaluated sequence polymorphisms of PbP27 gene sequence among isolates, finding some polymorphisms associated with the isolates' phylogenetic origin. In order to determine if there was a differential expression pattern between morphological states and among isolates, we also evaluated PbP27 expression, at transcriptional and translational levels, in mycelia and yeast cultures in 14 isolates belonging to the P. brasiliensis species complex (S1, PS2, PS3, and "Pb01-like", proposed to be named Paracoccidioides lutzii) by two techniques, real time RT-PCR (RT-qPCR) and protein dot blot. For the latter, four protein extracts from different cell localizations (SDS or ?-mercaptoethanol, cytoplasmic and extracellular proteins) were analyzed for each isolate. p27 was present in the four extracts evaluated, mainly in the SDS extract, corresponding to an extract containing proteins loosely attached to the cell wall. This information correlates with immunohistochemical analysis, where positive staining of the yeasts' cell wall was observed. We found that p27 was present in all isolates, mainly in the yeast form. This pattern was corroborated by RT-qPCR results, with higher expression levels found in the yeast form for most of the isolates. The results provide new insights into the expression patterns of this protein, and further characterize it in view of potential uses as a diagnostic and/or therapeutic tool. PMID:21945996

  9. Involvement of an Alternative Oxidase in Oxidative Stress and Mycelium-to-Yeast Differentiation in Paracoccidioides brasiliensis ? †

    PubMed Central

    Martins, Vicente P.; Dinamarco, Taisa M.; Soriani, Frederico M.; Tudella, Valéria G.; Oliveira, Sergio C.; Goldman, Gustavo H.; Curti, Carlos; Uyemura, Sérgio A.

    2011-01-01

    Paracoccidioides brasiliensis is a thermodimorphic human pathogenic fungus that causes paracoccidioidomycosis (PCM), which is the most prevalent systemic mycosis in Latin America. Differentiation from the mycelial to the yeast form (M-to-Y) is an essential step for the establishment of PCM. We evaluated the involvement of mitochondria and intracellular oxidative stress in M-to-Y differentiation. M-to-Y transition was delayed by the inhibition of mitochondrial complexes III and IV or alternative oxidase (AOX) and was blocked by the association of AOX with complex III or IV inhibitors. The expression of P. brasiliensis aox (Pbaox) was developmentally regulated through M-to-Y differentiation, wherein the highest levels were achieved in the first 24 h and during the yeast exponential growth phase; Pbaox was upregulated by oxidative stress. Pbaox was cloned, and its heterologous expression conferred cyanide-resistant respiration in Saccharomyces cerevisiae and Escherichia coli and reduced oxidative stress in S. cerevisiae cells. These results reinforce the role of PbAOX in intracellular redox balancing and demonstrate its involvement, as well as that of other components of the mitochondrial respiratory chain complexes, in the early stages of the M-to-Y differentiation of P. brasiliensis. PMID:21183691

  10. Morphological Transition of Paracoccidioides brasiliensis Conidia to Yeast Cells: In Vivo Inhibition in Females

    PubMed Central

    Aristizabal, Beatriz H.; Clemons, Karl V.; Stevens, David A.; Restrepo, Angela

    1998-01-01

    Clinical paracoccidioidomycosis is 13 times more common in men than in women. Estrogen inhibits the transition of mycelia or conidia (the saprophytic form of Paracoccidoides brasiliensis) to yeasts (the parasitic form) in vitro. Here, we show that, in male mice that were infected intranasally (mimicking natural infection) the transition of conidia in bronchoalveolar lavage fluids to intermediate forms and yeasts occurred over 24 to 96 h; CFU and yeasts (shown by histopathology) increased subsequently. In females, transition did not occur and infection cleared. These events in vivo are consistent with epidemiological and in vitro observations, suggesting that female hormones block transition and are responsible for resistance. PMID:9784579

  11. NLRP3 Inflammasome Activation by Paracoccidioides brasiliensis

    PubMed Central

    Almeida, Raquel Das Neves; Correa, Rafael; Burgel, Pedro Henrique; Bocca, Anamélia Lorenzetti

    2013-01-01

    Paracoccidioides brasiliensis is the etiologic agent of paracoccidioidomycosis (PCM), the most prevalent systemic mycosis that is geographically confined to Latin America. The pro-inflammatory cytokine IL-1β that is mainly derived from the activation of the cytoplasmic multiprotein complex inflammasome is an essential host factor against opportunistic fungal infections; however, its role in infection with a primary fungal pathogen, such as P. brasiliensis, is not well understood. In this study, we found that murine bone marrow-derived dendritic cells responded to P. brasiliensis yeast cells infection by releasing IL-1β in a spleen tyrosine kinase (Syk), caspase-1 and NOD-like receptor (NLR) family member NLRP3 dependent manner. In addition, P. brasiliensis-induced NLRP3 inflammasome activation was dependent on potassium (K+) efflux, reactive oxygen species production, phagolysosomal acidification and cathepsin B release. Finally, using mice lacking the IL-1 receptor, we demonstrated that IL-1β signaling has an important role in killing P. brasiliensis by murine macrophages. Altogether, our results demonstrate that the NLRP3 inflammasome senses and responds to P. brasiliensis yeast cells infection and plays an important role in host defense against this fungus. PMID:24340123

  12. Distinct patterns of yeast cell morphology and host responses induced by representative strains of Paracoccidioides brasiliensis (Pb18) and Paracoccidioides lutzii (Pb01).

    PubMed

    Siqueira, Isaque Medeiros; Fraga, Cecília Lívia Falcomer; Amaral, André Correa; Souza, Ana Camila Oliveira; Jerônimo, Márcio Souza; Correa, José Raimundo; Magalhães, Kelly Grace; Inácio, Carlos Antônio; Ribeiro, Alice Melo; Burguel, Pedro Henrique; Felipe, Maria Sueli; Tavares, Aldo Henrique; Bocca, Anamelia Lorenzetti

    2016-02-01

    Paracoccidioidomycosis (PCM) is a systemic mycosis, widespread in Latin America. PCM is a granulomatous disease characterized by a polymorphism of lesions depending on the pathogen's virulence, the immune status of the host and its genetic susceptibility. The thermodimorphic fungus Paracoccidioides brasiliensis was considered the only etiologic agent of PCM, yet recent works have shown significant genetic diversity among different strains of P. brasiliensis. Therefore, it has been proposed for a new species within the Paracoccidioides genus, named Paracoccidioides lutzii. To better understand the fungus-host interactions elicited by strains Pb01 and Pb18 as key representatives of P. lutzii and P. brasiliensis, respectively, we carried out studies to investigate differences in morphology, induced immune response, virulence and pathology between these two Paracoccidioides species. Our results demonstrate distinct patterns of host-parasite interaction and pathology caused by Pb18 and Pb01. These results open up new fronts for NEW: clinical studies, which may result in significant consequences for the diagnosis and treatment of PCM. Considering that our results cannot be extended to all strains of both species, more studies about the virulence among Paracoccioides must be explored in the future. PMID:26384386

  13. Expressed Sequence Tag Analysis of the Human Pathogen Paracoccidioides brasiliensis Yeast Phase: Identification of Putative Homologues of Candida albicans Virulence and Pathogenicity Genes

    PubMed Central

    Goldman, Gustavo H.; dos Reis Marques, Everaldo; Custódio Duarte Ribeiro, Diógenes; Ângelo de Souza Bernardes, Luciano; Quiapin, Andréa Carla; Vitorelli, Patrícia Marostica; Savoldi, Marcela; Semighini, Camile P.; de Oliveira, Regina C.; Nunes, Luiz R.; Travassos, Luiz R.; Puccia, Rosana; Batista, Wagner L.; Ferreira, Leslie Ecker; Moreira, Júlio C.; Bogossian, Ana Paula; Tekaia, Fredj; Nobrega, Marina Pasetto; Nobrega, Francisco G.; Goldman, Maria Helena S.

    2003-01-01

    Paracoccidioides brasiliensis, a thermodimorphic fungus, is the causative agent of the prevalent systemic mycosis in Latin America, paracoccidioidomycosis. We present here a survey of expressed genes in the yeast pathogenic phase of P. brasiliensis. We obtained 13,490 expressed sequence tags from both 5? and 3? ends. Clustering analysis yielded the partial sequences of 4,692 expressed genes that were functionally classified by similarity to known genes. We have identified several Candida albicans virulence and pathogenicity homologues in P. brasiliensis. Furthermore, we have analyzed the expression of some of these genes during the dimorphic yeast-mycelium-yeast transition by real-time quantitative reverse transcription-PCR. Clustering analysis of the mycelium-yeast transition revealed three groups: (i) RBT, hydrophobin, and isocitrate lyase; (ii) malate dehydrogenase, contigs Pb1067 and Pb1145, GPI, and alternative oxidase; and (iii) ubiquitin, delta-9-desaturase, HSP70, HSP82, and HSP104. The first two groups displayed high mRNA expression in the mycelial phase, whereas the third group showed higher mRNA expression in the yeast phase. Our results suggest the possible conservation of pathogenicity and virulence mechanisms among fungi, expand considerably gene identification in P. brasiliensis, and provide a broader basis for further progress in understanding its biological peculiarities. PMID:12582121

  14. Cell organisation, sulphur metabolism and ion transport-related genes are differentially expressed in Paracoccidioides brasiliensis mycelium and yeast cells

    PubMed Central

    Andrade, Rosângela V; Paes, Hugo C; Nicola, André M; de Carvalho, Maria José A; Fachin, Ana Lúcia; Cardoso, Renato S; Silva, Simoneide S; Fernandes, Larissa; Silva, Silvana P; Donadi, Eduardo A; Sakamoto-Hojo, Elza T; Passos, Geraldo AS; Soares, Célia MA; Brígido, Marcelo M; Felipe, Maria Sueli S

    2006-01-01

    Background Mycelium-to-yeast transition in the human host is essential for pathogenicity by the fungus Paracoccidioides brasiliensis and both cell types are therefore critical to the establishment of paracoccidioidomycosis (PCM), a systemic mycosis endemic to Latin America. The infected population is of about 10 million individuals, 2% of whom will eventually develop the disease. Previously, transcriptome analysis of mycelium and yeast cells resulted in the assembly of 6,022 sequence groups. Gene expression analysis, using both in silico EST subtraction and cDNA microarray, revealed genes that were differential to yeast or mycelium, and we discussed those involved in sugar metabolism. To advance our understanding of molecular mechanisms of dimorphic transition, we performed an extended analysis of gene expression profiles using the methods mentioned above. Results In this work, continuous data mining revealed 66 new differentially expressed sequences that were MIPS(Munich Information Center for Protein Sequences)-categorised according to the cellular process in which they are presumably involved. Two well represented classes were chosen for further analysis: (i) control of cell organisation – cell wall, membrane and cytoskeleton, whose representatives were hex (encoding for a hexagonal peroxisome protein), bgl (encoding for a 1,3-β-glucosidase) in mycelium cells; and ags (an α-1,3-glucan synthase), cda (a chitin deacetylase) and vrp (a verprolin) in yeast cells; (ii) ion metabolism and transport – two genes putatively implicated in ion transport were confirmed to be highly expressed in mycelium cells – isc and ktp, respectively an iron-sulphur cluster-like protein and a cation transporter; and a putative P-type cation pump (pct) in yeast. Also, several enzymes from the cysteine de novo biosynthesis pathway were shown to be up regulated in the yeast form, including ATP sulphurylase, APS kinase and also PAPS reductase. Conclusion Taken together, these data show that several genes involved in cell organisation and ion metabolism/transport are expressed differentially along dimorphic transition. Hyper expression in yeast of the enzymes of sulphur metabolism reinforced that this metabolic pathway could be important for this process. Understanding these changes by functional analysis of such genes may lead to a better understanding of the infective process, thus providing new targets and strategies to control PCM. PMID:16907987

  15. Ultrastructure of Dimorphic Transformation in Paracoccidioides brasiliensis

    PubMed Central

    Carbonell, Luis M.

    1969-01-01

    The fine structure of Paracoccidioides brasiliensis undergoing temperature-dependent transformation from mycelium to yeast and vice versa (M ? Y) was studied. The transitional form to mycelium from the yeast appears as an elongated bud that extends from the yeast and which has a mixture of characteristics from both the yeast and the mycelium. The transitional form to yeast from the mycelium starts with enlargement of the interseptal spaces and cracking of the outer electron-dense layer of the cell wall of the hypha. Later the interseptal spaces tend to become round and separate. In M ? Y only few interseptal spaces seem to transform. The yeast is produced by self-transformation of the hypha. In Y ? M a new structure is formed and the yeast dies. Intrahyphal hyphae are observed during the transformation from M ? Y, and intrayeast hyphae during the Y ? M. Due to the high mortality and breakage observed in both types of transformations, we believe that wound of the yeast or the mycelium could elicit this phenomenon. Images PMID:5359610

  16. Paracoccidioides brasiliensis AND Paracoccidioides lutzii, A SECRET LOVE AFFAIR

    PubMed Central

    ARANTES, Thales Domingos; BAGAGLI, Eduardo; NIÑO-VEGA, Gustavo; SAN-BLAS, Gioconda; THEODORO, Raquel Cordeiro

    2015-01-01

    SUMMARY To commemorate Prof. Carlos da Silva Lacaz's centennial anniversary, the authors have written a brief account of a few, out of hundreds, biological, ecological, molecular and phylogenetic studies that led to the arrival of Paracoccidioides lutzii, hidden for more than a century within Paracoccidioides brasiliensis. Lacaz's permanent interest in this fungus, and particularly his conviction on the benefits that research on paracoccidioidomycosis would bring to patients, were pivotal in the development of the field. PMID:26465366

  17. Primers for Clinical Detection of Paracoccidioides brasiliensis

    PubMed Central

    San-Blas, Gioconda; Niño-Vega, Gustavo; Barreto, Laura; Hebeler-Barbosa, Flavia; Bagagli, Eduardo; Olivero de Briceño, Rosa; Mendes, Rinaldo Poncio

    2005-01-01

    From a 0.72-kb fragment universally generated in Paracoccidioides brasiliensis strains, primers were designed and tested on genomic DNA of this and other pathogenic fungi. They were specific and highly sensitive for P. brasiliensis DNA. Positive results were obtained when these were tested in clinical samples. PMID:16081993

  18. Human cord blood T-cell receptor alpha beta cell responses to protein antigens of Paracoccidioides brasiliensis yeast forms.

    PubMed Central

    Munk, M E; Kaufmann, S H

    1995-01-01

    Paracoccidioides brasiliensis causes a chronic granulomatous mycosis, prevalent in South America, and cell-mediated immunity represents the principal mode of protection against this fungal infection. We investigated the response of naive cord blood T cells to P. brasiliensis lysates. Our results show: (1) P. brasiliensis stimulates T-cell expansion, interleukin-2 (IL-2) production and differentiation into cytotoxic T cells; (2) T-cell stimulation depends on P. brasiliensis processing and major histocompatibility complex (MHC) class II expression; (3) the responsive T-cell population expresses alpha beta T-cell receptors (TCR) with different V beta gene products, CD4 and CD45RO; (4) the P. brasiliensis components involved in T-cell expansion primarily reside in a high molecular weight (100,000 MW) and a low molecular weight (< 1000 MW) protein fraction. These results indicate that protein antigens of P. brasiliensis stimulate cord blood CD4 alpha beta T cells, independent from in vivo presensitization, and thus question direct correlation of positive in vitro responses with protective immunity in vivo. PMID:7890308

  19. Paracoccidioides brasiliensis Infection in Small Wild Mammals.

    PubMed

    Sbeghen, Mônica Raquel; Zanata, Thais Bastos; Macagnan, Rafaela; de Abreu, Kaue Cachuba; da Cunha, Willian Luiz; Watanabe, Maria Angelica Ehara; de Camargo, Zoilo Pires; Ono, Mario Augusto

    2015-12-01

    Paracoccidioidomycosis (PCM) is a systemic mycosis prevalent in Brazil and other Latin American countries. The etiological agents of PCM are the thermo-dimorphic fungi Paracoccidioides brasiliensis and P. lutzii. Taking into account that the natural habitat of Paracoccidioides spp. is still undefined, domestic and wild animals could be useful as indicators of Paracoccidioides spp. presence in endemic areas. The objective of this study was to evaluate the infection of small wild mammals by P. brasiliensis in an endemic area for human PCM. Samples from 38 wild mammals from different species such as Akodon sp., Thaptomys nigrita, Euryoryzomys russatus, Oligoryzomys nigripes, Monodelphis sp., Sooretamys angouya, Abrawayaomys angouya, Abrawayaomys ruschii and Akodontinae sp. were evaluated by ELISA, immunodiffusion, histopathology, nested PCR and culture. The overall positivity to gp43 observed in the ELISA was 23.7%. Samples from heart and liver of one O. nigripes were PCR positive, and the animal was also seropositive to gp43 in ELISA. This study showed that wild animals living in endemic areas for PCM are infected with P. brasiliensis and can be valuable epidemiological markers of the fungus presence in the environment. This is the first evidence of PCM infection in Akodon sp., E. russatus, T. nigrita and O. nigripes. PMID:26232125

  20. Identification of Paracoccidioides brasiliensis by gold nanoprobes

    NASA Astrophysics Data System (ADS)

    Martins, Jaciara F. S.; Castilho, Maiara L.; Cardoso, Maria A. G.; Carreiro, Andrea P.; Martin, Airton A.; Raniero, Leandro

    2012-01-01

    Paracoccidioides brasiliensis (P. brasiliensis) is a thermal dimorphic fungus and causal agent of paracoccidioidomycosis. Epidemiological data shows that it is mainly concentrated in Central and South America countries, with most registered cases in Colombia, Brazil, and Venezuela. The histopathological similarity with others fungal infection makes the diagnosis of P. brasiliensis more complicated. Therefore, the aim of this work was to find a positive and negative test for P. brasiliensis using gold nanoprobes as a new tool for P. brasiliensis detection. Gold nanoparticles were synthesized by reduction of gold chloride with sodium citrate. The results of this procedure is a wine-red solution with a maximum absorption in the range of ~520-530nm. A specific P. brasiliensis sequence of oligonucleotide was bonded to the nanoparticles, which maintained the wine-red color. The color changes from red to blue for negative diagnostic and is unchanged for a positive test. The H-bond interaction of DNA with the complementary DNA keeps strands together and forms double helical structure, maintaining the colloid stability. However, for non-complimentary DNA sequence the nanoprobes merge into a cluster, changing the light absorption.

  1. In vitro susceptibility testing of Paracoccidioides brasiliensis to sulfonamides.

    PubMed Central

    Restrepo, A; Arango, M D

    1980-01-01

    A total of 60 clinical isolates of Paracoccidioides brasiliensis were tested for susceptibility to sulfadiazine and sulfadimethoxyne by the agar dilution technique. A modification of the Mueller-Hinton medium was devised which gave good growth of the yeast form. The minimum inhibitory concentrations for only 51.6% of the isolates were in the range of the recommended blood serum concentration (50 micrograms/ml). For 6 to 8% of the isolates, the minimum inhibitory concentrations were above 200 micrograms of both sulfadiazine and sulfadimethoxyne per ml. A significant decreases in susceptibility was demonstrated for one isolate obtained from a patient relapsing during sulfonamide therapy. Images PMID:7416744

  2. Alternative Oxidase Mediates Pathogen Resistance in Paracoccidioides brasiliensis Infection

    PubMed Central

    Hernández Ruiz, Orville; Gonzalez, Angel; Almeida, Agostinho J.; Tamayo, Diana; Garcia, Ana Maria; Restrepo, Angela; McEwen, Juan G.

    2011-01-01

    Background Paracoccidioides brasiliensis is a human thermal dimorphic pathogenic fungus. Survival of P. brasiliensis inside the host depends on the adaptation of this fungal pathogen to different conditions, namely oxidative stress imposed by immune cells. Aims and Methodology In this study, we evaluated the role of alternative oxidase (AOX), an enzyme involved in the intracellular redox balancing, during host-P. brasiliensis interaction. We generated a mitotically stable P. brasiliensis AOX (PbAOX) antisense RNA (aRNA) strain with a 70% reduction in gene expression. We evaluated the relevance of PbAOX during interaction of conidia and yeast cells with IFN-? activated alveolar macrophages and in a mouse model of infection. Additionally, we determined the fungal cell's viability and PbAOX in the presence of H2O2. Results Interaction with IFN-? activated alveolar macrophages induced higher levels of PbAOX gene expression in PbWt conidia than PbWt yeast cells. PbAOX-aRNA conidia and yeast cells had decreased viability after interaction with macrophages. Moreover, in a mouse model of infection, we showed that absence of wild-type levels of PbAOX in P. brasiliensis results in a reduced fungal burden in lungs at weeks 8 and 24 post-challenge and an increased survival rate. In the presence of H2O2, we observed that PbWt yeast cells increased PbAOX expression and presented a higher viability in comparison with PbAOX-aRNA yeast cells. Conclusions These data further support the hypothesis that PbAOX is important in the fungal defense against oxidative stress imposed by immune cells and is relevant in the virulence of P. brasiliensis. PMID:22039556

  3. Paracoccidioides brasiliensis pancreatic destruction in Calomys callosus experimentally infected

    PubMed Central

    2009-01-01

    Background The wild rodent Calomys callosus is notably resistant to Trypanosoma cruzi infection. In order to better characterize this animal model for experimental infections, we inoculated C. callosus intraperitoneally with Paracoccidioides brasiliensis, a thermally dimorphic fungus that causes a chronic disease with severe granuloma formation in the mouse and humans. The dissemination of P. brasiliensis cells through the lungs, liver, pancreas, and spleen was assessed by histological analysis. Results The animals were susceptible to infection and showed a granulomatous reaction. C. callosus presented peritonitis characterized by the presence of exudates containing a large number of yeast cells. Extensive accumulation of yeast cells with intense destruction of the parenchyma was observed in the pancreas, which reduced the glucose levels of infected animals. These lesions were regressive in the liver, spleen, and lungs until complete recovery. The role of estrogen during C. callosus infection with P. brasiliensis was addressed by infecting ovariectomized animals. It was observed a reduced inflammatory response as well as reduced extension of tissue damage. Removal of ovaries reestablished the normal glucose levels during infection. Conclusion Taken together, the results presented here reveal the pancreas as being an important organ for the persistence of P. brasiliensis during infection of C. callosus and that estrogen plays an important role in the susceptibility of the animals to this pathogen. PMID:19422699

  4. Ultrastructure of phagocytosed Paracoccidioides brasiliensis in nonactivated or activated macrophages.

    PubMed Central

    Brummer, E; Sun, S H; Harrison, J L; Perlman, A M; Philpott, D E; Stevens, D A

    1990-01-01

    Transmission electron microscopy was used to study ultrastructures in Paracoccidioides brasiliensis yeast cells after ingestion by nonactivated or cytokine-activated murine peritoneal macrophages. Yeast cells ingested by nonactivated macrophages had typical bi- and trilayered cell walls, plasma membranes, mitochondria, nuclei, vacuoles, etc., which remained intact for 24 h of coculture. In contrast, yeast cells ingested by activated macrophages exhibited abnormal mitochondrial ultrastructures within 4 h of interaction. Subsequent events that occurred were the formation of several clear vacuoles per cell, disintegration of the cytoplasm, and development of empty cells with intact walls. These findings provide, for the first time, insights into stepwise damage to fungal cells by activated macrophages (of particular interest in this instance because of prior evidence that the damage is due to nonoxidative mechanisms) and give possible clues regarding fungicidal mechanisms. Images PMID:2370112

  5. Susceptibility and resistance of inbred mice to Paracoccidioides brasiliensis.

    PubMed Central

    Calich, V. L.; Singer-Vermes, L. M.; Siqueira, A. M.; Burger, E.

    1985-01-01

    Nine different inbred strains of mice inoculated intraperitoneally with yeast cells of Paracoccidioides brasiliensis showed significantly varying patterns of susceptibility. The A/SN strain was found to be the most resistant, while BIOD2/nSn, BIO.A and BIOD2/oSn the most susceptible strains. These susceptibility differences were not dependent on the size of challenge inocula and sex of animals. All strains studied showed a mean survival time proportional to the size of inocula used. Although almost all infected male mice presented a shorter survival time when compared with females, significant mortality differences between sexes were found only in two of the strains studied, namely BALB/c and BIOD2/nSn. The H-2 region did not influence the susceptibility pattern since the A/SN and BIO.A strains share the same H-2 haplotype and were respectively highly resistant and susceptible to P. brasiliensis. Furthermore, the presence of C5 and unresponsiveness to lipopolysaccharide had no influence on the mortality data observed. Specific antibodies were detected only in a small number of animals and titres were consistently low, appearing later in the resistant (A/SN) than in a susceptible strain (BIO.A). Omentum, spleen and liver were the most affected organs in both strains, but the susceptible mice had more granulomatous lesions and earlier dissemination of the fungus. PMID:4063162

  6. New method for estimating digestion of Paracoccidioides brasiliensis by phagocytic cells in vitro.

    PubMed Central

    Goihman-Yahr, M; Essenfeld-Yahr, E; Albornoz, M C; Yarzábal, L; de Gómez, M H; San Martín, B; Ocanto, A; Convit, J

    1979-01-01

    We describe a method by which phagocytosis and digestion of Paracoccidioides brasiliensis yeast cells by polymorphonuclear leukocytes or other phagocytic cells may be estimated. Suspensions of P. brasiliensis in its yeastlike phase were sonicated, counted, and incubated with known numbers of peripheral blood polymorphonuclear leukocytes. At given intervals, cytocentrifuge droplets were stained by a variation of Papanicolaou's method. Stained preparations were examined with phase-contrast optics. Digested organisms showed total or partial disappearance of protoplasm. Green-stained cell walls resisted digestion. The proportion of digested cells as a function of time was estimated. Images PMID:90683

  7. Intracellular multiplication of Paracoccidioides brasiliensis in macrophages: killing and restriction of multiplication by activated macrophages.

    PubMed Central

    Brummer, E; Hanson, L H; Restrepo, A; Stevens, D A

    1989-01-01

    The effect of coculturing yeast-form Paracoccidioides brasiliensis with murine cells was studied. Coculture of resident peritoneal or pulmonary macrophages with P. brasiliensis for 72 h dramatically enhanced fungal multiplication 19.3 +/- 2.4- and 4.7 +/- 0.8-fold, respectively, compared with cocultures with lymph node cells or complete tissue culture medium alone. Support of P. brasiliensis multiplication by resident peritoneal macrophages was macrophage dose dependent. Lysates of macrophages, supernatants from macrophage cultures, or McVeigh-Morton broth, like complete tissue culture medium, did not support multiplication of P. brasiliensis in 72-h cultures. Time course microscopic studies of cocultures in slide wells showed that macrophages ingested P. brasiliensis cells and that the ingested cells multiplied intracellularly. In sharp contrast to resident macrophages, lymphokine-activated peritoneal and pulmonary macrophages not only prevented multiplication but reduced inoculum CFU by 96 and 100%, respectively, in 72 h. Microscopic studies confirmed killing and digestion of P. brasiliensis ingested by activated macrophages in 48 h. These findings indicate that resident macrophages are permissive for intracellular multiplication of P. brasiliensis and that this could be a factor in pathogenicity. By contrast, activated macrophages are fungicidal for P. brasiliensis. Images PMID:2744848

  8. Cerebriform colonies of Paracoccidioides brasiliensis isolated from nine-banded armadillos (Dasypus novemcinctus) at room temperature.

    PubMed

    Tanaka, R; Sano, A; Franco, M; Bagagli, E; Montenegro, M R; Nishimura, K; Miyaji, M

    2001-01-01

    Twelve isolates of Paracoccidioides brasiliensis generated cerebriform colonies at room temperature on potato glucose agar slants (PDA). These isolates contained abundant chlamydospores and yeast-like cells and are a subset of the 65 isolates obtained from nine-banded armadillos (Dasypus novemcinctus). They grew as a yeast form with typical multiple buddings at 37 degrees C on brain heart infusion agar supplemented with 1% glucose. After replating on PDA and culturing at room temperature for 2 months, the mutants appeared as cottonous colonies, which indicated that the morphological characteristics were unstable. PMID:11398643

  9. THE POWER OF THE SMALL: THE EXAMPLE OF Paracoccidioides brasiliensis CONIDIA

    PubMed Central

    RESTREPO, Angela; CANO, Luz Elena; GONZALEZ, Ángel

    2015-01-01

    SUMMARY Research on Paracoccidioides brasiliensis has centered in the yeast cell probably because of the lack of distinctive features in the mycelium. In 1942 and for the first time, lateral conidia were noticed in the fungus' hyphae. Later on, Brazilian, Venezuelan and Argentinean researchers described "aleurias" when the fungus was grown in natural substrates. In 1970 authors became interested in the conidia and were able to obtain them in large numbers and treat them as individual units. Their shape and size were defined and the presence of all the elements of a competent eukaryotic cell were demonstrated. Conidia exhibited thermal dimorphism and, additionally, when given intranasally to BALB/c male mice, they converted into yeasts in the lungs and produce progressive pulmonary lesions with further dissemination to other organs. Studies on the phagocyte-conidia interaction were revealing and showed that these versatile structures allow a better understanding of the host- P. brasiliensis interactions. PMID:26465363

  10. Morphological heterogeneity of Paracoccidioides brasiliensis: relevance of the Rho-like GTPase PbCDC42.

    PubMed

    Menino, João F; Osório, Nuno S; Sturme, Mark H J; Barros, Diana; Gomes-Alves, Ana G; Almeida, Agostinho J; Ludovico, Paula; Costa, Patricio; Goldman, Gustavo H; Rodrigues, Fernando

    2012-10-01

    Paracoccidioides brasiliensis budding pattern and polymorphic growth were previously shown to be closely linked to the expression of PbCDC42 and to influence the pathogenesis of the fungus. In this work we conducted a detailed morphogenetic evaluation of the yeast-forms of 11 different clinical and environmental P. brasiliensis isolates comprising four phylogenetic lineages (S1, PS2, PS3 and Pb01-like), as well as a PbCDC42 knock-down strain. High variations in the shape and size of mother and bud cells of each isolate were observed but we did not find a characteristic morphologic profile for any of the phylogenetic groups. In all isolates studied, the bud size and shape were demonstrated to be highly dependent on the mother cell. Importantly, we found strong correlations between PbCDC42 expression and both the shape of mother and bud cells and the size of the buds in all isolates and the knock-down strain. Our results suggested that PbCDC42 expression can explain approximately 80% of mother and bud cell shape and 19% of bud cell size. This data support PbCDC42 expression level as being a relevant predictor of P. brasiliensis morphology. Altogether, these findings quantitatively describe the polymorphic nature of the P. brasiliensis yeast form and provide additional support for the key role of PbCDC42 expression on yeast cell morphology. PMID:22493946

  11. A Paracoccidioides brasiliensis glycan shares serologic and functional properties with cryptococcal glucuronoxylomannan

    PubMed Central

    Albuquerque, Priscila C.; Cordero, Radames J.B.; Fonseca, Fernanda L.; da Silva, Roberta Peres; Ramos, Caroline L.; Miranda, Kildare R.; Casadevall, Arturo; Puccia, Rosana; Nosanchuk, Joshua D.; Nimrichter, Leonardo; Guimaraes, Allan J.; Rodrigues, Marcio L.

    2015-01-01

    The cell wall of the yeast form of the dimorphic fungus Paracoccidioides brasiliensis is enriched with ?1,3-glucans. In Cryptococcus neoformans, ?1,3-glucans interact with glucuronoxylomannan (GXM), a hetero polysaccharide that is essential for fungal virulence. In this study, we investigated the occurrence of P. brasiliensis glycans sharing properties with cryptococcal GXM. Protein database searches in P. brasiliensis revealed the presence of sequences homologous to those coding for enzymes involved in the synthesis of GXM and capsular architecture in C. neoformans. In addition, monoclonal antibodies (mAbs) raised to cryptococcal GXM bound to P. brasiliensis cells. Using protocols that were previously established for extraction and analysis of C. neoformans GXM, we recovered a P. brasiliensis glycan fraction composed of mannose and galactose, in addition to small amounts of glucose, xylose and rhamnose. In comparison with the C. neoformans GXM, the P. brasiliensis glycan fraction components had smaller molecular dimensions. The P. brasiliensis components, nevertheless, reacted with different GXM-binding mAbs. Extracellular vesicle fractions of P. brasiliensis also reacted with a GXM-binding mAb, suggesting that the polysaccharide-like molecule is exported to the extracellular space in secretory vesicles. An acapsular mutant of C. neoformans incorporated molecules from the P. brasiliensis extract onto the cell wall, resulting in the formation of surface networks that resembled the cryptococcal capsule. Coating the C. neoformans acapsular mutant with the P. brasiliensis glycan fraction resulted in protection against phagocytosis by murine macrophages. These results suggest that P. brasiliensis and C. neoformans share metabolic pathways required for the synthesis of similar polysaccharides and that P. brasiliensis yeast cell walls have molecules that mimic certain aspects of C. neoformans GXM. These findings are important because they provide additional evidence for the sharing of antigenically similar components across phylogenetically distant fungal species. Since GXM has been shown to be important for the pathogenesis of C. neoformans and to elicit protective antibodies, the finding of similar molecules in P. brasiliensis raises the possibility that these glycans play similar functions in paracoccidiomycosis. PMID:23010152

  12. Synergistic interaction of trimethoprim and sulfamethoxazole on Paracoccidioides brasiliensis.

    PubMed Central

    Stevens, D A; Vo, P T

    1982-01-01

    The in vitro interaction of trimethoprim and sulfamethoxazole on clinical isolates of Paracoccidioides brasiliensis was studied. With complete inhibition and a visual endpoint used as the criteria, three of four strains had minimal inhibitory concentrations that indicated resistance to sulfamethoxazole, and all four strains were resistant to trimethoprim. A marked synergism in inhibition was noted with the combination of these drugs against sulfa-resistant strains. A sulfamethoxazole/trimethoprim ratio of 5:1 was the most synergistic. Fifty percent inhibition, determined spectrophotometrically, of the strains could be achieved with sulfamethoxazole alone. In summary, the striking synergy observed suggests that combination chemotherapy with these drugs deserves further study. PMID:7103462

  13. TLR9 Activation Dampens the Early Inflammatory Response to Paracoccidioides brasiliensis, Impacting Host Survival

    PubMed Central

    Menino, João Filipe; Saraiva, Margarida; Gomes-Alves, Ana G.; Lobo-Silva, Diogo; Sturme, Mark; Gomes-Rezende, Jéssica; Saraiva, Ana Laura; Goldman, Gustavo H.; Cunha, Cristina; Carvalho, Agostinho; Romani, Luigina; Pedrosa, Jorge; Castro, António Gil; Rodrigues, Fernando

    2013-01-01

    Background Paracoccidioides brasiliensis causes paracoccidioidomycosis, one of the most prevalent systemic mycosis in Latin America. Thus, understanding the characteristics of the protective immune response to P. brasiliensis is of interest, as it may reveal targets for disease control. The initiation of the immune response relies on the activation of pattern recognition receptors, among which are TLRs. Both TLR2 and TLR4 have been implicated in the recognition of P. brasiliensis and regulation of the immune response. However, the role of TLR9 during the infection by this fungus remains unclear. Methodology/Principal findings We used in vitro and in vivo models of infection by P. brasiliensis, comparing wild type and TLR9 deficient (?/?) mice, to assess the contribution of TLR9 on cytokine induction, phagocytosis and outcome of infection. We show that TLR9 recognizes either the yeast form or DNA from P. brasiliensis by stimulating the expression/production of pro-inflammatory cytokines by bone marrow derived macrophages, also increasing their phagocytic ability. We further show that TLR9 plays a protective role early after intravenous infection with P. brasiliensis, as infected TLR9?/? mice died at higher rate during the first 48 hours post infection than wild type mice. Moreover, TLR9?/? mice presented tissue damage and increased expression of several cytokines, such as TNF-? and IL-6. The increased pattern of cytokine expression was also observed during intraperitoneal infection of TLR9?/? mice, with enhanced recruitment of neutrophils. The phenotype of TLR9?/? hosts observed during the early stages of P. brasiliensis infection was reverted upon a transient, 48 hours post-infection, neutrophil depletion. Conclusions/Significance Our results suggest that TLR9 activation plays an early protective role against P. brasiliensis, by avoiding a deregulated type of inflammatory response associated to neutrophils that may lead to tissue damage. Thus modulation of TLR9 may be of interest to potentiate the host response against this pathogen. PMID:23936560

  14. Detection of Antibodies against Paracoccidioides brasiliensis Melanin in In Vitro and In Vivo Studies during Infection ?

    PubMed Central

    Urán, Martha E.; Nosanchuk, Joshua D.; Restrepo, Angela; Hamilton, Andrew J.; Gómez, Beatriz L.; Cano, Luz E.

    2011-01-01

    Several cell wall constituents, including melanins or melanin-like compounds, have been implicated in the pathogenesis of a wide variety of microbial diseases caused by diverse species of pathogenic bacteria, fungi, and helminthes. Among these microorganisms, the dimorphic fungal pathogen Paracoccidioides brasiliensis produces melanin in its conidial and yeast forms. In the present study, melanin particles from P. brasiliensis were injected into BALB/c mice in order to produce monoclonal antibodies (MAbs). We identified five immunoglobulin G1 (IgG1) ?-chain and four IgM melanin-binding MAbs. The five IgG1 ?-chain isotypes are the first melanin-binding IgG MAbs ever reported. The nine MAbs labeled P. brasiliensis conidia and yeast cells both in vitro and in pulmonary tissues. The MAbs cross-reacted with melanin-like purified particles from other fungi and also with commercial melanins, such as synthetic and Sepia officinalis melanin. Melanization during paracoccidioidomycosis (PCM) was also further supported by the detection of IgG antibodies reactive to melanin from P. brasiliensis conidia and yeast in sera and bronchoalveolar lavage fluids from P. brasiliensis-infected mice, as well as in sera from human patients with PCM. Serum specimens from patients with other mycoses were also tested for melanin-binding antibodies by enzyme-linked immunosorbent assay, and cross-reactivities were detected for melanin particles from different fungal sources. These results suggest that melanin from P. brasiliensis is an immunologically active fungal structure that activates a strong IgG humoral response in humans and mice. PMID:21813659

  15. Proteomic Analysis Reveals That Iron Availability Alters the Metabolic Status of the Pathogenic Fungus Paracoccidioides brasiliensis

    PubMed Central

    Parente, Ana F. A.; Bailão, Alexandre M.; Borges, Clayton L.; Parente, Juliana A.; Magalhães, Adriana D.; Ricart, Carlos A. O.; Soares, Célia M. A.

    2011-01-01

    Paracoccidioides brasiliensis is a thermodimorphic fungus and the causative agent of paracoccidioidomycosis (PCM). The ability of P. brasiliensis to uptake nutrients is fundamental for growth, but a reduction in the availability of iron and other nutrients is a host defense mechanism many pathogenic fungi must overcome. Thus, fungal mechanisms that scavenge iron from host may contribute to P. brasiliensis virulence. In order to better understand how P. brasiliensis adapts to iron starvation in the host we compared the two-dimensional (2D) gel protein profile of yeast cells during iron starvation to that of iron rich condition. Protein spots were selected for comparative analysis based on the protein staining intensity as determined by image analysis. A total of 1752 protein spots were selected for comparison, and a total of 274 out of the 1752 protein spots were determined to have changed significantly in abundance due to iron depletion. Ninety six of the 274 proteins were grouped into the following functional categories; energy, metabolism, cell rescue, virulence, cell cycle, protein synthesis, protein fate, transcription, cellular communication, and cell fate. A correlation between protein and transcript levels was also discovered using quantitative RT-PCR analysis from RNA obtained from P. brasiliensis under iron restricting conditions and from yeast cells isolated from infected mouse spleens. In addition, western blot analysis and enzyme activity assays validated the differential regulation of proteins identified by 2-D gel analysis. We observed an increase in glycolytic pathway protein regulation while tricarboxylic acid cycle, glyoxylate and methylcitrate cycles, and electron transport chain proteins decreased in abundance under iron limiting conditions. These data suggest a remodeling of P. brasiliensis metabolism by prioritizing iron independent pathways. PMID:21829521

  16. Genes potentially relevant in the parasitic phase of the fungal pathogen Paracoccidioides brasiliensis.

    PubMed

    Borges, Clayton Luiz; Bailão, Alexandre Melo; Báo, Sonia N; Pereira, Maristela; Parente, Juliana Alves; de Almeida Soares, Célia Maria

    2011-01-01

    Paracoccidioides brasiliensis, a fungal pathogen of humans, switches from a filamentous spore-forming mold in the soil to a pathogenic budding-yeast in the human host. Dimorphism is regulated mainly by the temperature of incubation. Representational difference analysis (RDA) was performed between yeast cells of isolate Pb01 and from isolate Pb4940, the last growing as mycelia at the host temperature. Transcripts exhibiting increased expression during development of the yeast parasitic phase comprised those involved mainly in response to stress, transcriptional regulation and nitrogen metabolism. In this way, the isolate Pb01 increased the expression of a variety of transcripts encoding cell rescue proteins such as the heat shock protein HSP30, alpha-trehalose-phosphate synthase and DDR48 stress protein, suggesting the relevance of the defense mechanism against oxidative/heat shock stress in the fungal yeast phase. Other differentially expressed genes between the two isolates included those coding for cell wall/membrane-related proteins, suggesting the relevance of the fungal surface and it's remodeling to the dimorphism. We provide a set of novel yeast preferentially expressed genes and demonstrate the effectiveness of RDA for studying P. brasiliensis dimorphism. PMID:20669049

  17. Characterization of Paracoccidioides brasiliensis by FT-IR spectroscopy and nanotechnology

    NASA Astrophysics Data System (ADS)

    Ferreira, Isabelle; Ferreira-Strixino, Juliana; Castilho, Maiara L.; Campos, Claudia B. L.; Tellez, Claudio; Raniero, Leandro

    2016-01-01

    Paracoccidioides brasiliensis, the etiological agent of paracoccidioidomycosis, is a dimorphic fungus existing as mycelia in the environment (or at 25 °C in vitro) and as yeast cells in the human host (or at 37 °C in vitro). Because mycological examination of lesions in patients frequently is unable to show the presence of the fungus and serological tests can misdiagnose the disease with other mycosis, the development of new approach's for molecular identification of P. brasiliensis spurges is needed. This study describes the use of a gold nanoprobe of a known gene sequence of P. brasiliensis as a molecular tool to identify P. brasiliensis by regular polymerase chain reaction (PCR) associated with a colorimetric methods. This approach is suitable for testing in remote areas because it does not require any further step than gene amplification, being safer and cheaper than electrophoresis methods. The proposed test showed a color change of the PCR reaction mixture from red to blue in negative samples, whereas the solution remains red in positive samples. We also performed a Fourier Transform Infrared (FT-IR) Spectroscopy analysis to characterize and compare the chemical composition between yeast and mycelia forms, which revealed biochemical differences between these two forms. The analysis of the spectra showed that differences were distributed in chemical bonds of proteins, lipids and carbohydrates. The most prominent difference between both forms was vibration modes related to 1,3-β-glucan usually found in mycelia and 1,3-α-glucan found in yeasts and also chitin forms. In this work, we introduce FT-IR as a new method suitable to reveal overall differences that biochemically distinguish each form of P. brasiliensis that could be additionally used to discriminate biochemical differences among a single form under distinct environmental conditions.

  18. Characterization of Paracoccidioides brasiliensis by FT-IR spectroscopy and nanotechnology.

    PubMed

    Ferreira, Isabelle; Ferreira-Strixino, Juliana; Castilho, Maiara L; Campos, Claudia B L; Tellez, Claudio; Raniero, Leandro

    2016-01-01

    Paracoccidioides brasiliensis, the etiological agent of paracoccidioidomycosis, is a dimorphic fungus existing as mycelia in the environment (or at 25°C in vitro) and as yeast cells in the human host (or at 37°C in vitro). Because mycological examination of lesions in patients frequently is unable to show the presence of the fungus and serological tests can misdiagnose the disease with other mycosis, the development of new approach's for molecular identification of P. brasiliensis spurges is needed. This study describes the use of a gold nanoprobe of a known gene sequence of P. brasiliensis as a molecular tool to identify P. brasiliensis by regular polymerase chain reaction (PCR) associated with a colorimetric methods. This approach is suitable for testing in remote areas because it does not require any further step than gene amplification, being safer and cheaper than electrophoresis methods. The proposed test showed a color change of the PCR reaction mixture from red to blue in negative samples, whereas the solution remains red in positive samples. We also performed a Fourier Transform Infrared (FT-IR) Spectroscopy analysis to characterize and compare the chemical composition between yeast and mycelia forms, which revealed biochemical differences between these two forms. The analysis of the spectra showed that differences were distributed in chemical bonds of proteins, lipids and carbohydrates. The most prominent difference between both forms was vibration modes related to 1,3-β-glucan usually found in mycelia and 1,3-α-glucan found in yeasts and also chitin forms. In this work, we introduce FT-IR as a new method suitable to reveal overall differences that biochemically distinguish each form of P. brasiliensis that could be additionally used to discriminate biochemical differences among a single form under distinct environmental conditions. PMID:26241825

  19. Antibodies Against Glycolipids Enhance Antifungal Activity of Macrophages and Reduce Fungal Burden After Infection with Paracoccidioides brasiliensis

    PubMed Central

    Bueno, Renata A.; Thomaz, Luciana; Muñoz, Julian E.; da Silva, Cássia J.; Nosanchuk, Joshua D.; Pinto, Márcia R.; Travassos, Luiz R.; Taborda, Carlos P.

    2016-01-01

    Paracoccidioidomycosis is a fungal disease endemic in Latin America. Polyclonal antibodies to acidic glycosphingolipids (GSLs) from Paracoccidioides brasiliensis opsonized yeast forms in vitro increasing phagocytosis and reduced the fungal burden of infected animals. Antibodies to GSL were active in both prophylactic and therapeutic protocols using a murine intratracheal infection model. Pathological examination of the lungs of animals treated with antibodies to GSL showed well-organized granulomas and minimally damaged parenchyma compared to the untreated control. Murine peritoneal macrophages activated by IFN-γ and incubated with antibodies against acidic GSLs more effectively phagocytosed and killed P. brasiliensis yeast cells as well as produced more nitric oxide compared to controls. The present work discloses a novel target of protective antibodies against P. brasiliensis adding to other well-studied mediators of the immune response to this fungus. PMID:26870028

  20. Microsatellite Analysis of Three Phylogenetic Species of Paracoccidioides brasiliensis†

    PubMed Central

    Matute, Daniel R.; Sepulveda, Victoria E.; Quesada, Lina M.; Goldman, Gustavo H.; Taylor, John W.; Restrepo, Angela; McEwen, Juan G.

    2006-01-01

    Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, an important human systemic mycosis in Latin America. Recently, the existence of three different phylogenetic species (S1, PS2, and PS3) of P. brasiliensis was demonstrated. Despite being genetically isolated, all three species were capable of inducing disease in both humans and animals, although lower virulence has been found with the PS2 species. The available molecular methods developed to characterize and type strains have not been useful for assigning isolates to the described species, creating the need for molecular markers capable of distinguishing genetically isolated groups. Here, we describe a PCR and sequencing-based microsatellite marker system that is stable, easy to assay, adaptable to large series of isolates, and discriminatory enough to be used as a typing system in identifying the three proposed species of P. brasiliensis. In addition, this system provides an unambiguous tool for strain discrimination between two (S1 and PS2) of the three phylogenetic species. PMID:16757613

  1. Cryptic species of Paracoccidioides brasiliensis: impact on paracoccidioidomycosis immunodiagnosis

    PubMed Central

    Machado, Gabriel Capella; Moris, Daniela Vanessa; Arantes, Thales Domingos; Silva, Luciane Regina Franciscone; Theodoro, Raquel Cordeiro; Mendes, Rinaldo Pôncio; Vicentini, Adriana Pardini; Bagagli, Eduardo

    2013-01-01

    We aimed to evaluate whether the occurrence of cryptic species of Paracoccidioides brasiliensis, S1, PS2, PS3 and Paracoccidioides lutzii, has implications in the immunodiagnosis of paracoccidioidomycosis (PCM). Small quantities of the antigen gp43 were found in culture filtrates of P. lutzii strains and this molecule appeared to be more variable within P. lutzii because the synonymous-nonsynonymous mutation rate was lower, indicating an evolutionary process different from that of the remaining genotypes. The production of gp43 also varied between isolates belonging to the same species, indicating that speciation events are important, but not sufficient to fully explain the diversity in the production of this antigen. The culture filtrate antigen AgEpm83, which was obtained from a PS3 isolate, showed large quantities of gp43 and reactivity by immunodiffusion assays, similar to the standard antigen (AgB-339) from an S1 isolate. Furthermore, AgEpm83 was capable of serologically differentiating five serum samples from patients from the Botucatu and Jundiaí regions. These patients had confirmed PCM but, were non-reactive to the standard antigen, thus demonstrating an alternative for serological diagnosis in regions in which S1 and PS2 occur. We also emphasise that it is not advisable to use a single antigen preparation to diagnose PCM, a disease that is caused by highly diverse pathogens. PMID:23903981

  2. Cryptic species of Paracoccidioides brasiliensis: impact on paracoccidioidomycosis immunodiagnosis.

    PubMed

    Machado, Gabriel Capella; Moris, Daniela Vanessa; Arantes, Thales Domingos; Silva, Luciane Regina Franciscone; Theodoro, Raquel Cordeiro; Mendes, Rinaldo Pôncio; Vicentini, Adriana Pardini; Bagagli, Eduardo

    2013-08-01

    We aimed to evaluate whether the occurrence of cryptic species of Paracoccidioides brasiliensis, S1, PS2, PS3 and Paracoccidioides lutzii, has implications in the immunodiagnosis of paracoccidioidomycosis (PCM). Small quantities of the antigen gp43 were found in culture filtrates of P. lutzii strains and this molecule appeared to be more variable within P. lutzii because the synonymous-nonsynonymous mutation rate was lower, indicating an evolutionary process different from that of the remaining genotypes. The production of gp43 also varied between isolates belonging to the same species, indicating that speciation events are important, but not sufficient to fully explain the diversity in the production of this antigen. The culture filtrate antigen AgEpm83, which was obtained from a PS3 isolate, showed large quantities of gp43 and reactivity by immunodiffusion assays, similar to the standard antigen (AgB-339) from an S1 isolate. Furthermore, AgEpm83 was capable of serologically differentiating five serum samples from patients from the Botucatu and Jundiaí regions. These patients had confirmed PCM but, were non-reactive to the standard antigen, thus demonstrating an alternative for serological diagnosis in regions in which S1 and PS2 occur. We also emphasise that it is not advisable to use a single antigen preparation to diagnose PCM, a disease that is caused by highly diverse pathogens. PMID:23903981

  3. Detection of Melanin-Like Pigments in the Dimorphic Fungal Pathogen Paracoccidioides brasiliensis In Vitro and during Infection

    PubMed Central

    Gómez, Beatriz L.; Nosanchuk, Joshua D.; Díez, Soraya; Youngchim, Sirida; Aisen, Philip; Cano, Luz E.; Restrepo, Angela; Casadevall, Arturo; Hamilton, Andrew J.

    2001-01-01

    Melanins are implicated in the pathogenesis of several human diseases, including some microbial infections. In this study, we analyzed whether the conidia and the yeasts of the thermally dimorphic fungal pathogen Paracoccidioides brasiliensis produce melanin or melanin-like compounds in vitro and during infection. Growth of P. brasiliensis mycelia on water agar alone produced pigmented conidia, and growth of yeasts in minimal medium with l-3,4-dihydroxyphenylalanine (l-DOPA) produced pigmented cells. Digestion of the pigmented conidia and yeasts with proteolytic enzymes, denaturant, and hot concentrated acid yielded dark particles that were the same size and shape as their propagules. Immunofluorescence analysis demonstrated reactivity of a melanin-binding monoclonal antibody (MAb) with the pigmented conidia, yeasts, and particles. Electron spin resonance spectroscopy identified the yeast-derived particles produced in vitro when P. brasiliensis was grown in l-DOPA medium as a melanin-like compound. Nonreducing polyacrylamide gel electrophoresis of cytoplasmic yeast extract revealed a protein that catalyzed melanin synthesis from l-DOPA. The melanin binding MAb reacted with yeast cells in tissue from mice infected with P. brasiliensis. Finally digestion of infected tissue liberated particles reactive to the melanin binding MAb that had the typical morphology of P. brasiliensis yeasts. These data strongly suggest that P. brasiliensis propagules, both conidia and yeast cells, can produce melanin or melanin-like compounds in vitro and in vivo. Based on what is known about the function of melanin in the virulence of other fungi, this pigment may play a role in the pathogenesis of paracoccidioidomycosis. PMID:11500453

  4. Characterization of Paracoccidioides brasiliensis COX9, COX12, and COX16 respiratory genes.

    PubMed

    Bandeira, Simone C B; Nóbrega, Marina P

    2008-12-01

    Paracoccidioides brasiliensis is a thermo-dimorphic fungus that is the causative agent of paracoccidioidomyicosis (PCM), a human systemic granulomatous mycosis found in Latin America. Dimorphic transition from mycelium to yeast is required for establishing pathogenicity. Dimorphism is marked by changes in mitochondrial physiology, including modulation of respiration rate. In this work, we present the identification of three P. brasiliensis nuclear genes PbCOX9, PbCOX12, and PbCOX16 that code for structural subunits and a putative assembly facilitator (PbCOX16) of the mitochondrial cytochrome c oxidase (COX), the terminal enzyme complex of the respiratory chain. We measured their expression pattern during the dimorphic transition from mycelium to yeast and back by real-time reverse transcription quantitative polymerase chain reaction (real-time RT-qPCR). Our results show that messages from these genes increase during the mycelium to yeast transition and decrease during the opposite conversion. This result supports active mitochondrial participation in the transition. Heterologous complementation of the corresponding Saccharomyces cerevisiae null mutant with the PbCOX9 gene was successfully obtained. PMID:18672058

  5. DOSE RESPONSE EFFECT OF Paracoccidioides brasiliensis IN AN EXPERIMENTAL MODEL OF ARTHRITIS

    PubMed Central

    Loth, Eduardo Alexandre; Biazim, Samia Khalil; dos Santos, José Henrique Fermino Ferreira; Puccia, Rosana; Brancalhão, Rosimeire Costa; Chasco, Lucinéia de Fátima; Gandra, Rinaldo Ferreira; Simão, Rita de Cássia Garcia; de Franco, Marcello Fabiano

    2014-01-01

    Paracoccidioidomycosis (PCM) is caused by the dimorphic fungus Paracoccidioides brasiliensis (Pb) and corresponds to prevalent systemic mycosis in Latin America. The aim of the present work was to evaluate the dose response effect of the fungal yeast phase for the standardization of an experimental model of septic arthritis. The experiments were performed with groups of 14 rats that received doses of 103, 104 or 105 P. brasiliensis (Pb18) cells. The fungi were injected in 50 µL of phosphate-buffered saline (PBS) directly into the knee joints of the animals. The following parameters were analyzed in this work: the formation of swelling in knees infused with yeast cells and the radiological and anatomopathological alterations, besides antibody titer by ELISA. After 15 days of infection, signs of inflammation were evident. At 45 days, some features of damage and necrosis were observed in the articular cartilage. The systemic dissemination of the fungus was observed in 11% of the inoculated animals, and it was concluded that the experimental model is able to mimic articular PCM in humans and that the dose of 105 yeast cells can be used as standard in this model. PMID:24879005

  6. Saccharomyces cerevisiae Expressing Gp43 Protects Mice against Paracoccidioides brasiliensis Infection

    PubMed Central

    Assis-Marques, Mariana Aprigio; Oliveira, Aline Ferreira; Ruas, Luciana Pereira; dos Reis, Thaila Fernanda; Roque-Barreira, Maria Cristina; Coelho, Paulo Sergio Rodrigues

    2015-01-01

    The dimorphic fungus Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis (PCM). It is believed that approximately 10 million people are infected with the fungus and approximately 2% will eventually develop the disease. Unlike viral and bacterial diseases, fungal diseases are the ones against which there is no commercially available vaccine. Saccharomyces cerevisiae may be a suitable vehicle for immunization against fungal infections, as they require the stimulation of different arms of the immune response. Here we evaluated the efficacy of immunizing mice against PCM by using S. cerevisiae yeast expressing gp43. When challenged by inoculation of P. brasiliensis yeasts, immunized animals showed a protective profile in three different assays. Their lung parenchyma was significantly preserved, exhibiting fewer granulomas with fewer fungal cells than found in non-immunized mice. Fungal burden was reduced in the lung and spleen of immunized mice, and both organs contained higher levels of IL-12 and IFN-γ compared to those of non-vaccinated mice, a finding that suggests the occurrence of Th1 immunity. Taken together, our results indicate that the recombinant yeast vaccine represents a new strategy to confer protection against PCM. PMID:25790460

  7. Paracoccidioides brasiliensis PbP27 gene: knockdown procedures and functional characterization.

    PubMed

    Torres, Isaura; Hernandez, Orville; Tamayo, Diana; Muñoz, Jose F; García, Ana M; Gómez, Beatriz L; Restrepo, Angela; McEwen, Juan G

    2014-03-01

    Paracoccidioides brasiliensis PbP27 gene encodes a protein localized in both the fungal cytoplasm and cell wall. The parasitic infectious form produces this protein preferentially with the gene's expression varying between the fungus phylogenetic species. The biological function of the native p27 has yet to be determined during either growth of the yeast or host infection. Therefore, in this study, through the use of antisense RNA technology and Agrobacterium tumefaciens-mediated transformation, we generated mitotically stable PbP27 mutants (PbP27 aRNA) with the goal to evaluate the role of p27 in the biology and virulence of this fungus. PbP27 expression was reduced 60-75% in mutants, as determined by real-time PCR in correlation with a decrease in p27 expression. No alterations in the growth curve or in the ability to shift from mycelia to yeast or from yeast to mycelia were observed in PbP27 aRNA strains; however, we did observe a reduction in cell vitality. Moreover, a decrease in cell viability of PbP27 aRNA yeast cells after interaction with IFN-?-stimulated macrophages was detected. Based on these results, we propose that p27 plays a role in yeast cell architecture and represents one of the mechanisms employed by this fungus for its interaction with the monocyte/macrophage system. PMID:24118983

  8. Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry for Differentiation of the Dimorphic Fungal Species Paracoccidioides brasiliensis and Paracoccidioides lutzii

    PubMed Central

    Del Negro, Gilda M. B.; Grenfell, Rafaella C.; Vidal, Monica S. M.; Thomaz, Danilo Y.; de Figueiredo, Dulce S. Y.; Bagagli, Eduardo; Juliano, Luiz; Benard, Gil

    2015-01-01

    Isolates of Paracoccidioides brasiliensis and Paracoccidioides lutzii, previously characterized by molecular techniques, were identified for the first time by matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS). All isolates were correctly identified, with log score values of >2.0. Thus, MALDI-TOF MS is a new tool for differentiating species of the genus Paracoccidioides. PMID:25631803

  9. The pathogenic fungus Paracoccidioides brasiliensis exports extracellular vesicles containing highly immunogenic ?-Galactosyl epitopes.

    PubMed

    Vallejo, Milene C; Matsuo, Alisson L; Ganiko, Luciane; Medeiros, Lia C Soares; Miranda, Kildare; Silva, Luiz S; Freymüller-Haapalainen, Edna; Sinigaglia-Coimbra, Rita; Almeida, Igor C; Puccia, Rosana

    2011-03-01

    Exosome-like vesicles containing virulence factors, enzymes, and antigens have recently been characterized in fungal pathogens, such as Cryptococcus neoformans and Histoplasma capsulatum. Here, we describe extracellular vesicles carrying highly immunogenic ?-linked galactopyranosyl (?-Gal) epitopes in Paracoccidioides brasiliensis. P. brasiliensis is a dimorphic fungus that causes human paracoccidioidomycosis (PCM). For vesicle preparations, cell-free supernatant fluids from yeast cells cultivated in Ham's defined medium-glucose were concentrated in an Amicon ultrafiltration system and ultracentrifuged at 100,000 × g. P. brasiliensis antigens were present in preparations from phylogenetically distinct isolates Pb18 and Pb3, as observed in immunoblots revealed with sera from PCM patients. In an enzyme-linked immunosorbent assay (ELISA), vesicle components containing ?-Gal epitopes reacted strongly with anti-?-Gal antibodies isolated from both Chagas' disease and PCM patients, with Marasmius oreades agglutinin (MOA) (a lectin that recognizes terminal ?-Gal), but only faintly with natural anti-?-Gal. Reactivity was inhibited after treatment with ?-galactosidase. Vesicle preparations analyzed by electron microscopy showed vesicular structures of 20 to 200 nm that were labeled both on the surface and in the lumen with MOA. In P. brasiliensis cells, components carrying ?-Gal epitopes were found distributed on the cell wall, following a punctuated confocal pattern, and inside large intracellular vacuoles. Lipid-free vesicle fractions reacted with anti-?-Gal in ELISA only when not digested with ?-galactosidase, while reactivity with glycoproteins was reduced after ?-elimination, which is indicative of partial O-linked chain localization. Our findings open new areas to explore in terms of host-parasite relationships in PCM and the role played in vivo by vesicle components and ?-galactosyl epitopes. PMID:21216942

  10. The Pathogenic Fungus Paracoccidioides brasiliensis Exports Extracellular Vesicles Containing Highly Immunogenic ?-Galactosyl Epitopes?

    PubMed Central

    Vallejo, Milene C.; Matsuo, Alisson L.; Ganiko, Luciane; Medeiros, Lia C. Soares; Miranda, Kildare; Silva, Luiz S.; Freymüller-Haapalainen, Edna; Sinigaglia-Coimbra, Rita; Almeida, Igor C.; Puccia, Rosana

    2011-01-01

    Exosome-like vesicles containing virulence factors, enzymes, and antigens have recently been characterized in fungal pathogens, such as Cryptococcus neoformans and Histoplasma capsulatum. Here, we describe extracellular vesicles carrying highly immunogenic ?-linked galactopyranosyl (?-Gal) epitopes in Paracoccidioides brasiliensis. P. brasiliensis is a dimorphic fungus that causes human paracoccidioidomycosis (PCM). For vesicle preparations, cell-free supernatant fluids from yeast cells cultivated in Ham's defined medium-glucose were concentrated in an Amicon ultrafiltration system and ultracentrifuged at 100,000 × g. P. brasiliensis antigens were present in preparations from phylogenetically distinct isolates Pb18 and Pb3, as observed in immunoblots revealed with sera from PCM patients. In an enzyme-linked immunosorbent assay (ELISA), vesicle components containing ?-Gal epitopes reacted strongly with anti-?-Gal antibodies isolated from both Chagas' disease and PCM patients, with Marasmius oreades agglutinin (MOA) (a lectin that recognizes terminal ?-Gal), but only faintly with natural anti-?-Gal. Reactivity was inhibited after treatment with ?-galactosidase. Vesicle preparations analyzed by electron microscopy showed vesicular structures of 20 to 200 nm that were labeled both on the surface and in the lumen with MOA. In P. brasiliensis cells, components carrying ?-Gal epitopes were found distributed on the cell wall, following a punctuated confocal pattern, and inside large intracellular vacuoles. Lipid-free vesicle fractions reacted with anti-?-Gal in ELISA only when not digested with ?-galactosidase, while reactivity with glycoproteins was reduced after ?-elimination, which is indicative of partial O-linked chain localization. Our findings open new areas to explore in terms of host-parasite relationships in PCM and the role played in vivo by vesicle components and ?-galactosyl epitopes. PMID:21216942

  11. Comparison between human and armadillo Paracoccidioides brasiliensis isolates by random amplified polymorphic DNA analysis.

    PubMed

    Sano, A; Tanaka, R; Yokoyama, K; Franco, M; Bagagli, E; Montenegro, M R; Mikami, Y; Miyaji, M; Nishimura, K

    Sixty-three Paracoccidioides brasiliensis isolates obtained from three nine-banded armadillos (Dasypus novemcinctus), one Amazonian armadillo's and 19 clinical isolates were compared by random amplified polymorphic DNA analysis with the primer OPG-19. The isolates were divided into three major clusters, I, II and III. Coincidences between human and armadillo isolates were observed in clusters I and II. Cluster III consisted only of armadillos' isolates. The results suggested that (I) humans may acquire P. brasiliensis infection by contact with armadillo's environment, (II) there may be P. brasiliensis genotypes peculiar to the animal, and (III) individual armadillos may be infected with P. brasiliensis cells with different genotypes. PMID:10353214

  12. Lipidomic Analysis of Extracellular Vesicles from the Pathogenic Phase of Paracoccidioides brasiliensis

    PubMed Central

    Longo, Larissa V. G.; Ganiko, Luciane; Lopes, Felipe G.; Matsuo, Alisson L.; Almeida, Igor C.; Puccia, Rosana

    2012-01-01

    Background Fungal extracellular vesicles are able to cross the cell wall and transport molecules that help in nutrient acquisition, cell defense, and modulation of the host defense machinery. Methodology/Principal Findings Here we present a detailed lipidomic analysis of extracellular vesicles released by Paracoccidioides brasiliensis at the yeast pathogenic phase. We compared data of two representative isolates, Pb3 and Pb18, which have distinct virulence profiles and phylogenetic background. Vesicle lipids were fractionated into different classes and analyzed by either electrospray ionization- or gas chromatography-mass spectrometry. We found two species of monohexosylceramide and 33 phospholipid species, including phosphatidylcholine, phosphatidylethanolamine, phosphatidic acid, phosphatidylserine, phosphatidylinositol, and phosphatidylglycerol. Among the phospholipid-bound fatty acids in extracellular vesicles, C181 predominated in Pb3, whereas C18:2 prevailed in Pb18. The prevalent sterol in Pb3 and Pb18 vesicles was brassicasterol, followed by ergosterol and lanosterol. Inter-isolate differences in sterol composition were observed, and also between extracellular vesicles and whole cells. Conclusions/Significance The extensive lipidomic analysis of extracellular vesicles from two P. brasiliensis isolates will help to understand the composition of these fungal components/organelles and will hopefully be useful to study their biogenesis and role in host-pathogen interactions. PMID:22745761

  13. rPbPga1 from Paracoccidioides brasiliensis Activates Mast Cells and Macrophages via NFkB

    PubMed Central

    Valim, Clarissa Xavier Resende; da Silva, Elaine Zayas Marcelino; Assis, Mariana Aprigio; Fernandes, Fabricio Freitas; Coelho, Paulo Sergio Rodrigues; Oliver, Constance; Jamur, Maria Célia

    2015-01-01

    Background The fungus Paracoccidioides brasiliensis is the leading etiological agent of paracoccidioidomycosis (PCM), a systemic granulomatous disease that typically affects the lungs. Cell wall components of P. brasiliensis interact with host cells and influence the pathogenesis of PCM. In yeast, many glycosylphosphatidylinositol (GPI)-anchored proteins are important in the initial contact with the host, mediating host-yeast interactions that culminate with the disease. PbPga1 is a GPI anchored protein located on the surface of the yeast P. brasiliensis that is recognized by sera from PCM patients. Methodology/Principal Findings Endogenous PbPga1 was localized to the surface of P. brasiliensis yeast cells in the lungs of infected mice using a polyclonal anti-rPbPga1 antibody. Furthermore, macrophages stained with anti-CD38 were associated with P. brasiliensis containing granulomas. Additionally, rPbPga1 activated the transcription factor NFkB in the macrophage cell line Raw 264.7 Luc cells, containing the luciferase gene downstream of the NFkB promoter. After 24 h of incubation with rPbPga1, alveolar macrophages from BALB/c mice were stimulated to release TNF-?, IL-4 and NO. Mast cells, identified by toluidine blue staining, were also associated with P. brasiliensis containing granulomas. Co-culture of P. Brasiliensis yeast cells with RBL-2H3 mast cells induced morphological changes on the surface of the mast cells. Furthermore, RBL-2H3 mast cells were degranulated by P. brasiliensis yeast cells, but not by rPbPga1, as determined by the release of beta-hexosaminidase. However, RBL-2H3 cells activated by rPbPga1 released the inflammatory interleukin IL-6 and also activated the transcription factor NFkB in GFP-reporter mast cells. The transcription factor NFAT was not activated when the mast cells were incubated with rPbPga1. Conclusions/Significance The results indicate that PbPga1 may act as a modulator protein in PCM pathogenesis and serve as a useful target for additional studies on the pathogenesis of P. brasiliensis. PMID:26317855

  14. Expression of Paracoccidioides brasiliensis AMY1 in a Histoplasma capsulatum amy1 Mutant, Relates an ?-(1,4)-Amylase to Cell Wall ?-(1,3)-Glucan Synthesis

    PubMed Central

    Camacho, Emma; Sepulveda, Victoria E.; Goldman, William E.; San-Blas, Gioconda; Niño-Vega, Gustavo A.

    2012-01-01

    In the cell walls of the pathogenic yeast phases of Paracoccidioides brasiliensis, Blastomyces dermatitidis and Histoplasma capsulatum, the outer ?-(1,3)-glucan layer behaves as a virulence factor. In H. capsulatum, an ?-(1,4)-amylase gene (AMY1) is essential for the synthesis of this polysaccharide, hence related to virulence. An orthologous gene to H. capsulatum AMY1 was identified in P. brasiliensis and also labeled AMY1. P. brasiliensis AMY1 transcriptional levels were increased during the yeast phase, which correlates with the presence of ?-(1,3)-glucan as the major yeast cell wall polysaccharide. Complementation of a H. capsulatum amy1 mutant strain with P. brasiliensis AMY1, suggests that P. brasiliensis Amy1p may play a role in the synthesis of cell wall ?-(1,3)-glucan. To study some biochemical properties of P. brasiliensis Amy1p, the enzyme was overexpressed, purified and studied its activity profile with starch and amylopeptin. It showed a relatively higher hydrolyzing activity on amylopeptin than starch, producing oligosaccharides from 4 to 5 glucose residues. Our findings show that P. brasiliensis Amy1p produces maltooligosaccharides which may act as a primer molecule for the fungal cell wall ?-(1,3)-glucan biosynthesis by Ags1p. PMID:23185578

  15. [In vitro infection by different strains of Paracoccidioides brasiliensis].

    PubMed

    Canteros, C E; Soria, M A; Rivas, M C; Pérez, C; Tous, M; Lee, W; Rodero, L; Davel, G

    2000-01-01

    We analyzed the in vitro infection process by P. brasiliensis and the effect of extracellular factor(s) produced on monolayers of mammalian Vero cell lines. The yeast phase of four strains was studied: B339 (avirulent or slightly virulent), U, (intermediate virulence), 93745 and 63265 (both highly virulent). Strains of intermediate and high virulence had higher adherence at first contact (about 16%). Strain B339 had a slower adherence at first contact (8%) than the others during the same period. The production of extracellular proteases, soluble extracellular factor(s) and extracellular antigen gP43 showed no correlation with the in vitro physiopathogenicity of the analyzed strains. We demonstrate that the Vero model presented in this paper is a suitable system to study infection and virulence in vitro. We are currently assessing its usefulness as a tool for the analysis of the interaction between pathogen, host and antifungal agents. PMID:11008702

  16. Low Concentrations of Hydrogen Peroxide or Nitrite Induced of Paracoccidioides brasiliensis Cell Proliferation in a Ras-Dependent Manner

    PubMed Central

    Haniu, Ana Eliza Coronel Janu; Maricato, Juliana Terzi; Mathias, Pedro Paulo Moraes; Castilho, Daniele Gonçalves; Miguel, Rodrigo Bernardi; Monteiro, Hugo Pequeno; Puccia, Rosana; Batista, Wagner Luiz

    2013-01-01

    Paracoccidioides brasiliensis, a causative agent of paracoccidioidomycosis (PCM), should be able to adapt to dramatic environmental changes inside the infected host after inhalation of air-borne conidia and transition to pathogenic yeasts. Proteins with antioxidant functions may protect fungal cells against reactive oxygen (ROS) and nitrogen (RNS) species generated by phagocytic cells, thus acting as potential virulence factors. Ras GTPases are involved in stress responses, cell morphology, and differentiation in a range of organisms. Ras, in its activated form, interacts with effector proteins and can initiate a kinase cascade. In lower eukaryotes, Byr2 kinase represents a Ras target. The present study investigated the role of Ras in P. brasiliensis after in vitro stimulus with ROS or RNS. We have demonstrated that low concentrations of H2O2 (0.1 mM) or NO2 (0.1–0.25 µM) stimulated P. brasiliensis yeast cell proliferation and that was not observed when yeast cells were pre-incubated with farnesyltransferase inhibitor. We constructed an expression plasmid containing the Byr2 Ras-binding domain (RBD) fused with GST (RBD-Byr2-GST) to detect the Ras active form. After stimulation with low concentrations of H2O2 or NO2, the Ras active form was observed in fungal extracts. Besides, NO2 induced a rapid increase in S-nitrosylated Ras levels. This alternative posttranslational modification of Ras, probably in residue Cys123, would lead to an exchange of GDP for GTP and consequent GTPase activation in P. brasiliensis. In conclusion, low concentrations of H2O2 or NO2 stimulated P. brasiliensis proliferation through Ras activation. PMID:23922749

  17. Data in support of quantitative proteomics to identify potential virulence regulators in Paracoccidioides brasiliensis isolates.

    PubMed

    Tashima, Alexandre Keiji; Castilho, Daniele Gonçalves; Chaves, Alison Felipe Alencar; Xander, Patricia; Zelanis, André; Batista, Wagner Luiz

    2015-12-01

    Paracoccidioides genus are the etiologic agents of paracoccidioidomycosis (PCM), a systemic mycosis endemic in Latin America. Few virulence factors have been identified in these fungi. This paper describes support data from the quantitative proteomics of Paracoccidioides brasiliensis attenuated and virulent isolates [1]. The protein compositions of two isolates of the Pb18 strain showing distinct infection profiles were quantitatively assessed by stable isotopic dimethyl labeling and proteomic analysis. The mass spectrometry and the analysis dataset have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with identifier PXD000804. PMID:26501084

  18. Data in support of quantitative proteomics to identify potential virulence regulators in Paracoccidioides brasiliensis isolates

    PubMed Central

    Tashima, Alexandre Keiji; Castilho, Daniele Gonçalves; Chaves, Alison Felipe Alencar; Xander, Patricia; Zelanis, André; Batista, Wagner Luiz

    2015-01-01

    Paracoccidioides genus are the etiologic agents of paracoccidioidomycosis (PCM), a systemic mycosis endemic in Latin America. Few virulence factors have been identified in these fungi. This paper describes support data from the quantitative proteomics of Paracoccidioides brasiliensis attenuated and virulent isolates [1]. The protein compositions of two isolates of the Pb18 strain showing distinct infection profiles were quantitatively assessed by stable isotopic dimethyl labeling and proteomic analysis. The mass spectrometry and the analysis dataset have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with identifier PXD000804. PMID:26501084

  19. Paracoccidioides brasiliensis Interferes on Dendritic Cells Maturation by Inhibiting PGE2 Production

    PubMed Central

    2015-01-01

    Paracoccidioidomycosis (PCM) is a systemic mycosis, endemic in most Latin American countries, especially in Brazil, whose etiologic agent is the thermodimorphic fungus of the genus Paracoccidioides, comprising cryptic species of Paracoccidioides brasiliensis, S1, PS2, PS3 and Paracoccidioides lutzii. The mechanisms involved in the initial interaction of the fungus with cells of the innate immune response, as dendritic cells (DCs), deserve to be studied. Prostaglandins (PGs) are eicosanoids that play an important role in modulating functions of immune cells including DCs. Here we found that human immature DCs derived from the differentiation of monocytes cultured with GM-CSF and IL-4 release substantial concentrations of PGE2, which, however, were significantly inhibited after challenge with P. brasiliensis. In vitro blocking of pattern recognition receptors (PRRs) by monoclonal antibodies showed the involvement of mannose receptor (MR) in PGE2 inhibition by the fungus. In addition, phenotyping assays showed that after challenge with the fungus, DCs do not change their phenotype of immature cells to mature ones, as well as do not produce IL-12 p70 or adequate concentrations of TNF-?. Assays using exogenous PGE2 confirmed an association between PGE2 inhibition and failure of cells to phenotypically mature in response to P. brasiliensis. We conclude that a P. brasiliensis evasion mechanism exists associated to a dysregulation on DC maturation. These findings may provide novel information for the understanding of the complex interplay between the host and this fungus. PMID:25793979

  20. Paracoccidioides brasiliensis interferes on dendritic cells maturation by inhibiting PGE2 production.

    PubMed

    Fernandes, Reginaldo K; Bachiega, Tatiana F; Rodrigues, Daniela R; Golim, Marjorie de A; Dias-Melicio, Luciane A; Balderramas, Helanderson de A; Kaneno, Ramon; Soares, Ângela M V C

    2015-01-01

    Paracoccidioidomycosis (PCM) is a systemic mycosis, endemic in most Latin American countries, especially in Brazil, whose etiologic agent is the thermodimorphic fungus of the genus Paracoccidioides, comprising cryptic species of Paracoccidioides brasiliensis, S1, PS2, PS3 and Paracoccidioides lutzii. The mechanisms involved in the initial interaction of the fungus with cells of the innate immune response, as dendritic cells (DCs), deserve to be studied. Prostaglandins (PGs) are eicosanoids that play an important role in modulating functions of immune cells including DCs. Here we found that human immature DCs derived from the differentiation of monocytes cultured with GM-CSF and IL-4 release substantial concentrations of PGE2, which, however, were significantly inhibited after challenge with P. brasiliensis. In vitro blocking of pattern recognition receptors (PRRs) by monoclonal antibodies showed the involvement of mannose receptor (MR) in PGE2 inhibition by the fungus. In addition, phenotyping assays showed that after challenge with the fungus, DCs do not change their phenotype of immature cells to mature ones, as well as do not produce IL-12 p70 or adequate concentrations of TNF-?. Assays using exogenous PGE2 confirmed an association between PGE2 inhibition and failure of cells to phenotypically mature in response to P. brasiliensis. We conclude that a P. brasiliensis evasion mechanism exists associated to a dysregulation on DC maturation. These findings may provide novel information for the understanding of the complex interplay between the host and this fungus. PMID:25793979

  1. A 32-Kilodalton Hydrolase Plays an Important Role in Paracoccidioides brasiliensis Adherence to Host Cells and Influences Pathogenicity?

    PubMed Central

    Hernández, Orville; Almeida, Agostinho J.; Gonzalez, Angel; Garcia, Ana Maria; Tamayo, Diana; Cano, Luz Elena; Restrepo, Angela; McEwen, Juan G.

    2010-01-01

    One of the most crucial events during infection with the dimorphic fungus Paracoccidioides brasiliensis is adhesion to pulmonary epithelial cells, a pivotal step in the establishment of disease. In this study, we have evaluated the relevance of a 32-kDa protein, a putative adhesion member of the haloacid dehalogenase (HAD) superfamily of hydrolases, in the virulence of this fungus. Protein sequence analyses have supported the inclusion of PbHad32p as a hydrolase and have revealed a conserved protein only among fungal dimorphic and filamentous pathogens that are closely phylogenetically related. To evaluate its role during the host-pathogen interaction, we have generated mitotically stable P. brasiliensis HAD32 (PbHAD32) antisense RNA (aRNA) strains with consistently reduced gene expression. Knockdown of PbHAD32 did not alter cell vitality or viability but induced morphological alterations in yeast cells. Moreover, yeast cells with reduced PbHAD32 expression were significantly affected in their capacity to adhere to human epithelial cells and presented decreased virulence in a mouse model of infection. These data support the hypothesis that PbHad32p binds to extracellular matrix (ECM) proteins and modulates the initial immune response for evasion of host defenses. Our findings point to PbHAD32 as a novel virulence factor active during the initial interaction with host cells in P. brasiliensis. PMID:20876288

  2. Characterization of PbPga1, an Antigenic GPI-Protein in the Pathogenic Fungus Paracoccidioides brasiliensis

    PubMed Central

    Valim, Clarissa X. R.; Basso, Luiz Roberto; dos Reis Almeida, Fausto B.; Reis, Thaila Fernanda; Damásio, André Ricardo Lima; Arruda, Luisa Karla; Martinez, Roberto; Roque-Barreira, Maria Cristina; Oliver, Constance; Jamur, Maria Célia; Coelho, Paulo Sergio Rodrigues

    2012-01-01

    Paracoccidioides brasiliensis is the etiologic agent of paracoccidioidomycosis (PCM), one of the most prevalent mycosis in Latin America. P. brasiliensis cell wall components interact with host cells and influence the pathogenesis of PCM. Cell wall components, such as glycosylphosphatidylinositol (GPI)-proteins play a critical role in cell adhesion and host tissue invasion. Although the importance of GPI-proteins in the pathogenesis of other medically important fungi is recognized, little is known about their function in P. brasiliensis cells and PCM pathogenesis. We cloned the PbPga1 gene that codifies for a predicted GPI-anchored glycoprotein from the dimorphic pathogenic fungus P. brasiliensis. PbPga1 is conserved in Eurotiomycetes fungi and encodes for a protein with potential glycosylation sites in a serine/threonine-rich region, a signal peptide and a putative glycosylphosphatidylinositol attachment signal sequence. Specific chicken anti-rPbPga1 antibody localized PbPga1 on the yeast cell surface at the septum between the mother cell and the bud with stronger staining of the bud. The exposure of murine peritoneal macrophages to rPbPga1 induces TNF-? release and nitric oxide (NO) production by macrophages. Furthermore, the presence of O-glycosylation sites was demonstrated by ?-elimination under ammonium hydroxide treatment of rPbPga1. Finally, sera from PCM patients recognized rPbPga1 by Western blotting indicating the presence of specific antibodies against rPbPga1. In conclusion, our findings suggest that the PbPga1gene codifies for a cell surface glycoprotein, probably attached to a GPI-anchor, which may play a role in P. brasiliensis cell wall morphogenesis and infection. The induction of inflammatory mediators released by rPbPga1 and the reactivity of PCM patient sera toward rPbPga1 imply that the protein favors the innate mechanisms of defense and induces humoral immunity during P. brasiliensis infection. PMID:23024763

  3. New Developments of RNAi in Paracoccidioides brasiliensis: Prospects for High-Throughput, Genome-Wide, Functional Genomics

    PubMed Central

    Goes, Tercio; Bailão, Elisa Flavia L. C.; Correa, Cristiane R.; Bozzi, Adriana; Santos, Luara I.; Gomes, Dawidson A.; Soares, Celia M. A.; Goes, Alfredo M.

    2014-01-01

    Background The Fungal Genome Initiative of the Broad Institute, in partnership with the Paracoccidioides research community, has recently sequenced the genome of representative isolates of this human-pathogen dimorphic fungus: Pb18 (S1), Pb03 (PS2) and Pb01. The accomplishment of future high-throughput, genome-wide, functional genomics will rely upon appropriate molecular tools and straightforward techniques to streamline the generation of stable loss-of-function phenotypes. In the past decades, RNAi has emerged as the most robust genetic technique to modulate or to suppress gene expression in diverse eukaryotes, including fungi. These molecular tools and techniques, adapted for RNAi, were up until now unavailable for P. brasiliensis. Methodology/Principal Findings In this paper, we report Agrobacterium tumefaciens mediated transformation of yeast cells for high-throughput applications with which higher transformation frequencies of 150±24 yeast cell transformants per 1×106 viable yeast cells were obtained. Our approach is based on a bifunctional selective marker fusion protein consisted of the Streptoalloteichus hindustanus bleomycin-resistance gene (Shble) and the intrinsically fluorescent monomeric protein mCherry which was codon-optimized for heterologous expression in P. brasiliensis. We also report successful GP43 gene knock-down through the expression of intron-containing hairpin RNA (ihpRNA) from a Gateway-adapted cassette (cALf) which was purpose-built for gene silencing in a high-throughput manner. Gp43 transcript levels were reduced by 73.1±22.9% with this approach. Conclusions/Significance We have a firm conviction that the genetic transformation technique and the molecular tools herein described will have a relevant contribution in future Paracoccidioides spp. functional genomics research. PMID:25275433

  4. Estradiol binds to a receptor-like cytosol binding protein and initiates a biological response in Paracoccidioides brasiliensis.

    PubMed Central

    Loose, D S; Stover, E P; Restrepo, A; Stevens, D A; Feldman, D

    1983-01-01

    Paracoccidioidomycosis, a disease caused by Paracoccidioides brasiliensis, which is endemic to Latin America, is much more common in men than women, suggesting a role for hormonal factors. We recently showed that two other yeasts possess steroid binding proteins and postulated that these receptor-like molecules represented a mechanism by which the hormonal milieu of the host might influence an infecting pathogen. Therefore, we examined P. brasiliensis for a sex steroid binding protein. Because tritiated steroids rapidly dissociated from the other fungal binding proteins, we developed a fast binding method with Sephadex G-50 microcolumns speeded by centrifugation. This method detected specific binding of [3H]estradiol in P. brasiliensis cytosol. Other tritiated steroid hormones, including testosterone and corticosterone, failed to exhibit specific binding. Scatchard analysis of [3H]estradiol binding showed an apparent dissociation constant (Kd) of 1.7 X 10(-8) M and a maximal binding capacity (Nmax) of 235 fmol/mg of protein. Susceptibility to trypsin indicated the binding site was protein in nature. The protein had a Stokes radius of approximately equal to 32 A by HPLC exclusion column and a sedimentation coefficient of 4.4 S by sucrose gradient, consistent with an apparent Mr of approximately equal to 60,000. Competition experiments revealed that estrone, estriol, and progesterone had 25% of the affinity of estradiol, whereas diethylstilbestrol, androgens, and corticosteroids had low affinity. Investigation of steroid hormone actions in P. brasiliensis indicated that estradiol inhibited the fungal transformation from mycelial form to yeast form, the initial step of infection. This suppressive effect was dose-dependent and not found with testosterone. We hypothesize that endogenous estrogens in the host, acting through the cytosol binding protein in the fungus, inhibit mycelial-to-yeast transformation, thus explaining the resistance of women to paracoccidioidomycosis. PMID:6584880

  5. The habitat of Paracoccidioides brasiliensis: how far from solving the riddle?

    PubMed

    Restrepo, A; McEwen, J G; Castañeda, E

    2001-06-01

    When trying to understand the pathophysiology of any infectious agent, one key piece of information is the determination of its habitat. In the case of Paracoccidioides brasiliensis, the precise location of the fungus' environmental niche remains undefined despite the efforts of various research groups. This review summarizes recent studies on the ecology of P. brasiliensis and certain facets of paracoccidioidomycosis. Studies on the juvenile form of paracoccidioidomycosis in children less than 13 years of age, the characterization of the ecological factors in the 'reservarea' where the infection is acquired and the presence of P. brasiliensis in the nine-banded armadillo (Dasypus novemcinctus), are all helping to pinpoint the microniche of this pathogen. The application of molecular biology techniques based on the amplification of nucleic acids will also hopefully help in establishing the precise habitat of P. brasiliensis. PMID:11446526

  6. Paracoccidioides brasiliensis-stimulated human gamma/delta T cells support antibody production by B cells.

    PubMed Central

    Munk, M E; Fazioli, R A; Calich, V L; Kaufmann, S H

    1995-01-01

    Paracoccidioidomycosis patients show hyperactive humoral immune responses. Consequently, we investigated whether cytokines in supernatants from Paracoccidioides brasiliensis-stimulated gamma/delta T cells support B-cell activation. We detected proliferation of B cells and increased immunoglobulin M (IgM) and IgG production. Thus, gamma/delta T cells may participate in polyclonal B-cell activation during paracoccidioidomycosis. PMID:7890430

  7. Pathogenicities and GP43kDa gene of three Paracoccidioides brasiliensis isolates originated from a nine-banded armadillo (Dasypus novemcinctus).

    PubMed

    Sano, A; Defaveri, J; Tanaka, R; Yokoyama, K; Kurita, N; Franco, M; Coelho, K I; Bagagli, E; Montenegro, M R; Miyaji, M; Nishimura, K

    We studied three different isolates of Paracoccidioides brasiliensis obtained from the mesenteric lymph node (D3LY1), the spleen (D3S1) and the liver (D3LIV1) of the same armadillo (Dasypus novemcinctus). Pulmonal inflammatory area was evaluated by intravenous inoculation of 10(6) yeast cells of each isolates in young, male, ddY mice. Moreover, the partial sequence of GP43kDa gene of P. brasiliensis was analyzed. The lung inflammatory area was greater in animals inoculated with isolate D3S1. The partial sequence of GP43kDa gene indicated that isolate D3S1 is different from isolates D3LY1 and D3LIV1. This study suggested that the same armadillo might be susceptible to multiple P. brasiliensis isolates simultaneously. PMID:10481285

  8. Nitric Oxide Participation in the Fungicidal Mechanism of Gamma Interferon-Activated Murine Macrophages against Paracoccidioides brasiliensis Conidia

    PubMed Central

    Gonzalez, Angel; de Gregori, Waldemar; Velez, Diana; Restrepo, Angela; Cano, Luz E.

    2000-01-01

    Paracoccidioidomycosis, a systemic mycosis restricted to Latin America and produced by the dimorphic fungus Paracoccidioides brasiliensis, is probably acquired by inhalation of conidia produced by the mycelial form. The macrophage (M?) represents the major cell defense against this pathogen; when activated with gamma interferon (IFN-?), murine M?s kill the fungus by an oxygen-independent mechanism. Our goal was to determine the role of nitric oxide in the fungicidal effect of M?s on P. brasiliensis conidia. The results revealed that IFN-?-activated murine M?s inhibited the conidium-to-yeast transformation process in a dose-dependent manner; maximal inhibition was observed in M?s activated with 50 U/ml and incubated for 96 h at 37°C. When M?s were activated with 150 to 200 U of cytokine per ml, the number of CFU was 70% lower than in nonactivated controls, indicating that there was a fungicidal effect. The inhibitory effect was reversed by the addition of anti-IFN-? monoclonal antibodies. Activation by IFN-? also enhanced M? nitric oxide production, as revealed by increasing NO2 values (8 ± 3 ?M in nonactivated M?s versus 43 ± 13 ?M in activated M?s). The neutralization of IFN-? also reversed nitric oxide production at basal levels (8 ± 5 ?M). Additionally, we found that there was a significant inverse correlation (r = ?0.8975) between NO2? concentration and transformation of P. brasiliensis conidia. Additionally, treatment with any of the three different nitric oxide inhibitors used (arginase, NG-monomethyl-l-arginine, and aminoguanidine), reverted the inhibition of the transformation process with 40 to 70% of intracellular yeast and significantly reduced nitric oxide production. These results show that IFN-?-activated murine M?s kill P. brasiliensis conidia through the l-arginine–nitric oxide pathway. PMID:10768942

  9. Purification and Partial Characterization of a Paracoccidioides brasiliensis Protein with Capacity To Bind to Extracellular Matrix Proteins

    PubMed Central

    González, Angel; Gómez, Beatriz L.; Diez, Soraya; Hernández, Orville; Restrepo, Angela; Hamilton, Andrew J.; Cano, Luz E.

    2005-01-01

    Microorganisms adhere to extracellular matrix proteins by means of their own surface molecules. Paracoccidioides brasiliensis conidia have been shown to be capable of interacting with extracellular matrix proteins. We aimed at determining the presence of fungal proteins that could interact with extracellular matrix protein and, if found, attempt their purification and characterization. Various extracts were prepared from P. brasiliensis mycelial and yeast cultures (total homogenates, ?-mercaptoethanol, and sodium dodecyl sulfate [SDS] extracts) and analyzed by ligand affinity assays with fibronectin, fibrinogen and laminin. Two polypeptides were detected in both fungal forms. SDS extracts that interacted with all the extracellular matrix protein were tested; their molecular masses were 19 and 32 kDa. Analysis of the N-terminal amino acid sequence of the purified 32-kDa mycelial protein showed substantial homology with P. brasiliensis, Histoplasma capsulatum, and Neurospora crassa hypothetical proteins. Additionally, a monoclonal antibody (MAb) produced against this protein recognized the 32-kDa protein in the SDS extracts of both fungal forms for immunoblot. Immunofluorescence analysis revealed that this MAb reacted not only with mycelia and yeast cells, but also with conidia, indicating that this protein was shared by the three fungal propagules. By immunoelectron microscopy, this protein was detected in the cell walls and in the cytoplasm. Both the 32-kDa purified protein and MAb inhibited the adherence of conidia to the three extracellular matrix proteins in a dose-dependent manner. These findings demonstrate the presence of two polypeptides capable of interacting with extracellular matrix proteins on the surface of P. brasiliensis propagules, indicating that there may be common receptors for laminin, fibronectin, and fibrinogen. These proteins would be crucial for initial conidial adherence and perhaps also in dissemination of paracoccidioidomycosis. PMID:15784595

  10. Participation of dectin-1 receptor on NETs release against Paracoccidioides brasiliensis: Role on extracellular killing.

    PubMed

    Bachiega, Tatiana Fernanda; Dias-Melicio, Luciane Alarcão; Fernandes, Reginaldo Keller; de Almeida Balderramas, Helanderson; Rodrigues, Daniela Ramos; Ximenes, Valdecir Farias; de Campos Soares, Ângela Maria Victoriano

    2016-02-01

    Paracoccidioides brasiliensis is a dimorphic fungus from the Paracoccidioides genus, which is the causative agent of paracoccidioidomycosis, a chronic, subacute or acute mycosis, with visceral and cutaneous involvement. This disease that is acquired through inhalation primarily attacks the lungs but, can spread to other organs. Phagocytic cells as neutrophils play an important role during innate immune response against this fungus, but studies on antifungal activities of these cells are scarce. In addition to their ability to eliminate pathogens by phagocytosis and antimicrobial secretions, neutrophils can trap and kill microorganisms by release of extracellular structures composed by DNA and antimicrobial proteins, called neutrophil extracellular traps (NETs). Here, we provide evidence that P. brasiliensis virulent strain (P. brasiliensis 18) induces NETs release. These structures were well evidenced by scanning electron microscopy, and specific NETs compounds such as histone, elastase and DNA were shown by confocal microscopy. In addition, we have shown that dectin-1 receptor is the main PRR to which fungus binds to induce NETS release. Fungi were ensnared by NETs, denoting the role of these structures in confining the fungus, avoiding dissemination. NETs were also shown to be involved in fungus killing, since fungicidal activity detected before and mainly after neutrophils activation with TNF-?, IFN-? and GM-CSF was significantly inhibited by cocultures treatment with DNAse. PMID:26416210

  11. Diversity in Paracoccidioides brasiliensis. The PbGP43 gene as a genetic marker.

    PubMed

    Puccia, Rosana; McEwen, Juan G; Cisalpino, Patrícia S

    2008-01-01

    Paracoccidioides brasiliensis is a temperature-dependent dimorphic fungus and the agent of paracoccidioidomycosis (PCM), which is prevalent in rural workers of Latin American countries. Until a decade ago, most of the studies involving P. brasiliensis used clinical isolates, since environmental samples from soil are difficult to obtain. More recently, P. brasiliensis has been isolated from infected wild and domestic animals, especially from the nine-banded armadillo Dasypus novemcinctus in Brazil. Over the years, diversity within the species has been observed at several phenotypic levels. The present review will discuss the reports focusing on genetic polymorphism, which culminated with the detection of P. brasiliensis phylogenetic species as a result of a multilocus study. Polymorphism in the PbGP43 gene is detailed. This gene encodes fungal glycoprotein gp43, a dominant P. brasiliensis antigen largely studied in the last two decades for its importance in diagnosis, immune protection, and adhesive properties to extracellular matrix-associated proteins. Fungal traits associated with genetic groups are discussed. PMID:18777634

  12. Seroepidemiology of Paracoccidioides brasiliensis infection in horses from Rio Grande do Sul, Brazil

    PubMed Central

    Albano, Ana Paula Neuschrank; Klafke, Gabriel Baracy; Brandolt, Tchana Martinez; Da Hora, Vanusa Pousada; Nogueira, Carlos Eduardo Wayne; Xavier, Melissa Orzechowski; Meireles, Mário Carlos Araújo

    2015-01-01

    Paracoccidioides brasiliensis is the etiological agent of the major systemic mycosis in Brazil, called paracoccidioidomycosis. Although the Rio Grande do Sul is considered an endemic area of the disease, there are few studies on the ecology of P. brasiliensis in the state. Therefore, this study aimed to evaluate the infection of P. brasiliensis in horses from the mesoregion of Southwest Riograndense, using these animals as sentinels. Serological techniques, such as double immunodiffusion in agar gel (AGID) and indirect ELISA, were performed to detect the anti-gp43 P. brasiliensis antibody in horses from five different farms in the region of Bagé, RS, Brazil. Serology was performed in 200 Pure Blood English horses up to two years of age that were born and raised exclusively at the farms. Of these horses, 12% had anti-gp43 antibodies according to the ELISA results, with rates ranging from 0 to 30% according to the farm of origin (p < 0.001). Based on the immunodiffusion results, all equine serum samples were negative. These results indicate the presence of the fungus P. brasiliensis in the middle region of the southwestern state of Rio Grande do Sul, Brazil. PMID:26273267

  13. Induction of antigen-specific T suppressor cells by soluble Paracoccidioides brasiliensis antigen.

    PubMed Central

    Jimenez-Finkel, B E; Murphy, J W

    1988-01-01

    In naturally acquired paracoccidioidomycosis, patients have depressed in vivo and in vitro cell-mediated immune (CMI) responses to Paracoccidioides brasiliensis antigen. In addition, it has been reported that these patients have significant levels of circulating paracoccidioidal antigen in their sera. The primary purpose of this investigation was to assess the effects of P. brasiliensis antigen on the CMI responses in a mouse model. On the basis of findings with other fungal agents, we predicted that circulating paracoccidioidal antigen may be inducing suppressor cells which modulate the CMI response. In this study, we show (i) that a soluble P. brasiliensis culture filtrate antigen (Pb.Ag) emulsified in complete Freund adjuvant and injected subcutaneously into mice induces reasonably high levels of delayed-type hypersensitivity (DTH) in CBA/J mice; (ii) that Pb.Ag elicits DTH reactions specific for P. brasiliensis when injected into footpads of immunized mice; and (iii) that an intravenous injection of Pb.Ag induces a population of lymph node and spleen cells which, upon adoptive transfer, suppress the afferent limb of the DTH response to paracoccidioidal antigen. The afferent suppressor cells can be detected in spleens as early as 5 days after Pb.Ag treatment, are present in significant numbers by 7 days in both spleens and lymph nodes, and are virtually absent by 14 days. In contrast, at 14 days after antigen injection, efferent suppressor cells were detected in spleens and lymph nodes. The Pb.Ag-induced afferent suppressor cells specifically inhibit the antiparacoccidioidal DTH response. They are nylon wool-nonadherent cells, and their activity is abrogated by anti-Thy-1 and complement treatment, indicating that they are T lymphocytes. The phenotype of these afferent suppressor T cells is L3T4+ Lyt-1+2- I-J+. The Pb.Ag-specific suppressor cells described in this paper are similar to the Ts1 cells in the azobenzenearsonate, 4-hydroxy-3-nitrophenyl acetyl, and cryptococcal models of suppression of the DTH response and to the afferent suppressor cells in the dinitrofluorobenzene contact sensitivity system. Images PMID:2964411

  14. Paracoccidioides brasiliensis and P. lutzii antigens elicit different serum IgG responses in chronic paracoccidioidomycosis.

    PubMed

    Lenhard-Vidal, A; Assolini, J P; Ono, M A; Bredt, C S O; Sano, A; Itano, E N

    2013-12-01

    Paracoccidioidomycosis (PCM) is a systemic mycosis caused by the fungus Paracoccidioides brasiliensis (S1, PS2, and PS3) and by the new species, P. lutzii. Considering that genetic differences in the Paracoccidioides genus could elicit distinct immune responses by the host, current research investigated serum IgG levels to antigens from P. brasiliensis B339 (S1), P. brasiliensis LDR3 (PS2), and atypical strain LDR2 (P. lutzii), in patients with chronic PCM from the northern and west regions of Paraná, Brazil (n = 35). Cell-free antigen (CFA) and high molecular mass fraction (hMM) were produced from each strain. Samples were analyzed by ELISA and immunodiffusion (ID). ELISA positivity using CFA: B339-100 %, LDR3-83 %, and LDR2-74 %. Response to CFA from B339 was more intense (p < 0.05), while there was no difference between LDR3-LDR2. IgG anti-hMM was higher for antigens from B339 or LDR3, when compared with LDR2 (p < 0.05). There was a positive correlation for each strain between CFA-hMM and for hMM between B339-LDR3 and LDR3-LDR2. ID positivity with CFA: B339-63 %, LDR3-66 %, and LDR2-60 %. We conclude that the intensity of reaction of the patients' sera varies with the strain used; hMM influences tests that use CFA, independently of strain; using ID, positive rates were very similar, but there was a large number of false negative results; ELISA tests using antigens from P. brasiliensis S1 were able to detect a larger number of patients than PS2 and P. lutzii (which had a considerable number of false negative results), and therefore, its use may be more appropriate in this region of Brazil. PMID:24005606

  15. Inhibition of PbGP43 Expression May Suggest that gp43 is a Virulence Factor in Paracoccidioides brasiliensis

    PubMed Central

    Torres, Isaura; Hernandez, Orville; Tamayo, Diana; Muñoz, Jose F.; Leitão, Natanael P.; García, Ana M.; Restrepo, Angela

    2013-01-01

    Glycoprotein gp43 is an immunodominant diagnostic antigen for paracoccidioidomycosis caused by Paracoccidioides brasiliensis. It is abundantly secreted in isolates such as Pb339. It is structurally related to beta-1,3-exoglucanases, however inactive. Its function in fungal biology is unknown, but it elicits humoral, innate and protective cellular immune responses; it binds to extracellular matrix-associated proteins. In this study we applied an antisense RNA (aRNA) technology and Agrobacterium tumefaciens-mediated transformation to generate mitotically stable PbGP43 mutants (PbGP43 aRNA) derived from wild type Pb339 to study its role in P. brasiliensis biology and during infection. Control PbEV was transformed with empty vector. Growth curve, cell vitality and morphology of PbGP43 aRNA mutants were indistinguishable from those of controls. PbGP43 expression was reduced 80–85% in mutants 1 and 2, as determined by real time PCR, correlating with a massive decrease in gp43 expression. This was shown by immunoblotting of culture supernatants revealed with anti-gp43 mouse monoclonal and rabbit polyclonal antibodies, and also by affinity-ligand assays of extracellular molecules with laminin and fibronectin. In vitro, there was significantly increased TNF-? production and reduced yeast recovery when PbGP43 aRNA1 was exposed to IFN-?-stimulated macrophages, suggesting reduced binding/uptake and/or increased killing. In vivo, fungal burden in lungs of BALB/c mice infected with silenced mutant was negligible and associated with decreased lung ???10 and IL-6. Therefore, our results correlated low gp43 expression with lower pathogenicity in mice, but that will be definitely proven when PbGP43 knockouts become available. This is the first study of gp43 using genetically modified P. brasiliensis. PMID:23874627

  16. Molecular detection of Paracoccidioides brasiliensis in road-killed wild animals.

    PubMed

    Richini-Pereira, Virgínia Bodelão; Bosco, Sandra de Moraes Gimenes; Griese, Juliana; Theodoro, Raquel Cordeiro; Macoris, Severino Assis Graça; da Silva, Reinaldo José; Barrozo, Lígia; Tavares, Patrícia Morais e Silva; Zancopé-Oliveira, Rosely Maria; Bagagli, Eduardo

    2008-02-01

    Paracoccidioides brasiliensis infections have been little studied in wild and/or domestic animals, which may represent an important indicator of the presence of the pathogen in nature. Road-killed wild animals have been used for surveillance of vectors of zoonotic pathogens and may offer new opportunities for eco-epidemiological studies of paracoccidiodomycosis (PCM). The presence of P. brasiliensis infection was evaluated by Nested-PCR in tissue samples collected from 19 road-killed animals; 3 Cavia aperea (guinea pig), 5 Cerdocyon thous (crab-eating-fox), 1 Dasypus novemcinctus (nine-banded armadillo), 1 Dasypus septemcinctus (seven-banded armadillo), 2 Didelphis albiventris (white-eared opossum), 1 Eira barbara (tayra), 2 Gallictis vittata (grison), 2 Procyon cancrivorus (raccoon) and 2 Sphiggurus spinosus (porcupine). Specific P. brasiliensis amplicons were detected in (a) several organs of the two armadillos and one guinea pig, (b) the lung and liver of the porcupine, and (c) the lungs of raccoons and grisons. P. brasiliensis infection in wild animals from endemic areas might be more common than initially postulated. Molecular techniques can be used for detecting new hosts and mapping 'hot spot' areas of PCM. PMID:17885959

  17. Ecological study of Paracoccidioides brasiliensis in soil: growth ability, conidia production and molecular detection

    PubMed Central

    Terçarioli, Gisela Ramos; Bagagli, Eduardo; Reis, Gabriela Martins; Theodoro, Raquel Cordeiro; Bosco, Sandra De Moraes Gimenes; Macoris, Severino Assis da Graça; Richini-Pereira, Virgínia Bodelão

    2007-01-01

    Background Paracoccidioides brasiliensis ecology is not completely understood, although several pieces of evidence point to the soil as its most probable habitat. The present study aimed to investigate the fungal growth, conidia production and molecular pathogen detection in different soil conditions. Methods Soils samples of clayey, sandy and medium textures were collected from ground surface and the interior of armadillo burrows in a hyperendemic area of Paracoccidioidomycosis. P. brasiliensis was inoculated in soil with controlled humidity and in culture medium containing soil extracts. The molecular detection was carried out by Nested PCR, using panfungal and species specific primers from the ITS-5.8S rDNA region. Results The soil texture does not affect fungus development and the growth is more abundant on/in soil saturated with water. Some soil samples inhibited the development of P. brasiliensis, especially those that contain high values of Exchangeable Aluminum (H+Al) in their composition. Some isolates produced a large number of conidia, mainly in soil-extract agar medium. The molecular detection was positive only in samples collected from armadillo burrows, both in sandy and clayey soil. Conclusion P. brasiliensis may grow and produce the infectious conidia in sandy and clayey soil, containing high water content, mainly in wild animal burrows, but without high values of H+Al. PMID:17953742

  18. Serological Investigation into Paracoccidioides brasiliensis Infection in Dogs from Southern Rio Grande do Sul, Brazil.

    PubMed

    Teles, Alessandra Jacomelli; Klafke, Gabriel Baracy; Cabana, Ângela Leitzke; Albano, Ana Paula Neuschrank; Xavier, Melissa Orzechowski; Meireles, Mário Carlos Araújo

    2016-04-01

    Paracoccidioides brasiliensis is a dimorphic fungus and major cause of paracoccidioidomycosis (PCM), which is a systemic and endemic mycosis in Brazil. In Southern Brazil, an increased number of cases were detected since the 1990 s. Therefore, in order to determine areas with the presence of the fungus, this study aimed to investigate infection by P. brasiliensis in dogs from Southern Brazil. Indirect ELISA was used to detect antibodies against P. brasiliensis gp43. One hundred and ninety-six stray and semi-domiciled dogs from the municipalities of Pelotas and Capão do Leão, Rio Grande do Sul were included in this study. P. brasiliensis infection was detected in 58 animals (29.6 %) with no significant difference for gender, age and breed. Seropositive animals were detected in all neighborhoods in the city of Pelotas as well as in the neighboring municipality Capão do Leão. The detection of antibodies against gp43 in dogs suggests the presence and wide distribution of the fungus in Pelotas and Capão do Leão, warning for the possibility of PCM disease in dogs as well as in humans from this region. PMID:26608381

  19. Activation of the alternative complement pathway in canine normal serum by Paracoccidioides brasiliensis

    PubMed Central

    Bianchini, A.A.C.; Petroni, T.F.; Fedatto, P.F.; Bianchini, R.R.; Venancio, E.J.; Itano, E.N.; Ono, M.A.

    2009-01-01

    The dimorphic fungus Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, a human granulomatous disease. Recently the first case of natural disease in dogs was reported. The complement system is an important effector component of humoral immunity against infectious agents. Therefore, the aim of this study was to evaluate the activation of the dog alternative complement pathway by P. brasiliensis. Initially, the ability of erythrocytes of guinea pig, rabbit, sheep, chicken and swine to activate the dog alternative pathway was evaluated. The guinea pig erythrocytes showed the greatest capacity to activate dog alternative pathway. The alternative (AH50) hemolytic activity was evaluated in 27 serum samples from healthy dogs and the mean values were 87.2 AH50/ml. No significant differences were observed in relation to sex and age. The alternative pathway activation by P. brasiliensis was higher in serum samples from adult dogs when compared to puppies and aged dogs (p ? 0.05). This is the first report of dog alternative complement pathway activation by P. brasiliensis and suggests that it may play a protective role in canine paracoccidioidomycosis. PMID:24031350

  20. Isolation of Paracoccidioides brasiliensis from armadillos (Dasypus noveminctus) captured in an endemic area of paracoccidioidomycosis.

    PubMed

    Bagagli, E; Sano, A; Coelho, K I; Alquati, S; Miyaji, M; de Camargo, Z P; Gomes, G M; Franco, M; Montenegro, M R

    1998-04-01

    Paracoccidioides brasiliensis, the causative agent of paracoccidioidomycosis (PCM), was first isolated from armadillos from the Amazonian region where the mycosis is uncommon. In the present study, we report on the high incidence of PCM infection in armadillos from a hyperendemic region of the disease. Four nine-banded armadillos (Dasypus novemcinctus) were captured in the endemic area of Botucatu, Sao Paulo, Brazil, killed by manual cervical dislocation and autopsied under sterile conditions. Fragments of lung, spleen, liver, and mesenteric lymph nodes were processed for histology, cultured on Mycosel agar at 37 degrees C, and homogenized for inoculation into the testis and peritoneum of hamsters. The animals were killed from week 6 to week 20 postinoculation and fragments of liver, lung, spleen, testis, and lymph nodes were cultured on brain heart infusion agar at 37 degrees C. Paracoccidioides brasiliensis was isolated from three armadillos both by direct organ culture and from the liver, spleen, lung, and mesenteric lymph nodes of hamsters. In addition, one positive armadillo presented histologically proven PCM disease in a mesenteric lymph node. The three armadillos isolates (Pb-A1, Pb-A2, and Pb-A4) presented thermodependent dimorphism, urease activity, and casein assimilation, showed amplification of the gp43 gene, and were highly virulent in intratesticularly inoculated hamsters. The isolates expressed the gp43 glycoprotein, the immunodominant antigen of the fungus, and reacted with a pool of sera from PCM patients. Taken together, the present data confirm that armadillos are a natural reservoir of P. brasiliensis and demonstrate that the animal is a sylvan host to the fungus. PMID:9574800

  1. Immunohistochemical detection of a novel 22- to 25-kilodalton glycoprotein of Paracoccidioides brasiliensis in biopsy material and partial characterization by using species-specific monoclonal antibodies.

    PubMed Central

    Figueroa, J I; Hamilton, A; Allen, M; Hay, R

    1994-01-01

    Two murine monoclonal antibodies (MAbs) specific to Paracoccidioides brasiliensis (as determined by enzyme-linked immunosorbent assay [ELISA] and Western blot [immunoblot]) were produced by using a modification of standard hybridization protocols, with cyclophosphamide included as an immunomodulator to abolish responses to highly cross-reactive immunodominant epitopes. MAbs PS14 and PS15 are two different clones which exhibit similar characteristics by ELISA and Western blot. They are directed against a 22- to 25-kDa antigen which is present in P. brasiliensis and which could not be identified in other dimorphic fungi by ELISA or Western blot. Partial purification of the antigen was accomplished by isoelectric focusing, and deglycosylation studies suggested that the 22- to 25-kDa antigen is a glycoprotein with a pI of between 4.5 and 5 and that O-linked sugars may be part of the recognized epitope. The MAbs stained the cytoplasm of P. brasiliensis yeast and hyphal cells in cryostat sections of fresh cultures of the fungus. In addition, the MAbs stained the wall of paracoccidioidomycotic granulomas, as well as the cytoplasm of the fungus, as determined by the use of immunofluorescence, immunoperoxidase, and immuno-alkaline phosphatase staining techniques in paraffin-embedded sections of human biopsy material, and they failed to stain granulomas resulting from other clinical conditions. These findings suggest that these MAbs have potential use in the immunohistochemical identification of P. brasiliensis. Images PMID:8077405

  2. Rapid and reliable method for production of a specific Paracoccidioides brasiliensis immunodiffusion test antigen.

    PubMed Central

    Blumer, S O; Jalbert, M; Kaufman, L

    1984-01-01

    Previously published methods to produce Paracoccidioides brasiliensis antigens for serological tests have yielded antigens of inconsistent quality and have involved the use of special semisynthetic media and growth periods of 1 to 3 months to yield suitable reagents. A simple procedure that uses commercially available potato glucose agar and either SABHI broth (Difco Laboratories) or Trypticase soy broth (BBL Microbiology Systems) inoculated with the mycelial form of P. brasiliensis consistently yielded high-titer antigens in 2 weeks or less. This new method permits the almost exclusive production of an antigen identical to the specific E antigen described by Yarzabal (Yarzabal et al., Sabouradia 14:275-280, 1976) and the apparently equivalent specific antigen 1 described by Restrepo and Moncada (A. Restrepo and L. H. Moncada, Appl. Microbiol. 28:138-144, 1974). In the immunodiffusion test, the rapidly produced antigen demonstrated a sensitivity of 90% by detecting antibody in sera from 103 of 114 proven cases of paracoccidioidomycosis. The specificity of this antigen was 100% because none of 139 sera from patients with heterologous mycotic diseases demonstrated diagnostic precipitins against the P. brasiliensis antigen. In the complement fixation tests, the rapidly produced antigen was not as suitable as the one prepared by the method of Restrepo-Moreno and Schneidau (A. Restrepo-Moreno and J. D. Schneidau, Jr., J. Bacteriol. 93:1741-1748, 1967). Images PMID:6425358

  3. Response of Paracoccidioides brasiliensis Pb01 to stressor agents and cell wall osmoregulators.

    PubMed

    Tomazett, Patrícia Kott; Castro, Nadya da Silva; Lenzi, Henrique Leonel; de Almeida Soares, Célia Maria; Pereira, Maristela

    2011-01-01

    In its attempt to survive, the fungal cell can change the cell wall composition and/or structure in response to environmental stress. The molecules involved in these compensatory mechanisms are a possible target for the development of effective antifungal agents. In the thermodimorphic fungus Paracoccidioides brasiliensis Pb01, the main polymers that compose the cell wall are chitin and glucans. These polymers form a primary barrier that is responsible for the structural integrity and formation of the cell wall. In this study the behaviour of P. brasiliensis was evaluated under incubation with cell wall stressor agents such as Calcofluor White (CFW), Congo Red (CR), Sodium Dodecyl Sulphate (SDS), NaCl, KCl, and Sorbitol. Use of concentrations at which the fungus is visually sensitive to those agents helped to explain some of the adaptive mechanisms used by P. brasiliensis in response to cell wall stress. Our results show that 1,3-?-D-glucan synthase (PbFKS1), glucosamine-6-phosphate synthase (PbGFA1) and ?-1,3-glucanosyltransferase (PbGEL3)as well as 1,3-?-D-glucan and N-acetylglucosamine (GlcNAc) residues in the cell wall are involved in compensatory mechanisms against cell wall damage. PMID:21215956

  4. Recombinant Paracoccin Reproduces the Biological Properties of the Native Protein and Induces Protective Th1 Immunity against Paracoccidioides brasiliensis Infection

    PubMed Central

    Alegre, Ana Claudia Paiva; Oliveira, Aline Ferreira; Dos Reis Almeida, Fausto Bruno; Roque-Barreira, Maria Cristina; Hanna, Ebert Seixas

    2014-01-01

    Background Paracoccin is a dual-function protein of the yeast Paracoccidioides brasiliensis that has lectin properties and N-acetylglucosaminidase activities. Proteomic analysis of a paracoccin preparation from P. brasiliensis revealed that the sequence matched that of the hypothetical protein encoded by PADG-3347 of isolate Pb-18, with a polypeptide sequence similar to the family 18 endochitinases. These endochitinases are multi-functional proteins, with distinct lectin and enzymatic domains. Methodology/principal findings The multi-exon assembly and the largest exon of the predicted ORF (PADG-3347), was cloned and expressed in Escherichia coli cells, and the features of the recombinant proteins were compared to those of the native paracoccin. The multi-exon protein was also used for protection assays in a mouse model of paracoccidioidomycosis. Conclusions/Significance Our results showed that the recombinant protein reproduced the biological properties described for the native protein—including binding to laminin in a manner that is dependent on carbohydrate recognition—showed N-acetylglucosaminidase activity, and stimulated murine peritoneal macrophages to produce high levels of TNF-α and nitric oxide. Considering the immunomodulatory potential of glycan-binding proteins, we also investigated whether prophylactic administration of recombinant paracoccin affected the course of experimental paracoccidioidomycosis in mice. In comparison to animals injected with vehicle (controls), mice treated with recombinant paracoccin displayed lower pulmonary fungal burdens and reduced pulmonary granulomas. These protective effects were associated with augmented pulmonary levels of IL-12 and IFN-γ. We also observed that injection of paracoccin three days before challenge was the most efficient administration protocol, as the induced Th1 immunity was balanced by high levels of pulmonary IL-10, which may prevent the tissue damage caused by exacerbated inflammation. The results indicated that paracoccin is the protein encoded by PADG-3347, and we propose that this gene and homologous proteins in other P. brasiliensis strains be called paracoccin. We also concluded that recombinant paracoccin confers resistance to murine P. brasiliensis infection by exerting immunomodulatory effects. PMID:24743161

  5. Paracoccidioides brasiliensis 87-Kilodalton Antigen, a Heat Shock Protein Useful in Diagnosis: Characterization, Purification, and Detection in Biopsy Material via Immunohistochemistry

    PubMed Central

    Díez, Soraya; Gómez, Beatriz L.; Restrepo, Angela; Hay, Rod J.; Hamilton, Andrew J.

    2002-01-01

    The 87-kDa antigen derived from the fungal pathogen Paracoccidioides brasiliensis can be detected in the sera of infected patients, and its levels have been shown to correlate well with response to treatment and with clinical cure. Despite its potential importance, the antigen has been poorly characterized. The 87-kDa antigen was purified to homogeneity via preparative gel electrophoresis; N-terminal amino acid sequencing revealed substantial homology with heat shock proteins (hsps) from a variety of organisms. A monoclonal antibody (MAb) raised against a Histoplasma capsulatum 80-kDa hsp showed cross-reactivity to the purified 87-kDa antigen via Western blotting, and the 87-kDa-specific MAb P1B demonstrated that the antigen was expressed at higher levels in yeast than in mycelia by the same technique. Enzyme-linked immunosorbent assay and immunofluorescence reactivity using P1B confirmed increased expression of the 87-kDa antigen during the temperature-induced transformation of mycelia to yeast. Yeast-to-mycelium transformation was accompanied by a fall in expression, although the 87-kDa antigen was clearly constitutively expressed in both phases. Immunochemical staining of tissues from patients with MAb P1B who were infected with P. brasiliensis confirmed in vivo expression of the 87-kDa antigen by yeasts, and identification of this antigen via this method appears to be a useful adjunct to other methods used to diagnose paracoccidioidomycosis. PMID:11825942

  6. Vaccination with Heat Shock Protein 60 Induces a Protective Immune Response against Experimental Paracoccidioides brasiliensis Pulmonary Infection?

    PubMed Central

    de Bastos Ascenço Soares, Renata; Gomez, Francisco J.; de Almeida Soares, Célia Maria; Deepe, George S.

    2008-01-01

    Paracoccidioides brasiliensis causes a chronic granulomatous mycosis prevalent in Latin America. The successful resolution of infection with this fungus is dependent on the activation of cellular immunity. We previously identified heat shock protein 60 (HSP60) as a target of the humoral response in paracoccidioidomycosis. Herein we expressed the gene encoding HSP60 in Escherichia coli and analyzed the immunological activity of this recombinant antigen. The immunization of BALB/c mice with recombinant protein emulsified in adjuvant stimulated a cellular immune response. Splenocytes from immunized mice proliferated in response to antigen and released interleukin-12 and gamma interferon (IFN-?). Vaccination with HSP60 reduced the fungal burden in mice given 106 or 107 yeasts and protected mice from a lethal challenge. The efficacy of the vaccination was blunted by the neutralization of IFN-?. CD4+ cells were necessary for the efficacy of the vaccination in both the afferent and efferent phases. Thus, we have demonstrated that this immunodominant antigen is a candidate for the development of a vaccine against this fungus. PMID:18625731

  7. Correlation between Histopathological and FT-Raman Spectroscopy Analysis of the Liver of Swiss Mice Infected with Paracoccidioides brasiliensis

    PubMed Central

    Mansano, Elaine Sciuniti Benites; de Morais, Gutierrez Rodrigues; Moratto, Edilaine Martins; Sato, Francielle; Medina Neto, Antonio; Svidzinski, Terezinha Ines Estivalet; Baesso, Mauro Luciano; Hernandes, Luzmarina

    2014-01-01

    Paracoccidioidomycosis is the most important systemic mycosis in Latin America. The main entrance of the fungus is the airway. It primarily occurs in the lung, but in its disseminated form may affect any organ. The liver is one of the organs afflicted by this disease and its homeostasis may be impaired. The aim of the present study was to evaluate the evolution of paracoccidioidomycosis in the liver of Swiss mice and correlate morphological factors with the expression of gp43 and with physicochemical analysis via FT-Raman of the infected organ. According to colony forming unit (CFU) and granuloma counting, the first and second weeks were the periods when infection was most severe. Tissue response was characterized by the development of organized granulomas and widespread infection, with yeasts located within the macrophages and isolated hepatocytes. The gp43 molecule was distributed throughout the hepatic parenchyma, and immunostaining was constant in all observed periods. The main physicochemical changes of the infected liver were observed in the spectral ranges between 1700–1530 cm?1 and 1370 – 1290 cm?1, a peak shifting center attributed to phenylalanine and area variation of -CH2 and -CH3 compounds associated to collagen, respectively. Over time, there was a direct proportional relationship between the number of CFUs, the number of granulomas and the physicochemical changes in the liver of mice infected with Paracoccidioides brasiliensis. The expression of gp43 was similar in all observed periods. PMID:25181524

  8. Influence of Different Media, Incubation Times, and Temperatures for Determining the MICs of Seven Antifungal Agents against Paracoccidioides brasiliensis by Microdilution

    PubMed Central

    Cruz, R. C.; Werneck, S. M. C.; Oliveira, C. S.; Santos, P. C.; Soares, B. M.; Santos, D. A.

    2013-01-01

    MIC assays with Paracoccidioides brasiliensis, the etiological agent of paracoccidioidomycosis, had been conducted with variable protocols, employing both macrodilution and microdilution tests and including differences in inoculum preparation, media used, incubation periods, and temperatures. Twenty-one clinical and environmental isolates of Paracoccidioides were tested using amphotericin B, itraconazole, ketoconazole, fluconazole, sulfamethoxazole, sulfamethoxazole-trimethoprim, and terbinafine, according to the National Committee for Clinical Laboratory Standards (National Committee for Clinical Laboratory Standards, document M27-A2, 2002), with modifications such as three medium formulations (RPMI 1640 medium, McVeigh and Morton [MVM] medium, and modified Mueller-Hinton [MMH] medium), two incubation temperatures (room temperature [25 to 28°C] and 37°C), and three incubation periods (7, 10, and 15 days). The antifungal activities were also classified as fungicidal or fungistatic. The best results were obtained after 15 days of incubation, which was chosen as the standard incubation time. The MICs for most individual isolates grown for the same length of time at the same temperature varied with the different media used (P < 0.05). Of the isolates, 81% showed transition from the yeast to the mycelial form in RPMI 1640 medium at 37°C, independent of the presence of antifungals. MMH medium appears to be a suitable medium for susceptibility testing of antifungal drugs with P. brasiliensis, except for sulfamethoxazole and the combination of sulfamethoxazole-trimethoprim, for which the MVM medium yielded better results. The incubation temperature influenced the MICs, with, in general, higher MICs at 25°C (mycelial form) than at 37°C (P < 0.05). Based on our results, we tentatively propose a microdilution assay protocol for susceptibility testing of antifungal drugs against Paracoccidioides. PMID:23175254

  9. High frequency of Paracoccidioides brasiliensis infection in armadillos (Dasypus novemcinctus): an ecological study.

    PubMed

    Bagagli, E; Franco, M; Bosco, S De M G; Hebeler-Barbosa, F; Trinca, L A; Montenegro, M R

    2003-06-01

    The fungus Paracoccidioides brasiliensis has been isolated from nine-banded armadillos (Dasypus novemcinctus) in different regions where paracoccidiodomycosis (PCM) is endemic. The link between PCM and these animals has provided the first valuable clue in the effort to elucidate the ecological niche of P. brasiliensis. The present study was aimed at correlating P. brasiliensis infection in armadillos with local ecological features and, if possible, the presence of the fungus in the soil in the Botucatu hyperendemic area of PCM. In this region the mean temperature ranges from 14.8 to 25.8 degrees C and the annual average precipitation is 1520 mm. The sites where 10 infected animals (positive group) were collected were studied and compared with the sites where five uninfected animals were found. The occurrence of the fungus in soil samples collected from the positive armadillos' burrows and foraging sites was investigated by the indirect method of animal inoculation. Environmental data from the sites of animal capture, such as temperature, rainfall, altitude, vegetation, soil composition, presence of water and proximity of urban areas, were recorded. All 37 soil samples collected from the sites had negative fungal cultures. Positive animals were found much more frequently in sites with disturbed vegetation, such as riparian forests and artificial Eucalyptus or Pinus forests, in altitudes below 800 m, near water sources. The soil type of the sites of positive animals was mainly sandy, with medium to low concentrations of organic matter. The pH was mainly acidic at all the sites, although the concentrations of aluminum cations (H+Al) were lower at the sites where positive animals were found. Positive armadillos were also captured in sites very close to urban areas. Our data and previous studies indicate that P. brasiliensis occurs preferentially in humid and shady disturbed forests in a strong association with armadillos. PMID:12964713

  10. Importance of xenarthrans in the eco-epidemiology of Paracoccidioides brasiliensis

    PubMed Central

    2009-01-01

    Background Several pathogens that cause important zoonotic diseases have been frequently associated with armadillos and other xenarthrans. This mammal group typically has evolved on the South American continent and many of its extant species are seriously threatened with extinction. Natural infection of armadillos with Paracoccidioides brasiliensis in hyperendemic areas has provided a valuable opportunity for understanding the role of this mammal in the eco-epidemiology of Paracoccidioidomycosis (PCM), one of the most important systemic mycoses in Latin America. Findings This study aimed to detect P. brasiliensis in different xenarthran species (Dasypus novemcinctus, Cabassous spp., Euphractus sexcinctus, Tamandua tetradactyla and Myrmecophaga tridactyla), by molecular and mycological approaches, in samples obtained by one of the following strategies: i) from road-killed animals (n = 6); ii) from naturally dead animals (n = 8); iii) from animals that died in captivity (n = 9); and iv) from living animals captured from the wild (n = 2). Specific P. brasiliensis DNA was detected in several organs among 7/20 nine-banded armadillos (D. novemcinctus) and in 2/2 anteaters (M. tridactyla). The fungus was also cultured in tissue samples from one of two armadillos captured from the wild. Conclusion Members of the Xenarthra Order, especially armadillos, have some characteristics, including a weak cellular immune response and low body temperature, which make them suitable models for studying host-pathogen interaction. P. brasiliensis infection in wild animals, from PCM endemic areas, may be more common than initially postulated and reinforces the use of these animals as sentinels for the pathogen in the environment. PMID:19919716

  11. Experimental infections with Paracoccidioides brasiliensis obtained from armadillos: comparison to clinical isolates.

    PubMed

    Nishikaku, Angela Satie; Peraçoli, Maria Terezinha S; Bagagli, Eduardo; Sugizaki, Maria Fátima; Sartori, Alexandrina

    2008-02-01

    Paracoccidioides brasiliensis causes paracoccidioidomycosis (PCM) that is one of the most prevalent systemic human mycoses in Latin America. Armadillos show a high incidence of PCM infection and could, therefore, be a natural reservoir for this fungus. In this study were compared the virulence profiles of isolates obtained from nine-banded armadillos (Dasypus novemcinctus) (PbT1 and PbT4) and isolates from PCM patients (Pb265 and Bt83). Pathogenicity was evaluated by fungal load and analysis of colony morphology. Immunity against the fungus was tested by delayed type hypersensitivity test (DTH) and antibody quantification by ELISA. The higher virulence of PbT1 and PbT4 was suggested by higher fungal load in spleen and lungs. Armadillo isolates and Bt83 presented a cotton-like surface contrasting with the cerebriform appearance of Pb265. All isolates induced cellular and humoral immune responses in infected BALB/c mice. DTH reactions were similarly induced by the four isolates, however, a great variability was observed in specific antibody levels, being the highest ones induced by Bt83 and PbT4. The present work confirms that armadillos harbor P. brasiliensis, whose multiplication and induced immunity in experimentally infected mice are heterogeneous, resembling the behavior of isolates from human PCM. This study reinforces the possibility that armadillos play an important role in the biological cycle of this pathogen. PMID:18553016

  12. Monoclonal antibody capture enzyme immunoassay for detection of Paracoccidioides brasiliensis antibodies in paracoccidioidomycosis.

    PubMed Central

    Camargo, Z P; Gesztesi, J L; Saraiva, E C; Taborda, C P; Vicentini, A P; Lopes, J D

    1994-01-01

    Four murine monoclonal antibodies (MAbs 17C, 21A, 21F, and 32B) raised against the 43-kDa glycoprotein of Paracoccidioides brasiliensis were tested in a capture enzyme immunoassay (EIA) for the detection of specific human anti-gp43 immunoglobulin G in patients with paracoccidioidomycosis (PCM). All MAbs reacted similarly in the assay. These MAbs, which detected anti-gp43 at levels of as low as 500 pg/ml, were demonstrated to specifically recognize at least two different epitopes in gp43 binding assays. Specific antibodies in the sera of patients with active PCM were detected at dilutions of as high as 1:819,200, and the reactivities of patient sera, as measured by optical densities, were found to be significantly higher than those of control sera. The comparison between classical ELISA and our capture enzyme immunoassay showed that both sensitivity and specificity were greatly improved by the latter. These MAbs represent the first specific reagents to P. brasiliensis described for use in serological tests for PCM. Images PMID:7814469

  13. Geographic Discrimination of Paracoccidioides brasiliensis Strains by Randomly Amplified Polymorphic DNA Analysis

    PubMed Central

    Calcagno, Ana María; Niño-Vega, Gustavo; San-Blas, Felipe; San-Blas, Gioconda

    1998-01-01

    Randomly amplified polymorphic DNA (RAPD) analysis of 33 Paracoccidioides brasiliensis strains from Argentina, Brazil, Colombia, Peru, and Venezuela produced reproducible amplification products which were sufficiently polymorphic to allow differentiation of the strains. Types generated with five primers (OPG 03, OPG 05, OPG 14, OPG 16, and OPG 18) resulted in a high discriminatory index (0.956). The discriminatory index was slightly reduced (0.940) when only two primers (OPG 3 and OPG 14) were used. A dendrogram based on these results showed a high degree of similarity among the strains, and genetic differences were expressed in clusters related to geographical regions but not to pathological features of the disease. With a few exceptions, strains were sorted into five groups by geographical origin as follows: group I, Venezuelan strains; group II, Brazilian strains; group III, Peruvian strains; group IV, Colombian strains; and group V, Argentinian strains. The group containing the most disparate strains was group V (discriminatory index, 0.633); the discriminatory index for the other four groups was 0.824. The use of primer OPG 18 by itself was sufficient to discriminate species specificity, and the use of primer OPG 14 by itself was sufficient to discriminate among the geographical locations of the strains in the sample. This method may be helpful for epidemiological studies of P. brasiliensis. PMID:9620409

  14. Characterization of an exocellular serine-thiol proteinase activity in Paracoccidioides brasiliensis.

    PubMed Central

    Carmona, A K; Puccia, R; Oliveira, M C; Rodrigues, E G; Juliano, L; Travassos, L R

    1995-01-01

    An exocellular proteinase activity has been characterized in Paracoccidioides brasiliensis culture filtrates. Chromatographic analysis showed that the activity was eluted from an anion-exchange Resource Q column at 0.08-0.1 M NaCl, and by gel filtration near ovalbumin elution, in a single peak. Purification of the proteinase, however, was hampered by the low protein yield, in contrast to the high peptidase activity. Numerous chromogenic peptidyl p-nitroanilide derivatives and internally quenched fluorescent peptides, flanked by Abz (O-aminobenzoyl) and EDDnp (ethylenediaminedinitrophenyl), were tested as substrates. Cleavage was observed with Abz-MKRLTL-EDDnp, Abz-FRLVR-EDDnp, and Abz-PLGLLGR-EDDnp at Leu-Thr, Leu-Val and Leu-Leu/Leu-Gly bonds respectively as determined by isolation of the corresponding fragments by HPLC. Leucine at P1 seemed to be restrictive for the activity of the exocellular enzyme, but threonine (P'1) and leucine (P'2) in Abz-MKRLTL-EDDnp apparently were not essential. Also, a pair of alanines could substitute for lysine (P3) and arginine (P2) in this substrate, with a decrease in the Km values. The exocellular peptidase activity of P. brasiliensis had an optimum pH of > 9.0 and was irreversibly inhibited by PMSF, mercuric acetate and p-hydroxymercuribenzoate. Inhibition of the mercuriate compounds could be partially reversed by Cys/EDTA. E-64 [trans-epoxysuccinyl-L-leucylamido-(4-guanido)butene] was a weak and reversible inhibitor, whereas EDTA and pepstatin were not inhibitory. These results suggest that P. brasiliensis exocellular enzyme belongs to the subfamily of SH-containing serine proteinases. PMID:7619058

  15. Melanin Protects Paracoccidioides brasiliensis from the Effects of Antimicrobial Photodynamic Inhibition and Antifungal Drugs

    PubMed Central

    Baltazar, Ludmila Matos; Werneck, Silvia Maria Cordeiro; Soares, Betânia Maria; Ferreira, Marcus Vinicius L.; Souza, Danielle G.; Pinotti, Marcos; Santos, Daniel Assis

    2015-01-01

    Paracoccidioidomycosis (PCM) is a public health concern in Latin America and South America that when not correctly treated can lead to patient death. In this study, the influence of melanin produced by Paracoccidioides spp. on the effects of treatment with antimicrobial photodynamic inhibition (aPI) and antifungal drugs was evaluated. aPI was performed using toluidine blue (TBO) as a photosensitizer and a 630-nm light-emitting diode (LED) light. The antifungals tested were itraconazole and amphotericin B. We evaluated the effects of each approach, aPI or antifungals, against nonmelanized and melanized yeast cells by performing susceptibility tests and by quantifying oxidative and nitrosative bursts during the experiments. aPI reduced nonmelanized cells by 3.0 log units and melanized cells by 1.3 log units. The results showed that melanization protects the fungal cell, probably by acting as a scavenger of nitric oxide and reactive oxygen species, but not of peroxynitrite. Melanin also increased the MICs of itraconazole and amphotericin B, and the drugs were fungicidal for nonmelanized and fungistatic for melanized yeast cells. Our study shows that melanin production by Paracoccidioides yeast cells serves a protective function during aPI and treatment with itraconazole and amphotericin B. The results suggest that melanin binds to the drugs, changing their antifungal activities, and also acts as a scavenger of reactive oxygen species and nitric oxide, but not of peroxynitrite, indicating that peroxynitrite is the main radical that is responsible for fungal death after aPI. PMID:25896704

  16. Therapeutic Administration of Recombinant Paracoccin Confers Protection against Paracoccidioides brasiliensis Infection: Involvement of TLRs

    PubMed Central

    Alegre-Maller, Ana Claudia Paiva; Mendonça, Flávia Costa; da Silva, Thiago Aparecido; Oliveira, Aline Ferreira; Freitas, Mateus Silveira; Hanna, Ebert Seixas; Almeida, Igor C.; Gay, Nicholas J.; Roque-Barreira, Maria Cristina

    2014-01-01

    Background Paracoccin (PCN) is an N-acetylglucosamine-binding lectin from the human pathogenic fungus Paracoccidioides brasiliensis. Recombinant PCN (rPCN) induces a T helper (Th) 1 immune response when prophylactically administered to BALB/c mice, protecting them against subsequent challenge with P. brasiliensis. In this study, we investigated the therapeutic effect of rPCN in experimental paracoccidioidomycosis (PCM) and the mechanism accounting for its beneficial action. Methodology/Principal Findings Four distinct regimens of rPCN administration were assayed to identify which was the most protective, relative to vehicle administration. In all rPCN-treated mice, pulmonary granulomas were less numerous and more compact. Moreover, fewer colony-forming units were recovered from the lungs of rPCN-treated mice. Although all therapeutic regimens of rPCN were protective, maximal efficacy was obtained with two subcutaneous injections of 0.5 µg rPCN at 3 and 10 days after infection. The rPCN treatment was also associated with higher pulmonary levels of IL-12, IFN-?, TNF-?, nitric oxide (NO), and IL-10, without IL-4 augmentation. Encouraged by the pulmonary cytokine profile of treated mice and by the fact that in vitro rPCN-stimulated macrophages released high levels of IL-12, we investigated the interaction of rPCN with Toll-like receptors (TLRs). Using a reporter assay in transfected HEK293T cells, we verified that rPCN activated TLR2 and TLR4. The activation occurred independently of TLR2 heterodimerization with TLR1 or TLR6 and did not require the presence of the CD14 or CD36 co-receptors. The interaction between rPCN and TLR2 depended on carbohydrate recognition because it was affected by mutation of the receptor's N-glycosylation sites. The fourth TLR2 N-glycan was especially critical for the rPCN-TLR2 interaction. Conclusions/Significance Based on our results, we propose that PCN acts as a TLR agonist. PCN binds to N-glycans on TLRs, triggers regulated Th1 immunity, and exerts a therapeutic effect against P. brasiliensis infection. PMID:25474158

  17. IgM and IgG antibody response to Paracoccidioides brasiliensis in naturally infected wild armadillos (Dasypus novemcinctus).

    PubMed

    Fernandes, G F; Deps, P; Tomimori-Yamashita, J; Camargo, Z P

    2004-08-01

    We studied the extent to which wild nine-banded armadillos, Dasypus novemcinctus, produce immune humoral responses specifically directed against characteristic Paracoccidioides brasiliensis antigens. Such antibody production might reflect direct contact with the ecological microniche of P. brasiliensis, or might merely reflect inhalation of widely distributed airborne propagules. An enzyme-linked immunosorbent assay (ELISA) was designed containing purified glycoprotein gp43 and gp70 antigens from P. brasiliensis as well as cross-reactive antisera originally targeted against human IgM (mu chain) and armadillo anti-IgG (gamma-chain). It was used to detect and classify IgM and IgG antibodies to P. brasiliensis in the armadillo. In a serological survey of 47 wild armadillos, IgM antibodies to gp43 were detected in seven animals (14.8%), and IgG antibodies were detected in 20 (42.5%). IgM antibodies to gp70 were detected in 10 (21.3%) animals and IgG antibodies were detected in 18 (38.3%). These results, showing a pattern consistent with infection, suggest that P. brasiliensis is enzootic in armadillos. How the animals became exposed could not be determined. PMID:15473362

  18. Induction of the synthesis of cell wall alpha-1,3-glucan in the yeastlike form of Paracoccidioides brasiliensis strain IVIC Pb9 by fetal calf serum.

    PubMed Central

    San-Blas, G; Vernet, D

    1977-01-01

    In vitro subculturing of the yeastlike form of Paracoccidioides brasiliensis strain IVIC Pb9 leads to the disappearance of alpha-1,3-glucan as a main component of its cell wall. However, the addition of fetal calf serum to the growth medium induces the synthesis of this polysaccharide. It is suggested that the synthesis of alpha-1,3-glucan in the cell wall of the yeastlike form of P. brasiliensis is induced by external factors. Images PMID:858645

  19. The naked-tailed armadillo Cabassous centralis (Miller 1899): a new host to Paracoccidioides brasiliensis. Molecular identification of the isolate.

    PubMed

    Corredor, Germán G; Peralta, Luis A; Castaño, John H; Zuluaga, Juan S; Henao, Beatriz; Arango, Myrtha; Tabares, Angela M; Matute, Daniel R; McEwen, Juan G; Restrepo, Angela

    2005-05-01

    The natural habitat of Paracoccidioides brasiliensis remains undefined but the repeated demonstration of infection by this fungus in the nine-banded armadillo Dasypus novemcinctus has opened interesting research avenues. We report here the isolation of this fungus from the spleen of a naked-tailed armadillo Cabassous centralis (Miller 1899) captured in a coffee farm localized in the Colombian endemic area for paracoccidioidomycosis. This particular isolate was identified by its dimorphism and also by comparison of the PbGP43 gene and ribosomal internal transcribed spacer regions (ITS) with recognized P brasiliensis strains. This finding extends the range of naturally acquired infections in mammals of the family Dasypodidae and confirms the existence of this human pathogen in areas where human paracoccidioidomycosis is known to occur. PMID:16010854

  20. Comparison of the sequences of the internal transcribed spacer regions and PbGP43 genes of Paracoccidioides brasiliensis from patients and armadillos (Dasypus novemcinctus).

    PubMed

    Hebeler-Barbosa, Flavia; Morais, Flavia V; Montenegro, Mario R; Kuramae, Eiko E; Montes, Beatriz; McEwen, Juan G; Bagagli, Eduardo; Puccia, Rosana

    2003-12-01

    Paracoccidioides brasiliensis isolates from 10 nine-banded armadillos (Dasypus novemcinctus) were comparable with 19 clinical isolates by sequence analysis of the PbGP43 gene and ribosomal internal transcribed spacer 1 (ITS1) and ITS2 and by random amplified polymorphic DNA. In this original ITS study, eight isolates differed by one or three sites among five total substitution sites. PMID:14662970

  1. Use of the 27-Kilodalton Recombinant Protein from Paracoccidioides brasiliensis in Serodiagnosis of Paracoccidioidomycosis

    PubMed Central

    Ortiz, B. L.; Díez, S.; Urán, M. E.; Rivas, J. M.; Romero, M.; Caicedo, V.; Restrepo, A.; McEwen, J. G.

    1998-01-01

    Paracoccidioidomycosis (PCM) is one of the most important endemic mycoses in Latin America; it is usually diagnosed by observation and/or isolation of the etiologic agent, Paracoccidioides brasiliensis, as well as by a variety of immunological methods. Although the latter are effective, two circumstances, cross-reactions with other mycotic agents and antigen preparation that is marked by extreme variability among lots, hinder proper standardization of the procedures. To circumvent this lack of reproducibility, molecular biology tools were used to produce a recombinant 27-kDa-molecular-mass antigen from this fungus; a sizable quantity of this antigen was obtained through fermentation of Escherichia coli DH5α, which is capable of expressing the fungal protein. The latter was purified by the Prep-Cell System (Bio-Rad); the recovery rate of the pure protein was approximately 6%. A battery of 160 human serum samples, consisting of 64 specimens taken at the time of diagnosis from patients with PCM representing the various clinical forms plus 15 serum specimens each from patients with histoplasmosis and aspergillosis, 10 each from patients with cryptococcosis and tuberculosis, 6 from patients with coccidioidomycosis, and 40 from healthy subjects, were all tested by an indirect enzyme-linked immunosorbent assay with the purified 27-kDa recombinant protein. The latter was used at a concentration of 1.0 μg/well; there were three serum dilutions (1:1,000, 1:2,000, and 1:4,000). The experiment was repeated at least twice. The average sensitivity for both experiments was 73.4%; in comparison with the healthy subjects, the specificity for PCM patients was 87.5% while for patients with other mycoses, it was 58.7%. Important cross-reactions with sera from patients with aspergillosis and histoplasmosis were detected. The positive predictive value of the test was 90.4%. These results indicate that it is possible to employ recombinant antigenic proteins for the immunologic diagnosis of PCM and, by so doing, achieve high coverage rates. Furthermore, antigen reproducibility can now be ensured, thus facilitating inter- and intralaboratory standardization. PMID:9801343

  2. Expression and arrangement of extracellular matrix proteins in the lungs of mice infected with Paracoccidioides brasiliensis conidia

    PubMed Central

    González, Angel; Lenzi, Henrique Leonel; Motta, Ester Maria; Caputo, Luzia; Restrepo, Angela; Cano, Luz Elena

    2008-01-01

    Extracellular matrix (ECM) proteins are important modulators of migration, differentiation and proliferation for the various cell types present in the lungs; they influence the immune response as well as participate in the adherence of several fungi including Paracoccidioides brasiliensis. The expression, deposition and arrangement of ECM proteins such as laminin, fibronectin, fibrinogen, collagen and proteoglycans in the lungs of mice infected with P. brasiliensis conidia has been evaluated in this study, together with the elastic fibre system. Lungs of BALB/c mice infected with P. brasiliensis conidia were analysed for the different ECM proteins by histological and immunohistochemical procedures at different times of infection. In addition, laser scanning confocal microscopy and scanning electron microscopy were used. During the early periods, the lungs of infected animals showed an inflammatory infiltrate composed mainly of polymorphonuclear neutrophils (PMNs) and macrophages, while during the later periods, mice presented a chronic inflammatory response with granuloma formation. Re-arrangement and increased expression of all ECM proteins tested were observed throughout all studied periods, especially during the occurrence of inflammatory infiltration and formation of the granuloma. The elastic fibre system showed an elastolysis process in all experiments. In conclusion, this study provides new details of pulmonary ECM distribution during the course of paracoccidioidomycosis. PMID:18336528

  3. Antifungal activity of schinol and a new biphenyl compound isolated from Schinus terebinthifolius against the pathogenic fungus Paracoccidioides brasiliensis

    PubMed Central

    2010-01-01

    Background The aim of this study was to isolate and identify the antifungal compounds from the extracts of Schinus terebinthifolius (Anacardiaceae) against clinical isolates of the pathogenic fungus Paracoccidioides brasiliensis. Methods The hexane and dichlomethane fractions from leaves and stems of S. terebinthifolius were fractionated using several chromatography techniques to afford four compounds. Results The compounds isolated from S. terebinthifolius were identified as schinol (1), a new biphenyl compound, namely, 4'-ethyl-4-methyl-2,2',6,6'-tetrahydroxy[1,1'-biphenyl]-4,4'-dicarboxylate (2), quercetin (3), and kaempferol (4). Compounds 1 and 2 were active against different strains of P. brasiliensis, showing a minimal inhibitory concentration value against the isolate Pb B339 of 15.6 ?g/ml. The isolate Pb 1578 was more sensitive to compound 1 with a MIC value of 7.5 ?g/ml. Schinol presented synergistic effect only when combined with itraconazole. The compounds isolated from S. terebinthifolius were not able to inhibit cell wall synthesis or assembly using the sorbitol assay. Conclusion This work reveals for the first time the occurrence of compound 2 and discloses activity of compounds 1 and 2 against several clinical isolates of P. brasiliensis. These results justify further studies to clarify the mechanisms of action of these compounds. PMID:20939907

  4. Inhibitory effect of deferoxamine or macrophage activation on transformation of Paracoccidioides brasiliensis conidia ingested by macrophages: reversal by holotransferrin.

    PubMed Central

    Cano, L E; Gomez, B; Brummer, E; Restrepo, A; Stevens, D A

    1994-01-01

    Conidia of P. brasiliensis ingested by murine macrophages at 37 degrees C showed enhanced transformation to yeast cells and further intracellular growth compared with conidia in culture medium alone. Treatment of macrophages with the iron chelator deferoxamine inhibited the intracellular conidium-to-yeast transformation. Cytokine-activated macrophages could also exert this inhibitory effect. Holotransferrin reversed the inhibitory effect of either deferoxamine or activated macrophages on intracellular conidium-to-yeast transformation. These results indicate that iron restriction is one of the mechanisms by which activated macrophages control the intracellular transformation of ingested conidia and growth of yeast cells. PMID:8132359

  5. ?-(1,4)-Amylase, but not ?- and ?-(1,3)-glucanases, may be responsible for the impaired growth and morphogenesis of Paracoccidioides brasiliensis induced by N-glycosylation inhibition

    PubMed Central

    Dos Reis Almeida, Fausto Bruno; Pigosso, Laurine Lacerda; de Lima Damásio, André Ricardo; Monteiro, Valdirene Neves; de Almeida Soares, Célia Maria; Silva, Roberto Nascimento; Roque-Barreira, Maria Cristina

    2014-01-01

    The cell wall of Paracoccidioides brasiliensis, which consists of a network of polysaccharides and glycoproteins, is essential for fungal pathogenesis. We have previously reported that N-glycosylation of proteins such as N-acetyl-?-d-glucosaminidase is required for the growth and morphogenesis of P. brasiliensis. In the present study, we investigated the influence of tunycamicin (TM)-mediated inhibition of N-linked glycosylation on ?- and ?-(1,3)-glucanases and on ?-(1,4)-amylase in P. brasiliensis yeast and mycelium cells. The addition of 15 µg/ml TM to the fungal cultures did not interfere with either ?- or ?-(1,3)-glucanase production and secretion. Moreover, incubation with TM did not alter ?- and ?-(1,3)-glucanase activity in yeast and mycelium cell extracts. In contrast, ?-(1,4)-amylase activity was significantly reduced in underglycosylated yeast and mycelium extracts after exposure to TM. In spite of its importance for fungal growth and morphogenesis, N-glycosylation was not required for glucanase activities. This is surprising because these activities are directed to wall components that are crucial for fungal morphogenesis. On the other hand, N-glycans were essential for ?-(1,4)-amylase activity involved in the production of malto-oligosaccharides that act as primer molecules for the biosynthesis of ?-(1,3)-glucan. Our results suggest that reduced fungal ?-(1,4)-amylase activity affects cell wall composition and may account for the impaired growth of underglycosylated yeast and mycelium cells. © 2013 The Authors. Yeast published by John Wiley & Sons Ltd. PMID:24155051

  6. Antifungal activity of extracts of some plants used in Brazilian traditional medicine against the pathogenic fungus Paracoccidioides brasiliensis.

    PubMed

    Johann, Susana; Cisalpino, Patricia Silva; Watanabe, Gisele Almeida; Cota, Betania Barros; de Siqueira, Ezequias Pessoa; Pizzolatti, Moacir Geraldo; Zani, Carlos Leomar; de Resende, Maria Aparecida

    2010-04-01

    Paracoccidioidomycosis (PCM) is a systemic granulomatous disease caused by Paracoccidioides brasiliensis Almeida (Onygenales) that requires 1-2 years of treatment. In the absence of drug therapy, the disease is usually fatal, highlighting the need for the identification of safer, novel, and more effective antifungal compounds. With this need in mind, several plants employed in Brazilian traditional medicine were assayed on P. brasiliensis and murine macrophages. Extracts were prepared from 10 plant species: Inga spp. Mill. (Leguminosae), Schinus terebinthifolius Raddi (Anacardiaceae), Punica granatum L. (Punicaceae), Alternanthera brasiliana Kuntze (Amaranthaceae), Piper regnellii CDC. (Piperaceae), P. abutiloides Kunth (Piperaceae), Herissantia crispa L. Briz. (Malvaceae), Rubus urticaefolius Poir (Rosaceae), Rumex acetosa L. (Polygonaceae), and Baccharis dracunculifolia DC. (Asteraceae). Hexane fractions from hydroalcoholic extracts of Piper regnellii and Baccharis dracunculifolia were the most active against the fungus, displaying minimum inhibitory concentration (MIC) values of 7.8 microg/mL and 7.8-30 mug/mL, respectively. Additionally, neither of the extracts exhibited any apparent cytotoxic effects on murine macrophages at 20 microg/mL. Analyses of these fractions using gas chromatography-mass spectrometry (GC-MS) showed that the major components of B. dracunculifolia were ethyl hydrocinnamate (14.35%) and spathulenol (16.02%), while the major components of the hexane fraction of Piper regnellii were 1-methoxy-4-(1-propenyl) benzene (21.94%) and apiol (21.29%). The activities of these fractions against P. brasiliensis without evidence of cytotoxicity to macrophages justify their investigation as a potential source of new chemical agents for the treatment of PCM. PMID:20645716

  7. Antifungal activity of extracts from Atacama Desert fungi against Paracoccidioides brasiliensis and identification of Aspergillus felis as a promising source of natural bioactive compounds

    PubMed Central

    Mendes, Graziele; Gonçalves, Vívian N; Souza-Fagundes, Elaine M; Kohlhoff, Markus; Rosa, Carlos A; Zani, Carlos L; Cota, Betania B; Rosa, Luiz H; Johann, Susana

    2016-01-01

    Fungi of the genus Paracoccidioides are responsible for paracoccidioidomycosis. The occurrence of drug toxicity and relapse in this disease justify the development of new antifungal agents. Compounds extracted from fungal extract have showing antifungal activity. Extracts of 78 fungi isolated from rocks of the Atacama Desert were tested in a microdilution assay against Paracoccidioides brasiliensis Pb18. Approximately 18% (5) of the extracts showed minimum inhibitory concentration (MIC) values≤ 125.0 µg/mL. Among these, extract from the fungus UFMGCB 8030 demonstrated the best results, with an MIC of 15.6 µg/mL. This isolate was identified as Aspergillus felis (by macro and micromorphologies, and internal transcribed spacer, β-tubulin, and ribosomal polymerase II gene analyses) and was grown in five different culture media and extracted with various solvents to optimise its antifungal activity. Potato dextrose agar culture and dichloromethane extraction resulted in an MIC of 1.9 µg/mL against P. brasiliensis and did not show cytotoxicity at the concentrations tested in normal mammalian cell (Vero). This extract was subjected to bioassay-guided fractionation using analytical C18RP-high-performance liquid chromatography (HPLC) and an antifungal assay using P. brasiliensis. Analysis of the active fractions by HPLC-high resolution mass spectrometry allowed us to identify the antifungal agents present in the A. felis extracts cytochalasins. These results reveal the potential of A. felis as a producer of bioactive compounds with antifungal activity. PMID:27008375

  8. Low-level Laser Therapy to the Mouse Femur Enhances the Fungicidal Response of Neutrophils against Paracoccidioides brasiliensis

    PubMed Central

    Burger, Eva; Mendes, Ana Carolina S. C.; Bani, Giulia M. A. C.; Brigagão, Maísa R. P. L.; Santos, Gérsika B.; Malaquias, Luiz Cosme C.; Chavasco, Jorge Kleber; Verinaud, Liana M.; de Camargo, Zoilo P.; Hamblin, Michael R.; Sperandio, Felipe F.

    2015-01-01

    Neutrophils (PMN) play a central role in host defense against the neglected fungal infection paracoccidioidomycosis (PCM), which is caused by the dimorphic fungus Paracoccidioides brasiliensis (Pb). PCM is of major importance, especially in Latin America, and its treatment relies on the use of antifungal drugs. However, the course of treatment is lengthy, leading to side effects and even development of fungal resistance. The goal of the study was to use low-level laser therapy (LLLT) to stimulate PMN to fight Pb in vivo. Swiss mice with subcutaneous air pouches were inoculated with a virulent strain of Pb or fungal cell wall components (Zymosan), and then received LLLT (780 nm; 50 mW; 12.5 J/cm2; 30 seconds per point, giving a total energy of 0.5 J per point) on alternate days at two points on each hind leg. The aim was to reach the bone marrow in the femur with light. Non-irradiated animals were used as controls. The number and viability of the PMN that migrated to the inoculation site was assessed, as well as their ability to synthesize proteins, produce reactive oxygen species (ROS) and their fungicidal activity. The highly pure PMN populations obtained after 10 days of infection were also subsequently cultured in the presence of Pb for trials of protein production, evaluation of mitochondrial activity, ROS production and quantification of viable fungi growth. PMN from mice that received LLLT were more active metabolically, had higher fungicidal activity against Pb in vivo and also in vitro. The kinetics of neutrophil protein production also correlated with a more activated state. LLLT may be a safe and non-invasive approach to deal with PCM infection. PMID:25675431

  9. Fate of conidia of Paracoccidioides brasiliensis after ingestion by resident macrophages or cytokine-treated macrophages.

    PubMed Central

    Cano, L E; Brummer, E; Stevens, D A; Restrepo, A

    1992-01-01

    Conidia ingested by resident macrophages had an enhanced percentage of transformation to yeast cells compared with those in culture medium without macrophages. The yeast cells subsequently grew intracellularly by budding. Macrophages treated with cytokines from antigen-stimulated spleen cells from immunized mice significantly inhibited transformation of ingested conidia. PMID:1563800

  10. Influence of the Paracoccidioides brasiliensis 14-3-3 and gp43 proteins on the induction of apoptosis in A549 epithelial cells

    PubMed Central

    da Silva, Julhiany de Fátima; Vicentim, Juliana; de Oliveira, Haroldo Cesar; Marcos, Caroline Maria; Assato, Patricia Akemi; Andreotti, Patrícia Ferrari; da Silva, Juliana Leal Monteiro; Soares, Christiane Pienna; Benard, Gil; Almeida, Ana Marisa Fusco; Mendes-Giannini, Maria José Soares

    2015-01-01

    The fungal strain Paracoccidioides brasiliensis remains viable inside of epithelial cells and can induce apoptosis in this population. However, until now, the molecules that participate in this process remained unknown. Thus, this study evaluated the contribution of two P. brasiliensis molecules, the 14-3-3 and glycoprotein of 43 kDa proteins, which had been previously described as extracellular matrix adhesins and apoptosis inductors in human pneumocytes. Accordingly, epithelial cells were treated with these molecules for different periods of time and the expression of the apoptosis regulating-proteins Bak, Bax, Bcl-2, p53 and caspases were evaluated by terminal deoxynucleotidyl transferase dUTP nick end labelling, flow cytometry and real-time polymerase chain reaction analysis. Our results demonstrated that treatment with these molecules induces apoptosis signalling in pulmonary epithelial cells, showing the same pattern of programmed cell-death as that observed during infection with P. brasiliensis. Thus, we could conclude that P. brasiliensis uses these molecules as virulence factors that participate not only in the fungal adhesion process to host cells, but also in other important cellular mechanisms such as apoptosis. PMID:26038961

  11. Structural and Topographic Dynamics of Pulmonary Histopathology and Local Cytokine Profiles in Paracoccidioides brasiliensis Conidia-Infected Mice

    PubMed Central

    Cruz, Oswaldo G.; Restrepo, Angela; Cano, Luz Elena; Lenzi, Henrique Leonel

    2011-01-01

    Background Paracoccidioidomycosis (PCM), an endemic systemic mycosis caused by the fungus Paracoccidioides brasiliensis (Pb), usually results in severe lung damage in patients. Methods and Findings Considering the difficulties to sequentially study the infection in humans, this work was done in mice inoculated intranasally with infective Pb-conidia. Lungs of control and Pb-infected mice were studied after 2-hours, 4, 8, 12 and 16-weeks post-infection (p.i) in order to define histopathologic patterns of pulmonary lesions, multiplex-cytokine profiles and their dynamics during the course of this mycosis. Besides the nodular/granulomatous lesions previously informed, results revealed additional non-formerly described lung abnormalities, such as periarterial sheath inflammation and pseudotumoral masses. The following chronologic stages occurring during the course of the experimental infection were defined: Stage one (2-hours p.i): mild septal infiltration composed by neutrophils and macrophages accompanied by an intense “cytokine burst” represented by significant increases in IL-1?, IL-1?, IL-4, IL-5, IL-6, IL-10, IL12p70, IL-13, IL-17, Eotaxin, G-CSF, MCP1, MIP1?, GM-CSF, IFN-?, MIP1? and TNF? levels. Stage two (4-weeks p.i): presence of nodules, evidence of incipient periarterial- and intense but disperse parenchymal- inflammation, abnormalities that continued to be accompanied by hyper-secretion of those cytokines and chemokines mentioned in the first stage of infection. Stages three and four (8 and 12-weeks p.i.): fungal proliferation, inflammation and collagenesis reached their highest intensity with particular involvement of the periarterial space. Paradoxically, lung cytokines and chemokines were down-regulated with significant decreases in IL-2,IL-3,IL-5,IL-9,IL-13,IL-15,GM-CSF,IFN-?,MIP1? and TNF?. Stage five (16-weeks p.i.): inflammation decreased becoming limited to the pseudotumoral masses and was accompanied by a “silent” cytokine response, except for PDGF, MIG, RANTES and IL12p40 which remained up-regulated for the duration of the experiment. Conclusions Results of this study identified both classic and novel patterns corresponding to histopathologic and immunologic responses occurring during the course of experimental PCM. PMID:21765962

  12. The PbMDJ1 Gene Belongs to a Conserved MDJ1/LON Locus in Thermodimorphic Pathogenic Fungi and Encodes a Heat Shock Protein That Localizes to both the Mitochondria and Cell Wall of Paracoccidioides brasiliensis

    PubMed Central

    Batista, Wagner L.; Matsuo, Alisson L.; Ganiko, Luciane; Barros, Tânia F.; Veiga, Thiago R.; Freymüller, Edna; Puccia, Rosana

    2006-01-01

    J-domain (DnaJ) proteins, of the Hsp40 family, are essential cofactors of their cognate Hsp70 chaperones, besides acting as independent chaperones. In the present study, we have demonstrated the presence of Mdj1, a mitochondrial DnaJ member, not only in the mitochondria, where it is apparently sorted, but also in the cell wall of Paracoccidioides brasiliensis, a thermodimorphic pathogenic fungus. The molecule (PbMdj1) was localized to fungal yeast cells using both confocal and electron microscopy and also flow cytometry. The anti-recombinant PbMdj1 antibodies used in the reactions specifically recognized a single 55-kDa mitochondrial and cell wall (alkaline ?-mercaptoethanol extract) component, compatible with the predicted size of the protein devoid of its matrix peptide-targeting signal. Labeling was abundant throughout the cell wall and especially in the budding regions; however, anti-PbMdj1 did not affect fungal growth in the concentrations tested in vitro, possibly due to the poor access of the antibodies to their target in growing cells. Labeled mitochondria stood preferentially close to the plasma membrane, and gold particles were detected in the thin space between them, toward the cell surface. We show that Mdj1 and the mitochondrial proteinase Lon homologues are heat shock proteins in P. brasiliensis and that their gene organizations are conserved among thermodimorphic fungi and Aspergillus, where the genes are adjacent and have a common 5? region. This is the first time a DnaJ member has been observed on the cell surface, where its function is speculative. PMID:16467478

  13. Phylogenetic and evolutionary aspects of Paracoccidioides brasiliensis reveal a long coexistence with animal hosts that explain several biological features of the pathogen.

    PubMed

    Bagagli, Eduardo; Bosco, Sandra M G; Theodoro, Raquel Cordeiro; Franco, Marcello

    2006-09-01

    The habitat of the mycelial saprobic form of Paracoccidioides brasiliensis, which produces the infectious propagula, has not been determined and has proven difficult for mycologists to describe. The fungus has been rarely isolated from the environment, the disease has a prolonged latency period and no outbreaks have been reported. These facts have precluded the adoption of preventive measures to avoid infection. The confirmation of natural infections in nine-banded armadillos (Dasypus novemcinctus) with P. brasiliensis, in high frequency and wide geographic distribution, has opened new avenues for the study and understanding of its ecology. Armadillos belong to the order Xenarthra, which has existed in South America ever since the Paleocene Era (65 million years ago), when the South American subcontinent was still a detached land, before the consolidation of what is now known as the American continent. On the other hand, strong molecular evidence suggests that P. brasiliensis and other dimorphic pathogenic fungi--such as Blastomyces dermatitidis, Coccidioides immitis and Histoplasma capsulatum--belong to the family Onygenaceae sensu lato (order Onygenales, Ascomycota), which appeared around 150 million years ago. P. brasiliensis ecology and relation to its human host are probably linked to the fungal evolutionary past, especially its long coexistence with and adaptation to animal hosts other than Homo sapiens, of earlier origin. Instead of being a blind alley, the meaning of parasitism for dimorphic pathogenic fungi should be considered as an open two-way avenue, in which the fungus may return to the environment, therefore contributing to preserve its teleomorphic (sexual) and anamorphic (asexual) forms in a defined and protected natural habitat. PMID:16473563

  14. Transcription levels of CHS5 and CHS4 genes in Paracoccidioides brasiliensis mycelial phase, respond to alterations in external osmolarity, oxidative stress and glucose concentration.

    PubMed

    Niño-Vega, Gustavo A; Sorais, Françoise; San-Blas, Gioconda

    2009-10-01

    The complete sequence of Paracoccidioides brasiliensis CHS5 gene, encoding a putative chitin synthase revealed a 5583nt open reading frame, interrupted by three introns of 82, 87 and 97bp (GenBank Accession No EF654132). The deduced protein contains 1861 amino acids with a predicted molecular weight of 206.9kDa. Both its large size and the presence of a N-terminal region of approx. 800 residues with a characteristic putative myosin motor-like domain, allow us to include PbrChs5 into class V fungal chitin synthases. Sequence analysis of over 4kb from the 5' UTR region in CHS5, revealed the presence of a previously reported CHS4 gene in P. brasiliensis, arranged in a head-to-head configuration with CHS5. A motif search in this shared region showed the presence of stress response elements (STREs), three binding sites for the transcription activators Rlm1p (known to be stimulated by hypo-osmotic stress) and clusters of Adr1 (related to glucose repression). A quantitative RT-PCR analysis pointed to changes in transcription levels for both genes following oxidative stress, alteration of external osmolarity and under glucose-repressible conditions, suggesting a common regulatory mechanism of transcription. PMID:19616626

  15. The Effects of Paracoccidioides brasiliensis Infection on GM-CSF- and M-CSF-Induced Mouse Bone Marrow-Derived Macrophage from Resistant and Susceptible Mice Strains

    PubMed Central

    de Souza Silva, Calliandra; Tavares, Aldo Henrique; Sousa Jeronimo, Marcio; Soares de Lima, Yasmin; da Silveira Derengowski, Lorena; Lorenzetti Bocca, Anamélia; Silva-Pereira, Ildinete

    2015-01-01

    Considering the importance of macrophages as the first line of defense against fungal infection and the different roles played by the two M1- and M2-like polarized macrophages, we decided to evaluate the effects of Paracoccidioides brasiliensis infection on GM-CSF- and M-CSF-induced bone marrow-derived macrophages (BMM) from the A/J and B10.A mouse strains, an established model of resistance/susceptibility to PCM, respectively. Upon differentiation, the generated GM- or M-BMMs were characterized by morphological analyses, gene expression profiles, and cytokines production. Our main results demonstrate that GM-BMMs derived from A/J and B.10 produced high levels of pro- and anti-inflammatory cytokines that may contribute to generate an unbalanced early immune response. In accordance with the literature, the B10.A susceptible mice lineage has an innate tendency to polarize into M1-like phenotype, whereas the opposite phenotype occurs in A/J resistance mice. In this context, our data support that susceptibility and resistance are strongly correlated with M1 and M2 polarization, respectively. PMID:26543326

  16. C-Npys (S-3-nitro-2-pyridinesulfenyl) and peptide derivatives can inhibit a serine-thiol proteinase activity from Paracoccidioides brasiliensis

    PubMed Central

    Matsuo, Alisson L.; Carmona, Adriana K.; Silva, Luiz S.; Cunha, Carlos E. L.; Nakayasu, Ernesto S.; Almeida, Igor C.; Juliano, Maria A.; Puccia, Rosana

    2013-01-01

    The inhibitory capacity of C-Npys (S-[3-nitro-2-pyridinesulfenyl]) derivatives over thiol-containing serine proteases has never been tested. In the present work we used an extracellular serine-thiol proteinase activity from the fungal pathogen Paracoccidioides brasiliensis (PbST) to describe a potent inhibitory capacity of Bzl-C(Npys)KRLTL-NH2 and Bzl-MKRLTLC(Npys)-NH2. The assays were performed with PbST enriched upon affinity chromatography in a p-aminobenzamidine (pABA)-Sepharose column. Although PbST can cleave the fluorescence resonance energy transfer peptide Abz-MKRLTL-EDDnp between L-T, the C(Npys) derivatives were not substrates nor were they toxic in a cell detachment assay, allowing therapeutic use. The best inhibitor was Bzl-C(Npys)KRLTL-NH2 (Ki = 16 nM), suggesting that the peptide sequence promoted a favorable interaction, especially when C(Npys) was placed at a further position from the L-T bond, at the N-terminus. Inhibition was completely reverted with dithioerythritol, indicating that it was due to the reactivity of the C(Npys) moiety with a free SH- group. PMID:17328865

  17. Influence of 17?-Estradiol on Gene Expression of Paracoccidioides during Mycelia-to-Yeast Transition

    PubMed Central

    Shankar, Jata; Wu, Thomas D.; Clemons, Karl V.; Monteiro, Jomar P.; Mirels, Laurence F.; Stevens, David A.

    2011-01-01

    Background Paracoccidioides is the causative agent of paracoccidioidomycosis, a systemic mycosis endemic to Latin America. Infection is initiated by inhalation of conidia (C) or mycelial (M) fragments, which subsequently differentiate into yeast (Y). Epidemiological studies show a striking predominance of paracoccidioidomycosis in adult men compared to premenopausal women. In vitro and in vivo studies suggest that the female hormone (17?-estradiol, E2) regulates or inhibits M-or-C-to-Y transition. In this study we have profiled transcript expression to understand the molecular mechanism of how E2 inhibits M-to-Y transition. Methodology We assessed temporal gene expression in strain Pb01 in the presence or absence of E2 at various time points through 9 days of the M-to-Y transition using an 11,000 element random-shear genomic DNA microarray and verified the results using quantitative real time-PCR. E2-regulated clones were sequenced to identify genes and biological function. Principal Findings E2-treatment affected gene expression of 550 array elements, with 331 showing up-regulation and 219 showing down-regulation at one or more time points (p?0.001). Genes with low expression after 4 or 12 h exposure to E2 belonged to pathways involved in heat shock response (hsp90 and hsp70), energy metabolism, and several retrotransposable elements. Y-related genes, ?-1,3-glucan synthase, mannosyltransferase and Y20, demonstrated low or delayed expression in E2-treated cultures. Genes potentially involved in signaling, such as palmitoyltransferase (erf2), small GTPase RhoA, phosphatidylinositol-4-kinase, and protein kinase (serine/threonine) showed low expression in the presence of E2, whereas a gene encoding for an arrestin domain-containing protein showed high expression. Genes related to ubiquitin-mediated protein degradation, and oxidative stress response genes were up-regulated by E2. Conclusion This study characterizes the effect of E2 at the molecular level on the inhibition of the M-to-Y transition and is indicative that the inhibitory actions of E2 may be working through signaling genes that regulate dimorphism. PMID:22194832

  18. Immunodiagnosis of Paracoccidioidomycosis due to Paracoccidioides brasiliensis Using a Latex Test: Detection of Specific Antibody Anti-gp43 and Specific Antigen gp43

    PubMed Central

    dos Santos, Priscila Oliveira; Rodrigues, Anderson Messias; Fernandes, Geisa Ferreira; da Silva, Silvia Helena Marques; Burger, Eva; de Camargo, Zoilo Pires

    2015-01-01

    Background Paracoccidioidomycosis (PCM) is a life-threatening systemic disease and is a neglected public health problem in many endemic regions of Latin America. Though several diagnostic methods are available, almost all of them present with some limitations. Method/Principle Findings A latex immunoassay using sensitized latex particles (SLPs) with gp43 antigen, the immunodominant antigen of Paracoccidioides brasiliensis, or the monoclonal antibody mAb17c (anti-gp43) was evaluated for antibody or antigen detection in sera, cerebrospinal fluid (CSF), and bronchoalveolar lavage (BAL) from patients with PCM due to P. brasiliensis. The gp43-SLPs performed optimally to detect specific antibodies with high levels of sensitivity (98.46%, 95% CI 91.7–100.0), specificity (93.94%, 95% CI 87.3–97.7), and positive (91.4%) and negative (98.9%) predictive values. In addition, we propose the use of mAb17c-SLPs to detect circulating gp43, which would be particularly important in patients with immune deficiencies who fail to produce normal levels of immunoglobulins, achieving good levels of sensitivity (96.92%, 95% CI 89.3–99.6), specificity (88.89%, 95% CI 81.0–94.3), and positive (85.1%) and negative (97.8%) predictive values. Very good agreement between latex tests and double immune diffusion was observed for gp43-SLPs (k = 0.924) and mAb17c-SLPs (k = 0.850), which reinforces the usefulness of our tests for the rapid diagnosis of PCM in less than 10 minutes. Minor cross-reactivity occurred with sera from patients with other fungal infections. We successfully detected antigens and antibodies from CSF and BAL samples. In addition, the latex test was useful for monitoring PCM patients receiving therapy. Conclusions/Significance The high diagnostic accuracy, low cost, reduced assay time, and simplicity of this new latex test offer the potential to be commercialized and makes it an attractive diagnostic assay for use not only in clinics and medical mycology laboratories, but mainly in remote locations with limited laboratory infrastructure and/or minimally trained community health workers. PMID:25679976

  19. Interferon-gamma production by human neutrophils upon stimulation by IL-12, IL-15 and IL-18 and challenge with Paracoccidioides brasiliensis.

    PubMed

    Rodrigues, Daniela Ramos; Fernandes, Reginaldo Keller; Balderramas, Helanderson de Almeida; Penitenti, Marcimara; Bachiega, Tatiana Fernanda; Calvi, Sueli Aparecida; Dias-Melicio, Luciane Alarcão; Ikoma, Maura Rosane Valério; Soares, Ângela Maria Victoriano de Campos

    2014-09-01

    Paracoccidiodomycosis is a systemic mycosis caused by the fungus Paracoccidioides brasiliensis (Pb), which is endemic in Latin America. The host innate immune response against the fungus has been well characterized and several studies have shown the important role played by phagocytic cells. Our laboratory has studied the relationship between human neutrophils (PMNs)/Pb, focusing the effector mechanisms of these cells against the fungus. However, in last years, studies have shown that in addition to their phagocytic and killer functions, PMNs can modulate and instruct the immune response, since these cells have been shown to produce and release several cytokines. Thus, we evaluated whether PMNs stimulated with Pb can modulate the immune response to a Th1 phenotype through the production of IFN-?, as well as the role of "pattern-recognition receptors" (PRRs) such as TLR2, TLR4 and Dectin-1 in this production. Furthermore, we asked whether activation of the cells with the cytokines IL-12, IL-15 and IL-18 could result in increased levels of this cytokine. Peripheral blood PMNs obtained from 20 healthy donors were nonactivated or activated with IL-12, IL-15 or IL-18 in different concentrations and challenged with strain 18 Pb (Pb18) for 2 h, 4 h, 12 h, 24 h and 48 h and evaluated for IFN-? production, by ELISA. In other experiments, PMNs were treated with monoclonal antibodies anti-TLR2, TLR4 and Dectin-1, challenged with Pb and evaluated for IFN-? production. We found that Pb induces human PMNs to produce IFN-?, probably by binding to TLR4 and Dectin-1 receptors expressed by these cells. Moreover, IFN-? levels were significantly increased when cells were activated with each of the tested cytokines or a combination of two of them, being the association IL-12 plus IL-15 the most effective. The results support our hypothesis that during infection by Pb, human PMNs modulate the adaptive immune response to a Th1 response pattern, via IFN-? production. PMID:25022968

  20. Isolation of Paracoccidioides brasiliensis from the nine-banded armadillo Dasypus novemcinctus, in an endemic area for paracoccidioidomycosis in Colombia.

    PubMed

    Corredor, G G; Castaño, J H; Peralta, L A; Díez, S; Arango, M; McEwen, J; Restrepo, A

    1999-12-01

    The microniche of the dimorphic fungus Paracoccidiodes brasiliensisremains undefined in spite of the many attempts to isolate it from natural sources. Until recently, knowledge was also scanty concerning the presence of natural infections in animals; however, in the last decade, the fungus has been repeatedly isolated from the nine-banded armadillo, Dasypus novemcinctusin Brazil. A study aimed at determining the presence of infected armadillos in one of the paracoccidioidomycosis endemic areas of Colombia (Manizales, Department of Caldas) was undertaken. Based on the records of paracoccidioidomycosis patients available in the regional hospital, we selected a locality corresponding to a permanent resident, and found that it also had armadillo's burrows. Counting with the proper authorization, two animals were captured, sacrificed under prolonged anaesthesia and various internal organs cultured in mycological media. PCR with specific P. brasiliensis'primers was also done. The fungus was isolated from the mesenteric lymph node of one of the animals; fungal DNA amplification was positive in the same specimen as well as in the liver. The isolate from the Colombian armadillo indicates that these animals are regular hosts to P. brasiliensis in at least two endemic countries. Due to the restricted life pattern of these mammals they represent an important link with the natural habitat of the fungus. Consequently, a study of their movements and habits could prove rewarding in the search for this habitat. PMID:18473551

  1. Insights into the plant polysaccharide degradation potential of the xylanolytic yeast Pseudozyma brasiliensis.

    PubMed

    Kaupert Neto, Antonio Adalberto; Borin, Gustavo Pagotto; Goldman, Gustavo Henrique; Damásio, André Ricardo de Lima; Oliveira, Juliana Velasco de Castro

    2016-03-01

    In second-generation (2G) bioethanol production, plant cell-wall polysaccharides are broken down to release fermentable sugars. The enzymes of this process are classified as carbohydrate-active enzymes (CAZymes) and contribute substantially to the cost of biofuel production. A novel basidiomycete yeast species, Pseudozyma brasiliensis, was recently discovered. It produces an endo-β-1,4-xylanase with a higher specific activity than other xylanases. This enzyme is essential for the hydrolysis of biomass-derived xylan and has an important role in 2G bioethanol production. In spite of the P. brasiliensis biotechnological potential, there is no information about how it breaks down polysaccharides. For the first time, we characterized the secretome of P. brasiliensis grown on different carbon sources (xylose, xylan, cellobiose and glucose) and also under starvation conditions. The growth and consumption of each carbohydrate and the activity of the CAZymes of culture supernatants were analyzed. The CAZymes found in its secretomes, validated by enzymatic assays, have the potential to hydrolyze xylan, mannan, cellobiose and other polysaccharides. The data show that this yeast is a potential source of hydrolases, which can be used for biomass saccharification. PMID:26712719

  2. Microplate alamarBlue Assay for Paracoccidioides Susceptibility Testing

    PubMed Central

    de Paula e Silva, A. C. A.; Oliveira, H. C.; Silva, J. F.; Sangalli-Leite, F.; Scorzoni, L.; Fusco-Almeida, A. M.

    2013-01-01

    CLSI method M27-A3 is not available for use with dimorphic fungi, such as those of the Paracoccidioides genus. In this study, we developed a microdilution method and added the alamarBlue reagent to test the responses of Paracoccidioides brasiliensis and Paracoccidioides lutzii against amphotericin B and itraconazole antifungals. The test proved to be sensitive, practical, and inexpensive and can be used to monitor the activity of low-growth microorganisms and their response to various drugs. PMID:23345296

  3. Characterization of Cell Wall Lipids from the Pathogenic Phase of Paracoccidioides brasiliensis Cultivated in the Presence or Absence of Human Plasma

    PubMed Central

    Gazos-Lopes, Felipe; Vallejo, Milene C.; Matsuo, Alisson L.; Almeida, Igor C.; Puccia, Rosana

    2013-01-01

    Background The fungal cell wall is a complex and dynamic outer structure. In pathogenic fungi its components interact with the host, determining the infection fate. The present work aimed to characterize cell wall lipids from P. brasiliensis grown in the presence and absence of human plasma. We compared the results from isolates Pb3 and Pb18, which represent different phylogenetic species that evoke distinct patterns of experimental paracoccidioidomycosis. Methodology/Principal Findings We comparatively characterized cell wall phospholipids, fatty acids, sterols, and neutral glycolipids by using both electrospray ionization- and gas chromatography-mass spectrometry analyses of lipids extracted with organic solvents followed by fractionation in silica-gel-60. We detected 49 phospholipid species in Pb3 and 38 in Pb18, including phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylglycerol, phosphatidylinositol, and phosphatidic acid. In both Pb3 and Pb18, PC and PE had the most numerous species. Among the fatty acids, C18?1 and C18?2 were the most abundant species in both isolates, although C18?2 was more abundant in Pb18. There was a different effect of plasma supplementation on fatty acids depending on the fungal isolate. The prevalent glycolipid species was Hex-C18?0-OH/d19?2-Cer, although other four minor species were also detected. The most abundant sterol in all samples was brassicasterol. Distinct profiles of cell wall and total yeast sterols suggested that the preparations were enriched for cell wall components. The presence of plasma in the culture medium specially increased cell wall brassicasterol abundance and also other lipids. Conclusions/Significance We here report an original comparative lipidomic analysis of P. brasiliensis cell wall. Our results open doors to understanding the role of cell wall lipids in fungal biology, and interaction with anti-fungal drugs and the host. PMID:23691038

  4. Pseudozyma brasiliensis sp. nov., a xylanolytic, ustilaginomycetous yeast species isolated from an insect pest of sugarcane roots.

    PubMed

    Oliveira, Juliana Velasco de Castro; Borges, Thuanny A; Corrêa dos Santos, Renato Augusto; Freitas, Larissa F D; Rosa, Carlos Augusto; Goldman, Gustavo Henrique; Riaño-Pachón, Diego Mauricio

    2014-06-01

    A novel ustilaginomycetous yeast isolated from the intestinal tract of an insect pest of sugarcane roots in Ribeirão Preto, São Paulo State, Brazil, represents a novel species of the genus Pseudozyma based on molecular analyses of the D1/D2 rDNA large subunit and the internal transcribed spacer (ITS1+ITS2) regions. The name Pseudozyma brasiliensis sp. nov. is proposed for this species, with GHG001(T) (?=?CBS 13268(T)?=?UFMG-CM-Y307(T)) as the type strain. P. brasiliensis sp. nov. is a sister species of Pseudozyma vetiver, originally isolated from leaves of vetiver grass and sugarcane in Thailand. P. brasiliensis sp. nov. is able to grow well with xylan as the sole carbon source and produces high levels of an endo-1,4-xylanase that has a higher specific activity in comparison with other eukaryotic xylanases. This enzyme has a variety of industrial applications, indicating the great biotechnological potential of P. brasiliensis. PMID:24682702

  5. Identification and Analysis of the Role of Superoxide Dismutases Isoforms in the Pathogenesis of Paracoccidioides spp.

    PubMed Central

    Tamayo, Diana; Muñoz, José F.; Lopez, Ángela; Urán, Martha; Herrera, Juan; Borges, Clayton L.; Restrepo, Ángela; Soares, Celia M.; Taborda, Carlos P.; Almeida, Agostinho J.; McEwen, Juan G.; Hernández, Orville

    2016-01-01

    The ability of Paracoccidioides to defend itself against reactive oxygen species (ROS) produced by host effector cells is a prerequisite to survive. To counteract these radicals, Paracoccidioides expresses, among different antioxidant enzymes, superoxide dismutases (SODs). In this study, we identified six SODs isoforms encoded by the Paracoccidioides genome. We determined gene expression levels of representative isolates of the phylogenetic lineages of Paracoccidioides spp. (S1, PS2, PS3 and Pb01-like) using quantitative RT-PCR. Assays were carried out to analyze SOD gene expression of yeast cells, mycelia cells, the mycelia-to-yeast transition and the yeast-to-mycelia germination, as well as under treatment with oxidative agents and during interaction with phagocytic cells. We observed an increased expression of PbSOD1 and PbSOD3 during the transition process, exposure to oxidative agents and interaction with phagocytic cells, suggesting that these proteins could assist in combating the superoxide radicals generated during the host-pathogen interaction. Using PbSOD1 and PbSOD3 knockdown strains we showed these genes are involved in the response of the fungus against host effector cells, particularly the oxidative stress response, and in a mouse model of infection. Protein sequence analysis together with functional analysis of knockdown strains seem to suggest that PbSOD3 expression is linked with a pronounced extracellular activity while PbSOD1 seems more related to intracellular requirements of the fungus. Altogether, our data suggests that P. brasiliensis actively responds to the radicals generated endogenously during metabolism and counteracts the oxidative burst of immune cells by inducing the expression of SOD isoforms. PMID:26963091

  6. Identification and Analysis of the Role of Superoxide Dismutases Isoforms in the Pathogenesis of Paracoccidioides spp.

    PubMed

    Tamayo, Diana; Muñoz, José F; Lopez, Ángela; Urán, Martha; Herrera, Juan; Borges, Clayton L; Restrepo, Ángela; Soares, Celia M; Taborda, Carlos P; Almeida, Agostinho J; McEwen, Juan G; Hernández, Orville

    2016-03-01

    The ability of Paracoccidioides to defend itself against reactive oxygen species (ROS) produced by host effector cells is a prerequisite to survive. To counteract these radicals, Paracoccidioides expresses, among different antioxidant enzymes, superoxide dismutases (SODs). In this study, we identified six SODs isoforms encoded by the Paracoccidioides genome. We determined gene expression levels of representative isolates of the phylogenetic lineages of Paracoccidioides spp. (S1, PS2, PS3 and Pb01-like) using quantitative RT-PCR. Assays were carried out to analyze SOD gene expression of yeast cells, mycelia cells, the mycelia-to-yeast transition and the yeast-to-mycelia germination, as well as under treatment with oxidative agents and during interaction with phagocytic cells. We observed an increased expression of PbSOD1 and PbSOD3 during the transition process, exposure to oxidative agents and interaction with phagocytic cells, suggesting that these proteins could assist in combating the superoxide radicals generated during the host-pathogen interaction. Using PbSOD1 and PbSOD3 knockdown strains we showed these genes are involved in the response of the fungus against host effector cells, particularly the oxidative stress response, and in a mouse model of infection. Protein sequence analysis together with functional analysis of knockdown strains seem to suggest that PbSOD3 expression is linked with a pronounced extracellular activity while PbSOD1 seems more related to intracellular requirements of the fungus. Altogether, our data suggests that P. brasiliensis actively responds to the radicals generated endogenously during metabolism and counteracts the oxidative burst of immune cells by inducing the expression of SOD isoforms. PMID:26963091

  7. Peptide Immunization as an Adjuvant to Chemotherapy in Mice Challenged Intratracheally with Virulent Yeast Cells of Paracoccidioides brasiliensis

    PubMed Central

    Marques, A. F.; da Silva, M. B.; Juliano, M. A. P.; Travassos, L. R.; Taborda, C. P.

    2006-01-01

    Immunization with peptide P10, derived from gp43, and chemotherapy were used together in an attempt to improve treatment of paracoccidioidomycosis and prevent relapses. The combined treatment showed an additive protective effect when administered at 48 h or 30 days after intratracheal challenge. Its use is recommended to improve regular chemotherapy and reduce the duration of treatment. PMID:16870776

  8. Genus Paracoccidioides: Species Recognition and Biogeographic Aspects

    PubMed Central

    Theodoro, Raquel Cordeiro; Teixeira, Marcus de Melo; Felipe, Maria Sueli Soares; Paduan, Karina dos Santos; Ribolla, Paulo Martins; San-Blas, Gioconda; Bagagli, Eduardo

    2012-01-01

    Background Paracoccidioidomycosis is a systemic mycosis caused by Paracoccidioides brasiliensis (species S1, PS2, PS3), and Paracoccidioides lutzii. This work aimed to differentiate species within the genus Paracoccidioides, without applying multilocus sequencing, as well as to obtain knowledge of the possible speciation processes. Methodology/Principal Findings Single nucleotide polymorphism analysis on GP43, ARF and PRP8 intein genes successfully distinguished isolates into four different species. Morphological evaluation indicated that elongated conidia were observed exclusively in P. lutzii isolates, while all other species (S1, PS2 and PS3) were indistinguishable. To evaluate the biogeographic events that led to the current geographic distribution of Paracoccidioides species and their sister species, Nested Clade and Likelihood Analysis of Geographic Range Evolution (LAGRANGE) analyses were applied. The radiation of Paracoccidioides started in northwest South America, around 11–32 million years ago, as calculated on the basis of ARF substitution rate, in the BEAST program. Vicariance was responsible for the divergence among S1, PS2 and P. lutzii and a recent dispersal generated the PS3 species, restricted to Colombia. Taking into account the ancestral areas revealed by the LAGRANGE analysis and the major geographic distribution of L. loboi in the Amazon basin, a region strongly affected by the Andes uplift and marine incursions in the Cenozoic era, we also speculate about the effect of these geological events on the vicariance between Paracoccidioides and L. loboi. Conclusions/Significance The use of at least 3 SNPs, but not morphological criteria, as markers allows us to distinguish among the four cryptic species of the genus Paracoccidioides. The work also presents a biogeographic study speculating on how these species might have diverged in South America, thus contributing to elucidating evolutionary aspects of the genus Paracoccidioides. PMID:22666382

  9. P. brasiliensis Virulence Is Affected by SconC, the Negative Regulator of Inorganic Sulfur Assimilation

    PubMed Central

    Menino, João Filipe; Saraiva, Margarida; Gomes-Rezende, Jéssica; Sturme, Mark; Pedrosa, Jorge; Castro, António Gil; Ludovico, Paula; Goldman, Gustavo H.; Rodrigues, Fernando

    2013-01-01

    Conidia/mycelium-to-yeast transition of Paracoccidioidesbrasiliensis is a critical step for the establishment of paracoccidioidomycosis, a systemic mycosis endemic in Latin America. Thus, knowledge of the factors that mediate this transition is of major importance for the design of intervention strategies. So far, the only known pre-requisites for the accomplishment of the morphological transition are the temperature shift to 37°C and the availability of organic sulfur compounds. In this study, we investigated the auxotrophic nature to organic sulfur of the yeast phase of Paracoccidioides, with special attention to P. brasiliensis species. For this, we addressed the role of SconCp, the negative regulator of the inorganic sulfur assimilation pathway, in the dimorphism and virulence of this pathogen. We show that down-regulation of SCONC allows initial steps of mycelium-to-yeast transition in the absence of organic sulfur compounds, contrarily to the wild-type fungus that cannot undergo mycelium-to-yeast transition under such conditions. However, SCONC down-regulated transformants were unable to sustain yeast growth using inorganic sulfur compounds only. Moreover, pulses with inorganic sulfur in SCONC down-regulated transformants triggered an increase of the inorganic sulfur metabolism, which culminated in a drastic reduction of the ATP and NADPH cellular levels and in higher oxidative stress. Importantly, the down-regulation of SCONC resulted in a decreased virulence of P. brasiliensis, as validated in an in vivo model of infection. Overall, our findings shed light on the inability of P. brasiliensis yeast to rely on inorganic sulfur compounds, correlating its metabolism with cellular energy and redox imbalances. Furthermore, the data herein presented reveal SconCp as a novel virulence determinant of P. brasiliensis. PMID:24066151

  10. Paracoccidioides-host Interaction: An Overview on Recent Advances in the Paracoccidioidomycosis

    PubMed Central

    de Oliveira, Haroldo C.; Assato, Patrícia A.; Marcos, Caroline M.; Scorzoni, Liliana; de Paula E Silva, Ana C. A.; Da Silva, Julhiany De Fátima; Singulani, Junya de Lacorte; Alarcon, Kaila M.; Fusco-Almeida, Ana M.; Mendes-Giannini, Maria J. S.

    2015-01-01

    Paracoccidioides brasiliensis and P. lutzii are etiologic agents of paracoccidioidomycosis (PCM), an important endemic mycosis in Latin America. During its evolution, these fungi have developed characteristics and mechanisms that allow their growth in adverse conditions within their host through which they efficiently cause disease. This process is multi-factorial and involves host–pathogen interactions (adaptation, adhesion, and invasion), as well as fungal virulence and host immune response. In this review, we demonstrated the glycoproteins and polysaccharides network, which composes the cell wall of Paracoccidioides spp. These are important for the change of conidia or mycelial (26°C) to parasitic yeast (37°C). The morphological switch, a mechanism for the pathogen to adapt and thrive inside the host, is obligatory for the establishment of the infection and seems to be related to pathogenicity. For these fungi, one of the most important steps during the interaction with the host is the adhesion. Cell surface proteins called adhesins, responsible for the first contact with host cells, contribute to host colonization and invasion by mediating this process. These fungi also present the capacity to form biofilm and through which they may evade the host’s immune system. During infection, Paracoccidioides spp. can interact with different host cell types and has the ability to modulate the host’s adaptive and/or innate immune response. In addition, it participates and interferes in the coagulation system and phenomena like cytoskeletal rearrangement and apoptosis. In recent years, Paracoccidioides spp. have had their endemic areas expanding in correlation with the expansion of agriculture. In response, several studies were developed to understand the infection using in vitro and in vivo systems, including alternative non-mammal models. Moreover, new advances were made in treating these infections using both well-established and new antifungal agents. These included natural and/or derivate synthetic substances as well as vaccines, peptides, and anti-adhesins sera. Because of all the advances in the PCM study, this review has the objective to summarize all of the recent discoveries on Paracoccidioides-host interaction, with particular emphasis on fungi surface proteins (molecules that play a fundamental role in the adhesion and/or dissemination of the fungi to host-cells), as well as advances in the treatment of PCM with new and well-established antifungal agents and approaches. PMID:26635779

  11. Importance of adhesins in virulence of Paracoccidioides spp.

    PubMed Central

    de Oliveira, Haroldo C.; da Silva, Julhiany de Fátima; Scorzoni, Liliana; Marcos, Caroline M.; Rossi, Suelen A.; de Paula e Silva, Ana C. A.; Assato, Patrícia A.; da Silva, Rosângela A. M.; Fusco-Almeida, Ana M.; Mendes-Giannini, Maria J. S.

    2015-01-01

    Members of the Paracoccidioides genus are the etiologic agents of paracoccidioidomycosis (PCM). This genus is composed of two species: Paracoccidioides brasiliensis and Paracoccidioides lutzii. The correct molecular taxonomic classification of these fungi has created new opportunities for studying and understanding their relationships with their hosts. Paracoccidioides spp. have features that permit their growth under adverse conditions, enable them to adhere to and invade host tissues and may contribute to disease development. Cell wall proteins called adhesins facilitate adhesion and are capable of mediating fungi-host interactions during infection. This study aimed to evaluate the adhesion profile of two species of the genus Paracoccidioides, to analyze the expression of adhesin-encoding genes by real-time PCR and to relate these results to the virulence of the species, as assessed using a survival curve in mice and in Galleria mellonella after blocking the adhesins. A high level of heterogeneity was observed in adhesion and adhesin expression, showing that the 14-3-3 and enolase molecules are the most highly expressed adhesins during pathogen-host interaction. Additionally, a survival curve revealed a correlation between the adhesion rate and survival, with P. brasiliensis showing higher adhesion and adhesin expression levels and greater virulence when compared with P. lutzii. After blocking 14-3-3 and enolase adhesins, we observed modifications in the virulence of these two species, revealing the importance of these molecules during the pathogenesis of members of the Paracoccidioides genus. These results revealed new insights into the host-pathogen interaction of this genus and may enhance our understanding of different isolates that could be useful for the treatment of this mycosis. PMID:25914695

  12. Serology of Paracoccidioidomycosis Due to Paracoccidioides lutzii

    PubMed Central

    Gegembauer, Gregory; Araujo, Leticia Mendes; Pereira, Edy Firmina; Rodrigues, Anderson Messias; Paniago, Anamaria Mello Miranda; Hahn, Rosane Christine; de Camargo, Zoilo Pires

    2014-01-01

    Paracoccidioides lutzii is a new agent of paracoccidioidomycosis (PCM) and has its epicenter localized to the Central-West region of Brazil. Serological diagnosis of PCM caused by P. lutzii has not been established. This study aimed to develop new antigenic preparations from P. lutzii and to apply them in serological techniques to improve the diagnosis of PCM due to P. lutzii. Paracoccidioides lutzii exoantigens, cell free antigen (CFA), and a TCA-precipitated antigen were evaluated in immunodiffusion (ID) tests using a total of 89 patient sera from the Central-West region of Brazil. Seventy-two sera were defined as reactive for P. brasiliensis using traditional antigens (AgPbB339 and gp43). Non-reactive sera for traditional antigens (n = 17) were tested with different P. lutzii preparations and P. lutzii CFA showed 100% reactivity. ELISA was found to be a very useful test to titer anti-P. lutzii antibodies using P. lutzii-CFA preparations. Sera from patients with PCM due to P. lutzii presented with higher antibody titers than PCM due to P. brasiliensis and heterologous sera. In western blot, sera from patients with PCM due to P. lutzii were able to recognize antigenic molecules from the P. lutzii-CFA antigen, but sera from patients with PCM due to P. brasiliensis could not recognize any P. lutzii molecules. Due to the facility of preparing P. lutzii CFA antigens we recommend its use in immunodiffusion tests for the diagnosis of PCM due to P. lutzii. ELISA and western blot can be used as complementary tests. PMID:25032829

  13. Cyclopalladated Compound 7a Induces Apoptosis- and Autophagy-Like Mechanisms in Paracoccidioides and Is a Candidate for Paracoccidioidomycosis Treatment.

    PubMed

    Arruda, Denise C; Matsuo, Alisson L; Silva, Luiz S; Real, Fernando; Leitão, Natanael P; Pires, Jhon H S; Caires, Antonio Carlos F; Garcia, Daniel M; Cunha, Fernanda F M; Puccia, Rosana; Longo, Larissa V G

    2015-12-01

    Paracoccidioidomycosis (PCM), caused by Paracoccidioides species, is the main cause of death due to systemic mycoses in Brazil and other Latin American countries. Therapeutic options for PCM and other systemic mycoses are limited and time-consuming, and there are high rates of noncompliance, relapses, toxic side effects, and sequelae. Previous work has shown that the cyclopalladated 7a compound is effective in treating several kinds of cancer and parasitic Chagas disease without significant toxicity in animals. Here we show that cyclopalladated 7a inhibited the in vitro growth of Paracoccidioides lutzii Pb01 and P. brasiliensis isolates Pb18 (highly virulent), Pb2, Pb3, and Pb4 (less virulent) in a dose-response manner. Pb18 was the most resistant. Opportunistic Candida albicans and Cryptococcus neoformans were also sensitive. BALB/c mice showed significantly lighter lung fungal burdens when treated twice a day for 20 days with a low cyclopalladated 7a dose of 30 μg/ml/day for 30 days after intratracheal infection with Pb18. Electron microscopy images suggested that apoptosis- and autophagy-like mechanisms are involved in the fungal killing mechanism of cyclopalladated 7a. Pb18 yeast cells incubated with the 7a compound showed remarkable chromatin condensation, DNA degradation, superoxide anion production, and increased metacaspase activity suggestive of apoptosis. Autophagy-related killing mechanisms were suggested by increased autophagic vacuole numbers and acidification, as indicated by an increase in LysoTracker and monodansylcadaverine (MDC) staining in cyclopalladated 7a-treated Pb18 yeast cells. Considering that cyclopalladated 7a is highly tolerated in vivo and affects yeast fungal growth through general apoptosis- and autophagy-like mechanisms, it is a novel promising drug for the treatment of PCM and other mycoses. PMID:26349827

  14. Occurrence of Paracoccidioides lutzii in the Amazon Region: Description of Two Cases

    PubMed Central

    Marques-da-Silva, Silvia Helena; Messias Rodrigues, Anderson; de Hoog, G. Sybren; Silveira-Gomes, Fabíola; Pires de Camargo, Zoilo

    2012-01-01

    Paracoccidioidomycosis (PCM), the most important human systemic mycosis in Latin America, is known to be caused by at least four different phylogenetic lineages within the Paracoccidioides brasiliensis complex, including S1, PS2, PS3, and Pb01-like group. Herein, we describe two cases of PCM in patients native from the Amazon region. The disease was originally thought to have been caused by P. brasiliensis. Despite the severity of the cases, sera from the patients were negative in immunodiffusion tests using the standard exoantigen from P. brasiliensis B-339. However, a positive response was recorded with an autologous preparation of Paracoccidioides lutzii exoantigen. A phylogenetic approach based on the gp43 and ARF loci revealed high similarity between our clinical isolates and the Pb01-like group. The occurrence of PCM caused by P. lutzii in the Brazilian Amazon (Pará State) was thus proven. The incidence of PCM caused by P. lutzii may be underestimated in northern Brazil. PMID:22927496

  15. Occurrence of Paracoccidioides lutzii in the Amazon region: description of two cases.

    PubMed

    Marques-da-Silva, Silvia Helena; Rodrigues, Anderson Messias; de Hoog, G Sybren; Silveira-Gomes, Fabíola; Camargo, Zoilo Pires de

    2012-10-01

    Paracoccidioidomycosis (PCM), the most important human systemic mycosis in Latin America, is known to be caused by at least four different phylogenetic lineages within the Paracoccidioides brasiliensis complex, including S1, PS2, PS3, and Pb01-like group. Herein, we describe two cases of PCM in patients native from the Amazon region. The disease was originally thought to have been caused by P. brasiliensis. Despite the severity of the cases, sera from the patients were negative in immunodiffusion tests using the standard exoantigen from P. brasiliensis B-339. However, a positive response was recorded with an autologous preparation of Paracoccidioides lutzii exoantigen. A phylogenetic approach based on the gp43 and ARF loci revealed high similarity between our clinical isolates and the Pb01-like group. The occurrence of PCM caused by P. lutzii in the Brazilian Amazon (Pará State) was thus proven. The incidence of PCM caused by P. lutzii may be underestimated in northern Brazil. PMID:22927496

  16. Transcriptional profile of Paracoccidioides spp. in response to itraconazole

    PubMed Central

    2014-01-01

    Background Itraconazole is currently used to treat paracoccidioidomycosis. The mechanism of action of azoles has been elucidated in some fungi, although little is known regarding its mechanism of action in Paracoccidioides spp. The present work focused on identification of regulated transcripts using representational difference analysis of Paracoccidioides spp. yeast cells treated with itraconazole for 1 and 2 h. Results Paracoccidioides Pb01 genes up-regulated by itraconazole included genes involved in cellular transport, metabolism/energy, transcription, cell rescue, defense and virulence. ERG11, ERG6, ERG3, ERG5 and ERG25 were up-regulated at multiple time points. In vivo infection experiments in mice corroborated the in vitro results. Ergosterol levels and distribution were evaluated in Paracoccidioides Pb18 yeast cells, and the results demonstrate that both factors were changed in the fungus treated with itraconazole. Conclusion To our knowledge, this is the first transcriptional analysis of Paracoccidioides spp. exposed to a triazole drug. Here acetyl seems to be intensively produced from different metabolic pathways to produce ergosterol by the action of ergosterol synthesis related enzymes, which were also affected in other fungi. Among the genes affected, we identified genes in common with other fungi, as well as genes unique to Paracoccidioides Pb01. Those genes could be considered target to new drugs. Voltage-gated Ca2+ alpha subunit (CAV), Tetracycline resistance protein (TETA) and Hemolisyn-iii channel protein (HLYiii) were found only here and a probably involvement with resistence to itraconazole could be investigated in the future. However our findings do not permit inference to current clinical practice. PMID:24690401

  17. Advances and challenges in paracoccidioidomycosis serology caused by Paracoccidioides species complex: an update.

    PubMed

    da Silva, Julhiany de Fátima; de Oliveira, Haroldo Cesar; Marcos, Caroline Maria; Assato, Patricia Akemi; Fusco-Almeida, Ana Marisa; Mendes-Giannini, Maria José Soares

    2016-01-01

    Understanding the possible methodologies for the rapid and inexpensive identification of fungal infections is essential for disease diagnosis, but there are some limitations. To help with this problem, serological methods that detect antigens or antibodies are widely used and are useful for the diagnosis of paracoccidioidomycosis (PCM) through the detection of gp43, which is the main antigen employed for the immunodiagnosis of this disease caused by Paracoccidioides brasiliensis. However, the use of gp43 has become restricted because it was recently found that this marker is not identified in the infections caused by Paracoccidioides lutzii. Therefore, it is necessary to identify new antigens in both species or antigens specific for P. lutzii to decrease the morbidity and/or mortality associated with PCM. This review provides a discussion of new diagnostic challenges after the recent discoveries regarding the taxonomy of the Paracoccidioides genus. PMID:26494541

  18. Intermolecular interactions of the malate synthase of Paracoccidioides spp

    PubMed Central

    2013-01-01

    Background The fungus Paracoccidioides spp is the agent of paracoccidioidomycosis (PCM), a pulmonary mycosis acquired by the inhalation of fungal propagules. Paracoccidioides malate synthase (PbMLS) is important in the infectious process of Paracoccidioides spp because the transcript is up-regulated during the transition from mycelium to yeast and in yeast cells during phagocytosis by murine macrophages. In addition, PbMLS acts as an adhesin in Paracoccidioides spp. The evidence for the multifunctionality of PbMLS indicates that it could interact with other proteins from the fungus and host. The objective of this study was to identify and analyze proteins that possibly bind to PbMLS (PbMLS-interacting proteins) because protein interactions are intrinsic to cell processes, and it might be possible to infer the function of a protein through the identification of its ligands. Results The search for interactions was performed using an in vivo assay with a two-hybrid library constructed in S. cerevisiae; the transcripts were sequenced and identified. In addition, an in vitro assay using pull-down GST methodology with different protein extracts (yeast, mycelium, yeast-secreted proteins and macrophage) was performed, and the resulting interactions were identified by mass spectrometry (MS). Some of the protein interactions were confirmed by Far-Western blotting using specific antibodies, and the interaction of PbMLS with macrophages was validated by indirect immunofluorescence and confocal microscopy. In silico analysis using molecular modeling, dynamics and docking identified the amino acids that were involved in the interactions between PbMLS and PbMLS-interacting proteins. Finally, the interactions were visualized graphically using Osprey software. Conclusion These observations indicate that PbMLS interacts with proteins that are in different functional categories, such as cellular transport, protein biosynthesis, modification and degradation of proteins and signal transduction. These data suggest that PbMLS could play different roles in the fungal cell. PMID:23672539

  19. Evaluating Common Humoral Responses against Fungal Infections with Yeast Protein Microarrays.

    PubMed

    Coelho, Paulo S R; Im, Hogune; Clemons, Karl V; Snyder, Michael P; Stevens, David A

    2015-09-01

    We profiled the global immunoglobulin response against fungal infection by using yeast protein microarrays. Groups of CD-1 mice were infected systemically with human fungal pathogens (Coccidioides posadasii, Candida albicans, or Paracoccidioides brasiliensis) or inoculated with PBS as a control. Another group was inoculated with heat-killed yeast (HKY) of Saccharomyces cerevisiae. After 30 days, serum from mice in the groups were collected and used to probe S. cerevisiae protein microarrays containing 4800 full-length glutathione S-transferase (GST)-fusion proteins. Antimouse IgG conjugated with Alexafluor 555 and anti-GST antibody conjugated with Alexafluor 647 were used to detect antibody-antigen interactions and the presence of GST-fusion proteins, respectively. Serum after infection with C. albicans reacted with 121 proteins: C. posadasii, 81; P. brasiliensis, 67; and after HKY, 63 proteins on the yeast protein microarray, respectively. We identified a set of 16 antigenic proteins that were shared across the three fungal pathogens. These include retrotransposon capsid proteins, heat shock proteins, and mitochondrial proteins. Five of these proteins were identified in our previous study of fungal cell wall by mass spectrometry (Ann. N. Y. Acad. Sci. 2012, 1273, 44-51). The results obtained give a comprehensive view of the immunological responses to fungal infections at the proteomic level. They also offer insight into immunoreactive protein commonality among several fungal pathogens and provide a basis for a panfungal vaccine. PMID:26258609

  20. Transcriptome Profile of the Response of Paracoccidioides spp. to a Camphene Thiosemicarbazide Derivative

    PubMed Central

    do Carmo Silva, Lívia; Tamayo Ossa, Diana Patrícia; Castro, Symone Vitoriano da Conceição; Bringel Pires, Ludmila; Alves de Oliveira, Cecília Maria; Conceição da Silva, Cleuza; Coelho, Narcimário Pereira; Bailão, Alexandre Melo; Parente-Rocha, Juliana Alves; Soares, Célia Maria de Almeida; Ruiz, Orville Hernández; Ochoa, Juan G. McEwen; Pereira, Maristela

    2015-01-01

    Paracoccidioidomycosis (PCM) is a systemic granulomatous human mycosis caused by fungi of the genus Paracoccidioides, which is geographically restricted to Latin America. Inhalation of spores, the infectious particles of the fungus, is a common route of infection. The PCM treatment of choice is azoles such as itraconazole, but sulfonamides and amphotericin B are used in some cases despite their toxicity to mammalian cells. The current availability of treatments highlights the need to identify and characterize novel targets for antifungal treatment of PCM as well as the need to search for new antifungal compounds obtained from natural sources or by chemical synthesis. To this end, we evaluated the antifungal activity of a camphene thiosemicarbazide derivative (TSC-C) compound on Paracoccidioides yeast. To determine the response of Paracoccidioides spp. to TSC-C, we analyzed the transcriptional profile of the fungus after 8 h of contact with the compound. The results demonstrate that Paracoccidioides lutzii induced the expression of genes related to metabolism; cell cycle and DNA processing; biogenesis of cellular components; cell transduction/signal; cell rescue, defense and virulence; cellular transport, transport facilities and transport routes; energy; protein synthesis; protein fate; transcription; and other proteins without classification. Additionally, we observed intensely inhibited genes related to protein synthesis. Analysis by fluorescence microscopy and flow cytometry revealed that the compound induced the production of reactive oxygen species. Using an isolate with down-regulated SOD1 gene expression (SOD1-aRNA), we sought to determine the function of this gene in the defense of Paracoccidioides yeast cells against the compound. Mutant cells were more susceptible to TSC-C, demonstrating the importance of this gene in response to the compound. The results presented herein suggest that TSC-C is a promising candidate for PCM treatment. PMID:26114868

  1. Phylogenetic analysis reveals a high level of speciation in the Paracoccidioides genus.

    PubMed

    Teixeira, Marcus M; Theodoro, Raquel C; de Carvalho, Maria J A; Fernandes, Larissa; Paes, Hugo C; Hahn, Rosane C; Mendoza, Leonel; Bagagli, Eduardo; San-Blas, Gioconda; Felipe, Maria Sueli S

    2009-08-01

    Paracoccidioidomycosis (PCM) is a systemic disease endemic to most of Latin America, with greatest impact in rural areas. The taxonomic status of one of the best studied Paracoccidioides isolates (Pb01) as P. brasiliensis remains unresolved due to its genomic differences from the other three previously described phylogenetic species (S1, PS2 and PS3; Carrero et al., 2008. Fungal Genet. Biol. 45, 605). Using the genealogic concordance method of phylogenetic species recognition (GCPSR) via maximum parsimony and Bayesian analysis, we identified a clade of 17 genotypically similar isolates, including Pb01, which are distinct from the S1/PS2/P3 clade. Consistent with GCPSR, this "Pb01-like" group can be considered a new phylogenetic species, since it is strongly supported by all independent and concatenated genealogies. "Pb01-like" species exhibit great sequence and morphological divergence from the S1/PS2/PS3 species clade, and we estimate that these groups last shared a common ancestor approximately 32 million years ago. In addition, recombination analysis revealed independent events inside both main groups suggesting reproductive isolation. Consequently, we recommend the formal description of the "Pb01-like" cluster as the new species Paracoccidioides lutzii, a tribute to Adolpho Lutz, discoverer of P. brasiliensis in 1908. PMID:19376249

  2. Extracellular vesicles from Paracoccidioides pathogenic species transport polysaccharide and expose ligands for DC-SIGN receptors

    PubMed Central

    da Silva, Roberta Peres; Heiss, Christian; Black, Ian; Azadi, Parastoo; Gerlach, Jared Q.; Travassos, Luiz R.; Joshi, Lokesh; Kilcoyne, Michelle; Puccia, Rosana

    2015-01-01

    Extracellular vesicles (EVs) mediate non-conventional transport of molecules across the fungal cell wall. We aimed at describing the carbohydrate composition and surface carbohydrate epitopes of EVs isolated from the pathogenic fungi Paracoccidioides brasiliensis and P. lutzii using standard procedures. Total EV carbohydrates were ethanol-precipitated from preparations depleted of lipids and proteins, then analyzed by chemical degradation, gas chromatography-mass spectrometry, nuclear magnetic resonance and size-exclusion chromatography. EV glycosyl residues of Glc, Man, and Gal comprised most probably two major components: a high molecular mass 4,6-α-glucan and a galactofuranosylmannan, possibly an oligomer, bearing a 2-α-Manp main chain linked to β-Galf (1,3) and α-Manp (1,6) end units. The results also suggested the presence of small amounts of a (1→6)-Manp polymer, (1→3)-glucan and (1→6)-glucan. Glycan microarrays allowed identification of EV surface lectin(s), while plant lectin microarray profiling revealed terminal Man and GlcNAc residues exposed at the EVs surface. Mammalian lectin microarray profiling showed that DC-SIGN receptors recognized surface carbohydrate in Paracoccidioides EVs. Our results suggest that oligosaccharides, cytoplasmic storage, and cell wall polysaccharides can be exported in fungal EVs, which also expose surface PAMPs and lectins. The role of these newly identified components in the interaction with the host remains to be unraveled. PMID:26387503

  3. Extracellular vesicles from Paracoccidioides pathogenic species transport polysaccharide and expose ligands for DC-SIGN receptors.

    PubMed

    Peres da Silva, Roberta; Heiss, Christian; Black, Ian; Azadi, Parastoo; Gerlach, Jared Q; Travassos, Luiz R; Joshi, Lokesh; Kilcoyne, Michelle; Puccia, Rosana

    2015-01-01

    Extracellular vesicles (EVs) mediate non-conventional transport of molecules across the fungal cell wall. We aimed at describing the carbohydrate composition and surface carbohydrate epitopes of EVs isolated from the pathogenic fungi Paracoccidioides brasiliensis and P. lutzii using standard procedures. Total EV carbohydrates were ethanol-precipitated from preparations depleted of lipids and proteins, then analyzed by chemical degradation, gas chromatography-mass spectrometry, nuclear magnetic resonance and size-exclusion chromatography. EV glycosyl residues of Glc, Man, and Gal comprised most probably two major components: a high molecular mass 4,6-?-glucan and a galactofuranosylmannan, possibly an oligomer, bearing a 2-?-Manp main chain linked to ?-Galf (1,3) and ?-Manp (1,6) end units. The results also suggested the presence of small amounts of a (1?6)-Manp polymer, (1?3)-glucan and (1?6)-glucan. Glycan microarrays allowed identification of EV surface lectin(s), while plant lectin microarray profiling revealed terminal Man and GlcNAc residues exposed at the EVs surface. Mammalian lectin microarray profiling showed that DC-SIGN receptors recognized surface carbohydrate in Paracoccidioides EVs. Our results suggest that oligosaccharides, cytoplasmic storage, and cell wall polysaccharides can be exported in fungal EVs, which also expose surface PAMPs and lectins. The role of these newly identified components in the interaction with the host remains to be unraveled. PMID:26387503

  4. Identification of New Antifungal Compounds Targeting Thioredoxin Reductase of Paracoccidioides Genus

    PubMed Central

    Abadio, Ana Karina Rodrigues; Kioshima, Erika Seki; Leroux, Vincent; Martins, Natalia Florêncio; Maigret, Bernard; Felipe, Maria Sueli Soares

    2015-01-01

    The prevalence of invasive fungal infections worldwide has increased in the last decades. The development of specific drugs targeting pathogenic fungi without producing collateral damage to mammalian cells is a daunting pharmacological challenge. Indeed, many of the toxicities and drug interactions observed with contemporary antifungal therapies can be attributed to “nonselective” interactions with enzymes or cell membrane systems found in mammalian host cells. A computer-aided screening strategy against the TRR1 protein of Paracoccidioides lutzii is presented here. Initially, a bank of commercially available compounds from Life Chemicals provider was docked to model by virtual screening simulations. The small molecules that interact with the model were ranked and, among the best hits, twelve compounds out of 3,000 commercially-available candidates were selected. These molecules were synthesized for validation and in vitro antifungal activity assays for Paracoccidioides lutzii and P. brasiliensis were performed. From 12 molecules tested, 3 harbor inhibitory activity in antifungal assays against the two pathogenic fungi. Corroborating these findings, the molecules have inhibitory activity against the purified recombinant enzyme TRR1 in biochemical assays. Therefore, a rational combination of molecular modeling simulations and virtual screening of new drugs has provided a cost-effective solution to an early-stage medicinal challenge. These results provide a promising technique to the development of new and innovative drugs. PMID:26569405

  5. Predicting copper-, iron-, and zinc-binding proteins in pathogenic species of the Paracoccidioides genus

    PubMed Central

    Tristão, Gabriel B.; Assunção, Leandro do Prado; dos Santos, Luiz Paulo A.; Borges, Clayton L.; Silva-Bailão, Mirelle Garcia; Soares, Célia M. de Almeida; Cavallaro, Gabriele; Bailão, Alexandre M.

    2015-01-01

    Approximately one-third of all proteins have been estimated to contain at least one metal cofactor, and these proteins are referred to as metalloproteins. These represent one of the most diverse classes of proteins, containing metal ions that bind to specific sites to perform catalytic, regulatory and structural functions. Bioinformatic tools have been developed to predict metalloproteins encoded by an organism based only on its genome sequence. Its function and the type of metal binder can also be predicted via a bioinformatics approach. Paracoccidioides complex includes termodimorphic pathogenic fungi that are found as saprobic mycelia in the environment and as yeast, the parasitic form, in host tissues. They are the etiologic agents of Paracoccidioidomycosis, a prevalent systemic mycosis in Latin America. Many metalloproteins are important for the virulence of several pathogenic microorganisms. Accordingly, the present work aimed to predict the copper, iron and zinc proteins encoded by the genomes of three phylogenetic species of Paracoccidioides (Pb01, Pb03, and Pb18). The metalloproteins were identified using bioinformatics approaches based on structure, annotation and domains. Cu-, Fe-, and Zn-binding proteins represent 7% of the total proteins encoded by Paracoccidioides spp. genomes. Zinc proteins were the most abundant metalloproteins, representing 5.7% of the fungus proteome, whereas copper and iron proteins represent 0.3 and 1.2%, respectively. Functional classification revealed that metalloproteins are related to many cellular processes. Furthermore, it was observed that many of these metalloproteins serve as virulence factors in the biology of the fungus. Thus, it is concluded that the Cu, Fe, and Zn metalloproteomes of the Paracoccidioides spp. are of the utmost importance for the biology and virulence of these particular human pathogens. PMID:25620964

  6. In silico characterization of hypothetical proteins from Paracoccidioides lutzii.

    PubMed

    Silva, P F F; Novaes, E; Pereira, M; Soares, C M A; Borges, C L; Salem-Izacc, S M

    2015-01-01

    Nearly 60% of Paracoccidioides lutzii genes encode products annotated as hypothetical or predicted proteins (HPs). In this study, we describe the global detection and functional inference of HPs, using computational methods based on sequence similarity, identification of targeting signals, presence of known protein domains, and use of the Gene Ontology functional classification scheme. Our analysis enabled a high-throughput characterization of predicted cellular localization and presence of protein domains, clustering HPs into different functional categories including metabolism, localization, cell cycle, response to stimulus, and signaling. To investigate P. lutzii HP expression profiles, we used data obtained from the expressed sequence tag database (dbEST). These analyses revealed 2364 HPs expressed in different situations, namely in mycelial and yeast forms, during the transition from mycelium to yeast, and under conditions mimicking infection. Based on this transcriptomic data, we performed a functional enrichment analysis according to the domains present in the HPs expressed in each condition. The most overrepresented functional domains were those involved in the regulation of gene expression, suggesting important and as yet undescribed roles for these HPs in the adaptation of P. lutzii to environmental conditions. In addition, the expression profiles of six randomly selected HPs were analyzed by quantitative real-time polymerase chain reaction in order to verify their expression in the complementary DNA libraries analyzed in this investigation. The approach used in this study should improve functional characterization of P. lutzii HPs. PMID:26782383

  7. Transcriptional profile of Paracoccidioides induced by oenothein B, a potential antifungal agent from the Brazilian Cerrado plant Eugenia uniflora

    PubMed Central

    2013-01-01

    Background The compound oenothein B (OenB), which is isolated from the leaves of Eugenia uniflora, a Brazilian Cerrado plant, interferes with Paracoccidioides yeast cell morphology and inhibits 1,3-β-D-glucan synthase (PbFKS1) transcript accumulation, which is involved in cell wall synthesis. In this work we examined the gene expression changes in Paracoccidioides yeast cells following OenB treatment in order to investigate the adaptive cellular responses to drug stress. Results We constructed differential gene expression libraries using Representational Difference Analysis (RDA) of Paracoccidioides yeast cells treated with OenB for 90 and 180 min. Treatment for 90 min resulted in the identification of 463 up-regulated expressed sequences tags (ESTs) and 104 down-regulated ESTs. For the 180 min treatment 301 up-regulated ESTs and 143 down-regulated were identified. Genes involved in the cell wall biosynthesis, such as GLN1, KRE6 and FKS1, were found to be regulated by OenB. Infection experiments in macrophages corroborated the in vitro results. Fluorescence microscopy showed increased levels of chitin in cells treated with OenB. The carbohydrate polymer content of the cell wall of the fungus was also evaluated, and the results corroborated with the transcriptional data. Several other genes, such as those involved in a variety of important cellular processes (i.e., membrane maintenance, stress and virulence) were found to be up-regulated in response to OenB treatment. Conclusions The exposure of Paracoccidioides to OenB resulted in a complex altered gene expression profile. Some of the changes may represent specific adaptive responses to this compound in this important pathogenic fungus. PMID:24119145

  8. Comparative proteomics in the genus Paracoccidioides.

    PubMed

    Pigosso, Laurine Lacerda; Parente, Ana Flávia Alves; Coelho, Alexandre Siqueira Guedes; Silva, Luciano Paulino; Borges, Clayton Luiz; Bailão, Alexandre Melo; Soares, Célia Maria de Almeida

    2013-11-01

    The genus Paracoccidioides comprises a complex of phylogenetic species of dimorphic pathogenic fungi, the etiologic agents of paracoccidioidomycosis (PCM), a disease confined to Latin America and of marked relevance in its endemic areas due to its high frequency and severity. The members of the Paracoccidioides genus are distributed in distinct phylogenetic species (S1, PS2, PS3 and 01-like) that potentially differ in their biochemical and molecular characteristics. In this work, we performed the proteomic characterization of different members of the genus Paracoccidioides. We compared the proteomic profiles of Pb01 (01-like), Pb2 (PS2), Pb339 (S1) and PbEPM83 (PS3) using 2D electrophoresis and mass spectrometry. The proteins/isoforms were selected based on the staining intensity of the spots as determined by image analysis. The proteins/isoforms were in-gel digested and identified by peptide mass fingerprinting and ion fragmentation. A total of 714 spots were detected, of which 343 were analyzed. From these spots, 301 represented differentially expressed proteins/isoforms among the four analyzed isolates, as determined by ANOVA. After applying the FDR correction, a total of 267 spots were determined to be differentially expressed. From the total, 193 proteins/isoforms were identified by PMF and confirmed by ion fragmentation. Comparing the expression profiles of the isolates, the proteins/isoforms that were related to glycolysis/gluconeogenesis and to alcohol fermentation were more abundant in Pb01 than in other representatives of the genus Paracoccidioides, indicating ahigher use of anaerobic pathways for energy production. Those enzymes related to the oxidative stress response were more abundant in Pb01, Pb2 and Pb339, indicating a better response to ROS in these members of the Paracoccidioides complex. The enzymes of the pentose phosphate pathway were abundant in Pb2. Antigenic proteins, such as GP43 and a 27-kDa antigenic protein, were less abundant in Pb01 and Pb2. The proteomic profile indicates metabolic differences among the analyzed members of the Paracoccidioides genus. PMID:23911955

  9. Inhibition of Paracoccidioides lutzii Pb01 Isocitrate Lyase by the Natural Compound Argentilactone and Its Semi-Synthetic Derivatives

    PubMed Central

    do Prado, Renata Silva; Alves, Ricardo Justino; de Oliveira, Cecília Maria Alves; Kato, Lucília; da Silva, Roosevelt Alves; Quintino, Guilherme Oliveira; do Desterro Cunha, Silvio; de Almeida Soares, Célia Maria; Pereira, Maristela

    2014-01-01

    The dimorphic fungus Paracoccidioides spp. is responsible for paracoccidioidomycosis, the most prevalent systemic mycosis in Latin America, causing serious public health problems. Adequate treatment of mycotic infections is difficult, since fungi are eukaryotic organisms with a structure and metabolism similar to those of eukaryotic hosts. In this way, specific fungus targets have become important to search of new antifungal compound. The role of the glyoxylate cycle and its enzymes in microbial virulence has been reported in many fungal pathogens, including Paracoccidioides spp. Here, we show the action of argentilactone and its semi-synthetic derivative reduced argentilactone on recombinant and native isocitrate lyase from Paracoccidioides lutzii Pb01 (PbICL) in the presence of different carbon sources, acetate and glucose. Additionally, argentilactone and its semi-synthetic derivative reduced argentilactone exhibited relevant inhibitory activity against P. lutzii Pb01 yeast cells and dose-dependently influenced the transition from the mycelium to yeast phase. The other oxygenated derivatives tested, epoxy argentilactone and diol argentilactone-, did not show inhibitory action on the fungus. The results were supported by in silico experiments. PMID:24752170

  10. Transcriptional profile of the human pathogenic fungus Paracoccidioides lutzii in response to sulfamethoxazole.

    PubMed

    Zambuzzi-Carvalho, Patrícia Fernanda; Fernandes, Amanda Gregorim; Valadares, Marize Campos; Tavares, Patrícia de Mello; Nosanchuk, Joshua D; Soares, Célia Maria de Almeida; Pereira, Maristela

    2015-06-01

    Paracoccidioidomycosis (PCM) is the most prevalent mycosis in Latin America and is caused by a group of fungi within the Paracoccidioides genus. The disease may present clinical and pathological manifestations ranging from asymptomatic pneumonia pulmonary lesions, to disseminated forms involving multiple organs. Sulfonamides were the first drugs used to treat PCM and are still used against this fungal infection. Sulfa drugs are competitive antagonists of ρ-aminobenzoic acid (PABA), a reaction catalyzed by dihydropteroate synthase (DHPS). However, the molecular effects of sulfonamides against the Paracoccidioides genus are unknown. The aim of this work was to investigate the global mechanism of action of sulfamethoxazole on Paracoccidioides lutzii. Yeast cells were grown on minimum medium in the presence or absence of sulfamethoxazole to construct EST libraries. The representational difference analysis (RDA) technique was used to identify up- and down-regulated P. lutzii genes after treatment with sulfamethoxazole. Approximately six transcripts related to mitochondrial function were differentially expressed. To confirm the RDA and bioinformatics results, several relevant genes were studied with quantitative real-time polymerase chain reaction (qRT-PCR) to evaluate their levels of expression. To confirm the impact of sulfamethoxazole on mitochondria, we measured the reduction of tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) by P. lutzii with or without exposure to the drug. MTT assays reveal that sulfamethoxazole produces a marked dose-dependent adverse effect on P. lutzii. The transcriptional activity of selected genes in infected macrophages corroborated our in vitro results. The results indicated that sulfamethoxazole acts in P. lutzii as a competitor for amino acid, nucleic acids and folate cofactor biosynthesis, disrupting mitochondrial functions. PMID:25850856

  11. Factors associated with Paracoccidiodes brasiliensis infection among permanent residents of three endemic areas in Colombia.

    PubMed Central

    Cadavid, D.; Restrepo, A.

    1993-01-01

    The natural habitat of Paracoccidioides brasiliensis, the aetiologic agent of paracoccidioidomycosis, has not been determined. Consequently, the events leading to the acquisition of infection remain controversial. To identify factors associated with infection in endemic areas we conducted a survey in three rural communities in Colombia where we had previously diagnosed paracoccidioidomycosis in children. Permanent residents were surveyed taking into consideration environmental and occupational variables. Skin tests were used to classify subjects as infected or non-infected. Variables found associated with infection were: (i) community A: previous residence around Porce river and agriculture in vegetable gardens; (ii) community C: frequent use of specific water sources; (iii) community V: housekeeping activities, and (iv) total group: age > 25 years and contact with bats. Residents in communities with higher prevalence of infection were older, had more complex residence history, and referred more contact with armadillos than residents of communities with lower infection. PMID:8348926

  12. Dendritic cell interactions with Histoplasma and Paracoccidioides.

    PubMed

    Thind, Sharanjeet K; Taborda, Carlos P; Nosanchuk, Joshua D

    2015-01-01

    Fungi are among the most common microbes encountered by humans. More than 100, 000 fungal species have been described in the environment to date, however only a few species cause disease in humans. Fungal infections are of particular importance to immunocompromised hosts in whom disease is often more severe, especially in those with impaired cell-mediated immunity such as individuals with HIV infection, hematologic malignancies, or those receiving TNF-α inhibitors. Nevertheless, environmental disturbances through natural processes or as a consequence of deforestation or construction can expose immunologically competent people to a large number of fungal spores resulting in asymptomatic acquisition to life-threatening disease. In recent decades, the significance of the innate immune system and more importantly the role of dendritic cells (DC) have been found to play a fundamental role in the resolution of fungal infections, such as in dimorphic fungi like Histoplasma and Paracoccidioides. In this review article the general role of DCs will be illustrated as the bridge between the innate and adaptive immune systems, as well as their specific interactions with these 2 dimorphic fungi. PMID:25933034

  13. Hemoglobin Uptake by Paracoccidioides spp. Is Receptor-Mediated

    PubMed Central

    Bailão, Elisa Flávia Luiz Cardoso; Parente, Juliana Alves; Pigosso, Laurine Lacerda; de Castro, Kelly Pacheco; Fonseca, Fernanda Lopes; Silva-Bailão, Mirelle Garcia; Báo, Sônia Nair; Bailão, Alexandre Melo; Rodrigues, Marcio L.; Hernandez, Orville; McEwen, Juan G.; Soares, Célia Maria de Almeida

    2014-01-01

    Iron is essential for the proliferation of fungal pathogens during infection. The availability of iron is limited due to its association with host proteins. Fungal pathogens have evolved different mechanisms to acquire iron from host; however, little is known regarding how Paracoccidioides species incorporate and metabolize this ion. In this work, host iron sources that are used by Paracoccidioides spp. were investigated. Robust fungal growth in the presence of the iron-containing molecules hemin and hemoglobin was observed. Paracoccidioides spp. present hemolytic activity and have the ability to internalize a protoporphyrin ring. Using real-time PCR and nanoUPLC-MSE proteomic approaches, fungal growth in the presence of hemoglobin was shown to result in the positive regulation of transcripts that encode putative hemoglobin receptors, in addition to the induction of proteins that are required for amino acid metabolism and vacuolar protein degradation. In fact, one hemoglobin receptor ortholog, Rbt5, was identified as a surface GPI-anchored protein that recognized hemin, protoporphyrin and hemoglobin in vitro. Antisense RNA technology and Agrobacterium tumefaciens-mediated transformation were used to generate mitotically stable Pbrbt5 mutants. The knockdown strain had a lower survival inside macrophages and in mouse spleen when compared with the parental strain, which suggested that Rbt5 could act as a virulence factor. In summary, our data indicate that Paracoccidioides spp. can use hemoglobin as an iron source most likely through receptor-mediated pathways that might be relevant for pathogenic mechanisms. PMID:24831516

  14. Transcriptional and Proteomic Responses to Carbon Starvation in Paracoccidioides

    PubMed Central

    Lima, Patrícia de Sousa; Casaletti, Luciana; Bailão, Alexandre Melo; de Vasconcelos, Ana Tereza Ribeiro; Fernandes, Gabriel da Rocha; Soares, Célia Maria de Almeida

    2014-01-01

    Background The genus Paracoccidioides comprises human thermal dimorphic fungi, which cause paracoccidioidomycosis (PCM), an important mycosis in Latin America. Adaptation to environmental conditions is key to fungal survival during human host infection. The adaptability of carbon metabolism is a vital fitness attribute during pathogenesis. Methodology/Principal Findings The fungal pathogen Paracoccidioides spp. is exposed to numerous adverse conditions, such as nutrient deprivation, in the human host. In this study, a comprehensive response of Paracoccidioides, Pb01, under carbon starvation was investigated using high-resolution transcriptomic (RNAseq) and proteomic (NanoUPLC-MSE) approaches. A total of 1,063 transcripts and 421 proteins were differentially regulated, providing a global view of metabolic reprogramming during carbon starvation. The main changes were those related to cells shifting to gluconeogenesis and ethanol production, supported by the degradation of amino acids and fatty acids and by the modulation of the glyoxylate and tricarboxylic cycles. This proposed carbon flow hypothesis was supported by gene and protein expression profiles assessed using qRT-PCR and western blot analysis, respectively, as well as using enzymatic, cell dry weight and fungus-macrophage interaction assays. The carbon source provides a survival advantage to Paracoccidioides inside macrophages. Conclusions/Significance For a complete understanding of the physiological processes in an organism, the integration of approaches addressing different levels of regulation is important. To the best of our knowledge, this report presents the first description of the responses of Paracoccidioides spp. to host-like conditions using large-scale expression approaches. The alternative metabolic pathways that could be adopted by the organism during carbon starvation can be important for a better understanding of the fungal adaptation to the host, because systems for detecting and responding to carbon sources play a major role in adaptation and persistence in the host niche. PMID:24811072

  15. Mitochondrial PCR-RFLP Assay to Distinguish Triatoma brasiliensis macromelasoma from Triatoma brasiliensis brasiliensis Subspecies (Hemiptera: Reduviidae)

    PubMed Central

    Ceretti-Junior, Walter; Obara, Marcos Takashi; Marrelli, Mauro Toledo

    2013-01-01

    Triatoma brasiliensis sensu lato (s.l.), the main vector of Chagas disease in northeastern Brazil, is a species complex comprising four species, one with two subspecies (T. brasiliensis brasiliensis, T. brasiliensis macromelasoma, T. juazeirensis, T. sherlocki, and T. melanica), and each taxon displaying distinct ecological requirements. In order to evaluate the genetic relationships among nine T. brasiliensis s.l. populations from northeastern Brazil, we analyzed their mitochondrial cytochrome c oxidase subunit 1 sequences and suggested a PCR-RFLP assay to distinguish between T. b. macromelasoma and T. b. brasiliensis subspecies. All the specimens were morphologically identified as T. b. brasiliensis. The resulting phylogenies identified two major clades that are congruent with the geographical populations studied. Based on collection sites and in accordance with type-location, one clade was identified as the subspecies T. b. macromelasoma. The second clade grouped T. b. brasiliensis populations. Restriction endonuclease sites were observed in the sequences and used in PCR-RFLP assays, producing distinct fingerprints for T. b. macromelasoma and T. b. brasiliensis populations. The results suggest that these are different species and that gene flow occurs only among T. b. brasiliensis populations, possibly associated with human activity in the area. PMID:24454408

  16. Proteomic profile response of Paracoccidioides lutzii to the antifungal argentilactone

    PubMed Central

    Prado, Renata S.; Bailão, Alexandre M.; Silva, Lívia C.; de Oliveira, Cecília M. A.; Marques, Monique F.; Silva, Luciano P.; Silveira-Lacerda, Elisângela P.; Lima, Aliny P.; Soares, Célia M.; Pereira, Maristela

    2015-01-01

    The dimorphic fungi Paracoccidioides spp. are the etiological agents of paracoccidioidomycosis (PCM), a mycosis of high incidence in Brazil. The toxicity of drug treatment and the emergence of resistant organisms have led to research for new candidates for drugs. In this study, we demonstrate that the natural product argentilactone was not cytotoxic or genotoxic to MRC5 cells at the IC50 concentration to the fungus. We also verified the proteomic profile of Paracoccidioides lutzii after incubation with argentilactone using a label free quantitative proteome nanoUPLC-MSE. The results of this study indicated that the fungus has a global metabolic adaptation in the presence of argentilactone. Enzymes of important pathways, such as glycolysis, the Krebs cycle and the glyoxylate cycle, were repressed, which drove the metabolism to the methylcytrate cycle and beta-oxidation. Proteins involved in cell rescue, defense and stress response were induced. In this study, alternative metabolic pathways adopted by the fungi were elucidated, helping to elucidate the course of action of the compound studied. PMID:26150808

  17. Cloning and characterisation of JAZ gene family in Hevea brasiliensis.

    PubMed

    Hong, H; Xiao, H; Yuan, H; Zhai, J; Huang, X

    2015-05-01

    Mechanical wounding or treatment with exogenous jasmonates (JA) induces differentiation of the laticifer in Hevea brasiliensis. JA is a key signal for latex biosynthesis and wounding response in the rubber tree. Identification of JAZ (jasmonate ZIM-domain) family of proteins that repress JA responses has facilitated rapid progress in understanding how this lipid-derived hormone controls gene expression and related physiological processes in plants. In this work, the full-length cDNAs of six JAZ genes were cloned from H. brasiliensis (termed HbJAZ). These HbJAZ have different lengths and sequence diversity, but all of them contain Jas and ZIM domains, and two of them contain an ERF-associated amphiphilic repression (EAR) motif in the N-terminal. Real-time RT-PCR analyses revealed that HbJAZ have different expression patterns and tissue specificity. Four HbJAZ were up-regulated, one was down-regulated, while two were less effected by rubber tapping treatment, suggesting that they might play distinct roles in the wounding response. A yeast two-hybrid assay revealed that HbJAZ proteins interact with each other to form homologous or heterogeneous dimer complexes, indicating that the HbJAZ proteins may expand their function through diverse JAZ-JAZ interactions. This work lays a foundation for identification of the JA signalling pathway and molecular mechanisms of latex biosynthesis in rubber trees. PMID:25399518

  18. Paracoccidoides brasiliensis 30 kDa Adhesin: Identification as a 14-3-3 Protein, Cloning and Subcellular Localization in Infection Models

    PubMed Central

    da Silva, Julhiany de Fatima; de Oliveira, Haroldo César; Marcos, Caroline Maria; da Silva, Rosângela Aparecida Moraes; da Costa, Tania Alves; Calich, Vera Lucia García; Almeida, Ana Marisa Fusco; Mendes-Giannini, Maria José Soares

    2013-01-01

    Paracoccidoides brasiliensis adhesion to lung epithelial cells is considered an essential event for the establishment of infection and different proteins participate in this process. One of these proteins is a 30 kDa adhesin, pI 4.9 that was described as a laminin ligand in previous studies, and it was more highly expressed in more virulent P. brasiliensis isolates. This protein may contribute to the virulence of this important fungal pathogen. Using Edman degradation and mass spectrometry analysis, this 30 kDa adhesin was identified as a 14-3-3 protein. These proteins are a conserved group of small acidic proteins involved in a variety of processes in eukaryotic organisms. However, the exact function of these proteins in some processes remains unknown. Thus, the goal of the present study was to characterize the role of this protein during the interaction between the fungus and its host. To achieve this goal, we cloned, expressed the 14-3-3 protein in a heterologous system and determined its subcellular localization in in vitro and in vivo infection models. Immunocytochemical analysis revealed the ubiquitous distribution of this protein in the yeast form of P. brasiliensis, with some concentration in the cytoplasm. Additionally, this 14-3-3 protein was also present in P. brasiliensis cells at the sites of infection in C57BL/6 mice intratracheally infected with P. brasiliensis yeast cells for 72 h (acute infections) and 30 days (chronic infection). An apparent increase in the levels of the 14-3-3 protein in the cell wall of the fungus was also noted during the interaction between P. brasiliensis and A549 cells, suggesting that this protein may be involved in host-parasite interactions, since inhibition assays with the protein and this antibody decreased P. brasiliensis adhesion to A549 epithelial cells. Our data may lead to a better understanding of P. brasiliensis interactions with host tissues and paracoccidioidomycosis pathogenesis. PMID:23638109

  19. Hydroxamate Production as a High Affinity Iron Acquisition Mechanism in Paracoccidioides Spp

    PubMed Central

    Silva-Bailão, Mirelle Garcia; Bailão, Elisa Flávia Luiz Cardoso; Lechner, Beatrix Elisabeth; Gauthier, Gregory M.; Lindner, Herbert; Bailão, Alexandre Melo; Haas, Hubertus; de Almeida Soares, Célia Maria

    2014-01-01

    Iron is a micronutrient required by almost all living organisms, including fungi. Although this metal is abundant, its bioavailability is low either in aerobic environments or within mammalian hosts. As a consequence, pathogenic microorganisms evolved high affinity iron acquisition mechanisms which include the production and uptake of siderophores. Here we investigated the utilization of these molecules by species of the Paracoccidioides genus, the causative agents of a systemic mycosis. It was demonstrated that iron starvation induces the expression of Paracoccidioides ortholog genes for siderophore biosynthesis and transport. Reversed-phase HPLC analysis revealed that the fungus produces and secretes coprogen B, which generates dimerumic acid as a breakdown product. Ferricrocin and ferrichrome C were detected in Paracoccidioides as the intracellular produced siderophores. Moreover, the fungus is also able to grow in presence of siderophores as the only iron sources, demonstrating that beyond producing, Paracoccidioides is also able to utilize siderophores for growth, including the xenosiderophore ferrioxamine. Exposure to exogenous ferrioxamine and dimerumic acid increased fungus survival during co-cultivation with macrophages indicating that these molecules play a role during host-pathogen interaction. Furthermore, cross-feeding experiments revealed that Paracoccidioides siderophores promotes growth of Aspergillus nidulans strain unable to produce these iron chelators. Together, these data denote that synthesis and utilization of siderophores is a mechanism used by Paracoccidioides to surpass iron limitation. As iron paucity is found within the host, siderophore production may be related to fungus pathogenicity. PMID:25157575

  20. Lipoxin Inhibits Fungal Uptake by Macrophages and Reduces the Severity of Acute Pulmonary Infection Caused by Paracoccidioides brasiliensis

    PubMed Central

    Ribeiro, Laura R. R.; Loures, Flávio V.; de Araújo, Eliseu F.; Feriotti, Cláudia; Costa, Tânia A.; Serezani, Carlos Henrique; Jancar, Sonia; Calich, Vera L. G.

    2015-01-01

    Cysteinyl leukotrienes (CysLTs) and lipoxins (LXs) are lipid mediators that control inflammation, with the former inducing and the latter inhibiting this process. Because the role played by these mediators in paracoccidioidomycosis was not investigated, we aimed to characterize the role of CysLT in the pulmonary infection developed by resistant (A/J) and susceptible (B10.A) mice. 48 h after infection, elevated levels of pulmonary LTC4 and LXA4 were produced by both mouse strains, but higher levels were found in the lungs of susceptible mice. Blocking the CysLTs receptor by MTL reduced fungal loads in B10.A, but not in A/J mice. In susceptible mice, MLT treatment led to reduced influx of PMN leukocytes, increased recruitment of monocytes, predominant synthesis of anti-inflammatory cytokines, and augmented expression of 5- and 15-lipoxygenase mRNA, suggesting a prevalent LXA4 activity. In agreement, MTL-treated macrophages showed reduced fungal burdens associated with decreased ingestion of fungal cells. Furthermore, the addition of exogenous LX reduced, and the specific blockade of the LX receptor increased the fungal loads of B10.A macrophages. This study showed for the first time that inhibition of CysLTs signaling results in less severe pulmonary paracoccidioidomycosis that occurs in parallel with elevated LX activity and reduced infection of macrophages. PMID:26635449

  1. Hydroxynitrile lyase from Hevea brasiliensis: molecular characterization and mechanism of enzyme catalysis.

    PubMed

    Hasslacher, M; Kratky, C; Griengl, H; Schwab, H; Kohlwein, S D

    1997-03-01

    (S)-Hydroxynitrile lyase (Hnl) from the tropical rubber tree Hevea brasiliensis is a 29 kDa single chain protein that catalyses the breakdown or formation of a C--C bond by reversible addition of hydrocyanic acid to aldehydes or ketones. The primary sequence of Hnl has no significant homology to known proteins. Detailed homology investigations employing PROFILESEARCH and secondary structure prediction algorithms suggest that Hnl is a member of the alpha/beta hydrolase fold protein family and contains a catalytic triad as functional residues for catalysis. The significance of predicted catalytic residues was tested and confirmed by site-directed mutagenesis and expression of mutant and wild-type proteins in the yeast, Saccharomyces cerevisiae. Based on these data we suggest a mechanistic model for the (S)-cyanohydrin synthesis catalyzed by hydroxynitrile lyase from Hevea brasiliensis. PMID:9094745

  2. Nocardia brasiliensis vertebral osteomyelitis and epidural abscess.

    PubMed

    Johnson, Philip; Ammar, Hussam

    2013-01-01

    Nocardia species exist in the environment as a saprophyte; it is found worldwide in soil and decaying plant matter. They often infect patients with underlying immune compromise, pulmonary disease or history of trauma or surgery. The diagnosis of nocardiosis can be easily missed as it mimics many other granulomatous and neoplastic disease. We report a 69-year-old man who presented with chronic back pain and paraparesis. He was found to have Nocardial brasiliensis vertebral osteomyelitis and epidural abscess. Laminectomy and epidural wash out was performed but with no neurological recovery. This is the second reported case of N brasiliensis vertebral osteomyelitis in the literature. PMID:23585503

  3. Nocardia brasiliensis vertebral osteomyelitis and epidural abscess

    PubMed Central

    Johnson, Philip; Ammar, Hussam

    2013-01-01

    Nocardia species exist in the environment as a saprophyte; it is found worldwide in soil and decaying plant matter. They often infect patients with underlying immune compromise, pulmonary disease or history of trauma or surgery. The diagnosis of nocardiosis can be easily missed as it mimics many other granulomatous and neoplastic disease. We report a 69-year-old man who presented with chronic back pain and paraparesis. He was found to have Nocardial brasiliensis vertebral osteomyelitis and epidural abscess. Laminectomy and epidural wash out was performed but with no neurological recovery. This is the second reported case of N brasiliensis vertebral osteomyelitis in the literature. PMID:23585503

  4. Paracoccidioides spp. ferrous and ferric iron assimilation pathways

    PubMed Central

    Bailão, Elisa Flávia L. C.; Lima, Patrícia de Sousa; Silva-Bailão, Mirelle G.; Bailão, Alexandre M.; Fernandes, Gabriel da Rocha; Kosman, Daniel J.; Soares, Célia Maria de Almeida

    2015-01-01

    Iron is an essential micronutrient for almost all organisms, including fungi. Usually, fungi can uptake iron through receptor-mediated internalization of a siderophore or heme, and/or reductive iron assimilation (RIA). Traditionally, the RIA pathway consists of ferric reductases (Fres), ferroxidase (Fet3) and a high-affinity iron permease (Ftr1). Paracoccidioides spp. genomes do not present an Ftr1 homolog. However, this fungus expresses zinc regulated transporter homologs (Zrts), members of the ZIP family of membrane transporters that are able in some organisms to transport zinc and iron. A 2,3,5-triphenyltetrazolium chloride (TTC)-overlay assay indicates that both Pb01 and Pb18 express a ferric reductase activity; however, 59Fe uptake assays indicate that only in Pb18 is this activity coupled to a reductase-dependent iron uptake pathway. In addition, Zrts are up-regulated in iron deprivation, as indicated by RNAseq and qRT-PCR using Pb01 transcripts. RNAseq strategy also demonstrated that transcripts related to siderophore uptake and biosynthesis are up-regulated in iron-deprived condition. The data suggest that the fungus could use both a non-classical RIA, comprising ferric reductases and Fe/Zn permeases (Zrts), and siderophore uptake pathways under iron-limited conditions. The study of iron metabolism reveals novel surface molecules that could function as accessible targets for drugs to block iron uptake and, consequently, inhibit pathogen's proliferation. PMID:26441843

  5. Nocardia brasiliensis-associated femorotibial osteomyelitis.

    PubMed

    Vanegas, Samuel; Franco-Cendejas, Rafael; Cicero, Antonio; López-Jácome, Esaú; Colin, Claudia; Hernández, Melissa

    2014-03-01

    We report a case of femorotibial osteomyelitis due to Nocardia brasiliensis. Nocardia spp are a rare cause of bone infections, and the majority of such cases are associated with the spine. This type of osteomyelitis is uncommon, and in the immunocompetent host, is more often related to a chronic evolution following direct inoculation of the microorganism. PMID:24362018

  6. Yeast Infections

    MedlinePLUS

    ... taking antibiotics, it can multiply and cause an infection. Yeast infections affect different parts of the body in different ways: Thrush is a yeast infection that causes white patches in your mouth Candida ...

  7. Yeast Infection

    MedlinePLUS

    ... majority of vaginal yeast infections are caused by Candida Albicans ? There are some less common yeast organisms such as Torulopsis Glabrata that may cause infections that do not clear up with the ...

  8. Miltefosine is active against Sporothrix brasiliensis isolates with in vitro low susceptibility to amphotericin B or itraconazole.

    PubMed

    Borba-Santos, Luana Pereira; Gagini, Thalita; Ishida, Kelly; de Souza, Wanderley; Rozental, Sonia

    2015-04-01

    Sporotrichosis is a common mycosis caused by dimorphic fungi from the Sporothrix schenckii complex. In recent years, sporotrichosis incidence rates have increased in the Brazilian state of Rio de Janeiro, where Sporothrix brasiliensis is the species more frequently isolated from patients. The standard antifungals itraconazole and amphotericin B are recommended as first-line therapy for cutaneous/lymphocutaneous and disseminated sporotrichosis, respectively, although decreased sensitivity to these drugs in vitro was reported for clinical isolates of S. brasiliensis. Here, we evaluated the activity of the phospholipid analogue miltefosine - already in clinical use against leishmaniasis - towards the pathogenic yeast form of S. brasiliensis isolates with low sensitivity to itraconazole or amphotericin B in vitro. Miltefosine had fungicidal activity, with minimum inhibitory concentration (MIC) values of 1-2 µg ml(-1). Miltefosine exposure led to loss of plasma membrane integrity, and transmission electron microscopy (TEM) analysis revealed a decrease in cytoplasmic electron density, alterations in the thickness of cell wall layers and accumulation of an electron-dense material in the cell wall. Flow cytometry analysis using an anti-melanin antibody revealed an increase in cell wall melanin in yeasts treated with miltefosine, when compared with control cells. The cytotoxicity of miltefosine was comparable to those of amphotericin B, but miltefosine showed a higher selectivity index towards the fungus. Our results suggest that miltefosine could be an effective alternative for the treatment of S. brasiliensis sporotrichosis, when standard treatment fails. Nevertheless, in vivo studies are required to confirm the antifungal potential of miltefosine for the treatment of sporotrichosis. PMID:25681323

  9. Complete genome sequence of Nocardia brasiliensis HUJEG-1.

    PubMed

    Vera-Cabrera, Lucio; Ortiz-Lopez, Rocio; Elizondo-Gonzalez, Ramiro; Perez-Maya, Antonio Ali; Ocampo-Candiani, Jorge

    2012-05-01

    In Mexico, actinomycetoma is mainly caused by Nocardia brasiliensis, which is a soil inhabitant actinobacterium. Here, we report for the first time the draft genome of a strain isolated from a human case that has largely been found in in vitro and experimental models of actinomycetoma, N. brasiliensis HUJEG-1. PMID:22535940

  10. Genetic Diversity of Pectobacterium carotovorum subsp. brasiliensis Isolated in Korea

    PubMed Central

    Lee, Dong Hwan; Kim, Jin-Beom; Lim, Jeong-A; Han, Sang-Wook; Heu, Sunggi

    2014-01-01

    The plant pathogenic bacterial genus Pectobacteirum consists of heterogeneous strains. The P. carotovorum species is a complex strain showing divergent characteristics, and a new subspecies named P. carotovorum subsp. brasiliensis has been identified recently. In this paper, we re-identified the P. carotovorum subsp. brasiliensis isolates from those classified under the subspecies carotovorum and newly isolated P. carotovorum subsp. brasiliensis strains. All isolates were able to produce plant cell-wall degrading enzymes such as pectate lyase, polygalacturonase, cellulase and protease. We used genetic and biochemical methods to examine the diversity of P. carotovorum subsp. brasiliensis isolates, and found genetic diversity within the brasiliensis subsp. isolates in Korea. The restriction fragment length polymorphism analysis based on the recA gene revealed a unique pattern for the brasiliensis subspecies. The Korean brasiliensis subsp. isolates were divided into four clades based on pulsed-field gel electrophoresis. However, correlations between clades and isolated hosts or year could not be found, suggesting that diverse brasiliensis subsp. isolates existed. PMID:25288994

  11. The multifaceted roles of metabolic enzymes in the Paracoccidioides species complex

    PubMed Central

    Marcos, Caroline M.; de Oliveira, Haroldo C.; da Silva, Julhiany de F.; Assato, Patrícia A.; Fusco-Almeida, Ana M.; Mendes-Giannini, Maria J. S.

    2014-01-01

    Paracoccidioides species are dimorphic fungi and are the etiologic agents of paracoccidioidomycosis, which is a serious disease that involves multiple organs. The many tissues colonized by this fungus suggest a variety of surface molecules involved in adhesion. A surprising finding is that most enzymes in the glycolytic pathway, tricarboxylic acid (TCA) cycle and glyoxylate cycle in Paracoccidioides spp. have adhesive properties that aid in interacting with the host extracellular matrix and thus act as ‘moonlighting’ proteins. Moonlighting proteins have multiple functions, which adds a dimension to cellular complexity and benefit cells in several ways. This phenomenon occurs in both eukaryotes and prokaryotes. For example, moonlighting proteins from the glycolytic pathway or TCA cycle can play a role in bacterial pathogenesis by either acting as proteins secreted in a conventional pathway and/or as cell surface components that facilitate adhesion or adherence. This review outlines the multifunctionality exhibited by many Paracoccidioides spp. enzymes, including aconitase, aldolase, glyceraldehyde-3-phosphate dehydrogenase, isocitrate lyase, malate synthase, triose phosphate isomerase, fumarase, and enolase. We discuss the roles that moonlighting activities play in the virulence characteristics of this fungus and several other human pathogens during their interactions with the host. PMID:25566229

  12. Analysis of Sporothrix schenckii sensu stricto and Sporothrix brasiliensis virulence in Galleria mellonella.

    PubMed

    Clavijo-Giraldo, Diana M; Matínez-Alvarez, José A; Lopes-Bezerra, Leila M; Ponce-Noyola, Patricia; Franco, Bernardo; Almeida, Ricardo S; Mora-Montes, Héctor M

    2016-03-01

    The study of the host-pathogen interaction is essential to understand the mechanisms underlying adhesion, colonization and tissue damage by pathogens. This is usually achieved by performing in vivo studies using small mammals, such as rats, mice and guinea pigs. Nowadays, the mouse models of systemic or subcutaneous infection are the gold standard assays to analyze the virulence of members of the Sporothrix schenckii complex. There are, however, invertebrates that have been recently used as alternative hosts to assess the virulence of both bacteria and fungi, and among them, larvae of Galleria mellonella are popular because they are easy to breed, and require non-specialized facilities to maintain the colony. Here, we assessed the use of G. mellonella larvae to test the virulence of S. schenckii sensu stricto and Sporothrix brasiliensis strains, and found that infection with yeast-like cells, but not with conidia or germlings, reproduces the virulence data generated in the mouse model of infection. Furthermore, with this insect model we could classify the virulence of some strains as low, intermediate or high, in line with the observations in the mammalian model. Therefore, G. mellonella is suitable, and a new alternative, to test virulence of both S. schenckii sensu stricto and S. brasiliensis. PMID:26826293

  13. Identification and characterization of MAGO and Y14 genes in Hevea brasiliensis.

    PubMed

    Yang, Zi-Ping; Li, Hui-Liang; Guo, Dong; Peng, Shi-Qing

    2016-03-01

    Mago nashi (MAGO) and Y14 proteins are highly conserved among eukaryotes. In this study, we identified two MAGO (designated as HbMAGO1 andHbMAGO2) and two Y14 (designated as HbY14aand HbY14b) genes in the rubber tree (Hevea brasiliensis) genome annotation. Multiple amino acid sequence alignments predicted that HbMAGO and HbY14 proteins are structurally similar to homologous proteins from other species. Tissue-specific expression profiles showed that HbMAGO and HbY14 genes were expressed in at least one of the tissues (bark, flower, latex, leaf and root) examined. HbMAGOs and HbY14s were predominately located in the nucleus and were found to interact in yeast two-hybrid analysis (YTH) and bimolecular fluorescence complementation (BiFC) assays. HbMAGOs and HbY14s showed the highest transcription in latex and were regulated by ethylene and jasmonate. Interaction between HbMAGO2 and gp91phox (a large subunit of nicotinamide adenine dinucleotide phosphate) was identified using YTH and BiFC assays. These findings suggested that HbMAGO may be involved in the aggregation of rubber particles in H. brasiliensis. PMID:27007901

  14. Glycolipid composition of Hevea brasiliensis latex.

    PubMed

    Liengprayoon, Siriluck; Sriroth, Klanarong; Dubreucq, Eric; Vaysse, Laurent

    2011-10-01

    Glycolipids of fresh latex from three clones of Hevea brasiliensis were characterized and quantified by HPLC/ESI-MS. Their fatty acyl and sterol components were further confirmed by GC/MS after saponification. The four detected glycolipid classes were steryl glucosides (SG), esterified steryl glucosides (ESG), monogalactosyl diacylglycerols (MGDG) and digalactosyl diacylglycerols (DGDG). Sterols in SG, ESG and total latex unsaponifiable were stigmasterol, ?-sitosterol and ??-avenasterol. The latter was found instead of fucosterol formerly described. Galactolipids were mainly DGDG and had a fatty acid composition different from that of plant leaves as they contained less than 5% C18:3. Glycolipids, which represented 27-37% of total lipids, displayed important clonal variations in the proportions of the different fatty acids. ESG, MGDG and DGDG from clone PB235 differed notably by their higher content in furan fatty acid, which accounted for more than 40% of total fatty acids. Clonal variation was also observed in the relative proportions of glycolipid classes except MGDG (8%), with 43-51% DGDG, 30-34% SG and 7-19% ESG. When compared with other plant cell content, the unusual glycolipid composition of H. brasiliensis latex may be linked to the peculiar nature of this specialized cytoplasm expelled from laticiferous system, especially in terms of functional and structural properties. PMID:21605880

  15. Characterization of the Paracoccidioides Hypoxia Response Reveals New Insights into Pathogenesis Mechanisms of This Important Human Pathogenic Fungus

    PubMed Central

    Lima, Patrícia de Sousa; Chung, Dawoon; Bailão, Alexandre Melo; Cramer, Robert A.; Soares, Célia Maria de Almeida

    2015-01-01

    Background Hypoxic microenvironments are generated during fungal infection. It has been described that to survive in the human host, fungi must also tolerate and overcome in vivo microenvironmental stress conditions including low oxygen tension; however nothing is known how Paracoccidioides species respond to hypoxia. The genus Paracoccidioides comprises human thermal dimorphic fungi and are causative agents of paracoccidioidomycosis (PCM), an important mycosis in Latin America. Methodology/Principal Findings In this work, a detailed hypoxia characterization was performed in Paracoccidioides. Using NanoUPLC-MSE proteomic approach, we obtained a total of 288 proteins differentially regulated in 12 and 24 h of hypoxia, providing a global view of metabolic changes during this stress. In addition, a functional characterization of the homologue to the most important molecule involved in hypoxia responses in other fungi, the SREBP (sterol regulatory element binding protein) was performed. We observed that Paracoccidioides species have a functional homologue of SREBP, named here as SrbA, detected by using a heterologous genetic approach in the srbA null mutant in Aspergillus fumigatus. Paracoccidioides srbA (PbsrbA), in addition to involvement in hypoxia, is probable involved in iron adaptation and azole drug resistance responses. Conclusions/Significance In this study, the hypoxia was characterized in Paracoccidioides. The first results can be important for a better understanding of the fungal adaptation to the host and improve the arsenal of molecules for the development of alternative treatment options in future, since molecules related to fungal adaptation to low oxygen levels are important to virulence and pathogenesis in human pathogenic fungi. PMID:26659387

  16. Red yeast

    MedlinePLUS

    ... cholesterol levels and triglycerides. However, this specific product contains large amounts of a chemical similar to "statin" ... this product and other red yeast products that contain statins to be illegal unapproved drugs. However, outside ...

  17. Counting Yeast.

    ERIC Educational Resources Information Center

    Bealer, Jonathan; Welton, Briana

    1998-01-01

    Describes changes to a traditional study of population in yeast colonies. Changes to the procedures include: (1) only one culture per student team; (2) cultures are inoculated only once; and (3) the same tube is sampled daily. (DDR)

  18. Effects of Argentilactone on the Transcriptional Profile, Cell Wall and Oxidative Stress of Paracoccidioides spp.

    PubMed Central

    Araújo, Felipe Souto; Coelho, Luciene Melo; Silva, Lívia do Carmo; da Silva Neto, Benedito Rodrigues; Parente-Rocha, Juliana Alves; Bailão, Alexandre Melo; de Oliveira, Cecília Maria Alves; Fernandes, Gabriel da Rocha; Hernández, Orville; Ochoa, Juan Guillermo McEwen; Soares, Célia Maria de Almeida; Pereira, Maristela

    2016-01-01

    Paracoccidioides spp., a dimorphic pathogenic fungus, is the etiologic agent of paracoccidioidomycosis (PCM). PCM is an endemic disease that affects at least 10 million people in Latin America, causing severe public health problems. The drugs used against pathogenic fungi have various side effects and limited efficacy; therefore, there is an inevitable and urgent medical need for the development of new antifungal drugs. In the present study, we evaluated the transcriptional profile of Paracoccidioides lutzii exposed to argentilactone, a constituent of the essential oil of Hyptis ovalifolia. A total of 1,058 genes were identified, of which 208 were up-regulated and 850 were down-regulated. Cell rescue, defense and virulence, with a total of 26 genes, was a functional category with a large number of genes induced, including heat shock protein 90 (hsp90), cytochrome c peroxidase (ccp), the hemoglobin ligand RBT5 (rbt5) and superoxide dismutase (sod). Quantitative real-time PCR revealed an increase in the expression level of all of those genes. An enzymatic assay showed a significant increase in SOD activity. The reduced growth of Pbhsp90-aRNA, Pbccp-aRNA, Pbsod-aRNA and Pbrbt5-aRNA isolates in the presence of argentilactone indicates the importance of these genes in the response of Paracoccidioides spp. to argentilactone. The response of the P. lutzii cell wall to argentilactone treatment was also evaluated. The results showed that argentilactone caused a decrease in the levels of polymers in the cell wall. These results suggest that argentilactone is a potential candidate for antifungal therapy. PMID:26734764

  19. [Microclimatic properties of the Triatoma brasiliensis habitat].

    PubMed

    Lorenzo, M G; Guarneri, A A; Pires, H H; Diotaiuti, L; Lazzari, C R

    2000-01-01

    Vector-borne transmission of Chagas disease in Northeast Brazil is basically by Triatoma brasiliensis. It is thus crucial to determine this species' microclimatic preferences as limiting factors for its distribution and ability to infest domestic environments. We analyze the microclimatic properties of the shelters in which these insects are found in wild, domestic, and peridomiciliary environments in the State of Ceará, at Brazil. We measure temperature and relative humidity (RH) every 15 minutes for 3 days. Thermal variation was greatly dampened inside both domiciliary refuges and the more protected internal places in wild stony sites. For RH, we observed a similar dampening pattern, but mean RH was lower in both domiciliary refuges and wild ones inside stony sites as compared to reference levels in the surrounding environment. The results are discussed with regard to this species' microclimatic preferences in the laboratory and its potential as determinants of its geographical distribution. PMID:11119321

  20. Susceptibility of species within the Sporothrix schenckii complex to a panel of killer yeasts.

    PubMed

    Stopiglia, Cheila Denise Ottonelli; Heidrich, Daiane; Sorrentino, Julia Medeiros; Vieira, Fabiane Jamono; Landell, Melissa Fontes; Valente, Patrícia; Scroferneker, Maria Lúcia

    2014-06-01

    The Sporothrix schenckii complex is the etiologic agent of sporotrichosis, a subacute or chronic mycosis which can affect humans and animals. Killer yeasts have been used in the medical field for development of novel antimycotics and biotyping of pathogenic fungi. The action of 18 killer yeasts on the growth of 88 characterized S. schenckii, Sporothrix globosa, Sporothrix brasiliensis, and Sporothrix mexicana clinical and environmental isolates was evaluated. Killer studies were performed on Petri dishes containing cheese black starch agar. The yeasts Candida catenulata (QU26, QU31, QU127, LV102); Trichosporon faecale (QU100); Trichosporon japonicum (QU139); Kluyveromyces lactis (QU30, QU99, QU73); Kazachstania unispora (QU49), Trichosporon insectorum (QU89), and Kluyveromyces marxianus (QU103) showed activity against all strains of the S. schenckii complex tested. Observation by optical microscopy of S. brasiliensis 61 within the inhibition haloes around the colonies of the killer yeasts QU100, QU139, and LV102 showed that there was no conidiation, but there was hyphal proliferation. The toxins were fungistatic against S. brasiliensis 61. There was no difference in susceptibility to the toxins among the S. schenckii species complex. Further investigations are necessary to clearly establish the mechanism of action of the toxins. PMID:23686831

  1. Combined Use of Paracoccidioides brasiliensis Recombinant 27-Kilodalton and Purified 87-Kilodalton Antigens in an Enzyme-Linked Immunosorbent Assay for Serodiagnosis of Paracoccidioidomycosis

    PubMed Central

    Díez, Soraya; Gómez, Beatriz L.; McEwen, Juan G.; Restrepo, Angela; Hay, Rod J.; Hamilton, Andrew J.

    2003-01-01

    The diagnosis of paracoccidioidomycosis (PCM) has relied on the identification of the host's humoral response by using a variety of immunological methods, such as complement fixation and immunodiffusion. Although these approaches are useful, historically their sensitivity and specificity have often been compromised by the use of complex mixtures of undefined antigens. The use of combinations of purified, well-characterized antigens appears preferable and may yield optimum results. Accordingly an indirect enzyme-linked immunosorbent assay (ELISA) using combinations of the previously described 27-kDa recombinant antigen and the 87-kDa heat shock protein were used for diagnosis and follow-up of patients with PCM. A total of 37 patients classified according to their clinical presentations (7 with the acute or subacute form of the disease, 22 with the chronic form of the disease, and 8 with the chronic unifocal form) were studied. Eighteen of these patients were also evaluated at every follow-up appointment. Forty serum samples from patients with other diseases and 50 serum samples from healthy individuals were also studied. Detection of anti-27-kDa and anti-87-kDa antibodies in sera of patients with PCM by ELISA using a combination of the two purified proteins showed a sensitivity of 92% with a specificity of 88% in comparison with normal human sera and 90% in comparison with the heterologous sera. These results demonstrated a significant increase in sensitivity and specificity compared to results when the antigens were used separately. Thus, the use of combinations of well-defined antigens appears to offer clear advantages over the use of single antigens when diagnosing PCM. PMID:12682142

  2. Rubber Tree (Hevea brasiliensis Muell. Arg).

    PubMed

    Venkatachalam, Perumal; Jayashree, Radha; Rekha, Karumamkandathil; Sushmakumari, Sreedharannair; Sobha, Sankaren; Kumari Jayasree, Parukkuttyamma; Kala, Radha Gopikkuttanunithan; Thulaseedharan, Arjunan

    2006-01-01

    Rubber tree (Hevea brasiliensis Muell. Arg.) is an important industrial crop for natural rubber production. At present, more than 9.5 million hectares in about 40 countries are devoted to rubber tree cultivation with a production about 6.5 million tons of dry rubber each year. The world supply of natural rubber is barely keeping up with a global demand for 12 million tons of natural rubber in 2020. Tapping panel dryness (TPD) is a complex physiological syndrome widely found in rubber tree plantations, which causes severe yield and crop losses in natural rubber producing countries. Currently, there is no effective prevention or treatment for this serious malady. As it is a perennial tree crop, the integration of specific desired traits through conventional breeding is both time-consuming and labour-intensive. Genetic transformation with conventional breeding is certainly a more promising tool for incorporation of agronomically important genes that could improve existing Hevea genotype. This chapter provides an Agrobacterium-mediated transformation protocol for rubber tree using immature anther-derived calli as initial explants. We have applied this protocol to generate genetically engineered plants from a high yielding Indian clone RRII 105 of Hevea brasiliensis (Hb). Calli were co-cultured with Agrobacterium tumefaciens harboring a plasmid vector containing the Hb superoxide dismutase (SOD) gene and the reporter gene used was beta-glucuronidase (GUS) gene (uidA). The selectable marker gene used was neomycin phosphotransferase (nptII) and kanamycin was used as selection agent. We found that a suitable transformation protocol for Hevea consists of a 3-d co-cultivation with Agrobacterium in the presence of 20 mM acetosyringone, 15 mM betaine HCl, and 11.55 mM proline followed by selection on medium containing 300 mg/L kanamycin. Transformed calli surviving on medium containing 300 mg/L kanamycin showed a strong GUS-positive reaction. Upon subsequent subculture into fresh media, we obtained somatic embryogenesis and germinated plantlets, which were found to be GUS positive. The integration of uidA, nptII, and HbSOD transgenes into Hevea genome was confirmed by polymerase chain reaction (PCR) as well as Southern blot analysis. PMID:17033060

  3. Cryptic Chromosomal Diversity in the Complex "Geophagus" brasiliensis (Perciformes, Cichlidae).

    PubMed

    Oliveira, Isabel Araújo; Argolo, Leandro Araújo; Bitencourt, Jamille de Araújo; Diniz, Débora; Vicari, Marcelo Ricardo; Affonso, Paulo Roberto Antunes de Mello

    2016-02-01

    Among American cichlids, Geophagus stands out as a species-rich genus widespread over neotropical region. Despite their diversity and confusing taxonomy, only few and basic chromosomal reports are available in populations/species along Atlantic coast, hindering our understanding about evolutionary trends in this genus. Therefore, detailed chromosomal studies were performed in "Geophagus" brasiliensis complex from coastal rivers in northeastern Brazil, totalizing seven populations of Geophagus brasiliensis and one of Geophagus itapicuruensis. All samples shared a diploid number (2n) of 48 divided into 2 submetacentric and 46 subtelocentric/acrocentric chromosomes with (peri)centromeric heterochromatin, hypothesized as a symplesiomorphy for Geophagini. Although G. itapicuruensis and two populations of G. brasiliensis presented single NORs on short arms, multiple GC-rich rDNA sites were observed in the remaining G. brasiliensis samples, ranging from three to six NOR-bearing chromosomes. Inversely, 5S rDNA sites were invariably located at interstitial region on a st/a pair, nonsyntenic to NORs. A compilation of the data set in Geophagus shows that their chromosomal evolution has been driven by pericentric inversions and microstructural changes. Besides, the divergence found in northeastern Brazil places this region as a biodiversity hotspot. A taxonomic revision in the complex "Geophagus" brasiliensis is recommended with the support of cytogenetic analyses. PMID:26683087

  4. ANIMAL MODEL OF NIPPOSTRONGYLUS BRASILIENSIS AND HELIGMOSOMOIDES POLYGYRUS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal models of Nippostrongylus brasiliensis and Heligmosomoides polygyrus infection are powerful tools for the investigation of the basic biology of immune responses and protective immunity. In particular they model the induction and maintenance of Th2 type immune responses and exhibiting all the ...

  5. Temporal Dynamics of Reproduction in Hemiramphus brasiliensis (Osteichthyes: Hemiramphidae)

    PubMed Central

    de Oliveira, Mônica Rocha

    2014-01-01

    The reproductive aspects of Hemiramphus brasiliensis were analyzed with a view to verify the temporal dynamics of reproduction. This paper presents data on sex ratio, length at first sexual maturity, macroscopic and histological aspects of gonad development, gonadosomatic index (GSI), reproductive period, and fecundity of H. brasiliensis. The fishes were captured from the coastal waters of Rio Grande do Norte, northeastern Brazil. Females of this species predominated in the sampled population and were larger in size than the males. The length at the first sexual maturation of males was 20.8 cm and that of females was 21.5 cm. The macroscopic characteristics of the gonads indicated four maturation stages. Histological studies of gonads of H. brasiliensis showed six phases of oocyte development and four phases of spermatocyte development. The batch fecundity of this species was 1153 (±258.22) mature oocytes for 50 g body weight of female. The microscopic characteristics of gonad development indicate that H. brasiliensis is a multiple spawner, presenting a prolonged reproductive period during the whole year, with a peak in the month of April, and is considered as an opportunistic strategist. PMID:25512946

  6. Isolation and molecular characterization of 1-aminocyclopropane-1-carboxylic acid synthase genes in Hevea brasiliensis.

    PubMed

    Zhu, Jia-Hong; Xu, Jing; Chang, Wen-Jun; Zhang, Zhi-Li

    2015-01-01

    Ethylene is an important factor that stimulates Hevea brasiliensis to produce natural rubber. 1-Aminocyclopropane-1-carboxylic acid synthase (ACS) is a rate-limiting enzyme in ethylene biosynthesis. However, knowledge of the ACS gene family of H. brasiliensis is limited. In this study, nine ACS-like genes were identified in H. brasiliensis. Sequence and phylogenetic analysis results confirmed that seven isozymes (HbACS1-7) of these nine ACS-like genes were similar to ACS isozymes with ACS activity in other plants. Expression analysis results showed that seven ACS genes were differentially expressed in roots, barks, flowers, and leaves of H. brasiliensis. However, no or low ACS gene expression was detected in the latex of H. brasiliensis. Moreover, seven genes were differentially up-regulated by ethylene treatment. These results provided relevant information to help determine the functions of the ACS gene in H. brasiliensis, particularly the functions in regulating ethylene stimulation of latex production. PMID:25690030

  7. Isolation and Molecular Characterization of 1-Aminocyclopropane-1-carboxylic Acid Synthase Genes in Hevea brasiliensis

    PubMed Central

    Zhu, Jia-Hong; Xu, Jing; Chang, Wen-Jun; Zhang, Zhi-Li

    2015-01-01

    Ethylene is an important factor that stimulates Hevea brasiliensis to produce natural rubber. 1-Aminocyclopropane-1-carboxylic acid synthase (ACS) is a rate-limiting enzyme in ethylene biosynthesis. However, knowledge of the ACS gene family of H. brasiliensis is limited. In this study, nine ACS-like genes were identified in H. brasiliensis. Sequence and phylogenetic analysis results confirmed that seven isozymes (HbACS1–7) of these nine ACS-like genes were similar to ACS isozymes with ACS activity in other plants. Expression analysis results showed that seven ACS genes were differentially expressed in roots, barks, flowers, and leaves of H. brasiliensis. However, no or low ACS gene expression was detected in the latex of H. brasiliensis. Moreover, seven genes were differentially up-regulated by ethylene treatment.These results provided relevant information to help determine the functions of the ACS gene in H. brasiliensis, particularly the functions in regulating ethylene stimulation of latex production. PMID:25690030

  8. Draft genome sequence of the rubber tree Hevea brasiliensis

    PubMed Central

    2013-01-01

    Background Hevea brasiliensis, a member of the Euphorbiaceae family, is the major commercial source of natural rubber (NR). NR is a latex polymer with high elasticity, flexibility, and resilience that has played a critical role in the world economy since 1876. Results Here, we report the draft genome sequence of H. brasiliensis. The assembly spans ~1.1 Gb of the estimated 2.15 Gb haploid genome. Overall, ~78% of the genome was identified as repetitive DNA. Gene prediction shows 68,955 gene models, of which 12.7% are unique to Hevea. Most of the key genes associated with rubber biosynthesis, rubberwood formation, disease resistance, and allergenicity have been identified. Conclusions The knowledge gained from this genome sequence will aid in the future development of high-yielding clones to keep up with the ever increasing need for natural rubber. PMID:23375136

  9. Antitumor Properties of the Leaf Essential Oil of Zornia brasiliensis.

    PubMed

    Costa, Emmanoel V; Menezes, Leociley R A; Rocha, Suellen L A; Baliza, Ingrid R S; Dias, Rosane B; Rocha, Clarissa A Gurgel; Soares, Milena B P; Bezerra, Daniel P

    2015-05-01

    Zornia brasiliensis, popularly known as "urinária", "urinana", and "carrapicho", is a medicinal plant used in Brazilian northeast folk medicine as a diuretic and against venereal diseases. The aim of this study was to investigate the chemical composition and antitumor potential of the leaf essential oil of Z. brasiliensis. The essential oil was obtained by hydrodistillation using a Clevenger-type apparatus and analyzed by GC-MS and GC-FID. Its composition was characterized by the presence of trans-nerolidol, germacrene D, trans-caryophyllene, ?-humulene, and farnesene as major constituents. In vitro cytotoxicity of the essential oil and some of its major constituents (trans-nerolidol, trans-caryophyllene, and ?-humulene) was evaluated for tumor cell lines from different histotypes using the Alamar blue assay. The essential oil, but not the constituents tested, presented promising cytotoxicity. Furthermore, mice inoculated with B16-F10 mouse melanoma were used to confirm its in vivo effectiveness. An in vivo antitumor study showed tumor growth inhibition rates of 1.68-38.61?% (50 and 100?mg/kg, respectively). In conclusion, the leaf essential oil of Z. brasiliensis presents trans-nerolidol, germacrene D, trans-caryophyllene, ?-humulene, and farnesene as major constituents and is able to inhibit cell proliferation in cultures as well as in tumor growth in mice. PMID:25856436

  10. High-level intracellular expression of hydroxynitrile lyase from the tropical rubber tree Hevea brasiliensis in microbial hosts.

    PubMed

    Hasslacher, M; Schall, M; Hayn, M; Bona, R; Rumbold, K; Lückl, J; Griengl, H; Kohlwein, S D; Schwab, H

    1997-10-01

    (S)-Hydroxynitrile lyase (Hnl) from the tropical rubber tree Hevea brasiliensis catalyzes the formation of (S)-cyanohydrins from hydrocyanic acid and aldehydes or ketones. This enzyme accepts aliphatic, aromatic, and heterocyclic carbonyl compounds as substrates and is therefore considered a potent biocatalyst for the industrial production of optically active chemicals. Limitations in enzyme supply from natural resources were overcome by production of the enzyme in the microbial host systems Escherichia coli, Saccharomyces cerevisiae, and Pichia pastoris. Expression of Hnl in the prokaryotic system led to the formation of inclusion bodies whereas in both yeast hosts high levels of soluble protein were obtained. Highest yields were obtained in a high cell density batch fermentation of a P. pastoris transformant that expressed heterologous Hnl to about 50% of the soluble cytosolic protein. At a cell density of 100 g/liter cell dry weight, a volume yield of 22 g/liter of heterologous product was obtained. Attempts to produce the Hnl protein extracellularly with the yeast hosts by applying different leader peptide strategies were not successful. Immunofluorescence microscopy studies indicated that the secretion-directed heterologous Hnl protein accumulated in the plasma membrane forming aggregated clusters of inactive protein. PMID:9325140

  11. Vaginal Yeast Infections (For Parents)

    MedlinePLUS

    ... I Help a Friend Who Cuts? Vaginal Yeast Infections KidsHealth > For Teens > Vaginal Yeast Infections Print A ... effect of taking antibiotics. What Is a Yeast Infection? A yeast infection is a common infection caused ...

  12. Yeast Based Sensors

    NASA Astrophysics Data System (ADS)

    Shimomura-Shimizu, Mifumi; Karube, Isao

    Since the first microbial cell sensor was studied by Karube et al. in 1977, many types of yeast based sensors have been developed as analytical tools. Yeasts are known as facultative anaerobes. Facultative anaerobes can survive in both aerobic and anaerobic conditions. The yeast based sensor consisted of a DO electrode and an immobilized omnivorous yeast. In yeast based sensor development, many kinds of yeast have been employed by applying their characteristics to adapt to the analyte. For example, Trichosporon cutaneum was used to estimate organic pollution in industrial wastewater. Yeast based sensors are suitable for online control of biochemical processes and for environmental monitoring. In this review, principles and applications of yeast based sensors are summarized.

  13. Vaginal Yeast Infection

    MedlinePLUS

    ... Skip Content Marketing Share this: Main Content Area Vaginal Yeast Infection Vaginal yeast infection, or vulvovaginal candidiasis, is a common cause of vaginal irritation. Nearly 75 percent of all adult women ...

  14. Vaginal yeast infection

    MedlinePLUS

    Yeast infection - vagina; Vaginal candidiasis; Monilial vaginitis ... Most women have a vaginal yeast infection at some time. Candida albicans is a common type of fungus. It is often found in small amounts in the vagina , mouth, ...

  15. Δ(24)-Sterol Methyltransferase Plays an Important Role in the Growth and Development of Sporothrix schenckii and Sporothrix brasiliensis.

    PubMed

    Borba-Santos, Luana P; Visbal, Gonzalo; Gagini, Thalita; Rodrigues, Anderson M; de Camargo, Zoilo P; Lopes-Bezerra, Leila M; Ishida, Kelly; de Souza, Wanderley; Rozental, Sonia

    2016-01-01

    Inhibition of Δ(24)-sterol methyltransferase (24-SMT) in Sporothrix schenckii sensu stricto and Sporothrix brasiliensis was investigated in vitro. The effects on fungal growth and sterol composition of the 24-SMT inhibitor 22-hydrazone-imidazolin-2-yl-chol-5-ene-3β-ol (H3) were compared to those of itraconazole. MIC and MFC analysis showed that H3 was more effective than itraconazole against both species in both their filamentous and yeast forms. H3 showed fungistatic activity in a time-kill assay, with inhibitory activity stronger than that of itraconazole. GC analysis of cell sterol composition showed that sterols present in control cells (ergosterol and precursors) were completely replaced by 14α-methylated sterols after H3 exposure. Itraconazole only partially inhibited ergosterol synthesis but completely arrested synthesis of other sterols found in control cells, promoting accumulation of nine 14α-methyl sterols. Based on these results, we propose a schematic model of sterol biosynthesis pathways in S. schenckii and S. brasiliensis. Effects on cell morphology due to 24-SMT inhibition by H3 as analyzed by SEM and TEM included irregular cell shape, reduced cytoplasmic electron-density, and reduced thickness of the microfibrillar cell wall layer. Moreover, 24-SMT inhibition by H3 promoted mitochondrial disturbance, as demonstrated by alterations in MitoTracker(®) Red CMXRos fluorescence intensity evaluated by flow cytometry. When used in conjunction with itraconazole, H3 enhanced the effectiveness of itraconazole against all tested strains, reducing at least half (or more) the MIC values of itraconazole. In addition, cytotoxicity assays revealed that H3 was more selective toward these fungi than was itraconazole. Thus, 24-SMT inhibition by H3 was an effective antifungal strategy against S. schenckii and S. brasiliensis. Inhibition of the methylation reaction catalyzed by 24-SMT has a strong antiproliferative effect via disruption of ergosterol homeostasis, suggesting that this enzyme is a promising target for novel antifungal therapies against sporotrichosis, either as sole treatments or in combination with itraconazole. PMID:27014234

  16. Δ24-Sterol Methyltransferase Plays an Important Role in the Growth and Development of Sporothrix schenckii and Sporothrix brasiliensis

    PubMed Central

    Borba-Santos, Luana P.; Visbal, Gonzalo; Gagini, Thalita; Rodrigues, Anderson M.; de Camargo, Zoilo P.; Lopes-Bezerra, Leila M.; Ishida, Kelly; de Souza, Wanderley; Rozental, Sonia

    2016-01-01

    Inhibition of Δ24-sterol methyltransferase (24-SMT) in Sporothrix schenckii sensu stricto and Sporothrix brasiliensis was investigated in vitro. The effects on fungal growth and sterol composition of the 24-SMT inhibitor 22-hydrazone-imidazolin-2-yl-chol-5-ene-3β-ol (H3) were compared to those of itraconazole. MIC and MFC analysis showed that H3 was more effective than itraconazole against both species in both their filamentous and yeast forms. H3 showed fungistatic activity in a time-kill assay, with inhibitory activity stronger than that of itraconazole. GC analysis of cell sterol composition showed that sterols present in control cells (ergosterol and precursors) were completely replaced by 14α-methylated sterols after H3 exposure. Itraconazole only partially inhibited ergosterol synthesis but completely arrested synthesis of other sterols found in control cells, promoting accumulation of nine 14α-methyl sterols. Based on these results, we propose a schematic model of sterol biosynthesis pathways in S. schenckii and S. brasiliensis. Effects on cell morphology due to 24-SMT inhibition by H3 as analyzed by SEM and TEM included irregular cell shape, reduced cytoplasmic electron-density, and reduced thickness of the microfibrillar cell wall layer. Moreover, 24-SMT inhibition by H3 promoted mitochondrial disturbance, as demonstrated by alterations in MitoTracker® Red CMXRos fluorescence intensity evaluated by flow cytometry. When used in conjunction with itraconazole, H3 enhanced the effectiveness of itraconazole against all tested strains, reducing at least half (or more) the MIC values of itraconazole. In addition, cytotoxicity assays revealed that H3 was more selective toward these fungi than was itraconazole. Thus, 24-SMT inhibition by H3 was an effective antifungal strategy against S. schenckii and S. brasiliensis. Inhibition of the methylation reaction catalyzed by 24-SMT has a strong antiproliferative effect via disruption of ergosterol homeostasis, suggesting that this enzyme is a promising target for novel antifungal therapies against sporotrichosis, either as sole treatments or in combination with itraconazole. PMID:27014234

  17. Revalidation and redescription of Triatoma brasiliensis macromelasoma Galvão, 1956 and an identification key for the Triatoma brasiliensis complex (Hemiptera: Reduviidae: Triatominae)

    PubMed Central

    Costa, Jane; Correia, Nathália Cordeiro; Neiva, Vanessa Lima; Gonçalves, Teresa Cristina Monte; Felix, Márcio

    2013-01-01

    Triatoma brasiliensis macromelasoma is revalidated based on the results of previous multidisciplinary studies on the Triatoma brasiliensis complex, consisting of crossing experiments and morphological, biological, ecological and molecular analyses. These taxonomic tools showed the closest relationship between T. b. macromelasoma and Triatoma brasiliensis brasiliensis. T. b. macromelasoma is redescribed based on specimens collected in the type locality and specimens from a F1 colony. The complex now comprises T. b. brasiliensis, T. b. macromelasoma, Triatoma melanica, Triatoma juazeirensis and Triatoma sherlocki. An identification key for all members of the complex is presented. This detailed comparative study of the morphological features of T. b. macromelasoma and the remaining members of the complex corroborates results from multidisciplinary analyses, suggesting that the subspecific status is applicable. This subspecies can be distinguished by the following combination of features: a pronotum with 1+1 narrow brownish-yellow stripes on the submedian carinae, not attaining its apex, hemelytra with membrane cells darkened on the central portion and legs with an incomplete brownish-yellow ring on the apical half of the femora. Because the T. brasiliensis complex is of distinct epidemiological importance throughout its geographic distribution, a precise identification of its five members is important for monitoring and controlling actions against Chagas disease transmission. PMID:24037202

  18. Comparative Genomic Analysis of Human Fungal Pathogens Causing Paracoccidioidomycosis

    PubMed Central

    Desjardins, Christopher A.; Champion, Mia D.; Holder, Jason W.; Muszewska, Anna; Goldberg, Jonathan; Bailão, Alexandre M.; Brigido, Marcelo Macedo; Ferreira, Márcia Eliana da Silva; Garcia, Ana Maria; Grynberg, Marcin; Gujja, Sharvari; Heiman, David I.; Henn, Matthew R.; Kodira, Chinnappa D.; León-Narváez, Henry; Longo, Larissa V. G.; Ma, Li-Jun; Malavazi, Iran; Matsuo, Alisson L.; Morais, Flavia V.; Pereira, Maristela; Rodríguez-Brito, Sabrina; Sakthikumar, Sharadha; Salem-Izacc, Silvia M.; Sykes, Sean M.; Teixeira, Marcus Melo; Vallejo, Milene C.; Walter, Maria Emília Machado Telles; Yandava, Chandri; Young, Sarah; Zeng, Qiandong; Zucker, Jeremy; Felipe, Maria Sueli; Goldman, Gustavo H.; Haas, Brian J.; McEwen, Juan G.; Nino-Vega, Gustavo; Puccia, Rosana; San-Blas, Gioconda; Soares, Celia Maria de Almeida; Birren, Bruce W.; Cuomo, Christina A.

    2011-01-01

    Paracoccidioides is a fungal pathogen and the cause of paracoccidioidomycosis, a health-threatening human systemic mycosis endemic to Latin America. Infection by Paracoccidioides, a dimorphic fungus in the order Onygenales, is coupled with a thermally regulated transition from a soil-dwelling filamentous form to a yeast-like pathogenic form. To better understand the genetic basis of growth and pathogenicity in Paracoccidioides, we sequenced the genomes of two strains of Paracoccidioides brasiliensis (Pb03 and Pb18) and one strain of Paracoccidioides lutzii (Pb01). These genomes range in size from 29.1 Mb to 32.9 Mb and encode 7,610 to 8,130 genes. To enable genetic studies, we mapped 94% of the P. brasiliensis Pb18 assembly onto five chromosomes. We characterized gene family content across Onygenales and related fungi, and within Paracoccidioides we found expansions of the fungal-specific kinase family FunK1. Additionally, the Onygenales have lost many genes involved in carbohydrate metabolism and fewer genes involved in protein metabolism, resulting in a higher ratio of proteases to carbohydrate active enzymes in the Onygenales than their relatives. To determine if gene content correlated with growth on different substrates, we screened the non-pathogenic onygenale Uncinocarpus reesii, which has orthologs for 91% of Paracoccidioides metabolic genes, for growth on 190 carbon sources. U. reesii showed growth on a limited range of carbohydrates, primarily basic plant sugars and cell wall components; this suggests that Onygenales, including dimorphic fungi, can degrade cellulosic plant material in the soil. In addition, U. reesii grew on gelatin and a wide range of dipeptides and amino acids, indicating a preference for proteinaceous growth substrates over carbohydrates, which may enable these fungi to also degrade animal biomass. These capabilities for degrading plant and animal substrates suggest a duality in lifestyle that could enable pathogenic species of Onygenales to transfer from soil to animal hosts. PMID:22046142

  19. Immunomodulatory effect of diethylcarbamazine in mice infected with Nocardia brasiliensis.

    PubMed

    García-Hernández, M; Castro-Corona, M A; Segoviano-Ramírez, J C; Brattig, N W; Medina-De la Garza, C E

    2014-11-01

    We tested whether diethylcarbamazine (DEC) or ivermectin (IVM), both antiparasitic drugs with reported immunomodulatory properties, were able to affect the immune system to potentiate host defense mechanisms and protect against actinomycetoma in a mouse model. Male BALB/c mice of 10-12 weeks of age were injected with either Nocardia brasiliensis or saline solution. Recorded were the effects of a treatment by DEC (6 mg/kg per os daily for one week) or IVM (200 μg/kg subcutaneously on days 1 and 3) on (i) the development of mycetoma lesion, (ii) the expression of reactive oxygen intermediates (ROI) by phagocytes, (iii) the proliferation index of lymphocytes and (iv) antibody production of IgG and IgM. After an initial lesion in all mice, DEC inhibited a full development and progression of actinomycetoma resulting in a reduced lesion size (p < 0.001). IVM had no inhibitory effect on the development of mycetoma. Furthermore, DEC treatment was associated with a significant enhancement of ROI expression (p < 0.05) by polymorphonuclear neutrophils at day 3 after infection. Lymphocyte proliferation in response to N. brasiliensis antigens and concanavalin A in DEC-treated group was higher than in non-treated group at day 21 and 28 postinfection (p < 0.01). Significant changes in antibody response were not observed. By all parameters tested, DEC was superior to IVM regarding immunostimulatory potency. In conclusion, DEC expressed an in vivo influence on the immune status during the infection by N. brasiliensis leading to retrogression of the mycetoma and increasing cellular immune responses. Our findings may indicate a potential use of DEC as a putative adjuvant in infectious disease or vaccination. PMID:25150175

  20. Nippostrongylus brasiliensis: radioresistant IgE antibody-forming cells in infected rats

    SciTech Connect

    Watanabe, N.; Kobayashi, A.

    1989-02-01

    In Nippostrongylus brasiliensis-infected rats, anti-N. brasiliensis IgE antibody production was observed at 20 weeks postinfection, long after the worms, as a source of antigen, had been expelled. The persistent IgE production was not abrogated after whole body irradiation (800 R) administered at 12 or 20 weeks, suggesting the participation of radioresistant IgE-forming cells. Help of T cells and recruitment of B memory cells in the irradiated rats seems to be ruled out by the findings that the irradiation completely inhibited the initiation of anti-N. brasiliensis IgE production in rats shortly after the infection with N. brasiliensis or after primary and secondary immunization with N. brasiliensis-antigen. Moreover, clearance of anti-N. brasiliensis IgE antibody from circulation did not seem to be crucially affected by the irradiation. The radioresistant cells forming anti-N. brasiliensis IgE were most productive in mesenteric lymph nodes as compared to other lymph nodes. The recognition of antigens fractionated by chromatography on Sephadex G-200 was the same for IgE-forming cells from rats 12 weeks after infection as for those from 3 weeks after infection. Based on these results, one of the mechanisms of persistent elevation of IgE antibody in the host infected with helminth parasites might be explained by the participation of radioresistant IgE-forming cells.

  1. Taxonomic and Functional Microbial Signatures of the Endemic Marine Sponge Arenosclera brasiliensis

    PubMed Central

    Trindade-Silva, Amaro E.; Rua, Cintia; Silva, Genivaldo G. Z.; Dutilh, Bas E.; Moreira, Ana Paula B.; Edwards, Robert A.; Hajdu, Eduardo; Lobo-Hajdu, Gisele; Vasconcelos, Ana Tereza; Berlinck, Roberto G. S.; Thompson, Fabiano L.

    2012-01-01

    The endemic marine sponge Arenosclera brasiliensis (Porifera, Demospongiae, Haplosclerida) is a known source of secondary metabolites such as arenosclerins A-C. In the present study, we established the composition of the A. brasiliensis microbiome and the metabolic pathways associated with this community. We used 454 shotgun pyrosequencing to generate approximately 640,000 high-quality sponge-derived sequences (∼150 Mb). Clustering analysis including sponge, seawater and twenty-three other metagenomes derived from marine animal microbiomes shows that A. brasiliensis contains a specific microbiome. Fourteen bacterial phyla (including Proteobacteria, Cyanobacteria, Actinobacteria, Bacteroidetes, Firmicutes and Cloroflexi) were consistently found in the A. brasiliensis metagenomes. The A. brasiliensis microbiome is enriched for Betaproteobacteria (e.g., Burkholderia) and Gammaproteobacteria (e.g., Pseudomonas and Alteromonas) compared with the surrounding planktonic microbial communities. Functional analysis based on Rapid Annotation using Subsystem Technology (RAST) indicated that the A. brasiliensis microbiome is enriched for sequences associated with membrane transport and one-carbon metabolism. In addition, there was an overrepresentation of sequences associated with aerobic and anaerobic metabolism as well as the synthesis and degradation of secondary metabolites. This study represents the first analysis of sponge-associated microbial communities via shotgun pyrosequencing, a strategy commonly applied in similar analyses in other marine invertebrate hosts, such as corals and algae. We demonstrate that A. brasiliensis has a unique microbiome that is distinct from that of the surrounding planktonic microbes and from other marine organisms, indicating a species-specific microbiome. PMID:22768320

  2. Construction of a Nocardia brasiliensis fluorescent plasmid to study Actinomycetoma pathogenicity.

    PubMed

    Salinas-Carmona, Mario C; Rocha-Pizaña, María R

    2011-01-01

    Nocardia brasiliensis, is a bacteria that lives as saprophyte in soil and causes a disease called actinomycetoma in both human and animals. Nocardia brasiliensis is an intracellular, facultative bacterium that replicates and survives within host macrophages. The mechanisms involved in the evasion of the microbicidal actions of macrophages remain unclear. The filamentous growth of N. brasiliensis is resistant to unicellular preparations, leading to inaccurate quantification of bacterial numbers by means of colony forming units (CFU). As successful survival studies with green fluorescent protein (GFP)-expressing bacterial strains have been reported, we constructed a recombinant GFP-expressing strain of N. brasiliensis. The virulence of the modified strain is maintained because it induces mycetoma in BALB/c mice. This new strain can be used for bacterial survival assays using cytometry and to elucidate the pathogenicity mechanisms in Actinomycetoma infection. PMID:20875450

  3. Isolation and characterization of microsatellite markers in the Serra Spanish mackerel, Scomberomorus brasiliensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thirteen nuclear-encoded microsatellites from a genomic DNA library of Serra Spanish mackerel, Scomberomorus brasiliensis, were isolated and characterized. The microsatellites include 10 perfect repeats (8 tetranucleotide and 2 dinucleotide) and 3 imperfect repeats (2 tetranucleotide and 1 dinucleo...

  4. In vitro activities of the new antitubercular agents PA-824 and BTZ043 against Nocardia brasiliensis.

    PubMed

    Vera-Cabrera, Lucio; Campos-Rivera, Mayra Paola; Gonzalez-Martinez, Norma Alejandra; Ocampo-Candiani, Jorge; Cole, Stewart T

    2012-07-01

    The in vitro activity of PA-824 and BTZ043 against 30 Nocardia brasiliensis isolates was tested. The MIC(50) and MIC(90) values for PA-824 were both >64 μg/ml. The same values for BTZ043 were 0.125 and 0.250 μg/ml. Given the MIC values for benzothiazinone (BTZ) compounds, we consider them good candidates to be tested in vivo against N. brasiliensis. PMID:22526312

  5. Phylogenetic Analysis Reveals a High Prevalence of Sporothrix brasiliensis in Feline Sporotrichosis Outbreaks

    PubMed Central

    Rodrigues, Anderson Messias; de Melo Teixeira, Marcus; de Hoog, G. Sybren; Schubach, Tânia Maria Pacheco; Pereira, Sandro Antonio; Fernandes, Geisa Ferreira; Bezerra, Leila Maria Lopes; Felipe, Maria Sueli; de Camargo, Zoilo Pires

    2013-01-01

    Sporothrix schenckii, previously assumed to be the sole agent of human and animal sporotrichosis, is in fact a species complex. Recently recognized taxa include S. brasiliensis, S. globosa, S. mexicana, and S. luriei, in addition to S. schenckii sensu stricto. Over the last decades, large epidemics of sporotrichosis occurred in Brazil due to zoonotic transmission, and cats were pointed out as key susceptible hosts. In order to understand the eco-epidemiology of feline sporotrichosis and its role in human sporotrichosis a survey was conducted among symptomatic cats. Prevalence and phylogenetic relationships among feline Sporothrix species were investigated by reconstructing their phylogenetic origin using the calmodulin (CAL) and the translation elongation factor-1 alpha (EF1?) loci in strains originated from Rio de Janeiro (RJ, n?=?15), Rio Grande do Sul (RS, n?=?10), Paraná (PR, n?=?4), São Paulo (SP, n?=?3) and Minas Gerais (MG, n?=?1). Our results showed that S. brasiliensis is highly prevalent among cats (96.9%) with sporotrichosis, while S. schenckii was identified only once. The genotype of Sporothrix from cats was found identical to S. brasiliensis from human sources confirming that the disease is transmitted by cats. Sporothrix brasiliensis presented low genetic diversity compared to its sister taxon S. schenckii. No evidence of recombination in S. brasiliensis was found by split decomposition or PHI-test analysis, suggesting that S. brasiliensis is a clonal species. Strains recovered in states SP, MG and PR share the genotype of the RJ outbreak, different from the RS clone. The occurrence of separate genotypes among strains indicated that the Brazilian S. brasiliensis epidemic has at least two distinct sources. We suggest that cats represent a major host and the main source of cat and human S. brasiliensis infections in Brazil. PMID:23818999

  6. [Primary cutaneous Nocardia brasiliensis cellulitis in immunocompetent child].

    PubMed

    Shachor-Meyouhas, Yael; Ravid, Sarit; Suhair, Hanna; Kassis, Imad

    2012-08-01

    Primary cutaneous nocardiosis is an infrequent infection among children, generally affecting immunocompromised hosts. It is caused by Gram positive bacteria, partially alcohol and acid resistant which are saprophytes of the soil, water and organic matter. In most cases the causal agent enters through inhalation, and hematogenous dissemination may occur mainly among the immune compromised patients. Direct cutaneous inoculation is less frequent, especially among children. We report an 8-year old female who lives in an urban house with a small garden, who presented with an ulcer on her right shin accompanied by surrounding cellulitis, pain, swelling and fever. The patient's medical history was unremarkable, with no exposure to animals or travelling, except for rafting on the Jordan River the previous week. Culture from the ulcer grew Nocardia brasiliensis, and she recovered after 8 weeks of therapy with trimethoprim-sulphamethoxazole. PMID:23350294

  7. Drimanes from Drimys brasiliensis with leishmanicidal and antimalarial activity

    PubMed Central

    Claudino, Vanessa Duarte; da Silva, Kesia Caroline; Cechinel, Valdir; Yunes, Rosendo Augusto; Monache, Franco Delle; Giménez, Alberto; Salamanca, Efrain; Gutierrez-Yapu, David; Malheiros, Angela

    2013-01-01

    This paper evaluates CHCl3 and CH3OH extracts of the stem bark, branches and leaves of Drimys brasiliensis and drimane sesquiterpenes isolated from the stem bark against strains of Leishmania amazonensis and Leishmania braziliensis promastigotes and Plasmodium falciparum trophozoites. All of the extracts and compounds were tested in cell lines in comparison with reference standards and cell viability was determined by the XTT method. The CHCl3 and CH3OH extracts from the stem bark and branches yielded promising results against two strains of Leishmania, with 50% inhibitory concentrations (IC50 ) values ranging from 39-100 µg/mL. The CHCl3 extract of the stem bark returned IC50 values of 39 and 40.6 µg/mL for L. amazonensis and L. braziliensis, respectively. The drimanes were relatively effective: 1-?-(p-coumaroyloxy)-polygodial produced IC50 values of 5.55 and 2.52 µM for L. amazonensis and L. braziliensis, respectively, compared with 1-?-(p-methoxycinnamoyl)-polygodial, which produced respective IC50 values of 15.85 and 17.80 µM. The CHCl3 extract demonstrated activity (IC50 of 3.0 µg/mL) against P. falciparum. The IC50 values of 1-?-(p-cumaroyloxyl)-polygodial and 1-?-(p-methoxycinnamoyl)-polygodial were 1.01 and 4.87 µM, respectively, for the trophozoite strain. Therefore, the results suggest that D. brasiliensis is a promising plant from which to obtain new and effective antiparasitic agents. PMID:23579790

  8. Cloning, heterologous expression and characterization of ascorbate peroxidase (APX) gene in laticifer cells of rubber tree (Hevea brasiliensis Muell. Arg.).

    PubMed

    Chao, Jinquan; Zhang, Shixin; Chen, Yueyi; Tian, Wei-Min

    2015-12-01

    Ascorbate peroxidases (APXs) are a kind of crucial enzymes for removing reactive oxygen species (ROS) in plant cell. In the present study, a full-length cDNA encoding an APX, designated HbAPX, was isolated from Hevea brasiliensis by the rapid amplification of cDNA ends (RACE) method. HbAPX was 1174-bp in length and contained a 912-bp open reading frame (ORF) encoding a putative protein of 304 amino acids. The predicted molecular mass of HbAPX was 27.6 kDa (kDa) with an isoelectric point (pI) of 6.73. The phylogenetic analysis showed that HbAPX belonged to the cytosolic subgroup and was more relative to PtAPX and MdAPX2. By using PlantCare online analysis, such cis-acting elements as W-box and MRE were detected in the promoter region of HbAPX. Overproduction of recombinant HbAPX protein either in Escherichia coli or yeast enhanced their tolerance to such abiotic stresses as Cu(2+), Zn(2+), Na(2+) and hydrogen peroxide (H2O2). Ethrel application significantly down-regulated the expression of HbAPX and inhibited the activity of HbAPX in vivo. The ethrel-caused down-regulation of HbAPX may disturb the redox homeostasis in laticifer cells of rubber tree. PMID:26519821

  9. Prions in Yeast

    PubMed Central

    Liebman, Susan W.; Chernoff, Yury O.

    2012-01-01

    The concept of a prion as an infectious self-propagating protein isoform was initially proposed to explain certain mammalian diseases. It is now clear that yeast also has heritable elements transmitted via protein. Indeed, the “protein only” model of prion transmission was first proven using a yeast prion. Typically, known prions are ordered cross-? aggregates (amyloids). Recently, there has been an explosion in the number of recognized prions in yeast. Yeast continues to lead the way in understanding cellular control of prion propagation, prion structure, mechanisms of de novo prion formation, specificity of prion transmission, and the biological roles of prions. This review summarizes what has been learned from yeast prions. PMID:22879407

  10. Antagonistic Activity of Nocardia brasiliensis PTCC 1422 Against Isolated Enterobacteriaceae from Urinary Tract Infections.

    PubMed

    Jalali, Hossnieh Kafshdar; Salamatzadeh, Abdolreza; Jalali, Arezou Kafshdar; Kashani, Hamed Haddad; Asbchin, Salman Ahmadi; Issazadeh, Khosro

    2016-03-01

    The main drawback of current antibiotic therapies is the emergence and rapid increase in antibiotic resistance. Nocardiae are aerobic, Gram-positive, catalase-positive, non-motile actinomycetes. Nocardia brasiliensis was reported as antibiotic producer. The purpose of the study was to determine antibacterial activity of N. brasiliensis PTCC 1422 against isolated Enterobacteriaceae from urinary tract infections (UTIs). The common bacteria from UTIs were isolated from hospital samples. Antimicrobial susceptibility test was performed for the isolated pathogens using Kirby-Bauer disk diffusion method according to clinical and Laboratory Standards Institute guideline. Antagonistic activity of N. brasiliensis PTCC 1422 was examined with well diffusion methods. Supernatant of N. brasiliensis PTCC 1422 by submerged culture was analyzed with gas chromatography-mass spectrometry. Isolated strains included Escherichia coli, Klebsiella pneumoniae, Serratia marcescens and Proteus mirabilis. The most common pathogen isolated was E. coli (72.5 %). Bacterial isolates revealed the presence of high levels of antimicrobial resistances to ceftriaxone and low levels of resistance to cephalexin. Supernatant of N. brasiliensis PTCC 1422 showed antibacterial activity against all of the isolated microorganisms in well diffusion method. The antibiotic resistance among the uropathogens is an evolving process, so a routine surveillance to monitor the etiologic agents of UTI and the resistance pattern should be carried out timely to choose the most effective empirical treatment by the physicians. Our present investigation indicates that the substances present in the N. brasiliensis PTCC 1422 could be used to inhibit the growth of human pathogen. Antibacterial resistance among bacterial uropathogen is an evolving process. Therefore, in the field on the need of re-evaluation of empirical treatment of UTIs, our present. The study has demonstrated that N. brasiliensis PTCC 1422 has a high potential for the treatment of UTIs. PMID:26920557

  11. Secreted proteomes of different developmental stages of the gastrointestinal nematode Nippostrongylus brasiliensis.

    PubMed

    Sotillo, Javier; Sanchez-Flores, Alejandro; Cantacessi, Cinzia; Harcus, Yvonne; Pickering, Darren; Bouchery, Tiffany; Camberis, Mali; Tang, Shiau-Choot; Giacomin, Paul; Mulvenna, Jason; Mitreva, Makedonka; Berriman, Matthew; LeGros, Graham; Maizels, Rick M; Loukas, Alex

    2014-10-01

    Hookworms infect more than 700 million people worldwide and cause more morbidity than most other human parasitic infections. Nippostrongylus brasiliensis (the rat hookworm) has been used as an experimental model for human hookworm because of its similar life cycle and ease of maintenance in laboratory rodents. Adult N. brasiliensis, like the human hookworm, lives in the intestine of the host and releases excretory/secretory products (ESP), which represent the major host-parasite interface. We performed a comparative proteomic analysis of infective larval (L3) and adult worm stages of N. brasiliensis to gain insights into the molecular bases of host-parasite relationships and determine whether N. brasiliensis could indeed serve as an appropriate model for studying human hookworm infections. Proteomic data were matched to a transcriptomic database assembled from 245,874,892 Illumina reads from different developmental stages (eggs, L3, L4, and adult) of N. brasiliensis yielding∼18,426 unigenes with 39,063 possible isoform transcripts. From this analysis, 313 proteins were identified from ESPs by LC-MS/MS-52 in the L3 and 261 in the adult worm. Most of the proteins identified in the study were stage-specific (only 13 proteins were shared by both stages); in particular, two families of proteins-astacin metalloproteases and CAP-domain containing SCP/TAPS-were highly represented in both L3 and adult ESP. These protein families are present in most nematode groups, and where studied, appear to play roles in larval migration and evasion of the host's immune response. Phylogenetic analyses of defined protein families and global gene similarity analyses showed that N. brasiliensis has a greater degree of conservation with human hookworm than other model nematodes examined. These findings validate the use of N. brasiliensis as a suitable parasite for the study of human hookworm infections in a tractable animal model. PMID:24994561

  12. Secreted Proteomes of Different Developmental Stages of the Gastrointestinal Nematode Nippostrongylus brasiliensis*

    PubMed Central

    Sotillo, Javier; Sanchez-Flores, Alejandro; Cantacessi, Cinzia; Harcus, Yvonne; Pickering, Darren; Bouchery, Tiffany; Camberis, Mali; Tang, Shiau-Choot; Giacomin, Paul; Mulvenna, Jason; Mitreva, Makedonka; Berriman, Matthew; LeGros, Graham; Maizels, Rick M.; Loukas, Alex

    2014-01-01

    Hookworms infect more than 700 million people worldwide and cause more morbidity than most other human parasitic infections. Nippostrongylus brasiliensis (the rat hookworm) has been used as an experimental model for human hookworm because of its similar life cycle and ease of maintenance in laboratory rodents. Adult N. brasiliensis, like the human hookworm, lives in the intestine of the host and releases excretory/secretory products (ESP), which represent the major host-parasite interface. We performed a comparative proteomic analysis of infective larval (L3) and adult worm stages of N. brasiliensis to gain insights into the molecular bases of host-parasite relationships and determine whether N. brasiliensis could indeed serve as an appropriate model for studying human hookworm infections. Proteomic data were matched to a transcriptomic database assembled from 245,874,892 Illumina reads from different developmental stages (eggs, L3, L4, and adult) of N. brasiliensis yielding∼18,426 unigenes with 39,063 possible isoform transcripts. From this analysis, 313 proteins were identified from ESPs by LC-MS/MS—52 in the L3 and 261 in the adult worm. Most of the proteins identified in the study were stage-specific (only 13 proteins were shared by both stages); in particular, two families of proteins—astacin metalloproteases and CAP-domain containing SCP/TAPS—were highly represented in both L3 and adult ESP. These protein families are present in most nematode groups, and where studied, appear to play roles in larval migration and evasion of the host's immune response. Phylogenetic analyses of defined protein families and global gene similarity analyses showed that N. brasiliensis has a greater degree of conservation with human hookworm than other model nematodes examined. These findings validate the use of N. brasiliensis as a suitable parasite for the study of human hookworm infections in a tractable animal model. PMID:24994561

  13. Draft Genome Sequence of Pseudozyma brasiliensis sp. nov. Strain GHG001, a High Producer of Endo-1,4-Xylanase Isolated from an Insect Pest of Sugarcane

    PubMed Central

    Oliveira, Juliana Velasco de Castro; dos Santos, Renato Augusto Corrêa; Borges, Thuanny A.

    2013-01-01

    Here, we present the nuclear and mitochondrial genome sequences of Pseudozyma brasiliensis sp. nov. strain GHG001. P. brasiliensis sp. nov. is the closest relative of Pseudozyma vetiver. P. brasiliensis sp. nov. is capable of growing on xylose or xylan as a sole carbon source and has great biotechnological potential. PMID:24356824

  14. Draft Genome Sequence of Pseudozyma brasiliensis sp. nov. Strain GHG001, a High Producer of Endo-1,4-Xylanase Isolated from an Insect Pest of Sugarcane.

    PubMed

    Oliveira, Juliana Velasco de Castro; Dos Santos, Renato Augusto Corrêa; Borges, Thuanny A; Riaño-Pachón, Diego Mauricio; Goldman, Gustavo Henrique

    2013-01-01

    Here, we present the nuclear and mitochondrial genome sequences of Pseudozyma brasiliensis sp. nov. strain GHG001. P. brasiliensis sp. nov. is the closest relative of Pseudozyma vetiver. P. brasiliensis sp. nov. is capable of growing on xylose or xylan as a sole carbon source and has great biotechnological potential. PMID:24356824

  15. Apoptosis in yeast.

    PubMed

    Madeo, Frank; Herker, Eva; Wissing, Silke; Jungwirth, Helmut; Eisenberg, Tobias; Fröhlich, Kai-Uwe

    2004-12-01

    Apoptosis is a highly regulated cellular suicide program crucial for metazoan development. However, dysfunction of apoptosis also leads to several diseases. Yeast undergoes apoptosis after application of acetic acid, sugar- or salt-stress, plant antifungal peptides, or hydrogen peroxide. Oxygen radicals seem to be key elements of apoptotic execution, conserved during evolution. Furthermore, several yeast orthologues of central metazoan apoptotic regulators have been identified, such as a caspase and a caspase-regulating serine protease. In addition, physiological occurrence of cell death has been detected during aging and mating in yeast. The finding of apoptosis in yeast, other fungi and parasites is not only of great medical relevance but will also help to understand some of the still unknown molecular mechanisms at the core of apoptotic execution. PMID:15556039

  16. Anaerobic yeast killer systems.

    PubMed

    Polonelli, L; Menozzi, M G; Campani, L; Gerloni, M; Conti, S; Morace, G; Chezzi, C

    1992-05-01

    The influence of anaerobic conditions on the expression of the killer phenomenon of several yeast isolates belonging to recognized killer systems coded by different genetic determinants (Pichia spp., Kluyveromyces lactis, Saccharomyces cerevisiae) was studied. Anaerobiosis influenced the activity of killer toxins from some individual isolates of the genera Pichia and Saccharomyces on sensitive strains of P. anomala, K. lactis and Candida albicans. However, no influence was detectable on a S. cerevisiae sensitive isolate. Thus, anaerobic conditions seem to interfere more with the metabolic process of sensitive strains than with toxin production by killer yeasts. The selection of a panel of killer yeasts, able to display their activity against reference sensitive yeast isolates under anaerobic conditions in a medium that favored the growth of anaerobes, allowed the use of the killer system to type Bacteroides fragilis isolates for epidemiological purposes. PMID:1397211

  17. Yeast infections (image)

    MedlinePLUS

    Yeast infections may follow a course of antibiotics that were prescribed for another purpose. The antibiotics change the normal "balance" between organisms in the vagina by suppressing the growth of protective bacteria that normally have an antifungal effect.

  18. Pexophagy in yeasts.

    PubMed

    Oku, Masahide; Sakai, Yasuyoshi

    2016-05-01

    Pexophagy, selective degradation of peroxisomes via autophagy, is the main system for reducing organelle abundance. Elucidation of the molecular machinery of pexophagy has been pioneered in studies of the budding yeast Saccharomyces cerevisiae and the methylotrophic yeasts Pichia pastoris and Hansenula polymorpha. Recent analyses using these yeasts have elucidated the molecular machineries of pexophagy, especially in terms of the interactions and modifications of the so-called adaptor proteins required for guiding autophagic membrane biogenesis on the organelle surface. Based on the recent findings, functional relevance of pexophagy and another autophagic pathway, mitophagy (selective autophagy of mitochondria), is discussed. We also discuss the physiological importance of pexophagy in these yeast systems. This article is part of a Special Issue entitled: Peroxisomes edited by Ralf Erdmann. PMID:26409485

  19. Yeast Infection (Candidiasis)

    MedlinePLUS

    ... pain behind the breastbone. Self-Care Guidelines Most yeast infections can be prevented by keeping body-fold areas clean and dry. Diabetics should keep their blood sugar under good control. Treat skin infection with a ...

  20. In vitro susceptibility of antifungal drugs against Sporothrix brasiliensis recovered from cats with sporotrichosis in Brazil.

    PubMed

    Brilhante, Raimunda Sâmia Nogueira; Rodrigues, Anderson Messias; Sidrim, José Júlio Costa; Rocha, Marcos Fábio Gadelha; Pereira, Sandro Antonio; Gremião, Isabella Dib Ferreira; Schubach, Tânia Maria Pacheco; de Camargo, Zoilo Pires

    2016-03-01

    Sporotrichosis is an important subcutaneous mycosis of humans and animals. Classically, the disease is acquired upon traumatic inoculation of Sporothrix propagules from contaminated soil and plant debris. In addition, the direct horizontal transmission of Sporothrix among animals and the resulting zoonotic infection in humans highlight an alternative and efficient rout of transmission through biting and scratching. Sporothrix brasiliensis is the most virulent species of the Sporothrix schenckii complex and is responsible for the long-lasting outbreak of feline sporotrichosis in Brazil. However, antifungal susceptibility data of animal-borne isolates is scarce. Therefore, this study evaluated the in vitro activity of amphotericin B, caspofungin, itraconazole, voriconazole, fluconazole, and ketoconazole against animal-borne isolates of S. brasiliensis. The susceptibility tests were performed through broth microdilution (M38-A2). The results show the relevant activity of itraconazole, amphotericin B, and ketoconazole against S. brasiliensis, with the following MIC ranges: 0.125-2, 0.125-4 and 0.0312-2 μg/ml, respectively. Caspofungin was moderately effective, displaying higher variation in MIC values (0.25-64 μg/ml). Voriconazole (2-64 μg/ml) and fluconazole (62.5-500 μg/ml) showed low activity against S. brasiliensis strains. This study contributed to the characterization of the in vitro antifungal susceptibility of strains of S. brasiliensis recovered from cats with sporotrichosis, which have recently been considered the main source of human infections. PMID:26591009

  1. Study of nucleolar behavior during spermatogenesis in Martarega brasiliensis (Heteroptera, Notonectidae).

    PubMed

    Pereira, L L V; Alevi, K C C; Moreira, F F F; Barbosa, J F; Silistino-Souza, E R; Silva Júnior, F C; Souza-Firmino, T S; Banho, C A; Itoyama, M M

    2015-01-01

    Few cytogenetic studies have been undertaken using aquatic heteropterans and the nucleolar behavior of these insects has been described in only four species, Limnogonus aduncus, Brachymetra albinerva, Halobatopsis platensis, and Cylindrostethus palmaris. The nucleolus is a cellular structure related to biosynthetic activity and it exhibits a peculiar behavior in the heteropterans of the Triatominae subfamily; it persists during all stages of meiosis. Thus, this study aims to analyze spermatogenesis in Martarega brasiliensis, with an emphasis on nucleolar behavior. Twenty M. brasiliensis adult males were used and collected from the Municipal reservoir in the city of São José do Rio Preto, São Paulo, Brazil. The species were fixed in methanol:acetic acid (3:1), then dissected, and the testicles were extracted, torn apart, and impregnated with silver ions. During prophase, the nuclei of M. brasiliensis were composed of the nucleolus and nucleolar corpuscles, which varied in number from one to four, emphasizing that this insect has great synthetic activity during meiosis. The analysis of cells in metaphase I showed that M. brasiliensis presents a nucleolar organizing region in at least one autosome. Furthermore, the phenomenon of nucleolar persistence was not observed. All spermatids presented nucleolar markings that varied in number and position according to the stage of elongation. Moreover, it was also possible to highlight the presence of a vesicle in spermatids. Thus, this paper describes the nucleolar behavior of M. brasiliensis and highlights important characteristics during spermatogenesis, thus, increasing the knowledge about the biology of these aquatic heteropterans. PMID:26345830

  2. Nitrile Metabolizing Yeasts

    NASA Astrophysics Data System (ADS)

    Bhalla, Tek Chand; Sharma, Monica; Sharma, Nitya Nand

    Nitriles and amides are widely distributed in the biotic and abiotic components of our ecosystem. Nitrile form an important group of organic compounds which find their applications in the synthesis of a large number of compounds used as/in pharmaceutical, cosmetics, plastics, dyes, etc>. Nitriles are mainly hydro-lyzed to corresponding amide/acid in organic chemistry. Industrial and agricultural activities have also lead to release of nitriles and amides into the environment and some of them pose threat to human health. Biocatalysis and biotransformations are increasingly replacing chemical routes of synthesis in organic chemistry as a part of ‘green chemistry’. Nitrile metabolizing organisms or enzymes thus has assumed greater significance in all these years to convert nitriles to amides/ acids. The nitrile metabolizing enzymes are widely present in bacteria, fungi and yeasts. Yeasts metabolize nitriles through nitrilase and/or nitrile hydratase and amidase enzymes. Only few yeasts have been reported to possess aldoxime dehydratase. More than sixty nitrile metabolizing yeast strains have been hither to isolated from cyanide treatment bioreactor, fermented foods and soil. Most of the yeasts contain nitrile hydratase-amidase system for metabolizing nitriles. Transformations of nitriles to amides/acids have been carried out with free and immobilized yeast cells. The nitrilases of Torulopsis candida>and Exophiala oligosperma>R1 are enantioselec-tive and regiospecific respectively. Geotrichum>sp. JR1 grows in the presence of 2M acetonitrile and may have potential for application in bioremediation of nitrile contaminated soil/water. The nitrilase of E. oligosperma>R1 being active at low pH (3-6) has shown promise for the hydroxy acids. Immobilized yeast cells hydrolyze some additional nitriles in comparison to free cells. It is expected that more focus in future will be on purification, characterization, cloning, expression and immobilization of nitrile metabolizing enzymes of yeasts.

  3. Modeling brewers' yeast flocculation

    PubMed

    van Hamersveld EH; van der Lans RG; Caulet; Luyben

    1998-02-01

    Flocculation of yeast cells occurs during the fermentation of beer. Partway through the fermentation the cells become flocculent and start to form flocs. If the environmental conditions, such as medium composition and fluid velocities in the tank, are optimal, the flocs will grow in size large enough to settle. After settling of the main part of the yeast the green beer is left, containing only a small amount of yeast necessary for rest conversions during the next process step, the lagering. The physical process of flocculation is a dynamic equilibrium of floc formation and floc breakup resulting in a bimodal size distribution containing single cells and flocs. The floc size distribution and the single cell amount were measured under the different conditions that occur during full scale fermentation. Influences on flocculation such as floc strength, specific power input, and total number of yeast cells in suspension were studied. A flocculation model was developed, and the measured data used for validation. Yeast floc formation can be described with the collision theory assuming a constant collision efficiency. The breakup of flocs appears to occur mainly via two mechanisms, the splitting of flocs and the erosion of yeast cells from the floc surface. The splitting rate determines the average floc size and the erosion rate determines the number of single cells. Regarding the size of the flocs with respect to the scale of turbulence, only the viscous subrange needs to be considered. With the model, the floc size distribution and the number of single cells can be predicted at a certain point during the fermentation. For this, the bond strength between the cells, the fractal dimension of the yeast, the specific power input in the tank and the number of yeast cells that are in suspension in the tank have to be known. Copyright 1998 John Wiley & Sons, Inc. PMID:10099210

  4. Phenotypic variability confirmed by nuclear ribosomal DNA suggests a possible natural hybrid zone of Triatoma brasiliensis species complex.

    PubMed

    Costa, Jane; Bargues, Maria Dolores; Neiva, Vanessa Lima; Lawrence, Gena G; Gumiel, Marcia; Oliveira, Genova; Cabello, Pedro; Lima, Marli Maria; Dotson, Ellen; Provance, David William; Almeida, Carlos Eduardo; Mateo, Lucia; Mas-Coma, Santiago; Dujardin, Jean Pierre

    2016-01-01

    Triatoma brasiliensis macromelasoma occurs in Pernambuco state, Brazil, which is situated between the distribution areas of Triatoma brasiliensis brasiliensis (north) and Triatoma juazeirensis (south). T. b. macromelasoma displays greater variations in its chromatic phenotype than either T. b. brasiliensis or T. juazeirensis, and patterns reminiscent of one or the other. Experimental crosses from each of these members of the T. brasiliensis species complex generated fertile offspring suggesting that viable hybrids could be present in nature, despite their significant genetic distances. Considering the geographical position of occurrence of the T. b. macromelasoma (in Pernambuco) it was proposed to be an area capable of supporting natural hybridization between T. b. brasiliensis and T. juazeirensis. Since phenotypic variability is expected, this study investigated the existence of intermediate chromatic phenotypes for T. b. macromelasoma in various locations in areas between the T. b. brasiliensis and T. juazeirensis occurrences. Thirteen different color patterns were for the first time characterized and nine of those displayed intermediate phenotypes. Molecular analysis performed using ribosomal DNA intergenic region, grouped all within the T. brasiliensis complex. The intermediate chromatic phenotypes, molecular analysis and experimental crosses all support the distinction of a zone of hybridization that gave rise to the T. b. macromelasoma through homoploidal evolution. PMID:26520796

  5. Forces in yeast flocculation

    NASA Astrophysics Data System (ADS)

    El-Kirat-Chatel, Sofiane; Beaussart, Audrey; Vincent, Stéphane P.; Abellán Flos, Marta; Hols, Pascal; Lipke, Peter N.; Dufrêne, Yves F.

    2015-01-01

    In the baker's yeast Saccharomyces cerevisiae, cell-cell adhesion (``flocculation'') is conferred by a family of lectin-like proteins known as the flocculin (Flo) proteins. Knowledge of the adhesive and mechanical properties of flocculins is important for understanding the mechanisms of yeast adhesion, and may help controlling yeast behaviour in biotechnology. We use single-molecule and single-cell atomic force microscopy (AFM) to explore the nanoscale forces engaged in yeast flocculation, focusing on the role of Flo1 as a prototype of flocculins. Using AFM tips labelled with mannose, we detect single flocculins on Flo1-expressing cells, showing they are widely exposed on the cell surface. When subjected to force, individual Flo1 proteins display two distinct force responses, i.e. weak lectin binding forces and strong unfolding forces reflecting the force-induced extension of hydrophobic tandem repeats. We demonstrate that cell-cell adhesion bonds also involve multiple weak lectin interactions together with strong unfolding forces, both associated with Flo1 molecules. Single-molecule and single-cell data correlate with microscale cell adhesion behaviour, suggesting strongly that Flo1 mechanics is critical for yeast flocculation. These results favour a model in which not only weak lectin-sugar interactions are involved in yeast flocculation but also strong hydrophobic interactions resulting from protein unfolding.

  6. Sporothrix brasiliensis outbreaks and the rapid emergence of feline sporotrichosis.

    PubMed

    Sanchotene, Karine Ortiz; Madrid, Isabel Martins; Klafke, Gabriel Baracy; Bergamashi, Mariana; Della Terra, Paula Portella; Rodrigues, Anderson Messias; de Camargo, Zoilo Pires; Xavier, Melissa Orzechowski

    2015-11-01

    Sporotrichosis is the main subcutaneous mycosis in Brazil, and is caused by Sporothrix schenckii and allied species. Sporothrix propagules present on soil and plant debris may be traumatically inoculated into the cutaneous/ subcutaneous tissues of the warm-blooded host. An alternative route involves direct animal-animal and animal-human transmissions through deep scratches and bites of diseased cats. Sporotrichosis is much more common than previously appreciated with several cases emerging over the years especially in South and Southeast Brazil. We conducted an epidemiological surveillance in endemic areas of feline sporotrichosis in the southern region of Rio Grande do Sul state, Brazil. Over the last 5-year period the number of feline sporotrichosis in Rio Grande increased from 0.75 new cases per month in 2010 to 3.33 cases per month in 2014. The wide geographic distribution of diagnosed cases highlights the dynamics of Sporothrix transmission across urban areas with high population density. Molecular identification down to species level by PCR-RFLP of cat-transmitted Sporothrix revealed the emergence of the clonal offshoot S. brasiliensis during feline outbreaks; this scenario is similar to the epidemics taking place in the metropolitan areas of Rio de Janeiro and São Paulo. Controlling and preventing sporotrichosis outbreaks are essential steps to managing the disease among humans and animals. PMID:26404561

  7. Diversity and antimicrobial potential of culturable heterotrophic bacteria associated with the endemic marine sponge Arenosclera brasiliensis

    PubMed Central

    Rua, Cintia P.J.; Trindade-Silva, Amaro E.; Appolinario, Luciana R.; Venas, Tainá M.; Garcia, Gizele D.; Carvalho, Lucas S.; Lima, Alinne; Kruger, Ricardo; Pereira, Renato C.; Berlinck, Roberto G.S.; Valle, Rogério A.B.; Thompson, Cristiane C.

    2014-01-01

    Marine sponges are the oldest Metazoa, very often presenting a complex microbial consortium. Such is the case of the marine sponge Arenosclera brasiliensis, endemic to Rio de Janeiro State, Brazil. In this investigation we characterized the diversity of some of the culturable heterotrophic bacteria living in association with A. brasiliensis and determined their antimicrobial activity. The genera Endozoicomonas (N = 32), Bacillus (N = 26), Shewanella (N = 17), Pseudovibrio (N = 12), and Ruegeria (N = 8) were dominant among the recovered isolates, corresponding to 97% of all isolates. Approximately one third of the isolates living in association with A. brasiliensis produced antibiotics that inhibited the growth of Bacillus subtilis, suggesting that bacteria associated with this sponge play a role in its health. PMID:25024903

  8. Reproductive Biology of Triatoma brasiliensis (Hemiptera, Triatominae) During the Imaginal Molt.

    PubMed

    Alevi, Kaio Cesar Chaboli; Guerra, Ana Letícia; Imperador, Carlos Henrique Lima; da Rosa, João Aristeu; de Azeredo-Oliveira, Maria Tercília Vilela

    2016-03-01

    The triatomines are vectors of the protozoan Trypanosoma cruzi, etiologic agent of Chagas disease. These insects are sexually active after the imaginal molt. Some aspects have been studied in Triatoma brasiliensis during the imaginal molt, such as autogeny in virgin females and the relationship between blood ingestion by fifth instar nymph and the realization of the imaginal molt. Thus, to aid in the understanding of reproductive biology and developmental physiology of these vectors, this article analyzes the spermatogenesis of T. brasiliensis during the imaginal molt. The analysis of the seminiferous tubules from males in the fifth instar during imaginal molt has demonstrated that T. brasiliensis has only a few spermatids and a plentiful quantity of sperm. Thus, we suggest that during imaginal molt the cell division is disrupted aiming to reduce energy costs and the differentiation into sperm is stimulated to ensure the paternity of the adult male. PMID:26787143

  9. Assessment of plant lectin antifungal potential against yeasts of major importance in medical mycology.

    PubMed

    Klafke, Gabriel Baracy; Moreira, Gustavo Marçal Schmitt Garcia; Monte, Leonardo Garcia; Pereira, Juliano Lacava; Brandolt, Tchana Martinez; Xavier, Melissa Orzechowski; Santi-Gadelha, Tatiane; Dellagostin, Odir Antonio; Pinto, Luciano da Silva

    2013-02-01

    The search for new compounds with antifungal activity is accelerating due to rising yeast and fungal resistance to commonly prescribed drugs. Among the molecules being investigated, plant lectins can be highlighted. The present work shows the potential of six plant lectins which were tested in vitro against yeasts of medical importance, Candida albicans, Candida tropicalis, Candida parapsilosis, Cryptococcus gattii, Cryptococcus neoformans, Malassezia pachydermatis, Rhodotorula sp. and Trichosporon sp. Broth microdilution susceptibility testing was performed in accordance with standard protocols to evaluate antifungal activity. Minimum inhibitory concentration (MIC) was determined at 80% yeast growth inhibition, whereas the minimum fungicidal concentration (MFC) was evaluated after making the subcultures of each dilution. Only C. parapsilosis growth was inhibited by the lectins tested. Abelmoschus esculentus lectin showed the highest MIC (0.97 ?g ml(-1)). Lectins from Canavalia brasiliensis, Mucuna pruriens and Clitoria fairchildiana presented the highest MFC at (3.90 ?g ml(-1)). These results encourage further studies with wider yeast strain selections, and open new perspectives for the development of pharmacological molecules. PMID:23161017

  10. Cutaneous Nocardia brasiliensis infection in an immunocompetent host after ovarian cystectomy: A case study.

    PubMed

    Soma, Sarkar; Saha, Puranjay; Sengupta, Manideepa

    2011-01-01

    Nocardia brasiliensis is a rare human pathogen that is usually associated with localised cutaneous infections. We report a case of primary cutaneous Nocardia brasiliensis infection causing delayed wound healing that developed after ovarian cystectomy in an otherwise healthy 32-year-old woman. The patient was initially treated with cotrimoxazole, however due to intolerance intravenous amikacin was given and gradually the wound healed. The diagnosis was confirmed by demonstrating the causative organism in exudates, and cultures. Early diagnosis as well as early institution of chemotherapy is effective in most patients, and antimicrobial susceptibility testing of the isolate should be performed to identify the best treatment options. PMID:23386874

  11. Therapeutic Effect of Agaricus brasiliensis on Phenylhydrazine-Induced Neonatal Jaundice in Rats

    PubMed Central

    Zhang, Lan; Yuan, Bo; Wang, HuiPing; Gao, Ya

    2015-01-01

    The present study was designed to investigate the effect of Agaricus brasiliensis extract (ABE) on phenylhydrazine-induced neonatal jaundice in rats. Administration of ABE dose-dependently reduced the elevated bilirubin level induced by phenylhydrazine. It can be somewhat supported from the results of in vitro bilirubin degradation experiment. ABE treatment also reduced the total antioxidant status (TAOS), cascade O2?/SOD, level of NF-?B protein, and adrenomedullin (AM). Overall, the results of this study demonstrated that Agaricus brasiliensis extract may be beneficial to reducing bilirubin level without causing hepatotoxicity in neonatal jaundice. PMID:25883968

  12. Immunomodulating Activity of Agaricus brasiliensis KA21 in Mice and in Human Volunteers

    PubMed Central

    Fukuwatari, Yasushi; Okumura, Ko; Takeda, Kazuyoshi; Ishibashi, Ken-ichi; Furukawa, Mai; Ohno, Naohito; Mori, Kazu; Gao, Ming; Motoi, Masuro

    2008-01-01

    We performed studies on murine models and human volunteers to examine the immunoenhancing effects of the naturally outdoor-cultivated fruit body of Agaricus brasiliensis KA21 (i.e. Agaricus blazei). Antitumor, leukocyte-enhancing, hepatopathy-alleviating and endotoxin shock-alleviating effects were found in mice. In the human study, percentage body fat, percentage visceral fat, blood cholesterol level and blood glucose level were decreased, and natural killer cell activity was increased. Taken together, the results strongly suggest that the A. brasiliensis fruit body is useful as a health-promoting food. PMID:18604247

  13. Mapping Yeast Transcriptional Networks

    PubMed Central

    Hughes, Timothy R.; de Boer, Carl G.

    2013-01-01

    The term “transcriptional network” refers to the mechanism(s) that underlies coordinated expression of genes, typically involving transcription factors (TFs) binding to the promoters of multiple genes, and individual genes controlled by multiple TFs. A multitude of studies in the last two decades have aimed to map and characterize transcriptional networks in the yeast Saccharomyces cerevisiae. We review the methodologies and accomplishments of these studies, as well as challenges we now face. For most yeast TFs, data have been collected on their sequence preferences, in vivo promoter occupancy, and gene expression profiles in deletion mutants. These systematic studies have led to the identification of new regulators of numerous cellular functions and shed light on the overall organization of yeast gene regulation. However, many yeast TFs appear to be inactive under standard laboratory growth conditions, and many of the available data were collected using techniques that have since been improved. Perhaps as a consequence, comprehensive and accurate mapping among TF sequence preferences, promoter binding, and gene expression remains an open challenge. We propose that the time is ripe for renewed systematic efforts toward a complete mapping of yeast transcriptional regulatory mechanisms. PMID:24018767

  14. Oxygen requirements of yeasts.

    PubMed Central

    Visser, W; Scheffers, W A; Batenburg-van der Vegte, W H; van Dijken, J P

    1990-01-01

    Type species of 75 yeast genera were examined for their ability to grow anaerobically in complex and mineral media. To define anaerobic conditions, we added a redox indicator, resazurin, to the media to determine low redox potentials. All strains tested were capable of fermenting glucose to ethanol in oxygen-limited shake-flask cultures, even those of species generally regarded as nonfermentative. However, only 23% of the yeast species tested grew under anaerobic conditions. A comparative study with a number of selected strains revealed that Saccharomyces cerevisiae stands out as a yeast capable of rapid growth at low redox potentials. Other yeasts, such as Torulaspora delbrueckii and Candida tropicalis, grew poorly mu max, 0.03 and 0.05 h-1, respectively) under anaerobic conditions in mineral medium supplemented with Tween 80 and ergosterol. The latter organisms grew rapidly under oxygen limitation and then displayed a high rate of alcoholic fermentation. It can be concluded that these yeasts have hitherto-unidentified oxygen requirements for growth. Images PMID:2082825

  15. Alkaloids as Inhibitors of Malate Synthase from Paracoccidioides spp.: Receptor-Ligand Interaction-Based Virtual Screening and Molecular Docking Studies, Antifungal Activity, and the Adhesion Process

    PubMed Central

    Costa, Fausto Guimaraes; Neto, Benedito Rodrigues da Silva; Gonçalves, Ricardo Lemes; da Silva, Roosevelt Alves; de Oliveira, Cecília Maria Alves; Kato, Lucília; Freitas, Carla dos Santos; Giannini, Maria José Soares Mendes; da Silva, Julhiany de Fátima; Soares, Célia Maria de Almeida

    2015-01-01

    Paracoccidioides is the agent of paracoccidioidomycosis. Malate synthase plays a crucial role in the pathogenicity and virulence of various fungi, such as those that are human pathogens. Thus, an inhibitor of this enzyme may be used as a powerful antifungal without side effects in patients once these enzymes are absent in humans. Here, we searched for compounds with inhibitory capacity against the malate synthase of Paracoccidioides species (PbMLS). The three-dimensional (3D) structure of PbMLS was determined using the I-TASSER server. Compounds were selected from the ZINC database. Based on the mechanism underlying the interaction of the compounds with PbMLS, it was possible to identify ?-carboline moiety as a standard key structure. The compounds with ?-carboline moiety that are available in our laboratories were investigated. A total of nine alkaloid compounds were selected. The primary mechanisms of interaction of the alkaloid compounds in the binding pocket of PbMLS were identified and compared with the mechanism of interaction of acetyl coenzyme A (acetyl-CoA). We discovered that the amphipathic nature of the compounds, concomitant with the presence of ?-carboline moiety, was crucial for their stability in the binding pocket of PbMLS. In addition, the importance of a critical balance of the polar and nonpolar contacts of the compounds in this region was observed. Four ?-carboline alkaloid compounds showed the ability to inhibit recombinant PbMLS (PbMLSr) activity, Paracoccidioides species growth, and adhesion of the fungus and PbMLSr to the extracellular matrix components. The cytotoxicity of the alkaloids was also evaluated. PMID:26124176

  16. Yeast killer systems.

    PubMed Central

    Magliani, W; Conti, S; Gerloni, M; Bertolotti, D; Polonelli, L

    1997-01-01

    The killer phenomenon in yeasts has been revealed to be a multicentric model for molecular biologists, virologists, phytopathologists, epidemiologists, industrial and medical microbiologists, mycologists, and pharmacologists. The surprisingly widespread occurrence of the killer phenomenon among taxonomically unrelated microorganisms, including prokaryotic and eukaryotic pathogens, has engendered a new interest in its biological significance as well as its theoretical and practical applications. The search for therapeutic opportunities by using yeast killer systems has conceptually opened new avenues for the prevention and control of life-threatening fungal diseases through the idiotypic network that is apparently exploited by the immune system in the course of natural infections. In this review, the biology, ecology, epidemiology, therapeutics, serology, and idiotypy of yeast killer systems are discussed. PMID:9227858

  17. Strong nucleosomes of yeasts.

    PubMed

    Trifonov, Edward N; Tripathi, Vijay

    2016-02-01

    Yeast genome lacks visibly periodic sequences characteristic of strong nucleosomes (SNs) originally discovered in A. thaliana, C. elegans, and H. sapiens. Yet, the sequences with good match to the (RRRRRYYYYY)n consensus of the SNs do show preference to centromere regions of Schizosaccharomyces pombe, Saccharomyces cerevisiae, and Cryptococcus neoformans - property characteristic of SNs of higher eukaryotes. Candida albicans is the first exception detected so far, where their SNs do not have any affinity to the centromeres, nor pericentromeric regions. Three of the four yeast genomes analyzed possess unique repeating centromere-specific SN sequences (C. albicans, again, is an exception). The results firmly indicate that centromeres of plants, animals, and yeasts in general have special chromatin structure, favoring SNs. PMID:25893982

  18. Evolutionary history of Ascomyceteous Yeasts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yeasts are important for many industrial and biotechnological processes and show remarkable diversity despite morphological similarities. We have sequenced the genomes of 20 ascomyceteous yeasts of taxonomic and industrial importance including members of Saccharomycotina and Taphrinomycotina. A comp...

  19. Genetics of Yeasts

    NASA Astrophysics Data System (ADS)

    Querol, Amparo; Fernández-Espinar, M. Teresa; Belloch, Carmela

    The use of yeasts in biotechnology processes dates back to ancient days. Before 7000 BC, beer was produced in Sumeria. Wine was made in Assyria in 3500 BC, and ancient Rome had over 250 bakeries, which were making leavened bread by 100 BC. And milk has been made into Kefyr and Koumiss in Asia for many centuries (Demain, Phaff, & Kurtzman, 1999). However, the importance of yeast in the food and beverage industries was only realized about 1860, when their role in food manufacturing became evident.

  20. L-arabinose fermenting yeast

    SciTech Connect

    Zhang, Min; Singh, Arjun; Knoshaug, Eric; Franden, Mary Ann; Jarvis, Eric; Suominen, Pirkko

    2010-12-07

    An L-arabinose utilizing yeast strain is provided for the production of ethanol by introducing and expressing bacterial araA, araB and araD genes. L-arabinose transporters are also introduced into the yeast to enhance the uptake of arabinose. The yeast carries additional genomic mutations enabling it to consume L-arabinose, even as the only carbon source, and to produce ethanol. Methods of producing ethanol include utilizing these modified yeast strains. ##STR00001##

  1. Low-cost and low maintenance preservation of Agaricus brasiliensis cultures.

    PubMed

    Maia, Scheila C; Toledo, Rômulo C C; Almeida, Ana Paula M M; da Silva, Romildo; Rinker, Danny Lee; Dias, Eustáquio S

    2012-06-01

    Agaricus brasiliensis cultures quickly lose viability when stored at cool temperatures, even for a short period of time. We evaluated several low-cost preservation methods using varied substrates, preservation solutions, and storage temperatures. Agaricus brasiliensis was intolerant to freezing temperatures, making liquid nitrogen use and deep-freezing methods impossible for its preservation. The best preservation conditions for the A. brasiliensis CS1 strain tested in this study were obtained by using rice as substrate and water as preservation solution, with storage at room temperature or when using soil, mushroom cultivation compost, or rice and stored at 10 °C without preservation solution. Those cultures that were reactivated showed the same productivity attributes as the control. In addition, no effect on productivity or biological efficiency was observed through successive subculturing of the strain (CS1). Parboiled rice was successfully used for other A. brasiliensis strains (CS2, CS5, CS7, CS9, and CS10), and also for Pleurotus ostreatus, P. sajor-caju, and Lentinula edodes. PMID:22806115

  2. Neofusicoccum ribis Associated with Leaf Blight on Rubber (Hevea brasiliensis) in Peninsular Malaysia.

    PubMed

    Nyaka Ngobisa, A I C; Zainal Abidin, M A; Wong, M Y; Wan Noordin, M W D

    2013-03-01

    Hevea brasiliensis is a natural source of rubber and an important plantation tree species in Malaysia. Leaf blight disease caused by Fusicoccum substantially reduces the growth and performance of H. brasiliensis. The aim of this study was to use a combination of both morphological characteristics and molecular data to clarify the taxonomic position of the fungus associated with leaf blight disease. Fusicoccum species were isolated from infected leaves collected from plantations at 3 widely separated locations - Selangor, Perak, and Johor states - in Peninsular Malaysia in 2010. All the isolates were identified according to their conidial patterns and DNA sequences generated from internal transcribed spacers (ITS1 and ITS2), the 5.8S rRNA, and an unknown locus (BotF15) containing microsatellite repeats. Based on taxonomic and sequence data, Neofusicoccum ribis was identified as the main cause of leaf blight disease in H. brasiliensis in commercial plantations in Malaysia. A pathogenicity trial on detached leaves further confirmed that N. ribis causes leaf blight disease. N. ribis is an important leaf pathogen, and its detection in Malaysia has important implications for future planting of H. brasiliensis. PMID:25288924

  3. Initial development of the endocarp in Lithraea brasiliensis Marchand (Anacardiaceae): with taxonomic notes.

    PubMed

    De Oliveira, João M S; Mariath, Jorge E A

    2015-09-01

    Investigation into the initial developmental stages of a given structure is fundamental for precise characterization as well as for comparative analysis in relation to other taxa when homologies are established. For the Anacardiaceae family, investigations of the initial development of the pericarp or its basic histological sites, the epicarp, mesocarp and endocarp, are relevant since these regions are of taxonomic and phylogenetic importance. The initial stages of endocarp development in Lithraea brasiliensis were studied using light microscopy. In L. brasiliensis, the fruits are of the drupe type. The endocarp originates exclusively in the epidermis of the locular cavity and is composed of only three strata. The crystalliferous layer, typical in fruits of the Anacardiaceae family, originates in the carpelar mesophyll and runs adjacent to the outermost layer of the endocarp. The endocarp in Lithraea brasiliensis is of the Anacardium type. The results of the present study are important for the identification of the Lithraea species that occur in the state of Rio Grande do Sul. In L. molleoides, the crystalliferous layer was shown to originate from the locular epidermis and this developmental aspect enables it to be differentiated from L. brasiliensis and demonstrates that there is variability of endocarp development in Lithraea. PMID:26221992

  4. Nocardia brasiliensis primary pulmonary nocardiosis with subcutaneous involvement in an immunocompetent patient.

    PubMed

    Amatya, R; Koirala, R; Khanal, B; Dhakal, S S

    2011-01-01

    This is a report of an unusual case of Nocardia brasiliensis causing primary pulmonary nocardiosis with disseminated subcutaneous lesions in an immunocompetent patient. This case highlights the importance of considering nocardiosis as a differential diagnosis in patients with pulmonary and cutaneous lesions and the need for vigorous management for complete cure. PMID:21304201

  5. A life-threatening case of disseminated nocardiosis due to Nocardia brasiliensis.

    PubMed

    Paramythiotou, Elisabeth; Papadomichelakis, Evangelos; Vrioni, Georgia; Pappas, Georgios; Pantelaki, Maria; Kontos, Fanourios; Zerva, Loukia; Armaganidis, Apostolos

    2012-10-01

    Nocardiosis is a rare disease caused by infection with Nocardia species, aerobic actinomycetes with a worldwide distribution. A rare life-threatening disseminated Nocardia brasiliensis infection is described in an elderly, immunocompromised patient. Microorganism was recovered from bronchial secretions and dermal lesions, and was identified using molecular assays. Prompt, timely diagnosis and appropriate treatment ensured a favorable outcome. PMID:23559737

  6. Safety assessment of the royal sun mushroom, Agaricus brasiliensis (higher Basidiomycetes) intake during rat pregnancy.

    PubMed

    Gerenutti, Marli; Tribuiani, Natalia; Oliveira, Bruna Ryzik; Rosa-Castro, Raquel Mendonca; Frizo, Italo; Oshima-Franco, Yoko; Grotto, Denise

    2014-01-01

    In this study, we investigated the reproductive capacity of pregnant rats exposed to daily orally administered powder-dehydrated reconstituted of Agaricus brasiliensis (=Agaricus blazei sensu Murrill), the fetal organogenesis, and the development of the pups. Pregnant rats were exposed for the entire gestational period to water (control) and A. brasiliensis at 300 or 600 mg/kg/day. Fertility and body weight of dams were monitored. Pups were monitored for body weight, offspring vitality, morphology, and physical and neurobehavioral development. An increase in sternebrae agenesis was observed at the 600 mg/kg/day dose of A. brasiliensis, while incomplete ossification of sternebrae was seen even at a 300 mg/kg/day dose. In conclusion, this study is the first to demonstrate the impact of maternal exposure to A. brasiliensis on the fetal organogenesis and development of offspring in a rat model. The 600 mg/kg/day dose showed some negative effects, and low toxicity was observed at the 300 mg/kg/day dose. PMID:25404217

  7. National Plant Diagnostic Network, Taxonomic training videos: Aphids under the microscope - Cerataphis brasiliensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides provides training to identify the palm aphid, Cerataphis brasiliensis, using a compound microscope and an electronic identification key called “LUCID.” The video demonstrates key morphological structures...

  8. Pulmonary cavitation and skin lesions mimicking tuberculosis in a HIV negative patient caused by Sporothrix brasiliensis

    PubMed Central

    Orofino-Costa, Rosane; Unterstell, Natasha; Carlos Gripp, Alexandre; de Macedo, Priscila Marques; Brota, Arles; Dias, Emylli; de Melo Teixeira, Marcus; Felipe, Maria Sueli; Bernardes-Engemann, Andréa R; Lopes-Bezerra, Leila Maria

    2013-01-01

    A 32-year-old HIV negative male presented with multiple pulmonary cavitation and skin abscesses up to 15 cm in diameter mimicking tuberculosis. Sporothrix brasiliensis was isolated and patient responded well to amphotericin B followed by itraconazole, except the skin lesions that had to be surgical drained to obtain cure. PMID:24432220

  9. A Novel Anelloviridae Species Detected in Tadarida brasiliensis Bats: First Sequence of a Chiropteran Anellovirus

    PubMed Central

    Cibulski, Samuel Paulo; Teixeira, Thais Fumaco; de Sales Lima, Francisco Esmaile; do Santos, Helton Fernandes; Franco, Ana Claudia

    2014-01-01

    Using metagenomic approaches, we identified a novel Torque teno virus from Brazilian free-tailed bats (Tadarida brasiliensis) (TT-TbV). The TT-TbV genome and deduced protein sequences share extremely low identity with known anelloviruses. Due to a high degree of phylogenetic divergence, such putative virus could not be allocated into any Anelloviridae genera. PMID:25359906

  10. IL-13 receptor alpha-2 regulates the immune and functional response to Nippostrongylus brasiliensis infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    IL-13 has a prominent role in host defense against the gastrointestinal nematode, Nippostrongylus brasiliensis; however, the role of IL-13 alpha2 in the immune and functional response to enteric infection is not known. In the current study, we investigated changes in smooth muscle and epithelial ce...

  11. Thermal preferences and limits of Triatoma brasiliensis in its natural environment - Field observations while host searching

    PubMed Central

    Catalá, Silvia; Bezerra, Claudia Mendonça; Diotaiuti, Lileia

    2015-01-01

    The goal of this work was to explore the thermal relationship between foraging Triatoma brasiliensis and its natural habitat during the hottest season in the state of Ceará, Brazil. The thermal profiles were determined using infrared analysis. Although the daily temperature of rock surfaces varied in a wide range, T. brasiliensis selected to walk through areas with temperatures between 31.7-40.5ºC. The temperature of T. brasiliensis body surface ranged from 32.8-34.4ºC, being higher in legs than the abdomen. A strong relationship was found between the temperature of the insect and the temperature of rock crevices where they were hidden (r: 0.96, p < 0.05). The species was active at full sunlight being a clear example of how the light-dark rhythm may be altered, even under predation risk. Our results strongly suggest a thermal borderline for T. brasiliensis foraging activity near 40ºC. The simultaneous determination of insect body and rock temperatures here presented are the only obtained in natural habitats for this or other triatomines. PMID:26517659

  12. Neofusicoccum ribis Associated with Leaf Blight on Rubber (Hevea brasiliensis) in Peninsular Malaysia

    PubMed Central

    Nyaka Ngobisa, A. I. C.; Zainal Abidin, M. A.; Wong, M. Y.; Wan Noordin, M. W. D.

    2013-01-01

    Hevea brasiliensis is a natural source of rubber and an important plantation tree species in Malaysia. Leaf blight disease caused by Fusicoccum substantially reduces the growth and performance of H. brasiliensis. The aim of this study was to use a combination of both morphological characteristics and molecular data to clarify the taxonomic position of the fungus associated with leaf blight disease. Fusicoccum species were isolated from infected leaves collected from plantations at 3 widely separated locations – Selangor, Perak, and Johor states – in Peninsular Malaysia in 2010. All the isolates were identified according to their conidial patterns and DNA sequences generated from internal transcribed spacers (ITS1 and ITS2), the 5.8S rRNA, and an unknown locus (BotF15) containing microsatellite repeats. Based on taxonomic and sequence data, Neofusicoccum ribis was identified as the main cause of leaf blight disease in H. brasiliensis in commercial plantations in Malaysia. A pathogenicity trial on detached leaves further confirmed that N. ribis causes leaf blight disease. N. ribis is an important leaf pathogen, and its detection in Malaysia has important implications for future planting of H. brasiliensis. PMID:25288924

  13. Opportunistic Pathogenic Yeasts

    NASA Astrophysics Data System (ADS)

    Banerjee, Uma

    Advances in medical research, made during the last few decades, have improved the prophylactic, diagnostic and therapeutic capabilities for variety of infections/diseases. However, many of the prophylactic and therapeutic procedures have been seen in many instances to exact a price of host-vulnerability to an expanding group of opportunistic pathogens and yeasts are one of the important members in it. Fortunately amongst the vast majority of yeasts present in nature only few are considered to have the capability to cause infections when certain opportunities predisposes and these are termed as ‘opportunistic pathogenic yeasts.’ However, the term ‘pathogenic’ is quite tricky, as it depends of various factors of the host, the ‘bug’ and the environment to manifest the clinical infection. The borderline is expanding. In the present century with unprecedented increase in number of immune-compromised host in various disciplines of health care settings, where any yeast, which has the capability to grow at 37 ° C (normal body temperature of human), can be pathogenic and cause infection in particular situation

  14. L-arabinose fermenting yeast

    DOEpatents

    Zhang, Min; Singh, Arjun; Suominen, Pirkko; Knoshaug, Eric; Franden, Mary Ann; Jarvis, Eric

    2013-02-12

    An L-arabinose utilizing yeast strain is provided for the production of ethanol by introducing and expressing bacterial araA, araB and araD genes. L-arabinose transporters are also introduced into the yeast to enhance the uptake of arabinose. The yeast carries additional genomic mutations enabling it to consume L-arabinose, even as the only carbon source, and to produce ethanol. A yeast strain engineered to metabolize arabinose through a novel pathway is also disclosed. Methods of producing ethanol include utilizing these modified yeast strains.

  15. L-arabinose fermenting yeast

    DOEpatents

    Zhang, Min; Singh, Arjun; Suominen, Pirkko; Knoshaug, Eric; Franden, Mary Ann; Jarvis, Eric

    2014-09-23

    An L-arabinose utilizing yeast strain is provided for the production of ethanol by introducing and expressing bacterial araA, araB and araD genes. L-arabinose transporters are also introduced into the yeast to enhance the uptake of arabinose. The yeast carries additional genomic mutations enabling it to consume L-arabinose, even as the only carbon source, and to produce ethanol. A yeast strain engineered to metabolize arabinose through a novel pathway is also disclosed. Methods of producing ethanol include utilizing these modified yeast strains.

  16. Development and characterization of microsatellite markers for the medicinal plant Smilax brasiliensis (Smilacaceae) and related species1

    PubMed Central

    Martins, Aline R.; Abreu, Aluana G.; Bajay, Miklos M.; Villela, Priscilla M. S.; Batista, Carlos E. A.; Monteiro, Mariza; Alves-Pereira, Alessandro; Figueira, Glyn M.; Pinheiro, José B.; Appezzato-da-Glória, Beatriz; Zucchi, Maria I.

    2013-01-01

    • Premise of the study: A new set of microsatellite or simple sequence repeat (SSR) markers were developed for Smilax brasiliensis, which is popularly known as sarsaparilla and used in folk medicine as a tonic, antirheumatic, and antisyphilitic. Smilax brasiliensis is sold in Brazilian pharmacies, and its origin and effectiveness are not subject to quality control. • Methods and Results: Using a protocol for genomic library enrichment, primer pairs were developed for 26 microsatellite loci and validated in 17 accessions of S. brasiliensis. Thirteen loci were polymorphic and four were monomorphic. The primers successfully amplified alleles in the congeners S. campestris, S. cissoides, S. fluminensis, S. goyazana, S. polyantha, S. quinquenervia, S. rufescens, S. subsessiliflora, and S. syphilitica. • Conclusions: The new SSR markers described herein are informative tools for genetic diversity and gene flow studies in S. brasiliensis and several congeners. PMID:25202555

  17. Changes in kinematics and aerodynamics over a range of speeds in Tadarida brasiliensis, the Brazilian free-tailed bat

    PubMed Central

    Hubel, Tatjana Y.; Hristov, Nickolay I.; Swartz, Sharon M.; Breuer, Kenneth S.

    2012-01-01

    To date, wake measurements using particle image velocimetry (PIV) of bats in flight have studied only three bat species, all fruit and nectar feeders. In this study, we present the first wake structure analysis for an insectivorous bat. Tadarida brasiliensis, the Brazilian free-tailed bat, is an aerial hunter that annually migrates long distances and also differs strikingly from the previously investigated species morphologically. We compare the aerodynamics of T. brasiliensis with those of other, frugivorous bats and with common swifts, Apus apus, a bird with wing morphology, kinematics and flight ecology similar to that of these bats. The comparison reveals that, for the range of speeds evaluated, the cyclical pattern of aerodynamic forces associated with a wingbeat shows more similarities between T. brasiliensis and A. apus than between T. brasiliensis and other frugivorous bats. PMID:22258554

  18. Extracellular Polysaccharides Produced by Yeasts and Yeast-Like Fungi

    NASA Astrophysics Data System (ADS)

    van Bogaert, Inge N. A.; de Maeseneire, Sofie L.; Vandamme, Erick J.

    Several yeasts and yeast-like fungi are known to produce extracellular polysaccharides. Most of these contain D-mannose, either alone or in combination with other sugars or phosphate. A large chemical and structural variability is found between yeast species and even among different strains. The types of polymers that are synthesized can be chemically characterized as mannans, glucans, phosphoman-nans, galactomannans, glucomannans and glucuronoxylomannans. Despite these differences, almost all of the yeast exopolysaccharides display some sort of biological activity. Some of them have already applications in chemistry, pharmacy, cosmetics or as probiotic. Furthermore, some yeast exopolysaccharides, such as pullulan, exhibit specific physico-chemical and rheological properties, making them useful in a wide range of technical applications. A survey is given here of the production, the characteristics and the application potential of currently well studied yeast extracellular polysaccharides.

  19. Water Transport in Yeasts.

    PubMed

    Sabir, Farzana; Prista, Catarina; Madeira, Ana; Moura, Teresa; Loureiro-Dias, Maria C; Soveral, Graça

    2016-01-01

    Water moves across membranes through the lipid bilayer and through aquaporins, in this case in a regulated manner. Aquaporins belong to the MIP superfamily and two subfamilies are represented in yeasts: orthodox aquaporins considered to be specific water channels and aquaglyceroporins (heterodox aquaporins). In Saccharomyces cerevisiae genome, four aquaporin isoforms were identified, two of which are genetically close to orthodox aquaporins (ScAqy1 and ScAqy2) and the other two are more closely related to the aquaglyceroporins (ScFps1 and ScAqy3). Advances in the establishment of water channels structure are reviewed in this chapter in relation with the mechanisms of selectivity, conductance and gating. Aquaporins are important for key aspects of yeast physiology. They have been shown to be involved in sporulation, rapid freeze-thaw tolerance, osmo-sensitivity, and modulation of cell surface properties and colony morphology, although the underlying exact mechanisms are still unknown. PMID:26721272

  20. Interspecific interactions involving Neoseiulus californicus (Acari: Phytoseiidae) and Agistemus brasiliensis (Acari: Stigmaeidae) as predators of Brevipalpus phoenicis (Acari: Tenuipalpidae).

    PubMed

    da Silva, Marcos Zatti; Sato, Mário Eidi; de Oliveira, Carlos Amadeu Leite; Nicastro, Roberto Lomba

    2015-03-01

    Brevipalpus phoenicis (Geijskes) is associated with the transmission of Citrus leprosis which is considered the main viral disease for the Brazilian citrus production. Mites of the families Stigmaeidae and Phytoseiidae coexist in various agricultural crops, often promoting the biological control of pest mites. The aim of this work was to study the interactions of Neoseiulus californicus (McGregor) (Phytoseiidae) and Agistemus brasiliensis Matioli, Ueckermann & Oliveira (Stigmaeidae), in the presence or absence of B. phoenicis. Two experiments were carried out. In the first, a N. californicus female was placed in each leaf disc arena, with eggs of B. phoenicis and A. brasiliensis as food sources. In the second, an A. brasiliensis female was placed in each arena, with eggs of B. phoenicis and N. californicus as food sources. Adults of both predators were able to consume both types of eggs available as food sources, but they fed on considerably higher proportions of B. phoenicis than on eggs of the predator. Eggs of A. brasiliensis were not a suitable food source for N. californicus, which produced only 0.1 egg per female per day when only eggs of that species were present in the experimental unit. The results suggest that eggs of N. californicus were a suitable food source for A. brasiliensis, which oviposited 1.12 eggs per day, when only eggs of N. californicus were provided to the stigmaeid mite. The possible interactions among N. californicus, A. brasiliensis and B. phoenicis in citrus orchards are discussed. PMID:25524512

  1. Tapping into yeast diversity.

    PubMed

    Fay, Justin C

    2012-11-01

    Domesticated organisms demonstrate our capacity to influence wild species but also provide us with the opportunity to understand rapid evolution in the context of substantially altered environments and novel selective pressures. Recent advances in genetics and genomics have brought unprecedented insights into the domestication of many organisms and have opened new avenues for further improvements to be made. Yet, our ability to engineer biological systems is not without limits; genetic manipulation is often quite difficult. The budding yeast, Saccharomyces cerevisiae, is not only one of the most powerful model organisms, but is also the premier producer of fermented foods and beverages around the globe. As a model system, it entertains a hefty workforce dedicated to deciphering its genome and the function it encodes at a rich mechanistic level. As a producer, it is used to make leavened bread, and dozens of different alcoholic beverages, such as beer and wine. Yet, applying the awesome power of yeast genetics to understanding its origins and evolution requires some knowledge of its wild ancestors and the environments from which they were derived. A number of surprisingly diverse lineages of S. cerevisiae from both primeval and secondary forests in China have been discovered by Wang and his colleagues. These lineages substantially expand our knowledge of wild yeast diversity and will be a boon to elucidating the ecology, evolution and domestication of this academic and industrial workhorse. PMID:23281494

  2. Glutathione Production in Yeast

    NASA Astrophysics Data System (ADS)

    Bachhawat, Anand K.; Ganguli, Dwaipayan; Kaur, Jaspreet; Kasturia, Neha; Thakur, Anil; Kaur, Hardeep; Kumar, Akhilesh; Yadav, Amit

    Glutathione, ? -glutamyl-cysteinyl-glycine, is the most abundant non-protein thiol found in almost all eukaryotic cells (and in some prokaryotes). The tripeptide, which is synthesized non-ribosomally by the consecutive action of two soluble enzymes, is needed for carrying out numerous functions in the cell, most important of which is the maintenance of the redox buffer. The cycle of glutathione biosynthesis and degradation forms part of the ? -glutamyl cycle in most organisms although the latter half of the pathway has not been demonstrated in yeasts. Our current understanding of how glutathione levels are controlled at different levels in the cell is described. Several different routes and processes have been attempted to increase commercial production of glutathione using both yeast and bacteria. In this article we discuss the history of glutathione production in yeast. The current bottlenecks for increased glutathione production are presented based on our current understanding of the regulation of glutathione homeostasis, and possible strategies for overcoming these limitations for further enhancing and improving glutathione production are discussed

  3. A Common Caatinga Cactus, Pilosocereus gounellei, is an Important Ecotope of Wild Triatoma brasiliensis Populations in the Jaguaribe Valley of Northeastern Brazil

    PubMed Central

    Valença-Barbosa, Carolina; Lima, Marli M.; Sarquis, Otília; Bezerra, Claudia M.; Abad-Franch, Fernando

    2014-01-01

    Triatoma brasiliensis is the most important vector of Chagas disease in the Caatinga eco-region of northeastern Brazil. Wild T. brasiliensis populations have been reported only from rocky outcrops. However, this species frequently infests/re-infests houses in rock-free sedimentary lowlands. We therefore hypothesized that it should also occupy other natural ecotopes. We show that a common Caatinga cactus, Pilosocereus gounellei, locally known as xiquexique, often harbors T. brasiliensis breeding colonies apparently associated with rodents (n = 44 cacti, infestation rate = 47.7%, 157 bugs captured). Our findings suggest that infested cacti might be involved in house re-infestation by T. brasiliensis in the Caatinga region. PMID:24710611

  4. Disseminated Sporothrix brasiliensis Infection with Endocardial and Ocular Involvement in an HIV-Infected Patient

    PubMed Central

    Silva-Vergara, Mario León; de Camargo, Zoilo Pires; Silva, Patricia Ferreira; Abdalla, Michel Reis; Sgarbieri, Ricardo Nilsson; Rodrigues, Anderson Messias; dos Santos, Keila Cristina; Barata, Cristina Hueb; Ferreira-Paim, Kennio

    2012-01-01

    Disseminated sporotrichosis occurs in individuals with impaired cellular immunity, such as in cases of neoplasia, transplantation, diabetes, and especially, acquired immunodeficiency syndrome. This report presents a 32-year-old Brazilian human immunodeficiency virus (HIV)-infected patient who developed a protracted condition of disseminated sporotrichosis with endocarditis, bilateral endophthalmitis, and lymphatic involvement. He needed cardiac surgery to replace the mitral valve. Sporothrix brasiliensis isolates were recovered from cultures of subcutaneous nodules and mitral valve fragments. Species identification was based on classical and molecular methods. The patient received amphotericin B for 52 days and subsequently, oral itraconazole. He remains asymptomatic, and he is on maintenance therapy with itraconazole. Despite his positive clinical outcome, he developed bilateral blindness. To our knowledge, this case is the first report of endocarditis and endophthalmitis caused by S. brasiliensis. PMID:22403321

  5. Microsatellites for Carpotroche brasiliensis (Flacourtiaceae), a useful species for agroforestry and ecosystem conservation1

    PubMed Central

    Bittencourt, Flora; Alves, Jackeline S.; Gaiotto, Fernanda A.

    2015-01-01

    Premise of the study: We developed microsatellite markers for Carpotroche brasiliensis (Flacourtiaceae), a dioecious tree that is used as a food resource by midsize animals of the Brazilian fauna. Methods and Results: We designed 30 primer pairs using next-generation sequencing and classified 25 pairs as polymorphic. Observed heterozygosity ranged from 0.5 to 1.0, and expected heterozygosity ranged from 0.418 to 0.907. The combined probability of exclusion was greater than 0.999 and the combined probability of identity was less than 0.001, indicating that these microsatellites are appropriate for investigations of genetic structure, individual identification, and paternity testing. Conclusions: The developed molecular tools may contribute to future studies of population genetics, answering ecological and evolutionary questions regarding efficient conservation strategies for C. brasiliensis. PMID:26697275

  6. The isolation and composition of helical protein microfibrils from Hevea brasiliensis latex

    PubMed Central

    Audley, B. G.

    1966-01-01

    1. The microfibrils contained within the lutoid particles of Hevea brasiliensis latex obtained from young tissue have been isolated by methods based on low-speed centrifugation, isoelectric precipitation and gel filtration. 2. The isolated microfibrils behave as a single protein having an isoelectric point of about 4 as determined by paper electrophoresis. 3. The only components so far detected in the microfibrils are protein and possibly carbohydrate; nucleic acid appears to be absent. 4. The amino acid composition of the microfibril protein shows no unusual features. 5. In latex from the more mature laticiferous tissues of H. brasiliensis, the lutoid particles appear to be devoid of microfibrils or their protein decomposition products. ImagesPLATE 1Fig. 1.Fig. 5. PMID:5938659

  7. 21 CFR 172.896 - Dried yeasts.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) may be safely used in food provided the total folic acid content of the yeast does not exceed 0.04 milligram per gram of yeast (approximately 0.008 milligram of pteroyglutamic acid per gram of yeast)....

  8. Nocardia brasiliensis induces an immunosuppressive microenvironment that favors chronic infection in BALB/c mice.

    PubMed

    Rosas-Taraco, Adrian G; Perez-Liñan, Amira R; Bocanegra-Ibarias, Paola; Perez-Rivera, Luz I; Salinas-Carmona, Mario C

    2012-07-01

    Nocardia brasiliensis is an intracellular microorganism and the most common etiologic agent of actinomycetoma in the Americas. Several intracellular pathogens induce an immunosuppressive microenvironment through increases in CD4+ Foxp3+ regulatory T cells (Treg), thus downregulating other T-cell subpopulations and assuring survival in the host. In this study, we determined whether N. brasiliensis modulates T-lymphocyte responses and their related cytokine profiles in a murine experimental model. We also examined the relationship between N. brasiliensis immunomodulation and pathogenesis and bacterial survival. In early infection, Th17/Tc17 cells were increased at day 3 (P < 0.05) in footpad tissue and spleen. Treg subpopulations peaked at days 7 and 15 (P < 0.01) in the footpad and spleen, respectively. Transforming growth factor β1 (TGF-β1) and interleuki-10 (IL-10) are cytokines known for their immunosuppressive effects. During early and chronic infections, these cytokines were elevated with increased TGF-β1 levels from days 3 to 30 (P < 0.01) and sustained IL-10 expression throughout infection compared to uninfected mice. IL-6 production was increased at day 3 (P < 0.01), whereas gamma interferon (IFN-γ), IL-17A, and IL-23 levels were highest at day 15 postinfection (P < 0.01) when a decrease in the bacterial load (>1 log) was also observed (P < 0.05). After these changes, at 30 to 60 days postinfection, IFN-γ production was decreased, whereas the expression of anti-inflammatory cytokines and the bacterial load again increased (P < 0.05). The increment in Treg cells and the related cytokine profile correlated with reduced inflammation at day 15 (P < 0.05) in the footpad. We conclude that N. brasiliensis modulates the immune system to induce an immunosuppressive microenvironment that benefits its survival during the chronic stage of infection. PMID:22547544

  9. A note on the infection of Scomberomorus brasiliensis (Osteichthyes, Scombridae) by Kudoa sp. (Myxozoa: Multivalvulida).

    PubMed

    Eiras, J C; Lima, J T A X; Cruz, C F; Saraiva, A

    2014-08-01

    The infection of Scomberomorus brasiliensis by the myxozoan Kudoa sp. is reported. The parasites formed plasmodiae inside the skeletal muscle fibres. The spores were quadrate in apical view and bell-like shaped in lateral view, containing four equally sized more or less rounded polar capsules. No detrimental effects were observed in the host, namely muscle liquefaction. The importance of these parasites is discussed. PMID:25627380

  10. Nocardia brasiliensis Induces Formation of Foamy Macrophages and Dendritic Cells In Vitro and In Vivo

    PubMed Central

    Meester, Irene; Rosas-Taraco, Adrian Geovanni; Salinas-Carmona, Mario Cesar

    2014-01-01

    Foamy cells have been described in various infectious diseases, for example in actinomycetoma induced by Nocardia brasiliensis. These cells are generally considered to be macrophages, although they present dendritic cell (DC)-specific surface markers. In this study, we determined and confirmed the lineage of possible precursors of foamy cells in vitro and in vivo using an experimental actinomycetoma model in BALB/c mice. Bone marrow-derived macrophages (BMDM) or DC (BMDC) were infected in vitro with N. brasiliensis or labeled with carboxyfluorescein diacetate succinimidyl ester (CFSE). Both, macrophages and DC, differentiated into foamy cells after in vitro infection. CFSE-labeled BMDM or BMDC were tested for phagocytosis and CD11c/CD11b receptors markers expression before being transferred into the actinomycetoma lesion site of infected mice. In vivo studies showed that BMDM and BMDC were traced at the site where foamy cells are present in the experimental actinomycetoma. Interestingly, many of the transferred BMDM and BMDC were stained with the lipid-droplet fluorophore Nile Red. In conclusion, macrophages and DC cells can be differentiated into foamy cells in vitro and in vivo during N. brasiliensis infection. PMID:24936860

  11. Nocardia brasiliensis induces formation of foamy macrophages and dendritic cells in vitro and in vivo.

    PubMed

    Meester, Irene; Rosas-Taraco, Adrian Geovanni; Salinas-Carmona, Mario Cesar

    2014-01-01

    Foamy cells have been described in various infectious diseases, for example in actinomycetoma induced by Nocardia brasiliensis. These cells are generally considered to be macrophages, although they present dendritic cell (DC)-specific surface markers. In this study, we determined and confirmed the lineage of possible precursors of foamy cells in vitro and in vivo using an experimental actinomycetoma model in BALB/c mice. Bone marrow-derived macrophages (BMDM) or DC (BMDC) were infected in vitro with N. brasiliensis or labeled with carboxyfluorescein diacetate succinimidyl ester (CFSE). Both, macrophages and DC, differentiated into foamy cells after in vitro infection. CFSE-labeled BMDM or BMDC were tested for phagocytosis and CD11c/CD11b receptors markers expression before being transferred into the actinomycetoma lesion site of infected mice. In vivo studies showed that BMDM and BMDC were traced at the site where foamy cells are present in the experimental actinomycetoma. Interestingly, many of the transferred BMDM and BMDC were stained with the lipid-droplet fluorophore Nile Red. In conclusion, macrophages and DC cells can be differentiated into foamy cells in vitro and in vivo during N. brasiliensis infection. PMID:24936860

  12. Antioxidant Effects of Medicinal Mushrooms Agaricus brasiliensis and Ganoderma lucidum (Higher Basidiomycetes): Evidence from Animal Studies.

    PubMed

    Yurkiv, Borys; Wasser, Solomon P; Nevo, Eviatar; Sybirna, Nataliya O

    2015-01-01

    With diabetes mellitus and increased glucose concentrations, the mitochondria electron transport chain is disrupted, superoxide anions are overproduced, and oxidative stress develops in cells. Thus, preventing oxidative stress can produce a decrease in the antioxidant system activity and an increase in apoptosis in immune cells. The application of medicinal mushrooms is a new possible approach to diabetes mellitus treatment. Therefore, the aim of this work was to investigate the influence of administration of the medicinal mushrooms Agaricus brasiliensis and Ganoderma lucidum on antioxidant enzyme activity in rat leukocytes. Wistar outbred white rats were used in the study. Streptozotocin was intraperitoneally injected once at a dose of 50 mg/kg body weight. Mushroom preparations were orally administered at a dose of 1 g/kg/day for 2 weeks. This revealed that in diabetes mellitus, the level of antioxidant enzyme activity is significantly decreased compared with control values, whereas the levels of lipid peroxidation is increased; this manifested in an increase in the amount of thiobarbituric acid reactive substances (TBARS). The medicinal mushrooms' administration is accompanied by an increase in antioxidant enzyme activity to control values and is even higher in the case of A. brasiliensis administration when compared with the diabetic group. As for the indicators of lipid peroxidation under mushroom administration of A. brasiliensis and G. lucidum, we observed a significant decrease of TBARS levels compared with the diabetic group. Increased activity of antioxidant enzymes and reduction of TBARS level indicate pronounced antioxidant properties of studied mushrooms. PMID:26756186

  13. Morphometry, Bite-Force, and Paleobiology of the Late Miocene Caiman Purussaurus brasiliensis

    PubMed Central

    Aureliano, Tito; Ghilardi, Aline M.; Guilherme, Edson; Souza-Filho, Jonas P.; Cavalcanti, Mauro; Riff, Douglas

    2015-01-01

    Purussaurus brasiliensis thrived in the northwestern portion of South America during the Late Miocene. Although substantial material has been recovered since its early discovery, this fossil crocodilian can still be considered as very poorly understood. In the present work, we used regression equations based on modern crocodilians to present novel details about the morphometry, bite-force and paleobiology of this species. According to our results, an adult Purussaurus brasiliensis was estimated to reach around 12.5 m in length, weighing around 8.4 metric tons, with a mean daily food intake of 40.6 kg. It was capable of generating sustained bite forces of 69,000 N (around 7 metric tons-force). The extreme size and strength reached by this animal seems to have allowed it to include a wide range of prey in its diet, making it a top predator in its ecosystem. As an adult, it would have preyed upon large to very large vertebrates, and, being unmatched by any other carnivore, it avoided competition. The evolution of a large body size granted P. brasiliensis many advantages, but it may also have led to its vulnerability. The constantly changing environment on a large geological scale may have reduced its long-term survival, favoring smaller species more resilient to ecological shifts. PMID:25689140

  14. Bark harvesting systems of Drimys brasiliensis Miers in the Brazilian Atlantic rainforest.

    PubMed

    Mariot, Alexandre; Mantovani, Adelar; Reis, Maurício S dos

    2014-09-01

    Drimys brasiliensis Miers, locally known as cataia or casca-de-anta, is a native tree species of the Atlantic Rainforest. Its bark is harvested from natural populations. This study examined the recovery capacity of the bark of D. brasiliensis under different bark harvesting methods, as well as the influence of these approaches on its population dynamics and reproductive biology. While none of these treatments resulted in changes in phenological behavior or the rate of increase of diameter at breast height and tree height, the removal of wider bark strips resulted in lower rates of bark recovery and higher rates of insect attack and diseases. Accordingly, the results recommend using strips of bark 2 cm wide and 2 m long, with 4 cm between strips, for effective rates of bark regrowth and for lower susceptibility to insect attack and diseases. From these studies, we concluded that D. brasiliensis has a high potential for sustainable management of its natural populations, demonstrating the possibility of generating an important supplementary income for farmers and contributing to the use and conservation of the Atlantic Rainforest. PMID:25119732

  15. Morphometry, bite-force, and paleobiology of the late miocene caiman Purussaurus brasiliensis.

    PubMed

    Aureliano, Tito; Ghilardi, Aline M; Guilherme, Edson; Souza-Filho, Jonas P; Cavalcanti, Mauro; Riff, Douglas

    2015-01-01

    Purussaurus brasiliensis thrived in the northwestern portion of South America during the Late Miocene. Although substantial material has been recovered since its early discovery, this fossil crocodilian can still be considered as very poorly understood. In the present work, we used regression equations based on modern crocodilians to present novel details about the morphometry, bite-force and paleobiology of this species. According to our results, an adult Purussaurus brasiliensis was estimated to reach around 12.5 m in length, weighing around 8.4 metric tons, with a mean daily food intake of 40.6 kg. It was capable of generating sustained bite forces of 69,000 N (around 7 metric tons-force). The extreme size and strength reached by this animal seems to have allowed it to include a wide range of prey in its diet, making it a top predator in its ecosystem. As an adult, it would have preyed upon large to very large vertebrates, and, being unmatched by any other carnivore, it avoided competition. The evolution of a large body size granted P. brasiliensis many advantages, but it may also have led to its vulnerability. The constantly changing environment on a large geological scale may have reduced its long-term survival, favoring smaller species more resilient to ecological shifts. PMID:25689140

  16. Bioconcentration and bioaccumulation of metal in freshwater Neotropical fish Geophagus brasiliensis.

    PubMed

    Voigt, Carmen Lúcia; da Silva, Cleber Pinto; Doria, Halina Binde; Randi, Marco Antônio Ferreira; de Oliveira Ribeiro, Ciro Alberto; de Campos, Sandro Xavier

    2015-06-01

    From the concentration in water and sediments, bioconcentration and bioaccumulation of copper (Cu), manganese (Mn), zinc (Zn), iron (Fe), cobalt (Co), cadmium (Cd), chrome (Cr), silver (Ag), lead (Pb), nickel (Ni), aluminum (Al), and arsenic (As) were determined in the gills, liver, and muscles of Geophagus brasiliensis in the Alagados Reservoir, Ponta Grossa, Paraná, Brazil. Metals were quantified through AAS, and a study was carried out on the existing relations between metal and body weight, size, and genre of this species. The level of metal in the water of the reservoir was lower than the maximum set forth in the legislation, except for that of Cd and Fe. In sediments, Cu, Cd, Cr, and Ni presented concentrations above the threshold effect level (TEL). Pb and Cr were above the limits for the G. brasiliensis. The tendency of metals present in the muscles of G. brasiliensis was Al?>?Cu?>?Zn?>?Fe?>?Co?>?Mn?>?Cr?>?Ag?>?Ni?>?Pb?>?Cd?>?As. In the gills, it was Al?>?Fe?>?Zn?>?Mn?>?Co?>?Ag?>?Cr?>?Ni?>?Cu?>?As?>?Pb?>?Cd, and the liver presented Al?>?Cu?>?Zn?>?Co?>?Fe?>?Mn?>?Pb?>?Ag?>?Ni?>?Cr?>?As?>?Cd. The bioconcentration and bioaccumulation of metal in the tissues follow the global tendency liver?>?gills?>?muscle. The statistical analysis did not point to significant differences in the metal concentration and body weight, size, and gender of the species in the three tissues under analysis. PMID:25520205

  17. BIOSYNTHESIS OF YEAST CAROTENOIDS

    PubMed Central

    Simpson, Kenneth L.; Nakayama, T. O. M.; Chichester, C. O.

    1964-01-01

    Simpson, Kenneth L. (University of California, Davis), T. O. M. Nakayama, and C. O. Chichester. Biosynthesis of yeast carotenoids. J. Bacteriol. 88:1688–1694. 1964.—The biosynthesis of carotenoids was followed in Rhodotorula glutinis and in a new strain, 62-506. The treatment of the growing cultures by methylheptenone, or ionone, vapors permitted observations of the intermediates in the biosynthetic pathway. On the basis of concentration changes and accumulation in blocked pathways, the sequence of carotenoid formation is postulated as phytoene, phytofluene, ?-carotene, neurosporene, ?-zeacarotene, ?-carotene, torulin, a C40 aldehyde, and torularhodin. Torulin and torularhodin were established as the main carotenoids of 62-506. PMID:14240958

  18. Ethanol tolerance in yeasts.

    PubMed

    Casey, G P; Ingledew, W M

    1986-01-01

    It is now certain that the inherent ethanol tolerance of the Saccharomyces strain used is not the prime factor regulating the level of ethanol that can be produced in a high sugar brewing, wine, sake, or distillery fermentation. In fact, in terms of the maximum concentration that these yeasts can produce under batch (16 to 17% [v/v]) or fed-batch conditions, there is clearly no difference in ethanol tolerance. This is not to say, however, that under defined conditions there is no difference in ethanol tolerance among different Saccharomyces yeasts. This property, although a genetic determinant, is clearly influenced by many factors (carbohydrate level, wort nutrition, temperature, osmotic pressure/water activity, and substrate concentration), and each yeast strain reacts to each factor differently. This will indeed lead to differences in measured tolerance. Thus, it is extremely important that each of these be taken into consideration when determining "tolerance" for a particular set of fermentation conditions. The manner in which each alcohol-related industry has evolved is now known to have played a major role in determining traditional thinking on ethanol tolerance in Saccharomyces yeasts. It is interesting to speculate on how different our thinking on ethanol tolerance would be today if sake fermentations had not evolved with successive mashing and simultaneous saccharification and fermentation of rice carbohydrate, if distillers' worts were clarified prior to fermentation but brewers' wort were not, and if grape skins with their associated unsaturated lipids had not been an integral part of red wine musts. The time is now ripe for ethanol-related industries to take advantage of these findings to improve the economies of production. In the authors' opinion, breweries could produce higher alcohol beers if oxygenation (leading to unsaturated lipids) and "usable" nitrogen source levels were increased in high gravity worts. White wine fermentations could also, if desired, match the higher ethanol levels in red wines if oxygenation (to provide the unsaturated lipids deleted in part by the removal of the grape skins) were practiced and if care were given to assimilable nitrogen concentrations. This would hold true even at 10 to 14 degrees C, and the more rapid fermentations would maximize utilization of winery tankage.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:3533426

  19. Environmental controls in the water use patterns of a tropical cloud forest tree species, Drimys brasiliensis (Winteraceae).

    PubMed

    Eller, Cleiton B; Burgess, Stephen S O; Oliveira, Rafael S

    2015-04-01

    Trees from tropical montane cloud forest (TMCF) display very dynamic patterns of water use. They are capable of downwards water transport towards the soil during leaf-wetting events, likely a consequence of foliar water uptake (FWU), as well as high rates of night-time transpiration (Enight) during drier nights. These two processes might represent important sources of water losses and gains to the plant, but little is known about the environmental factors controlling these water fluxes. We evaluated how contrasting atmospheric and soil water conditions control diurnal, nocturnal and seasonal dynamics of sap flow in Drimys brasiliensis (Miers), a common Neotropical cloud forest species. We monitored the seasonal variation of soil water content, micrometeorological conditions and sap flow of D. brasiliensis trees in the field during wet and dry seasons. We also conducted a greenhouse experiment exposing D. brasiliensis saplings under contrasting soil water conditions to deuterium-labelled fog water. We found that during the night D. brasiliensis possesses heightened stomatal sensitivity to soil drought and vapour pressure deficit, which reduces night-time water loss. Leaf-wetting events had a strong suppressive effect on tree transpiration (E). Foliar water uptake increased in magnitude with drier soil and during longer leaf-wetting events. The difference between diurnal and nocturnal stomatal behaviour in D. brasiliensis could be attributed to an optimization of carbon gain when leaves are dry, as well as minimization of nocturnal water loss. The leaf-wetting events on the other hand seem important to D. brasiliensis water balance, especially during soil droughts, both by suppressing tree transpiration (E) and as a small additional water supply through FWU. Our results suggest that decreases in leaf-wetting events in TMCF might increase D. brasiliensis water loss and decrease its water gains, which could compromise its ecophysiological performance and survival during dry periods. PMID:25716877

  20. Nocardia brasiliensis cell wall lipids modulate macrophage and dendritic responses that favor development of experimental actinomycetoma in BALB/c mice.

    PubMed

    Trevino-Villarreal, J Humberto; Vera-Cabrera, Lucio; Valero-Guillén, Pedro L; Salinas-Carmona, Mario C

    2012-10-01

    Nocardia brasiliensis is a Gram-positive facultative intracellular bacterium frequently isolated from human actinomycetoma. However, the pathogenesis of this infection remains unknown. Here, we used a model of bacterial delipidation with benzine to investigate the role of N. brasiliensis cell wall-associated lipids in experimental actinomycetoma. Delipidation of N. brasiliensis with benzine resulted in complete abolition of actinomycetoma without affecting bacterial viability. Chemical analyses revealed that trehalose dimycolate and an unidentified hydrophobic compound were the principal compounds extracted from N. brasiliensis with benzine. By electron microscopy, the extracted lipids were found to be located in the outermost membrane layer of the N. brasiliensis cell wall. They also appeared to confer acid-fastness. In vitro, the extractable lipids from the N. brasiliensis cell wall induced the production of the proinflammatory cytokines interleukin-1β (IL-1β), IL-6, and CCL-2 in macrophages. The N. brasiliensis cell wall extractable lipids inhibited important macrophage microbicidal effects, such as tumor necrosis factor alpha (TNF-α) and nitric oxide (NO) production, phagocytosis, bacterial killing, and major histocompatibility complex class II (MHC-II) expression in response to gamma interferon (IFN-γ). In dendritic cells (DCs), N. brasiliensis cell wall-associated extractable lipids suppressed MHC-II, CD80, and CD40 expression while inducing tumor growth factor β (TGF-β) production. Immunization with delipidated N. brasiliensis induced partial protection preventing actinomycetoma. These findings suggest that N. brasiliensis cell wall-associated lipids are important for actinomycetoma development by inducing inflammation and modulating the responses of macrophages and DCs to N. brasiliensis. PMID:22851755

  1. Nocardia brasiliensis Cell Wall Lipids Modulate Macrophage and Dendritic Responses That Favor Development of Experimental Actinomycetoma in BALB/c Mice

    PubMed Central

    Trevino-Villarreal, J. Humberto; Vera-Cabrera, Lucio; Valero-Guillén, Pedro L.

    2012-01-01

    Nocardia brasiliensis is a Gram-positive facultative intracellular bacterium frequently isolated from human actinomycetoma. However, the pathogenesis of this infection remains unknown. Here, we used a model of bacterial delipidation with benzine to investigate the role of N. brasiliensis cell wall-associated lipids in experimental actinomycetoma. Delipidation of N. brasiliensis with benzine resulted in complete abolition of actinomycetoma without affecting bacterial viability. Chemical analyses revealed that trehalose dimycolate and an unidentified hydrophobic compound were the principal compounds extracted from N. brasiliensis with benzine. By electron microscopy, the extracted lipids were found to be located in the outermost membrane layer of the N. brasiliensis cell wall. They also appeared to confer acid-fastness. In vitro, the extractable lipids from the N. brasiliensis cell wall induced the production of the proinflammatory cytokines interleukin-1? (IL-1?), IL-6, and CCL-2 in macrophages. The N. brasiliensis cell wall extractable lipids inhibited important macrophage microbicidal effects, such as tumor necrosis factor alpha (TNF-?) and nitric oxide (NO) production, phagocytosis, bacterial killing, and major histocompatibility complex class II (MHC-II) expression in response to gamma interferon (IFN-?). In dendritic cells (DCs), N. brasiliensis cell wall-associated extractable lipids suppressed MHC-II, CD80, and CD40 expression while inducing tumor growth factor ? (TGF-?) production. Immunization with delipidated N. brasiliensis induced partial protection preventing actinomycetoma. These findings suggest that N. brasiliensis cell wall-associated lipids are important for actinomycetoma development by inducing inflammation and modulating the responses of macrophages and DCs to N. brasiliensis. PMID:22851755

  2. The Budding Yeast Nucleus

    PubMed Central

    Taddei, Angela; Schober, Heiko; Gasser, Susan M.

    2010-01-01

    The budding yeast nucleus, like those of other eukaryotic species, is highly organized with respect to both chromosomal sequences and enzymatic activities. At the nuclear periphery interactions of nuclear pores with chromatin, mRNA, and transport factors promote efficient gene expression, whereas centromeres, telomeres, and silent chromatin are clustered and anchored away from pores. Internal nuclear organization appears to be function-dependent, reflecting localized sites for tRNA transcription, rDNA transcription, ribosome assembly, and DNA repair. Recent advances have identified new proteins involved in the positioning of chromatin and have allowed testing of the functional role of higher-order chromatin organization. The unequal distribution of silent information regulatory factors and histone modifying enzymes, which arises in part from the juxtaposition of telomeric repeats, has been shown to influence chromatin-mediated transcriptional repression. Other localization events suppress unwanted recombination. These findings highlight the contribution budding yeast genetics and cytology have made to dissecting the functional role of nuclear structure. PMID:20554704

  3. Red yeast rice for dysipidemia.

    PubMed

    Shamim, Shariq; Al Badarin, Firas J; DiNicolantonio, James J; Lavie, Carl J; O'Keefe, James H

    2013-01-01

    Red yeast rice is an ancient Chinese food product that contains monacolins, chemical substances that are similar to statins in their mechanisms of action and lipid lowering properties. Several studies have found red yeast rice to be moderately effective at improving the lipid profile, particularly for lowering the low-density lipoprotein cholesterol levels. One large randomized controlled study from China found that red yeast rice significantly improved risk of major adverse cardiovascular events and overall survival in patients following myocardial infarction. Thus, red yeast rice is a potentially useful over-the-counter cholesterol-lowering agent. However, many red yeast rice formulations are non-standardized and unregulated food supplements, and there is a need for further research and regulation of production. PMID:24003656

  4. Brewer's yeast and sugarcane yeast as protein sources for dogs.

    PubMed

    Martins, M S; Sakomura, N K; Souza, D F; Filho, F O R; Gomes, M O S; Vasconcellos, R S; Carciofi, A C

    2014-10-01

    Brewer's yeast (BY), autolysed sugarcane yeast (ASCY) and integral sugar cane yeast (ISCY) were studied in two experiments as ingredients for dog diets. In the first experiment, 28 dogs were randomly assigned to four diets; one reference diet and three test diets containing 15% of BY, ASCY or ISCY and 85% of the reference diet (as-fed basis). The digestibilities of the yeasts were calculated by the substitution method. In the second experiment, 35 dogs were randomized to five diets with similar chemical composition but different levels of sugarcane yeast inclusion (0%, 7.5% ASCY, 15% ASCY, 7.5% ISCY and 15% ISCY). In both experiments, the coefficient of total tract apparent digestibility (CTTAD) of nutrients was determined through total collection of faeces. During experiment, two additional analyses of food palatability, nitrogen balance and urea postprandial responses were performed. The data were submitted to analysis of variance, and the means were compared by orthogonal or polynomial contrasts or Tukey's test (p < 0.05). In experiment 1, CTTAD of protein was lower for both sugarcane yeasts than for BY (p = 0.012), as was metabolizable energy content (p = 0.025). In experiment 2, a linear reduction in energy digestibility with ASCY inclusion (p = 0.05) was verified. Furthermore, faecal score and DM content were reduced with ISCY inclusion (p < 0.003). No effect of yeast inclusion on nitrogen balance or postprandial urea response was found. Also, the inclusion of 7.5% of ASCY or ISCY increased diet palatability (p < 0.01). Yeasts present adequate digestibility by dogs, but its effect on faecal formation needs to be considered. No clear advantage for the use of ASCY over ISCY was found. In conclusion, we find that sugarcane yeast is suitable for inclusion in dog food and can enhance the overall palatability of the diet. PMID:24304448

  5. Epidemiological and biological aspects on Ornithodoros brasiliensis (mouro tick), an argasidae tick only found on the highlands region of Rio Grande do Sul state, southern Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The soft tick Ornithodoros brasiliensis (Acari: Argasidae) is present in farms along the highlands of Rio Grande do Sul state in southern Brazil. Reports of human parasitism by O. brasiliensis drew the attention of local health authorities. A preliminary epidemiological survey was conducted to ident...

  6. Agriculturally important yeasts: Biological control of field and postharvest diseases using yeast antagonists, and yeasts as pathogens of plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two important agricultural aspects of yeasts, control of plant diseases through application of yeasts as the control agent, and yeasts that are plant pathogens are reviewed. Yeasts as biocontrol organisms are presented first, followed by a discussion of some of the more common plant pathogenic yeas...

  7. Lager yeast comes of age.

    PubMed

    Wendland, Jürgen

    2014-10-01

    Alcoholic fermentations have accompanied human civilizations throughout our history. Lager yeasts have a several-century-long tradition of providing fresh beer with clean taste. The yeast strains used for lager beer fermentation have long been recognized as hybrids between two Saccharomyces species. We summarize the initial findings on this hybrid nature, the genomics/transcriptomics of lager yeasts, and established targets of strain improvements. Next-generation sequencing has provided fast access to yeast genomes. Its use in population genomics has uncovered many more hybridization events within Saccharomyces species, so that lager yeast hybrids are no longer the exception from the rule. These findings have led us to propose network evolution within Saccharomyces species. This "web of life" recognizes the ability of closely related species to exchange DNA and thus drain from a combined gene pool rather than be limited to a gene pool restricted by speciation. Within the domesticated lager yeasts, two groups, the Saaz and Frohberg groups, can be distinguished based on fermentation characteristics. Recent evidence suggests that these groups share an evolutionary history. We thus propose to refer to the Saaz group as Saccharomyces carlsbergensis and to the Frohberg group as Saccharomyces pastorianus based on their distinct genomes. New insight into the hybrid nature of lager yeast will provide novel directions for future strain improvement. PMID:25084862

  8. Interaction Between Yeasts and Zinc

    NASA Astrophysics Data System (ADS)

    Nicola, Raffaele De; Walker, Graeme

    Zinc is an essential trace element in biological systems. For example, it acts as a cellular membrane stabiliser, plays a critical role in gene expression and genome modification and activates nearly 300 enzymes, including alcohol dehydrogenase. The present chapter will be focused on the influence of zinc on cell physiology of industrial yeast strains of Saccharomyces cerevisiae, with special regard to the uptake and subsequent utilisation of this metal. Zinc uptake by yeast is metabolism-dependent, with most of the available zinc translocated very quickly into the vacuole. At cell division, zinc is distributed from mother to daughter cells and this effectively lowers the individual cellular zinc concentration, which may become zinc depleted at the onset of the fermentation. Zinc influences yeast fermentative performance and examples will be provided relating to brewing and wine fermentations. Industrial yeasts are subjected to several stresses that may impair fermentation performance. Such stresses may also impact on yeast cell zinc homeostasis. This chapter will discuss the practical implications for the correct management of zinc bioavailability for yeast-based biotechnologies aimed at improving yeast growth, viability, fermentation performance and resistance to environmental stresses

  9. Lager Yeast Comes of Age

    PubMed Central

    2014-01-01

    Alcoholic fermentations have accompanied human civilizations throughout our history. Lager yeasts have a several-century-long tradition of providing fresh beer with clean taste. The yeast strains used for lager beer fermentation have long been recognized as hybrids between two Saccharomyces species. We summarize the initial findings on this hybrid nature, the genomics/transcriptomics of lager yeasts, and established targets of strain improvements. Next-generation sequencing has provided fast access to yeast genomes. Its use in population genomics has uncovered many more hybridization events within Saccharomyces species, so that lager yeast hybrids are no longer the exception from the rule. These findings have led us to propose network evolution within Saccharomyces species. This “web of life” recognizes the ability of closely related species to exchange DNA and thus drain from a combined gene pool rather than be limited to a gene pool restricted by speciation. Within the domesticated lager yeasts, two groups, the Saaz and Frohberg groups, can be distinguished based on fermentation characteristics. Recent evidence suggests that these groups share an evolutionary history. We thus propose to refer to the Saaz group as Saccharomyces carlsbergensis and to the Frohberg group as Saccharomyces pastorianus based on their distinct genomes. New insight into the hybrid nature of lager yeast will provide novel directions for future strain improvement. PMID:25084862

  10. Yeasts: From genetics to biotechnology

    SciTech Connect

    Russo, S.; Poli, G.; Siman-Tov, R.B.

    1995-12-31

    Yeasts have been known and used in food and alcoholic fermentations ever since the Neolithic Age. In more recent times, on the basis of their peculiar features and history, yeasts have become very important experimental models in both microbiological and genetic research, as well as the main characters in many fermentative production processes. In the last 40 years, advances in molecular biology and genetic engineering have made possible not only the genetic selection of organisms, but also the genetic modification of some of them, especially the simplest of them, such as bacteria and yeasts. These discoveries have led to the availability of new yeast strains fit to fulfill requests of industrial production and fermentation. Moreover, genetically modified and transformed yeasts have been constructed that are able to produce large amounts of biologically active proteins and enzymes. Thus, recombinant yeasts make it easier to produce drugs, biologically active products, diagnostics, and vaccines, by inexpensive and relatively simple techniques. Yeasts are going to become more and more important in the {open_quotes}biotechnological revolution{close_quotes} by virtue of both their features and their very long and safe use in human nutrition and industry. 175 refs., 4 figs., 6 tabs.

  11. Revisiting yeast trehalose metabolism.

    PubMed

    Eleutherio, Elis; Panek, Anita; De Mesquita, Joelma Freire; Trevisol, Eduardo; Magalhães, Rayne

    2015-08-01

    Establishing the function of trehalose in yeast cells has led us, over the years, through a long path-from simple energy storage carbohydrate, then a stabilizer and protector of membranes and proteins, through a safety valve against damage caused by oxygen radicals, up to regulator of the glycolytic path. In addition, trehalose biosynthesis has been proposed as a target for novel drugs against several pathogens. Since this pathway is entirely absent in mammalian cells and makes use of highly specific enzymes, trehalose metabolism might be an interesting target for the development of novel therapies. In this review, we want to address some recent points investigated about trehalose metabolism in Saccharomyces cerevisiae, focusing mainly on the mechanism by which this simple disaccharide protects against stress and on the enzymes involved in its synthesis and breakdown. We believe that these concepts are of great importance for medical and biotechnological applications. PMID:25209979

  12. BIOSYNTHESIS OF YEAST CAROTENOIDS.

    PubMed

    SIMPSON, K L; NAKAYAMA, T O; CHICHESTER, C O

    1964-12-01

    Simpson, Kenneth L. (University of California, Davis), T. O. M. Nakayama, and C. O. Chichester. Biosynthesis of yeast carotenoids. J. Bacteriol. 88:1688-1694. 1964.-The biosynthesis of carotenoids was followed in Rhodotorula glutinis and in a new strain, 62-506. The treatment of the growing cultures by methylheptenone, or ionone, vapors permitted observations of the intermediates in the biosynthetic pathway. On the basis of concentration changes and accumulation in blocked pathways, the sequence of carotenoid formation is postulated as phytoene, phytofluene, zeta-carotene, neurosporene, beta-zeacarotene, gamma-carotene, torulin, a C(40) aldehyde, and torularhodin. Torulin and torularhodin were established as the main carotenoids of 62-506. PMID:14240958

  13. Pulmonary infection in two sympatric lizards, Mabuya arajara (Scincidae) and Anolis brasiliensis (Polychrotidae) from a cloud forest in Chapada do Araripe, Ceará, Northeastern Brazil.

    PubMed

    Ribeiro, S C; Ferreira, F S; Brito, S V; Teles, D A; Ávila, R W; Almeida, W O; Anjos, L A; Guarnieri, M C

    2012-11-01

    The parameters of infection by lung parasites from two sympatric lizards, Mabuya arajara and Anolis brasiliensis, from the Atlantic Rainforest of the lower slope of Chapada do Araripe in Northeastern Brazil were analyzed between September, 2009 and July, 2010. A total of 202 lizards were collected. 125 specimens were from Mabuya arajara and 77 from Anolis brasiliensis. M. arajara was infected by the pentastomid Raillietiella mottae while A. brasiliensis was infected by the nematode Rhabdias sp., with an overall prevalence of 1.6% and 28.6%, respectively. The mean intensity of infection by Rhabdias sp. was 3.63 ± 2.58 (range 1-15). The body size and sex of lizards did not influence the intensity of infection by Rhabdias sp. The overall prevalence was also not different between males and females hosts in A. brasiliensis. Both Anolis brasiliensis and Mabuya arajara represent a new host to Rhabdias sp. and Raillietiella mottae, respectively. PMID:23295524

  14. Growth and mortalities of the pink-shrimp Farfantepenaeus brasiliensis Latreille, 1970 and F. paulensis Pérez-Farfante 1967 in Southeast Brazil.

    PubMed

    Leite, N O; Petrere, M

    2006-05-01

    From July, 1999 until July, 2001 data from the pink-shrimp Farfantepenaeus brasiliensis Latreille, 1970 and F. paulensis Pérez-Farfante, 1967 fishery were collected from trawling by the fishing fleet based in Santos/Guarujá-SP. Growth and mortalities of these species were studied. F. brasiliensis and F. paulensis have longevity of 2 years and growth estimates of L Infinity = 29.0 cm and k = 1.24 year-1 for F. brasiliensis and L Infinity = 27.5 cm and k = 1.34 year-1 for F. paulensis. Females reach bigger lengths than males in both species. Natural mortalities (M) were 1.80 and 1.90 year-1 and fishing mortalities (F) were 4.7 and 6.8 year-1 for F. brasiliensis and F. paulensis, respectively. Survival rates are S = 0.15% and 0.02% for F. brasiliensis and F. paulensis, respectively, which are usually low values for shrimps. PMID:16862308

  15. Lactic dehydrogenase virus infection enhances parasite egg production and inhibits eosinophil and mast cell responses in mice infected with the nematode Nippostrongylus brasiliensis.

    PubMed Central

    Morimoto, M; Yamada, M; Arizono, N; Hayashi, T

    1998-01-01

    The effects of lactic dehydrogenase virus (LDV) infection on the protective immune responses to the nematode Nippostrongylus brasiliensis were studied. Mice with chronic LDV infection showed significantly higher levels of parasite egg production than non-LDV-infected (control) mice after N. brasiliensis infection. Concurrent LDV infection also suppressed peripheral blood eosinophilia and the lung mastocytosis induced by this nematode. LDV infection showed higher expression levels of the interferon-gamma (IFN-gamma) mRNA in lymph nodes compared with control mice before N. brasiliensis infection. In addition, the IgG2a production in LDV-infected mice was higher than that in control mice before and after N. brasiliensis infection. These results suggest that LDV infection modulates protective immune responses against N. brasiliensis infection by the activation of T-helper type 1 cells. PMID:9659227

  16. 21 CFR 172.896 - Dried yeasts.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Dried yeasts. 172.896 Section 172.896 Food and... Multipurpose Additives § 172.896 Dried yeasts. Dried yeast (Saccharomyces cerevisiae and Saccharomyces fragilis) and dried torula yeast (Candida utilis) may be safely used in food provided the total folic...

  17. 21 CFR 172.896 - Dried yeasts.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Dried yeasts. 172.896 Section 172.896 Food and... Multipurpose Additives § 172.896 Dried yeasts. Dried yeast (Saccharomyces cerevisiae and Saccharomyces fragilis) and dried torula yeast (Candida utilis) may be safely used in food provided the total folic...

  18. 21 CFR 172.896 - Dried yeasts.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Dried yeasts. 172.896 Section 172.896 Food and... Multipurpose Additives § 172.896 Dried yeasts. Dried yeast (Saccharomyces cerevisiae and Saccharomyces fragilis) and dried torula yeast (Candida utilis) may be safely used in food provided the total folic...

  19. 21 CFR 172.896 - Dried yeasts.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Dried yeasts. 172.896 Section 172.896 Food and... Multipurpose Additives § 172.896 Dried yeasts. Dried yeast (Saccharomyces cerevisiae and Saccharomyces fragilis) and dried torula yeast (Candida utilis) may be safely used in food provided the total folic...

  20. Biosorption of copper by yeasts.

    PubMed

    Junghans, K; Straube, G

    1991-01-01

    The ability to accumulate copper from aqueous solutions was determined with different yeast species. Yeast cells did not show any significant differences in process kinetics. The uptake was very fast and was influenced by environmental factors. The metal-accumulating capacity differed among the tested strains. The yeast Candida tropicalis and Pichia guilliermondii were chosen for extensive research. Cells of the stationary growth phase were able to adsorb a high amount of copper. The uptake capacity decreased with increasing biomass concentration. Copper adsorption obeyed the Freundlich isotherm. Optimal pH range was between 5 and 7. The biomass could be used repeatedly for biosorption after desorption by mineral acids. PMID:1777357

  1. Molybdate induces thermotolerance in yeast.

    PubMed

    Tiligada, E; Miligkos, V; Ypsilantis, E; Papamichael, K; Delitheos, A

    1999-08-01

    Application of a mild heat pretreatment, performed by shifting cells from 27 degrees C to 37 degrees C led to the protection of yeast cells from death due to a subsequent extreme heat shock at 53 degrees C. The presence of cycloheximide inhibited this induction of thermotolerance, indicating the involvement of de novo protein. The phosphatase inhibitor sodium molybdate induced thermotolerance to the non-pretreated yeast cells. This induction of thermotolerance did not seem to depend upon de novo protein synthesis. Thus, acquisition of thermotolerance in yeast may involve a number of cellular mechanisms depending on the conditions the organism encounters at any particular time. PMID:10499293

  2. Effects of polysaccharide from fruiting bodies of Agaricus bisporus, Agaricus brasiliensis, and Phellinus linteus on alcoholic liver injury.

    PubMed

    Uyanoglu, Mustafa; Canbek, Mediha; van Griensven, Leo J L D; Yamac, Mustafa; Senturk, Hakan; Kartkaya, Kaz?m; Oglakc?, Aysegul; Turgak, Ozge; Kanbak, Gungor

    2014-06-01

    In the present study, the curative effects of crude polysaccharides (PSs) from mushrooms on the symptoms of alcoholic liver injury were investigated. PSs from Agaricus bisporus, Agaricus brasiliensis, and Phellinus linteus fruiting bodies were administered by gavage at levels of 100?mg per kg body weight per day for 7?d after the onset of the disease. The caspase-3 activity, mitochondrial membrane potential, mitochondrial outer membrane integrity of the liver tissues of sacrificed rats, and the serum alanine aminotransferase (ALT) levels were determined. In addition, light and transmission electron microscope (TEM) studies were performed for histopathological and cytological evaluations on liver sections. PSs from A. brasiliensis decreased ALT level and mitochondrial membrane potential and increased the outer membrane integrity; microscopic examinations also revealed normal hepatocytes and tissue. On the basis of our data, it can be argued that crude PSs from Agaricus brasiliensis have therapeutic potential for alcoholic liver injury. PMID:24392995

  3. Marine yeast isolation and industrial application

    PubMed Central

    Zaky, Abdelrahman Saleh; Tucker, Gregory A; Daw, Zakaria Yehia; Du, Chenyu

    2014-01-01

    Over the last century, terrestrial yeasts have been widely used in various industries, such as baking, brewing, wine, bioethanol and pharmaceutical protein production. However, only little attention has been given to marine yeasts. Recent research showed that marine yeasts have several unique and promising features over the terrestrial yeasts, for example higher osmosis tolerance, higher special chemical productivity and production of industrial enzymes. These indicate that marine yeasts have great potential to be applied in various industries. This review gathers the most recent techniques used for marine yeast isolation as well as the latest applications of marine yeast in bioethanol, pharmaceutical and enzyme production fields. PMID:24738708

  4. Differences in cell morphometry, cell wall topography and gp70 expression correlate with the virulence of Sporothrix brasiliensis clinical isolates.

    PubMed

    Castro, Rafaela A; Kubitschek-Barreira, Paula H; Teixeira, Pedro A C; Sanches, Glenda F; Teixeira, Marcus M; Quintella, Leonardo P; Almeida, Sandro R; Costa, Rosane O; Camargo, Zoilo P; Felipe, Maria S S; de Souza, Wanderley; Lopes-Bezerra, Leila M

    2013-01-01

    Sporotrichosis is a chronic infectious disease affecting both humans and animals. For many years, this subcutaneous mycosis had been attributed to a single etiological agent; however, it is now known that this taxon consists of a complex of at least four pathogenic species, including Sporothrix schenckii and Sporothrix brasiliensis. Gp70 was previously shown to be an important antigen and adhesin expressed on the fungal cell surface and may have a key role in immunomodulation and host response. The aim of this work was to study the virulence, morphometry, cell surface topology and gp70 expression of clinical isolates of S. brasiliensis compared with two reference strains of S. schenckii. Several clinical isolates related to severe human cases or associated with the Brazilian zoonotic outbreak of sporotrichosis were genotyped and clustered as S. brasiliensis. Interestingly, in a murine subcutaneous model of sporotrichosis, these isolates showed a higher virulence profile compared with S. schenckii. A single S. brasiliensis isolate from an HIV-positive patient not only showed lower virulence but also presented differences in cell morphometry, cell wall topography and abundant gp70 expression compared with the virulent isolates. In contrast, the highly virulent S. brasiliensis isolates showed reduced levels of cell wall gp70. These observations were confirmed by the topographical location of the gp70 antigen using immunoelectromicroscopy in both species. In addition, the gp70 molecule was sequenced and identified using mass spectrometry, and the sequenced peptides were aligned into predicted proteins using Blastp with the S. schenckii and S. brasiliensis genomes. PMID:24116065

  5. Microsatellite marker development for the rubber tree (Hevea brasiliensis): characterization and cross-amplification in wild Hevea species

    PubMed Central

    2012-01-01

    Background The rubber tree (Hevea brasiliensis) is native to the Amazon region and it is the major source of natural rubber in the world. Rubber tree breeding is time-consuming and expensive. However, molecular markers such as microsatellites can reduce the time required for these programs. This study reports new genomic microsatellite markers developed and characterized in H. brasiliensis and the evaluation of their transferability to other Hevea species. Findings We constructed di- and trinucleotide-enriched libraries. From these two libraries, 153 primer pairs were designed and initially evaluated using 9 genotypes of H. brasiliensis. A total of 119 primer pairs had a good amplification product, 90 of which were polymorphic. We chose 46 of the polymorphic markers and characterized them in 36 genotypes of H. brasiliensis. The expected and observed heterozygosities ranged from 0.1387 to 0.8629 and 0.0909 to 0.9167, respectively. The polymorphism information content (PIC) values ranged from 0.097 to 0.8339, and the mean number of alleles was 6.4 (2–17). These 46 microsatellites were also tested in 6 other Hevea species. The percentage of transferability ranged from 82% to 87%. Locus duplication was found in H. brasiliensis and also in 5 of other species in which transferability was tested. Conclusions This study reports new microsatellite markers for H. brasiliensis that can be used for genetic linkage mapping, quantitative trait loci identification and marker- assisted selection. The high percentage of transferability may be useful in the evaluations of genetic variability and to monitor introgression of genetic variability from different Hevea species into breeding programs. PMID:22731927

  6. First report on the diagnosis and treatment of encephalic and urinary paracoccidioidomycosis in a cat.

    PubMed

    Gonzalez, Juan F; Montiel, Nestor A; Maass, Rodrigo L

    2010-08-01

    A male Persian cat was presented with persistent fever, anorexia, weakness, hypopyon, nystagmus, and intention tremors. The hemogram showed severe neutropenia and laboratory analysis on cerebrospinal fluid (CSF) smears revealed abundant yeast cells compatible with Paracoccidioides brasiliensis. Urinalysis demonstrated persistent funguria and an increased urine protein-to-creatinine ratio (UPC) in addition to mild azotemia. Long-term therapy with oral fluconazole was effective in controlling the nervous system signs. Funguria was resolved with subcutaneous administration of diluted amphotericin B in a large volume of saline solution for a period of 12 weeks during the second year after initial diagnosis. Throughout 5 years of treatment, no adverse effects were observed and tolerance to the drugs was normal. Due to development of progressive uremic syndrome the animal was euthanased. To the best of our knowledge, this report is the first clinical case described of a nervous and urinary system infection caused by the P brasiliensis in a cat. PMID:20471880

  7. Red Yeast Rice: An Introduction

    MedlinePLUS

    ... as certain cholesterol-lowering drugs, and some may contain a potentially harmful contaminant. This fact sheet provides ... information. Key Facts Some red yeast rice products contain substantial amounts of monacolin K, which is chemically ...

  8. The Yeast Sphingolipid Signaling Landscape

    PubMed Central

    Montefusco, David J.; Matmati, Nabil

    2014-01-01

    Sphingolipids are recognized as signaling mediators in a growing number of pathways, and represent potential targets to address many diseases. The study of sphingolipid signaling in yeast has created a number of breakthroughs in the field, and has the potential to lead future advances. The aim of this article is to provide an inclusive view of two major frontiers in yeast sphingolipid signaling. In the first section, several key studies in the field of sphingolipidomics are consolidated to create a yeast sphingolipidome that ranks nearly all known sphingolipid species by their level in a resting yeast cell. The second section presents an overview of most known phenotypes identified for sphingolipid gene mutants, presented with the intention of illuminating not yet discovered connections outside and inside of the field. PMID:24220500

  9. Diet and helminths of Enyalius brasiliensis (Lacertilia, Iguania, Leiosauridae) in an Atlantic Rainforest remnant in southeastern Brazil.

    PubMed

    Dorigo, T A; Maia-Carneiro, T; Almeida-Gomes, M; Siqueira, C C; Vrcibradic, D; Van Sluys, M; Rocha, C F D

    2014-02-01

    Our study aimed to add information about the diet and endoparasites of Enyalius brasiliensis from an Atlantic Rainforest remnant in the state of Rio de Janeiro, southeastern Brazil. Regarding diet, E. brasiliensis consumed arthropods, with caterpillars and beetles being the most important preys. Regarding helminth parasites, overall prevalence was low (9.5%), with 238 nematodes of the genus Physaloptera found in the stomach of one specimen and one nematode of the genus Rhabdias inside the lung of another. Our results corroborate the observations of previous studies that indicate that lizards of the genus Enyalius tend to feed mainly on relatively large-bodied arthropods and to harbour depauperate endoparasite fauna. PMID:25055102

  10. Modest efficacy of voriconazole against murine infections by Sporothrix schenckii and lack of efficacy against Sporothrix brasiliensis.

    PubMed

    Fernández-Silva, Fabiola; Capilla, Javier; Mayayo, Emilio; Guarro, Josep

    2014-02-01

    The efficacy of voriconazole (VRC) was evaluated against two strains of each of the two most common species causing sporotrichosis, Sporothrix schenckii sensu stricto and Sporothrix brasiliensis, using a murine model of disseminated infection. Voriconazole was administered at doses of 20 or 40 mg kg(-1) per day by gavage. The drug showed some efficacy, especially at 40 mg kg(-1) per day, in prolonging the survival and reducing fungal load in spleen and liver in mice infected with S. schenckii, whereas in animals infected with S. brasiliensis the drug did not work. PMID:23879298

  11. Assembly and Analysis of Differential Transcriptome Responses of Hevea brasiliensis on Interaction with Microcyclus ulei.

    PubMed

    Hurtado Páez, Uriel Alonso; García Romero, Ibonne Aydee; Restrepo Restrepo, Silvia; Aristizábal Gutiérrez, Fabio Ancizar; Montoya Castaño, Dolly

    2015-01-01

    Natural rubber (Hevea brasiliensis) is a tropical tree used commercially for the production of latex, from which 40,000 products are generated. The fungus Microcyclus ulei infects this tree, causing South American leaf blight (SALB) disease. This disease causes developmental delays and significant crop losses, thereby decreasing the production of latex. Currently several groups are working on obtaining clones of rubber tree with durable resistance to SALB through the use of extensive molecular biology techniques. In this study, we used a secondary clone that was resistant to M. ulei isolate GCL012. This clone, FX 3864 was obtained by crossing between clones PB 86 and B 38 (H. brasiliensis x H. brasiliensis). RNA-Seq high-throughput sequencing technology was used to analyze the differential expression of the FX 3864 clone transcriptome at 0 and 48 h post infection (hpi) with the M. ulei isolate GCL012. A total of 158,134,220 reads were assembled using the de novo assembly strategy to generate 90,775 contigs with an N50 of 1672. Using a reference-based assembly, 76,278 contigs were generated with an N50 of 1324. We identified 86 differentially expressed genes associated with the defense response of FX 3864 to GCL012. Seven putative genes members of the AP2/ERF ethylene (ET)-dependent superfamily were found to be down-regulated. An increase in salicylic acid (SA) was associated with the up-regulation of three genes involved in cell wall synthesis and remodeling, as well as in the down-regulation of the putative gene CPR5. The defense response of FX 3864 against the GCL012 isolate was associated with the antagonistic SA, ET and jasmonic acid (JA) pathways. These responses are characteristic of plant resistance to biotrophic pathogens. PMID:26287380

  12. In Vivo Activity of the Benzothiazinones PBTZ169 and BTZ043 against Nocardia brasiliensis

    PubMed Central

    González-Martínez, Norma Alejandra; Lozano-Garza, Hector Gerardo; Castro-Garza, Jorge; De Osio-Cortez, Alexandra; Vargas-Villarreal, Javier; Cavazos-Rocha, Norma; Ocampo-Candiani, Jorge; Makarov, Vadim; Cole, Stewart T.; Vera-Cabrera, Lucio

    2015-01-01

    Background Mycetoma is a neglected, chronic, and deforming infectious disease caused by fungi and actinomycetes. In Mexico, N. brasiliensis is the predominant etiologic agent. Therapeutic alternatives are necessary because the current drug regimens have several disadvantages. Benzothiazinones (BTZ) are a new class of candidate drugs that inhibit decaprenyl-phosphoribose-epimerase (DprE1), an essential enzyme involved in the cell wall biosynthesis of Corynebacterineae. Methodology/Principal findings In this study, the in vitro activity of the next generation BTZ, PBTZ169, was tested against thirty Nocardia brasiliensis isolates. The MIC50 and MIC90 values for PBTZ169 were 0.0075 and 0.03 μg/mL, respectively. Because Nocardia is a potential intracellular bacterium, a THP-1 macrophage monolayer was infected with N. brasiliensis HUJEG-1 and then treated with PBTZ169, resulting in a decrease in the number of colony-forming units (CFUs) at a concentration of 0.25X the in vitro value. The in vivo activity was evaluated after infecting female BALB/c mice in the right hind food-pad. After 6 weeks, treatment was initiated with PBTZ169 and its activity was compared with the first generation compound, BTZ043. Both BTZ compounds were administered at 100 mg/kg twice daily by gavage, and sulfamethoxazole/trimethoprim (SXT), at 100 mg/kg sulfamethoxazole, was used as a positive control. After 22 weeks of therapy, only PBTZ169 and SXT displayed statistically significant activity. Conclusion These results indicate that DprE1 inhibitors may be useful for treating infections of Nocardia and may therefore be active against other actinomycetoma agents. We must test combinations of these compounds with other antimicrobial agents, such as linezolid, tedizolid or SXT, that have good to excellent in vivo activity, as well as new DprE1 inhibitors that can achieve higher plasma levels. PMID:26474057

  13. Assembly and Analysis of Differential Transcriptome Responses of Hevea brasiliensis on Interaction with Microcyclus ulei

    PubMed Central

    Restrepo Restrepo, Silvia; Aristizábal Gutiérrez, Fabio Ancizar; Montoya Castaño, Dolly

    2015-01-01

    Natural rubber (Hevea brasiliensis) is a tropical tree used commercially for the production of latex, from which 40,000 products are generated. The fungus Microcyclus ulei infects this tree, causing South American leaf blight (SALB) disease. This disease causes developmental delays and significant crop losses, thereby decreasing the production of latex. Currently several groups are working on obtaining clones of rubber tree with durable resistance to SALB through the use of extensive molecular biology techniques. In this study, we used a secondary clone that was resistant to M. ulei isolate GCL012. This clone, FX 3864 was obtained by crossing between clones PB 86 and B 38 (H. brasiliensis x H. brasiliensis). RNA-Seq high-throughput sequencing technology was used to analyze the differential expression of the FX 3864 clone transcriptome at 0 and 48 h post infection (hpi) with the M. ulei isolate GCL012. A total of 158,134,220 reads were assembled using the de novo assembly strategy to generate 90,775 contigs with an N50 of 1672. Using a reference-based assembly, 76,278 contigs were generated with an N50 of 1324. We identified 86 differentially expressed genes associated with the defense response of FX 3864 to GCL012. Seven putative genes members of the AP2/ERF ethylene (ET)-dependent superfamily were found to be down-regulated. An increase in salicylic acid (SA) was associated with the up-regulation of three genes involved in cell wall synthesis and remodeling, as well as in the down-regulation of the putative gene CPR5. The defense response of FX 3864 against the GCL012 isolate was associated with the antagonistic SA, ET and jasmonic acid (JA) pathways. These responses are characteristic of plant resistance to biotrophic pathogens. PMID:26287380

  14. Simulating Population Genetics of Pathogen Vectors in Changing Landscapes: Guidelines and Application with Triatoma brasiliensis

    PubMed Central

    Rebaudo, Francois; Costa, Jane; Almeida, Carlos E.; Silvain, Jean-Francois; Harry, Myriam; Dangles, Olivier

    2014-01-01

    Background Understanding the mechanisms that influence the population dynamics and spatial genetic structure of the vectors of pathogens infecting humans is a central issue in tropical epidemiology. In view of the rapid changes in the features of landscape pathogen vectors live in, this issue requires new methods that consider both natural and human systems and their interactions. In this context, individual-based model (IBM) simulations represent powerful yet poorly developed approaches to explore the response of pathogen vectors in heterogeneous social-ecological systems, especially when field experiments cannot be performed. Methodology/Principal Findings We first present guidelines for the use of a spatially explicit IBM, to simulate population genetics of pathogen vectors in changing landscapes. We then applied our model with Triatoma brasiliensis, originally restricted to sylvatic habitats and now found in peridomestic and domestic habitats, posing as the most important Trypanosoma cruzi vector in Northeastern Brazil. We focused on the effects of vector migration rate, maximum dispersal distance and attraction by domestic habitat on T. brasiliensis population dynamics and spatial genetic structure. Optimized for T. brasiliensis using field data pairwise fixation index (FST) from microsatellite loci, our simulations confirmed the importance of these three variables to understand vector genetic structure at the landscape level. We then ran prospective scenarios accounting for land-use change (deforestation and urbanization), which revealed that human-induced land-use change favored higher genetic diversity among sampling points. Conclusions/Significance Our work shows that mechanistic models may be useful tools to link observed patterns with processes involved in the population genetics of tropical pathogen vectors in heterogeneous social-ecological landscapes. Our hope is that our study may provide a testable and applicable modeling framework to a broad community of epidemiologists for formulating scenarios of landscape change consequences on vector dynamics, with potential implications for their surveillance and control. PMID:25102068

  15. Yeasts preservation: alternatives for lyophilisation.

    PubMed

    Nyanga, Loveness K; Nout, Martinus J R; Smid, Eddy J; Boekhout, Teun; Zwietering, Marcel H

    2012-11-01

    The aim of the study was to compare the effect of two low-cost, low technology traditional methods for drying starter cultures with standard lyophilisation. Lyophilised yeast cultures and yeast cultures preserved in dry rice cakes and dry plant fibre strands were examined for viable cell counts during 6 months storage at 4 and 25 °C. None of the yeast cultures showed a significant loss in viable cell count during 6 months of storage at 4 °C upon lyophilisation and preservation in dry rice cakes. During storage at 25 °C in the dark, yeast cultures preserved in dry rice cakes, and lyophilised cultures of Saccharomyces cerevisiae and Issatchenkia orientalis showed no significant loss of viable cells up to 4 months of storage. Yeast cultures preserved in dry plant fibre strands had the greatest loss of viable count during the 6 months of storage at 25 °C. Preservation of yeasts cultures in dry rice cakes provided better survival during storage at 4 °C than lyophilisation. The current study demonstrated that traditional methods can be useful and effective for starter culture preservation in small-scale, low-tech applications. PMID:22806747

  16. Study of amyloids using yeast

    PubMed Central

    Wickner, Reed B.; Kryndushkin, Dmitry; Shewmaker, Frank; McGlinchey, Ryan; Edskes, Herman K.

    2012-01-01

    Summary Saccharomyces cerevisiae has been a useful model organism in such fields as the cell cycle, regulation of transcription, protein trafficking and cell biology, primarily because of its ease of genetic manipulation. This is no less so in the area of amyloid studies. The endogenous yeast amyloids described to date include prions, infectious proteins (Table 1), and some cell wall proteins (1). and amyloids of humans and a fungal prion have also been studied using the yeast system. Accordingly, the emphasis of this chapter will be on genetic, biochemical, cell biological and physical methods particularly useful in the study of yeast prions and other amyloids studied in yeast. We limit our description of these methods to those aspects which have been most useful in studying yeast prions, citing more detailed expositions in the literature. Volumes on yeast genetics methods (2–4), and on amyloids and prions (5, 6) are useful, and Masison has edited a volume of Methods on “Identification, analysis and characterization of fungal prions” which covers some of this territory (7). We also outline some useful physical methods, pointing the reader to more extensive and authoratative descriptions. PMID:22528100

  17. Biotechnological Applications of Dimorphic Yeasts

    NASA Astrophysics Data System (ADS)

    Doiphode, N.; Joshi, C.; Ghormade, V.; Deshpande, M. V.

    The dimorphic yeasts have the equilibrium between spherical growth (budding) and polarized (hyphal or pseudohyphal tip elongation) which can be triggered by change in the environmental conditions. The reversible growth phenomenon has made dimorphic yeasts as an useful model to understand fungal evolution and fungal differentiation, in general. In nature dimorphism is clearly evident in plant and animal fungal pathogens, which survive and most importantly proliferate in the respective hosts. However, number of organisms with no known pathogenic behaviour also show such a transition, which can be exploited for the technological applications due to their different biochemical make up under different morphologies. For instance, chitin and chitosan production using dimorphic Saccharomyces, Mucor, Rhizopus and Benjaminiella, oil degradation and biotransformation with yeast-form of Yarrowia species, bioremediation of organic pollutants, exopolysac-charide production by yeast-phase of Aureobasidium pullulans, to name a few. Myrothecium verrucaria can be used for seed dressing in its yeast form and it produces a mycolytic enzyme complex in its hyphal-form for the biocontrol of fungal pathogens, while Beauveria bassiana and other entomopathogens kill the insect pest by producing yeast- like cells in the insect body. The form-specific expression of protease, chitinase, lipase, ornithine decarboxylase, glutamate dehydrogenases, etc. make Benjaminiella poitrasii, Basidiobolus sp., and Mucor rouxii strains important in bioremediation, nanobiotechnology, fungal evolution and other areas.

  18. Metabolic regulation of yeast

    NASA Astrophysics Data System (ADS)

    Fiechter, A.

    1982-12-01

    Metabolic regulation which is based on endogeneous and exogeneous process variables which may act constantly or time dependently on the living cell is discussed. The observed phenomena of the regulation are the result of physical, chemical, and biological parameters. These parameters are identified. Ethanol is accumulated as an intermediate product and the synthesis of biomass is reduced. This regulatory effect of glucose is used for the aerobic production of ethanol. Very high production rates are thereby obtained. Understanding of the regulation mechanism of the glucose effect has improved. In addition to catabolite repression, several other mechanisms of enzyme regulation have been described, that are mostly governed by exogeneous factors. Glucose also affects the control of respiration in a third class of yeasts which are unable to make use of ethanol as a substrate for growth. This is due to the lack of any anaplerotic activity. As a consequence, diauxic growth behavior is reduced to a one-stage growth with a drastically reduced cell yield. The pulse chemostat technique, a systematic approach for medium design is developed and medium supplements that are essential for metabolic control are identified.

  19. Yeast mitochondrial transcriptomics.

    PubMed

    Garcia, Mathilde; Darzacq, Xavier; Devaux, Frederic; Singer, Robert H; Jacq, Claude

    2007-01-01

    Although 30 years ago it was strongly suggested that some cytoplasmic ribosomes are bound to the surface of yeast mitochondria, the mechanisms and the raison d'être of this process are not understood. For instance, it is not perfectly known which of the several hundred nuclearly encoded genes have to be translated to the mitochondrial vicinity to guide the import of the corresponding proteins. One can take advantage of several modern methods to address a number of aspects of the site-specific translation process of messenger ribonucleic acid (mRNA) coding for proteins imported into mitochondria. Three complementary approaches are presented to analyze the spatial distribution of mRNAs coding for proteins imported into mitochondria. Starting from biochemical purifications of mitochondria-bound polysomes, we describe a genomewide approach to classify all the cellular mRNAs according to their physical proximity with mitochondria; we also present real-time quantitative reverse transcription polymerase chain reaction monitoring of mRNA distribution to provide a quantified description of this localization. Finally, a fluorescence microscopy approach on a single living cell is described to visualize the in vivo localization of mRNAs involved in mitochondria biogenesis. PMID:18314748

  20. Are Members of the Triatoma brasiliensis (Hemiptera, Reduviidae) Species Complex Able to Alter the Biology and Virulence of a Trypanosoma cruzi Strain?

    PubMed

    Costa, J; Araújo, C A C; Freitas, C A V; Borges-Pereira, J

    2015-04-01

    Trypanosoma cruzi is the causative agent of Chagas disease, transmitted to humans and mammals by blood-sucking hemipteran insects belonging to the Triatominae subfamily. The two main genotypes of T. cruzi (TcI and TcII) differ in many characteristics concerning their genetic profile. Despite the extensive literature on vectors and the etiologic agent, several interactive aspects between these two elements of Chagas disease are still waiting to be further clarified. Here, biological and histological features resulting from the interaction between Albino Swiss mice and T. cruzi isolate PB913 after passages through vectors of the Triatoma brasiliensis species complex were evaluated. Comparing the four members of the T. brasiliensis species complex-Triatoma brasiliensis brasiliensis Neiva, Triatoma brasiliensis macromelasoma Galvão, Triatoma melanica Neiva & Lent, and Triatoma juazeirensis Costa & Felix-no significant differences in parasitemia of the infected mice were observed. At 20 days post-infection, the highest number of parasites was observed in the group of mice that were infected with parasites obtained from T. b. macromelasoma. Tropism of the parasites to different organs such as heart, bladder, and skeletal muscles followed by inflammatory cell infiltrates was observed with quantitative and qualitative differences. Even though the four members of the T. brasiliensis species complex differ in their geographical distribution, morphology, biology, ecology, and genetics, no significant influence on the parasitemia of the T. cruzi PB913 isolate was detected. After evaluation of the tissue samples, a higher pathogenicity of parasites obtained from T. b. brasiliensis was noticeable. PMID:26013138

  1. Systemic increased immune response to Nocardia brasiliensis co-exists with local immunosuppressive microenvironment.

    PubMed

    Salinas-Carmona, Mario Cesar; Rosas-Taraco, Adrian Geovanni; Welsh, Oliverio

    2012-10-01

    Human diseases produced by pathogenic actinomycetes are increasing because they may be present as opportunistic infections. Some of these microbes cause systemic infections associated with immunosuppressive conditions, such as chemotherapy for cancer, immunosuppressive therapy for transplant, autoimmune conditions, and AIDS; while others usually cause localized infection in immunocompetent individuals. Other factors related to this increase in incidence are: antibiotic resistance, not well defined taxonomy, and a delay in isolation and identification of the offending microbe. Examples of these infections are systemic disease and brain abscesses produced by Nocardia asteroides or the located disease by Nocardia brasiliensis, named actinomycetoma. During the Pathogenic Actinomycetes Symposium of the 16th International Symposium on Biology of Actinomycetes (ISBA), held in Puerto Vallarta, Mexico, several authors presented recent research on the mechanisms by which N. brasiliensis modulates the immune system to survive in the host and advances in medical treatment of human actinomycetoma. Antibiotics and antimicrobials that are effective against severe actinomycetoma infections with an excellent therapeutic outcome and experimental studies of drugs that show promising bacterial inhibition in vivo and in vitro were presented. Here we demonstrate a systemic strong acquired immune response in humans and experimental mice at the same time of a local dominance of anti inflammatory cytokines environment. The pathogenic mechanisms of some actinomycetes include generation of an immunosuppressive micro environment to evade the protective immune response. This information will be helpful in understanding pathogenesis and to design new drugs for treatment of actinomycetoma. PMID:22825801

  2. Nocardia brasiliensis infection mimicking juvenile idiopathic arthritis in a 4-year-old girl.

    PubMed

    Kapur, Nitin; Adib, Navid; Grimwood, Keith

    2013-11-01

    Nocardia are ubiquitous environmental saprophytes that cause pneumonia and disseminated disease in immunocompromised patients. They can also cause localized cutaneous and soft tissue infections in healthy people after direct percutaneous inoculation. Nocardia arthritis is rare in both forms of the disease. Here we present the first published case of a child with septic arthritis caused by N brasiliensis. Importantly, this otherwise well 4-year-old girl had no known history of trauma but presented with transient cutaneous lesions and a 6-week history of arthritis involving the right fourth digit proximal interphalangeal joint without accompanying fever or raised systemic inflammatory markers. She received a diagnosis of juvenile idiopathic arthritis and underwent antiinflammatory and immunosuppressant therapy. After 2 months she developed frank septic arthritis, which necessitated a surgical joint washout, from which an intraoperative swab grew N brasiliensis. The patient received 6 months of high-dose trimethoprim-sulfamethoxazole and remains well more than 4 years after treatment. This unusual case highlights the importance of considering an indolent infection from slow-growing organisms, including Nocardia, when diagnosing the oligoarthritis subtype of juvenile idiopathic arthritis. This is especially relevant when a single joint is involved and response to antiinflammatory therapy is suboptimal because antiinflammatory agents may mask evolving signs of infection. PMID:24127474

  3. Sequence and expression analyses of ethylene response factors highly expressed in latex cells from Hevea brasiliensis.

    PubMed

    Piyatrakul, Piyanuch; Yang, Meng; Putranto, Riza-Arief; Pirrello, Julien; Dessailly, Florence; Hu, Songnian; Summo, Marilyne; Theeravatanasuk, Kannikar; Leclercq, Julie; Kuswanhadi; Montoro, Pascal

    2014-01-01

    The AP2/ERF superfamily encodes transcription factors that play a key role in plant development and responses to abiotic and biotic stress. In Hevea brasiliensis, ERF genes have been identified by RNA sequencing. This study set out to validate the number of HbERF genes, and identify ERF genes involved in the regulation of latex cell metabolism. A comprehensive Hevea transcriptome was improved using additional RNA reads from reproductive tissues. Newly assembled contigs were annotated in the Gene Ontology database and were assigned to 3 main categories. The AP2/ERF superfamily is the third most represented compared with other transcription factor families. A comparison with genomic scaffolds led to an estimation of 114 AP2/ERF genes and 1 soloist in Hevea brasiliensis. Based on a phylogenetic analysis, functions were predicted for 26 HbERF genes. A relative transcript abundance analysis was performed by real-time RT-PCR in various tissues. Transcripts of ERFs from group I and VIII were very abundant in all tissues while those of group VII were highly accumulated in latex cells. Seven of the thirty-five ERF expression marker genes were highly expressed in latex. Subcellular localization and transactivation analyses suggested that HbERF-VII candidate genes encoded functional transcription factors. PMID:24971876

  4. Chemokine and cytokine expression in murine intestinal epithelium following Nippostrongylus brasiliensis infection.

    PubMed

    Rosbottom, Anne; Knight, Pamela A; McLachlan, Gerry; Thornton, Elizabeth M; Wright, Steven W; Miller, Hugh R P; Scudamore, Cheryl L

    2002-02-01

    Infection of mice with the nematode parasite Nippostrongylus brasiliensis results in a well characterized intestinal mastocytosis with intraepithelial migration of mucosal mast cells (MMC). The molecules mediating this response are unknown. We examined expression of several putative mast cell chemoattractants in intestinal epithelium following N. brasiliensis infection. Expression of the chemokines monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1 alpha (MIP-1alpha), RANTES (regulated on activation normal T-cell expressed and secreted), fractalkine, and thymocyte expressed chemokine (TECK); and the cytokines stem cell factor (SCF) and transforming growth factor beta1 (TGFbeta1), was constitutive and no alteration was detected following infection. MCP-1 expression was also constitutive but at much lower levels and increased expression was detected on days 7 and 14 postinfection. Expression of MCP-1 in whole jejunum was at much higher levels than in epithelium. Constitutive expression of MCP-1, MIP-1alpha and TGFbeta1 was also detected in cultured bone marrow-derived homologues of MMC. In an intestinal epithelial cell line (CMT-93), there was constitutive expression of SCF, TGFalpha1, fractalkine and MCP-1. The results show that, in vivo, epithelium is a potentially important source of mast cell chemoattractants. PMID:11874561

  5. Molecular cloning, expression profiles and characterization of a glutathione reductase in Hevea brasiliensis.

    PubMed

    Deng, Zhi; Zhao, Manman; Liu, Hui; Wang, Yuekun; Li, Dejun

    2015-11-01

    Glutathione reductase (GR; EC 1.8.1.7) is an important oxidoreductase that can protect organisms against various oxidative stresses. In this study, a new GR gene, named as HbGR2, was isolated from Hevea brasiliensis. The HbGR2 cDNA contained a 1674-bp open reading frame encoding 557 amino acids and the deduced HbGR2 protein showed high identities to the chloroplastic GRs from other plant species. HbGR2 was localized in the chloroplasts of tobacco mesophyll protoplasts. The cis-acting regulatory elements related to stress or hormone responses were predicted in the promoter region of HbGR2. The results from real-time RT-PCR analyses showed that HbGR2 was expressed throughout different tissues and developmental stages of leaves. Besides being related to tapping panel dryness (TPD), HbGR2 was regulated by several treatments including ethephon (ET), methyl jasmonate (MeJA), drought, low temperature, high salt, wounding and hydrogen peroxide (H2O2). The Escherichia coli (E. coli) cells overexpressing HbGR2 markedly increased their tolerance and survival at high concentrations of H2O2, suggesting that HbGR2 might play an important role in oxidative stress response in Hevea brasiliensis. PMID:26232647

  6. Green synthesis of colloidal silver nanoparticles using natural rubber latex extracted from Hevea brasiliensis.

    PubMed

    Guidelli, Eder José; Ramos, Ana Paula; Zaniquelli, Maria Elisabete D; Baffa, Oswaldo

    2011-11-01

    Colloidal silver nanoparticles were synthesized by an easy green method using thermal treatment of aqueous solutions of silver nitrate and natural rubber latex (NRL) extracted from Hevea brasiliensis. The UV-Vis spectra detected the characteristic surface plasmonic absorption band around 435 nm. Both NRL and AgNO(3) contents in the reaction medium have influence in the Ag nanoparticles formation. Lower AgNO(3) concentration led to decreased particle size. The silver nanoparticles presented diameters ranging from 2 nm to 100 nm and had spherical shape. The selected area electron diffraction (SAED) patterns indicated that the silver nanoparticles have face centered cubic (fcc) crystalline structure. FTIR spectra suggest that reduction of the silver ions are facilitated by their interaction with the amine groups from ammonia, which is used for conservation of the NRL, whereas the stability of the particles results from cis-isoprene binding onto the surface of nanoparticles. Therefore natural rubber latex extracted from H. brasiliensis can be employed in the preparation of stable aqueous dispersions of silver nanoparticles acting as a dispersing and/or capping agent. Moreover, this work provides a new method for the synthesis of silver nanoparticles that is simple, easy to perform, pollutant free and inexpensive. PMID:21803643

  7. Sequence and Expression Analyses of Ethylene Response Factors Highly Expressed in Latex Cells from Hevea brasiliensis

    PubMed Central

    Piyatrakul, Piyanuch; Yang, Meng; Putranto, Riza-Arief; Pirrello, Julien; Dessailly, Florence; Hu, Songnian; Summo, Marilyne; Theeravatanasuk, Kannikar; Leclercq, Julie; Kuswanhadi; Montoro, Pascal

    2014-01-01

    The AP2/ERF superfamily encodes transcription factors that play a key role in plant development and responses to abiotic and biotic stress. In Hevea brasiliensis, ERF genes have been identified by RNA sequencing. This study set out to validate the number of HbERF genes, and identify ERF genes involved in the regulation of latex cell metabolism. A comprehensive Hevea transcriptome was improved using additional RNA reads from reproductive tissues. Newly assembled contigs were annotated in the Gene Ontology database and were assigned to 3 main categories. The AP2/ERF superfamily is the third most represented compared with other transcription factor families. A comparison with genomic scaffolds led to an estimation of 114 AP2/ERF genes and 1 soloist in Hevea brasiliensis. Based on a phylogenetic analysis, functions were predicted for 26 HbERF genes. A relative transcript abundance analysis was performed by real-time RT-PCR in various tissues. Transcripts of ERFs from group I and VIII were very abundant in all tissues while those of group VII were highly accumulated in latex cells. Seven of the thirty-five ERF expression marker genes were highly expressed in latex. Subcellular localization and transactivation analyses suggested that HbERF-VII candidate genes encoded functional transcription factors. PMID:24971876

  8. Chemically-Mediated Roostmate Recognition and Roost Selection by Brazilian Free-Tailed Bats (Tadarida brasiliensis)

    PubMed Central

    Englert, Amy C.; Greene, Michael J.

    2009-01-01

    Background The Brazilian free-tailed bat (Tadarida brasiliensis) is an exceptionally social and gregarious species of chiropteran known to roost in assemblages that can number in the millions. Chemical recognition of roostmates within these assemblages has not been extensively studied despite the fact that an ability to chemically recognize individuals could play an important role in forming and stabilizing complex suites of social interactions. Methodology/Principal Findings Individual bats were given a choice between three roosting pouches: one permeated with the scent of a group of roostmates, one permeated with the scent of non-roostmates, and a clean control. Subjects rejected non-roostmate pouches with greater frequency than roostmate pouches or blank control pouches. Also, bats chose to roost in the roostmate scented pouches more often than the non-roostmate or control pouches. Conclusions/Significance We demonstrated that T. brasiliensis has the ability to chemically recognize roostmates from non-roostmates and a preference for roosting in areas occupied by roostmates. It is important to investigate these behaviors because of their potential importance in colony dynamics and roost choice. PMID:19901986

  9. Coherent regulation in yeast’s cell-cycle network

    NASA Astrophysics Data System (ADS)

    Aral, Ne?e; Kabakç?o?lu, Alkan

    2015-05-01

    We define a measure of coherent activity for gene regulatory networks, a property that reflects the unity of purpose between the regulatory agents with a common target. We propose that such harmonious regulatory action is desirable under a demand for energy efficiency and may be selected for under evolutionary pressures. We consider two recent models of the cell-cycle regulatory network of the yeast, Saccharomyces cerevisiae as a case study and calculate their degree of coherence. A comparison with random networks of similar size and composition reveals that the yeast’s cell-cycle regulation is wired to yield an exceptionally high level of coherent regulatory activity. We also investigate the mean degree of coherence as a function of the network size, connectivity and the fraction of repressory/activatory interactions.

  10. Comparative study on the technological properties of latex and natural rubber from Hancornia speciosa Gomes and Hevea brasiliensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This work reports a systematic comparative study of the properties of natural lattices and rubbers extracted from Hancornia speciosa Gomes and Hevea brasiliensis [(Willd. ex Adr. de Juss.) Muell.-Arg.] (clone RRIM 600) trees from 11 collections in Brazil throughout 2004. Natural rubber latex particl...

  11. Enzyme-linked immunosorbent assay for serological diagnosis of Nocardia brasiliensis and clinical correlation with mycetoma infections.

    PubMed Central

    Salinas-Carmona, M C; Welsh, O; Casillas, S M

    1993-01-01

    We previously identified three immunodominant antigens obtained from a Nocardia brasiliensis cell extract and recognized by sera from mycetoma patients (M. C. Salinas-Carmona, L. Vera, O. Welsh, and M. Rodríguez, Zentralbl. Bakteriol. 276:390-397, 1992). In the present work, we obtained a crude extract from a mass culture of N. brasiliensis HUJEG-1 and purified two immunodominant antigens, the 26- and 24-kDa proteins, by using simple physiochemical techniques. With these antigens, we developed a conventional solid-phase enzyme-linked immunosorbent assay and tested 30 serum samples from mycetoma patients, 29 from tuberculosis patients, 24 from a leprosy group, and 31 from healthy individuals. Our results show for the first time statistically significant differences in serology among these groups. All mycetoma patients with a positive culture for N. brasiliensis had absorbance values higher than 0.3. On the other hand, the mycobacterium-infected patients as well as the healthy individuals all had absorbance values below that level. Moreover, we found a close correlation between the clinical condition of the mycetoma patients and the anti-26- and anti-24-kDa protein antibody concentrations. We therefore propose the use of this assay in routine clinical laboratories to confirm the diagnosis of N. brasiliensis infection in human mycetoma cases. In addition, the possible application of this assay in the serodiagnosis of Nocardia asteroides infection is also discussed. Images PMID:8263174

  12. Yeast Genetics and Biotechnological Applications

    NASA Astrophysics Data System (ADS)

    Mishra, Saroj; Baranwal, Richa

    Yeast can be recognized as one of the very important groups of microorganisms on account of its extensive use in the fermentation industry and as a basic eukaryotic model cellular system. The yeast Saccharomyces cerevisiae has been extensively used to elucidate the genetics and regulation of several key functions in the cell such as cell mating, electron transport chain, protein trafficking, cell cycle events and others. Even before the genome sequence of the yeast was out, the structural organization and function of several of its genes was known. With the availability of the origin of replication from the 2 ?m plasmid and the development of transformation system, it became the host of choice for expression of a number of important proteins. A large number of episomal and integrative shuttle vectors are available for expression of mammalian proteins. The latest developments in genomics and micro-array technology have allowed investigations of individual gene function by site-specific deletion method. The application of metabolic profiling has also assisted in understanding the cellular network operating in this yeast. This chapter is aimed at reviewing the use of this system as an experimental tool for conducting classical genetics. Various vector systems available, foreign genes expressed and the limitations as a host will be discussed. Finally, the use of various yeast enzymes in biotechnology sector will be reviewed.

  13. Progress in Yeast Glycosylation Engineering.

    PubMed

    Hamilton, Stephen R; Zha, Dongxing

    2015-01-01

    While yeast are lower eukaryotic organisms, they share many common features and biological processes with higher eukaryotes. As such, yeasts have been used as model organisms to facilitate our understanding of such features and processes. To this end, a large number of powerful genetic tools have been developed to investigate and manipulate these organisms. Going hand-in-hand with these genetic tools is the ability to efficiently scale up the fermentation of these organisms, thus making them attractive hosts for the production of recombinant proteins. A key feature of producing recombinant proteins in yeast is that these proteins can be readily secreted into the culture supernatant, simplifying any downstream processing. A consequence of this secretion is that the proteins typically pass through the secretory pathway, during which they may be exposed to various posttranslational modifications. The addition of glycans is one such modification. Unfortunately, while certain aspects of glycosylation are shared between lower and higher eukaryotes, significant differences exist. Over the last two decades much research has focused on engineering the glycosylation pathways of yeast to more closely resemble those of higher eukaryotes, particularly those of humans for the production of therapeutic proteins. In the current review we shall highlight some of the key achievements in yeast glyco-engineering which have led to humanization of both the N- and O-linked glycosylation pathways. PMID:26082216

  14. Domestic, peridomestic and wild hosts in the transmission of Trypanosoma cruzi in the Caatinga area colonised by Triatoma brasiliensis

    PubMed Central

    Bezerra, Claudia Mendonça; Cavalcanti, Luciano Pamplona de Góes; de Souza, Rita de Cássia Moreira; Barbosa, Silvia Ermelinda; Xavier, Samanta Cristina das Chagas; Jansen, Ana Maria; Ramalho, Relrison Dias; Diotaiut, Liléia

    2014-01-01

    The role played by different mammal species in the maintenance of Trypanosoma cruzi is not constant and varies in time and place. This study aimed to characterise the importance of domestic, wild and peridomestic hosts in the transmission of T. cruzi in Tauá, state of Ceará, Caatinga area, Brazil, with an emphasis on those environments colonised by Triatoma brasiliensis. Direct parasitological examinations were performed on insects and mammals, serologic tests were performed on household and outdoor mammals and multiplex polymerase chain reaction was used on wild mammals. Cytochrome b was used as a food source for wild insects. The serum prevalence in dogs was 38% (20/53), while in pigs it was 6% (2/34). The percentages of the most abundantly infected wild animals were as follows: Thrichomys laurentius 74% (83/112) and Kerodon rupestris 10% (11/112). Of the 749 triatomines collected in the household research, 49.3% (369/749) were positive for T. brasiliensis, while 6.8% were infected with T. cruzi (25/369). In captured animals, T. brasiliensis shares a natural environment with T. laurentius, K. rupestris, Didelphis albiventris, Monodelphis domestica, Galea spixii, Wiedomys pyrrhorhinos, Conepatus semistriatus and Mus musculus. In animals identified via their food source, T. brasiliensis shares a natural environment with G. spixii, K. rupestris, Capra hircus, Gallus gallus, Tropidurus oreadicus and Tupinambis merianae. The high prevalence of T. cruzi in household and peridomiciliar animals reinforces the narrow relationship between the enzootic cycle and humans in environments with T. brasiliensis and characterises it as ubiquitous. PMID:25410992

  15. Domestic, peridomestic and wild hosts in the transmission of Trypanosoma cruzi in the Caatinga area colonised by Triatoma brasiliensis.

    PubMed

    Bezerra, Claudia Mendonça; Cavalcanti, Luciano Pamplona de Góes; Souza, Rita de Cássia Moreira de; Barbosa, Silvia Ermelinda; Xavier, Samanta Cristina das Chagas; Jansen, Ana Maria; Ramalho, Relrison Dias; Diotaiut, Liléia

    2014-11-01

    The role played by different mammal species in the maintenance of Trypanosoma cruzi is not constant and varies in time and place. This study aimed to characterise the importance of domestic, wild and peridomestic hosts in the transmission of T. cruzi in Tauá, state of Ceará, Caatinga area, Brazil, with an emphasis on those environments colonised by Triatoma brasiliensis. Direct parasitological examinations were performed on insects and mammals, serologic tests were performed on household and outdoor mammals and multiplex polymerase chain reaction was used on wild mammals. Cytochrome b was used as a food source for wild insects. The serum prevalence in dogs was 38% (20/53), while in pigs it was 6% (2/34). The percentages of the most abundantly infected wild animals were as follows: Thrichomys laurentius 74% (83/112) and Kerodon rupestris 10% (11/112). Of the 749 triatomines collected in the household research, 49.3% (369/749) were positive for T. brasiliensis, while 6.8% were infected with T. cruzi (25/369). In captured animals, T. brasiliensis shares a natural environment with T. laurentius, K. rupestris, Didelphis albiventris, Monodelphis domestica, Galea spixii, Wiedomys pyrrhorhinos, Conepatus semistriatus and Mus musculus. In animals identified via their food source, T. brasiliensis shares a natural environment with G. spixii, K. rupestris, Capra hircus, Gallus gallus, Tropidurus oreadicus and Tupinambis merianae. The high prevalence of T. cruzi in household and peridomiciliar animals reinforces the narrow relationship between the enzootic cycle and humans in environments with T. brasiliensis and characterises it as ubiquitous. PMID:25410992

  16. Toxicogenomics using yeast DNA microarrays.

    PubMed

    Yasokawa, Daisuke; Iwahashi, Hitoshi

    2010-11-01

    Development of genomics and bioinformatics enable us to analyze the global gene expression profiles of cells by DNA microarray. Changes in gene expression patterns indicate changes in its physiological conditions. Following the exposure of an organism or cell to toxic chemicals or other environmental stresses, the global genetic responses can be expeditiously and easily analyzed. Baker's yeast, Saccharomyces cerevisiae, is one of the most studied and useful model eukaryotes. The biggest advantage of yeast genomics is the available functional information for each gene and a considerable number of data are accumulating in the field of toxicity assessment using yeast DNA microarray. In this review, we discuss the toxicogenomics of metal ions, alcohols and aldehydes, and other chemicals. PMID:20624688

  17. [Alkalitolerant yeasts from natural biotopes].

    PubMed

    Lisichkina, G A; Bab'eva, I P; Sorokin, D Iu

    2003-01-01

    Using a solid nutrient medium containing alkaline buffer (pH 10) and an antibiotic, alkalitolerant yeasts were isolated from samples of soda-rich saline soils (solonchaks) of Armenia (Arazdayan) and the Transbaikal Region (the Kungur Steppe). The species diversity of the yeast populations of the tested soda-rich soils was relatively insignificant. They only contained alkalitolerant representatives of asporogenic capsulated yeasts belonging to the species Cryptococcus laurentii, C. albidus, Rhodotorula glutinis, R. mucilaginosa, and Sporobolomyces roseus. C. laurentii representatives clearly dominated the isolates obtained, their number exceeding that of the other species by 2-3 orders of magnitude. All of the isolates grew on acidic wort agar, suggesting that they did not include obligate alkaliphiles. PMID:14679910

  18. PHYLOGENETICS OF SACCHAROMYCETALES, THE ASCOMYCETE YEASTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ascomycete yeasts (Phylum Ascomycota: Subphylum Saccharomycotina: Class Saccharomycetes: Order Saccharomycetales) comprise a monophyletic lineage with a single order of about 1000 known species. These yeasts live as saprobes, often in association with plants, animals, and their interfaces. A few s...

  19. Yeast Can Affect Behavior and Learning.

    ERIC Educational Resources Information Center

    Crook, William G.

    1984-01-01

    A pediatrician recounts his experiences in diagnosing and treating allergies to common yeast germs that may result in behavior and learning problems. He lists characteristics that may predispose children to yeast-connected health problems. (CL)

  20. Chromatin and Transcription in Yeast

    PubMed Central

    Rando, Oliver J.; Winston, Fred

    2012-01-01

    Understanding the mechanisms by which chromatin structure controls eukaryotic transcription has been an intense area of investigation for the past 25 years. Many of the key discoveries that created the foundation for this field came from studies of Saccharomyces cerevisiae, including the discovery of the role of chromatin in transcriptional silencing, as well as the discovery of chromatin-remodeling factors and histone modification activities. Since that time, studies in yeast have continued to contribute in leading ways. This review article summarizes the large body of yeast studies in this field. PMID:22345607

  1. Mitochondrial inheritance in budding yeast.

    PubMed

    Boldogh, I R; Yang, H C; Pon, L A

    2001-06-01

    During the past decade significant advances were made toward understanding the mechanism of mitochondrial inheritance in the yeast Saccharomyces cerevisiae. A combination of genetics, cell-free assays and microscopy has led to the discovery of a great number of components. These fall into three major categories: cytoskeletal elements, mitochondrial membrane components and regulatory proteins. These proteins mediate activities, including movement of mitochondria from mother cells to buds, segregation of mitochondria and mitochondrial DNA, and equal distribution of the organelle between mother cells and buds during yeast cell division. PMID:11389764

  2. Lacazia loboi gen. nov., comb. nov., the Etiologic Agent of Lobomycosis

    PubMed Central

    Taborda, Paulo R.; Taborda, Valeria A.; McGinnis, Michael R.

    1999-01-01

    The new genus Lacazia P. Taborda, V. Taborda, et McGinnis is proposed to accommodate Lacazia loboi (O. M. Fonseca et Lacaz) P. Taborda, V. Taborda, et McGinnis, the obligate pathogen that causes lobomycosis in mammals. The continued placement of that fungus in the genus Paracoccidioides Almeida as Paracoccidioides loboi is taxonomically inappropriate. Loboa loboi Ciferri et al. is a synonym of Paracoccidioides brasiliensis. PMID:10325371

  3. 21 CFR 73.355 - Phaffia yeast.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Phaffia yeast. 73.355 Section 73.355 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.355 Phaffia yeast. (a) Identity. (1) The color additive phaffia yeast consists of the killed, dried...

  4. Yeast: A Research Organism for Teaching Genetics.

    ERIC Educational Resources Information Center

    Manney, Thomas R.; Manney, Monta L.

    1992-01-01

    Explains why laboratory strains of bakers yeast, Saccharomyces cerevisiae, are particularly suited for classroom science activities. Describes the sexual life cycle of yeast and the genetic system with visible mutations. Presents an overview of activities that can be done with yeast and gives a source for teachers to obtain more information. (PR)

  5. Cultivated strains of Agaricus bisporus and A. brasiliensis: chemical characterization and evaluation of antioxidant and antimicrobial properties for the final healthy product--natural preservatives in yoghurt.

    PubMed

    Stojkovi?, Dejan; Reis, Filipa S; Glamo?lija, Jasmina; ?iri?, Ana; Barros, Lillian; Van Griensven, Leo J L D; Ferreira, Isabel C F R; Sokovi?, Marina

    2014-07-25

    Agaricus bisporus (J. E. Lange) Emil J. Imbach and Agaricus brasiliensis Wasser, M. Didukh, Amazonas & Stamets are edible mushrooms. We chemically characterized these mushrooms for nutritional value, hydrophilic and lipophilic compounds. The antioxidant and antimicrobial activities of methanolic and ethanolic extracts were assessed. Hepatotoxicity was also evaluated. The ethanolic extract of both species was tested for inhibition of Listeria monocytogenes growth in yoghurt. Both species proved to be a good source of bioactive compounds. A. brasiliensis was richer in polyunsaturated fatty acids and revealed the highest concentration of phenolic acids, and tocopherols. A. bisporus showed the highest monounsaturated fatty acids and ergosterol contents. A. brasiliensis revealed the highest antioxidant potential, and its ethanolic extract displayed the highest antibacterial potential; the methanolic extract of A. bisporus revealed the highest antifungal activity. A. brasiliensis possessed better preserving properties in yoghurt. PMID:24881564

  6. Yeast Proteomics and Protein Microarrays

    PubMed Central

    Chen, Rui; Snyder, Michael

    2010-01-01

    Our understanding of biological processes as well as human diseases has improved greatly thanks to studies on model organisms such as yeast. The power of scientific approaches with yeast lies in its relatively simple genome, its facile classical and molecular genetics, as well as the evolutionary conservation of many basic biological mechanisms. However, even in this simple model organism, systems biology studies, especially proteomic studies had been an intimidating task. During the past decade, powerful high-throughput technologies in proteomic research have been developed for yeast including protein microarray technology. The protein microarray technology allows the interrogation of protein-protein, protein-DNA, protein-small molecule interaction networks as well as post-translational modification networks in a large-scale, high-throughput manner. With this technology, many groundbreaking findings have been established in studies with the budding yeast Saccharomyces cerevisiae, most of which could have been unachievable with traditional approaches. Discovery of these networks has profound impact on explicating biological processes with a proteomic point of view, which may lead to a better understanding of normal biological phenomena as well as various human diseases. PMID:20728591

  7. Yeast as factory and factotum.

    PubMed

    Dixon, B

    2000-02-01

    After centuries of vigorous activity in making fine wines, beers and breads, Saccharomyces cerevisiae is now acquiring a rich new portfolio of skills, bestowed by genetic manipulation. As shown in a recent shop-window of research supported by the European Commission, yeasts will soon be benefiting industries as diverse as fish farming, pharmaceuticals and laundering. PMID:11190211

  8. Emergence of co-trimoxazole resistant Nocardia brasiliensis causing fatal pneumonia.

    PubMed

    Khare, Vineeta; Gupta, Prashant; Himanshu, D; Kumar, Deepak

    2013-01-01

    An 85-year-old man was admitted to the medical intensive care unit with a 10-day history of severe breathlessness, fever and cough. The patient was known to have chronic obstructive pulmonary disease and had been receiving corticosteroids in the preceding 18 months. He had been treated for tuberculosis 2.5 years previously. On examination he was febrile, tachycardic with a respiratory rate of 46/min. Auscultation revealed bilateral crepitation's and wheeze. Chest radiograph revealed patchy infiltrates on right lung. The patient developed respiratory depression and was mechanically ventilated. His sputum and endotracheal aspirates revealed Nocardia brasiliensis on culture which was found to be co-trimoxazole resistant. Once this became known imipenem was substituted for co-trimoxazole but unfortunately condition of the patient did not improve and he died following a cardiac arrest. PMID:23598938

  9. Primary cutaneous Nocardia brasiliensis infection isolated in an immunosuppressed patient: a case report.

    PubMed

    Lai, Kimberly W; Brodell, Lindsey A; Lambert, Emily; Menegus, Marilyn; Scott, Glynis A; Tu, John H

    2012-02-01

    Cutaneous nocardiosis is a rare infection that may manifest as a superficial skin lesion, lymphocutaneous infection, mycetoma, or diffuse cutaneous infection from a disseminated systemic infection. We report a case of a 65-year-old immunocompromised man with persistent primary cutaneous Nocardia brasiliensis infection following a motor vehicle collision. A high degree of suspicion is needed to diagnose Nocardia infection because of its resemblance to other bacterial infections. Nocardiosis should be included in the differential diagnosis of chronic cutaneous infections, especially when the response to antibiotics is inadequate or when the patient is immunocompromised. Because Nocardia may take several weeks to grow in standard bacterial culture media, laboratories should be notified of the suspicion so that culture plates are held for longer time periods. Long-term therapy, usually with sulfonamides, often is necessary. PMID:22474729

  10. A case of an immunocompetent young man obtaining community-acquired disseminated Nocardia brasiliensis.

    PubMed

    Li, Jinna; Cao, Jie; Wu, Yueqing; Wan, Nansheng; Pan, Li; Chen, Yuanbao

    2014-01-01

    Nocardiosis is a rare but severe pyogenic or granulomatous disease and caused by Nocardia that mainly infects immunocompromised patients. We report here a case of an immunocompetent 24-year-old male student with community-acquired pneumonia with asymptomatic disseminated cerebral abscess by Brasiliensis nocardiosis. The patient was fully recovered after receiving optimized antimicrobial therapy without relapse. This case suggests the health professionals such as the physicians of pulmonary, infection, neurology department and et al should always think about unusual cause of community acquired pneumonia, even in immunocompetent patients and when having pulmonary nocardiosis we should do a radiological neurological work up, even with the absence of neurological finding or symptom. PMID:24594251

  11. Tourism values for Mexican free-tailed bat (Tadarida brasiliensis mexicana) viewing

    USGS Publications Warehouse

    Bagstad, Kenneth J.; Widerholdt, Ruscena

    2013-01-01

    Migratory species provide diverse ecosystem services to people, but these values have seldom been estimated rangewide for a single species. In this article, we summarize visitation and consumer surplus for recreational visitors to viewing sites for the Mexican free-tailed bat (Tadarida brasiliensis mexicana) throughout the Southwestern United States. Public bat viewing opportunities are available at 17 of 25 major roosts across six states; on an annual basis, we estimate that over 242,000 visitors view bats, gaining over $6.5 million in consumer surplus. A better understanding of spatial mismatches between the areas where bats provide value to people and areas most critical for maintaining migratory populations can better inform conservation planning, including economic incentive systems for conservation.

  12. Mercury levels in tissues of Giant otters (Pteronura brasiliensis) from the Rio Negro, Pantanal, Brazil.

    TOXLINE Toxicology Bibliographic Information

    Dias Fonseca FR; Malm O; Francine Waldemarin H

    2005-07-01

    This research reports the first data on mercury levels found in Giant otters (Pteronura brasiliensis) from South America. Mercury concentrations were analyzed from different organs/tissues of two animals found dead floating on the water of the Rio Negro in the Pantanal, Brazil. The mean mercury concentration ranged from 2.94 to 3.68 microg/g in hair, from 1.52 to 4.3 microg/g in liver, and from 1.11 to 4.59 microg/g in kidney and was 0.17 microg/g in muscle samples. In comparison with other research, there is no evidence of contamination in these animals and mercury concentrations in tissues appeared to be at levels below those associated with toxicity.

  13. Mercury levels in tissues of Giant otters (Pteronura brasiliensis) from the Rio Negro, Pantanal, Brazil.

    PubMed

    Dias Fonseca, Fabrizio Rafael; Malm, Olaf; Francine Waldemarin, Helen

    2005-07-01

    This research reports the first data on mercury levels found in Giant otters (Pteronura brasiliensis) from South America. Mercury concentrations were analyzed from different organs/tissues of two animals found dead floating on the water of the Rio Negro in the Pantanal, Brazil. The mean mercury concentration ranged from 2.94 to 3.68 microg/g in hair, from 1.52 to 4.3 microg/g in liver, and from 1.11 to 4.59 microg/g in kidney and was 0.17 microg/g in muscle samples. In comparison with other research, there is no evidence of contamination in these animals and mercury concentrations in tissues appeared to be at levels below those associated with toxicity. PMID:15910792

  14. Protective Effect of Agaricus brasiliensis on STZ-Induced Diabetic Neuropathic Pain in Rats.

    PubMed

    Ji, Weifeng; Huang, Haiying; Chao, Ji; Lu, Wuchao; Guo, Jianyou

    2014-01-01

    Objective. The present investigation examined the neuroprotective effect of Agaricus brasiliensis (AbS) against STZ-induced diabetic neuropathic pain in laboratory rats. STZ-induced diabetic rats were administered orally with AbS. Body weight, serum glucose, and behavioral parameters were measured before and at the end of the experiment to see the effect of AbS on these parameters. After 6 weeks of treatments, all animals were sacrificed to study various biochemical parameters. Treatment with AbS 80?mg/kg in diabetic animals showed significant increase in body weight, pain threshold, and paw withdrawal threshold and significant decrease in serum glucose, LPO and NO level, Na-K-ATPase level, and TNF- ? and IL-1 ? level as compared to vehicle treated diabetic animals in dose and time dependent manner. AbS can offer pain relief in PDN. This may be of potential benefit in clinical practice for the management of diabetic neuropathy. PMID:24527050

  15. Anthocyanins from Eugenia brasiliensis edible fruits as potential therapeutics for COPD treatment

    PubMed Central

    Flores, Gema; Dastmalchi, Keyvan; Paulino, Sturlainny; Whalen, Kathleen; Dabo, Abdoulaye J.; Reynertson, Kurt A.; Foronjy, Robert F.; D Armiento, Jeanine M.; Kennelly, Edward J.

    2012-01-01

    Nine anthocyanins (1–9) from the edible fruits of Eugenia brasiliensis were identified by HPLC-PDA and LC-MS, and seven of these are described for the first time in this Brazilian fruit. Two of the major anthocyanins, delphinidin (8) and cyanidin (9), were studied for their inhibitory activity against chemokine interleukin-8 (IL-8) production before and after cigarette smoke extract (CSE) treatment of cells. In non-treated cells the amount of IL-8 was unchanged following treatment with cyanidin and delphinidin in concentrations 0.1–10 M. Both delphinidin (8) and cyanidin (9) decreased the production of IL-8 in treated cells, at 1 M and 10 M, respectively. Delphinidin (8) demonstrated IL-8 inhibition in the CSE treated cells in a dose-dependent manner. PMID:25005941

  16. [Evaluation of chemical and nutritional characteristics of the seed of the rubber tree (Hevea brasiliensis)].

    PubMed

    Selle, C M; González de Mejía, E; Elías, L G; Bressani, R

    1983-12-01

    Some chemical and nutritional characteristics of the rubber seed Hevea brasiliensis were studied. The protein content, its amino acid composition as well as the iron, calcium, phosphorus and cyanide (free and bound) concentrations, were determined in the dehulled seed. The effect of soaking, cooking, soaking-cooking and cooking-fat extraction procedure of the seed on the cyanide content and its in vivo protein utilization, was also evaluated. The protein quality was biologically assessed using the protein efficiency ratio (PER). The protein content of the seed was 18%, and the most limiting amino acid was threonine, with a chemical score of 71.6. The iron, calcium and phosphorus contents were 6.2, 109 and 429 mg/100 g, respectively. Its fat content was 48% with a total energy value of 702 kcal/100 g (2,948 Kj/100 g). The total cyanide content in the fresh seed was 130-230 mg/100 g; 6% was in the free form and 94% as bound cyanide. The most effective treatment for reducing the cyanide content was found to be 20 hours of soaking in water, combined with one hour of cooking. The raw seed had a low nutritive value and produced weight loss and death when fed to rats. The protein value, however, improved upon the seed treatment, reaching PER values close to those found in traditional cereals such as corn. It is therefore concluded that the seed of Hevea brasiliensis is a good source of energy, calcium, valine, isoleucine, phenylalanine and tyrosine. In contrast, it is a poor source of threonine, leucine and lysine. Its cyanide content is high, but when removed by treatment, such as soaking in water, cooking or fat extraction, the protein utilization can be improved. PMID:6679249

  17. Selenoprotein Expression in Macrophages Is Critical for Optimal Clearance of Parasitic Helminth Nippostrongylus brasiliensis.

    PubMed

    Nelson, Shakira M; Shay, Ashley E; James, Jamaal L; Carlson, Bradley A; Urban, Joseph F; Prabhu, K Sandeep

    2016-02-01

    The plasticity of macrophages is evident in helminthic parasite infections, providing protection from inflammation. Previously we demonstrated that the micronutrient selenium induces a phenotypic switch in macrophage activation from a classically activated (pro-inflammatory; M1/CAM) toward an alternatively activated (anti-inflammatory; M2/AAM) phenotype, where cyclooxygenase (COX)-dependent cyclopentenone prostaglandin J2 (15d-PGJ2) plays a key role. Here, we hypothesize that dietary selenium modulates macrophage polarization toward an AAM phenotype to assist in the increasing clearance of adult Nippostrongylus brasiliensis, a gastrointestinal nematode parasite. Mice on a selenium-adequate (0.08 ppm) diet significantly augmented intestinal AAM presence while decreasing adult worms and fecal egg production when compared with infection of mice on selenium-deficient (<0.01 ppm) diet. Further increase in dietary selenium to supraphysiological levels (0.4 ppm) had very little or no impact on worm expulsion. Normal adult worm clearance and enhanced AAM marker expression were observed in the selenium-supplemented Trsp(fl/fl)Cre(WT) mice that express selenoproteins driven by tRNA(Sec) (Trsp), whereas N. brasiliensis-infected Trsp(fl/fl)Cre(LysM) selenium-supplemented mice showed a decreased clearance, with lowered intestinal expression of several AAM markers. Inhibition of the COX pathway with indomethacin resulted in delayed worm expulsion in selenium-adequate mice. This was rescued with 15d-PGJ2, which partially recapitulated the effect of selenium supplementation on fecal egg output in addition to increasing markers of AAMs in the small intestine. Antagonism of PPARγ blocked the effect of selenium. These results suggest that optimal expression of selenoproteins and selenium-dependent production of COX-derived endogenous prostanoids, such as Δ(12)-PGJ2 and 15d-PGJ2, may regulate AAM activation to enhance anti-helminthic parasite responses. PMID:26644468

  18. Sucrose importation into laticifers of Hevea brasiliensis, in relation to ethylene stimulation of latex production

    PubMed Central

    Dusotoit-Coucaud, Anaïs; Brunel, Nicole; Kongsawadworakul, Panida; Viboonjun, Unchera; Lacointe, André; Julien, Jean-Louis; Chrestin, Hervé; Sakr, Soulaïman

    2009-01-01

    Background and Aims The major economic product of Hevea brasiliensis is a rubber-containing cytoplasm (latex), which flows out of laticifers (latex cells) when the bark is tapped. The latex yield is stimulated by ethylene. Sucrose, the unique precursor of rubber synthesis, must cross the plasma membrane through specific sucrose transporters before being metabolized in the laticifers. The relative importance of sucrose transporters in determining latex yield is unknown. Here, the effects of ethylene (by application of Ethrel®) on sucrose transporter gene expression in the inner bark tissues and latex cells of H. brasiliensis are described. Methods Experiments, including cloning sucrose transporters, real time RT-PCR and in situ hybridization, were carried out on virgin (untapped) trees, treated or untreated with the latex yield stimulant Ethrel. Key Results Seven putative full-length cDNAs of sucrose transporters were cloned from a latex-specific cDNA library. These transporters belong to all SUT (sucrose transporter) groups and differ by their basal gene expression in latex and inner soft bark, with a predominance of HbSUT1A and HbSUT1B. Of these sucrose transporters, only HbSUT1A and HbSUT2A were distinctly increased by ethylene. Moreover, this increase was shown to be specific to laticifers and to ethylene application. Conclusion The data and all previous information on sucrose transport show that HbSUT1A and HbSUT2A are related to the increase in sucrose import into laticifers, required for the stimulation of latex yield by ethylene in virgin trees. PMID:19567416

  19. Construction and analysis of the cDNA subtraction library of yeast and mycelial phases of Sporothrix globosa isolated in China: identification of differentially expressed genes*

    PubMed Central

    Hu, Qing-bi; He, Yu; Zhou, Xun

    2015-01-01

    Species included in the Sporothrix schenckii complex are temperature-dependent with dimorphic growth and cause sporotrichosis that is characterized by chronic and fatal lymphocutaneous lesions. The putative species included in the Sporothrix complex are S. brasiliensis, S. globosa, S. mexicana, S. pallida, S. schenckii, and S. lurei. S. globosa is the causal agent of sporotrichosis in China, and its pathogenicity appears to be closely related to the dimorphic transition, i.e. from the mycelial to the yeast phase, it adapts to changing environmental conditions. To determine the molecular mechanisms of the switching process that mediates the dimorphic transition of S. globosa, suppression subtractive hybridization (SSH) was used to prepare a complementary DNA (cDNA) subtraction library from the yeast and mycelial phases. Bioinformatics analysis was performed to profile the relationship between differently expressed genes and the dimorphic transition. Two genes that were expressed at higher levels by the yeast form were selected, and their differential expression levels were verified using a quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR). It is believed that these differently expressed genes are involved in the pathogenesis of S. globosa infection in China. PMID:26642182

  20. Construction and analysis of the cDNA subtraction library of yeast and mycelial phases of Sporothrix globosa isolated in China: identification of differentially expressed genes.

    PubMed

    Hu, Qing-Bi; He, Yu; Zhou, Xun

    2015-12-01

    Species included in the Sporothrix schenckii complex are temperature-dependent with dimorphic growth and cause sporotrichosis that is characterized by chronic and fatal lymphocutaneous lesions. The putative species included in the Sporothrix complex are S. brasiliensis, S. globosa, S. mexicana, S. pallida, S. schenckii, and S. lurei. S. globosa is the causal agent of sporotrichosis in China, and its pathogenicity appears to be closely related to the dimorphic transition, i.e. from the mycelial to the yeast phase, it adapts to changing environmental conditions. To determine the molecular mechanisms of the switching process that mediates the dimorphic transition of S. globosa, suppression subtractive hybridization (SSH) was used to prepare a complementary DNA (cDNA) subtraction library from the yeast and mycelial phases. Bioinformatics analysis was performed to profile the relationship between differently expressed genes and the dimorphic transition. Two genes that were expressed at higher levels by the yeast form were selected, and their differential expression levels were verified using a quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR). It is believed that these differently expressed genes are involved in the pathogenesis of S. globosa infection in China. PMID:26642182

  1. Distributional potential of the Triatoma brasiliensis species complex at present and under scenarios of future climate conditions

    PubMed Central

    2014-01-01

    Background The Triatoma brasiliensis complex is a monophyletic group, comprising three species, one of which includes two subspecific taxa, distributed across 12 Brazilian states, in the caatinga and cerrado biomes. Members of the complex are diverse in terms of epidemiological importance, morphology, biology, ecology, and genetics. Triatoma b. brasiliensis is the most disease-relevant member of the complex in terms of epidemiology, extensive distribution, broad feeding preferences, broad ecological distribution, and high rates of infection with Trypanosoma cruzi; consequently, it is considered the principal vector of Chagas disease in northeastern Brazil. Methods We used ecological niche models to estimate potential distributions of all members of the complex, and evaluated the potential for suitable adjacent areas to be colonized; we also present first evaluations of potential for climate change-mediated distributional shifts. Models were developed using the GARP and Maxent algorithms. Results Models for three members of the complex (T. b. brasiliensis, N?=?332; T. b. macromelasoma, N?=?35; and T. juazeirensis, N?=?78) had significant distributional predictivity; however, models for T. sherlocki and T. melanica, both with very small sample sizes (N?=?7), did not yield predictions that performed better than random. Model projections onto future-climate scenarios indicated little broad-scale potential for change in the potential distribution of the complex through 2050. Conclusions This study suggests that T. b. brasiliensis is the member of the complex with the greatest distributional potential to colonize new areas: overall; however, the distribution of the complex appears relatively stable. These analyses offer key information to guide proactive monitoring and remediation activities to reduce risk of Chagas disease transmission. PMID:24886587

  2. De novo transcriptome analysis of Hevea brasiliensis tissues by RNA-seq and screening for molecular markers

    PubMed Central

    2014-01-01

    Background The rubber tree, Hevea brasiliensis, is a species native to the Brazilian Amazon region and it supplies almost all the world’s natural rubber, a strategic raw material for a variety of products. One of the major challenges for developing rubber tree plantations is adapting the plant to biotic and abiotic stress. Transcriptome analysis is one of the main approaches for identifying the complete set of active genes in a cell or tissue for a specific developmental stage or physiological condition. Results Here, we report on the sequencing, assembling, annotation and screening for molecular markers from a pool of H. brasiliensis tissues. A total of 17,166 contigs were successfully annotated. Then, 2,191 Single Nucleotide Variation (SNV) and 1.397 Simple Sequence Repeat (SSR) loci were discriminated from the sequences. From 306 putative, mainly non-synonymous SNVs located in CDS sequences, 191 were checked for their ability to characterize 23 Hevea genotypes by an allele-specific amplification technology. For 172 (90%), the nucleotide variation at the predicted genomic location was confirmed, thus validating the different steps from sequencing to the in silico detection of the SNVs. Conclusions This is the first study of the H. brasiliensis transcriptome, covering a wide range of tissues and organs, leading to the production of the first developed SNP markers. This process could be amplified to a larger set of in silico detected SNVs in expressed genes in order to increase the marker density in available and future genetic maps. The results obtained in this study will contribute to the H. brasiliensis genetic breeding program focused on improving of disease resistance and latex yield. PMID:24670056

  3. Lesions associated with Halocercus brasiliensis Lins de Almeida, 1933 in the lungs of dolphins stranded in the Northeast of Brazil.

    PubMed

    Guimarães, J P; Febronio, A M B; Vergara-Parente, J E; Werneck, M R

    2015-04-01

    The parasitic fauna of cetaceans is an important tool for ecological studies, including analyses on the causes of death. Halocercus brasiliensis is a nematode frequently found in the bronchi and bronchioles of some cetaceans, and it is commonly associated with focal inflammation of the respiratory tract leading to bacterial pneumonia and septicemia and, sometimes, to death. The objective of this study was to report infections by H. brasiliensis in the respiratory tract of Delphinidae stranded on the northern seaside of Bahia, Sergipe, and south of Alagoas, all states in the northeast region of Brazil. A total of 30 individuals, 1 Feresa attenuate (pygmy killer whale), 9 Stenella clymene (Clymene dolphin), and 20 Sotalia guianensis (Guiana dolphin) were studied. In 16 of them, the presence of H. brasiliensis was observed with a mean intensity of 3.5 ± 0.6 (range 1-9) in the hosts. Macroscopically, parasitic calcified nodules, lung congestion, edema, and emphysema were observed. Histopathological examination showed interstitial and granulomatous pneumonia with multifocal infiltrates, discrete to moderate edema, congestion, diffuse hemorrhage, and foci of calcification. We conclude that parasitic pneumonia in the sampled individuals may have directly contributed to stranding and death of the animals. PMID:25171594

  4. Relative distribution of gastrin-, CCK-8-, NPY- and CGRP-immunoreactive cells in the digestive tract of dorado (Salminus brasiliensis).

    PubMed

    Pereira, R T; Costa, L S; Oliveira, I R C; Araújo, J C; Aerts, M; Vigliano, F A; Rosa, P V

    2015-04-01

    The endocrine cells (ECs) of the gastrointestinal mucosa form the largest endocrine system in the body, not only in terms of cell numbers but also in terms of the different produced substances. Data describing the association between the relative distributions of the peptide-specific ECs in relation to feeding habits can be useful tools that enable the creation of a general expected pattern of EC distribution. We aimed to investigate the distribution of ECs immunoreactive for the peptides gastrin (GAS), cholecystokinin (CCK-8), neuropeptide Y (NPY), and calcitonin gene-related peptide (CGRP) in different segments of the digestive tract of carnivorous fish dorado (Salminus brasiliensis) by using immunohistochemistry procedures. The distribution of endocrine cells immunoreactive for gastrin (GAS), cholecystokinin (CCK-8), neuropeptide Y (NPY), and calcitonin gene-related peptide (CGRP) in digestive tract of dorado S. brasiliensis was examined by immunohistochemistry. The results describe the association between the distribution of the peptide-specific endocrine cells and feeding habits in different carnivorous fish. The largest number of endocrine cells immunoreactive for GAS, CCK-8, and CGRP were found in the pyloric stomach region and the pyloric caeca. However, NPY-immunoreactive endocrine cells were markedly restricted to the midgut. The distribution pattern of endocrine cells identified in S. brasiliensis is similar to that found in other carnivorous fishes. PMID:25771084

  5. The birth of yeast peroxisomes.

    PubMed

    Yuan, Wei; Veenhuis, Marten; van der Klei, Ida J

    2016-05-01

    This contribution describes the phenotypic differences of yeast peroxisome-deficient mutants (pex mutants). In some cases different phenotypes were reported for yeast mutants deleted in the same PEX gene. These differences are most likely related to the marker proteins and methods used to detect peroxisomal remnants. This is especially evident for pex3 and pex19 mutants, where the localization of receptor docking proteins (Pex13, Pex14) resulted in the identification of peroxisomal membrane remnants, which do not contain other peroxisomal membrane proteins, such as the ring proteins Pex2, Pex10 and Pex12. These structures in pex3 and pex19 cells are the template for peroxisome formation upon introduction of the missing gene. Taken together, these data suggest that in all yeast pex mutants analyzed so far peroxisomes are not formed de novo but use membrane remnant structures as a template for peroxisome formation upon reintroduction of the missing gene. The relevance of this model for peroxisomal membrane protein and lipid sorting to peroxisomes is discussed. This article is part of a Special Issue entitled: Peroxisomes edited by Ralf Erdmann. PMID:26367802

  6. Nuclear Import of Yeast Proteasomes

    PubMed Central

    Burcoglu, Julianne; Zhao, Liang; Enenkel, Cordula

    2015-01-01

    Proteasomes are highly conserved protease complexes responsible for the degradation of aberrant and short-lived proteins. In highly proliferating yeast and mammalian cells, proteasomes are predominantly nuclear. During quiescence and cell cycle arrest, proteasomes accumulate in granules in close proximity to the nuclear envelope/ER. With prolonged quiescence in yeast, these proteasome granules pinch off as membraneless organelles, and migrate as stable entities through the cytoplasm. Upon exit from quiescence, the proteasome granules clear and the proteasomes are rapidly transported into the nucleus, a process reflecting the dynamic nature of these multisubunit complexes. Due to the scarcity of studies on the nuclear transport of mammalian proteasomes, we summarised the current knowledge on the nuclear import of yeast proteasomes. This pathway uses canonical nuclear localisation signals within proteasomal subunits and Srp1/Kap95, and the canonical import receptor, named importin/karyopherin αβ. Blm10, a conserved 240 kDa protein, which is structurally related to Kap95, provides an alternative import pathway. Two models exist upon which either inactive precursor complexes or active holo-enzymes serve as the import cargo. Here, we reconcile both models and suggest that the import of inactive precursor complexes predominates in dividing cells, while the import of mature enzymes mainly occurs upon exit from quiescence. PMID:26262643

  7. Occultifur tropicalis f.a., sp. nov., a novel cystobasidiomycetous yeast species isolated from tropical regions.

    PubMed

    Khunnamwong, Pannida; Surussawadee, Janjira; Jindamorakot, Sasitorn; Ribeiro, José R A; Hagler, Allen N; Limtong, Savitree

    2015-05-01

    Five strains representing a single novel anamorphic yeast species were isolated from sugar cane. Two strains were from tissue (DMKU-SE38, DMKU-SE59(T)) and two from the external surface (DMKU-SP385, DMKU-SP403) of leaves collected in Thailand and the fifth (IMUFRJ 52020) from the rhizoplane of sugar cane in an organically cultivated field in Brazil. On the basis of sequence analysis of the D1/D2 region of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) region, they were classified as representing a single species of the genus Occultifur. The sequences of the D1/D2 region of the LSU rRNA genes and the ITS regions of the five strains were either identical or differed from each other by only one nucleotide substitution. The novel species was related most closely to Occultifur brasiliensis f.a. CBS 12687(T) but with 0.7-1.0% nucleotide substitutions (4-6 nt) in the D1/D2 region of the LSU rRNA gene and 2.5-2.7% nucleotide substitutions (14-15 nt) in the ITS region. The name Occultifur tropicalis f.a., sp. nov. is proposed. The type strain is DMKU-SE59(T) (?=BCC 61184(T)?=NBRC 109696(T)?=CBS 13389 (T)). PMID:25713048

  8. Biopharmaceutical discovery and production in yeast.

    PubMed

    Meehl, Michael A; Stadheim, Terrance A

    2014-12-01

    The selection of an expression platform for recombinant biopharmaceuticals is often centered upon suitable product titers and critical quality attributes, including post-translational modifications. Although notable differences between microbial, yeast, plant, and mammalian host systems exist, recent advances have greatly mitigated any inherent liabilities of yeasts. Yeast expression platforms are important to both the supply of marketed biopharmaceuticals and the pipelines of novel therapeutics. In this review, recent advances in yeast-based expression of biopharmaceuticals will be discussed. The advantages of using glycoengineered yeast as a production host and in the discovery space will be illustrated. These advancements, in turn, are transforming yeast platforms from simple production systems to key technological assets in the discovery and selection of biopharmaceutical lead candidates. PMID:25014890

  9. Yeasts Diversity in Fermented Foods and Beverages

    NASA Astrophysics Data System (ADS)

    Tamang, Jyoti Prakash; Fleet, Graham H.

    People across the world have learnt to culture and use the essential microorganisms for production of fermented foods and alcoholic beverages. A fermented food is produced either spontaneously or by adding mixed/pure starter culture(s). Yeasts are among the essential functional microorganisms encountered in many fermented foods, and are commercially used in production of baker's yeast, breads, wine, beer, cheese, etc. In Asia, moulds are predominant followed by amylolytic and alcohol-producing yeasts in the fermentation processes, whereas in Africa, Europe, Australia and America, fermented products are prepared exclusively using bacteria or bacteria-yeasts mixed cultures. This chapter would focus on the varieties of fermented foods and alcoholic beverages produced by yeasts, their microbiology and role in food fermentation, widely used commercial starters (pilot production, molecular aspects), production technology of some common commercial fermented foods and alcoholic beverages, toxicity and food safety using yeasts cultures and socio-economy

  10. Yeasts in floral nectar: a quantitative survey

    PubMed Central

    Herrera, Carlos M.; de Vega, Clara; Canto, Azucena; Pozo, María I.

    2009-01-01

    Background and Aims One peculiarity of floral nectar that remains relatively unexplored from an ecological perspective is its role as a natural habitat for micro-organisms. This study assesses the frequency of occurrence and abundance of yeast cells in floral nectar of insect-pollinated plants from three contrasting plant communities on two continents. Possible correlations between interspecific differences in yeast incidence and pollinator composition are also explored. Methods The study was conducted at three widely separated areas, two in the Iberian Peninsula (Spain) and one in the Yucatán Peninsula (Mexico). Floral nectar samples from 130 species (37–63 species per region) in 44 families were examined microscopically for the presence of yeast cells. For one of the Spanish sites, the relationship across species between incidence of yeasts in nectar and the proportion of flowers visited by each of five major pollinator categories was also investigated. Key Results Yeasts occurred regularly in the floral nectar of many species, where they sometimes reached extraordinary densities (up to 4 × 105 cells mm−3). Depending on the region, between 32 and 44 % of all nectar samples contained yeasts. Yeast cell densities in the order of 104 cells mm−3 were commonplace, and densities >105 cells mm−3 were not rare. About one-fifth of species at each site had mean yeast cell densities >104 cells mm−3. Across species, yeast frequency and abundance were directly correlated with the proportion of floral visits by bumble-bees, and inversely with the proportion of visits by solitary bees. Conclusions Incorporating nectar yeasts into the scenario of plant–pollinator interactions opens up a number of intriguing avenues for research. In addition, with yeasts being as ubiquitous and abundant in floral nectars as revealed by this study, and given their astounding metabolic versatility, studies focusing on nectar chemical features should carefully control for the presence of yeasts in nectar samples. PMID:19208669

  11. The yeast Golgi apparatus: insights and mysteries

    PubMed Central

    Papanikou, Effrosyni; Glick, Benjamin S.

    2009-01-01

    The Golgi apparatus is known to modify and sort newly synthesized secretory proteins. However, fundamental mysteries remain about the structure, operation, and dynamics of this organelle. Important insights have emerged from studying the Golgi in yeasts. For example, yeasts have provided direct evidence for Golgi cisternal maturation, a mechanism that is likely to be broadly conserved. Here, we highlight features of the yeast Golgi as well as challenges that lie ahead. PMID:19879270

  12. Role of glucose signaling in yeast metabolism

    SciTech Connect

    Dam, K. van

    1996-10-05

    The conversion of glucose to ethanol and carbon dioxide by yeast was the first biochemical pathway to be studied in detail. The initial observation that this process is catalyzed by an extract of yeast led to the discovery of enzymes and coenzymes and laid the foundation for modern biochemistry. In this article, knowledge concerning the relation between uptake of and signaling by glucose in the yeast Saccharomyces cerevisiae is reviewed and compared to the analogous process in prokaryotes. It is concluded that (much) more fundamental knowledge concerning these processes is required before rational redesign of metabolic fluxes from glucose in yeast can be achieved.

  13. Evaluation of Automated Yeast Identification System

    NASA Technical Reports Server (NTRS)

    McGinnis, M. R.

    1996-01-01

    One hundred and nine teleomorphic and anamorphic yeast isolates representing approximately 30 taxa were used to evaluate the accuracy of the Biolog yeast identification system. Isolates derived from nomenclatural types, environmental, and clinica isolates of known identity were tested in the Biolog system. Of the isolates tested, 81 were in the Biolog database. The system correctly identified 40, incorrectly identified 29, and was unable to identify 12. Of the 28 isolates not in the database, 18 were given names, whereas 10 were not. The Biolog yeast identification system is inadequate for the identification of yeasts originating from the environment during space program activities.

  14. 21 CFR 172.381 - Vitamin D2 bakers yeast.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... conventional bakers yeast. (c) The additive may be used in yeast-leavened baked goods and baking mixes and yeast-leavened baked snack foods at levels not to exceed 400 International Units of vitamin D2 per...

  15. YMDB: the Yeast Metabolome Database

    PubMed Central

    Jewison, Timothy; Knox, Craig; Neveu, Vanessa; Djoumbou, Yannick; Guo, An Chi; Lee, Jacqueline; Liu, Philip; Mandal, Rupasri; Krishnamurthy, Ram; Sinelnikov, Igor; Wilson, Michael; Wishart, David S.

    2012-01-01

    The Yeast Metabolome Database (YMDB, http://www.ymdb.ca) is a richly annotated ‘metabolomic’ database containing detailed information about the metabolome of Saccharomyces cerevisiae. Modeled closely after the Human Metabolome Database, the YMDB contains >2000 metabolites with links to 995 different genes/proteins, including enzymes and transporters. The information in YMDB has been gathered from hundreds of books, journal articles and electronic databases. In addition to its comprehensive literature-derived data, the YMDB also contains an extensive collection of experimental intracellular and extracellular metabolite concentration data compiled from detailed Mass Spectrometry (MS) and Nuclear Magnetic Resonance (NMR) metabolomic analyses performed in our lab. This is further supplemented with thousands of NMR and MS spectra collected on pure, reference yeast metabolites. Each metabolite entry in the YMDB contains an average of 80 separate data fields including comprehensive compound description, names and synonyms, structural information, physico-chemical data, reference NMR and MS spectra, intracellular/extracellular concentrations, growth conditions and substrates, pathway information, enzyme data, gene/protein sequence data, as well as numerous hyperlinks to images, references and other public databases. Extensive searching, relational querying and data browsing tools are also provided that support text, chemical structure, spectral, molecular weight and gene/protein sequence queries. Because of S. cervesiae's importance as a model organism for biologists and as a biofactory for industry, we believe this kind of database could have considerable appeal not only to metabolomics researchers, but also to yeast biologists, systems biologists, the industrial fermentation industry, as well as the beer, wine and spirit industry. PMID:22064855

  16. [Taxonomic genetics of Zygowilliopsis yeasts].

    PubMed

    Naumov, G I; Kondrat'eva, V I; Naumova, E S

    2009-12-01

    Genetic hybridization analysis was conducted with 16 natural Zygowilliopsis strains isolated in different geographical regions and maintained in collections under species names Z. californica, Hansenula dimennae, and Pichia populi. Genetic relatedness was determined on the basis of mating, viability of hybrid progeny, and meiotic recombination of markers. Four new biological species are recognized in the former monotypic genus Zygowilliopsis. Species Z. californica and Zygowilliopsis sp. 3 probably include divergent geographical populations. It is necessary to reconsider the species composition of the genus Zygowilliopsis and generic assignment of P. populi yeasts. Genetic and molecular identifications of the Zygowilliopsis species are in perfect agreement. PMID:20198971

  17. Isolation of Peroxisomes from Yeast.

    PubMed

    Cramer, Jana; Effelsberg, Daniel; Girzalsky, Wolfgang; Erdmann, Ralf

    2015-09-01

    Peroxisomes are multifunctional, dynamic organelles present in nearly all eukaryotic cells. Determining their structural and functional characteristics often requires obtaining isolated and purified peroxisomes via subcellular fractionation. Subcellular fractionation techniques are generally based on a three-step procedure: preparation of a cell-free homogenate (postnuclear supernatant), generation of an organellar pellet by differential centrifugation, and density gradient centrifugation. Here we introduce methods for small-scale isolation of peroxisomes from yeast cells using different gradient media as well as large-scale purification using a two-step gradient centrifugation. PMID:26330630

  18. Phosphatidic acid synthesis in yeast

    PubMed Central

    Kuhn, N. J.; Lynen, F.

    1965-01-01

    1. The presence of palmitoyl-CoA–l-glycerol 1-phosphate palmitoyltransferase (EC2.3.1.15) has been demonstrated in a particulate fraction of baker's yeast. 2. The enzyme has been characterized, and its activity studied as a function of pH and concentration of substrates. 3. Inhibition by thiol poisons and protection by acyl-CoA have been used to obtain information on the active site. 4. By various methods of supplying acyl radicals, the species `palmitoyl-CoA' has been shown to be the true acyl donor to the transferase. PMID:14342236

  19. Experimental evolution in budding yeast

    NASA Astrophysics Data System (ADS)

    Murray, Andrew

    2012-02-01

    I will discuss our progress in analyzing evolution in the budding yeast, Saccharomyces cerevisiae. We take two basic approaches. The first is to try and examine quantitative aspects of evolution, for example by determining how the rate of evolution depends on the mutation rate and the population size or asking whether the rate of mutation is uniform throughout the genome. The second is to try to evolve qualitatively novel, cell biologically interesting phenotypes and track the mutations that are responsible for the phenotype. Our efforts include trying to alter cell morphology, evolve multicellularity, and produce a biological oscillator.

  20. Involvement of Ethylene in the Latex Metabolism and Tapping Panel Dryness of Hevea brasiliensis.

    PubMed

    Putranto, Riza-Arief; Herlinawati, Eva; Rio, Maryannick; Leclercq, Julie; Piyatrakul, Piyanuch; Gohet, Eric; Sanier, Christine; Oktavia, Fetrina; Pirrello, Julien; Kuswanhadi; Montoro, Pascal

    2015-01-01

    Ethephon, an ethylene releaser, is used to stimulate latex production in Hevea brasiliensis. Ethylene induces many functions in latex cells including the production of reactive oxygen species (ROS). The accumulation of ROS is responsible for the coagulation of rubber particles in latex cells, resulting in the partial or complete stoppage of latex flow. This study set out to assess biochemical and histological changes as well as changes in gene expression in latex and phloem tissues from trees grown under various harvesting systems. The Tapping Panel Dryness (TPD) susceptibility of Hevea clones was found to be related to some biochemical parameters, such as low sucrose and high inorganic phosphorus contents. A high tapping frequency and ethephon stimulation induced early TPD occurrence in a high latex metabolism clone and late occurrence in a low latex metabolism clone. TPD-affected trees had smaller number of laticifer vessels compared to healthy trees, suggesting a modification of cambial activity. The differential transcript abundance was observed for twenty-seven candidate genes related to TPD occurrence in latex and phloem tissues for ROS-scavenging, ethylene biosynthesis and signalling genes. The predicted function for some Ethylene Response Factor genes suggested that these candidate genes should play an important role in regulating susceptibility to TPD. PMID:26247941

  1. Fat content in migratory central Arizona Brazilian free-tailed bats, Tadarida brasiliensis (Molossidae)

    USGS Publications Warehouse

    O'Shea, Thomas J.

    1976-01-01

    Fat content of migratory Tadarida brasiliensis was determined during the spring, summer and fall of 1972 in the Verde Valley of Arizona. Fat indices were highest in March arrivals, generally declined throughout the summer, and were lowest in September. In both 1972 and 1973 bats had arrived at the study area by mid-March. In 1971 bats were last noted at the area in mid-October while in 1972 they had disappeared by late September. On the basis on physiological calculations it is estimated that bats collected in March 1972 possessed sufficient fat reserves to carry them a mean distance of 716 km north of the study area while September bats had only enough reserves to fly 386 km southward, about 160 km short of the nearest known Sonora wintering locality. It is suggested that in spring the bats may have a more rigidly timed migration and so put on excess fat to counter an uncertain environment to the north. The fall migration may be triggered by more unpredictable events, such as the passage of cold fronts, and less fat reserves may be required for movements into more favorable southern locales.

  2. Sporothrix brasiliensis, S. globosa, and S. mexicana, Three New Sporothrix Species of Clinical Interest?

    PubMed Central

    Marimon, Rita; Cano, Josep; Gené, Josepa; Sutton, Deanna A.; Kawasaki, Masako; Guarro, Josep

    2007-01-01

    Sporothrix schenckii is the species responsible for sporotrichosis, a fungal infection caused by the traumatic implantation of this dimorphic fungus. Recent molecular studies have demonstrated that this species constitutes a complex of numerous phylogenetic species. Since the delineation of such species could be of extreme importance from a clinical point of view, we have studied a total of 127 isolates, most of which were received as S. schenckii, including the available type strains of species currently considered synonyms, and also some close morphological species. We have phenotypically characterized all these isolates using different culture media, growth rates at different temperatures, and numerous nutritional tests and compared their calmodulin gene sequences. The molecular analysis revealed that Sporothrix albicans, S. inflata, and S. schenckii var. luriei are species that are clearly different from S. schenckii. The combination of these phenetic and genetic approaches allowed us to propose the new species Sporothrix brasiliensis, S. globosa, and S. mexicana. The key phenotypic features for recognizing these species are the morphology of the sessile pigmented conidia, growth at 30, 35, and 37°C, and the assimilation of sucrose, raffinose, and ribitol. PMID:17687013

  3. Metazoan parasites of Geophagus brasiliensis (Perciformes: Cichlidae) in Patos lagoon, extreme south of Brazil.

    PubMed

    Rassier, Gabriela Lopes; Pesenti, Tatiana Cheuiche; Pereira Júnior, Joaber; Silva, Diego Silva da; Wendt, Emília Welter; Monteiro, Cassandra de Moraes; Berne, Maria Elizabeth Aires

    2015-12-01

    This study has evaluated the parasitic fauna of 79 pearl cichlids (Geophagus brasiliensis) from the estuary of Patos Lagoon (31° 57' S and 52° 06' W), Rio Grande do Sul, Brazil, during the months of May and June in 2011 and 2012. All the hosts analyzed were infected with at least one species of parasite. A total of eleven metazoa were identified in 459 specimens collected. The trematode Austrodiplostomum compactum (34.2%) and ergasilids Ergasilus lizae (32.9%) and Gauchergasilus lizae (32.9%) were the most prevalent species. The trematodes Thometrema overstreeti and Posthodiplostomum sp. had significantly higher prevalence in fish longer than 20 cm. The sex of the host had no effect on parasite prevalence and abundance. Pearl cichlids are registered as a new host for the trematodes Lobatostoma sp., Homalometron pseudopallidum and Thometrema overstreeti, for the ergasilids Ergasilus lizae and Gauchergasilus euripedesi and for the argulid Argulus spinolosus. The crustacean E. lizae is recorded in Rio Grande do Sul for the first time. PMID:26648010

  4. Effects of DDE on experimentally poisoned free-tailed bats (Tadarida brasiliensis): Lethal brain concentrations

    USGS Publications Warehouse

    Clark, D.R., Jr.; Kroll, J.C.

    1977-01-01

    Adult female free-tailed bats (Tadarida brasiliensis) were collected at Bracken Cave, Texas, and shipped to the Patuxent Wildlife Research Center. Treated mealworms (Tenebrio molitor) containing 107 ppm DDE were fed to 17 bats; five other bats were fed untreated mealworms. After 40 days on dosage, during which one dosed bat was killed accidentally, four dosed bats were frozen and the remaining 17 were starved to death. The objective was to elevate brain levels of DDE to lethality and measure these concentrations. After the feeding period, dosed bats weighed less than controls. After starvation, the body condition of dosed bats was poorer than that of controls even though there was no difference in the amounts of carcass fat. During starvation, dosed bats lost weight faster than controls. Also, four dosed bats exhibited the prolonged tremoring that characterizes DDE poisoning. DDE increased in brains of starving bats as fat was metabolized. The estimated mean brain concentration of DDE diagnostic of death was 519 ppm with a range of 458-564 ppm. These values resemble diagnostic levels known for two species of passerine birds, but they exceed published levels for two free-tailed bats from Carlsbad Caverns, New Mexico.

  5. Evolutionary history and identification of conservation units in the giant otter, Pteronura brasiliensis.

    PubMed

    Pickles, R S A; Groombridge, J J; Zambrana Rojas, V D; Van Damme, P; Gottelli, D; Kundu, S; Bodmer, R; Ariani, C V; Iyengar, A; Jordan, W C

    2011-12-01

    The giant otter, Pteronura brasiliensis, occupies a range including the major drainage basins of South America, yet the degree of structure that exists within and among populations inhabiting these drainages is unknown. We sequenced portions of the mitochondrial DNA (mtDNA) cytochrome b (612bp) and control region (383 bp) genes in order to determine patterns of genetic variation within the species. We found high levels of mtDNA haplotype diversity (h = 0.93 overall) and support for subdivision into four distinct groups of populations, representing important centers of genetic diversity and useful units for prioritizing conservation within the giant otter. We tested these results against the predictions of three hypotheses of Amazonian diversification (Pleistocene Refugia, Paleogeography, and Hydrogeology). While the phylogeographic pattern conformed to the predictions of the Refugia Hypothesis, molecular dating using a relaxed clock revealed the phylogroups diverged from one another between 1.69 and 0.84 Ma, ruling out the influence of Late Pleistocene glacial refugia. However, the role of Plio-Pleistocene climate change could not be rejected. While the molecular dating also makes the influence of geological arches according to the Paleogeography Hypothesis extremely unlikely, the recent Pliocene formation of the Fitzcarrald Arch and its effect of subsequently altering drainage pattern could not be rejected. The data presented here support the interactions of both climatic and hydrological changes resulting from geological activity in the Plio-Pleistocene, in shaping the phylogeographic structure of the giant otter. PMID:21925282

  6. Aid to a Declining Matriarch in the Giant Otter (Pteronura brasiliensis)

    PubMed Central

    Davenport, Lisa C.

    2010-01-01

    Scientists are increasingly revealing the commonalities between the intellectual, emotional and moral capacities of animals and humans. Providing assistance to elderly and ailing family members is a human trait rarely documented for wild animals, other than anecdotal accounts. Here I report observations of multiple forms of assistance to the declining matriarch of a habituated group of giant otters (Pteronura brasiliensis) in Manu National Park, Peru. The otter group had been observed annually for several years and all members were known individually. In 2007, the breeding female of the group failed to reproduce and appeared to be in physical decline. She begged from other family members 43 times over 41 contact hours and received food 11 times. Comparisons with 2004–2006 demonstrate that the family's behavior in 2007 constitutes a role-reversal, in which the majority of assistance and prey transfers accrued from young-to-old rather than from old-to-young. As in human societies, both non-adaptive and adaptive hypotheses could explain the family members' aid to their declining matriarch. I suggest that giant otter families may benefit from the knowledge and experience of an elderly matriarch and “grandparent helper,” consistent with the “Grandmother Hypothesis” of adaptive menopause in women. PMID:20613978

  7. Rubber elongation factor (REF), a major allergen component in Hevea brasiliensis latex has amyloid properties.

    PubMed

    Berthelot, Karine; Lecomte, Sophie; Estevez, Yannick; Coulary-Salin, Bénédicte; Bentaleb, Ahmed; Cullin, Christophe; Deffieux, Alain; Peruch, Frédéric

    2012-01-01

    REF (Hevb1) and SRPP (Hevb3) are two major components of Hevea brasiliensis latex, well known for their allergenic properties. They are obviously taking part in the biosynthesis of natural rubber, but their exact function is still unclear. They could be involved in defense/stress mechanisms after tapping or directly acting on the isoprenoid biosynthetic pathway. The structure of these two proteins is still not described. In this work, it was discovered that REF has amyloid properties, contrary to SRPP. We investigated their structure by CD, TEM, ATR-FTIR and WAXS and neatly showed the presence of β-sheet organized aggregates for REF, whereas SRPP mainly fold as a helical protein. Both proteins are highly hydrophobic but differ in their interaction with lipid monolayers used to mimic the monomembrane surrounding the rubber particles. Ellipsometry experiments showed that REF seems to penetrate deeply into the monolayer and SRPP only binds to the lipid surface. These results could therefore clarify the role of these two paralogous proteins in latex production, either in the coagulation of natural rubber or in stress-related responses. To our knowledge, this is the first report of an amyloid formed from a plant protein. This suggests also the presence of functional amyloid in the plant kingdom. PMID:23133547

  8. Rubber Elongation Factor (REF), a Major Allergen Component in Hevea brasiliensis Latex Has Amyloid Properties

    PubMed Central

    Berthelot, Karine; Lecomte, Sophie; Estevez, Yannick; Coulary-Salin, Bénédicte; Bentaleb, Ahmed; Cullin, Christophe; Deffieux, Alain; Peruch, Frédéric

    2012-01-01

    REF (Hevb1) and SRPP (Hevb3) are two major components of Hevea brasiliensis latex, well known for their allergenic properties. They are obviously taking part in the biosynthesis of natural rubber, but their exact function is still unclear. They could be involved in defense/stress mechanisms after tapping or directly acting on the isoprenoid biosynthetic pathway. The structure of these two proteins is still not described. In this work, it was discovered that REF has amyloid properties, contrary to SRPP. We investigated their structure by CD, TEM, ATR-FTIR and WAXS and neatly showed the presence of β-sheet organized aggregates for REF, whereas SRPP mainly fold as a helical protein. Both proteins are highly hydrophobic but differ in their interaction with lipid monolayers used to mimic the monomembrane surrounding the rubber particles. Ellipsometry experiments showed that REF seems to penetrate deeply into the monolayer and SRPP only binds to the lipid surface. These results could therefore clarify the role of these two paralogous proteins in latex production, either in the coagulation of natural rubber or in stress-related responses. To our knowledge, this is the first report of an amyloid formed from a plant protein. This suggests also the presence of functional amyloid in the plant kingdom. PMID:23133547

  9. Antiproliferative effects of lectins from Canavalia ensiformis and Canavalia brasiliensis in human leukemia cell lines.

    PubMed

    Faheina-Martins, Glaucia V; da Silveira, Alethéia Lacerda; Cavalcanti, Bruno C; Ramos, Márcio V; Moraes, Manoel O; Pessoa, Cláudia; Araújo, Demetrius A M

    2012-10-01

    The antiproliferative activity of lectins Canavalia ensiformis (ConA) and Canavalia brasiliensis (ConBr) were studied using human leukemia MOLT-4 and HL-60 cell lines. It was revealed that both ConA and ConBr were markedly cytotoxic to cells using MTT and NAC assays. The IC(50) values were approximately 3 and 20 ?g/mL for ConA and ConBr, respectively, for both MOLT-4 and HL-60 cells. However, in normal human peripheral blood lymphocytes, the lectins were not cytotoxic, even when tested at concentrations as high as 200 ?g/ml. Using comet assay, the lectins produced a rate of DNA damage exceeding 80% in MOLT-4 and HL-60 cells. Fluorescence analysis revealed the morphology characteristic of apoptosis, with low concentrations of apoptotic bodies and fragmented DNA (5 ?g/ml). Flow cytometric analysis demonstrated an accumulation of cells in the sub-G1 cell cycle that is characteristic of DNA fragmentation, and a decrease in membrane integrity at high concentrations. Lastly, we evaluated the alterations in mitochondrial potential that reduced after treatment with lectins. Our results indicate that ConA and ConBr inhibited cell proliferation selectively in tumor cells and that apoptosis was the main death mechanism. Therefore, lectins can be considered a class of molecules with a high antitumor activity potential. PMID:22776218

  10. The acute phase response in parasite infection. Nippostrongylus brasiliensis in the mouse.

    PubMed Central

    Lamontagne, L R; Gauldie, J; Befus, A D; McAdam, K P; Baltz, M L; Pepys, M B

    1984-01-01

    Systemic inflammatory reactions are a prominent feature of many parasitic infections and the cellular and humoral components of the acute phase reaction may have an impact on the host-parasite relationship. We examined serum changes of four acute phase reactants: alpha 1-proteinase inhibition (alpha 1Pi); complement C3; serum amyloid A protein (SAA); and serum amyloid P component (SAP), in mice undergoing a primary infection with Nippostrongylus brasiliensis. SAA and SAP showed changes within the first 2 days of infection indicating the presence of an acute phase response associated with inflammation in the lung. Alpha 1Pi and C3 serum levels were not altered. However, all four acute phase reactants were synthesized in greater amounts by primary cultures of hepatocytes taken from infected animals at this time. Subsequently, as parasite-mediated inflammatory changes occur in the gut, both serum and hepatocyte cultures demonstrate an acute inflammatory response in all four reactants. It is proposed that the early reaction between parasites and macrophage/monocyte lead to the release of a mediator of inflammation which initiates the hepatocyte response. In this infection, at least one of the APR is shown to localize to the site of inflammation influencing the host-parasite relationship. Images Figure 2 Figure 3 PMID:6204934

  11. Changes in the Chemical Composition and Decay Resistance of Thermally-Modified Hevea brasiliensis Wood

    PubMed Central

    2016-01-01

    In this study the effect of thermal treatment on the equilibrium moisture content, chemical composition and biological resistance to decay fungi of juvenile and mature Hevea brasiliensis wood (rubber wood) was evaluated. Samples were taken from a 53-year-old rubber wood plantation located in Tabapuã, Sao Paulo, Brazil. The samples were thermally-modified at 180°C, 200°C and 220°C. Results indicate that the thermal modification caused: (1) a significant increase in the extractive content and proportional increase in the lignin content at 220°C; (2) a significant decrease in the equilibrium moisture content, holocelluloses, arabinose, galactose and xylose content, but no change in glucose content; and (3) a significant increase in wood decay resistance against both Pycnoporus sanguineus (L.) Murrill and Gloeophyllum trabeum (Pers.) Murrill decay fungi. The greatest decay resistance was achieved from treatment at 220°C which resulted in a change in wood decay resistance class from moderately resistant to resistant. Finally, this study also demonstrated that the influence of thermal treatment in mature wood was lower than in juvenile wood. PMID:26986200

  12. Diversity of the cassiicolin gene in Corynespora cassiicola and relation with the pathogenicity in Hevea brasiliensis.

    PubMed

    Déon, Marine; Fumanal, Boris; Gimenez, Stéphanie; Bieysse, Daniel; Oliveira, Ricardo R; Shuib, Siti Shuhada; Breton, Frédéric; Elumalai, Sunderasan; Vida, João B; Seguin, Marc; Leroy, Thierry; Roeckel-Drevet, Patricia; Pujade-Renaud, Valérie

    2014-01-01

    Corynespora cassiicola is an important plant pathogenic Ascomycete causing the damaging Corynespora Leaf Fall (CLF) disease in rubber tree (Hevea brasiliensis). A small secreted glycoprotein named cassiicolin was previously described as an important effector of C. cassiicola. In this study, the diversity of the cassiicolin-encoding gene was analysed in C. cassiicola isolates sampled from various hosts and geographical origins. A cassiicolin gene was detected in 47 % of the isolates, encoding up to six distinct protein isoforms. In three isolates, two gene variants encoding cassiicolin isoforms Cas2 and Cas6 were found in the same isolate. A phylogenetic tree based on four combined loci and elucidating the diversity of the whole collection was strongly structured by the toxin class, as defined by the cassiicolin isoform. The isolates carrying the Cas1 gene (toxin class Cas1), all grouped in the same highly supported clade, were found the most aggressive on two rubber tree cultivars. Some isolates in which no Cas gene was detected could nevertheless generate moderate symptoms, suggesting the existence of other yet uncharacterized effectors. This study provides a useful base for future studies of C. cassiicola population biology and epidemiological surveys in various host plants. PMID:24433675

  13. The reversibility of intestinal immune expulsion effects on adult Nippostrongylus brasiliensis.

    PubMed

    Kassai, T; Takáts, C; Redl, P

    1987-04-01

    An attempt has been made to study the extent and nature of the damage occurring in adult Nippostrongylus brasiliensis undergoing immune expulsion from the rat. It was found that worms are not killed nor irreparably damaged when being rejected. On transfer into naive second recipient rats the rate of re-establishment of worms previously incubated in immune rat recipients for 4-17 hr was high (68-69%) and comparable to that shown by worms from normal recipient rats (48-56%). Similarly, worms taken on days 10, 11, and 12 of a primary infection, already passed to the distal half of the small intestine due to immune expulsion effects, on transfer into naive recipient rats re-established themselves well (rates varying from 62 to 80%) compared to those harvested from their normal habitat in the proximal half of the small intestine (rates varying from 44 to 87%). Worm damage is associated with decreased motility and impaired locomotion capacity. The phenomenon of mucosal trapping occurs during expulsion, but merely to the extent of some 30% of the worm population. It is suggested that in principle, worms subjected to immune expulsion are in a state of acute, transient metabolic crisis. The present results support the enteroallergic indirect mechanism for worm rejection. PMID:3585631

  14. Entomopathogenic fungi, Metarhizium anisopliae and Beauveria bassiana reduce the survival of Xenopsylla brasiliensis larvae (Siphonaptera: Pulicidae)

    PubMed Central

    2012-01-01

    Background Entomopathogenic fungi, particularly those belonging to the genera Metarhizium and Beauveria have shown great promise as arthropod vector control tools. These agents, however, have not been evaluated against flea vectors of plague. Findings A 3-h exposure to the fungi coated paper at a concentration of 2 × 108 conidia m-2 infected >90% of flea larvae cadavers in the treatment groups. The infection reduced the survival of larvae that had been exposed to fungus relative to controls. The daily risk of dying was four- and over three-fold greater in larvae exposed to M. anisopliae (HR = 4, p<0.001) and B. bassiana (HR = 3.5, p<0.001) respectively. Both fungi can successfully infect and kill larvae of X. brasiliensis with a pooled median survival time (MST±SE) of 2±0.31 days post-exposure. Conclusion These findings justify further research to investigate the bio-control potential of entomopathogenic fungi against fleas. PMID:22992264

  15. Rubber (Hevea brasiliensis) seed oil toxicity effect and Linamarin compound analysis

    PubMed Central

    2012-01-01

    Background The lipid fraction of rubber (Hevea brasiliensis (kunth. Muell)) seed was extracted and analyzed for toxicological effect. The toxicological compound such as linamarin in rubber seed oil (RSO) extracted using different solvents, such as hexane (RSOh), mixture of chloroform + methanol (RSOchl+mth) and ethanol (RSOeth) were also studied. Various methods analysis such as Fourier transforms infrared spectroscopy (FTIR) and colorimetric methods were carried out to determine the present of such compounds. Results FTIR spectrum of RSO did not show any presence of cyanide peak. The determination of cyanide by using colorimetric method was demonstrated no response of the cyanide in RSO and didn’t show any colored comparing with commercial cyanide which observed blue color. The results showed that no functional groups such as cyanide (C ≡ N) associated with linamarin were observed. Toxicological test using rats was also conducted to further confirm the absence of such compounds. RSO did not show any toxic potential to the rats. Bioassay experiments using shrimps had been used as test organisms to evaluate the toxicity of linamarin extract from RSOh, RSOchl+mth and RSOeth and LC50 were found to be (211.70 %, 139.40 %, and 117.41 %, respectively). Conclusions This can be attributed no hazardous linamarin were found in RSO. PMID:22694753

  16. Genetic and epigenetic uniformity of polyembryony derived multiple seedlings of Hevea brasiliensis.

    PubMed

    Karumamkandathil, Rekha; Uthup, Thomas K; Sankaran, Sobha; Unnikrishnan, Divya; Saha, Thakurdas; Nair, Sushamakumari S

    2015-05-01

    Hevea brasiliensis Muell. Arg (Para rubber tree) is a tropical tree species of Amazonian origin widely cultivated in several parts of the world for natural rubber, a highly priced commodity inevitable for the world rubber industry. Large, tree to tree variation in growth and latex yield among individual plants of high yielding Hevea clones is a common phenomenon observed in mature rubber plantations. The genetic heterogeneity of the seedlings which are used as rootstocks for propagation through budgrafting is considered as a major factor responsible for this variation. In order to minimize this variation, attempts were made to develop highly uniform rootstock material via an in vitro technique by inducing zygotic polyembryony in Hevea. Immature open pollinated fruits of a high yielding clone RRII 105 were cultured by half ovulo embryo culture technique. Multiple embryos were induced from the 8-10-week-old zygote with a novel combination of gibberellic acid (GA3), kinetin, and zeatin. Plantlets were successfully generated from the multiple embryos and raised in the field post hardening. Screening using genetic and epigenetic molecular markers revealed that the multiple seedlings developed are highly uniform and are of single zygotic origin. Development of plants having genetic and epigenetic uniformity suggests that this technique is ideal for raising uniform rootstock material in Hevea which may significantly reduce intraclonal variations. Moreover, these plants could serve as ideal material for physiological and molecular investigations towards the understanding of stock-scion interaction process in rubber. PMID:25359186

  17. In vitro and in vivo photoprotective/photochemopreventive potential of Garcinia brasiliensis epicarp extract.

    PubMed

    Figueiredo, Sônia Aparecida; Vilela, Fernanda Maria Pinto; da Silva, Claudinei Alves; Cunha, Thiago Mattar; Dos Santos, Marcelo Henrique; Fonseca, Maria José Vieira

    2014-02-01

    The damaging effects of sunlight to the skin has triggered studies that involve the synthesis and extraction of organic compounds from natural sources that can absorb UV radiation, and studies on polyphenolic compounds with antioxidant and anti-inflammatory properties that can be used as photochemopreventive agents for reducing skin damage. We investigated the in vitro and in vivo photoprotective/photochemopreventive potential of Garcinia brasiliensis epicarp extract (GbEE). We evaluated the cell viability of L929 fibroblasts after UVB exposure using a quartz plate containing the extract solution or the GbEE formulation. The in vivo photoprotective effect of the GbEE formulation was evaluated by measuring the UVB damage-induced decrease in endogenous reduced glutathione (GSH), the increase in myeloperoxidase (MPO) activity and secretion of cytokines IL-1β and TNF-α. The in vitro methodology using fibroblasts showed that the photoprotective properties of the GbEE solutions and 10% GbEE formulation were similar to the commercial sunscreen (SPF-15). In vivo results demonstrated of the GbEE formulation in decreasing UVB induced-damage such as GSH depletion, an increased in MPO activity and secretion of cytokines IL-1β and TNF-α. The results showed that the extract has great potential for use as a sunscreen in topical formulations in addition to UV filters. PMID:24491421

  18. Hevea brasiliensis cell suspension peroxidase: purification, characterization and application for dye decolorization

    PubMed Central

    2013-01-01

    Peroxidases are oxidoreductase enzymes produced by most organisms. In this study, a peroxidase was purified from Hevea brasiliensis cell suspension by using anion exchange chromatography (DEAE-Sepharose), affinity chromatography (Con A-agarose) and preparative SDS-PAGE. The obtained enzyme appeared as a single band on SDS-PAGE with molecular mass of 70 kDa. Surprisingly, this purified peroxidase also had polyphenol oxidase activity. However, the biochemical characteristics were only studied in term of peroxidase because similar experiments in term of polyphenol oxidase have been reported in our pervious publication. The optimal pH of the purified peroxidase was 5.0 and its activity was retained at pH values between 5.0–10.0. The enzyme was heat stable over a wide range of temperatures (0–60°C), and less than 50% of its activity was lost at 70°C after incubation for 30 min. The enzyme was completely inhibited by β-mercaptoethanol and strongly inhibited by NaN3; in addition, its properties indicated that it was a heme containing glycoprotein. This peroxidase could decolorize many dyes; aniline blue, bromocresol purple, brilliant green, crystal violet, fuchsin, malachite green, methyl green, methyl violet and water blue. The stability against high temperature and extreme pH supported that the enzyme could be a potential peroxidase source for special industrial applications. PMID:23402438

  19. Involvement of Ethylene in the Latex Metabolism and Tapping Panel Dryness of Hevea brasiliensis

    PubMed Central

    Putranto, Riza-Arief; Herlinawati, Eva; Rio, Maryannick; Leclercq, Julie; Piyatrakul, Piyanuch; Gohet, Eric; Sanier, Christine; Oktavia, Fetrina; Pirrello, Julien; Kuswanhadi; Montoro, Pascal

    2015-01-01

    Ethephon, an ethylene releaser, is used to stimulate latex production in Hevea brasiliensis. Ethylene induces many functions in latex cells including the production of reactive oxygen species (ROS). The accumulation of ROS is responsible for the coagulation of rubber particles in latex cells, resulting in the partial or complete stoppage of latex flow. This study set out to assess biochemical and histological changes as well as changes in gene expression in latex and phloem tissues from trees grown under various harvesting systems. The Tapping Panel Dryness (TPD) susceptibility of Hevea clones was found to be related to some biochemical parameters, such as low sucrose and high inorganic phosphorus contents. A high tapping frequency and ethephon stimulation induced early TPD occurrence in a high latex metabolism clone and late occurrence in a low latex metabolism clone. TPD-affected trees had smaller number of laticifer vessels compared to healthy trees, suggesting a modification of cambial activity. The differential transcript abundance was observed for twenty-seven candidate genes related to TPD occurrence in latex and phloem tissues for ROS-scavenging, ethylene biosynthesis and signalling genes. The predicted function for some Ethylene Response Factor genes suggested that these candidate genes should play an important role in regulating susceptibility to TPD. PMID:26247941

  20. Molecular model for studying the uncultivated fungal pathogen Lacazia loboi.

    PubMed

    Vilela, Raquel; Mendoza, Leonel; Rosa, Patricia S; Belone, Andréa Faria Fernandes; Madeira, Suzana; Opromolla, Diltor Vladimir Araújo; de Resende, Maria Aparecida

    2005-08-01

    Lacazia loboi is an uncultivated fungal pathogen of humans and dolphins that causes cutaneous and subcutaneous infections only in the tropical areas of the Americas. It was recently found by phylogenetic analysis that this unusual pathogen is closely related to Paracoccidioides brasiliensis and to the other fungal dimorphic members of the order Onygenales. That original phylogenetic study used universal primers to amplify well-known genes. However, this approach cannot be applied to the study of other proteins. We have developed a strategy for studying the gene encoding the gp43 homologous protein of P. brasiliensis in L. loboi. The gp43 protein was selected because it has been found that this P. brasiliensis antigen strongly reacts when it is used to test sera from patients with lacaziosis. The principle behind this idea was to obtain the gp43 amino acid sequence of P. brasiliensis and other homologous fungal sequences from GenBank and design primers from their aligned conserved regions. These sets of primers were used to amplify the selected regions with genomic DNA extracted from the yeast-like cells of L. loboi from experimentally infected mice. Using this approach, we amplified 483 bp of the L. loboi gp43-like gene. These sequences had 85% identity at the nucleotide level and 75% identity with the deduced amino acid sequences of the P. brasiliensis gp43 protein. The identity of the 483-bp DNA fragment was confirmed by phylogenetic analysis. This analysis revealed that the L. loboi gp43-like deduced amino acid sequence formed a strongly supported (100%) sister group with several P. brasiliensis gp43 sequences and that this taxon in turn was linked to the other fungal sequences used in this analysis. This study shows that the use of a molecular model for investigation of the genes encoding important proteins in L. loboi is feasible. PMID:16081893

  1. Prevention of Yeast Spoilage in Feed and Food by the Yeast Mycocin HMK

    PubMed Central

    Lowes, K. F.; Shearman, C. A.; Payne, J.; MacKenzie, D.; Archer, D. B.; Merry, R. J.; Gasson, M. J.

    2000-01-01

    The yeast Williopsis mrakii produces a mycocin or yeast killer toxin designated HMK; this toxin exhibits high thermal stability, high pH stability, and a broad spectrum of activity against other yeasts. We describe construction of a synthetic gene for mycocin HMK and heterologous expression of this toxin in Aspergillus niger. Mycocin HMK was fused to a glucoamylase protein carrier, which resulted in secretion of biologically active mycocin into the culture media. A partial purification protocol was developed, and a comparison with native W. mrakii mycocin showed that the heterologously expressed mycocin had similar physiological properties and an almost identical spectrum of biological activity against a number of yeasts isolated from silage and yoghurt. Two food and feed production systems prone to yeast spoilage were used as models to assess the ability of mycocin HMK to act as a biocontrol agent. The onset of aerobic spoilage in mature maize silage was delayed by application of A. niger mycocin HMK on opening because the toxin inhibited growth of the indigenous spoilage yeasts. This helped maintain both higher lactic acid levels and a lower pH. In yoghurt spiked with dairy spoilage yeasts, A. niger mycocin HMK was active at all of the storage temperatures tested at which yeast growth occurred, and there was no resurgence of resistant yeasts. The higher the yeast growth rate, the more effective the killing action of the mycocin. Thus, mycocin HMK has potential applications in controlling both silage spoilage and yoghurt spoilage caused by yeasts. PMID:10698773

  2. Fermentation studies using Saccharomyces diastaticus yeast strains

    SciTech Connect

    Erratt, J.A.; Stewart, G.G.

    1981-01-01

    The yeast species, Saccharomyces diastaticus, has the ability to ferment starch and dextrin, because of the extracellular enzyme, glucoamylase, which hydrolyzes the starch/dextrin to glucose. A number of nonallelic genes--DEX 1, DEX 2, and dextrinase B which is allelic to STA 3--have been isolated, which impart to the yeast the ability to ferment dextrin. Various diploid yeast strains were constructed, each being either heterozygous or homozygous for the individual dextrinase genes. Using 12 (sup 0) plato hopped wort (30% corn adjunct) under agitated conditions, the fermentation rates of the various diploid yeast strains were monitored. A gene-dosage effect was exhibited by yeast strains containing DEX 1 or DEX 2, however, not with yeast strains containing dextrinase B (STA 3). The fermentation and growth rates and extents were determined under static conditions at 14.4 C and 21 C. With all yeast strains containing the dextrinase genes, both fermentation and growth were increased at the higher incubation temperature. Using 30-liter fermentors, beer was produced with the various yeast strains containing the dextrinase genes and the physical and organoleptic characteristics of the products were determined. The concentration of glucose in the beer was found to increase during a 3-mo storage period at 21 C, indicating that the glucoamylase from Saccharomyces diastaticus is not inactivated by pasteurization. (Refs. 36).

  3. [Glucuronate media for isolating tremelloid yeasts].

    PubMed

    Golubev, V I

    2000-01-01

    D-Glucuronate-containing agar is suggested for evaluation the population density and diversity of tremelloid yeasts in natural cenoses. This medium is superior to the commonly used wort agar on which many representatives of tremelloid yeasts cannot be revealed. PMID:11008697

  4. Yeast: An Experimental Organism for Modern Biology.

    ERIC Educational Resources Information Center

    Botstein, David; Fink, Gerald R.

    1988-01-01

    Discusses the applicability and advantages of using yeasts as popular and ideal model systems for studying and understanding eukaryotic biology at the cellular and molecular levels. Cites experimental tractability and the cooperative tradition of the research community of yeast biologists as reasons for this success. (RT)

  5. 21 CFR 73.355 - Phaffia yeast.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... stabilized color additive mixture. Color additive mixtures for fish feed use made with phaffia yeast may... § 501.4 of this chapter. (3) The presence of the color additive in salmonid fish that have been fed... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.355 Phaffia yeast. (a) Identity. (1) The color...

  6. 21 CFR 73.355 - Phaffia yeast.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... stabilized color additive mixture. Color additive mixtures for fish feed use made with phaffia yeast may... § 501.4 of this chapter. (3) The presence of the color additive in salmonid fish that have been fed... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.355 Phaffia yeast. (a) Identity. (1) The color...

  7. 21 CFR 73.355 - Phaffia yeast.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... stabilized color additive mixture. Color additive mixtures for fish feed use made with phaffia yeast may... § 501.4 of this chapter. (3) The presence of the color additive in salmonid fish that have been fed... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.355 Phaffia yeast. (a) Identity. (1) The color...

  8. 21 CFR 73.355 - Phaffia yeast.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... stabilized color additive mixture. Color additive mixtures for fish feed use made with phaffia yeast may... § 501.4 of this chapter. (3) The presence of the color additive in salmonid fish that have been fed... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.355 Phaffia yeast. (a) Identity. (1) The color...

  9. The wine and beer yeast Dekkera bruxellensis

    PubMed Central

    Schifferdecker, Anna Judith; Dashko, Sofia; Ishchuk, Olena P; Piškur, Jure

    2014-01-01

    Recently, the non-conventional yeast Dekkera bruxellensis has been gaining more and more attention in the food industry and academic research. This yeast species is a distant relative of Saccharomyces cerevisiae and is especially known for two important characteristics: on the one hand, it is considered to be one of the main spoilage organisms in the wine and bioethanol industry; on the other hand, it is 'indispensable' as a contributor to the flavour profile of Belgium lambic and gueuze beers. Additionally, it adds to the characteristic aromatic properties of some red wines. Recently this yeast has also become a model for the study of yeast evolution. In this review we focus on the recently developed molecular and genetic tools, such as complete genome sequencing and transformation, to study and manipulate this yeast. We also focus on the areas that are particularly well explored in this yeast, such as the synthesis of off-flavours, yeast detection methods, carbon metabolism and evolutionary history. © 2014 The Authors. Yeast published by John Wiley & Sons, Ltd. PMID:24932634

  10. Yeasts are essential for cocoa bean fermentation.

    PubMed

    Ho, Van Thi Thuy; Zhao, Jian; Fleet, Graham

    2014-03-17

    Cocoa beans (Theobroma cacao) are the major raw material for chocolate production and fermentation of the beans is essential for the development of chocolate flavor precursors. In this study, a novel approach was used to determine the role of yeasts in cocoa fermentation and their contribution to chocolate quality. Cocoa bean fermentations were conducted with the addition of 200ppm Natamycin to inhibit the growth of yeasts, and the resultant microbial ecology and metabolism, bean chemistry and chocolate quality were compared with those of normal (control) fermentations. The yeasts Hanseniaspora guilliermondii, Pichia kudriavzevii and Kluyveromyces marxianus, the lactic acid bacteria Lactobacillus plantarum and Lactobacillus fermentum and the acetic acid bacteria Acetobacter pasteurianus and Gluconobacter frateurii were the major species found in the control fermentation. In fermentations with the presence of Natamycin, the same bacterial species grew but yeast growth was inhibited. Physical and chemical analyses showed that beans fermented without yeasts had increased shell content, lower production of ethanol, higher alcohols and esters throughout fermentation and lesser presence of pyrazines in the roasted product. Quality tests revealed that beans fermented without yeasts were purplish-violet in color and not fully brown, and chocolate prepared from these beans tasted more acid and lacked characteristic chocolate flavor. Beans fermented with yeast growth were fully brown in color and gave chocolate with typical characters which were clearly preferred by sensory panels. Our findings demonstrate that yeast growth and activity were essential for cocoa bean fermentation and the development of chocolate characteristics. PMID:24462702

  11. Nucleotide excision repair in yeast.

    PubMed

    Prakash, S; Prakash, L

    2000-06-30

    In nucleotide excision repair (NER) in eukaryotes, DNA is incised on both sides of the lesion, resulting in the removal of a fragment approximately 25-30 nucleotides long. This is followed by repair synthesis and ligation. The proteins encoded by the various yeast NER genes have been purified, and the incision reaction reconstituted in vitro. This reaction requires the damage binding factors Rad14, RPA, and the Rad4-Rad23 complex, the transcription factor TFIIH which contains the two DNA helicases Rad3 and Rad25, essential for creating a bubble structure, and the two endonucleases, the Rad1-Rad10 complex and Rad2, which incise the damaged DNA strand on the 5'- and 3'-side of the lesion, respectively. Addition of the Rad7-Rad16 complex to this reconstituted system stimulates the incision reaction many fold. The various NER proteins exist in vivo as part of multiprotein subassemblies which have been named NEFs (nucleotide excision repair factors). Rad14 and Rad1-Rad10 form one subassembly called NEF1, the Rad4-Rad23 complex is named NEF2, Rad2 and TFIIH constitute NEF3, and the Rad7-Rad16 complex is called NEF4. Although much has been learned from yeast about the function of NER genes and proteins in eukaryotes, the underlying mechanisms by which damage is recognized, NEFs are assembled at the damage site, and the DNA is unwound and incised, remain to be elucidated. PMID:10915862

  12. Growing yeast into cylindrical colonies.

    PubMed

    Vulin, Clément; Di Meglio, Jean-Marc; Lindner, Ariel B; Daerr, Adrian; Murray, Andrew; Hersen, Pascal

    2014-05-20

    Microorganisms often form complex multicellular assemblies such as biofilms and colonies. Understanding the interplay between assembly expansion, metabolic yield, and nutrient diffusion within a freely growing colony remains a challenge. Most available data on microorganisms are from planktonic cultures, due to the lack of experimental tools to control the growth of multicellular assemblies. Here, we propose a method to constrain the growth of yeast colonies into simple geometric shapes such as cylinders. To this end, we designed a simple, versatile culture system to control the location of nutrient delivery below a growing colony. Under such culture conditions, yeast colonies grow vertically and only at the locations where nutrients are delivered. Colonies increase in height at a steady growth rate that is inversely proportional to the cylinder radius. We show that the vertical growth rate of cylindrical colonies is not defined by the single-cell division rate, but rather by the colony metabolic yield. This contrasts with cells in liquid culture, in which the single-cell division rate is the only parameter that defines the population growth rate. This method also provides a direct, simple method to estimate the metabolic yield of a colony. Our study further demonstrates the importance of the shape of colonies on setting their expansion. We anticipate that our approach will be a starting point for elaborate studies of the population dynamics, evolution, and ecology of microbial colonies in complex landscapes. PMID:24853750

  13. Growing Yeast into Cylindrical Colonies

    PubMed Central

    Vulin, Clément; Di Meglio, Jean-Marc; Lindner, Ariel B.; Daerr, Adrian; Murray, Andrew; Hersen, Pascal

    2014-01-01

    Microorganisms often form complex multicellular assemblies such as biofilms and colonies. Understanding the interplay between assembly expansion, metabolic yield, and nutrient diffusion within a freely growing colony remains a challenge. Most available data on microorganisms are from planktonic cultures, due to the lack of experimental tools to control the growth of multicellular assemblies. Here, we propose a method to constrain the growth of yeast colonies into simple geometric shapes such as cylinders. To this end, we designed a simple, versatile culture system to control the location of nutrient delivery below a growing colony. Under such culture conditions, yeast colonies grow vertically and only at the locations where nutrients are delivered. Colonies increase in height at a steady growth rate that is inversely proportional to the cylinder radius. We show that the vertical growth rate of cylindrical colonies is not defined by the single-cell division rate, but rather by the colony metabolic yield. This contrasts with cells in liquid culture, in which the single-cell division rate is the only parameter that defines the population growth rate. This method also provides a direct, simple method to estimate the metabolic yield of a colony. Our study further demonstrates the importance of the shape of colonies on setting their expansion. We anticipate that our approach will be a starting point for elaborate studies of the population dynamics, evolution, and ecology of microbial colonies in complex landscapes. PMID:24853750

  14. Production of ethanol by immobilized yeast cells

    SciTech Connect

    Williams, D.; Munnecke, D.M.

    1981-08-01

    Saccharomyces cerevisiae cells were immobilized in calcium alginate beads for use in the continuous production of ethanol. Yeasts were grown in medium supplemented with ethanol to selectively screen for a culture which showed the greatest tolerance to ethanol inhibition. Yeast beads were produced from a yeast slurry containing 1.5% alginate (w/v) which was added as drops to a 0.05M CaCl2 solution. To determine their optimum fermentation parameters, ethanol production using glucose as a substrate was monitored in batch systems at varying physiological conditions (temperature,pH, ethanol concentration), cell densities, and gel concentrations. The data obtained were compared to optimum free cell ethanol fermentation parameters. The immobilized yeast cells were examined in a packed-bed reactor system operated under optimized parameters derived from batch-immobilized yeast cell experiments. Ethanol production rates, as well as residual sugar concentrations were monitored at different feedstock flow rates. (Refs. 13).

  15. Yeasts that utilize lactose in sweet whey

    SciTech Connect

    Gholson, J.H.; Gough, R.H.

    1980-01-01

    Since processing costs are usually higher for whey than for other available food or feed nutrients, only about one-third of whey produced in the US is used by food and feed industries. As a result whey disposal costs are a problem. Further; when whey is disposed of through municipal sewerage systems, the lactose present is changed by bacteria to lactic acid which tends to act as a preservative and retards further oxidation of whey constituents. This article describes a method of utilizing lactose-fermenting yeasts to produce large quantities of yeast cells, single-cell protein. Kluveromyces fragilis was found to be the most effective yeast species and the yeast cells produced could be used as a natural food or feed additive. Results of this study determined that certain methods and yeast strains could reduce whey-related pollution and thus help reduce costs of whey disposal.

  16. Yeast community survey in the Tagus estuary.

    PubMed

    de Almeida, João M G C F

    2005-07-01

    The yeast community in the waters of the Tagus estuary, Portugal, was followed for over a year in order to assess its dynamics. Yeast occurrence and incidence were measured and this information was related to relevant environmental data. Yeast occurrence did not seem to depend upon tides, but river discharge had a dramatic impact both on the density and diversity of the community. The occurrence of some yeasts was partially correlated with faecal pollution indicators. Yeast isolates were characterized by microsatellite primed PCR (MSP-PCR) fingerprinting and rRNA gene sequencing. The principal species found were Candida catenulata, C. intermedia, C. parapsilosis, Clavispora lusitaniae, Debaryomyces hansenii, Pichia guilliermondii, Rhodotorula mucilaginosa and Rhodosporidium diobovatum. The incidence of these species was evaluated against the environmental context of the samples and the current knowledge about the substrates from which they are usually isolated. PMID:16329949

  17. Yeasts and yeast-like fungi associated with tree bark: diversity and identification of yeasts producing extracellular endoxylanases.

    PubMed

    Bhadra, Bhaskar; Rao, R Sreenivas; Singh, Pavan K; Sarkar, Partha K; Shivaji, Sisinthy

    2008-05-01

    A total of 239 yeast strains was isolated from 52 tree bark samples of the Medaram and Srisailam forest areas of Andhra Pradesh, India. Based on analysis of D1/D2 domain sequence of 26S rRNA gene, 114 strains were identified as ascomycetous; 107 strains were identified as basidiomycetous yeasts; and 18 strains were identified as yeast-like fungi. Among the ascomycetous yeasts, 51% were identified as members of the genus Pichia, and the remaining 49% included species belonging to the genera Clavispora, Debaryomyces, Kluyveromyces, Hanseniaspora, Issatchenkia, Lodderomyces, Kodamaea, Metschnikowia, and Torulaspora. The predominant genera in the basidiomycetous yeasts were Cryptococcus (48.6%), Rhodotorula (29%), and Rhodosporidium (12.1%). The yeast-like fungi were represented by Aureobasidium pullulans (6.7%) and Lecythophora hoffmanii (0.8%). Of the 239 yeast strains tested for Xylanase, only five strains of Aureobasidium sp. produced xylanase on xylan-agar medium. Matrix-assisted laser desorption ionization-time of flight analysis and N-terminal amino-acid sequence of the xylanase of isolate YS67 showed high similarity with endo-1-4-beta-xylanase (EC 3.2.1.8) of Aureobasidium pullulans var. melanigenum. PMID:18219522

  18. Redescription of Argizala brasiliensis Walker, 1869 (Orthoptera: Grylloidea: Trigonidiidae: Nemobiinae: Pteronemobiini) and consideration of its morphological proximity to other Pteronemobiini Nearctic genera.

    PubMed

    Pereira, Marcelo Ribeiro; Martins, Luciano De P; Fernandes, Maria Luiza; Zefa, Edison; Sperber, Carlos Frankl

    2015-01-01

    Although male crickets provide more informative characters for the delimitation of species and genera, many taxonomic descriptions are based only on females. This is the case for Argizala Walker, 1869 and its two valid species, A. brasiliensis Walker, 1869 and A. hebardi Rehn, 1915. We provide herein a redescription of A. brasiliensis based on a male collected in the Pampa Biome, Capão do Leão municipality, Rio Grande do Sul State, Brazil. We present photographs of epitype and male genitalia, and discuss the diagnostic features of the genus and its morphological proximity to other Pteronemobiini Nearctic genera. PMID:26249883

  19. De Novo Assembly and Transcriptome Analysis of the Rubber Tree (Hevea brasiliensis) and SNP Markers Development for Rubber Biosynthesis Pathways

    PubMed Central

    Mantello, Camila Campos; Cardoso-Silva, Claudio Benicio; da Silva, Carla Cristina; de Souza, Livia Moura; Scaloppi Junior, Erivaldo José; de Souza Gonçalves, Paulo; Vicentini, Renato; de Souza, Anete Pereira

    2014-01-01

    Hevea brasiliensis (Willd. Ex Adr. Juss.) Muell.-Arg. is the primary source of natural rubber that is native to the Amazon rainforest. The singular properties of natural rubber make it superior to and competitive with synthetic rubber for use in several applications. Here, we performed RNA sequencing (RNA-seq) of H. brasiliensis bark on the Illumina GAIIx platform, which generated 179,326,804 raw reads on the Illumina GAIIx platform. A total of 50,384 contigs that were over 400 bp in size were obtained and subjected to further analyses. A similarity search against the non-redundant (nr) protein database returned 32,018 (63%) positive BLASTx hits. The transcriptome analysis was annotated using the clusters of orthologous groups (COG), gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Pfam databases. A search for putative molecular marker was performed to identify simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs). In total, 17,927 SSRs and 404,114 SNPs were detected. Finally, we selected sequences that were identified as belonging to the mevalonate (MVA) and 2-C-methyl-D-erythritol 4-phosphate (MEP) pathways, which are involved in rubber biosynthesis, to validate the SNP markers. A total of 78 SNPs were validated in 36 genotypes of H. brasiliensis. This new dataset represents a powerful information source for rubber tree bark genes and will be an important tool for the development of microsatellites and SNP markers for use in future genetic analyses such as genetic linkage mapping, quantitative trait loci identification, investigations of linkage disequilibrium and marker-assisted selection. PMID:25048025

  20. Isolation and structure elucidaton of polyphenols from Loranthus micranthus Linn. parasitic on Hevea brasiliensis with antiinflammatory property

    PubMed Central

    Agbo, Matthias Onyebuchi; Nworu, Chukwuemeka Sylvester; Okoye, Festus Basden Chied; Osadebe, Patience Ogoamaka

    2014-01-01

    The present study was carried out to evaluate the anti-inflammatory activities of polyphenols isolated from the leaves of mistletoe (Loranthus micranthus Linn.) parasitic on Hevea brasiliensis. The anti-inflammatory properties of the isolated compounds were evaluated on the basis of their ability to inhibit the production of nitric oxide (NO) and tumuor necrosis factor-? (TNF-?) in lipopolysaccharide (LPS) activated RAW 264.7 mouse macrophages. Semi-preparative HPLC separation of the ethyl acetate (EtOAc) and butanol (n-BuOH) fractions of the leaves of mistletoe (Loranthus micranthus Linn) parasitic on Hevea brasiliensis led to the isolation of four polyphenols: 3-O-(3,4,5-trimethoxybenzoyl)-(-)-epicatechin (TMECG) (1); (-)-epicatechin-3-O-(3?-O-methyl)-gallate (ECG3?Me) (2); rutin (3) and peltatoside (4). Compounds 1-4 were isolated for the first time from this plant while 1 was isolated for the first time in nature. These compounds (1-4) were readily identified by comparison of their spectroscopic data with those reported in the literature. The polyphenols proved to have anti-inflammatory activity as evidenced by the suppression of inducible nitric oxide (iNO) and cytokine (TNF-?) levels in the culture supernatant of lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophages. However, the study showed that the quercetin diglycosides showed stronger inhibition of proinflammatory mediators than the epicatechin derivates. These data provide evidence that polyphenolic compounds isolated from the mistletoe parasitic on Hevea brasiliensis may contribute to its anti-inflammatory properties by inhibiting the expression of inducible nitric oxide and proinflammatory cytokines such as tumour necrosis factor-?. PMID:26417309

  1. Alterations in hexose, amino acid and peptide transporter expression in intestinal epithelial cells during Nippostrongylus brasiliensis infection in the rat.

    PubMed

    Sekikawa, Shyuji; Kawai, Yuichi; Fujiwara, Atsushi; Takeda, Kazutoshi; Tegoshi, Tatsuya; Uchikawa, Ryuichi; Yamada, Minoru; Arizono, Naoki

    2003-10-01

    Infection with the nematode Nippostrongylus brasiliensis induces various types of cytological alterations in the intestinal villus epithelium. The aim of this study was to analyse the expression of hexose, peptide and amino acid transporters in the small intestinal epithelium after infection. Brown-Norway rats were infected with 2000 N. brasiliensis L3 larvae and villus epithelial cells were isolated at various time points after infection. Expression of hexose transporters Na(+)/glucose cotransporter SGLT1 and glucose transporter GLUT-1, -2 and -5, a peptide transporter (PepT1) and an amino acid transporter (LAT2) was examined by reverse transcription-PCR, Western blotting or immunohistochemistry. Semi-quantitative reverse transcription-PCR studies of separated jejunal epithelial cells showed that expression levels of GLUT5, PepT1 and LAT2 were significantly decreased 7 and 14 days after infection, while these changes were not observed in the ileal epithelium. Although the apical surface glucose transporter SGLT1 showed no significant alteration in mRNA expression, Western blotting analyses of jejunal epithelial cell lysate showed a marked decrease. Contrary to SGLT1, GLUT5, PepT1 and LAT2, expression of GLUT1, which is essential in maintaining high rates of glucose influx, was significantly up-regulated in the jejunal epithelium 7 and 14 days after infection in reverse transcription-PCR as in Western blotting analyses. Immunohistochemical studies showed that GLUT1 immunoreactivity was localised to the basolateral membrane of intestinal epithelial cells 7 days after infection. These results show that N. brasiliensis infection results in an increase in GLUT1 and a decrease in various hexose, amino acid and peptide transporter expression in jejunal epithelial cells. Up-regulation of GLUT1 might be a compensatory response in injured epithelial cells. PMID:14527524

  2. The acute-phase protein response in parasite infection. Nippostrongylus brasiliensis and Trichinella spiralis in the rat.

    PubMed Central

    Stadnyk, A W; Baumann, H; Gauldie, J

    1990-01-01

    During acute inflammation, the mammalian liver responds with increased production and secretion of a series of plasma glycoproteins, collectively termed the acute-phase proteins, resulting from the release at the site of inflammation of polypeptide cytokines, including IL-1 and IL-6, which interact with receptors on hepatocytes and alter gene expression. This attribute of the systemic acute-phase response was studied throughout the course of infection with two nematode parasites in rats. Significant increases in serum haptoglobin, alpha 1-acid glycoprotein and alpha 1-cysteine protease inhibitor were detected coincident with episodes of skin, lung and intestinal pathology during Nippostrongylus brasiliensis, but were not seen during Trichinella spiralis, infection of the rat despite similar intestinal pathology. These changes were seen at both the protein and mRNA levels in the liver. Infection with T. spiralis was not anti-inflammatory, as macrophages from various sites could be induced in vitro to release inflammatory cytokines, and in vivo induction of inflammation by turpentine injection was similar in control and infected animals. However, macrophage populations recovered from animals infected with T. spiralis were not activated. Moreover, intestinal infection alone with intestinal stages of N. brasiliensis also failed to elicit the systemic acute-phase protein response, requiring an explanation involving skin and lung for the acute-phase response during gut inflammation in a primary infection with N. brasiliensis. Taken together, these data suggest that during the intestinal phase of nematode infection, with pathological changes to the gut, the systemic acute-phase response is not elicited through compromise or lack of stimulation of inflammatory cells in the intestine. The systemic parameters of the acute-phase response may not be a component of gastrointestinal pathology. Images Figure 3 Figure 4 PMID:1692304

  3. Spatial analysis of egg distribution and geographic changes in the spawning habitat of the Brazilian sardine Sardinella brasiliensis.

    PubMed

    Gigliotti, E S; Gherardi, D F M; Paes, E T; Souza, R B; Katsuragawa, M

    2010-12-01

    This paper establishes the spawning habitat of the Brazilian sardine Sardinella brasiliensis and investigates the spatial variability of egg density and its relation with oceanographic conditions in the shelf of the south-east Brazil Bight (SBB). The spawning habitats of S. brasiliensis have been defined in terms of spatial models of egg density, temperature-salinity plots, quotient (Q) analysis and remote sensing data. Quotient curves (Q(C)) were constructed using the geographic distribution of egg density, temperature and salinity from samples collected during nine survey cruises between 1976 and 1993. The interannual sea surface temperature (SST) variability was determined using principal component analysis on the SST anomalies (SSTA) estimated from remote sensing data over the period between 1985 and 2007. The spatial pattern of egg occurrences in the SBB indicated that the largest concentration occurred between Paranaguá and São Sebastião. Spawning habitat expanded and contracted during the years, fluctuating around Paranaguá. In January 1978 and January 1993, eggs were found nearly everywhere along the inner shelf of the SBB, while in January 1988 and 1991 spawning had contracted to their southernmost position. The SSTA maps for the spawning periods showed that in the case of habitat expansion (1993 only) anomalies over the SBB were zero or slightly negative, whereas for the contraction period anomalies were all positive. Sardinella brasiliensis is capable of exploring suitable spawning sites provided by the entrainment of the colder and less-saline South Atlantic Central Water onto the shelf by means of both coastal wind-driven (to the north-east of the SBB) and meander-induced (to the south-west of the SBB) upwelling. PMID:21155781

  4. De novo assembly and transcriptome analysis of the rubber tree (Hevea brasiliensis) and SNP markers development for rubber biosynthesis pathways.

    PubMed

    Mantello, Camila Campos; Cardoso-Silva, Claudio Benicio; da Silva, Carla Cristina; de Souza, Livia Moura; Scaloppi Junior, Erivaldo José; de Souza Gonçalves, Paulo; Vicentini, Renato; de Souza, Anete Pereira

    2014-01-01

    Hevea brasiliensis (Willd. Ex Adr. Juss.) Muell.-Arg. is the primary source of natural rubber that is native to the Amazon rainforest. The singular properties of natural rubber make it superior to and competitive with synthetic rubber for use in several applications. Here, we performed RNA sequencing (RNA-seq) of H. brasiliensis bark on the Illumina GAIIx platform, which generated 179,326,804 raw reads on the Illumina GAIIx platform. A total of 50,384 contigs that were over 400 bp in size were obtained and subjected to further analyses. A similarity search against the non-redundant (nr) protein database returned 32,018 (63%) positive BLASTx hits. The transcriptome analysis was annotated using the clusters of orthologous groups (COG), gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Pfam databases. A search for putative molecular marker was performed to identify simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs). In total, 17,927 SSRs and 404,114 SNPs were detected. Finally, we selected sequences that were identified as belonging to the mevalonate (MVA) and 2-C-methyl-D-erythritol 4-phosphate (MEP) pathways, which are involved in rubber biosynthesis, to validate the SNP markers. A total of 78 SNPs were validated in 36 genotypes of H. brasiliensis. This new dataset represents a powerful information source for rubber tree bark genes and will be an important tool for the development of microsatellites and SNP markers for use in future genetic analyses such as genetic linkage mapping, quantitative trait loci identification, investigations of linkage disequilibrium and marker-assisted selection. PMID:25048025

  5. The wine and beer yeast Dekkera bruxellensis.

    PubMed

    Schifferdecker, Anna Judith; Dashko, Sofia; Ishchuk, Olena P; Piškur, Jure

    2014-09-01

    Recently, the non-conventional yeast Dekkera bruxellensis has been gaining more and more attention in the food industry and academic research. This yeast species is a distant relative of Saccharomyces cerevisiae and is especially known for two important characteristics: on the one hand, it is considered to be one of the main spoilage organisms in the wine and bioethanol industry; on the other hand, it is 'indispensable' as a contributor to the flavour profile of Belgium lambic and gueuze beers. Additionally, it adds to the characteristic aromatic properties of some red wines. Recently this yeast has also become a model for the study of yeast evolution. In this review we focus on the recently developed molecular and genetic tools, such as complete genome sequencing and transformation, to study and manipulate this yeast. We also focus on the areas that are particularly well explored in this yeast, such as the synthesis of off-flavours, yeast detection methods, carbon metabolism and evolutionary history. PMID:24932634

  6. Accelerating Yeast Prion Biology using Droplet Microfluidics

    NASA Astrophysics Data System (ADS)

    Ung, Lloyd; Rotem, Assaf; Jarosz, Daniel; Datta, Manoshi; Lindquist, Susan; Weitz, David

    2012-02-01

    Prions are infectious proteins in a misfolded form, that can induce normal proteins to take the misfolded state. Yeast prions are relevant, as a model of human prion diseases, and interesting from an evolutionary standpoint. Prions may also be a form of epigenetic inheritance, which allow yeast to adapt to stressful conditions at rates exceeding those of random mutations and propagate that adaptation to their offspring. Encapsulation of yeast in droplet microfluidic devices enables high-throughput measurements with single cell resolution, which would not be feasible using bulk methods. Millions of populations of yeast can be screened to obtain reliable measurements of prion induction and loss rates. The population dynamics of clonal yeast, when a fraction of the cells are prion expressing, can be elucidated. Furthermore, the mechanism by which certain strains of bacteria induce yeast to express prions in the wild can be deduced. Integrating the disparate fields of prion biology and droplet microfluidics reveals a more complete picture of how prions may be more than just diseases and play a functional role in yeast.

  7. Genomics and the making of yeast biodiversity.

    PubMed

    Hittinger, Chris Todd; Rokas, Antonis; Bai, Feng-Yan; Boekhout, Teun; Gonçalves, Paula; Jeffries, Thomas W; Kominek, Jacek; Lachance, Marc-André; Libkind, Diego; Rosa, Carlos A; Sampaio, José Paulo; Kurtzman, Cletus P

    2015-12-01

    Yeasts are unicellular fungi that do not form fruiting bodies. Although the yeast lifestyle has evolved multiple times, most known species belong to the subphylum Saccharomycotina (syn. Hemiascomycota, hereafter yeasts). This diverse group includes the premier eukaryotic model system, Saccharomyces cerevisiae; the common human commensal and opportunistic pathogen, Candida albicans; and over 1000 other known species (with more continuing to be discovered). Yeasts are found in every biome and continent and are more genetically diverse than angiosperms or chordates. Ease of culture, simple life cycles, and small genomes (∼10-20Mbp) have made yeasts exceptional models for molecular genetics, biotechnology, and evolutionary genomics. Here we discuss recent developments in understanding the genomic underpinnings of the making of yeast biodiversity, comparing and contrasting natural and human-associated evolutionary processes. Only a tiny fraction of yeast biodiversity and metabolic capabilities has been tapped by industry and science. Expanding the taxonomic breadth of deep genomic investigations will further illuminate how genome function evolves to encode their diverse metabolisms and ecologies. PMID:26649756

  8. Rheologically interesting polysaccharides from yeasts

    NASA Technical Reports Server (NTRS)

    Petersen, G. R.; Nelson, G. A.; Cathey, C. A.; Fuller, G. G.

    1989-01-01

    We have examined the relationships between primary, secondary, and tertiary structures of polysaccharides exhibiting the rheological property of friction (drag) reduction in turbulent flows. We found an example of an exopolysaccharide from the yeast Cryptococcus laurentii that possessed high molecular weight but exhibited lower than expected drag reducing activity. Earlier correlations by Hoyt showing that beta 1 --> 3, beta 2 --> 4, and alpha 1 --> 3 linkages in polysaccharides favored drag reduction were expanded to include correlations to secondary structure. The effect of sidechains in a series of gellan gums was shown to be related to sidechain length and position. Disruption of secondary structure in drag reducing polysaccharides reduced drag reducing activity for some but not all exopolysaccharides. The polymer from C. laurentii was shown to be more stable than xanthan gum and other exopolysaccharides under the most vigorous of denaturing conditions. We also showed a direct relationship between extensional viscosity measurements and the drag reducing coefficient for four exopolysaccharides.

  9. MAP kinase dynamics in yeast.

    PubMed

    van Drogen, F; Peter, M

    2001-09-01

    MAP kinase pathways play key roles in cellular responses towards extracellular signals. In several cases, the three core kinases interact with a scaffold molecule, but the function of these scaffolds is poorly understood. They have been proposed to contribute to signal specificity, signal amplification, or subcellular localization of MAP kinases. Several MAP kinases translocate to the nucleus in response to their activation, suggesting that nuclear transport may provide a regulatory mechanism. Here we describe new applications for Fluorescence Recovery After Photobleaching (FRAP) and Fluorescence Loss In Photobleaching (FLIP), to study dynamic translocations of MAPKs between different subcellular compartments. We have used these methods to measure the nuclear/cytoplasmic dynamics of several yeast MAP kinases, and in particular to address the role of scaffold proteins for MAP-kinase signaling. PMID:11730324

  10. Engineering alcohol tolerance in yeast

    PubMed Central

    Lam, Felix H.; Ghaderi, Adel; Fink, Gerald R.; Stephanopoulos, Gregory

    2015-01-01

    Ethanol toxicity in yeast Saccharomyces cerevisiae limits titer and productivity in the industrial production of transportation bioethanol. We show that strengthening the opposing potassium and proton electrochemical membrane gradients is a mechanism that enhances general resistance to multiple alcohols. Elevation of extracellular potassium and pH physically bolster these gradients, increasing tolerance to higher alcohols and ethanol fermentation in commercial and laboratory strains (including a xylose-fermenting strain) under industrial-like conditions. Production per cell remains largely unchanged with improvements deriving from heightened population viability. Likewise, up-regulation of the potassium and proton pumps in the laboratory strain enhances performance to levels exceeding industrial strains. Although genetically complex, alcohol tolerance can thus be dominated by a single cellular process, one controlled by a major physicochemical component but amenable to biological augmentation. PMID:25278607

  11. Extracellular Deoxyribonuclease Production by Yeasts

    PubMed Central

    Cazin, John; Kozel, Thomas R.; Lupan, David M.; Burt, Wayne R.

    1969-01-01

    A total of 20 genera of yeasts and yeastlike organisms were tested for their ability to produce an extracellular deoxyribonuclease. Results indicate that ability to produce the enzyme appears to be a specific characteristic of the three genera Rhodotorula, Cryptococcus, and Tremella. A single strain of Endomycopsis fibuligera was also shown to be positive for the enzyme. In comparing the ability of the organisms to excrete extracellular deoxyribonuclease with their ability to produce urease, a surprisingly close correlation was found. With the exception of Lipomyces starkeyi, all the organisms which were deoxyribonuclease-negative were also urease-negative. Of those organisms which were deoxyribonuclease-positive, only E. fibuligera was urease-negative. The ability of cryptococci to produce extracellular deoxyribonuclease is discussed in relation to the implication which this finding may have for the taxonomy and phylogeny of the genus. PMID:5354946

  12. Ethylene Response Factors Are Controlled by Multiple Harvesting Stresses in Hevea brasiliensis.

    PubMed

    Putranto, Riza-Arief; Duan, Cuifang; Kuswanhadi; Chaidamsari, Tetty; Rio, Maryannick; Piyatrakul, Piyanuch; Herlinawati, Eva; Pirrello, Julien; Dessailly, Florence; Leclercq, Julie; Bonnot, François; Tang, Chaorong; Hu, Songnian; Montoro, Pascal

    2015-01-01

    Tolerance of recurrent mechanical wounding and exogenous ethylene is a feature of the rubber tree. Latex harvesting involves tapping of the tree bark and ethephon is applied to increase latex flow. Ethylene is an essential element in controlling latex production. The ethylene signalling pathway leads to the activation of Ethylene Response Factor (ERF) transcription factors. This family has been identified in Hevea brasiliensis. This study set out to understand the regulation of ERF genes during latex harvesting in relation to abiotic stress and hormonal treatments. Analyses of the relative transcript abundance were carried out for 35 HbERF genes in latex, in bark from mature trees and in leaves from juvenile plants under multiple abiotic stresses. Twenty-one HbERF genes were regulated by harvesting stress in laticifers, revealing an overrepresentation of genes in group IX. Transcripts of three HbERF-IX genes from HbERF-IXc4, HbERF-IXc5 and HbERF-IXc6 were dramatically accumulated by combining wounding, methyl jasmonate and ethylene treatments. When an ethylene inhibitor was used, the transcript accumulation for these three genes was halted, showing ethylene-dependent induction. Subcellular localization and transactivation experiments confirmed that several members of HbERF-IX are activator-type transcription factors. This study suggested that latex harvesting induces mechanisms developed for the response to abiotic stress. These mechanisms probably depend on various hormonal signalling pathways. Several members of HbERF-IX could be essential integrators of complex hormonal signalling pathways in Hevea. PMID:25906196

  13. Physiological and Molecular Responses to Variation of Light Intensity in Rubber Tree (Hevea brasiliensis Muell. Arg.)

    PubMed Central

    Wang, Li-feng

    2014-01-01

    Light is one of most important factors to plants because it is necessary for photosynthesis. In this study, physiological and gene expression analyses under different light intensities were performed in the seedlings of rubber tree (Hevea brasiliensis) clone GT1. When light intensity increased from 20 to 1000 µmol m?2 s?1, there was no effect on the maximal quantum yield of photosystem II (PSII) photochemistry (Fv/Fm), indicating that high light intensity did not damage the structure and function of PSII reaction center. However, the effective photochemical quantum yield of PSII (Y(II)), photochemical quenching coefficient (qP), electron transfer rate (ETR), and coefficient of photochemical fluorescence quenching assuming interconnected PSII antennae (qL) were increased significantly as the light intensity increased, reached a maximum at 200 µmol m?2 s?1, but decreased from 400 µmol m?2 s?1. These results suggested that the PSII photochemistry showed an optimum performance at 200 µmol m?2 s?1 light intensity. The chlorophyll content was increased along with the increase of light intensity when it was no more than 400 µmol m?2 s?1. Since increasing light intensity caused significant increase in H2O2 content and decreases in the per unit activity of antioxidant enzymes SOD and POD, but the malondialdehyde (MDA) content was preserved at a low level even under high light intensity of 1000 µmol m?2 s?1, suggesting that high light irradiation did not induce membrane lipid peroxidation in rubber tree. Moreover, expressions of antioxidant-related genes were significantly up-regulated with the increase of light intensity. They reached the maximum expression at 400 µmol m?2 s?1, but decreased at 1000 µmol m?2 s?1. In conclusion, rubber tree could endure strong light irradiation via a specific mechanism. Adaptation to high light intensity is a complex process by regulating antioxidant enzymes activities, chloroplast formation, and related genes expressions in rubber tree. PMID:24586839

  14. Molecular cloning and characterization of a Mlo gene in rubber tree (Hevea brasiliensis).

    PubMed

    Qin, Bi; Zheng, Fucong; Zhang, Yu

    2015-03-01

    Mlo gene encodes a plant-specific seven-transmembrane domain protein involved in a variety of cellular processes. In this study, a novel Mlo gene from rubber tree (Hevea brasiliensis), designated HbMlo1, was cloned by RT-PCR in rubber tree. The ORF of HbMlo1 was 1551bp in length, encoding a putative protein of 516 amino acids. HbMlo1 was a typical Mlo protein with seven-transmembrane domain. Sequence comparison between HbMlo1 and other Mlo proteins demonstrated that HbMlo1 shared the highest similarity with the Cucumis melo CmMlo1 and Arabidopsis thaliana AtMlo1 with 75.1% and 71.3% sequence identity, respectively. Phylogenetic analysis revealed that HbMlo1, CmMlo1, AtMlo1, AtMlo13, and AtMlo15 formed into the phylogenetic clade II with 100% bootstrap support value. HbMlo1 transcript exhibited tissue specificity, and it was preferentially expressed in leaf. Furthermore, the amount of HbMlo1 transcript was significantly induced by various phytohormones (including ethephon, methyl jasmonate, salicylic acid, abscisic acid, indole-3-acetic acid, and gibberellic acid), H2O2, and wounding treatments. Under drought stress, HbMlo1 exhibited a complex pattern of regulation. However, HbMlo1 expression did not significantly change during powdery mildew infection. These results suggested that HbMlo1 might play a role in phytohormone signaling and abiotic stress response processes in rubber tree. PMID:25506769

  15. Physiological and molecular responses to variation of light intensity in rubber Tree (Hevea brasiliensis Muell. Arg.).

    PubMed

    Wang, Li-feng

    2014-01-01

    Light is one of most important factors to plants because it is necessary for photosynthesis. In this study, physiological and gene expression analyses under different light intensities were performed in the seedlings of rubber tree (Hevea brasiliensis) clone GT1. When light intensity increased from 20 to 1000 µmol m(-2) s(-1), there was no effect on the maximal quantum yield of photosystem II (PSII) photochemistry (Fv/Fm), indicating that high light intensity did not damage the structure and function of PSII reaction center. However, the effective photochemical quantum yield of PSII (Y(II)), photochemical quenching coefficient (qP), electron transfer rate (ETR), and coefficient of photochemical fluorescence quenching assuming interconnected PSII antennae (qL) were increased significantly as the light intensity increased, reached a maximum at 200 µmol m(-2) s(-1), but decreased from 400 µmol m(-2) s(-1). These results suggested that the PSII photochemistry showed an optimum performance at 200 µmol m(-2) s(-1) light intensity. The chlorophyll content was increased along with the increase of light intensity when it was no more than 400 µmol m(-2) s(-1). Since increasing light intensity caused significant increase in H2O2 content and decreases in the per unit activity of antioxidant enzymes SOD and POD, but the malondialdehyde (MDA) content was preserved at a low level even under high light intensity of 1000 µmol m(-2) s(-1), suggesting that high light irradiation did not induce membrane lipid peroxidation in rubber tree. Moreover, expressions of antioxidant-related genes were significantly up-regulated with the increase of light intensity. They reached the maximum expression at 400 µmol m(-2) s(-1), but decreased at 1000 µmol m(-2) s(-1). In conclusion, rubber tree could endure strong light irradiation via a specific mechanism. Adaptation to high light intensity is a complex process by regulating antioxidant enzymes activities, chloroplast formation, and related genes expressions in rubber tree. PMID:24586839

  16. Genetic variation and migration in the Mexican free-tailed bat (Tadarida brasiliensis mexicana).

    PubMed

    Russell, A L; Medellín, R A; McCracken, G F

    2005-06-01

    Incomplete lineage sorting can genetically link populations long after they have diverged, and will exert a more powerful influence on larger populations. The effects of this stochastic process can easily be confounded with those of gene flow, potentially leading to inaccurate estimates of dispersal capabilities or erroneous designation of evolutionarily significant units (ESUs). We have used phylogenetic, population genetic, and coalescent methods to examine genetic structuring in large populations of a widely dispersing bat species and to test hypotheses concerning the influences of coalescent stochasticity vs. gene flow. The Mexican free-tailed bat, Tadarida brasiliensis mexicana, exhibits variation in both migratory tendency and route over its range. Observations of the species' migratory behaviour have led to the description of behaviourally and geographically defined migratory groups, with the prediction that these groups compose structured gene pools. Here, we used mtDNA sequence analyses coupled with existing information from allozyme, banding, and natural history studies to evaluate hypotheses regarding the relationship between migration and genetic structure. Analyses of molecular variance revealed no significant genetic structuring of behaviourally distinct migratory groups. Demographic analyses were consistent with population growth, although the timing of population expansion events differs between migratory and nonmigratory populations. Hypotheses concerning the role of gene flow vs. incomplete lineage sorting on these data are explored using coalescent simulations. Our study demonstrates the importance of accounting for coalescent stochasticity in formulating phylogeographical hypotheses, and indicates that analyses that do not take such processes into account can lead to false conclusions regarding a species' phylogeographical history. PMID:15910338

  17. Organochlorine insecticide residues in the free-tailed bat (Tadarida brasiliensis) at Bracken Cave, Texas

    USGS Publications Warehouse

    Clark, D.R., Jr.; Martin, C.O.; Swineford, D.M.

    1975-01-01

    Fifty-nine free-tailed bats (Tadarida brasiliensis mexicana ) were collected at Bracken Cave, Texas, and analyzed for organochlorine insecticides and polychlorinated biphenyls (PCBs). Residues of DDE in the brain were greater in 12 young collected from the floor than in 15 young taken from the ceiling, but food deprivation, not higher residues in the brain, apparently caused young to fall....Among 18 pregnant females, residues of DDE and DDT were highest in yearlings. The first lactation by yearlings caused their residue loads to drop sharply. Thereafter, increasing age was accompanied by increasing residues but amounts generally did not exceed those in yearlings.....Residue levels in embryos were a function both of levels in the female parent and degree of embryonic development. Residues accumulated rapidly in nursing young, and lactating females may excrete from 1.3 to 16.2 (mean = 4.3) micrograms of DDE in milk per day. Maximum individual residue loads may be attained toward the end of nursing, and mobilization of these residues during southward migration may subject Bracken Cave free-tails to maximum lifetime residues in the brain....Comparison of our data with residue data for the free-tail population at Eagle Creek Cave (Arizona) in 1970 produced the following conclusions: ( 1) residues of DDE appeared similar in pregnant females, embryos, lactating females, and fallen young for the two populations; (2) residues of DDT and dieldrin appeared greater in pregnant females at Bracken Cave; (3) DDE and DDT occurred at greater levels in guano samples from Bracken Cave. On this basis, the population decline observed at Eagle Creek Cave between 1963 and 1969 does not appear to be related to the residues observed in the 1970 samples taken from that cave.

  18. Identification of novel microRNAs in Hevea brasiliensis and computational prediction of their targets

    PubMed Central

    2012-01-01

    Background Plants respond to external stimuli through fine regulation of gene expression partially ensured by small RNAs. Of these, microRNAs (miRNAs) play a crucial role. They negatively regulate gene expression by targeting the cleavage or translational inhibition of target messenger RNAs (mRNAs). In Hevea brasiliensis, environmental and harvesting stresses are known to affect natural rubber production. This study set out to identify abiotic stress-related miRNAs in Hevea using next-generation sequencing and bioinformatic analysis. Results Deep sequencing of small RNAs was carried out on plantlets subjected to severe abiotic stress using the Solexa technique. By combining the LeARN pipeline, data from the Plant microRNA database (PMRD) and Hevea EST sequences, we identified 48 conserved miRNA families already characterized in other plant species, and 10 putatively novel miRNA families. The results showed the most abundant size for miRNAs to be 24 nucleotides, except for seven families. Several MIR genes produced both 20-22 nucleotides and 23-27 nucleotides. The two miRNA class sizes were detected for both conserved and putative novel miRNA families, suggesting their functional duality. The EST databases were scanned with conserved and novel miRNA sequences. MiRNA targets were computationally predicted and analysed. The predicted targets involved in "responses to stimuli" and to "antioxidant" and "transcription activities" are presented. Conclusions Deep sequencing of small RNAs combined with transcriptomic data is a powerful tool for identifying conserved and novel miRNAs when the complete genome is not yet available. Our study provided additional information for evolutionary studies and revealed potentially specific regulation of the control of redox status in Hevea. PMID:22330773

  19. The suppression of rejection of Nippostrongylus brasiliensis in lactating rats: the nature of the immunological defect

    PubMed Central

    Dineen, J. K.; Kelly, J. D.

    1972-01-01

    Lactating female rats infected with 3000 third-stage larvae of Nippostrongylus brasiliensis showed significant increases in worm fecundity and total worm burdens when compared with infected nulliparous controls. Statistically significant differences were recorded for each of the three periods of infection, although these differences were of greatest magnitude during Period 3 (16–30 days of infection). Immune mesenteric lymph node cells (100 × 106), obtained from nulliparous female donors on Day 15 of a primary infection, were transferred syngeneically to lactating female recipients. The transferred cells invariably caused suppression of worm fecundity, reduction in the number of eggs per uterus in gravid female worms and rejection of a substantial proportion of worms by Day 10 of a challenge infection in the lactating recipients. The results of this study showed that immune cells were functional in lactating female recipients and that transfer of immune cells repaired the deficit in the rejection mechanism. Mesenteric lymph node cells (100 × 106), obtained from lactating female donors on Day 15 of a primary infection, were transferred syngeneically to nulliparous female recipients. The transferred cells caused suppression of worm fecundity, reduction in the number of eggs per uterus in gravid female worms and rejection of the majority of parasites by Day 10 of a challenge infection in the nulliparous recipients. Clearly, potentially immune lymphoid cells were present in the mesenteric nodes of lactating females at the time that the rejection mechanism was severely impaired. Mesenteric lymph node cells obtained from infected lactating donors were substantially less effective in lactating recipients than in nulliparous recipients. These cells caused the expulsion of 51 per cent of worms by Day 10 in lactating recipients, whereas they caused expulsion of 99 per cent of worms in nulliparous recipients. These observations suggest that the inductive processes of the immune response occur normally, but that differentiation of induced cells to effector cells is impaired in lactating animals. PMID:5062546

  20. Identification of the Hevea brasiliensis AP2/ERF superfamily by RNA sequencing

    PubMed Central

    2013-01-01

    Background Rubber tree (Hevea brasiliensis) laticifers are the source of natural rubber. Rubber production depends on endogenous and exogenous ethylene (ethephon). AP2/ERF transcription factors, and especially Ethylene-Response Factors, play a crucial role in plant development and response to biotic and abiotic stresses. This study set out to sequence transcript expressed in various tissues using next-generation sequencing and to identify AP2/ERF superfamily in the rubber tree. Results The 454 sequencing technique was used to produce five tissue-type transcript libraries (leaf, bark, latex, embryogenic tissues and root). Reads from all libraries were pooled and reassembled to improve mRNA lengths and produce a global library. One hundred and seventy-three AP2/ERF contigs were identified by in silico analysis based on the amino acid sequence of the conserved AP2 domain from the global library. The 142 contigs with the full AP2 domain were classified into three main families (20 AP2 members, 115 ERF members divided into 11 groups, and 4 RAV members) and 3 soloist members. Fifty-nine AP2/ERF transcripts were found in latex. Alongside the microRNA172 already described in plants, eleven additional microRNAs were predicted to inhibit Hevea AP2/ERF transcripts. Conclusions Hevea has a similar number of AP2/ERF genes to that of other dicot species. We adapted the alignment and classification methods to data from next-generation sequencing techniques to provide reliable information. We observed several specific features for the ERF family. Three HbSoloist members form a group in Hevea. Several AP2/ERF genes highly expressed in latex suggest they have a specific function in Hevea. The analysis of AP2/ERF transcripts in Hevea presented here provides the basis for studying the molecular regulation of latex production in response to abiotic stresses and latex cell differentiation. PMID:23324139

  1. The Latex of Hevea brasiliensis Contains High Levels of Both Chitinases and Chitinases/Lysozymes 1

    PubMed Central

    Martin, Melinda N.

    1991-01-01

    The latex of the commercial rubber tree, Hevea brasiliensis, was fractionated by ultracentrifugation as described by G. F. J. Moir ([1959] Nature 184: 1626-1628) into a top layer of rubber particles, a cleared cytoplasm, and a pellet that contains primarily specialized vacuoles known as lutoids. The proteins in each fraction were resolved by two-dimensional gel electrophoresis. Both the pellet fraction and cleared cytoplasm contained large amounts of relatively few proteins, suggesting that laticifers serve a very specialized function in the plant. More than 75% of the total soluble protein in latex was found in the pellet fraction. Twenty-five percent of the protein in the pellet was identified as chitinases/lysozymes, which are capable of degrading the chitin component of fungal cell walls and the peptidoglycan component of bacterial cell walls. Both the chitinase and lysozyme activities were localized exclusively in the pellet or lutoid fraction. The chitinases/lysozymes were resolved into acidic and basic classes of proteins and further purified. An acidic protein (molecular mass 25.5 kD) represented 20% of the chitinase activity in latex; this protein lacked the low level of lysozyme activity that is associated with many plant chitinases. Six basic proteins, having both chitinase and lysozyme activities in various ratios and molecular mass of 27.5 or 26 kD, were resolved. Two of the basic proteins had very high lysozyme specific activities which were comparable to the specific activities reported for animal lysozymes. Like animal lysozymes, but unlike previously characterized plant chitinases/lysozymes, these basic chitinases/lysozymes were also capable of completely lysing or clearing suspensions of bacterial cell walls. These results suggest that laticifers may serve a defensive role in the plant. Images Figure 2 Figure 5 PMID:16668007

  2. Catalytic mechanism of hydroxynitrile lyase from Hevea brasiliensis: a theoretical investigation.

    PubMed

    Cui, Feng-Chao; Pan, Xiao-Liang; Liu, Jing-Yao

    2010-07-29

    Density functional theory (DFT) calculations using the hybrid functional B3LYP have been performed to investigate the catalytic mechanism of hydroxynitrile lyase from Hevea brasiliensis (Hb-HNL). This enzyme catalyzes the cleavage of acetone cyanohydrin to hydrocyanic acid plus acetone. Two models (A and B) of the active site consisting of 105 and 155 atoms, respectively, were constructed on the basis of the crystal structure. Good consistency between the two models provides a verification of the proposed mechanism. Our calculations show that the catalytic reaction proceeds via three elementary steps: (1) deprotonation of the OH-Ser80 by His235 and concomitant abstraction of a proton from the substrate hydroxyl by Ser80; (2) the C-C bond cleavage of the acetone cyanohydrin; and (3) protonation of the cleaved cyanide by His235. The cleavage of the C-C bond is the rate-limiting step with the overall free energy barrier of 13.5 kcal/mol for relatively smaller model A (14.9 kcal/mol for a larger model B) in the protein environment, which is in good agreement with experimental rate. The present results give support to the previously proposed general acid/base catalytic mechanism, in which the catalytic triad acts as a general acid/base. Moreover, the calculated results for model C, with the positive charge of Lys236 removed from model A, show that Lys236 with the positive charge plays a vital role in lowering the reaction barrier of the rate-determining and helps in stabilizing the negatively charged CN(-) by forming a hydrogen bond with the substrate, consistent with the experimental analysis. PMID:20593768

  3. Characterization and cytotoxic activity of sulfated derivatives of polysaccharides from Agaricus brasiliensis

    PubMed Central

    Cardozo, F. T. G. S.; Camelini, C. M.; Cordeiro, M. N. S.; Mascarello, A.; Malagoli, B. G.; Larsen, I.; Rossi, M. J.; Nunes, R. J.; Braga, F. C.; Brandt, C.R.; Simões, C. M. O.

    2014-01-01

    Agaricus brasiliensis cell-wall polysaccharides isolated from fruiting body (FR) and mycelium (MI) and their respective sulfated derivatives (FR-S and MI-S) were chemically characterized using elemental analysis, TLC, FT-IR, NMR, HPLC, and thermal analysis. Cytotoxic activity was evaluated against A549 tumor cells by MTT and sulforhodamine assays. The average molecular weight (Mw) of FR and MI was estimated to be 609 and 310 kDa, respectively. FR-S (127 kDa) and MI-S (86 kDa) had lower Mw, probably due to hydrolysis occurred during the sulfation reaction. FR-S and MI-S presented ~14 % sulfur content in elemental analysis. Sulfation of samples was characterized by the appearance of two new absorption bands at 1253 and 810 cm?1 in the infrared spectra, related to S=O and C-S-O sulfate groups, respectively. Through 1H and 13C NMR analysis FR-S was characterized as a (1?6)-(1?3)-?-D-glucan fully sulfated at C-4 and C-6 terminal and partially sulfated at C-6 of (1?3)-?-D-glucan moiety. MI-S was shown to be a (1?3)-?-D-gluco-(1?2)-?-D-mannan, partially sulfated at C-2, C-3, C-4, and C-6, and fully sulfated at C-6 of the terminal residues. The combination of high degree of sulfation and low molecular weight was correlated with the increased cytotoxic activity (48 h of treatment) of both FR-S (EC50=605.6 ?g/mL) and MI-S (EC50=342.1 ?g/mL) compared to the non-sulfated polysaccharides FR and MI (EC50>1500 ?g/mL). PMID:23511057

  4. Ethylene Response Factors Are Controlled by Multiple Harvesting Stresses in Hevea brasiliensis

    PubMed Central

    Putranto, Riza-Arief; Duan, Cuifang; Kuswanhadi; Chaidamsari, Tetty; Rio, Maryannick; Piyatrakul, Piyanuch; Herlinawati, Eva; Pirrello, Julien; Dessailly, Florence; Leclercq, Julie; Bonnot, François; Tang, Chaorong; Hu, Songnian; Montoro, Pascal

    2015-01-01

    Tolerance of recurrent mechanical wounding and exogenous ethylene is a feature of the rubber tree. Latex harvesting involves tapping of the tree bark and ethephon is applied to increase latex flow. Ethylene is an essential element in controlling latex production. The ethylene signalling pathway leads to the activation of Ethylene Response Factor (ERF) transcription factors. This family has been identified in Hevea brasiliensis. This study set out to understand the regulation of ERF genes during latex harvesting in relation to abiotic stress and hormonal treatments. Analyses of the relative transcript abundance were carried out for 35 HbERF genes in latex, in bark from mature trees and in leaves from juvenile plants under multiple abiotic stresses. Twenty-one HbERF genes were regulated by harvesting stress in laticifers, revealing an overrepresentation of genes in group IX. Transcripts of three HbERF-IX genes from HbERF-IXc4, HbERF-IXc5 and HbERF-IXc6 were dramatically accumulated by combining wounding, methyl jasmonate and ethylene treatments. When an ethylene inhibitor was used, the transcript accumulation for these three genes was halted, showing ethylene-dependent induction. Subcellular localization and transactivation experiments confirmed that several members of HbERF-IX are activator-type transcription factors. This study suggested that latex harvesting induces mechanisms developed for the response to abiotic stress. These mechanisms probably depend on various hormonal signalling pathways. Several members of HbERF-IX could be essential integrators of complex hormonal signalling pathways in Hevea. PMID:25906196

  5. Impact of age of rubber (Hevea brasiliensis) plantation on earthworm communities of West Tripura (India).

    PubMed

    Chaudhuri, P S; Bhattacharjee, Subhalaxmi; Dey, Animesh; Chattopadhyay, Sharmila; Bhattacharya, Dipto

    2013-01-01

    A comparative analysis of earthworm communities was carried out in the rubber plantations (Hevea brasiliensis) of different age groups in West Tripura to understand the impact of such exotic and monoculture plantation in biodiversity conservation. Earthworm communities were studied on monthly basis over a period of one year (2006-2007) in the 3, 10, 14, 20 and 25 year-old plantations. Among twelve earthworm species collected from the studied sites, six species belonged to Octochaetidae [Eutyphoeus assomensis Stephenson, Eutyphoeus comillahnus Michaelsen, Lennogaster chittagongensis (Stephensen), Octochaetona beatrix Gates, Dichogaster offinis Michaelsen, Lennogaster yeicus (Stephensen)], two species each to Megascolecidae [Metaphire houlleti (Perrier), Konchurio sp. 1] and Moniligastridae [Drowida nepalensis Michaelsen, Drawida papillifer papillifer Stephenson], one species each to Glossoscolecidae [Pontoscolex corethrurus (Muller)] and Ocnerodrilidae [Gordiodrilus elegans Beddard]. Exotic species P corethrurus, M. houlleti and native peregrine species like D. nepolensis and D. papillifer papillifer were distributed in all the age groups of plantation, while other species showed restricted distribution. P. corethrurus contributed more than 60% biomass and 70% density of earthworm communities in rubber plantation. With aging of rubber plantations both the densities and biomasses of earthworms increased. High contents of polyphenol, flavonoid and lignin in the litters of 3 and 10 year-old-rubber plantations through their effects on food intake, probably resulted to low biomass values of earthworms in those age groups of plantation. With further increase in the age of plantations beyond 10 years, polyphenol, flavonoid and lignin contents decreased. Accordingly the biomass of earthworms increased with increase in the age of plantation. Soil moisture increased with increase in the age of plantation and there was a good positive correlation between soil moisture and earthworm biomass (p < 0.01). Density, biomass and dominance of earthworms increased while species diversity, species richness and species evenness of earthworm community were decreased with increase in the age of rubber plantation. PMID:24006808

  6. 21 CFR 172.325 - Bakers yeast protein.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Bakers yeast protein. 172.325 Section 172.325 Food... Special Dietary and Nutritional Additives § 172.325 Bakers yeast protein. Bakers yeast protein may be safely used in food in accordance with the following conditions: (a) Bakers yeast protein is...

  7. 21 CFR 172.325 - Bakers yeast protein.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Bakers yeast protein. 172.325 Section 172.325 Food... Special Dietary and Nutritional Additives § 172.325 Bakers yeast protein. Bakers yeast protein may be safely used in food in accordance with the following conditions: (a) Bakers yeast protein is...

  8. Yeast cell-surface expression of chitosanase from Paenibacillus fukuinensis.

    PubMed

    Fukuda, Takeshi; Isogawa, Danya; Takagi, Madoka; Kato-Murai, Michiko; Kimoto, Hisashi; Kusaoke, Hideo; Ueda, Mitsuyoshi; Suye, Shin-Ichiro

    2007-11-01

    To produce chitoorigosaccharides using chitosan, we attempted to construct Paenibacillus fukuinensis chitosanase-displaying yeast cells as a whole-cell biocatalyst through yeast cell-surface engineering. The localization of the chitosanase on the yeast cell surface was confirmed by immunofluorescence labeling of cells. The chitosanase activity of the constructed yeast was investigated by halo assay and the dinitrosalicylic acid method. PMID:17986777

  9. 21 CFR 172.325 - Bakers yeast protein.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Bakers yeast protein. 172.325 Section 172.325 Food... Special Dietary and Nutritional Additives § 172.325 Bakers yeast protein. Bakers yeast protein may be safely used in food in accordance with the following conditions: (a) Bakers yeast protein is...

  10. 21 CFR 172.325 - Bakers yeast protein.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Bakers yeast protein. 172.325 Section 172.325 Food... Special Dietary and Nutritional Additives § 172.325 Bakers yeast protein. Bakers yeast protein may be safely used in food in accordance with the following conditions: (a) Bakers yeast protein is...

  11. 21 CFR 172.325 - Bakers yeast protein.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Bakers yeast protein. 172.325 Section 172.325 Food... Additives § 172.325 Bakers yeast protein. Bakers yeast protein may be safely used in food in accordance with the following conditions: (a) Bakers yeast protein is the insoluble proteinaceous material...

  12. Assembly of eukaryotic algal chromosomes in yeast

    PubMed Central

    2013-01-01

    Background Synthetic genomic approaches offer unique opportunities to use powerful yeast and Escherichia coli genetic systems to assemble and modify chromosome-sized molecules before returning the modified DNA to the target host. For example, the entire 1 Mb Mycoplasma mycoides chromosome can be stably maintained and manipulated in yeast before being transplanted back into recipient cells. We have previously demonstrated that cloning in yeast of large (> ~ 150 kb), high G + C (55%) prokaryotic DNA fragments was improved by addition of yeast replication origins every ~100 kb. Conversely, low G + C DNA is stable (up to at least 1.8 Mb) without adding supplemental yeast origins. It has not been previously tested whether addition of yeast replication origins similarly improves the yeast-based cloning of large (>150 kb) eukaryotic DNA with moderate G + C content. The model diatom Phaeodactylum tricornutum has an average G + C content of 48% and a 27.4 Mb genome sequence that has been assembled into chromosome-sized scaffolds making it an ideal test case for assembly and maintenance of eukaryotic chromosomes in yeast. Results We present a modified chromosome assembly technique in which eukaryotic chromosomes as large as ~500 kb can be assembled from cloned ~100 kb fragments. We used this technique to clone fragments spanning P. tricornutum chromosomes 25 and 26 and to assemble these fragments into single, chromosome-sized molecules. We found that addition of yeast replication origins improved the cloning, assembly, and maintenance of the large chromosomes in yeast. Furthermore, purification of the fragments to be assembled by electroelution greatly increased assembly efficiency. Conclusions Entire eukaryotic chromosomes can be successfully cloned, maintained, and manipulated in yeast. These results highlight the improvement in assembly and maintenance afforded by including yeast replication origins in eukaryotic DNA with moderate G + C content (48%). They also highlight the increased efficiency of assembly that can be achieved by purifying fragments before assembly. PMID:24325901

  13. Efforts to make and apply humanized yeast

    PubMed Central

    Laurent, Jon M.; Young, Jonathan H.; Kachroo, Aashiq H.

    2016-01-01

    Despite a billion years of divergent evolution, the baker’s yeast Saccharomyces cerevisiae has long proven to be an invaluable model organism for studying human biology. Given its tractability and ease of genetic manipulation, along with extensive genetic conservation with humans, it is perhaps no surprise that researchers have been able to expand its utility by expressing human proteins in yeast, or by humanizing specific yeast amino acids, proteins or even entire pathways. These methods are increasingly being scaled in throughput, further enabling the detailed investigation of human biology and disease-specific variations of human genes in a simplified model organism. PMID:26462863

  14. Evaluation of the Uni-Yeast-Tek kit for the identification of medically important yeasts.

    PubMed Central

    Bowman, P I; Ahearn, D G

    1975-01-01

    The Uni-Yeast-Tek system, a commercially prepared kit and scheme for the rapid identification of medically important yeasts (Corning Medical), was evaluated in comparison with a conventional procedure in the identification of 623 yeasts. The system permitted the presumptive identification of 99.8% of 436 isolates representing 16 common species commonly isolated in the clinical laboratory. Correct biochemical and morphological analyses were obtained with 48 other species, but their specific identification required additional data. Images PMID:1102563

  15. Identification of laticifer-specific genes and their promoter regions from a natural rubber producing plant Hevea brasiliensis.

    PubMed

    Aoki, Yuichi; Takahashi, Seiji; Takayama, Daisuke; Ogata, Yoshiyuki; Sakurai, Nozomu; Suzuki, Hideyuki; Asawatreratanakul, Kasem; Wititsuwannakul, Dhirayos; Wititsuwannakul, Rapepun; Shibata, Daisuke; Koyama, Tanetoshi; Nakayama, Toru

    2014-08-01

    Latex, the milky cytoplasm of highly differentiated cells called laticifers, from Hevea brasiliensis is a key source of commercial natural rubber production. One way to enhance natural rubber production would be to express genes involved in natural rubber biosynthesis by a laticifer-specific overexpression system. As a first step to identify promoters which could regulate the laticifer-specific expression, we identified random clones from a cDNA library of H. brasiliensis latex, resulting in 4325 expressed sequence tags (ESTs) assembled into 1308 unigenes (692 contigs and 617 singletons). Quantitative analyses of the transcription levels of high redundancy clones in the ESTs revealed genes highly and predominantly expressed in laticifers, such as Rubber Elongation Factor (REF), Small Rubber Particle Protein and putative protease inhibitor proteins. HRT1 and HRT2, cis-prenyltransferases involved in rubber biosynthesis, was also expressed predominantly in laticifers, although these transcript levels were 80-fold lower than that of REF. The 5'-upstream regions of these laticifer-specific genes were cloned and analyzed in silico, revealing seven common motifs consisting of eight bases. Furthermore, transcription factors specifically expressed in laticifers were also identified. The common motifs in the laticifer-specific genes and the laticifer-specific transcription factors are potentially involved in the regulation of gene expression in laticifers. PMID:25017153

  16. In situ TLR2 and TLR4 expression in a murine model of mycetoma caused by Nocardia brasiliensis.

    PubMed

    Millán-Chiu, Blanca Edith; Hernández-Hernández, Francisca; Pérez-Torres, Armando; Méndez-Tovar, Luis Javier; López-Martínez, Rubén

    2011-04-01

    Actinomycetoma caused by Nocardia brasiliensis is a common disease in tropical regions. This ailment is characterized by a localized chronic inflammation that mainly affects the lower limbs. Toll-like receptors (TLRs) recognize pathogen-associated molecular patterns, inducing the production of proinflammatory mediators. The role of TLRs in the immune response against N. brasiliensis is unknown. The aim of this work was to locate and quantify in a murine model the expression of TLR2 and TLR4 in the infection site using reverse transcription-PCR and immunohistochemistry. The results showed that TLR2 expression increased in the infected tissue, whereas TLR4 expression decreased. The presence of TLR2 and TLR4 was demonstrated in different cell populations throughout the chronic infectious process. In the early stages of this process, TLR2 was expressed in neutrophils and macrophages in direct contact with the inoculum, whereas TLR4 was observed in mast cells. In the advanced stages of the infection, TLR2 was expressed in foam cells and fibroblasts and was likely associated with bacterial containment, while TLR4 was downregulated, probably resulting in an imbalance between the host immune response and the bacterial load that favoured chronic disease. PMID:21205004

  17. Thermoregulation during flight: body temperature and sensible heat transfer in free-ranging Brazilian free-tailed bats (Tadarida brasiliensis).

    PubMed

    Reichard, Jonathan D; Fellows, Spenser R; Frank, Alexander J; Kunz, Thomas H

    2010-01-01

    Bat wings are important for thermoregulation, but their role in heat balance during flight is largely unknown. More than 80% of the energy consumed during flight generates heat as a by-product, and thus it is expected that bat wings should dissipate large amounts of heat to prevent hyperthermia. We measured rectal (T(r)) and surface (T(s)) temperatures of Brazilian free-tailed bats (Tadarida brasiliensis) as they emerged from and returned to their daytime roosts and calculated sensible heat transfer for different body regions (head, body, wings, and tail membrane). Bats' T(r) decreased from 36.8°C during emergence flights to 34.4°C during returns, and T(s) scaled positively with ambient temperature (T(a)). Total radiative heat loss from bats was significantly greater for a radiative sink to the night sky than for a sink with temperature equal to T(a). We found that free-ranging Brazilian free-tailed bats, on average, do not dissipate heat from their wings by convection but instead dissipate radiative heat (L) to the cloudless night sky during flight ([Formula: see text] W). However, within the range of T(a) measured in this study, T. brasiliensis experienced net heat loss between evening emergence and return flights. Regional hypothermia reduces heat loss from wings that are exposed to potentially high convective fluxes. Additional research is needed to establish the role of wings in evaporative cooling during flight in bats. PMID:21034204

  18. Dentary Morphological Variation in Clevosaurus brasiliensis (Rhynchocephalia, Clevosauridae) from the Upper Triassic of Rio Grande do Sul, Brazil

    PubMed Central

    Romo de Vivar Martínez, Paula Rosario; Bento Soares, Marina

    2015-01-01

    Clevosaurus was a cosmopolitan rhynchocephalian genus, known from the Late Triassic to the Early Jurassic. In South America this genus is represented by C. brasiliensis, an important component of the Linha São Luiz taphocoenosis, on the top of the Norian Santa Maria 2 Sequence of Southern Brazil. The best preserved and most abundant bone elements of C. brasiliensis are dentaries, in which variations of shape and size are observed. The aim of this study is to describe and evaluate the variation, using geometric morphometrics methods. Geometric morphometric analysis of 10 specimens highlights variations in relative size of the dentary. Most of the variation observed for PC1 (83.3%) is likely related to ontogeny, and PC2 (10.0%) is likely related to taphonomic signatures. The development patterns observed, such as the growth of the dentary, consists of differential growth in length between the posterior portion of the dentary, that grows at a higher rate, regarding the anterior portion of the element. This allometric growth is similar to what is observed in other rhynchocephalians and is accompanied by the allometric skull growth, similar to the trend exhibited by clevosaurs. The taphocoenosis is bimodal (juveniles and adults) with a bias towards adult preservation. Some diagenetic influence is reflected in deformed skulls and this is observed in the tangent-plot. Finally, a strong correlation was detected between the taphonomic signatures and the PC2, regarding specially disarticulation and degree of fragmentation. PMID:25793754

  19. Cysteine protease of the nematode Nippostrongylus brasiliensis preferentially evokes an IgE/IgG1 antibody response in rats.

    PubMed Central

    Kamata, I; Yamada, M; Uchikawa, R; Matsuda, S; Arizono, N

    1995-01-01

    Some cysteine proteases such as papain and those of mites and schistosomes have potent allergenic properties. To clarify the allergenicity of nematode cysteine proteases, the enzyme was purified from the intestinal nematode Nippostrongylus brasiliensis using cation exchange chromatography and gel filtration chromatography. The purified protease, of 16 kD and pI 8.5, showed maximum enzyme activity at pH 5.5 and substrate preference for Z-Phe-Arg-MCA. The specific inhibitors of cysteine protease leupeptin, iodoacetic acid, and E-64, completely suppressed the activity, indicating that the purified enzyme belongs to the cysteine protease family. Cysteine protease activity was found not only in somatic extract, but also in the excretory-secretory (ES) product of the nematode. When anti-cysteine protease immunoglobulin isotypes were examined in sera from rats infected with N. brasiliensis, a high level of IgG1 and a lower level of IgE antibody were detected. Depletion of IgG antibodies from the sera using protein G affinity columns resulted in a marked increase in reactivity of anti-cysteine protease IgE with the antigen, possibly due to the removal of competing IgG antibodies. In contrast to IgE and IgG1, production of anti-cysteine protease IgG2a was negligible. These results indicate that the nematode cysteine protease preferentially evokes an IgE/IgG1 antibody response. Images Fig. 2 PMID:7554403

  20. Nippostrongylus brasiliensis: Identification of Intelectin-1 and -2 as Stat6-dependent genes expressed in lung and intestine during infection

    PubMed Central

    Voehringer, David; Stanley, Sarah A.; Cox, Jeffery S.; Completo, Gladys C.; Lowary, Todd L.; Locksley, Richard M.

    2009-01-01

    Elimination of the helminth parasite Nippostrongylus brasiliensis from infected mice is mediated by IL-4 or IL-13 and dependent on the IL-4R? chain and the transcription factor Stat6 in non-hematopoietic cells. However, it is not clear which Stat6-dependent effector molecules mediate worm expulsion. We identified intelectin-1 and -2 as Stat6-dependent genes that are induced during infection. Intelectins can bind galactofuranose, a sugar present only in microorganisms and might therefore serve as microbial pattern element. To analyze whether constitutive expression of intelectin-1 or -2 leads to accelerated pathogen clearance, transgenic mice were generated which express high levels of these genes selectively in the lung. Infection with N. brasiliensis or Mycobacterium tuberculosis did not result in accelerated pathogen clearance in transgenic as compared to wild-type mice. Further, no significant modulation of the immune response in lung or lymph nodes was observed. Thus, under these conditions, intelectins did not enhance pathogen clearance. PMID:17420014

  1. Communication during copulation in the sex-role reversed wolf spider Allocosa brasiliensis: Female shakes for soliciting new ejaculations?

    PubMed

    Garcia Diaz, Virginia; Aisenberg, Anita; Peretti, Alfredo V

    2015-07-01

    Traditional studies on sexual communication have focused on the exchange of signals during courtship. However, communication between the sexes can also occur during or after copulation. Allocosa brasiliensis is a wolf spider that shows a reversal in typical sex roles and of the usual sexual size dimorphism expected for spiders. Females are smaller than males and they are the roving sex that initiates courtship. Occasional previous observations suggested that females performed body shaking behaviors during copulation. Our objective was to analyze if female body shaking is associated with male copulatory behavior in A. brasiliensis, and determine if this female behavior has a communicatory function in this species. For that purpose, we performed fine-scaled analysis of fifteen copulations under laboratory conditions. We video-recorded all the trials and looked for associations between female and male copulatory behaviors. The significant difference between the time before and after female shaking, in favor of the subsequent ejaculation is analyzed. We discuss if shaking could be acting as a signal to accelerate and motivate palpal insertion and ejaculation, and/or inhibiting male cannibalistic tendencies in this species. PMID:25963301

  2. Behavioural evidence of male volatile pheromones in the sex-role reversed wolf spiders Allocosa brasiliensis and Allocosa alticeps

    NASA Astrophysics Data System (ADS)

    Aisenberg, Anita; Baruffaldi, Luciana; González, Macarena

    2010-01-01

    The use of chemical signals in a sexual context is widespread in the animal kingdom. Most studies in spiders report the use of female pheromones that attract potential sexual partners. Allocosa brasiliensis and Allocosa alticeps are two burrowing wolf spiders that show sex-role reversal. Females locate male burrows and initiate courtship before males perform any detectable visual or vibratory signal. So, females of these species would be detecting chemical or mechanical cues left by males. Our objective was to explore the potential for male pheromones to play a role in mate detection in A. brasiliensis and A. alticeps. We designed two experiments. In Experiment 1, we tested the occurrence of male contact pheromones by evaluating female courtship when exposed to empty burrows constructed by males or females (control). In Experiment 2, we tested the existence of male volatile pheromones by evaluating female behaviour when exposed to artificial burrows connected to tubes containing males, females or empty tubes (control). Our results suggest the occurrence of male volatile pheromones that trigger female courtship in both Allocosa species. The sex-role reversal postulated for these wolf spiders could be driving the consequent reversal in typical pheromone-emitter and detector roles expected for spiders.

  3. Development of the Sea Star Echinaster (Othilia) brasiliensis, with Inference on the Evolution of Development and Skeletal Plates in Asteroidea.

    PubMed

    Lopes, Elinia Medeiros; Ventura, Carlos Renato Rezende

    2016-02-01

    We describe the development and juvenile morphology of the sea star Echinaster (Othilia) brasiliensis in order to explore evolutionary developmental modes and skeletal homologies. This species produces large, buoyant eggs (0.6 ± 0.03 mm diameter), and has a typical lecithotrophic brachiolaria larva. The planktonic brachiolaria larva is formed 2-4 days after fertilization, when cilia cover the surface. Early juveniles are completely formed by 18 days of age. Initial growth is supported by maternal nutrients while the stomach continues to develop until 60 days after fertilization, when juveniles reach about 0.5 mm of radius length. The madreporite was observed 88 days after fertilization. In the youngest juvenile skeleton of E. (O.) brasiliensis, the madreporite and odontophore are homologous to those of other recent, non-paxillosid asteroids, and follow the Late Madreporic Mode. The emergence of plates related to the ambulacral system follows the Ocular Plate Rule. The development and juvenile skeletal morphology of this species are similar to those of the few other studied species in the genus Echinaster. This study corroborates the notion that the mode of development--including a short-lived lecithotrophic brachiolaria larva--in all Echinaster species shares a similar pattern that may be conserved throughout the evolutionary history of the group. PMID:26896175

  4. CYGD: the Comprehensive Yeast Genome Database.

    PubMed

    Güldener, U; Münsterkötter, M; Kastenmüller, G; Strack, N; van Helden, J; Lemer, C; Richelles, J; Wodak, S J; García-Martínez, J; Pérez-Ortín, J E; Michael, H; Kaps, A; Talla, E; Dujon, B; André, B; Souciet, J L; De Montigny, J; Bon, E; Gaillardin, C; Mewes, H W

    2005-01-01

    The Comprehensive Yeast Genome Database (CYGD) compiles a comprehensive data resource for information on the cellular functions of the yeast Saccharomyces cerevisiae and related species, chosen as the best understood model organism for eukaryotes. The database serves as a common resource generated by a European consortium, going beyond the provision of sequence information and functional annotations on individual genes and proteins. In addition, it provides information on the physical and functional interactions among proteins as well as other genetic elements. These cellular networks include metabolic and regulatory pathways, signal transduction and transport processes as well as co-regulated gene clusters. As more yeast genomes are published, their annotation becomes greatly facilitated using S.cerevisiae as a reference. CYGD provides a way of exploring related genomes with the aid of the S.cerevisiae genome as a backbone and SIMAP, the Similarity Matrix of Proteins. The comprehensive resource is available under http://mips.gsf.de/genre/proj/yeast/. PMID:15608217

  5. CYGD: the Comprehensive Yeast Genome Database

    PubMed Central

    Güldener, U.; Münsterkötter, M.; Kastenmüller, G.; Strack, N.; van Helden, J.; Lemer, C.; Richelles, J.; Wodak, S. J.; García-Martínez, J.; Pérez-Ortín, J. E.; Michael, H.; Kaps, A.; Talla, E.; Dujon, B.; André, B.; Souciet, J. L.; De Montigny, J.; Bon, E.; Gaillardin, C.; Mewes, H. W.

    2005-01-01

    The Comprehensive Yeast Genome Database (CYGD) compiles a comprehensive data resource for information on the cellular functions of the yeast Saccharomyces cerevisiae and related species, chosen as the best understood model organism for eukaryotes. The database serves as a common resource generated by a European consortium, going beyond the provision of sequence information and functional annotations on individual genes and proteins. In addition, it provides information on the physical and functional interactions among proteins as well as other genetic elements. These cellular networks include metabolic and regulatory pathways, signal transduction and transport processes as well as co-regulated gene clusters. As more yeast genomes are published, their annotation becomes greatly facilitated using S.cerevisiae as a reference. CYGD provides a way of exploring related genomes with the aid of the S.cerevisiae genome as a backbone and SIMAP, the Similarity Matrix of Proteins. The comprehensive resource is available under http://mips.gsf.de/genre/proj/yeast/. PMID:15608217

  6. Protection from nitrosative stress by yeast flavohemoglobin

    PubMed Central

    Liu, Limin; Zeng, Ming; Hausladen, Alfred; Heitman, Joseph; Stamler, Jonathan S.

    2000-01-01

    Yeast hemoglobin was discovered close to half a century ago, but its function has remained unknown. Herein, we report that this flavohemoglobin protects Saccharomyces cerevisiae from nitrosative stress. Deletion of the flavohemoglobin gene (YHB1) abolished the nitric oxide (NO)-consuming activity of yeast cells. Levels of protein nitrosylation were more than 10-fold higher in yhb1 mutant yeast than in isogenic wild-type cells after incubation with NO donors. Growth of mutant cells was inhibited by a nitrosative challenge that had little effect on wild-type cells, whereas the resistance of mutant cells to oxidative stress was unimpaired. Protection conferred by yeast flavohemoglobin against NO and S-nitrosothiols was seen under both anaerobic and aerobic conditions, consistent with a primary function in NO detoxification. A phylogenetic analysis indicated that protection from nitrosative stress is likely to be a conserved function among microorganismal flavohemoglobins. Flavohemoglobin is therefore a potential target for antimicrobial therapy. PMID:10758168

  7. Genomic Evolution of the Ascomycete Yeasts

    SciTech Connect

    Riley, Robert; Haridas, Sajeet; Salamov, Asaf; Boundy-Mills, Kyria; Goker, Markus; Hittinger, Chris; Klenk, Hans-Peter; Lopes, Mariana; Meir-Kolthoff, Jan P.; Rokas, Antonis; Rosa, Carlos; Scheuner, Carmen; Soares, Marco; Stielow, Benjamin; Wisecaver, Jennifer H.; Wolfe, Ken; Blackwell, Meredith; Kurtzman, Cletus; Grigoriev, Igor; Jeffries, Thomas

    2015-03-16

    Yeasts are important for industrial and biotechnological processes and show remarkable metabolic and phylogenetic diversity despite morphological similarities. We have sequenced the genomes of 16 ascomycete yeasts of taxonomic and industrial importance including members of Saccharomycotina and Taphrinomycotina. Phylogenetic analysis of these and previously published yeast genomes helped resolve the placement of species including Saitoella complicata, Babjeviella inositovora, Hyphopichia burtonii, and Metschnikowia bicuspidata. Moreover, we find that alternative nuclear codon usage, where CUG encodes serine instead of leucine, are monophyletic within the Saccharomycotina. Most of the yeasts have compact genomes with a large fraction of single exon genes, and a tendency towards more introns in early-diverging species. Analysis of enzyme phylogeny gives insights into the evolution of metabolic capabilities such as methanol utilization and assimilation of alternative carbon sources.

  8. Monitoring Air Quality with Leaf Yeasts.

    ERIC Educational Resources Information Center

    Richardson, D. H. S.; And Others

    1985-01-01

    Proposes that leaf yeast serve as quick, inexpensive, and effective techniques for monitoring air quality. Outlines procedures and provides suggestions for data analysis. Includes results from sample school groups who employed this technique. (ML)

  9. [Regulation of gene expression in methylotrophic yeasts].

    PubMed

    Grabek-Lejko, Dorota; Sibirny, Vladimir; Sibirny, Andriy

    2013-01-01

    Methylotrophic yeasts are unique eukaryotic organisms, that can metabolize toxic one-carbon substrate, methyl alcohol or methanol. About 50 species of methylotrophic yeasts is known, among them 4 species are the best studied: Pichia methanolica, Hansenula polymorpha, Pichia pastoris i Candida boidinii. These organisms, especially P. pastoris i H. polymorpha appeared to be very perspective overproducers of heterologous proteins and nowadays are used for industrial production of some of them. In this review, we provide information on the organization of the genome, mechanisms of regulation of gene expression and the use of strong promoters of these yeast species to construct the producers of heterologous proteins. In more details, we analyze genetic control of carbon and nitrogen catabolic repression in H. polymorpha and also the identification of metabolites inducing catabolite repression or peroxisome selective autophagy in the medium with ethanol in the Pichia methanolica yeast. PMID:23821948

  10. IgM but not IgG monoclonal anti-Nocardia brasiliensis antibodies confer protection against experimental actinomycetoma in BALB/c mice.

    PubMed

    Gonzalez-Suarez, Maria L; Salinas-Carmona, Mario C; Pérez-Rivera, Isabel

    2009-10-01

    Nocardia brasiliensis is a facultative intracellular microorganism that produces a human chronic infection known as actinomycetoma. Human and mouse anti-N. brasiliensis antibody response identify P24, P26 and P61 immunodominant antigens. In this work, we generated immunoglobulin M (IgM) and IgG monoclonal antibodies (mAbs) specific to immunodominant P61 antigen. The monoclonal IgM (NbM1) and IgG2a (NbG1) antibodies were assessed for their in vitro bactericidal activity, in vivo protective effect and ability to block catalase activity. These mAbs specifically recognized P61, but they did not inhibit its enzyme activity. The in vitro bactericidal effect of NbG1 was higher than the killing ability of the IgM mAb. In vivo experiments with a murine model of experimental infection with N. brasiliensis injected into rear footpads was used to test the effect of NbM1 and NbG1. The negative untreated group developed a chronic actinomycetoma within 4 weeks. IgM mAbs conferred protection to BALB/c mice infected with N. brasiliensis. IgG mAb lacked this protective effect. IgM mAb showed a dose-response correlation between antibody concentration and lesion size. These results demonstrate that humoral immune response mediated by antigen-specific IgM antibody protects against an intracellular bacterial infection. PMID:19624737

  11. Whole-transcriptome survey of the putative ATP-binding cassette (ABC) transporter family genes in the latex-producing laticifers of Hevea brasiliensis.

    PubMed

    Zhiyi, Nie; Guijuan, Kang; Yu, Li; Longjun, Dai; Rizhong, Zeng

    2015-01-01

    The ATP-binding cassette (ABC) proteins or transporters constitute a large protein family in plants and are involved in many different cellular functions and processes, including solute transportation, channel regulation and molecular switches, etc. Through transcriptome sequencing, a transcriptome-wide survey and expression analysis of the ABC protein genes were carried out using the laticiferous latex from Hevea brasiliensis (rubber tree). A total of 46 putative ABC family proteins were identified in the H. brasiliensis latex. These consisted of 12 'full-size', 21 'half-size' and 13 other putative ABC proteins, and all of them showed strong conservation with their Arabidopsis thaliana counterparts. This study indicated that all eight plant ABC protein paralog subfamilies were identified in the H. brasiliensis latex, of which ABCB, ABCG and ABCI were the most abundant. Real-time quantitative reverse transcription-polymerase chain reaction assays demonstrated that gene expression of several latex ABC proteins was regulated by ethylene, jasmonic acid or bark tapping (a wound stress) stimulation, and that HbABCB15, HbABCB19, HbABCD1 and HbABCG21 responded most significantly of all to the abiotic stresses. The identification and expression analysis of the latex ABC family proteins could facilitate further investigation into their physiological involvement in latex metabolism and rubber biosynthesis by H. brasiliensis. PMID:25615936

  12. Whole-Transcriptome Survey of the Putative ATP-Binding Cassette (ABC) Transporter Family Genes in the Latex-Producing Laticifers of Hevea brasiliensis

    PubMed Central

    Zhiyi, Nie; Guijuan, Kang; Yu, Li; Longjun, Dai; Rizhong, Zeng

    2015-01-01

    The ATP-binding cassette (ABC) proteins or transporters constitute a large protein family in plants and are involved in many different cellular functions and processes, including solute transportation, channel regulation and molecular switches, etc. Through transcriptome sequencing, a transcriptome-wide survey and expression analysis of the ABC protein genes were carried out using the laticiferous latex from Hevea brasiliensis (rubber tree). A total of 46 putative ABC family proteins were identified in the H. brasiliensis latex. These consisted of 12 ‘full-size’, 21 ‘half-size’ and 13 other putative ABC proteins, and all of them showed strong conservation with their Arabidopsis thaliana counterparts. This study indicated that all eight plant ABC protein paralog subfamilies were identified in the H. brasiliensis latex, of which ABCB, ABCG and ABCI were the most abundant. Real-time quantitative reverse transcription-polymerase chain reaction assays demonstrated that gene expression of several latex ABC proteins was regulated by ethylene, jasmonic acid or bark tapping (a wound stress) stimulation, and that HbABCB15, HbABCB19, HbABCD1 and HbABCG21 responded most significantly of all to the abiotic stresses. The identification and expression analysis of the latex ABC family proteins could facilitate further investigation into their physiological involvement in latex metabolism and rubber biosynthesis by H. brasiliensis. PMID:25615936

  13. Multidrug resistant yeasts in synanthropic wild birds

    PubMed Central

    2010-01-01

    Background The aim of this study was to investigate the presence of multidrug resistant yeasts in the faeces of synanthropic wild birds from the Bangsar suburb of Kuala Lumpur. Methods Species characterisations of yeast isolates and determinations of antimycotic susceptibility profiles were undertaken using the commercial characterization kit, Integral System Yeasts Plus (Liofilchem, Italy). Results Fourteen species of yeasts were detected in the bird faecal samples.Candida albicans was present in 28.89% of bird faecal samples, Candida krusei (13.33%), Candida tropicalis (4.44%), Candida glabrata (4.44%), Candida parapsilosis (2.22%), Candida lambica (2.22%), Candida stellatoidea (2.22%), Candida rugosa (2.22%) and Candida lusitaniae (2.22%). Amongst the non-candidal yeast isolates, Cryptococcus laurentii was present in 6.67% of bird faecal samples, Cryptococcus uniguttulatus (4.44%), Saccharomyces cerevisiae (4.44%), Trichosporon pullulans (2.22%), Trichosporon pullulans/Cryptococcus albidus (8.89%) and Rhodotorula rubra/Rhodotorula glutinis (4.44%). Of the isolated yeasts, 18.1% (or 26/144) were found to be resistant to all 11 antimycotic agents they were tested against i.e. Nystatin, Amphotericin B, Flucytosine, Econazole, Ketoconazole, Clotrimazole, Miconazole, Itraconazole, Voriconazole, Fluconazole 16 and Fluconazole 64. 45.8% (or 66/144) of the bird faecal yeast isolates were resistant to four or more of the 11 antimycotic agents they were tested against. Conclusions This finding is of public health significance as these synanthropic wild birds may be reservoirs for transmission of drug resistant yeast infections to humans. PMID:20307325

  14. Metallothionein function and genetic regulation in yeast

    SciTech Connect

    Ecker, D.J.; Butt, T.R.; Crooke, S.T.

    1986-05-01

    Copper resistance in yeast is mediated by the CUP1 locus which codes for yeast metallothionein (MT). A genetic approach was taken to study yeast MT gene regulation and to test the function of MT in the detoxification of metal ions other than copper. A yeast strain was constructed (cup1/sup ..delta../) in which the MT structural and regulatory sequences were deleted. The deleted gene was then replaced with the following genetically modified forms of MT on high copy episomal plasmid (YE/sup p/ 13): 1) the intact yeast gene with normal structural and regulatory sequences; 2) a constitutively expressed yeast promoter (TDH) running the yeast MT structural gene. Metal resistance in the cup1/sup ..delta../ strain and the cup1/sup ..delta../ strain transformed with the MT plasmid constructions was compared on metal-supplemented agar plates. Both of the high copy MT plasmids conferred in excess of 500-fold greater copper resistance to the cup1/sup ..delta../ strain. Increased cadmium resistance was not observed in any of the strains that had MT under normal regulatory control. However, the strain with constitutively expressed MT was in excess of 1000-fold more resistant to cadmium. Neither of the MT constructions conferred resistance to Hg,Zn,Co,Ni,Ag,Au,Pt,La,U or Sn. MT gene induction measured by the analysis of MT mRNA on northern blots showed that the yeast MT promoter is not induced by Cd, Zn, Au, Hg, Ag, superoxide, hydrogen peroxide, steroid hormones or heat shock.

  15. Polysaccharides from Agaricus bisporus and Agaricus brasiliensis show similarities in their structures and their immunomodulatory effects on human monocytic THP-1 cells

    PubMed Central

    2011-01-01

    Background Mushroom polysaccharides have traditionally been used for the prevention and treatment of a multitude of disorders like infectious illnesses, cancers and various autoimmune diseases. Crude mushroom extracts have been tested without detailed chemical analyses of its polysaccharide content. For the present study we decided to chemically determine the carbohydrate composition of semi-purified extracts from 2 closely related and well known basidiomycete species, i.e. Agaricus bisporus and A. brasiliensis and to study their effects on the innate immune system, in particular on the in vitro induction of pro-inflammatory cytokines, using THP-1 cells. Methods Mushroom polysaccharide extracts were prepared by hot water extraction and precipitation with ethanol. Their composition was analyzed by GC-MS and NMR spectroscopy. PMA activated THP-1 cells were treated with the extracts under different conditions and the production of pro-inflammatory cytokines was evaluated by qPCR. Results Semi-purified polysaccharide extracts of A. bisporus and A. brasiliensis (= blazei) were found to contain (1?6),(1?4)-linked ?-glucan, (1?6)-linked ?-glucan, and mannogalactan. Their proportions were determined by integration of 1H-NMR signs, and were considerably different for the two species. A. brasiliensis showed a higher content of ?-glucan, while A. bisporus presented mannogalactan as its main polysaccharide. The extracts induced a comparable increase of transcription of the pro-inflammatory cytokine genes IL-1? and TNF-? as well as of COX-2 in PMA differentiated THP-1 cells. Pro-inflammatory effects of bacterial LPS in this assay could be reduced significantly by the simultaneous addition of A. brasiliensis extract. Conclusions The polysaccharide preparations from the closely related species A. bisporus and A. brasiliensis show major differences in composition: A. bisporus shows high mannogalactan content whereas A. brasiliensis has mostly ?-glucan. Semi-purified polysaccharide extracts from both Agaricus species stimulated the production of pro-inflammatory cytokines and enzymes, while the polysaccharide extract of A. brasiliensis reduced synthesis of these cytokines induced by LPS, suggesting programmable immunomodulation. PMID:21787425

  16. Physiological and environmental control of yeast prions

    PubMed Central

    Chernova, Tatiana A.; Wilkinson, Keith D.; Chernoff, Yury O.

    2014-01-01

    Prions are self-perpetuating protein isoforms that cause fatal and incurable neurodegenerative disease in mammals. Recent evidence indicates that a majority of human proteins involved in amyloid and neural inclusion disorders possess at least some prion properties. In lower eukaryotes, such as yeast, prions act as epigenetic elements, which increase phenotypic diversity by altering a range of cellular processes. While some yeast prions are clearly pathogenic, it is also postulated that prion formation could be beneficial in variable environmental conditions. Yeast and mammalian prions have similar molecular properties. Crucial cellular factors and conditions influencing prion formation and propagation were uncovered in the yeast models. Stress-related chaperones, protein quality control deposits, degradation pathways and cytoskeletal networks control prion formation and propagation in yeast. Environmental stresses trigger prion formation and loss, supposedly acting via influencing intracellular concentrations of the prion-inducing proteins, and/or by localizing prionogenic proteins to the prion induction sites via heterologous ancillary helpers. Physiological and environmental modulation of yeast prions points to new opportunities for pharmacological intervention and/or prophylactic measures targeting general cellular systems rather than the properties of individual amyloids and prions. PMID:24236638

  17. The growth of solar radiated yeast

    SciTech Connect

    Kraft, T.

    1995-09-01

    This researcher plans to determine if solar radiation affects the growth of yeast. The irradiated yeast was obtained from a sample exposed in space during a Space Shuttle flight of September 9-20, 1994. Further, the control groups were held at: (1) Goddard Space Flight Center (GSFC) in Greenbelt, Maryland; and (2) South Dakota School of Mines and Technology. The procedure used was based on the fact that yeast is most often used in consumable baked goods. Therefore, the yeast was incorporated into a basic Betty Crocker bread recipe. Data was collected by placing measured amounts of dough into sample containers with fifteen minute growth in height measurements collected and recorded. This researcher assumed the viability of yeast to be relative to its ability to produce carbon dioxide gas and cause the dough to rise. As all ingredients and surroundings were equal, this researcher assumed the yeast will produce the only significant difference in data collected. This researcher noted the approximate use date on all sample packages to be prior to arrival and experiment date. All dates equal, it was then assumed each would act in a similar manner of response. This assumption will allow for equally correct data collection.

  18. The growth of solar radiated yeast

    NASA Technical Reports Server (NTRS)

    Kraft, Tyrone

    1995-01-01

    This researcher plans to determine if solar radiation affects the growth of yeast. The irradiated yeast was obtained from a sample exposed in space during a Space Shuttle flight of September 9-20, 1994. Further, the control groups were held at: (1) Goddard Space Flight Center (GSFC) in Greenbelt, Maryland; and (2) South Dakota School of Mines and Technology. The procedure used was based on the fact that yeast is most often used in consumable baked goods. Therefore, the yeast was incorporated into a basic Betty Crocker bread recipe. Data was collected by placing measured amounts of dough into sample containers with fifteen minute growth in height measurements collected and recorded. This researcher assumed the viability of yeast to be relative to its ability to produce carbon dioxide gas and cause the dough to rise. As all ingredients and surroundings were equal, this researcher assumed the yeast will produce the only significant difference in data collected. This researcher noted the approximate use date on all sample packages to be prior to arrival and experiment date. All dates equal, it was then assumed each would act in a similar manner of response. This assumption will allow for equally correct data collection.

  19. Yeast prions assembly and propagation

    PubMed Central

    2011-01-01

    Yeast prions are self-perpetuating protein aggregates that are at the origin of heritable and transmissible non-Mendelian phenotypic traits. Among these, [PSI+], [URE3] and [PIN+] are the most well documented prions and arise from the assembly of Sup35p, Ure2p and Rnq1p, respectively, into insoluble fibrillar assemblies. Fibril assembly depends on the presence of N- or C-terminal prion domains (PrDs) which are not homologous in sequence but share unusual amino-acid compositions, such as enrichment in polar residues (glutamines and asparagines) or the presence of oligopeptide repeats. Purified PrDs form amyloid fibrils that can convert prion-free cells to the prion state upon transformation. Nonetheless, isolated PrDs and full-length prion proteins have different aggregation, structural and infectious properties. In addition, mutations in the “non-prion” domains (non-PrDs) of Sup35p, Ure2p and Rnq1p were shown to affect their prion properties in vitro and in vivo. Despite these evidences, the implication of the functional non-PrDs in fibril assembly and prion propagation has been mostly overlooked. In this review, we discuss the contribution of non-PrDs to prion assemblies, and the structure-function relationship in prion infectivity in the light of recent findings on Sup35p and Ure2p assembly into infectious fibrils from our laboratory and others. PMID:22052349

  20. Training of yeast cell dynamics.

    PubMed

    Reijenga, Karin A; Bakker, Barbara M; van der Weijden, Coen C; Westerhoff, Hans V

    2005-04-01

    In both industrial fermenters and in their natural habitats, microorganisms often experience an inhomogeneous and fluctuating environment. In this paper we mimicked one aspect of this nonideal behaviour by imposing a low and oscillating extracellular glucose concentration on nonoscillating suspensions of yeast cells. The extracellular dynamics changed the intracellular dynamics--which was monitored through NADH fluorescence--from steady to equally dynamic; the latter followed the extracellular dynamics at the frequency of glucose pulsing. Interestingly, the amplitude of the oscillation of the NADH fluorescence increased with time. This increase in amplitude was sensitive to inhibition of protein synthesis, and was due to a change in the cells rather than in the medium; the cell population was 'trained' to respond to the extracellular dynamics. To examine the mechanism behind this 'training', we subjected the cells to a low and constant extracellular glucose concentration. Seventy-five minutes of adaptation to a low and constant glucose concentration induced the same increase of the amplitude of the forced NADH oscillations as did the train of glucose pulses. Furthermore, 75 min of adaptation to a low (oscillating or continuous) glucose concentration decreased the K(M) of the glucose transporter from 26 mm to 3.5 mm. When subsequently the apparent K(M) was increased by addition of maltose, the amplitude of the forced oscillations dropped to its original value. This demonstrated that the increased affinity of glucose transport was essential for the training of the cells' dynamics. PMID:15794749

  1. The One Hour Yeast Proteome*

    PubMed Central

    Hebert, Alexander S.; Richards, Alicia L.; Bailey, Derek J.; Ulbrich, Arne; Coughlin, Emma E.; Westphall, Michael S.; Coon, Joshua J.

    2014-01-01

    We describe the comprehensive analysis of the yeast proteome in just over one hour of optimized analysis. We achieve this expedited proteome characterization with improved sample preparation, chromatographic separations, and by using a new Orbitrap hybrid mass spectrometer equipped with a mass filter, a collision cell, a high-field Orbitrap analyzer, and, finally, a dual cell linear ion trap analyzer (Q-OT-qIT, Orbitrap Fusion). This system offers high MS2 acquisition speed of 20 Hz and detects up to 19 peptide sequences within a single second of operation. Over a 1.3 h chromatographic method, the Q-OT-qIT hybrid collected an average of 13,447 MS1 and 80,460 MS2 scans (per run) to produce 43,400 (x̄) peptide spectral matches and 34,255 (x̄) peptides with unique amino acid sequences (1% false discovery rate (FDR)). On average, each one hour analysis achieved detection of 3,977 proteins (1% FDR). We conclude that further improvements in mass spectrometer scan rate could render comprehensive analysis of the human proteome within a few hours. PMID:24143002

  2. How Do Rubber (Hevea brasiliensis) Plantations Cope with Seasonal Drought in Northern Thailand and Central Cambodia?

    NASA Astrophysics Data System (ADS)

    Kumagai, T.; Giambelluca, T. W.

    2014-12-01

    Rubber (Hevea brasiliensis Müll. Arg.) plantaitons are rapidly expanding throughout mainland Southeast Asia, potentially changing the partitioning of water, energy, and carbon at multiple scales, compared with the traditional land covers they are replacing. We have conducted eddy flux measurements in two rubber plantation sites: Som Sanuk (SS), located northern Thailand; and Cambodian Rubber Research Institute (CRRI), central Cambodia. We used combination of actual evapotranspiration (ET) flux measurements and an inversed version of a simple 2-layer ET model for estimating the mean canopy stomatal conductances (gs), which is among the most effective measures for describing the exchange characteristics. It is demonstrated how each studied rubber plantation copes with each strong seasonal drought via tree water use strategies. Potential tree water use deficit (precipitation (P) - potential evaporation (ET_POT)) for each season (i.e., December-February: DJF, March-May: MAM, June-August: JJA, and September-November: SON) revealed in which season and how the water use should be controlled. We found that in the season when actual tree water use deficit (P - ET) was negative (DJF and MAM), the deficit was compensated with soil water from the previous season at a depth of 0-2 m at the Thailand site, and from a depth of 0-3 m at CRRI. Two ecophysiological parameters, the reference value of gs (gsref) and the sensitivity of gs to atmospheric demand (m), as well as their proportionality (m/gsref), were derived from the logarithmic response curve of gs to vapor pressure deficit (D) for each season and each site. In both sites, gsref and m appeared to be less in DJF and MAM than each in the other three month periods (seasons). On average in a whole year, m/gsref was less than 0.6 at SS and almost 0.6 at the CRRI site, suggesting that there was less sufficient stomatal regulation at SS, where there might be little risk of water stress-induced hydraulic failure because of much annual rainfall amount. In comparison, at CRRI where annual P - ET_POT was negative, there was stricter stomatal regulation, preventing excessive xylem cavitation. These tendencies imply that in the drier season, i.e., DJF and MAM, the rubber trees in SS and CRRI adopt the stomatal control strategy of changing gsref with reluctance and positive to change m, respectively.

  3. RNA sequencing read depth requirement for optimal transcriptome coverage in Hevea brasiliensis

    PubMed Central

    2014-01-01

    Background One of the concerns of assembling de novo transcriptomes is determining the amount of read sequences required to ensure a comprehensive coverage of genes expressed in a particular sample. In this report, we describe the use of Illumina paired-end RNA-Seq (PE RNA-Seq) reads from Hevea brasiliensis (rubber tree) bark to devise a transcript mapping approach for the estimation of the read amount needed for deep transcriptome coverage. Findings We optimized the assembly of a Hevea bark transcriptome based on 16 Gb Illumina PE RNA-Seq reads using the Oases assembler across a range of k-mer sizes. We then assessed assembly quality based on transcript N50 length and transcript mapping statistics in relation to (a) known Hevea cDNAs with complete open reading frames, (b) a set of core eukaryotic genes and (c) Hevea genome scaffolds. This was followed by a systematic transcript mapping process where sub-assemblies from a series of incremental amounts of bark transcripts were aligned to transcripts from the entire bark transcriptome assembly. The exercise served to relate read amounts to the degree of transcript mapping level, the latter being an indicator of the coverage of gene transcripts expressed in the sample. As read amounts or datasize increased toward 16 Gb, the number of transcripts mapped to the entire bark assembly approached saturation. A colour matrix was subsequently generated to illustrate sequencing depth requirement in relation to the degree of coverage of total sample transcripts. Conclusions We devised a procedure, the “transcript mapping saturation test”, to estimate the amount of RNA-Seq reads needed for deep coverage of transcriptomes. For Hevea de novo assembly, we propose generating between 5–8 Gb reads, whereby around 90% transcript coverage could be achieved with optimized k-mers and transcript N50 length. The principle behind this methodology may also be applied to other non-model plants, or with reads from other second generation sequencing platforms. PMID:24484543

  4. Discussion of teleomorphic and anamorphic Ascomycetous yeasts and yeast-like taxa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The relationship of ascomycetous yeasts with other members of the ascomycete fungi (Ascomycota) has been controversial for over 100 years. Because yeasts are morphologically simple, it was proposed that they represent primitive forms of ascomycetes (e.g., Guilliermond 1912). Alternatively, the ide...

  5. Boolean Model of Yeast Apoptosis as a Tool to Study Yeast and Human Apoptotic Regulations

    PubMed Central

    Kazemzadeh, Laleh; Cvijovic, Marija; Petranovic, Dina

    2012-01-01

    Programmed cell death (PCD) is an essential cellular mechanism that is evolutionary conserved, mediated through various pathways and acts by integrating different stimuli. Many diseases such as neurodegenerative diseases and cancers are found to be caused by, or associated with, regulations in the cell death pathways. Yeast Saccharomyces cerevisiae, is a unicellular eukaryotic organism that shares with human cells components and pathways of the PCD and is therefore used as a model organism. Boolean modeling is becoming promising approach to capture qualitative behavior and describe essential properties of such complex networks. Here we present large literature-based and to our knowledge first Boolean model that combines pathways leading to apoptosis (a type of PCD) in yeast. Analysis of the yeast model confirmed experimental findings of anti-apoptotic role of Bir1p and pro-apoptotic role of Stm1p and revealed activation of the stress protein kinase Hog proposing the maximal level of activation upon heat stress. In addition we extended the yeast model and created an in silico humanized yeast in which human pro- and anti-apoptotic regulators Bcl-2 family and Valosin-contain protein (VCP) are included in the model. We showed that accumulation of Bax in silico humanized yeast shows apoptotic markers and that VCP is essential target of Akt Signaling. The presented Boolean model provides comprehensive description of yeast apoptosis network behavior. Extended model of humanized yeast gives new insights of how complex human disease like neurodegeneration can initially be tested. PMID:23233838

  6. Plasmodium chabaudi limits early Nippostrongylus brasiliensis-induced pulmonary immune activation and Th2 polarization in co-infected mice

    PubMed Central

    2009-01-01

    Background Larvae of several common species of parasitic nematodes obligately migrate through, and often damage, host lungs. The larvae induce strong pulmonary Type 2 immune responses, including T-helper (Th)2 cells as well as alternatively activated macrophages (AAM?) and associated chitinase and Fizz/resistin family members (ChaFFs), which are thought to promote tissue repair processes. Given the prevalence of systemic or lung-resident Type 1-inducing pathogens in geographical areas in which nematodes are endemic, we wished to investigate the impact of concurrent Type 1 responses on the development of these Type 2 responses to nematode larval migration. We therefore infected BALB/c mice with the nematode Nippostrongylus brasiliensis, in the presence or absence of Plasmodium chabaudi chabaudi malaria parasites. Co-infected animals received both infections on the same day, and disease was assessed daily before immunological measurements were taken at 3, 5, 7 or 20 days post-infection. Results We observed that the nematodes themselves caused transient loss of body mass and red blood cell density, but co-infection then slightly ameliorated the severity of malarial anaemia. We also tracked the development of immune responses in the lung and thoracic lymph node. By the time of onset of the adaptive immune response around 7 days post-infection, malaria co-infection had reduced pulmonary expression of ChaFFs. Assessment of the T cell response demonstrated that the Th2 response to the nematode was also significantly impaired by malaria co-infection. Conclusion P. c. chabaudi co-infection altered both local and lymph node Type 2 immune activation due to migration of N. brasiliensis larvae. Given recent work from other laboratories showing that N. brasiliensis-induced ChaFFs correlate to the extent of long-term lung damage, our results raise the possibility that co-infection with malaria might alter pulmonary repair processes following nematode migration. Further experimentation in the co-infection model developed here will reveal the longer-term consequences of the presence of both malaria and helminths in the lung. PMID:19951425

  7. Lacaziosis-like disease in Tursiops truncatus from Brazil: a histopathological and immunohistochemical approach.

    PubMed

    Sacristán, Carlos; Réssio, Rodrigo Albergaria; Castilho, Pedro; Fernandes, Natália; Costa-Silva, Samira; Esperón, Fernando; Daura-Jorge, Fábio Gonçalves; Groch, Kátia R; Kolesnikovas, Cristiane K M; Marigo, Juliana; Ott, Paulo Henrique; Oliveira, Larissa Rosa; Sánchez-Sarmiento, Angélica María; Simões-Lopes, Paulo C; Catão-Dias, José Luiz

    2016-01-13

    Cetacean lacaziosis-like disease or lobomycosis-like disease (LLD) is a chronic skin condition caused by a non-cultivable yeast of the order Onygenales, which also includes Lacazia loboi, as well as Paracoccidioides brasiliensis and P. lutzii, respectively responsible for lacaziosis and paracoccidioidomycosis in humans. Complete identification and phylogenetic classification of the LLD etiological agent still needs to be elucidated, but preliminary phylogenetic analyses have shown a closer relationship of the LLD agent to Paracoccidioides spp. than to L. loboi. Cases of LLD in South American cetaceans based on photographic identification have been reported; however, to date, only 3 histologically confirmed cases of LLD have been described. We evaluated multiple tissue samples from 4 Tursiops truncatus stranded in the states of Santa Catarina (n = 3) and Rio Grande do Sul (n = 1), southern Brazil. Macroscopically, all animals presented lesions consistent with LLD. Hematoxylin-eosin, periodic acid-Schiff, Grocott's methenamine silver, and Mayer's mucicarmin stains were used for histological evaluation. Microscopically, numerous refractile yeasts (4-9 µm in diameter) were observed in skin samples (4/4), and for the first time in dolphins, also in a skeletal muscle abscess (1/4). Immunohistochemistry using anti-P. brasiliensis glycoprotein gp43 as a primary antibody, which is known to cross-react with L. loboi and the LLD agent, was performed and results were positive in all 4 cases. We describe 3 new cases of LLD in cetaceans based on histopathology and immunohistochemistry. This is the first report of LLD in the muscle of cetaceans. PMID:26758656

  8. Yeast fuel cell: Application for desalination

    NASA Astrophysics Data System (ADS)

    Mardiana, Ummy; Innocent, Christophe; Cretin, Marc; Buchari, Buchari; Gandasasmita, Suryo

    2016-02-01

    Yeasts have been implicated in microbial fuel cells as biocatalysts because they are non-pathogenic organisms, easily handled and robust with a good tolerance in different environmental conditions. Here we investigated baker's yeast Saccharomyces cerevisiae through the oxidation of glucose. Yeast was used in the anolyte, to transfer electrons to the anode in the presence of methylene blue as mediator whereas K3Fe(CN)6 was used as an electron acceptor for the reduction reaction in the catholyte. Power production with biofuel cell was coupled with a desalination process. The maximum current density produced by the cell was 88 mA.m-2. In those conditions, it was found that concentration of salt was removed 64% from initial 0.6 M after 1-month operation. This result proves that yeast fuel cells can be used to remove salt through electrically driven membrane processes and demonstrated that could be applied for energy production and desalination. Further developments are in progress to improve power output to make yeast fuel cells applicable for water treatment.

  9. Ecology of pathogenic yeasts in Amazonian soil.

    PubMed

    Mok, W Y; Luizão, R C; do Socorro Barreto da Silva, M; Teixeira, M F; Muniz, E G

    1984-02-01

    In an investigation of Amazonian soil as a natural reservoir for pathogenic fungi, 1,949 soil samples collected from diverse geographical and ecological settings of the Brazilian Amazon Basin were analyzed for the presence of non-keratinophilic fungi by the indirect mouse inoculation procedure and for the presence of keratinophilic fungi by the hair bait technique. All soil samples were acidic with low pH values. From 12% of the soil samples, 241 yeast and yeastlike isolates pertaining to six genera and 82 species were recovered, of which 63% were Torulopsis and 26% were Candida species. Nine fungi with known pathogenic potentials were encountered among 43% (104) of the isolates: T. glabrata, C. guilliermondii, C. albicans, C. pseudotropicalis, C. stellatoidea, C. tropicalis, Rhodotorula rubra, and Wangiella dermatitidis. The yeast flora was marked by species diversity, low frequency of each species, random geographical distribution, and an apparent lack of species clustering. The composition and distribution of the yeast flora in soil differed from those of the yeast flora harbored by bats, suggesting that the Amazonian external environment and internal bat organs act as independent natural habitats for yeasts. PMID:6538774

  10. Mitochondrial membrane lipidome defines yeast longevity.

    PubMed

    Beach, Adam; Richard, Vincent R; Leonov, Anna; Burstein, Michelle T; Bourque, Simon D; Koupaki, Olivia; Juneau, Mylène; Feldman, Rachel; Iouk, Tatiana; Titorenko, Vladimir I

    2013-07-01

    Our studies revealed that lithocholic acid (LCA), a bile acid, is a potent anti-aging natural compound that in yeast cultured under longevity-extending caloric restriction (CR) conditions acts in synergy with CR to enable a significant further increase in chronological lifespan. Here, we investigate a mechanism underlying this robust longevity-extending effect of LCA under CR. We found that exogenously added LCA enters yeast cells, is sorted to mitochondria, resides mainly in the inner mitochondrial membrane, and also associates with the outer mitochondrial membrane. LCA elicits an age-related remodeling of glycerophospholipid synthesis and movement within both mitochondrial membranes, thereby causing substantial changes in mitochondrial membrane lipidome and triggering major changes in mitochondrial size, number and morphology. In synergy, these changes in the membrane lipidome and morphology of mitochondria alter the age-related chronology of mitochondrial respiration, membrane potential, ATP synthesis and reactive oxygen species homeostasis. The LCA-driven alterations in the age-related dynamics of these vital mitochondrial processes extend yeast longevity. In sum, our findings suggest a mechanism underlying the ability of LCA to delay chronological aging in yeast by accumulating in both mitochondrial membranes and altering their glycerophospholipid compositions. We concluded that mitochondrial membrane lipidome plays an essential role in defining yeast longevity. PMID:23924582

  11. Modeling Diauxic Glycolytic Oscillations in Yeast

    PubMed Central

    Hald, Bjørn Olav; Sørensen, Preben G.

    2010-01-01

    Glycolytic oscillations in a stirred suspension of starved yeast cells is an excellent model system for studying the dynamics of metabolic switching in living systems. In an open-flow system the oscillations can be maintained indefinitely at a constant operating point where they can be characterized quantitatively by experimental quenching and bifurcation analysis. In this article, we use these methods to show that the dynamics of oscillations in a closed system is a simple transient version of the open-system dynamics. Thus, easy-setup closed-system experiments are also useful for investigations of central metabolism dynamics of yeast cells. We have previously proposed a model for the open system comprised of the primary fermentative reactions in yeast that quantitatively describes the oscillatory dynamics. However, this model fails to describe the transient behavior of metabolic switching in a closed-system experiment by feeding the yeast suspension with a glucose pulse—notably the initial NADH spike and final NADH rise. Another object of this study is to gain insight into the secondary low-flux metabolic pathways by feeding starved yeast cells with various metabolites. Experimental and computational results strongly suggest that regulation of acetaldehyde explains the observed behavior. We have extended the original model with regulation of pyruvate decarboxylase, a reversible alcohol dehydrogenase, and drainage of pyruvate. Using the method of time rescaling in the extended model, the description of the transient closed-system experiments is significantly improved. PMID:21081066

  12. Influence of pesticides on yeasts colonizing leaves.

    PubMed

    Vadkertiová, Renata; Sláviková, Elena

    2011-01-01

    The effect of nine different pesticides on the growth of yeasts isolated from the leaves of fruit and forest trees was investigated. Four insecticides (with the active ingredients: thiacloprid, deltamethrin, lambdacyhalothrin, and thiamethoxam) and five fungicides (with the effective substances: bitertanol, kresoxim-methyl, mancozeb, trifloxystrobin, and cupric oxychloride) were tested. The concentrations of chemicals were those recommended by the manufacturers for the spraying of trees. The yeast strains isolated from the leaves of fruit trees were not sensitive to any of the insecticides. The majority of yeast strains isolated from the leaves of forest trees were either not sensitive or only to a small extent. While Rhodotorula mucilaginosa and Pichia anomala were not affected by any insecticide, the strains of Cryptococcus laurentii and Rhodotorula glutinis showed the highest sensitivity. The effects of fungicides on the growth of isolated yeasts were more substantial. The fungicide Dithane DG (mancozeb) completely inhibited the growth of all yeasts. All strains isolated from fruit tree leaves were more resistant to the tested fungicides than those isolated from the leaves of forest trees. The most resistant strains from the leaves of fruit trees belonged to the species Metschnikowia pulcherrima, Pichia anomala, and Saccharomyces cerevisiae, whereas Cryptococcus albidus and C. laurentii, originating from the leaves of forest trees, showed the highest sensitivity to fungicides. PMID:22351984

  13. Chapter 6: The genomes of lager yeasts.

    PubMed

    Bond, Ursula

    2009-01-01

    Yeasts used in the production of lagers belong to the genus Saccharomyces pastorianus. Species within this genus arose from a natural hybridization event between two yeast species that appear to be closely related to Saccharomyces cerevisiae and Saccharomyces bayanus. The resultant hybrids contain complex allopolyploid genomes and retain genetic characteristics of both parental species. Recent genome analysis using both whole genome sequencing and competitive genomic hybridization techniques has revealed the underlying composition of lager yeasts genomes. There appear to be at least 36 unique chromosomes, many of which are lager specific, resulting from recombination events between the homeologous parental chromosomes. The recombination events are limited to a defined set of genetic loci, which are highly conserved within strains of lager yeasts. In addition to the hybrid chromosomes, several non-reciprocal chromosomal translocations and inversions are also observed. Remarkably, in response to exposure to environmental stresses such as high temperatures and high osmotic pressure, the genomes appear to be highly dynamic and undergo recombination events at defined loci and alterations in the telomeric regions. The ability of environmental stress to alter the structure and composition of the genomes of lager yeasts may point to mechanisms of adaptive evolution in these species. PMID:19729094

  14. Production of alpha-amylase by yeast

    SciTech Connect

    Thomse, K.K.

    1987-01-01

    The enzyme alpha-amylase confers to an organism the enzymatic activity for the degradation of polyglucosides with alpha-1,4 glycosidic bonds such as starch and glycogen which are among the major storage compounds in plants and animals. Most alpha-amylases are single polypeptides of molecular weights around 50,000 dalton. They are generally found in the digestive tract of animals and in germinating seeds. Among the products released upon enzymatic degradation of polyglucosides maltose, a sugar that can be utilized as carbon source by yeast, is a major constituent. A cDNA segment complementary to mouse salivary amylase messenger RNA has been inserted into the yeast expression vector pMA56 behind the promoter of the gene encoding alcohol dehydrogenase I of yeast. Yeast transforma