WorldWideScience

Sample records for aspergillus nidulans genome

  1. Analysis of Aspergillus nidulans metabolism at the genome-scale

    DEFF Research Database (Denmark)

    David, Helga; Ozcelik, İlknur Ş; Hofmann, Gerald;

    2008-01-01

    a function. Results: In this work, we have manually assigned functions to 472 orphan genes in the metabolism of A. nidulans, by using a pathway-driven approach and by employing comparative genomics tools based on sequence similarity. The central metabolism of A. nidulans, as well as biosynthetic pathways......, in an objective and systematic manner. The functional assignments served as a basis to develop a mathematical model, linking 666 genes (both previously and newly annotated) to metabolic roles. The model was used to simulate metabolic behavior and additionally to integrate, analyze and interpret large-scale gene...

  2. Post-genomic insights into the plant polysaccharide degradation potential of Aspergillus nidulans and comparison to Aspergillus niger and Aspergillus oryzae

    DEFF Research Database (Denmark)

    Coutinho, Pedro M.; Andersen, Mikael Rørdam; Kolenova, Katarina;

    2009-01-01

    The plant polysaccharide degradative potential of Aspergillus nidulans was analysed in detail and compared to that of Aspergillus niger and Aspergillus oryzae using a combination of bioinformatics, physiology and transcriptomics. Manual verification indicated that 28.4% of the A. nidulans ORFs...

  3. Mapping of polyketide biosynthesis pathways in Aspergillus nidulans using a genome wide PKS gene deletion library

    DEFF Research Database (Denmark)

    Larsen, Thomas Ostenfeld; Rank, Christian; Klejnstrup, Marie Louise;

    In order to map new links between PKS genes and their products in Aspergillus nidulans we have systematically deleted all thirty-two individual genes predicted to encode polyketide synthases in this model organism. This number greatly exceeds the number of currently known PKs calling for new...

  4. Selection arena in Aspergillus nidulans

    NARCIS (Netherlands)

    Bruggeman, J.; Debets, A.J.M.; Hoekstra, R.F.

    2004-01-01

    The selection arena hypothesis states that overproduction of zygotes-a widespread phenomenon in animals and plants-can be explained as a mechanism of progeny choice. As a similar mechanism, the ascomycetous fungus Aspergillus nidulans may overproduce dikaryotic fruit initials, hereafter called dikar

  5. Chemical analysis of a genome wide polyketide synthase gene deletion library in Aspergillus nidulans

    DEFF Research Database (Denmark)

    Larsen, Thomas Ostenfeld; Klejnstrup, Marie Louise; Nielsen, Jakob Blæsbjerg;

    predicted to encode polyketide synthases have been individually been deleted. This presentation will highlight our recent linking of secondary metabolites in A. nidulans to genes, and in particular describe some recent work on characterization of ANID_6448 and associated genes responsible for biosynthesis...

  6. Genetics of Polyketide Metabolism in Aspergillus nidulans

    DEFF Research Database (Denmark)

    Klejnstrup, Marie L.; Frandsen, Rasmus John Normand; Holm, Dorte Koefoed;

    2012-01-01

    are publicly available, greatly facilitating the establishment of links between genes and metabolites. This review covers the attempts being made to trigger the activation of polyketide metabolism in the fungal model organism Aspergillus nidulans. Moreover, it will provide an overview of the pathways where ten...

  7. A genome-wide polyketide synthase deletion library uncovers novel genetic links to polyketides and meroterpenoids in Aspergillus nidulans

    DEFF Research Database (Denmark)

    Nielsen, Michael Lynge; Nielsen, Jakob Blæsbjerg; Rank, Christian;

    2011-01-01

    Fungi possess an advanced secondary metabolism that is regulated and coordinated in a complex manner depending on environmental challenges. To understand this complexity, a holistic approach is necessary. We initiated such an analysis in the important model fungus Aspergillus nidulans by systemat...... the current understanding of the biosynthetic pathways leading to arugosins and violaceols. We expect that the library will be an important resource towards a systemic understanding of polyketide production in A. nidulans....... by systematically deleting all 32 individual genes encoding polyketide synthases. Wild-type and all mutant strains were challenged on different complex media to provoke induction of the secondary metabolism. Screening of the mutant library revealed direct genetic links to two austinol meroterpenoids and expanded...

  8. Genetics of Polyketide Metabolism in Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Marie L. Klejnstrup

    2012-01-01

    Full Text Available Secondary metabolites are small molecules that show large structural diversity and a broad range of bioactivities. Some metabolites are attractive as drugs or pigments while others act as harmful mycotoxins. Filamentous fungi have the capacity to produce a wide array of secondary metabolites including polyketides. The majority of genes required for production of these metabolites are mostly organized in gene clusters, which often are silent or barely expressed under laboratory conditions, making discovery and analysis difficult. Fortunately, the genome sequences of several filamentous fungi are publicly available, greatly facilitating the establishment of links between genes and metabolites. This review covers the attempts being made to trigger the activation of polyketide metabolism in the fungal model organism Aspergillus nidulans. Moreover, it will provide an overview of the pathways where ten polyketide synthase genes have been coupled to polyketide products. Therefore, the proposed biosynthesis of the following metabolites will be presented; naphthopyrone, sterigmatocystin, aspyridones, emericellamides, asperthecin, asperfuranone, monodictyphenone/emodin, orsellinic acid, and the austinols.

  9. The 2008 update of the Aspergillus nidulans genome annotation: A community effort

    DEFF Research Database (Denmark)

    Wortman, Jennifer Russo; Gilsenan, Jane Mabey; Joardar, Vinita;

    2009-01-01

    The identification and annotation of protein-coding genes is one of the primary goals of whole-genome sequencing projects, and the accuracy of predicting the primary protein products of gene expression is vital to the interpretation of the available data and the design of downstream functional ap...

  10. The 2008 update of the Aspergillus nidulans genome annotation : a community effort

    NARCIS (Netherlands)

    Wortman, Jennifer Russo; Gilsenan, Jane Mabey; Joardar, Vinita; Deegan, Jennifer; Clutterbuck, John; Andersen, Mikael R; Archer, David; Bencina, Mojca; Braus, Gerhard; Coutinho, Pedro; von Döhren, Hans; Doonan, John; Driessen, Arnold J M; Durek, Pawel; Espeso, Eduardo; Fekete, Erzsébet; Flipphi, Michel; Estrada, Carlos Garcia; Geysens, Steven; Goldman, Gustavo; de Groot, Piet W J; Hansen, Kim; Harris, Steven D; Heinekamp, Thorsten; Helmstaedt, Kerstin; Henrissat, Bernard; Hofmann, Gerald; Homan, Tim; Horio, Tetsuya; Horiuchi, Hiroyuki; James, Steve; Jones, Meriel; Karaffa, Levente; Karányi, Zsolt; Kato, Masashi; Keller, Nancy; Kelly, Diane E; Kiel, Jan A K W; Kim, Jung-Mi; van der Klei, Ida J; Klis, Frans M; Kovalchuk, Andriy; Krasevec, Nada; Kubicek, Christian P; Liu, Bo; Maccabe, Andrew; Meyer, Vera; Mirabito, Pete; Miskei, Márton; Mos, Magdalena; Mullins, Jonathan; Nelson, David R; Nielsen, Jens; Oakley, Berl R; Osmani, Stephen A; Pakula, Tiina; Paszewski, Andrzej; Paulsen, Ian; Pilsyk, Sebastian; Pócsi, István; Punt, Peter J; Ram, Arthur F J; Ren, Qinghu; Robellet, Xavier; Robson, Geoff; Seiboth, Bernhard; van Solingen, Piet; Specht, Thomas; Sun, Jibin; Taheri-Talesh, Naimeh; Takeshita, Norio; Ussery, Dave; vanKuyk, Patricia A; Visser, Hans; van de Vondervoort, Peter J I; de Vries, Ronald P; Walton, Jonathan; Xiang, Xin; Xiong, Yi; Zeng, An Ping; Brandt, Bernd W; Cornell, Michael J; van den Hondel, Cees A M J J; Visser, Jacob; Oliver, Stephen G; Turner, Geoffrey

    2009-01-01

    The identification and annotation of protein-coding genes is one of the primary goals of whole-genome sequencing projects, and the accuracy of predicting the primary protein products of gene expression is vital to the interpretation of the available data and the design of downstream functional appli

  11. The 2008 update of the Aspergillus nidulans genome annotation: A community effort

    NARCIS (Netherlands)

    J.R. Wortman; J.M. Gilsenan; V. Joardar; J. Deegan; J. Clutterbuck; M.R. Andersen; D. Archer; M. Bencina; G. Braus; P. Coutinho; H. von Döhren; J. Doonan; A.J.M. Driessen; P. Durek; E. Espeso; E. Fekete; M. Flipphi; C.G. Estrada; S. Geysens; G. Goldman; P.W.J. de Groot; K. Hansen; S.D. Harris; T. Heinekamp; K. Helmstaedt; B. Henrissat; G. Hofmann; T. Homan; T. Horio; H. Horiuchi; S. James; M. Jones; L. Karaffa; Z. Karányi; M. Kato; N. Keller; D.E. Kelly; J.A.K.W. Kiel; J.M. Kim; I.J. van der Klei; F.M. Klis; A. Kovalchuk; N. Kraševec; C.P. Kubicek; B. Liu; A. MacCabe; V. Meyer; P. Mirabito; M. Miskei; M. Mos; J. Mullins; D.R. Nelson; J. Nielsen; B.R. Oakley; S.A. Osmani; T. Pakula; A. Paszewski; I. Paulsen; S. Pilsyk; I. Pócsi; P.J. Punt; A.F.J. Ram; Q. Ren; X. Robellet; G. Robson; B. Seiboth; P. van Solingen; T. Specht; J. Sun; N. Taheri-Talesh; N. Takeshita; D. Ussery; P.A. vanKuyk; H. Visser; P.J.I. van de Vondervoort; R.P. de Vries; J. Walton; X. Xiang; Y. Xiong; A.P. Zeng; B.W. Brandt; M.J. Cornell; C.A.M.J.J. van den Hondel; J. Visser; S.G. Oliver; G. Turner

    2009-01-01

    The identification and annotation of protein-coding genes is one of the primary goals of whole-genome sequencing projects, and the accuracy of predicting the primary protein products of gene expression is vital to the interpretation of the available data and the design of downstream functional appli

  12. The 2008 update of the Aspergillus nidulans genome annotation : A community effort

    NARCIS (Netherlands)

    Wortman, Jennifer Russo; Gilsenan, Jane Mabey; Joardar, Vinita; Deegan, Jennifer; Clutterbuck, John; Andersen, Mikael R.; Archer, David; Bencina, Mojca; Braus, Gerhard; Coutinho, Pedro; von Doehren, Hans; Doonan, John; Driessen, Arnold J. M.; Durek, Pawel; Espeso, Eduardo; Fekete, Erzsebet; Flipphi, Michel; Garcia Estrada, Carlos; Geysens, Steven; Goldman, Gustavo; de Groot, Piet W. J.; Hansen, Kim; Harris, Steven D.; Heinekamp, Thorsten; Helmstaedt, Kerstin; Henrissat, Bernard; Hofmann, Gerald; Homan, Tim; Horio, Tetsuya; Horiuchi, Hiroyuki; James, Steve; Jones, Meriel; Karaffa, Levente; Karanyi, Zsolt; Kato, Masashi; Keller, Nancy; Kelly, Diane E.; Kiel, Jan A. K. W.; Kim, Jung-Mi; van der Klei, Ida J.; Klis, Frans M.; Kovalchuk, Andriy; Krasevec, Nada; Kubicek, Christian P.; Liu, Bo; MacCabe, Andrew; Meyer, Vera; Mirabito, Pete; Miskei, Marton; Mos, Magdalena; Mullins, Jonathan; Nelson, David R.; Nielsen, Jens; Oakley, Berl R.; Osmani, Stephen A.; Pakula, Tiina; Paszewski, Andrzej; Paulsen, Ian; Pilsyk, Sebastian; Pocsi, Istvan; Punt, Peter J.; Ram, Arthur F. J.; Ren, Qinghu; Robellet, Xavier; Robson, Geoff; Seiboth, Bernhard; van Solingen, Piet; Specht, Thomas; Sun, Jibin; Taheri-Talesh, Naimeh; Takeshita, Norio; Ussery, Dave; Vankuyk, Patricia A.; Visser, Hans; de Vondervoort, Peter J. I. van; Walton, Jonathan; Xiang, Xin; Xiong, Yi; Zeng, An Ping; Brandt, Bernd W.; Cornell, Michael J.; van den Hondel, Cees A. M. J. J.; Visser, Jacob; Oliver, Stephen G.; Turner, Geoffrey; Kraševec, Nada; Kuyk, Patricia A. van; Döhren, D.H.; van Seilboth, B; de Vries, R.

    2009-01-01

    The identification and annotation of protein-coding genes is one of the primary goals of whole-genome sequencing projects, and the accuracy of predicting the primary protein products of gene expression is vital to the interpretation of the available data and the design of downstream functional appli

  13. The transmission of cytoplasmic genes in Aspergillus nidulans.

    NARCIS (Netherlands)

    Coenen, A.

    1997-01-01

    IntroductionThis manuscript concerns the spread of selfish cytoplasmic genes in the fungus Aspergillus nidulans. A.nidulans is a common soil fungus that grows vegetatively by forming a network (mycelium) of hyphae and reproduces via sexual ascospores and asexual conidiospores. Cytop

  14. Identification of glucose transporters in Aspergillus nidulans.

    Science.gov (United States)

    Dos Reis, Thaila Fernanda; Menino, João Filipe; Bom, Vinícius Leite Pedro; Brown, Neil Andrew; Colabardini, Ana Cristina; Savoldi, Marcela; Goldman, Maria Helena S; Rodrigues, Fernando; Goldman, Gustavo Henrique

    2013-01-01

    To characterize the mechanisms involved in glucose transport, in the filamentous fungus Aspergillus nidulans, we have identified four glucose transporter encoding genes hxtB-E. We evaluated the ability of hxtB-E to functionally complement the Saccharomyces cerevisiae EBY.VW4000 strain that is unable to grow on glucose, fructose, mannose or galactose as single carbon source. In S. cerevisiae HxtB-E were targeted to the plasma membrane. The expression of HxtB, HxtC and HxtE was able to restore growth on glucose, fructose, mannose or galactose, indicating that these transporters accept multiple sugars as a substrate through an energy dependent process. A tenfold excess of unlabeled maltose, galactose, fructose, and mannose were able to inhibit glucose uptake to different levels (50 to 80 %) in these s. cerevisiae complemented strains. Moreover, experiments with cyanide-m-chlorophenylhydrazone (CCCP), strongly suggest that hxtB, -C, and -E mediate glucose transport via active proton symport. The A. nidulans ΔhxtB, ΔhxtC or ΔhxtE null mutants showed ~2.5-fold reduction in the affinity for glucose, while ΔhxtB and -C also showed a 2-fold reduction in the capacity for glucose uptake. The ΔhxtD mutant had a 7.8-fold reduction in affinity, but a 3-fold increase in the capacity for glucose uptake. However, only the ΔhxtB mutant strain showed a detectable decreased rate of glucose consumption at low concentrations and an increased resistance to 2-deoxyglucose. PMID:24282591

  15. Identification of glucose transporters in Aspergillus nidulans.

    Directory of Open Access Journals (Sweden)

    Thaila Fernanda Dos Reis

    Full Text Available To characterize the mechanisms involved in glucose transport, in the filamentous fungus Aspergillus nidulans, we have identified four glucose transporter encoding genes hxtB-E. We evaluated the ability of hxtB-E to functionally complement the Saccharomyces cerevisiae EBY.VW4000 strain that is unable to grow on glucose, fructose, mannose or galactose as single carbon source. In S. cerevisiae HxtB-E were targeted to the plasma membrane. The expression of HxtB, HxtC and HxtE was able to restore growth on glucose, fructose, mannose or galactose, indicating that these transporters accept multiple sugars as a substrate through an energy dependent process. A tenfold excess of unlabeled maltose, galactose, fructose, and mannose were able to inhibit glucose uptake to different levels (50 to 80 % in these s. cerevisiae complemented strains. Moreover, experiments with cyanide-m-chlorophenylhydrazone (CCCP, strongly suggest that hxtB, -C, and -E mediate glucose transport via active proton symport. The A. nidulans ΔhxtB, ΔhxtC or ΔhxtE null mutants showed ~2.5-fold reduction in the affinity for glucose, while ΔhxtB and -C also showed a 2-fold reduction in the capacity for glucose uptake. The ΔhxtD mutant had a 7.8-fold reduction in affinity, but a 3-fold increase in the capacity for glucose uptake. However, only the ΔhxtB mutant strain showed a detectable decreased rate of glucose consumption at low concentrations and an increased resistance to 2-deoxyglucose.

  16. Overexpression of a novel endogenous NADH kinase in Aspergillus nidulans enhances growth

    DEFF Research Database (Denmark)

    Panagiotou, Gianni; Grotkjær, Thomas; Hofmann, Gerald;

    2009-01-01

    The complete genome sequence of the filamentous fungi Aspergillus nidulans has paved the way for fundamental research on this industrially important species. To the best of our knowledge, this is the first time a gene encoding for ATP-dependent NADH kinase (ATP: NADH 2'-phosphotransferase, EC 2...

  17. Identification of developmental regulatory genes in Aspergillus nidulans by overexpression.

    Science.gov (United States)

    Marhoul, J F; Adams, T H

    1995-02-01

    Overexpression of several Aspergillus nidulans developmental regulatory genes has been shown to cause growth inhibition and development at inappropriate times. We set out to identify previously unknown developmental regulators by constructing a nutritionally inducible A. nidulans expression library containing small, random genomic DNA fragments inserted next to the alcA promoter [alcA(p)] in an A. nidulans transformation vector. Among 20,000 transformants containing random alcA(p) genomic DNA fusion constructs, we identified 66 distinct mutant strains in which alcA(p) induction resulted in growth inhibition as well as causing other detectable phenotypic changes. These growth inhibited mutants were divided into 52 FIG (Forced expression Inhibition of Growth) and 14 FAB (Forced expression Activation of brlA) mutants based on whether or not alcA(p) induction resulted in accumulation of mRNA for the developmental regulatory gene brlA. In four FAB mutants, alcA(p) induction not only activated brlA expression but also caused hyphae to differentiate into reduced conidiophores that produced viable spores from the tips as is observed after alcA(p)::brlA induction. Sequence analyses of the DNA fragments under alcA(p) control in three of these four sporulating strains showed that in two cases developmental activation resulted from overexpression of previously uncharacterized genes, whereas in the third strain, the alcA(p) was fused to brlA. The potential uses for this strategy in identifying genes whose overexpression results in specific phenotypic changes like developmental induction are discussed.

  18. Genomic clones of Aspergillus nidulans containing alcA, the structural gene for alcohol dehydrogenase and alcR, a regulatory gene for ethanol metabolism.

    Science.gov (United States)

    Doy, C H; Pateman, J A; Olsen, J E; Kane, H J; Creaser, E H

    1985-04-01

    Our aim was to obtain from Aspergillus nidulans a genomic bank and then clone a region we expected from earlier genetic mapping to contain two closely linked genes, alcA, the structural gene for alcohol dehydrogenase (ADH) and alcR, a positive trans-acting regulatory gene for ethanol metabolism. The expression of alcA is repressed by carbon catabolites. A genomic restriction fragment characteristic of the alcA-alcR region was identified, cloned in pBR322, and used to select from a genomic bank in lambda EMBL3A three overlapping clones covering 24 kb of DNA. Southern genomic analysis of wild-type, alcA and alcR mutants showed that the mutants contained extra DNA at sites near the center of the cloned DNA and are close together, as expected for alcA and alcR. Transcription from the cloned DNA and hybridization with a clone carrying the Saccharomyces cerevisiae gene for ADHI (ADC1) are both confined to the alcA-alcR region. At least one of several species of mature mRNA is about 1 kb, the size required to code for ADH. For all species, carbon catabolite repression overrides control by induction. The overall characteristics of transcription, hybridization to ADC1 and earlier work suggest that alcA consists of a number of exons and/or that the alcA-alcR region represents a cluster of alcA-related genes or sequences.

  19. The Spt-Ada-Gcn5 Acetyltransferase (SAGA complex in Aspergillus nidulans.

    Directory of Open Access Journals (Sweden)

    Paraskevi Georgakopoulos

    Full Text Available A mutation screen in Aspergillus nidulans uncovered mutations in the acdX gene that led to altered repression by acetate, but not by glucose. AcdX of A. nidulans is highly conserved with Spt8p of Saccharomyces cerevisiae, and since Spt8p is a component of the Spt-Ada-Gcn5 Acetyltransferase (SAGA complex, the SAGA complex may have a role in acetate repression in A. nidulans. We used a bioinformatic approach to identify genes encoding most members of the SAGA complex in A. nidulans, and a proteomic analysis to confirm that most protein components identified indeed exist as a complex in A. nidulans. No apparent compositional differences were detected in mycelia cultured in acetate compared to glucose medium. The methods used revealed apparent differences between Yeast and A. nidulans in the deubiquitination (DUB module of the complex, which in S. cerevisiae consists of Sgf11p, Sus1p, and Ubp8p. Although a convincing homologue of S. cerevisiae Ubp8p was identified in the A. nidulans genome, there were no apparent homologues for Sus1p and Sgf11p. In addition, when the SAGA complex was purified from A. nidulans, members of the DUB module were not co-purified with the complex, indicating that functional homologues of Sus1p and Sgf11p were not part of the complex. Thus, deubiquitination of H2B-Ub in stress conditions is likely to be regulated differently in A. nidulans compared to S. cerevisiae.

  20. Onset of carbon catabolite repression in Aspergillus nidulans

    NARCIS (Netherlands)

    Flipphi, M.; Vondervoort, van de P.J.I.; Ruijter, G.J.G.; Visser, J.; Arst Jr., H.N.; Felenbok, B.

    2003-01-01

    The role of hexose phosphorylating enzymes in the signaling of carbon catabolite repression was investigated in the filamentous fungus Aspergillus nidulans. A D-fructose non-utilizing, hexokinase-deficient (hxkA1, formerly designated frA1) strain was utilized to obtain new mutants lacking either glu

  1. Overexpression of two penicillin structural genes in Aspergillus nidulans.

    Science.gov (United States)

    Fernández-Cañón, J M; Peñalva, M A

    1995-01-01

    We have placed two different penicillin structural genes from Aspergillus nidulans, ipnA (encoding isopenicillin N synthetase, IPNS) and acyA (encoding acyl-CoA:6-aminopenicillanic acid acyltransferase, AAT), under the control of the strong alcA promoter [alcA(p)]. Single copies of these transcriptional fusions were targeted to the same chromosomal location and conditions have been worked out which simultaneously allow induction of the alcA(p) and support penicillin biosynthesis. Transcriptional induction of the chimeric genes alcA(p)::ipnA or alcA(p)::acyA(cdna) in the relevant recombinant strains results in 10-fold higher levels of the ipnA or acyA transcripts than those resulting from transcription of the corresponding endogenous genes. This increase causes a 40-fold rise in IPNS activity or a 8-fold rise in AAT activity. Despite this rise in enzyme levels, forced expression of the ipnA gene results in only a modest increase in levels of exported penicillin, whereas forced expression of the acyA gene reduces penicillin production, showing that neither of these enzymes is rate-limiting for penicillin biosynthesis in A. nidulans. A genomic version of the alcA(p)::acyA fusion in which the acyA gene is interrupted by three small introns, is inducible by threonine to a lesser extent (as determined by both acyA mRNA levels and AAT enzyme levels) than the corresponding cDNA version, suggesting that processing of the introns present in the primary transcript may limit acyA expression.

  2. A molecular analysis of L-arabinan degradation in Aspergillus niger and Aspergillus nidulans.

    NARCIS (Netherlands)

    Flipphi, M.J.A.

    1995-01-01

    This thesis describes a molecular study of the genetics ofL-arabinan degradation in Aspergillus niger and Aspergillus nidulans. These saprophytic hyphal fungi produce an extracellular hydrolytic enzyme system to depolymerize the plant cell wall polysaccharideL<

  3. Heterologous expression of the Aspergillus nidulans alcR-alcA system in Aspergillus niger

    NARCIS (Netherlands)

    Nikolaev, I.; Mathieu, M.; Vondervoort, van de P.J.I.; Visser, J.; Felenbok, B.

    2002-01-01

    The inducible and strongly expressed alcA gene encoding alcohol dehydrogenase I from Aspergillus nidulans was transferred together with the activator gene alcR, in the industrial fungus Aspergillus niger. This latter organism does not possess an inducible alc system but has an endogenously constitut

  4. Checkpoint Defects Leading to Premature Mitosis Also Cause Endoreplication of DNA in Aspergillus nidulans

    OpenAIRE

    De Souza, Colin P. C.; Ye, Xiang S.; Osmani, Stephen A.

    1999-01-01

    The G2 DNA damage and slowing of S-phase checkpoints over mitosis function through tyrosine phosphorylation of NIMXcdc2 in Aspergillus nidulans. We demonstrate that breaking these checkpoints leads to a defective premature mitosis followed by dramatic rereplication of genomic DNA. Two additional checkpoint functions, uvsB and uvsD, also cause the rereplication phenotype after their mutation allows premature mitosis in the presence of low concentrations of hydroxyurea. uvsB is shown to encode ...

  5. Purification and properties of beta-galactosidase from Aspergillus nidulans.

    Science.gov (United States)

    Díaz, M; Pedregosa, A M; de Lucas, J R; Torralba, S; Monistrol, I F; Laborda, F

    1996-12-01

    Beta-Galactosidase from mycelial extract of Aspergillus nidulans has been purified by substrate affinity chromatography and used to obtain anti-beta-galactosidase polyclonal antibodies. A. nidulans growing in lactose as carbon source synthesizes one active form of beta-galactosidase which seems to be a multimeric enzyme of 450 kDa composed of monomers with 120 and 97 kDa. Although the enzyme was not released to the culture medium, some enzymatic activity was detected in a cell-wall extract, thus suggesting that it can be an extracellular enzyme. Beta-Galactosidase of A. nidulans is a very unstable enzyme with an optimum pH value of 7.5 and an optimum temperature of 30 degrees C. It was only active against beta-galactoside substrates like lactose and p-nitrophenyl-beta-D-galactoside (PNPG).

  6. Characterization and biotechnological application of recombinant xylanases from Aspergillus nidulans

    NARCIS (Netherlands)

    Maitan-Alfenas, Gabriela P; Oliveira, Mariana B; Nagem, Ronaldo A P; de Vries, Ronald P; Guimarães, Valéria M

    2016-01-01

    Two xylanases from Aspergillus nidulans, XlnB and XlnC, were expressed in Pichia pastoris, purified and characterized. XlnB and XlnC achieved maximal activities at 60°C and pH 7.5 and at 50°C and pH 6.0, respectively. XlnB showed to be very thermostable by maintaining 50% of its original activity af

  7. Identification and characterization of a novel diterpene gene cluster in Aspergillus nidulans.

    Directory of Open Access Journals (Sweden)

    Kirsi Bromann

    Full Text Available Fungal secondary metabolites are a rich source of medically useful compounds due to their pharmaceutical and toxic properties. Sequencing of fungal genomes has revealed numerous secondary metabolite gene clusters, yet products of many of these biosynthetic pathways are unknown since the expression of the clustered genes usually remains silent in normal laboratory conditions. Therefore, to discover new metabolites, it is important to find ways to induce the expression of genes in these otherwise silent biosynthetic clusters. We discovered a novel secondary metabolite in Aspergillus nidulans by predicting a biosynthetic gene cluster with genomic mining. A Zn(II(2Cys(6-type transcription factor, PbcR, was identified, and its role as a pathway-specific activator for the predicted gene cluster was demonstrated. Overexpression of pbcR upregulated the transcription of seven genes in the identified cluster and led to the production of a diterpene compound, which was characterized with GC/MS as ent-pimara-8(14,15-diene. A change in morphology was also observed in the strains overexpressing pbcR. The activation of a cryptic gene cluster by overexpression of its putative Zn(II(2Cys(6-type transcription factor led to discovery of a novel secondary metabolite in Aspergillus nidulans. Quantitative real-time PCR and DNA array analysis allowed us to predict the borders of the biosynthetic gene cluster. Furthermore, we identified a novel fungal pimaradiene cyclase gene as well as genes encoding 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA reductase and a geranylgeranyl pyrophosphate (GGPP synthase. None of these genes have been previously implicated in the biosynthesis of terpenes in Aspergillus nidulans. These results identify the first Aspergillus nidulans diterpene gene cluster and suggest a biosynthetic pathway for ent-pimara-8(14,15-diene.

  8. Identification and Characterization of a Novel Diterpene Gene Cluster in Aspergillus nidulans

    Science.gov (United States)

    Bromann, Kirsi; Toivari, Mervi; Viljanen, Kaarina; Vuoristo, Anu; Ruohonen, Laura; Nakari-Setälä, Tiina

    2012-01-01

    Fungal secondary metabolites are a rich source of medically useful compounds due to their pharmaceutical and toxic properties. Sequencing of fungal genomes has revealed numerous secondary metabolite gene clusters, yet products of many of these biosynthetic pathways are unknown since the expression of the clustered genes usually remains silent in normal laboratory conditions. Therefore, to discover new metabolites, it is important to find ways to induce the expression of genes in these otherwise silent biosynthetic clusters. We discovered a novel secondary metabolite in Aspergillus nidulans by predicting a biosynthetic gene cluster with genomic mining. A Zn(II)2Cys6–type transcription factor, PbcR, was identified, and its role as a pathway-specific activator for the predicted gene cluster was demonstrated. Overexpression of pbcR upregulated the transcription of seven genes in the identified cluster and led to the production of a diterpene compound, which was characterized with GC/MS as ent-pimara-8(14),15-diene. A change in morphology was also observed in the strains overexpressing pbcR. The activation of a cryptic gene cluster by overexpression of its putative Zn(II)2Cys6–type transcription factor led to discovery of a novel secondary metabolite in Aspergillus nidulans. Quantitative real-time PCR and DNA array analysis allowed us to predict the borders of the biosynthetic gene cluster. Furthermore, we identified a novel fungal pimaradiene cyclase gene as well as genes encoding 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase and a geranylgeranyl pyrophosphate (GGPP) synthase. None of these genes have been previously implicated in the biosynthesis of terpenes in Aspergillus nidulans. These results identify the first Aspergillus nidulans diterpene gene cluster and suggest a biosynthetic pathway for ent-pimara-8(14),15-diene. PMID:22506079

  9. Regulation of Development in Aspergillus nidulans and Aspergillus fumigatus

    OpenAIRE

    Yu, Jae-Hyuk

    2010-01-01

    Members of the genus Aspergillus are the most common fungi and all reproduce asexually by forming long chains of conidiospores (or conidia). The impact of various Aspergillus species on humans ranges from beneficial to harmful. For example, several species including Aspergillus oryzae and Aspergillus niger are used in industry for enzyme production and food processing. In contrast, Aspergillus flavus produce the most potent naturally present carcinogen aflatoxins, which contaminate various pl...

  10. Increase in mitotic recombination in diploid cells of Aspergillus nidulans in response to ethidium bromide

    Directory of Open Access Journals (Sweden)

    Tânia C.A. Becker

    2003-01-01

    Full Text Available Ethidium bromide (EB is an intercalating inhibitor of topoisomerase II and its activities are related to chemotherapeutic drugs used in anti-cancer treatments. EB promotes several genotoxic effects in exposed cells by stabilising the DNA-enzyme complex. The recombinagenic potential of EB was evaluated in our in vivo study by the loss of heterozygosity of nutritional markers in diploid Aspergillus nidulans cells through Homozygotization Index (HI. A DNA repair mutation, uvsZ and a chromosome duplication DP (II-I were introduced in the genome of tested cells to obtain a sensitive system for the recombinagenesis detection. EB-treated diploid cells had HI values significantly greater than the control at both concentrations (4.0 x 10-3 and 5.0 x 10-3 mM. Results indicate that the intercalating agent is potentially capable of inducing mitotic crossing-over in diploid A. nidulans cells.

  11. The nucleation of microtubules in Aspergillus nidulans germlings

    Directory of Open Access Journals (Sweden)

    Andrade-Monteiro Cristina de

    1999-01-01

    Full Text Available Microtubules are filaments composed of dimers of alpha- and beta-tubulins, which have a variety of functions in living cells. In fungi, the spindle pole bodies usually have been considered to be microtubule-organizing centers. We used the antimicrotubule drug Benomyl in block/release experiments to depolymerize and repolymerize microtubules in Aspergillus nidulans germlings to learn more about the microtubule nucleation process in this filamentous fungus. Twenty seconds after release from Benomyl short microtubules were formed from several bright (immunofluorescent dots distributed along the germlings, suggesting that microtubule nucleation is randomly distributed in A. nidulans germlings. Since nuclear movement is dependent on microtubules in A. nidulans we analyzed whether mutants defective in nuclear distribution along the growing hyphae (nud mutants have some obvious microtubule defect. Cytoplasmic, astral and spindle microtubules were present and appeared to be normal in all nud mutants. However, significant changes in the percentage of short versus long mitotic spindles were observed in nud mutants. This suggests that some of the nuclei of nud mutants do not reach the late stage of cell division at normal temperatures.

  12. Aspergillus nidulans galactofuranose biosynthesis affects antifungal drug sensitivity.

    Science.gov (United States)

    Alam, Md Kausar; El-Ganiny, Amira M; Afroz, Sharmin; Sanders, David A R; Liu, Juxin; Kaminskyj, Susan G W

    2012-12-01

    The cell wall is essential for fungal survival in natural environments. Many fungal wall carbohydrates are absent from humans, so they are a promising source of antifungal drug targets. Galactofuranose (Galf) is a sugar that decorates certain carbohydrates and lipids. It comprises about 5% of the Aspergillus fumigatus cell wall, and may play a role in systemic aspergillosis. We are studying Aspergillus wall formation in the tractable model system, A. nidulans. Previously we showed single-gene deletions of three sequential A. nidulans Galf biosynthesis proteins each caused similar hyphal morphogenesis defects and 500-fold reduced colony growth and sporulation. Here, we generated ugeA, ugmA and ugtA strains controlled by the alcA(p) or niiA(p) regulatable promoters. For repression and expression, alcA(p)-regulated strains were grown on complete medium with glucose or threonine, whereas niiA(p)-regulated strains were grown on minimal medium with ammonium or nitrate. Expression was assessed by qPCR and colony phenotype. The alcA(p) and niiA(p) strains produced similar effects: colonies resembling wild type for gene expression, and resembling deletion strains for gene repression. Galf immunolocalization using the L10 monoclonal antibody showed that ugmA deletion and repression phenotypes correlated with loss of hyphal wall Galf. None of the gene manipulations affected itraconazole sensitivity, as expected. Deletion of any of ugmA, ugeA, ugtA, their repression by alcA(p) or niiA(p), OR, ugmA overexpression by alcA(p), increased sensitivity to Caspofungin. Strains with alcA(p)-mediated overexpression of ugeA and ugtA had lower caspofungin sensitivity. Galf appears to play an important role in A. nidulans growth and vigor.

  13. Studies on carbon metabolism in wild type and mutants of Aspergillus nidulans

    NARCIS (Netherlands)

    Uitzetter, J.H.A.A.

    1982-01-01

    This thesis deals with carbon metabolism in the lower eukaryote Aspergillus nidulans. This fungus is an attractive organism as a model to study genetics in relation to metabolism in lower eukaryotes.In chapter I the present state of affairs in this field is summarized for A. nidulans and some of the

  14. Systems Analysis Unfolds the Relationship between the Phosphoketolase Pathway and Growth in Aspergillus nidulans

    DEFF Research Database (Denmark)

    Panagiotou, Gianni; Andersen, Mikael Rørdam; Grotkjær, Thomas;

    2008-01-01

    Background: Aspergillus nidulans is an important model organism for studies on fundamental eukaryotic cell biology and on industrial processes due to its close relation to A. niger and A. oryzae. Here we identified the gene coding for a novel metabolic pathway in A. nidulans, namely...

  15. Heterologous expression of the Aspergillus nidulans alcR-alcA system in Aspergillus niger.

    Science.gov (United States)

    Nikolaev, I; Mathieu, M; van de Vondervoort, P; Visser, J; Felenbok, B

    2002-10-01

    The inducible and strongly expressed alcA gene encoding alcohol dehydrogenase I from Aspergillus nidulans was transferred together with the activator gene alcR, in the industrial fungus Aspergillus niger. This latter organism does not possess an inducible alc system but has an endogenously constitutive lowly expressed alcohol dehydrogenase activity. The overall induced expression of the alcA gene was of the same order in both fungi, as monitored by alcA transcription, alcohol dehydrogenase activity and heterologous expression of the reporter enzyme, beta-glucuronidase. However, important differences in the pattern of alcA regulation were observed between the two fungi. A high basal level of alcA transcription was observed in A. niger resulting in a lower ratio of alcA inducibility. This may be due to higher levels of the physiological inducer of the alc regulon, acetaldehyde, from general metabolism in A. niger which differs from that of A. nidulans.

  16. Branching is coordinated with mitosis in growing hyphae of Aspergillus nidulans

    DEFF Research Database (Denmark)

    Dynesen, Jens Østergaard; Nielsen, Jens

    2003-01-01

    Filamentous fungi like Aspergillus nidulans can effectively colonize their surroundings by the formation of new branches along the existing hyphae. While growth conditions, chemical perturbations, and mutations affecting branch formation have received great attention during the last decades, the ...

  17. VelC positively controls sexual development in Aspergillus nidulans.

    Directory of Open Access Journals (Sweden)

    Hee-Soo Park

    Full Text Available Fungal development and secondary metabolism is intimately associated via activities of the fungi-specific velvet family proteins including VeA, VosA, VelB and VelC. Among these, VelC has not been characterized in Aspergillus nidulans. In this study, we characterize the role of VelC in asexual and sexual development in A. nidulans. The velC mRNA specifically accumulates during the early phase of sexual development. The deletion of velC leads to increased number of conidia and reduced production of sexual fruiting bodies (cleistothecia. In the velC deletion mutant, mRNA levels of the brlA, abaA, wetA and vosA genes that control sequential activation of asexual sporulation increase. Overexpression of velC causes increased formation of cleistothecia. These results suggest that VelC functions as a positive regulator of sexual development. VelC is one of the five proteins that physically interact with VosA in yeast two-hybrid and GST pull down analyses. The ΔvelC ΔvosA double mutant produced fewer cleistothecia and behaved similar to the ΔvosA mutant, suggesting that VosA is epistatic to VelC in sexual development, and that VelC might mediate control of sex through interacting with VosA at specific life stages for sexual fruiting.

  18. Fatty acid composition of oil synthesized by Aspergillus nidulans.

    Science.gov (United States)

    Sharma, N D; Mathur, J M; Saxena, B S; Sen, K

    1981-01-01

    The filamentous fungus Aspergillus nidulans Eidam strain 300 was found to be capable of synthesizing 24.9% oil or remarkably low free fatty acidity, in a chemically defined medium with 34% glucose as sole carbon source. although the total content of oil synthesized was less, utilization of the carbon source is better as shown by the high (8.4) fat coefficient. The major component fatty acids of the oil were palmitic, stearic, oleic and linoleic and are influenced by the source of carbon. Palmitoleic acid is present in traces, confirming thereby the general observation that high oil formers produce oil of low hexadecenoic acid content. The relatively high stearic acid content of the oil distinguishes it from those of other microorganisms and resembles the oil produced by certain tropical plants, such as Madhuca latifolia. PMID:7026394

  19. Sequencing of Aspergillus nidulans and comparative analysis with A. fumigatus and A. oryzae.

    Science.gov (United States)

    Galagan, James E; Calvo, Sarah E; Cuomo, Christina; Ma, Li-Jun; Wortman, Jennifer R; Batzoglou, Serafim; Lee, Su-In; Baştürkmen, Meray; Spevak, Christina C; Clutterbuck, John; Kapitonov, Vladimir; Jurka, Jerzy; Scazzocchio, Claudio; Farman, Mark; Butler, Jonathan; Purcell, Seth; Harris, Steve; Braus, Gerhard H; Draht, Oliver; Busch, Silke; D'Enfert, Christophe; Bouchier, Christiane; Goldman, Gustavo H; Bell-Pedersen, Deborah; Griffiths-Jones, Sam; Doonan, John H; Yu, Jaehyuk; Vienken, Kay; Pain, Arnab; Freitag, Michael; Selker, Eric U; Archer, David B; Peñalva, Miguel A; Oakley, Berl R; Momany, Michelle; Tanaka, Toshihiro; Kumagai, Toshitaka; Asai, Kiyoshi; Machida, Masayuki; Nierman, William C; Denning, David W; Caddick, Mark; Hynes, Michael; Paoletti, Mathieu; Fischer, Reinhard; Miller, Bruce; Dyer, Paul; Sachs, Matthew S; Osmani, Stephen A; Birren, Bruce W

    2005-12-22

    The aspergilli comprise a diverse group of filamentous fungi spanning over 200 million years of evolution. Here we report the genome sequence of the model organism Aspergillus nidulans, and a comparative study with Aspergillus fumigatus, a serious human pathogen, and Aspergillus oryzae, used in the production of sake, miso and soy sauce. Our analysis of genome structure provided a quantitative evaluation of forces driving long-term eukaryotic genome evolution. It also led to an experimentally validated model of mating-type locus evolution, suggesting the potential for sexual reproduction in A. fumigatus and A. oryzae. Our analysis of sequence conservation revealed over 5,000 non-coding regions actively conserved across all three species. Within these regions, we identified potential functional elements including a previously uncharacterized TPP riboswitch and motifs suggesting regulation in filamentous fungi by Puf family genes. We further obtained comparative and experimental evidence indicating widespread translational regulation by upstream open reading frames. These results enhance our understanding of these widely studied fungi as well as provide new insight into eukaryotic genome evolution and gene regulation. PMID:16372000

  20. Characterization of the aodA, dnmA, mnSOD and pimA genes in Aspergillus nidulans.

    Science.gov (United States)

    Leiter, Éva; Park, Hee-Soo; Kwon, Nak-Jung; Han, Kap-Hoon; Emri, Tamás; Oláh, Viktor; Mészáros, Ilona; Dienes, Beatrix; Vincze, János; Csernoch, László; Yu, Jae-Hyuk; Pócsi, István

    2016-02-05

    Mitochondria play key roles in cellular energy generation and lifespan of most eukaryotes. To understand the functions of four nuclear-encoded genes predicted to be related to the maintenance of mitochondrial morphology and function in Aspergillus nidulans, systematic characterization was carried out. The deletion and overexpression mutants of aodA, dnmA, mnSOD and pimA encoding alternative oxidase, dynamin related protein, manganese superoxide dismutase and Lon protease, respectively, were generated and examined for their growth, stress tolerances, respiration, autolysis, cell death, sterigmatocystin production, hyphal morphology and size, and mitochondrial superoxide production as well as development. Overall, genetic manipulation of these genes had less effect on cellular physiology and ageing in A. nidulans than that of their homologs in another fungus Podospora anserina with a well-characterized senescence. The observed interspecial phenotypic differences can be explained by the dissimilar intrinsic stabilities of the mitochondrial genomes in A. nidulans and P. anserina. Furthermore, the marginally altered phenotypes observed in A. nidulans mutants indicate the presence of effective compensatory mechanisms for the complex networks of mitochondrial defense and quality control. Importantly, these findings can be useful for developing novel platforms for heterologous protein production, or on new biocontrol and bioremediation technologies based on Aspergillus species.

  1. Human leukocytes kill Aspergillus nidulans by reactive oxygen species-independent mechanisms

    NARCIS (Netherlands)

    Henriet, S.S.V.; Hermans, P.W.M.; Verweij, P.E.; Simonetti, E.R.; Holland, S.M.; Sugui, J.A.; Kwon-Chung, K.J.; Warris, A.

    2011-01-01

    Invasive aspergillosis is a major threat for patients suffering from chronic granulomatous disease (CGD). Although Aspergillus fumigatus is the most commonly encountered Aspergillus species, the presence of A. nidulans appears to be disproportionately high in CGD patients. The purpose of this study

  2. Selection arena in Aspergillus nidulans : early progeny choice in a filamentous fungus = Selectie arena in Aspergillus nidulans : vroege selectie van nakomelingen in een filamenteuse schimmel

    NARCIS (Netherlands)

    Bruggeman, J.

    2003-01-01

    Keywords:selection arena, progeny choice, Aspergillus nidulans , fungus, spores, ascospore, conidiospore, asexual, sexual, fruiting body, cleistothecium, zygote, dikaryon, self-sterility, self-fertility, mutation accumulation, fitness,

  3. Engineering Aspergillus nidulans for heterologous ent-kaurene and gamma-terpinene production.

    Science.gov (United States)

    Bromann, Kirsi; Toivari, Mervi; Viljanen, Kaarina; Ruohonen, Laura; Nakari-Setälä, Tiina

    2016-07-01

    Terpenes are a large and varied group of natural products with a wide array of bioactivities and applications. The chemical production of industrially relevant terpenes can be expensive and time-consuming due to the structural complexity of these compounds. Here, we studied Aspergillus nidulans as a heterologous host for monoterpene and diterpene production. Previously, we identified a novel diterpene gene cluster in A. nidulans and showed that overexpression of the cluster-specific transcription factor (pbcR) led to ent-pimara-8(14),15-diene (PD) production. We report further characterization of the A. nidulans PD synthase gene (pbcA). In A. nidulans, overexpression of pbcA resulted in PD production, while deletion of pbcA abolished PD production. Overexpression of Fusarium fujikuroi ent-kaurene synthase (cps/ks) and Citrus unshiu gamma-terpinene synthase resulted in ent-kaurene and gamma-terpinene production, respectively. A. nidulans is a fungal model organism and a close relative to other industrially relevant Aspergillus species. A. nidulans is a known producer of many secondary metabolites, but its ability to produce heterologous monoterpene and diterpene compounds has not been characterized. Here, we show that A. nidulans is capable of heterologous terpene production and thus has potential as a production host for industrially relevant compounds. The genetic engineering principles reported here could also be applied to other Aspergilli. PMID:27098256

  4. Characterization and biotechnological application of recombinant xylanases from Aspergillus nidulans.

    Science.gov (United States)

    Maitan-Alfenas, Gabriela P; Oliveira, Mariana B; Nagem, Ronaldo A P; de Vries, Ronald P; Guimarães, Valéria M

    2016-10-01

    Two xylanases from Aspergillus nidulans, XlnB and XlnC, were expressed in Pichia pastoris, purified and characterized. XlnB and XlnC achieved maximal activities at 60°C and pH 7.5 and at 50°C and pH 6.0, respectively. XlnB showed to be very thermostable by maintaining 50% of its original activity after 49h incubated at 50°C. XlnB had its highest activity against wheat arabinoxylan while XlnC had the best activity against beechwood xylan. Both enzymes were completely inhibited by SDS and HgCl2. Xylotriose at 1mg/ml also totally inibited XlnB activity. TLC analysis showed that the main product of beechwood xylan hydrolysis by XlnB and XlnC was xylotetraose. An additive effect was shown between XlnB and XlnC and the xylanases of two tested commercial cocktails. Sugarcane bagasse saccharification results showed that these two commercial enzymatic cocktails were able to release more glucose and xylose after supplementation with XlnB and XlnC.

  5. Characterization and biotechnological application of recombinant xylanases from Aspergillus nidulans.

    Science.gov (United States)

    Maitan-Alfenas, Gabriela P; Oliveira, Mariana B; Nagem, Ronaldo A P; de Vries, Ronald P; Guimarães, Valéria M

    2016-10-01

    Two xylanases from Aspergillus nidulans, XlnB and XlnC, were expressed in Pichia pastoris, purified and characterized. XlnB and XlnC achieved maximal activities at 60°C and pH 7.5 and at 50°C and pH 6.0, respectively. XlnB showed to be very thermostable by maintaining 50% of its original activity after 49h incubated at 50°C. XlnB had its highest activity against wheat arabinoxylan while XlnC had the best activity against beechwood xylan. Both enzymes were completely inhibited by SDS and HgCl2. Xylotriose at 1mg/ml also totally inibited XlnB activity. TLC analysis showed that the main product of beechwood xylan hydrolysis by XlnB and XlnC was xylotetraose. An additive effect was shown between XlnB and XlnC and the xylanases of two tested commercial cocktails. Sugarcane bagasse saccharification results showed that these two commercial enzymatic cocktails were able to release more glucose and xylose after supplementation with XlnB and XlnC. PMID:27235731

  6. Functional analysis of alcS, a gene of the alc cluster in Aspergillus nidulans.

    Science.gov (United States)

    Flipphi, Michel; Robellet, Xavier; Dequier, Emmanuel; Leschelle, Xavier; Felenbok, Béatrice; Vélot, Christian

    2006-04-01

    The ethanol utilization pathway (alc system) of Aspergillus nidulans requires two structural genes, alcA and aldA, which encode the two enzymes (alcohol dehydrogenase and aldehyde dehydrogenase, respectively) allowing conversion of ethanol into acetate via acetyldehyde, and a regulatory gene, alcR, encoding the pathway-specific autoregulated transcriptional activator. The alcR and alcA genes are clustered with three other genes that are also positively regulated by alcR, although they are dispensable for growth on ethanol. In this study, we characterized alcS, the most abundantly transcribed of these three genes. alcS is strictly co-regulated with alcA, and encodes a 262-amino acid protein. Sequence comparison with protein databases detected a putative conserved domain that is characteristic of the novel GPR1/FUN34/YaaH membrane protein family. It was shown that the AlcS protein is located in the plasma membrane. Deletion or overexpression of alcS did not result in any obvious phenotype. In particular, AlcS does not appear to be essential for the transport of ethanol, acetaldehyde or acetate. Basic Local Alignment Search Tool analysis against the A. nidulans genome led to the identification of two novel ethanol- and ethylacetate-induced genes encoding other members of the GPR1/FUN34/YaaH family, AN5226 and AN8390.

  7. Identification of the augmin complex in the filamentous fungus Aspergillus nidulans.

    Directory of Open Access Journals (Sweden)

    Tomoya Edzuka

    Full Text Available Augmin is a protein complex that binds to spindle microtubules (MTs, recruits the potent MT nucleator, γ-tubulin, and thereby promotes the centrosome-independent MT generation within mitotic and meiotic spindles. Augmin is essential for acentrosomal spindle assembly, which is commonly observed during mitosis in plants and meiosis in female animals. In many animal somatic cells that possess centrosomes, the centrosome- and augmin-dependent mechanisms work cooperatively for efficient spindle assembly and cytokinesis. Yeasts have lost the augmin genes during evolution. It is hypothesized that their robust MT nucleation from the spindle pole body (SPB, the centrosome-equivalent structure in fungi, compensates for the lack of augmin. Intriguingly, however, a gene homologous to an augmin subunit (Aug6/AUGF has been found in the genome of filamentous fungi, which has the SPB as a robust MT nucleation centre. Here, we aimed to clarify if the augmin complex is present in filamentous fungi and to identify its role in mitosis. By analysing the Aug6-like gene in the filamentous fungus Aspergillus nidulans, we found that it forms a large complex with several other proteins that share weak but significant homology to known augmin subunits. In A. nidulans, augmin was enriched at the SPB and also associated with spindle MTs during mitosis. However, the augmin gene disruptants did not exhibit growth defects under normal, checkpoint-deficient, or MT-destabilised conditions. Moreover, we obtained no evidence that A. nidulans augmin plays a role in γ-tubulin recruitment or in mitotic cell division. Our study uncovered the conservation of the augmin complex in the fungal species, and further suggests that augmin has several functions, besides mitotic spindle MT nucleation, that are yet to be identified.

  8. Antisense silencing of the creA gene in Aspergillus nidulans

    DEFF Research Database (Denmark)

    Bautista, L. F.; Aleksenko, Alexei Y.; Hentzer, Morten;

    2000-01-01

    Antisense expression of a portion of the gene encoding the major carbon catabolite repressor CREA in Aspergillus nidulans resulted in a substantial increase in the levels of glucose-repressible enzymes, both endogenous and heterologous, in the presence of glucose. The derepression effect was appr......Antisense expression of a portion of the gene encoding the major carbon catabolite repressor CREA in Aspergillus nidulans resulted in a substantial increase in the levels of glucose-repressible enzymes, both endogenous and heterologous, in the presence of glucose. The derepression effect...

  9. Requirement of Monooxygenase-Mediated Steps for Sterigmatocystin Biosynthesis by Aspergillus nidulans

    OpenAIRE

    Keller, Nancy P.; Watanabe, Coran M. H.; Kelkar, Hemant S.; Adams, Thomas H; Townsend, Craig A.

    2000-01-01

    Sterigmatocystin (ST) and aflatoxin B1 (AFB1) are two polyketide-derived Aspergillus mycotoxins synthesized by functionally identical sets of enzymes. ST, the compound produced by Aspergillus nidulans, is a late intermediate in the AFB1 pathway of A. parasiticus and A. flavus. Previous biochemical studies predicted that five oxygenase steps are required for the formation of ST. A 60-kb ST gene cluster in A. nidulans contains five genes, stcB, stcF, stcL, stcS, and stcW, encoding putative mono...

  10. SAGA complex components and acetate repression in Aspergillus nidulans.

    Science.gov (United States)

    Georgakopoulos, Paraskevi; Lockington, Robin A; Kelly, Joan M

    2012-11-01

    Alongside the well-established carbon catabolite repression by glucose and other sugars, acetate causes repression in Aspergillus nidulans. Mutations in creA, encoding the transcriptional repressor involved in glucose repression, also affect acetate repression, but mutations in creB or creC, encoding components of a deubiquitination system, do not. To understand the effects of acetate, we used a mutational screen that was similar to screens that uncovered mutations in creA, creB, and creC, except that glucose was replaced by acetate to identify mutations that were affected for repression by acetate but not by glucose. We uncovered mutations in acdX, homologous to the yeast SAGA component gene SPT8, which in growth tests showed derepression for acetate repression but not for glucose repression. We also made mutations in sptC, homologous to the yeast SAGA component gene SPT3, which showed a similar phenotype. We found that acetate repression is complex, and analysis of facA mutations (lacking acetyl CoA synthetase) indicates that acetate metabolism is required for repression of some systems (proline metabolism) but not for others (acetamide metabolism). Although plate tests indicated that acdX- and sptC-null mutations led to derepressed alcohol dehydrogenase activity, reverse-transcription quantitative real-time polymerase chain reaction showed no derepression of alcA or aldA but rather elevated induced levels. Our results indicate that acetate repression is due to repression via CreA together with metabolic changes rather than due to an independent regulatory control mechanism.

  11. DNA-mediated transformation of the filamentous fungus Aspergillus nidulans.

    OpenAIRE

    Wernars, K.

    1986-01-01

    Although transformation of S.   cerevisiae and N.crassa already could be achieved at the end of the seventies, positive results for A.nidulans had to await the isolation of useful selection markers. As soon as cloned fungal genes of homologous ( amd S, trp C and arg B from A.nidulans ) and heterologous ( pyr 4 from N.crassa ) origin became available transformation procedures for A.nidulans were developed (Ballance et al. 1983; Tilburn et al. 1983; Yelton et al. 1984; John and Pederby 1984). T...

  12. Developmental characterization and chromosomal mapping of the 5-azacytidine-sensitive fluF locus of Aspergillus nidulans.

    OpenAIRE

    Tamame, M; Antequera, F; Santos, E.

    1988-01-01

    In Aspergillus nidulans, a fungus that possesses negligible, if any, levels of methylation in its genome, low concentrations of 5-azacytidine (5-AC) convert a high percentage of the cell population to fluffy phenotypic variants through a heritable modification of a single nuclear gene (M. Tamame, F. Antequera, J. R. Villanueva, and T. Santos, Mol. Cell. Biol. 3:2287-2297, 1983). This new 5-AC-altered locus, designated here fluF1, was mapped as the closest marker to the centromere that has bee...

  13. Male and female roles in crosses of Aspergillus nidulans as revealed by vegetatively incompatible parents

    NARCIS (Netherlands)

    Bruggeman, I.M.; Debets, A.J.M.; Swart, K.; Hoekstra, R.F.

    2003-01-01

    To resolve the role of male and female nuclei and mitochondria in cleistothecium formation in the model organism Aspergillus nidulans, we analysed the genetic constituents of cleistothecia, from crosses between vegetatively compatible and incompatible parents. We used markers that enabled us to dete

  14. Screening of Aspergillus nidulans metabolites from habitat mimicking media using LC-DAD-TOFMS system

    DEFF Research Database (Denmark)

    Klitgaard, Andreas; Holm, Dorte Koefoed; Frisvad, Jens Christian;

    2012-01-01

    Fungi are a valuable source of metabolites and other bioactive compounds. These compounds are essential for human society, and it is estimated that around 49% of the drugs used to treat cancer are natural products or derived therefrom. Six different wild types of Aspergillus nidulans have been...

  15. The regulation of phosphoenolpyruvate carboxykinase and the NADP-linked malic enzyme in Aspergillus nidulans.

    Science.gov (United States)

    Kelly, J M; Hynes, M J

    1981-04-01

    It has previously been suggested that the synthesis of phosphoenolpyruvate carboxykinase (EC 4.1.1.32) in Aspergillus nidulans is regulated by a repression-derepression mechanism involving a glycolytic intermediate, and not by induction. Results obtained using compounds that enter the tricarboxylic acid cycle via 2-oxoglutarate, and that can supply both a carbon and a nitrogen source for A. nidulans, suggest it is more likely that the synthesis of phosphoenolpyruvate carboxykinase is inducible, and only weakly regulated by carbon catabolite repression. a similar study of the regulation of the NADP-linked malic enzyme (EC 1.1.1.40) indicates that it too may be inducible.

  16. Characterization of the AN6448 cluster in Aspergillus nidulans

    DEFF Research Database (Denmark)

    Nielsen, Jakob Blæsbjerg; Klejnstrup, Marie Louise; Khorsand-Jamal, Paiman;

    2012-01-01

    With the aim of mapping the polyketome of A. nidulans we have made a library of strains, which individually overexpress PKS genes from an ectopic locus. A screen of this collection on different media demonstrated that AN6448 leads to production of 3-MOA. An inspection of the DNA sequence surround...

  17. Gβ-like CpcB plays a crucial role for growth and development of Aspergillus nidulans and Aspergillus fumigatus.

    Directory of Open Access Journals (Sweden)

    Qing Kong

    Full Text Available Growth, development, virulence and secondary metabolism in fungi are governed by heterotrimeric G proteins (G proteins. A Gβ-like protein called Gib2 has been shown to function as an atypical Gβ in Gpa1-cAMP signaling in Cryptococcus neoformans. We found that the previously reported CpcB (cross pathway control B protein is the ortholog of Gib2 in Aspergillus nidulans and Aspergillus fumigatus. In this report, we further characterize the roles of CpcB in governing growth, development and toxigenesis in the two aspergilli. The deletion of cpcB results in severely impaired cellular growth, delayed spore germination, and defective asexual sporulation (conidiation in both aspergilli. Moreover, CpcB is necessary for proper expression of the key developmental activator brlA during initiation and progression of conidiation in A. nidulans and A. fumigatus. Somewhat in accordance with the previous study, the absence of cpcB results in the formation of fewer, but not micro-, cleistothecia in A. nidulans in the presence of wild type veA, an essential activator of sexual development. However, the cpcB deletion mutant cleistothecia contain no ascospores, validating that CpcB is required for progression and completion of sexual fruiting including ascosporogenesis. Furthermore, unlike the canonical GβSfaD, CpcB is not needed for the biosynthesis of the mycotoxin sterigmatocystin (ST as the cpcB null mutant produced reduced amount of ST with unaltered STC gene expression. However, in A. fumigatus, the deletion of cpcB results in the blockage of gliotoxin (GT production. Further genetic analyses in A. nidulans indicate that CpcB may play a central role in vegetative growth, which might be independent of FadA- and GanB-mediated signaling. A speculative model summarizing the roles of CpcB in conjunction with SfaD in A. nidulans is presented.

  18. Aspergillus nidulans protein kinase A plays an important role in cellulase production

    OpenAIRE

    de Assis, Leandro José; Ries, Laure Nicolas Annick; Savoldi, Marcela; dos Reis, Thaila Fernanda; Brown, Neil Andrew; Goldman, Gustavo Henrique

    2015-01-01

    Background The production of bioethanol from lignocellulosic feedstocks is dependent on lignocellulosic biomass degradation by hydrolytic enzymes. The main component of lignocellulose is cellulose and different types of organisms are able to secrete cellulases. The filamentous fungus Aspergillus nidulans serves as a model organism to study cellulase production and the available tools allow exploring more in depth the mechanisms governing cellulase production and carbon catabolite repression. ...

  19. Molecular genetic analysis reveals that a nonribosomal peptide synthetase-like (NRPS-like) gene in Aspergillus nidulans is responsible for microperfuranone biosynthesis.

    Science.gov (United States)

    Yeh, Hsu-Hua; Chiang, Yi-Ming; Entwistle, Ruth; Ahuja, Manmeet; Lee, Kuan-Han; Bruno, Kenneth S; Wu, Tung-Kung; Oakley, Berl R; Wang, Clay C C

    2012-11-01

    Genome sequencing of Aspergillus species including Aspergillus nidulans has revealed that there are far more secondary metabolite biosynthetic gene clusters than secondary metabolites isolated from these organisms. This implies that these organisms can produce additional secondary metabolites, which have not yet been elucidated. The A. nidulans genome contains 12 nonribosomal peptide synthetase (NRPS), one hybrid polyketide synthase/NRPS, and 14 NRPS-like genes. The only NRPS-like gene in A. nidulans with a known product is tdiA, which is involved in terrequinone A biosynthesis. To attempt to identify the products of these NRPS-like genes, we replaced the native promoters of the NRPS-like genes with the inducible alcohol dehydrogenase (alcA) promoter. Our results demonstrated that induction of the single NRPS-like gene AN3396.4 led to the enhanced production of microperfuranone. Furthermore, heterologous expression of AN3396.4 in Aspergillus niger confirmed that only one NRPS-like gene, AN3396.4, is necessary for the production of microperfuranone.

  20. Physiological characterisation of recombinant Aspergillus nidulans strains with different creA genotypes expressing A-oryzae alpha-amylase

    DEFF Research Database (Denmark)

    Agger, Teit; Petersen, J.B.; O'Connor, S.M.;

    2002-01-01

    The physiology of three strains of Aspergillus nidulans was examined-a creA deletion strain, a wild type creA genotype and a strain containing extra copies of the creA gene, all producing Aspergillus oryzae alpha-amylase. The strains were cultured in batch and continuous cultivations and the...

  1. Genotoxicity of the cyclo-oxygenase-inhibitor sulindac sulfide in the filamentous fungus Aspergillus nidulans Genotoxicidade de sulfeto de sulindaco em Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Claudinéia Conationi da Silva Franco

    2007-09-01

    Full Text Available Sulindac sulfide is a non-steroidal anti-inflammatory drug (NSAID with chemopreventive effect on human cancer cells. Due to the involvement of the somatic recombination in the carcinogenic process, sulindac sulfide's recombinogenic potential was evaluated by the Homozygotization Index (HI in the filamentous fungus Aspergillus nidulans. The drug's recombinogenic potential was evaluated by its capacity to induce homozygosis of recessive genes from heterozygous diploid cells. Sulindac sulfide at 175 and 350 µM concentrations induced mitotic recombination in A. nidulans diploid cells, with HI values for genetic markers higher than 2.0, and significantly different from control HI values. The recombinogenic effect of NSAID was related to the induction of DNA strand breaks and cell cycle alterations. Sulindac sulfide's carcinogenic potential was also discussed.Sulfeto de sulindaco é um antiinflamatório não-esteroidal com efeitos quimiopreventivos em cânceres humanos. O presente estudo teve como objetivo avaliar o potencial recombinagênico do sulfeto de sulindaco em células diplóides de Aspergillus nidulans. O efeito recombinagênico da droga foi demonstrado através da homozigotização de genes recessivos, previamente presentes em heterozigose. Os valores de HI (Índice de Homozigotização para diferentes marcadores genéticos apresentaram-se maiores do que 2,0 e significativamente diferentes dos valores obtidos em sulfeto de sulindaco ausência da droga (controle. O potencial recombinagênico do sulfeto de sulindaco foi associado à indução de quebras na molécula do DNA e a alterações no ciclo celular. O potencial carcinogênico do sulfeto de sulindaco foi discutido no presente trabalho.

  2. Mechanism of Sterigmatocystin Biosynthesis Regulation by pH in Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Francisco Delgado-Virgen

    2009-12-01

    Full Text Available External pH constitutes one of the most important environmental factors that control growth, metabolism and differentiation in microorganisms, including fungi. We have analyzed the effect of external pH on sterigmatocystin biosynthesis in Aspergillus nidulans. It was observed in repeated experiments that alkaline pH, in opposition to acid pH, increased sterigmatocystin production and the transcript levels of aflR, the master gene that regulates expression of the sterigmatocystin cluster in A. nidulans. It is known that pH effects in fungi operate mostly through the Pal/Pac signaling pathway, originally described in Aspergillus nidulans. Accordingly, we studied the role of this signaling pathway in ST biosynthesis. It was observed that aflR transcript levels were increased in the "alkalinity mimicking" mutant pacCc14 and were minimal in the "acidity mimicking" mutant palA1. No sterigmatocystin was produced by palA1 or pacC- mutants at neither acid or alkaline pH of incubation. Finally, fluG and flbA, genes known to regulate both conidiation and sterigmatocystin synthesis upstream in the regulatory cascade, were up-regulated at alkaline pH.

  3. A combined genetic and multi medium approach revels new secondary metabolites in Aspergillus nidulans

    DEFF Research Database (Denmark)

    Klejnstrup, Marie Louise; Nielsen, Morten Thrane; Frisvad, Jens Christian;

    Secondary metabolites are a diverse group of metabolites which serve as important natural sources of drugs for treating diseases. The availability of full genome sequences of several filamentous fungi has revealed a large genetic potential for production of secondary metabolites...... that are not observed under standard laboratory conditions. Genetic approaches have proven a fruitfull strategy towards the production and identification of these unknown metabolites. Examples include deletion of the cclA1 and laeA2 genes in A. nidulans which affects the expression of secondary metabolites including...... monodictyphenone and terrequinone A respectively. We have deleted the cclA gene in A. nidulans and grown the mutants on several complex media to provoke the production of secondary metabolites. This resulted in the production of several metabolites not previously reported from A. nidulans. Some of these have been...

  4. Application of a new dual localization-affinity purification tag reveals novel aspects of protein kinase biology in Aspergillus nidulans.

    Directory of Open Access Journals (Sweden)

    Colin P De Souza

    Full Text Available Filamentous fungi occupy critical environmental niches and have numerous beneficial industrial applications but devastating effects as pathogens and agents of food spoilage. As regulators of essentially all biological processes protein kinases have been intensively studied but how they regulate the often unique biology of filamentous fungi is not completely understood. Significant understanding of filamentous fungal biology has come from the study of the model organism Aspergillus nidulans using a combination of molecular genetics, biochemistry, cell biology and genomic approaches. Here we describe dual localization-affinity purification (DLAP tags enabling endogenous N or C-terminal protein tagging for localization and biochemical studies in A. nidulans. To establish DLAP tag utility we endogenously tagged 17 protein kinases for analysis by live cell imaging and affinity purification. Proteomic analysis of purifications by mass spectrometry confirmed association of the CotA and NimXCdk1 kinases with known binding partners and verified a predicted interaction of the SldABub1/R1 spindle assembly checkpoint kinase with SldBBub3. We demonstrate that the single TOR kinase of A. nidulans locates to vacuoles and vesicles, suggesting that the function of endomembranes as major TOR cellular hubs is conserved in filamentous fungi. Comparative analysis revealed 7 kinases with mitotic specific locations including An-Cdc7 which unexpectedly located to mitotic spindle pole bodies (SPBs, the first such localization described for this family of DNA replication kinases. We show that the SepH septation kinase locates to SPBs specifically in the basal region of apical cells in a biphasic manner during mitosis and again during septation. This results in gradients of SepH between G1 SPBs which shift along hyphae as each septum forms. We propose that SepH regulates the septation initiation network (SIN specifically at SPBs in the basal region of G1 cells and that

  5. Developmental characterization and chromosomal mapping of the 5-azacytidine-sensitive fluF locus of Aspergillus nidulans.

    Science.gov (United States)

    Tamame, M; Antequera, F; Santos, E

    1988-01-01

    In Aspergillus nidulans, a fungus that possesses negligible, if any, levels of methylation in its genome, low concentrations of 5-azacytidine (5-AC) convert a high percentage of the cell population to fluffy phenotypic variants through a heritable modification of a single nuclear gene (M. Tamame, F. Antequera, J. R. Villanueva, and T. Santos, Mol. Cell. Biol. 3:2287-2297, 1983). This new 5-AC-altered locus, designated here fluF1, was mapped as the closest marker to the centromere that has been identified so far on the right arm of chromosome VIII. Of all mutagens tested, only 5-AC induced the fluffy phenotype with a significant frequency. Furthermore, we determined that the wild-type, dominant allele of the fluF gene was primarily accessible to modification by 5-AC at the initial stages of fungal vegetative growth. These results indicated that 5-AC does not act through random mutagenic action but, rather, that fluF constitutes a specific target for this drug during a well-defined period of fungal development. Alteration of fluF by 5-AC resulted in a dramatic modification of the developmental program of A. nidulans. The resulting fluffy clones were characterized by massive, uncontrolled proliferation of undifferentiated hyphae, a drastic delay in the onset of asexual differentiation (conidiation), and colonies with an invasive nature. These features are reminiscent of the malignant properties of tumor cells. We propose that the locus fluF plays a primary role in the control of cell proliferation in A. nidulans and that its alteration by 5-AC produces pleiotropic modifications of the developmental program of this fungus. Images PMID:2463470

  6. Genetic evidence for a microtubule-capture mechanism during polarised growth of Aspergillus nidulans.

    Science.gov (United States)

    Manck, Raphael; Ishitsuka, Yuji; Herrero, Saturnino; Takeshita, Norio; Nienhaus, G Ulrich; Fischer, Reinhard

    2015-10-01

    The cellular switch from symmetry to polarity in eukaryotes depends on the microtubule (MT) and actin cytoskeletons. In fungi such as Schizosaccharomyces pombe or Aspergillus nidulans, the MT cytoskeleton determines the sites of actin polymerization through cortical cell-end marker proteins. Here we describe A. nidulans MT guidance protein A (MigA) as the first ortholog of the karyogamy protein Kar9 from Saccharomyces cerevisiae in filamentous fungi. A. nidulans MigA interacts with the cortical ApsA protein and is involved in spindle positioning during mitosis. MigA is also associated with septal and nuclear MT organizing centers (MTOCs). Super-resolution photoactivated localization microscopy (PALM) analyses revealed that MigA is recruited to assembling and retracting MT plus ends in an EbA-dependent manner. MigA is required for MT convergence in hyphal tips and plays a role in correct localization of the cell-end markers TeaA and TeaR. In addition, MigA interacts with a class-V myosin, suggesting that an active mechanism exists to capture MTs and to pull the ends along actin filaments. Hence, the organization of MTs and actin depend on each other, and positive feedback loops ensure robust polar growth. PMID:26272919

  7. A glucose-derepressed promoter for expression of heterologous products in the filamentous fungus Aspergillus nidulans.

    Science.gov (United States)

    Hintz, W E; Lagosky, P A

    1993-07-01

    We describe a putative binding sequence (GCGGGGC) for the glucose-responsive repressor protein CreA at two positions upstream of the transcription start site of the alcohol dehydrogenase I (alcA) gene of Aspergillus nidulans. To positively identify the putative binding sites as CreA-specific, the GCGGGGC blocks were mutated at five internal nucleotide positions to GTACTAC and reintroduced into the wild type alcA promoter driving expression of the endogenous alcohol dehydrogenase I gene. This CreA-binding site variant was then transformed into an AlcR constitutive A. nidulans host strain (T2625) and growth was monitored in the presence of the non-metabolized glucose analogue, 2-deoxyglucose. Positive transformants were selected by their ability to grow using ethanol as a carbon source in the presence of 2-deoxyglucose. Similar CreA binding site variant alcA promoters should permit the alcA-driven expression of heterologous genes in A. nidulans in the presence of glucose, the preferred carbon source for biomass accumulation and provides a model for controlling carbon-catabolite regulated expression in other expression systems.

  8. A time course analysis of the extracellular proteome of Aspergillus nidulans growing on sorghum stover

    Directory of Open Access Journals (Sweden)

    Saykhedkar Sayali

    2012-07-01

    Full Text Available Abstract Background Fungi are important players in the turnover of plant biomass because they produce a broad range of degradative enzymes. Aspergillus nidulans, a well-studied saprophyte and close homologue to industrially important species such as A. niger and A. oryzae, was selected for this study. Results A. nidulans was grown on sorghum stover under solid-state culture conditions for 1, 2, 3, 5, 7 and 14 days. Based on analysis of chitin content, A. nidulans grew to be 4-5% of the total biomass in the culture after 2 days and then maintained a steady state of 4% of the total biomass for the next 12 days. A hyphal mat developed on the surface of the sorghum by day one and as seen by scanning electron microscopy the hyphae enmeshed the sorghum particles by day 5. After 14 days hyphae had penetrated the entire sorghum slurry. Analysis (1-D PAGE LC-MS/MS of the secretome of A. nidulans, and analysis of the breakdown products from the sorghum stover showed a wide range of enzymes secreted. A total of 294 extracellular proteins were identified with hemicellulases, cellulases, polygalacturonases, chitinases, esterases and lipases predominating the secretome. Time course analysis revealed a total of 196, 166, 172 and 182 proteins on day 1, 3, 7 and 14 respectively. The fungus used 20% of the xylan and cellulose by day 7 and 30% by day 14. Cellobiose dehydrogenase, feruloyl esterases, and CAZy family 61 endoglucanases, all of which are thought to reduce the recalcitrance of biomass to hydrolysis, were found in high abundance. Conclusions Our results show that A. nidulans secretes a wide array of enzymes to degrade the major polysaccharides and lipids (but probably not lignin by 1 day of growth on sorghum. The data suggests simultaneous breakdown of hemicellulose, cellulose and pectin. Despite secretion of most of the enzymes on day 1, changes in the relative abundances of enzymes over the time course indicates that the set of enzymes

  9. Screening of medicinal plants for induction of somatic segregation activity in Aspergillus nidulans.

    Science.gov (United States)

    Ramos Ruiz, A; De la Torre, R A; Alonso, N; Villaescusa, A; Betancourt, J; Vizoso, A

    1996-07-01

    Knowledge about mutagenic properties of plants commonly used in traditional medicine is limited. A screening for genotoxic activity was carried out in aqueous or alcoholic extracts prepared from 13 medicinal plants widely used as folk medicine in Cuba: Lepidium virginicum L. (Brassicaceae): Plantago major L. and Plantago lanceolata L. (Plantaginaceae); Ortosiphon aristatus Blume, Mentha x piperita L., Melissa officinalis L. and Plectranthus amboinicus (Lour.) Spreng. (Lamiaceae); Cymbopogon citratus (DC.) Stapf (Poaceae); Passiflora incarnata L. (Passifloraceae); Zingiber officinale Roscoe (Zingiberaceae); Piper auritum HBK. (Piperaceae); Schinus terebinthifolius Raddi (Anacardeaceae) and Momordica charantia L. (Cucurbitaceae). A plate incorporation assay with Aspergillus nidulans was employed, allowing detection of somatic segregation as a result of mitotic crossing-over, chromosome malsegregation or clastogenic effects. Aspergillus nidulans D-30, a well-marked strain carrying four recessive mutations for conidial color in heterozygosity, which permitted the direct visual detection of segregants, was used throughout this study. As a result, only in the aqueous extract of one of the plants screened (Momordica charantia) a statistical significant increase in the frequency of segregant sectors per colony was observed, and consequently, a genotoxic effect is postulated.

  10. Screening of medicinal plants for induction of somatic segregation activity in Aspergillus nidulans.

    Science.gov (United States)

    Ramos Ruiz, A; De la Torre, R A; Alonso, N; Villaescusa, A; Betancourt, J; Vizoso, A

    1996-07-01

    Knowledge about mutagenic properties of plants commonly used in traditional medicine is limited. A screening for genotoxic activity was carried out in aqueous or alcoholic extracts prepared from 13 medicinal plants widely used as folk medicine in Cuba: Lepidium virginicum L. (Brassicaceae): Plantago major L. and Plantago lanceolata L. (Plantaginaceae); Ortosiphon aristatus Blume, Mentha x piperita L., Melissa officinalis L. and Plectranthus amboinicus (Lour.) Spreng. (Lamiaceae); Cymbopogon citratus (DC.) Stapf (Poaceae); Passiflora incarnata L. (Passifloraceae); Zingiber officinale Roscoe (Zingiberaceae); Piper auritum HBK. (Piperaceae); Schinus terebinthifolius Raddi (Anacardeaceae) and Momordica charantia L. (Cucurbitaceae). A plate incorporation assay with Aspergillus nidulans was employed, allowing detection of somatic segregation as a result of mitotic crossing-over, chromosome malsegregation or clastogenic effects. Aspergillus nidulans D-30, a well-marked strain carrying four recessive mutations for conidial color in heterozygosity, which permitted the direct visual detection of segregants, was used throughout this study. As a result, only in the aqueous extract of one of the plants screened (Momordica charantia) a statistical significant increase in the frequency of segregant sectors per colony was observed, and consequently, a genotoxic effect is postulated. PMID:8771452

  11. The effect of CreA in glucose and xylose catabolism in Aspergillus nidulans

    DEFF Research Database (Denmark)

    Prathumpai, Wai; Mcintyre, Mhairi; Nielsen, Jens

    2004-01-01

    The catabolism of glucose and xylose was studied in a wild type and creA deleted (carbon catabolite de-repressed) strain of Aspergillus nidulans. Both strains were cultivated in bioreactors with either glucose or xylose as the sole carbon source, or in the presence of both sugars. In the cultivat......The catabolism of glucose and xylose was studied in a wild type and creA deleted (carbon catabolite de-repressed) strain of Aspergillus nidulans. Both strains were cultivated in bioreactors with either glucose or xylose as the sole carbon source, or in the presence of both sugars...... of key enzymes in the xylose utilisation pathway revealed that xylose metabolism was occurring in the creA deleted strain, even at high glucose concentrations. Conversely, in the wild type strain, activities of the key enzymes for xylose metabolism increased only when the effects of glucose repression...... had been relieved. Xylose was both a repressor and an inducer of xylanases at the same time. The creA mutation seemed to have pleiotropic effects on carbohydratases and carbon catabolism....

  12. The Aspergillus nidulans amdS gene as a marker for the identification of multicopy T-DNA integration events in Agrobacterium-mediated transformation of Aspergillus awamori

    NARCIS (Netherlands)

    Michielse, C.B.; Ram, A.F.J.; Hondel, C.A.M.J.J. van den

    2004-01-01

    The Aspergillus nidulans amdS selection marker was used for the identification of multicopy T-DNA insertions in Agrobacterium-mediated transformation of Asp. awamori. The selection of transformants on agar plates containing acetamide as sole nitrogen source and hygromycin resulted in a six-fold decr

  13. Molecular genetic analysis reveals that a nonribosomal peptide synthetase-like (NRPS-like) gene in Aspergillus nidulans is responsible for microperfuranone biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, Hsu-Hua; Chiang, Yi Ming; Entwistle, Ruth; Ahuja, Mammeet; Lee, Kuan-Han; Bruno, Kenneth S.; Wu, Tung-Kung; Oakley, Berl R.; Wang, Clay C.

    2012-04-10

    Genome sequencing of Aspergillus species including A. nidulans has revealed that there are far more secondary metabolite biosynthetic gene clusters than secondary metabolites isolated from these organisms. This implies that these organisms can produce additional secondary metabolites have not yet been elucidated. The A. nidulans genome contains twelve nonribosomal peptide synthetase (NRPS), one hybrid polyketide synthase/nonribosomal peptide synthetase (PKS/NRPS), and fourteen NRPS-like genes. The only NRPS-like gene in A. nidulans with a known product is tdiA which is involved in terrequinone A biosynthesis. To attempt to identify the products of these NRPS-like genes, we replaced the native promoters of the NRPS-like genes with the inducible alcohol dehydrogenase (alcA) promoter. Our results demonstrated that induction of the single NRPS-like gene AN3396.4 led to the enhanced production of microperfuranone. Furthermore, heterologous expression of AN3396.4 in A. niger confirmed that only one NRPS-like gene, AN3396.4, is necessary for the production of microperfuranone.

  14. The Aspergillus nidulans alcA promoter drives tightly regulated conditional gene expression in Aspergillus fumigatus permitting validation of essential genes in this human pathogen.

    Science.gov (United States)

    Romero, Beatriz; Turner, Geoffrey; Olivas, Israel; Laborda, Fernando; De Lucas, J Ramón

    2003-11-01

    Aspergillus fumigatus causes invasive aspergillosis, a mycosis that is usually fatal in immunocompromised patients. Functional genomics in this fungus will aid the discovery of novel antifungal drugs to treat invasive aspergillosis. However, there is still a need for appropriate molecular genetic tools to facilitate such functional studies. Here, we describe the use of a conditional gene expression system allowing the identification of novel therapeutic targets through validation of essential genes in A. fumigatus. This system is based on the capacity of the Aspergillus nidulans alcA promoter (alcA(p)) to tightly regulate gene expression in this fungus. Conditionally regulated gene expression in A. fumigatus was demonstrated by transcriptional and phenotypic analyses of strains expressing a nuclear migration gene with a terminal phenotype, the A. fumigatus nudC gene, under control of this promoter. This conditional expression system, the first one described in A. fumigatus, will also be useful for investigating the function of essential genes by altering the threonine/glucose ratio in the growth medium.

  15. Aspergillus nidulans cell wall composition and function change in response to hosting several Aspergillus fumigatus UDP-galactopyranose mutase activity mutants.

    Directory of Open Access Journals (Sweden)

    Md Kausar Alam

    Full Text Available Deletion or repression of Aspergillus nidulans ugmA (AnugmA, involved in galactofuranose biosynthesis, impairs growth and increases sensitivity to Caspofungin, a β-1,3-glucan synthesis antagonist. The A. fumigatus UgmA (AfUgmA crystal structure has been determined. From that study, AfUgmA mutants with altered enzyme activity were transformed into AnugmA▵ to assess their effect on growth and wall composition in A. nidulans. The complemented (AnugmA::wild type AfugmA strain had wild type phenotype, indicating these genes had functional homology. Consistent with in vitro studies, AfUgmA residues R182 and R327 were important for its function in vivo, with even conservative amino (RK substitutions producing AnugmA? phenotype strains. Similarly, the conserved AfUgmA loop III histidine (H63 was important for Galf generation: the H63N strain had a partially rescued phenotype compared to AnugmA▵. Collectively, A. nidulans strains that hosted mutated AfUgmA constructs with low enzyme activity showed increased hyphal surface adhesion as assessed by binding fluorescent latex beads. Consistent with previous qPCR results, immunofluorescence and ELISA indicated that AnugmA▵ and AfugmA-mutated A. nidulans strains had increased α-glucan and decreased β-glucan in their cell walls compared to wild type and AfugmA-complemented strains. Like the AnugmA▵ strain, A. nidulans strains containing mutated AfugmA showed increased sensitivity to antifungal drugs, particularly Caspofungin. Reduced β-glucan content was correlated with increased Caspofungin sensitivity. Aspergillus nidulans wall Galf, α-glucan, and β-glucan content was correlated in A. nidulans hyphal walls, suggesting dynamic coordination between cell wall synthesis and cell wall integrity.

  16. KdmB, a Jumonji Histone H3 Demethylase, Regulates Genome-Wide H3K4 Trimethylation and Is Required for Normal Induction of Secondary Metabolism in Aspergillus nidulans.

    Science.gov (United States)

    Gacek-Matthews, Agnieszka; Berger, Harald; Sasaki, Takahiko; Wittstein, Kathrin; Gruber, Clemens; Lewis, Zachary A; Strauss, Joseph

    2016-08-01

    Histone posttranslational modifications (HPTMs) are involved in chromatin-based regulation of fungal secondary metabolite biosynthesis (SMB) in which the corresponding genes-usually physically linked in co-regulated clusters-are silenced under optimal physiological conditions (nutrient-rich) but are activated when nutrients are limiting. The exact molecular mechanisms by which HPTMs influence silencing and activation, however, are still to be better understood. Here we show by a combined approach of quantitative mass spectrometry (LC-MS/MS), genome-wide chromatin immunoprecipitation (ChIP-seq) and transcriptional network analysis (RNA-seq) that the core regions of silent A. nidulans SM clusters generally carry low levels of all tested chromatin modifications and that heterochromatic marks flank most of these SM clusters. During secondary metabolism, histone marks typically associated with transcriptional activity such as H3 trimethylated at lysine-4 (H3K4me3) are established in some, but not all gene clusters even upon full activation. KdmB, a Jarid1-family histone H3 lysine demethylase predicted to comprise a BRIGHT domain, a zinc-finger and two PHD domains in addition to the catalytic Jumonji domain, targets and demethylates H3K4me3 in vivo and mediates transcriptional downregulation. Deletion of kdmB leads to increased transcription of about ~1750 genes across nutrient-rich (primary metabolism) and nutrient-limiting (secondary metabolism) conditions. Unexpectedly, an equally high number of genes exhibited reduced expression in the kdmB deletion strain and notably, this group was significantly enriched for genes with known or predicted functions in secondary metabolite biosynthesis. Taken together, this study extends our general knowledge about multi-domain KDM5 histone demethylases and provides new details on the chromatin-level regulation of fungal secondary metabolite production. PMID:27548260

  17. Functional and Physical Interaction of Blue- and Red-Light Sensors in Aspergillus nidulans

    International Nuclear Information System (INIS)

    Light sensing is very important for organisms in all biological kingdoms to adapt to changing environmental conditions. It was discovered recently that plant-like phytochrome is in- volved in light sensing in the filamentous fungus Aspergillus nidulans [1]. Here, we show that phytochrome (FphA) is part of a protein complex containing LreA (WC-1) and LreB (WC-[2, 3], two central components of the Neurospora crassa blue-light-sensing system. We found that FphA represses sexual development and mycotoxin formation, whereas LreA and LreB stimulate both. Surprisingly, FphA interacted with LreB and with VeA, another regulator involved in light sensing and mycotoxin biosynthesis. LreB also interacted with LreA. All protein interactions occurred in the nucleus, despite cytoplasmic subfractions of the proteins. Whereas the FphA-VeA interaction was dependent on the presence of the linear tetrapyrrole in FphA, the interaction between FphA and LreB was chromophore independent. These results suggest that morphological and physiological differen- tiations in A. nidulans are mediated through a network consisting of FphA, LreA, LreB, and VeA acting in a large protein complex in the nucleus, sensing red and blue light. (author)

  18. Thiamine synthesis regulates the fermentation mechanisms in the fungus Aspergillus nidulans.

    Science.gov (United States)

    Shimizu, Motoyuki; Masuo, Shunsuke; Itoh, Eriko; Zhou, Shengmin; Kato, Masashi; Takaya, Naoki

    2016-09-01

    Thiamine pyrophosphate (TPP) is a critical cofactor and its biosynthesis is under the control of TPP availability. Here we disrupted a predicted thiA gene of the fungus Aspergillus nidulans and demonstrated that it is essential for synthesizing cellular thiamine. The thiamine riboswitch is a post-transcriptional mechanism for TPP to repress gene expression and it is located on A. nidulans thiA pre-messenger RNA. The thiA riboswitch was not fully derepressed under thiamine-limited conditions, and fully derepressed under environmental stressors. Upon exposure to hypoxic stress, the fungus accumulated more ThiA and NmtA proteins, and more thiamine than under aerobic conditions. The thiA gene was required for the fungus to upregulate hypoxic branched-chain amino acids and ethanol fermentation that involve enzymes containing TPP. These findings indicate that hypoxia modulates thiA expression through the thiamine riboswitch, and alters cellular fermentation mechanisms by regulating the activity of the TPP enzymes. PMID:26967817

  19. EVALUATION OF CELL CYCLE OF Aspergillus nidulans EXPOSED TO THE EXTRACT OF Copaifera officinalis L PLANT

    Directory of Open Access Journals (Sweden)

    Simone Jurema Ruggeri Chiuchetta, Uériton Dias de Oliveira e Josy Fraccaro de Marins

    2006-12-01

    Full Text Available The oil extracted from the Copaifera officinalis L plant has been used in popular medicine to the treatment of several diseases, like cancer. In eukaryotic cells, the process of cellular proliferation follows a standard cycle, named cellular cycle. The transformation of a normal cell in a malignant one requires several steps, in which genes that control normal cellular division or cellular death are modified. Aspergillus nidulans fungus is an excellent system for the study of the cellular differentiation. Its asexual cycle results in the formation of conidia, which are disposed like chains, constituting a structure named conidiophore. This structure consists in an aerial hifae, multinucleate vesicle and uninucleate cells. Current research evaluated the capacity of the C. officinalis L plant extract in promoting alterations in the cellular cycle of A. nidulans diploid strains, by observing macroscopic and microscopic alterations in cellular growth of this fungus. Results shown that no macroscopic alterations were observed in cellular growth of strains exposed to the extract, however, microscopic alterations of conidiophore have been observed in the different extract concentrations analyzed. In this way, the study of the action of C. officinalis L plant extract becomes important considering the fact that this substance is capable to promote alterations in cellular cycle of eukaryotic cells.

  20. Roles of Aspergillus nidulans Cdc42/Rho GTPase regulators in hyphal morphogenesis and development.

    Science.gov (United States)

    Si, Haoyu; Rittenour, William R; Harris, Steven D

    2016-01-01

    The Rho-related family of GTPases are pivotal regulators of morphogenetic processes in diverse eukaryotic organisms. In the filamentous fungi two related members of this family, Cdc42 and Rac1, perform particularly important roles in the establishment and maintenance of hyphal polarity. The activity of these GTPases is tightly controlled by two sets of regulators: guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs). Despite the importance of Cdc42 and Rac1 in polarized hyphal growth, the morphogenetic functions of their cognate GEFs and GAPs have not been widely characterized in filamentous fungi outside the Saccharomycotina. Here we present a functional analysis of the Aspergillus nidulans homologs of the yeast GEF Cdc24 and the yeast GAP Rga1. We show that Cdc24 is required for the establishment of hyphal polarity and localizes to hyphal tips. We also show that Rga1 is necessary for the suppression of branching in developing conidiophores. During asexual development Rga1 appears to act primarily via Cdc42 and in doing so serves as a critical determinant of conidiophore architecture. Our results provide new insight into the roles of Cdc42 during development in A nidulans. PMID:26932184

  1. New Aspercryptins, Lipopeptide Natural Products, Revealed by HDAC Inhibition in Aspergillus nidulans.

    Science.gov (United States)

    Henke, Matthew T; Soukup, Alexandra A; Goering, Anthony W; McClure, Ryan A; Thomson, Regan J; Keller, Nancy P; Kelleher, Neil L

    2016-08-19

    Unlocking the biochemical stores of fungi is key for developing future pharmaceuticals. Through reduced expression of a critical histone deacetylase in Aspergillus nidulans, increases of up to 100-fold were observed in the levels of 15 new aspercryptins, recently described lipopeptides with two noncanonical amino acids derived from octanoic and dodecanoic acids. In addition to two NMR-verified structures, MS/MS networking helped uncover an additional 13 aspercryptins. The aspercryptins break the conventional structural orientation of lipopeptides and appear "backward" when compared to known compounds of this class. We have also confirmed the 14-gene aspercryptin biosynthetic gene cluster, which encodes two fatty acid synthases and several enzymes to convert saturated octanoic and dodecanoic acid to α-amino acids. PMID:27310134

  2. Mitotic and meiotic instability produced by an informational suppressor in Aspergillus nidulans Instabilidade mitótica e meiótica produzida por um supressor informacional em Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Melissa Gracite de Melo Franzoni

    2000-05-01

    Full Text Available The genetic instability induced by the informational suppressor suO1 in Aspergillus nidulans is described. suO1 was selected through the properties of coreversion of several physiologically unrelated mutations. This mutation decreased the conidia and ascospores viability of the suppressor strains. These strains were unstable at mitosis and meiosis, producing improved derivatives, phenotypically different from the original strains. Meiotic crosses, heterozygous for the suppressor mutation, produced barren cleistothecia. suO1 was unstable in the restoration of the genetic alterations present in the genome of M-15 mutant, producing more than 25.0% unsuppressed progeny in heterozygous crosses for auxotrophyc mutations (for instance, su, ribo x su+, ribo+ . Our results suggested that suO1 altered the fidelity of the translation process, inducing mistranslation of normal and mutant mRNAsA instabilidade genética de linhagens de Aspergillus nidulans, portadoras de um supressor informacional (suO1, foi estudada no presente trabalho. suO1 foi selecionado através de sua capacidade de suprimir várias mutações auxotróficas e de coloração de conídios, presentes no genoma do mutante M-15. Este supressor mostrou-se também capaz de reduzir a fertilidade e a viabilidade conidial das linhagens suprimidas. Estas linhagens mostraram-se instáveis na mitose, produzindo espontaneamente setores mitóticos fenotipicamente distintos da linhagem original, e na meiose, produzindo cleistotécios contendo reduzido número de ascósporos viáveis. Em cruzamentos heterozigotos (su, ribo x su+, ribo+ mais de 25.0% da progênie exibiu o fenótipo mutante ribo, destacando a baixa eficiência da mutação suO1. Nossos resultados sugerem que suO1 induz erros na tradução de mRNAs selvagens e mutantes

  3. The Aspergillus nidulans cetA and calA genes are involved in conidial germination and cell wall morphogenesis.

    Science.gov (United States)

    Belaish, Ravit; Sharon, Haim; Levdansky, Emma; Greenstein, Shulamit; Shadkchan, Yana; Osherov, Nir

    2008-03-01

    The Aspergillus nidulans genes cetA (AN3079.2) and calA (AN7619.2) encode a novel class of fungal thaumatin-like proteins of unknown function. Deletion of cetA does not result in an observable phenotype [Greenstein, S., Shadkchan, Y., Jadoun, J., Sharon, C., Markovich, S., Osherov, N., 2006. Analysis of the Aspergillus nidulans thaumatin-like cetA gene and evidence for transcriptional repression of pyr4 expression in the cetA-disrupted strain. Fungal Genet. Biol. 43, 42-53]. We prepared knockout calA and calA/cetA A. nidulans strains. The calA mutants were phenotypically identical to the wild-type. In contrast, the cetA/calA double mutant showed a synthetic lethal phenotype suggesting that the two genes affect a single function or pathway: most of its conidia were completely inhibited in germination. Many collapsed and underwent lysis. A few showed abnormal germination characterized by short swollen hyphae and abnormal hyphal branching. Nongerminated conidia contained a single condensed nucleus suggesting a block in early germination. This is the first functional analysis of the novel cetA/calA family of thaumatin-like genes and their role in A. nidulans conidial germination. We show that CETA and CALA are secreted proteins that together play an essential role in early conidial germination. PMID:17703972

  4. Aspergillus nidulans Natural Product Biosynthesis Is Regulated by MpkB, a Putative Pheromone Response Mitogen-Activated Protein Kinase

    International Nuclear Information System (INIS)

    The Aspergillus nidulans putative mitogen-activated protein kinase encoded by mpkB has a role in natural product biosynthesis. An mpkB mutant exhibited a decrease in sterigmatocystin gene expression and low mycotoxin levels. The mutation also affected the expression of genes involved in penicillin and terrequinone A synthesis. mpkB was necessary for normal expression of laeA, which has been found to regulate secondary metabolism gene clusters. (author)

  5. CHPA, a Cysteine- and Histidine-Rich-Domain-Containing Protein, Contributes to Maintenance of the Diploid State in Aspergillus nidulans

    OpenAIRE

    Sadanandom, Ari; Findlay, Kim; Doonan, John H.; Schulze-Lefert, Paul; Shirasu, Ken

    2004-01-01

    The alternation of eukaryotic life cycles between haploid and diploid phases is crucial for maintaining genetic diversity. In some organisms, the growth and development of haploid and diploid phases are nearly identical, and one might suppose that all genes required for one phase are likely to be critical for the other phase. Here, we show that targeted disruption of the chpA (cysteine- and histidine-rich-domain- [CHORD]-containing protein A) gene in haploid Aspergillus nidulans strains gives...

  6. Doxorubicin and etoposide induce somatic recombination in diploid cells of Aspergillus nidulans Doxorubicina e etoposida induzem a recombinação somática em células diplóides de Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Simone Jurema Ruggeri Chiuchetta

    2002-09-01

    Full Text Available Doxorubicin and etoposide are intercalating agents that inhibit the action of the enzyme topoisomerase II. Both drugs present therapeutic activity in numerous human neoplasms In the present work the recombinagenic potential of these drugs was evaluated by ascomycete Aspergillus nidulans. Their effects on the asexual cycle of A. nidulans was also appraised. Two heterozygous diploid strains of A. nidulans, a wild (uvsH+//uvsH+ and a defective to the DNA repair (uvsH//uvsH were used. The drugs' recombinagenic potential was evaluated by their capacity to induce homozygosis of recessive genes from heterozygous cells. Both drugs have a recombinagenic effect on diploid cells of A. nidulans. Doxorubicin and etoposide are potentially capable to induce secondary malignancies, mediated by the mitotic crossing-over in eukaryotic cells.Doxorubicina e etoposida são agentes intercalantes que inibem a ação da enzima topoisomerase II. Ambas drogas são amplamente utilizadas no tratamento de neoplasias. O potencial recombinagênico destes agentes e seus efeitos sobre o ciclo assexual de Aspergillus nidulans foram avaliados no presente trabalho. Duas linhagens diplóides heterozigotas foram utilizadas: uma selvagem (uvsH+//uvsH+ e outra deficiente para o reparo do DNA (uvsH//uvsH. O potencial recombinagênico destas drogas foi avaliado pela indução de homozigose de genes recessivos a partir de células heterozigotas. Doxorubicina e etoposida apresentaram efeitos recombinagênicos em ambas linhagens utilizadas. Os resultados permitem concluir que doxorubicina e etoposida são agentes potencialmente capazes de induzir malignidades secundárias, mediadas pelo crossing-over mitótico, em células diplóides eucariotas.

  7. Arabinase induction and carbon catabolite repression in Aspergillus niger and Aspergillus nidulans.

    NARCIS (Netherlands)

    Veen, van der P.

    1995-01-01

    The first aim of this thesis was to get a better understanding of the properties and the induction features of arabinan degrading enzymes and enzymes involved in the intracellular L-arabinose catabolic pathway in Aspergillus niger. The second aim was to understand the which role carbon catabolite re

  8. Expression of Aspergillus nidulans phy Gene in Nicotiana benthamiana Produces Active Phytase with Broad Specificities

    Directory of Open Access Journals (Sweden)

    Tae-Kyun Oh

    2014-09-01

    Full Text Available A full-length phytase gene (phy of Aspergillus nidulans was amplified from the cDNA library by polymerase chain reaction (PCR, and it was introduced into a bacterial expression vector, pET-28a. The recombinant protein (rPhy-E, 56 kDa was overexpressed in the insoluble fraction of Escherichia coli culture, purified by Ni-NTA resin under denaturing conditions and injected into rats as an immunogen. To express A. nidulans phytase in a plant, the full-length of phy was cloned into a plant expression binary vector, pPZP212. The resultant construct was tested for its transient expression by Agrobacterium-infiltration into Nicotiana benthamiana leaves. Compared with a control, the agro-infiltrated leaf tissues showed the presence of phy mRNA and its high expression level in N. benthamiana. The recombinant phytase (rPhy-P, 62 kDa was strongly reacted with the polyclonal antibody against the nonglycosylated rPhy-E. The rPhy-P showed glycosylation, two pH optima (pH 4.5 and pH 5.5, an optimum temperature at 45~55 °C, thermostability and broad substrate specificities. After deglycosylation by peptide-N-glycosidase F (PNGase-F, the rPhy-P significantly lost the phytase activity and retained 1/9 of the original activity after 10 min of incubation at 45 °C. Therefore, the deglycosylation caused a significant reduction in enzyme thermostability. In animal experiments, oral administration of the rPhy-P at 1500 U/kg body weight/day for seven days caused a significant reduction of phosphorus excretion by 16% in rat feces. Besides, the rPhy-P did not result in any toxicological changes and clinical signs.

  9. Functional characterization of Aspergillus nidulans ypkA, a homologue of the mammalian kinase SGK.

    Science.gov (United States)

    Colabardini, Ana Cristina; Brown, Neil Andrew; Savoldi, Marcela; Goldman, Maria Helena S; Goldman, Gustavo Henrique

    2013-01-01

    The serum- and glucocorticoid-regulated protein kinase (SGK) is an AGC kinase involved in signal cascades regulated by glucocorticoid hormones and serum in mammals. The Saccharomyces cerevisiae ypk1 and ypk2 genes were identified as SGK homologues and Ypk1 was shown to regulate the balance of sphingolipids between the inner and outer plasma membrane. This investigation characterized the Aspergillus nidulans YPK1 homologue, YpkA, representing the first filamentous fungal YPK1 homologue. Two conditional mutant strains were constructed by replacing the endogenous ypk1 promoter with two different regulatable promoters, alcA (from the alcohol dehydrogenase gene) and niiA (from the nitrate reductase gene). Both constructs confirmed that ypkA was an essential gene in A. nidulans. Repression of ypkA caused decreased radial growth, a delay in conidial germination, deficient polar axis establishment, intense branching during late stages of growth, a lack of asexual spores, and a terminal phenotype. Membrane lipid polarization, endocytosis, eisosomes and vacuolar distribution were also affected by ypkA repression, suggesting that YpkA plays a role in hyphal morphogenesis via coordinating the delivery of cell membrane and wall constituents to the hyphal apex. The A. nidulans Pkh1 homologue pkhA was also shown to be an essential gene, and preliminary genetic analysis suggested that the ypkA gene is not directly downstream of pkhA or epistatic to pkhA, rather, ypkA and pkhA are genetically independent or in parallel. BarA is a homologue of the yeast Lag1 acyl-CoA-dependent ceramide synthase, which catalyzes the condensation of phytosphingosine with a fatty acyl-CoA to form phytoceramide. When barA was absent, ypkA repression was lethal to the cell. Therefore, there appears to be a genetic interaction between ypkA, barA, and the sphingolipid synthesis. Transcriptional profiling of ypkA overexpression and down-regulation revealed several putative YpkA targets associated with the

  10. Functional characterization of Aspergillus nidulans ypkA, a homologue of the mammalian kinase SGK.

    Directory of Open Access Journals (Sweden)

    Ana Cristina Colabardini

    Full Text Available The serum- and glucocorticoid-regulated protein kinase (SGK is an AGC kinase involved in signal cascades regulated by glucocorticoid hormones and serum in mammals. The Saccharomyces cerevisiae ypk1 and ypk2 genes were identified as SGK homologues and Ypk1 was shown to regulate the balance of sphingolipids between the inner and outer plasma membrane. This investigation characterized the Aspergillus nidulans YPK1 homologue, YpkA, representing the first filamentous fungal YPK1 homologue. Two conditional mutant strains were constructed by replacing the endogenous ypk1 promoter with two different regulatable promoters, alcA (from the alcohol dehydrogenase gene and niiA (from the nitrate reductase gene. Both constructs confirmed that ypkA was an essential gene in A. nidulans. Repression of ypkA caused decreased radial growth, a delay in conidial germination, deficient polar axis establishment, intense branching during late stages of growth, a lack of asexual spores, and a terminal phenotype. Membrane lipid polarization, endocytosis, eisosomes and vacuolar distribution were also affected by ypkA repression, suggesting that YpkA plays a role in hyphal morphogenesis via coordinating the delivery of cell membrane and wall constituents to the hyphal apex. The A. nidulans Pkh1 homologue pkhA was also shown to be an essential gene, and preliminary genetic analysis suggested that the ypkA gene is not directly downstream of pkhA or epistatic to pkhA, rather, ypkA and pkhA are genetically independent or in parallel. BarA is a homologue of the yeast Lag1 acyl-CoA-dependent ceramide synthase, which catalyzes the condensation of phytosphingosine with a fatty acyl-CoA to form phytoceramide. When barA was absent, ypkA repression was lethal to the cell. Therefore, there appears to be a genetic interaction between ypkA, barA, and the sphingolipid synthesis. Transcriptional profiling of ypkA overexpression and down-regulation revealed several putative YpkA targets

  11. Cremophor EL stimulates mitotic recombination in uvsH//uvsH diploid strain of Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Cleverson Busso

    2004-03-01

    Full Text Available Cremophor EL is a solubilizer and emulsifier agent used in the pharmaceutical and foodstuff industries. The solvent is the principal constituent of paclitaxel's clinical formulation vehicle. Since mitotic recombination plays a crucial role in multistep carcinogenesis, the study of the recombinagenic potential of chemical compounds is of the utmost importance. In our research genotoxicity of cremophor EL has been studied by using an uvsH//uvsH diploid strain of Aspergillus nidulans. Since it spends a great part of its cell cycle in the G2period, this fungus is a special screening system for the study of mitotic recombination induced by chemical substances. Homozygotization Indexes (HI for paba and bi markers from heterozygous B211//A837 diploid strain were determined for the evaluation of the recombinagenic effect of cremophor EL. It has been shown that cremophor EL induces increase in mitotic crossing-over events at nontoxic concentrations (0.05 and 0.075% v/v.Cremofor EL (CEL é um solubilizante e emulsificante amplamente utilizado nas indústrias farmacêuticas e de gêneros alimentícios. É o principal veículo empregado nas formulações clínicas do antineoplásico paclitaxel. Considerando-se que a recombinação mitótica desempenha importante função no processo de carcinogênese, o estudo de substâncias químicas com potencial recombinagênico assume importância crucial, no sentido de se detectar aquelas que eventualmente possam atuar como promotoras de neoplasias. A genotoxicidade do cremofor EL foi estudada no presente trabalho, utilizando-se uma linhagem diplóide uvsH//uvsH de Aspergillus nidulans. Neste fungo as células vegetativas comumente repousam no período G2 do ciclo celular, facilitando a ocorrência da recombinação mitótica. O efeito recombinagênico do CEL foi avaliado através da determinação dos Índices de Homozigotização para os marcadores nutricionais paba e bi do diplóide heterozigoto B211//A837. Os

  12. Antimutagenic action of Lentinula edodes and Agaricus blazei on Aspergillus nidulans conidia Ação antimutagênica de Lentinula edodes e Agaricus blazei em conídios de Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Edneia A. Souza-Paccola

    2004-12-01

    Full Text Available The antimutagenic effect of the mushrooms Lentinula edodes and Agaricus blazei was studied on conidia of Aspergillus nidulans when exposed to short wave ultraviolet light. Two strains of A. nidulans were used. For the preparation of the extracts, the fresh mushrooms were left in aqueous infusion for 12 hours and heated in a water bath for 15 min at 100ºC, and then the material was filtered. The dehydrated mushrooms were left in aqueous infusion for 12 hours and to filtrated. Both filtrates were used as extracts. A. nidulans conidia were incubated for three hours in water and in mushroom extracts and only after were exposed to UV light (pre-treatment. A. nidulans conidia were suspended in water and in mushroom extracts and immediately submitted to UV light (post-treatment. Conidial suspension in water and in mushroom extracts but without exposure to the mutagenic agent were used as controls. After mutagenic treatment, it was observed an increase in the survival rate of the A. nidulans and a decrease in the percentage of morphologic mutants on conidia treated with mushroom extracts. Our results demonstrated the radioprotective and antimutagenic effect of L. edodes and A. blazei mushrooms on eukaryotic cells when exposed to UV radiation.O efeito antimutagênico dos cogumelos Lentinula edodes e Agaricus blazei foram estudados sobre conídios de Aspergillus nidulans quando expostos à luz ultravioleta de comprimento de onda curto. Duas linhagens de A. nidulans foram usadas. Para o preparo dos extratos, os cogumelos frescos permaneceram em infusão aquosa por 12 horas e em seguida foram aquecidos em banho-maria por 15 min à 100ºC e a seguir o material foi filtrado. Os cogumelos desidratados foram deixados em infusão aquosa por 12 horas e a seguir filtrados. Ambos os filtrados foram usados como extratos. Os conídios de A. nidulans foram incubados por três horas em água e em extrato de cogumelo e somente após foram expostos a luz ultravioleta

  13. Mutations affecting extracellular protease production in the filamentous fungus Aspergillus nidulans.

    Science.gov (United States)

    Katz, M E; Flynn, P K; vanKuyk, P A; Cheetham, B F

    1996-04-10

    The extracellular proteases of Aspergillus nidulans are known to be regulated by carbon, nitrogen and sulphur metabolite repression. In this study, a mutant with reduced levels of extracellular protease was isolated by screening for loss of halo production on milk plates. Genetic analysis of the mutant showed that it contains a single, recessive mutation, in a gene which we have designated xprE, located on chromosome VI. The xprE1 mutation affected the production of extracellular proteases in response to carbon, nitrogen and, to a lesser extent, sulphur limitation. Three reversion mutations, xprF1, xprF2 and xprG1, which suppress xprE1, were characterised. Both xprF and xprG map to chromosome VII but the two genes are unlinked. The xprF1, xprF2 and xprG1 mutants showed high levels of milk-clearing activity on medium containing milk as a carbon source but reduced growth on a number of nitrogen sources. Evidence is presented that the xprE1 and xprG1 mutations alter expression of more than one protease and affect levels of alkaline protease gene mRNA.

  14. Dynamics of actin cables in polarized growth of the filamentous fungus Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Anna eBergs

    2016-05-01

    Full Text Available Highly polarized growth of filamentous fungi requires a continuous supply of proteins and lipids to the hyphal tip. This transport is managed by vesicle trafficking via the actin and microtubule cytoskeletons and their associated motor proteins. Particularly, actin cables originating from the hyphal tip are essential for hyphal growth. Although specific marker proteins to visualize actin cables have been developed in filamentous fungi, the exact organization and dynamics of actin cables has remained elusive. Here we visualized actin cables using tropomyosin (TpmA and Lifeact fused to fluorescent proteins in Aspergillus nidulans and studied the dynamics and regulation. GFP tagged TpmA visualized dynamic actin cables formed from the hyphal tip with cycles of elongation and shrinkage. The elongation and shrinkage rates of actin cables were similar and approximately 0.6 μm/s. Comparison of actin markers revealed that high concentrations of Lifeact reduced actin dynamics. Simultaneous visualization of actin cables and microtubules suggests temporally and spatially coordinated polymerization and depolymerization between the two cytoskeletons. Our results provide new insights into the molecular mechanism of ordered polarized growth regulated by actin cables and microtubules.

  15. A genomics based discovery of secondary metabolite biosynthetic gene clusters in Aspergillus ustus.

    Directory of Open Access Journals (Sweden)

    Borui Pi

    Full Text Available Secondary metabolites (SMs produced by Aspergillus have been extensively studied for their crucial roles in human health, medicine and industrial production. However, the resulting information is almost exclusively derived from a few model organisms, including A. nidulans and A. fumigatus, but little is known about rare pathogens. In this study, we performed a genomics based discovery of SM biosynthetic gene clusters in Aspergillus ustus, a rare human pathogen. A total of 52 gene clusters were identified in the draft genome of A. ustus 3.3904, such as the sterigmatocystin biosynthesis pathway that was commonly found in Aspergillus species. In addition, several SM biosynthetic gene clusters were firstly identified in Aspergillus that were possibly acquired by horizontal gene transfer, including the vrt cluster that is responsible for viridicatumtoxin production. Comparative genomics revealed that A. ustus shared the largest number of SM biosynthetic gene clusters with A. nidulans, but much fewer with other Aspergilli like A. niger and A. oryzae. These findings would help to understand the diversity and evolution of SM biosynthesis pathways in genus Aspergillus, and we hope they will also promote the development of fungal identification methodology in clinic.

  16. Identificação do potencial amilolítico de linhagens mutantes do fungo filamentoso Aspergillus nidulans Identification of the amylolytic potential of mutant strains of the filamentous fungi Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Izabel Aparecida Soares

    2010-09-01

    Full Text Available As amilases estão entre as mais importantes enzimas industriais, apresentando grande importância biotecnológica, principalmente na indústria alimentícia. Com o avanço no conhecimento das enzimas, a utilização dos fungos como fonte de enzimas vem adquirindo um status de destaque nas mais variadas áreas industriais e comerciais. Diante disso, o presente estudo procurou identificar a presença de atividade amilolítica em quatro linhagens do fungo filamentoso Aspergillus nidulans, selvagem, PAT, biA1methG1 e CLB3, utilizando dois meios distintos de cultura, BDA e Meio Completo a 2% amido, variando os tratamentos com adição ou não de glicose. Foram determinados o diâmetro médio da colônia, o diâmetro médio do halo e o Índice Enzimático. Como resultados, todas as linhagens testadas foram capazes de degradar o amido quando na ausência de glicose, porém o tratamento que obteve estatisticamente melhor crescimento e maior degradação do amido foi o MC sem glicose a 2% amido e a linhagem que se demonstrou potencialmente degradadora de amido foi o mutante CLB3. Conclui-se, portanto, que Aspergillus nidulans pode ser considerado como um produtor de amilases.The amylases are among the most important industrial enzymes showing great biotechnological importance, mainly in the food industry. Due to the advance knowledge in enzyme research, the use of fungi as source of enzymes has acquired a prominent status in most varied industrial and commercial areas. Thus, the present study tried to identify the presence of the amylolytic activity in four stains of filamentous fungi Aspergillus nidulans, selvagem, PAT, biA1methG1 and CLB3 by using two different culture means, PDA and Complete mean with 2% starch, varying the treatments with and without the addition of glucose. The colony average diameter, the halo average diameter, and the enzymatic index were determined. The results show that all strains tested were capable of degrading starch in the

  17. Gmca is a putative glucose-methanol-choline oxidoreductase required for the induction of asexual development in aspergillus nidulans

    OpenAIRE

    Oier Etxebeste; Erika Herrero-García; Cortese, Marc S.; Aitor Garzia; Elixabet Oiartzabal-Arano; Vivian de los Ríos; Unai Ugalde; Espeso, Eduardo A.

    2012-01-01

    Aspergillus nidulans asexual differentiation is induced by Upstream Developmental Activators (UDAs) that include the bZIP-type Transcription Factor (TF) FlbB. A 2D-PAGE/MS-MS-coupled screen for proteins differentially expressed in the presence and absence of FlbB identified 18 candidates. Most candidates belong to GO term classes involved in osmotic and/or oxidative stress response. Among these, we focused on GmcA, a putative glucose-methanol-choline oxidoreductase which is upregulated in a Δ...

  18. The formamidase gene of Aspergillus nidulans: regulation by nitrogen metabolite repression and transcriptional interference by an overlapping upstream gene.

    OpenAIRE

    Fraser, J A; Davis, M A; Hynes, M J

    2001-01-01

    The ability to utilize formamide as a sole nitrogen source has been found in numerous fungi. We have cloned the fmdS gene encoding a formamidase from Aspergillus nidulans and found that it belongs to a highly conserved family of proteins separate from the major amidase families. The expression of fmdS is primarily regulated via AreA-mediated nitrogen metabolite repression and does not require the addition of exogenous inducer. Consistent with this, deletion analysis of the 5' region of fmdS h...

  19. Localization and function of calmodulin in live-cells of Aspergillus nidulans.

    Science.gov (United States)

    Chen, Shaochun; Song, Yiju; Cao, Jinling; Wang, Gang; Wei, Hua; Xu, Xushi; Lu, Ling

    2010-03-01

    Calmodulin (CaM) is a small, eukaryotic protein that reversibly binds Ca(2+). Study of CaM localization in genetically tractable organisms has yielded many insights into CaM function. Here, we described the dynamic localization of Aspergillus nidulans CaM (AnCaM) in live-cells by using recombination strains with homologous, single cross-over insertions at the target gene which placed the GFP fused copy under the inducible alcA promoter and the RFP-CaM integration under the native cam promoter. We found that the localization of CaM fusion was quite dynamic throughout the hypha and was concentrated to the active growing sites during germination, hyphal growth, cytokinesis and conidiation. The depletion of CaM by alcA promoter repression induced the explicit abnormalities of germlings with the swollen germ tubes. In addition, the position of highly concentrated GFP-CaM in the extreme apex seemed to determine the hyphal orientation. These data collectively suggest that CaM is constantly required for new hyphal growth. In contrast to this constant accumulation at the apex, GFP-CaM was only transiently localized at septum sites during cytokinesis. Notably, depletion of CaM caused the defect of septation with a completely blocked septum formation indicating that the transient CaM accumulation at the septum site is essential for septation. Moreover, the normal localization of CaM at a hyphal tip required the presence of the functional actin cytoskeleton and the motor protein KipA, which is indispensable for positioning Spitzenkörper. This is the first report of CaM localization and function in live-cells by the site-specific homologous integration in filamentous fungi.

  20. Recombinant production and characterisation of two related GH5 endo-β-1,4-mannanases from Aspergillus nidulans FGSC A4 showing distinctly different transglycosylation capacity

    DEFF Research Database (Denmark)

    Dilokpimol, Adiphol; Nakai, Hiroyuki; Gotfredsen, Charlotte Held;

    2011-01-01

    The glycoside hydrolase family 5 (GH5) endo-β-1,4-mannanases ManA and ManC from Aspergillus nidulans FGSC A4 were produced in Pichia pastoris X33 and purified in high yields of 120 and 145mg/L, respectively, from the culture supernatants. Both enzymes showed increasing catalytic efficiency (kcat...

  1. A WDR Gene Is a Conserved Member of a Chitin Synthase Gene Cluster and Influences the Cell Wall in Aspergillus nidulans

    Science.gov (United States)

    Guerriero, Gea; Silvestrini, Lucia; Obersriebnig, Michael; Hausman, Jean-Francois; Strauss, Joseph; Ezcurra, Inés

    2016-01-01

    WD40 repeat (WDR) proteins are pleiotropic molecular hubs. We identify a WDR gene that is a conserved genomic neighbor of a chitin synthase gene in Ascomycetes. The WDR gene is unique to fungi and plants, and was called Fungal Plant WD (FPWD). FPWD is within a cell wall metabolism gene cluster in the Ascomycetes (Pezizomycotina) comprising chsD, a Chs activator and a GH17 glucanase. The FPWD, AN1556.2 locus was deleted in Aspergillus nidulans strain SAA.111 by gene replacement and only heterokaryon transformants were obtained. The re-annotation of Aspergilli genomes shows that AN1556.2 consists of two tightly linked separate genes, i.e., the WDR gene and a putative beta-flanking gene of unknown function. The WDR and the beta-flanking genes are conserved genomic neighbors localized within a recently identified metabolic cell wall gene cluster in genomes of Aspergilli. The heterokaryons displayed increased susceptibility to drugs affecting the cell wall, and their phenotypes, observed by optical, confocal, scanning electron and atomic force microscopy, suggest cell wall alterations. Quantitative real-time PCR shows altered expression of some cell wall-related genes. The possible implications on cell wall biosynthesis are discussed. PMID:27367684

  2. LAMMER Kinase LkhA plays multiple roles in the vegetative growth and asexual and sexual development of Aspergillus nidulans.

    Directory of Open Access Journals (Sweden)

    Eun-Hye Kang

    Full Text Available LAMMER kinase plays pivotal roles in various physiological processes in eukaryotes; however, its function in filamentous fungi is not known. We performed molecular studies on the function of the Aspergillus nidulans LAMMER kinase, LkhA, and report its involvement in multiple developmental processes. The gene for LkhA was highly expressed during reproductive organ development, such as that of conidiophores and cleistothecia. During vegetative growth, the patterns of germ tube emergence and hyphal polarity were changed and septation was increased by lkhA deletion. Northern analyses showed that lkhA regulated the transcription of brlA, csnD, and ppoA, which supported the detrimental effect of lkhA-deletion on asexual and sexual differentiation. LkhA also affected expression of cyclin-dependent kinase NimX(cdc2, a multiple cell cycle regulator, and StuA, an APSES family of fungal transcription factors that play pivotal roles in multiple differentiation processes. Here, for the first time, we present molecular evidence showing that LAMMER kinase is involved in A. nidulans development by modulating the expression of key regulators of developmental processes.

  3. Stress tolerances of nullmutants of function-unknown genes encoding menadione stress-responsive proteins in Aspergillus nidulans.

    Science.gov (United States)

    Leiter, Éva; Bálint, Mihály; Miskei, Márton; Orosz, Erzsébet; Szabó, Zsuzsa; Pócsi, István

    2016-07-01

    A group of menadione stress-responsive function-unkown genes of Aspergillus nidulans (Locus IDs ANID_03987.1, ANID_06058.1, ANID_10219.1, and ANID_10260.1) was deleted and phenotypically characterized. Importantly, comparative and phylogenetic analyses of the tested A. nidulans genes and their orthologs shed light only on the presence of a TANGO2 domain with NRDE protein motif in the translated ANID_06058.1 gene but did not reveal any recognizable protein-encoding domains in other protein sequences. The gene deletion strains were subjected to oxidative, osmotic, and metal ion stress and, surprisingly, only the ΔANID_10219.1 mutant showed an increased sensitivity to 0.12 mmol l(-1) menadione sodium bisulfite. The gene deletions affected the stress sensitivities (tolerances) irregularly, for example, some strains grew more slowly when exposed to various oxidants and/or osmotic stress generating agents, meanwhile the ΔANID_10260.1 mutant possessed a wild-type tolerance to all stressors tested. Our results are in line with earlier studies demonstrating that the deletions of stress-responsive genes do not confer necessarily any stress-sensitivity phenotypes, which can be attributed to compensatory mechanisms based on other elements of the stress response system with overlapping functions.

  4. The old 3-oxoadipate pathway revisited: new insights in the catabolism of aromatics in the saprophytic fungus Aspergillus nidulans.

    Science.gov (United States)

    Martins, Tiago M; Hartmann, Diego O; Planchon, Sébastien; Martins, Isabel; Renaut, Jenny; Silva Pereira, Cristina

    2015-01-01

    Aspergilli play major roles in the natural turnover of elements, especially through the decomposition of plant litter, but the end catabolism of lignin aromatic hydrocarbons remains largely unresolved. The 3-oxoadipate pathway of their degradation combines the catechol and the protocatechuate branches, each using a set of specific genes. However, annotation for most of these genes is lacking or attributed to poorly- or un-characterised families. Aspergillus nidulans can utilise as sole carbon/energy source either benzoate or salicylate (upstream aromatic metabolites of the protocatechuate and the catechol branches, respectively). Using this cultivation strategy and combined analyses of comparative proteomics, gene mining, gene expression and characterisation of particular gene-replacement mutants, we precisely assigned most of the steps of the 3-oxoadipate pathway to specific genes in this fungus. Our findings disclose the genetically encoded potential of saprophytic Ascomycota fungi to utilise this pathway and provide means to untie associated regulatory networks, which are vital to heightening their ecological significance.

  5. The pH dependence of the mutagenicity of methyl benzimidazol-2-yl carbamate (MBC) towards Aspergillus nidulans (Eidam) Winter and Cladosporium cucumerinum Ellis & Arth.

    Science.gov (United States)

    Nirenberg, H I; Speakman, J B

    1981-01-01

    The ability of methyl benzimidazol-2-yl carbamate (MBC) to induce point mutations to carboxin and MBC resistance in Aspergillus nidulans (Eidam) Winter and Cladosporium cucumerinum Ellis & Arth. was dependent upon the pH value of the agar medium into which it had been incorporated. The relevance of this in relation to testing chemicals for a possible mutagenic activity with microorganisms is discussed. PMID:7010148

  6. An efficient arabinoxylan-debranching α-l-arabinofuranosidase of family GH62 from Aspergillus nidulans contains a secondary carbohydrate binding site

    DEFF Research Database (Denmark)

    Wilkens, Casper; Andersen, Susan; Petersen, Bent O.;

    2016-01-01

    An α-l-arabinofuranosidase of GH62 from Aspergillus nidulans FGSC A4 (AnAbf62A-m2,3) has an unusually high activity towards wheat arabinoxylan (WAX) (67 U/mg; kcat = 178/s, Km = 4.90 mg/ml) and arabinoxylooligosaccharides (AXOS) with degrees of polymerisation (DP) 3–5 (37–80 U/mg), but about 50 t...

  7. Comparative Reannotation of 21 Aspergillus Genomes

    Energy Technology Data Exchange (ETDEWEB)

    Salamov, Asaf; Riley, Robert; Kuo, Alan; Grigoriev, Igor

    2013-03-08

    We used comparative gene modeling to reannotate 21 Aspergillus genomes. Initial automatic annotation of individual genomes may contain some errors of different nature, e.g. missing genes, incorrect exon-intron structures, 'chimeras', which fuse 2 or more real genes or alternatively splitting some real genes into 2 or more models. The main premise behind the comparative modeling approach is that for closely related genomes most orthologous families have the same conserved gene structure. The algorithm maps all gene models predicted in each individual Aspergillus genome to the other genomes and, for each locus, selects from potentially many competing models, the one which most closely resembles the orthologous genes from other genomes. This procedure is iterated until no further change in gene models is observed. For Aspergillus genomes we predicted in total 4503 new gene models ( ~;;2percent per genome), supported by comparative analysis, additionally correcting ~;;18percent of old gene models. This resulted in a total of 4065 more genes with annotated PFAM domains (~;;3percent increase per genome). Analysis of a few genomes with EST/transcriptomics data shows that the new annotation sets also have a higher number of EST-supported splice sites at exon-intron boundaries.

  8. Identificación de la quinasa HalA y el estudio de su papel en la regulación de la homeostasis de cationes en Aspergillus nidulans

    OpenAIRE

    Cobeño Fariñas, Laura

    2010-01-01

    Aspergillus nidulans es un hongo filamentoso que presenta un tipo de crecimiento hiperpolarizado formando largos filamentos denominados hifas y muestra ramificación lateral en los compartimentos celulares más posteriores de la hifa. El genoma de A. nidulans se publicó en diciembre de 2005. La disponibilidad de dicha información es una nueva e importante herramienta de trabajo y supone un avance significativo que permitirá seguir utilizando A. nidulans como organismo modelo, genéticamente mani...

  9. Expression and secretion in Aspergillus nidulans and Aspergillus niger of a cell surface glycoprotein from the cattle tick, Boophilus microplus, by using the fungal amdS promoter system.

    OpenAIRE

    Turnbull, I F; Smith, D R; Sharp, P. J.; Cobon, G S; Hynes, M J

    1990-01-01

    A cell surface glycoprotein (Bm86) from cells of the digestive tract of the cattle tick Boophilus microplus, which has been shown to elicit a protective immunological response in vaccinated cattle, was expressed and secreted in the filamentous fungi Aspergillus nidulans and Aspergillus niger by using the fungal amdS promoter system. The cloned gene coded for the Bm86 secretory signal and all of the Bm86 mature polypeptide except for the hydrophobic carboxy-terminal segment. High levels of Bm8...

  10. Co-cultivation of Aspergillus nidulans Recombinant Strains Produces an Enzymatic Cocktail as Alternative to Alkaline Sugarcane Bagasse Pretreatment

    Science.gov (United States)

    Lima, Matheus S.; Damasio, André R. de L.; Crnkovic, Paula M.; Pinto, Marcelo R.; da Silva, Ana M.; da Silva, Jean C. R.; Segato, Fernando; de Lucas, Rosymar C.; Jorge, João A.; Polizeli, Maria de L. T. de M.

    2016-01-01

    Plant materials represent a strategic energy source because they can give rise to sustainable biofuels through the fermentation of their carbohydrates. A clear example of a plant-derived biofuel resource is the sugar cane bagasse exhibiting 60–80% of fermentable sugars in its composition. However, the current methods of plant bioconversion employ severe and harmful chemical/physical pretreatments raising biofuel cost production and environmental degradation. Replacing these methods with co-cultivated enzymatic cocktails is an alternative. Here we propose a pretreatment for sugarcane bagasse using a multi-enzymatic cocktail from the co-cultivation of four Aspergillus nidulans recombinant strains. The co-cultivation resulted in the simultaneous production of GH51 arabinofuranosidase (AbfA), GH11 endo-1,4-xylanase (XlnA), GH43 endo-1,5-arabinanase (AbnA) and GH12 xyloglucan specific endo-β-1,4-glucanase (XegA). This core set of recombinant enzymes was more efficient than the alternative alkaline method in maintaining the cellulose integrity and exposing this cellulose to the following saccharification process. Thermogravimetric and differential thermal analysis revealed residual byproducts on the alkali pretreated biomass, which were not found in the enzymatic pretreatment. Therefore, the enzymatic pretreatment was residue-free and seemed to be more efficient than the applied alkaline method, which makes it suitable for bioethanol production. PMID:27199917

  11. Characterization of an inducible expression system in Aspergillus nidulans using alcA and tubulin-coding genes.

    Science.gov (United States)

    Waring, R B; May, G S; Morris, N R

    1989-06-30

    Plasmids have been constructed in which expression of a gene can be placed under the control of the inducible promoter of the alcA gene encoding alcohol dehydrogenase I in Aspergillus nidulans. Simplified shuttle vectors carrying pyr4 which complements pyrG89 mutations have also been constructed. These are based on pUC19 and retain alpha-peptide expression. The beta-tubulin genes, tubC and benA, have been placed under the control of alcA and their expression studied. Levels of expression can be assayed phenotypically because increased synthesis of beta-tubulin inhibits vegetative growth. Sensitivity of asexual spore formation to the anti-microtubule drug benomyl provides a means of detecting very low levels of expression of the chimeric genes. Glucose almost completely represses the chimeric genes. Induction is rapid and is maximal within an hour. When a strain carrying seven copies of an alcA::tubC gene fusion was grown under inducing conditions, 6.5% of total sulfate labelled protein consisted of tubC product. Cyclopentanone was the most potent inducer of the chimeric genes on solid media but it also partially inhibited growth. Chimeric alcA::tubC and alcA::benA genes were expressed to very similar levels despite the fact that tubC utilizes many rare codons.

  12. Co-cultivation of Aspergillus nidulans recombinant strains produces an enzymatic cocktail as alternative to alkaline sugarcane bagasse pretreatment

    Directory of Open Access Journals (Sweden)

    Matheus Sanita Lima

    2016-04-01

    Full Text Available Plant materials represent a strategic energy source because they can give rise to sustainable biofuels through the fermentation of their carbohydrates. A clear example of a plant-derived biofuel resource is the sugar cane bagasse exhibiting 60 % - 80 % of fermentable sugars in its composition. However, the current methods of plant bioconversion employ severe and harmful chemical/physical pretreatments raising biofuel cost production and environmental degradation. Replacing these methods with co-cultivated enzymatic cocktails is an alternative. Here we propose a pretreatment for sugarcane bagasse using a multi-enzymatic cocktail from the co-cultivation of four Aspergillus nidulans recombinant strains. The co-cultivation resulted in the simultaneous production of GH51 arabinofuranosidase (AbfA, GH11 endo-1,4-xylanase (XlnA, GH43 endo-1,5-arabinanase (AbnA and GH12 xyloglucan specific endo-β-1,4-glucanase (XegA. This core set of recombinant enzymes was more efficient than the alternative alkaline method in maintaining the cellulose integrity and exposing this cellulose to the following saccharification process. Thermogravimetric and differential thermal analysis revealed residual byproducts on the alkali pretreated biomass, which were not found in the enzymatic pretreatment. Therefore, the enzymatic pretreatment was residue-free and seemed to be more efficient than the applied alkaline method, which makes it suitable for bioethanol production.

  13. Co-cultivation of Aspergillus nidulans Recombinant Strains Produces an Enzymatic Cocktail as Alternative to Alkaline Sugarcane Bagasse Pretreatment.

    Science.gov (United States)

    Lima, Matheus S; Damasio, André R de L; Crnkovic, Paula M; Pinto, Marcelo R; da Silva, Ana M; da Silva, Jean C R; Segato, Fernando; de Lucas, Rosymar C; Jorge, João A; Polizeli, Maria de L T de M

    2016-01-01

    Plant materials represent a strategic energy source because they can give rise to sustainable biofuels through the fermentation of their carbohydrates. A clear example of a plant-derived biofuel resource is the sugar cane bagasse exhibiting 60-80% of fermentable sugars in its composition. However, the current methods of plant bioconversion employ severe and harmful chemical/physical pretreatments raising biofuel cost production and environmental degradation. Replacing these methods with co-cultivated enzymatic cocktails is an alternative. Here we propose a pretreatment for sugarcane bagasse using a multi-enzymatic cocktail from the co-cultivation of four Aspergillus nidulans recombinant strains. The co-cultivation resulted in the simultaneous production of GH51 arabinofuranosidase (AbfA), GH11 endo-1,4-xylanase (XlnA), GH43 endo-1,5-arabinanase (AbnA) and GH12 xyloglucan specific endo-β-1,4-glucanase (XegA). This core set of recombinant enzymes was more efficient than the alternative alkaline method in maintaining the cellulose integrity and exposing this cellulose to the following saccharification process. Thermogravimetric and differential thermal analysis revealed residual byproducts on the alkali pretreated biomass, which were not found in the enzymatic pretreatment. Therefore, the enzymatic pretreatment was residue-free and seemed to be more efficient than the applied alkaline method, which makes it suitable for bioethanol production. PMID:27199917

  14. Efeito da Aloe arborescens Miller e da Aloe barbadensis Miller sobre o desenvolvimento vegetativo em Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    A. P. BERTI

    2015-12-01

    Full Text Available RESUMOA pesquisa de produtos naturais benéficos à saúde humana vem crescendo nos últimos 20 anos. Considerando que as plantas de Aloe são amplamente utilizadas pela população humana, em geral de maneira terapêutica, o objetivo deste estudo foi avaliar os efeitos de Aloearborescens Miller e Aloe barbadensis Miller, sobre o desenvolvimento vegetativo de linhagens normais e mutantes de Aspergillus nidulans. Conídios da linhagem biA1methG1, MSE e CLB3 de A. nidulans, foram inoculados em meio completo sem (Controle e com extratos das duas espécies incubados por 2, 4, 6 e 8 horas a 37ºC, no escuro. Foi analisado em microscópio óptico, 200 conídios de cada tratamento. Para o desenvolvimento das colônias, as linhagens foram inoculadas no centro das placas juntamente com o meio de cultura sólido e sobre a membrana de diálise, visando a medição do diâmetro e do peso. A análise estatística foi baseada no teste de Tukey e todos os procedimentos experimentais foram conduzidos em triplicata. Todas as linhagens apresentaram interferências positivas quando expostas às plantas de Aloe, porém, de maneira variada. Ambas as espécies aceleraram a germinação em todas as linhagens testadas e atuaram na redução significativa de conídios mortos e/ou malformados. Em relação ao desenvolvimento vegetativo, todos os dados referentes ao peso úmido e diâmetro corrigido dos tratamentos demonstraram progressos, contudo, a razão diâmetro/peso apresentou somente na linhagem MSE, ação favorável dos tratamentos naturais. As informações deste estudo sugerem benefícios de A. arborescens e A. barbadensis, justificando a importância e continuidade da investigação, para melhor elucidar os mecanismos de ação dessas plantas.

  15. Immobilization and Biochemical Properties of the Enantioselective Recombinant NStcI Esterase of Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Carolina Peña-Montes

    2013-01-01

    Full Text Available The recombinant NStcI A. nidulans esterase was adsorbed on Accurel MP1000, where protein yield and immobilization efficiency were 42.48% and 81.94%, respectively. Storage stability test at 4°C and RT showed 100% of residual activity after 40 days at both temperatures. The biocatalyst retains more than 70% of its initial activity after 3 cycles of repeated use. Biochemical properties of this new biocatalyst were obtained. Maximum activity was achieved at pH 11 and 30°C, while the best stability was observed with the pH between 9 and 11 at 40°C. NStcI thermostability was increased after immobilization, as it retained 47.5% of its initial activity after 1 h at 60°C, while the free enzyme under the same conditions displayed no activity. NStcI preserved 70% of its initial activity in 100% hexane after 72 h. Enzymatic kinetic resolution of (R,S-1-phenylethanol was chosen as model reaction, using vinyl acetate as acyl donor. After optimization of reaction parameters, the highest possible conversion (42% was reached at 37°C, aw of 0.07, and 120 h of bioconversion in hexane with an enantiomeric excess of 71.7%. NStcI has selectivity for (R-enantiomer. The obtained E value (31.3 is in the range considered useful to resolve enantiomeric mixtures.

  16. Quantitative Analysis of the Relative Transcript Levels of ABC Transporter Atr Genes in Aspergillus nidulans by Real-Time Reverse Transcription-PCR Assay

    OpenAIRE

    Pizeta Semighini, Camile; Marins, Mozart; Goldman, Maria Helena S.; Goldman, Gustavo Henrique

    2002-01-01

    The development of assays for quantitative analysis of the relative transcript levels of ABC transporter genes by real-time reverse transcription-PCR (RT-PCR) might provide important information about multidrug resistance in filamentous fungi. Here, we evaluate the potential of real-time RT-PCR to quantify the relative transcript levels of ABC transporter Atr genes from Aspergillus nidulans. The AtrA to AtrD genes showed different and higher levels in the presence of structurally unrelated dr...

  17. A mutation in the converter subdomain of Aspergillus nidulans MyoB blocks constriction of the actomyosin ring in cytokinesis.

    Science.gov (United States)

    Hill, Terry W; Jackson-Hayes, Loretta; Wang, Xiao; Hoge, Brianna L

    2015-02-01

    We have identified a mutant allele of the Aspergillus nidulans homologue of myosin II (myoB; AN4706), which prevents normal septum formation. This is the first reported myosin II mutation in a filamentous fungus. Strains expressing the myoB(G843D) allele produce mainly aberrant septa at 30 °C and are completely aseptate at temperatures above 37 °C. Conidium formation is greatly reduced at 30 °C and progressively impaired with increasing temperature. Sequencing of the myoB(G843D) allele identified a point mutation predicted to result in a glycine-to-aspartate amino acid substitution at residue 843 in the myosin II converter domain. This residue is conserved in all fungal, plant, and animal myosin sequences that we have examined. The mutation does not prevent localization of the myoB(G843D) gene product to contractile rings, but it does block ring constriction. MyoB(G843D) rings at sites of abortive septation disassemble after an extended period and dissipate into the cytoplasm. During contractile ring formation, both wild type and mutant MyoB::GFP colocalize with actin--an association that begins at the pre-ring "string" stage. Down-regulation of wild-type myoB expression under control of the alcA promoter blocks septation but does not prevent actin from aggregating at putative septation sites--the actin rings, however, do not fully coalesce. Both septation and targeting of MyoB are blocked by disruption of filamentous actin using latrunculin B. We propose a model in which myosin assembly at septation sites depends upon the presence of F-actin, but assembly of the actin component of contractile rings depends upon normal levels of myosin only for the final stages of ring compaction.

  18. Characterisation of Aspergillus niger prolyl aminopeptidase

    NARCIS (Netherlands)

    Basten, E.J.W.; Moers, A.P.H.A.; Ooyen, van A.J.J.; Schaap, P.J.

    2005-01-01

    We have cloned a gene (papA) that encodes a prolyl aminopeptidase from Aspergillus niger. Homologous genes are present in the genomes of the Eurotiales A. nidulans, A. fumigatus and Talaromyces emersonii, but the gene is not present in the genome of the yeast Saccharomyces cerevisiae. Cell extracts

  19. Aspergillus nidulans as a platform for discovery and characterization of complex biosynthetic pathways

    DEFF Research Database (Denmark)

    Anyaogu, Diana Chinyere

    as a model organism for a range of research disciplines and manygenetic engineering tools are available for working in this organism. This PhD study therefore employed A.nidulans as a model system to address the following on two aspects: 1) Developing A. nidulans as aplatform for pathway discovery...... of secondary metabolites and 2) Developing A. nidulans as a model systemfor protein production with human-like glycan structure.  The first part of this study resulted in the development of a method for the transfer and expression ofintact biosynthetic gene clusters to A. nidulans to facilitate pathway......Filamentous fungi produce a wide range of bioactive compounds, classified as secondary metabolites,which have the potential to be used as pharmaceuticals, insecticides, fungicides and food additives.Secondary metabolites also include mycotoxins, which are produced by fungi that contaminate food...

  20. Putative PmrA and PmcA are important for normal growth, morphogenesis and cell wall integrity, but not for viability in Aspergillus nidulans.

    Science.gov (United States)

    Jiang, Hechun; Liu, Feifei; Zhang, Shizhu; Lu, Ling

    2014-11-01

    P-type Ca(2+)-transporting ATPases are Ca(2+) pumps, extruding cytosolic Ca(2+) to the extracellular environment or the intracellular Ca(2+) store lumens. In budding yeast, Pmr1 (plasma membrane ATPase related), and Pmc1 (plasma membrane calcium-ATPase) cannot be deleted simultaneously for it to survive in standard medium. Here, we deleted two putative Ca(2+) pumps, designated AnPmrA and AnPmcA, from Aspergillus nidulans, and obtained the mutants ΔanpmrA and ΔanpmcA, respectively. Then, using ΔanpmrA as the starting strain, the promoter of its anpmcA was replaced with the alcA promoter to secure the mutant ΔanpmrAalcApmcA or its anpmcA was deleted completely to produce the mutant ΔanpmrAΔpmcA. Different from the case in Saccharomyces cerevisiae, double deletion of anpmrA and anpmcA was not lethal in A. nidulans. In addition, deletion of anpmrA and/or anpmcA had produced growth defects, although overexpression of AnPmc1 in ΔanpmrAalcApmcA could not restore the growth defects that resulted from the loss of AnPmrA. Moreover, we found AnPmrA was indispensable for maintenance of normal morphogenesis, especially in low-Ca(2+)/Mn(2+) environments. Thus, our findings suggest AnPmrA and AnPmcA might play important roles in growth, morphogenesis and cell wall integrity in A. nidulans in a different way from that in yeasts.

  1. Aspergillus nidulans class V and VI chitin synthases CsmA and CsmB, each with a myosin motor-like domain, perform compensatory functions that are essential for hyphal tip growth.

    Science.gov (United States)

    Takeshita, Norio; Yamashita, Shuichi; Ohta, Akinori; Horiuchi, Hiroyuki

    2006-03-01

    The polarized synthesis of cell wall components such as chitin is essential for the hyphal tip growth of filamentous fungi. The actin cytoskeleton is known to play important roles in the determination of hyphal polarity in Aspergillus nidulans. Previously, we suggested that CsmA, a chitin synthase with a myosin motor-like domain (MMD), was involved in polarized chitin synthesis in a manner dependent on the interaction between the MMD and the actin cytoskeleton. The genome database indicates that A. nidulans possesses another gene encoding another chitin synthase with an MMD. In this study, we characterized this gene, which we designated csmB. The csmB null mutants examined were viable, although they exhibited defective phenotypes, including the formation of balloons and intrahyphal hyphae and the lysis of subapical regions, which were similar to those obtained with csmA null mutants. Moreover, csmA csmB double null mutants were not viable. Mutants in which csmB was deleted and the expression of csmA was under the control of the alcA promoter were viable but severely impaired in terms of hyphal growth under alcA-repressing conditions. We revealed that CsmB with three copies of a FLAG epitope tag localized at the hyphal tips and forming septa, and that the MMD of CsmB was able to bind to actin filaments in vitro. These results suggest that CsmA and CsmB perform compensatory functions that are essential for hyphal tip growth.

  2. The Aspergillus Genome Database, a curated comparative genomics resource for gene, protein and sequence information for the Aspergillus research community.

    Science.gov (United States)

    Arnaud, Martha B; Chibucos, Marcus C; Costanzo, Maria C; Crabtree, Jonathan; Inglis, Diane O; Lotia, Adil; Orvis, Joshua; Shah, Prachi; Skrzypek, Marek S; Binkley, Gail; Miyasato, Stuart R; Wortman, Jennifer R; Sherlock, Gavin

    2010-01-01

    The Aspergillus Genome Database (AspGD) is an online genomics resource for researchers studying the genetics and molecular biology of the Aspergilli. AspGD combines high-quality manual curation of the experimental scientific literature examining the genetics and molecular biology of Aspergilli, cutting-edge comparative genomics approaches to iteratively refine and improve structural gene annotations across multiple Aspergillus species, and web-based research tools for accessing and exploring the data. All of these data are freely available at http://www.aspgd.org. We welcome feedback from users and the research community at aspergillus-curator@genome.stanford.edu.

  3. Quantitative Analysis of the Relative Transcript Levels of ABC Transporter Atr Genes in Aspergillus nidulans by Real-Time Reverse Transcription-PCR Assay

    Science.gov (United States)

    Pizeta Semighini, Camile; Marins, Mozart; Goldman, Maria Helena S.; Goldman, Gustavo Henrique

    2002-01-01

    The development of assays for quantitative analysis of the relative transcript levels of ABC transporter genes by real-time reverse transcription-PCR (RT-PCR) might provide important information about multidrug resistance in filamentous fungi. Here, we evaluate the potential of real-time RT-PCR to quantify the relative transcript levels of ABC transporter Atr genes from Aspergillus nidulans. The AtrA to AtrD genes showed different and higher levels in the presence of structurally unrelated drugs, such as camptothecin, imazalil, itraconazole, hygromycin, and 4-nitroquinoline oxide. We also verified the relative transcript levels of the Atr genes in the A. nidulans imazalil-resistant mutants. These genes displayed a very complex pattern in different ima genetic backgrounds. The imaB mutant has higher basal transcript levels of AtrB and -D than those of the wild-type strain. The levels of these two genes are comparable when the imaB mutant is grown in the presence and absence of imazalil. The imaC, -D, and -H mutants have higher basal levels of AtrA than that of the wild type. The same behavior is observed for the relative transcript levels of AtrB in the imaG mutant background. PMID:11872487

  4. An ortholog of farA of Aspergillus nidulans is implicated in the transcriptional activation of genes involved in fatty acid utilization in the yeast Yarrowia lipolytica

    Energy Technology Data Exchange (ETDEWEB)

    Poopanitpan, Napapol; Kobayashi, Satoshi; Fukuda, Ryouichi; Horiuchi, Hiroyuki [Department of Biotechnology, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657 (Japan); Ohta, Akinori, E-mail: aaohta@mail.ecc.u-tokyo.ac.jp [Department of Biotechnology, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657 (Japan)

    2010-11-26

    Research highlights: {yields} POR1 is a Yarrowia lipolytica ortholog of farA involved in fatty acid response in A. nidulans. {yields} Deletion of POR1 caused growth defects on fatty acids. {yields} {Delta}por1 strain exhibited defects in the induction of genes involved in fatty acid utilization. -- Abstract: The yeast Yarrowia lipolytica effectively utilizes hydrophobic substrates such as fatty acids and n-alkanes. To identify a gene(s) regulating fatty acid utilization in Y. lipolytica, we first studied homologous genes to OAF1 and PIP2 of Saccharomyces cerevisiae, but their disruption did not change growth on oleic acid at all. We next characterized a Y. lipolytica gene, POR1 (primary oleate regulator 1), an ortholog of farA encoding a transcriptional activator that regulates fatty acid utilization in Aspergillus nidulans. The deletion mutant of POR1 was defective in the growth on various fatty acids, but not on glucose, glycerol, or n-hexadecane. It exhibited slight defect on n-decane. The transcriptional induction of genes involved in {beta}-oxidation and peroxisome proliferation by oleate was distinctly diminished in the {Delta}por1 strains. These data suggest that POR1 encodes a transcriptional activator widely regulating fatty acid metabolism in Y. lipolytica.

  5. A protein kinase C-encoding gene, pkcA, is essential to the viability of the filamentous fungus Aspergillus nidulans.

    Science.gov (United States)

    Ichinomiya, Masayuki; Uchida, Hirotaka; Koshi, Yukako; Ohta, Akinori; Horiuchi, Hiroyuki

    2007-11-01

    A protein kinase C (PKC)-encoding gene (pkcA) was isolated from the filamentous fungus Aspergillus nidulans. Although we attempted to isolate pkcA deletion mutants, we obtained only heterokaryons that had both DeltapkcA and pkcA(+) nuclei. Conidia produced by the heterokaryon germinated. The germ tubes, however, lysed frequently and no colony formation was observed, indicating that the pkcA gene is essential to the viability of A. nidulans. We constructed conditional mutants (alcA(p)-pkcA mutants) that expressed pkcA under the control of the alcA promoter (alcA(p)). Under alcA(p)-repressing conditions, their colonies were smaller than those of the wild-type strains and their hyphae lysed frequently. These phenotypes were not remedied under moderate- or high-osmolarity conditions; the growth defect deteriorated further under the latter. Under alcA(p)-inducing conditions, the alcA(p)-pkcA mutants also showed growth-sensitivity to cell wall destabilizing agents. These results indicate that pkcA plays an important role in the maintenance of cell integrity.

  6. Depletion of Aspergillus nidulans cotA causes a severe polarity defect which is not suppressed by the nuclear migration mutation nudA2.

    Science.gov (United States)

    Johns, Sarah Anne; Leeder, Abigail Claire; Safaie, Mehran; Turner, Geoffrey

    2006-06-01

    The Aspergillus nidulans homologue of Neurospora crassa cot-1, cotA, encoding a member of the NDR protein kinase family, has been cloned and expressed under the control of the conditional alcA promoter. Depletion of CotA by repression of the alcA promoter led to a severe growth defect accompanied by loss of polarity. Germlings show greatly enlarged volume of the spores and hyphae, accompanied by an increase in number of nuclei per compartment, though the nucleus/volume ratio is not significantly altered. The depleted CotA phenotype was not suppressed by a nuclear migration mutation nudA2. Double mutants showed an additive, defective phenotype, unlike the suppression of the cot-1 ts mutation by ropy mutations seen in N. crassa, suggesting a different relationship between nuclear migration and the cot signalling pathway in A. nidulans. A functional CotA-GFP fusion protein was found in punctate regions of fluorescence similar to the distribution reported for human NDR2, and as a cap at the hyphal tip.

  7. Analysis of the Aspergillus nidulans thaumatin-like cetA gene and evidence for transcriptional repression of pyr4 expression in the cetA-disrupted strain.

    Science.gov (United States)

    Greenstein, Shulamit; Shadkchan, Yona; Jadoun, Jeries; Sharon, Chaim; Markovich, Sarit; Osherov, Nir

    2006-01-01

    The asexual spore or conidium plays a critical role in the life cycle of many filamentous fungi. However, the process of conidial germination remains surprisingly obscure. To better understand this process at the molecular level we characterized the Aspergillus nidulans cetA gene which is uniquely transcribed in conidiating cultures and whose transcript is significantly enriched in mature conidia. CetA is a member of a novel family of fungal genes of unknown function with homology to plant thaumatin-like (PR-5) defense proteins. We demonstrate by Northern analysis that cetA is a glucose-repressible gene. Transcriptional repression is dependent on the presence of protein kinase A. Western analysis indicates that the CETA protein is absent from conidia but is highly expressed during the first 6h of germination and is secreted into the medium. Disruption of the cetA gene seemingly results in delayed germination, slow growth, abnormal hyphal branching, and cell-wall defects. However, further analysis shows that the mutant phenotype is the result of glucose-dependent transcriptional repression of the pyr4 selectable marker used to disrupt the cetA gene. This is the first time that repression of a selectable marker ("position effect") has been reported in A. nidulans, a finding that may well be of significance in the analysis and interpretation of mutant phenotypes in this organism. PMID:16376592

  8. The selective expression of carbonic anhydrase genes of Aspergillus nidulans in response to changes in mineral nutrition and CO2 concentration.

    Science.gov (United States)

    Xiao, Leilei; Lian, Bin; Dong, Cuiling; Liu, Fanghua

    2016-02-01

    Carbonic anhydrase (CA) plays an important role in the formation and evolution of life. However, to our knowledge, there has been no report on CA isoenzyme function differentiation in fungi. Two different CA gene sequences in Aspergillus nidulans with clear genetic background provide us a favorable basis for studying function differentiation of CA isoenzymes. Heterologously expressed CA1 was used to test its weathering ability on silicate minerals and real-time quantitative PCR was used to detect expression of the CA1 and CA2 genes at different CO2 concentrations and in the presence of different potassium sources. The northern blot method was applied to confirm the result of CA1 gene expression. Heterologously expressed CA1 significantly promoted dissolution of biotite and wollastonite, and CA1 gene expression increased significantly in response to soluble K-deficiency. The northern blot test further showed that CA1 participated in K-feldspar weathering. In addition, the results showed that CA2 was primary involved in adapting to CO2 concentration change. Taken together, A. nidulans can choose different CA to meet their survival needs, which imply that some environmental microbes have evolved different CAs to adapt to changes in CO2 concentration and acquire mineral nutrition so that they can better adapt to environmental changes. Inversely, their adaption may impact mineral weathering and/or CO2 concentration, and even global change.

  9. Protoplast isolation from cultured lichen Usnea ghattensis, their fusion with protoplasts of Aspergillus nidulans, fusant regeneration and production of usnic acid.

    Science.gov (United States)

    Behera, B C; Sonone, A; Makhija, U

    2009-09-01

    Protoplasts isolated from the mycobiont of a cultured lichen Usnea ghattensis were fused with protoplasts of the fungus Aspergillus nidulans in order to increase the growth rate of the cultured lichen mycobiont in vitro. The maximum protoplast yield (102 x 10(4)/g fresh cell mass) was reached in citrate buffer with 50 mmol/L 2-sulfanylethanol ('2-mercaptoethanol') containing 0.1 % Novozym after 1.5 h at pH 5 and protoplasts. The fused protoplasts were regenerated after transfer to malt extract-yeast extract medium and produced, after a 45-d cultivation, a fresh cell mass of 0.232 g (from starting 0.3 g) along with the lichen substance usnic acid. PMID:19937214

  10. Analysis and prediction of gene splice sites in four Aspergillus genomes

    DEFF Research Database (Denmark)

    Wang, Kai; Ussery, David; Brunak, Søren

    2009-01-01

    , splice site prediction program called NetAspGene, for the genus Aspergillus. Gene sequences from Aspergillus fumigatus, the most common mould pathogen, were used to build and test our model. Compared to many animals and plants, Aspergillus contains smaller introns; thus we have applied a larger window...... better splice site prediction than other available tools. NetAspGene will be very helpful for the study in Aspergillus splice sites and especially in alternative splicing. A webpage for NetAspGene is publicly available at http://www.cbs.dtu.dk/services/NetAspGene....... size on single local networks for training, to cover both donor and acceptor site information. We have applied NetAspGene to other Aspergilli, including Aspergillus nidulans, Aspergillus oryzae, and Aspergillus niger. Evaluation with independent data sets reveal that NetAspGene performs substantially...

  11. A trispecies Aspergillus microarray: Comparative transcriptomics of three Aspergillus species

    DEFF Research Database (Denmark)

    Andersen, Mikael Rørdam; Vongsangnak, Wanwipa; Panagiotou, Gianni;

    2008-01-01

    The full-genome sequencing of the filamentous fungi Aspergillus nidulans, Aspergillus niger, and Aspergillus oryzae has opened possibilities for studying the cellular physiology of these fungi on a systemic level. As a tool to explore this, we are making available an Affymetrix GeneChip developed...... data identified 23 genes to be a conserved response across Aspergillus sp., including the xylose transcriptional activator XlnR. A promoter analysis of the up-regulated genes in all three species indicates the conserved XInR-binding site to be 5'-GGNTAAA-3'. The composition of the conserved gene......-set suggests that xylose acts as a molecule, indicating the presence of complex carbohydrates such as hemicellulose, and triggers an array of degrading enzymes. With this case example, we present a validated tool for transcriptome analysis of three Aspergillus species and a methodology for conducting cross...

  12. Aspergillus nidulans Synthesize Insect Juvenile Hormones upon Expression of a Heterologous Regulatory Protein and in Response to Grazing by Drosophila melanogaster Larvae

    DEFF Research Database (Denmark)

    Nielsen, Morten Thrane; Klejnstrup, Marie Louise; Rohlfs, Marko;

    2013-01-01

    Secondary metabolites are known to serve a wide range of specialized functions including communication, developmental control and defense. Genome sequencing of several fungal model species revealed that the majority of predicted secondary metabolite related genes are silent in laboratory strains,...... larvae induced synthesis of juvenile hormone in A. nidulans indicating a possible role of juvenile hormone biosynthesis in affecting fungal-insect antagonisms....

  13. GmcA is a putative glucose-methanol-choline oxidoreductase required for the induction of asexual development in Aspergillus nidulans.

    Directory of Open Access Journals (Sweden)

    Oier Etxebeste

    Full Text Available Aspergillus nidulans asexual differentiation is induced by Upstream Developmental Activators (UDAs that include the bZIP-type Transcription Factor (TF FlbB. A 2D-PAGE/MS-MS-coupled screen for proteins differentially expressed in the presence and absence of FlbB identified 18 candidates. Most candidates belong to GO term classes involved in osmotic and/or oxidative stress response. Among these, we focused on GmcA, a putative glucose-methanol-choline oxidoreductase which is upregulated in a ΔflbB background. GmcA is not required for growth since no differences were detected in the radial extension upon deletion of gmcA. However, its activity is required to induce conidiation under specific culture conditions. A ΔgmcA strain conidiates profusely under acid conditions but displays a characteristic fluffy aconidial phenotype in alkaline medium. The absence of asexual development in a ΔgmcA strain can be suppressed, on one hand, using high concentrations of non-fermentable carbon sources like glycerol, and on the other hand, when the cMyb-type UDA TF flbD is overexpressed. Overall, the results obtained in this work support a role for GmcA at early stages of conidiophore initiation.

  14. GmcA is a putative glucose-methanol-choline oxidoreductase required for the induction of asexual development in Aspergillus nidulans.

    Science.gov (United States)

    Etxebeste, Oier; Herrero-García, Erika; Cortese, Marc S; Garzia, Aitor; Oiartzabal-Arano, Elixabet; de los Ríos, Vivian; Ugalde, Unai; Espeso, Eduardo A

    2012-01-01

    Aspergillus nidulans asexual differentiation is induced by Upstream Developmental Activators (UDAs) that include the bZIP-type Transcription Factor (TF) FlbB. A 2D-PAGE/MS-MS-coupled screen for proteins differentially expressed in the presence and absence of FlbB identified 18 candidates. Most candidates belong to GO term classes involved in osmotic and/or oxidative stress response. Among these, we focused on GmcA, a putative glucose-methanol-choline oxidoreductase which is upregulated in a ΔflbB background. GmcA is not required for growth since no differences were detected in the radial extension upon deletion of gmcA. However, its activity is required to induce conidiation under specific culture conditions. A ΔgmcA strain conidiates profusely under acid conditions but displays a characteristic fluffy aconidial phenotype in alkaline medium. The absence of asexual development in a ΔgmcA strain can be suppressed, on one hand, using high concentrations of non-fermentable carbon sources like glycerol, and on the other hand, when the cMyb-type UDA TF flbD is overexpressed. Overall, the results obtained in this work support a role for GmcA at early stages of conidiophore initiation. PMID:22792266

  15. A pericentrin-related protein homolog in Aspergillus nidulans plays important roles in nucleus positioning and cell polarity by affecting microtubule organization.

    Science.gov (United States)

    Chen, Peiying; Gao, Rongsui; Chen, Shaochun; Pu, Li; Li, Pin; Huang, Ying; Lu, Ling

    2012-12-01

    Pericentrin is a large coiled-coil protein in mammalian centrosomes that serves as a multifunctional scaffold for anchoring numerous proteins. Recent studies have linked numerous human disorders with mutated or elevated levels of pericentrin, suggesting unrecognized contributions of pericentrin-related proteins to the development of these disorders. In this study, we characterized AnPcpA, a putative homolog of pericentrin-related protein in the model filamentous fungus Aspergillus nidulans, and found that it is essential for conidial germination and hyphal development. Compared to the hyphal apex localization pattern of calmodulin (CaM), which has been identified as an interactive partner of the pericentrin homolog, GFP-AnPcpA fluorescence dots are associated mainly with nuclei, while the accumulation of CaM at the hyphal apex depends on the function of AnPcpA. In addition, the depletion of AnPcpA by an inducible alcA promoter repression results in severe growth defects and abnormal nuclear segregation. Most interestingly, in mature hyphal cells, knockdown of pericentrin was able to significantly induce changes in cell shape and cytoskeletal remodeling; it resulted in some enlarged compartments with condensed nuclei and anucleate small compartments as well. Moreover, defects in AnPcpA significantly disrupted the microtubule organization and nucleation, suggesting that AnPcpA may affect nucleus positioning by influencing microtubule organization.

  16. Specific binding sites in the alcR and alcA promoters of the ethanol regulon for the CREA repressor mediating carbon catabolite repression in Aspergillus nidulans.

    Science.gov (United States)

    Kulmburg, P; Mathieu, M; Dowzer, C; Kelly, J; Felenbok, B

    1993-03-01

    The CREA repressor responsible for carbon catabolite repression in Aspergillus nidulans represses the transcription of the ethanol regulon. The N-terminal part of the CREA protein encompassing the two zinc fingers (C2H2 class family) and an alanine-rich region was expressed in Escherichia coli as a fusion protein with glutathione-S-transferase. Our results show that CREA is a DNA-binding protein able to bind to the promoters of both the specific trans-acting gene, alcR, and of the structural gene, alcA, encoding the alcohol dehydrogenase I. DNase I protection footprinting experiments revealed several specific binding sites in the alcR and in the alcA promoters having the consensus sequence 5'-G/CPyGGGG-3'. The disruption of one of these CREA-binding sites in the alcR promoter overlapping the induction target for the trans-activator ALCR results in a partially derepressed alc phenotype and derepressed alcR transcription, showing that this binding site is functional in vivo. Our data suggest that CREA represses the ethanol regulon by a double lock mechanism repressing both the trans-acting gene, alcR, and the structural gene, alcA.

  17. Arabidopsis and Brachypodium distachyon transgenic plants expressing Aspergillus nidulans acetylesterases have decreased degree of polysaccharide acetylation and increased resistance to pathogens.

    Science.gov (United States)

    Pogorelko, Gennady; Lionetti, Vincenzo; Fursova, Oksana; Sundaram, Raman M; Qi, Mingsheng; Whitham, Steven A; Bogdanove, Adam J; Bellincampi, Daniela; Zabotina, Olga A

    2013-05-01

    The plant cell wall has many significant structural and physiological roles, but the contributions of the various components to these roles remain unclear. Modification of cell wall properties can affect key agronomic traits such as disease resistance and plant growth. The plant cell wall is composed of diverse polysaccharides often decorated with methyl, acetyl, and feruloyl groups linked to the sugar subunits. In this study, we examined the effect of perturbing cell wall acetylation by making transgenic Arabidopsis (Arabidopsis thaliana) and Brachypodium (Brachypodium distachyon) plants expressing hemicellulose- and pectin-specific fungal acetylesterases. All transgenic plants carried highly expressed active Aspergillus nidulans acetylesterases localized to the apoplast and had significant reduction of cell wall acetylation compared with wild-type plants. Partial deacetylation of polysaccharides caused compensatory up-regulation of three known acetyltransferases and increased polysaccharide accessibility to glycosyl hydrolases. Transgenic plants showed increased resistance to the fungal pathogens Botrytis cinerea and Bipolaris sorokiniana but not to the bacterial pathogens Pseudomonas syringae and Xanthomonas oryzae. These results demonstrate a role, in both monocot and dicot plants, of hemicellulose and pectin acetylation in plant defense against fungal pathogens.

  18. Utilização de linhagens diplóides uvsH//uvsH de Aspergillus nidulans (Ascomycetes para a avaliação do potencial recombinagênico de agentes químicos e físicos uvsH//uvsH diploid strain favors an efficient method to evaluate the recombinagenic effect of chemical and physical agents in Aspergillus nidulans (Ascomycetes

    Directory of Open Access Journals (Sweden)

    Francielle Baptista

    2001-05-01

    Full Text Available O ascomiceto Aspergillus nidulans apresenta-se como um excelente sistema para o estudo da recombinação somática, por passar grande parte de seu ciclo celular em G2 e por apresentar mutações uvs que promovem aumento das freqüências normais de recombinação mitótica (uvsF e uvsH. O presente trabalho teve como objetivo obter uma nova linhagem diplóide de A. nidulans, com características apropriadas para estudos da recombinagênese, tais como: hetererozigose para marcadores nutricionais e de coloração de conidios e homozigose para a mutação uvsH. A maior sensibilidade do diplóide uvsH//uvsH no monitoramento de eventos de recombinação mitótica foi demonstrada através dos mais altos índices de recombinação mitótica espontânea por ele apresentados, em comparação com o diplóide uvsH+//uvsH +. A nova linhagem apresenta-se como uma ferramenta versátil, podendo ser utilizada em diferentes estudos relacionados à recombinação mitótica em A. nidulansAscomycete Aspergillus nidulans is an excellent system for mitotic crossing-over studies. This is due to the fact that much of its cell cycle is passed in G2 and presents uvs mutations that increase frequencies of normal mitotic recombinations (uvsF and uvsH. The aim of this research was to obtain a new diploid strain of A. nidulans with proper characteristics for recombinagenesis investigations, or rather, heterozygous for nutritional markers and conidia coloration and homozygous for uvsH mutation. Higher sensitivity of diploid uvsH//uvsH in the monitoring of mitotic recombination events was shown by higher indexes of the diploid’s spontaneous mitotic recombination when compared with diploid uvsH+//uvsH +. New strain is a versatile tool that may be used in different studies on mitotic recombination in A. nidulans

  19. The Set1/COMPASS histone H3 methyltransferase helps regulate mitosis with the CDK1 and NIMA mitotic kinases in Aspergillus nidulans.

    Science.gov (United States)

    Govindaraghavan, Meera; Anglin, Sarah Lea; Osmani, Aysha H; Osmani, Stephen A

    2014-08-01

    Mitosis is promoted and regulated by reversible protein phosphorylation catalyzed by the essential NIMA and CDK1 kinases in the model filamentous fungus Aspergillus nidulans. Protein methylation mediated by the Set1/COMPASS methyltransferase complex has also been shown to regulate mitosis in budding yeast with the Aurora mitotic kinase. We uncover a genetic interaction between An-swd1, which encodes a subunit of the Set1 protein methyltransferase complex, with NIMA as partial inactivation of nimA is poorly tolerated in the absence of swd1. This genetic interaction is additionally seen without the Set1 methyltransferase catalytic subunit. Importantly partial inactivation of NIMT, a mitotic activator of the CDK1 kinase, also causes lethality in the absence of Set1 function, revealing a functional relationship between the Set1 complex and two pivotal mitotic kinases. The main target for Set1-mediated methylation is histone H3K4. Mutational analysis of histone H3 revealed that modifying the H3K4 target residue of Set1 methyltransferase activity phenocopied the lethality seen when either NIMA or CDK1 are partially functional. We probed the mechanistic basis of these genetic interactions and find that the Set1 complex performs functions with CDK1 for initiating mitosis and with NIMA during progression through mitosis. The studies uncover a joint requirement for the Set1 methyltransferase complex with the CDK1 and NIMA kinases for successful mitosis. The findings extend the roles of the Set1 complex to include the initiation of mitosis with CDK1 and mitotic progression with NIMA in addition to its previously identified interactions with Aurora and type 1 phosphatase in budding yeast.

  20. Patterns of nucleosomal organization in the alc regulon of Aspergillus nidulans: roles of the AlcR transcriptional activator and the CreA global repressor.

    Science.gov (United States)

    Mathieu, Martine; Nikolaev, Igor; Scazzocchio, Claudio; Felenbok, Béatrice

    2005-04-01

    We have studied the chromatin organization of three promoters of the alc regulon of Aspergillus nidulans. No positioned nucleosomes are seen in the aldA (aldehyde dehydrogenase) promoter under any physiological condition tested by us. In the alcA (alcohol dehydrogenase I) and alcR (coding for the pathway-specific transcription factor) promoters, a pattern of positioned nucleosomes is seen under non-induced and non-induced repressed conditions. While each of these promoters shows a specific pattern of chromatin restructuring, in both cases induction results in loss of nucleosome positioning. Glucose repression in the presence of inducer results in a specific pattern of partial positioning in the alcA and alcR promoters. Loss of nucleosome positioning depends absolutely on the AlcR protein and it is very unlikely to be a passive result of the induction of transcription. In an alcR loss-of-function background and in strains carrying mutations of the respective AlcR binding sites of the alcA and alcR promoters, nucleosomes are fully positioned under all growth conditions. Analysis of mutant AlcR proteins establishes that all domains needed for transcriptional activation and chromatin restructuring are included within the first 241 residues. The results suggest a two-step process, one step resulting in chromatin restructuring, a second one in transcriptional activation. Partial positioning upon glucose repression shows a specific pattern that depends on the CreA global repressor. An alcR loss-of-function mutation is epistatic to a creA loss-of-function mutation, showing that AlcR does not act by negating a nucleosome positioning activity of CreA.

  1. Specific binding sites for the activator protein, ALCR, in the alcA promoter of the ethanol regulon of Aspergillus nidulans.

    Science.gov (United States)

    Kulmburg, P; Judewicz, N; Mathieu, M; Lenouvel, F; Sequeval, D; Felenbok, B

    1992-10-15

    ALCR is the specific activator of the Aspergillus nidulans ethanol-utilization pathway, mediating the induction of its own transcription and that of the structural genes alcA and aldA, encoding respectively, alcohol dehydrogenase I and aldehyde dehydrogenase. ALCR is a DNA binding protein in which 6 cysteines are coordinated in a zinc binuclear cluster. This domain was fused to glutathione-S-transferase (GST) and isolated as a GST-ALCR(7-58*) fusion protein from Escherichia coli. Mobility shift assays showed that the ALCR fusion protein binds at sites upstream of the alcA promoter. DNaseI protection footprinting experiments revealed three specific binding sites, two that are direct repeats and one that is an inverted repeat with the same half-site 5'-CCGCA-3'. The half-sites are separated by a variable number of nucleotides in both types of target. The interaction of the ALCR fusion protein with direct and inverted repeats were examined by using interference and protection footprinting assays. In both binding sites, modification of the guanines in the half-sites interfered with the formation of the DNA complex, but the adjacent ones did not. Our results suggest that the ALCR protein makes contact in the major groove of the DNA helix of the half-sites. The functionality of two out of three binding sites of the GST-ALCR protein was demonstrated after their deletion. Therefore, the region encompassing these binding sites is a cis-acting element involved in the full induction of the alcA gene.

  2. Genetic Interaction of Aspergillus nidulans galR, xlnR and araR in Regulating D-Galactose and L-Arabinose Release and Catabolism Gene Expression.

    Directory of Open Access Journals (Sweden)

    Joanna E Kowalczyk

    Full Text Available In Aspergillus nidulans, the xylanolytic regulator XlnR and the arabinanolytic regulator AraR co-regulate pentose catabolism. In nature, the pentose sugars D-xylose and L-arabinose are both main building blocks of the polysaccharide arabinoxylan. In pectin and arabinogalactan, these two monosaccharides are found in combination with D-galactose. GalR, the regulator that responds to the presence of D-galactose, regulates the D-galactose catabolic pathway. In this study we investigated the possible interaction between XlnR, AraR and GalR in pentose and/or D-galactose catabolism in A. nidulans. Growth phenotypes and metabolic gene expression profiles were studied in single, double and triple disruptant A. nidulans strains of the genes encoding these paralogous transcription factors. Our results demonstrate that AraR and XlnR not only control pentose catabolic pathway genes, but also genes of the oxido-reductive D-galactose catabolic pathway. This suggests an interaction between three transcriptional regulators in D-galactose catabolism. Conversely, GalR is not involved in regulation of pentose catabolism, but controls only genes of the oxido-reductive D-galactose catabolic pathway.

  3. Efeito antimutagênico do látex de Euphorbia tirucalli no sistema metionina em Aspergillus nidulans - DOI: 10.4025/actascibiolsci.v26i4.1531 Antimutagenic effect of the Euphorbia’s latex in Aspergillus nidulans methionine system - DOI: 10.4025/actascibiolsci.v26i4.1531

    Directory of Open Access Journals (Sweden)

    João Alencar Pamphile

    2004-04-01

    Full Text Available Muitas plantas medicinais têm sido analisadas quanto a seus potenciais antitumoral e antimutagênico. Aveloz, uma planta do gênero Euphorbia (Euphorbiaceae, tem sido utilizada popularmente na América do Sul no tratamento de úlceras, cânceres, tumores, verrugas e outras doenças. No entanto, algumas pesquisas demonstraram efeitos contrários a estes descritos. Devido a estes resultados contraditórios, o objetivo deste trabalho foi avaliar o potencial antimutagênico da Euphorbia tirucalli utilizando o sistema metionina em Aspergillus nidulans. Duas concentrações do látex - 0,1% e 0,2% (v/v - foram usadas no tratamento por 24 horas de conídios dormentes obtidos de colônias de cinco dias. Os resultados indicaram que o látex da Euphorbia tem potencial antimutagênico, pois tanto a concentração de 0,1% quanto a de 0,2% (v/v do látex resultaram em freqüência de mutação significativamente menor que a freqüência de mutação espontânea, obtida para o controle nestes experimentosFolk medicinal plants have been analyzed and assayed to confirm their possible antitumoral and anticarcinogenic properties. Aveloz is a plant of the genus Euphorbia (Euphorbiaceae and it has been popularly used in South America for treating ulcer, cancer, tumor, wart and other diseases. However, some researches have shown opposite effects. Due to these contradictory results, the aim of this work was to test the antimutagenic potential of Euphorbia tirucalli latex in Aspergillus nidulans methionine system. Two concentrations of the latex were used in conidia treatment: 0.1% and 0.2% (v/v. The treatment was developed by collecting quiescent conida from five days old colonies in latex solution, during 24 hours. The results have indicated that both concentrations show antimutagenic effect because the mutation frequency of the treated conidia was smaller than mutation frequency of the control

  4. Produção de xilanases por uma cepa selvagem de Aspergillus nidulans - DOI: 10.4025/actascibiolsci.v25i1.2095 Xylanase production by a wild strain of Aspergillus nidulans - DOI: 10.4025/actascibiolsci.v25i1.2095

    Directory of Open Access Journals (Sweden)

    Maria Aparecida Ferreira Costa

    2003-04-01

    Full Text Available Uma cepa selvagem de Aspergillus nidulans isolada de solo produziu xilanase isenta de atividade celulolítica quando desenvolvida em meio submerso contendo sabugo de milho como principal substrato. Produção máxima de xilanase (220 U/mL foi obtida quando a cepa foi desenvolvida em meio mineral suplementado com sabugo de milho a 3% (p/v por 6 dias. Eletroforese com SDS revelou a ocorrência de quatro iso-xilanases, com pesos moleculares de 50, 43, 20 e 18 kDa. A xilanase bruta foi resistente à precipitação com acetona, apresentando atividade ótima em pH 5.0-6.0 e temperatura entre 50º e 55ºC. A enzima exibiu grande estabilidade quando exposta a condições alcalinas, e foi estável por várias horas quando exposta a temperaturas de até 55ºC, retendo 50% e 23% de sua atividade quando aquecida por 1 h a 60 e 65ºC, respectivamenteA wild strain of Aspergillus nidulans isolated from soil produce cellulase-free xylanase activity when developed on submerged cultures using corn cob powder as the main substrate. Maximum xylanase production (220 U/mL was obtained when the strain was developed in mineral medium supplemented with 3% (w/v corn cob for 6 days. SDS-PAGE revealed the occurrence of four isoxylanases with molecular weights of 50, 43, 20 and 18 kDa. Crude xylanase was resistant to acetone precipitation with 80% of recovery. The enzyme had optimal activity at pH values between 5.0 and 6.0 and temperature between 50-55oC. The enzyme exhibited high stability under alkaline conditions and temperature up to 55oC. It retained 50% and 23% of its activity when heated for 1 h at 60 and 65oC, respectively

  5. An efficient arabinoxylan-debranching α-L-arabinofuranosidase of family GH62 from Aspergillus nidulans contains a secondary carbohydrate binding site.

    Science.gov (United States)

    Wilkens, Casper; Andersen, Susan; Petersen, Bent O; Li, An; Busse-Wicher, Marta; Birch, Johnny; Cockburn, Darrell; Nakai, Hiroyuki; Christensen, Hans E M; Kragelund, Birthe B; Dupree, Paul; McCleary, Barry; Hindsgaul, Ole; Hachem, Maher Abou; Svensson, Birte

    2016-07-01

    An α-L-arabinofuranosidase of GH62 from Aspergillus nidulans FGSC A4 (AnAbf62A-m2,3) has an unusually high activity towards wheat arabinoxylan (WAX) (67 U/mg; k cat = 178/s, K m = 4.90 mg/ml) and arabinoxylooligosaccharides (AXOS) with degrees of polymerisation (DP) 3-5 (37-80 U/mg), but about 50 times lower activity for sugar beet arabinan and 4-nitrophenyl-α-L-arabinofuranoside. α-1,2- and α-1,3-linked arabinofuranoses are released from monosubstituted, but not from disubstituted, xylose in WAX and different AXOS as demonstrated by NMR and polysaccharide analysis by carbohydrate gel electrophoresis (PACE). Mutants of the predicted general acid (Glu(188)) and base (Asp(28)) catalysts, and the general acid pK a modulator (Asp(136)) lost 1700-, 165- and 130-fold activities for WAX. WAX, oat spelt xylan, birchwood xylan and barley β-glucan retarded migration of AnAbf62A-m2,3 in affinity electrophoresis (AE) although the latter two are neither substrates nor inhibitors. Trp(23) and Tyr(44), situated about 30 Å from the catalytic site as seen in an AnAbf62A-m2,3 homology model generated using Streptomyces thermoviolaceus SthAbf62A as template, participate in carbohydrate binding. Compared to wild-type, W23A and W23A/Y44A mutants are less retarded in AE, maintain about 70 % activity towards WAX with K i of WAX substrate inhibition increasing 4-7-folds, but lost 77-96 % activity for the AXOS. The Y44A single mutant had less effect, suggesting Trp(23) is a key determinant. AnAbf62A-m2,3 seems to apply different polysaccharide-dependent binding modes, and Trp(23) and Tyr(44) belong to a putative surface binding site which is situated at a distance of the active site and has to be occupied to achieve full activity. PMID:26946172

  6. Response regulators SrrA and SskA are central components of a phosphorelay system involved in stress signal transduction and asexual sporulation in Aspergillus nidulans.

    Science.gov (United States)

    Vargas-Pérez, Itzel; Sánchez, Olivia; Kawasaki, Laura; Georgellis, Dimitris; Aguirre, Jesús

    2007-09-01

    Among eukaryotes, only slime molds, fungi, and plants contain signal transduction phosphorelay systems. In filamentous fungi, multiple sensor kinases appear to use a single histidine-containing phosphotransfer (HPt) protein to relay signals to two response regulators (RR). In Aspergillus nidulans, the RR SskA mediates activation of the mitogen-activated protein kinase SakA in response to osmotic and oxidative stress, whereas the functions of the RR SrrA were unknown. We used a genetic approach to characterize the srrA gene as a new member of the skn7/prr1 family and to analyze the roles of SrrA in the phosphorelay system composed of the RR SskA, the HPt protein YpdA, and the sensor kinase NikA. While mutants lacking the HPt protein YpdA are unviable, mutants lacking SskA (DeltasskA), SrrA (DeltasrrA), or both RR (DeltasrrA DeltasskA) are viable and differentially affected in osmotic and oxidative stress responses. Both RR are involved in osmostress resistance, but DeltasskA mutants are more sensitive to this stress, and only SrrA is required for H(2)O(2) resistance and H(2)O(2)-mediated induction of catalase CatB. In contrast, both RR are individually required for fungicide sensitivity and calcofluor resistance and for normal sporulation and conidiospore viability. The DeltasrrA and DeltasskA sporulation defects appear to be related to decreased mRNA levels of the key sporulation gene brlA. In contrast, conidiospore viability defects do not correlate with the activity of the spore-specific catalase CatA. Our results support a model in which NikA acts upstream of SrrA and SskA to transmit fungicide signals and to regulate asexual sporulation and conidiospore viability. In contrast, NikA appears dispensable for osmotic and oxidative stress signaling. These results highlight important differences in stress signal transmission among fungi and define a phosphorelay system involved in oxidative and osmotic stress, cell wall maintenance, fungicide sensitivity, asexual

  7. Functional analysis of the α-1,3-glucan synthase genes agsA and agsB in Aspergillus nidulans: agsB is the major α-1,3-glucan synthase in this fungus.

    Directory of Open Access Journals (Sweden)

    Akira Yoshimi

    Full Text Available Although α-1,3-glucan is one of the major cell wall polysaccharides in filamentous fungi, the physiological roles of α-1,3-glucan remain unclear. The model fungus Aspergillus nidulans possesses two α-1,3-glucan synthase (AGS genes, agsA and agsB. For functional analysis of these genes, we constructed several mutant strains in A. nidulans: agsA disruption, agsB disruption, and double-disruption strains. We also constructed several CagsB strains in which agsB expression was controlled by the inducible alcA promoter, with or without the agsA-disrupting mutation. The agsA disruption strains did not show markedly different phenotypes from those of the wild-type strain. The agsB disruption strains formed dispersed hyphal cells under liquid culture conditions, regardless of the agsA genetic background. Dispersed hyphal cells were also observed in liquid culture of the CagsB strains when agsB expression was repressed, whereas these strains grew normally in plate culture even under the agsB-repressed conditions. Fractionation of the cell wall based on the alkali solubility of its components, quantification of sugars, and (13C-NMR spectroscopic analysis revealed that α-1,3-glucan was the main component of the alkali-soluble fraction in the wild-type and agsA disruption strains, but almost no α-1,3-glucan was found in the alkali-soluble fraction derived from either the agsB disruption strain or the CagsB strain under the agsB-repressed conditions, regardless of the agsA genetic background. Taken together, our data demonstrate that the two AGS genes are dispensable in A. nidulans, but that AgsB is required for normal growth characteristics under liquid culture conditions and is the major AGS in this species.

  8. Functional analysis of the α-1,3-glucan synthase genes agsA and agsB in Aspergillus nidulans: agsB is the major α-1,3-glucan synthase in this fungus.

    Science.gov (United States)

    Yoshimi, Akira; Sano, Motoaki; Inaba, Azusa; Kokubun, Yuko; Fujioka, Tomonori; Mizutani, Osamu; Hagiwara, Daisuke; Fujikawa, Takashi; Nishimura, Marie; Yano, Shigekazu; Kasahara, Shin; Shimizu, Kiminori; Yamaguchi, Masashi; Kawakami, Kazuyoshi; Abe, Keietsu

    2013-01-01

    Although α-1,3-glucan is one of the major cell wall polysaccharides in filamentous fungi, the physiological roles of α-1,3-glucan remain unclear. The model fungus Aspergillus nidulans possesses two α-1,3-glucan synthase (AGS) genes, agsA and agsB. For functional analysis of these genes, we constructed several mutant strains in A. nidulans: agsA disruption, agsB disruption, and double-disruption strains. We also constructed several CagsB strains in which agsB expression was controlled by the inducible alcA promoter, with or without the agsA-disrupting mutation. The agsA disruption strains did not show markedly different phenotypes from those of the wild-type strain. The agsB disruption strains formed dispersed hyphal cells under liquid culture conditions, regardless of the agsA genetic background. Dispersed hyphal cells were also observed in liquid culture of the CagsB strains when agsB expression was repressed, whereas these strains grew normally in plate culture even under the agsB-repressed conditions. Fractionation of the cell wall based on the alkali solubility of its components, quantification of sugars, and (13)C-NMR spectroscopic analysis revealed that α-1,3-glucan was the main component of the alkali-soluble fraction in the wild-type and agsA disruption strains, but almost no α-1,3-glucan was found in the alkali-soluble fraction derived from either the agsB disruption strain or the CagsB strain under the agsB-repressed conditions, regardless of the agsA genetic background. Taken together, our data demonstrate that the two AGS genes are dispensable in A. nidulans, but that AgsB is required for normal growth characteristics under liquid culture conditions and is the major AGS in this species.

  9. Genomic islands in the pathogenic filamentous fungus Aspergillus fumigatus.

    Directory of Open Access Journals (Sweden)

    Natalie D Fedorova

    2008-04-01

    Full Text Available We present the genome sequences of a new clinical isolate of the important human pathogen, Aspergillus fumigatus, A1163, and two closely related but rarely pathogenic species, Neosartorya fischeri NRRL181 and Aspergillus clavatus NRRL1. Comparative genomic analysis of A1163 with the recently sequenced A. fumigatus isolate Af293 has identified core, variable and up to 2% unique genes in each genome. While the core genes are 99.8% identical at the nucleotide level, identity for variable genes can be as low 40%. The most divergent loci appear to contain heterokaryon incompatibility (het genes associated with fungal programmed cell death such as developmental regulator rosA. Cross-species comparison has revealed that 8.5%, 13.5% and 12.6%, respectively, of A. fumigatus, N. fischeri and A. clavatus genes are species-specific. These genes are significantly smaller in size than core genes, contain fewer exons and exhibit a subtelomeric bias. Most of them cluster together in 13 chromosomal islands, which are enriched for pseudogenes, transposons and other repetitive elements. At least 20% of A. fumigatus-specific genes appear to be functional and involved in carbohydrate and chitin catabolism, transport, detoxification, secondary metabolism and other functions that may facilitate the adaptation to heterogeneous environments such as soil or a mammalian host. Contrary to what was suggested previously, their origin cannot be attributed to horizontal gene transfer (HGT, but instead is likely to involve duplication, diversification and differential gene loss (DDL. The role of duplication in the origin of lineage-specific genes is further underlined by the discovery of genomic islands that seem to function as designated "gene dumps" and, perhaps, simultaneously, as "gene factories".

  10. Aspergillus and Penicillium in the Post-genomic Era

    DEFF Research Database (Denmark)

    Genome sequencing has affected studies into the biology of all classes of organisms and this is certainly true for filamentous fungi. The level with which biological systems can be studied since the availability of genomes and post-genomic technologies is beyond what most people could have imagined...... and a whole genus genome sequencing project in progress for Aspergillus. This book highlights some of the changes in the studies into these fungi, since the availability of genome sequences. The contributions vary from insights in the taxonomy of these genera, use of genomics for forward genetics and genomic...... in Penicillium and Aspergillus and a promise of many more things to come. An essential reference for everyone working with Aspergillus and Penicillium and other filamentous fungi and the book is also recommended reading for everyone with an interest in fungal genomics....

  11. Nitrogen Metabolism and Growth Enhancement in Tomato Plants Challenged with Trichoderma harzianum Expressing the Aspergillus nidulans Acetamidase amdS Gene.

    Science.gov (United States)

    Domínguez, Sara; Rubio, M Belén; Cardoza, Rosa E; Gutiérrez, Santiago; Nicolás, Carlos; Bettiol, Wagner; Hermosa, Rosa; Monte, Enrique

    2016-01-01

    Trichoderma is a fungal genus that includes species that are currently being used as biological control agents and/or as biofertilizers. In addition to the direct application of Trichoderma spp. as biocontrol agents in plant protection, recent studies have focused on the beneficial responses exerted on plants, stimulating the growth, activating the defenses, and/or improving nutrient uptake. The amdS gene, encoding an acetamidase of Aspergillus, has been used as a selectable marker for the transformation of filamentous fungi, including Trichoderma spp., but the physiological effects of the introduction of this gene into the genome of these microorganisms still remains unexplored. No evidence of amdS orthologous genes has been detected within the Trichoderma spp. genomes and the amdS heterologous expression in Trichoderma harzianum T34 did not affect the growth of this fungus in media lacking acetamide. However, it did confer the ability for the fungus to use this amide as a nitrogen source. Although a similar antagonistic behavior was observed for T34 and amdS transformants in dual cultures against Rhizoctonia solani, Botrytis cinerea, and Fusarium oxysporum, a significantly higher antifungal activity was detected in amdS transformants against F. oxysporum, compared to that of T34, in membrane assays on media lacking acetamide. In Trichoderma-tomato interaction assays, amdS transformants were able to promote plant growth to a greater extent than the wild-type T34, although compared with this strain the transformants showed similar capability to colonize tomato roots. Gene expression patterns from aerial parts of 3-week-old tomato plants treated with T34 and the amdS transformants have also been investigated using GeneChip Tomato Genome Arrays. The downregulation of defense genes and the upregulation of carbon and nitrogen metabolism genes observed in the microarrays were accompanied by (i) enhanced growth, (ii) increased carbon and nitrogen levels, and (iii) a

  12. Nitrogen Metabolism and Growth Enhancement in Tomato Plants Challenged with Trichoderma harzianum Expressing the Aspergillus nidulans Acetamidase amdS Gene

    Science.gov (United States)

    Domínguez, Sara; Rubio, M. Belén; Cardoza, Rosa E.; Gutiérrez, Santiago; Nicolás, Carlos; Bettiol, Wagner; Hermosa, Rosa; Monte, Enrique

    2016-01-01

    Trichoderma is a fungal genus that includes species that are currently being used as biological control agents and/or as biofertilizers. In addition to the direct application of Trichoderma spp. as biocontrol agents in plant protection, recent studies have focused on the beneficial responses exerted on plants, stimulating the growth, activating the defenses, and/or improving nutrient uptake. The amdS gene, encoding an acetamidase of Aspergillus, has been used as a selectable marker for the transformation of filamentous fungi, including Trichoderma spp., but the physiological effects of the introduction of this gene into the genome of these microorganisms still remains unexplored. No evidence of amdS orthologous genes has been detected within the Trichoderma spp. genomes and the amdS heterologous expression in Trichoderma harzianum T34 did not affect the growth of this fungus in media lacking acetamide. However, it did confer the ability for the fungus to use this amide as a nitrogen source. Although a similar antagonistic behavior was observed for T34 and amdS transformants in dual cultures against Rhizoctonia solani, Botrytis cinerea, and Fusarium oxysporum, a significantly higher antifungal activity was detected in amdS transformants against F. oxysporum, compared to that of T34, in membrane assays on media lacking acetamide. In Trichoderma-tomato interaction assays, amdS transformants were able to promote plant growth to a greater extent than the wild-type T34, although compared with this strain the transformants showed similar capability to colonize tomato roots. Gene expression patterns from aerial parts of 3-week-old tomato plants treated with T34 and the amdS transformants have also been investigated using GeneChip Tomato Genome Arrays. The downregulation of defense genes and the upregulation of carbon and nitrogen metabolism genes observed in the microarrays were accompanied by (i) enhanced growth, (ii) increased carbon and nitrogen levels, and (iii) a

  13. Approaches for Comparative Genomics in Aspergillus and Penicillium

    DEFF Research Database (Denmark)

    Rasmussen, Jane Lind Nybo; Theobald, Sebastian; Brandl, Julian;

    2016-01-01

    The number of available genomes in the closely related fungal genera Aspergillus and Penicillium is rapidly increasing. At the time of writing, the genomes of 62 species are available, and an even higher number is being prepared. Fungal comparative genomics is thus becoming steadily more powerful...

  14. The CreA repressor is the sole DNA-binding protein responsible for carbon catabolite repression of the alcA gene in Aspergillus nidulans via its binding to a couple of specific sites.

    Science.gov (United States)

    Panozzo, C; Cornillot, E; Felenbok, B

    1998-03-13

    Carbon catabolite repression is mediated in Aspergillus nidulans by the negative acting protein CreA. The CreA repressor plays a major role in the control of the expression of the alc regulon, encoding proteins required for the ethanol utilization pathway. It represses directly, at the transcriptional level, the specific transacting gene alcR, the two structural genes alcA and aldA, and other alc genes in all physiological growth conditions. Among the seven putative CreA sites identified in the alcA promoter region, we have determined the CreA functional targets in AlcR constitutive and derepressed genetic backgrounds. Two different divergent CreA sites, of which one overlaps a functional AlcR inverted repeat site, are largely responsible for alcA repression. Totally derepressed alcA expression is achieved when these two CreA sites are disrupted in addition to another single site, which overlaps the functional palindromic induction target. The fact that derepression is always associated with alcA overexpression is consistent with a competition model between AlcR and CreA for their cognate targets in the same region of the alcA promoter. Our results also indicate that the CreA repressor is necessary and sufficient for the total repression of the alcA gene.

  15. The zinc binuclear cluster activator AlcR is able to bind to single sites but requires multiple repeated sites for synergistic activation of the alcA gene in Aspergillus nidulans.

    Science.gov (United States)

    Panozzo, C; Capuano, V; Fillinger, S; Felenbok, B

    1997-09-01

    The alcA gene which is part of the recently identified ethanol regulon, is one of the most strongly inducible genes in Aspergillus nidulans. Its transcriptional activation is mediated by the AlcR transactivator which contains a DNA-binding domain belonging to the C6 zinc binuclear cluster family. AlcR differs from the other members of this family by several features, the most striking characteristic being its binding to both symmetric and asymmetric DNA sites with the same apparent affinity. However, AlcR is also able to bind to a single site with high affinity, suggesting that unlike the other C6 proteins, AlcR binds as a monomer. In this report, we show that AlcR targets, to be functional in vivo, have to be organized as inverted or direct repeats. In addition, we show a strong synergistic activation of alcA transcription in which the number and the position of the AlcR-binding sites are crucial. The fact that the AlcR unit for in vitro binding is a single site whereas the in vivo functional unit is a repeat opens the question of the mechanism of the strong alcA transactivation. These results show that AlcR displays both in vitro and in vivo a new range of binding specificity and provides a novel example in the C6 zinc cluster protein family.

  16. Uncovering transcriptional regulation of glycerol metabolism in Aspergilli through genome-wide gene expression data anlysis

    DEFF Research Database (Denmark)

    Salazar, Margarita Pena; Vongsangnak, Wanwipa; Panagiotou, Gianni;

    2009-01-01

    Glycerol is catabolized by a wide range of microorganisms including Aspergillus species. To identify the transcriptional regulation of glycerol metabolism in Aspergillus, we analyzed data from triplicate batch fermentations of three different Aspergilli (Aspergillus nidulans, Aspergillus oryzae...

  17. The population genomics of mycotoxin diversity in Aspergillus flavus and Aspergillus parasiticus

    Science.gov (United States)

    Mycotoxins, and especially the aflatoxins, are an enormous problem in agriculture, with aflatoxin B1 being the most carcinogenic known natural compound. The worldwide costs associated with aflatoxin monitoring and crop losses are in the hundreds of millions of dollars. Aspergillus flavus and A. par...

  18. Genome sequencing and analysis of the versatile cell factory Aspergillus niger CBS 513.88

    DEFF Research Database (Denmark)

    Pel, Herman J.; de Winde, Johannes H.; Archer, David B.;

    2007-01-01

    The filamentous fungus Aspergillus niger is widely exploited by the fermentation industry for the production of enzymes and organic acids, particularly citric acid. We sequenced the 33.9-megabase genome of A. niger CBS 513.88, the ancestor of currently used enzyme production strains. A high level...... clusters for fumonisin and ochratoxin A synthesis....

  19. Improved annotation through genome-scale metabolic modeling of Aspergillus oryzae

    DEFF Research Database (Denmark)

    Vongsangnak, Wanwipa; Olsen, Peter; Hansen, Kim;

    2008-01-01

    Background: Since ancient times the filamentous fungus Aspergillus oryzae has been used in the fermentation industry for the production of fermented sauces and the production of industrial enzymes. Recently, the genome sequence of A. oryzae with 12,074 annotated genes was released but the number...

  20. Draft Genome Sequences of Two Aspergillus fumigatus Strains, Isolated from the International Space Station.

    Science.gov (United States)

    Singh, Nitin Kumar; Blachowicz, Adriana; Checinska, Aleksandra; Wang, Clay; Venkateswaran, Kasthuri

    2016-07-14

    Draft genome sequences of Aspergillus fumigatus strains (ISSFT-021 and IF1SW-F4), opportunistic pathogens isolated from the International Space Station (ISS), were assembled to facilitate investigations of the nature of the virulence characteristics of the ISS strains to other clinical strains isolated on Earth.

  1. Draft genome sequence of an aflatoxigenic Aspergillus species, A. bombycis

    Science.gov (United States)

    The genome of the A. bombycis Type strain was sequenced using a Personal Genome Machine, followed by annotation of its predicted genes. The genome size for A. bombycis was found to be approximately 37 Mb and contained 12,266 genes. This announcement introduces a sequenced genome for an aflatoxigenic...

  2. Genome Sequences of Eight Aspergillus flavus spp. and One A. parasiticus sp., Isolated From Peanut Seeds in Georgia

    Science.gov (United States)

    Aspergillus flavus and A. parasiticus fungi, carcinogen-mycotoxins producers, infect peanut seeds, causing considerable impact on both human health and the economy. Here we report 9 genome sequences of Aspergillus spp. isolated from peanut seeds. The information obtained will allow conducting biodiv...

  3. Genome Sequences of Eight Aspergillus flavus spp. and One A. parasiticus sp., Isolated from Peanut Seeds in Georgia

    Science.gov (United States)

    Wang, Xinye Monica; Palencia, Edwin R.

    2016-01-01

    Aspergillus flavus and A. parasiticus fungi produce carcinogenic mycotoxins in peanut seeds, causing considerable impact on both human health and the economy. Here, we report nine genome sequences of Aspergillus spp., isolated from Georgia peanut seeds in 2014. The information obtained will lead to further biodiversity studies that are essential for developing control strategies. PMID:27081142

  4. Aspergillus mulundensis sp. nov., a new species for the fungus producing the antifungal echinocandin lipopeptides, mulundocandins.

    Science.gov (United States)

    Bills, Gerald F; Yue, Qun; Chen, Li; Li, Yan; An, Zhiqiang; Frisvad, Jens C

    2016-03-01

    The invalidly published name Aspergillus sydowii var. mulundensis was proposed for a strain of Aspergillus that produced new echinocandin metabolites designated as the mulundocadins. Reinvestigation of this strain (Y-30462=DSMZ 5745) using phylogenetic, morphological, and metabolic data indicated that it is a distinct and novel species of Aspergillus sect. Nidulantes. The taxonomic novelty, Aspergillus mulundensis, is introduced for this historically important echinocandin-producing strain. The closely related A. nidulans FGSC A4 has one of the most extensively characterized secondary metabolomes of any filamentous fungus. Comparison of the full-genome sequences of DSMZ 5745 and FGSC A4 indicated that the two strains share 33 secondary metabolite biosynthetic gene clusters. These shared gene clusters represent ~45% of the total secondary metabolome of each strain, thus indicating a high level intraspecific divergence in terms of secondary metabolism.

  5. Transient disruption of non-homologous end-joining facilitates targeted genome manipulations in the filamentous fungus Aspergillus nidulans

    DEFF Research Database (Denmark)

    Nielsen, Jakob Blæsbjerg; Nielsen, Michael Lynge; Mortensen, Uffe Hasbro

    2008-01-01

    ) activity is abolished and gene targeting can be performed with success rates identical to those obtained with permanent nkuA knock-out strains. When gene targeting is complete, the functional nkuA allele can be re-established via a simple selection step, thereby eliminating the risk that defective NHEJ...... be restored by sexual crossing. (c) 2007 Elsevier Inc. All rights reserved....

  6. Genome mining of the genetic diversity in the Aspergillus genus - from a collection of more than 30 Aspergillus species

    DEFF Research Database (Denmark)

    Rasmussen, Jane Lind Nybo; Vesth, Tammi Camilla; Theobald, Sebastian;

    , this project uses BLAST on the amino acid level to discover orthologs. With a potential of 300 Aspergillus species each having ~12,000 annotated genes, traditional clustering will demand supercomputing. Instead, our approach reduces the search space by identifying isoenzymes within each genome creating...

  7. Cryptic Sexuality in Aspergillus parasiticus and A. flavus

    Science.gov (United States)

    Ascomycetous fungi of the genus Aspergillus comprise a wide variety of species of biotechnological importance (e.g. A. sojae, A. oryzae, A. niger) as well as pathogens and toxin producers (e.g. A. flavus, A. parasiticus, A. fumigatus, A. nidulans). With the exception of A. nidulans, which is a homot...

  8. Signaling pathways for stress responses and adaptation in Aspergillus species: stress biology in the post-genomic era.

    Science.gov (United States)

    Hagiwara, Daisuke; Sakamoto, Kazutoshi; Abe, Keietsu; Gomi, Katsuya

    2016-09-01

    Aspergillus species are among the most important filamentous fungi in terms of industrial use and because of their pathogenic or toxin-producing features. The genomes of several Aspergillus species have become publicly available in this decade, and genomic analyses have contributed to an integrated understanding of fungal biology. Stress responses and adaptation mechanisms have been intensively investigated using the accessible genome infrastructure. Mitogen-activated protein kinase (MAPK) cascades have been highlighted as being fundamentally important in fungal adaptation to a wide range of stress conditions. Reverse genetics analyses have uncovered the roles of MAPK pathways in osmotic stress, cell wall stress, development, secondary metabolite production, and conidia stress resistance. This review summarizes the current knowledge on the stress biology of Aspergillus species, illuminating what we have learned from the genomic data in this "post-genomic era." PMID:27007956

  9. Recent advances in genome mining of secondary metabolites in Aspergillus terreus

    Directory of Open Access Journals (Sweden)

    Clay Chia Chun Wang

    2014-12-01

    Full Text Available Filamentous fungi are rich resources of secondary metabolites (SMs with a variety of interesting biological activities. Recent advances in genome sequencing and techniques in genetic manipulation have enabled researchers to study the biosynthetic genes of these SMs. Aspergillus terreus is the well-known producer of lovastatin, a cholesterol-lowering drug. This fungus also produces other SMs, including acetylaranotin, butyrolactones and territram, with interesting bioactivities. This review will cover recent progress in genome mining of SMs identified in this fungus. The identification and characterization of the gene cluster for these SMs, as well as the proposed biosynthetic pathways, will be discussed in depth.

  10. Draft Genome Sequences of Two Closely Related Aflatoxigenic Aspergillus Species Obtained from the Ivory Coast.

    Science.gov (United States)

    Moore, Geromy G; Mack, Brian M; Beltz, Shannon B

    2015-12-03

    Aspergillus ochraceoroseus and Aspergillus rambellii were isolated from soil detritus in Taï National Park, Ivory Coast, Africa. The Type strain for each species happens to be the only representative ever sampled. Both species secrete copious amounts of aflatoxin B1 and sterigmatocystin, because each of their genomes contains clustered genes for biosynthesis of these mycotoxins. We sequenced their genomes using a personal genome machine and found them to be smaller in size (A. ochraceoroseus = 23.9 Mb and A. rambellii = 26.1 Mb), as well as in numbers of predicted genes (7,837 and 7,807, respectively), compared to other sequenced Aspergilli. Our findings also showed that the A. ochraceoroseus Type strain contains a single MAT1-1 gene, while the Type strain of A. rambellii contains a single MAT1-2 gene, indicating that these species are heterothallic (self-infertile). These draft genomes will be useful for understanding the genes and pathways necessary for the cosynthesis of these two toxic secondary metabolites as well as the evolution of these pathways in aflatoxigenic fungi.

  11. Epidemiological and Genomic Landscape of Azole Resistance Mechanisms in Aspergillus Fungi

    Science.gov (United States)

    Hagiwara, Daisuke; Watanabe, Akira; Kamei, Katsuhiko; Goldman, Gustavo H.

    2016-01-01

    Invasive aspergillosis is a life-threatening mycosis caused by the pathogenic fungus Aspergillus. The predominant causal species is Aspergillus fumigatus, and azole drugs are the treatment of choice. Azole drugs approved for clinical use include itraconazole, voriconazole, posaconazole, and the recently added isavuconazole. However, epidemiological research has indicated that the prevalence of azole-resistant A. fumigatus isolates has increased significantly over the last decade. What is worse is that azole-resistant strains are likely to have emerged not only in response to long-term drug treatment but also because of exposure to azole fungicides in the environment. Resistance mechanisms include amino acid substitutions in the target Cyp51A protein, tandem repeat sequence insertions at the cyp51A promoter, and overexpression of the ABC transporter Cdr1B. Environmental azole-resistant strains harboring the association of a tandem repeat sequence and punctual mutation of the Cyp51A gene (TR34/L98H and TR46/Y121F/T289A) have become widely disseminated across the world within a short time period. The epidemiological data also suggests that the number of Aspergillus spp. other than A. fumigatus isolated has risen. Some non-fumigatus species intrinsically show low susceptibility to azole drugs, imposing the need for accurate identification, and drug susceptibility testing in most clinical cases. Currently, our knowledge of azole resistance mechanisms in non-fumigatus Aspergillus species such as A. flavus, A. niger, A. tubingensis, A. terreus, A. fischeri, A. lentulus, A. udagawae, and A. calidoustus is limited. In this review, we present recent advances in our understanding of azole resistance mechanisms particularly in A. fumigatus. We then provide an overview of the genome sequences of non-fumigatus species, focusing on the proteins related to azole resistance mechanisms. PMID:27708619

  12. Genomic Context of Azole Resistance Mutations in Aspergillus fumigatus Determined Using Whole-Genome Sequencing

    NARCIS (Netherlands)

    Abdolrasouli, A.; Rhodes, J.; Beale, M.A.; Hagen, F.; Rogers, T.R.; Chowdhary, A.; Meis, J.F.G.M.; Armstrong-James, D.; Fisher, M.C.

    2015-01-01

    A rapid and global emergence of azole resistance has been observed in the pathogenic fungus Aspergillus fumigatus over the past decade. The dominant resistance mechanism appears to be of environmental origin and involves mutations in the cyp51A gene, which encodes a protein targeted by triazole anti

  13. Whole genome evaluation of horizontal transfers in the pathogenic fungus Aspergillus fumigatus

    Directory of Open Access Journals (Sweden)

    Deschavanne Patrick

    2010-03-01

    Full Text Available Abstract Background Numerous cases of horizontal transfers (HTs have been described for eukaryote genomes, but in contrast to prokaryote genomes, no whole genome evaluation of HTs has been carried out. This is mainly due to a lack of parametric methods specially designed to take the intrinsic heterogeneity of eukaryote genomes into account. We applied a simple and tested method based on local variations of genomic signatures to analyze the genome of the pathogenic fungus Aspergillus fumigatus. Results We detected 189 atypical regions containing 214 genes, accounting for about 1 Mb of DNA sequences. However, the fraction of atypical DNA detected was smaller than the average amount detected in the same conditions in prokaryote genomes (3.1% vs 5.6%. It appeared that about one third of these regions contained no annotated genes, a proportion far greater than in prokaryote genomes. When analyzing the origin of these HTs by comparing their signatures to a home made database of species signatures, 3 groups of donor species emerged: bacteria (40%, fungi (25%, and viruses (22%. It is to be noticed that though inter-domain exchanges are confirmed, we only put in evidence very few exchanges between eukaryotic kingdoms. Conclusions In conclusion, we demonstrated that HTs are not negligible in eukaryote genomes, bearing in mind that in our stringent conditions this amount is a floor value, though of a lesser extent than in prokaryote genomes. The biological mechanisms underlying those transfers remain to be elucidated as well as the biological functions of the transferred genes.

  14. Exploiting proteomic data for genome annotation and gene model validation in Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Grigoriev Igor V

    2009-02-01

    Full Text Available Abstract Background Proteomic data is a potentially rich, but arguably unexploited, data source for genome annotation. Peptide identifications from tandem mass spectrometry provide prima facie evidence for gene predictions and can discriminate over a set of candidate gene models. Here we apply this to the recently sequenced Aspergillus niger fungal genome from the Joint Genome Institutes (JGI and another predicted protein set from another A.niger sequence. Tandem mass spectra (MS/MS were acquired from 1d gel electrophoresis bands and searched against all available gene models using Average Peptide Scoring (APS and reverse database searching to produce confident identifications at an acceptable false discovery rate (FDR. Results 405 identified peptide sequences were mapped to 214 different A.niger genomic loci to which 4093 predicted gene models clustered, 2872 of which contained the mapped peptides. Interestingly, 13 (6% of these loci either had no preferred predicted gene model or the genome annotators' chosen "best" model for that genomic locus was not found to be the most parsimonious match to the identified peptides. The peptides identified also boosted confidence in predicted gene structures spanning 54 introns from different gene models. Conclusion This work highlights the potential of integrating experimental proteomics data into genomic annotation pipelines much as expressed sequence tag (EST data has been. A comparison of the published genome from another strain of A.niger sequenced by DSM showed that a number of the gene models or proteins with proteomics evidence did not occur in both genomes, further highlighting the utility of the method.

  15. Complete Genome Sequence of the Filamentous Fungus Aspergillus westerdijkiae Reveals the Putative Biosynthetic Gene Cluster of Ochratoxin A.

    Science.gov (United States)

    Chakrabortti, Alolika; Li, Jinming; Liang, Zhao-Xun

    2016-01-01

    Ochratoxin A (OTA) is a common mycotoxin that contaminates food and agricultural products. Sequencing of the complete genome of Aspergillus westerdijkiae, a major producer of OTA, reveals more than 50 biosynthetic gene clusters, including a putative OTA biosynthetic gene cluster that encodes a dozen of enzymes, transporters, and regulatory proteins. PMID:27635003

  16. Complete Genome Sequence of the Filamentous Fungus Aspergillus westerdijkiae Reveals the Putative Biosynthetic Gene Cluster of Ochratoxin A

    Science.gov (United States)

    Chakrabortti, Alolika; Li, Jinming

    2016-01-01

    Ochratoxin A (OTA) is a common mycotoxin that contaminates food and agricultural products. Sequencing of the complete genome of Aspergillus westerdijkiae, a major producer of OTA, reveals more than 50 biosynthetic gene clusters, including a putative OTA biosynthetic gene cluster that encodes a dozen of enzymes, transporters, and regulatory proteins. PMID:27635003

  17. Aspergillus flavus genomics: gateway to human and animal health, food safety, and crop resistance to diseases.

    Science.gov (United States)

    Yu, Jiujiang; Cleveland, Thomas E; Nierman, William C; Bennett, Joan W

    2005-12-01

    Aspergillus flavus is an imperfect filamentous fungus that is an opportunistic pathogen causing invasive and non-invasive aspergillosis in humans, animals, and insects. It also causes allergic reactions in humans. A. flavus infects agricultural crops and stored grains and produces the most toxic and potent carcinogic metabolites such as aflatoxins and other mycotoxins. Breakthroughs in A. flavus genomics may lead to improvement in human health, food safety, and agricultural economy. The availability of A. flavus genomic data marks a new era in research for fungal biology, medical mycology, agricultural ecology, pathogenicity, mycotoxin biosynthesis, and evolution. The availability of whole genome microarrays has equipped scientists with a new powerful tool for studying gene expression under specific conditions. They can be used to identify genes responsible for mycotoxin biosynthesis and for fungal infection in humans, animals and plants. A. flavus genomics is expected to advance the development of therapeutic drugs and to provide information for devising strategies in controlling diseases of humans and other animals. Further, it will provide vital clues for engineering commercial crops resistant to fungal infection by incorporating antifungal genes that may prevent aflatoxin contamination of agricultural harvest. PMID:16499411

  18. Physiological characterisation of acuB deletion in Aspergillus niger

    DEFF Research Database (Denmark)

    Meijer, Susan Lisette; De Jongh, Willem Adriaan; Olsson, Lisbeth;

    2009-01-01

    The acuB gene of Aspergillus niger is an ortholog of facB in Aspergillus nidulans. Under carbon-repression conditions, facB is repressed, thereby preventing acetate metabolism when the repressing carbon source is present. Even though facB is reported to be repressed directly by CreA, it is believed...

  19. Development of RFLP-PCR method for the identification of medically important Aspergillus species using single restriction enzyme MwoI

    Directory of Open Access Journals (Sweden)

    K. Diba

    2014-06-01

    Full Text Available In this study we attempted to modify the PCR-RFLP method using restriction enzyme MwoI for the identification of medically important Aspergillus species. Our subjects included nine standard Aspergillus species and 205 Aspergillus isolates of approved hospital acquired infections and hospital indoor sources. First of all, Aspergillus isolates were identified in the level of species by using morphologic method. A twenty four hours culture was performed for each isolates to harvest Aspergillus mycelia and then genomic DNA was extracted using Phenol-Chloroform method. PCR-RFLP using single restriction enzyme MwoI was performed in ITS regions of rDNA gene. The electrophoresis data were analyzed and compared with those of morphologic identifications. Total of 205 Aspergillus isolates included 153 (75% environmental and 52 (25% clinical isolates. A. flavus was the most frequently isolate in our study (55%, followed by A. niger 65(31.7%, A. fumigatus 18(8.7%, A. nidulans and A. parasiticus 2(1% each. MwoI enabled us to discriminate eight medically important Aspergillus species including A. fumigatus, A. niger, A. flavus as the most common isolated species. PCR-RFLP method using the restriction enzyme MwoI is a rapid and reliable test for identification of at least the most medically important Aspergillus species.

  20. Development of RFLP-PCR method for the identification of medically important Aspergillus species using single restriction enzyme MwoI.

    Science.gov (United States)

    Diba, K; Mirhendi, H; Kordbacheh, P; Rezaie, S

    2014-01-01

    In this study we attempted to modify the PCR-RFLP method using restriction enzyme MwoI for the identification of medically important Aspergillus species. Our subjects included nine standard Aspergillus species and 205 Aspergillus isolates of approved hospital acquired infections and hospital indoor sources. First of all, Aspergillus isolates were identified in the level of species by using morphologic method. A twenty four hours culture was performed for each isolates to harvest Aspergillus mycelia and then genomic DNA was extracted using Phenol-Chloroform method. PCR-RFLP using single restriction enzyme MwoI was performed in ITS regions of rDNA gene. The electrophoresis data were analyzed and compared with those of morphologic identifications. Total of 205 Aspergillus isolates included 153 (75%) environmental and 52 (25%) clinical isolates. A. flavus was the most frequently isolate in our study (55%), followed by A. niger 65(31.7%), A. fumigatus 18(8.7%), A. nidulans and A. parasiticus 2(1% each). MwoI enabled us to discriminate eight medically important Aspergillus species including A. fumigatus, A. niger, A. flavus as the most common isolated species. PCR-RFLP method using the restriction enzyme MwoI is a rapid and reliable test for identification of at least the most medically important Aspergillus species.

  1. Genome shuffling of Aspergillus glaucus HGZ-2 for enhanced cellulase production.

    Science.gov (United States)

    Zhao, Yuping; Jiang, Changxing; Yu, Hupeng; Fang, Fang; Yang, Jingzhu

    2014-10-01

    The production of cellulase from Aspergillus glaucus HGZ-2 was improved by using genome shuffling. The starting populations, obtained by UV irradiation, were subjected to recursive protoplast fusion. The optimal conditions for protoplast formation and regeneration were 7 mg/ml snailase and 5 mg/ml cellulase at 34 °C for 3.0 h using 0.7 M NaCl as an osmotic stabilizer. The protoplasts were inactivated under UV for 30 min or heated at 50 °C for 50 min, and a fusant probability of about 100 % was observed. The positive colonies were created by fusing the inactivated protoplasts. The optimal conditions for protoplast fusion were PEG6000 concentration of 35 %, CaCl2 concentration of 0.02 M, and incubation time of 12 min. After two rounds of genome shuffling, one strain (Y) was obtained. Its filter paper cellulase (FPase) and carboxymethyl cellulase (CMCase) activity reached 71 and 70 U/ml, respectively, which were increased by 1.95-fold and 1.72-fold in comparison with that of its ancestor strain. The results indicated that genome shuffling was an efficient means for the improved production of cellulases by A. glaucus HGZ-2. PMID:25099375

  2. Aflatoxin B1-producing Aspergillus in sun-dried medicinal plant materials

    OpenAIRE

    Chinaputi, A.; Lim, S; Petcharat, V.; Chuenchit, S.; Pathanadech, A.

    2001-01-01

    Fifty sun-dried medicinal plants were obtained from fraditional drug stores in Songkhla Province, Thailand, and examined for Aspergillus and aflatoxin B1. 288 isolates of Aspergillus were obtaines by standard blotter plate and 25 species were identified. The most common species were A. niger with 99 isolates, A. Flavus 84 isolates, A. terreus 33 isolates, A. oryzae 25 isolates, A.nidulans (Emericella nidulans) 10 isolates, A fumigatus 9 isolates and A. chevalieri (Eurotium chevalieri) 8 isola...

  3. Genomic sequence of the pathogenic and allergenic filamentous fungus Aspergillus fumigatus.

    Science.gov (United States)

    Nierman, William C; Pain, Arnab; Anderson, Michael J; Wortman, Jennifer R; Kim, H Stanley; Arroyo, Javier; Berriman, Matthew; Abe, Keietsu; Archer, David B; Bermejo, Clara; Bennett, Joan; Bowyer, Paul; Chen, Dan; Collins, Matthew; Coulsen, Richard; Davies, Robert; Dyer, Paul S; Farman, Mark; Fedorova, Nadia; Fedorova, Natalie; Feldblyum, Tamara V; Fischer, Reinhard; Fosker, Nigel; Fraser, Audrey; García, Jose L; García, Maria J; Goble, Arlette; Goldman, Gustavo H; Gomi, Katsuya; Griffith-Jones, Sam; Gwilliam, Ryan; Haas, Brian; Haas, Hubertus; Harris, David; Horiuchi, H; Huang, Jiaqi; Humphray, Sean; Jiménez, Javier; Keller, Nancy; Khouri, Hoda; Kitamoto, Katsuhiko; Kobayashi, Tetsuo; Konzack, Sven; Kulkarni, Resham; Kumagai, Toshitaka; Lafon, Anne; Lafton, Anne; Latgé, Jean-Paul; Li, Weixi; Lord, Angela; Lu, Charles; Majoros, William H; May, Gregory S; Miller, Bruce L; Mohamoud, Yasmin; Molina, Maria; Monod, Michel; Mouyna, Isabelle; Mulligan, Stephanie; Murphy, Lee; O'Neil, Susan; Paulsen, Ian; Peñalva, Miguel A; Pertea, Mihaela; Price, Claire; Pritchard, Bethan L; Quail, Michael A; Rabbinowitsch, Ester; Rawlins, Neil; Rajandream, Marie-Adele; Reichard, Utz; Renauld, Hubert; Robson, Geoffrey D; Rodriguez de Córdoba, Santiago; Rodríguez-Peña, Jose M; Ronning, Catherine M; Rutter, Simon; Salzberg, Steven L; Sanchez, Miguel; Sánchez-Ferrero, Juan C; Saunders, David; Seeger, Kathy; Squares, Rob; Squares, Steven; Takeuchi, Michio; Tekaia, Fredj; Turner, Geoffrey; Vazquez de Aldana, Carlos R; Weidman, Janice; White, Owen; Woodward, John; Yu, Jae-Hyuk; Fraser, Claire; Galagan, James E; Asai, Kiyoshi; Machida, Masayuki; Hall, Neil; Barrell, Bart; Denning, David W

    2005-12-22

    Aspergillus fumigatus is exceptional among microorganisms in being both a primary and opportunistic pathogen as well as a major allergen. Its conidia production is prolific, and so human respiratory tract exposure is almost constant. A. fumigatus is isolated from human habitats and vegetable compost heaps. In immunocompromised individuals, the incidence of invasive infection can be as high as 50% and the mortality rate is often about 50% (ref. 2). The interaction of A. fumigatus and other airborne fungi with the immune system is increasingly linked to severe asthma and sinusitis. Although the burden of invasive disease caused by A. fumigatus is substantial, the basic biology of the organism is mostly obscure. Here we show the complete 29.4-megabase genome sequence of the clinical isolate Af293, which consists of eight chromosomes containing 9,926 predicted genes. Microarray analysis revealed temperature-dependent expression of distinct sets of genes, as well as 700 A. fumigatus genes not present or significantly diverged in the closely related sexual species Neosartorya fischeri, many of which may have roles in the pathogenicity phenotype. The Af293 genome sequence provides an unparalleled resource for the future understanding of this remarkable fungus. PMID:16372009

  4. The evolutionary imprint of domestication on genome variation and function of the filamentous fungus Aspergillus oryzae.

    Science.gov (United States)

    Gibbons, John G; Salichos, Leonidas; Slot, Jason C; Rinker, David C; McGary, Kriston L; King, Jonas G; Klich, Maren A; Tabb, David L; McDonald, W Hayes; Rokas, Antonis

    2012-08-01

    The domestication of animals, plants, and microbes fundamentally transformed the lifestyle and demography of the human species [1]. Although the genetic and functional underpinnings of animal and plant domestication are well understood, little is known about microbe domestication [2-6]. Here, we systematically examined genome-wide sequence and functional variation between the domesticated fungus Aspergillus oryzae, whose saccharification abilities humans have harnessed for thousands of years to produce sake, soy sauce, and miso from starch-rich grains, and its wild relative A. flavus, a potentially toxigenic plant and animal pathogen [7]. We discovered dramatic changes in the sequence variation and abundance profiles of genes and wholesale primary and secondary metabolic pathways between domesticated and wild relative isolates during growth on rice. Our data suggest that, through selection by humans, an atoxigenic lineage of A. flavus gradually evolved into a "cell factory" for enzymes and metabolites involved in the saccharification process. These results suggest that whereas animal and plant domestication was largely driven by Neolithic "genetic tinkering" of developmental pathways, microbe domestication was driven by extensive remodeling of metabolism.

  5. Functional Genomic Analysis of Aspergillus flavus Interacting with Resistant and Susceptible Peanut

    Science.gov (United States)

    Wang, Houmiao; Lei, Yong; Yan, Liying; Wan, Liyun; Ren, Xiaoping; Chen, Silong; Dai, Xiaofeng; Guo, Wei; Jiang, Huifang; Liao, Boshou

    2016-01-01

    In the Aspergillus flavus (A. flavus)–peanut pathosystem, development and metabolism of the fungus directly influence aflatoxin contamination. To comprehensively understand the molecular mechanism of A. flavus interaction with peanut, RNA-seq was used for global transcriptome profiling of A. flavus during interaction with resistant and susceptible peanut genotypes. In total, 67.46 Gb of high-quality bases were generated for A. flavus-resistant (af_R) and -susceptible peanut (af_S) at one (T1), three (T2) and seven (T3) days post-inoculation. The uniquely mapped reads to A. flavus reference genome in the libraries of af_R and af_S at T2 and T3 were subjected to further analysis, with more than 72% of all obtained genes expressed in the eight libraries. Comparison of expression levels both af_R vs. af_S and T2 vs. T3 uncovered 1926 differentially expressed genes (DEGs). DEGs associated with mycelial growth, conidial development and aflatoxin biosynthesis were up-regulated in af_S compared with af_R, implying that A. flavus mycelia more easily penetrate and produce much more aflatoxin in susceptible than in resistant peanut. Our results serve as a foundation for understanding the molecular mechanisms of aflatoxin production differences between A. flavus-R and -S peanut, and offer new clues to manage aflatoxin contamination in crops. PMID:26891328

  6. Functional Genomic Analysis of Aspergillus flavus Interacting with Resistant and Susceptible Peanut

    Directory of Open Access Journals (Sweden)

    Houmiao Wang

    2016-02-01

    Full Text Available In the Aspergillus flavus (A. flavus–peanut pathosystem, development and metabolism of the fungus directly influence aflatoxin contamination. To comprehensively understand the molecular mechanism of A. flavus interaction with peanut, RNA-seq was used for global transcriptome profiling of A. flavus during interaction with resistant and susceptible peanut genotypes. In total, 67.46 Gb of high-quality bases were generated for A. flavus-resistant (af_R and -susceptible peanut (af_S at one (T1, three (T2 and seven (T3 days post-inoculation. The uniquely mapped reads to A. flavus reference genome in the libraries of af_R and af_S at T2 and T3 were subjected to further analysis, with more than 72% of all obtained genes expressed in the eight libraries. Comparison of expression levels both af_R vs. af_S and T2 vs. T3 uncovered 1926 differentially expressed genes (DEGs. DEGs associated with mycelial growth, conidial development and aflatoxin biosynthesis were up-regulated in af_S compared with af_R, implying that A. flavus mycelia more easily penetrate and produce much more aflatoxin in susceptible than in resistant peanut. Our results serve as a foundation for understanding the molecular mechanisms of aflatoxin production differences between A. flavus-R and -S peanut, and offer new clues to manage aflatoxin contamination in crops.

  7. rmtA, encoding a putative anginine methyltransferase, regulates secondary metabolism and development in Aspergillus flavus

    Science.gov (United States)

    Aspergillus flavus is found colonizing numerous oil seed crops such as corn, peanuts, sorghum, treenuts and cotton worldwide, contaminating them with aflatoxin and other harmful potent toxins. In the phylogenetically related model fungus Aspergillus nidulans, the methyltransferase, RmtA, has been de...

  8. Comparative genomics of citric-acid-producing Aspergillus niger ATCC 1015 versus enzyme-producing CBS 513.88

    DEFF Research Database (Denmark)

    Andersen, Mikael Rørdam; Salazar, Margarita Pena; Schaap, Peter J.;

    2011-01-01

    The filamentous fungus Aspergillus niger exhibits great diversity in its phenotype. It is found globally, both as marine and terrestrial strains, produces both organic acids and hydrolytic enzymes in high amounts, and some isolates exhibit pathogenicity. Although the genome of an industrial enzyme...... and phylogenetics. Detailed lists of alleles were generated, and genotypic differences were observed to accumulate in metabolic pathways essential to acid production and protein synthesis. A transcriptome analysis supported up-regulation of genes associated with biosynthesis of amino acids that are abundant...

  9. Heterologous Transformation and Expression of Hericium erinaceum Manganese Peroxidase 1 Gene in Aspergillus nidulans%猴头菌锰过氧化物酶1基因在构巢曲霉的异源转化与表达

    Institute of Scientific and Technical Information of China (English)

    尹立伟; 池玉杰

    2013-01-01

    The recombinant plasmid pLB01/He-mnp1 which contains a gene encoding for manganese peroxidase (He-mnp1) from Hericium erinaceum CB1 was transformated into protoplasts of auxotrophic stain TN02A7 of Aspergillus nidulans by means of protoplast transformation method mediated by PEG/CaC12so as to enhance MnP production.A transformant stain TN02A7-He-mnp1 of A.nidulans was gained,the gene He-mnp1 was expressed under the control of alcohol dehydrogenase alcA (p) promoter.The transformant stain TN02A7-He-mnp1,auxotrophic stain TN02A7,wild stain of A.nidulans WJA01,and H.erinaceum CB1 were cultured under the same lignin condition and detected the MnP activity.The results showed that TN02A7-He-mnp1 could produce MnP activity in the absence and presence of heme,but the MnP activity was up to 38.31 U · L-1 on 96h with 0.05 g · L-1 heme which was 8.64 times higher than that without heme but less than that of H.erinaceum CB1,whereas TN02A7 and WJA01 could not produce MnP activity at any time,indicating that the gene He-mnp1 had been successfully transformed into TN02A7-He-mnp1 and expressed in lignin environment,and the heme was one of the restrictive factors for rescombinant mnp gene to express in A.nidulans.The study provides a new method to produce MnP and enhance MnP yield.%为提高猴头菌菌株CB1锰过氧化物酶(MnP)基因的表达产量,采用PEG/CaCl2介导的原生质体转化方法,将携带有He-mnp1的重组质粒pLB01/He-mnp1转入到构巢曲霉尿嘧啶尿苷营养缺陷菌株TN02A7的原生质体中,获得了转化子菌株TN02A 7-He-mnp1,并在乙醇脱氢酶启动子alcA(P)控制下实现了异源表达.将TN02A7-He-mnp1、TN02A7、构巢曲霉野生型菌株WJA01、猴头菌菌株CB1在相同的木质素环境下进行培养并检测MnP酶活性,结果表明:转化子菌株TN02A7-He-mnp1在0.05 g· L-1血红素的情况下、诱导96 h后酶活性最高为38.31 U·L-1,比不添加血红素的酶活力高8.64倍,但比猴头菌菌株CB1

  10. Aspergillus flavus Genomic Data Mining Provides Clues for Its Use in Producing Biobased Products

    Science.gov (United States)

    Aspergillus flavus is notorious for its ability to produce aflatoxins. It is also an opportunistic pathogen that infects plants, animals and human beings. The ability to survive in the natural environment, living on plant tissues (leaves or stalks), live or dead insects make A. flavus a ubiquitous...

  11. Genome-scale analysis of the high-efficient protein secretion system of Aspergillus oryzae

    DEFF Research Database (Denmark)

    Liu, Lifang; Feizi, Amir; Osterlund, Tobias;

    2014-01-01

    Background: The koji mold, Aspergillus oryzae is widely used for the production of industrial enzymes due to its particularly high protein secretion capacity and ability to perform post-translational modifications. However, systemic analysis of its secretion system is lacking, generally due to th...

  12. Genome wide association mapping of Aspergillus flavus and aflatoxin accumulation resistance in maize

    Science.gov (United States)

    Contamination of maize with aflatoxin, produced by the fungus Aspergillus flavus, has severe health and economic consequences. Efforts to reduce aflatoxin accumulation in maize have focused on identifying and selecting germplasm with natural host resistance factors, and several maize lines with sign...

  13. Identification and characterization of starch and inulin modifying network of Aspergillus niger by functional genomics

    NARCIS (Netherlands)

    Yuan, Xiao-Lian

    2008-01-01

    Aspergillus niger produces a wide variety of carbohydrate hydrolytic enzymes which have potential applications in the baking, starch, textile, food and feed industries. The goal of this thesis is to unravel the molecular mechanisms of starch and inulin modifying network of A. niger, in order to impr

  14. Aspergillus flavus whole genome and EST sequence releases and construction of homologous gene search blast server

    Science.gov (United States)

    Aflatoxins are toxic and carcinogenic secondary metabolites. These compounds, produced by Aspergillus flavus and A. parasiticus, contaminate pre-harvest agricultural crops in the field and post-harvest grains during storage. In order to reduce and eliminate aflatoxin contamination of food and feed...

  15. Draft genome sequences of two closely-related aflatoxigenic Aspergillus species obtained from the Ivory Coast

    Science.gov (United States)

    The genomes of the A. ochraceoroseus and A. rambellii type strains were sequenced using a personal genome machine, followed by annotation of their genes. The genome size for A. ochraceoroseus was found to be approximately 23 Mb and contained 7,837 genes, while the A. rambellii genome was found to be...

  16. Suppression of Aspergillus by Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Jensen, Britt Guillaume; Jelsbak, Lars; Søndergaard, Ib;

    Objectives: Cystic fibrosis patients are commonly infected by Pseudomonas aeruginosa, but Aspergilli are also frequently isolated. Our aim was to examine the possible interaction between P. aeruginosa and different Aspergillus. Methods: A suspension of 106 fungal spores/ml was streaked onto WATM...... suppressed growth of A. fumigatus, A. niger, A. flavus, A. oryzae, A. terreus and E. nidulans. HPLC and LC-DAD-MS results showed an increase in phenazine-1-carboxylic acid and phenazine-1-carboxamide production by P. aeruginosa in the contact area of Aspergillus. Different quinolones were also identified...

  17. The role of thiol species in the hypertolerance of Aspergillus sp. P37 to arsenic.

    Science.gov (United States)

    Cánovas, David; Vooijs, Riet; Schat, Henk; de Lorenzo, Víctor

    2004-12-01

    Aspergillus sp. P37 is an arsenate-hypertolerant fungus isolated from a river in Spain with a long history of contamination with metals. This strain is able to grow in the presence of 0.2 M arsenate, i.e. 20-fold higher than the reference strain, Aspergillus nidulans TS1. Although Aspergillus sp. P37 reduces As(V) to As(III), which is slowly pumped out of the cell, the measured efflux of oxyanions is insufficient to explain the high tolerance levels of this strain. To gain an insight into this paradox, the accumulation of acid-soluble thiol species in Aspergillus sp. P37 when exposed to arsenic was compared with that of the arsenic-sensitive A. nidulans TS1 strain. Increasing levels of arsenic in the medium did not diminish the intracellular pool of reduced glutathione in Aspergillus sp. P37, in sharp contrast with the decline of glutathione in A. nidulans under the same conditions. Furthermore, concentrations of arsenic that were inhibitory for the sensitive A. nidulans strain (e.g. 50 mM and above) provoked a massive formation of vacuoles filled with thiol species. Because the major fraction of the cellular arsenic was present as the glutathione conjugate As(GS)3, it is plausible that the arsenic-hypertolerant phenotype of Aspergillus sp. P37 is in part due to an enhanced capacity to maintain a large intracellular glutathione pool under conditions of arsenic exposure and to sequester As(GS)3 in vacuoles. High pressure liquid chromatography analysis of cell extracts revealed that the contact of Aspergillus sp. P37 (but not A. nidulans) with high arsenic concentrations (> or =150 mM) induced the production of small quantities of a distinct thiol species indistinguishable from plant phytochelatin-2. Yet, we argue that phytochelatins do not explain arsenic resistance in Aspergillus, and we advocate the role of As(GS)3 complexes in arsenic detoxification.

  18. GDP-mannose pyrophosphorylase is essential for cell wall integrity, morphogenesis and viability of Aspergillus fumigatus.

    Science.gov (United States)

    Jiang, Hechun; Ouyang, Haomiao; Zhou, Hui; Jin, Cheng

    2008-09-01

    GDP-mannose pyrophosphorylase (GMPP) catalyses the synthesis of GDP-mannose, which is the precursor for the mannose residues in glycoconjugates, using mannose 1-phosphate and GTP as substrates. Repression of GMPP in yeast leads to phenotypes including cell lysis, defective cell wall, and failure of polarized growth and cell separation. Although several GMPPs have been isolated and characterized in filamentous fungi, the physiological consequences of their actions are not clear. In this study, Afsrb1, which is a homologue of yeast SRB1/PSA1/VIG9, was identified in the Aspergillus fumigatus genome. The Afsrb1 gene was expressed in Escherichia coli, and recombinant AfSrb1 was functionally confirmed as a GMPP. By the replacement of the native Afsrb1 promoter with an inducible Aspergillus nidulans alcA promoter, the conditional inactivation mutant strain YJ-gmpp was constructed. The presence of 3 % glucose completely blocked transcription of P(alcA)-Afsrb1, and was lethal to strain YJ-gmpp. Repression of Afsrb1 expression in strain YJ-gmpp led to phenotypes including hyphal lysis, defective cell wall, impaired polarity maintenance, and branching site selection. Also, rapid germination and reduced conidiation were documented. However, in contrast to yeast, strain YJ-gmpp retained the ability to direct polarity establishment and septation. Our results showed that the Afsrb1 gene is essential for cell wall integrity, morphogenesis and viability of Aspergillus fumigatus.

  19. Metabolic control analysis of xylose catabolism in Aspergillus

    DEFF Research Database (Denmark)

    Prathumpai, Wai; Gabelgaard, J.B.; Wanchanthuek, P.;

    2003-01-01

    A kinetic model for xylose catabolism in Aspergillus is proposed. From a thermodynamic analysis it was found that the intermediate xylitol will accumulate during xylose catabolism. Use of the kinetic model allowed metabolic control analysis (MCA) of the xylose catabolic pathway to be carried out...... nidulans grown on media containing xylose, and a concentration up to 30 mM was found. Applying MCA showed that the first polyol dehydrogenase (XDH) in the catabolic pathway of xylose exerted the main flux control in the two strains of A. nidulans and A. niger NW324, but the flux control was exerted mainly...

  20. Expression and characterization of an endo-1,4-β-galactanase from Emericella nidulans in Pichia pastoris for enzymatic design of potentially prebiotic oligosaccharides from potato galactans

    DEFF Research Database (Denmark)

    Michalak, Malwina; Thomassen, Lise Vestergaard; Roytio, Henna;

    2012-01-01

    Aspergillus niger used as benchmark. The E. nidulans enzyme expressed in P. pastoris generated a spectrum poly- and oligo-saccharides which were fractionated by membrane filtration. The potential growth promoting properties of each fraction were evaluated by growth of beneficial gut microbes and pathogenic...... strain. The enzyme was purified by Cu2+ affinity chromatography and its optimal reaction conditions were determined to pH 5 and 49°C via a statistical experimental design. The specific activity of the E. nidulans enzyme expressed in P. pastoris was similar to that of an endo-1,4-β-galactanase from...

  1. PCR-RFLP on β-tubulin gene for rapid identification of the most clinically important species of Aspergillus.

    Science.gov (United States)

    Nasri, Tuba; Hedayati, Mohammad Taghi; Abastabar, Mahdi; Pasqualotto, Alessandro C; Armaki, Mojtaba Taghizadeh; Hoseinnejad, Akbar; Nabili, Mojtaba

    2015-10-01

    Aspergillus species are important agents of life-threatening infections in immunosuppressed patients. Proper speciation in the Aspergilli has been justified based on varied fungal virulence, clinical presentations, and antifungal resistance. Accurate identification of Aspergillus species usually relies on fungal DNA sequencing but this requires expensive equipment that is not available in most clinical laboratories. We developed and validated a discriminative low-cost PCR-based test to discriminate Aspergillus isolates at the species level. The Beta tubulin gene of various reference strains of Aspergillus species was amplified using the universal fungal primers Bt2a and Bt2b. The PCR products were subjected to digestion with a single restriction enzyme AlwI. All Aspergillus isolates were subjected to DNA sequencing for final species characterization. The PCR-RFLP test generated unique patterns for six clinically important Aspergillus species, including Aspergillus flavus, Aspergillus fumigatus, Aspergillus nidulans, Aspergillus terreus, Aspergillus clavatus and Aspergillus nidulans. The one-enzyme PCR-RFLP on Beta tubulin gene designed in this study is a low-cost tool for the reliable and rapid differentiation of the clinically important Aspergillus species.

  2. Biosynthetic Pathway for the Epipolythiodioxopiperazine Acetylaranotin in Aspergillus terreus Revealed by Genome-based Deletion Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Chun-Jun; Yeh, Hsu-Hua; Chiang, Yi Ming; Sanchez, James F.; Chang, ShuLin; Bruno, Kenneth S.; Wang, Clay C.

    2013-04-15

    Abstract Epipolythiodioxopiperazines (ETPs) are a class of fungal secondary metabolites derived from cyclic peptides. Acetylaranotin belongs to one structural subgroup of ETPs characterized by the presence of a seven-membered dihydrooxepine ring. Defining the genes involved in acetylaranotin biosynthesis should provide a means to increase production of these compounds and facilitate the engineering of second-generation molecules. The filamentous fungus Aspergillus terreus produces acetylaranotin and related natural products. Using targeted gene deletions, we have identified a cluster of 9 genes including one nonribosomal peptide synthase gene, ataP, that is required for acetylaranotin biosynthesis. Chemical analysis of the wild type and mutant strains enabled us to isolate seventeen natural products that are either intermediates in the normal biosynthetic pathway or shunt products that are produced when the pathway is interrupted through mutation. Nine of the compounds identified in this study are novel natural products. Our data allow us to propose a complete biosynthetic pathway for acetylaranotin and related natural products.

  3. Genome-based Characterization of Two Prenylation Steps in the Assembly of the Stephacidin and Notoamide Anticancer Agents in a Marine-derived Aspergillus sp

    OpenAIRE

    Ding, Yousong; de Wet, Jeffrey R.; Cavalcoli, James; Li, Shengying; Greshock, Thomas J.; Miller, Kenneth A.; Finefield, Jennifer M.; Sunderhaus, James D.; McAfoos, Timothy; Tsukamoto, Sachiko; Williams, Robert M.; Sherman, David H.

    2010-01-01

    Stephacidin and notoamide natural products belong to a group of prenylated indole alkaloids containing a core bicyclo[2.2.2]diazaoctane ring system. These bioactive fungal secondary metabolites have a range of unusual structural and stereochemical features but their biosynthesis has remained uncharacterized. Herein, we report the first biosynthetic gene cluster for this class of fungal alkaloids based on whole genome sequencing of a marine-derived Aspergillus sp. Two central pathway enzymes c...

  4. Negative regulation and developmental competence in Aspergillus.

    Science.gov (United States)

    Lee, Mi-Kyung; Kwon, Nak-Jung; Lee, Im-Soon; Jung, Seunho; Kim, Sun-Chang; Yu, Jae-Hyuk

    2016-01-01

    Asexual development (conidiation) in the filamentous fungus Aspergillus nidulans is governed by orchestrated gene expression. The three key negative regulators of conidiation SfgA, VosA, and NsdD act at different control point in the developmental genetic cascade. Here, we have revealed that NsdD is a key repressor affecting the quantity of asexual spores in Aspergillus. Moreover, nullifying both nsdD and vosA results in abundant formation of the development specific structure conidiophores even at 12 h of liquid culture, and near constitutive activation of conidiation, indicating that acquisition of developmental competence involves the removal of negative regulation exerted by both NsdD and VosA. NsdD's role in repressing conidiation is conserved in other aspergilli, as deleting nsdD causes enhanced and precocious activation of conidiation in Aspergillus fumigatus or Aspergillus flavus. In vivo NsdD-DNA interaction analyses identify three NsdD binding regions in the promoter of the essential activator of conidiation brlA, indicating a direct repressive role of NsdD in conidiation. Importantly, loss of flbC or flbD encoding upstream activators of brlA in the absence of nsdD results in delayed activation of brlA, suggesting distinct positive roles of FlbC and FlbD in conidiation. A genetic model depicting regulation of conidiation in A. nidulans is presented. PMID:27364479

  5. Comparative genomics of citric-acid producing Aspergillus niger ATCC 1015 versus enzyme-producing CBS 513.88

    Energy Technology Data Exchange (ETDEWEB)

    Grigoriev, Igor V.; Baker, Scott E.; Andersen, Mikael R.; Salazar, Margarita P.; Schaap, Peter J.; Vondervoot, Peter J.I. van de; Culley, David; Thykaer, Jette; Frisvad, Jens C.; Nielsen, Kristen F.; Albang, Richard; Albermann, Kaj; Berka, Randy M.; Braus, Gerhard H.; Braus-Stromeyer, Susanna A.; Corrochano, Luis M.; Dai, Ziyu; Dijck, Piet W.M. van; Hofmann, Gerald; Lasure, Linda L.; Magnusson, Jon K.; Meijer, Susan L.; Nielsen, Jakob B.; Nielsen, Michael L.; Ooyen, Albert J.J. van; Panther, Kathyrn S.; Pel, Herman J.; Poulsen, Lars; Samson, Rob A.; Stam, Hen; Tsang, Adrian; Brink, Johannes M. van den; Atkins, Alex; Aerts, Andrea; Shapiro, Harris; Pangilinan, Jasmyn; Salamov, Asaf; Lou, Yigong; Lindquist, Erika; Lucas, Susan; Grimwood, Jane; Kubicek, Christian P.; Martinez, Diego; Peij, Noel N.M.E. van; Roubos, Johannes A.; Nielsen, Jens

    2011-04-28

    The filamentous fungus Aspergillus niger exhibits great diversity in its phenotype. It is found globally, both as marine and terrestrial strains, produces both organic acids and hydrolytic enzymes in high amounts, and some isolates exhibit pathogenicity. Although the genome of an industrial enzyme-producing A. niger strain (CBS 513.88) has already been sequenced, the versatility and diversity of this species compels additional exploration. We therefore undertook whole genome sequencing of the acidogenic A. niger wild type strain (ATCC 1015), and produced a genome sequence of very high quality. Only 15 gaps are present in the sequence and half the telomeric regions have been elucidated. Moreover, sequence information from ATCC 1015 was utilized to improve the genome sequence of CBS 513.88. Chromosome-level comparisons uncovered several genome rearrangements, deletions, a clear case of strain-specific horizontal gene transfer, and identification of 0.8 megabase of novel sequence. Single nucleotide polymorphisms per kilobase (SNPs/kb) between the two strains were found to be exceptionally high (average: 7.8, maximum: 160 SNPs/kb). High variation within the species was confirmed with exo-metabolite profiling and phylogenetics. Detailed lists of alleles were generated, and genotypic differences were observed to accumulate in metabolic pathways essential to acid production and protein synthesis. A transcriptome analysis revealed up-regulation of the electron transport chain, specifically the alternative oxidative pathway in ATCC 1015, while CBS 513.88 showed significant up-regulation of genes relevant to glucoamylase A production, such as tRNA-synthases and protein transporters. Our results and datasets from this integrative systems biology analysis resulted in a snapshot of fungal evolution and will support further optimization of cell factories based on filamentous fungi.[Supplemental materials (10 figures, three text documents and 16 tables) have been made available

  6. Biotransformation von 11-Desoxycortisol mit Schizosaccharomyces pombe und Aspergillus nidulans

    OpenAIRE

    Appel, Daniel

    2005-01-01

    In diesem Projekt, welches in Kooperation mit dem Institut für Biochemie der Universität des Saarlandes und der Schering AG Bergkamen durchgeführt wurde, sollte mit Hilfe von rekombinanten Spalthefestämmen, welche die humane Monooxygenase P450 CYP11B1 exprimieren, eine nachhaltigere Bio-Produktion von Hydrocortison entwickelt werden, um das bestehende Verfahren der Hydrocortisonherstellung, mittels des filamentösen Pilz Curvularia lunata zu ersetzen. Um die Optimierung der Hydrocortisonpro...

  7. Inducible RNA Interference of brlAβ in Aspergillus nidulans▿

    Science.gov (United States)

    Barton, L. M.; Prade, R. A.

    2008-01-01

    An inducible RNA interference (RNAi) construct composed of inverted repeating alcA promoters flanking the developmental regulatory gene brlAβ was tested in Aspergillus nidulans. On inducing medium, the RNAi strains failed to sporulate and lacked brlAα and brlAβ expression. RNAi was specific for brlAβ, but not brlAα, silencing, indicating brlAα regulation by brlAβ. PMID:18757565

  8. Genome Shuffling of Mangrove Endophytic Aspergillus luchuensis MERV10 for Improving the Cholesterol-Lowering Agent Lovastatin under Solid State Fermentation

    Science.gov (United States)

    El-Gendy, Mervat Morsy Abbas Ahmed; Al-Zahrani, Hind A. A.

    2016-01-01

    In the screening of marine mangrove derived fungi for lovastatin productivity, endophytic Aspergillus luchuensis MERV10 exhibited the highest lovastatin productivity (9.5 mg/gds) in solid state fermentation (SSF) using rice bran. Aspergillus luchuensis MERV10 was used as the parental strain in which to induce genetic variabilities after application of different mixtures as well as doses of mutagens followed by three successive rounds of genome shuffling. Four potent mutants, UN6, UN28, NE11, and NE23, with lovastatin productivity equal to 2.0-, 2.11-, 1.95-, and 2.11-fold higher than the parental strain, respectively, were applied for three rounds of genome shuffling as the initial mutants. Four hereditarily stable recombinants (F3/3, F3/7, F3/9, and F3/13) were obtained with lovastatin productivity equal to 50.8, 57.0, 49.7, and 51.0 mg/gds, respectively. Recombinant strain F3/7 yielded 57.0 mg/gds of lovastatin, which is 6-fold and 2.85-fold higher, respectively, than the initial parental strain and the highest mutants UN28 and NE23. It was therefore selected for the optimization of lovastatin production through improvement of SSF parameters. Lovastatin productivity was increased 32-fold through strain improvement methods, including mutations and three successive rounds of genome shuffling followed by optimizing SSF factors.

  9. Recombinant bacterial hemoglobin alters metabolism of Aspergillus niger

    DEFF Research Database (Denmark)

    Hofmann, Gerald; Diano, Audrey; Nielsen, Jens

    2009-01-01

    The filamentous fungus Aspergillus niger is used extensively for the production of enzymes and organic acids. A major problem in industrial fermentations with this fungus is to ensure sufficient supply of oxygen required for respiratory metabolism of the fungus. In case of oxygen limitation...... behind the strong gpdA promoter from Aspergillus nidulans. Analysis of secreted metabolites, oxygen uptake, CO2 evolution and biomass formation points towards a relief of stress in the mutant expressing VHB when it is exposed to oxygen limitation. Our findings therefore point to an interesting strategy...

  10. Chemodiversity in the genus Aspergillus.

    Science.gov (United States)

    Frisvad, Jens C; Larsen, Thomas O

    2015-10-01

    Isolates of Aspergillus species are able to produce a large number of secondary metabolites. The profiles of biosynthetic families of secondary metabolites are species specific, whereas individual secondary metabolite families can occur in other species, even those phylogenetically and ecologically unrelated to Aspergillus. Furthermore, there is a high degree of chemo-consistency from isolate to isolate in a species even though certain metabolite gene clusters are silenced in some isolates. Genome sequencing projects have shown that the diversity of secondary metabolites is much larger in each species than previously thought. The potential of finding even further new bioactive drug candidates in Aspergillus is evident, despite the fact that many secondary metabolites have already been structure elucidated and chemotaxonomic studies have shown that many new secondary metabolites have yet to be characterized. The genus Aspergillus is cladistically holophyletic but phenotypically polythetic and very diverse and is associated to quite different sexual states. Following the one fungus one name system, the genus Aspergillus is restricted to a holophyletic clade that include the morphologically different genera Aspergillus, Dichotomomyces, Phialosimplex, Polypaecilum and Cristaspora. Secondary metabolites common between the subgenera and sections of Aspergillus are surprisingly few, but many metabolites are common to a majority of species within the sections. We call small molecule extrolites in the same biosynthetic family isoextrolites. However, it appears that secondary metabolites from one Aspergillus section have analogous metabolites in other sections (here also called heteroisoextrolites). In this review, we give a genus-wide overview of secondary metabolite production in Aspergillus species. Extrolites appear to have evolved because of ecological challenges rather than being inherited from ancestral species, at least when comparing the species in the different

  11. Effect of culture temperature on the heterologous expression of Pleurotus eryngii versatile peroxidase in Aspergillus hosts.

    Science.gov (United States)

    Eibes, G M; Lú-Chau, T A; Ruiz-Dueñas, F J; Feijoo, G; Martínez, M J; Martínez, A T; Lema, J M

    2009-01-01

    Production of recombinant versatile peroxidase in Aspergillus hosts was optimized through the modification of temperature during bioreactor cultivations. To further this purpose, the cDNA encoding a versatile peroxidase of Pleurotus eryngii was expressed under control of the alcohol dehydrogenase (alcA) promoter of Aspergillus nidulans. A dependence of recombinant peroxidase production on cultivation temperature was found. Lowering the culture temperature from 28 to 19 degrees C enhanced the level of active peroxidase 5.8-fold and reduced the effective proteolytic activity twofold. Thus, a maximum peroxidase activity of 466 U L(-1) was reached. The same optimization scheme was applied to a recombinant Aspergillus niger that bore the alcohol dehydrogenase regulator (alcR), enabling transformation with the peroxidase cDNA under the same alcA promoter. However, with this strain, the peroxidase activity was not improved, while the effective proteolytic activity was increased between 3- and 11-fold compared to that obtained with A. nidulans.

  12. Use of functional genomics to assess the impact of climate change on Aspergillus flavus and aflatoxin production

    Science.gov (United States)

    Aspergillus flavus is an opportunistic pathogenic fungus that infects several crops of agricultural importance, among them, corn, cotton, and peanuts. Once established as a pathogen the fungus may secrete secondary metabolites commonly known as mycotoxins, that if consumed by humans or animals may r...

  13. Quantitative trait locus (QTL mapping reveals a role for unstudied genes in Aspergillus virulence.

    Directory of Open Access Journals (Sweden)

    Julian K Christians

    Full Text Available Infections caused by the fungus Aspergillus are a major cause of morbidity and mortality in immunocompromised populations. To identify genes required for virulence that could be used as targets for novel treatments, we mapped quantitative trait loci (QTL affecting virulence in the progeny of a cross between two strains of A. nidulans (FGSC strains A4 and A91. We genotyped 61 progeny at 739 single nucleotide polymorphisms (SNP spread throughout the genome, and constructed a linkage map that was largely consistent with the genomic sequence, with the exception of one potential inversion of ∼527 kb on Chromosome V. The estimated genome size was 3705 cM and the average intermarker spacing was 5.0 cM. The average ratio of physical distance to genetic distance was 8.1 kb/cM, which is similar to previous estimates, and variation in recombination rate was significantly positively correlated with GC content, a pattern seen in other taxa. To map QTL affecting virulence, we measured the ability of each progeny strain to kill model hosts, larvae of the wax moth Galleria mellonella. We detected three QTL affecting in vivo virulence that were distinct from QTL affecting in vitro growth, and mapped the virulence QTL to regions containing 7-24 genes, excluding genes with no sequence variation between the parental strains and genes with only synonymous SNPs. None of the genes in our QTL target regions have been previously associated with virulence in Aspergillus, and almost half of these genes are currently annotated as "hypothetical". This study is the first to map QTL affecting the virulence of a fungal pathogen in an animal host, and our results illustrate the power of this approach to identify a short list of unknown genes for further investigation.

  14. The Glucose-6-phosphate dehydrogenase encoding genes from Aspergillus niger and Aspergillus nidulans.

    NARCIS (Netherlands)

    Broek, van den P.J.M.

    1997-01-01

    Glucose-6-phosphate (G6P) is a central metabolite, that can either be metabolised via the glycolytic and tricarboxylic acid cycle to generate ATP, or converted into storage molecules or can be directed to the pentose phosphate pathway to yield NADPH and various pentoses. This thesis focuses on one o

  15. Antifungal activity of oregano extract against A. Versicolor, E. Nidulans and Eurotium spp.: Producers of sterigmatocystin

    Directory of Open Access Journals (Sweden)

    Kocić-Tanackov Sunčica D.

    2011-01-01

    Full Text Available The paper presents the influence of oregano extract (Origanum vulgare L. on growth of Aspergillus versicolor, Emericella nidulans, Eurotium herbariorum, E. amstelodami, E. chevalieri and E. rubrum - producers of sterigmatocystin (STC isolated from salads. Antifungal tests were performed by agar plates method. The composition of the active component of extract was determined by GC-MS method and the major components were: carvacrol (34.20%, triacetin (22.91%, carvone (18.05%, p-cymene (8.05% and thymol (3.74%. The examined extract showed the ability to reduce mold growth at all applied concentrations. Minimum inhibitory concentrations (MIC for E. nidulans, E. chevalieri and E. amstelodami were 2.5% (v/v and over 2.5% (v/v for A. versicolor. At 1.5% (v/v concentration the extract completely inhibited the growth of E. rubrum, whereas higher dose of 2.5% (v/v was fungicidal against E. herbariorum. Besides its sensory role in food products, the examined oregano extract also exhibits antifungal activities against producers of STC.

  16. Fine de novo sequencing of a fungal genome using only SOLiD short read data: verification on Aspergillus oryzae RIB40.

    Directory of Open Access Journals (Sweden)

    Myco Umemura

    Full Text Available The development of next-generation sequencing (NGS technologies has dramatically increased the throughput, speed, and efficiency of genome sequencing. The short read data generated from NGS platforms, such as SOLiD and Illumina, are quite useful for mapping analysis. However, the SOLiD read data with lengths of <60 bp have been considered to be too short for de novo genome sequencing. Here, to investigate whether de novo sequencing of fungal genomes is possible using only SOLiD short read sequence data, we performed de novo assembly of the Aspergillus oryzae RIB40 genome using only SOLiD read data of 50 bp generated from mate-paired libraries with 2.8- or 1.9-kb insert sizes. The assembled scaffolds showed an N50 value of 1.6 Mb, a 22-fold increase than those obtained using only SOLiD short read in other published reports. In addition, almost 99% of the reference genome was accurately aligned by the assembled scaffold fragments in long lengths. The sequences of secondary metabolite biosynthetic genes and clusters, whose products are of considerable interest in fungal studies due to their potential medicinal, agricultural, and cosmetic properties, were also highly reconstructed in the assembled scaffolds. Based on these findings, we concluded that de novo genome sequencing using only SOLiD short reads is feasible and practical for molecular biological study of fungi. We also investigated the effect of filtering low quality data, library insert size, and k-mer size on the assembly performance, and recommend for the assembly use of mild filtered read data where the N50 was not so degraded and the library has an insert size of ∼2.0 kb, and k-mer size 33.

  17. rtfA, a putative RNA-Pol II transcription elongation factor, is necessary for normal morphological and chemical development in Aspergillus flavus

    Science.gov (United States)

    The filamentous fungus Aspergillus flavus is an agriculturally important opportunistic plant pathogen that produces potent carcinogenic compounds called aflatoxins. We identified the A. flavus rtfA gene, the ortholog of rtf1 in S. cerevisiae and rtfA in A. nidulans. Interestingly, rtfA has multiple ...

  18. 甘肃省土壤曲霉属(Aspergillus Mich.ex Link:Fr.)的种%Aspergillus spp. in Soil of Gansu Province

    Institute of Scientific and Technical Information of China (English)

    刘艳梅; 朱建兰

    2005-01-01

    对140份来自甘肃各地的土样进行曲霉属(Aspergillus Mich.ex Link:Fr.)菌的分离,结合菌落形态及显微镜下孢子的形态将各菌鉴定到种.结果表明:甘肃省土壤中分布有7个种和3个变种.分别是烟曲霉原变种(Aspergillus fumigatus var.fumigatus)、烟曲霉椭孢变种(Aspergtllus fumigatus var.ellipticus)、烟束曲霉(Aspergillus fumisynnematus)、黄曲霉原变种(Aspergillus flflavus var.flavus)、寄生曲霉(Aspergillus parasiticus)、刺孢裸胞壳(Emericella echinulata)、构巢裸胞壳(Emericella nidulans var.nidulans)、褶皱裸胞壳(Emericella rugulosa)、四脊裸胞壳(Emericella quadrilineata)及皱折裸胞壳(Emericella corrugata).

  19. Transcriptional profiling of Aspergillus niger

    NARCIS (Netherlands)

    Veen, van der D.

    2009-01-01

    The industrially important fungus Aspergillus niger feeds naturally on decomposing plant material, of which a significant proportion is lipid. Examination of the A. niger genome sequence suggested that all proteins required for metabolic conversion of lipids are present, including 63 predicted lipas

  20. Aspergillus: sex and recombination.

    Science.gov (United States)

    Varga, János; Szigeti, Gyöngyi; Baranyi, Nikolett; Kocsubé, Sándor; O'Gorman, Céline M; Dyer, Paul S

    2014-12-01

    The genus Aspergillus is one of the most widespread groups of fungi on Earth, comprised of about 300-350 species with very diverse lifestyles. Most species produce asexual propagula (conidia) on conidial heads. Despite their ubiquity, a sexual cycle has not yet been identified for most of the aspergilli. Where sexual reproduction is present, species exhibit either homothallic (self fertile) or heterothallic (obligate outcrossing) breeding systems. A parasexual cycle has also been described in some Aspergillus species. As in other fungi, sexual reproduction is governed by mating-type (MAT) genes, which determine sexual identity and are involved in regulating later stages of sexual development. Previous population genetic studies have indicated that some supposedly asexual aspergilli exhibit evidence of a recombining population structure, suggesting the presence of a cryptic sexual cycle. In addition, genome analyses have revealed networks of genes necessary for sexual reproduction in several Aspergillus species, again consistent with latent sexuality in these fungi. Knowledge of MAT gene presence has then successfully been applied to induce sexual reproduction between MAT1-1 and MAT1-2 isolates of certain supposedly asexual aspergilli. Recent progress in understanding the extent and significance of sexual reproduction is described here, with special emphasis on findings that are relevant to clinically important aspergilli. PMID:25118872

  1. Purification and enzymatic characterization of secretory glycoside hydrolase family 3 (GH3) aryl β-glucosidases screened from Aspergillus oryzae genome.

    Science.gov (United States)

    Kudo, Kanako; Watanabe, Akira; Ujiie, Seiryu; Shintani, Takahiro; Gomi, Katsuya

    2015-12-01

    By a global search of the genome database of Aspergillus oryzae, we found 23 genes encoding putative β-glucosidases, among which 10 genes with a signal peptide belonging to glycoside hydrolase family 3 (GH3) were overexpressed in A. oryzae using the improved glaA gene promoter. Consequently, crude enzyme preparations from three strains, each harboring the genes AO090038000223 (bglA), AO090103000127 (bglF), and AO090003001511 (bglJ), showed a substrate preference toward p-nitrophenyl-β-d-glucopyranoside (pNPGlc) and thus were purified to homogeneity and enzymatically characterized. All the purified enzymes (BglA, BglF, and BglJ) preferentially hydrolyzed aryl β-glycosides, including pNPGlc, rather than cellobiose, and these enzymes were proven to be aryl β-glucosidases. Although the specific activity of BglF toward all the substrates tested was significantly low, BglA and BglJ showed appreciably high activities toward pNPGlc and arbutin. The kinetic parameters of BglA and BglJ for pNPGlc suggested that both the enzymes had relatively higher hydrolytic activity toward pNPGlc among the fungal β-glucosidases reported. The thermal and pH stabilities of BglA were higher than those of BglJ, and BglA was particularly stable in a wide pH range (pH 4.5-10). In contrast, BglJ was the most heat- and alkaline-labile among the three β-glucosidases. Furthermore, BglA was more tolerant to ethanol than BglJ; as a result, it showed much higher hydrolytic activity toward isoflavone glycosides in the presence of ethanol than BglJ. This study suggested that the mining of novel β-glucosidases exhibiting higher activity from microbial genome sequences is of great use for the production of beneficial compounds such as isoflavone aglycones. PMID:25936960

  2. Genome-Wide Transcriptome Analysis of Cotton (Gossypium hirsutum L. Identifies Candidate Gene Signatures in Response to Aflatoxin Producing Fungus Aspergillus flavus.

    Directory of Open Access Journals (Sweden)

    Renesh Bedre

    Full Text Available Aflatoxins are toxic and potent carcinogenic metabolites produced from the fungi Aspergillus flavus and A. parasiticus. Aflatoxins can contaminate cottonseed under conducive preharvest and postharvest conditions. United States federal regulations restrict the use of aflatoxin contaminated cottonseed at >20 ppb for animal feed. Several strategies have been proposed for controlling aflatoxin contamination, and much success has been achieved by the application of an atoxigenic strain of A. flavus in cotton, peanut and maize fields. Development of cultivars resistant to aflatoxin through overexpression of resistance associated genes and/or knocking down aflatoxin biosynthesis of A. flavus will be an effective strategy for controlling aflatoxin contamination in cotton. In this study, genome-wide transcriptome profiling was performed to identify differentially expressed genes in response to infection with both toxigenic and atoxigenic strains of A. flavus on cotton (Gossypium hirsutum L. pericarp and seed. The genes involved in antifungal response, oxidative burst, transcription factors, defense signaling pathways and stress response were highly differentially expressed in pericarp and seed tissues in response to A. flavus infection. The cell-wall modifying genes and genes involved in the production of antimicrobial substances were more active in pericarp as compared to seed. The genes involved in auxin and cytokinin signaling were also induced. Most of the genes involved in defense response in cotton were highly induced in pericarp than in seed. The global gene expression analysis in response to fungal invasion in cotton will serve as a source for identifying biomarkers for breeding, potential candidate genes for transgenic manipulation, and will help in understanding complex plant-fungal interaction for future downstream research.

  3. Genome-Wide Transcriptome Analysis of Cotton (Gossypium hirsutum L.) Identifies Candidate Gene Signatures in Response to Aflatoxin Producing Fungus Aspergillus flavus.

    Science.gov (United States)

    Bedre, Renesh; Rajasekaran, Kanniah; Mangu, Venkata Ramanarao; Sanchez Timm, Luis Eduardo; Bhatnagar, Deepak; Baisakh, Niranjan

    2015-01-01

    Aflatoxins are toxic and potent carcinogenic metabolites produced from the fungi Aspergillus flavus and A. parasiticus. Aflatoxins can contaminate cottonseed under conducive preharvest and postharvest conditions. United States federal regulations restrict the use of aflatoxin contaminated cottonseed at >20 ppb for animal feed. Several strategies have been proposed for controlling aflatoxin contamination, and much success has been achieved by the application of an atoxigenic strain of A. flavus in cotton, peanut and maize fields. Development of cultivars resistant to aflatoxin through overexpression of resistance associated genes and/or knocking down aflatoxin biosynthesis of A. flavus will be an effective strategy for controlling aflatoxin contamination in cotton. In this study, genome-wide transcriptome profiling was performed to identify differentially expressed genes in response to infection with both toxigenic and atoxigenic strains of A. flavus on cotton (Gossypium hirsutum L.) pericarp and seed. The genes involved in antifungal response, oxidative burst, transcription factors, defense signaling pathways and stress response were highly differentially expressed in pericarp and seed tissues in response to A. flavus infection. The cell-wall modifying genes and genes involved in the production of antimicrobial substances were more active in pericarp as compared to seed. The genes involved in auxin and cytokinin signaling were also induced. Most of the genes involved in defense response in cotton were highly induced in pericarp than in seed. The global gene expression analysis in response to fungal invasion in cotton will serve as a source for identifying biomarkers for breeding, potential candidate genes for transgenic manipulation, and will help in understanding complex plant-fungal interaction for future downstream research. PMID:26366857

  4. Study on the molecular basis of glucoamylase overproduc-tion of a mutant strain Aspergillus niger T21

    Institute of Scientific and Technical Information of China (English)

    FAN; Xiaochun

    2001-01-01

    [1]Qiao, D., Tang, G., Zhong, L. et al., The overall analysis and comparison of the expression of glucoamylase in the over-production strain A. niger T21 and its original strain A. niger 3.795, Acta Microbiologica Sinica (in Chinese), 1997, 37(5): 349.[2]Zhong, L, Qiao, D, Tang, G. et al., Cloning, sequencing and comparison of the 5′-flanking regions of glaA gene from high and low glucoamylase producing strains of Aspergillus niger, Acta Microbiologica Sinica (in Chinese), 1996, 36: 181.[3]Qiao, D., Zhong, L., Tang, G. et al., Cloning and sequencing of glucoamylase gene from Aspergillus niger 3.795, Chinese J. Biochem. and Mol. Biology (in Chinese), 1998, 14: 254.[4]Zhong, L., Fan, X., Tang, G., Cotransformation of glucoamylase overproducing strain Aspergillus niger T21 with niaD and uidA gene, Mycosystema (in Chinese), 1999, 18: 172.[5]Roberts, I. N., Oliver, R. P., Punt, P. J. et al., Expression of the Escherichia coli b-glucuronidase gene in industrial and phytopathogenic filamentous fungi, Curr. Genet., 1989, 15: 177.[6]Lowry, O. H., Rosebrough, N. J., Farr, A. L. et al., Protein measurement with the folin phenol reagent, J. Biochem., 1951, 193: 268.[7]Zhu, H., Qu, F., Zhu, L., Isolation of genomic DNAs from fungi using benzyl chloride, Acta Mycologica Sinica (in Chi-nese), 1994, 13: 34.[8]Verwoerd, T. C., Dekker, B. M. M., Hoekema, A., A small-scale procedure for the rapid isolation of plant RNAs, Nucleic Acids Research, 1989, 17: 2362.[9]Campbell, E. I., Unkles, S. E., Marco, J. A. et al., Improved transformation efficiency of Aspergillus niger using the ho-mologous niaD gene for nitrate reductase, Curr. Genet., 1989, 16: 53.[10]Fowler, T., Berka, R. M., Ward, M., Regulation of the glaA gene of Aspergillus niger, Curr. Genet., 1990, 18: 537.[11]Verdoes, J. C., Punt, P. J., Stouthamer, A. H. et al., The effect of multiple copies of the upstream region on expression of the Aspergillus niger glucoamylase

  5. Transcriptional profiling of Aspergillus niger

    OpenAIRE

    Veen, van der, J.T.

    2009-01-01

    The industrially important fungus Aspergillus niger feeds naturally on decomposing plant material, of which a significant proportion is lipid. Examination of the A. niger genome sequence suggested that all proteins required for metabolic conversion of lipids are present, including 63 predicted lipases. In contrast to polysaccharide-degrading enzyme networks, not much is known about the signaling and regulatory processes that control lipase expression and activity in fungi. This project was ai...

  6. Conserved secondary structures in Aspergillus.

    Directory of Open Access Journals (Sweden)

    Abigail Manson McGuire

    Full Text Available BACKGROUND: Recent evidence suggests that the number and variety of functional RNAs (ncRNAs as well as cis-acting RNA elements within mRNAs is much higher than previously thought; thus, the ability to computationally predict and analyze RNAs has taken on new importance. We have computationally studied the secondary structures in an alignment of six Aspergillus genomes. Little is known about the RNAs present in this set of fungi, and this diverse set of genomes has an optimal level of sequence conservation for observing the correlated evolution of base-pairs seen in RNAs. METHODOLOGY/PRINCIPAL FINDINGS: We report the results of a whole-genome search for evolutionarily conserved secondary structures, as well as the results of clustering these predicted secondary structures by structural similarity. We find a total of 7450 predicted secondary structures, including a new predicted approximately 60 bp long hairpin motif found primarily inside introns. We find no evidence for microRNAs. Different types of genomic regions are over-represented in different classes of predicted secondary structures. Exons contain the longest motifs (primarily long, branched hairpins, 5' UTRs primarily contain groupings of short hairpins located near the start codon, and 3' UTRs contain very little secondary structure compared to other regions. There is a large concentration of short hairpins just inside the boundaries of exons. The density of predicted intronic RNAs increases with the length of introns, and the density of predicted secondary structures within mRNA coding regions increases with the number of introns in a gene. CONCLUSIONS/SIGNIFICANCE: There are many conserved, high-confidence RNAs of unknown function in these Aspergillus genomes, as well as interesting spatial distributions of predicted secondary structures. This study increases our knowledge of secondary structure in these aspergillus organisms.

  7. Aspergillus niger genome-wide analysis reveals a large number of novel alpha-glucan acting enzymes with unexpected expression profiles

    NARCIS (Netherlands)

    Yuan, X.-L.; Kaaij, R.M. van der; Hondel, C.A.M.J.J. van den; Punt, P.J.; Maarel, M.J.E.C. van der; Dijkhuizen, L.; Ram, A.F.J.

    2008-01-01

    The filamentous ascomycete Aspergillus niger is well known for its ability to produce a large variety of enzymes for the degradation of plant polysaccharide material. A major carbon and energy source for this soil fungus is starch, which can be degraded by the concerted action of α-amylase, glucoamy

  8. The two genome sequence release and blast server construction for aflatoxin-producing L and S strains Aspergillus parasiticus and A. flavus

    Science.gov (United States)

    Aflatoxins are toxic and carcinogenic secondary metabolites. These compounds, produced by Aspergillus flavus and A. parasiticus, contaminate pre-harvest agricultural crops in the field and post-harvest grains during storage. In order to reduce and eliminate aflatoxin contamination of food and feed...

  9. Reconstruction of the central carbon metabolism of Aspergillus niger

    DEFF Research Database (Denmark)

    David, Helga; Åkesson, Mats Fredrik; Nielsen, Jens

    2003-01-01

    The topology of central carbon metabolism of Aspergillus niger was identified and the metabolic network reconstructed, by integrating genomic, biochemical and physiological information available for this microorganism and other related fungi. The reconstructed network may serve as a valuable...

  10. RNA-Seq analysis of stuA mutants in Fusarium verticillioides indicates dramatic genomic wide transcriptional reprogramming

    Science.gov (United States)

    StuA, first discovered in Aspergillus nidulans and a member of the APSES class of transcription factors, regulates several essential developmental stages in fungi such as virulence, sporulation and toxin production in phytopathogenic fungi. Fusarium verticillioides (Fv), a maize phytopathogen, produ...

  11. Picosecond energy transfer in Porphyridium cruentum and Anacystis nidulans.

    OpenAIRE

    Brody, S. S.; Treadwell, C; Barber, J

    1981-01-01

    Picosecond energy transfer is measured in Anacystis nidulans and Porphyridium cruentum. Fluorescence is sensitized by a 6-ps laser flash, at 530 nm. The time dependence of fluorescence is measured with reference to the laser pulse. Fluorescence is recorded from phycoerythrin (576 nm), R-phycocyanin (640 nm), allophycocyanin (666 nm), Photosystem II chlorophyll (690 nm) and long wave length chlorophyll (715 nm). Energy transfer measurements are made at 37 degrees C, 23 degrees C, and 0 degrees...

  12. Isolation and identification of Aspergillus spp. from brown kiwi (Apteryx mantelli) nocturnal houses in New Zealand.

    Science.gov (United States)

    Glare, Travis R; Gartrell, Brett D; Brookes, Jenny J; Perrott, John K

    2014-03-01

    Aspergillosis, a disease caused by infection with Aspergillus spp., is a common cause of death in birds globally and is an irregular cause of mortality of captive kiwi (Apteryx spp.). Aspergillus spp. are often present in rotting plant material, including the litter and nesting material used for kiwi in captivity. The aim of this study was to survey nocturnal kiwi houses in New Zealand to assess the levels of Aspergillus currently present in leaf litter. Samples were received from 11 nocturnal kiwi houses from throughout New Zealand, with one site supplying multiple samples over time. Aspergillus was isolated and quantified by colony counts from litter samples using selective media and incubation temperatures. Isolates were identified to the species level by amplification and sequencing of ITS regions of the ribosomal. Aspergillus spp. were recovered from almost every sample; however, the levels in most kiwi houses were below 1000 colony-forming units (CFU)/g of wet material. The predominant species was Aspergillus fumigatus, with rare occurrences of Aspergillus niger, Aspergillus nidulans, and Aspergillus parasiticus. Only one site had no detectable Aspergillus. The limit of detection was around 50 CFU/g wet material. One site was repeatedly sampled as it had a high loading of A. fumigatus at the start of the survey and had two recent clinical cases of aspergillosis diagnosed in resident kiwi. Environmental loading at this site with Aspergillus spp. reduced but was not eliminated despite changes of the litter. The key finding of our study is that the background levels of Aspergillus spores in kiwi nocturnal houses in New Zealand are low, but occasional exceptions occur and are associated with the onset of aspergillosis in otherwise healthy birds. The predominant Aspergillus species present in the leaf litter was A. fumigatus, but other species were also present. Further research is needed to confirm the optimal management of leaf litter to minimize Aspergillus

  13. Survey and analysis of simple sequence repeats in the Laccaria bicolor genome, with development of microsatellite markers

    Energy Technology Data Exchange (ETDEWEB)

    Labbe, Jessy L [ORNL; Murat, Claude [INRA, Nancy, France; Morin, Emmanuelle [INRA, Nancy, France; Le Tacon, F [UMR, France; Martin, Francis [INRA, Nancy, France

    2011-01-01

    It is becoming clear that simple sequence repeats (SSRs) play a significant role in fungal genome organization, and they are a large source of genetic markers for population genetics and meiotic maps. We identified SSRs in the Laccaria bicolor genome by in silico survey and analyzed their distribution in the different genomic regions. We also compared the abundance and distribution of SSRs in L. bicolor with those of the following fungal genomes: Phanerochaete chrysosporium, Coprinopsis cinerea, Ustilago maydis, Cryptococcus neoformans, Aspergillus nidulans, Magnaporthe grisea, Neurospora crassa and Saccharomyces cerevisiae. Using the MISA computer program, we detected 277,062 SSRs in the L. bicolor genome representing 8% of the assembled genomic sequence. Among the analyzed basidiomycetes, L. bicolor exhibited the highest SSR density although no correlation between relative abundance and the genome sizes was observed. In most genomes the short motifs (mono- to trinucleotides) were more abundant than the longer repeated SSRs. Generally, in each organism, the occurrence, relative abundance, and relative density of SSRs decreased as the repeat unit increased. Furthermore, each organism had its own common and longest SSRs. In the L. bicolor genome, most of the SSRs were located in intergenic regions (73.3%) and the highest SSR density was observed in transposable elements (TEs; 6,706 SSRs/Mb). However, 81% of the protein-coding genes contained SSRs in their exons, suggesting that SSR polymorphism may alter gene phenotypes. Within a L. bicolor offspring, sequence polymorphism of 78 SSRs was mainly detected in non-TE intergenic regions. Unlike previously developed microsatellite markers, these new ones are spread throughout the genome; these markers could have immediate applications in population genetics.

  14. Genome-Wide Transcriptome Analysis of Cotton (Gossypium hirsutum L.) Identifies Candidate Gene Signatures in Response to Aflatoxin Producing Fungus Aspergillus flavus

    OpenAIRE

    Bedre, Renesh; Rajasekaran, Kanniah; Mangu, Venkata Ramanarao; Sanchez Timm, Luis Eduardo; Bhatnagar, Deepak; Baisakh, Niranjan

    2015-01-01

    Aflatoxins are toxic and potent carcinogenic metabolites produced from the fungi Aspergillus flavus and A. parasiticus. Aflatoxins can contaminate cottonseed under conducive preharvest and postharvest conditions. United States federal regulations restrict the use of aflatoxin contaminated cottonseed at >20 ppb for animal feed. Several strategies have been proposed for controlling aflatoxin contamination, and much success has been achieved by the application of an atoxigenic strain of A. flavu...

  15. Reducing fitness costs associated with antibiotic resistance: experimental evolution in the filamentous fungus Aspergillus nidulans

    OpenAIRE

    Schoustra, S.E.

    2004-01-01

    The 1990s saw the growth of two distinct strands of debates on the transformations and emerging problems besetting the urban space. One of these has focused on the relationship between globalisation and the similar changes metropolitan cities are undergoing, as they become home to numerous global economic agents such as multinational firms. According to it, globalisation can be understood as a worldwide reaching 'space of flows' - of money, information, and physical streams - emerging within ...

  16. Large-Scale Metabolomics Reveals A Complex Response of Aspergillus nidulans to Epigenetic Perturbation

    OpenAIRE

    Albright, Jessica C.; Henke, Matthew T.; Soukup, Alexandra A.; McClure, Ryan A.; Thomson, Regan J.; Keller, Nancy P.; Kelleher, Neil L.

    2015-01-01

    The microbial world offers a rich source of bioactive compounds for those able to sift through it. Technologies capable of quantitatively detecting natural products while simultaneously identifying known compounds would expedite the search for new pharmaceutical leads. Prior efforts have targeted histone deacetylases in fungi to globally activate the production of new secondary metabolites, yet no study has directly assessed its effects with minimal bias at the metabolomic level. Using untarg...

  17. Spectroscopic Evidence for the Two C-H-Cleaving Intermediates of Aspergillus nidulans Isopenicillin N Synthase.

    Science.gov (United States)

    Tamanaha, Esta; Zhang, Bo; Guo, Yisong; Chang, Wei-Chen; Barr, Eric W; Xing, Gang; St Clair, Jennifer; Ye, Shengfa; Neese, Frank; Bollinger, J Martin; Krebs, Carsten

    2016-07-20

    The enzyme isopenicillin N synthase (IPNS) installs the β-lactam and thiazolidine rings of the penicillin core into the linear tripeptide l-δ-aminoadipoyl-l-Cys-d-Val (ACV) on the pathways to a number of important antibacterial drugs. A classic set of enzymological and crystallographic studies by Baldwin and co-workers established that this overall four-electron oxidation occurs by a sequence of two oxidative cyclizations, with the β-lactam ring being installed first and the thiazolidine ring second. Each phase requires cleavage of an aliphatic C-H bond of the substrate: the pro-S-CCys,β-H bond for closure of the β-lactam ring, and the CVal,β-H bond for installation of the thiazolidine ring. IPNS uses a mononuclear non-heme-iron(II) cofactor and dioxygen as cosubstrate to cleave these C-H bonds and direct the ring closures. Despite the intense scrutiny to which the enzyme has been subjected, the identities of the oxidized iron intermediates that cleave the C-H bonds have been addressed only computationally; no experimental insight into their geometric or electronic structures has been reported. In this work, we have employed a combination of transient-state-kinetic and spectroscopic methods, together with the specifically deuterium-labeled substrates, A[d2-C]V and AC[d8-V], to identify both C-H-cleaving intermediates. The results show that they are high-spin Fe(III)-superoxo and high-spin Fe(IV)-oxo complexes, respectively, in agreement with published mechanistic proposals derived computationally from Baldwin's founding work.

  18. Effect of secretory pathway gene overexpression on secretion of a fluorescent reporter protein in Aspergillus nidulans

    DEFF Research Database (Denmark)

    Schalén, Martin; Anyaogu, Diana Chinyere; Hoof, Jakob Blæsbjerg;

    2016-01-01

    . The background strain was a fluorescent reporter secreting mRFP. The overall effect of the overexpressions could thus be easily monitored through fluorescence measurements, while the effects on physiology were determined in batch cultivations and surface growth studies. Results: Fourteen protein secretion...... pathway related genes were overexpressed with a tet-ON promoter in the RFP-secreting reporter strain and macromorphology, physiology and protein secretion were monitored when the secretory genes were induced. Overexpression of several of the chosen genes was shown to cause anomalies on growth, micro...... results indicate that increased expression may be a way for the cell to slow down secretion in order to cope with the increased protein load. By constructing a secretion reporter strain, the study demonstrates a robust way to study the secretion pathway in filamentous fungi....

  19. Aspergillus nidulans ArfB Plays a Role in Endocytosis and Polarized Growth ▿ †

    OpenAIRE

    Lee, Soo Chan; Schmidtke, Sabrina N.; Dangott, Lawrence J.; Shaw, Brian D.

    2008-01-01

    Filamentous fungi undergo polarized growth throughout most of their life cycles. The Spitzenkörper is an apical organelle composed primarily of vesicles that is unique to filamentous fungi and is likely to act as a vesicle supply center for tip growth. Vesicle assembly and trafficking are therefore important for hyphal growth. ADP ribosylation factors (Arfs), a group of small GTPase proteins, play an important role in nucleating vesicle assembly. Little is known about the role of Arfs in fila...

  20. Reducing fitness costs associated with antibiotic resistance: experimental evolution in the filamentous fungus Aspergillus nidulans

    NARCIS (Netherlands)

    Schoustra, S.E.

    2004-01-01

    The 1990s saw the growth of two distinct strands of debates on the transformations and emerging problems besetting the urban space. One of these has focused on the relationship between globalisation and the similar changes metropolitan cities are undergoing, as they become home to numerous global ec

  1. Studies of the Production of Fungal Polyketides in Aspergillus nidulans by Using Systems Biology Tools

    DEFF Research Database (Denmark)

    Panagiotou, Gianni; Andersen, Mikael Rørdam; Grotkjær, Thomas;

    2009-01-01

    -methylsalicylic acid (6-MSA) synthase gene and one expressing the 6-MSA synthase gene and overexpressing the native xylulose-5-phosphate phosphoketolase gene (xpkA) for increasing the pool of polyketide precursor levels. The physiology of the recombinant strains and that of a reference wild-type strain were...... characterized on glucose, xylose, glycerol, and ethanol media in controlled bioreactors. Glucose was found to be the preferred carbon source for 6-MSA production, and 6-MSA concentrations up to 455 mg/liter were obtained for the recombinant strain harboring the 6-MSA gene. Our findings indicate...... that overexpression of xpkA does not directly improve 6-MSA production on glucose, but it is possible, if the metabolic flux through the lower part of glycolysis is reduced, to obtain quite high yields for conversion of sugar to 6-MSA. Systems biology tools were employed for in-depth analysis of the metabolic...

  2. Genetic and physical mapping of two centromere-proximal regions of chromosome IV in Aspergillus nidulans

    DEFF Research Database (Denmark)

    Aleksenko, Alexei Y.; Nielsen, Michael Lynge; Clutterbuck, A.J.

    2001-01-01

    revision of the genetic map of the chromosome, including the position of the centromere, Comparison of physical and genetic maps indicates that meiotic recombination is low in subcentromeric DNA, its frequency being reduced from 1 crossover per 0.8 Mb to approximately 1 crossover per 5 Mb per meiosis...

  3. Aspergillus spp.in Soil of Gansu Longnan and Tianshui%甘肃省陇南、天水林区土壤曲霉属种的研究

    Institute of Scientific and Technical Information of China (English)

    杨航宇; 吕志鹏

    2006-01-01

    对100 份来自陇南、天水林区的土样进行曲霉属(Aspergillus Mich.ex Link:Fr.)菌的分离,结合菌落形态及显微镜下孢子的形态将各菌鉴定到种.结果表明:甘肃省陇南、天水林区土壤中分布有6 个种和4 个变种.分别是烟曲霉原变种(Aspergillus fumigatus var.fumigatus)、烟曲霉椭孢变种(Aspergillus fumigatus var.ellipticus)、土曲霉原变种(Aspergillus terreus)、杂色曲霉原变种(Aspergillus versicolor)、刺孢裸胞壳(Emericella echinulata)、构巢裸胞壳(Emericella nidulans var.nidulans)、褶皱裸胞壳(Emericella rugulosa)、四脊裸胞壳(Emericella quadrilineata)、茴香裸胞壳(Emericella foeniculicola)及矮棒曲霉(Aspergillus cavatonaicus).

  4. Diversity, molecular phylogeny and fingerprint profiles of airborne Aspergillus species using random amplified polymorphic DNA.

    Science.gov (United States)

    Kermani, Firoozeh; Shams-Ghahfarokhi, Masoomeh; Gholami-Shabani, Mohammadhassan; Razzaghi-Abyaneh, Mehdi

    2016-06-01

    In the present study, diversity and phylogenetic relationship of Aspergillus species isolated from Tehran air was studied using random amplified polymorphic DNA (RAPD)-polymerase chain reaction (RAPD-PCR). Thirty-eight Aspergillus isolates belonging to 12 species i.e. A. niger (28.94 %, 11 isolates), A. flavus (18.42 %, 7 isolates), A. tubingensis (13.15 %, 5 isolates), A. japonicus (10.52 %, 4 isolates), A. ochraceus (10.52 %, 4 isolates), and 2.63 %, 1 isolate from each A. nidulans, A. amstelodami, A. oryzae, A. terreus, A. versicolor, A. flavipes and A. fumigatus were obtained by settle plate method which they were distributed in 18 out of 22 sampling sites examined. Fungal DNA was extracted from cultured mycelia of all Aspergillus isolates on Sabouraud Dextrose Agar and used for amplification of gene fragments in RAPD-PCR using 11 primers. RAPD-PCR data was analyzed using UPGMA software. Resulting dendrogram of combined selected primers including PM1, OPW-04, OPW-05, P160, P54, P10 and OPA14 indicated the distribution of 12 Aspergillus species in 8 major clusters. The similarity coefficient of all 38 Aspergillus isolates ranged from 0.02 to 0.40 indicating a wide degree of similarities and differences within and between species. Taken together, our results showed that various Aspergillus species including some important human pathogenic ones exist in the outdoor air of Tehran by different extents in distribution and diversity and suggested inter- and intra-species genetic diversity among Aspergillus species by RAPD-PCR as a rapid, sensitive and reproducible method. PMID:27116962

  5. Fine De Novo Sequencing of a Fungal Genome Using only SOLiD Short Read Data: Verification on Aspergillus oryzae RIB40

    OpenAIRE

    Myco Umemura; Yoshinori Koyama; Itaru Takeda; Hiroko Hagiwara; Tsutomu Ikegami; Hideaki Koike; Masayuki Machida

    2013-01-01

    The development of next-generation sequencing (NGS) technologies has dramatically increased the throughput, speed, and efficiency of genome sequencing. The short read data generated from NGS platforms, such as SOLiD and Illumina, are quite useful for mapping analysis. However, the SOLiD read data with lengths of

  6. Aspergillus as a multi-purpose cell factory: current status and perspectives.

    Science.gov (United States)

    Meyer, Vera; Wu, Bo; Ram, Arthur F J

    2011-03-01

    Aspergilli have a long history in biotechnology as expression platforms for the production of food ingredients, pharmaceuticals and enzymes. The achievements made during the last years, however, have the potential to revolutionize Aspergillus biotechnology and to assure Aspergillus a dominant place among microbial cell factories. This mini-review will highlight most recent breakthroughs in fundamental and applied Aspergillus research with a focus on new molecular tools, techniques and products. New trends and concepts related to Aspergillus genomics and systems biology will be discussed as well as the challenges that have to be met to integrate omics data with metabolic engineering attempts.

  7. (+)-Geodin from Aspergillus terreus

    DEFF Research Database (Denmark)

    Rønnest, Mads Holger; Nielsen, Morten Thrane; Leber, Blanka;

    2011-01-01

    The fungal metabolite (+)-geodin [systematic name: (2R)-methyl 5,7-dichloro-4-hydroxy-6'-methoxy-6-methyl-3,4'-dioxospiro[benzofuran-2,1'-cyclohexa-2',5'-diene]-2'-carboxylate], C(17)H(12)Cl(2)O(7), was isolated from Aspergillus terreus. The crystal structure contains two independent molecules...

  8. Disinfection efficacy of chlorine and peracetic acid alone or in combination against Aspergillus spp. and Candida albicans in drinking water.

    Science.gov (United States)

    Sisti, Maurizio; Brandi, Giorgio; De Santi, Mauro; Rinaldi, Laura; Schiavano, Giuditta F

    2012-03-01

    The aim of the present study was to evaluate the fungicidal activity of chlorine and peracetic acid in drinking water against various pathogenic Aspergillus spp. and Candida albicans strains. A. nidulans exhibited the greatest resistance, requiring 10 ppm of chlorine for 30 min contact time for a complete inactivation. Under the same experimental conditions, peracetic acid was even less fungicidal. In this case, A. niger proved to be the most resistant species (50 ppm for 60 min for complete inactivation). All Aspergillus spp. were insensitive to 10 ppm even with extended exposure (>5 h). The combination of chlorine and peracetic acid against Aspergillus spp. did not show synergistic effects except in the case of A. flavus. Complete growth inhibition of C. albicans was observed after about 3 h contact time with 0.2 ppm. C. albicans was less sensitive to peracetic acid. Hence the concentrations of chlorine that are usually present in drinking water distribution systems are ineffective against several Aspergillus spp. and peracetic acid cannot be considered an alternative to chlorine for disinfecting drinking water. The combination of the two biocides is not very effective in eliminating filamentous fungi at the concentrations permitted for drinking water disinfection.

  9. Single Strand Conformation Polymorphism analysis of PCR-amplified rDNA to differentiate medically important Aspergillus Species

    Directory of Open Access Journals (Sweden)

    K Diba

    2008-09-01

    Full Text Available "nBackground: Aspergillus species are associated with allergic bronchopulmonary disease, mycotic keratitis, otomycosis, na­sal sinusitis and invasive infection. In this study, we developed a PCR-Single Strand Confomational Polymorphism method to identify the most common Aspergillus species and we showed some advantages of this method comparing a PCR-Restric­tion Fragment Length Polymorphism with our designed restriction enzyme. "nMethods: We selected ITS2, as a short fragment within the rDNA region (length size: 330 bp to be amplified as small size PCR product. We mixed 5 ml of the PCR product with an equal volume of loading buffer and followed by incubation for 5 min at 95º C and quenching in an ice bath. The mixture was applied to a 6%-12% Gradient Poly acryl amide gel to run in a verti­cal electrophoresis, then gel was stained with ethidium bromide and silver nitrate which followed by an ethidium bro­mide staining. "nResults: Our results of restriction digestion showed a fine identification of 7 tested Aspergillus species dur­ing 5-6 hours af­ter an overnight mycelial growth. As our results some of tested Aspergillus species: A. nidulans, A. fisheri, A. quad­ricincta, (A. fumigatus and A. niger as a group and (A. flavus, A. tereus and A. ochraceus as another group, can be dis­criminated. More­over SSCP analysis enabled us to identify above Aspergillus species within 8-12 h after an over night growth without us­ing an expensive restriction enzyme."nConclusion: It is concluded that Single Strand Conformational Polymorphism is a simple and rapid method for identifica­tion of some medically important Aspergillus.

  10. Toward systems metabolic engineering of Aspergillus and Pichia species for the production of chemicals and biofuels

    DEFF Research Database (Denmark)

    Caspeta, Luis; Nielsen, Jens

    2013-01-01

    such as random mutagenesis to a systems level which decreases the time and efforts on design and implementation. Here, the authors review the recent trends in systems biology of Aspergillus and Pichia species, highlighting the relevance of developments for systems metabolic engineering of these organisms......Recently genome sequence data have become available for Aspergillus and Pichia species of industrial interest. This has stimulated the use of systems biology approaches for large-scale analysis of the molecular and metabolic responses of Aspergillus and Pichia under defined conditions, which has...... of knowledge on the fundamental biology of Aspergillus and Pichia species. Furthermore, with the availability of these models, the engineering of Aspergillus and Pichia is moving from traditional approaches, such as random mutagenesis, to a systems metabolic engineering approach. Here we review the recent...

  11. Modern taxonomy of biotechnologically important Aspergillus and Penicillium species.

    Science.gov (United States)

    Houbraken, Jos; de Vries, Ronald P; Samson, Robert A

    2014-01-01

    Taxonomy is a dynamic discipline and name changes of fungi with biotechnological, industrial, or medical importance are often difficult to understand for researchers in the applied field. Species belonging to the genera Aspergillus and Penicillium are commonly used or isolated, and inadequate taxonomy or uncertain nomenclature of these genera can therefore lead to tremendous confusion. Misidentification of strains used in biotechnology can be traced back to (1) recent changes in nomenclature, (2) new taxonomic insights, including description of new species, and/or (3) incorrect identifications. Changes in the recent published International Code of Nomenclature for Algae, Fungi and Plants will lead to numerous name changes of existing Aspergillus and Penicillium species and an overview of the current names of biotechnological important species is given. Furthermore, in (biotechnological) literature old and invalid names are still used, such as Aspergillus awamori, A. foetidus, A. kawachii, Talaromyces emersonii, Acremonium cellulolyticus, and Penicillium funiculosum. An overview of these and other species with their correct names is presented. Furthermore, the biotechnologically important species Talaromyces thermophilus is here combined in Thermomyces as Th. dupontii. The importance of Aspergillus, Penicillium, and related genera is also illustrated by the high number of undertaken genome sequencing projects. A number of these strains are incorrectly identified or atypical strains are selected for these projects. Recommendations for correct strain selection are given here. Phylogenetic analysis shows a close relationship between the genome-sequenced strains of Aspergillus, Penicillium, and Monascus. Talaromyces stipitatus and T. marneffei (syn. Penicillium marneffei) are closely related to Thermomyces lanuginosus and Th. dupontii (syn. Talaromyces thermophilus), and these species appear to be distantly related to Aspergillus and Penicillium. In the last part of

  12. In vitro susceptibility testing of Aspergillus spp. against voriconazole, itraconazole, posaconazole, amphotericin B and caspofungin

    Institute of Scientific and Technical Information of China (English)

    SHI Jun-yan; WANG He; GUO Li-na; XU Ying-chun; SHI Yi; L(U) Huo-xiang; LIU Yong; ZHAO Wang-sheng; CHEN Dong-mei; XI Li-yan; ZHOU Xin

    2010-01-01

    Background During recent years, the incidence of serious infections caused by opportunistic fungi has increased dramatically due to alterations of the immune status of patients with hematological diseases, malignant tumors,transplantations and so forth. Unfortunately, the wide use of triazole antifungal agents to treat these infections has lead to the emergence of Aspergillus spp. resistant to triazoles. The present study was to assess the in vitro activities of five antifungal agents (voriconazole, itraconazole, posaconazole, amphotericin B and caspofungin) against different kinds of Aspergillus spp. that are commonly encountered in the clinical setting.Methods The agar-based Etest MIC method was employed. One hundred and seven strains of Aspergillus spp. (5 species) were collected and prepared according to Etest Technique Manuel. Etest MICs were determined with RPMI agar containing 2% glucose and were read after incubation for 48 hours at 35℃. MIC50, MIC90 and MIC range were acquired by Whonet 5.4 software.Results The MIC90 of caspofungin against A. fumigatus, A. flavus and A. nidulans was 0.094 μg/ml whereas the MIC90 against A. niger was 0.19 μg/ml. For these four species, the MlC90 of caspofungin was the lowest among the five antifungal agents. For A. terrus, the MIC90 of posaconazole was the lowest. For A. fumigatus and A. flavus, the MlC90in order of increasing was caspofungin, posaconazole, voriconazole, itraconazole, and amphotericin B. The MIC of amphotericin B against A. terrus was higher than 32 μg/ml in all 7 strains tested.Conclusions The in vitro antifungal susceptibility test shows the new drug caspofungin, which is a kind of echinocandins, has good activity against the five species of Aspergillus spp. and all the triazoles tested have better in vitro activity than traditional amphotericin B.

  13. Lytic polysaccharide monooxygenases and other oxidative enzymes are abundantly secreted by Aspergillus nidulans grown on different starches

    DEFF Research Database (Denmark)

    Nekiunaite, Laura; Arntzen, Magnus Ø.; Svensson, Birte;

    2016-01-01

    by amylolytic activity measurements. Nearly half of the 312 proteins in the secretomes were carbohydrate-active enzymes (CAZymes), mostly glycoside hydrolases (GHs) and oxidative auxiliary activities (AAs). The abundance of the GH13 α-amylase (AmyB) decreased with time, as opposed to other starch......-degrading enzymes, e.g., the GH13 AmyF, GH15 glucoamylases (GlaA and GlaB), and the GH31 α-glucosidase (AgdE). Two AA13 LPMOs displayed similar secretion patterns as amylolytic hydrolases and were among the most abundant CAZymes. The starch-active AnLPMO13A that possesses a CBM20 carbohydrate-binding module...... dominated the starch-binding secretome fraction. A striking observation is the co-secretion of several redox-active enzymes with the starch-active AA13 LPMOs and GHs, some at high abundance. Notably nine AA9 LPMOs, six AA3 sub-family 2 (AA_2) oxidoreductases, and ten AA7 glyco-oligosaccharide oxidases were...

  14. Aspergillus nidulans α-galactosidase of glycoside hydrolase family 36 catalyses the formation of α-galacto-oligosaccharides by transglycosylation

    DEFF Research Database (Denmark)

    Nakai, Hiroyuki; Baumann, Martin; Petersen, B. O.;

    2010-01-01

    not transglycosylate monosaccharides without the 6-hydroxymethyl group, i.e. xylose, l-arabinose, l-fucose and l-rhamnose, or with axial 3-OH, i.e. gulose, allose, altrose and l-rhamnose. Structural modelling using Thermotoga maritima GH36 α-galactosidase as the template and superimposition of melibiose from...

  15. Aspergillus niger RhaR, a regulator involved in L-rhamnose release and catabolism

    NARCIS (Netherlands)

    Gruben, B.S.; Zhou, M.; Wiebenga, A.; Ballering, J.; Overkamp, K.M.; Punt, P.J.; Vries, R.P. de

    2014-01-01

    The genome of the filamentous fungus Aspergillus niger is rich in genes encoding pectinases, a broad class of enzymes that have been extensively studied due to their use in industrial applications. The sequencing of the A. niger genome provided more knowledge concerning the individual pectinolytic g

  16. Aspergillus saccharolyticus sp. nov., a new black Aspergillus species isolated in Denmark

    DEFF Research Database (Denmark)

    Sørensen, Annette; Lübeck, Peter S.; Lübeck, Mette;

    2011-01-01

    A novel species, Aspergillus saccharolyticus sp. nov., belonging to the Aspergillus section Nigri group is described. This species was isolated in Denmark from treated hardwood. Its taxonomic status was determined using a polyphasic taxonomic approach including phenotypic (morphology and extrolite...... Aspergillus species that is morphologically similar to Aspergillus japonicus and Aspergillus aculeatus, but has a totally different extrolite profile compared to any known Aspergillus species. The type strain of A. saccharolyticus sp. nov. is CBS 127449T ( = IBT 28509T)....

  17. Aspergillus fumigatus in Poultry

    Directory of Open Access Journals (Sweden)

    Pascal Arné

    2011-01-01

    Full Text Available Aspergillus fumigatus remains a major respiratory pathogen in birds. In poultry, infection by A. fumigatus may induce significant economic losses particularly in turkey production. A. fumigatus develops and sporulates easily in poor quality bedding or contaminated feedstuffs in indoor farm environments. Inadequate ventilation and dusty conditions increase the risk of bird exposure to aerosolized spores. Acute cases are seen in young animals following inhalation of spores, causing high morbidity and mortality. The chronic form affects older birds and looks more sporadic. The respiratory tract is the primary site of A. fumigatus development leading to severe respiratory distress and associated granulomatous airsacculitis and pneumonia. Treatments for infected poultry are nonexistent; therefore, prevention is the only way to protect poultry. Development of avian models of aspergillosis may improve our understanding of its pathogenesis, which remains poorly understood.

  18. Aspergillus-Related Lung Disease

    Directory of Open Access Journals (Sweden)

    Alia Al-Alawi

    2005-01-01

    Full Text Available Aspergillus is a ubiquitous dimorphic fungus that causes a variety of human diseases ranging in severity from trivial to life-threatening, depending on the host response. An intact host defence is important to prevent disease, but individuals with pre-existing structural lung disease, atopy, occupational exposure or impaired immunity are susceptible. Three distinctive patterns of aspergillus-related lung disease are recognized: saprophytic infestation of airways, cavities and necrotic tissue; allergic disease including extrinsic allergic alveolitis, asthma, allergic bronchopulmonary aspergillosis, bronchocentric granulomatosis and chronic eosinophilic pneumonia; and airway and tissue invasive disease -- pseudomembranous tracheobronchitis, acute bronchopneumonia, angioinvasive aspergillosis, chronic necrotizing aspergillosis and invasive pleural disease. A broad knowledge of these clinical presentations and a high index of suspicion are required to ensure timely diagnosis and treatment of the potentially lethal manifestations of aspergillus-related pulmonary disease. In the present report, the clinical, radiographic and pathological aspects of the various aspergillus-related lung diseases are briefly reviewed.

  19. Update on antifungal drug resistance mechanisms of Aspergillus fumigatus.

    Science.gov (United States)

    Chamilos, G; Kontoyiannis, D P

    2005-12-01

    Although the arsenal of agents with anti-Aspergillus activity has expanded over the last decade, mortality due to invasive aspergillosis (IA) remains unacceptably high. Aspergillus fumigatus still accounts for the majority of cases of IA; however less susceptible to antifungals non-fumigatus aspergilli began to emerge. Antifungal drug resistance of Aspergillus might partially account for treatment failures. Recent advances in our understanding of mechanisms of antifungal drug action in Aspergillus, along with the standardization of in vitro susceptibility testing methods, has brought resistance testing to the forefront of clinical mycology. In addition, molecular biology has started to shed light on the mechanisms of resistance of A. fumigatus to azoles and the echinocandins, while genome-based assays show promise for high-throughput screening for genotypic antifungal resistance. Several problems remain, however, in the study of this complex area. Large multicenter clinical studies--point prevalence or longitudinal--to capture the incidence and prevalence of antifungal resistance in A. fumigatus isolates are lacking. Correlation of in vitro susceptibility with clinical outcome and susceptibility breakpoints has not been established. In addition, the issue of cross-resistance between the newer triazoles is of concern. Furthermore, in vitro resistance testing for polyenes and echinocandins is difficult, and their mechanisms of resistance are largely unknown. This review examines challenges in the diagnosis, epidemiology, and mechanisms of antifungal drug resistance in A. fumigatus. PMID:16488654

  20. Gene Expression Profiling and Identification of Resistance Genes to Aspergillus flavus Infection in Peanut through EST and Microarray Strategies

    Directory of Open Access Journals (Sweden)

    Baozhu Guo

    2011-06-01

    Full Text Available Aspergillus flavus and A. parasiticus infect peanut seeds and produce aflatoxins, which are associated with various diseases in domestic animals and humans throughout the world. The most cost-effective strategy to minimize aflatoxin contamination involves the development of peanut cultivars that are resistant to fungal infection and/or aflatoxin production. To identify peanut Aspergillus-interactive and peanut Aspergillus-resistance genes, we carried out a large scale peanut Expressed Sequence Tag (EST project which we used to construct a peanut glass slide oligonucleotide microarray. The fabricated microarray represents over 40% of the protein coding genes in the peanut genome. For expression profiling, resistant and susceptible peanut cultivars were infected with a mixture of Aspergillus flavus and parasiticus spores. The subsequent microarray analysis identified 62 genes in resistant cultivars that were up-expressed in response to Aspergillus infection. In addition, we identified 22 putative Aspergillus-resistance genes that were constitutively up-expressed in the resistant cultivar in comparison to the susceptible cultivar. Some of these genes were homologous to peanut, corn, and soybean genes that were previously shown to confer resistance to fungal infection. This study is a first step towards a comprehensive genome-scale platform for developing Aspergillus-resistant peanut cultivars through targeted marker-assisted breeding and genetic engineering.

  1. Vaccination approaches against opportunistic fungal infections caused by Aspergillus fumigatus.

    Science.gov (United States)

    Reichard, Utz; Herrmann, Sahra; Asif, Abdul R

    2014-01-01

    Although innate immunity primarily combats systemic infections of opportunistic fungi such as Aspergillus and Candida spp., acquired and protective immunoreactions were observed long ago in animal trials following sublethal systemic infections caused by viable fungi or after challenging animals with inactivated fungal cells. Based on these observations, fungal antigens should exist which mediate such protective immunoreactions and have in part already been identified. In this context, this review focuses primarily on the various approaches that have been used to identify protection-mediating Aspergillus-antigens and their rationale. Emphasis is placed on screening methods that have exploited genetic or proteomic approaches on the basis of the corresponding fungal genome projects. Thereby, a survey and description is given of the antigens so far known to be capable of inducing immune responses that protect animals against acquiring lethal systemic aspergillosis.

  2. Regulatory processes in Aspergillus niger

    DEFF Research Database (Denmark)

    Poulsen, Lars

    Filamentous fungi are extensively used in the fermentation industry for synthesis of numerous products. One of the most important, is the fungus Aspergillus niger, used industrially for production of organic acids, and homologous as well as heterologous enzymes. This fungus has numerous of advant......Filamentous fungi are extensively used in the fermentation industry for synthesis of numerous products. One of the most important, is the fungus Aspergillus niger, used industrially for production of organic acids, and homologous as well as heterologous enzymes. This fungus has numerous...

  3. Enhanced diversity and aflatoxigenicity in interspecific hybrids of Aspergillus flavus and Aspergillus parasiticus.

    Science.gov (United States)

    Olarte, Rodrigo A; Worthington, Carolyn J; Horn, Bruce W; Moore, Geromy G; Singh, Rakhi; Monacell, James T; Dorner, Joe W; Stone, Eric A; Xie, De-Yu; Carbone, Ignazio

    2015-04-01

    Aspergillus flavus and A. parasiticus are the two most important aflatoxin-producing fungi responsible for the contamination of agricultural commodities worldwide. Both species are heterothallic and undergo sexual reproduction in laboratory crosses. Here we examine the possibility of interspecific matings between A. flavus and A. parasiticus. These species can be distinguished morphologically and genetically, as well as by their mycotoxin profiles. Aspergillus flavus produces both B aflatoxins and cyclopiazonic acid (CPA), B aflatoxins or CPA alone, or neither mycotoxin; Aspergillus parasiticus produces B and G aflatoxins or the aflatoxin precursor O-methylsterigmatocystin, but not CPA. Only four of forty-five attempted interspecific crosses between opposite mating types of A. flavus and A. parasiticus were fertile and produced viable ascospores. Single ascospore strains from each cross were shown to be recombinant hybrids using multilocus genotyping and array comparative genome hybridization. Conidia of parents and their hybrid progeny were haploid and predominantly monokaryons and dikaryons based on flow cytometry. Multilocus phylogenetic inference showed that experimental hybrid progeny were grouped with naturally occurring A. flavus L strain and A. parasiticus. Higher total aflatoxin concentrations in some F1 progeny strains compared to midpoint parent aflatoxin levels indicate synergism in aflatoxin production; moreover, three progeny strains synthesized G aflatoxins that were not produced by the parents, and there was evidence of allopolyploidization in one strain. These results suggest that hybridization is an important diversifying force resulting in the genesis of novel toxin profiles in these agriculturally important fungi.

  4. Transcriptional organization of the phycocyanin subunit gene clusters of the cyanobacterium Anacystis nidulans UTEX 625.

    OpenAIRE

    Kalla, S R; Lind, L K; Lidholm, J; Gustafsson, P

    1988-01-01

    The phycocyanin subunit gene cluster is duplicated on the chromosome of the cyanobacterium Anacystis nidulans UTEX 625. The two gene clusters cpcB1A1 (left) and cpcB2A2 (right) are separated by about 2,500 base pairs, and in each cluster the beta-subunit gene is located upstream from the alpha-subunit gene. Filter hybridizations with phycocyanin-specific probes to total RNA detected at least two major transcripts that were 1,300 to 1,400 nucleotides long. Besides these major mRNA species, two...

  5. Aspergillus flavus Blast2GO gene ontology database: elevated growth temperature alters amino acid metabolism

    Science.gov (United States)

    The availability of a representative gene ontology (GO) database is a prerequisite for a successful functional genomics study. Using online Blast2GO resources we constructed a GO database of Aspergillus flavus. Of the predicted total 13,485 A. flavus genes 8,987 were annotated with GO terms. The mea...

  6. The molecular and genetic basis of conidial pigmentation in Aspergillus niger

    DEFF Research Database (Denmark)

    Jørgensen, Thomas R.; Park, Joohae; Arentshorst, Mark;

    2011-01-01

    A characteristic hallmark of Aspergillus niger is the formation of black conidiospores. We have identified four loci involved in spore pigmentation of A. niger by using a combined genomic and classical complementation approach. First, we characterized a newly isolated color mutant, colA, which la...

  7. Database mining and transcriptional analysis of genes encoding inulin-modifying enzymes of Aspergillus niger

    NARCIS (Netherlands)

    Yuan, X.L.; Goosen, C.; Kools, H.J.; Maarel, van der M.J.; Hondel, van den C.A.M.J.J.; Dijkhuizen, L.; Ram, A.F.

    2006-01-01

    As a soil fungus, Aspergillus niger can metabolize a wide variety of carbon sources, employing sets of enzymes able to degrade plant-derived polysaccharides. In this study the genome sequence of A. niger strain CBS 513.88 was surveyed, to analyse the gene/enzyme network involved in utilization of th

  8. Molecular and biochemical characterization of a novel intracellular invertase from Aspergillus niger with transfructosylating activity

    NARCIS (Netherlands)

    Yuan, Xiao-Lian; van Munster, Jolanda M.; Ram, Arthur F. J.; van der Maarel, Marc J. E. C.; Dijkhuizen, Lubbert; Goosen, C.

    2007-01-01

    A novel subfamily of putative intracellular invertase enzymes (glycoside hydrolase family 32) has previously been identified in fungal genomes. Here, we report phylogenetic, molecular, and biochemical characteristics of SucB, one of two novel intracellular invertases identified in Aspergillus niger.

  9. Identification and characterization of glycoside hydrolase family 32 enzymes from Aspergillus niger

    NARCIS (Netherlands)

    Goosen, Coenie

    2007-01-01

    This thesis focuses on the identification and characterization of sucrose and fructan modifying enzymes present in the genome of the industrially important filamentous fungus, Aspergillus niger. In addition to three known activities, encoded by the genes suc1 (invertase activity; designated sucA), i

  10. 76 FR 16297 - Aspergillus flavus

    Science.gov (United States)

    2011-03-23

    ... exemptions for experimental use of Aspergillus flavus AF36 on pistachio (72 FR 28871, May 23, 2007) (FRL-8129... Findings In the Federal Register of March 3, 2010 (75 FR 9596) (FRL-8811-2), EPA issued a notice pursuant..., 2003 (68 FR 41541) (FRL-7311-6). Those health effects data were the basis for establishing...

  11. Aspergillus infections in cystic fibrosis.

    Science.gov (United States)

    King, Jill; Brunel, Shan F; Warris, Adilia

    2016-07-01

    Patients with cystic fibrosis (CF) suffer from chronic lung infection and airway inflammation. Respiratory failure secondary to chronic or recurrent infection remains the commonest cause of death and accounts for over 90% of mortality. Bacteria as Staphylococcus aureus, Pseudomonas aeruginosa and Burkholderia cepacia complex have been regarded the main CF pathogens and their role in progressive lung decline has been studied extensively. Little attention has been paid to the role of Aspergillus spp. and other filamentous fungi in the pathogenesis of non-ABPA (allergic bronchopulmonary aspergillosis) respiratory disease in CF, despite their frequent recovery in respiratory samples. It has become more apparent however, that Aspergillus spp. may play an important role in chronic lung disease in CF. Research delineating the underlying mechanisms of Aspergillus persistence and infection in the CF lung and its link to lung deterioration is lacking. This review summarizes the Aspergillus disease phenotypes observed in CF, discusses the role of CFTR (cystic fibrosis transmembrane conductance regulator)-protein in innate immune responses and new treatment modalities. PMID:27177733

  12. Aspergillus mediastinitis after cardiac surgery

    Directory of Open Access Journals (Sweden)

    Marie-Josée Caballero

    2016-03-01

    Conclusion: The clinical features of postoperative Aspergillus mediastinitis may be paucisymptomatic, emphasizing the need for a low index of suspicion in cases of culture-negative mediastinitis or in indolent wound infections. In addition to surgical debridement, the central component of antifungal therapy should include amphotericin B or voriconazole.

  13. Cloning of a third nitrate reductase gene from the cyanobacterium Anacystis nidulans R2 using a shuttle cosmid library

    NARCIS (Netherlands)

    Kuhlemeier, C.J.; Teeuwsen, V.J.P.; Janssen, M.J.T.; Arkel, G.A. van

    1984-01-01

    A strategy for gene cloning in the cyanobacterium Anacystis nidulans R2 was developed which made use of a gene library constructed in a shuttle cosmid vector. The method involved phenotypic complementation of mutants with pooled cosmid DNA. The development of the procedure and its application to the

  14. DNA apophotolyase from Anacystis nidulans: 1.8 A structure, 8-HDF reconstitution and X-ray-induced FAD reduction.

    NARCIS (Netherlands)

    R. Kort; H. Komori; S. Adachi; K. Miki; A. Eker

    2004-01-01

    DNA photolyase is a unique flavoenzyme that repairs UV-induced DNA lesions using the energy of visible light. Anacystis nidulans photolyase contains a light-harvesting chromophore, 8-hydroxy-5-deazaflavin (8-HDF), and flavin adenine dinucleotide (FAD) which, in contrast to the 8-HDF chromophore, is

  15. Biodegradation of phenol by Antarctic strains of Aspergillus fumigatus.

    Science.gov (United States)

    Gerginova, Maria; Manasiev, Jordan; Yemendzhiev, Husein; Terziyska, Anna; Peneva, Nadejda; Alexieva, Zlatka

    2013-01-01

    Taxonomic identification of three newly isolated Antarctic fungal strains by their 18S rDNA sequences revealed their affiliation with Aspergillus fumigatus. Phenol (0.5 g/l) as the sole carbon source was completely degraded by all strains within less than two weeks. Intracellular activities of three key enzymes involved in the phenol catabolism were determined. Activities of phenol hydroxylase (EC 1.14.13.7), hydroquinone hydroxylase (EC 1.14.13.x), and catechol 1,2-dioxygenase (EC 1.13.11.1) varied significantly between strains. The rates of phenol degradation in the three strains correlated best with the activity of catechol 1,2-dioxygenase. Six pairs of oligonucleotide primers were designed on the basis of the Aspergillus fumigatus Af293 genome sequence (NCBI Acc. No. XM_743491.1) and used to amplify phenol hydroxylase-related gene sequences. DNA sequences of about 1200 bp were amplified from all three strains and found to have a high degree of sequence identity with the corresponding gene of Aspergillus fumigatus Af293.

  16. Involvement of the opportunistic pathogen Aspergillus tubingensis in osteomyelitis of the maxillary bone : a case report

    NARCIS (Netherlands)

    Bathoorn, Erik; Salazar, Natalia Escobar; Sepehrkhouy, Shahrzad; Meijer, Martin; de Cock, Hans; Haas, Pieter-Jan

    2013-01-01

    Background: Aspergillus tubingensis is a black Aspergillus belonging to the Aspergillus section Nigri, which includes species that morphologically resemble Aspergillus niger. Recent developments in species determination have resulted in clinical isolates presumed to be Aspergillus niger being reclas

  17. RmtA, a Putative Arginine Methyltransferase, Regulates Secondary Metabolism and Development in Aspergillus flavus

    Science.gov (United States)

    Satterlee, Timothy; Cary, Jeffrey W.; Calvo, Ana M.

    2016-01-01

    Aspergillus flavus colonizes numerous oil seed crops such as corn, peanuts, treenuts and cotton worldwide, contaminating them with aflatoxin and other harmful potent toxins. In the phylogenetically related model fungus Aspergillus nidulans, the methyltransferase, RmtA, has been described to be involved in epigenetics regulation through histone modification. Epigenetics regulation affects a variety of cellular processes, including morphogenesis and secondary metabolism. Our study shows that deletion of rmtA in A. flavus results in hyperconidiating colonies, indicating that rmtA is a repressor of asexual development in this fungus. The increase in conidiation in the absence of rmtA coincides with greater expression of brlA, abaA, and wetA compared to that in the wild type. Additionally, the rmtA deletion mutant presents a drastic reduction or loss of sclerotial production, while forced expression of this gene increased the ability of this fungus to generate these resistant structures, revealing rmtA as a positive regulator of sclerotial formation. Importantly, rmtA is also required for the production of aflatoxin B1 in A. flavus, affecting the expression of aflJ. Furthermore, biosynthesis of additional metabolites is also controlled by rmtA, indicating a broad regulatory output in the control of secondary metabolism. This study also revealed that rmtA positively regulates the expression of the global regulatory gene veA, which could contribute to mediate the effects of rmtA on development and secondary metabolism in this relevant opportunistic plant pathogen. PMID:27213959

  18. Ochratoxin A-Produktion durch Aspergillus ochraceus

    OpenAIRE

    Mühlencoert, Ellen

    2006-01-01

    Ochratoxin A, one of the 5 most important mycotoxins in food safety, is produced by several Aspergillus and Penicillium strains growing on grain, grapes and coffee. OTA biosynthesis in Aspergillus spp. depends more on the complex interaction of diverse environmental conditions than on a single growth factor or even the genetic ability to produce OTA. No apparent connection between biomass and OTA production was observed. OTA production by Aspergillus ochraceus could be controlled by the pH of...

  19. Overexpression of Aspergillus tubingensis faeA in protease-deficient Aspergillus niger enables ferulic acid production from plant material.

    Science.gov (United States)

    Zwane, Eunice N; Rose, Shaunita H; van Zyl, Willem H; Rumbold, Karl; Viljoen-Bloom, Marinda

    2014-06-01

    The production of ferulic acid esterase involved in the release of ferulic acid side groups from xylan was investigated in strains of Aspergillus tubingensis, Aspergillus carneus, Aspergillus niger and Rhizopus oryzae. The highest activity on triticale bran as sole carbon source was observed with the A. tubingensis T8.4 strain, which produced a type A ferulic acid esterase active against methyl p-coumarate, methyl ferulate and methyl sinapate. The activity of the A. tubingensis ferulic acid esterase (AtFAEA) was inhibited twofold by glucose and induced twofold in the presence of maize bran. An initial accumulation of endoglucanase was followed by the production of endoxylanase, suggesting a combined action with ferulic acid esterase on maize bran. A genomic copy of the A. tubingensis faeA gene was cloned and expressed in A. niger D15#26 under the control of the A. niger gpd promoter. The recombinant strain has reduced protease activity and does not acidify the media, therefore promoting high-level expression of recombinant enzymes. It produced 13.5 U/ml FAEA after 5 days on autoclaved maize bran as sole carbon source, which was threefold higher than for the A. tubingensis donor strain. The recombinant AtFAEA was able to extract 50 % of the available ferulic acid from non-pretreated maize bran, making this enzyme suitable for the biological production of ferulic acid from lignocellulosic plant material.

  20. Atypical Aspergillus parasiticus isolates from pistachio with aflR gene nucleotide insertion identical to Aspergillus sojae

    Science.gov (United States)

    Aflatoxins are the most toxic and carcinogenic secondary metabolites produced primarily by the filamentous fungi Aspergillus flavus and Aspergillus parasiticus. The toxins cause devastating economic losses because of strict regulations on distribution of contaminated products. Aspergillus sojae are...

  1. Gene expression profiling and identification of resistance genes to Aspergillus flavus infection in peanut through EST and microarray strategies.

    Science.gov (United States)

    Guo, Baozhu; Fedorova, Natalie D; Chen, Xiaoping; Wan, Chun-Hua; Wang, Wei; Nierman, William C; Bhatnagar, Deepak; Yu, Jiujiang

    2011-07-01

    Aspergillus flavus and A. parasiticus infect peanut seeds and produce aflatoxins, which are associated with various diseases in domestic animals and humans throughout the world. The most cost-effective strategy to minimize aflatoxin contamination involves the development of peanut cultivars that are resistant to fungal infection and/or aflatoxin production. To identify peanut Aspergillus-interactive and peanut Aspergillus-resistance genes, we carried out a large scale peanut Expressed Sequence Tag (EST) project which we used to construct a peanut glass slide oligonucleotide microarray. The fabricated microarray represents over 40% of the protein coding genes in the peanut genome. For expression profiling, resistant and susceptible peanut cultivars were infected with a mixture of Aspergillusflavus and parasiticus spores. The subsequent microarray analysis identified 62 genes in resistant cultivars that were up-expressed in response to Aspergillus infection. In addition, we identified 22 putative Aspergillus-resistance genes that were constitutively up-expressed in the resistant cultivar in comparison to the susceptible cultivar. Some of these genes were homologous to peanut, corn, and soybean genes that were previously shown to confer resistance to fungal infection. This study is a first step towards a comprehensive genome-scale platform for developing Aspergillus-resistant peanut cultivars through targeted marker-assisted breeding and genetic engineering. PMID:22069737

  2. The Volatome of Aspergillus fumigatus

    OpenAIRE

    Heddergott, C.; Calvo, A. M.; Latgé, J P

    2014-01-01

    Early detection of invasive aspergillosis is absolutely required for efficient therapy of this fungal infection. The identification of fungal volatiles in patient breath can be an alternative for the detection of Aspergillus fumigatus that still remains problematic. In this work, we investigated the production of volatile organic compounds (VOCs) by A. fumigatus in vitro, and we show that volatile production depends on the nutritional environment. A. fumigatus produces a multiplicity of VO...

  3. Two metabolites from Aspergillus flavipes.

    Science.gov (United States)

    Clark, A M; Hufford, C D; Robertson, L W

    1977-01-01

    Two novel fungal metabolites, N-benzoyl-L-phenylalaninol (1a) and asperphenamate (2) were isolated from the culture filtrate and mycelium of Aspergillus flavipes ATCC 11013. N-benzoyl-L-phenylalaninol was identified by direct comparison with an authentic sample. The structure of asperphenamate is proposed as (S)-N-benzoyl-phenylalanine-(S)-2-benzamido-3-phenyl propyl ester, based on chemical and spectroscopic evidence. PMID:875642

  4. Germination of Aspergillus niger conidia

    OpenAIRE

    Hayer, Kimran

    2014-01-01

    Aspergillus niger is a black-spored filamentous fungus that forms asexual spores called conidospores (‘conidia’). Germination of conidia, leading to the formation of hyphae, is initiated by conidial swelling and mobilisation of endogenous carbon and energy stores, followed by polarisation and emergence of a hyphal germ tube. These morphological and biochemical changes which define the model of germination have been studied with the aim of understanding how conidia sense and utilise different...

  5. Palmitoylation of the Cysteine Residue in the DHHC Motif of a Palmitoyl Transferase Mediates Ca2+ Homeostasis in Aspergillus.

    Directory of Open Access Journals (Sweden)

    Yuanwei Zhang

    2016-04-01

    Full Text Available Finely tuned changes in cytosolic free calcium ([Ca2+]c mediate numerous intracellular functions resulting in the activation or inactivation of a series of target proteins. Palmitoylation is a reversible post-translational modification involved in membrane protein trafficking between membranes and in their functional modulation. However, studies on the relationship between palmitoylation and calcium signaling have been limited. Here, we demonstrate that the yeast palmitoyl transferase ScAkr1p homolog, AkrA in Aspergillus nidulans, regulates [Ca2+]c homeostasis. Deletion of akrA showed marked defects in hyphal growth and conidiation under low calcium conditions which were similar to the effects of deleting components of the high-affinity calcium uptake system (HACS. The [Ca2+]c dynamics in living cells expressing the calcium reporter aequorin in different akrA mutant backgrounds were defective in their [Ca2+]c responses to high extracellular Ca2+ stress or drugs that cause ER or plasma membrane stress. All of these effects on the [Ca2+]c responses mediated by AkrA were closely associated with the cysteine residue of the AkrA DHHC motif, which is required for palmitoylation by AkrA. Using the acyl-biotin exchange chemistry assay combined with proteomic mass spectrometry, we identified protein substrates palmitoylated by AkrA including two new putative P-type ATPases (Pmc1 and Spf1 homologs, a putative proton V-type proton ATPase (Vma5 homolog and three putative proteins in A. nidulans, the transcripts of which have previously been shown to be induced by extracellular calcium stress in a CrzA-dependent manner. Thus, our findings provide strong evidence that the AkrA protein regulates [Ca2+]c homeostasis by palmitoylating these protein candidates and give new insights the role of palmitoylation in the regulation of calcium-mediated responses to extracellular, ER or plasma membrane stress.

  6. High abundance of Serine/Threonine-rich regions predicted to be hyper-O-glycosylated in the secretory proteins coded by eight fungal genomes

    Directory of Open Access Journals (Sweden)

    González Mario

    2012-09-01

    Full Text Available Abstract Background O-glycosylation of secretory proteins has been found to be an important factor in fungal biology and virulence. It consists in the addition of short glycosidic chains to Ser or Thr residues in the protein backbone via O-glycosidic bonds. Secretory proteins in fungi frequently display Ser/Thr rich regions that could be sites of extensive O-glycosylation. We have analyzed in silico the complete sets of putatively secretory proteins coded by eight fungal genomes (Botrytis cinerea, Magnaporthe grisea, Sclerotinia sclerotiorum, Ustilago maydis, Aspergillus nidulans, Neurospora crassa, Trichoderma reesei, and Saccharomyces cerevisiae in search of Ser/Thr-rich regions as well as regions predicted to be highly O-glycosylated by NetOGlyc (http://www.cbs.dtu.dk. Results By comparison with experimental data, NetOGlyc was found to overestimate the number of O-glycosylation sites in fungi by a factor of 1.5, but to be quite reliable in the prediction of highly O-glycosylated regions. About half of secretory proteins have at least one Ser/Thr-rich region, with a Ser/Thr content of at least 40% over an average length of 40 amino acids. Most secretory proteins in filamentous fungi were predicted to be O-glycosylated, sometimes in dozens or even hundreds of sites. Residues predicted to be O-glycosylated have a tendency to be grouped together forming hyper-O-glycosylated regions of varying length. Conclusions About one fourth of secretory fungal proteins were predicted to have at least one hyper-O-glycosylated region, which consists of 45 amino acids on average and displays at least one O-glycosylated Ser or Thr every four residues. These putative highly O-glycosylated regions can be found anywhere along the proteins but have a slight tendency to be at either one of the two ends.

  7. Ecophysiological characterization of Aspergillus carbonarius, Aspergillus tubingensis and Aspergillus niger isolated from grapes in Spanish vineyards.

    Science.gov (United States)

    García-Cela, E; Crespo-Sempere, A; Ramos, A J; Sanchis, V; Marin, S

    2014-03-01

    The aim of this study was to evaluate the diversity of black aspergilli isolated from berries from different agroclimatic regions of Spain. Growth characterization (in terms of temperature and water activity requirements) of Aspergillus carbonarius, Aspergillus tubingensis and Aspergillus niger was carried out on synthetic grape medium. A. tubingensis and A. niger showed higher maximum temperatures for growth (>45 °C versus 40-42 °C), and lower minimum aw requirements (0.83 aw versus 0.87 aw) than A. carbonarius. No differences in growth boundaries due to their geographical origin were found within A. niger aggregate isolates. Conversely, A. carbonarius isolates from the hotter and drier region grew and produced OTA at lower aw than other isolates. However, little genetic diversity in A. carbonarius was observed for the microsatellites tested and the same sequence of β-tubulin gene was observed; therefore intraspecific variability did not correlate with the geographical origin of the isolates or with their ability to produce OTA. Climatic change prediction points to drier and hotter climatic scenarios where A. tubingensis and A. niger could be even more prevalent over A. carbonarius, since they are better adapted to extreme high temperature and drier conditions.

  8. Identification of a classical mutant in the industrial host Aspergillus niger by systems genetics: LaeA is required for citric acid production and regulates the formation of some secondary metabolites

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jing; Arentshorst, Mark; Nair, Deepa; Dai, Ziyu; Baker, Scott E.; Frisvad, Jens; Nielsen, Kristian F.; Punt, Peter J.; Ram, Arthur F.

    2016-01-11

    Rapid acidification of the culture medium by the production of organic acids and the production of acid-induced proteases are key characteristics of the filamentous fungus Aspergillus niger. The D15 mutant of A. niger is non-acidifying mutant and used often for the expression of recombinant proteins in A. niger, because of its reduced production of extracellular proteases under non-acidic conditions. In this study, the D15 mutant is characterized in detail. Strongly reduced levels of citric and oxalic acid were observed in the D15 mutant both in shake flask cultures and in controlled batch cultivations. To identify the mutation in the D15 mutant, we successfully combined high-throughput sequencing (Illumina) with bulk segregant analysis. Because of the lack of a sexual cycle for A. niger, the parasexual cycle was used to generate a pool of segregants. From the 52 single nucleotide polymorphisms (SNPs) between the parental strains, three SNPs were homozygous in the genomic DNA of pool of segregants. These three SNPs mapped to all the right arm of chromosome II, indicating that this region contains the genetic locus affecting the phenotype related to acid production. Of the three SNPs, one mutation resulted in a missense mutation in the gene encoding the A. niger homologue of the A. nidulans methyltransferase gene laeA. Complementation analysis of the original mutant with the laeA gene and targeted disruption of laeA further confirmed that LaeA is involved in citric acid production in A. niger lab (N402) and citric acid production strains (ATCC 11414). Analysis of the secondary metabolite (SM) profile of the laeA mutants indicate that LaeA is required for the production of several SMs (asperrubrol, atromentin and JBIR86), but deletion of laeA also resulted in the presence of SMs (aspernigrin A/B and BMS-192548) that were not detected in the wild-type strain. The levels of ten other SMs were not strongly affected as a result of laeA deletion indicating that only a

  9. Identification of Two Different 14-α Sterol Demethylase-Related Genes (cyp51A and cyp51B) in Aspergillus fumigatus and Other Aspergillus Species

    OpenAIRE

    Mellado, E.; Diaz-Guerra, T. M.; Cuenca-Estrella, M.; Rodriguez-Tudela, J. L.

    2001-01-01

    Two cyp51-related genes (cyp51A and cyp51B) encoding 14-α sterol demethylase-like enzymes were identified in the opportunistic human pathogen Aspergillus fumigatus. PCR amplification using degenerate oligonucleotides based on conserved areas of cytochrome P450 demethylases of other filamentous fungi and yeasts allowed the cloning and sequencing of two different homologue genes in A. fumigatus. Southern analysis confirmed that both genes hybridized to distinct genomic loci and that both are re...

  10. Pulmonary hyalinizing granuloma associated with Aspergillus infection.

    Science.gov (United States)

    Pinckard, J Keith; Rosenbluth, Daniel B; Patel, Kishor; Dehner, Louis P; Pfeifer, John D

    2003-01-01

    A 38-year-old immunocompetent man with occupational exposure to Aspergillus presented with dyspnea, pleuritic chest pain, and hemoptysis. Chest roentgenograms and computed tomography scans demonstrated multiple pulmonary nodules bilaterally. An initial set of bronchial washing cultures grew Aspergillus fumigatus, serologic testing showed an elevated anti-Aspergillus titer, and immunodiffusion testing was positive for antibody against A. fumigatus and A. niger. There was no microbiologic or serologic evidence of infection by other pathogens, and no clinical or laboratory evidence of autoimmune disease. An open lung biopsy was diagnostic of pulmonary hyalinizing granuloma. This novel association with Aspergillus infection not only expands the spectrum of pathogens linked to pulmonary hyalinizing granuloma but also documents a new pattern of lung disease that can be caused by Aspergillus. PMID:12598920

  11. New taxa in Aspergillus section Usti

    DEFF Research Database (Denmark)

    Samson, R. A.; Varga, J.; Meijer, M.;

    2011-01-01

    Based on phylogenetic analysis of sequence data, Aspergillus section Usti includes 21 species, inducing two teleomorphic species Aspergillus heterothallicus (=Emericella heterothallica) and Fennellia monodii. Aspergillus germanicus sp. nov. was isolated from indoor air in Germany. This species has...... identical ITS sequences with A. insuetus CBS 119.27, but is clearly distinct from that species based on beta-tubulin and calmodulin sequence data. This species is unable to grow at 37 degrees C, similarly to A. keveii and A. insuetus. Aspergillus carlsbadensis sp. nov. was isolated from the Carlsbad Caverns...... National Park in New Mexico. This taxon is related to, but distinct from a dade including A. calidoustus, A. pseudodeflectus, A. insuetus and A. keveii on all trees. This species is also unable to grow at 37 degrees C, and acid production was not observed on CREA. Aspergillus californicus sp. nov...

  12. Aspergillus Osteomyelitis of the Skull.

    Science.gov (United States)

    Nicholson, Simon; King, Richard; Chumas, Paul; Russell, John; Liddington, Mark

    2016-07-01

    Osteomyelitis of the craniofacial skeleton is rare, with fungal pathogens least commonly implicated. The authors present 2 patients of osteomyelitis of the skull caused by Aspergillus spp. and discuss the diagnosis, clinicopathological course, and management strategies.Late recurrence seen in this type of infection warrants long-term follow-up and a high index of suspicion for the clinical signs associated with recurrence.Such patients would benefit from their surgical debridement being planned and managed via a specialist craniofacial unit, so as to utilize the most aesthetically sensitive approach and the experience of specialists from several surgical disciplines. PMID:27391523

  13. Ribonuclease Production by Aspergillus species

    OpenAIRE

    Eleni Gomes; Roberto da Silva; Alcides Serzedello

    1998-01-01

    Ribonuclease production by Aspergillus flavipes, A. sulphureus and A. fischeri in semi-synthetic medium, after 24-144 hours at 30ºC under shaking, was studied. After cultivation, the medium was separated from micelia by filtration and the resultant solution was used as enzymatic extract. The highest amount of biomass and RNase was obtained after 96 hours of cultivation. The enzymes produced by three species presented similar characteristics, with optimum temperature at 55ºC and two peaks of a...

  14. Conidial Hydrophobins of Aspergillus fumigatus

    OpenAIRE

    Paris, Sophie; Debeaupuis, Jean-Paul; Crameri, Reto; Carey, Marilyn; Charlès, Franck; Prévost, Marie Christine; Schmitt, Christine; Philippe, Bruno; Latgé, Jean Paul

    2003-01-01

    The surface of Aspergillus fumigatus conidia, the first structure recognized by the host immune system, is covered by rodlets. We report that this outer cell wall layer contains two hydrophobins, RodAp and RodBp, which are found as highly insoluble complexes. The RODA gene was previously characterized, and ΔrodA conidia do not display a rodlet layer (N. Thau, M. Monod, B. Crestani, C. Rolland, G. Tronchin, J. P. Latgé, and S. Paris, Infect. Immun. 62:4380-4388, 1994). The RODB gene was cloned...

  15. Two novel species of Aspergillus section Nigri from indoor air

    Science.gov (United States)

    Aspergillus collinsii, Aspergillus floridensis, and Aspergillus trinidadensis are described as novel uniseriate species of Aspergillus section Nigri isolated from air samples. To describe the species we used phenotypes from 7-d Czapek yeast extract agar culture (CYA) and malt extract agar culture (M...

  16. Secondary metabolite profiles and antifungal drug susceptibility of Aspergillus fumigatus and closely related species, Aspergillus lentulus, Aspergillus udagawae, and Aspergillus viridinutans.

    Science.gov (United States)

    Tamiya, Hiroyuki; Ochiai, Eri; Kikuchi, Kazuyo; Yahiro, Maki; Toyotome, Takahito; Watanabe, Akira; Yaguchi, Takashi; Kamei, Katsuhiko

    2015-05-01

    The incidence of Aspergillus infection has been increasing in the past few years. Also, new Aspergillus fumigatus-related species, namely Aspergillus lentulus, Aspergillus udagawae, and Aspergillus viridinutans, were shown to infect humans. These fungi exhibit marked morphological similarities to A. fumigatus, albeit with different clinical courses and antifungal drug susceptibilities. The present study used liquid chromatography/time-of-flight mass spectrometry to identify the secondary metabolites secreted as virulence factors by these Aspergillus species and compared their antifungal susceptibility. The metabolite profiles varied widely among A. fumigatus, A. lentulus, A. udagawae, and A. viridinutans, producing 27, 13, 8, and 11 substances, respectively. Among the mycotoxins, fumifungin, fumiquinazoline A/B and D, fumitremorgin B, gliotoxin, sphingofungins, pseurotins, and verruculogen were only found in A. fumigatus, whereas auranthine was only found in A. lentulus. The amount of gliotoxin, one of the most abundant mycotoxins in A. fumigatus, was negligible in these related species. In addition, they had decreased susceptibility to antifungal agents such as itraconazole and voriconazole, even though metabolites that were shared in the isolates showing higher minimum inhibitory concentrations than epidemiological cutoff values were not detected. These strikingly different secondary metabolite profiles may lead to the development of more discriminative identification protocols for such closely related Aspergillus species as well as improved treatment outcomes.

  17. Diversity of Aspergillus oryzae genotypes (RFLP) isolated from traditional soy sauce production within Malaysia and Southeast Asia

    Science.gov (United States)

    DNA fingerprinting was performed on 64 strains of Aspergillus oryzae and one strain of A. sojae isolated from soysauce factories within Malaysia and Southeast Asia that use primitive traditional methods in producing 'tamari type' Cantonese soy sauce. PstI digests of total genomic DNA from each isol...

  18. Two novel, putatively cell wall-associated and glycosylphosphatidylinositol-anchored alpha-glucanotransferase enzymes of aspergillus niger

    NARCIS (Netherlands)

    van der Kaaij, R. A.; Yuan, X.-L.; Franken, A.; Ram, A. F. J.; Punt, P. J.; Dijkhuizen, L.; Maarel, M.J.E.C. van der

    2007-01-01

    In the genome sequence of Aspergillus niger CBS 513.88, three genes were identified with high similarity to fungal alpha-amylases. The protein sequences derived from these genes were different in two ways from all described fungal alpha-amylases: they were predicted to be glycosylphosphatidyllinosit

  19. Two novel, putatively cell wall-associated and glycosylphosphatidylinositol-anchored α-glucanotransferase enzymes of Aspergillus niger

    NARCIS (Netherlands)

    Kaaij, R.M. van der; Yuan, X.L.; Franken, A.; Ram, A.F.J.; Punt, P.J.; Maarel, M.J.E.C. van der; Dijkhuizen, L.

    2007-01-01

    In the genome sequence of Aspergillus niger CBS 513.88, three genes were identified with high similarity to fungal α-amylases. The protein sequences derived from these genes were different in two ways from all described fungal α-amylases: they were predicted to be glycosylphosphatidylinositol anchor

  20. Biochemical characterization of Aspergillus niger Cfcl, a glycoside hydrolase family 18 chitinase that releases monomers during substrate hydrolysis

    NARCIS (Netherlands)

    van Munster, Jolanda M.; van der Kaaij, Rachel M.; Dijkhuizen, Lubbert; van der Maarel, Marc J. E. C.

    2012-01-01

    The genome of the industrially important fungus Aspergillus niger encodes a large number of glycoside hydrolase family 18 members annotated as chitinases. We identified one of these putative chitinases, Cfcl, as a representative of a distinct phylogenetic clade of homologous enzymes conserved in all

  1. Genetic diversity of Aspergillus species isolated from onychomycosis and Aspergillus hongkongensis sp. nov., with implications to antifungal susceptibility testing.

    Science.gov (United States)

    Tsang, Chi-Ching; Hui, Teresa W S; Lee, Kim-Chung; Chen, Jonathan H K; Ngan, Antonio H Y; Tam, Emily W T; Chan, Jasper F W; Wu, Andrea L; Cheung, Mei; Tse, Brian P H; Wu, Alan K L; Lai, Christopher K C; Tsang, Dominic N C; Que, Tak-Lun; Lam, Ching-Wan; Yuen, Kwok-Yung; Lau, Susanna K P; Woo, Patrick C Y

    2016-02-01

    Thirteen Aspergillus isolates recovered from nails of 13 patients (fingernails, n=2; toenails, n=11) with onychomycosis were characterized. Twelve strains were identified by multilocus sequencing as Aspergillus spp. (Aspergillus sydowii [n=4], Aspergillus welwitschiae [n=3], Aspergillus terreus [n=2], Aspergillus flavus [n=1], Aspergillus tubingensis [n=1], and Aspergillus unguis [n=1]). Isolates of A. terreus, A. flavus, and A. unguis were also identifiable by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The 13th isolate (HKU49(T)) possessed unique morphological characteristics different from other Aspergillus spp. Molecular characterization also unambiguously showed that HKU49(T) was distinct from other Aspergillus spp. We propose the novel species Aspergillus hongkongensis to describe this previously unknown fungus. Antifungal susceptibility testing showed most Aspergillus isolates had low MICs against itraconazole and voriconazole, but all Aspergillus isolates had high MICs against fluconazole. A diverse spectrum of Aspergillus species is associated with onychomycosis. Itraconazole and voriconazole are probably better drug options for Aspergillus onychomycosis.

  2. Characterization of the Far Transcription Factor Family in Aspergillus flavus

    Science.gov (United States)

    Luo, Xingyu; Affeldt, Katharyn J.; Keller, Nancy P.

    2016-01-01

    Metabolism of fatty acids is a critical requirement for the pathogenesis of oil seed pathogens including the fungus Aspergillus flavus. Previous studies have correlated decreased ability to grow on fatty acids with reduced virulence of this fungus on host seed. Two fatty acid metabolism regulatory transcription factors, FarA and FarB, have been described in other filamentous fungi. Unexpectedly, we find A. flavus possesses three Far homologs, FarA, FarB, and FarC, with FarA and FarC showing a greater protein similarity to each other than FarB. farA and farB are located in regions of colinearity in all Aspergillus spp. sequenced to date, whereas farC is limited to a subset of species where it is inserted in an otherwise colinear region in Aspergillus genomes. Deletion and overexpression (OE) of farA and farB, but not farC, yielded mutants with aberrant growth patterns on specific fatty acids as well as altered expression of genes involved in fatty acid metabolism. Marked differences included significant growth defects of both ∆farA and ∆farB on medium-chain fatty acids and decreased growth of OE::farA on unsaturated fatty acids. Loss of farA diminished expression of mitochondrial β-oxidation genes whereas OE::farA inhibited expression of genes involved in unsaturated fatty acid catabolism. FarA also positively regulated the desaturase genes required to generate polyunsaturated fatty acids. Aflatoxin production on toxin-inducing media was significantly decreased in the ∆farB mutant and increased in the OE::farB mutant, with gene expression data supporting a role for FarB in tying β-oxidation processes with aflatoxin accumulation. PMID:27534569

  3. Integrated database for identifying candidate genes for Aspergillus flavus resistance in maize

    OpenAIRE

    Pechan Tibor; Peethambaran Bela; Pechanova Olga; Hawkins Leigh K; Warburton Marilyn L; Bridges Susan M; Harper Jonathan; Gresham Cathy; Kelley Rowena Y; Luthe Dawn S; Mylroie J E; Ankala Arunkanth; Ozkan Seval; Henry W B; Williams W P

    2010-01-01

    Abstract Background Aspergillus flavus Link:Fr, an opportunistic fungus that produces aflatoxin, is pathogenic to maize and other oilseed crops. Aflatoxin is a potent carcinogen, and its presence markedly reduces the value of grain. Understanding and enhancing host resistance to A. flavus infection and/or subsequent aflatoxin accumulation is generally considered an efficient means of reducing grain losses to aflatoxin. Different proteomic, genomic and genetic studies of maize (Zea mays L.) ha...

  4. Comparative chemistry of Aspergillus oryzae (RIB40) and A. flavus (NRRL 3357)

    DEFF Research Database (Denmark)

    Rank, Christian; Klejnstrup, Marie Louise; Petersen, Lene Maj;

    2012-01-01

    Aspergillus oryzae and A. flavus are important species in industrial biotechnology and food safety and have been some of the first aspergilli to be fully genome sequenced. Bioinformatic analysis has revealed 99.5% gene homology between the two species pointing towards a large coherence in the sec...... alkaloids related to the A. flavus metabolites ditryptophenalines and miyakamides. Generally the secondary metabolite capability of A. oryzae presents several novel end products likely to result from the domestication process from A. flavus....

  5. Metabolites from marine fungus Aspergillus sp.

    Digital Repository Service at National Institute of Oceanography (India)

    Wahidullah, S.; Rajmanickam, R.; DeSouza, L.

    Chemical examination of a methanolic extract of the marine fungus, Aspergillus sp., isolated from marine grass environment, yielded a steroid, ergosterol peroxide (1), and a mixture of known glyceride esters (2,3) of unsaturated fatty acids...

  6. Putative virulence factors of Aspergillus fumigatus

    NARCIS (Netherlands)

    Tomee, JFC; Kauffman, HF

    2000-01-01

    Various putative virulence factors of Aspergillus fumigatus have been studied over the past decades. A. fumigatus gliotoxin is a potent inhibitor of the mucociliary system. Several fungal metabolites interfere with phagocytosis and opsonization including toxins, 'conidial inhibitory factor', 'A. fum

  7. New species in Aspergillus section Terrei

    DEFF Research Database (Denmark)

    Samson, R. A.; Peterson, S. W.; Frisvad, Jens Christian;

    2011-01-01

    Section Terrei of Aspergillus was studied using a polyphasic approach including sequence analysis of parts of the beta-tubulin and calmodulin genes and the ITS region, macro- and micromorphological analyses and examination of extrolite profiles to describe three new species in this section. Based...... on phylogenetic analysis of calmodulin and beta-tubulin sequences seven lineages were observed among isolates that have previously been treated as A. terreus and its subspecies by Raper & Fennell (1965) and others. Aspergillus alabamensis, A. terreus var. floccosus, A. terreus var. africanus, A. terreus var....... floccosus, A. terreus var. africanus, A. terreus var. aureus, while Aspergillus hortai is recognised at species level. Aspergillus terreus NRRL 4017 is described as the new species A. pseudoterreus. Also included in section Terrei are some species formerly placed in sections Flavipedes and Versicolores. A...

  8. [Aspergillus infection and chronic septic granulomatosis].

    Science.gov (United States)

    Mouy, R; Bremard, C; Fischer, A; Huu Trong, P; Vilmer, E; Griscelli, C

    1985-12-01

    Chronic granulomatous disease of childhood is a hereditary abnormality of phagocytic cells, frequently associated with Aspergillus infections. From 1969 to 1984, 14 of 37 children with chronic granulomatous disease have presented with pulmonary (13 cases) and/or osteo-articular (1 case) aspergillosis. The paucity of symptoms was a characteristic of these infections. Lung lesions extending to the thoracic chest wall carried the bad prognosis. Neither the Aspergillus skin test nor the Aspergillus serology could definitely confirm the diagnosis. Only broncho-alveolar lavage and biopsy with isolation of Aspergillus could confirm the diagnosis. Long-term therapy with amphotericin B alone or associated with other antifungal agents is necessary. For the past 3 years, ketoconazole prophylaxis has been used in 23 children and none of these children has developed aspergillosis.

  9. Three new species of Aspergillus section Flavi isolated from almonds and maize in Portugal

    Science.gov (United States)

    Three new aflatoxin-producing species belonging to Aspergillus section Flavi are described, Aspergillus mottae, Aspergillus sergii and Aspergillus transmontanensis. These species were isolated from Portuguese almonds and maize. An investigation examining morphology, extrolites and molecular data was...

  10. Polyketides in Aspergillus terreus: biosynthesis pathway discovery and application.

    Science.gov (United States)

    Yin, Ying; Cai, Menghao; Zhou, Xiangshan; Li, Zhiyong; Zhang, Yuanxing

    2016-09-01

    The knowledge of biosynthesis gene clusters, production improving methods, and bioactivity mechanisms is very important for the development of filamentous fungi metabolites. Metabolic engineering and heterologous expression methods can be applied to improve desired metabolite production, when their biosynthesis pathways have been revealed. And, stable supplement is a necessary basis of bioactivity mechanism discovery and following clinical trial. Aspergillus terreus is an outstanding producer of many bioactive agents, and a large part of them are polyketides. In this review, we took polyketides from A. terreus as examples, focusing on 13 polyketide synthase (PKS) genes in A. terreus NIH 2624 genome. The biosynthesis pathways of nine PKS genes have been reported, and their downstream metabolites are lovastatin, terreic acid, terrein, geodin, terretonin, citreoviridin, and asperfuranone, respectively. Among them, lovastatin is a well-known hypolipidemic agent. Terreic acid, terrein, citreoviridin, and asperfuranone show good bioactivities, especially anticancer activities. On the other hand, geodin and terretonin are mycotoxins. So, biosynthesis gene cluster information is important for the production or elimination of them. We also predicted three possible gene clusters that contain four PKS genes by homologous gene alignment with other Aspergillus strains. We think that this is an effective way to mine secondary metabolic gene clusters. PMID:27455860

  11. The histone acetyltransferase GcnE (GCN5) plays a central role in the regulation of Aspergillus asexual development.

    Science.gov (United States)

    Cánovas, David; Marcos, Ana T; Gacek, Agnieszka; Ramos, María S; Gutiérrez, Gabriel; Reyes-Domínguez, Yazmid; Strauss, Joseph

    2014-08-01

    Acetylation of histones is a key regulatory mechanism of gene expression in eukaryotes. GcnE is an acetyltransferase of Aspergillus nidulans involved in the acetylation of histone H3 at lysine 9 and lysine 14. Previous works have demonstrated that deletion of gcnE results in defects in primary and secondary metabolism. Here we unveil the role of GcnE in development and show that a ∆gcnE mutant strain has minor growth defects but is impaired in normal conidiophore development. No signs of conidiation were found after 3 days of incubation, and immature and aberrant conidiophores were found after 1 week of incubation. Centroid linkage clustering and principal component (PC) analysis of transcriptomic data suggest that GcnE occupies a central position in Aspergillus developmental regulation and that it is essential for inducing conidiation genes. GcnE function was found to be required for the acetylation of histone H3K9/K14 at the promoter of the master regulator of conidiation, brlA, as well as at the promoters of the upstream developmental regulators of conidiation flbA, flbB, flbC, and flbD (fluffy genes). However, analysis of the gene expression of brlA and the fluffy genes revealed that the lack of conidiation originated in a complete absence of brlA expression in the ∆gcnE strain. Ectopic induction of brlA from a heterologous alcA promoter did not remediate the conidiation defects in the ∆gcnE strain, suggesting that additional GcnE-mediated mechanisms must operate. Therefore, we conclude that GcnE is the only nonessential histone modifier with a strong role in fungal development found so far.

  12. Data on the presence or absence of genes encoding essential proteins for ochratoxin and fumonisin biosynthesis in Aspergillus niger and Aspergillus welwitschiae

    Science.gov (United States)

    Massi, Fernanda Pelisson; Sartori, Daniele; Ferranti, Larissa de Souza; Iamanaka, Beatriz Thie; Taniwaki, Marta Hiromi; Vieira, Maria Lucia Carneiro; Fungaro, Maria Helena Pelegrinelli

    2016-01-01

    We present the multiplex PCR data for the presence/absence of genes involved in OTA and FB2 biosynthesis in Aspergillus niger/Aspergillus welwitschiae strains isolated from different food substrates in Brazil. Among the 175 strains analyzed, four mPCR profiles were found: Profile 1 (17%) highlights strains harboring in their genome the pks, radH and the fum8 genes. Profile 2 (3.5%) highlights strains harboring genes involved in OTA biosynthesis i.e. radH and pks. Profile 3 (51.5%) highlights strains harboring the fum8 gene. Profile 4 (28%) highlights strains not carrying the genes studied herein. This research content is supplemental to our original research article, “Prospecting for the incidence of genes involved in ochratoxin and fumonisin biosynthesis in Brazilian strains of A. niger and A. welwitschiae” [1]. PMID:27054181

  13. Effect of carbon and nitrogen assimilation on chlorophyll fluorescence emission by the cyanobacterium Anacystis nidulans

    Energy Technology Data Exchange (ETDEWEB)

    Romero, J.M.; Lara, C. (Instituto de Bioquimica Vegetal y Fotosintesis, Univ. de Sevilla y CSIC, Sevilla (ES)); Sivak, M.N. (Dept. of Biochemistry, Michigan State Univ., East Lansing (US))

    1992-01-01

    O{sub 2} evolution and chlorophyll A fluorescence emission have been monitored in intact cells of the cyanobacterium Anacystis nidulans 1402-1 to study the influence of carbon and nitrogen assimilation on the operation of the photosynthetic apparatus. The pattern of fluorescence induction in dark-adapted cyanobacterial cells was different from that of higher plants. Cyanobacteria undergo large, rapid state transitions upon illumination, which lead to marked changes in the fluorescence yield, complicating the estimation of quenching coefficients. The Kautsky effect was not evident, although it could be masked by a state II-state I transition, upon illumination with actinic light. The use of inhibitors of carbon assimilation such as D,L-glyceraldehyde or iodoacetamide allowed us to relate changes in variable fluorescence to active CO{sub 2} fixation. Ammonium, but not nitrate, induced non-photochemical fluorescence quenching, in agreement with a previous report on green algae, indicative of an ammonium-induced state i transition. (au).

  14. Effects of long-wavelength ultraviolet (UV-A) radiation on the growth of Anacystis Nidulans

    International Nuclear Information System (INIS)

    The growth of Anacystis nidulans cells which had been grown under visible light only (>390 nm) was suppressed by long-wavelength ultraviolet (UV-A, 320-390 nm) radiation. The growth resumed after 24 h. Cells grown under UV-A supplemented light contained less chlorophyll and phycocyanin and more carotenoid than control cells. The finding that UV-A radiation inhibited the rate of delta-aminolevulinic acid synthesis indicated that the decreases in the photosynthetic pigments were mainly due to the inhibition of their biosynthesis rather than to photodestruction of pigments by UV-A radiation. The primary cause of the inhibitory effects seems to be the inhibition of the photosynthetic process which can be measured as the rho-benzoquinone Hill reaction. Previous exposure to UV-A radiation conferred some resistance on the cells to this inhibitory radiation. Thus UV-A radiation itself may activate a system that repairs damage caused by UV-A radiation and/or protects against the radiation. (author)

  15. Clustered array of ochratoxin A biosynthetic genes in Aspergillus steynii and their expression patterns in permissive conditions.

    Science.gov (United States)

    Gil-Serna, Jessica; Vázquez, Covadonga; González-Jaén, María Teresa; Patiño, Belén

    2015-12-01

    Aspergillus steynii is probably the most relevant species of section Circumdati producing ochratoxin A (OTA). This mycotoxin contaminates a wide number of commodities and it is highly toxic for humans and animals. Little is known on the biosynthetic genes and their regulation in Aspergillus species. In this work, we identified and analysed three contiguous genes in A. steynii using 5'-RACE and genome walking approaches which predicted a cytochrome P450 monooxygenase (p450ste), a non-ribosomal peptide synthetase (nrpsste) and a polyketide synthase (pksste). These three genes were contiguous within a 20742 bp long genomic DNA fragment. Their corresponding cDNA were sequenced and their expression was analysed in three A. steynii strains using real time RT-PCR specific assays in permissive conditions in in vitro cultures. OTA was also analysed in these cultures. Comparative analyses of predicted genomic, cDNA and amino acid sequences were performed with sequences of similar gene functions. All the results obtained in these analyses were consistent and point out the involvement of these three genes in OTA biosynthesis by A. steynii and showed a co-ordinated expression pattern. This is the first time that a clustered organization OTA biosynthetic genes has been reported in Aspergillus genus. The results also suggested that this situation might be common in Aspergillus OTA-producing species and distinct to the one described for Penicillium species.

  16. Challenges in Whole-Genome Annotation of Pyrosequenced Eukaryotic Genomes

    Energy Technology Data Exchange (ETDEWEB)

    Kuo, Alan; Grigoriev, Igor

    2009-04-17

    Pyrosequencing technologies such as 454/Roche and Solexa/Illumina vastly lower the cost of nucleotide sequencing compared to the traditional Sanger method, and thus promise to greatly expand the number of sequenced eukaryotic genomes. However, the new technologies also bring new challenges such as shorter reads and new kinds and higher rates of sequencing errors, which complicate genome assembly and gene prediction. At JGI we are deploying 454 technology for the sequencing and assembly of ever-larger eukaryotic genomes. Here we describe our first whole-genome annotation of a purely 454-sequenced fungal genome that is larger than a yeast (>30 Mbp). The pezizomycotine (filamentous ascomycote) Aspergillus carbonarius belongs to the Aspergillus section Nigri species complex, members of which are significant as platforms for bioenergy and bioindustrial technology, as members of soil microbial communities and players in the global carbon cycle, and as agricultural toxigens. Application of a modified version of the standard JGI Annotation Pipeline has so far predicted ~;;10k genes. ~;;12percent of these preliminary annotations suffer a potential frameshift error, which is somewhat higher than the ~;;9percent rate in the Sanger-sequenced and conventionally assembled and annotated genome of fellow Aspergillus section Nigri member A. niger. Also,>90percent of A. niger genes have potential homologs in the A. carbonarius preliminary annotation. Weconclude, and with further annotation and comparative analysis expect to confirm, that 454 sequencing strategies provide a promising substrate for annotation of modestly sized eukaryotic genomes. We will also present results of annotation of a number of other pyrosequenced fungal genomes of bioenergy interest.

  17. Versatile Enzyme Expression and Characterization System for Aspergillus nidulans, with the Penicillium brevicompactum Polyketide Synthase Gene from the Mycophenolic Acid Gene Cluster as a Test Case

    DEFF Research Database (Denmark)

    Hansen, Bjarne Gram; Salomonsen, Bo; Nielsen, Morten Thrane;

    2011-01-01

    , protein variants can easily be made and expressed from the same locus, which is mandatory for proper comparative analyses. Lastly, all individual elements of the vectors can easily be substituted for other similar elements, ensuring the flexibility of the system. We have demonstrated the potential...

  18. Post-Synthetic Defucosylation of AGP by Aspergillus nidulans α-1,2-Fucosidase Expressed in Arabidopsis Apoplast Induces Compensatory Upregulation of α-1,2-Fucosyltransferases.

    Science.gov (United States)

    Pogorelko, Gennady V; Reem, Nathan T; Young, Zachary T; Chambers, Lauran; Zabotina, Olga A

    2016-01-01

    Cell walls are essential components of plant cells which perform a variety of important functions for the different cell types, tissues and organs of a plant. Besides mechanical function providing cell shape, cell walls participate in intercellular communication, defense during plant-microbe interactions, and plant growth. The plant cell wall consists predominantly of polysaccharides with the addition of structural glycoproteins, phenolic esters, minerals, lignin, and associated enzymes. Alterations in the cell wall composition created through either changes in biosynthesis of specific constituents or their post-synthetic modifications in the apoplast compromise cell wall integrity and frequently induce plant compensatory responses as a result of these alterations. Here we report that post-synthetic removal of fucose residues specifically from arabinogalactan proteins in the Arabidopsis plant cell wall induces differential expression of fucosyltransferases and leads to the root and hypocotyl elongation changes. These results demonstrate that the post-synthetic modification of cell wall components presents a valuable approach to investigate the potential signaling pathways induced during plant responses to such modifications that usually occur during plant development and stress responses. PMID:27448235

  19. Post-Synthetic Defucosylation of AGP by Aspergillus nidulans α-1,2-Fucosidase Expressed in Arabidopsis Apoplast Induces Compensatory Upregulation of α-1,2-Fucosyltransferases

    Science.gov (United States)

    Pogorelko, Gennady V.; Reem, Nathan T.; Young, Zachary T.; Chambers, Lauran; Zabotina, Olga A.

    2016-01-01

    Cell walls are essential components of plant cells which perform a variety of important functions for the different cell types, tissues and organs of a plant. Besides mechanical function providing cell shape, cell walls participate in intercellular communication, defense during plant-microbe interactions, and plant growth. The plant cell wall consists predominantly of polysaccharides with the addition of structural glycoproteins, phenolic esters, minerals, lignin, and associated enzymes. Alterations in the cell wall composition created through either changes in biosynthesis of specific constituents or their post-synthetic modifications in the apoplast compromise cell wall integrity and frequently induce plant compensatory responses as a result of these alterations. Here we report that post-synthetic removal of fucose residues specifically from arabinogalactan proteins in the Arabidopsis plant cell wall induces differential expression of fucosyltransferases and leads to the root and hypocotyl elongation changes. These results demonstrate that the post-synthetic modification of cell wall components presents a valuable approach to investigate the potential signaling pathways induced during plant responses to such modifications that usually occur during plant development and stress responses. PMID:27448235

  20. Enzymatic synthesis of β-xylosyl-oligosaccharides by transxylosylation using two beta-xylosidases of glycoside hydrolase family 3 from Aspergillus nidulans FGSC A4

    DEFF Research Database (Denmark)

    Dilokpimol, Adiphol; Nakai, Hiroyuki; Gotfredsen, Charlotte Held;

    2011-01-01

    alcohols as acceptors 18 different p-xylosyl-oligosaccharides were synthesised in 2-36% (BxlA) and 6-66% (BxlB) yields by transxylosylation. BxlA utilised the monosaccharides D-mannose, D-lyxose, D-talose, D-xylose, D-arabinose, L-fucose, D-glucose, D-galactose and D-fructose as acceptors, whereas Bxl......B used the same except for D-lyxose, D-arabinose and L-fucose. BxlB transxylosylated the disaccharides xylobiose, lactulose, sucrose, lactose and turanose in upto 35% yield, while BxlA gave inferior yields on these acceptors. The regioselectivity was acceptor dependent and primarily involved beta-1...

  1. Post-Synthetic Defucosylation of AGP by Aspergillus nidulans α-1,2-Fucosidase Expressed in Arabidopsis Apoplast Induces Compensatory Upregulation of α-1,2-Fucosyltransferases.

    Directory of Open Access Journals (Sweden)

    Gennady V Pogorelko

    Full Text Available Cell walls are essential components of plant cells which perform a variety of important functions for the different cell types, tissues and organs of a plant. Besides mechanical function providing cell shape, cell walls participate in intercellular communication, defense during plant-microbe interactions, and plant growth. The plant cell wall consists predominantly of polysaccharides with the addition of structural glycoproteins, phenolic esters, minerals, lignin, and associated enzymes. Alterations in the cell wall composition created through either changes in biosynthesis of specific constituents or their post-synthetic modifications in the apoplast compromise cell wall integrity and frequently induce plant compensatory responses as a result of these alterations. Here we report that post-synthetic removal of fucose residues specifically from arabinogalactan proteins in the Arabidopsis plant cell wall induces differential expression of fucosyltransferases and leads to the root and hypocotyl elongation changes. These results demonstrate that the post-synthetic modification of cell wall components presents a valuable approach to investigate the potential signaling pathways induced during plant responses to such modifications that usually occur during plant development and stress responses.

  2. Ribonuclease Production by Aspergillus species

    Directory of Open Access Journals (Sweden)

    Eleni Gomes

    1998-09-01

    Full Text Available Ribonuclease production by Aspergillus flavipes, A. sulphureus and A. fischeri in semi-synthetic medium, after 24-144 hours at 30ºC under shaking, was studied. After cultivation, the medium was separated from micelia by filtration and the resultant solution was used as enzymatic extract. The highest amount of biomass and RNase was obtained after 96 hours of cultivation. The enzymes produced by three species presented similar characteristics, with optimum temperature at 55ºC and two peaks of activity at pH 4.5 and 7.0. A. flavipes RNases were more sensitive to temperature: 50% of the initial activity was lost after 1 hour at 70ºC. After this heat treatment, RNase of A. sulphureus lost 30% of this activity and that of A. fischeri only 16%. The nucleotides released by enzimatic hydrolysis of RNA were separated by ion exchange chromatography in a AG-1X8-formiate column and identified by paper chromatography. This procedure indicated that the raw enzymatic extract of Aspergillus flavipes is able to hydrolyze RNA, releasing 3'-nucleotides monophosphate at pH 4.5 and 3' and 5'-nucleotides monophosphate at pH 7.0 and 8.5. This result suggests that this strain produces two different types of RNase, one acidic and other alcaline, with different specificities.A produção de ribonucleases extracelulares pelos fungos Aspergillus flavipes, A. sulphureus e A. fischeri foi estudada em meio semi-sintético por períodos de 24 a 144 horas, em "shaker" a 30ºC. Após o cultivo, o meio foi separado da massa micelial por filtração, sendo o filtrado utilizado como solução enzimática bruta. As três espécies produziram maior quantidade de biomassa e ribonuclease após 96 horas de cultivo. O estudo das RNases como extrato enzimático bruto demonstrou que existe grande similaridade entre as enzimas das três espécies, com temperaturas ótimas de 55ºC e dois picos de atividade a pH 4,5 e a pH 7,0. A RNAse produzida pelo fungo A. flavipes demonstrou ser mais

  3. Neuroimaging features of cerebral aspergillus abscess: Case report

    Directory of Open Access Journals (Sweden)

    Jie Bai

    2015-06-01

    Conclusion: Cerebral aspergillus abscesses possess some degree neuroimaging features on traditional CT/MR imaging. Combined with patient's clinical history, CT/MRI examination could facilitate early diagnosis of aspergillus abscesses in central nervous system.

  4. Comparison of species composition and fumonisin production in Aspergillus section Nigri populations in maize kernels from USA and Italy.

    Science.gov (United States)

    Susca, Antonia; Moretti, Antonio; Stea, Gaetano; Villani, Alessandra; Haidukowski, Miriam; Logrieco, Antonio; Munkvold, Gary

    2014-10-01

    non-producing strains distributed among the clades: A. welwitschiae, A. niger group 1 and A. niger group 2, confirming the potential of Aspergillus sect. Nigri species to contribute to total fumonisin contamination of maize. A higher percentage of A. niger isolates (72.0%) produced FB2 compared to A. welwitschiae (36.6%). The percentage of FB2-producing A. niger strains was similar in the USA and Italian populations; however, the predominance of A. niger in the USA population suggests a higher potential for fumonisin production. Some strains with fum8 present in the genome did not produce FB2in vitro, confirming the ineffectiveness of fum8 presence as a predictor of FB2 production.

  5. Doxycycline-regulated gene expression in the opportunistic fungal pathogen Aspergillus fumigatus

    Directory of Open Access Journals (Sweden)

    Askew David S

    2005-01-01

    Full Text Available Abstract Background Although Aspergillus fumigatus is an important human fungal pathogen there are few expression systems available to study the contribution of specific genes to the growth and virulence of this opportunistic mould. Regulatable promoter systems based upon prokaryotic regulatory elements in the E. coli tetracycline-resistance operon have been successfully used to manipulate gene expression in several organisms, including mice, flies, plants, and yeast. However, the system has not yet been adapted for Aspergillus spp. Results Here we describe the construction of plasmid vectors that can be used to regulate gene expression in A. fumigatus using a simple co-transfection approach. Vectors were generated in which the tetracycline transactivator (tTA or the reverse tetracycline transactivator (rtTA2s-M2 are controlled by the A. nidulans gpdA promoter. Dominant selectable cassettes were introduced into each plasmid, allowing for selection following gene transfer into A. fumigatus by incorporating phleomycin or hygromycin into the medium. To model an essential gene under tetracycline regulation, the E. coli hygromycin resistance gene, hph, was placed under the control of seven copies of the TetR binding site (tetO7 in a plasmid vector and co-transfected into A. fumigatus protoplasts together with one of the two transactivator plasmids. Since the hph gene is essential to A. fumigatus in the presence of hygromycin, resistance to hygromycin was used as a marker of hph reporter gene expression. Transformants were identified in which the expression of tTA conferred hygromycin resistance by activating expression of the tetO7-hph reporter gene, and the addition of doxycycline to the medium suppressed hygromycin resistance in a dose-dependent manner. Similarly, transformants were identified in which expression of rtTA2s-M2 conferred hygromycin resistance only in the presence of doxycycline. The levels of doxycycline required to regulate

  6. New promoters to improve heterologous protein production in Aspergillus vadensis

    NARCIS (Netherlands)

    Culleton, H.; Bouzid, O.; McKie, V.; de Vries, Ronald P.

    2014-01-01

    Aspergillus is a widely used host organism for the industrial production of homologous and heterologous proteins. Although Aspergillus niger is most commonly used, a close relative of this species, Aspergillus vadensis, has been suggested as a suitable and more favourable alternative due in part, to

  7. 21 CFR 866.3040 - Aspergillus spp. serological reagents.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Aspergillus spp. serological reagents. 866.3040... (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3040 Aspergillus spp. serological reagents. (a) Identification. Aspergillus spp. serological reagents are devices...

  8. Aspergillus luchuensis, an industrially important black Aspergillus in East Asia.

    Directory of Open Access Journals (Sweden)

    Seung-Beom Hong

    Full Text Available Aspergilli known as black- and white-koji molds which are used for awamori, shochu, makgeolli and other food and beverage fermentations, are reported in the literature as A. luchuensis, A. awamori, A. kawachii, or A. acidus. In order to elucidate the taxonomic position of these species, available ex-type cultures were compared based on morphology and molecular characters. A. luchuensis, A. kawachii and A. acidus showed the same banding patterns in RAPD, and the three species had the same rDNA-ITS, β-tubulin and calmodulin sequences and these differed from those of the closely related A. niger and A. tubingensis. Morphologically, the three species are not significantly different from each other or from A. niger and A. tubingensis. It is concluded that A. luchuensis, A. kawachii and A. acidus are the same species, and A. luchuensis is selected as the correct name based on priority. Strains of A. awamori which are stored in National Research Institute of Brewing in Japan, represent A. niger (n = 14 and A. luchuensis (n = 6. The neotype of A. awamori (CBS 557.65 =  NRRL 4948 does not originate from awamori fermentation and it is shown to be identical with the unknown taxon Aspergillus welwitschiae. Extrolite analysis of strains of A. luchuensis showed that they do not produce mycotoxins and therefore can be considered safe for food and beverage fermentations. A. luchuensis is also frequently isolated from meju and nuruk in Korea and Puerh tea in China and the species is probably common in the fermentation environment of East Asia. A re-description of A. luchuensis is provided because the incomplete data in the original literature.

  9. Combined molecular and biochemical approach identifies Aspergillus japonicus and Aspergillus aculeatus as two species

    DEFF Research Database (Denmark)

    Parenicova, L.; Skouboe, P.; Frisvad, Jens Christian;

    2001-01-01

    We examined nine Aspergillus japonicus isolates and 10 Aspergillus aculeatus isolates by using molecular and biochemical markers, including DNA sequences of the ITS1-5.8S rRNA gene-ITS2 region, restriction fragment length polymorphisms (RFLP), and secondary-metabolite profiles. The DNA sequence...... of the internal transcribed spacers (ITS1 and ITS2) and the 5.8S rRNA gene could not be used to distinguish between A. japonicus and A. aculeatus but did show that these two taxa are more closely related to each other than to other species of black aspergilli. Aspergillus niger pyruvate kinase (pkiA) and pectin...

  10. Aspergillus triggers phenazine production in Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Jensen, Britt Guillaume; Jelsbak, Lars; Søndergaard, Ib;

    Objectives: Pseudomonas aeruginosa is an opportunistic human pathogen, commonly infecting cystic fibrosis (CF) patients. Aspergilli, especially Aspergillus fumigatus, are also frequently isolated from CF patients. Our aim was to examine the possible interaction between P. aeruginosa and different...... Aspergillus species. Methods: A suspension of fungal spores was streaked onto WATM agar plates. After 24 hours incubation at 37 °C, a P. aeruginosa overnight culture was streaked out perpendicular to the fungal streak. The plates were incubated at 37 °C for five days, examined and plugs were extracted...... in the contact area of A. niger, A. flavus, A. oryzae, but not A. fumigatus. In addition, other metabolites with UV chromophores similar to the phenazines were only found in the contact zone between Aspergillus and Pseudomonas. No change in secondary metabolite profiles were seen for the Aspergilli, when...

  11. A rare case of bilateral aspergillus endophthalmitis

    Directory of Open Access Journals (Sweden)

    Saurabh Gupta

    2015-12-01

    Full Text Available Aspergillus endophthalmitis is a devastating inflammatory condition of the intraocular cavities that may result in irreparable loss of vision and rapid destruction of the eye. Almost all cases in the literature have shown an identified source causing aspergillus endophthalmitis as a result of direct extension of disease. We present a rare case of bilateral aspergillus endophthalmitis. A 72-year-old woman with a history of diabetes mellitus, congenital Hirschsprung disease, and recent culture-positive candida pyelonephritis with hydronephrosis status post-surgical stent placement presented with difficulty opening her eyes. She complained of decreased vision (20/200 with pain and redness in both eyes – right worse then left. Examination demonstrated multiple white fungal balls in both retinas consistent with bilateral fungal endophthalmitis. Bilateral vitreous taps for cultures and staining were performed. Patient was given intravitreal injections of amphotericin B, vancomycin, ceftazidime, and started on oral fluconazole. Patient was scheduled for vitrectomy to decrease organism burden and to remove loculated areas of infection that would not respond to systemic antifungal agents. Four weeks after initial presentation, the fungal cultures revealed mold growth consistent with aspergillus. Patient was subsequently started on voriconazole and fluconazole was discontinued due to poor efficacy against aspergillus. Further workup was conducted to evaluate for the source of infection and seeding. Transthoracic cardiogram was unremarkable for any vegetation or valvular abnormalities. MRI of the orbits and sinuses did not reveal any mass lesions or bony destruction. CT of the chest was unremarkable for infection. Aspergillus endophthalmitis may occur because of one of these several mechanisms: hematogenous dissemination, direct inoculation by trauma, and contamination during surgery. Our patient's cause of bilateral endophthalmitis was through an

  12. A new approach for molecular cloning in cyanobacteria: cloning of an anacystis nidulans met gene using a Tn 907-induced mutant

    NARCIS (Netherlands)

    Tandeau de Marsac, N.; Borrias, W.E.; Kuhlemeijer, C.J.; Castets, A.M.; Arkel, G.A. van; Hondel, C.A.M.J.J. van den

    1982-01-01

    A new strategy for molecular cloning in the cyanobacterium Anacystis nidulans R-2 is described. This strategy involved the use of a transposon and was developed for the cloning of a gene encoding methionine biosynthesis. A met::Tn 901 mutant was isolated. Chromosomal DNA fragments were cloned in the

  13. Bisulfite sequencing reveals that Aspergillus flavus holds a hollow in DNA methylation

    DEFF Research Database (Denmark)

    Liu, Si-Yang; Lin, Jian-Qing; Wu, Hong-Long;

    2012-01-01

    data and the methylome comparisons with other fungi confirm that the DNA methylation level of this fungus is negligible. Further investigation into the DNA methyltransferase of Aspergillus uncovers its close relationship with RID-like enzymes as well as its divergence with the methyltransferase......Aspergillus flavus first gained scientific attention for its production of aflatoxin. The underlying regulation of aflatoxin biosynthesis has been serving as a theoretical model for biosynthesis of other microbial secondary metabolites. Nevertheless, for several decades, the DNA methylation status......, one of the important epigenomic modifications involved in gene regulation, in A. flavus remains to be controversial. Here, we applied bisulfite sequencing in conjunction with a biological replicate strategy to investigate the DNA methylation profiling of A. flavus genome. Both the bisulfite sequencing...

  14. Genomic sequences of Aspergillus flavus accessions in Georgia USA

    Data.gov (United States)

    US Agency for International Development — The data was produced as part of the Feed the Future Innovation Lab for Collaborative Research on Peanut Productivity and Aflatoxin Control (the Peanut &...

  15. Functional genomics analysis of the secretory pathway in Aspergillus niger

    NARCIS (Netherlands)

    Oliveira, J.M.

    2010-01-01

    Filamentous fungi can be found in the majority of habitats of our planet. The wide-spread presence of filamentous fungi is related to their versatile metabolism, which allows them to grow on simple substrates, such as nitrate, acetate, ethanol, ammonia, or on complex matter such as biopolymers from

  16. Two novel aflatoxin-producing Aspergillus species from Argentinean peanuts

    DEFF Research Database (Denmark)

    Pildain, M.B.; Frisvad, Jens Christian; Vaamonde, G.;

    2008-01-01

    Two novel species from Aspergillus section Flavi from different species of Arachis (peanuts) in Argentina are described as Aspergillus arachidicola sp. nov. and Aspergillus minisclerotigenes sp. nov. Their novel taxonomic status was determined using a polyphasic taxonomic approach with phenotypic...... (morphology and extrolite profiles) and molecular (beta-tubulin and calmodulin gene sequences) characters. A. minisclerotigenes resembles Aspergillus flavus and Aspergillus parvisclerotigenus in producing aflatoxins B-1 and B-2, cyclopiazonic acid, kojic acid and aspergillic acid, but in addition it produces...... and parasiticolide, and some strains produce aspergillic acid. The type strain of A. arachidicola is CBS 117610(T) =IBT 25020(T) and that of A. minisclerotigenes is CBS 117635(T) =IBT 27196(T). The Mycobank accession numbers for Aspergillus minisclerotigenes sp. nov. and Aspergillus arachidicola sp. nov...

  17. Identification of thermostable beta-xylosidase activities produced by Aspergillus brasiliensis and Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Mads; Lauritzen, H.K.; Frisvad, Jens Christian;

    2007-01-01

    Twenty Aspergillus strains were evaluated for production of extracellular cellulolytic and xylanolytic activities. Aspergillus brasiliensis, A. niger and A. japonicus produced the highest xylanase activities with the A. brasiliensis and A. niger strains producing thermostable beta-xylosidases. Th...... is a well known enzyme producer, this is the first report of xylanase and thermostable beta-xylosidase production from the newly identified, non-ochratoxin-producing species A. brasiliensis....

  18. Identification of thermostable β-xylosidase activities produced by Aspergillus brasiliensis and Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Mads; Lauritzen, Henrik Klitgaard; Frisvad, Jens Christian;

    2007-01-01

    Twenty Aspergillus strains were evaluated for production of extracellular cellulolytic and xylanolytic activities. Aspergillus brasiliensis, A. niger and A. japonicus produced the highest xylanase activities with the A. brasiliensis and A. niger strains producing thermostable beta-xylosidases. Th...... is a well known enzyme producer, this is the first report of xylanase and thermostable beta-xylosidase production from the newly identified, non-ochratoxin-producing species A. brasiliensis....

  19. Taxonomic Characterization and Secondary Metabolite Profiling of Aspergillus Section Aspergillus Contaminating Feeds and Feedstuffs.

    Science.gov (United States)

    Greco, Mariana; Kemppainen, Minna; Pose, Graciela; Pardo, Alejandro

    2015-09-02

    Xerophilic fungal species of the genus Aspergillus are economically highly relevant due to their ability to grow on low water activity substrates causing spoilage of stored goods and animal feeds. These fungi can synthesize a variety of secondary metabolites, many of which show animal toxicity, creating a health risk for food production animals and to humans as final consumers, respectively. Animal feeds used for rabbit, chinchilla and rainbow trout production in Argentina were analysed for the presence of xerophilic Aspergillus section Aspergillus species. High isolation frequencies (>60%) were detected in all the studied rabbit and chinchilla feeds, while the rainbow trout feeds showed lower fungal charge (25%). These section Aspergillus contaminations comprised predominantly five taxa. Twenty isolates were subjected to taxonomic characterization using both ascospore SEM micromorphology and two independent DNA loci sequencing. The secondary metabolite profiles of the isolates were determined qualitatively by HPLC-MS. All the isolates produced neoechinulin A, 17 isolates were positive for cladosporin and echinulin, and 18 were positive for neoechinulin B. Physcion and preechinulin were detected in a minor proportion of the isolates. This is the first report describing the detailed species composition and the secondary metabolite profiles of Aspergillus section Aspergillus contaminating animal feeds.

  20. Taxonomic Characterization and Secondary Metabolite Profiling of Aspergillus Section Aspergillus Contaminating Feeds and Feedstuffs

    Science.gov (United States)

    Greco, Mariana; Kemppainen, Minna; Pose, Graciela; Pardo, Alejandro

    2015-01-01

    Xerophilic fungal species of the genus Aspergillus are economically highly relevant due to their ability to grow on low water activity substrates causing spoilage of stored goods and animal feeds. These fungi can synthesize a variety of secondary metabolites, many of which show animal toxicity, creating a health risk for food production animals and to humans as final consumers, respectively. Animal feeds used for rabbit, chinchilla and rainbow trout production in Argentina were analysed for the presence of xerophilic Aspergillus section Aspergillus species. High isolation frequencies (>60%) were detected in all the studied rabbit and chinchilla feeds, while the rainbow trout feeds showed lower fungal charge (25%). These section Aspergillus contaminations comprised predominantly five taxa. Twenty isolates were subjected to taxonomic characterization using both ascospore SEM micromorphology and two independent DNA loci sequencing. The secondary metabolite profiles of the isolates were determined qualitatively by HPLC-MS. All the isolates produced neoechinulin A, 17 isolates were positive for cladosporin and echinulin, and 18 were positive for neoechinulin B. Physcion and preechinulin were detected in a minor proportion of the isolates. This is the first report describing the detailed species composition and the secondary metabolite profiles of Aspergillus section Aspergillus contaminating animal feeds. PMID:26364643

  1. Taxonomic Characterization and Secondary Metabolite Profiling of Aspergillus Section Aspergillus Contaminating Feeds and Feedstuffs

    Directory of Open Access Journals (Sweden)

    Mariana Greco

    2015-09-01

    Full Text Available Xerophilic fungal species of the genus Aspergillus are economically highly relevant due to their ability to grow on low water activity substrates causing spoilage of stored goods and animal feeds. These fungi can synthesize a variety of secondary metabolites, many of which show animal toxicity, creating a health risk for food production animals and to humans as final consumers, respectively. Animal feeds used for rabbit, chinchilla and rainbow trout production in Argentina were analysed for the presence of xerophilic Aspergillus section Aspergillus species. High isolation frequencies (>60% were detected in all the studied rabbit and chinchilla feeds, while the rainbow trout feeds showed lower fungal charge (25%. These section Aspergillus contaminations comprised predominantly five taxa. Twenty isolates were subjected to taxonomic characterization using both ascospore SEM micromorphology and two independent DNA loci sequencing. The secondary metabolite profiles of the isolates were determined qualitatively by HPLC-MS. All the isolates produced neoechinulin A, 17 isolates were positive for cladosporin and echinulin, and 18 were positive for neoechinulin B. Physcion and preechinulin were detected in a minor proportion of the isolates. This is the first report describing the detailed species composition and the secondary metabolite profiles of Aspergillus section Aspergillus contaminating animal feeds.

  2. Aspergillus niger mstA encodes a high affinity sugar/H+ symporter which is regulated in persponse to extracellular pH

    NARCIS (Netherlands)

    Kuyk, van P.A.; Diderich, J.A.; MacCabe, A.P.; Hererro, O.; Ruijter, G.J.G.; Visser, J.

    2004-01-01

    A sugar-transporter-encoding gene, mstA, which is a member of the major facilitator superfamily, has been cloned from a genomic DNA library of the filamentous fungus Aspergillus niger. To enable the functional characterization of MSTA, a full-length cDNA was expressed in a Saccharomyces cerevisiae s

  3. The transcriptional activator GaaR of Aspergillus niger is required for release and utilization of D-galacturonic acid from pectin

    NARCIS (Netherlands)

    Alazi, Ebru; Niu, Jing; Kowalczyk, Joanna E; Peng, Mao; Aguilar Pontes, Maria Victoria; van Kan, Jan A L; Visser, Jaap; de Vries, Ronald P; Ram, Arthur F J

    2016-01-01

    We identified the D-galacturonic acid (GA) responsive transcriptional activator GaaR of the saprotrophic fungus Aspergillus niger, which was found to be essential for growth on GA and polygalacturonic acid (PGA). Growth of the ΔgaaR strain was reduced on complex pectins. Genome-wide expression analy

  4. The transcriptional activator GaaR of Aspergillus niger is required for release and utilization of d-galacturonic acid from pectin

    NARCIS (Netherlands)

    Alazi, Ebru; Niu, Jing; Kowalczyk, Joanna E.; Peng, Mao; Aguilar Pontes, Maria Victoria; Kan, Van Jan A.L.; Visser, Jaap; Vries, De Ronald P.; Ram, Arthur F.J.

    2016-01-01

    We identified the d-galacturonic acid (GA)-responsive transcriptional activator GaaR of the saprotrophic fungus, Aspergillus niger, which was found to be essential for growth on GA and polygalacturonic acid (PGA). Growth of the ΔgaaR strain was reduced on complex pectins. Genome-wide expression anal

  5. Organic acid production by Aspergillus niger

    DEFF Research Database (Denmark)

    Jongh, Wian de

    2006-01-01

    . Specielt Aspergillus niger er interessant i forbindelse med produktion af organiske syrer, idet denne organisme tolerer lavt pH, kan give høje produktudbytter, og kan give høje produktiviteter som allerede illustreret i anvendelsen af denne organisme i produktionen af citronsyre. Disse faktorer gør A...

  6. Phylogeny and subgeneric taxonomy of Aspergillus

    DEFF Research Database (Denmark)

    Peterson, S.W.; Varga, Janos; Frisvad, Jens Christian;

    2008-01-01

    The phylogeny of the genus Aspergillus and its teleomorphs is discussed based on multilocus sequence data. DNA sequence analysis was used to formulate a nucleotide sequence framework of the genus and to analyze character changes in relationship to the phylogeny hypothesized from the DNA sequence ...

  7. Aspergillus bertholletius sp. nov. from Brazil Nuts

    DEFF Research Database (Denmark)

    Taniwaki, Marta H.; Pitt, John I.; Iamanaka, Beatriz T.;

    2012-01-01

    During a study on the mycobiota of brazil nuts (Bertholletia excelsa) in Brazil, a new Aspergillus species, A. bertholletius, was found, and is described here. A polyphasic approach was applied using morphological characters, extrolite data as well as partial beta-tubulin, calmodulin and ITS sequ...

  8. Interaction between maize seed and Aspergillus flavus

    Science.gov (United States)

    Aspergillus flavus is an opportunistic fungal pathogen that colonizes maize seeds and contaminates them with aflatoxin. The fungus is localized in the endosperm and aleurone. To investigate the plant microbe interaction, we conducted histological and molecular studies to characterize the internal co...

  9. New rhamnogalacturonan degrading enzymes from Aspergillus aculeatus.

    NARCIS (Netherlands)

    Mutter, M.

    1997-01-01

    Three new  rhamnogalacturonan degrading enzymes were purified from a commercial enzyme preparation, Pectinex Ultra SP, produced by the fungus Aspergillus aculeatus . Pectinex Ultra SP is industrially used in the mash treatment of apples and pears in juice production, increasing juice yield. Rhamnoga

  10. Aspergillus PCR: one step closer to standardization.

    NARCIS (Netherlands)

    White, P.L.; Bretagne, S.; Klingspor, L.; Melchers, W.J.G.; McCulloch, E.; Schulz, B.; Finnstrom, N.; Mengoli, C.; Barnes, R.A.; Donnelly, J.P.; Loeffler, J.

    2010-01-01

    PCR has been used as an aid in the diagnosis of invasive aspergillosis for almost 2 decades. A lack of standardization has limited both its acceptance as a diagnostic tool and multicenter clinical evaluations, preventing its inclusion in disease-defining criteria. In 2006, the European Aspergillus P

  11. Systemic analysis of the response of Aspergillus niger to ambient pH

    DEFF Research Database (Denmark)

    Andersen, Mikael Rørdam; Lehmann, Linda Olkjær; Nielsen, Jens

    2009-01-01

    three levels of pH. Results: With genome scale modeling with an optimization for extracellular proton-production, it was possible to reproduce the preferred pH levels for citrate and oxalate. Transcriptome analysis and clustering expanded upon these results and allowed the identification of 162 clusters......Background: The filamentous fungus Aspergillus niger is an exceptionally efficient producer of organic acids, which is one of the reasons for its relevance to industrial processes and commercial importance. While it is known that the mechanisms regulating this production are tied to the levels...... of ambient pH, the reasons and mechanisms for this are poorly understood. Methods: To cast light on the connection between extracellular pH and acid production, we integrate results from two genome-based strategies: A novel method of genome-scale modeling of the response, and transcriptome analysis across...

  12. New taxa in Aspergillus section Usti.

    Science.gov (United States)

    Samson, R A; Varga, J; Meijer, M; Frisvad, J C

    2011-06-30

    Based on phylogenetic analysis of sequence data, Aspergillus section Usti includes 21 species, inclucing two teleomorphic species Aspergillus heterothallicus (= Emericella heterothallica) and Fennellia monodii. Aspergillus germanicus sp. nov. was isolated from indoor air in Germany. This species has identical ITS sequences with A. insuetusCBS 119.27, but is clearly distinct from that species based on β-tubulin and calmodulin sequence data. This species is unable to grow at 37 °C, similarly to A. keveii and A. insuetus. Aspergillus carlsbadensis sp. nov. was isolated from the Carlsbad Caverns National Park in New Mexico. This taxon is related to, but distinct from a clade including A. calidoustus, A. pseudodeflectus, A. insuetus and A. keveii on all trees. This species is also unable to grow at 37 °C, and acid production was not observed on CREA. Aspergillus californicus sp. nov. is proposed for an isolate from chamise chaparral (Adenostoma fasciculatum) in California. It is related to a clade including A. subsessilis and A. kassunensis on all trees. This species grew well at 37 °C, and acid production was not observed on CREA. The strain CBS 504.65 from soil in Turkey showed to be clearly distinct from the A. deflectus ex-type strain, indicating that this isolate represents a distinct species in this section. We propose the name A. turkensis sp. nov. for this taxon. This species grew, although rather restrictedly at 37 °C, and acid production was not observed on CREA. Isolates from stored maize, South Africa, as a culture contaminant of Bipolaris sorokiniana from indoor air in Finland proved to be related to, but different from A. ustus and A. puniceus. The taxon is proposed as the new species A. pseudoustus. Although supported only by low bootstrap values, F. monodii was found to belong to section Usti based on phylogenetic analysis of either loci BLAST searches to the GenBank database also resulted in closest hits from section Usti. This species obviously

  13. Identifying and characterizing the most significant β-glucosidase of the novel species Aspergillus saccharolyticus

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, Anette; Ahring, Birgitte K.; Lubeck, Mette; Ubhayasekera, Wimal; Bruno, Kenneth S.; Culley, David E.; Lubeck, Peter S.

    2012-08-20

    A newly discovered fungal species, Aspergillus saccharolyticus, was found to produce a culture broth rich in beta-glucosidase activity. In this present work, the main beta-glucosidase of A. saccharolyticus responsible for the efficient hydrolytic activity was identified, isolated, and characterized. Ion exchange chromatography was used to fractionate the culture broth, yielding fractions with high beta-glucosidase activity and only one visible band on an SDS-PAGE gel. Mass spectrometry analysis of this band gave peptide matches to beta-glucosidases from aspergilli. Through a PCR approach using degenerate primers and genome walking, a 2919 base pair sequence encoding the 860 amino acid BGL1 polypeptide was determined. BGL1 of A. saccharolyticus has 91% and 82% identity with BGL1 from Aspergillus aculeatus and BGL1 from Aspergillus niger, respectively, both belonging to Glycoside hydrolase family 3. Homology modeling studies suggested beta-glucosidase activity with preserved retaining mechanism and a wider catalytic pocket compared to other beta-glucosidases. The bgl1 gene was heterologously expressed in Trichoderma reesei QM6a, purified, and characterized by enzyme kinetics studies. The enzyme can hydrolyze cellobiose, pNPG, and cellodextrins. The enzyme showed good thermostability, was stable at 50°C, and at 60°C it had a half-life of approximately 6 hours.

  14. Two novel species of Aspergillus section Nigri from Thai coffee beans

    DEFF Research Database (Denmark)

    Noonim, Paramee; Mahakarnchanakul, Warapa; Varga, Janos;

    2008-01-01

    Two novel species of Aspergillus section Nigri from Thai coffee beans are described as Aspergillus aculeatinus sp. nov. and Aspergillus sclerotiicarbonarius sp. nov. Their taxonomic status was determined using a polyphasic taxonomic approach with phenotypic (morphology and extrolite profiles...

  15. Phylogeny, identification and nomenclature of the genus Aspergillus

    DEFF Research Database (Denmark)

    Samson, R.A.; Visagie, C.M.; Houbraken, J.;

    2014-01-01

    Aspergillus comprises a diverse group of species based on morphological, physiological and phylogenetic characters, which significantly impact biotechnology, food production, indoor environments and human health. Aspergillus was traditionally associated with nine teleomorph genera, but phylogenetic...... data suggest that together with genera such as Polypaecilum, Phialosimplex, Dichotomomyces and Cristaspora, Aspergillus forms a monophyletic clade closely related to Penicillium. Changes in the International Code of Nomenclature for algae, fungi and plants resulted in the move to one name per species......, meaning that a decision had to be made whether to keep Aspergillus as one big genus or to split it into several smaller genera. The International Commission of Penicillium and Aspergillus decided to keep Aspergillus instead of using smaller genera. In this paper, we present the arguments for this decision...

  16. Sex, drugs and recombination: the wild life of Aspergillus.

    Science.gov (United States)

    Fisher, Matthew C; Henk, Daniel A

    2012-03-01

    Throughout the eukaryotes, sexual reproduction is an almost universal phenomenon. However, within the Kingdom Fungi, this relationship is not so clear-cut. Fungi exhibit a spectrum of reproductive modes and life-cycles; amongst the better known species, sexual reproduction is often facultative, can be rare, and in over half of the known Ascomycota (the moulds) is unknown (Taylor et al. 1999). However, over the last decade, it has become apparent that many of these asexual mitosporic taxa undergo cryptic recombination via unobserved mechanisms and that wholly asexual fungi are, in fact, a rarity (Taylor et al. 1999, 2001; Heitman 2010). This revolution in our understanding of fungal sexuality has come about in two ways: Firstly, sexual reproduction leaves an imprint on fungal genomes by maintaining genes required for mating and by generating patterns of mutation and recombination restricted to meiotic processes. Secondly, scientists have become better at catching fungi in flagrante delicto. The genus Aspergillus is one such fungus where a combination of population genetics, genomics and taxonomy has been able to intuit the existence of sex, then to catch the fungus in the act and formally describe their sexual stages. So, why are sexy moulds exciting? One species in particular, Aspergillus flavus, is notorious for its ability to produce a diverse array of secondary metabolites, of which the polyketide aflatoxins (AF) are carcinogenic and others (such as cyclopiazonic acid) are toxigenic. Because of the predilection of A. flavus to grow on crops, such as peanuts, corn and cotton, biocontrol is widely used to mitigate infection by pre-applying nonaflatoxigenic (AF-) strains to competitively exclude the wild-type AF+ strains. However, the eventual fate in nature of these biocontrol strains is not known. In this issue of Molecular Ecology, Olarte et al. (2012) make an important contribution by using laboratory crosses of A. flavus to show that not only is AF highly

  17. In vitro interactions of antifungal agents and tacrolimus against Aspergillus biofilms.

    Science.gov (United States)

    Gao, Lujuan; Sun, Yi

    2015-11-01

    Aspergillus biofilms were prepared from Aspergillus fumigatus, Aspergillus flavus, and Aspergillus terreus via a 96-well plate-based method, and the combined antifungal activity of tacrolimus with azoles or amphotericin B against Aspergillus biofilms was investigated via a broth microdilution checkerboard technique system. Our results suggest that combinations of tacrolimus with voriconazole or amphotericin B have synergistic inhibitory activity against Aspergillus biofilms. However, combinations of tacrolimus with itraconazole or posaconazole exhibit no synergistic or antagonistic effects.

  18. CYANOBACTERIAL BIOMASS AS N-SUPPLEMENT TO OIL PALM EMPTY FRUIT BUNCH (OPEFB FIBRE FOR IMPROVEMENT OF CELLULASE PRODUCTION BY ASPERGILLUS TERREUS IN SUBMERGED FERMENTATION

    Directory of Open Access Journals (Sweden)

    Mahdi Shahriarinour

    2011-03-01

    Full Text Available The possibility of using dry biomass of a cyanobacterium, Anacystis nidulans, as nitrogen source supplement for improvement of cellulase production by Aspergillus terreus was studied in submerged fermentation using oil palm empty fruit bunch (OPEFB fibre as a carbon source. For comparison, four other nitrogen sources (ammonium sulphate, urea, peptone, and yeast extract were also tested. Growth and cellulase production were greatly enhanced in fermentation using biomass of cyanobacterium as the nitrogen source. The use of cyanobacterial biomass as a nitrogen source also reduced the inhibitory effect of high concentrations of CaCl2 to growth of A. terreus and cellulase production. The addition of 0.3 g L-1 CaCl2 to the medium containing OPEFB fibre and cyanobacterial biomass further enhanced the cellulase production, though growth remained unchanged. The final FPase, CMCase, and β-glucosidase obtained in fermentation using 10 g L-1 OPEFB fibre and 6 g/L cynaobacterial biomass with the addition of 3 mM CaCl2 was 0.97 U mL-1, 14.1 U mL-1, and 10.4 U mL-1, respectively.

  19. Deletion of the Ustilago maydis ortholog of the Aspergillus sporulation regulator medA affects mating and virulence through pheromone response.

    Science.gov (United States)

    Chacko, Nadia; Gold, Scott

    2012-06-01

    Mating of compatible haploid cells of Ustilago maydis is essential for infection and disease development in the host. For mating and subsequent filamentous growth and pathogenicity, the transcription factor, prf1 is necessary. Prf1 is in turn regulated by the cAMP and MAPK pathways and other regulators like rop1 and hap1. Here we describe the identification of another putative Prf1 regulator, med1, the ortholog of the Aspergillus nidulans medusa (medA) transcription factor and show that it is required for mating and full virulence in U. maydis. med1 deletion mutants show both pre- and post-mating defects and are unresponsive to external pheromone. The expression of prf1 is down-regulated in Δmed1 compared to the wild type, suggesting that med1 is upstream of prf1. Additionally, indicative of a role in secondary metabolism regulation, deletion of the med1 gene de-represses the production of glycolipids in U. maydis.

  20. Increased enzyme production under liquid culture conditions in the industrial fungus Aspergillus oryzae by disruption of the genes encoding cell wall α-1,3-glucan synthase.

    Science.gov (United States)

    Miyazawa, Ken; Yoshimi, Akira; Zhang, Silai; Sano, Motoaki; Nakayama, Mayumi; Gomi, Katsuya; Abe, Keietsu

    2016-09-01

    Under liquid culture conditions, the hyphae of filamentous fungi aggregate to form pellets, which reduces cell density and fermentation productivity. Previously, we found that loss of α-1,3-glucan in the cell wall of the fungus Aspergillus nidulans increased hyphal dispersion. Therefore, here we constructed a mutant of the industrial fungus A. oryzae in which the three genes encoding α-1,3-glucan synthase were disrupted (tripleΔ). Although the hyphae of the tripleΔ mutant were not fully dispersed, the mutant strain did form smaller pellets than the wild-type strain. We next examined enzyme productivity under liquid culture conditions by transforming the cutinase-encoding gene cutL1 into A. oryzae wild-type and the tripleΔ mutant (i.e. wild-type-cutL1, tripleΔ-cutL1). A. oryzae tripleΔ-cutL1 formed smaller hyphal pellets and showed both greater biomass and increased CutL1 productivity compared with wild-type-cutL1, which might be attributable to a decrease in the number of tripleΔ-cutL1 cells under anaerobic conditions. PMID:27442340

  1. Degradation of melanin by Aspergillus fumigatus.

    OpenAIRE

    Luther, J P; Lipke, H.

    1980-01-01

    A strain of Aspergillus fumigatus from composted coffee and garden wastes utilized natural deproteinized insect, banana, hair, octopus, and synthetic tyrosine and dopa melanins as sole sources of carbon. With a sucrose supplement, degradation was essentially complete after 50 days in Czapek medium pH 6.5 at 30 degrees C. The catabolic rate differed for each substrate pigment, as did the molecular weight distribution of products accumulating in the medium. After incubation with L-[U-14C]melani...

  2. SYNTHESIS OF COPPER NANOPARTICLES BY ASPERGILLUS SPECIES

    OpenAIRE

    Kantabathini Venkata Pavani; Nandigam Srujana; Guntur Preethi; Tandale Swati

    2013-01-01

    Recent developments in the biosynthesis of nanomaterials have demonstrated the important role of microorganisms in nanotechnology. The organisms show a unique potential in environmentally friendly production and accumulation of nanoparticles with different shapes and sizes. The present study proposed a green process for synthesis of copper nanoparticles using Aspergillus species. Syntheses of copper nanoparticles were characterized by UV-visible spectroscopy. The extracellular synthesis of co...

  3. SYNTHESIS OF COPPER NANOPARTICLES BY ASPERGILLUS SPECIES

    Directory of Open Access Journals (Sweden)

    Kantabathini Venkata Pavani

    2013-06-01

    Full Text Available Recent developments in the biosynthesis of nanomaterials have demonstrated the important role of microorganisms in nanotechnology. The organisms show a unique potential in environmentally friendly production and accumulation of nanoparticles with different shapes and sizes. The present study proposed a green process for synthesis of copper nanoparticles using Aspergillus species. Syntheses of copper nanoparticles were characterized by UV-visible spectroscopy. The extracellular synthesis of copper nanoparticles was characterized by scanning electron microscopy and Transmission electron microscopy.

  4. Expression of acid protease from Aspergillus kawachii in Aspergillus niger%白曲霉酸性蛋白酶在黑曲霉中表达

    Institute of Scientific and Technical Information of China (English)

    李杰; 吴婷; 马南; 王欣; 杨建乐; 李健友; 张会

    2016-01-01

    研究分析固态发酵酸性蛋白酶生产菌株及其产品,ITS序列鉴定结果表明,该菌株为曲霉属,质谱分析结果表明其产品为Aspergillus saitoi酸性蛋白酶Aspergillopepsin I(EC.3.4.23.18)。根据Aspergillus saitoi酸性蛋白酶Aspergillopepsin I基因序列pep1(GI:473517)设计引物,以固态发酵酸性蛋白酶生产菌株基因组DNA为模板,利用PCR技术扩增获得pep1基因。序列分析结果表明,扩增片段与白曲霉Aspergillus kawachii酸性蛋白酶基因组序列相似性为99%,其编码蛋白与白曲霉Aspergillus kawachii酸性蛋白酶(GAA90749.1)相似性为100%,将该基因命名为pepB。构建黑曲霉表达载体pSZHG-pepB,通过农杆菌介导法转化黑曲霉CICC2462,筛选得到在glaA位点发生同源重组纯合转化子。经摇瓶发酵后,对产物进行SDS-PAGE、酶活检测以及酸性蛋白酶酶学性质和酶稳定性研究。结果表明,纯合同源重组菌株经SDS-PAGE检测时在47 ku左右处有明显目的蛋白条带,其发酵产物酸性蛋白酶酶活达5543 U·mL-1,为出发菌株152倍。对菌株所产酸性蛋白酶酶学性质研究发现,该酶最适反应温度为50℃,最适反应pH 3.0,在4℃和25℃条件下,酶在pH 3.0~4.0时较稳定。%In this study, solid fermentation acid protease's producing strain from Zhaodong Richeng enzyme Ltd. and its products were analyzed , ITS sequence indicated that the strain belongs to the genus Aspergillus and mass spectrometric analysis showed that its product was acidic protease Aspergillopepsin I (EC.3.4.23.18) of Aspergillus saitoi. According to gene sequence of pep1 (GI:473517) from acid protease Aspergillopepsin I of Aspergillus saitoi, primers were designed, producing strain's genomic DNA from Solid-state fermentation acid protease as the template, and by the method of PCR, pep1 gene was cloned. Sequence analysis showed that amplified fragment was 99%similar to acid protease

  5. Prospecting for the incidence of genes involved in ochratoxin and fumonisin biosynthesis in Brazilian strains of Aspergillus niger and Aspergillus welwitschiae.

    Science.gov (United States)

    Massi, Fernanda Pelisson; Sartori, Daniele; de Souza Ferranti, Larissa; Iamanaka, Beatriz Thie; Taniwaki, Marta Hiromi; Vieira, Maria Lucia Carneiro; Fungaro, Maria Helena Pelegrinelli

    2016-03-16

    Aspergillus niger "aggregate" is an informal taxonomic rank that represents a group of species from the section Nigri. Among A. niger "aggregate" species Aspergillus niger sensu stricto and its cryptic species Aspergillus welwitschiae (=Aspergillus awamori sensu Perrone) are proven as ochratoxin A and fumonisin B2 producing species. A. niger has been frequently found in tropical and subtropical foods. A. welwitschiae is a new species, which was recently dismembered from the A. niger taxon. These species are morphologically very similar and molecular data are indispensable for their identification. A total of 175 Brazilian isolates previously identified as A. niger collected from dried fruits, Brazil nuts, coffee beans, grapes, cocoa and onions were investigated in this study. Based on partial calmodulin gene sequences about one-half of our isolates were identified as A. welwitschiae. This new species was the predominant species in onions analyzed in Brazil. A. niger and A. welwitschiae differ in their ability to produce ochratoxin A and fumonisin B2. Among A. niger isolates, approximately 32% were OTA producers, but in contrast only 1% of the A. welwitschiae isolates revealed the ability to produce ochratoxin A. Regarding fumonisin B2 production, there was a higher frequency of FB2 producing isolates in A. niger (74%) compared to A. welwitschiae (34%). Because not all A. niger and A. welwitschiae strains produce ochratoxin A and fumonisin B2, in this study a multiplex PCR was developed for detecting the presence of essential genes involved in ochratoxin (polyketide synthase and radHflavin-dependent halogenase) and fumonisin (α-oxoamine synthase) biosynthesis in the genome of A. niger and A. welwitschiae isolates. The frequency of strains harboring the mycotoxin genes was markedly different between A. niger and A. welwitschiae. All OTA producing isolates of A. niger and A. welwitschiae showed in their genome the pks and radH genes, and 95.2% of the nonproducing

  6. Functional analysis of Abp1p-interacting proteins involved in endocytosis of the MCC component in Aspergillus oryzae.

    Science.gov (United States)

    Matsuo, Kento; Higuchi, Yujiro; Kikuma, Takashi; Arioka, Manabu; Kitamoto, Katsuhiko

    2013-07-01

    We have investigated the functions of three endocytosis-related proteins in the filamentous fungus Aspergillus oryzae. Yeast two-hybrid screening using the endocytic marker protein AoAbp1 (A.oryzae homolog of Saccharomyces cerevisiae Abp1p) as a bait identified four interacting proteins named Aip (AoAbp1 interacting proteins). In mature hyphae, EGFP (enhanced green fluorescent protein) fused to Aips colocalized with AoAbp1 at the hyphal tip region and the plasma membrane, suggesting that Aips function in endocytosis. aipA is a putative AAA ATPase and its function has been dissected (Higuchi et al., 2011). aipB, the homolog of A. nidulans myoA, encodes an essential class I myosin and its conditional mutant showed a germination defect. aipC and aipD do not contain any recognizable domains except some proline-rich regions which may interact with two SH3 (Src homology 3) domains of AoAbp1. Neither aipC nor aipD disruptants showed any defects in their growth, but the aipC disruptant formed less conidia compared with the control strain. In addition, the aipC disruptant was resistant to the triazole antifungal drugs that inhibit ergosterol biosynthesis. Although no aip disruptants showed any defects in the uptake of the fluorescent dye FM4-64, the endocytosis of the arginine permease AoCan1, one of the MCC (membrane compartment of Can1p) components, was delayed in both aipC and aipD disruptants. In A. oryzae, AoCan1 localized mainly at the plasma membrane in the basal region of hyphae, suggesting that different endocytic mechanisms exist in apical and basal regions of highly polarized cells. PMID:23597630

  7. Antibiotic Extraction as a Recent Biocontrol Method for Aspergillus Niger andAspergillus Flavus Fungi in Ancient Egyptian mural paintings

    Science.gov (United States)

    Hemdan, R. Elmitwalli; Fatma, Helmi M.; Rizk, Mohammed A.; Hagrassy, Abeer F.

    Biodeterioration of mural paintings by Aspergillus niger and Aspergillus flavus Fungi has been proved in different mural paintings in Egypt nowadays. Several researches have studied the effect of fungi on mural paintings, the mechanism of interaction and methods of control. But none of these researches gives us the solution without causing a side effect. In this paper, for the first time, a recent treatment by antibiotic "6 penthyl α pyrone phenol" was applied as a successful technique for elimination of Aspergillus niger and Aspergillus flavus. On the other hand, it is favorable for cleaning Surfaces of Murals executed by tembera technique from the fungi metabolism which caused a black pigments on surfaces.

  8. A novel non-thermostable deuterolysin from Aspergillus oryzae.

    Science.gov (United States)

    Maeda, Hiroshi; Katase, Toru; Sakai, Daisuke; Takeuchi, Michio; Kusumoto, Ken-Ichi; Amano, Hitoshi; Ishida, Hiroki; Abe, Keietsu; Yamagata, Youhei

    2016-09-01

    Three putative deuterolysin (EC 3.4.24.29) genes (deuA, deuB, and deuC) were found in the Aspergillus oryzae genome database ( http://www.bio.nite.go.jp/dogan/project/view/AO ). One of these genes, deuA, was corresponding to NpII gene, previously reported. DeuA and DeuB were overexpressed by recombinant A. oryzae and were purified. The degradation profiles against protein substrates of both enzymes were similar, but DeuB showed wider substrate specificity against peptidyl MCA-substrates compared with DeuA. Enzymatic profiles of DeuB except for thermostability also resembled those of DeuA. DeuB was inactivated by heat treatment above 80° C, different from thermostable DeuA. Transcription analysis in wild type A. oryzae showed only deuB was expressed in liquid culture, and the addition of the proteinous substrate upregulated the transcription. Furthermore, the NaNO3 addition seems to eliminate the effect of proteinous substrate for the transcription of deuB. PMID:27050120

  9. Proteomic profile of Aspergillus flavus in response to water activity.

    Science.gov (United States)

    Zhang, Feng; Zhong, Hong; Han, Xiaoyun; Guo, Zhenni; Yang, Weiqiang; Liu, Yongfeng; Yang, Kunlong; Zhuang, Zhenhong; Wang, Shihua

    2015-03-01

    Aspergillus flavus, a common contaminant of crops and stored grains, can produce aflatoxins that are harmful to humans and other animals. Water activity (aw) is one of the key factors influencing both fungal growth and mycotoxin production. In this study, we used the isobaric tagging for relative and absolute quantitation (iTRAQ) technique to investigate the effect of aw on the proteomic profile of A. flavus. A total of 3566 proteins were identified, of which 837 were differentially expressed in response to variations in aw. Among these 837 proteins, 403 were over-expressed at 0.99 aw, whereas 434 proteins were over-expressed at 0.93 aw. According to Gene Ontology (GO) analysis, the secretion of extracellular hydrolases increased as aw was raised, suggesting that extracellular hydrolases may play a critical role in induction of aflatoxin biosynthesis. On the basis of Clusters of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) categorizations, we identified an exportin protein, KapK, that may down-regulate aflatoxin biosynthesis by changing the location of NirA. Finally, we considered the role of two osmotic stress-related proteins (Sln1 and Glo1) in the Hog1 pathway and investigated the expression patterns of proteins related to aflatoxin biosynthesis. The data uncovered in this study are critical for understanding the effect of water stress on toxin production and for the development of strategies to control toxin contamination of agricultural products.

  10. Plant-like biosynthesis of isoquinoline alkaloids in Aspergillus fumigatus.

    Science.gov (United States)

    Baccile, Joshua A; Spraker, Joseph E; Le, Henry H; Brandenburger, Eileen; Gomez, Christian; Bok, Jin Woo; Macheleidt, Juliane; Brakhage, Axel A; Hoffmeister, Dirk; Keller, Nancy P; Schroeder, Frank C

    2016-06-01

    Natural product discovery efforts have focused primarily on microbial biosynthetic gene clusters (BGCs) containing large multimodular polyketide synthases and nonribosomal peptide synthetases; however, sequencing of fungal genomes has revealed a vast number of BGCs containing smaller NRPS-like genes of unknown biosynthetic function. Using comparative metabolomics, we show that a BGC in the human pathogen Aspergillus fumigatus named fsq, which contains an NRPS-like gene lacking a condensation domain, produces several new isoquinoline alkaloids known as the fumisoquins. These compounds derive from carbon-carbon bond formation between two amino acid-derived moieties followed by a sequence that is directly analogous to isoquinoline alkaloid biosynthesis in plants. Fumisoquin biosynthesis requires the N-methyltransferase FsqC and the FAD-dependent oxidase FsqB, which represent functional analogs of coclaurine N-methyltransferase and berberine bridge enzyme in plants. Our results show that BGCs containing incomplete NRPS modules may reveal new biosynthetic paradigms and suggest that plant-like isoquinoline biosynthesis occurs in diverse fungi. PMID:27065235

  11. Transcriptome analysis of Aspergillus niger grown on sugarcane bagasse

    Directory of Open Access Journals (Sweden)

    Goldman Gustavo H

    2011-10-01

    Full Text Available Abstract Background Considering that the costs of cellulases and hemicellulases contribute substantially to the price of bioethanol, new studies aimed at understanding and improving cellulase efficiency and productivity are of paramount importance. Aspergillus niger has been shown to produce a wide spectrum of polysaccharide hydrolytic enzymes. To understand how to improve enzymatic cocktails that can hydrolyze pretreated sugarcane bagasse, we used a genomics approach to investigate which genes and pathways are transcriptionally modulated during growth of A. niger on steam-exploded sugarcane bagasse (SEB. Results Herein we report the main cellulase- and hemicellulase-encoding genes with increased expression during growth on SEB. We also sought to determine whether the mRNA accumulation of several SEB-induced genes encoding putative transporters is induced by xylose and dependent on glucose. We identified 18 (58% of A. niger predicted cellulases and 21 (58% of A. niger predicted hemicellulases cellulase- and hemicellulase-encoding genes, respectively, that were highly expressed during growth on SEB. Conclusions Degradation of sugarcane bagasse requires production of many different enzymes which are regulated by the type and complexity of the available substrate. Our presently reported work opens new possibilities for understanding sugarcane biomass saccharification by A. niger hydrolases and for the construction of more efficient enzymatic cocktails for second-generation bioethanol.

  12. Cell biology of the Koji mold Aspergillus oryzae.

    Science.gov (United States)

    Kitamoto, Katsuhiko

    2015-01-01

    Koji mold, Aspergillus oryzae, has been used for the production of sake, miso, and soy sauce for more than one thousand years in Japan. Due to the importance, A. oryzae has been designated as the national micro-organism of Japan (Koku-kin). A. oryzae has been intensively studied in the past century, with most investigations focusing on breeding techniques and developing methods for Koji making for sake brewing. However, the understanding of fundamental biology of A. oryzae remains relatively limited compared with the yeast Saccharomyces cerevisiae. Therefore, we have focused on studying the cell biology including live cell imaging of organelles, protein vesicular trafficking, autophagy, and Woronin body functions using the available genomic information. In this review, I describe essential findings of cell biology of A. oryzae obtained in our study for a quarter of century. Understanding of the basic biology will be critical for not its biotechnological application, but also for an understanding of the fundamental biology of other filamentous fungi.

  13. Fatal coinfection with Legionella pneumophila serogroup 8 and Aspergillus fumigatus.

    Science.gov (United States)

    Guillouzouic, Aurélie; Bemer, Pascale; Gay-Andrieu, Françoise; Bretonnière, Cédric; Lepelletier, Didier; Mahé, Pierre-Joachim; Villers, Daniel; Jarraud, Sophie; Reynaud, Alain; Corvec, Stéphane

    2008-02-01

    Legionella pneumophila is an important cause of community-acquired and nosocomial pneumonia. We report on a patient who simultaneously developed L. pneumophila serogroup 8 pneumonia and Aspergillus fumigatus lung abscesses. Despite appropriate treatments, Aspergillus disease progressed with metastasis. Coinfections caused by L. pneumophila and A. fumigatus remain exceptional. In apparently immunocompetent patients, corticosteroid therapy is a key risk factor for aspergillosis.

  14. Chemodiversity in the genus Aspergillus

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Larsen, Thomas Ostenfeld

    2015-01-01

    to be characterized. The genus Aspergillus is cladistically holophyletic but phenotypically polythetic and very diverse and is associated to quite different sexual states. Following the one fungus one name system, the genus Aspergillus is restricted to a holophyletic clade that include the morphologically different...

  15. Nationwide Surveillance of Azole Resistance in Aspergillus Diseases.

    Science.gov (United States)

    Vermeulen, Edith; Maertens, Johan; De Bel, Annelies; Nulens, Eric; Boelens, Jerina; Surmont, Ignace; Mertens, Anna; Boel, An; Lagrou, Katrien

    2015-08-01

    Aspergillus disease affects a broad patient population, from patients with asthma to immunocompromised patients. Azole resistance has been increasingly reported in both clinical and environmental Aspergillus strains. The prevalence and clinical impact of azole resistance in different patient populations are currently unclear. This 1-year prospective multicenter cohort study aimed to provide detailed epidemiological data on Aspergillus resistance among patients with Aspergillus disease in Belgium. Isolates were prospectively collected in 18 hospitals (April 2011 to April 2012) for susceptibility testing. Clinical and treatment data were collected with a questionnaire. The outcome was evaluated to 1 year after a patient's inclusion. A total of 220 Aspergillus isolates from 182 patients were included. The underlying conditions included invasive aspergillosis (n = 122 patients), allergic bronchopulmonary aspergillosis (APBA) (n = 39 patients), chronic pulmonary aspergillosis (n = 10 patients), Aspergillus bronchitis (n = 7 patients), and aspergilloma (n = 5 patients). The overall azole resistance prevalence was 5.5% (95% confidence interval [CI] 2.8 to 10.2%) and was 7.0% (4/57; 95% CI, 2.3 to 17.2%) in patients with APBA, bronchitis, aspergilloma, or chronic aspergillosis and 4.6% in patients with invasive aspergillosis (5/108; 95% CI, 1.7 to 10.7%). The 6-week survival in invasive aspergillosis was 52.5%, while susceptibility testing revealed azole resistance in only 2/58 of the deceased patients. The clinical impact of Aspergillus fumigatus resistance was limited in our patient population with Aspergillus diseases.

  16. Aspergillus fumigatus conidial melanin modulates host cytokine response

    NARCIS (Netherlands)

    L.Y.A. Chai (Louis); M.G. Netea (Mihai); J. Sugui (Janyce); A.G. Vonk (Alieke); W.W.J. van de Sande (Wendy); A. Warris (Adilia); K.J. Kwon-Chung (Kyung); B. Jan Kullberg (Bart)

    2010-01-01

    textabstractMelanin biopigments have been linked to fungal virulence. Aspergillus fumigatus conidia are melanised and are weakly immunogenic. We show that melanin pigments on the surface of resting Aspergillus fumigatus conidia may serve to mask pathogen-associated molecular patterns (PAMPs)-induced

  17. Phylogeny, identification and nomenclature of the genus Aspergillus.

    Science.gov (United States)

    Samson, R A; Visagie, C M; Houbraken, J; Hong, S-B; Hubka, V; Klaassen, C H W; Perrone, G; Seifert, K A; Susca, A; Tanney, J B; Varga, J; Kocsubé, S; Szigeti, G; Yaguchi, T; Frisvad, J C

    2014-06-01

    Aspergillus comprises a diverse group of species based on morphological, physiological and phylogenetic characters, which significantly impact biotechnology, food production, indoor environments and human health. Aspergillus was traditionally associated with nine teleomorph genera, but phylogenetic data suggest that together with genera such as Polypaecilum, Phialosimplex, Dichotomomyces and Cristaspora, Aspergillus forms a monophyletic clade closely related to Penicillium. Changes in the International Code of Nomenclature for algae, fungi and plants resulted in the move to one name per species, meaning that a decision had to be made whether to keep Aspergillus as one big genus or to split it into several smaller genera. The International Commission of Penicillium and Aspergillus decided to keep Aspergillus instead of using smaller genera. In this paper, we present the arguments for this decision. We introduce new combinations for accepted species presently lacking an Aspergillus name and provide an updated accepted species list for the genus, now containing 339 species. To add to the scientific value of the list, we include information about living ex-type culture collection numbers and GenBank accession numbers for available representative ITS, calmodulin, β-tubulin and RPB2 sequences. In addition, we recommend a standard working technique for Aspergillus and propose calmodulin as a secondary identification marker. PMID:25492982

  18. Aspergillus pragensis sp nov discovered during molecular reidentification of clinical isolates belonging to Aspergillus section Candidi

    DEFF Research Database (Denmark)

    Lyskova, Pavlina; Hubka, Vit; Kolarik, Miroslav;

    2014-01-01

    The identity of nine clinical isolates recovered from Czech patients and presumptively identified as Aspergillus sp. section Candidi based on colony morphology was revised using sequences of beta-tubulin, calmodulin gene sequence, and internal transcribed spacer rDNA. Six isolates were from suspe...

  19. Aspergillus uvarum sp. nov., an uniseriate black Aspergillus species isolated from grapes in Europe

    DEFF Research Database (Denmark)

    Perrone, Giancarlo; Varga, János; Susca, Antonia;

    2008-01-01

    uvarum sp. nov. isolates produced secalonic acid, common to other Aspergillus japonicus-related taxa, and geodin, erdin and dihydrogeodin, which are not produced by any other black aspergilli. None of the isolates were found to produce ochratoxin A. The novel species is most closely related to two...

  20. Aspergillus brasiliensis sp. nov., a biseriate black Aspergillus species with world-wide distribution

    DEFF Research Database (Denmark)

    Varga, János; Kocsubé, Sándor; Tóth, Beáta;

    2007-01-01

    to produce ochratoxin A, kotanins, funalenone or pyranonigrins. The novel species was most closely related to A. niger, and was isolated from soil from Brazil, Australia, USA and The Netherlands, and from grape berries from Portugal. The type strain of Aspergillus brasiliensis sp. nov. is CBS 101740(T) (=IM...

  1. Bisulfite sequencing reveals that Aspergillus flavus holds a hollow in DNA methylation.

    Directory of Open Access Journals (Sweden)

    Si-Yang Liu

    Full Text Available Aspergillus flavus first gained scientific attention for its production of aflatoxin. The underlying regulation of aflatoxin biosynthesis has been serving as a theoretical model for biosynthesis of other microbial secondary metabolites. Nevertheless, for several decades, the DNA methylation status, one of the important epigenomic modifications involved in gene regulation, in A. flavus remains to be controversial. Here, we applied bisulfite sequencing in conjunction with a biological replicate strategy to investigate the DNA methylation profiling of A. flavus genome. Both the bisulfite sequencing data and the methylome comparisons with other fungi confirm that the DNA methylation level of this fungus is negligible. Further investigation into the DNA methyltransferase of Aspergillus uncovers its close relationship with RID-like enzymes as well as its divergence with the methyltransferase of species with validated DNA methylation. The lack of repeat contents of the A. flavus' genome and the high RIP-index of the small amount of remanent repeat potentially support our speculation that DNA methylation may be absent in A. flavus or that it may possess de novo DNA methylation which occurs very transiently during the obscure sexual stage of this fungal species. This work contributes to our understanding on the DNA methylation status of A. flavus, as well as reinforces our views on the DNA methylation in fungal species. In addition, our strategy of applying bisulfite sequencing to DNA methylation detection in species with low DNA methylation may serve as a reference for later scientific investigations in other hypomethylated species.

  2. Genomics of Industrial Aspergilli and Comparison with Toxigenic Relatives

    Science.gov (United States)

    Aspergillus oryzae has been widely used in Japanese fermentation industries for longer than a thousand years. A. oryzae produces large amounts of various hydrolytic enzymes and has been successfully applied to modern biotechnology. The A. oryzae genome size (37.5 Mb) is very close to those of A. f...

  3. Gene deletion of cytosolic ATP: citrate lyase leads to altered organic acid production in Aspergillus niger

    DEFF Research Database (Denmark)

    Meijer, Susan Lisette; Nielsen, Michael Lynge; Olsson, Lisbeth;

    2009-01-01

    With the availability of the genome sequence of the filamentous fungus Aspergillus niger, the use of targeted genetic modifications has become feasible. This, together with the fact that A. niger is well established industrially, makes this fungus an attractive micro-organism for creating a cell...... factory platform for production of chemicals. Using molecular biology techniques, this study focused on metabolic engineering of A. niger to manipulate its organic acid production in the direction of succinic acid. The gene target for complete gene deletion was cytosolic ATP: citrate lyase (acl), which...... the acl gene. Additionally, the total amount of organic acids produced in the deletion strain was significantly increased. Genome-scale stoichiometric metabolic model predictions can be used for identifying gene targets. Deletion of the acl led to increased succinic acid production by A. niger....

  4. Reduction of aflatoxin production by Aspergillus flavus and Aspergillus parasiticus in interaction with Streptomyces.

    Science.gov (United States)

    Verheecke, C; Liboz, T; Anson, P; Diaz, R; Mathieu, F

    2015-05-01

    The aim of this study is to investigate aflatoxin gene expression during Streptomyces-Aspergillus interaction. Aflatoxins are carcinogenic compounds produced mainly by Aspergillus flavus and Aspergillus parasiticus. A previous study has shown that Streptomyces-A. flavus interaction can reduce aflatoxin content in vitro. Here, we first validated this same effect in the interaction with A. parasiticus. Moreover, we showed that growth reduction and aflatoxin content were correlated in A. parasiticus but not in A. flavus. Secondly, we investigated the mechanisms of action by reverse-transcriptase quantitative PCR. As microbial interaction can lead to variations in expression of household genes, the most stable [act1, βtub (and cox5 for A. parasiticus)] were chosen using geNorm software. To shed light on the mechanisms involved, we studied during the interaction the expression of five genes (aflD, aflM, aflP, aflR and aflS). Overall, the results of aflatoxin gene expression showed that Streptomyces repressed gene expression to a greater level in A. parasiticus than in A. flavus. Expression of aflR and aflS was generally repressed in both Aspergillus species. Expression of aflM was repressed and was correlated with aflatoxin B1 content. The results suggest that aflM expression could be a potential aflatoxin indicator in Streptomyces species interactions. Therefore, we demonstrate that Streptomyces can reduce aflatoxin production by both Aspergillus species and that this effect can be correlated with the repression of aflM expression.

  5. Empyema necessitatis due to Aspergillus fumigatus.

    Science.gov (United States)

    Lee, Hyun Woo; Kim, Yeon Wook; Cho, Jaeyoung; Lee, Chang-Hoon

    2014-01-01

    We present an extremely rare case of empyema necessitatis secondary to Aspergillus fumigatus infection. A 58-year-old woman presented to our hospital with a painful skin rash on the right thorax. Three fistulas communicating with the pleural space were found. Since she did not show a clinical improvement despite antituberculous and antibacterial treatment, we looked for other causes. Pleural fungus culture showed A. fumigatus and chest wall biopsy revealed numerous fungal hyphae. Treatment with necrotic tissue debridement and antifungal agents was successful. PMID:25452298

  6. Aspergillus endophthalmitis in orthotopic liver transplantation

    Directory of Open Access Journals (Sweden)

    Hosseini Hamid

    2009-06-01

    Full Text Available In this report, we describe a patient with drug-induced liver failure who developed endogenous endophthalmitis after liver transplantation. Our patient′s clinical course was so fulminant that the eye was lost in less than 1 month, without any response to therapy. Recognition of this infection is important because many patients die of disseminated Aspergillus infection, which may be detected early with bedside funduscopic examination by an ophthalmologist. Probably if the patient had referred to us earlier, it may have been possible to save the eye.

  7. Scleral buckle infection with aspergillus flavus

    Directory of Open Access Journals (Sweden)

    Bouhaimed Manal

    2008-01-01

    Full Text Available Purpose: To present a case of scleral buckle infection with Aspergillus flavus in a tertiary eye center in Saudi Arabia. Methods: A retrospective case report of a 28-year-old Saudi male who presented with a six-month history of conjunctival injection and discharge from the left eye which had undergone uncomplicated conventional retinal detachment surgery, at the King Khaled Eye Specialist Hospital in Riyadh, Saudi Arabia, in the form of cryopexy, subretinal fluid drainage and scleral buckle (grooved segmental sponge and circumferential band with sleeve for a macula on retinal detachment four years earlier. A diagnosis of infected extruded scleral buckle was made and the buckle was removed. Results: The infected scleral buckle was removed under local anesthesia with administration of sub-conjunctival irrigation of 50 mg solution of Vancomycin, and sub-conjunctival injection of 25mg of Vancomycin. Post operative microbiological studies revealed infection with silver staining of moderate Aspergillus flavus hyphae. Visual acuity of the left eye improved from 20/200 before surgery to 20/60 in the two years follow-up visit. Conclusion: This case report indicates the importance of considering infection with multiple organisms - including fungal ones - in cases of scleral buckle infections in our population.

  8. Aspergillus pneumonia in renal transplant recipients

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-dong; HU Xiao-peng; YIN Hang; WANG Wei; ZHANG Xin; MA Lin-lin; WANG Yong

    2008-01-01

    Background Filamentous fungal infections are associated with a high morbidity and mortality in solid organ transplants.The present study aimed to investigate the aspergillus pneumonia in renal transplant recipients, and its diagnosis as well as treatment.Methods Approximately 2000 cases of renal transplants were retrospectively studied and we focused on cases hospitalized during August 1, 2005 and February 1, 2007, as the study period. The clinical database and electronic records were analyzed. Recently published literature was reviewed.Results There was more diabetes and hypertension in the infected group than in the non-infected group (86% vs 62% and 57% vs 39%, respectively). Eighty-six percent of recipients from the infected group had delayed graft function. Seven cases with aspergillus pneumonia were identified based on either fungal culture or radiology. Of the 7 cases, 4 died in a few days after diagnosis. Liposomal amphotericin B was used as a first-line therapy.Conclusions Incidences of fungal infection are increasing among renal transplant recipients. Early diagnosis and treatment are critical steps in curing aspergillosis.

  9. Chronological aging in conidia of pathogenic Aspergillus: Comparison between species.

    Science.gov (United States)

    Oliveira, Manuela; Pereira, Clara; Bessa, Cláudia; Araujo, Ricardo; Saraiva, Lucília

    2015-11-01

    Aspergillus fumigatus, Aspergillus flavus, Aspergillus terreus and Aspergillus niger are common airborne fungi, and the most frequent causative agents of human fungal infections. However, the resistance and lifetime persistence of these fungi in the atmosphere, and the mechanism of aging of Aspergillus conidia are unknown.With this work, we intended to study the processes underlying conidial aging of these four relevant and pathogenic Aspergillus species. Chronological aging was therefore evaluated in A. fumigatus, A. flavus, A. terreus and A. niger conidia exposed to environmental and human body temperatures. The results showed that the aging process in Aspergillus conidia involves apoptosis,with metacaspase activation, DNA fragmentation, and reactive oxygen species production, associated with secondary necrosis. Distinct results were observed for the selected pathogenic species. At environmental conditions, A. niger was the species with the highest resistance to aging, indicating a higher adaption to environmental conditions, whereas A. flavus followed by A. terreus were the most sensitive species. At higher temperatures (37 °C), A. fumigatus presented the longest lifespan, in accordance with its good adaptation to the human body temperature. Altogether,with this work new insights regarding conidia aging are provided, which may be useful when designing treatments for aspergillosis.

  10. 2-hydroxyisocaproic acid is fungicidal for Candida and Aspergillus species.

    Science.gov (United States)

    Sakko, M; Moore, C; Novak-Frazer, L; Rautemaa, V; Sorsa, T; Hietala, P; Järvinen, A; Bowyer, P; Tjäderhane, L; Rautemaa, R

    2014-04-01

    The amino acid derivative 2-hydroxyisocaproic acid (HICA) is a nutritional additive used to increase muscle mass. Low levels can be detected in human plasma as a result of leucine metabolism. It has broad antibacterial activity but its efficacy against pathogenic fungi is not known. The aim was to test the efficacy of HICA against Candida and Aspergillus species. Efficacy of HICA against 19 clinical and reference isolates representing five Candida and three Aspergillus species with variable azole antifungal sensitivity profiles was tested using a microdilution method. The concentrations were 18, 36 and 72 mg ml(-1) . Growth was determined spectrophotometrically for Candida isolates and by visual inspection for Aspergillus isolates, viability was tested by culture and impact on morphology by microscopy. HICA of 72 mg ml(-1) was fungicidal against all Candida and Aspergillus fumigatus and Aspergillus terreus isolates. Lower concentrations were fungistatic. Aspergillus flavus was not inhibited by HICA. HICA inhibited hyphal formation in susceptible Candida albicans and A. fumigatus isolates and affected cell wall integrity. In conclusion, HICA has broad antifungal activity against Candida and Aspergillus at concentrations relevant for topical therapy. As a fungicidal agent with broad-spectrum bactericidal activity, it may be useful in the topical treatment of multispecies superficial infections.

  11. Antifungal susceptibility profile of cryptic species of Aspergillus.

    Science.gov (United States)

    Alastruey-Izquierdo, Ana; Alcazar-Fuoli, Laura; Cuenca-Estrella, Manuel

    2014-12-01

    The use of molecular tools has led to the description of new cryptic species among different Aspergillus species complexes. Their frequency in the clinical setting has been reported to be between 10 and 15%. The susceptibility to azoles and amphotericin B of many of these species is low, and some of them, such as Aspergillus calidoustus or Aspergillus lentulus, are considered multi-resistant. The changing epidemiology, the frequency of cryptic species, and the different susceptibility profiles make antifungal susceptibility testing an important tool to identify the optimal antifungal agent to treat the infections caused by these species.

  12. Pulmonary hypersensitivity to Alternaria and Aspergillus in baker's asthma.

    Science.gov (United States)

    Klaustermeyer, W B; Bardana, E J; Hale, F C

    1977-05-01

    In two cases of baker's asthma pulmonary hypersensitivity was found to the fungi Alternaria and Aspergillus. Provocative bronchial challenge revealed a dual response; an immediate and an Arthus type hypersensitivity to Aspergillus in the first case. A primary binding assay revealed high titres of anti-Aspergillus antibody in the serum. In the second case intradermal and bronchial challenge suggested an immediate type I hypersensitivity response to Alternaria. The suspected organisms were present in the room air of the bakeries. It is suggested that an immunological response to these airborne fungi may have contributed to the pathogenesis of baker's asthma. PMID:561668

  13. Effect of gamma radiation on Aspergillus flavus and Aspergillus ochraceus ultrastructure and mycotoxin production

    International Nuclear Information System (INIS)

    The aim of this work was to study the effect of gamma radiation (2 kGy) on Aspergillus flavus and Aspergillus ochraceus ultrastructure. Moreover, the influence on aflatoxin B1 and ochratoxin A production was also observed. Irradiated A. flavus strain showed a dull orangish colony while control strain showed the typical green color. Minor differences were observed on stipes, metulae and conidia size between control and irradiated A. flavus and A. ochraceus strains. Irradiated fungi showed ultrastructural changes on cell wall, plasmalema and cytoplasm levels. The levels of mycotoxins produced by irradiated strains were two times greater than those produced by control strains. Successive transferences of irradiated strains on malt extract agar allowed the fungus to recuperate morphological characteristics. Although minor changes in the fungal morphology were observed, ultrastructural changes at cell wall level and the increase of mycotoxin production ability were observed. Inappropriate storage of irradiated food and feed would allow the development of potentially more toxicogenic fungal propagules.

  14. Antagonism of Aspergillus terreus to Sclerotinia sclerotiorum Antagonismo de Aspergillus terreus contra Sclerotinia sclerotiorum

    Directory of Open Access Journals (Sweden)

    Itamar S. Melo

    2006-12-01

    Full Text Available An Aspergillus terreus strain showed in vitro antagonistic activity against the plant pathogen Sclerotinia sclerotiorum (Lib. de Bary. The interaction between A. terreus and sclerotia revealed that the mycoparasite sporulated abundantly on the sclerotial surface. Cell breakdown due to host cell wall disruption was observed in inner rind cells, by a scanning electron microscopy.Uma linhagem de Aspergillus terreus mostrou forte atividade parasítica contra Sclerotinia sclerotiorum. Interações entre o patógeno e o antagonista revelaram que A. terreus esporulou profusamente sobre os escleródios. Quando visto em microscopia eletrônica de varredura, o antagonista mostra-se rompendo e lisando a parede celular e penetrando o interior do escleródio, onde se estabelece no tecido medular.

  15. Identification and toxigenic potential of the industrially important fungi, Aspergillus oryzae and Aspergillus sojae

    DEFF Research Database (Denmark)

    Jørgensen, Thomas R

    2007-01-01

    Mold strains belonging to the species Aspergillus oryzae and Aspergillus sojae are highly valued as koji molds in the traditional preparation of fermented foods, such as miso, sake, and shoyu, and as protein production hosts in modern industrial processes. A. oryzae and A. sojae are relatives....... sojae strains. Separation of A. oryzae and A. sojae from A. flavus and A. parasiticus, respectively, is inconsistent, and both morphologic and molecular evidence support conspecificity. The high degree of identity is reflected by the divergent identification of reference cultures maintained in culture...... collections. As close relatives of aflatoxin-producing wild molds, koji molds possess an aflatoxin gene homolog cluster. Some strains identified as A. oryzae and A. sojae have been implicated in aflatoxin production. Identification of a strain as A. oryzae or A. sojae is no guarantee of its inability...

  16. Effect of gamma radiation on Aspergillus flavus and Aspergillus ochraceus ultrastructure and mycotoxin production

    Science.gov (United States)

    Ribeiro, J.; Cavaglieri, L.; Vital, H.; Cristofolini, A.; Merkis, C.; Astoreca, A.; Orlando, J.; Carú, M.; Dalcero, A.; Rosa, C. A. R.

    2011-05-01

    The aim of this work was to study the effect of gamma radiation (2 kGy) on Aspergillus flavus and Aspergillus ochraceus ultrastructure. Moreover, the influence on aflatoxin B 1 and ochratoxin A production was also observed. Irradiated A. flavus strain showed a dull orangish colony while control strain showed the typical green color. Minor differences were observed on stipes, metulae and conidia size between control and irradiated A. flavus and A. ochraceus strains. Irradiated fungi showed ultrastructural changes on cell wall, plasmalema and cytoplasm levels. The levels of mycotoxins produced by irradiated strains were two times greater than those produced by control strains. Successive transferences of irradiated strains on malt extract agar allowed the fungus to recuperate morphological characteristics. Although minor changes in the fungal morphology were observed, ultrastructural changes at cell wall level and the increase of mycotoxin production ability were observed. Inappropriate storage of irradiated food and feed would allow the development of potentially more toxicogenic fungal propagules.

  17. Aspergillus pragensis sp. nov. discovered during molecular reidentification of clinical isolates belonging to Aspergillus section Candidi.

    Science.gov (United States)

    Hubka, Vit; Lyskova, Pavlina; Frisvad, Jens C; Peterson, Stephen W; Skorepova, Magdalena; Kolarik, Miroslav

    2014-08-01

    The identity of nine clinical isolates recovered from Czech patients and presumptively identified as Aspergillus sp. section Candidi based on colony morphology was revised using sequences of β-tubulin, calmodulin gene sequence, and internal transcribed spacer rDNA. Six isolates were from suspected and proven onychomycosis, one from otitis externa, and two associated with probable invasive aspergillosis. The results showed that one Aspergillus candidus isolate was the cause of otitis externa, and both isolates obtained from sputa of patients with probable invasive aspergillosis were reidentified as A. carneus (sect. Terrei) and A. flavus (sect. Flavi). Three isolates from nail scrapings were identified as A. tritici, a verified agent of nondermatophyte onychomycosis. One isolate from toenail was determined to be A. candidus and the two isolates belonged to a hitherto undescribed species, Aspergillus pragensis sp. nov. This species is well supported by phylogenetic analysis based on β-tubulin and calmodulin gene and is distinguishable from other members of sect. Candidi by red-brown reverse on malt extract agar, slow growth on Czapek-Dox agar and inability to grow at 37°C. A secondary metabolite analysis was also provided with comparison of metabolite spectrum to other species. Section Candidi now encompasses five species for which a dichotomous key based on colony characteristics is provided. All clinical isolates were tested for susceptibilities to selected antifungal agents using the Etest and disc diffusion method. Overall sect. Candidi members are highly susceptible to common antifungals.

  18. A novel fungal fruiting structure formed by Aspergillus niger and Aspergillus carbonarius in grape berries.

    Science.gov (United States)

    Pisani, Cristina; Nguyen, Trang Thoaivan; Gubler, Walter Douglas

    2015-09-01

    Sour rot, is a pre-harvest disease that affects many grape varieties. Sour rot symptoms include initial berry cracking and breakdown of berry tissue. This is a disease complex with many filamentous fungi and bacteria involved, but is usually initiated by Aspergillus niger or Aspergillus carbonarius. Usually, by the time one sees the rot there are many other organisms involved and it is difficult to attribute the disease to one species. In this study two species of Aspergillus were shown to produce a previously unknown fruiting structure in infected berries. The nodulous morphology, bearing conidia, suggests them to be an 'everted polymorphic stroma'. This structure forms freely inside the berry pulp and assumes multiple shapes and sizes, sometimes sclerotium-like in form. It is composed of a mass of vegetative hyphae with or without tissue of the host containing spores or fruiting bodies bearing spores. Artificially inoculated berries placed in soil in winter showed the possible overwintering function of the fruiting body. Inoculated berry clusters on standing vines produced fruiting structures within 21 d post inoculation when wounds were made at veraison or after (July-September). Histological studies confirmed that the fruiting structure was indeed fungal tissue.

  19. Engineering the Polyketide Cell Factory

    DEFF Research Database (Denmark)

    Mølgaard, Louise

    cerevisiae. Both organisms have well-known genetic tools available for gene targeting and heterologous expression. It has been the aim to create a stable expression platform with all genes integrated in the genome. This has been achieved through the use of two advanced genetic engineering systems for A...... sufficient titers. To improve the production of polyketides biological engineering principles have been applied for the development and engineering of microbial polyketide cell factories. The two biological hosts used for heterologous polyketide production were Aspergillus nidulans and Saccharomyces...... through the use of adaptive evolution, random mutagenesis and screening as well as metabolic engineering. Firstly, in silico guided metabolic engineering was used as a tool to direct metabolism towards higher levels of 6-MSA production in A. nidulans. 6-MSA was stably expressed in the A. nidulans genome...

  20. Aproximación genético-bioquímica al estudio de la asimilación de nitrato en la cianobacteria "Anacystis nidulans R2"

    OpenAIRE

    Madueño Albi, Francisco

    1987-01-01

    Tras mutagénesis con transposón se han aislado 19 estirpes de la Cianobacteria Anacystis nidulans R2 incapaces de crecer en medio con nitrato como única fuente de nitrógeno. Se distinguen tres diferentes fenotipos en relación a la a ... ctividad de las enzimas implicadas en la reducción del nitrato. La estirpe FM16 muestra tanto actividad nitrato reductasa como actividad nitrito reductasa FM2 carece de la actividad nitrito reductasa y las restantes 16 estirpes carecen de la actividad nitrat...

  1. Production of amylases by Aspergillus tamarii

    Directory of Open Access Journals (Sweden)

    Moreira Fabiana Guillen

    1999-01-01

    Full Text Available A strain of Aspergillus tamarii, a filamentous fungus isolated from soil, was able to produce both a-amylase and glucoamylase activities in mineral media supplemented with 1% (w/v starch or maltose as the carbon source. Static cultivation led to significantly higher yields than those obtained using shaking culture. The production of amylases was tolerant to a wide range of initial culture pH values (from 4 to 10 and temperature (from 25 to 42oC. Two amylases, one a-amylase and one glucoamylase, were separated by ion exchange chromatography. Both partially purified enzymes had optimal activities at pH values between 4.5 and 6.0 and were stable under acid conditions (pH 4.0-7.0. The enzymes exhibited optimal activities at temperatures between 50o and 60o C and were stable for more than ten hours at 55oC.

  2. Environmental fungicides and triazole resistance in Aspergillus.

    Science.gov (United States)

    Bowyer, Paul; Denning, David W

    2014-02-01

    Fungal diseases are problematic in both human health and agriculture. Treatment options are limited and resistance may emerge. The relatively recent recognition of triazole resistance in Aspergillus fumigatus has prompted questioning of the origin of resistance. While multiple mechanisms are described in clinical isolates from triazole-treated patients, some de novo resistance is also recognised, especially attributable to TR34 /L98H. Such strains probably arose in the environment, and, indeed, multiple studies have now demonstrated TR(34) /L98H triazole resistance strains of A. fumigatus from soil. Docking and other in vitro studies are consistent with environmental resistance induction through exposure to certain triazole fungicides, notably difenoconazole, propiconazole, epoxiconazole, bromuconazole and tebuconazole. This article addresses the potential implications of this issue for both human health and food security.

  3. Aspergillus antigen testing in bone marrow transplant recipients

    OpenAIRE

    Williamson, E; Oliver, D.; Johnson, E.; Foot, A.; D. Marks; Warnock, D.

    2000-01-01

    Aims—To assess the clinical usefulness of a commercial aspergillus antigen enzyme linked immunosorbent assay (ELISA) in the diagnosis of invasive aspergillosis (IA) in bone marrow transplant recipients, and to compare it with a commercial latex agglutination (LA) test.

  4. An amendment of Aspergillus section Candidi based on chemotaxonomical evidence

    DEFF Research Database (Denmark)

    Rahbaek, L.; Frisvad, Jens Christian; Christophersen, C.

    2000-01-01

    A novel 2,2 '-epoxy-terphenyllin, candidusin C, in addition to the well known secondary metabolites terphenyllin, 3-hydroxyterpenyllin and chlorflavonin, has been isolated from the chemically unexplored fungus Aspergillus campestris. The latter three are known secondary metabolites from Aspergillus...... candidus and therefore a large number of Aspergilli were screened for production of these compounds to see whether they could be regarded as chemotaxonomical indicators of section membership in the monotypic Aspergillus section Candidi. The results indicated that A. campestris and A. taichungensis should...... be placed in Candidi and this was further confirmed by morphological and physiological similarities. Three species outside the section Candidi produced candidusin related secondary metabolites: Aspergillus arenarius, A. ellipticus and Penicillium raistrickii. Chlorflavonin, however, was only found...

  5. Septic arthritis due to tubercular and Aspergillus co-infection

    Directory of Open Access Journals (Sweden)

    Mukesh Kumar

    2016-01-01

    Full Text Available Aspergillus septic arthritis is a rare and serious medical and surgical problem. It occurs mainly in immunocompromised patients. Aspergillus fumigatus is the most common causative organism followed by Aspergillus flavus. The most common site affected is knee followed by shoulder, ankle, wrist, hip and sacroiliac joint. Debridement and voriconazole are primary treatment of articular aspergilosis. To the best of our knowledge, there are no reported cases of co-infection of tuberculosis (TB and Aspergillus infecting joints. We report a case of co-infection of TB and A. flavus of hip and knee of a 60-year-old male, with type 2 diabetes mellitus. He was treated with debridement, intravenous voriconazole, and antitubercular drugs.

  6. Septic arthritis due to tubercular and Aspergillus co-infection.

    Science.gov (United States)

    Kumar, Mukesh; Thilak, Jai; Zahoor, Adnan; Jyothi, Arun

    2016-01-01

    Aspergillus septic arthritis is a rare and serious medical and surgical problem. It occurs mainly in immunocompromised patients. Aspergillus fumigatus is the most common causative organism followed by Aspergillus flavus. The most common site affected is knee followed by shoulder, ankle, wrist, hip and sacroiliac joint. Debridement and voriconazole are primary treatment of articular aspergilosis. To the best of our knowledge, there are no reported cases of co-infection of tuberculosis (TB) and Aspergillus infecting joints. We report a case of co-infection of TB and A. flavus of hip and knee of a 60-year-old male, with type 2 diabetes mellitus. He was treated with debridement, intravenous voriconazole, and antitubercular drugs.

  7. Polyphasic taxonomy of Aspergillus fumigatus and related species

    DEFF Research Database (Denmark)

    Hong, S.B.; Go, S.J.; Shin, H.D.;

    2005-01-01

    The variability within Aspergillus fumigalus Fresenius and related species was examined using macro-, micro-morphology, growth temperature regimes and extrolite patterns. In addition, DNA analyses including partial beta-tubulin, calmodulin and actin gene sequences were used. Detailed examination ...

  8. Aspergillus fumigatus Conidial Melanin Modulates Host Cytokine Response

    OpenAIRE

    Chai, Louis; Netea, Mihai; SUGUI, JANYCE; Vonk, Alieke; van de Sande, Wendy; Warris, Adilia; Kwon-Chung, Kyung; Jan Kullberg, Bart

    2009-01-01

    textabstractMelanin biopigments have been linked to fungal virulence. Aspergillus fumigatus conidia are melanised and are weakly immunogenic. We show that melanin pigments on the surface of resting Aspergillus fumigatus conidia may serve to mask pathogen-associated molecular patterns (PAMPs)-induced cytokine response. The albino conidia induced significantly more proinflammatory cytokines in human peripheral blood mononuclear cells (PBMC), as compared to melanised wild-type conidia. Blocking ...

  9. Immobilization of Isolated Lipase From Moldy Copra (Aspergillus Oryzae)

    OpenAIRE

    Seniwati

    2012-01-01

    Enzyme immobilization is a recovery technique that has been studied in several years, using support as a media to help enzyme dissolutions to the reaction substrate. Immobilization method used in this study was adsorption method, using specific lipase from Aspergillus oryzae. Lipase was partially purified from the culture supernatant of Aspergillus oryzae. Enzyme was immobilized by adsorbed on silica gel. Studies on free and immobilized lipase systems for determination of op...

  10. Immobilization of Isolated Lipase From Moldy Copra (Aspergillus Oryzae)

    OpenAIRE

    Seniwati Dali; A. B. D. Rauf Patong; M.Noor Jalaluddin; Pirman; Baharuddin Hamzah

    2011-01-01

    Enzyme immobilization is a recovery technique that has been studied in several years, using support as a media to help enzyme dissolutions to the reaction substrate. Immobilization method used in this study was adsorption method, using specific lipase from Aspergillus oryzae. Lipase was partially purified from the culture supernatant of Aspergillus oryzae. Enzyme was immobilized by adsorbed on silica gel. Studies on free and immobilized lipase systems for determination of optimum pH, optimum ...

  11. Significance and occurrence of fumonisins from Aspergillus niger

    OpenAIRE

    Mogensen, Jesper Mølgaard; Nielsen, Kristian Fog; Larsen, Thomas Ostenfeld; Frisvad, Jens Christian

    2012-01-01

    Fumonisins is a well-studied group of mycotoxins, mainly produced in maize by Fusarium species. However with the recent discovery of a fumonisin production by Aspergillus niger, other food commodities are at risk, since A. niger is a ubiquitous contaminant of many food and feed products. The objective of this thesis was to determine the significance and occurrence of fumonisins from Aspergillus niger in food, the frequency of fumonisin production in A. niger isolates, as well as studies of th...

  12. Utilization of Low-Cost Ellagitannins for Ellagic Acid Production and Antimicrobial Phenolics Enhancing By Aspergillus awamorii and Aspergillus oryzae

    International Nuclear Information System (INIS)

    Three fungal strains, Aspergillus awamorii A9, Aspergillus awamorii A23 and Aspergillus oryzae O2, were selected out of ten fungal strains for their activeness in converting pomegranate peel ellagitannins into ellagic acid. When pomegranate peel was fermented by Aspergillus awamorii A9, the highest yields of ellagic acid (7.93±0.23 mg/g solid substrate) and total soluble phenolics (14.61±0.36 mg/g solid substrate) were produced at 5 and 10 days of incubation, respectively. Also, blue berry pomace, red grape pomace, strawberry pomace were evaluated as low cost ellagitannin sources for ellagic acid and soluble phenolics production. The antimicrobial activity of soluble phenolics extracted from fermented pomegranate peel and strawberry pomace was tested against two food-borne pathogens (Escherichia coli and Salmonella typhimurium). This study also revealed that 3 kGy enhanced the activity of antimicrobial phenolics

  13. Identification and characterization of the polyketide synthase involved in ochratoxin A biosynthesis in Aspergillus carbonarius

    Energy Technology Data Exchange (ETDEWEB)

    Gallo, Antonia; Knox, Benjamin P.; Bruno, Kenneth S.; Solfrizzo, Michele; Baker, Scott E.; Perrone, Giancarlo

    2014-06-02

    Ochratoxin A (OTA) is a potent mycotoxin produced by Aspergillus and Penicillium species and is a common contaminant of a wide variety of food commodities, with Aspergillus carbonarius being the main producer of OTA contamination in grapes and wine. The molecular structure of OTA is composed of a dihydroisocoumarin ring linked to phenylalanine and, as shown in different producing fungal species, a polyketide synthase (PKS) is a component of the OTA biosynthetic pathway. Similar to observations in other filamentous ascomycetes, the genome sequence of A. carbonarius contains a large number of genes predicted to encode PKSs. In this work a pks gene identified within the putative OTA cluster of A. carbonarius, designated as AcOTApks, was inactivated and the resulting mutant strain was unable to produce OTA, confirming the role of AcOTApks in this biosynthetic pathway. AcOTApks protein is characteristic of the highly reduced (HR)-PKS family, and also contains a putative methyltransferase domain likely responsible for the addition of the methyl group to the OTA polyketide structure. AcOTApks is different from the ACpks protein that we previously described which showed an expression profile compatible with OTA production. We performed phylogenetic analyses of the β-ketosynthase and acyl-transferase domains of the OTA PKSs which had been identified and characterized in different OTA producing fungal species. The phylogenetic results were similar for both the two domains analyzed and showed that OTA PKS of A. carbonarius, Aspergillus niger, and Aspergillus ochraceus clustered in a monophyletic group with 100% bootstrap support suggesting a common origin, while the other OTA PKSs analyzed were phylogenetically distant. A qRT-PCR assay monitored AcOTApks expression during fungal growth and concomitant production of OTA by A. carbonarius in synthetic grape medium. A clear correlation between the expression profile of AcOTApks and kinetics of OTA production was observed with

  14. Identification and characterization of the polyketide synthase involved in ochratoxin A biosynthesis in Aspergillus carbonarius.

    Science.gov (United States)

    Gallo, Antonia; Knox, Benjamin P; Bruno, Kenneth S; Solfrizzo, Michele; Baker, Scott E; Perrone, Giancarlo

    2014-06-01

    Ochratoxin A (OTA) is a potent mycotoxin produced by Aspergillus and Penicillium species and is a common contaminant of a wide variety of food commodities, with Aspergillus carbonarius being the main producer of OTA contamination in grapes and wine. The molecular structure of OTA comprises a dihydroisocoumarin ring linked to phenylalanine and, as shown in different producing fungal species, a polyketide synthase (PKS) is a component of the OTA biosynthetic pathway. Similar to observations in other filamentous ascomycetes, the genome sequence of A. carbonarius contains a large number of genes predicted to encode PKSs. In this work a pks gene identified within the putative OTA cluster of A. carbonarius, designated as AcOTApks, was inactivated and the resulting mutant strain was unable to produce OTA, confirming the role of AcOTApks in this biosynthetic pathway. AcOTApks protein is characteristic of the highly reduced (HR)-PKS family, and also contains a putative methyltransferase domain likely responsible for the addition of the methyl group to the OTA polyketide structure. AcOTApks is different from the ACpks protein that we previously described in A. carbonarius, which showed an expression profile compatible with OTA production. We performed phylogenetic analyses of the β-ketosynthase and acyl-transferase domains of the OTA PKSs that had been identified and characterized in different OTA producing fungal species. The phylogenetic results were similar for both domains analyzed and showed that OTA PKS of A. carbonarius, Aspergillus niger and Aspergillus ochraceus clustered in a monophyletic group with 100% bootstrap support suggesting a common origin, while the other OTA PKSs analyzed were phylogenetically distant. A quantitative RT-PCR assay monitored AcOTApks expression during fungal growth and concomitant production of OTA by A. carbonarius in synthetic grape medium. A clear correlation between the expression profile of AcOTApks and kinetics of OTA production was

  15. Identification and characterization of the polyketide synthase involved in ochratoxin A biosynthesis in Aspergillus carbonarius.

    Science.gov (United States)

    Gallo, Antonia; Knox, Benjamin P; Bruno, Kenneth S; Solfrizzo, Michele; Baker, Scott E; Perrone, Giancarlo

    2014-06-01

    Ochratoxin A (OTA) is a potent mycotoxin produced by Aspergillus and Penicillium species and is a common contaminant of a wide variety of food commodities, with Aspergillus carbonarius being the main producer of OTA contamination in grapes and wine. The molecular structure of OTA comprises a dihydroisocoumarin ring linked to phenylalanine and, as shown in different producing fungal species, a polyketide synthase (PKS) is a component of the OTA biosynthetic pathway. Similar to observations in other filamentous ascomycetes, the genome sequence of A. carbonarius contains a large number of genes predicted to encode PKSs. In this work a pks gene identified within the putative OTA cluster of A. carbonarius, designated as AcOTApks, was inactivated and the resulting mutant strain was unable to produce OTA, confirming the role of AcOTApks in this biosynthetic pathway. AcOTApks protein is characteristic of the highly reduced (HR)-PKS family, and also contains a putative methyltransferase domain likely responsible for the addition of the methyl group to the OTA polyketide structure. AcOTApks is different from the ACpks protein that we previously described in A. carbonarius, which showed an expression profile compatible with OTA production. We performed phylogenetic analyses of the β-ketosynthase and acyl-transferase domains of the OTA PKSs that had been identified and characterized in different OTA producing fungal species. The phylogenetic results were similar for both domains analyzed and showed that OTA PKS of A. carbonarius, Aspergillus niger and Aspergillus ochraceus clustered in a monophyletic group with 100% bootstrap support suggesting a common origin, while the other OTA PKSs analyzed were phylogenetically distant. A quantitative RT-PCR assay monitored AcOTApks expression during fungal growth and concomitant production of OTA by A. carbonarius in synthetic grape medium. A clear correlation between the expression profile of AcOTApks and kinetics of OTA production was

  16. Validation of a new Aspergillus real-time PCR assay for direct detection of Aspergillus and azole resistance of Aspergillus fumigatus on bronchoalveolar lavage fluid.

    Science.gov (United States)

    Chong, Ga-Lai M; van de Sande, Wendy W J; Dingemans, Gijs J H; Gaajetaan, Giel R; Vonk, Alieke G; Hayette, Marie-Pierre; van Tegelen, Dennis W E; Simons, Guus F M; Rijnders, Bart J A

    2015-03-01

    Azole resistance in Aspergillus fumigatus is increasingly reported. Here, we describe the validation of the AsperGenius, a new multiplex real-time PCR assay consisting of two multiplex real-time PCRs, one that identifies the clinically relevant Aspergillus species, and one that detects the TR34, L98H, T289A, and Y121F mutations in CYP51A and differentiates susceptible from resistant A. fumigatus strains. The diagnostic performance of the AsperGenius assay was tested on 37 bronchoalveolar lavage (BAL) fluid samples from hematology patients and 40 BAL fluid samples from intensive care unit (ICU) patients using a BAL fluid galactomannan level of ≥1.0 or positive culture as the gold standard for detecting the presence of Aspergillus. In the hematology and ICU groups combined, there were 22 BAL fluid samples from patients with invasive aspergillosis (IA) (2 proven, 9 probable, and 11 nonclassifiable). Nineteen of the 22 BAL fluid samples were positive, according to the gold standard. The optimal cycle threshold value for the presence of Aspergillus was Aspergillus species and 14 A. fumigatus samples). This resulted in a sensitivity, specificity, and positive and negative predictive values of 88.9%, 89.3%, 72.7%, and 96.2%, respectively, for the hematology group and 80.0%, 93.3%, 80.0%, and 93.3%, respectively, in the ICU group. The CYP51A real-time PCR confirmed 12 wild-type and 2 resistant strains (1 TR34-L98H and 1 TR46-Y121F-T289A mutant). Voriconazole therapy failed for both patients. The AsperGenius multiplex real-time PCR assay allows for sensitive and fast detection of Aspergillus species directly from BAL fluid samples. More importantly, this assay detects and differentiates wild-type from resistant strains, even if BAL fluid cultures remain negative.

  17. Does fungicide application in vineyards induce resistance to medical azoles in Aspergillus species?

    Science.gov (United States)

    Lago, Magali; Aguiar, Ana; Natário, André; Fernandes, Carla; Faria, Miguel; Pinto, Eugénia

    2014-09-01

    This study assessed if the use of sterol demethylase inhibitor fungicides in vineyard production can induce resistance to azoles in Aspergillus strains and if it can induce selection of resistant species. We also tried to identify the Aspergillus species most prevalent in the vineyards. Two vineyards from northern Portugal were selected from "Vinhos Verdes" and "Douro" regions. The vineyards were divided into plots that were treated or not with penconazole (PEN). In each vineyard, air, soil, and plant samples were collected at three different times. The strains of Aspergillus spp. were isolated and identified by morphological and molecular techniques. We identified 46 Aspergillus section Nigri, eight Aspergillus fumigatus, seven Aspergillus lentulus, four Aspergillus wentii, two Aspergillus flavus, two Aspergillus terreus, one Aspergillus calidoustus, one Aspergillus westerdijkiae, one Aspergillus tamarii, and one Eurotium amstelodami. Aspergillus strains were evaluated for their susceptibility to medical azoles used in human therapy (itraconazole, posaconazole, and voriconazole) and to agricultural azoles (PEN) used in the prevention and treatment of plant diseases. The isolates showed moderate susceptibility to voriconazole. We did not observe any decrease of susceptibility to the medical azoles tested throughout the testing period in any of the treated plots, although some of the resistant species were isolated from there.

  18. Aspergillus fumigatus invasion increases with progressive airway ischemia.

    Directory of Open Access Journals (Sweden)

    Joe L Hsu

    Full Text Available Despite the prevalence of Aspergillus-related disease in immune suppressed lung transplant patients, little is known of the host-pathogen interaction. Because of the mould's angiotropic nature and because of its capacity to thrive in hypoxic conditions, we hypothesized that the degree of Aspergillus invasion would increase with progressive rejection-mediated ischemia of the allograft. To study this relationship, we utilized a novel orthotopic tracheal transplant model of Aspergillus infection, in which it was possible to assess the effects of tissue hypoxia and ischemia on airway infectivity. Laser Doppler flowmetry and FITC-lectin were used to determine blood perfusion, and a fiber optic microsensor was used to measure airway tissue oxygen tension. Fungal burden and depth of invasion were graded using histopathology. We demonstrated a high efficacy (80% for producing a localized fungal tracheal infection with the majority of infection occurring at the donor-recipient anastomosis; Aspergillus was more invasive in allogeneic compared to syngeneic groups. During the study period, the overall kinetics of both non-infected and infected allografts was similar, demonstrating a progressive loss of perfusion and oxygenation, which reached a nadir by days 10-12 post-transplantation. The extent of Aspergillus invasion directly correlated with the degree of graft hypoxia and ischemia. Compared to the midtrachea, the donor-recipient anastomotic site exhibited lower perfusion and more invasive disease; a finding consistent with clinical experience. For the first time, we identify ischemia as a putative risk factor for Aspergillus invasion. Therapeutic approaches focused on preserving vascular health may play an important role in limiting Aspergillus infections.

  19. Molecular characterization of Aspergillus infections in an Iranian educational hospital using RAPD-PCR method

    Directory of Open Access Journals (Sweden)

    Kambiz Diba

    2014-09-01

    Conclusion: The hospital sources for the Aspergillus clinical isolates included air condition and walls. RAPD-PCR analysis can play a trivial role to find the hospital sources of Aspergillus clinical isolates.

  20. The potential impact of the pulmonary microbiome on immunopathogenesis of Aspergillus-related lung disease

    NARCIS (Netherlands)

    Kolwijck, E.; Veerdonk, F.L. van de

    2014-01-01

    Aspergillosis is an infection or allergic response caused by fungi of the genus Aspergillus. The most common forms of aspergillosis are allergic bronchopulmonary aspergillosis, chronic pulmonary aspergillosis, and invasive pulmonary aspergillosis. Aspergillus also plays an important role in fungal s

  1. What is the importance of classifying Aspergillus disease in cystic fibrosis patients?

    Science.gov (United States)

    Jones, Andrew M; Horsley, Alex; Denning, David W

    2014-08-01

    Aspergillus species are commonly isolated from lower respiratory tract samples of patients with cystic fibrosis (CF) and markers of immunological sensation to Aspergillus are frequently encountered in this group of patients; however, the contribution of Aspergillus to CF lung disease outside of the typical complications of ABPA and aspergilloma formation remains largely unclear. Patients with CF show discretely different responses to Aspergillus, though the underlying reasons for this variation are unknown. Recent work has begun to allow us to categorize patient responses to Aspergillus based upon molecular markers of infection and immune sensitization. Aspergillus sensitization and/or airway infection is associated with worse FEV1, in CF and other patients (asthma, chronic obstructive pulmonary disease, bronchiectasis). Classification of different clinical phenotypes of Aspergillus will enable future studies to determine the natural history of different manifestations of Aspergillus disease and evaluate the effects of intervention with antifungal therapy.

  2. Detection and discrimination of four Aspergillus section Nigri species by PCR.

    Science.gov (United States)

    Palumbo, J D; O'Keeffe, T L

    2015-02-01

    Species of Aspergillus section Nigri are not easily distinguished by traditional morphological techniques, and typically are identified by DNA sequencing methods. We developed four PCR primers to distinguish between Aspergillus niger, Aspergillus welwitschiae, Aspergillus carbonarius and Aspergillus tubingensis, based on species-conserved differences in the calmodulin gene sequence. PCR amplification from total DNA using these primers was species specific; no amplification occurred from nontarget species DNA for each primer pair. Species-specific PCR could distinguish between species in mixed DNA templates, indicating a utility in determining culture uniformity of isolated Aspergillus strains. In addition, with these primer sets, each species could be detected in soil following mixed-species inoculation with Aspergillus spores. This indicates that PCR with these species-specific primers may be useful in determining the distribution of Aspergillus species in environmental samples without the need for species identification from isolated strains, as well as detecting species that may be infrequently isolated by culture-based methods.

  3. A new diketopiperazine alkaloid from Aspergillus oryzae.

    Science.gov (United States)

    Shaaban, Mohamed; El-Metwally, Mohammad Magdy; Nasr, Hamdi

    2014-01-01

    Investigation of bioactive secondary metabolites from terrestrial Aspergillus oryzae sp. MMAO1 using M2 medium afforded a new diketopiperazine alkaloid, 7,9-dihydroxy-3-(1H-indol-3-ylmethyl)-8-methoxy-2,3,11,11a-tetrahydro-6H-pyrazino[1,2-b]isoquinoline-1,4-dione (1a), containing the unusual amino acid L-6,8-dihydroxy-7-methoxyphenylalanine. This was co-isolated with ditryptophenaline (2), cyclo-(Tryp,Tyr) (4), cyclo-(Pro,Val), α-cyclopiazonic acid (3), kojic acid and uridine. Re-cultivation of the fungal strain on Dox medium led to the production of bisdethio(bismethylthio)gliotoxin (5), pseurotin A (6) along with linoleic acid, α-cyclopiazonic acid (3) and kojic acid. The chemical structure of the new diketopiperazine alkaloid including the relative configuration was determined by 1D and 2D NMR spectroscopy and HR-ESI-MS spectrometry, and by comparison with the related literature. The new alkaloid (1a) showed no antimicrobial activity or cytotoxicity against brine shrimps.

  4. Effect of gamma radiation on Aspergillus flavus and Aspergillus ochraceus ultrastructure and mycotoxin production

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, J. [Departamento de Microbiologia e Inmunologia Veterinaria, Universidad Federal Rural de Rio de Janeiro (UFRRJ) (Brazil); Cavaglieri, L., E-mail: lcavaglieri@arnet.com.a [Departamento de Microbiologia e Inmunologia, Universidad Nacional de Rio Cuarto (UNRC), Rio Cuarto, Cordoba (Argentina); Member of Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CIC-CONICET) (Argentina); Vital, H. [Centro Tecnologico do Exercito (CTEx), Secao de Defesa Nuclear, Rio de Janeiro (Brazil); Cristofolini, A.; Merkis, C. [Departamento de Microscopia Electronica, Universidad Nacional de Rio Cuarto. Ruta 36 km 601 (5800) Rio Cuarto (Argentina); Astoreca, A. [Departamento de Microbiologia e Inmunologia, Universidad Nacional de Rio Cuarto (UNRC), Rio Cuarto, Cordoba (Argentina); Member of Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CIC-CONICET) (Argentina); Orlando, J.; Caru, M. [Departamento de Ciencias Ecologicas, Facultad de Ciencias, Universidad de Chile, Santiago (Chile); Dalcero, A. [Departamento de Microbiologia e Inmunologia, Universidad Nacional de Rio Cuarto (UNRC), Rio Cuarto, Cordoba (Argentina); Member of Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CIC-CONICET) (Argentina); Rosa, C.A.R. [Departamento de Microbiologia e Inmunologia Veterinaria, Universidad Federal Rural de Rio de Janeiro (UFRRJ) (Brazil); Member of Consejo Nacional de Pesquisas (CNPq) (Brazil)

    2011-05-15

    The aim of this work was to study the effect of gamma radiation (2 kGy) on Aspergillus flavus and Aspergillus ochraceus ultrastructure. Moreover, the influence on aflatoxin B{sub 1} and ochratoxin A production was also observed. Irradiated A. flavus strain showed a dull orangish colony while control strain showed the typical green color. Minor differences were observed on stipes, metulae and conidia size between control and irradiated A. flavus and A. ochraceus strains. Irradiated fungi showed ultrastructural changes on cell wall, plasmalema and cytoplasm levels. The levels of mycotoxins produced by irradiated strains were two times greater than those produced by control strains. Successive transferences of irradiated strains on malt extract agar allowed the fungus to recuperate morphological characteristics. Although minor changes in the fungal morphology were observed, ultrastructural changes at cell wall level and the increase of mycotoxin production ability were observed. Inappropriate storage of irradiated food and feed would allow the development of potentially more toxicogenic fungal propagules.

  5. Ultrasonographic findings of aspergillus bursitis in a patient with a renal transplantation: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Byeong Seong; Yang, Myeon Jun; Kim, Young Min; Youm, Yoon Seok; Choi, Seong Hoon; Park, Sung Bin; Jeong, Ae Kyung [University of Ulsan College of Medicine, Ulsan University Hospital, Ulsan (Korea, Republic of)

    2008-04-15

    Aspergillus bursitis is an uncommon condition demonstrated as a nonspecific soft tissue mass. To our knowledge, the ultrasonographic findings of aspergillus bursitis in immunocompromised patients have not been previously reported. Here, we report a case of aspergillus bursitis in a renal transplant recipient, accompanied by the associated ultrasonographic findings.

  6. 40 CFR 180.1206 - Aspergillus flavus AF36; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Aspergillus flavus AF36; exemption... FOOD Exemptions From Tolerances § 180.1206 Aspergillus flavus AF36; exemption from the requirement of a... pesticide Aspergillus flavus AF36 in or on cotton, gin byproducts; cotton, hulls; cotton, meal;...

  7. 21 CFR 173.120 - Carbohydrase and cellulase derived from Aspergillus niger.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Carbohydrase and cellulase derived from Aspergillus... cellulase derived from Aspergillus niger. Carbohydrase and cellulase enzyme preparation derived from Aspergillus niger may be safely used in food in accordance with the following prescribed conditions:...

  8. 40 CFR 180.1254 - Aspergillus flavus NRRL 21882; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Aspergillus flavus NRRL 21882... RESIDUES IN FOOD Exemptions From Tolerances § 180.1254 Aspergillus flavus NRRL 21882; exemption from the... of Aspergillus flavus NRRL 21882 on peanut; peanut, hay; peanut, meal; and peanut, refined oil....

  9. Two novel Aspergillus species from hypersaline soils of The National Park of Lake Urmia, Iran

    DEFF Research Database (Denmark)

    Arzanlou, M.; Samadi, R.; Frisvad, Jens Christian;

    2016-01-01

    Two novel Aspergillus species, one belonging to the section Terrei and the other to section Flavipedes, were isolated from hypersaline soils of The National Park of Lake Urmia (Iran) and are here described as Aspergillus iranicus and Aspergillus urmiensis. A polyphasic taxonomic approach comprising...

  10. A G-Protein β Subunit Required for Sexual and Vegetative Development and Maintenance of Normal Gα Protein Levels in Neurospora crassa

    OpenAIRE

    Yang, Qi; Poole, Sheven I.; Borkovich, Katherine A.

    2002-01-01

    The genome of the filamentous fungus Neurospora crassa contains a single gene encoding a heterotrimeric G-protein β subunit, gnb-1. The predicted GNB-1 protein sequence is most identical to Gβ proteins from the filamentous fungi Cryphonectria parasitica and Aspergillus nidulans. N. crassa GNB-1 is also 65% identical to the human GNB-1 protein but only 38 and 45% identical to Gβ proteins from budding and fission yeasts. Previous studies in animal and fungal systems have elucidated phenotypes o...

  11. Aspergillus Mediastinitis after Orthotopic Heart Transplantation: A Case Report.

    Science.gov (United States)

    El-Sayed Ahmed, Magdy M; Almanfi, Abdelkader; Aftab, Muhammad; Singh, Steve K; Mallidi, Hari R; Frazier, O H

    2015-10-01

    A 55-year-old woman was admitted for orthotopic heart transplantation. Her medical history was notable for multiple cardiovascular problems, including ischemic cardiomyopathy that necessitated circulatory support with a left ventricular assist device. Five weeks after undergoing orthotopic heart transplantation, she developed Aspergillus calidoustus mediastinitis, for which she underwent a prolonged course of antifungal treatment that comprised (in sequence) posaconazole for 11 days, voriconazole for 10 days, and amphotericin B for 42 days. During this period, she also underwent repeated mediastinal drainage and sternal débridement, followed by sternal wiring and coverage with bilateral pectoralis advancement flaps. Four months postoperatively, she was discharged from the hospital with a successfully controlled infection and a healed sternum. To our knowledge, only 3 previous cases of Aspergillus mediastinitis after orthotopic heart transplantation have been reported in the literature, none of which was Aspergillus calidoustus.

  12. Heterologous expression of Aspergillus terreus fructosyltransferase in Kluyveromyces lactis.

    Science.gov (United States)

    Spohner, Sebastian C; Czermak, Peter

    2016-06-25

    Fructo-oligosaccharides are prebiotic and hypocaloric sweeteners that are usually extracted from chicory. They can also be produced from sucrose using fructosyltransferases, but the only commercial enzyme suitable for this purpose is Pectinex Ultra, which is produced with Aspergillus aculeatus. Here we used the yeast Kluyveromyces lactis to express a secreted recombinant fructosyltransferase from the inulin-producing fungus Aspergillus terreus. A synthetic codon-optimised version of the putative β-fructofuranosidase ATEG 04996 (XP 001214174.1) from A. terreus NIH2624 was secreted as a functional protein into the extracellular medium. At 60°C, the purified A. terreus enzyme generated the same pattern of oligosaccharides as Pectinex Ultra, but at lower temperatures it also produced oligomers with up to seven units. We achieved activities of up to 986.4U/mL in high-level expression experiments, which is better than previous reports of optimised Aspergillus spp. fermentations. PMID:27084521

  13. Phosphate solubilizing ability of two Arctic Aspergillus niger strains

    Directory of Open Access Journals (Sweden)

    Shiv Mohan Singh,

    2011-06-01

    Full Text Available Many filamentous fungi were isolated from the soils of Ny-Ålesund, Spitsbergen, Svalbard, and were screened in vitro for their phosphate solubilizing ability. Two strains of Aspergillus niger showed good tricalcium phosphate (TCP solubilizing ability in Pikovskaya's medium. The TCP solubilization index was calculated at varying levels of pH and temperatures. The ability of Aspergillus niger strain-1 to solubilize and release inorganic-P was 285 µg ml–1, while Aspergillus niger strain-2 solubilized 262 µg ml–1 from 0.5% TCP after seven days. This is the first report of TCP solubilization by Arctic strains that may serve as very good phosphate solubilizers in the form of biofertilizer.

  14. Variability in Galactomannan detection by platelia Aspergillus EIA™ according to the Aspergillus species Variabilidade na detecção de galactomanana pelo Platelia Aspergillus EIA® de acordo com a espécie de Aspergillus

    Directory of Open Access Journals (Sweden)

    Melissa Orzechowski Xavier

    2013-06-01

    Full Text Available Here we investigate the extent to which different Aspergillus species release galactomannan (GM in vitro. Marked variability was observed in GM reactivity between and within Aspergillus species, with A. terreus strains showing the highest GM indexes. The in vivo significance of these findings remains to be determined.O estudo objetivou investigar a liberação in vitro de galactomanana (GM em distintas espécies patogênicas de fungos do gênero Aspergillus. Grande variabilidade foi detectada tanto intra quanto inter espécies, sendo as cepas da espécie A. terreus relacionadas aos maiores índices de GM detectados. O significado in vivo destes achados permanece em aberto, porém merece investigação.

  15. Biosorption potency of Aspergillus niger for removal of chromium (VI).

    Science.gov (United States)

    Srivastava, Shaili; Thakur, Indu Shekhar

    2006-09-01

    Aspergillus niger isolated from soil and effluent of leather tanning mills had higher activity to remove chromium. The potency of Aspergillus niger was evaluated in shake flask culture by absorption of chromium at pH 6 and temperature 30 degrees C. The results of the study indicated removal of more than 75% chromium by Aspergillus niger determined by diphenylcarbazide colorimetric assay and atomic absorption spectrophotometry after 7 days. Study of microbial Cr(VI) reduction and identification of reduction intermediates has been hindered by the lack of analytical techniques that can identify the oxidation state with subcellular spatial resolution. Therefore, removal of chromium was further substantiated by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX), which indicated an accumulation of chromium in the fungal mycelium. PMID:16874547

  16. Electrochemical monitoring of citric acid production by Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Kutyła-Olesiuk, Anna; Wawrzyniak, Urszula E.; Ciosek, Patrycja; Wróblewski, Wojciech, E-mail: wuwu@ch.pw.edu.pl

    2014-05-01

    Highlights: • Citric acid fermentation process (production) by Aspergillus niger. • Qualitative/quantitative monitoring of standard culture and culture infected with yeast. • Electronic tongue based on potentiometric and voltammetric sensors. • Evaluation of the progress and the correctness of the fermentation process. • The highest classification abilities of the hybrid electronic tongue. - Abstract: Hybrid electronic tongue was developed for the monitoring of citric acid production by Aspergillus niger. The system based on various potentiometric/voltammetric sensors and appropriate chemometric techniques provided correct qualitative and quantitative classification of the samples collected during standard Aspergillus niger culture and culture infected with yeast. The performance of the proposed approach was compared with the monitoring of the fermentation process carried out using classical methods. The results obtained proved, that the designed hybrid electronic tongue was able to evaluate the progress and correctness of the fermentation process.

  17. Aspergillus sellar abscess: Case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Hao Li

    2008-01-01

    Full Text Available Aspergillus sellar abscess is a very rare form of fungal infections of the central nervous system (CNS. In this report, we describe the successful treatment of a patient with aspergillus sellar abscess. A 65-year-old woman presented with headache, nasal discharge and decreased visual acuity. The diagnosis of sellar mass was made on the basis of magnetic resonance imaging (MRI examination. The computed tomography (CT scan revealed sellar enlargement and sellar floor bony destruction. After hospitalization the patient underwent transsphenoidal surgery. Histopathological examination of the sellar mass revealed aspergillosis. Postoperatively, amphotericine-B and itraconazole therapy was started. During a six-month follow-up, the patient′s headache and inertia disappeared, visual acuity improved. Aspergillus sellar abscess must be considered in the differential diagnosis of a sellar mass. The correct diagnosis of pituitary aspergillosis can only be achieved by histopathological examination. Surgical intervention and antifungal therapy should be considered the optimal treatment.

  18. Transcriptomic profiling of Aspergillus flavus in response to 5-azacytidine.

    Science.gov (United States)

    Lin, Jian-Qing; Zhao, Xi-Xi; Zhi, Qing-Qing; Zhao, Ming; He, Zhu-Mei

    2013-07-01

    Aspergillus flavus is a common saprophyte and opportunistic pathogen producing aflatoxin (AF) and many other secondary metabolites. 5-Azacytidine (5-AC), a derivative of the nucleoside cytidine, is widely used for studies in epigenetics and cancer biology as an inactivator of DNA methyltransferase and is also used for studying secondary metabolism in fungi. Our previous studies showed that 5-AC affects development and inhibits AF production in A. flavus, and that A. flavus lacks DNA methylation. In this study, an RNA-Seq approach was applied to explore the mechanism of 5-AC's effect on A. flavus. We identified 240 significantly differentially expressed (Q-value<0.05) genes after 5-AC treatment, including two backbone genes respectively in secondary metabolite clusters #27 and #35. These two clusters are involved in development or survival of sclerotia. GO functional enrichment analysis showed that these significantly differentially expressed genes were mainly involved in catalytic activity and proteolytic functions. The expressed transcripts of most genes in the AF biosynthetic gene cluster in A. flavus showed no significant changes after treatment with 5-AC and were expressed at low levels, and the transcription regulator genes aflR and aflS in this cluster did not show differential expression relative to the sample without 5-AC treatment. We found that the veA gene, which encodes protein bridges VelB and LaeA, decreased profoundly the expressed transcripts, and brlA, which encodes an early regulator of development, increased its transcripts in A. flavus after 5-AC treatment. Our data support a model whereby 5-AC affects development through increasing the expression of brlA by depressing the expression of veA and AF production through suppressing veA expression and dysregulating carboxypeptidase activity, which then prevents the aflatoxisomes (vesicles) from performing their normal function in AF formation. Furthermore, the suppressed veA expression weakens or

  19. Genomics of peanut leaf-spot pathogens; and RNA-interference-mediated control of aflatoxins

    Science.gov (United States)

    An overview update of the research done at USDA-ARS National Peanut Research Laboratory will be presented: including: the release of the Cercospora arachidicola genome, sequencing of Cercosporidium personatum, a workflow to study genetic diversity of aflatoxigenic Aspergillus, and progress on the us...

  20. Electrochemical monitoring of citric acid production by Aspergillus niger.

    Science.gov (United States)

    Kutyła-Olesiuk, Anna; Wawrzyniak, Urszula E; Ciosek, Patrycja; Wróblewski, Wojciech

    2014-05-01

    Hybrid electronic tongue was developed for the monitoring of citric acid production by Aspergillus niger. The system based on various potentiometric/voltammetric sensors and appropriate chemometric techniques provided correct qualitative and quantitative classification of the samples collected during standard Aspergillus niger culture and culture infected with yeast. The performance of the proposed approach was compared with the monitoring of the fermentation process carried out using classical methods. The results obtained proved, that the designed hybrid electronic tongue was able to evaluate the progress and correctness of the fermentation process.

  1. Malic acid production from thin stillage by Aspergillus species.

    Science.gov (United States)

    West, Thomas P

    2011-12-01

    The ability of Aspergillus strains to utilize thin stillage to produce malic acid was compared. The highest malic acid was produced by Aspergillus niger ATCC 9142 at 17 g l(-1). Biomass production from thin stillage was similar with all strains but ATCC 10577 was the highest at 19 g l(-1). The highest malic acid yield (0.8 g g(-1)) was with A. niger ATCC 9142 and ATCC 10577 on the stillage. Thus, thin stillage has the potential to act as a substrate for the commercial production of food-grade malic acid by the A. niger strains.

  2. Impact Of Aspergillus Fungi On Germination Of Chilli Seeds And Its Control

    Directory of Open Access Journals (Sweden)

    Tharsika Ratnarajah

    2015-05-01

    Full Text Available Abstract Chilli fruits are commonly contaminated by Eurotimycetes fungus Aspergillus sp. Eurotiales Trichomaceae. This fungus produced white to lime green mycelium yellowish to green conidia which size is around 340.8amp61549. This study was carried out to investigate the effect of Aspergillus sp. on chilli seed germination. The seeds of the chilli variety MI green were obtained from DATC Jaffna for using this experiment. Chilli seeds were treated with Aspergillus sp. Trichoderma viride Aspergillus sp. Trichoderma viride Aspergillus sp. Neem extract and distilled water as control. Highest germination percentage were observed in T5 suspension of T.viride as 73 followed by 65 germination from T1 distilled water 44 from T3 suspension of Aspergillus sp. and T.viride then T4 suspension of Aspergillus sp. and neem leaf extract and T2 suspension of Aspergillus sp. showed the germination as 30 and 20 respectively. The growth inhibition percentage of Aspergillus sp. in presence of T. viride and T. harzianum were calculated by dual culture over control. The percent inhibition of radial growth of Aspergillus sp. was 55.35 by T. viride and 50.25 by T .harzianum in seven days after inoculation. Results show that T.viride was superior to T.harzianum in restricting the growth of Aspergillus sp. on dual culture in PDA.

  3. Antifungal Effects of Thyme, Agastache and Satureja Essential Oils on Aspergillus fumigatus, Aspergillus flavus and Fusarium solani

    Directory of Open Access Journals (Sweden)

    Karim Mardani

    2010-09-01

    Full Text Available Growth inhibition of Aspergillus fumigatus,Aspergillus flavus and Fusarum solani exposed to the essential oils including Thyme, Agastache and Satureja were studied. Disc Diffusion Method was used to evaluate the fungal growth inhibitory effects of the essential oils. Minimal inhibitory concentration (MIC and minimal fungicidal concentration (MFC of the oils were determined and compared with each other. The results showed that all three essential oils examined, had antifungal effects against three fungi species. The MIC data revealed that Thyme oil was the most effective essential oil with the MIC of 62.5 μl ml-1.

  4. Bola fúngica por Aspergillus fumigatus em cavidade pleural Aspergillus fumigatus fungus ball in the pleural cavity

    OpenAIRE

    Luciana Silva Guazzelli; Cecília Bittencourt Severo; Leonardo Santos Hoff; Geison Leonardo Fernandes Pinto; José Jesus Camargo; Luiz Carlos Severo

    2012-01-01

    OBJETIVO: Relatar os casos de 6 pacientes com bola fúngica (BF) na cavidade pleural por Aspergillus fumigatus. MÉTODOS: Entre 1980 e 2009, foram diagnosticados 391 pacientes com BF aspergilar no Complexo Hospitalar Santa Casa de Porto Alegre (RS). O diagnóstico de BF na cavidade pleural foi definido com exames de imagem demonstrando derrame e espessamento pleural com nível líquido; exame micológico direto demonstrando hifas septadas, consistentes com Aspergillus sp.; e cultura positiva para A...

  5. Analysis of Fructanohydrolase System in Aspergillus ficuum%Aspergillus ficuum产果聚糖酶体系的分析

    Institute of Scientific and Technical Information of China (English)

    王静; 金征宇

    2002-01-01

    采用活性聚丙烯酰胺凝胶电泳法对Aspergillus ficuum产果聚糖酶体系进行了分离,获得8条谱带;进一步运用薄层色谱(TLC)和高效液相色谱(HPLC)法进行分析,发现8条谱带中有3条属于外切菊粉酶,2条属于内切菊粉酶,证明了Aspergillus ficuum能同时产内切菊粉酶和外切菊粉酶.

  6. Aminopeptidase C of Aspergillus niger is a Novel Phenylalanine Aminopeptidase

    NARCIS (Netherlands)

    Basten, E.J.W.; Dekker, P.J.T.; Schaap, P.J.

    2003-01-01

    A novel enzyme with a specific phenylalanine aminopeptidase activity (ApsC) from Aspergillus niger (CBS 120.49) has been characterized. The derived amino acid sequence is not similar to any previously characterized aminopeptidase sequence but does share similarity with some mammalian acyl-peptide hy

  7. Biotransformation of quinazoline and phthalazine by Aspergillus niger.

    Science.gov (United States)

    Sutherland, John B; Heinze, Thomas M; Schnackenberg, Laura K; Freeman, James P; Williams, Anna J

    2011-03-01

    Cultures of Aspergillus niger NRRL-599 in fluid Sabouraud medium were grown with quinazoline and phthalazine for 7 days. Metabolites were purified by high-performance liquid chromatography and identified by mass spectrometry and proton nuclear magnetic resonance spectroscopy. Quinazoline was oxidized to 4-quinazolinone and 2,4-quinazolinedione, and phthalazine was oxidized to 1-phthalazinone.

  8. Taxonomy, chemodiversity, and chemoconsistency of Aspergillus, Penicillium, and Talaromyces species

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian

    2015-01-01

    Aspergillus, Penicillium, and Talaromyces are among the most chemically inventive of all fungi, producing a wide array of secondary metabolites (exometabolites). The three genera are holophyletic in a cladistic sense and polythetic classes in an anagenetic or functional sense, and contain 344, 35......, and ochratoxins, in different combinations....

  9. Molecular analysis of endo-rhamnogalacturonan hydrolases in Aspergillus.

    NARCIS (Netherlands)

    ten Hoor-Suykerbuyk, M.E.G.

    1997-01-01

    Bij de enzymatische bereiding van appelsap spelen pectinolytische enzymen en met nar-ne de enzymen die inwerken op de 'hairy regions' van pectine (MHR), een belangrijke rot. Schimmels zijn belangrijke enzym-producenten en een aantal Aspergillus soorten worden veelvuldig gebruikt in de voedingsmiddel

  10. The role of opsonins in Aspergillus fumigatus host defense

    NARCIS (Netherlands)

    Braem, S.G.E.

    2015-01-01

    Aspergillus fumigatus is an important fungal pathogen and a common cause of invasive fungal infections in humans. Susceptible individuals become infected via the inhalation of dormant conidia.If the immune system fails to clear these conidia, they will swell, germinate and grow into large hyphal str

  11. The maize rachis affects Aspergillus flavus movement during ear development

    Science.gov (United States)

    Aspergillus flavus expressing green fluorescent protein (GFP) was used to follow infection in ears of maize hybrids resistant and susceptible to the fungus. Developing ears were needle-inoculated with GFP-transformed A. flavus 20 days after silk emergence, and GFP fluorescence in the pith was evalu...

  12. Accessory enzymes from Aspergillus involved in xylan and pectin degradation

    NARCIS (Netherlands)

    Vries, de R.P.

    1999-01-01

    The xylanolytic and pectinolytic enzyme systems from Aspergillus have been the subject of study for many years. Although the main chain cleaving enzymes and their encoding genes have been studied in detail, little information is available about most of the accessory enzymes and their corresponding g

  13. Cryptic Sexuality Influences Aflatoxigenicity in Aspergillus parasiticus and A. flavus

    Science.gov (United States)

    Ascomycetous fungi of the genus Aspergillus comprise a wide variety of species of biotechnological importance as well as pathogens and toxin producers. Recent studies report A. fumigatus to be heterothallic and possibly undergoing sexual reproduction. We therefore investigated whether compatible mat...

  14. Studies on the production of fungal peroxidases in Aspergillus niger

    NARCIS (Netherlands)

    Conesa, A.; Hondel, C.A.M.J.J. van den; Punt, P.J.

    2000-01-01

    To get insight into the limiting factors existing for the efficient production of fungal peroxidase in filamentous fungi, the expression of the Phanerochaete chrysosporium lignin peroxidase H8 (lipA) and manganese peroxidase (MnP) H4 (mnp1) genes in Aspergillus niger has been studied. For this purpo

  15. Enhanced citrate production through gene insertion in Aspergillus niger

    DEFF Research Database (Denmark)

    Jongh, Wian de; Nielsen, Jens

    2007-01-01

    The effect of inserting genes involved in the reductive branch of the tricarboxylic acid (TCA) cycle on citrate production by Aspergillus niger was evaluated. Several different genes were inserted individually and in combination, i.e. malate dehydrogenase (mdh2) from Saccharomyces cerevisiae, two...

  16. Field ecology, fungal sex and food contamination involving Aspergillus species

    Science.gov (United States)

    Several species within the genus Aspergillus are capable of producing a myriad of toxic secondary metabolites, with aflatoxin being of most concern. These fungi happen to colonize important agricultural commodities, thereby having the potential to contaminate our food with carcinogenic aflatoxins. P...

  17. QUANTITATIVE PCR OF SELECTED ASPERGILLUS, PENICILLIUM AND PAECILOMYCES SPECIES

    Science.gov (United States)

    A total of 65 quantitative PCR (QPCR) assays, incorporating fluorigenic 5' nuclease (TaqMan®) chemistry and directed at the nuclear ribosomal RNA operon, internal transcribed spacer regions (ITS1 or ITS2) was developed and tested for the detection of Aspergillus, Penicillium and ...

  18. Efficient production of Arthromyces ramosus peroxidase by Aspergillus awamori

    NARCIS (Netherlands)

    Lokman, B.C.; Joosten, V.; Hovenkamp, J.; Gouka, R.J.; Verrips, C.T.; Hondel, C.A.M.J.J. van den

    2003-01-01

    The heterologous production of Arthromyces ramosus peroxidase (ARP) was analysed in the filamentous fungus Aspergillus awamori under control of the inducible endoxylanase promoter. Secretion of active ARP was achieved up to 800 mg l-1 in shake flask cultures. Western blot analysis showed that an rAR

  19. Novofumigatonin, a New Orthoester Meroterpenoid from Aspergillus novofumigatus

    DEFF Research Database (Denmark)

    Rank, Christian; Phipps, Richard Kerry; Harris, Pernille;

    2008-01-01

    Novofumigatonin (1), a new metabolite, has been isolated from Aspergillus novofumigatus. The structure and relative stereochemistry were determined from HR ESI MS, one- and two-dimensional NMR, and single-crystal X-ray analysis. The absolute configuration was assigned using vibrational circular...

  20. Dynamics of dsRNA mycoviruses in black Aspergillus population.

    NARCIS (Netherlands)

    Diepeningen, van A.D.; Debets, A.J.M.; Hoekstra, R.F.

    2006-01-01

    Approximately 10% of all examined 668 representatives of black Aspergillus species, independent of worldwide location, were infected with double-stranded RNA (dsRNA) mycoviruses. These isometric viruses (25-40 nm diameter) contained a variety of often multiple segments of different dsRNA sizes rangi

  1. epi-Aszonalenins A, B, and C from Aspergillus novofumigatus

    DEFF Research Database (Denmark)

    Rank, Christian; Phipps, Richard Kerry; Harris, Pernille;

    2006-01-01

    Three new benzodiazepines have been isolated from an unusual chemotype of Aspergillus novofumigatus: epi-aszonalenins A, B, and C. The structures were elucidated by use of one- and two-dimensional NMR spectroscopic techniques and HR ESI MS. The relative configuration was established on the basis...

  2. New and revisited species in Aspergillus section Nigri

    DEFF Research Database (Denmark)

    Varga, J.; Frisvad, Jens Christian; Kocsube, S.;

    2011-01-01

    , and two types of indol-alkaloids which have not been structure elucidated. Two other species, A. violaceofuscus and A. acidus, are revalidated based on molecular and extrolite data. Aspergillus violaceofuscus was found to be related to A. japonicus, and produced some of the same interesting indol...

  3. Metabolic control analysis of xylose catabolism in Aspergillus

    NARCIS (Netherlands)

    Prathumpai, W.; Gabelgaard, J.B.; Wanchanthuek, P.; Vondervoort, van de P.J.I.; Groot, de M.J.L.; McIntyre, M.; Nielsen, J.

    2003-01-01

    A kinetic model for xylose catabolism in Aspergillus is proposed. From a thermodynamic analysis it was found that the intermediate xylitol will accumulate during xylose catabolism. Use of the kinetic model allowed metabolic control analysis (MCA) of the xylose catabolic pathway to be carried out, an

  4. Secretome analysis of Aspergillus fumigatus reveals Asp-hemolysin as a major secreted protein.

    Science.gov (United States)

    Wartenberg, Dirk; Lapp, Katrin; Jacobsen, Ilse D; Dahse, Hans-Martin; Kniemeyer, Olaf; Heinekamp, Thorsten; Brakhage, Axel A

    2011-11-01

    Surface-associated and secreted proteins represent primarily exposed components of Aspergillus fumigatus during host infection. Several secreted proteins are known to be involved in defense mechanisms or immune evasion, thus, probably contributing to pathogenicity. Furthermore, several secreted antigens were identified as possible biomarkers for the verification of diseases caused by Aspergillus species. Nevertheless, there is only limited knowledge about the composition of the secretome and about molecular functions of particular proteins. To identify secreted proteins potentially essential for virulence, the core secretome of A. fumigatus grown in minimal medium was determined. Two-dimensional gel electrophoretic separation and subsequent MALDI-TOF-MS/MS analyses resulted in the identification of 64 different proteins. Additionally, secretome analyses of A. fumigatus utilizing elastin, collagen or keratin as main carbon and nitrogen source were performed. Thereby, the alkaline serine protease Alp1 was identified as the most abundant protein and hence presumably represents an important protease during host infection. Interestingly, the Asp-hemolysin (Asp-HS), which belongs to the protein family of aegerolysins and which was often suggested to be involved in fungal virulence, was present in the secretome under all growth conditions tested. In addition, a second, non-secreted protein with an aegerolysin domain annotated as Asp-hemolysin-like (HS-like) protein can be found to be encoded in the genome of A. fumigatus. Generation and analysis of Asp-HS and HS-like deletion strains revealed no differences in phenotype compared to the corresponding wild-type strain. Furthermore, hemolysis and cytotoxicity was not altered in both single-deletion and double-deletion mutants lacking both aegerolysin genes. All mutant strains showed no attenuation in virulence in a mouse infection model for invasive pulmonary aspergillosis. Overall, this study provides a comprehensive

  5. Metabolic activity in dormant conidia of Aspergillus niger and developmental changes during conidial outgrowth.

    Science.gov (United States)

    Novodvorska, Michaela; Stratford, Malcolm; Blythe, Martin J; Wilson, Raymond; Beniston, Richard G; Archer, David B

    2016-09-01

    The early stages of development of Aspergillus niger conidia during outgrowth were explored by combining genome-wide gene expression analysis (RNAseq), proteomics, Warburg manometry and uptake studies. Resting conidia suspended in water were demonstrated for the first time to be metabolically active as low levels of oxygen uptake and the generation of carbon dioxide were detected, suggesting that low-level respiratory metabolism occurs in conidia for maintenance. Upon triggering of spore germination, generation of CO2 increased dramatically. For a short period, which coincided with mobilisation of the intracellular polyol, trehalose, there was no increase in uptake of O2 indicating that trehalose was metabolised by fermentation. Data from genome-wide mRNA profiling showed the presence of transcripts associated with fermentative and respiratory metabolism in resting conidia. Following triggering of conidial outgrowth, there was a clear switch to respiration after 25min, confirmed by cyanide inhibition. No effect of SHAM, salicylhydroxamic acid, on respiration suggests electron flow via cytochrome c oxidase. Glucose entry into spores was not detectable before 1h after triggering germination. The impact of sorbic acid on germination was examined and we showed that it inhibits glucose uptake. O2 uptake was also inhibited, delaying the onset of respiration and extending the period of fermentation. In conclusion, we show that conidia suspended in water are not completely dormant and that conidial outgrowth involves fermentative metabolism that precedes respiration. PMID:27378203

  6. Novel Route for Agmatine Catabolism in Aspergillus niger Involves 4-Guanidinobutyrase.

    Science.gov (United States)

    Kumar, Sunil; Saragadam, Tejaswani; Punekar, Narayan S

    2015-08-15

    Agmatine, a significant polyamine in bacteria and plants, mostly arises from the decarboxylation of arginine. The functional importance of agmatine in fungi is poorly understood. The metabolism of agmatine and related guanidinium group-containing compounds in Aspergillus niger was explored through growth, metabolite, and enzyme studies. The fungus was able to metabolize and grow on l-arginine, agmatine, or 4-guanidinobutyrate as the sole nitrogen source. Whereas arginase defined the only route for arginine catabolism, biochemical and bioinformatics approaches suggested the absence of arginine decarboxylase in A. niger. Efficient utilization by the parent strain and also by its arginase knockout implied an arginase-independent catabolic route for agmatine. Urea and 4-guanidinobutyrate were detected in the spent medium during growth on agmatine. The agmatine-grown A. niger mycelia contained significant levels of amine oxidase, 4-guanidinobutyraldehyde dehydrogenase, 4-guanidinobutyrase (GBase), and succinic semialdehyde dehydrogenase, but no agmatinase activity was detected. Taken together, the results support a novel route for agmatine utilization in A. niger. The catabolism of agmatine by way of 4-guanidinobutyrate to 4-aminobutyrate into the Krebs cycle is the first report of such a pathway in any organism. A. niger GBase peptide fragments were identified by tandem mass spectrometry analysis. The corresponding open reading frame from the A. niger NCIM 565 genome was located and cloned. Subsequent expression of GBase in both Escherichia coli and A. niger along with its disruption in A. niger functionally defined the GBase locus (gbu) in the A. niger genome.

  7. Another two genes controlling mitotic intragenic recombination and recovery from UV damage in Aspergillus nidulans IV. Genetic analysis of mitotic intragenic recombinants from uvs+/uvs+, uvsD/uvsD and uvsE/uvsE diploids

    NARCIS (Netherlands)

    Fortuin, J.J.H.

    1971-01-01

    This paper presents the results of a genetic analysis of a number of spontaneous mitotic p-aminobenzoic acid-independent recombinants from uvs+/uvs+, uvsD53/uvsD53 and uvsE82/uvsE82 diploids that are heteroallelic at the pabaA locus. Intragenic recombination in each of the three strains is largely n

  8. AMINO ACID SUPPLEMENTATION REVEALS DIFFERENTIAL REGULATION OF AFLATOXIN BIOSYNTHESIS IN ASPERGILLUS FLAVUS NRRL 3357 AND ASPERGILLUS PARASITICUS SRRC 143

    Science.gov (United States)

    Aflatoxins are toxic and carcinogenic secondary metabolites produced by the fungi Aspergillus flavus and A. parasiticus. In order to better understand the molecular mechanisms that regulate aflatoxin production, the biosynthesis of the toxin in A. flavus and A. parasiticus grown in yeast extract su...

  9. Tet-on, or Tet-off, that is the question: Advanced conditional gene expression in Aspergillus.

    Science.gov (United States)

    Wanka, Franziska; Cairns, Timothy; Boecker, Simon; Berens, Christian; Happel, Anna; Zheng, Xiaomei; Sun, Jibin; Krappmann, Sven; Meyer, Vera

    2016-04-01

    In Aspergillus, controlled gene expression is often achieved using the reverse tetracycline-controlled transactivator (rtTA) dependent Tet-on system, whereby transcription is activated in a titratable manner by addition of the tetracycline derivative doxycycline. The complementary Tet-off system utilises the tetracycline-controlled transactivator (tTA) component to quantitatively reduce gene expression. In this study, we utilised a synthetic biological approach to engineer highly optimised Tet-off conditional expression systems in Aspergillus niger and Aspergillus fumigatus. Steps for delivery of these tools include utilising codon optimised cassette components, testing several promoters for improved genetic stability and validating two modified luciferase reporters for highly accurate measurements of gene expression. The Tet-off cassettes developed in this study enable facile and quantitative functional analysis, as validated by Tet-off analysis of genes involved in chitin synthesis and cell wall polarity in A. niger, and para-aminobenzoic acid synthesis in A. fumigatus. We also used a racA(G18V) dominant allele to demonstrate that Tet-off in A. niger enables gene over-expression and downregulation in a single isolate. Additionally, we used the improved luciferase reporters to show that the Tet-off cassette in A. niger enables quantification of gene oscillations. In order to demonstrate that synthetic biological approaches developed here are broadly applicable to engineering transcriptional circuits in filamentous fungi, we used our strategy for improving cassette stability by promoter replacement in the A. niger Tet-on system, which resulted in a modified Tet-on cassette with higher stability in recipient genomes. PMID:26555930

  10. Metabolomics Analysis Reveals Specific Novel Tetrapeptide and Potential Anti-Inflammatory Metabolites in Pathogenic Aspergillus species.

    Science.gov (United States)

    Lee, Kim-Chung; Tam, Emily W T; Lo, Ka-Ching; Tsang, Alan K L; Lau, Candy C Y; To, Kelvin K W; Chan, Jasper F W; Lam, Ching-Wan; Yuen, Kwok-Yung; Lau, Susanna K P; Woo, Patrick C Y

    2015-06-17

    Infections related to Aspergillus species have emerged to become an important focus in infectious diseases, as a result of the increasing use of immunosuppressive agents and high fatality associated with invasive aspergillosis. However, laboratory diagnosis of Aspergillus infections remains difficult. In this study, by comparing the metabolomic profiles of the culture supernatants of 30 strains of six pathogenic Aspergillus species (A. fumigatus, A. flavus, A. niger, A. terreus, A. nomius and A. tamarii) and 31 strains of 10 non-Aspergillus fungi, eight compounds present in all strains of the six Aspergillus species but not in any strain of the non-Aspergillus fungi were observed. One of the eight compounds, Leu-Glu-Leu-Glu, is a novel tetrapeptide and represents the first linear tetrapeptide observed in Aspergillus species, which we propose to be named aspergitide. Two other closely related Aspergillus-specific compounds, hydroxy-(sulfooxy)benzoic acid and (sulfooxy)benzoic acid, may possess anti-inflammatory properties, as 2-(sulfooxy)benzoic acid possesses a structure similar to those of aspirin [2-(acetoxy)benzoic acid] and salicylic acid (2-hydroxybenzoic acid). Further studies to examine the potentials of these Aspergillus-specific compounds for laboratory diagnosis of aspergillosis are warranted and further experiments will reveal whether Leu-Glu-Leu-Glu, hydroxy-(sulfooxy)benzoic acid and (sulfooxy)benzoic acid are virulent factors of the pathogenic Aspergillus species.

  11. [Indoor fungal exposure: What impact on clinical and biological status regarding Aspergillus during cystic fibrosis].

    Science.gov (United States)

    Pricope, D; Deneuville, E; Frain, S; Chevrier, S; Belaz, S; Roussey, M; Gangneux, J-P

    2015-06-01

    The sources of exposure during diseases due to Aspergillus fungi in cystic fibrosis patients are still poorly explored. We assessed home fungal exposure in patients suffering from cystic fibrosis and analysed its impact on the presence of Aspergillus biological markers, the colonisation of airways, as well as the sensitization and Aspergillus serology. Between March 2012 and August 2012, 34 patients benefited from a visit performed by a home environment medical adviser including sampling for mycological analysis. The number of colonies of Aspergillus was not significantly different in the various sampling sites (P=0.251), but the number of non-Aspergillus colonies was much higher in the kitchen (P=0.0045). Subsequently, home fungal exposure was compared between the groups "absence of Aspergillus-related markers" and "presence of Aspergillus-related markers". Home exposure to Aspergillus (P=0.453) and non-Aspergillus (P=0.972) flora was not significant between the 2 groups. Within this series of 34 patients that should be expanded, we note an absence of clear relationship between home exposure and the Aspergillus-linked markers in patients suffering from cystic fibrosis. This result should be taken into account regarding too restrictive hygiene advices provided to families, given the fact that fungal exposure can also results from activities performed away from home.

  12. Metabolomics Analysis Reveals Specific Novel Tetrapeptide and Potential Anti-Inflammatory Metabolites in Pathogenic Aspergillus species

    Directory of Open Access Journals (Sweden)

    Kim-Chung Lee

    2015-06-01

    Full Text Available Infections related to Aspergillus species have emerged to become an important focus in infectious diseases, as a result of the increasing use of immunosuppressive agents and high fatality associated with invasive aspergillosis. However, laboratory diagnosis of Aspergillus infections remains difficult. In this study, by comparing the metabolomic profiles of the culture supernatants of 30 strains of six pathogenic Aspergillus species (A. fumigatus, A. flavus, A. niger, A. terreus, A. nomius and A. tamarii and 31 strains of 10 non-Aspergillus fungi, eight compounds present in all strains of the six Aspergillus species but not in any strain of the non-Aspergillus fungi were observed. One of the eight compounds, Leu–Glu–Leu–Glu, is a novel tetrapeptide and represents the first linear tetrapeptide observed in Aspergillus species, which we propose to be named aspergitide. Two other closely related Aspergillus-specific compounds, hydroxy-(sulfooxybenzoic acid and (sulfooxybenzoic acid, may possess anti-inflammatory properties, as 2-(sulfooxybenzoic acid possesses a structure similar to those of aspirin [2-(acetoxybenzoic acid] and salicylic acid (2-hydroxybenzoic acid. Further studies to examine the potentials of these Aspergillus-specific compounds for laboratory diagnosis of aspergillosis are warranted and further experiments will reveal whether Leu–Glu–Leu–Glu, hydroxy-(sulfooxybenzoic acid and (sulfooxybenzoic acid are virulent factors of the pathogenic Aspergillus species.

  13. Clinical Performance of Aspergillus PCR for Testing Serum and Plasma: a Study by the European Aspergillus PCR Initiative.

    Science.gov (United States)

    White, P Lewis; Barnes, Rosemary A; Springer, Jan; Klingspor, Lena; Cuenca-Estrella, Manuel; Morton, C Oliver; Lagrou, Katrien; Bretagne, Stéphane; Melchers, Willem J G; Mengoli, Carlo; Donnelly, J Peter; Heinz, Werner J; Loeffler, Juergen

    2015-09-01

    Aspergillus PCR testing of serum provides technical simplicity but with potentially reduced sensitivity compared to whole-blood testing. With diseases for which screening to exclude disease represents an optimal strategy, sensitivity is paramount. The associated analytical study confirmed that DNA concentrations were greater in plasma than those in serum. The aim of the current investigation was to confirm analytical findings by comparing the performance of Aspergillus PCR testing of plasma and serum in the clinical setting. Standardized Aspergillus PCR was performed on plasma and serum samples concurrently obtained from hematology patients in a multicenter retrospective anonymous case-control study, with cases diagnosed according to European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) consensus definitions (19 proven/probable cases and 42 controls). Clinical performance and clinical utility (time to positivity) were calculated for both kinds of samples. The sensitivity and specificity for Aspergillus PCR when testing serum were 68.4% and 76.2%, respectively, and for plasma, they were 94.7% and 83.3%, respectively. Eighty-five percent of serum and plasma PCR results were concordant. On average, plasma PCR was positive 16.8 days before diagnosis and was the earliest indicator of infection in 13 cases, combined with other biomarkers in five cases. On average, serum PCR was positive 10.8 days before diagnosis and was the earliest indicator of infection in six cases, combined with other biomarkers in three cases. These results confirm the analytical finding that the sensitivity of Aspergillus PCR using plasma is superior to that using serum. PCR positivity occurs earlier when testing plasma and provides sufficient sensitivity for the screening of invasive aspergillosis while maintaining methodological simplicity.

  14. Cancer genomics

    DEFF Research Database (Denmark)

    Norrild, Bodil; Guldberg, Per; Ralfkiær, Elisabeth Methner

    2007-01-01

    Almost all cells in the human body contain a complete copy of the genome with an estimated number of 25,000 genes. The sequences of these genes make up about three percent of the genome and comprise the inherited set of genetic information. The genome also contains information that determines whe...

  15. Segregação mitótica induzida pelo edulcorante L-Aspartil-L-Fenilalanina-Metil-Ester (aspartame em células diplóides de Aspergillus nidulans - DOI: 10.4025/actascibiolsci.v25i1.2121 Mitotic segregation induced by edulcorant l-aspartyl-l-phenylalanine-metyl-ester (aspartame in diploid cells of Aspergillus nidulans - DOI: 10.4025/actascibiolsci.v25i1.2121

    Directory of Open Access Journals (Sweden)

    Marialba Avezum Alves Castro Prado

    2003-04-01

    Full Text Available O presente trabalho demonstra o efeito recombinagênico do edulcorante artificial L-Aspartil-L-Fenilalanina-Metil-Ester (aspartame, amplamente utilizado em dietas hipocalóricas e de baixo consumo de glicose. Este efeito pode refletir respostas celulares a danos genéticos induzidos pelo edulcorante artificial, no período G2 do ciclo celular e demonstra sua capacidade de induzir homozigose de genes recessivos previamente presentes em heterozigoseThis study aims to verify the recombinogenic effect of artificial edulcorant l-aspartil-l-phenylalanine-metyl-ester (aspartame, widely used in hypocaloric and low-glucose diets. Such effect may reflect cell response to genetic damage, induced by artificial edulcorant in the cell cycle G2 period and shows its capacity to induce homozygosis of recessive genes, previously present in heterozygosis

  16. Characterization of a polyketide synthase in Aspergillus niger whose product is a precursor for both dihydroxynaphthalene (DHN) melanin and naphtho-γ-pyrone.

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Yi Ming; Meyer, Kristen M; Praseuth, Michael; Baker, Scott E; Bruno, Kenneth S; Wang, Clay C

    2010-12-06

    The genome sequencing of the fungus Aspergillus niger, an industrial workhorse, uncovered a large cache of genes encoding enzymes thought to be involved in the production of secondary metabolites yet to be identified. Identification and structural characterization of many of these predicted secondary metabolites are hampered by their low concentration relative to the known A. niger metabolites such as the naphtho-γ-pyrone family of polyketides. We deleted a nonreducing PKS gene in A. niger strain ATCC 11414, a daughter strain of A. niger ATCC strain 1015 whose genome was sequenced by the DOE Joint Genome Institute. This PKS encoding gene is a predicted ortholog of alb1 from Aspergillus fumigatus which is responsible for production of YWA1, a precursor of fungal DHN melanin. Our results show that the A. niger alb1 PKS is responsible for the production of the polyketide precursor for DHN melanin biosynthesis. Deletion of alb1 elimnates the production of major metabolites, naphtho-γ-pyrones. The generation of an A. niger strain devoid of naphtho-γ-pyrones will greatly facilitate the elucidation of cryptic biosynthetic pathways in this organism.

  17. Purification and characterization of a glutaminase enzyme accounting for the majority of glutaminase activity in Aspergillus sojae under solid-state culture.

    Science.gov (United States)

    Ito, Kotaro; Hanya, Yoshiki; Koyama, Yasuji

    2013-10-01

    Glutaminase, an enzyme that hydrolyzes L-glutamine to L-glutamate, plays an important role in the production of fermented foods by enhancing the umami taste. In this study, we found ten glutaminase genes in the Aspergillus sojae genome by conducting a BLAST search of the characterized glutaminase sequence. We subsequently constructed glutaminase gene disruptants. The glutaminase activity of the gahB disruptant was decreased by approximately 90 % in A. sojae and Aspergillus oryzae, indicating that this enzyme (GahB) accounted for the majority of the glutaminase activity in Aspergillus species. Subsequently, GahB protein was purified from the AsgahB-overexpressing transformant and characterized. The molecular mass was estimated to be approximately 110 and 259 kDa by SDS-PAGE and gel filtration chromatography, respectively, indicating that the native form of AsGahB was a dimer. The optimal pH was 9.0, and the optimal temperature was 50 °C. Analysis of substrate specificity revealed that AsGahB had peptidoglutaminase-asparaginase activity, similar to AsGahA, but preferred free L-glutamine to free L-asparagine, C-terminal glutaminyl, and asparaginyl residues in peptides.

  18. Transcriptional regulation of chemical diversity in Aspergillus fumigatus by LaeA.

    Directory of Open Access Journals (Sweden)

    Robyn M Perrin

    2007-04-01

    Full Text Available Secondary metabolites, including toxins and melanins, have been implicated as virulence attributes in invasive aspergillosis. Although not definitively proved, this supposition is supported by the decreased virulence of an Aspergillus fumigatus strain, DeltalaeA, that is crippled in the production of numerous secondary metabolites. However, loss of a single LaeA-regulated toxin, gliotoxin, did not recapitulate the hypovirulent DeltalaeA pathotype, thus implicating other toxins whose production is governed by LaeA. Toward this end, a whole-genome comparison of the transcriptional profile of wild-type, DeltalaeA, and complemented control strains showed that genes in 13 of 22 secondary metabolite gene clusters, including several A. fumigatus-specific mycotoxin clusters, were expressed at significantly lower levels in the DeltalaeA mutant. LaeA influences the expression of at least 9.5% of the genome (943 of 9,626 genes in A. fumigatus but positively controls expression of 20% to 40% of major classes of secondary metabolite biosynthesis genes such as nonribosomal peptide synthetases (NRPSs, polyketide synthases, and P450 monooxygenases. Tight regulation of NRPS-encoding genes was highlighted by quantitative real-time reverse-transcription PCR analysis. In addition, expression of a putative siderophore biosynthesis NRPS (NRPS2/sidE was greatly reduced in the DeltalaeA mutant in comparison to controls under inducing iron-deficient conditions. Comparative genomic analysis showed that A. fumigatus secondary metabolite gene clusters constitute evolutionarily diverse regions that may be important for niche adaptation and virulence attributes. Our findings suggest that LaeA is a novel target for comprehensive modification of chemical diversity and pathogenicity.

  19. Research on Real-Time Quantitative PCR Technology of Common Aspergillus Species%常见曲霉菌的实时定量PCR诊断技术的研究

    Institute of Scientific and Technical Information of China (English)

    武学成; 龚文胜

    2012-01-01

    Objective The detected method of real-time quantitative PCR technology on common Aspergillus Species was developed. Methods The employing universal, fungus-specific primers and DNA probes, directed to the conservative internal transcribed spacer 2(ITS2) region of ribosomal DNA from A, terreus, A flavus, A. Fumigatus, A. Terreus, A. Nidulans and A niger were designed. Five kinds of common Aspergillus Species were detected by the quantitative real-time PCR and common PCR technology. Results DNA from each Aspergillus species for which DNA probes were designed produced am-plicons of approximately 350bp in size. Melting temperature of A, terreus, A. Flavus, A. Fumigatus,A terreus, A. Nidulajis and A. Niger was respectively 57℃ ± 0. 12℃ , 59℃ ± 0. 13℃ , 63℃ ± 0. 17℃ , 66°C ± 0. 15℃ , 66℃ ± 0. 14℃ and 68℃± 0. 12°C by melting peak analysis for five different Aspergillus spp. The minimum reaction concentration of DNA response template of A terreus, A flavus, A fumigatus, A nidulans and A niger was respectively 82. 4, 621. 3, 51. 2, 520. 8 and 19. 5 fg/μl by sensitivity analysis of common Aspergillus species. Conclusion The developed technology of real-time quantitative PCR is simple, rapid, and sensitive for the identification of medically important common Aspergillus species, which was a new option in invasive aspergillosis diagnosis.%目的 建立常见曲霉菌的实时定量PCR诊断技术.方法 针对黄曲霉菌、烟曲霉菌、构巢曲霉菌、黑曲霉菌和土曲霉菌内转录间隔区2(internal transcribed spacer 2,ITS2)保守基因设计引物和探针,通过普通PCR扩增其ITS2基因片段,作为实时定量PCR反应模板,通过实时定量扩增和分析其解链曲线来鉴定常见曲霉菌,同时分析该方法灵敏度.结果 真菌通用引物扩增五种常见曲霉菌ITS2基因DNA片段,大小为350 bp左右.实时定量PCR分析和探针解链曲线分析结果显示土曲霉解链温度(melting temperature

  20. Expression of an alpha-galactosidase from Saccharomyces cerevisiae in Aspergillus awamori and Aspergillus oryzae.

    Science.gov (United States)

    Murphy, R A; Power, R F G

    2002-02-01

    A gene encoding alpha-galactosidase activity was isolated by polymerase chain reaction (PCR) from Saccharomyces cerevisiae NCYC686 and separately placed under the control of transcriptional elements regulating alpha-amylase expression in Aspergillus oryzae and glucoamylase expression in A. awamori. Following transformation of both A. oryzae and A. awamori with their respective expression vectors, induction of heterologous alpha-galactosidase from positively selected clones was effected through the addition of soluble starch (10% wt/vol) to the growth medium. Upon induction in A. oryzae, a transcriptional instability resulted in degradation of mRNA encoding heterologous alpha-galactosidase, thus preventing expression of the active enzyme. The use of a gene fusion strategy in A. awamori overcame this instability and resulted in stable expression of S. cerevisiae alpha-galactosidase. Subsequent to initial (shake flask) experiments, a series of scale-up and optimisation studies led to heterologous expression of the recombinant enzyme in batch fermentation at 51 U mg(-1) total extracellular protein. This was higher than previously published works, which reported extracellular levels of heterologous alpha-galactosidase up to 38 U mg(-1) total protein. Analysis of crude extracts of the fermentation medium revealed significant differences between the activity parameters reported previously in the literature for this enzyme and those observed here. The recombinant enzyme exhibited thermostability properties not previously reported for S. cerevisiae alpha-galactosidase, a trait which would make it suitable for use in processes requiring high temperatures. PMID:12074058

  1. Enhanced aflatoxin production by aspergillus parasiticus and aspergillus flavus after low dose gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hitoshi (Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment)

    1992-09-01

    Spores of Aspergillus parasiticus IFO 30179 and A. flavus var. columnaris S46 were irradiated at 0.05, 0.2 and 0.4 kGy in the synthetic low salts (SL) broth, and the effect on aflatoxin production was examined after 10 days incubation at 30 or 25degC. In these two strains, irradiation of spores at 0.05 kGy resulted in higher B1 or G1 production than the non-irradiated controles. However, spores of the both strains irradiated at 0.2 or 0.4 kGy produced less aflatoxins than non-irradiated controles. In the SL broth, apparent stimulation by low dose irradiation was slight, and these enhanced effects were not observed after reinfection to fresh SL broth. In the case of food samples, the levels of aflatoxin B[sub 1] and G[sub 1] with A. parasiticus were increased from 15 to 90% by incubation of irradiated spores at 1 kGy in autoclaved polished rice, black pepper, white pepper and red pepper. These enhancement would be induced by change of composition in each substrates. Mutations of fungi induced by irradiation is not effective for enhancement of aflatoxin production. (author).

  2. Cadmium biosorption by Aspergillus niger; Biossorcao de cadmio pelo Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Silva, E.P.; Barros Junior, L.M.; Duarte, M.M.L.; Macedo, G.R. [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil)]. E-mail: edmilson@eq.ufrn.br

    2003-07-01

    Biosorption is a property of certain types of inactive, dead, microbial biomass to bind and concentrate heavy metals from even very dilute aqueous solutions. Biomass exhibits this property, acting just as a chemical substance, as an ion exchanger of biological origin. It is particularly the cell wall structure of certain algae, fungi and bacteria which was found responsible for this phenomenon. Some of the biomass types come as a waste by-product of large-scale industrial fermentations (the mold Rhizopus or the bacterium Bacillus subtilis). Other metal-binding biomass types, certain abundant seaweeds (particularly brown algae e.g. Sargassum, Ecklonia), can be readily collected from the oceans. These biomass types, serving as a basis for metal biosorption processes, can accumulate in excess of 25% of their dry weight in deposited heavy metals: Pb, Cd, U, Cu, Zn, even Cr and others. Sorption experiments using the Aspergillus niger fungus for cadmium removal were carried out to study the factors influencing and optimizing the biosorption of this metal. The effects of pH, time, biomass concentration, and initial concentration of the heavy metal on the rate of metallic biosorption were examined. (author)

  3. Evaluation of antifungal activity of essential oils against potentially mycotoxigenic Aspergillus flavus and Aspergillus parasiticus

    Directory of Open Access Journals (Sweden)

    Fernanda C. da Silva

    2012-10-01

    Full Text Available The antifungal activity of essential oils of fennel (Foeniculum vulgare Mill., Apiaceae, ginger (Zingiber officinale Roscoe, Zingiberaceae, mint (Mentha piperita L., Lamiaceae and thyme (Thymus vulgaris L., Lamiaceae was evaluated against mycotoxin producers Aspergillus flavus and A. parasiticus. High Resolution Gas Chromatography was applied to analyze chemical constituents of essential oils. The effect of different concentrations of essential oils was determined by solid medium diffusion assay. Mycelial growth and sporulation were determined for each essential oil at the concentrations established by solid medium diffusion assay. At the fifth, seventh and ninth days the mycelial diameter (Ø mm and spore production were also determined. FUN-1 staining was performed to assess cell viability after broth macrodilution assay. Trans-anethole, zingiberene, menthol and thymol are the major component of essential oils of fennel, ginger, mint and thyme, respectively. The effective concentrations for fennel, ginger, mint and thyme were 50, 80, 50 and 50% (oil/DMSO; v/v, respectively. The four essential oils analysed in this study showed antifungal effect. Additionally, FUN-1 staining showed to be a suitable method to evaluate cell viability of potential mycotoxigenic fungi A. flavus and A. parasiticus after treatment with essential oils.

  4. Peanut gene expression profiling in developing seeds at different reproduction stages during Aspergillus parasiticus infection

    Directory of Open Access Journals (Sweden)

    Liang Xuanqiang

    2008-02-01

    Full Text Available Abstract Background Peanut (Arachis hypogaea L. is an important crop economically and nutritionally, and is one of the most susceptible host crops to colonization of Aspergillus parasiticus and subsequent aflatoxin contamination. Knowledge from molecular genetic studies could help to devise strategies in alleviating this problem; however, few peanut DNA sequences are available in the public database. In order to understand the molecular basis of host resistance to aflatoxin contamination, a large-scale project was conducted to generate expressed sequence tags (ESTs from developing seeds to identify resistance-related genes involved in defense response against Aspergillus infection and subsequent aflatoxin contamination. Results We constructed six different cDNA libraries derived from developing peanut seeds at three reproduction stages (R5, R6 and R7 from a resistant and a susceptible cultivated peanut genotypes, 'Tifrunner' (susceptible to Aspergillus infection with higher aflatoxin contamination and resistant to TSWV and 'GT-C20' (resistant to Aspergillus with reduced aflatoxin contamination and susceptible to TSWV. The developing peanut seed tissues were challenged by A. parasiticus and drought stress in the field. A total of 24,192 randomly selected cDNA clones from six libraries were sequenced. After removing vector sequences and quality trimming, 21,777 high-quality EST sequences were generated. Sequence clustering and assembling resulted in 8,689 unique EST sequences with 1,741 tentative consensus EST sequences (TCs and 6,948 singleton ESTs. Functional classification was performed according to MIPS functional catalogue criteria. The unique EST sequences were divided into twenty-two categories. A similarity search against the non-redundant protein database available from NCBI indicated that 84.78% of total ESTs showed significant similarity to known proteins, of which 165 genes had been previously reported in peanuts. There were

  5. Invasive aspergillosis in the aortic arch with infectious Aspergillus lesions in pulmonary bullae

    Directory of Open Access Journals (Sweden)

    Isao Watanabe

    2015-03-01

    Full Text Available A patient with pulmonary bullae died of massive hemoptysis. At autopsy a hole was observed in the aortic wall. A microscopic examination indicated small Aspergillus lesions in pulmonary bullae and extensive necrotic lesions with Aspergillus hyphae in the media of the thoracic aorta. These findings led to a diagnosis of invasive aspergillosis in the aortic arch. This is a rare case in which Aspergillus invaded the aorta in a patient without hematologic neoplasms or neutropenia.

  6. Immunosuppressive Compounds Exhibit Particular Effects on Functional Properties of Human Anti-Aspergillus TH1 Cells

    OpenAIRE

    Tramsen, Lars; Schmidt, Stanislaw; Roeger, Frauke; Schubert, Ralf; Salzmann-Manrique, Emilia; Latgé, Jean-Paul; Klingebiel, Thomas; Lehrnbecher, Thomas

    2014-01-01

    Allogeneic hematopoietic stem cell transplant (HSCT) recipients are at high risk for invasive aspergillosis. Whereas adoptive immunotherapy transferring donor-derived anti-Aspergillus TH1 cells has been shown to be beneficial for HSCT recipients suffering from invasive aspergillosis, little is known about the impact of commonly used immunosuppressants on the functional properties of anti-Aspergillus TH1 cells. Anti-Aspergillus TH1 cells were coincubated with different concentrations of methyl...

  7. Aspergillus as a multi-purpose cell factory: current status and perspectives

    OpenAIRE

    2010-01-01

    Abstract Aspergilli have a long history in biotechnology as expression platforms for the production of food ingredients, pharmaceuticals and enzymes. The achievements made during the last years, however, have the potential to revolutionize Aspergillus biotechnology and to assure Aspergillus a dominant place among microbial cell factories. This mini-review will highlight most recent breakthroughs in fundamental and applied Aspergillus research with a focus on new molecular tools, te...

  8. New ochratoxin A producing species of Aspergillus section Circumdati

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Frank, J.M.; Houbraken, J.A.M.P.;

    2004-01-01

    Aspergillus section Circumdati contains species with yellow to ochre conidia and non-black sclerotia that produce at least one of the following extrolites: ochratoxins, penicillic acids, xanthomegnins or melleins. The exception to this is A. robustus, which produces black sclerotia, phototropic...... are described here, A. cretensis, A. flocculosus, A. neobridgeri, A. pseudoelegans, A. roseoglobulosus, A. steynii, and A. westerdijkiae. Twelve species of section Circumdati produce mellein, 17 produce penicillic acid and 17 produce xanthomegnins. Eight species consistently produce large amounts of ochratoxin...... A: Aspergillus cretensis, A. flocculosus, A. pseudoelegans, A. roseoglobulosus, A. westerdijkiae, A. sulphurous, and Neopetromyces muricatus. Two species produce large or small amounts of ochratoxin A, but less consistently: A. ochraceus and A. sclerotiorum. Ochratoxin production in these species...

  9. Primary cutaneous aspergillosis due to Aspergillus flavus: a case report

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qiang-qiang; LI Li; ZHU Min; ZHANG Chao-ying; WANG Jia-jun

    2005-01-01

    @@ Infections caused by opportunistic organisms which have been known as etiologic agents of disease become more and more frequent.Aspergillus spp. is one of the agents. Fungi of aspergillus genus are widely distributed in nature, particularly in the soil and in the decomposed vegetation. They are frequent opportunist pathogens in immunocompromised patients. The most frequent causative organisms that cause cutaneous aspergillosis are A.fumigatus and A.flavus.1-3 In this report, we present a case of primary cutaneous aspergillosis manifested by ulceration of the shank due to A. flavus. The patient had no deficiency of immunological status and severe disease associated with fungal infection. Excellent response was shown to anti-fungal therapy.

  10. Biosorption of Cadmium by Fungal Biomass of Aspergillus niger

    Institute of Scientific and Technical Information of China (English)

    QI YANG; JIAN-LONG WANG; ZHI XING

    2005-01-01

    Objective To investigate the removal of cadmium from aqueous solution by waste fungal biomass of Aspergillus niger, originated from citric acid fermentation industry. Methods Batch adsorption test was used to study the biosorption equilibrium and isotherm. The Cd2+ concentration was measured with atomic adsorption spectrophotometer (AAS) HITACHI 180-80. Results The biosorption achieved equilibrium within 30 min. The adsorption isotherm could be described by Freundlich adsorption model, and the constants KF and 1/n were determined to be 2.07 and 0.18, respectively, and the correlation efficiency was 0.97. The optimal pH for Cd adsorption was 6.0. The cadmium-laden biomass could be effectively regenerated using 0.1 N HCl. Conclusion The waste biomass of Aspergillus niger, a by-product of fermentation industry, is a potential biosorbent for the removal of cadmium from aqueous solution.

  11. Decolorization of Direct Black 22 by Aspergillus ficuum

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The decolorization of Direct Black 22 by Aspergillus ficuum has been studied. It was found that Aspergillus ficuum could effectively decolorize Direct Black 22 especially when grown as pelleted mycelia. Results showed that the media containing Direct Black 22 at 50 mg/L could be decolorized by 98.05% of the initial color in 24 h. The optimum pH and temperature of decolorization are 4.0 and 33 ℃ respectively. Aeration was quite beneficial to decolorization. Medium composition and the concentration of Direct Black 22 could affect the rate of decolorization. The dye degraded products assayed by UV-visible spectrophotometer and macroscopic observation showed that the decolorization of Direct Black 22 by mycelial pellets includes two important processes: bioadsorption and biodegradation.The degradation experiment agree with the Michaelis-Menten kinetics equation

  12. Biosorption of cadmium using the fungus Aspergillus niger

    OpenAIRE

    Barros Júnior L.M.; Macedo G.R.; Duarte M.M.L.; Silva E.P.; Lobato A.K.C.L.

    2003-01-01

    Sorption experiments using the Aspergillus niger fungus for cadmium removal were carried out to study the factors influencing and optimizing the biosorption of this metal. The effects of pH, time, biomass concentration, and initial concentration of the heavy metal on the rate of metallic biosorption were examined. An experimental design was also used to determine the values of the under study variables that provided the greatest biosorption efficiency. A technique for biomass recovery was als...

  13. Fructooligosaccharides production using immobilized cells of Aspergillus japonicus

    OpenAIRE

    Mussatto, Solange I.; Dragone, Giuliano; Rodrigues, L. R.; Teixeira, J. A.

    2008-01-01

    The fructooligosaccharides (FOS) production using immobilized cells of the fungus Aspergillus japonicus ATCC 20236 was evaluated. Polyurethane foam, stainless steel sponge, vegetal fiber sponge, pumice stones, zeolites and cork were tested as immobilization carrier during the fermentation under submerged conditions. Experiments were carried out in 500 ml Erlenmeyer flasks containing 1 g of carrier and 100 ml of sucrose medium (165 g/l) enriched with nutrient sources. The flasks...

  14. Central nervous system aspergillus infection complicating renal transplantation

    International Nuclear Information System (INIS)

    A case of catastrophic intracerebral haemorrhage secondary to aspergillus infection in an immunocompromised renal transplant patient is presented. The pathological features and related images are described and the radiology of CNS aspergillus infection is reviewed. A 37-year-old woman was admitted with abdominal pain. She had recently received a cadaveric renal transplant following failure of the previous live donor kidney. Gastroscopy showed changes suspicious of cytomegalovirus (CMV) gastroduodenitis and she was treated with gancyclovir, with resolution of her symptoms. While in hospital her creatinine began to rise. The renal biopsy was suggestive of cyclosporin toxicity and the cyclosporin level was raised 537 mg/mL (normal 160-360 mg/mL). Several days later, she developed slurred speech and weakness in her right arm. Non-contrast CT showed multifocal regions of low attenuation over the right temporal convexity, within the basal ganglia, inferior frontal lobe and corona radiata on the left side. Magnetic resonance imaging on the same day showed multiple areas of high signal on the FLAIR images, some of which contained central areas of low signal. There was no significant enhancement post gadolinium but several of the lesions showed increased signal on the diffusion-weighted images, reflecting cytotoxic oedema. Repeat CT showed an increase in the size of the cerebral lesions with haemorrhagic transformation of the right basal ganglia mass. A further lesion with a peripheral dense rim on the non-contrast images was identified in the right cerebellar hemisphere. The possibility of a vasculitis secondary to a fungal infection was raised. Two days later the patient became comatose with CT showing a large intracerebral haematoma in the left basal ganglia, intraventricular blood and hydrocephalus. The patient died soon afterwards. Post-mortem examination showed multifocal cerebral haemorrhage associated with necrotizing vasculitis and aspergillus infection

  15. Four Novel Hydropyranoindeno- Derivatives from Marine Fungus Aspergillus versicolor

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    From the cultured filtrates of fungus Aspergillus versicolor,isolated from marine sponge Xestospongia exigua,four novel secondary metabolites,namely aspergillone 1,aspergillodiol 2, aspergillol 3 and 12-acetyl-aspergillol 4,have been isolated by column chromatographic separation.The structures of all the new compounds are established on the basis of extensive 2D NMR spectroscopy in conjugation with MS,UV spectral analysis.The basic structure pattern of those compounds possessed an hydroindenoisopyran nucleus.

  16. A rare pigmented keratitis caused by Aspergillus fumigatus

    Institute of Scientific and Technical Information of China (English)

    Mauricio; Vélez; Kepa; Balparda; Ana; María; Díaz

    2015-01-01

    <正>Dear Sir,I am Mauricio Vélez,from the Department of Ophthalmology,Cornea Service Director,Universidad Pontificia Bolivariana in Medellín,Colombia.Below,I would like to share an interesting case I managed recently,which I’ve entitled"A rare pigmented keratitis caused by Aspergillus fumigatus".Fungi are a relatively uncommon cause of microbial keratitis

  17. Voriconazole for the treatment of refractory Aspergillus fumigatus keratitis

    OpenAIRE

    Mehta, Hijab; Mehta, Hitendra B; Garg, Prashant; Kodial, Harish

    2008-01-01

    We report a case of Aspergillus fumigatus keratitis in a 53-year-old, well-controlled diabetic female who did not respond to standard antifungal treatment. She was started on topical natamycin eye drops, but the infiltrate continued to progress. Topical amphotericin B and systemic ketoconazole was added, however, there was no response and the infiltrate increased further. She was then switched to topical and systemic voriconazole. Steady resolution of the infiltrate was noted within 2 weeks o...

  18. Voriconazole for the treatment of refractory Aspergillus fumigatus keratitis

    Directory of Open Access Journals (Sweden)

    Mehta Hijab

    2008-01-01

    Full Text Available We report a case of Aspergillus fumigatus keratitis in a 53-year-old, well-controlled diabetic female who did not respond to standard antifungal treatment. She was started on topical natamycin eye drops, but the infiltrate continued to progress. Topical amphotericin B and systemic ketoconazole was added, however, there was no response and the infiltrate increased further. She was then switched to topical and systemic voriconazole. Steady resolution of the infiltrate was noted within 2 weeks of therapy.

  19. Raw starch conversion by Saccharomyces cerevisiae expressing Aspergillus tubingensis amylases

    OpenAIRE

    Viktor, Marko J; Rose, Shaunita H.; van Zyl, Willem H; Viljoen-Bloom, Marinda

    2013-01-01

    Background Starch is one of the most abundant organic polysaccharides available for the production of bio-ethanol as an alternative transport fuel. Cost-effective utilisation of starch requires consolidated bioprocessing (CBP) where a single microorganism can produce the enzymes required for hydrolysis of starch, and also convert the glucose monomers to ethanol. Results The Aspergillus tubingensis T8.4 α-amylase (amyA) and glucoamylase (glaA) genes were cloned and expressed in the laboratory ...

  20. Biotransformation of steviol derivatives by Aspergillus niger and Fusarium moniliforme

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Bras H. de; Leal, Paulo C. [Parana Univ., Curitiba, PR (Brazil). Dept. de Quimica]. E-mail: bho@ufpr.br; Souza Filho, Jose Dias [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Quimica

    2005-04-01

    Steviol derivatives have been submitted to biotransformations by fungi. Methyl ent-11{beta},13-dihydroxy-15,16-epoxikauran-19-oate was hydroxylated at C-11 by Aspergillus niger, whereas ent-16{beta}-hydroxybeyeran-19-oic acid was hydroxylated at C-6 and C-7 by Fusarium moniliforme. The hydroxylation at non-activated positions at the carbon skeleton is discussed in connection with the properties of important polyhydroxylated diterpenoids described in the literature. (author)