WorldWideScience

Sample records for fungal b-lactam biosynthesis

  1. Fungal biosynthesis of gold nanoparticles: mechanism and scale up.

    Science.gov (United States)

    Kitching, Michael; Ramani, Meghana; Marsili, Enrico

    2015-11-01

    Gold nanoparticles (AuNPs) are a widespread research tool because of their oxidation resistance, biocompatibility and stability. Chemical methods for AuNP synthesis often produce toxic residues that raise environmental concern. On the other hand, the biological synthesis of AuNPs in viable microorganisms and their cell-free extracts is an environmentally friendly and low-cost process. In general, fungi tolerate higher metal concentrations than bacteria and secrete abundant extracellular redox proteins to reduce soluble metal ions to their insoluble form and eventually to nanocrystals. Fungi harbour untapped biological diversity and may provide novel metal reductases for metal detoxification and bioreduction. A thorough understanding of the biosynthetic mechanism of AuNPs in fungi is needed to reduce the time of biosynthesis and to scale up the AuNP production process. In this review, we describe the known mechanisms for AuNP biosynthesis in viable fungi and fungal protein extracts and discuss the most suitable bioreactors for industrial AuNP biosynthesis. © 2014 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  2. Structure and biosynthesis of fungal alpha-glucans

    NARCIS (Netherlands)

    Grün, Christian Hugo

    2003-01-01

    The fungal cell wall is unique among eukaryotes and therefore it forms an ideal target for the development of novel antifungal drugs. Fungal cell morphology and integrity depend on a cell-surrounding wall, which is composed of glycoproteins and polysaccharides. Disrupting enzymes that are involved

  3. Reconstitution of a fungal meroterpenoid biosynthesis reveals the involvement of a novel family of terpene cyclases

    Science.gov (United States)

    Itoh, Takayuki; Tokunaga, Kinya; Matsuda, Yudai; Fujii, Isao; Abe, Ikuro; Ebizuka, Yutaka; Kushiro, Tetsuo

    2010-10-01

    Meroterpenoids are hybrid natural products of both terpenoid and polyketide origin. We identified a biosynthetic gene cluster that is responsible for the production of the meroterpenoid pyripyropene in the fungus Aspergillus fumigatus through reconstituted biosynthesis of up to five steps in a heterologous fungal expression system. The cluster revealed a previously unknown terpene cyclase with an unusual sequence and protein primary structure. The wide occurrence of this sequence in other meroterpenoid and indole-diterpene biosynthetic gene clusters indicates the involvement of these enzymes in the biosynthesis of various terpenoid-bearing metabolites produced by fungi and bacteria. In addition, a novel polyketide synthase that incorporated nicotinyl-CoA as the starter unit and a prenyltransferase, similar to that in ubiquinone biosynthesis, was found to be involved in the pyripyropene biosynthesis. The successful production of a pyripyropene analogue illustrates the catalytic versatility of these enzymes for the production of novel analogues with useful biological activities.

  4. Exploring the fungal protein cadre in the biosynthesis of PbSe quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, Jaya Mary; Sharma, Sumit; Balakrishnan, Raj Mohan, E-mail: rajmohanbala@gmail.com

    2017-02-15

    Highlights: • Pb and Se stress activates specific metal detoxification surge in the fungus. • Fungus releases phytochelatins, metallothioneins, super oxide dismutases etc. • These mechanisms capacitate the fungi as bio-factories for synthesis of PbSe QDs. • A pathway for PbSe QD biosynthesis by marine Aspergillus terreus was elucidated - Abstract: While a large number of microbial sources have recently emerged as potent sources for biosynthesis of chalcogenide quantum dots (QDs), studies regarding their biomimetic strategies that initiate QD biosynthesis are scarce. The present study describes several mechanistic aspects of PbSe QD biosynthesis using marine Aspergillus terreus. Scanning electron microscopic (SEM) studies indicated distinctive morphological features such as abrasion and agglomeration on the fungal biomass after the biosynthesis reaction. Further, the biomass subsequent to the heavy metal/metalloid precursor was characterized with spectral signatures typical to primary and secondary stress factors such as thiol compounds and oxalic acid using Fourier Transform Infra-Red Spectroscopic (FTIR) analysis. An increase in the total protein content in the reaction mixture after biosynthesis was another noteworthy observation. Further, metal-phytochelatins were identified as the prominent metal-ion trafficking components in the reaction mixture using Liquid Chromatography Mass Spectroscopic analysis (LCMS). Subsequent assays confirmed the involvement of metal binding peptides namely metallothioneins and other anti-oxidant enzymes that might have played a prominent role in the microbial metal detoxification system for the biosynthesis of PbSe QDs. Based on these findings a possible mechanism for the biosynthesis of PbSe QDs by marine A. terreus has been elucidated.

  5. Biosynthesis of the fungal cell wall polysaccharide galactomannan requires intraluminal GDP-mannose.

    Science.gov (United States)

    Engel, Jakob; Schmalhorst, Philipp S; Routier, Françoise H

    2012-12-28

    Fungal cell walls frequently contain a polymer of mannose and galactose called galactomannan. In the pathogenic filamentous fungus Aspergillus fumigatus, this polysaccharide is made of a linear mannan backbone with side chains of galactofuran and is anchored to the plasma membrane via a glycosylphosphatidylinositol or is covalently linked to the cell wall. To date, the biosynthesis and significance of this polysaccharide are unknown. The present data demonstrate that deletion of the Golgi UDP-galactofuranose transporter GlfB or the GDP-mannose transporter GmtA leads to the absence of galactofuran or galactomannan, respectively. This indicates that the biosynthesis of galactomannan probably occurs in the lumen of the Golgi apparatus and thus contrasts with the biosynthesis of other fungal cell wall polysaccharides studied to date that takes place at the plasma membrane. Transglycosylation of galactomannan from the membrane to the cell wall is hypothesized because both the cell wall-bound and membrane-bound polysaccharide forms are affected in the generated mutants. Considering the severe growth defect of the A. fumigatus GmtA-deficient mutant, proving this paradigm might provide new targets for antifungal therapy.

  6. The Cell Wall of the Human Fungal Pathogen Aspergillus fumigatus: Biosynthesis, Organization, Immune Response, and Virulence.

    Science.gov (United States)

    Latgé, Jean-Paul; Beauvais, Anne; Chamilos, Georgios

    2017-09-08

    More than 90% of the cell wall of the filamentous fungus Aspergillus fumigatus comprises polysaccharides. Biosynthesis of the cell wall polysaccharides is under the control of three types of enzymes: transmembrane synthases, which are anchored to the plasma membrane and use nucleotide sugars as substrates, and cell wall-associated transglycosidases and glycosyl hydrolases, which are responsible for remodeling the de novo synthesized polysaccharides and establishing the three-dimensional structure of the cell wall. For years, the cell wall was considered an inert exoskeleton of the fungal cell. The cell wall is now recognized as a living organelle, since the composition and cellular localization of the different constitutive cell wall components (especially of the outer layers) vary when the fungus senses changes in the external environment. The cell wall plays a major role during infection. The recognition of the fungal cell wall by the host is essential in the initiation of the immune response. The interactions between the different pattern-recognition receptors (PRRs) and cell wall pathogen-associated molecular patterns (PAMPs) orientate the host response toward either fungal death or growth, which would then lead to disease development. Understanding the molecular determinants of the interplay between the cell wall and host immunity is fundamental to combatting Aspergillus diseases.

  7. AmcA - a putative mitochondrial ornithine transporter supporting fungal siderophore biosynthesis

    Directory of Open Access Journals (Sweden)

    Lukas eSchafferer

    2015-04-01

    Full Text Available Iron is an essential nutrient required for a wide range of cellular processes. The opportunistic fungal pathogen Aspergillus fumigatus employs low-molecular mass iron-specific chelators, termed siderophores, for uptake, storage and intracellular iron distribution, which play a crucial role in the pathogenicity of this fungus. Siderophore biosynthesis depends on coordination with the supply of its precursor ornithine, produced mitochondrially from glutamate or cytosolically via hydrolysis of arginine. In this study, we demonstrate a role of the putative mitochondrial transporter AmcA (AFUA_8G02760 in siderophore biosynthesis of A. fumigatus.Consistent with a role in cellular ornithine handling, AmcA-deficiency resulted in decreased cellular ornithine and arginine contents as well as decreased siderophore production on medium containing glutamine as the sole nitrogen source. In support, arginine and ornithine as nitrogen sources did not impact siderophore biosynthesis due to cytosolic ornithine availability. As revealed by Northern blot analysis, transcript levels of siderophore biosynthetic genes were unresponsive to the cellular ornithine level. In contrast to siderophore production, AmcA deficiency did only mildly decrease the cellular polyamine content, demonstrating cellular prioritization of ornithine use. Nevertheless, AmcA-deficiency increased the susceptibility of A. fumigatus to the polyamine biosynthesis inhibitor eflornithine, most likely due to the decreased ornithine pool. AmcA-deficiency decreased the growth rate particularly on ornithine as the sole nitrogen source during iron starvation and sufficiency, indicating an additional role in the metabolism and fitness of A. fumigatus, possibly in mitochondrial ornithine import. In the Galleria mellonella infection model, AmcA-deficiency did not affect virulence of A. fumigatus, most likely due to the residual siderophore production and arginine availability in this host niche.

  8. Induction of sesquiterpenoid biosynthesis in tobacco cell suspension cultures by fungal elicitor

    International Nuclear Information System (INIS)

    Chappell, J.; Nable, R.

    1987-01-01

    Large amounts of the sesquiterpenoid capsidiol accumulated in the media of tobacco (Nicotiana tabacum L. cv KY14) cell suspension cultures upon addition of fungal elicitor. Capsidiol accumulation was proportional to the amount of elicitor added. The accumulation of capsidiol was preceded by a transient increase in the capsidiol de novo synthesis rate as measured by the incorporation of exogenous [ 14 C]acetate. Changes in 3-hydroxy-3-methylglutaryl-CoA reductase activity, an enzyme of general isoprenoid metabolism, paralleled the changes in [ 14 C]acetate incorporation into capsidiol. Incubation of the cell cultures with mevinolin, a potent in vitro inhibitor of the tobacco HMGR enzyme activity, inhibited the elicitor-induced capsidiol accumulation in a concentration dependent manner. [ 14 C]Acetate incorporation into capsidiol was likewise inhibited by mevinolin treatment. Unexpectedly, [ 3 H] mevalonate incorporation into capsidiol was also partially inhibited by mevinolin, suggesting that mevinolin may effect secondary sites of sesquiterpenoid biosynthesis in vivo beyond HMGR. The data indicated the importance of the induced HMGR activity for capsidiol production in elicitor-treated tobacco cell suspension cultures

  9. Biosynthesis of the major tetrahydroxystilbenes in spruce, astringin and isorhapontin, proceeds via resveratrol and is enhanced by fungal infection.

    Science.gov (United States)

    Hammerbacher, Almuth; Ralph, Steven G; Bohlmann, Joerg; Fenning, Trevor M; Gershenzon, Jonathan; Schmidt, Axel

    2011-10-01

    Stilbenes are dibenzyl polyphenolic compounds produced in several unrelated plant families that appear to protect against various biotic and abiotic stresses. Stilbene biosynthesis has been well described in economically important plants, such as grape (Vitis vinifera), peanut (Arachis hypogaea), and pine (Pinus species). However, very little is known about the biosynthesis and ecological role of stilbenes in spruce (Picea), an important gymnosperm tree genus in temperate and boreal forests. To investigate the biosynthesis of stilbenes in spruce, we identified two similar stilbene synthase (STS) genes in Norway spruce (Picea abies), PaSTS1 and PaSTS2, which had orthologs with high sequence identity in sitka (Picea sitchensis) and white (Picea glauca) spruce. Despite the conservation of STS sequences in these three spruce species, they differed substantially from angiosperm STSs. Several types of in vitro and in vivo assays revealed that the P. abies STSs catalyze the condensation of p-coumaroyl-coenzyme A and three molecules of malonyl-coenzyme A to yield the trihydroxystilbene resveratrol but do not directly form the dominant spruce stilbenes, which are tetrahydroxylated. However, in transgenic Norway spruce overexpressing PaSTS1, significantly higher amounts of the tetrahydroxystilbene glycosides, astringin and isorhapontin, were produced. This result suggests that the first step of stilbene biosynthesis in spruce is the formation of resveratrol, which is further modified by hydroxylation, O-methylation, and O-glucosylation to yield astringin and isorhapontin. Inoculating spruce with fungal mycelium increased STS transcript abundance and tetrahydroxystilbene glycoside production. Extracts from STS-overexpressing lines significantly inhibited fungal growth in vitro compared with extracts from control lines, suggesting that spruce stilbenes have a role in antifungal defense.

  10. Submicrometric Iron Particles for the Removal of Pharmaceuticals from Water: Application to b-Lactam Antibiotics

    International Nuclear Information System (INIS)

    Ghauch, A.; Baydoun, H.; Tuqan, M.; Ayoub, Gh.; Naim, S.

    2011-01-01

    Sub-micrometric iron particles (Fe0) and amended Fe0 (Cu0Fe0) were tested for the aqueous removal of b-lactam antibiotics. Comparative batch experiments were performed separately on aqueous solutions of dicloxacillin (DCX), cloxacillin (CLX) and oxacillin (OXA). Three different initial concentrations (1, 5 and 10 mg L-1) and four different iron loads (r = 10, 20, 40 and 53 g L-1) were tested. Furthermore, two different mixing regimes were tested: (i) non-disturbed conditions, and (ii) vortex mixing. This experimental design enabled the confirmation of the crucial role of in-situ formed iron corrosion products (Fe oxides) on the removal process. The dynamic process of Fe oxides formation induces adsorption and enmeshment (sequestration or co-precipitation) of dissolved antibiotics. Results clearly delineated the superiority of Cu0Fe0 bimetallics compared to Fe0. For example, after 4 h of contact with iron particles at r = 40 g L-1, OXA, CLX and DCX (10 mg L-1 each) disappeared to an extent of 31, 46 and 71%. However, quantitative antibiotic removal (∼ 90%) was noticed when Cu0Fe0 bimetallic was used at lesser load (r = 20 g L-1) under vortex mixing. On the other hand, non-disturbed systems showed partial removal (∼ 25%) of antibiotics over 7 h of reaction at r = 10 g L-1 (Fe0) while almost complete removals were noticed for the Cu0Fe0 bimetallic system for the same metal load and period e.g. 75, 79 and 86% removal for OXA, CLX and DCX respectively. (author)

  11. Ergothioneine Biosynthesis and Functionality in the Opportunistic Fungal Pathogen, Aspergillus fumigatus.

    Science.gov (United States)

    Sheridan, Kevin J; Lechner, Beatrix Elisabeth; Keeffe, Grainne O'; Keller, Markus A; Werner, Ernst R; Lindner, Herbert; Jones, Gary W; Haas, Hubertus; Doyle, Sean

    2016-10-17

    Ergothioneine (EGT; 2-mercaptohistidine trimethylbetaine) is a trimethylated and sulphurised histidine derivative which exhibits antioxidant properties. Here we report that deletion of Aspergillus fumigatus egtA (AFUA_2G15650), which encodes a trimodular enzyme, abrogated EGT biosynthesis in this opportunistic pathogen. EGT biosynthetic deficiency in A. fumigatus significantly reduced resistance to elevated H 2 O 2 and menadione, respectively, impaired gliotoxin production and resulted in attenuated conidiation. Quantitative proteomic analysis revealed substantial proteomic remodelling in ΔegtA compared to wild-type under both basal and ROS conditions, whereby the abundance of 290 proteins was altered. Specifically, the reciprocal differential abundance of cystathionine γ-synthase and β-lyase, respectively, influenced cystathionine availability to effect EGT biosynthesis. A combined deficiency in EGT biosynthesis and the oxidative stress response regulator Yap1, which led to extreme oxidative stress susceptibility, decreased resistance to heavy metals and production of the extracellular siderophore triacetylfusarinine C and increased accumulation of the intracellular siderophore ferricrocin. EGT dissipated H 2 O 2 in vitro, and elevated intracellular GSH levels accompanied abrogation of EGT biosynthesis. EGT deficiency only decreased resistance to high H 2 O 2 levels which suggests functionality as an auxiliary antioxidant, required for growth at elevated oxidative stress conditions. Combined, these data reveal new interactions between cellular redox homeostasis, secondary metabolism and metal ion homeostasis.

  12. Genomic and metabolic characterisation of alkaloid biosynthesis by asexual Epichloë fungal endophytes of tall fescue pasture grasses.

    Science.gov (United States)

    Ekanayake, Piyumi N; Kaur, Jatinder; Tian, Pei; Rochfort, Simone J; Guthridge, Kathryn M; Sawbridge, Timothy I; Spangenberg, German C; Forster, John W

    2017-06-01

    Symbiotic associations between tall fescue grasses and asexual Epichloë fungal endophytes exhibit biosynthesis of alkaloid compounds causing both beneficial and detrimental effects. Candidate novel endophytes with favourable chemotypic profiles have been identified in germplasm collections by screening for genetic diversity, followed by metabolite profile analysis in endogenous genetic backgrounds. A subset of candidates was subjected to genome survey sequencing to detect the presence or absence and structural status of known genes for biosynthesis of the major alkaloid classes. The capacity to produce specific metabolites was directly predictable from metabolic data. In addition, study of duplicated gene structure in heteroploid genomic constitutions provided further evidence for the origin of such endophytes. Selected strains were inoculated into meristem-derived callus cultures from specific tall fescue genotypes to perform isogenic comparisons of alkaloid profile in different host backgrounds, revealing evidence for host-specific quantitative control of metabolite production, consistent with previous studies. Certain strains were capable of both inoculation and formation of longer-term associations with a nonhost species, perennial ryegrass (Lolium perenne L.). Discovery and primary characterisation of novel endophytes by DNA analysis, followed by confirmatory metabolic studies, offers improvements of speed and efficiency and hence accelerated deployment in pasture grass improvement programs.

  13. Fungal endophytes – the hidden inducers of volatile terpene biosynthesis in tomato plants

    DEFF Research Database (Denmark)

    Ntana, Fani; Jensen, Birgit; Jørgensen, Hans Jørgen Lyngs

    mycorrhizal spores in the Indian Thar desert, colonizes the root cortex of a wide range of plants, enhancing plant growth and modulating plant specialized metabolism. The effect of S. indica colonization on the metabolism of the host can be potentially used in improving plant defence against pathogens...... and herbivores. Tomato (Solanum lycopersicum) is an important crop, often challenged by fungal pathogens and insect pests. The wide variety of secondary metabolites produced by the plant, and especially terpenes, play a crucial role in plant defence, helping in repelling possible enemies. This project is focused....... indica-inoculated and S. indica-free tomato plants. Preliminary data suggest that fungal colonization results in increased production of specific volatile terpenes. A transcriptome analysis on fungus-associated and fungus-free plant tissues is currently ongoing to elucidate in depth the mechanisms...

  14. Engineered fungal polyketide biosynthesis in Pichia pastoris: a potential excellent host for polyketide production.

    Science.gov (United States)

    Gao, Limei; Cai, Menghao; Shen, Wei; Xiao, Siwei; Zhou, Xiangshan; Zhang, Yuanxing

    2013-09-08

    Polyketides are one of the most important classes of secondary metabolites and usually make good drugs. Currently, heterologous production of fungal polyketides for developing a high potential industrial application system with high production capacity and pharmaceutical feasibility was still at its infancy. Pichia pastoris is a highly successful system for the high production of a variety of heterologous proteins. In this work, we aim to develop a P. pastoris based in vivo fungal polyketide production system for first time and evaluate its feasibility for future industrial application. A recombinant P. pastoris GS115-NpgA-ATX with Aspergillus nidulans phosphopantetheinyl transferase (PPtase) gene npgA and Aspergillus terrus 6-methylsalicylic acid (6-MSA) synthase (6-MSAS) gene atX was constructed. A specific compound was isolated and identified as 6-MSA by HPLC, LC-MS and NMR. Transcription of both genes were detected. In 5-L bioreactor, the GS115-NpgA-ATX grew well and produced 6-MSA quickly until reached a high value of 2.2 g/L by methanol induction for 20 hours. Thereafter, the cells turned to death ascribing to high concentration of antimicrobial 6-MSA. The distribution of 6-MSA changed that during early and late induction phase it existed more in supernatant while during intermediate stage it mainly located intracellular. Different from 6-MSA production strain, recombinant M. purpureus pksCT expression strains for citrinin intermediate production, no matter PksCT located in cytoplasm or in peroxisomes, did not produce any specific compound. However, both npgA and pksCT transcripted effectively in cells and western blot analysis proved the expression of PPtase. Then the PPTase was expressed and purified, marked by fluorescent probes, and reacted with purified ACP domain and its mutant ACPm of PksCT. Fluoresence was only observed in ACP but not ACPm, indicating that the PPTase worked well with ACP to make it bioactive holo-ACP. Thus, some other factors may

  15. Design and Investigation of Optical Properties of N-(Rhodamine-B)-Lactam-Ethylenediamine (RhB-EDA) Fluorescent Probe.

    Science.gov (United States)

    Soršak, Eva; Volmajer Valh, Julija; Korent Urek, Špela; Lobnik, Aleksandra

    2018-04-14

    This study presents chemical modification of a Rhodamine B (RhB) sensor probe by ethylenediamine (EDA), and investigation of its spectral as well as sensor properties to the various metals. The synthesised N -(Rhodamine-B)-lactam-ethylenediamine (RhB-EDA) fluorescent probe shows interesting optical sensor properties, and high sensitivity and selectivity to Ag⁺ ions among all the tested metal ions (K⁺, Mg 2+ , Cu 2+ , Ni 2+ , Fe 2+ , Pb 2+ , Na⁺, Mn 2+ , Li⁺, Al 3+ , Co 2+ , Hg 2+ , Sr 2+ , Ca 2+ , Ag⁺, Cd 2+ and Zn 2+ ), while the well-known Rhodamine B (RhB) fluorescent probe shows much less sensitivity to Ag⁺ ions, but high sensitivity to Fe 2+ ions. The novel fluorescent sensor probe RhB-EDA has the capabilities to sense Ag⁺ ions up to µM ranges by using the fluorescence quenching approach. The probe displayed a dynamic response to Ag⁺ in the range of 0.43 × 10 -3 -10 -6 M with a detection limit of 0.1 μM. The sensing system of an RhB-EDA novel fluorescent probe was optimised according to the spectral properties, effect of pH and buffer, photostability, incubation time, sensitivity, and selectivity. Since all the spectral and sensing properties were tested in green aqueous media, although many other similar sensor systems rely on organic solvent solutions, the RhB-EDA sensing probe may be a good candidate for measuring Ag⁺ ions in real-life applications.

  16. Biosynthesis and Characterization of Zearalenone-14-Sulfate, Zearalenone-14-Glucoside and Zearalenone-16-Glucoside Using Common Fungal Strains

    Directory of Open Access Journals (Sweden)

    Antje Borzekowski

    2018-03-01

    Full Text Available Zearalenone (ZEN and its phase II sulfate and glucoside metabolites have been detected in food and feed commodities. After consumption, the conjugates can be hydrolyzed by the human intestinal microbiota leading to liberation of ZEN that implies an underestimation of the true ZEN exposure. To include ZEN conjugates in routine analysis, reliable standards are needed, which are currently not available. Thus, the aim of the present study was to develop a facilitated biosynthesis of ZEN-14-sulfate, ZEN-14-glucoside and ZEN-16-glucoside. A metabolite screening was conducted by adding ZEN to liquid fungi cultures of known ZEN conjugating Aspergillus and Rhizopus strains. Cultivation conditions and ZEN incubation time were varied. All media samples were analyzed for metabolite formation by HPLC-MS/MS. In addition, a consecutive biosynthesis was developed by using Fusarium graminearum for ZEN biosynthesis with subsequent conjugation of the toxin by utilizing Aspergillus and Rhizopus species. ZEN-14-sulfate (yield: 49% is exclusively formed by Aspergillus oryzae. ZEN-14-glucoside (yield: 67% and ZEN-16-glucoside (yield: 39% are formed by Rhizopus oryzae and Rhizopus oligosporus, respectively. Purities of ≥73% ZEN-14-sulfate, ≥82% ZEN-14-glucoside and ≥50% ZEN-16-glucoside were obtained by 1H-NMR. In total, under optimized cultivation conditions, fungi can be easily utilized for a targeted and regioselective synthesis of ZEN conjugates.

  17. Linking secondary metabolites to biosynthesis genes in the fungal endophyte Cyanodermella asteris: The anti-cancer bisanthraquinone skyrin

    DEFF Research Database (Denmark)

    Jahn, Linda; Schafhauser, Thomas; Wibberg, Daniel

    2017-01-01

    Fungal aromatic polyketides display a very diverse and widespread group of natural products. Due to their excellent light absorption properties and widely studied biological activities, they offer numerous application for food, textile and pharmaceutical industry. The biosynthetic pathways...... far and further elucidation of the individual biosynthetic steps is needed to fully exploit the biotechnological and medicinal potential of these compounds. Here, we identified the bisanthraquinone skyrin as the main pigment of the fungus Cyanodermella asteris, an endophyte that has recently been...

  18. CZK3, a MAP kinase kinase kinase homolog in Cercospora zeae-maydis, regulates cercosporin biosynthesis, fungal development, and pathogenesis.

    Science.gov (United States)

    Shim, Won-Bo; Dunkle, Larry D

    2003-09-01

    The fungus Cercospora zeae-maydis causes gray leaf spot of maize and produces cercosporin, a photosensitizing perylenequinone with toxic activity against a broad spectrum of organisms. However, little is known about the biosynthetic pathway or factors that regulate cercosporin production. Analysis of a cDNA subtraction library comprised of genes that are up-regulated during cercosporin synthesis revealed a sequence highly similar to mitogen-activated protein (MAP) kinases in other fungi. Sequencing and conceptual translation of the full-length genomic sequence indicated that the gene, which we designated CZK3, contains a 4,119-bp open reading frame devoid of introns and encodes a 1,373-amino acid sequence that is highly similar to Wis4, a MAP kinase kinase kinase in Schizosaccharomyces pombe. Targeted disruption of CZK3 suppressed expression of genes predicted to participate in cercosporin biosynthesis and abolished cercosporin production. The disrupted mutants grew faster on agar media than the wild type but were deficient in conidiation and elicited only small chlorotic spots on inoculated maize leaves compared with rectangular necrotic lesions incited by the wild type. Complementation of disruptants with the CZK3 open reading frame and flanking sequences restored wild-type levels of conidiation, growth rate, and virulence as well as the ability to produce cercosporin. The results suggest that cercosporin is a virulence factor in C. zeae-maydis during maize pathogenesis, but the pleiotropic effects of CZK3 disruption precluded definitive conclusions.

  19. Biosynthesis of nanoparticles of metals and metalloids by basidiomycetes. Preparation of gold nanoparticles by using purified fungal phenol oxidases.

    Science.gov (United States)

    Vetchinkina, Elena P; Loshchinina, Ekaterina A; Vodolazov, Ilya R; Kursky, Viktor F; Dykman, Lev A; Nikitina, Valentina E

    2017-02-01

    The work shows the ability of cultured Basidiomycetes of different taxonomic groups-Lentinus edodes, Pleurotus ostreatus, Ganoderma lucidum, and Grifola frondosa-to recover gold, silver, selenium, and silicon, to elemental state with nanoparticles formation. It examines the effect of these metal and metalloid compounds on the parameters of growth and accumulation of biomass; the optimal cultivation conditions and concentrations of the studied ion-containing compounds for recovery of nanoparticles have been identified. Using the techniques of transmission electron microscopy, dynamic light scattering, X-ray fluorescence and X-ray phase analysis, the degrees of oxidation of the bioreduced elements, the ζ-potential of colloidal solutions uniformity, size, shape, and location of the nanoparticles in the culture fluid, as well as on the surface and the inside of filamentous hyphae have been determined. The study has found the part played by homogeneous chromatographically pure fungal phenol-oxidizing enzymes (laccases, tyrosinases, and Mn-peroxidases) in the recovery mechanism with formation of electrostatically stabilized colloidal solutions. A hypothetical mechanism of gold(III) reduction from HAuCl 4 to gold(0) by phenol oxidases with gold nanoparticles formation of different shapes and sizes has been introduced.

  20. Proteomic analysis of a mutant of Trichoderma arundinaceum impaired in the trichothecene biosynthesis reveals a systemic function of these compounds in the fungal physiology

    Science.gov (United States)

    Trichothecenes are sesquiterpene mycotoxins produced by several fungal genera including Fusarium, Trichothecium, Myrothecium, Stachybotrys, and Trichoderma. These toxins have attracted great attention because they are frequent contaminants of food and animal feed, and can be easily absorbed by anim...

  1. Green Ultrasound versus Conventional Synthesis and Characterization of Specific Task Pyridinium Ionic Liquid Hydrazones Tethering Fluorinated Counter Anions: Novel Inhibitors of Fungal Ergosterol Biosynthesis

    Directory of Open Access Journals (Sweden)

    Nadjet Rezki

    2017-11-01

    Full Text Available A series of specific task ionic liquids (ILs based on a pyridiniumhydrazone scaffold in combination with hexafluorophosphate (PF6−, tetrafluoroboron (BF4− and/or trifluoroacetate (CF3COO− counter anion, were designed and characterized by IR, NMR and mass spectrometry. The reactions were conducted under both conventional and green ultrasound procedures. The antifungal potential of the synthesized compounds 2–25 was investigated against 40 strains of Candida (four standard and 36 clinical isolates. Minimum inhibitory concentrations (MIC90 of the synthesized compounds were in the range of 62.5–2000 μg/mL for both standard and oral Candida isolates. MIC90 results showed that the synthesized 1-(2-(4-chlorophenyl-2-oxoethyl-4-(2-(4-fluorobenzylidenehydrazinecarbonyl-pyridin-1-ium hexafluorophosphate (11 was found to be most effective, followed by 4-(2-(4-fluorobenzylidenehydrazinecarbonyl-1-(2-(4-nitrophenyl-2-oxoethyl-pyridin-1-ium hexafluorophosphate (14 and 1-(2-ethoxy-2-oxoethyl-4-(2-(4-fluorobenzylidenehydrazinecarbonylpyridin-1-ium hexafluorophosphate (8. All the Candida isolates showed marked sensitivity towards the synthesized compounds. Ergosterol content was drastically reduced by more active synthesized compounds, and agreed well with MIC90 values. Confocal scanning laser microscopy (CLSM results showed that the red colored fluorescent dye enters the test agent treated cells, which confirms cell wall and cell membrane damage. The microscopy results obtained suggested membrane-located targets for the action of these synthesized compounds. It appears that the test compounds might be interacting with ergosterol in the fungal cell membranes, decreasing the membrane ergosterol content and ultimately leading to membrane disruption as visible in confocal results. The present study indicates that these synthesized compounds show significant antifungal activity against Candida which forms the basis to carry out further in vivo experiments

  2. Fungal Meningitis

    Science.gov (United States)

    ... Schedules Preteen & Teen Vaccines Meningococcal Disease Sepsis Fungal Meningitis Language: English Spanish Recommend on Facebook Tweet Share ... the brain or spinal cord. Investigation of Fungal Meningitis, 2012 In September 2012, the Centers for Disease ...

  3. Fungal Endocarditis.

    Science.gov (United States)

    Yuan, Shi-Min

    2016-01-01

    Fungal endocarditis is a rare and fatal condition. The Candida and Aspergillus species are the two most common etiologic fungi found responsible for fungal endocarditis. Fever and changing heart murmur are the most common clinical manifestations. Some patients may have a fever of unknown origin as the onset symptom. The diagnosis of fungal endocarditis is challenging, and diagnosis of prosthetic valve fungal endocarditis is extremely difficult. The optimum antifungal therapy still remains debatable. Treating Candida endocarditis can be difficult because the Candida species can form biofilms on native and prosthetic heart valves. Combined treatment appears superior to monotherapy. Combination of antifungal therapy and surgical debridement might bring about better prognosis.

  4. Heme biosynthesis and its regulation : Toward understanding and improvement of heme biosynthesis in filamentous fungi.

    NARCIS (Netherlands)

    S. de Weert; P.J. Punt; Christien Lokman; C.A. van den Hondel; A.C. Franken; A.F. Ram

    2011-01-01

    Heme biosynthesis in fungal host strains has acquired considerable interest in relation to the production of secreted heme-containing peroxidases. Class II peroxidase enzymes have been suggested as eco-friendly replacements of polluting chemical processes in industry. These peroxidases are naturally

  5. Heme biosynthesis and its regulation: Towards understanding and improvement of heme biosynthesis in filamentous fungi

    NARCIS (Netherlands)

    Franken, A.C.W.; Lokman, B.C.; Ram, A.F.J.; Punt, P.J.; Hondel, C.A.M.J.J. van den; Weert, S. de

    2011-01-01

    Heme biosynthesis in fungal host strains has acquired considerable interest in relation to the production of secreted heme-containing peroxidases. Class II peroxidase enzymes have been suggested as eco-friendly replacements of polluting chemical processes in industry. These peroxidases are naturally

  6. The fungal myosin I is essential for Fusarium toxisome formation

    Science.gov (United States)

    The mycotoxin deoxynivalenol (DON) is the most frequently detected secondary metabolite produced by Fusarium graminearum and other Fusarium spp. To date, relatively few studies have addressed how mycotoxin biosynthesis occurs in fungal cells. Here we found that myosin I governs translation of DON bi...

  7. Phylogenetic distribution of fungal sterols.

    Directory of Open Access Journals (Sweden)

    John D Weete

    Full Text Available BACKGROUND: Ergosterol has been considered the "fungal sterol" for almost 125 years; however, additional sterol data superimposed on a recent molecular phylogeny of kingdom Fungi reveals a different and more complex situation. METHODOLOGY/PRINCIPAL FINDINGS: The interpretation of sterol distribution data in a modern phylogenetic context indicates that there is a clear trend from cholesterol and other Delta(5 sterols in the earliest diverging fungal species to ergosterol in later diverging fungi. There are, however, deviations from this pattern in certain clades. Sterols of the diverse zoosporic and zygosporic forms exhibit structural diversity with cholesterol and 24-ethyl -Delta(5 sterols in zoosporic taxa, and 24-methyl sterols in zygosporic fungi. For example, each of the three monophyletic lineages of zygosporic fungi has distinctive major sterols, ergosterol in Mucorales, 22-dihydroergosterol in Dimargaritales, Harpellales, and Kickxellales (DHK clade, and 24-methyl cholesterol in Entomophthorales. Other departures from ergosterol as the dominant sterol include: 24-ethyl cholesterol in Glomeromycota, 24-ethyl cholest-7-enol and 24-ethyl-cholesta-7,24(28-dienol in rust fungi, brassicasterol in Taphrinales and hypogeous pezizalean species, and cholesterol in Pneumocystis. CONCLUSIONS/SIGNIFICANCE: Five dominant end products of sterol biosynthesis (cholesterol, ergosterol, 24-methyl cholesterol, 24-ethyl cholesterol, brassicasterol, and intermediates in the formation of 24-ethyl cholesterol, are major sterols in 175 species of Fungi. Although most fungi in the most speciose clades have ergosterol as a major sterol, sterols are more varied than currently understood, and their distribution supports certain clades of Fungi in current fungal phylogenies. In addition to the intellectual importance of understanding evolution of sterol synthesis in fungi, there is practical importance because certain antifungal drugs (e.g., azoles target reactions in

  8. Targeting iron acquisition blocks infection with the fungal pathogens Aspergillus fumigatus and Fusarium oxysporum.

    Science.gov (United States)

    Leal, Sixto M; Roy, Sanhita; Vareechon, Chairut; Carrion, Steven deJesus; Clark, Heather; Lopez-Berges, Manuel S; Di Pietro, Antonio; diPietro, Antonio; Schrettl, Marcus; Beckmann, Nicola; Redl, Bernhard; Haas, Hubertus; Pearlman, Eric

    2013-01-01

    Filamentous fungi are an important cause of pulmonary and systemic morbidity and mortality, and also cause corneal blindness and visual impairment worldwide. Utilizing in vitro neutrophil killing assays and a model of fungal infection of the cornea, we demonstrated that Dectin-1 dependent IL-6 production regulates expression of iron chelators, heme and siderophore binding proteins and hepcidin in infected mice. In addition, we show that human neutrophils synthesize lipocalin-1, which sequesters fungal siderophores, and that topical lipocalin-1 or lactoferrin restricts fungal growth in vivo. Conversely, we show that exogenous iron or the xenosiderophore deferroxamine enhances fungal growth in infected mice. By examining mutant Aspergillus and Fusarium strains, we found that fungal transcriptional responses to low iron levels and extracellular siderophores are essential for fungal growth during infection. Further, we showed that targeting fungal iron acquisition or siderophore biosynthesis by topical application of iron chelators or statins reduces fungal growth in the cornea by 60% and that dual therapy with the iron chelator deferiprone and statins further restricts fungal growth by 75%. Together, these studies identify specific host iron-chelating and fungal iron-acquisition mediators that regulate fungal growth, and demonstrate that therapeutic inhibition of fungal iron acquisition can be utilized to treat topical fungal infections.

  9. Targeting iron acquisition blocks infection with the fungal pathogens Aspergillus fumigatus and Fusarium oxysporum.

    Directory of Open Access Journals (Sweden)

    Sixto M Leal

    Full Text Available Filamentous fungi are an important cause of pulmonary and systemic morbidity and mortality, and also cause corneal blindness and visual impairment worldwide. Utilizing in vitro neutrophil killing assays and a model of fungal infection of the cornea, we demonstrated that Dectin-1 dependent IL-6 production regulates expression of iron chelators, heme and siderophore binding proteins and hepcidin in infected mice. In addition, we show that human neutrophils synthesize lipocalin-1, which sequesters fungal siderophores, and that topical lipocalin-1 or lactoferrin restricts fungal growth in vivo. Conversely, we show that exogenous iron or the xenosiderophore deferroxamine enhances fungal growth in infected mice. By examining mutant Aspergillus and Fusarium strains, we found that fungal transcriptional responses to low iron levels and extracellular siderophores are essential for fungal growth during infection. Further, we showed that targeting fungal iron acquisition or siderophore biosynthesis by topical application of iron chelators or statins reduces fungal growth in the cornea by 60% and that dual therapy with the iron chelator deferiprone and statins further restricts fungal growth by 75%. Together, these studies identify specific host iron-chelating and fungal iron-acquisition mediators that regulate fungal growth, and demonstrate that therapeutic inhibition of fungal iron acquisition can be utilized to treat topical fungal infections.

  10. Inhibition of Fungal Aflatoxin B1 Biosynthesis by Diverse Botanically ...

    African Journals Online (AJOL)

    School of Food Science, Henan Institute of Science and Technology, Xinxiang 453003, China ... As a globally-consumed beverage, tea contains ..... 19. U.S. Department of Agriculture, Agricultural Research. Service. 2011. USDA Database for the Flavonoid. Content of Selected Foods, Release 3.0. Nutrient. Data Laboratory ...

  11. Freshwater Fungal Infections

    Directory of Open Access Journals (Sweden)

    Dennis J. Baumgardner

    2017-01-01

    Full Text Available Fungal infections as a result of freshwater exposure or trauma are fortunately rare. Etiologic agents are varied, but commonly include filamentous fungi and Candida. This narrative review describes various sources of potential freshwater fungal exposure and the diseases that may result, including fungal keratitis, acute otitis externa and tinea pedis, as well as rare deep soft tissue or bone infections and pulmonary or central nervous system infections following traumatic freshwater exposure during natural disasters or near-drowning episodes. Fungal etiology should be suspected in appropriate scenarios when bacterial cultures or molecular tests are normal or when the infection worsens or fails to resolve with appropriate antibacterial therapy.

  12. Inhibitors of amino acids biosynthesis as antifungal agents.

    Science.gov (United States)

    Jastrzębowska, Kamila; Gabriel, Iwona

    2015-02-01

    Fungal microorganisms, including the human pathogenic yeast and filamentous fungi, are able to synthesize all proteinogenic amino acids, including nine that are essential for humans. A number of enzymes catalyzing particular steps of human-essential amino acid biosynthesis are fungi specific. Numerous studies have shown that auxotrophic mutants of human pathogenic fungi impaired in biosynthesis of particular amino acids exhibit growth defect or at least reduced virulence under in vivo conditions. Several chemical compounds inhibiting activity of one of these enzymes exhibit good antifungal in vitro activity in minimal growth media, which is not always confirmed under in vivo conditions. This article provides a comprehensive overview of the present knowledge on pathways of amino acids biosynthesis in fungi, with a special emphasis put on enzymes catalyzing particular steps of these pathways as potential targets for antifungal chemotherapy.

  13. Microbial biosynthesis of nontoxic gold nanoparticles

    International Nuclear Information System (INIS)

    Roy, Swarup; Das, Tapan Kumar; Maiti, Guru Prasad; Basu, Utpal

    2016-01-01

    Graphical abstract: The manuscript deals with the fungus mediated optimized biologically synthesized GNPs using Aspergillus foetidus and characterization of biosynthesized GNPs using various physico-chemical methods. The fairly stable synthesized nanoparticles have size in the range of 10–40 nm. Cytotoxicity study of biosynthesized GNPs on Human lung cancer cell line A549 showed no significant toxicity of GNPs. - Highlights: • A novel biosynthesis process of GNPs using Aspergillus foetidus. • Biosynthesized GNPs are in the range of 10–40 nm as observed from TEM. • This process of synthesis is an optimized biosynthesis process of GNPs. • Biosynthesized GNPs are noncytotoxic against A549 cell line. - Abstract: We study the extracellular biosynthesis of gold nanoparticles (GNPs) using the fungal species Aspergillus foetidus. The formation of GNPs were initially monitored by visual observation and then characterized with the help of various characterization techniques. X-ray diffraction (XRD) results revealed distinctive formation of face centered cubic crystalline GNPs. From field emission scanning electron microscopy (FESEM) the morphology of the nanoparticles were found to be roughly spherical and within the size range of 30–50 nm. The spherical and polydispersed GNPs in the range of 10–40 nm were observed by transmission electron microscopy (TEM) analysis. It was established that alkaline pH, 1 mM gold salt concentration and 75 °C temperature were the respective optimum parameter for biosynthesis of GNPs. Cell cytotoxicity of GNP was compared with that of normal gold salt solution on A549 cell. The A549 cell growth in presence of GNPs was found to be comparatively less toxic than the gold ion.

  14. Microbial biosynthesis of nontoxic gold nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Swarup, E-mail: swaruproy@klyuniv.ac.in [Department of Biochemistry and Biophysics, University of Kalyani, Kalyani 741235, West Bengal (India); Das, Tapan Kumar [Department of Biochemistry and Biophysics, University of Kalyani, Kalyani 741235, West Bengal (India); Maiti, Guru Prasad [Department of Molecular Biology and Biotechnology, University of Kalyani, Kalyani 741235, West Bengal (India); Department of Anesthesiology, Texas Tech University Health science Center, 3601 4th Street, Lubbock, TX 79430 (United States); Basu, Utpal [Department of Molecular Biology and Biotechnology, University of Kalyani, Kalyani 741235, West Bengal (India)

    2016-01-15

    Graphical abstract: The manuscript deals with the fungus mediated optimized biologically synthesized GNPs using Aspergillus foetidus and characterization of biosynthesized GNPs using various physico-chemical methods. The fairly stable synthesized nanoparticles have size in the range of 10–40 nm. Cytotoxicity study of biosynthesized GNPs on Human lung cancer cell line A549 showed no significant toxicity of GNPs. - Highlights: • A novel biosynthesis process of GNPs using Aspergillus foetidus. • Biosynthesized GNPs are in the range of 10–40 nm as observed from TEM. • This process of synthesis is an optimized biosynthesis process of GNPs. • Biosynthesized GNPs are noncytotoxic against A549 cell line. - Abstract: We study the extracellular biosynthesis of gold nanoparticles (GNPs) using the fungal species Aspergillus foetidus. The formation of GNPs were initially monitored by visual observation and then characterized with the help of various characterization techniques. X-ray diffraction (XRD) results revealed distinctive formation of face centered cubic crystalline GNPs. From field emission scanning electron microscopy (FESEM) the morphology of the nanoparticles were found to be roughly spherical and within the size range of 30–50 nm. The spherical and polydispersed GNPs in the range of 10–40 nm were observed by transmission electron microscopy (TEM) analysis. It was established that alkaline pH, 1 mM gold salt concentration and 75 °C temperature were the respective optimum parameter for biosynthesis of GNPs. Cell cytotoxicity of GNP was compared with that of normal gold salt solution on A549 cell. The A549 cell growth in presence of GNPs was found to be comparatively less toxic than the gold ion.

  15. Lipopolysaccharide (LPS) stimulation of fungal secondary metabolism

    Science.gov (United States)

    Khalil, Zeinab G.; Kalansuriya, Pabasara; Capon, Robert J.

    2014-01-01

    We report on a preliminary investigation of the use the Gram-negative bacterial cell wall constituent lipopolysaccharide (LPS) as a natural chemical cue to stimulate and alter the expression of fungal secondary metabolism. Integrated high-throughput micro-cultivation and micro-analysis methods determined that 6 of 40 (15%) of fungi tested responded to an optimal exposure to LPS (0.6 ng/mL) by activating, enhancing or accelerating secondary metabolite production. To explore the possible mechanisms behind this effect, we employed light and fluorescent microscopy in conjunction with a nitric oxide (NO)-sensitive fluorescent dye and an NO scavenger to provide evidence that LPS stimulation of fungal secondary metabolism coincided with LPS activation of NO. Several case studies demonstrated that LPS stimulation can be scaled from single microplate well (1.5 mL) to preparative (>400 mL) scale cultures. For example, LPS treatment of Penicillium sp. (ACM-4616) enhanced pseurotin A and activated pseurotin A1 and pseurotin A2 biosynthesis, whereas LPS treatment of Aspergillus sp. (CMB-M81F) substantially accelerated and enhanced the biosynthesis of shornephine A and a series of biosynthetically related ardeemins and activated production of neoasterriquinone. As an indication of broader potential, we provide evidence that cultures of Penicillium sp. (CMB-TF0411), Aspergillus niger (ACM-4993F), Rhizopus oryzae (ACM-165F) and Thanatephorus cucumeris (ACM-194F) were responsive to LPS stimulation, the latter two examples being particular noteworthy as neither are known to produce secondary metabolites. Our results encourage the view that LPS stimulation can be used as a valuable tool to expand the molecular discovery potential of fungal strains that either have been exhaustively studied by or are unresponsive to traditional culture methodology. PMID:25379339

  16. Biosynthesis of tylophora alkaloids

    International Nuclear Information System (INIS)

    Mulchandani, N.B.; Iyer, S.S.; Badheka, L.P.

    1974-01-01

    Using labelled precursors, biosynthesis of the tylophora alkaloids, tylophorine, tylophorinidine and tylophorinide has been investigated in Tylophora asthmatica plants. The radioactive precursors, phenylalanine-2- 14 C, benzoic acid-1- 14 C, benzoic acid-ring 14 C, acetate-2- 14 C, ornithine-5- 14 C, acetate-2- 14 C, ornithine-5- 14 C and cinnamic acid-2- 14 C were administered to the plants individually by wick technique. Tylophorine was isolated in each case and assayed for its radioactivity to find out the incorporation of the label into it. The results indicate that: (1) phenylalanine via cinnamic acid is an important precursor in the biosynthesis of tylophorine (2) orinithine participates in tylophorine biosynthesis via pyrroline and (3) tylophorinidine may be a direct precursor of tylophorine. (M.G.B.)

  17. Biological roles of fungal carotenoids.

    Science.gov (United States)

    Avalos, Javier; Carmen Limón, M

    2015-08-01

    Carotenoids are terpenoid pigments widespread in nature, produced by bacteria, fungi, algae and plants. They are also found in animals, which usually obtain them through the diet. Carotenoids in plants provide striking yellow, orange or red colors to fruits and flowers, and play important metabolic and physiological functions, especially relevant in photosynthesis. Their functions are less clear in non-photosynthetic microorganisms. Different fungi produce diverse carotenoids, but the mutants unable to produce them do not exhibit phenotypic alterations in the laboratory, apart of lack of pigmentation. This review summarizes the current knowledge on the functional basis for carotenoid production in fungi. Different lines of evidence support a protective role of carotenoids against oxidative stress and exposure to visible light or UV irradiation. In addition, the carotenoids are intermediary products in the biosynthesis of physiologically active apocarotenoids or derived compounds. This is the case of retinal, obtained from the symmetrical oxidative cleavage of β-carotene. Retinal is the light-absorbing prosthetic group of the rhodopsins, membrane-bound photoreceptors present also in many fungal species. In Mucorales, β-carotene is an intermediary in the synthesis of trisporoids, apocarotenoid derivatives that include the sexual hormones the trisporic acids, and they are also presumably used in the synthesis of sporopollenin polymers. In conclusion, fungi have adapted their ability to produce carotenoids for different non-essential functions, related with stress tolerance or with the synthesis of physiologically active by-products.

  18. Fungal Genomics Program

    Energy Technology Data Exchange (ETDEWEB)

    Grigoriev, Igor

    2012-03-12

    The JGI Fungal Genomics Program aims to scale up sequencing and analysis of fungal genomes to explore the diversity of fungi important for energy and the environment, and to promote functional studies on a system level. Combining new sequencing technologies and comparative genomics tools, JGI is now leading the world in fungal genome sequencing and analysis. Over 120 sequenced fungal genomes with analytical tools are available via MycoCosm (www.jgi.doe.gov/fungi), a web-portal for fungal biologists. Our model of interacting with user communities, unique among other sequencing centers, helps organize these communities, improves genome annotation and analysis work, and facilitates new larger-scale genomic projects. This resulted in 20 high-profile papers published in 2011 alone and contributing to the Genomics Encyclopedia of Fungi, which targets fungi related to plant health (symbionts, pathogens, and biocontrol agents) and biorefinery processes (cellulose degradation, sugar fermentation, industrial hosts). Our next grand challenges include larger scale exploration of fungal diversity (1000 fungal genomes), developing molecular tools for DOE-relevant model organisms, and analysis of complex systems and metagenomes.

  19. Fungal Skin Infections

    Science.gov (United States)

    ... Abbreviations Weights & Measures ENGLISH View Professional English Deutsch Japanese Espaniol Find information on medical topics, symptoms, drugs, ... touching the infected area. Diagnosis Skin scrapings or cultures Doctors may suspect a fungal infection when they ...

  20. JGI Fungal Genomics Program

    Energy Technology Data Exchange (ETDEWEB)

    Grigoriev, Igor V.

    2011-03-14

    Genomes of energy and environment fungi are in focus of the Fungal Genomic Program at the US Department of Energy Joint Genome Institute (JGI). Its key project, the Genomics Encyclopedia of Fungi, targets fungi related to plant health (symbionts, pathogens, and biocontrol agents) and biorefinery processes (cellulose degradation, sugar fermentation, industrial hosts), and explores fungal diversity by means of genome sequencing and analysis. Over 50 fungal genomes have been sequenced by JGI to date and released through MycoCosm (www.jgi.doe.gov/fungi), a fungal web-portal, which integrates sequence and functional data with genome analysis tools for user community. Sequence analysis supported by functional genomics leads to developing parts list for complex systems ranging from ecosystems of biofuel crops to biorefineries. Recent examples of such 'parts' suggested by comparative genomics and functional analysis in these areas are presented here

  1. Fungal symbiosis unearthed

    Science.gov (United States)

    Daniel Cullen

    2008-01-01

    Associations between plant roots and fungi are a feature of many terrestrial ecosystems. The genome sequence of a prominent fungal partner opens new avenues for studying such mycorrhizal interactions....

  2. Darkness: A Crucial Factor in Fungal Taxol Production

    Directory of Open Access Journals (Sweden)

    Sameh S. M. Soliman

    2018-03-01

    Full Text Available Fungal Taxol acquired lots of attention in the last few decades mainly because of the hope that fungi could be manipulated more easily than yew trees to scale up the production level of this valuable anticancer drug. Several researchers have studied diverse factors to enhance fungal Taxol production. However, up to date fungal Taxol production has never been enhanced to the commercial level. We have hypothesized that optimization of fungal Taxol production may require clear understanding of the fungal habitat in its original host plant. One major feature shared by all fungal endophytes is that they are located in the internal plant tissues where darkness is prominent; hence here the effect of light on fungal Taxol production was tested. Incubation of Taxol-producing endophytic SSM001 fungus in light prior to inoculation in Taxol production culture media showed dramatic loss of Taxol accumulation, significant reduction in Taxol-containing resin bodies and reduction in the expression of genes known to be involved in Taxol biosynthesis. The loss of Taxol production was accompanied by production of dark green pigments. Pigmentation is a fungal protection mechanism which is photoreceptor mediated and induced by light. Opsin, a known photoreceptor involved in light perception and pigment production, was identified in SSM001 by genome sequencing. SSM001 opsin gene expression was induced by white light. The results from this study indicated that the endophytic fungus SSM001 required the dark habitat of its host plant for Taxol production and hence this biosynthetic pathway shows a negative response to light.

  3. The fungal myosin I is essential for Fusarium toxisome formation.

    Directory of Open Access Journals (Sweden)

    Guangfei Tang

    2018-01-01

    Full Text Available Myosin-I molecular motors are proposed to function as linkers between membranes and the actin cytoskeleton in several cellular processes, but their role in the biosynthesis of fungal secondary metabolites remain elusive. Here, we found that the myosin I of Fusarium graminearum (FgMyo1, the causal agent of Fusarium head blight, plays critical roles in mycotoxin biosynthesis. Inhibition of myosin I by the small molecule phenamacril leads to marked reduction in deoxynivalenol (DON biosynthesis. FgMyo1 also governs translation of the DON biosynthetic enzyme Tri1 by interacting with the ribosome-associated protein FgAsc1. Disruption of the ATPase activity of FgMyo1 either by the mutation E420K, down-regulation of FgMyo1 expression or deletion of FgAsc1 results in reduced Tri1 translation. The DON biosynthetic enzymes Tri1 and Tri4 are mainly localized to subcellular structures known as toxisomes in response to mycotoxin induction and the FgMyo1-interacting protein, actin, participates in toxisome formation. The actin polymerization disruptor latrunculin A inhibits toxisome assembly. Consistent with this observation, deletion of the actin-associated proteins FgPrk1 and FgEnd3 also results in reduced toxisome formation. Unexpectedly, the FgMyo1-actin cytoskeleton is not involved in biosynthesis of another secondary metabolite tested. Taken together, this study uncovers a novel function of myosin I in regulating mycotoxin biosynthesis in filamentous fungi.

  4. The fungal myosin I is essential for Fusarium toxisome formation.

    Science.gov (United States)

    Tang, Guangfei; Chen, Yun; Xu, Jin-Rong; Kistler, H Corby; Ma, Zhonghua

    2018-01-01

    Myosin-I molecular motors are proposed to function as linkers between membranes and the actin cytoskeleton in several cellular processes, but their role in the biosynthesis of fungal secondary metabolites remain elusive. Here, we found that the myosin I of Fusarium graminearum (FgMyo1), the causal agent of Fusarium head blight, plays critical roles in mycotoxin biosynthesis. Inhibition of myosin I by the small molecule phenamacril leads to marked reduction in deoxynivalenol (DON) biosynthesis. FgMyo1 also governs translation of the DON biosynthetic enzyme Tri1 by interacting with the ribosome-associated protein FgAsc1. Disruption of the ATPase activity of FgMyo1 either by the mutation E420K, down-regulation of FgMyo1 expression or deletion of FgAsc1 results in reduced Tri1 translation. The DON biosynthetic enzymes Tri1 and Tri4 are mainly localized to subcellular structures known as toxisomes in response to mycotoxin induction and the FgMyo1-interacting protein, actin, participates in toxisome formation. The actin polymerization disruptor latrunculin A inhibits toxisome assembly. Consistent with this observation, deletion of the actin-associated proteins FgPrk1 and FgEnd3 also results in reduced toxisome formation. Unexpectedly, the FgMyo1-actin cytoskeleton is not involved in biosynthesis of another secondary metabolite tested. Taken together, this study uncovers a novel function of myosin I in regulating mycotoxin biosynthesis in filamentous fungi.

  5. Glycopeptide antibiotic biosynthesis.

    Science.gov (United States)

    Yim, Grace; Thaker, Maulik N; Koteva, Kalinka; Wright, Gerard

    2014-01-01

    Glycopeptides such as vancomycin, teicoplanin and telavancin are essential for treating infections caused by Gram-positive bacteria. Unfortunately, the dwindled pipeline of new antibiotics into the market and the emergence of glycopeptide-resistant enterococci and other resistant bacteria are increasingly making effective antibiotic treatment difficult. We have now learned a great deal about how bacteria produce antibiotics. This information can be exploited to develop the next generation of antimicrobials. The biosynthesis of glycopeptides via nonribosomal peptide assembly and unusual amino acid synthesis, crosslinking and tailoring enzymes gives rise to intricate chemical structures that target the bacterial cell wall. This review seeks to describe recent advances in our understanding of both biosynthesis and resistance of these important antibiotics.

  6. Fungal genomics beyond Saccharomyces cerevisiae?

    DEFF Research Database (Denmark)

    Hofmann, Gerald; Mcintyre, Mhairi; Nielsen, Jens

    2003-01-01

    Fungi are used extensively in both fundamental research and industrial applications. Saccharomyces cerevisiae has been the model organism for fungal research for many years, particularly in functional genomics. However, considering the diversity within the fungal kingdom, it is obvious...

  7. Fungal prostatitis: an update.

    Science.gov (United States)

    Mayayo, Emilio; Fernández-Silva, Fabiola

    2014-06-01

    Prostate pathology is a daily occurrence in urological and general medical consultations. Besides hyperplasia and neoplastic pathology, other processes, such as infectious ones, are also documented. Their etiology is diverse and varied. Within the infectious prostatic processes, fungi can also be a specific cause of prostatitis. Fungal prostatitis often appears in patients with impaired immunity and can also be rarely found in healthy patients. It can result from a disseminated infection, but it can also be localized. Fungal prostatitis is a nonspecific and harmless process. Diagnosis is commonly made by fine needle aspiration cytology or by biopsy. A number of fungi can be involved. Although there are not many reported cases, they are becoming more frequent, in particular in patients with some degree of immunodeficiency or those who live in areas where specific fungi are endemic or in visitors of those areas. We present a comprehensive review of the various forms of fungal prostatitis, and we describe the morphological characteristics of the fungi more frequently reported as causes of fungal prostatitis. We also report our own experience, aiming to alert physicians, urologists and pathologists of these particular infections.

  8. Fungal Wound Infection

    Centers for Disease Control (CDC) Podcasts

    2016-01-28

    Dr. David Tribble, acting director of the infectious disease clinical research program at Uniformed Services University of the Health Sciences, discusses fungal wound infections after combat trauma.  Created: 1/28/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 1/28/2016.

  9. The Fungal Kingdom

    NARCIS (Netherlands)

    Heitman, Joseph; Howlett, B.J.; Crous, P.W.; Stukenbrock, E.H.; James, T.Y.; Gow, N.A.R.

    2017-01-01

    Fungi research and knowledge grew rapidly following recent advances in genetics and genomics. This book synthesizes new knowledge with existing information to stimulate new scientific questions and propel fungal scientists on to the next stages of research. This book is a comprehensive guide on

  10. Triterpene biosynthesis in plants.

    Science.gov (United States)

    Thimmappa, Ramesha; Geisler, Katrin; Louveau, Thomas; O'Maille, Paul; Osbourn, Anne

    2014-01-01

    The triterpenes are one of the most numerous and diverse groups of plant natural products. They are complex molecules that are, for the most part, beyond the reach of chemical synthesis. Simple triterpenes are components of surface waxes and specialized membranes and may potentially act as signaling molecules, whereas complex glycosylated triterpenes (saponins) provide protection against pathogens and pests. Simple and conjugated triterpenes have a wide range of applications in the food, health, and industrial biotechnology sectors. Here, we review recent developments in the field of triterpene biosynthesis, give an overview of the genes and enzymes that have been identified to date, and discuss strategies for discovering new triterpene biosynthetic pathways.

  11. The p450 monooxygenase BcABA1 is essential for abscisic acid biosynthesis in Botrytis cinerea

    DEFF Research Database (Denmark)

    Siewers, V.; Smedsgaard, Jørn; Tudzynski, P.

    2004-01-01

    The phytopathogenic ascomycete Botrytis cinerea is known to produce abscisic acid (ABA), which is thought to be involved in host-pathogen interaction. Biochemical analyses had previously shown that, in contrast to higher plants, the fungal ABA biosynthesis probably does not proceed via carotenoids...

  12. Identification of a trichothecene gene cluster and description of the harzianum A biosynthesis pathway in the fungus Trichoderma arundinaceum

    Science.gov (United States)

    Trichothecenes are sesquiterpenes that act like mycotoxins. Their biosynthesis has been mainly studied in the fungal genera Fusarium, where most of the biosynthetic genes (tri) are grouped in a cluster regulated by ambient conditions and regulatory genes. Unexpectedly, few studies are available abou...

  13. Everybody needs sphingolipids, right! Mining for new drug targets in protozoan sphingolipid biosynthesis.

    Science.gov (United States)

    Mina, John G M; Denny, P W

    2018-02-01

    Sphingolipids (SLs) are an integral part of all eukaryotic cellular membranes. In addition, they have indispensable functions as signalling molecules controlling a myriad of cellular events. Disruption of either the de novo synthesis or the degradation pathways has been shown to have detrimental effects. The earlier identification of selective inhibitors of fungal SL biosynthesis promised potent broad-spectrum anti-fungal agents, which later encouraged testing some of those agents against protozoan parasites. In this review we focus on the key enzymes of the SL de novo biosynthetic pathway in protozoan parasites of the Apicomplexa and Kinetoplastidae, outlining the divergence and interconnection between host and pathogen metabolism. The druggability of the SL biosynthesis is considered, alongside recent technology advances that will enable the dissection and analyses of this pathway in the parasitic protozoa. The future impact of these advances for the development of new therapeutics for both globally threatening and neglected infectious diseases is potentially profound.

  14. Role of the Colletotrichum acutatum sesquiterpene synthase CaTPS in the biosynthesis of sesquiterpenoids

    DEFF Research Database (Denmark)

    Amby, Daniel Buchvaldt; Manczak, Tom; Petersen, Mikael Agerlin

    2016-01-01

    biosynthesis is performed by sesquiterpene synthases (TPS). Only a few TPSs have been functionally characterized from filamentous fungi and none from the genus Colletotrichum. Despite being an important fungal pathogen to agriculture, it is poorly understood at the molecular and chemical levels. The terpenoid...... characterization of TPS in Colletotrichum spp. and terpenoid profiles of Coll. acutatum, which could facilitate studies on the role of terpenoids in the ecology of Coll. acutatum....

  15. 46_ _267 - 278__Aminu- Biosynthesis

    African Journals Online (AJOL)

    User

    ISSN 2006 – 6996. BIOSYNTHESIS, CHARACTERIZATION AND ANTIMICROBIAL STUDY OF .... the excitation of surface Plasmon vibration with. AgNPs. ... Thin films of the sample were prepared on a carbon ... The resulting film on the SEM.

  16. Disruption of Sphingolipid Biosynthesis Blocks Phagocytosis of Candida albicans.

    Directory of Open Access Journals (Sweden)

    Fikadu G Tafesse

    2015-10-01

    Full Text Available The ability of phagocytes to clear pathogens is an essential attribute of the innate immune response. The role of signaling lipid molecules such as phosphoinositides is well established, but the role of membrane sphingolipids in phagocytosis is largely unknown. Using a genetic approach and small molecule inhibitors, we show that phagocytosis of Candida albicans requires an intact sphingolipid biosynthetic pathway. Blockade of serine-palmitoyltransferase (SPT and ceramide synthase-enzymes involved in sphingolipid biosynthesis- by myriocin and fumonisin B1, respectively, impaired phagocytosis by phagocytes. We used CRISPR/Cas9-mediated genome editing to generate Sptlc2-deficient DC2.4 dendritic cells, which lack serine palmitoyl transferase activity. Sptlc2-/- DC2.4 cells exhibited a stark defect in phagocytosis, were unable to bind fungal particles and failed to form a normal phagocytic cup to engulf C. albicans. Supplementing the growth media with GM1, the major ganglioside present at the cell surface, restored phagocytic activity of Sptlc2-/- DC2.4 cells. While overall membrane trafficking and endocytic pathways remained functional, Sptlc2-/- DC2.4 cells express reduced levels of the pattern recognition receptors Dectin-1 and TLR2 at the cell surface. Consistent with the in vitro data, compromised sphingolipid biosynthesis in mice sensitizes the animal to C. albicans infection. Sphingolipid biosynthesis is therefore critical for phagocytosis and in vivo clearance of C. albicans.

  17. Trichoderma harzianum: Inhibition of mycotoxin producing fungi and toxin biosynthesis.

    Science.gov (United States)

    Braun, H; Woitsch, L; Hetzer, B; Geisen, R; Zange, B; Schmidt-Heydt, M

    2018-04-19

    A quarter of the world-wide crop is spoiled by filamentous fungi and their mycotoxins and weather extremes associated with the climate change lead to further deterioration of the situation. The ingestion of mycotoxins causes several health issues leading in the worst case to cancer in humans and animals. Common intervention strategies against mycotoxin producing fungi, such as the application of fungicides, may result in undesirable residues and in some cases to a stress induction of mycotoxin biosynthesis. Moreover, development of fungicide resistances has greatly impacted pre- and postharvest fungal diseases. Hence there is the need to develop alternative strategies to reduce fungal infestation and thus mycotoxin contamination in the food chain. Such a strategy for natural competition of important plant-pathogenic and mycotoxin producing fungi could be Trichoderma harzianum, a mycoparasitic fungus. Especially in direct comparison to certain tested fungicides, the inhibition of different tested fungal species by T. harzianum was comparable, more sustainable and in some cases more effective, too. Besides substantially reduced growth rates, a transcriptional based inhibition of mycotoxin biosynthesis in the competed Aspergillus species could be shown. Furthermore it could be clearly observed by high-resolution Scanning Electron Microscopy (SEM) that T. harzianum actively attaches to the competitor species followed by subsequent enzymatic lysis of those mycelial filaments. The analyzed isolate of T. harzianum MRI349 is not known to produce mycotoxins. In this study it could be successfully proven that T. harzianum as a biological competitor is an effective complement to the use of fungicides. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Serine biosynthesis and transport defects.

    Science.gov (United States)

    El-Hattab, Ayman W

    2016-07-01

    l-serine is a non-essential amino acid that is biosynthesized via the enzymes phosphoglycerate dehydrogenase (PGDH), phosphoserine aminotransferase (PSAT), and phosphoserine phosphatase (PSP). Besides its role in protein synthesis, l-serine is a potent neurotrophic factor and a precursor of a number of essential compounds including phosphatidylserine, sphingomyelin, glycine, and d-serine. Serine biosynthesis defects result from impairments of PGDH, PSAT, or PSP leading to systemic serine deficiency. Serine biosynthesis defects present in a broad phenotypic spectrum that includes, at the severe end, Neu-Laxova syndrome, a lethal multiple congenital anomaly disease, intermediately, infantile serine biosynthesis defects with severe neurological manifestations and growth deficiency, and at the mild end, the childhood disease with intellectual disability. A serine transport defect resulting from deficiency of the ASCT1, the main transporter for serine in the central nervous system, has been recently described in children with neurological manifestations that overlap with those observed in serine biosynthesis defects. l-serine therapy may be beneficial in preventing or ameliorating symptoms in serine biosynthesis and transport defects, if started before neurological damage occurs. Herein, we review serine metabolism and transport, the clinical, biochemical, and molecular aspects of serine biosynthesis and transport defects, the mechanisms of these diseases, and the potential role of serine therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Biosynthesis of oleamide.

    Science.gov (United States)

    Mueller, Gregory P; Driscoll, William J

    2009-01-01

    Oleamide (cis-9-octadecenamide) is the prototype long chain primary fatty acid amide lipid messenger. The natural occurrence of oleamide was first reported in human serum in 1989. Subsequently oleamide was shown to accumulate in the cerebrospinal fluid of sleep-deprived cats and to induce sleep when administered to experimental animals. Accordingly, oleamide first became known for its potential role in the mechanisms that mediate the drive to sleep. Oleamide also has profound effects on thermoregulation and acts as an analgesic in several models of experimental pain. Although these important pharmacologic effects are well establish, the biochemical mechanism for the synthesis of oleamide has not yet been defined. This chapter reviews the biosynthetic pathways that have been proposed and highlights two mechanisms which are most supported by experimental evidence: the generation of oleamide from oleoylglycine by the neuropeptide processing enzyme, peptidylglycine alpha-amidating monooxygenase (PAM), and alternatively, the direct amidation of oleic acid via oleoyl coenzyme A by cytochrome c using ammonia as the nitrogen source. The latter mechanism is discussed in the context of apoptosis where oleamide may play a role in regulating gap junction communication. Lastly, several considerations and caveats pertinent to the future study oleamide biosynthesis are discussed.

  20. Glycolipid biosynthesis in cyanobacteria

    International Nuclear Information System (INIS)

    Van Dusen, W.J.; Jaworski, J.G.

    1987-01-01

    The biosynthesis of monogalactosyldiacyl-glycerol (MGDG) was studied in five different cyanobacteria. Previous work has shown Anabaena variabilis to synthesize both MGDG and monoglucosyl-diacylglycerol (MG1cDG) with MG1cDG being the precursor of MGDG. They have examined four other cyanobacteria to determine if a similar relationship exists. The cyanobacteria studied were Anabaena variabilis, Chlorogloeopsis sp., Schizothrix calcicola, Anacystis nidulans, and Anacystis marina. Each were grown in liquid culture and lipids were labeled with 14 C]CO 2 for 20 min., 1.0 hr, 1.0 hr + 10 hr chase. Glycolipids were analyzed by initial separation of MGDG and MG1cDG by TLC followed by further analysis by HPLC. Complete separation of molecular species was obtained isocratically on an ODS column. All of the cyanobacteria labeled 16-C and 18-C fatty acids except for A. marina which labeled only 14-C and 16-C fatty acids. Desaturation of the fatty acids could be observed in the 1.0 hr and chase experiments. All were capable of labeling both MG1cDG and MGDG with the precursor-product relationship being observed. There does not appear to be a direct relationship between the epimerization of the sugar moiety and fatty acid desaturation

  1. Bioregulation of aflatoxin biosynthesis by unirradiated and irradiated conidia of Aspergillus flavus

    International Nuclear Information System (INIS)

    Aziz, N.H.; Abu-Shady, M.R.; El-Fouly, M.Z.; Moussa, L.A.

    1996-01-01

    A sequential technique involving the transfer of mycelia from peptone-based, aflatoxin-non-supporting medium to glucose based, aflatoxin-supporting medium was used to study the effect of γ-irradiation on the regulation of aflatoxin biosynthesis by Aspergillus flavus. Analysis indicated that irradiation at a dose of 1.00 kGy produced enhancement of aflatoxin biosynthesis in peptone-glucose mineral salt cultures with an increase of adenine nucleotide levels and fatty acid patterns of microsomes and mitochondria. The results suggest that aflatoxin synthesis is not regulated by the overall energy status of the fungal cell but that lipoperoxidation by γ-irradiation plays a role in aflatoxin biosynthesis

  2. Fungal biodiversity to biotechnology.

    Science.gov (United States)

    Chambergo, Felipe S; Valencia, Estela Y

    2016-03-01

    Fungal habitats include soil, water, and extreme environments. With around 100,000 fungus species already described, it is estimated that 5.1 million fungus species exist on our planet, making fungi one of the largest and most diverse kingdoms of eukaryotes. Fungi show remarkable metabolic features due to a sophisticated genomic network and are important for the production of biotechnological compounds that greatly impact our society in many ways. In this review, we present the current state of knowledge on fungal biodiversity, with special emphasis on filamentous fungi and the most recent discoveries in the field of identification and production of biotechnological compounds. More than 250 fungus species have been studied to produce these biotechnological compounds. This review focuses on three of the branches generally accepted in biotechnological applications, which have been identified by a color code: red, green, and white for pharmaceutical, agricultural, and industrial biotechnology, respectively. We also discuss future prospects for the use of filamentous fungi in biotechnology application.

  3. Current management of fungal infections.

    NARCIS (Netherlands)

    Meis, J.F.G.M.; Verweij, P.E.

    2001-01-01

    The management of superficial fungal infections differs significantly from the management of systemic fungal infections. Most superficial infections are treated with topical antifungal agents, the choice of agent being determined by the site and extent of the infection and by the causative organism,

  4. The evolution of fungal epiphytes

    NARCIS (Netherlands)

    Hongsanan, S.; Sánchez-Ramírez, S.; Crous, P.W.; Ariyawansa, H.A.; Zhao, R.L.; Hyde, K.D.

    2016-01-01

    Fungal epiphytes are a polyphyletic group found on the surface of plants, particularly on leaves, with a worldwide distribution. They belong in the phylum Ascomycota, which contains the largest known number of fungal genera. There has been little research dating the origins of the common ancestors

  5. Regulation of cell wall biosynthesis.

    Science.gov (United States)

    Zhong, Ruiqin; Ye, Zheng-Hua

    2007-12-01

    Plant cell walls differ in their amount and composition among various cell types and even in different microdomains of the wall of a given cell. Plants must have evolved regulatory mechanisms controlling biosynthesis, targeted secretion, and assembly of wall components to achieve the heterogeneity in cell walls. A number of factors, including hormones, the cytoskeleton, glycosylphosphatidylinositol-anchored proteins, phosphoinositides, and sugar nucleotide supply, have been implicated in the regulation of cell wall biosynthesis or deposition. In the past two years, there have been important discoveries in transcriptional regulation of secondary wall biosynthesis. Several transcription factors in the NAC and MYB families have been shown to be the key switches for activation of secondary wall biosynthesis. These studies suggest a transcriptional network comprised of a hierarchy of transcription factors is involved in regulating secondary wall biosynthesis. Further investigation and integration of the regulatory players participating in the making of cell walls will certainly lead to our understanding of how wall amounts and composition are controlled in a given cell type. This may eventually allow custom design of plant cell walls on the basis of our needs.

  6. Superficial fungal infections.

    Science.gov (United States)

    Schwartz, Robert A

    Superficial fungal infections arise from a pathogen that is restricted to the stratum corneum, with little or no tissue reaction. In this Seminar, three types of infection will be covered: tinea versicolor, piedra, and tinea nigra. Tinea versicolor is common worldwide and is caused by Malassezia spp, which are human saprophytes that sometimes switch from yeast to pathogenic mycelial form. Malassezia furfur, Malassezia globosa, and Malassezia sympodialis are most closely linked to tinea versicolor. White and black piedra are both common in tropical regions of the world; white piedra is also endemic in temperate climates. Black piedra is caused by Piedraia hortae; white piedra is due to pathogenic species of the Trichosporon genus. Tinea nigra is also common in tropical areas and has been confused with melanoma.

  7. Fungal keratitis: A review

    International Nuclear Information System (INIS)

    Jastaneiah, Sabah S.; Al-Rajhi, Ali A.

    2006-01-01

    Keratomycosis is a vision-threatening fungal corneal infection. The dramatic increase in the number of cases over the past three decades is attributable not only to better diagnostic recognition, improved laboratory techniques and greater awareness by the ophthalmic society as a whole, but is also due to a true increase in the incidence of keratitis related to the indiscriminate use of topical broad-spectrum antibiotics, corticosteroids and immunosuppressive drugs, as well as surgical trauma. Corneal trauma has remained the main predisposing factor over the years, though in recent years HIV-positive cases and AIDS are taking lead in certain areas. Aspergillus, Fusarium and Candida species remains the commonest 'organisms' isolated worldwide. Although the approach to this form of keratitis is similar to other types of microbial keratitis, it remains the most difficult in terms of diagnosis and management. Early recognition, prevention, prompt treatment and timely keratoplasty are crucial for a better outcome. (author)

  8. Biosynthesis of silver nanoparticles synthesized by Aspergillus ...

    Indian Academy of Sciences (India)

    Biotechnology Division, Applied Science Department, University of ... Abstract. In the present study, biosynthesis of silver nanoparticles and its antioxidant, antimicrobial and cytotoxic ... example of the biosynthesis using fungi was that the cell-.

  9. Anaerobic fungal populations

    International Nuclear Information System (INIS)

    Brookman, J.L.; Nicholson, M.J.

    2005-01-01

    The development of molecular techniques has greatly broadened our view of microbial diversity and enabled a more complete detection and description of microbial communities. The application of these techniques provides a simple means of following community changes, for example, Ishii et al. described transient and more stable inhabitants in another dynamic microbial system, compost. Our present knowledge of anaerobic gut fungal population diversity within the gastrointestinal tract is based upon isolation, cultivation and observations in vivo. It is likely that there are many species yet to be described, some of which may be non-culturable. We have observed a distinct difference in the ease of cultivation between the different genera, for example, Caecomyes isolates are especially difficult to isolate and maintain in vitro, a feature that is likely to result in the under representation of this genera in culture-based enumerations. The anaerobic gut fungi are the only known obligately anaerobic fungi. For the majority of their life cycles, they are found tightly associated with solid digesta in the rumen and/or hindgut. They produce potent fibrolytic enzymes and grow invasively on and into the plant material they are digesting making them important contributors to fibre digestion. This close association with intestinal digesta has made it difficult to accurately determine the amount of fungal biomass present in the rumen, with Orpin suggesting 8% contribution to the total microbial biomass, whereas Rezaeian et al. more recently gave a value of approximately 20%. It is clear that the rumen microbial complement is affected by dietary changes, and that the fungi are more important in digestion in the rumens of animals fed with high-fibre diets. It seems likely that the gut fungi play an important role within the rumen as primary colonizers of plant fibre, and so we are particularly interested in being able to measure the appearance and diversity of fungi on the plant

  10. Hospitalized Patients and Fungal Infections

    Science.gov (United States)

    ... are mild skin rashes, but others can be deadly, like fungal pneumonia. Because of this, it’s important ... the environment. Fungi live outdoors in soil, on plants, trees, and other vegetation. They are also on ...

  11. Cancer Patients and Fungal Infections

    Science.gov (United States)

    ... are mild skin rashes, but others can be deadly, like fungal pneumonia. Because of this, it’s important ... the environment. Fungi live outdoors in soil, on plants, trees, and other vegetation. They are also on ...

  12. Structural Analysis of Fungal Cerebrosides

    Directory of Open Access Journals (Sweden)

    Eliana eBarreto-Bergter

    2011-12-01

    Full Text Available Of the ceramide monohexosides (CMHs, gluco- and galactosylceramides are the main neutral glycosphingolipids expressed in fungal cells. Their structural determination is greatly dependent on the use of mass spectrometric techniques, including fast atom bombardment-mass spectrometry (FAB-MS, electrospray ionization (ESI-MS, and energy collision-induced dissociation mass spectrometry (ESI-MS/CID-MS. Nuclear magnetic resonance (NMR has also been used successfully. Such a combination of techniques, combined with classical analytical separation, such as HPTLC and column chromatography, has led to the structural elucidation of a great number of fungal CMHs. The structure of fungal CMH is conserved among fungal species and consists of a glucose or galactose residue attached to a ceramide moiety containing 9-methyl-4,8-sphingadienine with an amidic linkage to hydroxylated fatty acids, most commonly having 16 or 18 carbon atoms and unsaturation between C-3 and C-4. Along with their unique structural characteristics, fungal CMHs have a peculiar subcellular distribution and striking biological properties. Fungal cerebrosides were also characterized as antigenic molecules directly or indirectly involved in cell growth or differentiation in Schizophyllum commune, Cryptococcus neoformans, Pseudallescheria boydii, Candida albicans, Aspergillus nidulans, A.fumigatus and Colletotrichum gloeosporioides. Besides classical techniques for cerebroside (CMH analysis, we now describe new approaches, combining conventional TLC and mass spectrometry, as well as emerging technologies for subcellular localization and distribution of glycosphingolipids by SIMS and imaging MALDI TOF .

  13. Serious fungal infections in Ecuador.

    Science.gov (United States)

    Zurita, J; Denning, D W; Paz-Y-Miño, A; Solís, M B; Arias, L M

    2017-06-01

    There is a dearth of data from Ecuador on the burden of life-threatening fungal disease entities; therefore, we estimated the burden of serious fungal infections in Ecuador based on the populations at risk and available epidemiological databases and publications. A full literature search was done to identify all epidemiology papers reporting fungal infection rates. WHO, ONU-AIDS, Index Mundi, Global Asthma Report, Globocan, and national data [Instituto Nacional de Estadística y Censos (INEC), Ministerio de Salud Pública (MSP), Sociedad de Lucha Contra el Cáncer (SOLCA), Instituto Nacional de Donación y Trasplante de Órganos, Tejidos y Células (INDOT)] were reviewed. When no data existed, risk populations were used to estimate frequencies of fungal infections, using previously described methodology by LIFE. Ecuador has a variety of climates from the cold of the Andes through temperate to humid hot weather at the coast and in the Amazon basin. Ecuador has a population of 15,223,680 people and an average life expectancy of 76 years. The median estimate of the human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) population at risk for fungal disease (Ecuador is affected by serious fungal infection.

  14. Evaluation of pulmonary fungal diseases in patients with fungal rhino-sinusitis

    Directory of Open Access Journals (Sweden)

    M.Sh. Badawy

    2013-07-01

    Conclusion: Universal screening for pulmonary fungal infection especially in patients with fungal rhino sinusitis is highly recommended to treat it early, decrease morbidity and mortality of the diseases.

  15. The Dent Stage of Maize Kernels Is the Most Conducive for Fumonisin Biosynthesis under Field Conditions ▿

    OpenAIRE

    Picot, Adeline; Barreau, Christian; Pinson-Gadais, Laëtitia; Piraux, François; Caron, Daniel; Lannou, Christian; Richard-Forget, Florence

    2011-01-01

    The fungal pathogen Fusarium verticillioides infects maize ears and produces fumonisins, known for their adverse effects on human and animal health. Basic questions remain unanswered regarding the kernel stage(s) associated with fumonisin biosynthesis and the kernel components involved in fumonisin regulation during F. verticillioides-maize interaction under field conditions. In this 2-year field study, the time course of F. verticillioides growth and fumonisin accumulation in developing maiz...

  16. Microbiological diagnostics of fungal infections

    Directory of Open Access Journals (Sweden)

    Corrado Girmenia

    2013-07-01

    Full Text Available Laboratory tests for the detection of fungal infections are easy to perform. The main obstacle to a correct diagnosis is the correlation between the laboratory findings and the clinical diagnosis. Among pediatric patients, the most common fungal pathogen is Candida. The detection of fungal colonization may be performed through the use of chromogenic culture media, which allows also the identification of Candida subspecies, from which pathogenicity depends. In neonatology, thistest often drives the decision to begin a empiric therapy; in this regard, a close cooperation between microbiologists and clinicians is highly recommended. Blood culture, if positive, is a strong confirmation of fungal infection; however, its low sensitivity results in a high percentage of false negatives, thus decreasing its reliability. Molecular diagnostics is still under evaluation, whereas the detection of some fungal antigens, such as β-D-glucan, galactomannan, mannoprotein, and cryptococcal antigen in the serum is used for adults, but still under evaluations for pediatric patients.http://dx.doi.org/10.7175/rhc.v4i1S.862

  17. The enzymology of polyether biosynthesis.

    Science.gov (United States)

    Liu, Tiangang; Cane, David E; Deng, Zixin

    2009-01-01

    Polyether ionophore antibiotics are a special class of polyketides widely used in veterinary medicine, and as food additives in animal husbandry. In this article, we review current knowledge about the mechanism of polyether biosynthesis, and the genetic and biochemical strategies used for its study. Several clear differences distinguish it from traditional type I modular polyketide biosynthesis: polyether backbones are assembled by modular polyketide synthases but are modified by two key enzymes, epoxidase and epoxide hydrolase, to generate the product. All double bonds involved in the oxidative cyclization in the polyketide backbone are of E geometry. Chain release in the polyether biosynthetic pathway requires a special type II thioesterase which specifically hydrolyzes the polyether thioester. All these discoveries should be very helpful for a deep understanding of the biosynthetic mechanism of this class of important natural compounds, and for the targeted engineering of polyether derivatives.

  18. DGAT enzymes and triacylglycerol biosynthesis

    OpenAIRE

    Yen, Chi-Liang Eric; Stone, Scot J.; Koliwad, Suneil; Harris, Charles; Farese, Robert V.

    2008-01-01

    Triacylglycerols (triglycerides) (TGs) are the major storage molecules of metabolic energy and FAs in most living organisms. Excessive accumulation of TGs, however, is associated with human diseases, such as obesity, diabetes mellitus, and steatohepatitis. The final and the only committed step in the biosynthesis of TGs is catalyzed by acyl-CoA:diacylglycerol acyltransferase (DGAT) enzymes. The genes encoding two DGAT enzymes, DGAT1 and DGAT2, were identified in the past decade, ...

  19. The Fungal Defensin Family Enlarged

    Directory of Open Access Journals (Sweden)

    Jiajia Wu

    2014-08-01

    Full Text Available Fungi are an emerging source of peptide antibiotics. With the availability of a large number of model fungal genome sequences, we can expect that more and more fungal defensin-like peptides (fDLPs will be discovered by sequence similarity search. Here, we report a total of 69 new fDLPs encoded by 63 genes, in which a group of fDLPs derived from dermatophytes are defined as a new family (fDEF8 according to sequence and phylogenetic analyses. In the oleaginous fungus Mortierella alpine, fDLPs have undergone extensive gene expansion. Our work further enlarges the fungal defensin family and will help characterize new peptide antibiotics with therapeutic potential.

  20. Fungal contamination in hospital environments.

    Science.gov (United States)

    Perdelli, F; Cristina, M L; Sartini, M; Spagnolo, A M; Dallera, M; Ottria, G; Lombardi, R; Grimaldi, M; Orlando, P

    2006-01-01

    To assess the degree of fungal contamination in hospital environments and to evaluate the ability of air conditioning systems to reduce such contamination. We monitored airborne microbial concentrations in various environments in 10 hospitals equipped with air conditioning. Sampling was performed with a portable Surface Air System impactor with replicate organism detection and counting plates containing a fungus-selective medium. The total fungal concentration was determined 72-120 hours after sampling. The genera most involved in infection were identified by macroscopic and microscopic observation. The mean concentration of airborne fungi in the set of environments examined was 19 +/- 19 colony-forming units (cfu) per cubic meter. Analysis of the fungal concentration in the different types of environments revealed different levels of contamination: the lowest mean values (12 +/- 14 cfu/m(3)) were recorded in operating theaters, and the highest (45 +/- 37 cfu/m(3)) were recorded in kitchens. Analyses revealed statistically significant differences between median values for the various environments. The fungal genus most commonly encountered was Penicillium, which, in kitchens, displayed the highest mean airborne concentration (8 +/- 2.4 cfu/m(3)). The percentage (35%) of Aspergillus documented in the wards was higher than that in any of the other environments monitored. The fungal concentrations recorded in the present study are comparable to those recorded in other studies conducted in hospital environments and are considerably lower than those seen in other indoor environments that are not air conditioned. These findings demonstrate the effectiveness of air-handling systems in reducing fungal contamination.

  1. Stem Cell Transplant Patients and Fungal Infections

    Science.gov (United States)

    ... Foodborne, Waterborne, and Environmental Diseases Mycotic Diseases Branch Stem Cell Transplant Patients and Fungal Infections Recommend on Facebook ... Mold . Top of Page Preventing fungal infections in stem cell transplant patients Fungi are difficult to avoid because ...

  2. The dynamic organization of fungal acetyl-CoA carboxylase

    Science.gov (United States)

    Hunkeler, Moritz; Stuttfeld, Edward; Hagmann, Anna; Imseng, Stefan; Maier, Timm

    2016-04-01

    Acetyl-CoA carboxylases (ACCs) catalyse the committed step in fatty-acid biosynthesis: the ATP-dependent carboxylation of acetyl-CoA to malonyl-CoA. They are important regulatory hubs for metabolic control and relevant drug targets for the treatment of the metabolic syndrome and cancer. Eukaryotic ACCs are single-chain multienzymes characterized by a large, non-catalytic central domain (CD), whose role in ACC regulation remains poorly characterized. Here we report the crystal structure of the yeast ACC CD, revealing a unique four-domain organization. A regulatory loop, which is phosphorylated at the key functional phosphorylation site of fungal ACC, wedges into a crevice between two domains of CD. Combining the yeast CD structure with intermediate and low-resolution data of larger fragments up to intact ACCs provides a comprehensive characterization of the dynamic fungal ACC architecture. In contrast to related carboxylases, large-scale conformational changes are required for substrate turnover, and are mediated by the CD under phosphorylation control.

  3. Fungal Endophytes: Beyond Herbivore Management

    Directory of Open Access Journals (Sweden)

    Bamisope S. Bamisile

    2018-03-01

    Full Text Available The incorporation of entomopathogenic fungi as biocontrol agents into Integrated Pest Management (IPM programs without doubt, has been highly effective. The ability of these fungal pathogens such as Beauveria bassiana and Metarhizium anisopliae to exist as endophytes in plants and protect their colonized host plants against the primary herbivore pests has widely been reported. Aside this sole role of pest management that has been traditionally ascribed to fungal endophytes, recent findings provided evidence of other possible functions as plant yield promoter, soil nutrient distributor, abiotic stress and drought tolerance enhancer in plants. However, reports on these additional important effects of fungal endophytes on the colonized plants remain scanty. In this review, we discussed the various beneficial effects of endophytic fungi on the host plants and their primary herbivore pests; as well as some negative effects that are relatively unknown. We also highlighted the prospects of our findings in further increasing the acceptance of fungal endophytes as an integral part of pest management programs for optimized crop production.

  4. DEMONSTRATION BULLETIN: FUNGAL TREATMENT BULLETIN

    Science.gov (United States)

    Fungal treatment technology uses white rot fungi (lignin degrading fungi) to treat organic contaminated soils in situ. Organic materials inoculated with the fungi are mechanically mixed into the contaminated soil. Using enzymes normally produced for wood degradation as well as ot...

  5. [Fungal infections of the gastrointestinal tract].

    Science.gov (United States)

    Maragkoudakis, Emmanouil; Realdi, Giuseppe; Dore, Maria Pina

    2005-06-01

    In immunocompetent subjects fungal infections of the gastrointestinal tract are uncommon. Candida esophagitis remains the single most common fungal infection in immunocompromised hosts or in H. pylori- infected patients who receive antibiotic therapy. Enteric fungal infections are uncommon even in HIV-infected patients. Antifungal agents such as amphotericin B, ketoconazole, fluconazole, and the various formulations of itraconazole are effective for most cases.

  6. Daphnia can protect diatoms from fungal parasitism

    NARCIS (Netherlands)

    Kagami, M.; Van Donk, E.; De Bruin, A.; Rijkeboer, M.; Ibelings, B.W.

    2004-01-01

    Many phytoplankton species are susceptible to chytrid fungal parasitism. Much attention has been paid to abiotic factors that determine whether fungal infections become epidemic. It is still unknown, however, how biotic factors, such as interactions with zooplankton, affect the fungal infection

  7. Evolution and functional insights of different ancestral orthologous clades of chitin synthase genes in the fungal tree of life

    Directory of Open Access Journals (Sweden)

    Mu eLi

    2016-02-01

    Full Text Available Chitin synthases (CHSs are key enzymes in the biosynthesis of chitin, an important structural component of fungal cell walls that can trigger innate immune responses in host plants and animals. Members of CHS gene family perform various functions in fungal cellular processes. Previous studies focused primarily on classifying diverse CHSs into different classes, regardless of their functional diversification, or on characterizing their functions in individual fungal species. A complete and systematic comparative analysis of CHS genes based on their orthologous relationships will be valuable for elucidating the evolution and functions of different CHS genes in fungi. Here, we identified and compared members of the CHS gene family across the fungal tree of life, including 18 divergent fungal lineages. Phylogenetic analysis revealed that the fungal CHS gene family is comprised of at least 10 ancestral orthologous clades, which have undergone multiple independent duplications and losses in different fungal lineages during evolution. Interestingly, one of these CHS clades (class III was expanded in plant or animal pathogenic fungi belonging to different fungal lineages. Two clades (classes VIb and VIc identified for the first time in this study occurred mainly in plant pathogenic fungi from Sordariomycetes and Dothideomycetes. Moreover, members of classes III and VIb were specifically up-regulated during plant infection, suggesting important roles in pathogenesis. In addition, CHS-associated networks conserved among plant pathogenic fungi are involved in various biological processes, including sexual reproduction and plant infection. We also identified specificity-determining sites, many of which are located at or adjacent to important structural and functional sites that are potentially responsible for functional divergence of different CHS classes. Overall, our results provide new insights into the evolution and function of members of CHS gene

  8. Subseafloor basalts as fungal habitats

    Directory of Open Access Journals (Sweden)

    M. Ivarsson

    2012-09-01

    Full Text Available The oceanic crust is believed to host the largest potential habitat for microbial life on Earth, yet, still we lack substantial information about the abundance, diversity, and consequence of its biosphere. The last two decades have involved major research accomplishments within this field and a change in view of the ocean crust and its potential to harbour life. Here fossilised fungal colonies in subseafloor basalts are reported from three different seamounts in the Pacific Ocean. The fungal colonies consist of various characteristic structures interpreted as fungal hyphae, fruit bodies and spores. The fungal hyphae are well preserved with morphological characteristics such as hyphal walls, septa, thallic conidiogenesis, and hyphal tips with hyphal vesicles within. The fruit bodies consist of large (∼50–200 µm in diameter body-like structures with a defined outer membrane and an interior filled with calcite. The fruit bodies have at some stage been emptied of their contents of spores and filled by carbonate-forming fluids. A few fruit bodies not filled by calcite and with spores still within support this interpretation. Spore-like structures (ranging from a few µm to ∼20 µm in diameter are also observed outside of the fruit bodies and in some cases concentrated to openings in the membrane of the fruit bodies. The hyphae, fruit bodies and spores are all closely associated with a crust lining the vein walls that probably represent a mineralized biofilm. The results support a fungal presence in deep subseafloor basalts and indicate that such habitats were vital between ∼81 and 48 Ma.

  9. DIAGNOSIS & MANAGEMENT OF ALLERGIC FUNGAL SINUSITIS

    Directory of Open Access Journals (Sweden)

    Syam Manohar Gadhamsetty

    2016-08-01

    Full Text Available BACKGROUND Chronic sinusitis is one of the common diagnosis in ENT practice. Allergic fungal sinusitis is a clinical entity with characteristic clinical, radiographic and histopathological findings. Allergic fungal sinusitis and eosinophilic mucin rhinosinusitis can easily be misdiagnosed. AIM OF STUDY A prospective clinical study of allergic Fungal Rhinosinusitis to use diagnostic criteria to confirm the disease with Radiological, Pathological & Microbiological investigations and their management. MATERIALS & METHODS A prospective study of allergic Fungal Rhinosinusitis in 2 years from November 2011 to October 2013. Among the patients who attended the ENT OPD during this period, 21 patients with symptoms and signs suggestive of Allergic Fungal Rhinosinusitis are selected.

  10. Oleic acid biosynthesis in cyanobacteria

    International Nuclear Information System (INIS)

    VanDusen, W.J.; Jaworski, J.G.

    1986-01-01

    The biosynthesis of fatty acids in cyanobacteria is very similar to the well characterized system found in green plants. However, the initial desaturation of stearic acid in cyanobacteria appears to represent a significant departure from plant systems in which stearoyl-ACP is the exclusive substrate for desaturation. In Anabaena variabilis, the substrate appears to be monoglucosyldiacylglycerol, a lipid not found in plants. The authors examined five different cyanobacteria to determine if the pathway in A. variabilis was generally present in other cyanobacteria. The cyanobacteria studied were A. variabilis, Chlorogloeopsis sp., Schizothrix calcicola, Anacystis marina, and Anacystis nidulans. Each were grown in liquid culture, harvested, and examined for stearoyl-ACP desaturase activity or incubated with 14 CO 2 . None of the cyanobacteria contained any stearoyl-ACP desaturase activity in whole homogenates or 105,000g supernatants. All were capable of incorporating 14 CO 2 into monoglucosyldiacylglycerol and results from incubations of 20 min, 1 hr, 1 hr + 10 hr chase were consistent with monoglucosyldiacylglycerol serving as precursor for monogalctosyldiacylglycerol. Thus, initial evidence is consistent with oleic acid biosynthesis occurring by desaturation of stearoyl-monoglucosyldiacylglycerol in all cyanobacteria

  11. Volatiles from the fungal microbiome of the marine sponge Callyspongia cf. flammea.

    Science.gov (United States)

    Barra, Lena; Barac, Paul; König, Gabriele M; Crüsemann, Max; Dickschat, Jeroen S

    2017-09-13

    The volatiles emitted by five fungal strains previously isolated from the marine sponge Callyspongia cf. flammea were captured with a closed-loop stripping apparatus (CLSA) and analyzed by GC-MS. Besides several widespread compounds, a series of metabolites with interesting bioactivities were found, including the quorum sensing inhibitor protoanemonin, the fungal phytotoxin 3,4-dimethylpentan-4-olide, and the insect attractant 1,2,4-trimethoxybenzene. In addition, the aromatic polyketides isotorquatone and chartabomone that are both known from Eucalyptus and a new O-desmethyl derivative were identified. The biosynthesis of isotorquatone was studied by feeding experiments with isotopically labeled precursors and its absolute configuration was determined by enantioselective synthesis of a reference compound. Bioactivity testings showed algicidal activity for some of the identified compounds, suggesting a potential ecological function in sponge defence.

  12. The importance of mass spectrometric dereplication in fungal secondary metabolite analysis

    DEFF Research Database (Denmark)

    Nielsen, Kristian Fog; Larsen, Thomas Ostenfeld

    2015-01-01

    Having entered the Genomic Era, it is now evident that the biosynthetic potential of filamentous fungi is much larger than was thought even a decade ago. Fungi harbor many cryptic gene clusters encoding for the biosynthesis of polyketides, non-ribosomal peptides, and terpenoids - which can all...... the importance of each stage of the process from sample preparation to chromatographic separation and finally toward both manual and more targeted methods for automated dereplication of fungal natural products using state-of-the art MS instrumentation....

  13. Subseafloor basalts as fungal habitats

    Science.gov (United States)

    Ivarsson, M.; Bengtson, S.

    2013-12-01

    The oceanic crust makes up the largest potential habitat for life on Earth, yet next to nothing is known about the abundance, diversity and ecology of its biosphere. Our understanding of the deep biosphere of subseafloor crust is, with a few exceptions, based on a fossil record. Surprisingly, a majority of the fossilized microorganisms have been interpreted or recently re-interpreted as remnants of fungi rather than prokaryotes. Even though this might be due to a bias in fossilization the presence of fungi in these settings can not be neglected. We have examined fossilized microorganisms in drilled basalt samples collected at the Emperor Seamounts in the Pacific Ocean. Synchrotron-radiation X-ray tomography microscopy (SRXTM) studies has revealed a complex morphology and internal structure that corresponds to characteristic fungal morphology. Chitin was detected in the fossilized hyphae, which is another strong argument in favour of a fungal interpretation. Chitin is absent in prokaryotes but a substantial constituent in fungal cell walls. The fungal colonies consist of both hyphae and yeast-like growth states as well as resting structures and possible fruit bodies, thus, the fungi exist in vital colonies in subseafloor basalts. The fungi have also been involved in extensive weathering of secondary mineralisations. In terrestrial environments fungi are known as an important geobiological agent that promotes mineral weathering and decomposition of organic matter, and they occur in vital symbiosis with other microorganisms. It is probable to assume that fungi would play a similar role in subseafloor basalts and have great impact on the ecology and on biogeochemical cycles in such environments.

  14. Systemic fungal infections in neonates

    Directory of Open Access Journals (Sweden)

    Rao S

    2005-01-01

    Full Text Available Advances in neonatal management have led to considerable improvement in newborn survival. However, early (72hours onset systemic infections, both bacterial and fungal, remain a devastating complication and an important cause of morbidity and mortality in these babies. Most neonatal fungal infections are due to Candida species, particularly Candida albicans. The sources of candidiasis in NICU are often endogenous following colonization of the babies with fungi. About 10% of these babies get colonized in first week of life and up to 64% babies get colonized by 4 weeks of hospital stay. Disseminated candidiasis presents like bacterial sepsis and can involve multiple organs such as the kidneys, brain, eye, liver, spleen, bone, joints, meninges and heart. Confirming the diagnosis by laboratory tests is difficult and a high index of suspicion is required. The diagnosis of fungemia can be made definitely only by recovering the organism from blood or other sterile bodily fluid. Amphotericin B continues to be the mainstay of therapy for systemic fungal infections but its use is limited by the risks of nephrotoxicity and hypokalemia. Newer formulations of amphotericin B, namely the liposomal and the lipid complex forms, have recently become available and have been reported to have lesser toxicity. More recently Indian liposomal Amphotericin B derived from neutral lipids (L-Amp -LRC-1 has shown good response with less toxicity. A clinical trial with this preparation has shown to be safe and efficacious in neonatal fungal infections. Compared to other liposomal preparations, L-Amp-LRC-1 is effective at lower dose and is less expensive drug for the treatment of neonatal candidiasis.

  15. Systems biology of fungal infection

    Directory of Open Access Journals (Sweden)

    Fabian eHorn

    2012-04-01

    Full Text Available Elucidation of pathogenicity mechanisms of the most important human pathogenic fungi, Aspergillus fumigatus and Candida albicans, has gained great interest in the light of the steadily increasing number of cases of invasive fungal infections.A key feature of these infections is the interaction of the different fungal morphotypes with epithelial and immune effector cells in the human host. Because of the high level of complexity, it is necessary to describe and understand invasive fungal infection by taking a systems biological approach, i.e., by a comprehensive quantitative analysis of the non-linear and selective interactions of a large number of functionally diverse, and frequently multifunctional, sets of elements, e.g., genes, proteins, metabolites, which produce coherent and emergent behaviours in time and space. The recent advances in systems biology will now make it possible to uncover the structure and dynamics of molecular and cellular cause-effect relationships within these pathogenic interactions.We review current efforts to integrate omics and image-based data of host-pathogen interactions into network and spatio-temporal models. The modelling will help to elucidate pathogenicity mechanisms and to identify diagnostic biomarkers and potential drug targets for therapy and could thus pave the way for novel intervention strategies based on novel antifungal drugs and cell therapy.

  16. Fungal genome resources at NCBI

    Science.gov (United States)

    Robbertse, B.; Tatusova, T.

    2011-01-01

    The National Center for Biotechnology Information (NCBI) is well known for the nucleotide sequence archive, GenBank and sequence analysis tool BLAST. However, NCBI integrates many types of biomolecular data from variety of sources and makes it available to the scientific community as interactive web resources as well as organized releases of bulk data. These tools are available to explore and compare fungal genomes. Searching all databases with Fungi [organism] at http://www.ncbi.nlm.nih.gov/ is the quickest way to find resources of interest with fungal entries. Some tools though are resources specific and can be indirectly accessed from a particular database in the Entrez system. These include graphical viewers and comparative analysis tools such as TaxPlot, TaxMap and UniGene DDD (found via UniGene Homepage). Gene and BioProject pages also serve as portals to external data such as community annotation websites, BioGrid and UniProt. There are many different ways of accessing genomic data at NCBI. Depending on the focus and goal of research projects or the level of interest, a user would select a particular route for accessing genomic databases and resources. This review article describes methods of accessing fungal genome data and provides examples that illustrate the use of analysis tools. PMID:22737589

  17. Integrated proteomics and metabolomics suggests symbiotic metabolism and multimodal regulation in a fungal-endobacterial system.

    Science.gov (United States)

    Li, Zhou; Yao, Qiuming; Dearth, Stephen P; Entler, Matthew R; Castro Gonzalez, Hector F; Uehling, Jessie K; Vilgalys, Rytas J; Hurst, Gregory B; Campagna, Shawn R; Labbé, Jessy L; Pan, Chongle

    2017-03-01

    Many plant-associated fungi host endosymbiotic endobacteria with reduced genomes. While endobacteria play important roles in these tri-partite plant-fungal-endobacterial systems, the active physiology of fungal endobacteria has not been characterized extensively by systems biology approaches. Here, we use integrated proteomics and metabolomics to characterize the relationship between the endobacterium Mycoavidus sp. and the root-associated fungus Mortierella elongata. In nitrogen-poor media, M. elongata had decreased growth but hosted a large and growing endobacterial population. The active endobacterium likely extracted malate from the fungal host as the primary carbon substrate for energy production and biosynthesis of phospho-sugars, nucleobases, peptidoglycan and some amino acids. The endobacterium obtained nitrogen by importing a variety of nitrogen-containing compounds. Further, nitrogen limitation significantly perturbed the carbon and nitrogen flows in the fungal metabolic network. M. elongata regulated many pathways by concordant changes on enzyme abundances, post-translational modifications, reactant concentrations and allosteric effectors. Such multimodal regulations may be a general mechanism for metabolic modulation. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  18. Swainsonine Biosynthesis Genes in Diverse Symbiotic and Pathogenic Fungi

    Directory of Open Access Journals (Sweden)

    Daniel Cook

    2017-06-01

    Full Text Available Swainsonine—a cytotoxic fungal alkaloid and a potential cancer therapy drug—is produced by the insect pathogen and plant symbiont Metarhizium robertsii, the clover pathogen Slafractonia leguminicola, locoweed symbionts belonging to Alternaria sect. Undifilum, and a recently discovered morning glory symbiont belonging to order Chaetothyriales. Genome sequence analyses revealed that these fungi share orthologous gene clusters, designated “SWN,” which included a multifunctional swnK gene comprising predicted adenylylation and acyltransferase domains with their associated thiolation domains, a β-ketoacyl synthase domain, and two reductase domains. The role of swnK was demonstrated by inactivating it in M. robertsii through homologous gene replacement to give a ∆swnK mutant that produced no detectable swainsonine, then complementing the mutant with the wild-type gene to restore swainsonine biosynthesis. Other SWN cluster genes were predicted to encode two putative hydroxylases and two reductases, as expected to complete biosynthesis of swainsonine from the predicted SwnK product. SWN gene clusters were identified in six out of seven sequenced genomes of Metarhzium species, and in all 15 sequenced genomes of Arthrodermataceae, a family of fungi that cause athlete’s foot and ringworm diseases in humans and other mammals. Representative isolates of all of these species were cultured, and all Metarhizium spp. with SWN clusters, as well as all but one of the Arthrodermataceae, produced swainsonine. These results suggest a new biosynthetic hypothesis for this alkaloid, extending the known taxonomic breadth of swainsonine producers to at least four orders of Ascomycota, and suggest that swainsonine has roles in mutualistic symbioses and diseases of plants and animals.

  19. DGAT enzymes and triacylglycerol biosynthesis

    Science.gov (United States)

    Yen, Chi-Liang Eric; Stone, Scot J.; Koliwad, Suneil; Harris, Charles; Farese, Robert V.

    2008-01-01

    Triacylglycerols (triglycerides) (TGs) are the major storage molecules of metabolic energy and FAs in most living organisms. Excessive accumulation of TGs, however, is associated with human diseases, such as obesity, diabetes mellitus, and steatohepatitis. The final and the only committed step in the biosynthesis of TGs is catalyzed by acyl-CoA:diacylglycerol acyltransferase (DGAT) enzymes. The genes encoding two DGAT enzymes, DGAT1 and DGAT2, were identified in the past decade, and the use of molecular tools, including mice deficient in either enzyme, has shed light on their functions. Although DGAT enzymes are involved in TG synthesis, they have distinct protein sequences and differ in their biochemical, cellular, and physiological functions. Both enzymes may be useful as therapeutic targets for diseases. Here we review the current knowledge of DGAT enzymes, focusing on new advances since the cloning of their genes, including possible roles in human health and diseases. PMID:18757836

  20. Biosynthesis, characterization and antibacterial activity of silver nanoparticles using an endophytic fungal supernatant of Raphanus sativus

    Directory of Open Access Journals (Sweden)

    Tej Singh

    2017-06-01

    Full Text Available In this study, biological synthesis of silver nanoparticles (AgNPs from supernatant of endophytic fungus Alternaria sp. isolated from the healthy leaves of Raphanus sativus is studied. The synthesized AgNPs are characterized using UV-vis spectroscopy and Fourier transform-infrared spectroscopy (FTIR. The structural analysis is done by powder X-ray diffraction (XRD method. The stability of AgNPs is studied by dynamic light scattering (DLS method. The size and shape of AgNPs are observed by transmission electron microscopy (TEM and atomic force microscopy (AFM and found to be spherical with an average particles size of 4–30 nm. Further, these AgNPs have been found to be highly toxic against human pathogenic bacteria, suggesting the possibility of using AgNPs as efficient antibacterial agents.

  1. ChIP-seq and in vivo transcriptome analyses of the Aspergillus fumigatus SREBP SrbA reveals a new regulator of the fungal hypoxia response and virulence.

    Directory of Open Access Journals (Sweden)

    Dawoon Chung

    2014-11-01

    Full Text Available The Aspergillus fumigatus sterol regulatory element binding protein (SREBP SrbA belongs to the basic Helix-Loop-Helix (bHLH family of transcription factors and is crucial for antifungal drug resistance and virulence. The latter phenotype is especially striking, as loss of SrbA results in complete loss of virulence in murine models of invasive pulmonary aspergillosis (IPA. How fungal SREBPs mediate fungal virulence is unknown, though it has been suggested that lack of growth in hypoxic conditions accounts for the attenuated virulence. To further understand the role of SrbA in fungal infection site pathobiology, chromatin immunoprecipitation followed by massively parallel DNA sequencing (ChIP-seq was used to identify genes under direct SrbA transcriptional regulation in hypoxia. These results confirmed the direct regulation of ergosterol biosynthesis and iron uptake by SrbA in hypoxia and revealed new roles for SrbA in nitrate assimilation and heme biosynthesis. Moreover, functional characterization of an SrbA target gene with sequence similarity to SrbA identified a new transcriptional regulator of the fungal hypoxia response and virulence, SrbB. SrbB co-regulates genes involved in heme biosynthesis and demethylation of C4-sterols with SrbA in hypoxic conditions. However, SrbB also has regulatory functions independent of SrbA including regulation of carbohydrate metabolism. Loss of SrbB markedly attenuates A. fumigatus virulence, and loss of both SREBPs further reduces in vivo fungal growth. These data suggest that both A. fumigatus SREBPs are critical for hypoxia adaptation and virulence and reveal new insights into SREBPs' complex role in infection site adaptation and fungal virulence.

  2. Altered Expression of Genes Implicated in Xylan Biosynthesis Affects Penetration Resistance against Powdery Mildew.

    Science.gov (United States)

    Chowdhury, Jamil; Lück, Stefanie; Rajaraman, Jeyaraman; Douchkov, Dimitar; Shirley, Neil J; Schwerdt, Julian G; Schweizer, Patrick; Fincher, Geoffrey B; Burton, Rachel A; Little, Alan

    2017-01-01

    Heteroxylan has recently been identified as an important component of papillae, which are formed during powdery mildew infection of barley leaves. Deposition of heteroxylan near the sites of attempted fungal penetration in the epidermal cell wall is believed to enhance the physical resistance to the fungal penetration peg and hence to improve pre-invasion resistance. Several glycosyltransferase (GT) families are implicated in the assembly of heteroxylan in the plant cell wall, and are likely to work together in a multi-enzyme complex. Members of key GT families reported to be involved in heteroxylan biosynthesis are up-regulated in the epidermal layer of barley leaves during powdery mildew infection. Modulation of their expression leads to altered susceptibility levels, suggesting that these genes are important for penetration resistance. The highest level of resistance was achieved when a GT43 gene was co-expressed with a GT47 candidate gene, both of which have been predicted to be involved in xylan backbone biosynthesis. Altering the expression level of several candidate heteroxylan synthesis genes can significantly alter disease susceptibility. This is predicted to occur through changes in the amount and structure of heteroxylan in barley papillae.

  3. Invasive fungal infections after natural disasters.

    Science.gov (United States)

    Benedict, Kaitlin; Park, Benjamin J

    2014-03-01

    The link between natural disasters and subsequent fungal infections in disaster-affected persons has been increasingly recognized. Fungal respiratory conditions associated with disasters include coccidioidomycosis, and fungi are among several organisms that can cause near-drowning pneumonia. Wound contamination with organic matter can lead to post-disaster skin and soft tissue fungal infections, notably mucormycosis. The role of climate change in the environmental growth, distribution, and dispersal mechanisms of pathogenic fungi is not fully understood; however, ongoing climate change could lead to increased disaster-associated fungal infections. Fungal infections are an often-overlooked clinical and public health issue, and increased awareness by health care providers, public health professionals, and community members regarding disaster-associated fungal infections is needed.

  4. The Spatial Organization of Glucosinolate Biosynthesis

    DEFF Research Database (Denmark)

    Nintemann, Sebastian

    cells is an open question. Likewise, it is not known how glucosinolate biosynthesis is orchestrated at the subcellular level. These open questions were addressed with several approaches in this project, with the aim of shedding light on the spatial organization of glucosinolate biosynthesis from...... between the individual classes of glucosinolates under constitutive and induced conditions and identified the source tissues of these defense compounds. Protein-protein interaction studies were carried out to investigate the subcellular organization of glucosinolate biosynthesis. We identified a family...

  5. Fungal Endocarditis: Update on Diagnosis and Management.

    Science.gov (United States)

    Pasha, Ahmed Khurshid; Lee, Justin Z; Low, See-Wei; Desai, Hem; Lee, Kwan S; Al Mohajer, Mayar

    2016-10-01

    Fungal endocarditis is an extremely debilitating disease associated with high morbidity and mortality. Candida spp. are the most common isolated organisms in fungal endocarditis. It is most prevalent in patients who are immunosuppressed and intravenous drug users. Most patients present with constitutional symptoms, which are indistinguishable from bacterial endocarditis, hence a high index of suspicion is required for pursuing diagnosis. Diagnosis of fungal endocarditis can be very challenging: most of the time, blood cultures are negative or take a long time to yield growth. Fungal endocarditis mandates an aggressive treatment strategy. A medical and surgical combined approach is the cornerstone of therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Monoterpene biosynthesis potential of plant subcellular compartments

    NARCIS (Netherlands)

    Dong, L.; Jongedijk, E.J.; Bouwmeester, H.J.; Krol, van der A.R.

    2016-01-01

    Subcellular monoterpene biosynthesis capacity based on local geranyl diphosphate (GDP) availability or locally boosted GDP production was determined for plastids, cytosol and mitochondria. A geraniol synthase (GES) was targeted to plastids, cytosol, or mitochondria. Transient expression in Nicotiana

  7. Method for determining heterologous biosynthesis pathways

    KAUST Repository

    Gao, Xin; Kuwahara, Hiroyuki; Alazmi, Meshari Saud; Cui, Xuefeng

    2017-01-01

    suitable pathways for the endogenous metabolism of a host organism because the efficacy of heterologous biosynthesis is affected by competing endogenous pathways. The present invention is called MRE (Metabolic Route Explorer), and it was conceived

  8. Transformation of Aspergillus parasiticus with a homologous gene (pyrG) involved in pyrimidine biosynthesis

    International Nuclear Information System (INIS)

    Skory, C.D.; Horng, J.S.; Pestka, J.J.; Linz, J.E.

    1990-01-01

    The lack of efficient transformation methods for aflatoxigenic Aspergillus parasiticus has been a major constraint for the study of aflatoxin biosynthesis at the genetic level. A transformation system with efficiencies of 30 to 50 stable transformants per μg of DNA was developed for A. parasiticus by using homologous pyrG gene. The pyrG gene from A. parasiticus was isolated by in situ plaque hybridization of a lambda genomic DNA library. Uridine auxotrophs of A. parasiticus ATCC 36537, a mutant blocked in aflatoxin biosynthesis, were isolated by selection on 5-fluoroorotic acid following nitrosoguanidine mutagenesis. Isolates with mutations in the pyrG gene resulting in elimination of orotidine monophosphate (OMP) decarboxylase activity were detected by assaying cell extracts for their ability to convert [ 14 C]OMP to [ 14 C]UMP. Transformation of A. parasiticus pyrG protoplasts with the homologous pyrG gene restored the fungal cells to prototrophy. Enzymatic analysis of cell extracts of transformant clones demonstrated that these extracts had the ability to convert [ 14 C]OMP to [ 14 C]UMP. Southern analysis of DNA purified from transformant clones indicated that both pUC19 vector sequences and pyrG sequences were integrated into the genome. The development of this pyrG transformation system should allow cloning of the aflatoxin-biosynthetic genes, which will be useful in studying the regulation of aflatoxin biosynthesis and may ultimately provide a means for controlling aflatoxin production in the field

  9. Fungus-mediated synthesis of gold nanoparticles and standardization of parameters for its biosynthesis.

    Science.gov (United States)

    Tidke, Pritish R; Gupta, Indarchand; Gade, Aniket K; Rai, Mahendra

    2014-12-01

    We report the extracellular biosynthesis of gold nanoparticles (AuNPs) using a fungus Fusarium acuminatum. Mycosynthesis of Au-NPs was carried out by challenging the fungal cells filtrate with HAuCl 4 solution (1 mM), as nanoparticles synthesizing enzyme secrete extracellularly by the fungi. The AuNPs were characterized with the help of UV-Visible spectrophotometer, Fourier Transform Infrared spectroscopy, Zeta Potential, X-ray diffraction (XRD) and Transmission electron microscopy (TEM). We observed absorbance peak in between 520 nm-550 nm corresponding to the surface plasmon absorbance of the gold nanoparticles. The nanoparticles synthesized in the present investigation were found to be capped by proteins. XRD results showed that the distinctive formation of crystalline gold nanoparticles in the solution. The spherical and polydispersed AuNPs in the range 8 to 28 nm with average size of 17 nm were observed by TEM analysis. We also standardized the parameters like the effect of pH, temperature and salt concentration on the biosynthesis of gold nanoparticles. It was found that acidic pH, 1 mM salt concentration and 37 (°)C temperature were found to be optimum for the synthesis of Au-NPs. Therefore, the present study introduces the easy, better and cheaper method for biosynthesis of AuNPs.

  10. Rapid extra-/intracellular biosynthesis of gold nanoparticles by the fungus Penicillium sp.

    Science.gov (United States)

    Du, Liangwei; Xian, Liang; Feng, Jia-Xun

    2011-03-01

    In this work, the fungus Penicillium was used for rapid extra-/intracellular biosynthesis of gold nanoparticles. AuCl4 - ions reacted with the cell filtrate of Penicillium sp. resulting in extracellular biosynthesis of gold nanoparticles within 1 min. Intracellular biosynthesis of gold nanoparticles was obtained by incubating AuCl4 - solution with fungal biomass for 8 h. The gold nanoparticles were characterized by means of visual observation, UV-Vis absorption spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The extracellular nanoparticles exhibited maximum absorbance at 545 nm in UV-Vis spectroscopy. The XRD spectrum showed Bragg reflections corresponding to the gold nanocrystals. TEM exhibited the formed spherical gold nanoparticles in the size range from 30 to 50 nm with an average size of 45 nm. SEM and TEM revealed that the intracellular gold nanoparticles were well dispersed on the cell wall and within the cell, and they are mostly spherical in shape with an average diameter of 50 nm. The presence of gold was confirmed by EDX analysis.

  11. Fungal transmission of plant viruses.

    Science.gov (United States)

    Campbell, R N

    1996-01-01

    Thirty soilborne viruses or virus-like agents are transmitted by five species of fungal vectors. Ten polyhedral viruses, of which nine are in the family Tombusviridae, are acquired in the in vitro manner and do not occur within the resting spores of their vectors, Olpidium brassicae and O. bornovanus. Fungal vectors for other viruses in the family should be sought even though tombusviruses are reputed to be soil transmitted without a vector. Eighteen rod-shaped viruses belonging to the furo- and bymovirus groups and to an unclassified group are acquired in the in vivo manner and survive within the resting spores of their vector, O. brassicae, Polymyxa graminis, P. betae, and Spongospora subterranea. The viral coat protein has an essential role in in vitro transmission. With in vivo transmission a site in the coat protein-read through protein (CP-RT) of beet necrotic yellow vein furovirus determines vector transmissibility as does a site in a similar 98-kDa polyprotein of barley mild mosaic bymovirus. The mechanisms by which virions move (or are moved) into and out of the protoplasm of zoospores or of thalli needs study.

  12. Optimal Fungal Space Searching Algorithms.

    Science.gov (United States)

    Asenova, Elitsa; Lin, Hsin-Yu; Fu, Eileen; Nicolau, Dan V; Nicolau, Dan V

    2016-10-01

    Previous experiments have shown that fungi use an efficient natural algorithm for searching the space available for their growth in micro-confined networks, e.g., mazes. This natural "master" algorithm, which comprises two "slave" sub-algorithms, i.e., collision-induced branching and directional memory, has been shown to be more efficient than alternatives, with one, or the other, or both sub-algorithms turned off. In contrast, the present contribution compares the performance of the fungal natural algorithm against several standard artificial homologues. It was found that the space-searching fungal algorithm consistently outperforms uninformed algorithms, such as Depth-First-Search (DFS). Furthermore, while the natural algorithm is inferior to informed ones, such as A*, this under-performance does not importantly increase with the increase of the size of the maze. These findings suggest that a systematic effort of harvesting the natural space searching algorithms used by microorganisms is warranted and possibly overdue. These natural algorithms, if efficient, can be reverse-engineered for graph and tree search strategies.

  13. [Iron and invasive fungal infection].

    Science.gov (United States)

    Álvarez, Florencio; Fernández-Ruiz, Mario; Aguado, José María

    2013-01-01

    Iron is an essential factor for both the growth and virulence of most of microorganisms. As a part of the innate (or nutritional) immune system, mammals have developed different mechanisms to store and transport this element in order to limit free iron bioavailability. To survive in this hostile environment, pathogenic fungi have specific uptake systems for host iron sources, one of the most important of which is based on the synthesis of siderophores-soluble, low-molecular-mass, high-affinity iron chelators. The increase in free iron that results from iron-overload conditions is a well-established risk factor for invasive fungal infection (IFI) such as mucormycosis or aspergillosis. Therefore, iron chelation may be an appealing therapeutic option for these infections. Nevertheless, deferoxamine -the first approved iron chelator- paradoxically increases the incidence of IFI, as it serves as a xeno-siderophore to Mucorales. On the contrary, the new oral iron chelators (deferiprone and deferasirox) have shown to exert a deleterious effect on fungal growth both in vitro and in animal models. The present review focuses on the role of iron metabolism in the pathogenesis of IFI and summarises the preclinical data, as well as the limited clinical experience so far, in the use of new iron chelators as treatment for mucormycosis and invasive aspergillosis. Copyright © 2012 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  14. Cellulose biosynthesis in higher plants

    Directory of Open Access Journals (Sweden)

    Krystyna Kudlicka

    2014-01-01

    Full Text Available Knowledge of the control and regulation of cellulose synthesis is fundamental to an understanding of plant development since cellulose is the primary structural component of plant cell walls. In vivo, the polymerization step requires a coordinated transport of substrates across membranes and relies on delicate orientations of the membrane-associated synthase complexes. Little is known about the properties of the enzyme complexes, and many questions about the biosynthesis of cell wall components at the cell surface still remain unanswered. Attempts to purify cellulose synthase from higher plants have not been successful because of the liability of enzymes upon isolation and lack of reliable in vitro assays. Membrane preparations from higher plant cells incorporate UDP-glucose into a glucan polymer, but this invariably turns out to be predominantly β -1,3-linked rather than β -1,4-linked glucans. Various hypotheses have been advanced to explain this phenomenon. One idea is that callose and cellulose-synthase systems are the same, but cell disruption activates callose synthesis preferentially. A second concept suggests that a regulatory protein as a part of the cellulose-synthase complex is rapidly degraded upon cell disruption. With new methods of enzyme isolation and analysis of the in vitro product, recent advances have been made in the isolation of an active synthase from the plasma membrane whereby cellulose synthase was separated from callose synthase.

  15. Biosynthesis of extracellular and intracellular gold nanoparticles by Aspergillus fumigatus and A. flavus.

    Science.gov (United States)

    Gupta, Saurabh; Bector, Shruti

    2013-05-01

    Green chemistry is a boon for the development of safe, stable and ecofriendly nanostructures using biological tools. The present study was carried out to explore the potential of selected fungal strains for biosynthesis of intra- and extracellular gold nanostructures. Out of the seven cultures, two fungal strains (SBS-3 and SBS-7) were selected on the basis of development of dark pink colour in cell free supernatant and fungal beads, respectively indicative of extra- and intracellular gold nanoparticles production. Both biomass associated and cell free gold nanoparticles were characterized using X-ray diffractogram (XRD) analysis and transmission electron microscopy (TEM). XRD analysis confirmed crystalline, face-centered cubic lattice of metallic gold nanoparticles along with average crystallite size. A marginal difference in average crystallite size of extracellular (17.76 nm) and intracellular (26 and 22 nm) Au-nanostructures was observed using Scherrer equation. In TEM, a variety of shapes (triangles, spherical, hexagonal) were observed in both extra- and intracellular nanoparticles. 18S rRNA gene sequence analysis by multiple sequence alignment (BLAST) indicated 99 % homology of SBS-3 to Aspergillus fumigatus with 99 % alignment coverage and 98 % homology of SBS-7 to Aspergillus flavus with 98 % alignment coverage respectively. Native-PAGE and activity staining further confirmed enzyme linked synthesis of gold nanoparticles.

  16. Fungal effector proteins: past, present and future

    NARCIS (Netherlands)

    Wit, de P.J.G.M.; Mehrabi, R.; Burg, van den H.A.; Stergiopoulos, I.

    2009-01-01

    The pioneering research of Harold Flor on flax and the flax rust fungus culminated in his gene-for-gene hypothesis. It took nearly 50 years before the first fungal avirulence (Avr) gene in support of his hypothesis was cloned. Initially, fungal Avr genes were identified by reverse genetics and

  17. A novel class of fungal lipoxygenases

    NARCIS (Netherlands)

    Heshof, R.; Jylhä, S.; Haarmann, T.; Jørgensen, A.L.W.; Dalsgaard, T.K.; Graaff, de L.H.

    2014-01-01

    Lipoxygenases (LOXs) are well-studied enzymes in plants and mammals. However, fungal LOXs are less studied. In this study, we have compared fungal LOX protein sequences to all known characterized LOXs. For this, a script was written using Shell commands to extract sequences from the NCBI database

  18. Fungal infection knowledge gap in Ethiopia

    African Journals Online (AJOL)

    EPHA USER33

    receiving immunosuppressive therapy, and patients with chronic obstructive lung disease (1). Fungi also play a role in allergic fungal disease such as allergic broncho- pulmonary Aspergilosis (ABPA) and chronic or deep tissue infections. The laboratory diagnosis of fungal infection starts with a simple potassium hydroxide.

  19. Clinical consideration of fungal paranasal sinusitis

    International Nuclear Information System (INIS)

    Okuni, Tsuyoshi; Asakura, Koji; Homma, Tomo; Kawaguchi, Ryuichi; Ishikawa, Tadataka; Yamazaki, Norikazu; Himi, Tetsuo

    2008-01-01

    Fungal paranasal sinusitis is included in the differential diagnosis of unilateral paranasal lesion. Recently the incidence of fungal paranasal sinusitis has been increasing. We reviewed 24 patients (9 males and 15 females) with fungal paranasal sinusitis treated at Muroran City Hospital between January 2001 and May 2006, and clinical presentation and CT findings with those of 56 patients (36 males and 20 females) with chronic unilateral sinusitis. Fungal sinusitis patients ranged in age from 45 to 87, and the average age was 65.9 years old. In contrast, the age of chronic sinusitis patients ranged from 24 to 83, and the average age was 54.4 years old. The chief complaint of both fungal sinusitis and chronic sinusitis included rhinorrhea, nasal obstruction and post nasal discharge. CT exam was performed in all patients. In 23 cases of paranasal fungal sinusitis and 54 cases of chronic sinusitis the findings involved the maxillary sinus. The most common observation (69.6%) was bone density within the affected sinus in fungal sinusitis. However, only 2 cases of chronic sinusitis (3.9%) showed calcification. All cases of fungal sinusitis were diagnosed by pathological examinations. Most cases were proved to be aspergillus, while only one case was mucor. We treated all cases surgically, 18 cases underwent Caldwell-Luc's procedure and 5 cases underwent endoscopic sinus surgery under local anesthesia. (author)

  20. Fungal cultivation on glass-beads

    DEFF Research Database (Denmark)

    Droce, Aida; Sørensen, Jens Laurids; Giese, Henriette

    Transcription of various bioactive compounds and enzymes are dependent on fungal cultivation method. In this study we cultivate Fusarium graminearum and Fusarium solani on glass-beads with liquid media in petri dishes as an easy and inexpensive cultivation method, that resembles in secondary...... metabolite production to agar-cultivation but with an easier and more pure RNA-extraction of total fungal mycelia....

  1. Histone Acetylation in Fungal Pathogens of Plants

    Directory of Open Access Journals (Sweden)

    Junhyun Jeon

    2014-03-01

    Full Text Available Acetylation of histone lysine residues occurs in different organisms ranging from yeast to plants and mammals for the regulation of diverse cellular processes. With the identification of enzymes that create or reverse this modification, our understanding on histone acetylation has expanded at an amazing pace during the last two decades. In fungal pathogens of plants, however, the importance of such modification has only just begun to be appreciated in the recent years and there is a dearth of information on how histone acetylation is implicated in fungal pathogenesis. This review covers the current status of research related to histone acetylation in plant pathogenic fungi and considers relevant findings in the interaction between fungal pathogens and host plants. We first describe the families of histone acetyltransferases and deacetylases. Then we provide the cases where histone acetylation was investigated in the context of fungal pathogenesis. Finally, future directions and perspectives in epigenetics of fungal pathogenesis are discussed.

  2. Soil fungal community responses to global changes

    DEFF Research Database (Denmark)

    Haugwitz, Merian Skouw

    Global change will affect the functioning and structure of terrestrial ecosystems and since soil fungi are key players in organic matter decomposition and nutrient turnover, shifts in fungal community composition might have a strong impact on soil functioning. The main focus of this thesis...... was therefore to investigate the impact of global environmental changes on soil fungal communities in a temperate and subartic heath ecosystem. The objective was further to determine global change effects on major functional groups of fungi and analyze the influence of fungal community changes on soil carbon...... and nutrient availability and storage. By combining molecular methods such as 454 pyrosequencing and quantitative PCR of fungal ITS amplicons with analyses of soil enzymes, nutrient pools of carbon, nitrogen and phosphorus we were able to characterize soil fungal communities as well as their impact on nutrient...

  3. INCIDENCE OF FUNGAL ELEMENTS IN SINONASAL POLYPOSIS

    Directory of Open Access Journals (Sweden)

    Santhosh G. S

    2016-12-01

    Full Text Available BACKGROUND Nasal polyposis is a disease entity characterised by formation of pseudoedema of sinonasal mucus membrane progressing to form polyps. It presents clinically with nasal obstruction and fleshy masses in the nasal cavity. The nasal mucosa reacts to formation of polypi in allergic fungal sinusitis also. The present study is an attempt to demonstrate possible fungal elements from the polypi removed during surgery by KOH study and HPE study. The aim of the study is to find out the incidence of fungal elements in sinonasal polyposis. MATERIALS AND METHODS 50 patients attending the ENT OPD for nasal obstruction and showing polypi on anterior rhinoscopy were selected. All the patients were subjected to surgery and specimens collected were subjected to KOH study and histopathology to demonstrate fungal elements. RESULTS Among 50 patients, the age range was from 9-57 years; mean age- 36.46 years. The male-to-female ratio was 1.5:1. Deviated nasal septum was found in 38% of patients. Among the unilateral cases, 47% were antrochoanal polyps and 53% were ethmoid polyps. Out of 50 patients, only 3 specimens were positive for fungal elements with KOH study and only 2 cases with fungal culture. Thus, the incidence of fungal elements in sinonasal polyposis was 6%. CONCLUSION The incidence of fungal elements in sinonasal polyposis was 6%. Histopathological examination of polypectomy specimen was negative for invasive fungal disease and showed inflammatory changes only. There is no difference in the detection of the presence of fungal by two methods.

  4. Identification of two aflatrem biosynthesis gene loci in Aspergillus flavus and metabolic engineering of Penicillium paxilli to elucidate their function.

    Science.gov (United States)

    Nicholson, Matthew J; Koulman, Albert; Monahan, Brendon J; Pritchard, Beth L; Payne, Gary A; Scott, Barry

    2009-12-01

    Aflatrem is a potent tremorgenic toxin produced by the soil fungus Aspergillus flavus, and a member of a structurally diverse group of fungal secondary metabolites known as indole-diterpenes. Gene clusters for indole-diterpene biosynthesis have recently been described in several species of filamentous fungi. A search of Aspergillus complete genome sequence data identified putative aflatrem gene clusters in the genomes of A. flavus and Aspergillus oryzae. In both species the genes for aflatrem biosynthesis cluster at two discrete loci; the first, ATM1, is telomere proximal on chromosome 5 and contains a cluster of three genes, atmG, atmC, and atmM, and the second, ATM2, is telomere distal on chromosome 7 and contains five genes, atmD, atmQ, atmB, atmA, and atmP. Reverse transcriptase PCR in A. flavus demonstrated that aflatrem biosynthesis transcript levels increased with the onset of aflatrem production. Transfer of atmP and atmQ into Penicillium paxilli paxP and paxQ deletion mutants, known to accumulate paxilline intermediates paspaline and 13-desoxypaxilline, respectively, showed that AtmP is a functional homolog of PaxP and that AtmQ utilizes 13-desoxypaxilline as a substrate to synthesize aflatrem pathway-specific intermediates, paspalicine and paspalinine. We propose a scheme for aflatrem biosynthesis in A. flavus based on these reconstitution experiments in P. paxilli and identification of putative intermediates in wild-type cultures of A. flavus.

  5. Chapter 8: Invasive fungal rhinosinusitis.

    Science.gov (United States)

    Duggal, Praveen; Wise, Sarah K

    2013-01-01

    Invasive fungal rhinosinusitis (IFRS) is a disease of the paranasal sinuses and nasal cavity that typically affects immunocompromised patients in the acute fulminant form. Early symptoms can often mimic rhinosinusitis, while late symptoms can cause significant morbidity and mortality. Swelling and mucosal thickening can quickly progress to pale or necrotic tissue in the nasal cavity and sinuses, and the disease can rapidly spread and invade the palate, orbit, cavernous sinus, cranial nerves, skull base, carotid artery, and brain. IFRS can be life threatening if left undiagnosed or untreated. While the acute fulminant form of IFRS is the most rapidly progressive and destructive, granulomatous and chronic forms also exist. Diagnosis of IFRS often mandates imaging studies in conjunction with clinical, endoscopic, and histopathological examination. Treatment of IFRS consists of reversing the underlying immunosuppression, antifungal therapy, and aggressive surgical debridement. With early diagnosis and treatment, IFRS can be treated and increase patient survival.

  6. Fungal Cytochrome P450s and the P450 Complement (CYPome of Fusarium graminearum

    Directory of Open Access Journals (Sweden)

    Jiyoung Shin

    2018-03-01

    Full Text Available Cytochrome P450s (CYPs, heme-containing monooxygenases, play important roles in a wide variety of metabolic processes important for development as well as biotic/trophic interactions in most living organisms. Functions of some CYP enzymes are similar across organisms, but some are organism-specific; they are involved in the biosynthesis of structural components, signaling networks, secondary metabolisms, and xenobiotic/drug detoxification. Fungi possess more diverse CYP families than plants, animals, or bacteria. Various fungal CYPs are involved in not only ergosterol synthesis and virulence but also in the production of a wide array of secondary metabolites, which exert toxic effects on humans and other animals. Although few studies have investigated the functions of fungal CYPs, a recent systematic functional analysis of CYP genes in the plant pathogen Fusarium graminearum identified several novel CYPs specifically involved in virulence, asexual and sexual development, and degradation of xenobiotics. This review provides fundamental information on fungal CYPs and a new platform for further metabolomic and biochemical studies of CYPs in toxigenic fungi.

  7. Fungal infection in organ transplant patients.

    Science.gov (United States)

    Hong, Wei; Wen, Hai; Liao, Wanqing

    2003-09-01

    To review the characteristics and evolution of the fungal spectrum, and the risk factors causing fungal infection, and to make progress in diagnosing fungal infection after organ transplantation. An English-language literature search (MEDLINE 1990 - 2000) and bibliographic review of textbooks and review articles. Twenty-three articles were selected from the literature that specifically addressed the stated purpose. Fungal infections in organ transplant patients were generally divided into two types: (1) disseminated primary or reactivation infection with one of the geographically restricted systemic mycoses; (2) opportunistic infection by fungal species that rarely cause invasive infection in normal hosts. The risk factors of fungal infection after a transplant can be evaluated and predicted according to the organ recipient's conditions before, during and after the transplant. Progress in early diagnostic methods during the past 10 years has mainly revolved around two aspects, culture and non-culture. It is important to undertake a systemic evaluation on the condition of the organ recipient before, during and after a transplant; should any risk factor for fungal infection be suspected, diagnosis should be made as early as possible by employing mycological techniques including culture and non-culture methods.

  8. Biosynthesis and function of chondroitin sulfate.

    Science.gov (United States)

    Mikami, Tadahisa; Kitagawa, Hiroshi

    2013-10-01

    Chondroitin sulfate proteoglycans (CSPGs) are principal pericellular and extracellular components that form regulatory milieu involving numerous biological and pathophysiological phenomena. Diverse functions of CSPGs can be mainly attributed to structural variability of their polysaccharide moieties, chondroitin sulfate glycosaminoglycans (CS-GAG). Comprehensive understanding of the regulatory mechanisms for CS biosynthesis and its catabolic processes is required in order to understand those functions. Here, we focus on recent advances in the study of enzymatic regulatory pathways for CS biosynthesis including successive modification/degradation, distinct CS functions, and disease phenotypes that have been revealed by perturbation of the respective enzymes in vitro and in vivo. Fine-tuned machineries for CS production/degradation are crucial for the functional expression of CS chains in developmental and pathophysiological processes. Control of enzymes responsible for CS biosynthesis/catabolism is a potential target for therapeutic intervention for the CS-associated disorders. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Fungal colonization of air-conditioning systems

    Directory of Open Access Journals (Sweden)

    Ljaljević-Grbić Milica

    2008-01-01

    Full Text Available Fungi have been implicated as quantitatively the most important bioaerosol component of indoor air associated with contaminated air-conditioning systems. rarely, indoor fungi may cause human infections, but more commonly allergenic responses ranging from pneumonitis to asthma-like symptoms. From all air conditioner filters analyzed, 16 fungal taxa were isolated and identified. Aspergillus fumigatus causes more lethal infections worldwide than any other mold. Air-conditioning filters that adsorb moisture and volatile organics appear to provide suitable substrates for fungal colonization. It is important to stress that fungal colonization of air-conditioning systems should not be ignored, especially in hospital environments.

  10. Fungal infections in neutropenic cancer patients

    International Nuclear Information System (INIS)

    Parvez, T.

    2003-01-01

    Invasive fungal infections are important causes of morbidity and mortality in cancer patients with prolonged neutropenia following chemotherapy. Recent trends indicate a change toward infections by Aspergillus species, non-albicans species of Candida, and previously uncommon fungal pathogens. These have decreased susceptibility to current antifungal agents. In the last decade there has been much effort to find solutions for these changing trends. This article reviews current approaches to prevention and treatment of opportunistic fungal infections in postchemotherapy neutropenic patients and discussion future antifungal approaches and supportive methods. (author)

  11. Triterpenoid biosynthesis in Euphorbia lathyris latex

    International Nuclear Information System (INIS)

    Hawkins, D.R.

    1987-11-01

    The structures of triterpenols, not previously been known, from Euphorbia lathyris latex are reported. A method for quantifying very small amounts of these compounds was developed. Concerning the biochemistry of the latex, no exogenous cofactors were required for the biosynthesis and the addition of compounds such as NADPAH and ATP do not stimulate the biosynthesis. The addition of DTE or a similar anti-oxidant was found to help reduce the oxidation of the latex, thus increasing the length of time that the latex remains active. The requirement of a divalent cation and the preference for Mn in the pellet was observed. The effect of several inhibitors on the biosynthesis of the triterpenoids was examined. Mevinolin was found to inhibit the biosynthesis of the triterpenoids from acetate, but not mevalonate. A dixon plot of the inhibition of acetate incorporation showed an I 50 concentration of 3.2 μM. Fenpropimorph was found to have little or no effect on the biosynthesis. Tridemorph was found to inhibit the biosynthesis of all of the triterpenoids with an I 50 of 4 μM. It was also observed that the cyclopropyl containing triterpenols, cycloartenol and 24-methylenecycloartenol were inhibited much more strongly than those containing an 8-9 double bond, lanosterol and 24-methylenelanosterol. The evidence indicates, but does not definetely prove, that lanosterol and 24-methylenelanosterol are not made from cycloartenol and 24-methylenecycloartenol via a ring-opening enzyme such as cycloeucalenol-obtusifoliol isomerase. The possibilty that cycloartenol is made via lanosterol was investigated by synthesizing 4-R-4- 3 H-mevalonic acid and incubating latex with a mixture of this and 14 C-mevalonic acid. From the 3 H/ 14 C ratio it was shown that cycloartenol and 24-methylenecycloartenol are not made via an intermediate containing as 8-9 double bond. 88 refs., 15 figs., 30 tabs

  12. Triterpenoid biosynthesis in Euphorbia lathyris latex

    Energy Technology Data Exchange (ETDEWEB)

    Hawkins, D.R.

    1987-11-01

    The structures of triterpenols, not previously been known, from Euphorbia lathyris latex are reported. A method for quantifying very small amounts of these compounds was developed. Concerning the biochemistry of the latex, no exogenous cofactors were required for the biosynthesis and the addition of compounds such as NADPAH and ATP do not stimulate the biosynthesis. The addition of DTE or a similar anti-oxidant was found to help reduce the oxidation of the latex, thus increasing the length of time that the latex remains active. The requirement of a divalent cation and the preference for Mn in the pellet was observed. The effect of several inhibitors on the biosynthesis of the triterpenoids was examined. Mevinolin was found to inhibit the biosynthesis of the triterpenoids from acetate, but not mevalonate. A dixon plot of the inhibition of acetate incorporation showed an I/sub 50/ concentration of 3.2 ..mu..M. Fenpropimorph was found to have little or no effect on the biosynthesis. Tridemorph was found to inhibit the biosynthesis of all of the triterpenoids with an I/sub 50/ of 4 ..mu..M. It was also observed that the cyclopropyl containing triterpenols, cycloartenol and 24-methylenecycloartenol were inhibited much more strongly than those containing an 8-9 double bond, lanosterol and 24-methylenelanosterol. The evidence indicates, but does not definetely prove, that lanosterol and 24-methylenelanosterol are not made from cycloartenol and 24-methylenecycloartenol via a ring-opening enzyme such as cycloeucalenol-obtusifoliol isomerase. The possibilty that cycloartenol is made via lanosterol was investigated by synthesizing 4-R-4-/sup 3/H-mevalonic acid and incubating latex with a mixture of this and /sup 14/C-mevalonic acid. From the /sup 3/H//sup 14/C ratio it was shown that cycloartenol and 24-methylenecycloartenol are not made via an intermediate containing as 8-9 double bond. 88 refs., 15 figs., 30 tabs.

  13. Convergent Evolution of Ergothioneine Biosynthesis in Cyanobacteria.

    Science.gov (United States)

    Liao, Cangsong; Seebeck, Florian P

    2017-11-02

    Biosynthesis of N-α-trimethyl-2-thiohistidine (ergothioneine) is a frequent trait in cyanobacteria. This sulfur compound may provide essential relief from oxidative stress related to oxygenic photosynthesis. The central steps in ergothioneine biosynthesis are catalyzed by a histidine methyltransferase and an iron-dependent sulfoxide synthase. In this report, we present evidence that some cyanobacteria recruited and adapted a sulfoxide synthase from a different biosynthetic pathway to make ergothioneine. The discovery of a second origin of ergothioneine production underscores the physiological importance of this metabolite and highlights the evolutionary malleability of the thiohistidine biosynthetic machinery. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Method for determining heterologous biosynthesis pathways

    KAUST Repository

    Gao, Xin

    2017-08-10

    The present invention relates to a method and system for dynamically analyzing, determining, predicting and displaying ranked suitable heterologous biosynthesis pathways for a specified host. The present invention addresses the problem of finding suitable pathways for the endogenous metabolism of a host organism because the efficacy of heterologous biosynthesis is affected by competing endogenous pathways. The present invention is called MRE (Metabolic Route Explorer), and it was conceived and developed to systematically and dynamically search for, determine, analyze, and display promising heterologous pathways while considering competing endogenous reactions in a given host organism.

  15. Nucleoside antibiotics: biosynthesis, regulation, and biotechnology.

    Science.gov (United States)

    Niu, Guoqing; Tan, Huarong

    2015-02-01

    The alarming rise in antibiotic-resistant pathogens has coincided with a decline in the supply of new antibiotics. It is therefore of great importance to find and create new antibiotics. Nucleoside antibiotics are a large family of natural products with diverse biological functions. Their biosynthesis is a complex process through multistep enzymatic reactions and is subject to hierarchical regulation. Genetic and biochemical studies of the biosynthetic machinery have provided the basis for pathway engineering and combinatorial biosynthesis to create new or hybrid nucleoside antibiotics. Dissection of regulatory mechanisms is leading to strategies to increase the titer of bioactive nucleoside antibiotics. Copyright © 2014. Published by Elsevier Ltd.

  16. The expanding universe of alkaloid biosynthesis.

    Science.gov (United States)

    De Luca, V; Laflamme, P

    2001-06-01

    Characterization of many of the major gene families responsible for the generation of central intermediates and for their decoration, together with the development of large genomics and proteomics databases, has revolutionized our capability to identify exotic and interesting natural-product pathways. Over the next few years, these tools will facilitate dramatic advances in our knowledge of the biosynthesis of alkaloids, which will far surpass that which we have learned in the past 50 years. These tools will also be exploited for the rapid characterization of regulatory genes, which control the development of specialized cell factories for alkaloid biosynthesis.

  17. Biosynthesis of silver nanoparticles by Aspergillus niger , Fusarium ...

    African Journals Online (AJOL)

    ... scanning electron microscope (SEM). Results indicate the synthesis of silver nanoparticles in the reaction mixture. The synthesis of nanoparticles would be suitable for developing a microbial nanotechnology biosynthesis process for mass scale production. Keywords: Silver nanoparticles, biosynthesis, fungi, Aspergillus.

  18. Sterol Biosynthesis Pathway as Target for Anti-trypanosomatid Drugs

    Directory of Open Access Journals (Sweden)

    Wanderley de Souza

    2009-01-01

    Full Text Available Sterols are constituents of the cellular membranes that are essential for their normal structure and function. In mammalian cells, cholesterol is the main sterol found in the various membranes. However, other sterols predominate in eukaryotic microorganisms such as fungi and protozoa. It is now well established that an important metabolic pathway in fungi and in members of the Trypanosomatidae family is one that produces a special class of sterols, including ergosterol, and other 24-methyl sterols, which are required for parasitic growth and viability, but are absent from mammalian host cells. Currently, there are several drugs that interfere with sterol biosynthesis (SB that are in use to treat diseases such as high cholesterol in humans and fungal infections. In this review, we analyze the effects of drugs such as (a statins, which act on the mevalonate pathway by inhibiting HMG-CoA reductase, (b bisphosphonates, which interfere with the isoprenoid pathway in the step catalyzed by farnesyl diphosphate synthase, (c zaragozic acids and quinuclidines, inhibitors of squalene synthase (SQS, which catalyzes the first committed step in sterol biosynthesis, (d allylamines, inhibitors of squalene epoxidase, (e azoles, which inhibit C14α-demethylase, and (f azasterols, which inhibit Δ24(25-sterol methyltransferase (SMT. Inhibition of this last step appears to have high selectivity for fungi and trypanosomatids, since this enzyme is not found in mammalian cells. We review here the IC50 values of these various inhibitors, their effects on the growth of trypanosomatids (both in axenic cultures and in cell cultures, and their effects on protozoan structural organization (as evaluted by light and electron microscopy and lipid composition. The results show that the mitochondrial membrane as well as the membrane lining the protozoan cell body and flagellum are the main targets. Probably as a consequence of these primary effects, other important changes take

  19. PNNL Fungal Biotechnology Core DOE-OBP Project

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Scott E.; Bruno, Kenneth S.; Butcher, Mark G.; Collett, James R.; Culley, David E.; Dai, Ziyu; Magnuson, Jon K.; Panisko, Ellen A.

    2009-11-30

    In 2009, we continued to address barriers to fungal fermentation in the primary areas of morphology control, genomics, proteomics, fungal hyperproductivity, biomass-to-products via fungal based consolidated bioprocesses, and filamentous fungal ethanol. “Alternative renewable fuels from fungi” was added as a new subtask. Plans were also made to launch a new advanced strain development subtask in FY2010.

  20. Complete genome sequence of Bacillus velezensis M75, a biocontrol agent against fungal plant pathogens, isolated from cotton waste.

    Science.gov (United States)

    Kim, Sang Yoon; Lee, Sang Yeob; Weon, Hang-Yeon; Sang, Mee Kyung; Song, Jaekyeong

    2017-01-10

    Bacillus species have been widely used as biological control agents in agricultural fields due to their ability to suppress plant pathogens. Bacillus velezensis M75 was isolated from cotton waste used for mushroom cultivation in Korea, and was found to be antagonistic to fungal plant pathogens. Here, we report the complete genome sequence of the M75 strain, which has a 4,007,450-bp single circular chromosome with 3921 genes and a G+C content of 46.60%. The genome contained operons encoding various non-ribosomal peptide synthetases and polyketide synthases, which are responsible for the biosynthesis of secondary metabolites. Our results will provide a better understanding of the genome of B. velezensis strains for their application as biocontrol agents against fungal plant pathogens in agricultural fields. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. HIV/AIDS and Fungal Infections

    Science.gov (United States)

    ... Environmental Diseases Mycotic Diseases Branch People living with HIV/AIDS Recommend on Facebook Tweet Share Compartir As ... Page Preventing fungal infections in people living with HIV/AIDS Fungi are difficult to avoid because they ...

  2. Postharvest fungal deterioration of tomato ( Lycopersicum ...

    African Journals Online (AJOL)

    Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives ... tomatoes and pepper were sourced from Mile 12 Market in Lagos state. ... the ingestion of mycotoxins that are usually associated with fungal species), ...

  3. Fungal rhino sinusitisin in tehran, iran

    NARCIS (Netherlands)

    Nazeri, M.; Hashemi, S.J.; Ardehali, M.; Rezaei, S.; Seyedmousavi, S.; Zareei, M.; Hosseinjani, E.

    2015-01-01

    BACKGROUND: Fungal rhino sinusitis (FRS) is an important infection of para nasal sinuses, which encompasses two main categories; invasive and noninvasive forms according to histopathological findings. Aspergillus spp are the most common species isolated from noninvasive form, while Mucorales are

  4. Zoosporic fungal parasites of marine biota

    Digital Repository Service at National Institute of Oceanography (India)

    RaghuKumar, C.

    laboratory media. In such instances, a detailed and careful examination of the disease symptoms and the endobiotic fungal parasites is to be recorded. Maintaining dual culture of the healthy and infected host also helps to fulfill these postulates partially....

  5. Organ Transplant Patients and Fungal Infections

    Science.gov (United States)

    ... are mild skin rashes, but others can be deadly, like fungal pneumonia. Because of this, it’s important ... the environment. Fungi live outdoors in soil, on plants, trees, and other vegetation. They are also on ...

  6. Air Contamination With Fungals In Museum

    Science.gov (United States)

    Scarlat, Iuliana; Haiducu, Maria; Stepa, Raluca

    2015-07-01

    The aim of the studies was to determine the level and kind of fungal contamination of air in museum, deposits patrimony, restoration and conservation laboratories and their effects on health of workers. Microbiological air purity was measured with a SAS-100 Surface Air System impactor. The fungal contamination was observed in all 54 rooms where we made determinations. The highest levels of fungal were recorded at rooms with hygroscopic patrimony objects, eg carpets, chairs, upholstered chairs, books etc. The most species identified included under common allergens: Aspergillus, Penicillium, and Mucor. There fungal species belonging to the genus identified in this study, can trigger serious diseases museum workers, such as for example Aspergillus fumigatus, known allergies and toxic effects that may occur. In some places of the museum, occupational exposure limit values to fungi present in the air in the work environment, recommended by the specialized literature, have been overcome.

  7. Fungal keratitis - improving diagnostics by confocal microscopy

    DEFF Research Database (Denmark)

    Nielsen, Esben; Heegaard, S; Prause, J U

    2013-01-01

    Purpose: Introducing a simple image grading system to support the interpretation of in vivo confocal microscopy (IVCM) images in filamentous fungal keratitis. Setting: Clinical and confocal studies took place at the Department of Ophthalmology, Aarhus University Hospital, Denmark. Histopathological...... analysis was performed at the Eye Pathology Institute, Department of Neuroscience and Pharmacology, University of Copenhagen, Denmark. Methods: A recent series of consecutive patients with filamentous fungal keratitis is presented to demonstrate the results from in-house IVCM. Based upon our experience...... with IVCM and previously published images, we composed a grading system for interpreting IVCM images of filamentous fungal keratitis. Results: A recent case series of filamentous fungal keratitis from 2011 to 2012 was examined. There were 3 male and 3 female patients. Mean age was 44.5 years (range 12...

  8. Human Fungal Pathogens of Mucorales and Entomophthorales.

    Science.gov (United States)

    Mendoza, Leonel; Vilela, Raquel; Voelz, Kerstin; Ibrahim, Ashraf S; Voigt, Kerstin; Lee, Soo Chan

    2014-11-06

    In recent years, we have seen an increase in the number of immunocompromised cohorts as a result of infections and/or medical conditions, which has resulted in an increased incidence of fungal infections. Although rare, the incidence of infections caused by fungi belonging to basal fungal lineages is also continuously increasing. Basal fungal lineages diverged at an early point during the evolution of the fungal lineage, in which, in a simplified four-phylum fungal kingdom, Zygomycota and Chytridiomycota belong to the basal fungi, distinguishing them from Ascomycota and Basidiomycota. Currently there are no known human infections caused by fungi in Chytridiomycota; only Zygomycotan fungi are known to infect humans. Hence, infections caused by zygomycetes have been called zygomycosis, and the term "zygomycosis" is often used as a synonym for "mucormycosis." In the four-phylum fungal kingdom system, Zygomycota is classified mainly based on morphology, including the ability to form coenocytic (aseptated) hyphae and zygospores (sexual spores). In the Zygomycota, there are 10 known orders, two of which, the Mucorales and Entomophthorales, contain species that can infect humans, and the infection has historically been known as zygomycosis. However, recent multilocus sequence typing analyses (the fungal tree of life [AFTOL] project) revealed that the Zygomycota forms not a monophyletic clade but instead a polyphyletic clade, whereas Ascomycota and Basidiomycota are monophyletic. Thus, the term "zygomycosis" needed to be further specified, resulting in the terms "mucormycosis" and "entomophthoramycosis." This review covers these two different types of fungal infections. Copyright © 2015 Cold Spring Harbor Laboratory Press; all rights reserved.

  9. Burden of fungal infections in Senegal.

    Science.gov (United States)

    Badiane, Aida S; Ndiaye, Daouda; Denning, David W

    2015-10-01

    Senegal has a high rate of tuberculosis and a low HIV seropositivity rate and aspergilloma, life-threatening fungal infections, dermatophytosis and mycetoma have been reported in this study. All published epidemiology papers reporting fungal infection rates from Senegal were identified. Where no data existed, we used specific populations at risk and fungal infection frequencies in each to estimate national incidence or prevalence. The results show that tinea capitis is common being found in 25% of children, ~1.5 million. About 191,000 Senegalese women get recurrent vaginal thrush, ≥4 times annually. We estimate 685 incident cases of chronic pulmonary aspergillosis (CPA) following TB and prevalence of 2160 cases. Asthma prevalence in adults varies from 3.2% to 8.2% (mean 5%); 9976 adults have allergic bronchopulmonary aspergillosis (ABPA) and 13,168 have severe asthma with fungal sensitisation (SAFS). Of the 59,000 estimated HIV-positive patients, 366 develop cryptococcal meningitis; 1149 develop Pneumocystis pneumonia and 1946 develop oesophageal candidiasis, in which oral candidiasis (53%) and dermatophytosis (16%) are common. Since 2008-2010, 113 cases of mycetoma were diagnosed. In conclusion, we estimate that 1,743,507 (12.5%) people in Senegal suffer from a fungal infection, excluding oral candidiasis, fungal keratitis, invasive candidiasis or aspergillosis. Diagnostic and treatment deficiencies should be rectified to allow epidemiological studies. © 2015 Blackwell Verlag GmbH.

  10. Combinatorial biosynthesis of medicinal plant secondary metabolites

    NARCIS (Netherlands)

    Julsing, Mattijs K.; Koulman, Albert; Woerdenbag, Herman J.; Quax, Wim J.; Kayser, Oliver

    2006-01-01

    Combinatorial biosynthesis is a new tool in the generation of novel natural products and for the production of rare and expensive natural products. The basic concept is combining metabolic pathways in different organisms on a genetic level. As a consequence heterologous organisms provide precursors

  11. Peroxidase enzymes regulate collagen extracellular matrix biosynthesis.

    Science.gov (United States)

    DeNichilo, Mark O; Panagopoulos, Vasilios; Rayner, Timothy E; Borowicz, Romana A; Greenwood, John E; Evdokiou, Andreas

    2015-05-01

    Myeloperoxidase and eosinophil peroxidase are heme-containing enzymes often physically associated with fibrotic tissue and cancer in various organs, without any direct involvement in promoting fibroblast recruitment and extracellular matrix (ECM) biosynthesis at these sites. We report herein novel findings that show peroxidase enzymes possess a well-conserved profibrogenic capacity to stimulate the migration of fibroblastic cells and promote their ability to secrete collagenous proteins to generate a functional ECM both in vitro and in vivo. Mechanistic studies conducted using cultured fibroblasts show that these cells are capable of rapidly binding and internalizing both myeloperoxidase and eosinophil peroxidase. Peroxidase enzymes stimulate collagen biosynthesis at a post-translational level in a prolyl 4-hydroxylase-dependent manner that does not require ascorbic acid. This response was blocked by the irreversible myeloperoxidase inhibitor 4-amino-benzoic acid hydrazide, indicating peroxidase catalytic activity is essential for collagen biosynthesis. These results suggest that peroxidase enzymes, such as myeloperoxidase and eosinophil peroxidase, may play a fundamental role in regulating the recruitment of fibroblast and the biosynthesis of collagen ECM at sites of normal tissue repair and fibrosis, with enormous implications for many disease states where infiltrating inflammatory cells deposit peroxidases. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  12. Biosynthesis of polyhydroxyalkanotes in wildtype yeasts | Desuoky ...

    African Journals Online (AJOL)

    Biosynthesis of the biodegradable polymers polyhydroxyalkanotes (PHAs) are studied extensively in wild type and genetically modified prokaryotic cells, however the content and structure of PHA in wild type yeasts are not well documented. The purpose of this study was to screen forty yeast isolates collected from different ...

  13. Metabolic engineering for improved heterologous terpenoid biosynthesis

    NARCIS (Netherlands)

    Ryden, A.; Melillo, E.; Czepnik, M.; Kayser, O.

    Terpenoids belong to the largest class of natural compounds and are produced in all living organisms. The isoprenoid skeleton is based on assembling of C5 building blocks, but the biosynthesis of a great variety of terpenoids ranging from monoterpenoids to polyterpenoids is not fully understood

  14. Biosynthesis of silver nanoparticles synthesized by Aspergillus

    Indian Academy of Sciences (India)

    In the present study, biosynthesis of silver nanoparticles and its antioxidant, antimicrobial and cytotoxic activities were investigated. Silver nanoparticles were extracellularly synthesized using Aspergillus flavus and the formation of nanoparticles was observed after 72 h of incubation. The results recorded from colour ...

  15. Biosynthesis of furanochromones in Pimpinella monoica

    Indian Academy of Sciences (India)

    polyketide origin of their aromatic and pyrone rings while the furan ring originates via an acetate-mevalonate pathway. The plant also utilises glycine and leucine as substrate via acetate. Biotransformation of 3-H-visnagin to (6) but not to (2) was also observed. Keywords. Biosynthesis; furochromones; polyketide origin; ...

  16. Rapid biosynthesis and characterization of silver nanoparticles: an assessment of antibacterial and antimycotic activity

    Science.gov (United States)

    Kanawaria, Sajjan Kumar; Sankhla, Aryan; Jatav, Pradeep Kumar; Yadav, Raghvendra Singh; Verma, Kumar Sambhav; Velraj, Parthiban; Kachhwaha, Sumita; Kothari, Shanker Lal

    2018-04-01

    Bioassisted synthesis provides a facile, convenient, and promising approach to produce many inorganic nanostructures. Herein, we report a rapid biosynthesis of silver nanoparticles (AgNPs) using Thuja occidentalis (L.) leaf extract with an emphasis on their antibacterial and antimycotic activity. Interestingly, the synthesis of AgNPs was completed in a short duration of 35-40 min. The electron micrographs showed AgNPs with particles Bacillus subtilis. An AgNP solution with 30 µg/ml concentration arrested the growth of bacterial strains making a zone of inhibition > 15 mm. The antimycotic activity against Aspergillus niger, Fusarium spp., and Alternaria alternata species increased monotonically with nanoparticle concentration in the growth media. A 10 ppm solution of AgNP was detrimental to fungal growth. Thus, the technique provides an avenue to synthesize antibiotic AgNPs without use of other external agents.

  17. Biosynthesis of size-controlled gold nanoparticles using fungus, Penicillium sp.

    Science.gov (United States)

    Zhang, Xiaorong; He, Xiaoxiao; Wang, Kemin; Wang, Yonghong; Li, Huimin; Tan, Weihong

    2009-10-01

    The unique optoelectronic and physicochemical properties of gold nanoparticles are significantly dependent on the particle size, shape and structure. In this paper, biosynthesis of size-controlled gold nanoparticles using fungus Penicillium sp. is reported. Fungus Penicillium sp. could successfully bioreduce and nucleate AuCl4(-) ions, and lead to the assembly and formation of intracellular Au nanoparticles with spherical morphology and good monodispersity after exposure to HAuCl4 solution. Reaction temperature, as an important physiological parameter for fungus Penicillium sp. growth, could significantly control the size of the biosynthesized Au nanoparticles. The biological compositions and FTIR spectra analysis of fungus Penicillium sp. exposed to HAuCl4 solution indicated the intracellular reducing sugar played an important role in the occurrence of intracellular reduction of AuCl4(-) ions and the growth of gold nanoparticles. Furthermore, the intracellular gold nanoparticles could be easily separated from the fungal cell lysate by ultrasonication and centrifugation.

  18. Growth in rice cells requires de novo purine biosynthesis by the blast fungus Magnaporthe oryzae

    Science.gov (United States)

    Fernandez, Jessie; Yang, Kuan Ting; Cornwell, Kathryn M.; Wright, Janet D.; Wilson, Richard A.

    2013-01-01

    Increasing incidences of human disease, crop destruction and ecosystem perturbations are attributable to fungi and threaten socioeconomic progress and food security on a global scale. The blast fungus Magnaporthe oryzae is the most devastating pathogen of cultivated rice, but its metabolic requirements in the host are unclear. Here we report that a purine-requiring mutant of M. oryzae could develop functional appressoria, penetrate host cells and undergo the morphogenetic transition to elaborate bulbous invasive hyphae from primary hyphae, but further in planta growth was aborted. Invasive hyphal growth following rice cell ingress is thus dependent on de novo purine biosynthesis by the pathogen and, moreover, plant sources of purines are neither available to the mutant nor required by the wild type during the early biotrophic phase of infection. This work provides new knowledge about the metabolic interface between fungus and host that might be applicable to other important intracellular fungal pathogens. PMID:23928947

  19. Penicillium expansum (compatible) and Penicillium digitatum (non-host) pathogen infection differentially alter ethylene biosynthesis in apple fruit.

    Science.gov (United States)

    Vilanova, Laura; Vall-Llaura, Núria; Torres, Rosario; Usall, Josep; Teixidó, Neus; Larrigaudière, Christian; Giné-Bordonaba, Jordi

    2017-11-01

    The role of ethylene on inducing plant resistance or susceptibility to certain fungal pathogens clearly depends on the plant pathogen interaction with little or no-information available focused on the apple-Penicillium interaction. Taken advantage that Penicillium expansum is the compatible pathogen and P. digitatum is the non-host of apples, the present study aimed at deciphering how each Penicillium spp. could interfere in the fruit ethylene biosynthesis at the biochemical and molecular level. The infection capacity and different aspects related to the ethylene biosynthesis were conducted at different times post-inoculation. The results show that the fruit ethylene biosynthesis was differently altered during the P. expansum infection than in response to other biotic (non-host pathogen P. digitatum) or abiotic stresses (wounding). The first symptoms of the disease due to P. expansum were visible before the initiation of the fruit ethylene climacteric burst. Indeed, the ethylene climacteric burst was reduced in response to P. expansum concomitant to an important induction of MdACO3 gene expression and an inhibition (ca. 3-fold) and overexpression (ca. 2-fold) of ACO (1-Aminocyclopropane-1-carboxylic acid oxidase) and ACS (1-Aminocyclopropane-1-carboxylic acid synthase) enzyme activities, indicating a putative role of MdACO3 in the P. expansum-apple interaction which may, in turn, be related to System-1 ethylene biosynthesis. System-1 is auto-inhibited by ethylene and is characteristic of non-climateric or pre-climacteric fruit. Accordingly, we hypothesise that P. expansum may 'manipulate' the endogenous ethylene biosynthesis in apples, leading to the circumvention or suppression of effective defences hence facilitating its colonization. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  20. Fungal-host diversity among mycoheterotrophic plants increases proportionally to their fungal-host overlap.

    Science.gov (United States)

    Gomes, Sofia I F; Merckx, Vincent S F T; Saavedra, Serguei

    2017-05-01

    The vast majority of plants obtain an important proportion of vital resources from soil through mycorrhizal fungi. Generally, this happens in exchange of photosynthetically fixed carbon, but occasionally the interaction is mycoheterotrophic, and plants obtain carbon from mycorrhizal fungi. This process results in an antagonistic interaction between mycoheterotrophic plants and their fungal hosts. Importantly, the fungal-host diversity available for plants is restricted as mycoheterotrophic interactions often involve narrow lineages of fungal hosts. Unfortunately, little is known whether fungal-host diversity may be additionally modulated by plant-plant interactions through shared hosts. Yet, this may have important implications for plant competition and coexistence. Here, we use DNA sequencing data to investigate the interaction patterns between mycoheterotrophic plants and arbuscular mycorrhizal fungi. We find no phylogenetic signal on the number of fungal hosts nor on the fungal hosts shared among mycoheterotrophic plants. However, we observe a potential trend toward increased phylogenetic diversity of fungal hosts among mycoheterotrophic plants with increasing overlap in their fungal hosts. While these patterns remain for groups of plants regardless of location, we do find higher levels of overlap and diversity among plants from the same location. These findings suggest that species coexistence cannot be fully understood without attention to the two sides of ecological interactions.

  1. Protection by fungal starters against growth and secondary metabolite production of fungal spoilers of cheese.

    Science.gov (United States)

    Nielsen, M S; Frisvad, J C; Nielsen, P V

    1998-06-30

    The influence of fungal starter cultures on growth and secondary metabolite production of fungal contaminants associated with cheese was studied on laboratory media and Camembert cheese. Isolates of the species Penicillium nalgiovense, P. camemberti, P. roqueforti and Geotrichum candidum were used as fungal starters. The species P. commune, P. caseifulvum, P. verrucosum, P. discolor, P. solitum, P. coprophilum and Aspergillus versicolor were selected as contaminants. The fungal starters showed different competitive ability on laboratory media and Camembert cheese. The presence of the Penicillium species, especially P. nalgiovense, showed an inhibitory effect on the growth of the fungal contaminants on laboratory media. G. candidum caused a significant inhibition of the fungal contaminants on Camembert cheese. The results indicate that G. candidum plays an important role in competition with undesirable microorganisms in mould fermented cheeses. Among the starters, P. nalgiovense caused the largest reduction in secondary metabolite production of the fungal contaminants on the laboratory medium. On Camembert cheese no significant changes in metabolite production of the fungal contaminants was observed in the presence of the starters.

  2. Burden of serious fungal infections in Guatemala.

    Science.gov (United States)

    Medina, N; Samayoa, B; Lau-Bonilla, D; Denning, D W; Herrera, R; Mercado, D; Guzmán, B; Pérez, J C; Arathoon, E

    2017-06-01

    Guatemala is a developing country in Central America with a high burden of HIV and endemic fungal infections; we attempted to estimate the burden of serious fungal infections for the country. A full literature search was done to identify epidemiology papers reporting fungal infections from Guatemala. We used specific populations at risk and fungal infection frequencies in the population to estimate national rates. The population of Guatemala in 2013 was 15.4 million; 40% were younger than 15 and 6.2% older than 60. There are an estimated 53,000 adults with HIV infection, in 2015, most presenting late. The estimated cases of opportunistic fungal infections were: 705 cases of disseminated histoplasmosis, 408 cases of cryptococcal meningitis, 816 cases of Pneumocystis pneumonia, 16,695 cases of oral candidiasis, and 4,505 cases of esophageal candidiasis. In the general population, an estimated 5,568 adult asthmatics have allergic bronchopulmonary aspergillosis (ABPA) based on a 2.42% prevalence of asthma and a 2.5% ABPA proportion. Amongst 2,452 pulmonary tuberculosis patients, we estimated a prevalence of 495 for chronic pulmonary aspergillosis in this group, and 1,484 for all conditions. An estimated 232,357 cases of recurrent vulvovaginal candidiasis is likely. Overall, 1.7% of the population are affected by these conditions. The true fungal infection burden in Guatemala is unknown. Tools and training for improved diagnosis are needed. Additional research on prevalence is needed to employ public health measures towards treatment and improving the reported data of fungal diseases.

  3. Metazoan Remaining Genes for Essential Amino Acid Biosynthesis: Sequence Conservation and Evolutionary Analyses

    Directory of Open Access Journals (Sweden)

    Igor R. Costa

    2014-12-01

    Full Text Available Essential amino acids (EAA consist of a group of nine amino acids that animals are unable to synthesize via de novo pathways. Recently, it has been found that most metazoans lack the same set of enzymes responsible for the de novo EAA biosynthesis. Here we investigate the sequence conservation and evolution of all the metazoan remaining genes for EAA pathways. Initially, the set of all 49 enzymes responsible for the EAA de novo biosynthesis in yeast was retrieved. These enzymes were used as BLAST queries to search for similar sequences in a database containing 10 complete metazoan genomes. Eight enzymes typically attributed to EAA pathways were found to be ubiquitous in metazoan genomes, suggesting a conserved functional role. In this study, we address the question of how these genes evolved after losing their pathway partners. To do this, we compared metazoan genes with their fungal and plant orthologs. Using phylogenetic analysis with maximum likelihood, we found that acetolactate synthase (ALS and betaine-homocysteine S-methyltransferase (BHMT diverged from the expected Tree of Life (ToL relationships. High sequence conservation in the paraphyletic group Plant-Fungi was identified for these two genes using a newly developed Python algorithm. Selective pressure analysis of ALS and BHMT protein sequences showed higher non-synonymous mutation ratios in comparisons between metazoans/fungi and metazoans/plants, supporting the hypothesis that these two genes have undergone non-ToL evolution in animals.

  4. Full establishment of arbuscular mycorrhizal symbiosis in rice occurs independently of enzymatic jasmonate biosynthesis.

    Directory of Open Access Journals (Sweden)

    Caroline Gutjahr

    Full Text Available Development of the mutualistic arbuscular mycorrhiza (AM symbiosis between most land plants and fungi of the Glomeromycota is regulated by phytohormones. The role of jasmonate (JA in AM colonization has been investigated in the dicotyledons Medicago truncatula, tomato and Nicotiana attenuata and contradicting results have been obtained with respect to a neutral, promotive or inhibitory effect of JA on AM colonization. Furthermore, it is currently unknown whether JA plays a role in AM colonization of monocotyledonous roots. Therefore we examined whether JA biosynthesis is required for AM colonization of the monocot rice. To this end we employed the rice mutant constitutive photomorphogenesis 2 (cpm2, which is deficient in JA biosynthesis. Through a time course experiment the amount and morphology of fungal colonization did not differ between wild-type and cpm2 roots. Furthermore, no significant difference in the expression of AM marker genes was detected between wild type and cpm2. However, treatment of wild-type roots with 50 μM JA lead to a decrease of AM colonization and this was correlated with induction of the defense gene PR4. These results indicate that JA is not required for AM colonization of rice but high levels of JA in the roots suppress AM development likely through the induction of defense.

  5. Fungal Genomics for Energy and Environment

    Energy Technology Data Exchange (ETDEWEB)

    Grigoriev, Igor V.

    2013-03-11

    Genomes of fungi relevant to energy and environment are in focus of the Fungal Genomic Program at the US Department of Energy Joint Genome Institute (JGI). One of its projects, the Genomics Encyclopedia of Fungi, targets fungi related to plant health (symbionts, pathogens, and biocontrol agents) and biorefinery processes (cellulose degradation, sugar fermentation, industrial hosts) by means of genome sequencing and analysis. New chapters of the Encyclopedia can be opened with user proposals to the JGI Community Sequencing Program (CSP). Another JGI project, the 1000 fungal genomes, explores fungal diversity on genome level at scale and is open for users to nominate new species for sequencing. Over 200 fungal genomes have been sequenced by JGI to date and released through MycoCosm (www.jgi.doe.gov/fungi), a fungal web-portal, which integrates sequence and functional data with genome analysis tools for user community. Sequence analysis supported by functional genomics leads to developing parts list for complex systems ranging from ecosystems of biofuel crops to biorefineries. Recent examples of such parts suggested by comparative genomics and functional analysis in these areas are presented here.

  6. Fungal endophytes: modifiers of plant disease.

    Science.gov (United States)

    Busby, Posy E; Ridout, Mary; Newcombe, George

    2016-04-01

    Many recent studies have demonstrated that non-pathogenic fungi within plant microbiomes, i.e., endophytes ("endo" = within, "phyte" = plant), can significantly modify the expression of host plant disease. The rapid pace of advancement in endophyte ecology warrants a pause to synthesize our understanding of endophyte disease modification and to discuss future research directions. We reviewed recent literature on fungal endophyte disease modification, and here report on several emergent themes: (1) Fungal endophyte effects on plant disease span the full spectrum from pathogen antagonism to pathogen facilitation, with pathogen antagonism most commonly reported. (2) Agricultural plant pathosystems are the focus of research on endophyte disease modification. (3) A taxonomically diverse group of fungal endophytes can influence plant disease severity. And (4) Fungal endophyte effects on plant disease severity are context-dependent. Our review highlights the importance of fungal endophytes for plant disease across a broad range of plant pathosystems, yet simultaneously reveals that complexity within plant microbiomes presents a significant challenge to disentangling the biotic environmental factors affecting plant disease severity. Manipulative studies integrating eco-evolutionary approaches with emerging molecular tools will be poised to elucidate the functional importance of endophytes in natural plant pathosystems that are fundamental to biodiversity and conservation.

  7. Phylogenetic analysis of fungal ABC transporters.

    Science.gov (United States)

    Kovalchuk, Andriy; Driessen, Arnold J M

    2010-03-16

    The superfamily of ABC proteins is among the largest known in nature. Its members are mainly, but not exclusively, involved in the transport of a broad range of substrates across biological membranes. Many contribute to multidrug resistance in microbial pathogens and cancer cells. The diversity of ABC proteins in fungi is comparable with those in multicellular animals, but so far fungal ABC proteins have barely been studied. We performed a phylogenetic analysis of the ABC proteins extracted from the genomes of 27 fungal species from 18 orders representing 5 fungal phyla thereby covering the most important groups. Our analysis demonstrated that some of the subfamilies of ABC proteins remained highly conserved in fungi, while others have undergone a remarkable group-specific diversification. Members of the various fungal phyla also differed significantly in the number of ABC proteins found in their genomes, which is especially reduced in the yeast S. cerevisiae and S. pombe. Data obtained during our analysis should contribute to a better understanding of the diversity of the fungal ABC proteins and provide important clues about their possible biological functions.

  8. Fungal endophytes for sustainable crop production.

    Science.gov (United States)

    Lugtenberg, Ben J J; Caradus, John R; Johnson, Linda J

    2016-12-01

    This minireview highlights the importance of endophytic fungi for sustainable agriculture and horticulture production. Fungal endophytes play a key role in habitat adaptation of plants resulting in improved plant performance and plant protection against biotic and abiotic stresses. They encode a vast variety of novel secondary metabolites including volatile organic compounds. In addition to protecting plants against pathogens and pests, selected fungal endophytes have been used to remove animal toxicities associated with fungal endophytes in temperate grasses, to create corn and rice plants that are tolerant to a range of biotic and abiotic stresses, and for improved management of post-harvest control. We argue that practices used in plant breeding, seed treatments and agriculture, often caused by poor knowledge of the importance of fungal endophytes, are among the reasons for the loss of fungal endophyte diversity in domesticated plants and also accounts for the reduced effectiveness of some endophyte strains to confer plant benefits. We provide recommendations on how to mitigate against these negative impacts in modern agriculture. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Fueling the Future with Fungal Genomes

    Energy Technology Data Exchange (ETDEWEB)

    Grigoriev, Igor V.

    2014-10-27

    Genomes of fungi relevant to energy and environment are in focus of the JGI Fungal Genomic Program. One of its projects, the Genomics Encyclopedia of Fungi, targets fungi related to plant health (symbionts and pathogens) and biorefinery processes (cellulose degradation and sugar fermentation) by means of genome sequencing and analysis. New chapters of the Encyclopedia can be opened with user proposals to the JGI Community Science Program (CSP). Another JGI project, the 1000 fungal genomes, explores fungal diversity on genome level at scale and is open for users to nominate new species for sequencing. Over 400 fungal genomes have been sequenced by JGI to date and released through MycoCosm (www.jgi.doe.gov/fungi), a fungal web-portal, which integrates sequence and functional data with genome analysis tools for user community. Sequence analysis supported by functional genomics will lead to developing parts list for complex systems ranging from ecosystems of biofuel crops to biorefineries. Recent examples of such ‘parts’ suggested by comparative genomics and functional analysis in these areas are presented here.

  10. Linker Flexibility Facilitates Module Exchange in Fungal Hybrid PKS-NRPS Engineering

    DEFF Research Database (Denmark)

    Nielsen, Maria Lund; Petersen, Thomas Isbrandt; Petersen, Lene Maj

    2016-01-01

    Polyketide synthases (PKSs) and nonribosomal peptide synthetases (NRPSs) each give rise to a vast array of complex bioactive molecules with further complexity added by the existence of natural PKS-NRPS fusions. Rational genetic engineering for the production of natural product derivatives....... We succeeded in the construction of a functional cross-species chimeric PKS-NRPS expressed in Aspergillus nidulans. Module swapping of the two PKS-NRPS natural hybrids CcsA from Aspergillus clavatus involved in the biosynthesis of cytochalasin E and related Syn2 from rice plant pathogen Magnaporthe...... oryzae lead to production of novel hybrid products, demonstrating that the rational re-design of these fungal natural product enzymes is feasible. We also report the structure of four novel pseudo pre-cytochalasin intermediates, niduclavin and niduporthin along with the chimeric compounds niduchimaeralin...

  11. Circadian rhythm of anti-fungal prenylated chromene in leaves of Piper aduncum.

    Science.gov (United States)

    Morandim, Andreia de A; Bergamo, Débora Cristina B; Kato, Massuo Jorge; Cavalheiro, Alberto José; Bolzani, Vanderlan da S; Furlan, Maysa

    2005-01-01

    Leaves of Piper aduncum accumulate the anti-fungal chromenes methyl 2,2-dimethyl-2H-1-chromene-6-carboxylate (1) and methyl 2,2-dimethyl-8-(3'-methyl-2'-butenyl)-2H-1-chromene-6-carboxylate (2). The enzymatic formation of 2 from dimethylallyl diphosphate and 1 was investigated using cell-free extracts of the title plant. An HPLC assay for the prenylation reaction was developed and the enzyme activity measured in the protein extracts. The prenyltransferase that catalyses the transfer of the dimethylallyl group to C-2' of 1 was soluble and required dimethylallyl diphosphate as the prenyl donor. In the leaves, the biosynthesis of the prenylated chromene 2 was time-regulated and prenyltransferase activity depended upon circadian variation. Preliminary characterisation and purification experiments on the prenyltransferase from P. aduncum have been performed.

  12. Ecological screening of lipolytic cultures and process optimization for extracellular lipase production from fungal hyperproducer

    International Nuclear Information System (INIS)

    Iftikhar, T.; Niaz, M.; Anwer, M.; Abbas, S.Q.; Saleem, M.; Jabeen, R.

    2011-01-01

    Present investigation describes the biosynthesis of extracellular lipases by various local fungal strains isolated from various lipid rich habitats of Faisalabad. The isolated cultures of Aspergillus niger, Penicillium chrysogenum, Rhizopus microsporus, Mucor mucedo, Alternaria alternata, Trichophyton sp., Fusarium semitectum, E (un-identified), Curvularia sp., Aspergillus flavus, G (un-identified), F (Mucor sp.) and H (Synnematous) were identified and screened for the extracelluler lipases production. Different environmental parameters such as pH, temperature, inoculum size, amount of substrate and incubation time were optimized for the selected hyper producer. It was found that maximum production of lipases by Trichophyton sp., was obtained after 48 h of batch fermentation. Similarly, the diluent pH of 7.0 and incubation temperature of 30 deg. C were found optimum for enzyme production by the microorganism. The maximum production of lipases during the course of present studies was 65.20 +- 1.13a U/g. (author)

  13. Optimization of silver nanoparticles biosynthesis mediated by Aspergillus niger NRC1731 through application of statistical methods: enhancement and characterization.

    Science.gov (United States)

    Elsayed, Maysa A; Othman, Abdelmageed M; Hassan, Mohamed M; Elshafei, Ali M

    2018-03-01

    The fungal-mediated silver nanoparticles (AgNPs) biosynthesis optimization via the application of central composite design (CCD) response surface to develop an effective ecofriendly and inexpensive green process was the aim of the current study. Nanosilver biosynthesis using the Aspergillus niger NRC1731 cell-free filtrate (CFF) was studied through involving the most parameters affecting the AgNPs green synthesis and its interactions effects. The statistical optimization models showed that using 59.37% of CFF in reaction containing 1.82 mM silver nitrate for 34 h at pH 7.0 is the optimum value to optimize the AgNPs biosynthesis. The obtained AgNPs were characterized by means of electron microscopy, UV/visible spectrophotometry, energy dispersive X-ray analysis and infrared spectroscopy to elucidate its almost spherical shape with diameter of 3-20 nm. The produced AgNPs exhibited a considerable antimicrobial activity against Bacillus mycoides , Escherichia coli in addition to Candida albicans .

  14. Structural basis for phosphatidylinositol-phosphate biosynthesis

    Science.gov (United States)

    Clarke, Oliver B.; Tomasek, David; Jorge, Carla D.; Dufrisne, Meagan Belcher; Kim, Minah; Banerjee, Surajit; Rajashankar, Kanagalaghatta R.; Shapiro, Lawrence; Hendrickson, Wayne A.; Santos, Helena; Mancia, Filippo

    2015-10-01

    Phosphatidylinositol is critical for intracellular signalling and anchoring of carbohydrates and proteins to outer cellular membranes. The defining step in phosphatidylinositol biosynthesis is catalysed by CDP-alcohol phosphotransferases, transmembrane enzymes that use CDP-diacylglycerol as donor substrate for this reaction, and either inositol in eukaryotes or inositol phosphate in prokaryotes as the acceptor alcohol. Here we report the structures of a related enzyme, the phosphatidylinositol-phosphate synthase from Renibacterium salmoninarum, with and without bound CDP-diacylglycerol to 3.6 and 2.5 Å resolution, respectively. These structures reveal the location of the acceptor site, and the molecular determinants of substrate specificity and catalysis. Functional characterization of the 40%-identical ortholog from Mycobacterium tuberculosis, a potential target for the development of novel anti-tuberculosis drugs, supports the proposed mechanism of substrate binding and catalysis. This work therefore provides a structural and functional framework to understand the mechanism of phosphatidylinositol-phosphate biosynthesis.

  15. Occurrence and biosynthesis of carotenoids in phytoplankton.

    Science.gov (United States)

    Huang, Jim Junhui; Lin, Shaoling; Xu, Wenwen; Cheung, Peter Chi Keung

    2017-09-01

    Naturally occurring carotenoids are important sources of antioxidants, anti-cancer compounds and anti-inflammatory agents and there is thus considerable market demand for their pharmaceutical applications. Carotenoids are widely distributed in marine and freshwater organisms including microalgae, phytoplankton, crustaceans and fish, as well as in terrestrial plants and birds. Recently, phytoplankton-derived carotenoids have received much attention due to their abundance, rapid rate of biosynthesis and unique composition. The carotenoids that accumulate in particular phytoplankton phyla are synthesized by specific enzymes and play unique physiological roles. This review focuses on studies related to the occurrence of carotenoids in different phytoplankton phyla and the molecular aspects of their biosynthesis. Recent biotechnological advances in the isolation and characterization of some representative carotenoid synthases in phytoplankton are also discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Molecular Diagnostics for Soilborne Fungal Pathogens

    Directory of Open Access Journals (Sweden)

    E.J. Paplomatas

    2004-08-01

    Full Text Available Several classical approaches have been developed to detect and identify soil fungal inhabitants through the years. Selective media have been devised to exclude the large number of soil organisms and allow growth of target fungi. However the advent of molecular biology has offered a number of revolutionary insights into the detection and enumeration of soilborne fungal pathogens and also has started to provide information on the identification of unknown species from DNA sequences. This review paper focuses on the application of various molecular techniques in the detection, identification, characterization and quantification of soilborne fungal plant pathogens. This is based on information from the literature and is combined with personal research findings of the author.

  17. Fungal endophytes of sorghum in Burkina Faso

    DEFF Research Database (Denmark)

    Zida, E P; Thio, I G; Néya, B J

    2014-01-01

    A survey was conducted to assess the natural occurrence and distribution of fungal endophytes in sorghum in relation to plant performance in two distinct agro-ecological zones in Burkina Faso. Sorghum farm-saved seeds were sown in 48 farmers’ fields in Sahelian and North Sudanian zones to produce...... sorghum plants. In each field, leaf samples were collected from five well-developed (performing) and five less-developed (non-performing) plants at 3-5 leaf stage, while at plant maturity leaf, stem and root samples were collected from the same plants and fungal endophytes were isolated. A total of 39...... fungal species belonging to 25 genera were isolated. The most represented genera included Fusarium, Leptosphaeria, Curvularia, Nigrospora and Penicillium. The genera Fusarium and Penicillium occurred significantly higher in performing plants as compared to non-performing plants while the genera...

  18. Investigation of toxigenic potential of fungal species by the use of simple screening method

    Directory of Open Access Journals (Sweden)

    Bočarov-Stančić Aleksandra S.

    2009-01-01

    Full Text Available Potential for the biosynthesis of aflatoxin B1 (AFLB1, ochratoxin A (OTA, diacetoxyscirpenol (DAS, T-2 toxin (T2, and zearalenone (ZON was investigated in different fungal species belonging to the genera: Aspergillus, Fusarium and Penicillium. The majority of investigated isolates originated from cereal grains, crushed oil soybean seed and fodder mixtures. The simple screening method developed by Filtenborg et al. (1983 was applied with few modifications concerning the type of the medium and cultivation temperature. In order to optimise the biosynthetic conditions for different mycotoxins, the following control cultures, known as mycotin producers were used: OTA - A. ochraceus CBS 108.08, DAS - F. semitectum (SL-B i SL-C, T2 - F. sporotrichioides (ITM-391, M-1-1, R-2301 and ZON - F. graminearum (GZ-LES. The fungi were cultivated on the standard medium (YESA - 2% yeast extract, 15% sucrose and 2% agar, pH 6.5, three modifications of the basic medium (YESAZn - the standard medium supplemented with 0.23 mg/l ZnSO4 x 5 H2O; PPSA - the medium in which yeast extract was replaced with peptone-1; PPSAZn - the medium in which yeast extract was replaced with peptone-1 and supplemented with 0.23 mg/l ZnSO4 x 5 H2O, and the potato-dextrose agar (PDA. The earlier biosynthesis of tested mycotoxins was recorded under the following cultivation conditions of fungal species: AFLB1 - after 14 days on PDA at 27±1°C, OTA - after 10 days on YESA and YESAZn at 27±1°C, DAS - after 10 days on PPSA and PPSAZn at 27±1°C, T2 - after 7 days on PPSAZn and PPSA at room temperature (20-24°C, and ZON - after 1 week on YESA and YESAZn at room temperature (21-24°C.

  19. Identification & Characterization of Fungal Ice Nucleation Proteins

    Science.gov (United States)

    Scheel, Jan Frederik; Kunert, Anna Theresa; Kampf, Christopher Johannes; Mauri, Sergio; Weidner, Tobias; Pöschl, Ulrich; Fröhlich-Nowoisky, Janine

    2016-04-01

    Freezing of water at relatively warm subfreezing temperatures is dependent on ice nucleation catalysis facilitated by ice nuclei (IN). These IN can be of various origins and although extensive research was done and progress was achieved, the nature and mechanisms leading to an effective IN are to date still poorly understood. Some of the most important processes of our geosphere like the water cycle are highly dependent on effective ice nucleation at temperatures between -2°C - -8°C, a temperature range which is almost exclusively covered by biological IN (BioIN). BioIN are usually macromolecular structures of biological polymers. Sugars as well as proteins have been reported to serve as IN and the best characterized BioIN are ice nucleation proteins (IN-P) from gram negative bacteria. Fungal strains from Fusarium spp. were described to be effective IN at subfreezing temperatures up to -2°C already 25 years ago and more and more fungal species are described to serve as efficient IN. Fungal IN are also thought to be proteins or at least contain a proteinaceous compound, but to date the fungal IN-P primary structure as well as their coding genetic elements of all IN active fungi are unknown. The aim of this study is a.) to identify the proteins and their coding genetic elements from IN active fungi (F. acuminatum, F. avenaceum, M. alpina) and b.) to characterize the mechanisms by which fungal IN serve as effective IN. We designed an interdisciplinary approach using biological, analytical and physical methods to identify fungal IN-P and describe their biological, chemical, and physical properties.

  20. Mucormycosis: a devastating fungal infection in diabetics

    International Nuclear Information System (INIS)

    Rashid, M.; Bari, A.; Mehmood, S.; Tariq, K.M.; Haq, I.; Niwaz, Z.

    2005-01-01

    Mucormycosis is a highly invasive, devastating and usually fatal fungal infection of the sinuses, brain, or lungs that occurs primarily in people with immune disorders. Despite advances in diagnosis and treatment, a high mortality still exists. We present a middle aged diabetic male with this serious fungal infection involving nose, paranasal area and adjacent periorbital regions with a high risk of progressing further towards the dura mater. He was promptly diagnosed and managed with serial surgical debridements with systemic antifungals and was later fitted with a nasal prosthesis. (author)

  1. Fungal infections of the lung in children

    Energy Technology Data Exchange (ETDEWEB)

    Toma, Paolo; Colafati, Giovanna Stefania; D' Andrea, Maria Luisa [IRCCS Bambino Gesu Children' s Hospital, Department of Imaging, Rome (Italy); Bertaina, Alice; Mastronuzzi, Angela [IRCCS Bambino Gesu Children' s Hospital, Department of Pediatric Hematology/Oncology and Transfusion Medicine, Rome (Italy); Castagnola, Elio [IRCCS Istituto Giannina Gaslini, Department of Infective Diseases, Genoa (Italy); Finocchi, Andrea [IRCCS Bambino Gesu Children' s Hospital, Department of Pediatrics, Rome (Italy); Lucidi, Vincenzina [IRCCS Bambino Gesu Children' s Hospital, Cystic Fibrosis Center, Rome (Italy); Granata, Claudio [IRCCS Istituto Giannina Gaslini, Department of Pediatric Radiology, Genoa (Italy)

    2016-12-15

    Fungal infections of the lungs are relatively common and potentially life-threatening conditions in immunocompromised children. The role of imaging in children with lung mycosis is to delineate the extension of pulmonary involvement, to assess response to therapy, and to monitor for adverse sequelae such as bronchiectasis and cavitation. The aim of this paper is to show imaging findings in a series of patients with fungal pneumonia from two tertiary children's hospitals, to discuss differential diagnoses and to show how imaging findings can vary depending on the host immune response. (orig.)

  2. MycoCosm, an Integrated Fungal Genomics Resource

    Energy Technology Data Exchange (ETDEWEB)

    Shabalov, Igor; Grigoriev, Igor

    2012-03-16

    MycoCosm is a web-based interactive fungal genomics resource, which was first released in March 2010, in response to an urgent call from the fungal community for integration of all fungal genomes and analytical tools in one place (Pan-fungal data resources meeting, Feb 21-22, 2010, Alexandria, VA). MycoCosm integrates genomics data and analysis tools to navigate through over 100 fungal genomes sequenced at JGI and elsewhere. This resource allows users to explore fungal genomes in the context of both genome-centric analysis and comparative genomics, and promotes user community participation in data submission, annotation and analysis. MycoCosm has over 4500 unique visitors/month or 35000+ visitors/year as well as hundreds of registered users contributing their data and expertise to this resource. Its scalable architecture allows significant expansion of the data expected from JGI Fungal Genomics Program, its users, and integration with external resources used by fungal community.

  3. De novo transcriptome analyses of host-fungal interactions in oil palm (Elaeis guineensis Jacq.).

    Science.gov (United States)

    Ho, Chai-Ling; Tan, Yung-Chie; Yeoh, Keat-Ai; Ghazali, Ahmad-Kamal; Yee, Wai-Yan; Hoh, Chee-Choong

    2016-01-19

    Basal stem rot (BSR) is a fungal disease in oil palm (Elaeis guineensis Jacq.) which is caused by hemibiotrophic white rot fungi belonging to the Ganoderma genus. Molecular responses of oil palm to these pathogens are not well known although this information is crucial to strategize effective measures to eradicate BSR. In order to elucidate the molecular interactions between oil palm and G. boninense and its biocontrol fungus Trichoderma harzianum, we compared the root transcriptomes of untreated oil palm seedlings with those inoculated with G. boninense and T. harzianum, respectively. Differential gene expression analyses revealed that jasmonate (JA) and salicylate (SA) may act in an antagonistic manner in affecting the hormone biosynthesis, signaling, and downstream defense responses in G. boninense-treated oil palm roots. In addition, G. boninense may compete with the host to control disease symptom through the transcriptional regulation of ethylene (ET) biosynthesis, reactive oxygen species (ROS) production and scavenging. The strengthening of host cell walls and production of pathogenesis-related proteins as well as antifungal secondary metabolites in host plants, are among the important defense mechanisms deployed by oil palm against G. boninense. Meanwhile, endophytic T. harzianum was shown to improve the of nutrition status and nutrient transportation in host plants. The findings of this analysis have enhanced our understanding on the molecular interactions of G. boninense and oil palm, and also the biocontrol mechanisms involving T. harzianum, thus contributing to future formulations of better strategies for prevention and treatment of BSR.

  4. FvSet2 regulates fungal growth, pathogenicity, and secondary metabolism in Fusarium verticillioides.

    Science.gov (United States)

    Gu, Qin; Wang, Zhenzhong; Sun, Xiao; Ji, Tiantian; Huang, Hai; Yang, Yang; Zhang, Hao; Tahir, Hafiz Abdul Samad; Wu, Liming; Wu, Huijun; Gao, Xuewen

    2017-10-01

    Histone H3 lysine 36 methylation (H3K36me) is generally associated with activation of gene expression in most eukaryotic cells. However, the function of H3K36me in filamentous fungi is largely unknown. Set2 is the sole lysine histone methyltransferase (KHMTase) enzyme responsible for the methylation of H3K36 in Saccharomyces cerevisiae. In the current study, we identified a single ortholog of S. cerevisiae Set2 in Fusarium verticillioides. We report that FvSet2 is responsible for the trimethylation of H3K36 (H3K36me3). The FvSET2 deletion mutant (ΔFvSet2) showed significant defects in vegetative growth, FB 1 biosynthesis, pigmentation, and fungal virulence. Furthermore, trimethylation of H3K36 was found to be important for active transcription of genes involved in FB 1 and bikaverin biosyntheses. These data indicate that FvSet2 plays an important role in the regulation of secondary metabolism, vegetative growth and fungal virulence in F. verticillioides. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Packaging conditions hindering fungal growth on cheese

    DEFF Research Database (Denmark)

    Nielsen, Per Væggemose; Haasum, Iben

    1997-01-01

    Fungal contamination is one of the most important quality deteriorating factors on cheese. During the last 5 years we have studied in detail the underlying factors controlling these unwanted processes in a collaborative project financed by the Danish Dairy Board and the Ministry of Agriculture...

  6. Fungal peroxidases : molecular aspects and applications

    NARCIS (Netherlands)

    Conesa, A.; Punt, P.J.; Hondel, C.A.M.J.J.

    2002-01-01

    Peroxidases are oxidoreductases that utilize hydrogen peroxide to catalyze oxidative reactions. A large number of peroxidases have been identified in fungal species and are being characterized at the molecular level. In this manuscript we review the current knowledge on the molecular aspects of this

  7. Fungal Planet description sheets: 400-468

    Czech Academy of Sciences Publication Activity Database

    Crous, P.W.; Wingfield, M. J.; Richardson, D. M.; Le Roux, J. J.; Strasberg, D.; Edwards, J.; Roets, F.; Hubka, V.; Taylor, P.W.J.; Heykoop, M.; Martín, M.P.; Moreno, G.; Sutton, D.A.; Wiederhold, N.P.; Barnes, C.W.; Carlavilla, J.R.; Gené, J.; Giraldo, A.; Guarnaccia, V.; Guarro, J.; Hernández-Restrepo, M.; Kolařík, Miroslav; Manjón, J.L.; Pascoe, I.G.; Popov, E.S.; Sandoval-Denis, M.; Woudenberg, J.H.C.; Acharya, K.; Alexandrova, A.V.; Alvarado, P.; Barbosa, R.N.; Baseia, I.G.; Blanchette, R.A.; Boekhout, T.; Burgess, T.I.; Cano-Lira, J.F.; Čmoková, A.; Dimitrov, R.A.; Dyakov, M.Yu.; Dueñas, M.; Dutta, A.K.; Esteve- Raventós, F.; Fedosova, A.G.; Fournier, J.; Gamboa, P.; Gouliamova, D.E.; Grebenc, T.; Groenewald, M.; Hanse, B.; Hardy, G.E.St.J.; Held, B.W.; Jurjević, Ž.; Kaewgrajang, T.; Latha, K.P.D.; Lombard, L.; Luangsa-Ard, J.J.; Lysková, P.; Mallátová, N.; Manimohan, P.; Miller, A.N.; Mirabolfathy, M.; Morozova, O.V.; Obodai, M.; Oliveira, N.T.; Otto, E.C.; Paloi, S.; Peterson, S.W.; Phosri, C.; Roux, J.; Salazar, W.A.; Sánchez, A.; Sarria, G.A.; Shin, H.-D.; Silva, B.D.B.; Silva, G.A.; Smith, M.Th.; Souza-Motta, C.M.; Stchigel, A.M.; Stoilova-Disheva, M.M.; Sulzbacher, M.A.; Telleria, M.T.; Toapanta, C.; Traba, J.M.; Valenzuela-Lopez, N.; Watling, R.; Groenewald, J.Z.

    2016-01-01

    Roč. 36, July (2016), s. 316-458 ISSN 0031-5850 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61388971 Keywords : ITS DNA barcodes * LSU * fungal species Subject RIV: EE - Microbiology, Virology Impact factor: 7.511, year: 2016

  8. A biotechnology perspective of fungal proteases

    Directory of Open Access Journals (Sweden)

    Paula Monteiro de Souza

    2015-06-01

    Full Text Available Proteases hydrolyze the peptide bonds of proteins into peptides and amino acids, being found in all living organisms, and are essential for cell growth and differentiation. Proteolytic enzymes have potential application in a wide number of industrial processes such as food, laundry detergent and pharmaceutical. Proteases from microbial sources have dominated applications in industrial sectors. Fungal proteases are used for hydrolyzing protein and other components of soy beans and wheat in soy sauce production. Proteases can be produced in large quantities in a short time by established methods of fermentation. The parameters such as variation in C/N ratio, presence of some sugars, besides several other physical factors are important in the development of fermentation process. Proteases of fungal origin can be produced cost effectively, have an advantage faster production, the ease with which the enzymes can be modified and mycelium can be easily removed by filtration. The production of proteases has been carried out using submerged fermentation, but conditions in solid state fermentation lead to several potential advantages for the production of fungal enzymes. This review focuses on the production of fungal proteases, their distribution, structural-functional aspects, physical and chemical parameters, and the use of these enzymes in industrial applications.

  9. High prevalence of a fungal prion

    NARCIS (Netherlands)

    Debets, A.J.M.; Dalstra, H.J.P.; Slakhorst, S.M.; Koopmanschap-Memelink, A.B.; Hoekstra, R.F.; Saupe, S.J.

    2012-01-01

    Prions are infectious proteins that cause fatal diseases in mammals. Prions have also been found in fungi, but studies on their role in nature are scarce. The proposed biological function of fungal prions is debated and varies from detrimental to benign or even beneficial. [Het-s] is a prion of the

  10. October 2012 Multistate Fungal Meningitis Outbreak

    Centers for Disease Control (CDC) Podcasts

    2012-10-17

    This podcast gives an overview of the October 2012 multistate fungal meningitis outbreak, including symptoms to watch for and a website for up-to-date information.  Created: 10/17/2012 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 10/17/2012.

  11. Fungal biology and agriculture: revisiting the field

    Science.gov (United States)

    Yarden, O.; Ebbole, D.J.; Freeman, S.; Rodriguez, R.J.; Dickman, M. B.

    2003-01-01

    Plant pathology has made significant progress over the years, a process that involved overcoming a variety of conceptual and technological hurdles. Descriptive mycology and the advent of chemical plant-disease management have been followed by biochemical and physiological studies of fungi and their hosts. The later establishment of biochemical genetics along with the introduction of DNA-mediated transformation have set the stage for dissection of gene function and advances in our understanding of fungal cell biology and plant-fungus interactions. Currently, with the advent of high-throughput technologies, we have the capacity to acquire vast data sets that have direct relevance to the numerous subdisciplines within fungal biology and pathology. These data provide unique opportunities for basic research and for engineering solutions to important agricultural problems. However, we also are faced with the challenge of data organization and mining to analyze the relationships between fungal and plant genomes and to elucidate the physiological function of pertinent DNA sequences. We present our perspective of fungal biology and agriculture, including administrative and political challenges to plant protection research.

  12. Fungal Systematics and Evolution: FUSE 1

    NARCIS (Netherlands)

    Crous, Pedro W; Schumacher, René K; Wingfield, Michael J; Lombard, Lorenzo; Giraldo, Alejandra; Christensen, Martha; Gardiennet, Alain; Nakashima, Chiharu; Pereira, Olinto L; Smith, Alexander J; Groenewald, Johannes Z

    2015-01-01

    Fungal Systematics and Evolution (FUSE) is introduced as a new series to expedite the publication of issues relating to the epitypification of formerly described species, report new sexual-asexual connections, the merging of sexual and asexual gen¬era following the end of dual nomenclature, and to

  13. Fungal Planet description sheets: 371-399

    Czech Academy of Sciences Publication Activity Database

    Crous, P. W.; Wingfield, M. J.; Le Roux, J. J.; Richardson, D. M.; Strasberg, D.; Shivas, R.G.; Alvarado, P.; Edwards, J.; Moreno, G.; Sharma, R.; Sonawane, M.S.; Tan, Y.P.; Altés, A.; Barasubiye, T.; Barnes, C.W.; Blanchette, R.A.; Boertmann, D.; Bogo, A.; Carlavilla, J.R.; Cheewangkoon, R.; Daniel, R.; de Beer, Z.W.; de Yáňez-Morales, J.; Duong, T.A.; Fernández-Vicente, J.; Geering, A.D.W.; Guest, D.I.; Held, B.W.; Heykoop, M.; Hubka, V.; Ismail, A.M.; Kajale, S.C.; Khemmuk, W.; Kolařík, Miroslav; Kurli, R.; Lebeuf, R.; Levesque, C.A.; Lombard, L.; Magista, D.; Manjón, J.L.; Marincowitz, S.; Mohedano, J.M.; Nováková, Alena; Oberlies, N.H.; Otto, E.C.; Paguigan, N.D.; Pascoe, I.G.; Peréz-Butrón, J.L.; Perrone, G.; Rahi, P.; Raja, H.A.; Rintoul, T.; Sanhueza, R.M.V.; Scarlett, K.; Shouche, Y.S.; Shuttleworth, L.A.; Taylor, P.W.J.; Thorn, R.G.; Vawdrey, L.L.; Solano-Vidal, R.; Voitk, A.; Wong, P.T.W.; Wood, A.R.; Zamora, J.C.; Groenewald, J.Z.

    2015-01-01

    Roč. 35, December (2015), s. 264-327 ISSN 0031-5850 R&D Projects: GA ČR(CZ) GAP506/12/1064 Institutional support: RVO:61388971 Keywords : ITS DNA barcodes * LSU * novel fungal species Subject RIV: EE - Microbiology, Virology Impact factor: 5.725, year: 2015

  14. Fungal ABC Transporter Deletion and Localization Analysis

    NARCIS (Netherlands)

    Kovalchuk, A.; Weber, S.S.; Nijland, J.G.; Bovenberg, R.A.L.; Driessen, A.J.M.

    2012-01-01

    Fungal cells are highly complex as their metabolism is compartmentalized harboring various types of subcellular organelles that are bordered by one or more membranes. Knowledge about the intracellular localization of transporter proteins is often required for the understanding of their biological

  15. CT scan findings of fungal pneumonia

    International Nuclear Information System (INIS)

    Heckmann, M.; Uder, M.; Bautz, W.; Heinrich, M.

    2008-01-01

    The importance of fungal infection of the lung in immunocompromised patients has increased substantially during the last decades. Numerically the most patients are those with neutropenia, e.g. patients with malignancies or solid organ and stem cell transplantation, chemotherapy, corticosteroid use and HIV infection. Although fungal infections can occur in immunocompetent patients, their frequency in this population is rare. The clinical symptoms such as fever accompanied with non-productive cough are unspecific. In some patients progression to hypoxemia and dyspnea may occur rapidly. In spite of improved antifungal therapy morbidity and mortality of these infections are still high. Therefore an early and non-invasive diagnosis is very important. That is why CT and even better High-Resolution-CT (HR-CT) is a very important modality in examining immunocompromised patients with a probability of fungal infection. CT is everywhere available and, as a non-invasive method, able to give the relevant diagnose efficiently. This paper should give an overview about the radiologic findings and possible differential diagnosis of diverse pulmonary fungal infections in CT. Pneumonias caused by Aspergillus, Cryptococcus, Candida, Histoplasma, Mucor and Geotrichum capitatum are illustrated. (orig.)

  16. The Amstersam declaration on fungal nomenclature

    DEFF Research Database (Denmark)

    Hawksworth, David L.; Crous, Pedro W.; Redhead, Scott A.

    2011-01-01

    The Amsterdam Declaration on Fungal Nomenclature was agreed at an international symposium convened in Amsterdam on 19–20 April 2011 under the auspices of the International Commission on the Taxonomy of Fungi (ICTF). The purpose of the symposium was to address the issue of whether or how the current...

  17. 50-plus years of fungal viruses

    Energy Technology Data Exchange (ETDEWEB)

    Ghabrial, Said A., E-mail: saghab00@email.uky.edu [Plant Pathology Department, University of Kentucky, Lexington, KY (United States); Castón, José R. [Department of Structure of Macromolecules, Centro Nacional Biotecnologıa/CSIC, Campus de Cantoblanco, Madrid (Spain); Jiang, Daohong [State Key Lab of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei Province (China); Nibert, Max L. [Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA (United States); Suzuki, Nobuhiro [Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama (Japan)

    2015-05-15

    Mycoviruses are widespread in all major taxa of fungi. They are transmitted intracellularly during cell division, sporogenesis, and/or cell-to-cell fusion (hyphal anastomosis), and thus their life cycles generally lack an extracellular phase. Their natural host ranges are limited to individuals within the same or closely related vegetative compatibility groups, although recent advances have established expanded experimental host ranges for some mycoviruses. Most known mycoviruses have dsRNA genomes packaged in isometric particles, but an increasing number of positive- or negative-strand ssRNA and ssDNA viruses have been isolated and characterized. Although many mycoviruses do not have marked effects on their hosts, those that reduce the virulence of their phytopathogenic fungal hosts are of considerable interest for development of novel biocontrol strategies. Mycoviruses that infect endophytic fungi and those that encode killer toxins are also of special interest. Structural analyses of mycoviruses have promoted better understanding of virus assembly, function, and evolution. - Highlights: • Historical perspective of fungal virus research. • Description, classification and diversity of fungal virus families. • Structural features of fungal virus particles. • Hypovirulence and exploitation of mycoviruses in biological control of plant pathogenic fungi.

  18. Fungal peritonitis in children on peritoneal dialysis.

    NARCIS (Netherlands)

    Raaijmakers, R.; Schroder, C.; Monnens, L.A.H.; Cornelissen, E.A.M.; Warris, A.

    2007-01-01

    Fungal peritonitis is a rare but serious complication in children on peritoneal dialysis (PD). In this study, risk factors were evaluated, and therapeutic measures were reviewed. A retrospective, multi-centre study was performed in 159 Dutch paediatric PD patients, between 1980 and 2005 (3,573

  19. UV-guided isolation of fungal metabolites by HSCCC

    DEFF Research Database (Denmark)

    Dalsgaard, P.W.; Nielsen, K.F.; Larsen, Thomas Ostenfeld

    2005-01-01

    Analytical standardised reversed phase liquid chromatography (RPLC) data can be helpful in finding a suitable solvent combination for isolation of fungal metabolites by high-speed counter current chromatography. Analysis of the distribution coefficient (K-D) of fungal metabolites in a series...... peptides from a crude fungal extract....

  20. Induced effect of Ca2+ on dalesconols A and B biosynthesis in the culture of Daldinia eschscholzii via calcium/calmodulin signaling.

    Science.gov (United States)

    Lu, Yanhua; Pan, Zhenghua; Tao, Jun; An, Faliang

    2018-02-01

    Dalesconols (dalesconols A and B) were isolated from Daldinia eschscholzii and have remarkable immunosuppressive activity. In this study, the response of fungal growth, intra- and extracellular Ca 2+ , and dalesconols production after CaCl 2 addition were reported for the first time. After supplementation with 5 mM Ca 2+ at 24 h, dalesconols production reached 84.33 mg/L, which resulted in a 1.57-fold enhancement compared to the control. The key role of calcium/calmodulin signaling in dalesconols biosynthesis was confirmed by treatment with Ca 2+ channel and calmodulin inhibitors. The transcriptional levels of dalesconols biosynthetic genes were up-regulated after CaCl 2 addition and down-regulated after inhibitors were added. The results demonstrated that Ca 2+ addition induces dalesconols biosynthesis through up-regulation of dalesconols biosynthesis genes via regulation of calcium/calmodulin signaling. This study provided an efficient strategy for improving dalesconols production and would facilitate further research on the biosynthesis and regulation of dalesconols. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  1. Burden of Serious Fungal Infections in Jordan

    Directory of Open Access Journals (Sweden)

    Jamal Wadi

    2018-01-01

    Full Text Available Objective: To estimate the burden of fungal infections in Jordan for the first time. Material and Methods: Population data was from UN 2011 statistics and TB cases from WHO in 2012. Fewer than 100 patients with HIV were recorded in Jordan in 2013. Approximately 100 renal transplants and eight liver transplants are performed annually. There were 12,233 major surgical procedures in Jordan in 2013, of which 5.3% were major abdominal surgeries; candidemia was estimated in 5% of the population based on other countries, with 33% occurring in the ICU. Candida peritonitis/intra-abdominal candidiasis was estimated to affect 50% of the number of ICU candidemia cases. No adult asthma rates have been recorded for Jordan, so the rate from the Holy Land (8.54% clinical asthma from To et al. has been used. There are an estimated 49,607 chronic obstructive pulmonary disease (COPD patients in Jordan, with 64% symptomatic, 25% Gold stage 3% or 4%, and 7% (3472 are assumed to be admitted to hospital each year. No cystic fibrosis cases have been recorded. Literature searches on fungal infections revealed few data and no prevalence data on fungal keratitis or tinea capitis, even though tinea capitis comprised 34% of patients with dermatophytoses in Jordan. Results: Jordan has 6.3 million inhabitants (65% adults, 6% are >60 years old. The current burden of serious fungal infections in Jordan was estimated to affect ~119,000 patients (1.9%, not including any cutaneous fungal infections. Candidemia was estimated at 316 cases and invasive aspergillosis in leukemia, transplant, and COPD patients at 84 cases. Chronic pulmonary aspergillosis prevalence was estimated to affect 36 post-TB patients, and 175 in total. Allergic bronchopulmonary aspergillosis (ABPA and severe asthma with fungal sensitization (SAFS prevalence in adults with asthma were estimated at 8900 and 11,748 patients. Recurrent vulvovaginal candidiasis was estimated to affect 97,804 patients, using a 6

  2. Presentation and management of allergic fungal sinusitis

    International Nuclear Information System (INIS)

    Thahim, K.; Jawaid, M.A.; Marfani, S.

    2007-01-01

    To assess the presentation of allergic fungal sinusitis and describe the line of management in our setup. Culture and sensitivity / fungal stain proven 20 cases of allergic fungal sinusitis were selected for the study, irrespective of age and gender. Data including age, gender, socioeconomic status, signs, symptoms, laboratory findings (especially Immunoglobulin E and eosinophil count) and imaging studies (Computed Tomography and /or Magnetic Resonance Imaging) were noted for the study. Pre and postoperative medical treatment, surgery performed, follow-up; residual/recurrence disease and revised surgery performed were also recorded. In this series, allergic fungal sinusitis was a disease of younger age group with an average age of 20.75 years with male dominance (70%). Poor socioeconomic status (80%), allergic rhinitis (100%) and nasal polyposis (100%) were important associated factors. Nasal obstruction (100%), nasal discharge (90%), postnasal drip (90%) and unilateral nasal and paranasal sinuses involvement (60%) were the commonest presenting features. Aspergillus (60%) was the most common etiological agent. In all cases (100%), increased eosinophil count and IgE levels were present. Orbital (20%) and intracranial (10%) involvement were also seen. Surgical management was preferred in all cases. Functional endoscopic sinus surgery in 90% cases and lateral rhinotomy in 10% cases were performed. Recurrence / residual disease was seen in 20% cases. In this series, allergic fungal sinusitis was seen in immunocompetent, young males, belonging to poor socioeconomic status, suffering from allergic rhinitis and nasal polyposis, presenting with nasal obstruction, nasal discharge and postnasal drip. Functional endoscopic sinus surgery was the most important problem solving procedure while lateral rhinotomy was reserved for extensive disease. (author)

  3. Comparison of Nitrogen Depletion and Repletion on Lipid Production in Yeast and Fungal Species

    Directory of Open Access Journals (Sweden)

    Shihui Yang

    2016-08-01

    Full Text Available Although it is well known that low nitrogen stimulates lipid accumulation, especially for algae and some oleaginous yeast, few studies have been conducted in fungal species, especially on the impact of different nitrogen deficiency strategies. In this study, we use two promising consolidated bioprocessing (CBP candidates to examine the impact of two nitrogen deficiency strategies on lipid production, which are the extensively investigated oleaginous yeast Yarrowia lipolytica, and the commercial cellulase producer Trichoderma reesei. We first utilized bioinformatics approaches to reconstruct the fatty acid metabolic pathway and demonstrated the presence of a triacylglycerol (TAG biosynthesis pathway in Trichoderma reesei. We then examined the lipid production of Trichoderma reesei and Y. lipomyces in different media using two nitrogen deficiency strategies of nitrogen natural repletion and nitrogen depletion through centrifugation. Our results demonstrated that nitrogen depletion was better than nitrogen repletion with about 30% lipid increase for Trichoderma reesei and Y. lipomyces, and could be an option to improve lipid production in both oleaginous yeast and filamentous fungal species. The resulting distinctive lipid composition profiles indicated that the impacts of nitrogen depletion on yeast were different from those for fungal species. Under three types of C/N ratio conditions, C16 and C18 fatty acids were the predominant forms of lipids for both Trichoderma reesei and Y. lipolytica. While the overall fatty acid methyl ester (FAME profiles of Trichoderma reesei were similar, the overall FAME profiles of Y. lipolytica observed a shift. The fatty acid metabolic pathway reconstructed in this work supports previous reports of lipid production in T. reesei, and provides a pathway for future omics studies and metabolic engineering efforts. Further investigation to identify the genetic targets responsible for the effect of nitrogen depletion on

  4. Fungal endophytes which invade insect galls: insect pathogens, benign saprophytes, or fungal inquilines?

    Science.gov (United States)

    Wilson, Dennis

    1995-08-01

    Fungi are frequently found within insect galls. However, the origin of these fungi, whether they are acting as pathogens, saprophytes invading already dead galls, or fungal inquilines which invade the gall but kill the gall maker by indirect means, is rarely investigated. A pathogenic role for these fungi is usually inferred but never tested. I chose the following leaf-galling-insect/host-plant pairs (1) a cynipid which forms two-chambered galls on the veins of Oregon white oak, (2) a cynipid which forms single-chambered galls on California coast live oak, and (3) an aphid which forms galls on narrowleaf cottonwood leaves. All pairs were reported to have fungi associated with dead insects inside the gall. These fungi were cultured and identified. For the two cynipids, all fungi found inside the galls were also present in the leaves as fungal endophytes. The cottonwood leaves examined did not harbor fungal endophytes. For the cynipid on Oregon white oak, the fungal endophyte grows from the leaf into the gall and infects all gall tissue but does not directly kill the gall maker. The insect dies as a result of the gall tissue dying from fungal infection. Therefore, the fungus acts as an inquiline. Approximately 12.5% of these galls die as a result of invasion by the fungal endophyte.

  5. Prunus domestica pathogenesis-related protein-5 activates the defense response pathway and enhances the resistance to fungal infection.

    Directory of Open Access Journals (Sweden)

    Ashraf El-kereamy

    Full Text Available Pathogenesis-related protein-5 (PR-5 has been implicated in plant disease resistance and its antifungal activity has been demonstrated in some fruit species. However, their roles, especially their interactions with the other defense responses in plant cells, are still not fully understood. In this study, we have cloned and characterized a new PR-5 cDNA named PdPR5-1 from the European plum (Prunus domestica. Expression of PdPR5-1 was studied in different cultivars varying in resistance to the brown rot disease caused by the necrotrophic fungus Monilinia fructicola. In addition transgenic Arabidopsis, ectopically expressing PdPR5-1 was used to study its role in other plant defense responses after fungal infection. We show that the resistant cultivars exhibited much higher levels of transcripts than the susceptible cultivars during fruit ripening. However, significant rise in the transcript levels after infection with M. fructicola was observed in the susceptible cultivars too. Transgenic Arabidopsis plants exhibited more resistance to Alternaria brassicicola. Further, there was a significant increase in the transcripts of genes involved in the phenylpropanoid biosynthesis pathway such as phenylalanine ammonia-lyase (PAL and phytoalexin (camalexin pathway leading to an increase in camalexin content after fungal infection. Our results show that PdPR5-1 gene, in addition to its anti-fungal properties, has a possible role in activating other defense pathways, including phytoalexin production.

  6. A link between virulence and homeostatic responses to hypoxia during infection by the human fungal pathogen Cryptococcus neoformans.

    Directory of Open Access Journals (Sweden)

    Cheryl D Chun

    2007-02-01

    Full Text Available Fungal pathogens of humans require molecular oxygen for several essential biochemical reactions, yet virtually nothing is known about how they adapt to the relatively hypoxic environment of infected tissues. We isolated mutants defective in growth under hypoxic conditions, but normal for growth in normoxic conditions, in Cryptococcus neoformans, the most common cause of fungal meningitis. Two regulatory pathways were identified: one homologous to the mammalian sterol-response element binding protein (SREBP cholesterol biosynthesis regulatory pathway, and the other a two-component-like pathway involving a fungal-specific hybrid histidine kinase family member, Tco1. We show that cleavage of the SREBP precursor homolog Sre1-which is predicted to release its DNA-binding domain from the membrane-occurs in response to hypoxia, and that Sre1 is required for hypoxic induction of genes encoding for oxygen-dependent enzymes involved in ergosterol synthesis. Importantly, mutants in either the SREBP pathway or the Tco1 pathway display defects in their ability to proliferate in host tissues and to cause disease in infected mice, linking for the first time to our knowledge hypoxic adaptation and pathogenesis by a eukaryotic aerobe. SREBP pathway mutants were found to be a hundred times more sensitive than wild-type to fluconazole, a widely used antifungal agent that inhibits ergosterol synthesis, suggesting that inhibitors of SREBP processing could substantially enhance the potency of current therapies.

  7. Biosynthesis of Gold Nanoparticles Using Pseudomonas Aeruginosa

    International Nuclear Information System (INIS)

    Abd El-Aziz, M.; Badr, Y.; Mahmoud, M. A.

    2007-01-01

    Pseudomonas aeruginosa were used for extracellular biosynthesis of gold nanoparticles (Au NPs). Consequently, Au NPs were formed due to reduction of gold ion by bacterial cell supernatant of P. aeruginos ATCC 90271, P. aeruginos (2) and P. aeruginos (1). The UV-Vis. and fluorescence spectra of the bacterial as well as chemical prepared Au NPs were recorded. Transmission electron microscopy (TEM) micrograph showed the formation of well-dispersed gold nanoparticles in the range of 15-30 nm. The process of reduction being extracellular and may lead to the development of an easy bioprocess for synthesis of Au NPs

  8. Wybutosine biosynthesis: Structural and mechanistic overview

    Science.gov (United States)

    Perche-Letuvée, Phanélie; Molle, Thibaut; Forouhar, Farhad; Mulliez, Etienne; Atta, Mohamed

    2014-01-01

    Over the last 10 years, significant progress has been made in understanding the genetics, enzymology and structural components of the wybutosine (yW) biosynthetic pathway. These studies have played a key role in expanding our understanding of yW biosynthesis and have revealed unexpected evolutionary ties, which are presently being unraveled. The enzymes catalyzing the 5 steps of this pathway, from genetically encoded guanosine to wybutosine base, provide an ensemble of amazing reaction mechanisms that are to be discussed in this review article. PMID:25629788

  9. Chemical Elicitors of Antibiotic Biosynthesis in Actinomycetes

    Directory of Open Access Journals (Sweden)

    Anton P. Tyurin

    2018-06-01

    Full Text Available Whole genome sequencing of actinomycetes has uncovered a new immense realm of microbial chemistry and biology. Most biosynthetic gene clusters present in genomes were found to remain “silent” under standard cultivation conditions. Some small molecules—chemical elicitors—can be used to induce the biosynthesis of antibiotics in actinobacteria and to expand the chemical diversity of secondary metabolites. Here, we outline a brief account of the basic principles of the search for regulators of this type and their application.

  10. Fungal polyketide azaphilone pigments as future natural food colorants?

    DEFF Research Database (Denmark)

    Mapari, Sameer Shamsuddin; Thrane, Ulf; Meyer, Anne S.

    2010-01-01

    The recent approval of fungal carotenoids as food colorants by the European Union has strengthened the prospects for fungal cell factories for the production of polyketide pigments. Fungal production of colorants has the main advantage of making the manufacturer independent of the seasonal supply...... functionality and to expand the color palette of contemporary natural food colorants.......The recent approval of fungal carotenoids as food colorants by the European Union has strengthened the prospects for fungal cell factories for the production of polyketide pigments. Fungal production of colorants has the main advantage of making the manufacturer independent of the seasonal supply...... of raw materials, thus minimizing batch-to-batch variations. Here, we review the potential of polyketide pigments produced from chemotaxonomically selected non-toxigenic fungal strains (e.g. Penicillium and Epicoccum spp.) to serve as food colorants. We argue that the production of polyketide azaphilone...

  11. Fungal atopy in adult cystic fibrosis.

    LENUS (Irish Health Repository)

    Henry, M

    2012-02-03

    This study set out to estimate the prevalence of atopy to a variety of common ubiquitous fungi, including A. fumigatus, in cystic fibrosis (CF), and to evaluate the investigations by which the diagnosis was made. Particular attention was paid to the usefulness of skin testing and immunoassays in detecting which patients had simple fungal atopy, and which patients were at high risk of developing allergic bronchopulmonary mycoses. This cross-sectional study included 21 adult CF patients and 20 matched controls. Serum samples were taken for the measurement of total serum IgE and specific serum IgE to nine common fungi. Immediate hypersensitivity skin prick testing to each of the fungi was also performed. Simple fungal atopy was described in subjects fulfilling the following criteria: total serum IgE > 100 KU l(-1) with specific radioimmunoassay > or = grade 1 to at least one fungus and a positive skin prick test (SPT) > or = 3 mm to the same fungus. \\'High risk\\' for developing allergic bronchopulmonary mycosis (ABPM) was described in subjects fulfilling the following criteria: total serum IgE > 200 KU l(-1) with specific radioimmunoassay > or = grade 2 to at least one fungus and a positive skin prick test (SPT) > or = 6 mm to the same fungus. The adult CF group had a significantly higher total SPT score (P=0.005) and mean total serum IgE (P<0.05) than controls. Forty-three percent of CF patients fulfilled the criteria for fungal atopy to at least a single fungus. Over half this group had an atopic tendency to more than one fungus. Nineteen percent of the CF group were at least \\'high risk\\' of developing ABPM. Skin prick testing is a better marker of fungal atopy and a better predictor of those adult CF patients at higher risk of developing ABPM than specific radioimmunoassay serum testing. There is a high prevalence of fungal atopy in the adult CF population. Total serum IgE and skin prick testing are good predictors of fungal atopy and help predict those at

  12. Symbiotic fungal associations in 'lower' land plants.

    Science.gov (United States)

    Read, D J; Ducket, J G; Francis, R; Ligron, R; Russell, A

    2000-06-29

    An analysis of the current state of knowledge of symbiotic fungal associations in 'lower' plants is provided. Three fungal phyla, the Zygomycota, Ascomycota and Basidiomycota, are involved in forming these associations, each producing a distinctive suite of structural features in well-defined groups of 'lower' plants. Among the 'lower' plants only mosses and Equisetum appear to lack one or other of these types of association. The salient features of the symbioses produced by each fungal group are described and the relationships between these associations and those formed by the same or related fungi in 'higher' plants are discussed. Particular consideration is given to the question of the extent to which root fungus associations in 'lower' plants are analogous to 'mycorrhizas' of 'higher' plants and the need for analysis of the functional attributes of these symbioses is stressed. Zygomycetous fungi colonize a wide range of extant lower land plants (hornworts, many hepatics, lycopods, Ophioglossales, Psilotales and Gleicheniaceae), where they often produce structures analogous to those seen in the vesicular-arbuscular (VA) mycorrhizas of higher plants, which are formed by members of the order Glomales. A preponderance of associations of this kind is in accordance with palaeohbotanical and molecular evidence indicating that glomalean fungi produced the archetypal symbioses with the first plants to emerge on to land. It is shown, probably for the first time, that glomalean fungi forming typical VA mycorrhiza with a higher plant (Plantago lanceolata) can colonize a thalloid liverwort (Pellia epiphylla), producing arbuscules and vesicles in the hepatic. The extent to which these associations, which are structurally analogous to mycorrhizas, have similar functions remains to be evaluated. Ascomycetous associations are found in a relatively small number of families of leafy liverworts. The structural features of the fungal colonization of rhizoids and underground axes of

  13. Transplant tourism and invasive fungal infection

    Directory of Open Access Journals (Sweden)

    I. Al Salmi

    2018-04-01

    Full Text Available Background: Deceased and live-related renal transplants (RTXs are approved procedures that are performed widely throughout the world. In certain regions, commercial RTX has become popular, driven by financial greed. Methods: This retrospective, descriptive study was performed at the Royal Hospital from 2013 to 2015. Data were collected from the national kidney transplant registry of Oman. All transplant cases retrieved were divided into two groups: live-related RTX performed in Oman and commercial-unrelated RTX performed abroad. These groups were then divided again into those with and without evidence of fungal infection, either in the wound or renal graft. Results: A total of 198 RTX patients were identified, of whom 162 (81.8% had undergone a commercial RTX that was done abroad. Invasive fungal infections (IFIs were diagnosed in 8% of patients who had undergone a commercial RTX; of these patients, 76.9% underwent a nephrectomy and 23.1% continued with a functioning graft. None of the patients with RTXs performed at the Royal Hospital contracted an IFI. The most common fungal isolates were Aspergillus species (including Aspergillus flavus, Aspergillus fumigatus, Aspergillus nidulans, and Aspergillus nigricans, followed by Zygomycetes. However, there was no evidence of fungal infection including Aspergillus outside the graft site. Computed tomography (CT findings showed infarction of the graft, renal artery thrombosis, aneurysmal dilatation of the external iliac artery, fungal ball, or just the presence of a perigraft collection. Of the total patients with IFIs, 23.1% died due to septic shock and 53.8% were alive and on hemodialysis. The remaining 23.1% who did not undergo nephrectomy demonstrated acceptable graft function. Conclusions: This is the largest single-center study on commercial RTX reporting the highest number of patients with IFI acquired over a relatively short period of time. Aspergillus spp were the main culprit fungi, with no

  14. Monoterpene biosynthesis potential of plant subcellular compartments.

    Science.gov (United States)

    Dong, Lemeng; Jongedijk, Esmer; Bouwmeester, Harro; Van Der Krol, Alexander

    2016-01-01

    Subcellular monoterpene biosynthesis capacity based on local geranyl diphosphate (GDP) availability or locally boosted GDP production was determined for plastids, cytosol and mitochondria. A geraniol synthase (GES) was targeted to plastids, cytosol, or mitochondria. Transient expression in Nicotiana benthamiana indicated local GDP availability for each compartment but resulted in different product levels. A GDP synthase from Picea abies (PaGDPS1) was shown to boost GDP production. PaGDPS1 was also targeted to plastids, cytosol or mitochondria and PaGDPS1 and GES were coexpressed in all possible combinations. Geraniol and geraniol-derived products were analyzed by GC-MS and LC-MS, respectively. GES product levels were highest for plastid-targeted GES, followed by mitochondrial- and then cytosolic-targeted GES. For each compartment local boosting of GDP biosynthesis increased GES product levels. GDP exchange between compartments is not equal: while no GDP is exchanged from the cytosol to the plastids, 100% of GDP in mitochondria can be exchanged to plastids, while only 7% of GDP from plastids is available for mitochondria. This suggests a direct exchange mechanism for GDP between plastids and mitochondria. Cytosolic PaGDPS1 competes with plastidial GES activity, suggesting an effective drain of isopentenyl diphosphate from the plastids to the cytosol. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  15. Fatty acid biosynthesis in pea root plastids

    International Nuclear Information System (INIS)

    Stahl, R.J.; Sparace, S.A.

    1989-01-01

    Fatty acid biosynthesis from [1- 14 C]acetate was optimized in plastids isolated from primary root tips of 7-day-old germinating pea seeds. Fatty acid synthesis was maximum at approximately 80 nmoles/hr/mg protein in the presence of 200 μM acetate, 0.5 mM each of NADH, NADPH and CoA, 6 mM each of ATP and MgCl 2 , 1 mM each of the MnCl 2 and glycerol-3-phosphate, 15 mM KHCO 3 , and 0.1M Bis-tris-propane, pH 8.0 incubated at 35C. At the standard incubation temperature of 25C, fatty acid synthesis was linear from up to 6 hours with 80 to 100 μg/mL plastid protein. ATP and CoA were absolute requirements, whereas KHCO 3 , divalent cations and reduced nucleotides all improved activity by 80 to 85%. Mg 2+ and NADH were the preferred cation and nucleotide, respectively. Dithiothreitol and detergents were generally inhibitory. The radioactive products of fatty acid biosynthesis were approximately 33% 16:0, 10% 18:0 and 56% 18:1 and generally did not vary with increasing concentrations of each cofactor

  16. Molecular Regulation of Antibiotic Biosynthesis in Streptomyces

    Science.gov (United States)

    Liu, Gang; Chandra, Govind; Niu, Guoqing

    2013-01-01

    SUMMARY Streptomycetes are the most abundant source of antibiotics. Typically, each species produces several antibiotics, with the profile being species specific. Streptomyces coelicolor, the model species, produces at least five different antibiotics. We review the regulation of antibiotic biosynthesis in S. coelicolor and other, nonmodel streptomycetes in the light of recent studies. The biosynthesis of each antibiotic is specified by a large gene cluster, usually including regulatory genes (cluster-situated regulators [CSRs]). These are the main point of connection with a plethora of generally conserved regulatory systems that monitor the organism's physiology, developmental state, population density, and environment to determine the onset and level of production of each antibiotic. Some CSRs may also be sensitive to the levels of different kinds of ligands, including products of the pathway itself, products of other antibiotic pathways in the same organism, and specialized regulatory small molecules such as gamma-butyrolactones. These interactions can result in self-reinforcing feed-forward circuitry and complex cross talk between pathways. The physiological signals and regulatory mechanisms may be of practical importance for the activation of the many cryptic secondary metabolic gene cluster pathways revealed by recent sequencing of numerous Streptomyces genomes. PMID:23471619

  17. Benzylisoquinoline alkaloid biosynthesis in opium poppy.

    Science.gov (United States)

    Beaudoin, Guillaume A W; Facchini, Peter J

    2014-07-01

    Opium poppy (Papaver somniferum) is one of the world's oldest medicinal plants and remains the only commercial source for the narcotic analgesics morphine, codeine and semi-synthetic derivatives such as oxycodone and naltrexone. The plant also produces several other benzylisoquinoline alkaloids with potent pharmacological properties including the vasodilator papaverine, the cough suppressant and potential anticancer drug noscapine and the antimicrobial agent sanguinarine. Opium poppy has served as a model system to investigate the biosynthesis of benzylisoquinoline alkaloids in plants. The application of biochemical and functional genomics has resulted in a recent surge in the discovery of biosynthetic genes involved in the formation of major benzylisoquinoline alkaloids in opium poppy. The availability of extensive biochemical genetic tools and information pertaining to benzylisoquinoline alkaloid metabolism is facilitating the study of a wide range of phenomena including the structural biology of novel catalysts, the genomic organization of biosynthetic genes, the cellular and sub-cellular localization of biosynthetic enzymes and a variety of biotechnological applications. In this review, we highlight recent developments and summarize the frontiers of knowledge regarding the biochemistry, cellular biology and biotechnology of benzylisoquinoline alkaloid biosynthesis in opium poppy.

  18. Essences in Metabolic Engineering of Lignan Biosynthesis

    Directory of Open Access Journals (Sweden)

    Honoo Satake

    2015-05-01

    Full Text Available Lignans are structurally and functionally diverse phytochemicals biosynthesized in diverse plant species and have received wide attentions as leading compounds of novel drugs for tumor treatment and healthy diets to reduce of the risks of lifestyle-related non-communicable diseases. However, the lineage-specific distribution and the low-amount of production in natural plants, some of which are endangered species, hinder the efficient and stable production of beneficial lignans. Accordingly, the development of new procedures for lignan production is of keen interest. Recent marked advances in the molecular and functional characterization of lignan biosynthetic enzymes and endogenous and exogenous factors for lignan biosynthesis have suggested new methods for the metabolic engineering of lignan biosynthesis cascades leading to the efficient, sustainable, and stable lignan production in plants, including plant cell/organ cultures. Optimization of light conditions, utilization of a wide range of elicitor treatments, and construction of transiently gene-transfected or transgenic lignan-biosynthesizing plants are mainly being attempted. This review will present the basic and latest knowledge regarding metabolic engineering of lignans based on their biosynthetic pathways and biological activities, and the perspectives in lignan production via metabolic engineering.

  19. Biosynthesis of nanoparticles using microbes- a review.

    Science.gov (United States)

    Hulkoti, Nasreen I; Taranath, T C

    2014-09-01

    The biosynthesis of nanoparticles by microorganism is a green and eco-friendly technology. This review focuses on the use of consortium of diverse microorganisms belonging to both prokaryotes and eukaryotes for the synthesis of metallic nanoparticles viz. silver, gold, platinum, zirconium, palladium, iron, cadmium and metal oxides such as titanium oxide, zinc oxide, etc. These microorganisms include bacteria, actinomycetes, fungi and algae. The synthesis of nanoparticles may be intracellular or extracellular. The several workers have reported that NADH dependent nitrate reductase enzyme plays a vital role in the conversion of metallic ions to nanoparticles. The FTIR study reveals that diverse biomolecules viz. carboxyl group, primary and secondary amines, amide I, II, and III bands etc serve as a tool for bioreduction and capping agents there by offering stability to particles by preventing agglomeration and growth. The size and shape of the nanoparticles vary with the organism employed and conditions employed during the synthesis which included pH, temperature and substrate concentration. The microorganisms provide diverse environment for biosynthesis of nanoparticles. These particles are safe and eco-friendly with a lot of applications in medicine, agriculture, cosmetic industry, drug delivery and biochemical sensors. The challenges for redressal include optimal production and minimal time to obtain desired size and shape, to enhance the stability of nanoparticles and optimization of specific microorganisms for specific application. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Metabolic plasticity for isoprenoid biosynthesis in bacteria.

    Science.gov (United States)

    Pérez-Gil, Jordi; Rodríguez-Concepción, Manuel

    2013-05-15

    Isoprenoids are a large family of compounds synthesized by all free-living organisms. In most bacteria, the common precursors of all isoprenoids are produced by the MEP (methylerythritol 4-phosphate) pathway. The MEP pathway is absent from archaea, fungi and animals (including humans), which synthesize their isoprenoid precursors using the completely unrelated MVA (mevalonate) pathway. Because the MEP pathway is essential in most bacterial pathogens (as well as in the malaria parasites), it has been proposed as a promising new target for the development of novel anti-infective agents. However, bacteria show a remarkable plasticity for isoprenoid biosynthesis that should be taken into account when targeting this metabolic pathway for the development of new antibiotics. For example, a few bacteria use the MVA pathway instead of the MEP pathway, whereas others possess the two full pathways, and some parasitic strains lack both the MVA and the MEP pathways (probably because they obtain their isoprenoids from host cells). Moreover, alternative enzymes and metabolic intermediates to those of the canonical MVA or MEP pathways exist in some organisms. Recent work has also shown that resistance to a block of the first steps of the MEP pathway can easily be developed because several enzymes unrelated to isoprenoid biosynthesis can produce pathway intermediates upon spontaneous mutations. In the present review, we discuss the major advances in our knowledge of the biochemical toolbox exploited by bacteria to synthesize the universal precursors for their essential isoprenoids.

  1. Brassinosteroid biosynthesis and signalling in Petunia hybrida.

    Science.gov (United States)

    Verhoef, Nathalie; Yokota, Takao; Shibata, Kyomi; de Boer, Gert-Jan; Gerats, Tom; Vandenbussche, Michiel; Koes, Ronald; Souer, Erik

    2013-05-01

    Brassinosteroids (BRs) are steroidal plant hormones that play an important role in the growth and development of plants. The biosynthesis of sterols and BRs as well as the signalling cascade they induce in plants have been elucidated largely through metabolic studies and the analysis of mutants in Arabidopsis and rice. Only fragmentary details about BR signalling in other plant species are known. Here a forward genetics strategy was used in Petunia hybrida, by which 19 families with phenotypic alterations typical for BR deficiency mutants were identified. In all mutants, the endogenous BR levels were severely reduced. In seven families, the tagged genes were revealed as the petunia BR biosynthesis genes CYP90A1 and CYP85A1 and the BR receptor gene BRI1. In addition, several homologues of key regulators of the BR signalling pathway were cloned from petunia based on homology with their Arabidopsis counterparts, including the BRI1 receptor, a member of the BES1/BZR1 transcription factor family (PhBEH2), and two GSK3-like kinases (PSK8 and PSK9). PhBEH2 was shown to interact with PSK8 and 14-3-3 proteins in yeast, revealing similar interactions to those during BR signalling in Arabidopsis. Interestingly, PhBEH2 also interacted with proteins implicated in other signalling pathways. This suggests that PhBEH2 might function as an important hub in the cross-talk between diverse signalling pathways.

  2. BIOSYNTHESIS AND ACTION OF JASMONATES IN PLANTS.

    Science.gov (United States)

    Creelman, Robert A.; Mullet, John E.

    1997-06-01

    Jasmonic acid and its derivatives can modulate aspects of fruit ripening, production of viable pollen, root growth, tendril coiling, and plant resistance to insects and pathogens. Jasmonate activates genes involved in pathogen and insect resistance, and genes encoding vegetative storage proteins, but represses genes encoding proteins involved in photosynthesis. Jasmonic acid is derived from linolenic acid, and most of the enzymes in the biosynthetic pathway have been extensively characterized. Modulation of lipoxygenase and allene oxide synthase gene expression in transgenic plants raises new questions about the compartmentation of the biosynthetic pathway and its regulation. The activation of jasmonic acid biosynthesis by cell wall elicitors, the peptide systemin, and other compounds will be related to the function of jasmonates in plants. Jasmonate modulates gene expression at the level of translation, RNA processing, and transcription. Promoter elements that mediate responses to jasmonate have been isolated. This review covers recent advances in our understanding of how jasmonate biosynthesis is regulated and relates this information to knowledge of jasmonate modulated gene expression.

  3. Rapid biosynthesis of cadmium sulfide (CdS) nanoparticles using ...

    African Journals Online (AJOL)

    Rapid biosynthesis of cadmium sulfide (CdS) nanoparticles using culture supernatants of Escherichia coli ATCC 8739, Bacillus subtilis ATCC 6633 and Lactobacillus ... The process of extracellular and fast biosynthesis may help in the development of an easy and eco-friendly route for the synthesis of CdS nanoparticles.

  4. Rare cause of post-squalene disorder of cholesterol biosynthesis ...

    African Journals Online (AJOL)

    Errors of cholesterol biosynthesis represent a heterogeneous group of metabolic disorders. The aim of the authors of this article is to present a case of a patient with typical symptoms of a rare post-squalene disorder of cholesterol biosynthesis, its diagnostics and progress in neonatal period. The differential diagnosis of a ...

  5. Isoprenoid biosynthesis in hereditary periodic fever syndromes and inflammation

    NARCIS (Netherlands)

    Houten, S. M.; Frenkel, J.; Waterham, H. R.

    2003-01-01

    Mevalonate kinase (MK) is an essential enzyme in the isoprenoid biosynthesis pathway which produces numerous biomolecules (isoprenoids) involved in a variety of cellular processes. The indispensability of MK and isoprenoid biosynthesis for human health is demonstrated by the identification of its

  6. Fiber, food, fuel, and fungal symbionts.

    Science.gov (United States)

    Ruehle, J L; Marx, D H

    1979-10-26

    Virtually all plants of economic importance form mycorrhizae. These absorbing organs of higher plants result from a symbiotic union of beneficial soil fungi and feeder roots. In forestry, the manipulation of fungal symbionts ecologically adapted to the planting site can increase survival and growth of forest trees, particularly on adverse sites. Vesicular-arbuscular mycorrhizae, which occur not only on many trees but also on most cultivated crops, are undoubtedly more important to world food crops. Imperatives for mycorrhizal research in forestry and agriculture are (i) the development of mass inoculum of mycorrhizal fungi, (ii) the interdisciplinary coordination with soil management, plant breeding, cultivation practices, and pest control to ensure maximum survival and development of fungal symbionts in the soil, and (iii) the institution of nursery and field tests to determine the circumstances in which mycorrhizae benefit plant growth in forestry and agri-ecosystems.

  7. Fungal enzymes in the attine ant symbiosis

    DEFF Research Database (Denmark)

    de Fine Licht, Henrik Hjarvard; Schiøtt, Morten; Boomsma, Jacobus Jan

    the more basal attine genera use substrates such as flowers, plant debris, small twigs, insect feces and insect carcasses. This diverse array of fungal substrates across the attine lineage implies that the symbiotic fungus needs different enzymes to break down the plant material that the ants provide...... or different efficiencies of enzyme function. Fungal enzymes that degrade plant cell walls may have functionally co-evolved with the ants in this scenario. We explore this hypothesis with direct measurements of enzyme activity in fungus gardens in 12 species across 8 genera spanning the entire phylogeny...... and diversity of life-styles within the attine clade. We find significant differences in enzyme activity between different genera and life-styles of the ants. How these findings relate to attine ant coevolution and crop optimization are discussed....

  8. Sesquiterpene Synthase-3-Hydroxy-3-Methylglutaryl Coenzyme A Synthase Fusion Protein Responsible for Hirsutene Biosynthesis in Stereum hirsutum.

    Science.gov (United States)

    Flynn, Christopher M; Schmidt-Dannert, Claudia

    2018-06-01

    The wood-rotting mushroom Stereum hirsutum is a known producer of a large number of namesake hirsutenoids, many with important bioactivities. Hirsutenoids form a structurally diverse and distinct class of sesquiterpenoids. No genes involved in hirsutenoid biosynthesis have yet been identified or their enzymes characterized. Here, we describe the cloning and functional characterization of a hirsutene synthase as an unexpected fusion protein of a sesquiterpene synthase (STS) with a C-terminal 3-hydroxy-3-methylglutaryl-coenzyme A (3-hydroxy-3-methylglutaryl-CoA) synthase (HMGS) domain. Both the full-length fusion protein and truncated STS domain are highly product-specific 1,11-cyclizing STS enzymes with kinetic properties typical of STSs. Complementation studies in Saccharomyces cerevisiae confirmed that the HMGS domain is also functional in vivo Phylogenetic analysis shows that the hirsutene synthase domain does not form a clade with other previously characterized sesquiterpene synthases from Basidiomycota. Comparative gene structure analysis of this hirsutene synthase with characterized fungal enzymes reveals a significantly higher intron density, suggesting that this enzyme may be acquired by horizontal gene transfer. In contrast, the HMGS domain is clearly related to other fungal homologs. This STS-HMGS fusion protein is part of a biosynthetic gene cluster that includes P450s and oxidases that are expressed and could be cloned from cDNA. Finally, this unusual fusion of a terpene synthase to an HMGS domain, which is not generally recognized as a key regulatory enzyme of the mevalonate isoprenoid precursor pathway, led to the identification of additional HMGS duplications in many fungal genomes, including the localization of HMGSs in other predicted sesquiterpenoid biosynthetic gene clusters. IMPORTANCE Hirsutenoids represent a structurally diverse class of bioactive sesquiterpenoids isolated from fungi. Identification of their biosynthetic pathways will provide

  9. Burden of serious fungal infections in Bangladesh.

    Science.gov (United States)

    Gugnani, H C; Denning, D W; Rahim, R; Sadat, A; Belal, M; Mahbub, M S

    2017-06-01

    In Bangladesh there are several published papers on superficial mycoses. Deep mycoses are also recognized as an important emerging problem. Here, we estimate the annual incidence and prevalence of serious fungal infections in Bangladesh. Demographic data were obtained from world population reports and the data on TB and HIV extracted from the online publications on tuberculosis in Bangladesh and Asia Pacific research statistical data information resources AIDS Data HUB. All the published papers on fungal infections in Bangladesh were identified through extensive search of literature. We estimated the number of affected people from populations at risk and local epidemiological data. Bangladesh has a population of ∼162.6 million, 31% children and only 6% over the age of 60 years. The pulmonary TB caseload reported in 2014 was 119,520, and we estimate a prevalence of 30,178 people with chronic pulmonary aspergillosis, 80% attributable to TB. An anticipated 90,262 and 119,146 patients have allergic bronchopulmonary aspergillosis or severe asthma with fungal sensitization. Only 8,000 people are estimated to be HIV-infected, of whom 2900 are not on ART with a CD4 count Bangladesh. Candida bloodstream infection was estimated based on a 5 per 100,000 rate (8100 cases) and invasive aspergillosis based primarily on leukemia and COPD rates, at 5166 cases. Histoplasmosis was documented in 16 cases mostly with disseminated disease and presumed in 21 with HIV infection. This study constitutes the first attempt to estimate the burden of several types of serious fungal infections in Bangladesh.

  10. Burden of serious fungal infections in Ukraine.

    Science.gov (United States)

    Osmanov, Ali; Denning, David W

    2015-10-01

    Ukraine has high rates of TB, AIDS and cancer. We estimated the burden of fungal disease from epidemiology papers and specific populations at risk and fungal infection frequencies. HIV/AIDS cases and deaths (2012) and tuberculosis statistics were obtained from the State Service of Ukraine, while chronic obstructive pulmonary disease (COPD) cases were from M. Miravitlles et al., Thorax 64, 863-868 (2009). Annual estimates are 893,579 Ukrainian women get recurrent vaginal thrush (≥4× per year), 50,847 cases of oral candidiasis and 13,727 cases of oesophageal candidiasis in HIV, and 101 (1%) of 10,085 new AIDS cases develop cryptococcal meningitis, 6152 cases of Pneumocystis pneumonia (13.5 cases per 100,000). Of the 29,265 cases of active respiratory TB in 2012, it is estimated that 2881 new cases of chronic pulmonary aspergillosis (CPA) occurred and that the 5-year period prevalence is 7724 cases with a total CPA burden of 10,054 cases. Assuming adult asthma prevalence is ~2.9%, 28,447 patients with allergic bronchopulmonary aspergillosis (ABPA) are likely and 37,491 with severe asthma with fungal sensitisation. We estimate 2278 cases and 376 postsurgical intra-abdominal Candida infections. Invasive aspergillosis in immunocompromised patients is estimated at 303 patients annually; 930 cases in COPD patients. Ninety cases of mucormycosis (2 per 1,000,000) are estimated. In total, ~1,000,000 (2.2%) people in Ukraine develop serious fungal infections annually. © 2015 Blackwell Verlag GmbH.

  11. Fungal Anticancer Metabolites: Synthesis Towards Drug Discovery.

    Science.gov (United States)

    Barbero, Margherita; Artuso, Emma; Prandi, Cristina

    2018-01-01

    Fungi are a well-known and valuable source of compounds of therapeutic relevance, in particular of novel anticancer compounds. Although seldom obtainable through isolation from the natural source, the total organic synthesis still remains one of the most efficient alternatives to resupply them. Furthermore, natural product total synthesis is a valuable tool not only for discovery of new complex biologically active compounds but also for the development of innovative methodologies in enantioselective organic synthesis. We undertook an in-depth literature searching by using chemical bibliographic databases (SciFinder, Reaxys) in order to have a comprehensive insight into the wide research field. The literature has been then screened, refining the obtained results by subject terms focused on both biological activity and innovative synthetic procedures. The literature on fungal metabolites has been recently reviewed and these publications have been used as a base from which we consider the synthetic feasibility of the most promising compounds, in terms of anticancer properties and drug development. In this paper, compounds are classified according to their chemical structure. This review summarizes the anticancer potential of fungal metabolites, highlighting the role of total synthesis outlining the feasibility of innovative synthetic procedures that facilitate the development of fungal metabolites into drugs that may become a real future perspective. To our knowledge, this review is the first effort to deal with the total synthesis of these active fungi metabolites and demonstrates that total chemical synthesis is a fruitful means of yielding fungal derivatives as aided by recent technological and innovative advancements. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  12. Bacterial, Fungal, Parasitic, and Viral Myositis

    OpenAIRE

    Crum-Cianflone, Nancy F.

    2008-01-01

    Infectious myositis may be caused by a broad range of bacterial, fungal, parasitic, and viral agents. Infectious myositis is overall uncommon given the relative resistance of the musculature to infection. For example, inciting events, including trauma, surgery, or the presence of foreign bodies or devitalized tissue, are often present in cases of bacterial myositis. Bacterial causes are categorized by clinical presentation, anatomic location, and causative organisms into the categories of pyo...

  13. Fungal Systematics and Evolution: FUSE 1

    OpenAIRE

    Crous, Pedro W; Schumacher, René K; Wingfield, Michael J; Lombard, Lorenzo; Giraldo, Alejandra; Christensen, Martha; Gardiennet, Alain; Nakashima, Chiharu; Pereira, Olinto L; Smith, Alexander J; Groenewald, Johannes Z

    2015-01-01

    Fungal Systematics and Evolution (FUSE) is introduced as a new series to expedite the publication of issues relating to the epitypification of formerly described species, report new sexual-asexual connections, the merging of sexual and asexual gen¬era following the end of dual nomenclature, and to describe species or note interesting observations regarding fungi. This first paper includes 18 new combinations, 13 new species, three new genera and one new family. All taxa are ascomycetes, excep...

  14. Invasive fungal infections in endogenous Cushing's syndrome

    Science.gov (United States)

    Scheffel, Rafael Selbach; Dora, José Miguel; Weinert, Letícia Schwerz; Aquino, Valério; Maia, Ana Luiza; Canani, Luis Henrique; Goldani, Luciano Z.

    2010-01-01

    Cushing's syndrome is a condition characterized by elevated cortisol levels that can result from either augmented endogenous production or exogenous administration of corticosteroids. The predisposition to fungal infections among patients with hypercortisolemia has been noted since Cushing's original description of the disease. We describe here a patient with endogenous Cushing's syndrome secondary to an adrenocortical carcinoma, who developed concomitant disseminated cryptococcosis and candidiasis in the course of his disease. PMID:24470886

  15. Burden of Serious Fungal Infections in Argentina

    Directory of Open Access Journals (Sweden)

    Fernando O. Riera

    2018-04-01

    Full Text Available The number of fungal infections at any given time in Argentina is not known. Here we estimate the burden of serious fungal infections in Argentina for the first time. Specific population statistics were searched from multiple sources, local literature was identified, and estimates made. Some additional data were sourced from the Ministry of Health, the Global Initiative for Asthma (GINA program, and national haematology and transplant societies. Argentina has a population of 43.8 million, with 25% of this total being children under 15 years. The predicted candidemia annual incidence is 2193 cases, with 50% occurring in the ICU. At a 6% prevalence rate, an estimated 593,695 women suffer from recurrent vulvovaginal candidiasis. Invasive aspergillosis is relatively common because of high smoking and chronic obstructive pulmonary disease (COPD rates, with 268 cases in immunocompromised patients and another 1938 in the 168,000 COPD patients admitted to hospital. Asthma is also common, affecting 14% of adults, and so allergic bronchopulmonary aspergillosis (ABPA and severe asthma with fungal sensitization (SAFS are major problems. An estimated 432 cases of cryptococcal meningitis (CM—90% of them in AIDS patients—and 1177 cases of Pneumocystis pneumonia (PCP occur each year. The estimated annual case number of disseminated histoplasmosis is 404 in AIDS patients, almost as frequent as CM. Paracoccidioidomycosis annual incidence is estimated at 219, and coccidioidomycosis at 16 cases. At least 881,023 people (>2.01% in Argentina are affected by a serious fungal disease annually, with considerable morbidity and mortality.

  16. Structural and functional studies of a phosphatidic acid-binding antifungal plant defensin MtDef4: identification of an RGFRRR motif governing fungal cell entry.

    Directory of Open Access Journals (Sweden)

    Uma Shankar Sagaram

    Full Text Available MtDef4 is a 47-amino acid cysteine-rich evolutionary conserved defensin from a model legume Medicago truncatula. It is an apoplast-localized plant defense protein that inhibits the growth of the ascomycetous fungal pathogen Fusarium graminearum in vitro at micromolar concentrations. Little is known about the mechanisms by which MtDef4 mediates its antifungal activity. In this study, we show that MtDef4 rapidly permeabilizes fungal plasma membrane and is internalized by the fungal cells where it accumulates in the cytoplasm. Furthermore, analysis of the structure of MtDef4 reveals the presence of a positively charged γ-core motif composed of β2 and β3 strands connected by a positively charged RGFRRR loop. Replacement of the RGFRRR sequence with AAAARR or RGFRAA abolishes the ability of MtDef4 to enter fungal cells, suggesting that the RGFRRR loop is a translocation signal required for the internalization of the protein. MtDef4 binds to phosphatidic acid (PA, a precursor for the biosynthesis of membrane phospholipids and a signaling lipid known to recruit cytosolic proteins to membranes. Amino acid substitutions in the RGFRRR sequence which abolish the ability of MtDef4 to enter fungal cells also impair its ability to bind PA. These findings suggest that MtDef4 is a novel antifungal plant defensin capable of entering into fungal cells and affecting intracellular targets and that these processes are mediated by the highly conserved cationic RGFRRR loop via its interaction with PA.

  17. A Study Of Fungal Colonization In Newborn

    Directory of Open Access Journals (Sweden)

    S Rashid Husain

    1997-04-01

    Full Text Available Research Problem: What are the factors responsible for fungal colonization in newborns? Objective: To study the pattern of and predisposing fac­tors for the development of superficial candidiasis and fungal colonization in the newborns. Study Design: Prospective study. Setting: Neonatology unitof the Paediatrics department of a teaching hospital. Participants: Randomly selected pregnant mothers admit­ted to the maternity ward and the newborns delivered to them. Sample Size: 120 pregnant mothers and the newborns delivered. Study Variables: Candida, Site of colonization. Statistical Analysis: By tests of significance Results: Candida was isolated from 23 (19.16% infants on the first day increasing to 52 (43.33% infants on the sixth day. The most common site of colonization was oral cavity. Candida colonization was more common in prema­ture infants (p<0.05. Oral thrush was seen in 29 (24.17% infants during the study and a significant number of these infants showed colonization from the first day of life. Conclusions: Fungal colonization of the newborns due to Candida species is quite common, and in the first week of life predominantly occurred in the ora I cavity. Superficial clinical candidiasis, especially oral thrush is more common in those colonized on the first day of life.

  18. Fungal myositis in children: serial ultrasonographic findings

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Jung Hwa; Lee, Hee Jung; Choi, Jin Soo [Keimyung University School of Medicine, Daegu (Korea, Republic of)

    2003-08-01

    To evaluate serial ultrasonographic findings of fungal myositis in children. Eleven lesions caused by fungal myositis and occurring in six children were included in this study. Eight lesions in five children were histopathologically proven and the other three were clinically diagnosed. Serial ultrasonographic findings were retrospectively evaluated in terms of size, location, margin, internal echotexture and adjacent cortical change occurring during the follow-up period ranging from five days to two months. Three patients (50%) had multiple lesions. The sites of involvment were the thigh (n=4), calf (n=3), chest wall (n=2), abdominal wall (n=1) and forearm (n=1). Initially, diffuse muscular swelling was revealed, with ill-defined hypoechoic lesions confined to the muscle layer (n=8). Follow-up examination of eight lesions over a period of 5-10 days showed that round central echogenic lesions were surrounded by previous slightly echogenic lesions (n=6, 75%). Long-term follow-up of five lesions over a two-month period revealed periosteal thickening in one case (20%), and the peristence of echogenic solid nodules in four (80%). Pathologic examination showed that the central lesions correlated with a fungus ball and the peripheral slightly echogenic lesions corresponded to hematoma and necrosis. Serial ultrasonographic findings of fungal myositis in children revealed relatively constant features in each case. In particular, the findings of muscular necrosis and a fungus ball over a period of 5-14 days were thought to be characteristic.

  19. Fungal myositis in children: serial ultrasonographic findings

    International Nuclear Information System (INIS)

    Kwon, Jung Hwa; Lee, Hee Jung; Choi, Jin Soo

    2003-01-01

    To evaluate serial ultrasonographic findings of fungal myositis in children. Eleven lesions caused by fungal myositis and occurring in six children were included in this study. Eight lesions in five children were histopathologically proven and the other three were clinically diagnosed. Serial ultrasonographic findings were retrospectively evaluated in terms of size, location, margin, internal echotexture and adjacent cortical change occurring during the follow-up period ranging from five days to two months. Three patients (50%) had multiple lesions. The sites of involvment were the thigh (n=4), calf (n=3), chest wall (n=2), abdominal wall (n=1) and forearm (n=1). Initially, diffuse muscular swelling was revealed, with ill-defined hypoechoic lesions confined to the muscle layer (n=8). Follow-up examination of eight lesions over a period of 5-10 days showed that round central echogenic lesions were surrounded by previous slightly echogenic lesions (n=6, 75%). Long-term follow-up of five lesions over a two-month period revealed periosteal thickening in one case (20%), and the peristence of echogenic solid nodules in four (80%). Pathologic examination showed that the central lesions correlated with a fungus ball and the peripheral slightly echogenic lesions corresponded to hematoma and necrosis. Serial ultrasonographic findings of fungal myositis in children revealed relatively constant features in each case. In particular, the findings of muscular necrosis and a fungus ball over a period of 5-14 days were thought to be characteristic

  20. Bacterial - Fungal Interactions: ecology, mechanisms and challenges.

    Science.gov (United States)

    Deveau, A; Bonito, G; Uehling, J; Paoletti, M; Becker, M; Bindschedler, S; Hacquard, S; Hervé, V; Labbé, J; Lastovetsky, O A; Mieszkin, S; Millet, L J; Vajna, B; Junier, P; Bonfante, P; Krom, B P; Olsson, S; Elsas, J D van; Wick, L Y

    2018-02-19

    Fungi and bacteria are found living together in a wide variety of environments. Their interactions are significant drivers of many ecosystem functions and are important for the health of plants and animals. A large number of fungal and bacterial families are engaged in complex interactions that lead to critical behavioural shifts of the microorganisms ranging from mutualism to pathogenicity. The importance of bacterial-fungal interactions (BFI) in environmental science, medicine and biotechnology has led to the emergence of a dynamic and multidisciplinary research field that combines highly diverse approaches including molecular biology, genomics, geochemistry, chemical and microbial ecology, biophysics and ecological modelling. In this review, we discuss most recent advances that underscore the roles of BFI across relevant habitats and ecosystems. A particular focus is placed on the understanding of BFI within complex microbial communities and in regards of the metaorganism concept. We also discuss recent discoveries that clarify the (molecular) mechanisms involved in bacterial-fungal relationships, and the contribution of new technologies to decipher generic principles of BFI in terms of physical associations and molecular dialogues. Finally, we discuss future directions for researches in order to catalyse a synergy within the BFI research area and to resolve outstanding questions.

  1. Risk of Fungal Infection to Dental Patients

    Directory of Open Access Journals (Sweden)

    Jaqueline Lopes Damasceno

    2017-01-01

    Full Text Available Fungi can cause various diseases, and some pathogenic fungi have been detected in the water of dental equipment. This environment offers suitable conditions for fungal biofilms to emerge, which can facilitate mycological contamination. This study verified whether the water employed in the dental units of two dental clinics at the University of Franca was contaminated with fungi. This study also evaluated the ability of the detected fungi to form biofilms. The high-revving engine contained the largest average amount of fungi, 14.93 ± 18.18 CFU/mL. The main fungal species verified in this equipment belonged to the genera Aspergillus spp., Fusarium spp., Candida spp., and Rhodotorula spp. Among the isolated filamentous fungi, only one fungus of the genus Fusarium spp. did not form biofilms. As for yeasts, all the Candida spp. isolates grew as biofilm, but none of the Rhodotorula spp. isolates demonstrated this ability. Given that professionals and patients are often exposed to water and aerosols generated by the dental procedure, the several fungal species detected herein represent a potential risk especially to immunocompromised patients undergoing dental treatment. Therefore, frequent microbiological monitoring of the water employed in dental equipment is crucial to reduce the presence of contaminants.

  2. Fungal Production and Manipulation of Plant Hormones.

    Science.gov (United States)

    Fonseca, Sandra; Radhakrishnan, Dhanya; Prasad, Kalika; Chini, Andrea

    2018-01-01

    Living organisms are part of a highly interconnected web of interactions, characterised by species nurturing, competing, parasitizing and preying on one another. Plants have evolved cooperative as well as defensive strategies to interact with neighbour organisms. Among these, the plant-fungus associations are very diverse, ranging from pathogenic to mutualistic. Our current knowledge of plant-fungus interactions suggests a sophisticated coevolution to ensure dynamic plant responses to evolving fungal mutualistic/pathogenic strategies. The plant-fungus communication relies on a rich chemical language. To manipulate the plant defence mechanisms, fungi produce and secrete several classes of biomolecules, whose modeof- action is largely unknown. Upon perception of the fungi, plants produce phytohormones and a battery of secondary metabolites that serve as defence mechanism against invaders or to promote mutualistic associations. These mutualistic chemical signals can be co-opted by pathogenic fungi for their own benefit. Among the plant molecules regulating plant-fungus interaction, phytohormones play a critical role since they modulate various aspects of plant development, defences and stress responses. Intriguingly, fungi can also produce phytohormones, although the actual role of fungalproduced phytohormones in plant-fungus interactions is poorly understood. Here, we discuss the recent advances in fungal production of phytohormone, their putative role as endogenous fungal signals and how fungi manipulate plant hormone balance to their benefits. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  3. Structural and functional studies of a phosphatidic acid-binding antifungal plant defensin MtDef4: Identification of an RGFRRR motif governing fungal cell entry

    Energy Technology Data Exchange (ETDEWEB)

    Sagaram, Uma S.; El-Mounadi, Kaoutar; Buchko, Garry W.; Berg, Howard R.; Kaur, Jagdeep; Pandurangi, Raghoottama; Smith, Thomas J.; Shah, Dilip

    2013-12-04

    A highly conserved plant defensin MtDef4 potently inhibits the growth of a filamentous fungus Fusarium graminearum. MtDef4 is internalized by cells of F. graminearum. To determine its mechanism of fungal cell entry and antifungal action, NMR solution structure of MtDef4 has been determined. The analysis of its structure has revealed a positively charged patch on the surface of the protein consisting of arginine residues in its γ-core signature, a major determinant of the antifungal activity of MtDef4. Here, we report functional analysis of the RGFRRR motif of the γ-core signature of MtDef4. The replacement of RGFRRR to AAAARR or to RGFRAA not only abolishes fungal cell entry but also results in loss of the antifungal activity of MtDef4. MtDef4 binds strongly to phosphatidic acid (PA), a precursor for the biosynthesis of membrane phospholipids and a signaling lipid known to recruit cytosolic proteins to membranes. Mutations of RGFRRR which abolish fungal cell entry of MtDef4 also impair its binding to PA. Our results suggest that RGFRRR motif is a translocation signal for entry of MtDef4 into fungal cells and that this positively charged motif likely mediates interaction of this defensin with PA as part of its antifungal action.

  4. Expression of cytokines in aqueous humor from fungal keratitis patients.

    Science.gov (United States)

    Zhang, Yingnan; Liang, Qingfeng; Liu, Yang; Pan, Zhiqiang; Baudouin, Christophe; Labbé, Antoine; Lu, Qingxian

    2018-04-19

    Although a series of reports on corneal fungal infection have been published, studies on pathogenic mechanisms and inflammation-associated cytokines remain limited. In this study, aqueous humor samples from fungal keratitis patients were collected to examine cytokine patterns and cellular profile for the pathogenesis of fungal keratitis. The aqueous humor samples were collected from ten patients with advanced stage fungal keratitis. Eight aqueous humor samples from patients with keratoconus or corneal dystrophy were taken as control. Approximately 100 μl to 300 μl of aqueous humor in each case were obtained for examination. The aqueous humor samples were centrifuged and the cells were stained and examined under optical microscope. Bacterial and fungal cultures were performed on the aqueous humor and corneal buttons of all patients. Cytokines related to inflammation including IL-1β, IL-6, IL-8, IL-10, TNF-α, and IFN-γ were examined using multiplex bead-based Luminex liquid protein array systems. Fungus infection was confirmed in these ten patients by smear stains and/or fungal cultures. Bacterial and fungal cultures revealed negative results in all aqueous humor specimens. Polymorphonuclear leukocytes were the predominant infiltrating cells in the aqueous humor of fungal keratitis. At the advanced stages of fungal keratitis, the levels of IL-1β, IL-6, IL-8, and IFN-γ in the aqueous humor were significantly increased when compared with control (phumor was associated with fungal keratitis.

  5. Enzymes from Fungal and Plant Origin Required for Chemical Diversification of Insecticidal Loline Alkaloids in Grass-Epichloë Symbiota

    Science.gov (United States)

    Pan, Juan; Bhardwaj, Minakshi; Nagabhyru, Padmaja; Grossman, Robert B.; Schardl, Christopher L.

    2014-01-01

    The lolines are a class of bioprotective alkaloids that are produced by Epichloë species, fungal endophytes of grasses. These alkaloids are saturated 1-aminopyrrolizidines with a C2 to C7 ether bridge, and are structurally differentiated by the various modifications of the 1-amino group: -NH2 (norloline), -NHCH3 (loline), -N(CH3)2 (N-methylloline), -N(CH3)Ac (N-acetylloline), -NHAc (N-acetylnorloline), and -N(CH3)CHO (N-formylloline). Other than the LolP cytochrome P450, which is required for conversion of N-methylloline to N-formylloline, the enzymatic steps for loline diversification have not yet been established. Through isotopic labeling, we determined that N-acetylnorloline is the first fully cyclized loline alkaloid, implying that deacetylation, methylation, and acetylation steps are all involved in loline alkaloid diversification. Two genes of the loline alkaloid biosynthesis (LOL) gene cluster, lolN and lolM, were predicted to encode an N-acetamidase (deacetylase) and a methyltransferase, respectively. A knockout strain lacking both lolN and lolM stopped the biosynthesis at N-acetylnorloline, and complementation with the two wild-type genes restored production of N-formylloline and N-acetylloline. These results indicated that lolN and lolM are required in the steps from N-acetylnorloline to other lolines. The function of LolM as an N-methyltransferase was confirmed by its heterologous expression in yeast resulting in conversion of norloline to loline, and of loline to N-methylloline. One of the more abundant lolines, N-acetylloline, was observed in some but not all plants with symbiotic Epichloë siegelii, and when provided with exogenous loline, asymbiotic meadow fescue (Lolium pratense) plants produced N-acetylloline, suggesting that a plant acetyltransferase catalyzes N-acetylloline formation. We conclude that although most loline alkaloid biosynthesis reactions are catalyzed by fungal enzymes, both fungal and plant enzymes are responsible for the

  6. Enzymes from fungal and plant origin required for chemical diversification of insecticidal loline alkaloids in grass-Epichloë symbiota.

    Science.gov (United States)

    Pan, Juan; Bhardwaj, Minakshi; Nagabhyru, Padmaja; Grossman, Robert B; Schardl, Christopher L

    2014-01-01

    The lolines are a class of bioprotective alkaloids that are produced by Epichloë species, fungal endophytes of grasses. These alkaloids are saturated 1-aminopyrrolizidines with a C2 to C7 ether bridge, and are structurally differentiated by the various modifications of the 1-amino group: -NH2 (norloline), -NHCH3 (loline), -N(CH3)2 (N-methylloline), -N(CH3)Ac (N-acetylloline), -NHAc (N-acetylnorloline), and -N(CH3)CHO (N-formylloline). Other than the LolP cytochrome P450, which is required for conversion of N-methylloline to N-formylloline, the enzymatic steps for loline diversification have not yet been established. Through isotopic labeling, we determined that N-acetylnorloline is the first fully cyclized loline alkaloid, implying that deacetylation, methylation, and acetylation steps are all involved in loline alkaloid diversification. Two genes of the loline alkaloid biosynthesis (LOL) gene cluster, lolN and lolM, were predicted to encode an N-acetamidase (deacetylase) and a methyltransferase, respectively. A knockout strain lacking both lolN and lolM stopped the biosynthesis at N-acetylnorloline, and complementation with the two wild-type genes restored production of N-formylloline and N-acetylloline. These results indicated that lolN and lolM are required in the steps from N-acetylnorloline to other lolines. The function of LolM as an N-methyltransferase was confirmed by its heterologous expression in yeast resulting in conversion of norloline to loline, and of loline to N-methylloline. One of the more abundant lolines, N-acetylloline, was observed in some but not all plants with symbiotic Epichloë siegelii, and when provided with exogenous loline, asymbiotic meadow fescue (Lolium pratense) plants produced N-acetylloline, suggesting that a plant acetyltransferase catalyzes N-acetylloline formation. We conclude that although most loline alkaloid biosynthesis reactions are catalyzed by fungal enzymes, both fungal and plant enzymes are responsible for the

  7. Enzymes from fungal and plant origin required for chemical diversification of insecticidal loline alkaloids in grass-Epichloë symbiota.

    Directory of Open Access Journals (Sweden)

    Juan Pan

    Full Text Available The lolines are a class of bioprotective alkaloids that are produced by Epichloë species, fungal endophytes of grasses. These alkaloids are saturated 1-aminopyrrolizidines with a C2 to C7 ether bridge, and are structurally differentiated by the various modifications of the 1-amino group: -NH2 (norloline, -NHCH3 (loline, -N(CH32 (N-methylloline, -N(CH3Ac (N-acetylloline, -NHAc (N-acetylnorloline, and -N(CH3CHO (N-formylloline. Other than the LolP cytochrome P450, which is required for conversion of N-methylloline to N-formylloline, the enzymatic steps for loline diversification have not yet been established. Through isotopic labeling, we determined that N-acetylnorloline is the first fully cyclized loline alkaloid, implying that deacetylation, methylation, and acetylation steps are all involved in loline alkaloid diversification. Two genes of the loline alkaloid biosynthesis (LOL gene cluster, lolN and lolM, were predicted to encode an N-acetamidase (deacetylase and a methyltransferase, respectively. A knockout strain lacking both lolN and lolM stopped the biosynthesis at N-acetylnorloline, and complementation with the two wild-type genes restored production of N-formylloline and N-acetylloline. These results indicated that lolN and lolM are required in the steps from N-acetylnorloline to other lolines. The function of LolM as an N-methyltransferase was confirmed by its heterologous expression in yeast resulting in conversion of norloline to loline, and of loline to N-methylloline. One of the more abundant lolines, N-acetylloline, was observed in some but not all plants with symbiotic Epichloë siegelii, and when provided with exogenous loline, asymbiotic meadow fescue (Lolium pratense plants produced N-acetylloline, suggesting that a plant acetyltransferase catalyzes N-acetylloline formation. We conclude that although most loline alkaloid biosynthesis reactions are catalyzed by fungal enzymes, both fungal and plant enzymes are responsible for

  8. Cysteine Biosynthesis Controls Serratia marcescens Phospholipase Activity.

    Science.gov (United States)

    Anderson, Mark T; Mitchell, Lindsay A; Mobley, Harry L T

    2017-08-15

    Serratia marcescens causes health care-associated opportunistic infections that can be difficult to treat due to a high incidence of antibiotic resistance. One of the many secreted proteins of S. marcescens is the PhlA phospholipase enzyme. Genes involved in the production and secretion of PhlA were identified by screening a transposon insertion library for phospholipase-deficient mutants on phosphatidylcholine-containing medium. Mutations were identified in four genes ( cyaA , crp , fliJ , and fliP ) that are involved in the flagellum-dependent PhlA secretion pathway. An additional phospholipase-deficient isolate harbored a transposon insertion in the cysE gene encoding a predicted serine O -acetyltransferase required for cysteine biosynthesis. The cysE requirement for extracellular phospholipase activity was confirmed using a fluorogenic phospholipase substrate. Phospholipase activity was restored to the cysE mutant by the addition of exogenous l-cysteine or O -acetylserine to the culture medium and by genetic complementation. Additionally, phlA transcript levels were decreased 6-fold in bacteria lacking cysE and were restored with added cysteine, indicating a role for cysteine-dependent transcriptional regulation of S. marcescens phospholipase activity. S. marcescens cysE mutants also exhibited a defect in swarming motility that was correlated with reduced levels of flhD and fliA flagellar regulator gene transcription. Together, these findings suggest a model in which cysteine is required for the regulation of both extracellular phospholipase activity and surface motility in S. marcescens IMPORTANCE Serratia marcescens is known to secrete multiple extracellular enzymes, but PhlA is unusual in that this protein is thought to be exported by the flagellar transport apparatus. In this study, we demonstrate that both extracellular phospholipase activity and flagellar function are dependent on the cysteine biosynthesis pathway. Furthermore, a disruption of cysteine

  9. Transplant tourism and invasive fungal infection.

    Science.gov (United States)

    Al Salmi, I; Metry, A M; Al Ismaili, F; Hola, A; Al Riyami, M; Khamis, F; Al-Abri, S

    2018-04-01

    Deceased and live-related renal transplants (RTXs) are approved procedures that are performed widely throughout the world. In certain regions, commercial RTX has become popular, driven by financial greed. This retrospective, descriptive study was performed at the Royal Hospital from 2013 to 2015. Data were collected from the national kidney transplant registry of Oman. All transplant cases retrieved were divided into two groups: live-related RTX performed in Oman and commercial-unrelated RTX performed abroad. These groups were then divided again into those with and without evidence of fungal infection, either in the wound or renal graft. A total of 198 RTX patients were identified, of whom 162 (81.8%) had undergone a commercial RTX that was done abroad. Invasive fungal infections (IFIs) were diagnosed in 8% of patients who had undergone a commercial RTX; of these patients, 76.9% underwent a nephrectomy and 23.1% continued with a functioning graft. None of the patients with RTXs performed at the Royal Hospital contracted an IFI. The most common fungal isolates were Aspergillus species (including Aspergillus flavus, Aspergillus fumigatus, Aspergillus nidulans, and Aspergillus nigricans), followed by Zygomycetes. However, there was no evidence of fungal infection including Aspergillus outside the graft site. Computed tomography (CT) findings showed infarction of the graft, renal artery thrombosis, aneurysmal dilatation of the external iliac artery, fungal ball, or just the presence of a perigraft collection. Of the total patients with IFIs, 23.1% died due to septic shock and 53.8% were alive and on hemodialysis. The remaining 23.1% who did not undergo nephrectomy demonstrated acceptable graft function. This is the largest single-center study on commercial RTX reporting the highest number of patients with IFI acquired over a relatively short period of time. Aspergillus spp were the main culprit fungi, with no Candida spp being isolated. A high index of suspicion might

  10. Fungal Urinary Tract Infection in Burn Patients‎

    Directory of Open Access Journals (Sweden)

    Suad Yousuf Aldorkee

    2017-11-01

    Full Text Available Background: Urinary tract infection is the most common hospital-acquired infection. Fungal species are unusual causes of urinary tract infection in healthy individuals, but common in the hospital setting or among patients with predisposing diseases and structural abnormalities of the kidney and collecting system. Burn patients are susceptible to nosocomial infections owing to the immunocompromising effects of burn injury, cutaneous and respiratory tract injury, prolonged intensive care unit stays and broad-spectrum antibiotic therapy. Objective: The study population includes adult patients of both genders who presented with different percentages of body burns. Urine sample was collected from each patient at the time of admission and weekly thereafter for 6 weeks and sent for general urine examination and urine culture to test for the possibility of fungal growth. Those who found to develop fungal UTI by urine culture during their hospitalization and had no infection at the time of admission were selected as subjects for our study. Results: 28 (18.6% patients had positive fungal culture during their hospitalization, 11 of them were males and 17 were females, the most common age of presentation was 41-50 years and the mean age ± SD was (44.4 ± 10.7 years. The most common isolated fungi were Candida albicans (64.3%, followed by Candida glabrata (21.4% and Candida tropicalis (7.1%. The majority of patients developed infection within the 2nd and 3rd weeks of hospitalization, however, those who presented with total body surface area burned > 40% developed an earlier infection within the 1st week. Female gender, urethral catheterization and diabetes mellitus were significantly associated with higher risk of infection as the P values were 0.03, 0.005 and 0.004 respectively. Conclusion: Fungal urinary tract infection occurred in 18.6% of burn patients. The most common causative fungi are candida species. Advanced age, female gender, high percentage of

  11. Penicillin production in industrial strain Penicillium chrysogenum P2niaD18 is not dependent on the copy number of biosynthesis genes.

    Science.gov (United States)

    Ziemons, Sandra; Koutsantas, Katerina; Becker, Kordula; Dahlmann, Tim; Kück, Ulrich

    2017-02-16

    Multi-copy gene integration into microbial genomes is a conventional tool for obtaining improved gene expression. For Penicillium chrysogenum, the fungal producer of the beta-lactam antibiotic penicillin, many production strains carry multiple copies of the penicillin biosynthesis gene cluster. This discovery led to the generally accepted view that high penicillin titers are the result of multiple copies of penicillin genes. Here we investigated strain P2niaD18, a production line that carries only two copies of the penicillin gene cluster. We performed pulsed-field gel electrophoresis (PFGE), quantitative qRT-PCR, and penicillin bioassays to investigate production, deletion and overexpression strains generated in the P. chrysogenum P2niaD18 background, in order to determine the copy number of the penicillin biosynthesis gene cluster, and study the expression of one penicillin biosynthesis gene, and the penicillin titer. Analysis of production and recombinant strain showed that the enhanced penicillin titer did not depend on the copy number of the penicillin gene cluster. Our assumption was strengthened by results with a penicillin null strain lacking pcbC encoding isopenicillin N synthase. Reintroduction of one or two copies of the cluster into the pcbC deletion strain restored transcriptional high expression of the pcbC gene, but recombinant strains showed no significantly different penicillin titer compared to parental strains. Here we present a molecular genetic analysis of production and recombinant strains in the P2niaD18 background carrying different copy numbers of the penicillin biosynthesis gene cluster. Our analysis shows that the enhanced penicillin titer does not strictly depend on the copy number of the cluster. Based on these overall findings, we hypothesize that instead, complex regulatory mechanisms are prominently implicated in increased penicillin biosynthesis in production strains.

  12. Biosynthesis of dipicolinic acid in Clostridium roseum

    Energy Technology Data Exchange (ETDEWEB)

    Prakasan, K. (Paraiba Univ., Joao Pessoa (Brazil)); Sharma, D. (Gobind Ballabh Pant Univ. of Agriculture and Technology, Nainital (India))

    1981-02-01

    Dipicolinic acid (DPA) synthesis was studied in Clostridium roseum by permitting the organism to complete vegetative growth in trypticase medium and trasfering the cells to a non-growth-promoting-medium, supplemented with the appropriate /sup 14/C-labelled precursors to complete sporulation and assaying the incorporation of label into DPA. Glu, asp, ala, ser and acetate were found to be efficient precursors of DPA and each one influenced the incorporation of other into DPA. The data suggest that a C/sub 5/ precursor is being trasformed into a C/sub 4/ intermediate, and a C/sub 2/ precursor into a C/sub 4/ intermediate, before their entry into DPA carbon structure. A C/sub 4/ plus C/sub 3/ condensation is favoured over C/sub 5/ plus C/sub 2/ or other condensation in the DPA biosynthesis.

  13. Polyamine biosynthesis during germination of yeast ascospores.

    Science.gov (United States)

    Brawley, J V; Ferro, A J

    1979-01-01

    The role of the diamine putrescine during germination and outgrowth of ascospores of Saccharomyces cerevisiae was examined. Ornithine decarboxylase activity increased and declined rapidly during germination and outgrowth; peak activity was attained after the cells had proceeded through the G1 interval of the cell cycle, whereas minimal activity was present at the completion of the first cell division. alpha-Methylornithine inhibited both ornithine decarboxylase activity and the in vivo accumulation of putrescine. In the presence of alpha-methylornithireak dormancy and proceed through one cell division. Subsequent cellular growth, however, was retarded but not completely inhibited. The supplementation of Methylglyoxal bis(guanylhydrazone) to sporulation medium greatly inhibited this sexual process. These data suggest that the synthesis of putrescine is not required for the breaking of spore dormancy, but that polyamine biosynthesis may be essential for meiosis and sporulation. PMID:387744

  14. Biosurfactant Mediated Biosynthesis of Selected Metallic Nanoparticles

    Science.gov (United States)

    Płaza, Grażyna A.; Chojniak, Joanna; Banat, Ibrahim M.

    2014-01-01

    Developing a reliable experimental protocol for the synthesis of nanomaterials is one of the challenging topics in current nanotechnology particularly in the context of the recent drive to promote green technologies in their synthesis. The increasing need to develop clean, nontoxic and environmentally safe production processes for nanoparticles to reduce environmental impact, minimize waste and increase energy efficiency has become essential in this field. Consequently, recent studies on the use of microorganisms in the synthesis of selected nanoparticles are gaining increased interest as they represent an exciting area of research with considerable development potential. Microorganisms are known to be capable of synthesizing inorganic molecules that are deposited either intra- or extracellularly. This review presents a brief overview of current research on the use of biosurfactants in the biosynthesis of selected metallic nanoparticles and their potential importance. PMID:25110864

  15. Terpenoids and Their Biosynthesis in Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Bagmi Pattanaik

    2015-01-01

    Full Text Available Terpenoids, or isoprenoids, are a family of compounds with great structural diversity which are essential for all living organisms. In cyanobacteria, they are synthesized from the methylerythritol-phosphate (MEP pathway, using glyceraldehyde 3-phosphate and pyruvate produced by photosynthesis as substrates. The products of the MEP pathway are the isomeric five-carbon compounds isopentenyl diphosphate and dimethylallyl diphosphate, which in turn form the basic building blocks for formation of all terpenoids. Many terpenoid compounds have useful properties and are of interest in the fields of pharmaceuticals and nutrition, and even potentially as future biofuels. The MEP pathway, its function and regulation, and the subsequent formation of terpenoids have not been fully elucidated in cyanobacteria, despite its relevance for biotechnological applications. In this review, we summarize the present knowledge about cyanobacterial terpenoid biosynthesis, both regarding the native metabolism and regarding metabolic engineering of cyanobacteria for heterologous production of non-native terpenoids.

  16. Terpenoids and Their Biosynthesis in Cyanobacteria

    Science.gov (United States)

    Pattanaik, Bagmi; Lindberg, Pia

    2015-01-01

    Terpenoids, or isoprenoids, are a family of compounds with great structural diversity which are essential for all living organisms. In cyanobacteria, they are synthesized from the methylerythritol-phosphate (MEP) pathway, using glyceraldehyde 3-phosphate and pyruvate produced by photosynthesis as substrates. The products of the MEP pathway are the isomeric five-carbon compounds isopentenyl diphosphate and dimethylallyl diphosphate, which in turn form the basic building blocks for formation of all terpenoids. Many terpenoid compounds have useful properties and are of interest in the fields of pharmaceuticals and nutrition, and even potentially as future biofuels. The MEP pathway, its function and regulation, and the subsequent formation of terpenoids have not been fully elucidated in cyanobacteria, despite its relevance for biotechnological applications. In this review, we summarize the present knowledge about cyanobacterial terpenoid biosynthesis, both regarding the native metabolism and regarding metabolic engineering of cyanobacteria for heterologous production of non-native terpenoids. PMID:25615610

  17. Biosurfactant Mediated Biosynthesis of Selected Metallic Nanoparticles

    Directory of Open Access Journals (Sweden)

    Grażyna A. Płaza

    2014-08-01

    Full Text Available Developing a reliable experimental protocol for the synthesis of nanomaterials is one of the challenging topics in current nanotechnology particularly in the context of the recent drive to promote green technologies in their synthesis. The increasing need to develop clean, nontoxic and environmentally safe production processes for nanoparticles to reduce environmental impact, minimize waste and increase energy efficiency has become essential in this field. Consequently, recent studies on the use of microorganisms in the synthesis of selected nanoparticles are gaining increased interest as they represent an exciting area of research with considerable development potential. Microorganisms are known to be capable of synthesizing inorganic molecules that are deposited either intra- or extracellularly. This review presents a brief overview of current research on the use of biosurfactants in the biosynthesis of selected metallic nanoparticles and their potential importance.

  18. Biosynthesis of dipicolinic acid in Clostridium roseum

    International Nuclear Information System (INIS)

    Prakasan, K.; Sharma, D.

    1981-01-01

    Dipicolinic acid (DPA) synthesis was studied in Clostridium roseum by permitting the organism to complete vegetative growth in trypticase medium and trasfering the cells to a non-growth-promoting-medium, supplemented with the appropriate 14 C-labelled precursors to complete sporulation and assaying the incorporation of label into DPA. Glu, asp, ala, ser and acetate were found to be efficient precursors of DPA and each one influenced the incorporation of other into DPA. The data suggest that a C 5 precursor is being trasformed into a C 4 intermediate, and a C 2 precursor into a C 4 intermediate, before their entry into DPA carbon structure. A C 4 plus C 3 condensation is favoured over C 5 plus C 2 or other condensation in the DPA biosynthesis. (Author) [pt

  19. Biosynthesis and function of plant lipids

    International Nuclear Information System (INIS)

    Thomson, W.W.; Mudd, J.B.; Gibbs, M.

    1983-01-01

    The Sixth Annual Symposium in Botany and Plant Physiology was held January 13-15, 1983, at the University of California, Riverside. This volume comprises the papers that were presented. Subjects discussed at the symposium covered a wide range in the field of plant lipids. Biosynthesis of lipids occupied an important fraction of the presentations at the symposium. Subjects included detailed studies of the enzymes of fatty acid synthesis, several discussions of the incorporation of fatty acids into glycerolipids and the further modification of the fatty acids, and the synthesis of glycerolipids and desaturation of fatty acids in both maturing oilseeds and chloroplasts. The physicochemical studies of glycerolipids and sterols in artificial membranes have led to distinct conclusions about their behaviour which must be relevant in the biological membrane. Results on the functional consequences of modifying the galactolipid composition in the chloroplast were an encouraging sign of progress in the attempts to relate membrane lipid composition to physiological function

  20. A Molecular Description of Cellulose Biosynthesis

    Science.gov (United States)

    McNamara, Joshua T.; Morgan, Jacob L.W.; Zimmer, Jochen

    2016-01-01

    Cellulose is the most abundant biopolymer on Earth, and certain organisms from bacteria to plants and animals synthesize cellulose as an extracellular polymer for various biological functions. Humans have used cellulose for millennia as a material and an energy source, and the advent of a lignocellulosic fuel industry will elevate it to the primary carbon source for the burgeoning renewable energy sector. Despite the biological and societal importance of cellulose, the molecular mechanism by which it is synthesized is now only beginning to emerge. On the basis of recent advances in structural and molecular biology on bacterial cellulose synthases, we review emerging concepts of how the enzymes polymerize glucose molecules, how the nascent polymer is transported across the plasma membrane, and how bacterial cellulose biosynthesis is regulated during biofilm formation. Additionally, we review evolutionary commonalities and differences between cellulose synthases that modulate the nature of the cellulose product formed. PMID:26034894

  1. Phenylpropenes: Occurrence, Distribution, and Biosynthesis in Fruit.

    Science.gov (United States)

    Atkinson, Ross G

    2018-03-14

    Phenylpropenes such as eugenol, chavicol, estragole, and anethole contribute to the flavor and aroma of a number of important herbs and spices. They have been shown to function as floral attractants for pollinators and to have antifungal and antimicrobial activities. Phenylpropenes are also detected as free volatiles and sequestered glycosides in a range of economically important fresh fruit species including apple, strawberry, tomato, and grape. Although they contribute a relatively small percentage of total volatiles compared with esters, aldehydes, and alcohols, phenylpropenes have been shown to contribute spicy anise- and clove-like notes to fruit. Phenylpropenes are typically found in fruit throughout development and to reach maximum concentrations in ripe fruit. Genes involved in the biosynthesis of phenylpropenes have been characterized and manipulated in strawberry and apple, which has validated the importance of these compounds to fruit aroma and may help elucidate other functions for phenylpropenes in fruit.

  2. Collagens--structure, function, and biosynthesis.

    Science.gov (United States)

    Gelse, K; Pöschl, E; Aigner, T

    2003-11-28

    The extracellular matrix represents a complex alloy of variable members of diverse protein families defining structural integrity and various physiological functions. The most abundant family is the collagens with more than 20 different collagen types identified so far. Collagens are centrally involved in the formation of fibrillar and microfibrillar networks of the extracellular matrix, basement membranes as well as other structures of the extracellular matrix. This review focuses on the distribution and function of various collagen types in different tissues. It introduces their basic structural subunits and points out major steps in the biosynthesis and supramolecular processing of fibrillar collagens as prototypical members of this protein family. A final outlook indicates the importance of different collagen types not only for the understanding of collagen-related diseases, but also as a basis for the therapeutical use of members of this protein family discussed in other chapters of this issue.

  3. Biosynthesis of archaeal membrane ether lipids

    Directory of Open Access Journals (Sweden)

    Samta eJain

    2014-11-01

    Full Text Available A vital function of the cell membrane in all living organism is to maintain the membrane permeability barrier and fluidity. The composition of the phospholipid bilayer is distinct in archaea when compared to bacteria and eukarya. In archaea, isoprenoid hydrocarbon side chains are linked via an ether bond to the sn-glycerol-1-phosphate backbone. In bacteria and eukarya on the other hand, fatty acid side chains are linked via an ester bond to the sn-glycerol-3-phosphate backbone. The polar head groups are globally shared in the three domains of life. The unique membrane lipids of archaea have been implicated not only in the survival and adaptation of the organisms to extreme environments but also to form the basis of the membrane composition of the last universal common ancestor (LUCA. In nature, a diverse range of archaeal lipids is found, the most common are the diether (or archaeol and the tetraether (or caldarchaeol lipids that form a monolayer. Variations in chain length, cyclization and other modifications lead to diversification of these lipids. The biosynthesis of these lipids is not yet well understood however progress in the last decade has led to a comprehensive understanding of the biosynthesis of archaeol. This review describes the current knowledge of the biosynthetic pathway of archaeal ether lipids; insights on the stability and robustness of archaeal lipid membranes; and evolutionary aspects of the lipid divide and the last universal common ancestor LUCA. It examines recent advances made in the field of pathway reconstruction in bacteria.

  4. In vitro biosynthesis of complement protein D

    International Nuclear Information System (INIS)

    Barnum, S.R.

    1985-01-01

    The aim of this study was twofold: to determine site(s) of complement protein D biosynthesis and to examine D biosynthesis with respect to the kinetics of D secretion, the post-translational modification of D and the tissue-specific differences in D secretion and processing. Antigenic D was detected in the culture supernatants of two cell lines, U937 and HepG2, and adherent blood monocytes by a solid-phase radioimmunoassay. D secreted by U937 cells was hemolytically active with a specific activity comparable to D in serum. De novo synthesis of D by U937 cells was demonstrated with the use of cycloheximide. Biosynthetic labeling using 35 S labeled methionine or cysteine, followed by immunoprecipitation demonstrated a single d band intra- and extra-cellularly in all three cell types as analyzed by SDS-PAGE and auto-radiography. Elevated serum D levels in individuals with IgA nephropathy led to studies on the D levels in serum and urine of individuals with chronic renal failure and an individual with Fanconi's syndrome. The former group had elevated serum D levels, compared to normals, and insignificant levels of D in their urine while the patient with Fanconi's syndrome had normal serum D levels but markedly elevated urinary D levels. These studies demonstrate that the monocyte and hepatocyte are both sites of D synthesis and that there are no apparent differences in the secretion rates and processing of D produced by these cell types. The results also suggest that D is not synthesized or secreted as a precursor molecule. Additionally, these studies suggest that the kidney is a major site of D catabolism

  5. Biosynthesis of components with antifungal activity against Aspergillus spp. using Streptomyces hygroscopicus

    Directory of Open Access Journals (Sweden)

    Dodić Jelena M.

    2015-01-01

    Full Text Available Losses of apple fruit during storage are mainly caused by fungal phytopathogens. Traditionally, postharvest fungal disease is controlled by the application of synthetic fungicides. However, the harmful impact on environment as well as human health largely limits their application. To reduce these problems in agrochemicals usage, new compounds for plant protection, which are eco-friendly, should be developed. The aim of this study is optimization of medium composition in terms of glucose, soybean meal and phosphates content, by applying response surface methodology, for the production of agents with antifungal activity against Aspergillus spp. For biosynthesis was used strain of Streptomyces hygroscopicus isolated from the environment. Experiments were carried out in accordance with Box-Behnken design with three factors on three levels and three repetitions in the central point. Antifungal activity of the obtained cultivation mediums against Aspergillus oryzae and Aspergillus niger was determined, in vitro, using the diffusion - disc method. For determination optimal medium components desirability function was used. Achieved model predicts that the maximum inhibition zone diameter (40.93 mm against test microorganisms is produced when the initial content of glucose, soybean meal and phosphates are 47.77 g/l, 24.54 g/l and 0.98 g/l, respectively. To minimize the consumption of medium components and costs of effluents processing, additional three sets of optimization were made. The chosen method for optimization of medium components was efficient, relatively simple and time and material saving. Obtained results can be used for the further techno-economic analysis of the process to select optimal medium composition for industrial application.

  6. Causal agents of Fusarium head blight of durum wheat (Triticum durum Desf.) in central Italy and their in vitro biosynthesis of secondary metabolites.

    Science.gov (United States)

    Beccari, G; Colasante, V; Tini, F; Senatore, M T; Prodi, A; Sulyok, M; Covarelli, L

    2018-04-01

    Durum wheat samples harvested in central Italy (Umbria) were analyzed to: evaluate the occurrence of the fungal community in the grains, molecularly identify the Fusarium spp. which are part of the Fusarium head blight (FHB) complex and characterize the in vitro secondary metabolite profiles of a subset of Fusarium strains. The Fusarium genus was one of the main components of the durum wheat fungal community. The FHB complex was composed of eight species: Fusarium avenaceum (61%), F. graminearum (22%), F. poae (9%), F. culmorum (4%), F. proliferatum (2%), F. sporotrichioides (1%), F. sambucinum (0.5%) and F. langsethiae (0.5%). F. graminearum population was mainly composed of the 15-acetyldeoxynivalenol chemotype, while, F. culmorum population was composed of the 3-acetyldeoxynivalenol chemotype. In vitro characterization of secondary metabolite biosynthesis was conducted for a wide spectrum of substances, showing the mycotoxigenic potential of the species complex. F. avenaceum strains were characterized by high enniantin and moniliformin production. F. graminearum strains were in prevalence deoxynivalenol producers. F. poae strains were characterized by a high biosynthesis of beauvericin like the F. sporotrichioides strain which was also found to be a high T-2/HT-2 toxins producer. Production of aurofusarin, butenolide, gibepyrone D, fusarin C, apicidin was also reported for the analyzed strains. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Sensitization to fungal allergens: Resolved and unresolved issues

    Directory of Open Access Journals (Sweden)

    Yuma Fukutomi

    2015-10-01

    Despite its importance in the management of allergic diseases, precise recognition of species-specific IgE sensitization to fungal allergens is often challenging because the majority of fungal extracts exhibit broad cross-reactivity with taxonomically unrelated fungi. Recent progress in gene technology has contributed to the identification of specific and cross-reactive allergen components from different fungal sources. However, data demonstrating the clinical relevance of IgE reactivity to these allergen components are still insufficient.

  8. Lipid Biosynthesis as an Antifungal Target

    Directory of Open Access Journals (Sweden)

    Jiao Pan

    2018-04-01

    Full Text Available Lipids, commonly including phospholipids, sphingolipids, fatty acids, sterols, and triacylglycerols (TAGs, are important biomolecules for the viability of all cells. Phospholipids, sphingolipids, and sterols are important constituents of biological membranes. Many lipids play important roles in the regulation of cell metabolism by acting as signaling molecules. Neutral lipids, including TAGs and sterol esters (STEs, are important storage lipids in cells. In view of the importance of lipid molecules, this review briefly summarizes the metabolic pathways for sterols, phospholipids, sphingolipids, fatty acids, and neutral lipids in fungi and illustrates the differences between fungal and human (or other mammalian cells, especially in relation to lipid biosynthetic pathways. These differences might provide valuable clues for us to find target proteins for novel antifungal drugs. In addition, the development of lipidomics technology in recent years has supplied us with a shortcut for finding new antifungal drug targets; this ability is important for guiding our research on pathogenic fungi.

  9. PLANT VOLATILES. Biosynthesis of monoterpene scent compounds in roses.

    Science.gov (United States)

    Magnard, Jean-Louis; Roccia, Aymeric; Caissard, Jean-Claude; Vergne, Philippe; Sun, Pulu; Hecquet, Romain; Dubois, Annick; Hibrand-Saint Oyant, Laurence; Jullien, Frédéric; Nicolè, Florence; Raymond, Olivier; Huguet, Stéphanie; Baltenweck, Raymonde; Meyer, Sophie; Claudel, Patricia; Jeauffre, Julien; Rohmer, Michel; Foucher, Fabrice; Hugueney, Philippe; Bendahmane, Mohammed; Baudino, Sylvie

    2015-07-03

    The scent of roses (Rosa x hybrida) is composed of hundreds of volatile molecules. Monoterpenes represent up to 70% percent of the scent content in some cultivars, such as the Papa Meilland rose. Monoterpene biosynthesis in plants relies on plastid-localized terpene synthases. Combining transcriptomic and genetic approaches, we show that the Nudix hydrolase RhNUDX1, localized in the cytoplasm, is part of a pathway for the biosynthesis of free monoterpene alcohols that contribute to fragrance in roses. The RhNUDX1 protein shows geranyl diphosphate diphosphohydrolase activity in vitro and supports geraniol biosynthesis in planta. Copyright © 2015, American Association for the Advancement of Science.

  10. Autoreactive T Cells and Chronic Fungal Infection Drive Esophageal Carcinogenesis

    Science.gov (United States)

    Zhu, Feng; Willette-Brown, Jami; Song, Na-Young; Lomada, Dakshayani; Song, Yongmei; Xue, Liyan; Gray, Zane; Zhao, Zitong; Davis, Sean R.; Sun, Zhonghe; Zhang, Peilin; Wu, Xiaolin; Zhan, Qimin; Richie, Ellen R.; Hu, Yinling

    2018-01-01

    SUMMARY Humans with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), a T cell–driven autoimmune disease caused by impaired central tolerance, are susceptible to developing chronic fungal infection and esophageal squamous cell carcinoma (ESCC). However, the relationship between autoreactive T cells and chronic fungal infection in ESCC development remains unclear. We find that kinase-dead Ikkα knockin mice develop phenotypes reminiscent of APECED, including impaired central tolerance, autoreactive T cells, chronic fungal infection, and ESCCs expressing specific human ESCC markers. Using this model, we investigated the potential link between ESCC and fungal infection. Autoreactive CD4 T cells permit fungal infection and incite tissue injury and inflammation. Antifungal treatment or depletion of autoreactive CD4 T cells rescues, whereas oral fungal administration promotes, ESCC development. Inhibition of inflammation or EGFR activity decreases fungal burden. Importantly, fungal infection is highly associated with ESCCs in non-autoimmune human patients. Therefore, autoreactive T cells and chronic fungal infection, fostered by inflammation and epithelial injury, promote ESCC development. PMID:28407484

  11. Natural occurrence of fungi and fungal metabolites in moldy tomatoes

    DEFF Research Database (Denmark)

    Andersen, B.; Frisvad, Jens Christian

    2004-01-01

    Fresh tomatoes, homegrown and from supermarkets, with developing fungal lesions were collected. Each lesion was sampled, and the resulting fungal cultures were identified morphologically, and extracted for analyzes of secondary metabolites. The tomatoes were incubated at 25 degreesC for a week....... extracted, and analyzed for fungal metabolites. Extracts from pure cultures were compared with extracts from the moldy tomatoes and fungal metabolite standards in two HPLC systems with DAD and FLD detection. The results showed that Penicillium tularense, Stemphylium eturmiunum. and S. cf. lycopersici were...

  12. Fungal cell gigantism during mammalian infection.

    Directory of Open Access Journals (Sweden)

    Oscar Zaragoza

    2010-06-01

    Full Text Available The interaction between fungal pathogens with the host frequently results in morphological changes, such as hyphae formation. The encapsulated pathogenic fungus Cryptococcus neoformans is not considered a dimorphic fungus, and is predominantly found in host tissues as round yeast cells. However, there is a specific morphological change associated with cryptococcal infection that involves an increase in capsule volume. We now report another morphological change whereby gigantic cells are formed in tissue. The paper reports the phenotypic characterization of giant cells isolated from infected mice and the cellular changes associated with giant cell formation. C. neoformans infection in mice resulted in the appearance of giant cells with cell bodies up to 30 microm in diameter and capsules resistant to stripping with gamma-radiation and organic solvents. The proportion of giant cells ranged from 10 to 80% of the total lung fungal burden, depending on infection time, individual mice, and correlated with the type of immune response. When placed on agar, giant cells budded to produce small daughter cells that traversed the capsule of the mother cell at the speed of 20-50 m/h. Giant cells with dimensions that approximated those in vivo were observed in vitro after prolonged culture in minimal media, and were the oldest in the culture, suggesting that giant cell formation is an aging-dependent phenomenon. Giant cells recovered from mice displayed polyploidy, suggesting a mechanism by which gigantism results from cell cycle progression without cell fission. Giant cell formation was dependent on cAMP, but not on Ras1. Real-time imaging showed that giant cells were engaged, but not engulfed by phagocytic cells. We describe a remarkable new strategy for C. neoformans to evade the immune response by enlarging cell size, and suggest that gigantism results from replication without fission, a phenomenon that may also occur with other fungal pathogens.

  13. Complications of hematopoietic stem transplantation: Fungal infections.

    Science.gov (United States)

    Omrani, Ali S; Almaghrabi, Reem S

    2017-12-01

    Patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT) are at increased risk of invasive fungal infections, especially during the early neutropenic phase and severe graft-versus-host disease. Mold-active prophylaxis should be limited to the highest risk groups. Empiric antifungal therapy for HSCT with persistent febrile neutropenia is associated with unacceptable response rates, unnecessary antifungal therapy, increased risk of toxicity, and inflated costs. Empiric therapy should not be a substitute for detailed work up to identify the cause of fever in such patients. The improved diagnostic performance of serum biomarkers such as galactomannan and β-D-glucan, as well as polymerase chain reaction assays has allowed the development of diagnostic-driven antifungal therapy strategies for high risk patients. Diagnostic-driven approaches have resulted in reduced unnecessary antifungal exposure, improved diagnosis of invasive fungal disease, and reduced costs without increased risk of mortality. The appropriateness of diagnostic-driven antifungal strategy for individual HSCT centers depends on the availability and turnaround times for diagnostics, multidisciplinary expertise, and the local epidemiology of invasive fungal infections. Echinocandins are the treatment of choice for invasive candidiasis in most HSCT recipients. Fluconazole may be used for the treatment of invasive candidiasis in hemodynamically stable patients with no prior azole exposure. The primary treatment of choice for invasive aspergillosis is voriconazole. Alternatives include isavuconazole and lipid formulations of amphotericin. Currently available evidence does not support routine primary combination antifungal therapy for invasive aspergillosis. However, combination salvage antifungal therapy may be considered in selected patients. Therapeutic drug monitoring is recommended for the majority of HSCT recipients on itraconazole, posaconazole, or voriconazole. Copyright © 2017

  14. Optic neuropathy due to allergic fungal rhinosinusitis

    Directory of Open Access Journals (Sweden)

    Jiji Tresa Cyriac

    2011-01-01

    Full Text Available An uncommon case of allergic fungal rhinosinusitis presented to the ophthalmology outpatient department of our hospital with complaints of blurred vision in the right eye of a few days duration and vague complaints of pain around the eyes. The visual acuity on examination was grossly reduced in the right eye and normal in the left eye. Color vision was normal. Anterior segment examination including pupils was normal. Dilated fundus examination was normal except for temporal pallor in the right optic disc. Automated perimetry and magnetic resonance imaging (MRI scan of brain and orbit were done. The imaging report showed a bilateral pansinusitis with pressure on the right optic nerve. Perimetry showed a superior field defect on the right side. ENT consultation and computed tomography (CT with contrast helped to diagnose this as a case of allergic fungal rhinosinusitis. The patient was started on systemic steroids under the care of the ENT surgeon. After a few days, pre-operative assessment showed a gross improvement of visual acuity. Endoscopic sinus surgery was done to remove the polyps and thick mucus material. Histopathologic examination confirmed allergic fungal mucin. Days after surgery, the visual acuity improved further and repeat perimetry showed gross improvement in the visual field. Good history taking and a detailed ophthalmic examination, keeping in mind the probable causes of loss of vision of few days duration with no findings other than a decreased visual acuity and a suspicious disc, were key to the early diagnosis and investigation in this case. This helped in early referral and management of the case before permanent damage and irreversible visual loss occurred. The optic nerve is a cranial nerve which, once damaged permanently, will not regenerate. The amount of sinus involvement was extensive on both sides and invariably the left optic nerve would have been involved in a few days, if intervention was delayed.

  15. Fungal cell gigantism during mammalian infection.

    Science.gov (United States)

    Zaragoza, Oscar; García-Rodas, Rocío; Nosanchuk, Joshua D; Cuenca-Estrella, Manuel; Rodríguez-Tudela, Juan Luis; Casadevall, Arturo

    2010-06-17

    The interaction between fungal pathogens with the host frequently results in morphological changes, such as hyphae formation. The encapsulated pathogenic fungus Cryptococcus neoformans is not considered a dimorphic fungus, and is predominantly found in host tissues as round yeast cells. However, there is a specific morphological change associated with cryptococcal infection that involves an increase in capsule volume. We now report another morphological change whereby gigantic cells are formed in tissue. The paper reports the phenotypic characterization of giant cells isolated from infected mice and the cellular changes associated with giant cell formation. C. neoformans infection in mice resulted in the appearance of giant cells with cell bodies up to 30 microm in diameter and capsules resistant to stripping with gamma-radiation and organic solvents. The proportion of giant cells ranged from 10 to 80% of the total lung fungal burden, depending on infection time, individual mice, and correlated with the type of immune response. When placed on agar, giant cells budded to produce small daughter cells that traversed the capsule of the mother cell at the speed of 20-50 m/h. Giant cells with dimensions that approximated those in vivo were observed in vitro after prolonged culture in minimal media, and were the oldest in the culture, suggesting that giant cell formation is an aging-dependent phenomenon. Giant cells recovered from mice displayed polyploidy, suggesting a mechanism by which gigantism results from cell cycle progression without cell fission. Giant cell formation was dependent on cAMP, but not on Ras1. Real-time imaging showed that giant cells were engaged, but not engulfed by phagocytic cells. We describe a remarkable new strategy for C. neoformans to evade the immune response by enlarging cell size, and suggest that gigantism results from replication without fission, a phenomenon that may also occur with other fungal pathogens.

  16. Nuclear magnetic resonance (NMR) studies on the biosynthesis of fusaric acid from Fusarium oxysporum f. sp. vasinfectum.

    Science.gov (United States)

    Stipanovic, Robert D; Wheeler, Michael H; Puckhaber, Lorraine S; Liu, Jinggao; Bell, Alois A; Williams, Howard J

    2011-05-25

    Fusarium oxysporum is a fungal pathogen that attacks many important plants. Uniquely pathogenic strains of F. oxysporum f. sp. vasinfectum were inadvertently imported into the United States on live cottonseed for dairy cattle feed. These strains produce exceptionally high concentrations of the phytotoxin fusaric acid. Thus, fusaric acid may be a critical component in the pathogenicity of these biotypes. This study investigated the biosynthesis of fusaric acid using (13)C-labeled substrates including [1,2-(13)C(2)]acetate as well as (13)C- and (15)N-labeled aspartate and [(15)N]glutamine. The incorporation of labeled substrates is consistent with the biosynthesis of fusaric acid from three acetate units at C5-C6, C7-C8, and C9-C10, with the remaining carbons being derived from aspartate via oxaloacetate and the TCA cycle; the oxaloacetate originates in part by transamination of aspartate, but most of the oxaloacetate is derived by deamination of aspartate to fumarate by aspartase. The nitrogen from glutamine is more readily incorporated into fusaric acid than that from aspartate.

  17. Fungal infections of the mucous membrane.

    Science.gov (United States)

    Marques, Silvio Alencar

    2010-01-01

    A clinical review of three potentially severe fungal diseases, which are characterized in many cases by mucosal involvement, is presented. They are paracoccidioidomycosis, histoplasmosis, and mucormycosis. Mucosal involvement for paracoccidioidomycosis and rhinocerebral mucormycosis is frequent. Thus, oral involvement may provide early clue for diagnosis. In paracoccidioidomycosis, the mucosal lesion classically shows superficial ulcers with granular appearance and hemorrhagic points, usually on lips, palate, and jugal mucosa. In mucormycosis, necrosis of the palate followed for purulent discharge is a hallmark of rhinocerebral disease. Treatment with amphotericin B desoxycholate or the new second-generation triazoles is highly efficacious.

  18. Bacterial and fungal markers in tobacco smoke

    International Nuclear Information System (INIS)

    Szponar, B.; Pehrson, C.; Larsson, L.

    2012-01-01

    Previous research has demonstrated that cigarette smoke contains bacterial and fungal components including lipopolysaccharide (LPS) and ergosterol. In the present study we used gas chromatography–mass spectrometry to analyze tobacco as well as mainstream and second hand smoke for 3-hydroxy fatty acids (3-OH FAs) of 10 to 18 carbon chain lengths, used as LPS markers, and ergosterol, used as a marker of fungal biomass. The air concentrations of LPS were 0.0017 nmol/m 3 (N = 5) and 0.0007/m 3 (N = 6) in the smoking vs. non-smoking rooms (p = 0.0559) of the studied private houses, and 0.0231 nmol/m 3 (N = 5) vs. 0.0006 nmol/m 3 (N = 5) (p = 0.0173), respectively, at the worksite. The air concentrations of ergosterol were also significantly higher in rooms with ongoing smoking than in rooms without smoking. A positive correlation was found between LPS and ergosterol in rooms with smoking but not in rooms without smoking. 3-OH C14:0 was the main 3-OH FA, followed by 3-OH C12:0, both in mainstream and second hand smoke and in phenol:water smoke extracts prepared in order to purify the LPS. The Limulus activity of the phenolic phase of tobacco was 3900 endotoxin units (EU)/cigarette; the corresponding amount of the smoke, collected on filters from 8 puffs, was 4 EU/cigarette. Tobacco smoking has been associated with a range of inflammatory airway conditions including COPD, asthma, bronchitis, alveolar hypersensitivity etc. Significant levels of LPS and ergosterol were identified in tobacco smoke and these observations support the hypothesis that microbial components of tobacco smoke contribute to inflammation and airway disease. -- Highlights: ► Air concentration of bacterial and fungal markers is significantly higher in rooms with ongoing smoking than without smoking. ► Bacterial LPS correlates with fungal marker in rooms with ongoing smoking but not without smoking. ► LPS from mainstream smoke contains 3-hydroxy 14:0 and 12:0 fatty acids in similar proportion as

  19. Fungal Fourniers Gangrene in an Immunocompromised Patient

    Directory of Open Access Journals (Sweden)

    Winston Crowell

    2016-01-01

    Full Text Available Fournier's Gangrene is a rapidly progressive necrotizing fasciitis of the groin, perianal and perineal region that is often polymicrobial in nature, often averaging 3 species of bacteria per patient. The typical infection can be due to a host of microbes, including gram positive, gram negative and anaerobic species including. Many of the causative organisms are found in the normal microbial flora of the perineum. Therefore, Fourniers is an opportunistic infection most commonly affecting the immunosuppressed. The majority of Fournier's gangrene are bacterial; however there have been cases of fungal Fournier's gangrene reported in the literature.

  20. Bacterial and fungal markers in tobacco smoke

    Energy Technology Data Exchange (ETDEWEB)

    Szponar, B., E-mail: szponar@iitd.pan.wroc.pl [Lund University, Dept. of Laboratory Medicine, Soelvegatan 23, 223 62 Lund (Sweden); Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Rudolfa Weigla 12, 53-114 Wroclaw (Poland); Pehrson, C.; Larsson, L. [Lund University, Dept. of Laboratory Medicine, Soelvegatan 23, 223 62 Lund (Sweden)

    2012-11-01

    Previous research has demonstrated that cigarette smoke contains bacterial and fungal components including lipopolysaccharide (LPS) and ergosterol. In the present study we used gas chromatography-mass spectrometry to analyze tobacco as well as mainstream and second hand smoke for 3-hydroxy fatty acids (3-OH FAs) of 10 to 18 carbon chain lengths, used as LPS markers, and ergosterol, used as a marker of fungal biomass. The air concentrations of LPS were 0.0017 nmol/m{sup 3} (N = 5) and 0.0007/m{sup 3} (N = 6) in the smoking vs. non-smoking rooms (p = 0.0559) of the studied private houses, and 0.0231 nmol/m{sup 3} (N = 5) vs. 0.0006 nmol/m{sup 3} (N = 5) (p = 0.0173), respectively, at the worksite. The air concentrations of ergosterol were also significantly higher in rooms with ongoing smoking than in rooms without smoking. A positive correlation was found between LPS and ergosterol in rooms with smoking but not in rooms without smoking. 3-OH C14:0 was the main 3-OH FA, followed by 3-OH C12:0, both in mainstream and second hand smoke and in phenol:water smoke extracts prepared in order to purify the LPS. The Limulus activity of the phenolic phase of tobacco was 3900 endotoxin units (EU)/cigarette; the corresponding amount of the smoke, collected on filters from 8 puffs, was 4 EU/cigarette. Tobacco smoking has been associated with a range of inflammatory airway conditions including COPD, asthma, bronchitis, alveolar hypersensitivity etc. Significant levels of LPS and ergosterol were identified in tobacco smoke and these observations support the hypothesis that microbial components of tobacco smoke contribute to inflammation and airway disease. -- Highlights: Black-Right-Pointing-Pointer Air concentration of bacterial and fungal markers is significantly higher in rooms with ongoing smoking than without smoking. Black-Right-Pointing-Pointer Bacterial LPS correlates with fungal marker in rooms with ongoing smoking but not without smoking. Black-Right-Pointing-Pointer LPS

  1. Extracellular biosynthesis of CdTe quantum dots by the fungus Fusarium oxysporum and their anti-bacterial activity

    Science.gov (United States)

    Syed, Asad; Ahmad, Absar

    2013-04-01

    The growing demand for semiconductor [quantum dots (Q-dots)] nanoparticles has fuelled significant research in developing strategies for their synthesis and characterization. They are extensively investigated by the chemical route; on the other hand, use of microbial sources for biosynthesis witnessed the highly stable, water dispersible nanoparticles formation. Here we report, for the first time, an efficient fungal-mediated synthesis of highly fluorescent CdTe quantum dots at ambient conditions by the fungus Fusarium oxysporum when reacted with a mixture of CdCl2 and TeCl4. Characterization of these biosynthesized nanoparticles was carried out by different techniques such as Ultraviolet-visible (UV-Vis) spectroscopy, Photoluminescence (PL), X-ray Diffraction (XRD), X-ray Photoelectron spectroscopy (XPS), Transmission Electron Microscopy (TEM) and Fourier Transformed Infrared Spectroscopy (FTIR) analysis. CdTe nanoparticles shows antibacterial activity against Gram positive and Gram negative bacteria. The fungal based fabrication provides an economical, green chemistry approach for production of highly fluorescent CdTe quantum dots.

  2. Regulation of Fumonisin B1 Biosynthesis and Conidiation in Fusarium verticillioides by a Cyclin-Like (C-Type) Gene, FCC1†

    Science.gov (United States)

    Shim, Won-Bo; Woloshuk, Charles P.

    2001-01-01

    Fumonisins are a group of mycotoxins produced in corn kernels by the plant-pathogenic fungus Fusarium verticillioides. A mutant of the fungus, FT536, carrying a disrupted gene named FCC1 (for Fusarium cyclin C1) resulting in altered fumonisin B1 biosynthesis was generated. FCC1 contains an open reading frame of 1,018 bp, with one intron, and encodes a putative 319-amino-acid polypeptide. This protein is similar to UME3 (also called SRB11 or SSN8), a cyclin C of Saccharomyces cerevisiae, and contains three conserved motifs: a cyclin box, a PEST-rich region, and a destruction box. Also similar to the case for C-type cyclins, FCC1 was constitutively expressed during growth. When strain FT536 was grown on corn kernels or on defined minimal medium at pH 6, conidiation was reduced and FUM5, the polyketide synthase gene involved in fumonisin B1 biosynthesis, was not expressed. However, when the mutant was grown on a defined minimal medium at pH 3, conidiation was restored, and the blocks in expression of FUM5 and fumonisin B1 production were suppressed. Our data suggest that FCC1 plays an important role in signal transduction regulating secondary metabolism (fumonisin biosynthesis) and fungal development (conidiation) in F. verticillioides. PMID:11282612

  3. Fungal osteomyelitis with vertebral re-ossification.

    Science.gov (United States)

    O Guinn, Devon J; Serletis, Demitre; Kazemi, Noojan

    2016-01-01

    We present a rare case of thoracic vertebral osteomyelitis secondary to pulmonary Blastomyces dermatitides. A 27-year-old male presented with three months of chest pains and non-productive cough. Examination revealed diminished breath sounds on the right. CT/MR imaging confirmed a right-sided pre-/paravertebral soft tissue mass and destructive lytic lesions from T2 to T6. CT-guided needle biopsy confirmed granulomatous pulmonary Blastomycosis. Conservative management with antifungal therapy was initiated. Neurosurgical review confirmed no clinical or profound radiographic instability, and the patient was stabilized with TLSO bracing. Serial imaging 3 months later revealed near-resolution of the thoracic soft tissue mass, with vertebral re-ossification from T2 to T6. Fungal osteomyelitis presents a rare entity in the spectrum of spinal infections. In such cases, lytic spinal lesions are classically seen in association with a large paraspinous mass. Fungal infections of the spinal column may be treated conservatively, with surgical intervention reserved for progressive cases manifesting with neurological compromise and/or spinal column instability. Here, we found unexpected evidence for vertebral re-ossification across the affected thoracic levels (T2-6) in response to IV antibiotic therapy and conservative bracing, nearly 3 months later. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Fungal biomass production from coffee pulp juice

    Energy Technology Data Exchange (ETDEWEB)

    De Leon, R.; Calzada, F.; Herrera, R.; Rolz, C.

    1980-01-01

    Coffee pulp or skin represents about 40% of the weight of the fresh coffee fruit. It is currently a waste and its improper handling creates serious pollution problems for coffee producing countries. Mechanical pressing of the pulp will produce two fractions: coffee pulp juice (CPJ) and pressed pulp. Aspergillus oryzae, Trichoderma harzianum, Penicillium crustosum and Gliocladium deliquescens grew well in supplemented CPJ. At shake flask level the optimum initial C/N ratio was found to be in the range of 8 to 14. At this scale, biomass values of up to 50 g/l were obtained in 24 hours. Biomass production and total sugar consumption were not significantly different to all fungal species tested at the bench-scale level, even when the initial C/N ratio was varied. Best nitrogen consumption values were obtained when the initial C/N ratio was 12. Maximum specific growth rates occurred between 4-12 hours for all fungal species tested. (Refs. 8).

  5. Sexual Reproduction of Human Fungal Pathogens

    Science.gov (United States)

    Heitman, Joseph; Carter, Dee A.; Dyer, Paul S.; Soll, David R.

    2014-01-01

    We review here recent advances in our understanding of sexual reproduction in fungal pathogens that commonly infect humans, including Candida albicans, Cryptococcus neoformans/gattii, and Aspergillus fumigatus. Where appropriate or relevant, we introduce findings on other species associated with human infections. In particular, we focus on rapid advances involving genetic, genomic, and population genetic approaches that have reshaped our view of how fungal pathogens evolve. Rather than being asexual, mitotic, and largely clonal, as was thought to be prevalent as recently as a decade ago, we now appreciate that the vast majority of pathogenic fungi have retained extant sexual, or parasexual, cycles. In some examples, sexual and parasexual unions of pathogenic fungi involve closely related individuals, generating diversity in the population but with more restricted recombination than expected from fertile, sexual, outcrossing and recombining populations. In other cases, species and isolates participate in global outcrossing populations with the capacity for considerable levels of gene flow. These findings illustrate general principles of eukaryotic pathogen emergence with relevance for other fungi, parasitic eukaryotic pathogens, and both unicellular and multicellular eukaryotic organisms. PMID:25085958

  6. Burden of serious fungal infections in Mexico.

    Science.gov (United States)

    Corzo-León, D E; Armstrong-James, D; Denning, D W

    2015-10-01

    Serious fungal infections (SFIs) could be more frequent than are recognised. Estimates of the incidence and prevalence of SFIs are essential in order to identify public health problems. We estimated the rates of SFIs in Mexico, following a methodology similar to that used in prior studies. We obtained information about the general population and populations at risk. A systematic literature search was undertaken to identify epidemiological reports of SFIs in Mexico. When Mexican reports were unavailable, we based our estimates on international literature. The most prevalent SFIs in Mexico are recurrent vulvovaginal candidiasis (5999 per 100,000) followed by allergic bronchopulmonary aspergillosis (60 per 100,000), chronic pulmonary aspergillosis (15.9 per 100,000), fungal keratitis (10.4 per 100,000), invasive candidiasis (8.6 per 100,000) and SFIs in HIV (8.2 per 100,000); coccidioidomycosis (7.6 per 100,000), IA (4.56 per 100,000). These correspond to 2,749,159 people affected in any year (2.45% of the population), probably >10,000 deaths and 7000 blind eyes. SFIs affect immunocompromised and healthy populations. Most are associated with high morbidity and mortality rates. Validation of these estimates with epidemiological studies is required. The burdens indicate that an urgent need to improve medical skills, surveillance, diagnosis, and management of SFIs exists. © 2015 Blackwell Verlag GmbH.

  7. Structural Insight into the Core of CAD, the Multifunctional Protein Leading De Novo Pyrimidine Biosynthesis.

    Science.gov (United States)

    Moreno-Morcillo, María; Grande-García, Araceli; Ruiz-Ramos, Alba; Del Caño-Ochoa, Francisco; Boskovic, Jasminka; Ramón-Maiques, Santiago

    2017-06-06

    CAD, the multifunctional protein initiating and controlling de novo biosynthesis of pyrimidines in animals, self-assembles into ∼1.5 MDa hexamers. The structures of the dihydroorotase (DHO) and aspartate transcarbamoylase (ATC) domains of human CAD have been previously determined, but we lack information on how these domains associate and interact with the rest of CAD forming a multienzymatic unit. Here, we prove that a construct covering human DHO and ATC oligomerizes as a dimer of trimers and that this arrangement is conserved in CAD-like from fungi, which holds an inactive DHO-like domain. The crystal structures of the ATC trimer and DHO-like dimer from the fungus Chaetomium thermophilum confirm the similarity with the human CAD homologs. These results demonstrate that, despite being inactive, the fungal DHO-like domain has a conserved structural function. We propose a model that sets the DHO and ATC complex as the central element in the architecture of CAD. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Function and Biosynthesis of Cell Wall α-1,3-Glucan in Fungi

    Directory of Open Access Journals (Sweden)

    Akira Yoshimi

    2017-11-01

    Full Text Available Although α-1,3-glucan is a major cell wall polysaccharide in filamentous fungi, its biological functions remain unclear, except that it acts as a virulence factor in animal and plant pathogenic fungi: it conceals cell wall β-glucan on the fungal cell surface to circumvent recognition by hosts. However, cell wall α-1,3-glucan is also present in many of non-pathogenic fungi. Recently, the universal function of α-1,3-glucan as an aggregation factor has been demonstrated. Applications of fungi with modified cell wall α-1,3-glucan in the fermentation industry and of in vitro enzymatically-synthesized α-1,3-glucan in bio-plastics have been developed. This review focuses on the recent progress in our understanding of the biological functions and biosynthetic mechanism of cell wall α-1,3-glucan in fungi. We briefly consider the history of studies on α-1,3-glucan, overview its biological functions and biosynthesis, and finally consider the industrial applications of fungi deficient in α-1,3-glucan.

  9. Fusarium proliferatum strains change fumonisin biosynthesis and accumulation when exposed to host plant extracts.

    Science.gov (United States)

    Górna, Karolina; Pawłowicz, Izabela; Waśkiewicz, Agnieszka; Stępień, Łukasz

    2016-01-01

    Fumonisin concentrations in mycelia and media were studied in liquid Fusarium proliferatum cultures supplemented with host plant extracts. Furthermore, the kinetics of fumonisin accumulation in media and mycelia collected before and after extract addition was analysed as well as the changes in the expression of the FUM1 gene. Fumonisin content in culture media increased in almost all F. proliferatum strains shortly after plant extracts were added. The asparagus extract induced the highest FB level increase and the garlic extract was the second most effective inducer. Fumonisin level decreased constantly until 14th day of culturing, though for some strains also at day 8th an elevated FB level was observed. Pineapple extract induced the highest increase of fum1 transcript levels as well as fumonisin synthesis in many strains, and the peas extract inhibited fungal growth and fumonisin biosynthesis. Moreover, fumonisins were accumulated in mycelia of studied strains and in the respective media. Copyright © 2016 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  10. Fenarimol, a Pyrimidine-Type Fungicide, Inhibits Brassinosteroid Biosynthesis

    Directory of Open Access Journals (Sweden)

    Keimei Oh

    2015-07-01

    Full Text Available The plant steroid hormone brassinosteroids (BRs are important signal mediators that regulate broad aspects of plant growth and development. With the discovery of brassinoazole (Brz, the first specific inhibitor of BR biosynthesis, several triazole-type BR biosynthesis inhibitors have been developed. In this article, we report that fenarimol (FM, a pyrimidine-type fungicide, exhibits potent inhibitory activity against BR biosynthesis. FM induces dwarfism and the open cotyledon phenotype of Arabidopsis seedlings in the dark. The IC50 value for FM to inhibit stem elongation of Arabidopsis seedlings grown in the dark was approximately 1.8 ± 0.2 μM. FM-induced dwarfism of Arabidopsis seedlings could be restored by brassinolide (BL but not by gibberellin (GA. Assessment of the target site of FM in BR biosynthesis by feeding BR biosynthesis intermediates indicated that FM interferes with the side chain hydroxylation of BR biosynthesis from campestanol to teasterone. Determination of the binding affinity of FM to purified recombinant CYP90D1 indicated that FM induced a typical type II binding spectrum with a Kd value of approximately 0.79 μM. Quantitative real-time PCR analysis of the expression level of the BR responsive gene in Arabidopsis seedlings indicated that FM induces the BR deficiency in Arabidopsis.

  11. Regulation of Strigolactone Biosynthesis by Gibberellin Signaling.

    Science.gov (United States)

    Ito, Shinsaku; Yamagami, Daichi; Umehara, Mikihisa; Hanada, Atsushi; Yoshida, Satoko; Sasaki, Yasuyuki; Yajima, Shunsuke; Kyozuka, Junko; Ueguchi-Tanaka, Miyako; Matsuoka, Makoto; Shirasu, Ken; Yamaguchi, Shinjiro; Asami, Tadao

    2017-06-01

    Strigolactones (SLs) are a class of plant hormones that regulate diverse physiological processes, including shoot branching and root development. They also act as rhizosphere signaling molecules to stimulate the germination of root parasitic weeds and the branching of arbuscular mycorrhizal fungi. Although various types of cross talk between SLs and other hormones have been reported in physiological analyses, the cross talk between gibberellin (GA) and SLs is poorly understood. We screened for chemicals that regulate the level of SLs in rice ( Oryza sativa ) and identified GA as, to our knowledge, a novel SL-regulating molecule. The regulation of SL biosynthesis by GA is dependent on the GA receptor GID1 and F-box protein GID2. GA treatment also reduced the infection of rice plants by the parasitic plant witchers weed ( Striga hermonthica ). These data not only demonstrate, to our knowledge, the novel plant hormone cross talk between SL and GA, but also suggest that GA can be used to control parasitic weed infections. © 2017 American Society of Plant Biologists. All Rights Reserved.

  12. Estrogen biosynthesis in human uterine adenomyosis

    International Nuclear Information System (INIS)

    Urabe, Mamoru; Yamamoto, Takara; Kitawaki, Jo; Honjo, Hideo; Okada, Hiroji

    1989-01-01

    Estrogen biosynthesis (aromatiase activity) was investigated in human adenomyosis tissue and compared with that of the normal myometrium, endometrium, and endometrical cancer tissues. Homogenates were incubated with [1,2,6,7- 3 H]androstenedione and NADPH at 37 deg. C for 1 h. After stopping the enzymatic reaction with ethyl acetate, [4- 14 C]estrone and [4- 14 C]estradiol-17β were added to the incubated sample. Estrone and estradiol were purified and identified by Bio-Rad AG1-X2 column chromatography, thin-layer chromatography and co-crystallization. Estrogen formed in the incubated sample was calculated from the 3 H/ 14 C ratio of the final crystal. The value for estrone formed from androstenedione was 52-132 fmol . h -1. g -1 wet weight. Aromatase activity in the adenomyosis tissues was higher than that in normal endometrial or myometrial tissues, but lower than that found in myometrial or endometrial tumour tissue. Furthermore, we investigated the effect of danazol, progresterone, and medroxyprogesterone acetate on adenomyosis cells in primary cultures. Aromatase activity in adenomyosis was blocked by danazol, but stimulated by progesterone and MPA. These results indicate that aromatase activity in adenomyosis may contribute to the growth of the ectopic endometrial tissue which occurs in this disease. (author)

  13. A Biotin Biosynthesis Gene Restricted to Helicobacter

    Science.gov (United States)

    Bi, Hongkai; Zhu, Lei; Jia, Jia; Cronan, John E.

    2016-01-01

    In most bacteria the last step in synthesis of the pimelate moiety of biotin is cleavage of the ester bond of pimeloyl-acyl carrier protein (ACP) methyl ester. The paradigm cleavage enzyme is Escherichia coli BioH which together with the BioC methyltransferase allows synthesis of the pimelate moiety by a modified fatty acid biosynthetic pathway. Analyses of the extant bacterial genomes showed that bioH is absent from many bioC-containing bacteria and is replaced by other genes. Helicobacter pylori lacks a gene encoding a homologue of the known pimeloyl-ACP methyl ester cleavage enzymes suggesting that it encodes a novel enzyme that cleaves this intermediate. We isolated the H. pylori gene encoding this enzyme, bioV, by complementation of an E. coli bioH deletion strain. Purified BioV cleaved the physiological substrate, pimeloyl-ACP methyl ester to pimeloyl-ACP by use of a catalytic triad, each member of which was essential for activity. The role of BioV in biotin biosynthesis was demonstrated using a reconstituted in vitro desthiobiotin synthesis system. BioV homologues seem the sole pimeloyl-ACP methyl ester esterase present in the Helicobacter species and their occurrence only in H. pylori and close relatives provide a target for development of drugs to specifically treat Helicobacter infections. PMID:26868423

  14. Explorations into the biosynthesis of bioscorine

    International Nuclear Information System (INIS)

    Michelson, R.H.

    1988-01-01

    The biosynthesis of dioscorine in Dioscorea hispida has been studied by the feeding of putative precursors labelled at specific positions with 2 H, 3 H, and 14 C. Administration of [3- 14 C]3-hydroxy-3-methylglutaric acid to D. hispida by the wick method afforded dioscorine labelled preferentially at the C 10 position implying that the biosynthetic pathway to the acetate-derived half of the dioscorine skeleton is going through this compound. Administration of ethyl [6- 14 C]orsellinate to D. hispida by the wick method failed to give an appreciable incorporation into dioscroine thereby disproving an alternative mechanism describing the formation of the acetate-derived half of the dioscorine skeleton. Two attempts to simulate the alternative mechanism by oxidatively cleaving ethyl orsellinate also failed, further disfavoring this mechanism. Administration of [2,3] 13 C 2 , 14 C 2 succinic acid, [3- 14 C]aspartic acid and [7a- 14 C]tryptophan by the leaf painting method gave very low incorporations into dioscorine making determination of the source of the nicotinic acid half of the dioscorine skeleton inconclusive. Administration of [6- 2 H, 3 H]nicotinic acid to D. hispida by the wick method afforded dioscorine exhibiting complete retention of 3 H thereby disfavoring a mechanism involving a 3,6-dihydropyridine intermediate in the formation of the dioscorine skeleton

  15. Transcriptional analysis of apple fruit proanthocyanidin biosynthesis

    Science.gov (United States)

    Henry-Kirk, Rebecca A.

    2012-01-01

    Proanthocyanidins (PAs) are products of the flavonoid pathway, which also leads to the production of anthocyanins and flavonols. Many flavonoids have antioxidant properties and may have beneficial effects for human health. PAs are found in the seeds and fruits of many plants. In apple fruit (Malus × domestica Borkh.), the flavonoid biosynthetic pathway is most active in the skin, with the flavan-3-ols, catechin, and epicatechin acting as the initiating units for the synthesis of PA polymers. This study examined the genes involved in the production of PAs in three apple cultivars: two heritage apple cultivars, Hetlina and Devonshire Quarrenden, and a commercial cultivar, Royal Gala. HPLC analysis shows that tree-ripe fruit from Hetlina and Devonshire Quarrenden had a higher phenolic content than Royal Gala. Epicatechin and catechin biosynthesis is under the control of the biosynthetic enzymes anthocyanidin reductase (ANR) and leucoanthocyanidin reductase (LAR1), respectively. Counter-intuitively, real-time quantitative PCR analysis showed that the expression levels of Royal Gala LAR1 and ANR were significantly higher than those of both Devonshire Quarrenden and Hetlina. This suggests that a compensatory feedback mechanism may be active, whereby low concentrations of PAs may induce higher expression of gene transcripts. Further investigation is required into the regulation of these key enzymes in apple. Abbreviations:ANOVAanalysis of varianceANRanthocyanidin reductaseDADdiode array detectorDAFBdays after full bloomDFRdihydroflavonol reductaseLARleucoanthocyanidin reductaseLC-MSliquid chromatography/mass spectrometryPAproanthocyanidinqPCRreal-time quantitative PCR PMID:22859681

  16. The regulation and biosynthesis of antimycins

    Directory of Open Access Journals (Sweden)

    Ryan F. Seipke

    2013-11-01

    Full Text Available Antimycins (>40 members were discovered nearly 65 years ago but the discovery of the gene cluster encoding antimycin biosynthesis in 2011 has facilitated rapid progress in understanding the unusual biosynthetic pathway. Antimycin A is widely used as a piscicide in the catfish farming industry and also has potent killing activity against insects, nematodes and fungi. The mode of action of antimycins is to inhibit cytochrome c reductase in the electron transport chain and halt respiration. However, more recently, antimycin A has attracted attention as a potent and selective inhibitor of the mitochondrial anti-apoptotic proteins Bcl-2 and Bcl-xL. Remarkably, this inhibition is independent of the main mode of action of antimycins such that an artificial derivative named 2-methoxyantimycin A inhibits Bcl-xL but does not inhibit respiration. The Bcl-2/Bcl-xL family of proteins are over-produced in cancer cells that are resistant to apoptosis-inducing chemotherapy agents, so antimycins have great potential as anticancer drugs used in combination with existing chemotherapeutics. Here we review what is known about antimycins, the regulation of the ant gene cluster and the unusual biosynthetic pathway.

  17. Engineering bacteria for enhanced polyhydroxyalkanoates (PHA biosynthesis

    Directory of Open Access Journals (Sweden)

    Guo-Qiang Chen

    2017-09-01

    Full Text Available Polyhydroxyalkanoates (PHA have been produced by some bacteria as bioplastics for many years. Yet their commercialization is still on the way. A few issues are related to the difficulty of PHA commercialization: namely, high cost and instabilities on molecular weights (Mw and structures, thus instability on thermo-mechanical properties. The high cost is the result of complicated bioprocessing associated with sterilization, low conversion of carbon substrates to PHA products, and slow growth of microorganisms as well as difficulty of downstream separation. Future engineering on PHA producing microorganisms should be focused on contamination resistant bacteria especially extremophiles, developments of engineering approaches for the extremophiles, increase on carbon substrates to PHA conversion and controlling Mw of PHA. The concept proof studies could still be conducted on E. coli or Pseudomonas spp. that are easily used for molecular manipulations. In this review, we will use E. coli and halophiles as examples to show how to engineer bacteria for enhanced PHA biosynthesis and for increasing PHA competitiveness.

  18. Biosynthesis of myristic acid in luminescent bacteria

    International Nuclear Information System (INIS)

    Byers, D.M.

    1987-01-01

    In vivo pulse-label studies have demonstrated that luminescent bacteria can provide myritic acid (14:0) required for the synthesis of the luciferase substrate myristyl aldehyde. Luminescent wild type Vibrio harveyi incubated with [ 14 C] acetate in a nutrient-depleted medium accumulated substantial tree [ 14 C]fatty acid (up to 20% of the total lipid label). Radio-gas chromatography revealed that > 75% of the labeled fatty acid is 14:0. No free fatty acid was detected in wild type cells labeled prior to the development of bioluminescence in the exponential growth phase, or in a dark mutant of V. harveyi (mutant M17) that requires exogenous 14:0 for light emission. The preferential accumulation of 14:0 was not observed when wild type cells were labeled with [ 14 C]acetate in regular growth medium. Moreover, all V. harveyi strains exhibited similar fatty acid mass compositions regardless of the state of bioluminescence. Since earlier work has shown that a luminescence-related acyltransferase (defective in the M17 mutant) can catalyze the deacylation of fatty acyl-acyl carrier protein in vitro, the present results are consistent with a model in which this enzyme diverts 14:0 to the luminescence system during fatty acid biosynthesis. Under normal conditions, the supply of 14:0 by this pathway is tightly regulated such that bioluminescence development does not significantly alter the total fatty acid composition

  19. Biosynthesis of plasmenylcholine in guinea pig heart

    International Nuclear Information System (INIS)

    Wientzek, M.; Choy, P.C.

    1986-01-01

    In some mammalian hearts, up to 40% of the choline phosphoglyceride (CPG) exists as plasmenylcholine (1-alkenyl-2-acyl-glycero-3-phosphocholine). Although the majority of diacylphosphatidylcholine (PC) in mammalian hearts is synthesized from choline via the CDP-choline pathway, the formation of plasmenylcholine from choline was not known. In this study, they investigated the biosynthesis of plasmenyl-choline in the isolated guinea pig heart by perfusion with [ 3 H]choline. Labelled choline containing metabolites and labelled plasmenylcholine were isolated and determined at different perfusion time points. Significant amounts of labelling were found only in choline, phosphocholine, CDP-choline, plasmenyl-choline and PC. In addition, a precursor-product relationship was observed between the labelling of CDP-choline and plasmenylcholine. Such a relationship was not observed between choline and plasmenylcholine. Hence, they postulate that the incorporation of choline into plasmenylcholine is via the CDP-choline pathway and not via base exchange. The ability to condense 1-alkenyl-2-acyl-glycerol with CDP-choline was also demonstrated in vitro with guinea pig heart microsomes

  20. Biosynthesis of secondary metabolites in sugarcane

    Directory of Open Access Journals (Sweden)

    S.C. França

    2001-12-01

    Full Text Available A set of genes related to secondary metabolism was extracted from the sugarcane expressed sequence tag (SUCEST database and was used to investigate both the gene expression pattern of key enzymes regulating the main biosynthetic secondary metabolism pathways and the major classes of metabolites involved in the response of sugarcane to environmental and developmental cues. The SUCEST database was constructed with tissues in different physiological conditions which had been collected under varied situation of environmental stress. This database allows researchers to identify and characterize the expressed genes of a wide range of putative enzymes able to catalyze steps in the phenylpropanoid, isoprenoid and other pathways of the special metabolic mechanisms involved in the response of sugarcane to environmental changes. Our results show that sugarcane cDNAs encoded putative ultra-violet induced sesquiterpene cyclases (SC; chalcone synthase (CHS, the first enzyme in the pathway branch for flavonoid biosynthesis; isoflavone synthase (IFS, involved in plant defense and root nodulation; isoflavone reductase (IFR, a key enzyme in phenylpropanoid phytoalexin biosynthesis; and caffeic acid-O-methyltransferase, a key enzyme in the biosynthesis of lignin cell wall precursors. High levels of CHS transcripts from plantlets infected with Herbaspirillum rubri or Gluconacetobacter diazotroficans suggests that agents of biotic stress can elicit flavonoid biosynthesis in sugarcane. From this data we have predicted the profile of isoprenoid and phenylpropanoid metabolism in sugarcane and pointed the branches of secondary metabolism activated during tissue-specific stages of development and the adaptive response of sugarcane to agents of biotic and abiotic stress, although our assignment of enzyme function should be confirmed by careful biochemical and genetic supporting evidence.Este trabalho foi realizado com os objetivos de gerar uma coleção de genes

  1. Tyrosine biosynthesis, metabolism, and catabolism in plants.

    Science.gov (United States)

    Schenck, Craig A; Maeda, Hiroshi A

    2018-05-01

    L-Tyrosine (Tyr) is an aromatic amino acid (AAA) required for protein synthesis in all organisms, but synthesized de novo only in plants and microorganisms. In plants, Tyr also serves as a precursor of numerous specialized metabolites that have diverse physiological roles as electron carriers, antioxidants, attractants, and defense compounds. Some of these Tyr-derived plant natural products are also used in human medicine and nutrition (e.g. morphine and vitamin E). While the Tyr biosynthesis and catabolic pathways have been extensively studied in microbes and animals, respectively, those of plants have received much less attention until recently. Accumulating evidence suggest that the Tyr biosynthetic pathways differ between microbes and plants and even within the plant kingdom, likely to support the production of lineage-specific plant specialized metabolites derived from Tyr. The interspecies variations of plant Tyr pathway enzymes can now be used to enhance the production of Tyr and Tyr-derived compounds in plants and other synthetic biology platforms. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Glycoprotein biosynthesis by human normal platelets

    International Nuclear Information System (INIS)

    Rodriguez, P.; Bello, O.; Apitz-Castro, R.

    1987-01-01

    Incorporation of radioactive Man, Gal, Fuc, Glc-N, and NANA into washed human normal platelets and endogenous glycoproteins has been found. Both parameters were time dependent. Analysis of hydrolyzed labeled glycoproteins by paper chromatography revealed that the radioactive monosaccharide incubated with the platelets had not been converted into other sugars. Acid hydrolysis demonstrates the presence of a glycosidic linkage. All the effort directed to the demonstration of the existence of a lipid-sugar intermediate in intact human platelets yielded negative results for Man and Glc-N used as precursors. The incorporation of these sugars into glycoproteins is insensitive to bacitracin, suggesting no involvement of lipid-linked saccharides in the synthesis of glycoproteins in human blood platelets. The absence of inhibition of the glycosylation process in the presence of cycloheximide suggests that the sugars are added to proteins present in the intact platelets. These results support the contention that glycoprotein biosynthesis in human blood platelets observed under our experimental conditions is effected through direct sugar nucleotide glycosylation

  3. Preliminary studies of the biosynthesis of Austin

    International Nuclear Information System (INIS)

    Wicnienski, N.A.

    1979-01-01

    Aspergillus ustus is one of the most prevalent fungi in the soil. There are now two reports of the occurrence of toxin-producing strains of this fungus on stored foodstuffs. In addition, strains of A. ustus have been isolated along with Penicillium species from samples of South African cheeses. All A. ustus isolates tested were judged to be highly toxic to ducklings when grown on maize meal, however, the toxins involved were not isolated. Austin is the trivial name of one of the toxins made by the fungus found on stored food. Preliminary work to studying the biosynthesis of this compound using 13 C-labeled sodium acetate is reported here. The feasibility of the biosynthetic study was determined by feeding [1- 14 C]-sodium acetate to A. ustus cultures. The assignments made in the 13 C-nmr spectrum of Austin are shown. The lowest dilution factor obtained in [1- 14 C]-sodium acetate feeding experiments was 14. This dilution factor is sufficiently low to allow a successful feeding of [1,2- 13 C 2 ]-sodium acetate. A new metabolite of A. ustus, deacetylaustin, was isolated and identified. An alkaloid of unknown structure was also isolated from the fungus

  4. Physicochemical Properties of Fungal Detoxified Cassava Mash and ...

    African Journals Online (AJOL)

    The physicochemical properties of fungal detoxified cassava mash and sensory characteristics of wheat-detoxified cassava composite doughnuts were investigated. Fungal isolates from soils collected at cassava processing sites were isolated, quantified and identified. Cassava mash from grated tuber was partially ...

  5. The Top 10 fungal pathogens in molecular plant pathology

    NARCIS (Netherlands)

    Dean, R.; Kan, van J.A.L.; Pretorius, Z.A.; Hammond-Kosack, K.E.; Pietro, Di A.; Spanu, P.D.; Rudd, J.J.; Dickman, M.; Kahmann, R.; Ellis, J.; Foster, G.D.

    2012-01-01

    The aim of this review was to survey all fungal pathologists with an association with the journal Molecular Plant Pathology and ask them to nominate which fungal pathogens they would place in a ‘Top 10’ based on scientific/economic importance. The survey generated 495 votes from the international

  6. Chronic invasive fungal granulomatous rhino-sinusitis: a case report ...

    African Journals Online (AJOL)

    Fungal Rhino-Sinusitis (FRS) is a relatively uncommon entity. The chronic invasive granulomatous form of FRS (FGRS) is a slowly progressive form of fungal infection characterized by chronic granulomatous process with a time course of longer than 12 weeks. The aim of this report is to draw the attention of colleagues to ...

  7. First genomic survey of human skin fungal diversity

    Science.gov (United States)

    Fungal infections of the skin affect 29 million people in the United States. In the first study of human fungal skin diversity, National Institutes of Health researchers sequenced the DNA of fungi that thrive at different skin sites of healthy adults to d

  8. Studies on the fungal flora of Garri, processed cassava ( Manihot ...

    African Journals Online (AJOL)

    In Nsukka area of southeastern Nigeria, garri is usually displayed in the open market for sale which no doubt exposes the food stuff to dust particles from moving vehicles, wind and other sources. Thus, fungal spores from the air and soil environment could serve as major sources of fungal contamination of this product.

  9. Isolation and identification of fungal species from dried date palm ...

    African Journals Online (AJOL)

    A total of 360 dried date palm (Phoenix dactylifera) fruits were collected from hawkers, shops and market places within Maiduguri metropolis for the detection of the presence of fungal species. Investigation was based on cultural, microscopically and biochemical tests. Of the 327 (90.83%) fungal isolates recovered on ...

  10. Production of Microbial Protease from Selected Soil Fungal Isolates ...

    African Journals Online (AJOL)

    Production of Microbial Protease from Selected Soil Fungal Isolates. ... Nigerian Journal of Biotechnology ... and 500C. The optimal pH on the enzyme production was observed to be between pH 3.5 and 5.5 for the organisms. Keywords: Soil microorganism, fungal isolate, incubation period, microbial enzyme. Nig J. Biotech.

  11. New perspectives towards analising fungal communities in terrestrial environments

    NARCIS (Netherlands)

    Kowalchuk, G.A.

    1999-01-01

    Fungi play key roles in numerous ecosystem functions, and recent advances in the study of fungal diversity and ecology have led to a greater appreciation of this group of microeukaryotes. The application of a variety of nucleic acid techniques to fungal classification and phylogeny has led to a

  12. Inositol Polyphosphate Kinases, Fungal Virulence and Drug Discovery

    Directory of Open Access Journals (Sweden)

    Cecilia Li

    2016-09-01

    Full Text Available Opportunistic fungi are a major cause of morbidity and mortality world-wide, particularly in immunocompromised individuals. Developing new treatments to combat invasive fungal disease is challenging given that fungal and mammalian host cells are eukaryotic, with similar organization and physiology. Even therapies targeting unique fungal cell features have limitations and drug resistance is emerging. New approaches to the development of antifungal drugs are therefore needed urgently. Cryptococcus neoformans, the commonest cause of fungal meningitis worldwide, is an accepted model for studying fungal pathogenicity and driving drug discovery. We recently characterized a phospholipase C (Plc1-dependent pathway in C. neoformans comprising of sequentially-acting inositol polyphosphate kinases (IPK, which are involved in synthesizing inositol polyphosphates (IP. We also showed that the pathway is essential for fungal cellular function and pathogenicity. The IP products of the pathway are structurally diverse, each consisting of an inositol ring, with phosphate (P and pyrophosphate (PP groups covalently attached at different positions. This review focuses on (1 the characterization of the Plc1/IPK pathway in C. neoformans; (2 the identification of PP-IP5 (IP7 as the most crucial IP species for fungal fitness and virulence in a mouse model of fungal infection; and (3 why IPK enzymes represent suitable candidates for drug development.

  13. Structure of fungal oxyluciferin, the product of the bioluminescence reaction.

    Science.gov (United States)

    Purtov, K V; Osipova, Z M; Petushkov, V N; Rodionova, N S; Tsarkova, A S; Kotlobay, A A; Chepurnykh, T V; Gorokhovatsky, A Yu; Yampolsky, I V; Gitelson, J I

    2017-11-01

    The structure of fungal oxyluciferin was determined, the enzymatic bioluminescence reaction under substrate saturation conditions with discrete monitoring of formed products was conducted, and the structures of the end products of the reaction were established. On the basis of these studies, the scheme of oxyluciferin degradation to the end products was developed. The structure of fungal oxyluciferin was confirmed by counter synthesis.

  14. Acute fungal sinusitis in neutropenic patients of Namazi hospital/ Shiraz

    Directory of Open Access Journals (Sweden)

    Parisa Badiee

    2008-09-01

    Full Text Available Introduction: Fungal sinusitis is a well known disease in immunocompromised patients, but recently many reports have indicated an increased prevalence of fungal sinusitis in otherwise healthy individuals. The aim of this study was to assess the frequency of invasive fungal sinusitis (IFS in neutropenic patients and to determine outcome factors that may affect their survival. Methods: A total of 142 patients who were undergoing chemotherapy were followed by clinical and radiological features suggestive of fungal sinusitis. Patients with fever, headache, facial swelling and radiological finding underwent endoscopic sinus surgery. The biopsy materials were studied by mycological and histopathological methods. Results: Eleven from 142 patients were identified to have IFS. The ethiologic agents were Aspergillus flavus (5 cases, Alternaria sp. (3 cases, Aspergillus fumigatus (2 cases and mucor (1 case. Eight of 11 cases died. Conclusions: Invasive fungal sinusitis causes a high rate of mortality among immunocompromised patients. Therefore, early diagnosis with aggressive medical and surgical intervention is critical for survival.

  15. The Interface between Fungal Biofilms and Innate Immunity

    Directory of Open Access Journals (Sweden)

    John F. Kernien

    2018-01-01

    Full Text Available Fungal biofilms are communities of adherent cells surrounded by an extracellular matrix. These biofilms are commonly found during infection caused by a variety of fungal pathogens. Clinically, biofilm infections can be extremely difficult to eradicate due to their resistance to antifungals and host defenses. Biofilm formation can protect fungal pathogens from many aspects of the innate immune system, including killing by neutrophils and monocytes. Altered immune recognition during this phase of growth is also evident by changes in the cytokine profiles of monocytes and macrophages exposed to biofilm. In this manuscript, we review the host response to fungal biofilms, focusing on how these structures are recognized by the innate immune system. Biofilms formed by Candida, Aspergillus, and Cryptococcus have received the most attention and are highlighted. We describe common themes involved in the resilience of fungal biofilms to host immunity and give examples of biofilm defenses that are pathogen-specific.

  16. Fungal endophytes characterization from four species of Diplazium Swartz

    Science.gov (United States)

    Affina-Eliya, A. A.; Noraini, T.; Nazlina, I.; Ruzi, A. R.

    2014-09-01

    Four species on genus Diplazium namely Diplazium tomentosum, D. sorzogonense, D. asperum and D. accedens of Peninsular Malaysia were studied for presence of fungal endophyte. The objective of this study is to characterize fungal endophytes in the rhizome of four Diplazium species. The rhizome was surface sterilized and incubated to isolate fungal endophytes. Characterization of the colonies was performed by macroscopic morphological, microscopic identification, types of hyphae and mycelium, and spore structure. For isolation that produces spores, the structure of conidiophores and conidia were identified. From this study, four fungal have been isolated and determined as Aspergillus sp. (isolates AE 1), Aspergillus fumigatus (isolates AE 2), Aspergillus versicolor (isolates AE 3) and Verticillium sp. (isolates AE 4). The fungal isolates from this study were classified from the same family Moniliaceae.

  17. Adaptations in bacterial and fungal communities to termite fungiculture

    DEFF Research Database (Denmark)

    Otani, Saria

    in the bacterial and fungal communities. To do this, we used pyrosequencing, fluorescent in situ hybridisation, light and confocal microscopy, enzymatic assays, chemical extractions, in vitro assays, and feeding experiments in this thesis work to elucidate these predicted changes in fungus-growing termite...... in the proportion of fungal material provided to the cockroaches. However, gut microbiotas remained distinct from those of termites after Termitomyces-feeding, indicating that a fungal diet can play a role in structuring gut community composition, but at the same time exemplifies how original community compositions......, and possibly gut microenvironment constrain the magnitude of change. This thesis also characterises the fungus comb fungal communities (mycobiotas) in fungusgrowing termites, and shows that non-Termitomyces fungi were essentially absent in combs, and that Termitomyces fungal crops are maintained...

  18. Pyrosequencing assessment of rhizosphere fungal communities from a soybean field.

    Science.gov (United States)

    Sugiyama, Akifumi; Ueda, Yoshikatsu; Takase, Hisabumi; Yazaki, Kazufumi

    2014-10-01

    Soil fungal communities play essential roles in soil ecosystems, affecting plant growth and health. Rhizosphere bacterial communities have been shown to undergo dynamic changes during plant growth. This study utilized 454 pyrosequencing to analyze rhizosphere fungal communities during soybean growth. Members of the Ascomycota and Basiodiomycota dominated in all soils. There were no statistically significant changes at the phylum level among growth stages or between bulk and rhizosphere soils. In contrast, the relative abundance of small numbers of operational taxonomic units, 4 during growth and 28 between bulk and rhizosphere soils, differed significantly. Clustering analysis revealed that rhizosphere fungal communities were different from bulk fungal communities during growth stages of soybeans. Taken together, these results suggest that in contrast to rhizosphere bacterial communities, most constituents of rhizosphere fungal communities remained stable during soybean growth.

  19. The burden of serious fungal diseases in Russia.

    Science.gov (United States)

    Klimko, N; Kozlova, Y; Khostelidi, S; Shadrivova, O; Borzova, Y; Burygina, E; Vasilieva, N; Denning, D W

    2015-10-01

    The incidence and prevalence of fungal infections in Russia is unknown. We estimated the burden of fungal infections in Russia according to the methodology of the LIFE program (www.LIFE-worldwide.org). The total number of patients with serious and chronic mycoses in Russia in 2011 was three million. Most of these patients (2,607,494) had superficial fungal infections (recurrent vulvovaginal candidiasis, oral and oesophageal candidiasis with HIV infection and tinea capitis). Invasive and chronic fungal infections (invasive candidiasis, invasive and chronic aspergillosis, cryptococcal meningitis, mucormycosis and Pneumocystis pneumonia) affected 69,331 patients. The total number of adults with allergic bronchopulmonary aspergillosis and severe asthma with fungal sensitisation was 406,082. © 2015 Blackwell Verlag GmbH.

  20. Optical properties of arbuscular mycorrhizal fungal structures

    International Nuclear Information System (INIS)

    Perez, Adverdi; V-Hernandez, Alejandra; Rudamas, Carlos; Dreyer, Beatriz

    2008-01-01

    It was already reported by B. Dreyer at al. [1] that all fungal structures, both intra- and extra-radical fluoresced under blue light excitation regardless of their state (dead or alive). The source of the so called autofluorescence appears to be localized in the fungal cell wall. This supports the use of photoluminescence for the evaluation of AM colonization. However, the interpretation of these results is still in discussion [1-4]. In this work, arbuscular mycorrhizal spores were isolated from the rhizosphere of mango (Mangifera indica L.) plants by the method of wet sieving and decanting of Gerdemann and Nicolson [5] and studied by photoluminescence spectroscopy. Our experimental setup consists of an epifluorescence microscope (EM) coupled to a CCD-spectrometer through an arrangement of a home-made-telescope + fiber optic. This experimental setup allows the capture of images of the mycorrhizal structures (as usual in a standard epifluorescence microscope) combined with measurements of their corresponding emission bands. The preliminary results based on images obtained by standard EM do not clearly show that the emission is originated in the fungal cell walls as reported in Ref. 1. On the other hand, a very broad emission band in the visible part of the electromagnetic spectrum was observed in these spores by exciting at 450-490 nm and 300- 380 nm. We obtain a Full Width at Half Maximum (FWHM) of around 200 nm for this emission band whichis centered at 515 nm. This broad band seems to be composed of two narrower bands peaked around 494 and 547 nm and with FWHM of 50 nm and 150 nm, respectively. The profile of the observed emission band is in good agreement with the bands reported in Ref. 1 for vesicles, arbuscules and spores measured using the λ-Scan of a confocal laser scanning microscope. However, our results for spores show that the maxima of the narrower bands are shifted to higher energies in comparison to the corresponding bands observed in Ref. 1

  1. Specific recognition of fungal pathogens by plants

    International Nuclear Information System (INIS)

    Knogge, W.; Gierlich, A.; Max-Planck-Institute for Plant Breeding,; Van't Slot, K.A.E.; Papavoine, T.

    2001-01-01

    Full text: Induction of plant defence reactions and, hence, genotype-specific disease resistance results from the interaction of highly specific plant resistance (R) genes with matching pathogen avirulence (Avr) genes (gene-for-gene interactions). More than thirty R genes acting against different types of pathogens (viruses, bacteria, fungi, oomycetes, nematodes) have been isolated from various plants species. However, with few exceptions it remains to be shown how their products recognise the complementary Avr gene products. To date, Avr genes and their products have been characterised from only three fungal species. These include the NIP1 gene from Rhynchosporium secalis, the causal agent of barley leaf scald. It encodes a small, secreted protein, NIP1, that triggers defence reactions exclusively in barley cultivars expressing the R gene Rrs1. NIP1 also non-specifically stimulates the H + -ATPase activity in barley plasma membranes, suggesting that the host recognition system targets a putative fungal virulence factor. Virulent fungal strains lack the gene or carry an allele encoding a non-functional product. Four NIP1 iso-forms have been characterised; NIP1-I and NIP1-II although both elicitor-active display different levels of activity, whereas the isoforms NIP1-III and NIP1-IV are inactive. After establishing a heterologous expression system, the single amino acids specifying NIP1-III and NIP1-IV were integrated into the NIP1-I sequence and yielded the inactive mutant proteins NIP1-III* and NIP1-IV*. The elicitor-inactive isoforms were also unable to stimulate the H + -ATPase, suggesting that both functions of NIP1 are mediated by a single plant receptor. The 3D structure of NIP1-I has been elucidated by 1 H- and 15 N-NMR spectroscopy. Binding studies using 125 I-NIP1-I revealed a single class of high-affinity binding sites on membranes from both Rrs1- and rrs1-cultivars, suggesting that NIP1-binding is not sufficient for defence triggering and that an

  2. Selection of Infective Arbuscular Mycorrhizal Fungal Isolates for Field Inoculation

    Directory of Open Access Journals (Sweden)

    Elisa Pellegrino

    2010-09-01

    Full Text Available Arbuscular mycorrhizal (AM fungi play a key role in host plant growth and health, nutrient and water uptake, plant community diversity and dynamics. AM fungi differ in their symbiotic performance, which is the result of the interaction of two fungal characters, infectivity and efficiency. Infectivity is the ability of a fungal isolate to establish rapidly an extensive mycorrhizal symbiosis and is correlated with pre-symbiotic steps of fungal life cycle, such as spore germination and hyphal growth. Here, different AM fungal isolates were tested, with the aim of selecting infective endophytes for field inoculation. Greenhouse and microcosm experiments were performed in order to assess the ability of 12 AM fungal isolates to produce spores, colonize host roots and to perform initial steps of symbiosis establishment, such as spore germination and hyphal growth. AM fungal spore production and root colonization were significantly different among AM fungal isolates. Spore and sporocarp densities ranged from 0.8 to 7.4 and from 0.6 to 2.0 per gram of soil, respectively, whereas root colonization ranged from 2.9 to 72.2%. Percentage of spore or sporocarp germination ranged from 5.8 to 53.3% and hyphal length from 4.7 to 79.8 mm. The ordination analysis (Redundancy Analysis, RDA showed that environmental factors explained about 60% of the whole variance and their effect on fungal infectivity variables was significant (P = 0.002. The biplot clearly showed that variables which might be used to detect infective AM fungal isolates were hyphal length and root colonization. Such analysis may allow the detection of the best parameters to select efficient AM fungal isolates to be used in agriculture.

  3. Fungal Volatiles Can Act as Carbon Sources and Semiochemicals to Mediate Interspecific Interactions Among Bark Beetle-Associated Fungal Symbionts.

    Directory of Open Access Journals (Sweden)

    Jonathan A Cale

    Full Text Available Mountain pine beetle (Dendroctonus ponderosae has killed millions of hectares of pine forests in western North America. Beetle success is dependent upon a community of symbiotic fungi comprised of Grosmannia clavigera, Ophiostoma montium, and Leptographium longiclavatum. Factors regulating the dynamics of this community during pine infection are largely unknown. However, fungal volatile organic compounds (FVOCs help shape fungal interactions in model and agricultural systems and thus may be important drivers of interactions among bark beetle-associated fungi. We investigated whether FVOCs can mediate interspecific interactions among mountain pine beetle's fungal symbionts by affecting fungal growth and reproduction. Headspace volatiles were collected and identified to determine species-specific volatile profiles. Interspecific effects of volatiles on fungal growth and conidia production were assessed by pairing physically-separated fungal cultures grown either on a carbon-poor or -rich substrate, inside a shared-headspace environment. Fungal VOC profiles differed by species and influenced the growth and/or conidia production of the other species. Further, our results showed that FVOCs can be used as carbon sources for fungi developing on carbon-poor substrates. This is the first report demonstrating that FVOCs can drive interactions among bark beetle fungal symbionts, and thus are important factors in beetle attack success.

  4. Swainsonine biosynthesis genes in diverse symbiotic and pathogenic fungi

    Science.gov (United States)

    Swainsonine, a cytotoxic fungal alkaloid and a potential cancer therapy drug, is produced by the insect pathogen and plant symbiont, Metarhizium robertsii, the clover pathogen Slafractonia leguminicola, locoweed symbionts belonging to Alternaria sect. Undifilum, and a recently discovered morning glo...

  5. Analysis of the Sequences, Structures, and Functions of Product-Releasing Enzyme Domains in Fungal Polyketide Synthases

    Directory of Open Access Journals (Sweden)

    Lu Liu

    2017-09-01

    Full Text Available Product-releasing enzyme (PRE domains in fungal non-reducing polyketide synthases (NR-PKSs play a crucial role in catalysis and editing during polyketide biosynthesis, especially accelerating final biosynthetic reactions accompanied with product offloading. However, up to date, the systematic knowledge about PRE domains is deficient. In the present study, the relationships between sequences, structures, and functions of PRE domains were analyzed with 574 NR-PKSs of eight groups (I–VIII. It was found that the PRE domains in NR-PKSs could be mainly classified into three types, thioesterase (TE, reductase (R, and metallo-β-lactamase-type TE (MβL-TE. The widely distributed TE or TE-like domains were involved in NR-PKSs of groups I–IV, VI, and VIII. The R domains appeared in NR-PKSs of groups IV and VII, while the physically discrete MβL-TE domains were employed by most NR-PKSs of group V. The changes of catalytic sites and structural characteristics resulted in PRE functional differentiations. The phylogeny revealed that the evolution of TE domains was accompanied by complex functional divergence. The diverse sequence lengths of TE lid-loops affected substrate specificity with different chain lengths. The volume diversification of TE catalytic pockets contributed to catalytic mechanisms with functional differentiations. The above findings may help to understand the crucial catalysis of fungal aromatic polyketide biosyntheses and govern recombination of NR-PKSs to obtain unnatural target products.

  6. Aspergillus niger is a superior expression host for the production of bioactive fungal cyclodepsipeptides.

    Science.gov (United States)

    Boecker, Simon; Grätz, Stefan; Kerwat, Dennis; Adam, Lutz; Schirmer, David; Richter, Lennart; Schütze, Tabea; Petras, Daniel; Süssmuth, Roderich D; Meyer, Vera

    2018-01-01

    Fungal cyclodepsipeptides (CDPs) are non-ribosomally synthesized peptides produced by a variety of filamentous fungi and are of interest to the pharmaceutical industry due to their anticancer, antimicrobial and anthelmintic bioactivities. However, both chemical synthesis and isolation of CDPs from their natural producers are limited due to high costs and comparatively low yields. These challenges might be overcome by heterologous expression of the respective CDP-synthesizing genes in a suitable fungal host. The well-established industrial fungus Aspergillus niger was recently genetically reprogrammed to overproduce the cyclodepsipeptide enniatin B in g/L scale, suggesting that it can generally serve as a high production strain for natural products such as CDPs. In this study, we thus aimed to determine whether other CDPs such as beauvericin and bassianolide can be produced with high titres in A. niger , and whether the generated expression strains can be used to synthesize new-to-nature CDP derivatives. The beauvericin and bassianolide synthetases were expressed under control of the tuneable Tet-on promoter, and titres of about 350-600 mg/L for bassianolide and beauvericin were achieved when using optimized feeding conditions, respectively. These are the highest concentrations ever reported for both compounds, whether isolated from natural or heterologous expression systems. We also show that the newly established Tet-on based expression strains can be used to produce new-to-nature beauvericin derivatives by precursor directed biosynthesis, including the compounds 12-hydroxyvalerate-beauvericin and bromo-beauvericin. By feeding deuterated variants of one of the necessary precursors (d-hydroxyisovalerate), we were able to purify deuterated analogues of beauvericin and bassianolide from the respective A. niger expression strains. These deuterated compounds could potentially be used as internal standards in stable isotope dilution analyses to evaluate and quantify

  7. The Fungal Biome of the Oral Cavity.

    Science.gov (United States)

    Chandra, Jyotsna; Retuerto, Mauricio; Mukherjee, Pranab K; Ghannoum, Mahmoud

    2016-01-01

    Organisms residing in the oral cavity (oral microbiota) contribute to health and disease, and influence diseases like gingivitis, periodontitis, and oral candidiasis (the most common oral complication of HIV-infection). These organisms are also associated with cancer and other systemic diseases including upper respiratory infections. There is limited knowledge regarding how oral microbes interact together and influence the host immune system. Characterizing the oral microbial community (oral microbiota) in health and disease represents a critical step in gaining insight into various members of this community. While most of the studies characterizing oral microbiota have focused on bacterial community, there are few encouraging studies characterizing the oral mycobiome (the fungal component of the oral microbiota). Our group recently characterized the oral mycobiome in health and disease focusing on HIV. In this chapter we will describe the methods used by our group for characterization of the oral mycobiome.

  8. Modelling Fungal Fermentations for Enzyme Production

    DEFF Research Database (Denmark)

    Albæk, Mads Orla; Gernaey, Krist; Hansen, Morten S.

    We have developed a process model of fungal fed-batch fermentations for enzyme production. In these processes, oxygen transfer rate is limiting and controls the substrate feeding rate. The model has been shown to describe cultivations of both Aspergillus oryzae and Trichoderma reesei strains in 550......L stirred tank pilot plant reactors well. For each strain, 8 biological parameters are needed as well as a correlation of viscosity, as viscosity has a major influence on oxygen transfer. The parameters were measured averages of at least 9 batches for each strain. The model is successfully able...... to cover a wide range of process conditions (0.3-2 vvm of aeration, 0.2-10.0 kW/m3 of specific agitation power input, and 0.1-1.3 barg head space pressure). Uncertainty and sensitivity analysis have shown that the uncertainty of the model is mainly due to difficulties surrounding the estimation...

  9. 2. The Amsterdam Declaration on fungal nomenclature

    DEFF Research Database (Denmark)

    Hawksworth, David L.; Crous, Pedro W.; Redhead, Scott A.

    2011-01-01

    The Amsterdam Declaration on Fungal Nomenclature was agreed at an international symposium convened in Amsterdam on 19-20 April 2011 under the auspices of the International Commission on the Taxonomy of Fungi (ICTF). The purpose of the symposium was to address the issue of whether or how the current...... to advise on the problem. The Declaration recognizes the need for an orderly transition to a single-name nomenclatural system for all fungi, and to provide mechanisms to protect names that otherwise then become endangered. That is, meaning that priority should be given to the first described name, except...... where there is a younger name in general use when the first author to select a name of a pleomorphic monophyletic genus is to be followed, and suggests controversial cases are referred to a body, such as the ICTF, which will report to the Committee for Fungi. If appropriate, the ICTF could be mandated...

  10. Fungal endophytes: diversity and functional roles

    Science.gov (United States)

    Rodriguez, R.J.; White, J.F.; Arnold, A.E.; Redman, R.S.

    2009-01-01

    All plants in natural ecosystems appear to be symbiotic with fungal endophytes. This highly diverse group of fungi can have profound impacts on plant communities through increasing fitness by conferring abiotic and biotic stress tolerance, increasing biomass and decreasing water consumption, or decreasing fitness by altering resource allocation. Despite more than 100 yr of research resulting in thousands of journal articles, the ecological significance of these fungi remains poorly characterized. Historically, two endophytic groups (clavicipitaceous (C) and nonclavicipitaceous (NC)) have been discriminated based on phylogeny and life history traits. Here, we show that NC-endophytes represent three distinct functional groups based on host colonization and transmission, in planta biodiversity and fitness benefits conferred to hosts. Using this framework, we contrast the life histories, interactions with hosts and potential roles in plant ecophysiology of C- and NC-endophytes, and highlight several key questions for future work in endophyte biology.

  11. Fungal Phytotoxins in Sustainable Weed Management.

    Science.gov (United States)

    Vurro, Maurizio; Boari, Angela; Casella, Francesca; Zonno, Maria Chiara

    2018-01-01

    Fungal phytotoxins are natural secondary metabolites produced by plant pathogenic fungi during host-pathogen interactions. They have received considerable particular attention for elucidating disease etiology, and consequently to design strategies for disease control. Due to wide differences in their chemical structures, these toxic metabolites have different ecological and environmental roles and mechanisms of action. This review aims at summarizing the studies on the possible use of these metabolites as tools in biological and integrated weed management, e.g. as: novel and environmentally friendly herbicides; lead for novel compounds; sources of novel mechanisms of action. Moreover, the limiting factors for utilizing those metabolites in practice will also be briefly discussed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  12. Fungal infection risk groups among school children

    Directory of Open Access Journals (Sweden)

    Elżbieta Ejdas

    2014-08-01

    Full Text Available The aim of the study was to evaluate the relationship between ocurrence of fungi in children and living environment (city - countryside, sex, age, diet, undergone diseases therapy with antibiotics and exposure to hospital environment, and to indicate children potentially vulnerable to fungal infections. The material was consisted of swabs collected from the oral cavily, the throat and the nose of healthy children, aged 6-9 and 10-15, from both urban and rural environmens. Candida albicans, the basic aetiological factor in thc majority of mycoses recorded in humans, unquestionably prevailed in the group of the 13 speciec of yeast-like fungi and yeasts isolated. Records of C. glabrata and C. krusei increasing numbers of whose strains show resistance to basic antimycoties, as well as relatively frequent records of Trichosporon beigelii, Saccharomycopsis capsularis and Saccharomyces sp., fungi whose expansiveness and enzymatic activity have been growing, may be considered disconcerting. Vulnerability to fungal infection increases following anti-bacterial antibiotic therapy in the majority of subjects regardless season or age. This is particularly true primarily of the most stable ontocoenosis of the throat. Younger children, on the other hand, are the most vulnerable foUowing infection of the respiratory system. Fungi are likely to colonise the nose in this case. Children living in the countryside who had been ll immediately prior to the collection of the material constitute the highest risk group of the occurrence of fungi in any of the ontocoenoses studied. A greater number of positive inoculations were recorded in these children in comparison to the children from the city. It may be indicative of a more extensive spectrum of natural reservoirs of fungi and the vectors of their transmission in rural areas than those in the city, lower health hygiene and lower immunity or of a more common carriage of fungi among rural children.

  13. Soybean oil biosynthesis: role of diacylglycerol acyltransferases.

    Science.gov (United States)

    Li, Runzhi; Hatanaka, Tomoko; Yu, Keshun; Wu, Yongmei; Fukushige, Hirotada; Hildebrand, David

    2013-03-01

    Diacylglycerol acyltransferase (DGAT) catalyzes the acyl-CoA-dependent acylation of sn-1,2-diacylglycerol to form seed oil triacylglycerol (TAG). To understand the features of genes encoding soybean (Glycine max) DGATs and possible roles in soybean seed oil synthesis and accumulation, two full-length cDNAs encoding type 1 diacylglycerol acyltransferases (GmDGAT1A and GmDGAT1B) were cloned from developing soybean seeds. These coding sequences share identities of 94 % and 95 % in protein and DNA sequences. The genomic architectures of GmDGAT1A and GmDGAT1B both contain 15 introns and 16 exons. Differences in the lengths of the first exon and most of the introns were found between GmDGAT1A and GmDGAT1B genomic sequences. Furthermore, detailed in silico analysis revealed a third predicted DGAT1, GmDGAT1C. GmDGAT1A and GmDGAT1B were found to have similar activity levels and substrate specificities. Oleoyl-CoA and sn-1,2-diacylglycerol were preferred substrates over vernoloyl-CoA and sn-1,2-divernoloylglycerol. Both transcripts are much more abundant in developing seeds than in other tissues including leaves, stem, roots, and flowers. Both soybean DGAT1A and DGAT1B are highly expressed at developing seed stages of maximal TAG accumulation with DGAT1B showing highest expression at somewhat later stages than DGAT1A. DGAT1A and DGAT1B show expression profiles consistent with important roles in soybean seed oil biosynthesis and accumulation.

  14. Identification of Two Aflatrem Biosynthesis Gene Loci in Aspergillus flavus and Metabolic Engineering of Penicillium paxilli To Elucidate Their Function ▿

    Science.gov (United States)

    Nicholson, Matthew J.; Koulman, Albert; Monahan, Brendon J.; Pritchard, Beth L.; Payne, Gary A.; Scott, Barry

    2009-01-01

    Aflatrem is a potent tremorgenic toxin produced by the soil fungus Aspergillus flavus, and a member of a structurally diverse group of fungal secondary metabolites known as indole-diterpenes. Gene clusters for indole-diterpene biosynthesis have recently been described in several species of filamentous fungi. A search of Aspergillus complete genome sequence data identified putative aflatrem gene clusters in the genomes of A. flavus and Aspergillus oryzae. In both species the genes for aflatrem biosynthesis cluster at two discrete loci; the first, ATM1, is telomere proximal on chromosome 5 and contains a cluster of three genes, atmG, atmC, and atmM, and the second, ATM2, is telomere distal on chromosome 7 and contains five genes, atmD, atmQ, atmB, atmA, and atmP. Reverse transcriptase PCR in A. flavus demonstrated that aflatrem biosynthesis transcript levels increased with the onset of aflatrem production. Transfer of atmP and atmQ into Penicillium paxilli paxP and paxQ deletion mutants, known to accumulate paxilline intermediates paspaline and 13-desoxypaxilline, respectively, showed that AtmP is a functional homolog of PaxP and that AtmQ utilizes 13-desoxypaxilline as a substrate to synthesize aflatrem pathway-specific intermediates, paspalicine and paspalinine. We propose a scheme for aflatrem biosynthesis in A. flavus based on these reconstitution experiments in P. paxilli and identification of putative intermediates in wild-type cultures of A. flavus. PMID:19801473

  15. Accumulation of hydroxyproline-rich glycoprotein mRNAs in response to fungal elicitor and infection.

    Science.gov (United States)

    Showalter, A M; Bell, J N; Cramer, C L; Bailey, J A; Varner, J E; Lamb, C J

    1985-10-01

    Hydroxyproline-rich glycoproteins (HRGPs) are important structural components of plant cell walls and also accumulate in response to infection as an apparent defense mechanism. Accumulation of HRGP mRNA in biologically stressed bean (Phaseolus vulgaris L.) cells was monitored by blot hybridization with (32)P-labeled tomato genomic HRGP sequences. Elicitor treatment of suspension-cultured cells caused a marked increase in hybridizable HRGP mRNA. The response was less rapid but more prolonged than that observed for mRNAs encoding enzymes of phytoalexin biosynthesis. HRGP mRNA also accumulated during race:cultivar-specific interactions between bean hypocotyls and the partially biotrophic fungus Colletotrichum lindemuthianum, the causal agent of anthracnose. In an incompatible interaction (host resistant) there was an early increase in HRGP mRNA correlated with expression of hypersensitive resistance; whereas, in a compatible interaction (host susceptible), marked accumulation of HRGP mRNA occurred as a delayed response at the onset of lesion formation. In both interactions, mRNA accumulation was observed in uninfected cells distant from the site of fungal inoculation, indicating intercellular transmission of an elicitation signal.

  16. Exploring polyamine metabolism of Alternaria alternata to target new substances to control the fungal infection.

    Science.gov (United States)

    Estiarte, N; Crespo-Sempere, A; Marín, S; Sanchis, V; Ramos, A J

    2017-08-01

    Polyamines are essential for all living organisms as they are involved in several vital cell functions. The biosynthetic pathway of polyamines and its regulation is well established and, in this sense, the ornithine descarboxylase (ODC) enzyme acts as one of the controlling factors of the entire pathway. In this work we assessed the inhibition of the ODC with D, l-α-difluoromethylornithine (DFMO) on Alternaria alternata and we observed that fungal growth and mycotoxin production were reduced. This inhibition was not completely restored by the addition of exogenous putrescine. Actually, increasing concentrations of putrescine on the growth media negatively affected mycotoxin production, which was corroborated by the downregulation of pksJ and altR, both genes involved in mycotoxin biosynthesis. We also studied the polyamine metabolism of A. alternata with the goal of finding new targets that compromise its growth and its mycotoxin production capacity. In this sense, we tested two different polyamine analogs, AMXT-2455 and AMXT-3016, and we observed that they partially controlled A. alternata's viability in vitro and in vivo using tomato plants. Finding strategies to design new fungicide substances is becoming a matter of interest as resistance problems are emerging. Copyright © 2017. Published by Elsevier Ltd.

  17. Antimicrobial fungal endophytes from the botanical medicine goldenseal (Hydrastis canadensis).

    Science.gov (United States)

    Egan, Joseph M; Kaur, Amninder; Raja, Huzefa A; Kellogg, Joshua J; Oberlies, Nicholas H; Cech, Nadja B

    2016-09-01

    The potential of fungal endophytes to alter or contribute to plant chemistry and biology has been the topic of a great deal of recent interest. For plants that are used medicinally, it has been proposed that endophytes might play an important role in biological activity. With this study, we sought to identify antimicrobial fungal endophytes from the medicinal plant goldenseal ( Hydrastis canadensis L., Ranunculaceae), a plant used in traditional medicine to treat infection. A total of 23 fungal cultures were obtained from surface-sterilized samples of H. canadensis roots, leaves and seeds. Eleven secondary metabolites were isolated from these fungal endophytes, five of which had reported antimicrobial activity. Hydrastis canadensis plant material was then analyzed for the presence of fungal metabolites using liquid chromatography coupled to high resolving power mass spectrometry. The antimicrobial compound alternariol monomethyl ether was detected both as a metabolite of the fungal endophyte Alternaria spp. isolated from H. canadensis seeds, and as a component of an extract from the H. canadensis seed material. Notably, fungi of the Alternaria genus were isolated from three separate accessions of H. canadensis plant material collected in a time period spanning 5 years. The concentration of alternariol monomethyl ether (991 mg/kg in dry seed material) was in a similar range to that previously reported for metabolites of ecologically important fungal endophytes. The seed extracts themselves, however, did not possess antimicrobial activity.

  18. Clinical characteristics and distribution of pathogens in fungal keratitis

    Directory of Open Access Journals (Sweden)

    Tian Tian

    2016-01-01

    Full Text Available AIM:To investigate the clinical characteristics and distribution of pathogens in patients with fungal keratitis and to provide evidence for diagnosis and treatment of this disease.METHODS:The clinical data of 98 cases(98 eyeswith fungal keratitis from January 2012 to July 2015 in the First Affiliated Hospital of Yangtze University were retrospectively reviewed.RESULTS:The main cause for fungal keratitis was corneal injury by plants. The inappropriate use of contact lenses and glucocorticoids therapy were the next cause. Almost all of the patients had hyphae moss, pseudopodia, immune ring, and satellite signs. A few of patients had endothelial plaque and anterior chamber empyema. The majority pathogens of fungal keratitis was Fusarium spp(73.5%,followed by Aspergillus spp(13.2%,Candida spp(9.2%and others(4.1%.Sixty-five patients(65 eyestreated with 5% natamycin were cured. The condition of 15 patients was improved. Eighteen patients were invalid, in which 13 patients became better and 5 patients became worse after voriconazole was added into the therapy, leading to amniotic membrance cover in 3 patients and eyeball removal in 2 patients at last.CONCLUSION:Fusarium genus is the predominant pathogen for fungal keratitis in Jingzhou. Natamycin can be used as the preferred drug for the prevention and treatment for fungal keratitis. The clinicians should pay attention to the fungal keratitis, in order to early diagnosis and timely treatment.

  19. Impact of metal pollution on fungal diversity and community structures.

    Science.gov (United States)

    Op De Beeck, Michiel; Lievens, Bart; Busschaert, Pieter; Rineau, Francois; Smits, Mark; Vangronsveld, Jaco; Colpaert, Jan V

    2015-06-01

    The impact of metal pollution on plant communities has been studied extensively in the past, but little is known about the effects of metal pollution on fungal communities that occur in metal-polluted soils. Metal-tolerant ecotypes of the ectomycorrhizal fungus Suillus luteus are frequently found in pioneer pine forests in the Campine region in Belgium on metal-polluted soils. We hypothesized that metal pollution would play an important role in shaping below-ground fungal communities that occur in these soils and that Suillus luteus would be a dominant player. To test these hypotheses, the fungal communities in a young pine plantation in soil polluted with zinc, and cadmium were studied using 454 amplicon pyrosequencing. Results show that zinc, cadmium and soil organic matter content were strongly correlated with the fungal community composition, but no effects on fungal diversity were observed. As hypothesized, S. luteus was found to be a dominant member of the studied fungal communities. However, other dominant fungal species, such as Sistotrema sp., Wilcoxina mikolae and Cadophora finlandica were found as well. Their presence in metal-polluted sites is discussed. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  20. A novel model of invasive fungal rhinosinusitis in rats.

    Science.gov (United States)

    Zhang, Fang; An, Yunfang; Li, Zeqing; Zhao, Changqing

    2013-01-01

    Invasive fungal rhinosinusitis (IFRS) is a life-threatening inflammatory disease that affects immunocompromised patients, but animal models of the disease are scarce. This study aimed to develop an IFRS model in neutropenic rats. The model was established in three consecutive steps: unilateral nasal obstruction with Merocel sponges, followed by administration of cyclophosphamide (CPA), and, finally, nasal inoculation with Aspergillus fumigatus. Fifty healthy Wistar rats were randomly divided into five groups, with group I as the controls, group II undergoing unilateral nasal obstruction alone, group III undergoing nasal obstruction with fungal inoculation, group IV undergoing nasal obstruction with administration of CPA, and group V undergoing nasal obstruction with administration of CPA and fungal inoculation. Hematology, histology, and mycology investigations were performed. The changes in the rat absolute neutrophil counts (ANCs) were statistically different across the groups. The administration of CPA decreased the ANCs, whereas nasal obstruction with fungal inoculation increased the ANCs, and nasal obstruction did not change them. Histological examination of the rats in group V revealed the hyphal invasion of sinus mucosa and bone, thrombosis, and tissue infarction. No pathology indicative of IFRS was observed in the remaining groups. Positive rates of fungal culture in tissue homogenates from the maxillary sinus (62.5%) and lung (25%) were found in group V, whereas groups I, II, III, and IV showed no fungal culture in the homogenates. A rat IFRS model was successfully developed through nasal obstruction, CPA-induced neutropenia, and fungal inoculation. The disease model closely mimics the pathophysiology of anthropic IFRS.

  1. Pyrosequencing Reveals Fungal Communities in the Rhizosphere of Xinjiang Jujube

    Directory of Open Access Journals (Sweden)

    Peng Liu

    2015-01-01

    Full Text Available Fungi are important soil components as both decomposers and plant symbionts and play a major role in ecological and biogeochemical processes. However, little is known about the richness and structure of fungal communities. DNA sequencing technologies allow for the direct estimation of microbial community diversity, avoiding culture-based biases. We therefore used 454 pyrosequencing to investigate the fungal communities in the rhizosphere of Xinjiang jujube. We obtained no less than 40,488 internal transcribed spacer (ITS rDNA reads, the number of each sample was 6943, 6647, 6584, 6550, 6860, and 6904, and we used bioinformatics and multivariate statistics to analyze the results. The index of diversity showed greater richness in the rhizosphere fungal community of a 3-year-old jujube than in that of an 8-year-old jujube. Most operational taxonomic units belonged to Ascomycota, and taxonomic analyses identified Hypocreales as the dominant fungal order. Our results demonstrated that the fungal orders are present in different proportions in different sampling areas. Redundancy analysis (RDA revealed a significant correlation between soil properties and the abundance of fungal phyla. Our results indicated lower fungal diversity in the rhizosphere of Xinjiang jujube than that reported in other studies, and we hope our findings provide a reference for future research.

  2. Mites as selective fungal carriers in stored grain habitats.

    Science.gov (United States)

    Hubert, Jan; Stejskal, Václav; Kubátová, Alena; Munzbergová, Zuzana; Vánová, Marie; Zd'árková, Eva

    2003-01-01

    Mites are well documented as vectors of micromycetes in stored products. Since their vectoring capacity is low due to their small size, they can be serious vectors only where there is selective transfer of a high load of specific fungal species. Therefore the aim of our work was to find out whether the transfer of fungi is selective. Four kinds of stored seeds (wheat, poppy, lettuce, mustard) infested by storage mites were subjected to mycological analysis. We compared the spectrum of micromycete species isolated from different species of mites (Acarus siro, Lepidoglyphus destructor, Tyrophagus putrescentiae, Caloglyphus rhizoglyphoides and Cheyletus malaccensis) and various kinds of stored seeds. Fungi were separately isolated from (a) the surface of mites, (b) the mites' digestive tract (= faeces), and (c) stored seeds and were then cultivated and determined. The fungal transport via mites is selective. This conclusion is supported by (i) lower numbers of isolated fungal species from mites than from seeds; (ii) lower Shannon-Weaver diversity index in the fungal communities isolated from mites than from seeds; (iii) significant effect of mites/seeds as environmental variables on fungal presence in a redundancy analysis (RDA); (iv) differences in composition of isolated fungi between mite species shown by RDA. The results of our work support the hypothesis that mite-fungal interactions are dependent on mite species. The fungi attractive to mites seem to be dispersed more than others. The selectivity of fungal transport via mites enhances their pest importance.

  3. INCIDENCE OF ALLERGIC FUNGAL SINUSITIS AMONG PATIENTS WITH CHRONIC RHINOSINUSITIS

    Directory of Open Access Journals (Sweden)

    Vivek Gupta

    2017-09-01

    Full Text Available BACKGROUND This study aims to evaluate the incidence of allergic fungal sinusitis among patients with chronic rhinosinusitis. Chronic rhinosinusitis (CRS is a widely prevalent condition globally as well as in India. Fungal rhinosinusitis is classified into two subgroups: three invasive forms (acute necrotizing, chronic invasive, granulomatous invasive, and two noninvasive forms (fungal ball and allergic fungal. MATERIALS AND METHODS Patients attending the Department of ENT at Adesh institute of medical science & research, Bathinda (Punjab between Jan 2016 and Dec 2016 one year duration 82 cases were included in this retrospective analysis with features suggestive of chronic rhinosinusitis. Based on clinical, endoscopic and radiological parameters, 82 cases were diagnosed to have rhinosinusitis. In these cases, postoperatively after HPE examination, 16 cases were confirmed to have mycotic infection. RESULTS Out of 16 cases, In Allergic fungal rhino sinusitis(AFRS, Aspergillus flavus (A. flavus was the most common fungus isolated ten cases (71.42%.. In fungal ball, A. flavus was isolated in two cases (14.25% and Aspergillus niger (A. niger was isolated in two cases (14.25%. In invasive fungal rhinosinusitis (IFRS mucormycosis was isolated in two cases (12.5%. CONCLUSION The incidence of ARFS is about 12.2% of chronic rhinosinusitis. The commonest age group is second & third decade

  4. Assessment of relevant fungal species in clinical solid wastes.

    Science.gov (United States)

    Noman, Efaq Ali; Al-Gheethi, A A; Rahman, Nik Norulaini Nik Ab; Nagao, H; Ab Kadir, M O

    2016-10-01

    The study aimed to determine the fungal diversity in clinical waste samples from a healthcare facility in Penang Malaysia. Different fungi species were detected in 83.75 % of the 92 clinical waste samples that were screened from different sections of the healthcare facility. One hundred fifty fungal isolates comprising of 8 genera and 36 species were obtained. They were purified by using single spore isolation technique. Subsequently, the isolates were identified by phenotypic method based on morphological and culture characteristics on different culture media. Among all fungal isolates, Aspergillus spp. in section Nigri 10.2 %, Aspergillus niger 9.5 %, Aspergillus fumigatus 8.8 %, Penicillium. simplicissium 8 %, Aspergillus tubingensis 7.3 %, Aspergillus terreus var. terreus 6.6 %, Penicillium waksmanii 5.9 % and Curvularia lunata 6.5 % were the most frequent. Among five sections of the Wellness Centre, the clinical wastes collected from the diagnostic labs of haematology section had the highest numbers of fungal species (29 species). Glove wastes had the highest numbers of fungal species (19 species) among 17 types of clinical wastes screened. Among all fungal species, Aspergillus spp. exhibited higher growth at 37 °C than at 28 °C, indicating the potential of these opportunistic fungi to cause diseases in human. These results indicated the potential of hospital wastes as reservoirs for fungal species.

  5. Jasmonate-induced biosynthesis of andrographolide in Andrographis paniculata.

    Science.gov (United States)

    Sharma, Shiv Narayan; Jha, Zenu; Sinha, Rakesh Kumar; Geda, Arvind Kumar

    2015-02-01

    Andrographolide is a prominent secondary metabolite found in Andrographis paniculata that exhibits enormous pharmacological effects. In spite of immense value, the normal biosynthesis of andrographolide results in low amount of the metabolite. To induce the biosynthesis of andrographolide, we attempted elicitor-induced activation of andrographolide biosynthesis in cell cultures of A. paniculata. This was carried out by using methyl jasmonate (MeJA) as an elicitor. Among the various concentrations of MeJA tested at different time periods, 5 µM MeJA yielded 5.25 times more andrographolide content after 24 h of treatment. The accumulation of andrographolide was correlated with the expression level of known regulatory genes (hmgs, hmgr, dxs, dxr, isph and ggps) of mevalonic acid (MVA) and 2-C-methyl-d-erythritol-4-phosphate (MEP) pathways. These results established the involvement of MeJA in andrographolide biosynthesis by inducing the transcription of its biosynthetic pathways genes. The coordination of isph, ggps and hmgs expression highly influenced the andrographolide biosynthesis. © 2014 Scandinavian Plant Physiology Society.

  6. Periprosthetic fungal infection of a hip caused by Trichosporon inkin

    Directory of Open Access Journals (Sweden)

    Federico José Burgo, MD

    2018-03-01

    Full Text Available An immunocompromised patient with a history of multiple hip implant revisions extended courses of empiric antibiotic treatment, and a retained metallic rod in the femoral medullary canal was transferred for diagnostic studies and treatment. A high suspicion of fungal infection and utilization of extended and specific fungal cultures were the diagnostic keys for infection with Trichosporon inkin. The treatment consisted in a debridement surgery with the use of a functional spacer with cement supplemented with voriconazole and vancomycin plus a 6-month systemic treatment with voriconazole. After 2 years of follow-up, the patient is free of symptoms. Keywords: Hip arthroplasty, Periprosthetic fungal infection, Trichosporon inkin

  7. The Fungal Spores Survival Under the Low-Temperature Plasma

    Science.gov (United States)

    Soušková, Hana; Scholtz, V.; Julák, J.; Savická, D.

    This paper presents an experimental apparatus for the decontamination and sterilization of water suspension of fungal spores. The fungicidal effect of stabilized positive and negative corona discharges on four fungal species Aspergillus oryzae, Clacosporium sphaerospermum, Penicillium crustosum and Alternaria sp. was studied. Simultaneously, the slower growing of exposed fungal spores was observed. The obtained results are substantially different in comparison with those of the analogous experiments performed with bacteria. It may be concluded that fungi are more resistant to the low-temperature plasma.

  8. Fungal NRPS-dependent siderophores: From function to prediction

    DEFF Research Database (Denmark)

    Sørensen, Jens Laurids; Knudsen, Michael; Hansen, Frederik Teilfeldt

    2014-01-01

    discuss the function of siderophores in relation to fungal iron uptake mechanisms and their importance for coexistence with host organisms. The chemical nature of the major groups of siderophores and their regulation is described along with the function and architecture of the large multi-domain enzymes...... responsible for siderophore synthesis, namely the non-ribosomal peptide synthetases (NRPSs). Finally, we present the most recent advances in our understanding of the structural biology of fungal NRPSs and discuss opportunities for the development of a fungal NRPS prediction server...

  9. Citrate coated silver nanoparticles with modulatory effects on aflatoxin biosynthesis in Aspergillus parasiticus

    Science.gov (United States)

    Mitra, Chandrani

    The manufacture and usage of silver nanoparticles has drastically increased in recent years (Fabrega et al. 2011a). Hence, the levels of nanoparticles released into the environment through various routes have measurably increased and therefore are concern to the environment and to public health (Panyala, Pena-Mendez and Havel 2008). Previous studies have shown that silver nanoparticles are toxic to various organisms such as bacteria (Kim et al. 2007), fungi (Kim et al. 2008), aquatic plants (He, Dorantes-Aranda and Waite 2012a), arthropods (Khan et al. 2015), and mammalian cells (Asharani, Hande and Valiyaveettil 2009) etc. Most of the toxicity studies are carried out using higher concentrations or lethal doses of silver nanoparticles. However, there is no information available on how the fungal community reacts to the silver nanoparticles at nontoxic concentrations. In this study, we have investigated the effect of citrate coated silver nanoparticles (AgNp-cit) at a size of 20nm on Aspergillus parasiticus, a popular plant pathogen and well-studied model for secondary metabolism (natural product synthesis). A. parasiticus produces 4 major types of aflatoxins. Among other aflatoxins, aflatoxin B1 is considered to be one of most potent naturally occurring liver carcinogen, and is associated with an estimated 155,000 liver cancer cases globally (Liu and Wu 2010); therefore, contaminated food and feed are a significant risk factor for liver cancer in humans and animals (CAST 2003; Liu and Wu 2010). In this study, we have demonstrated the uptake of AgNp-cit (20nm) by A. parasiticus cells from the growth medium using a time course ICP-OES experiment. It was observed that the uptake of AgNp-cit had no effect on fungal growth and significantly decreased intracellular oxidative stress. It also down-regulated aflatoxin biosynthesis at the level of gene expression of aflatoxin pathway genes and the global regulatory genes of secondary metabolism. We also observed that the

  10. Regulation of anthocyanin biosynthesis in peach fruits.

    Science.gov (United States)

    Rahim, Md Abdur; Busatto, Nicola; Trainotti, Livio

    2014-11-01

    MYB10.1 and MYB10.3, with bHLH3, are the likely regulators of anthocyanin biosynthesis in peach fruit. MYB10.1/2/3 forms a cluster on the same genomic fragment where the Anther color ( Ag ) trait is located. Anthocyanins are bioactive compounds responsible for the pigmentation of many plant parts such as leaves, flowers, fruits and roots, and have potential benefits to human health. In peach [Prunus persica (L.) Batsch], peel color is a key determinant for fruit quality and is regulated by flavonoids including anthocyanins. The R2R3 MYB transcription factors (TFs) control the expression of anthocyanin biosynthetic genes with the help of co-activators belonging to the basic-helix-loop-helix (bHLH) and WD40 repeat families. In the peach genome six MYB10-like and three bHLH-like TFs were identified as candidates to be the regulators of the anthocyanin accumulation, which, in yellow flesh fruits, is highest in the peel, abundant in the part of the mesocarp surrounding the stone and lowest in the mesocarp. The expression of MYB10.1 and MYB10.3 correlates with anthocyanin levels of different peach parts. They also have positive correlation with the expression of key structural genes of the anthocyanin pathway, such as CHS, F3H, and UFGT. Functions of peach MYB10s were tested in tobacco and shown to activate key genes in the anthocyanin pathway when bHLHs were co-expressed as partners. Overexpression of MYB10.1/bHLH3 and MYB10.3/bHLH3 activated anthocyanin production by up-regulating NtCHS, NtDFR and NtUFGT while other combinations were not, or much less, effective. As three MYB10 genes are localized in a genomic region where the Ag trait, responsible for anther pigmentation, is localized, it is proposed they are key determinant to introduce new peach cultivars with higher antioxidant level and pigmented fruit.

  11. NAD+ biosynthesis, aging, and disease [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Sean Johnson

    2018-02-01

    Full Text Available Nicotinamide adenine dinucleotide (NAD+ biosynthesis and its regulation have recently been attracting markedly increasing interest. Aging is marked by a systemic decrease in NAD+ across multiple tissues. The dysfunction of NAD+ biosynthesis plays a critical role in the pathophysiologies of multiple diseases, including age-associated metabolic disorders, neurodegenerative diseases, and mental disorders. As downstream effectors, NAD+-dependent enzymes, such as sirtuins, are involved in the progression of such disorders. These recent studies implicate NAD+ biosynthesis as a potential target for preventing and treating age-associated diseases. Indeed, new studies have demonstrated the therapeutic potential of supplementing NAD+ intermediates, such as nicotinamide mononucleotide and nicotinamide riboside, providing a proof of concept for the development of an effective anti-aging intervention.

  12. Zincophorin – biosynthesis in Streptomyces griseus and antibiotic properties

    Directory of Open Access Journals (Sweden)

    Walther, Elisabeth

    2016-11-01

    Full Text Available Zincophorin is a polyketide antibiotic that possesses potent activity against Gram-positive bacteria, including human pathogens. While a number of total syntheses of this highly functionalized natural product were reported since its initial discovery, the genetic basis for the biosynthesis of zincophorin has remained unclear. In this study, the co-linearity inherent to polyketide pathways was used to identify the zincophorin biosynthesis gene cluster in the genome of the natural producer HKI 0741. Interestingly, the same locus is fully conserved in the streptomycin-producing actinomycete IFO 13350, suggesting that the latter bacterium is also capable of zincophorin biosynthesis. Biological profiling of zincophorin revealed a dose-dependent inhibition of the Gram-positive bacterium . The antibacterial effect, however, is accompanied by cytotoxicity. Antibiotic and cytotoxic activities were completely abolished upon esterification of the carboxylic acid group in zincophorin.

  13. Purine biosynthesis de novo by lymphocytes in gout

    International Nuclear Information System (INIS)

    Kamoun, P.; Chanard, J.; Brami, M.; Funck-Brentano, J.L.

    1978-01-01

    A method of measurement in vitro of purine biosynthesis de novo in human circulating blood lymphocytes is proposed. The rate of early reactions of purine biosynthesis de novo was determined by the incorporation of [ 14 C]formate into N-formyl glycinamide ribonucleotide when the subsequent reactions of the metabolic pathway were completely inhibited by the antibiotic azaserine. Synthesis of 14 C-labelled N-formyl glycinamide ribonucleotide by lymphocytes was measured in healthy control subjects and patients with primary gout or hyperuricaemia secondary to renal failure, with or without allopurinol therapy. The average synthesis was higher in gouty patients without therapy than in control subjects, but the values contained overlap the normal range. In secondary hyperuricaemia the synthesis was at same value as in control subjects. These results are in agreement with the inconstant acceleration of purine biosynthesis de novo in gouty patients as seen by others with measurement of [ 14 C]glycine incorporation into urinary uric acid. (author)

  14. Methoxypyrazines biosynthesis and metabolism in grape: A review.

    Science.gov (United States)

    Lei, Yujuan; Xie, Sha; Guan, Xueqiang; Song, Changzheng; Zhang, Zhenwen; Meng, Jiangfei

    2018-04-15

    This review summarizes research on the discovery, biosynthesis, accumulation, transport, and metabolism of 3-alkyl-2-methoxypyrazines (MPs) in grape. The MPs are a family of potent volatile compounds distributed throughout biological kingdoms. These compounds impart herbaceous/green/vegetal sensory attributes to certain varieties of wine. Generally, high levels of MPs in wine are derived mainly from the corresponding grapes. Although two pathways for MPs biosynthesis have been proposed, only the final step and the enzymes that catalyze it has been confirmed in grape, and the metabolic intermediates and key enzymes involved in other steps are still unknown. The limited understanding of MPs metabolism has restricted research on these compounds, and some empirical results cannot be explained by the current knowledge of MPs metabolism. This review provides insights into research on MPs biosynthesis and metabolism, and proposes directions for further research on this important class of flavour/odour compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Genes encoding enzymes of the lignin biosynthesis pathway in Eucalyptus

    Directory of Open Access Journals (Sweden)

    Ricardo Harakava

    2005-01-01

    Full Text Available Eucalyptus ESTs libraries were screened for genes involved in lignin biosynthesis. This search was performed under the perspective of recent revisions on the monolignols biosynthetic pathway. Eucalyptus orthologues of all genes of the phenylpropanoid pathway leading to lignin biosynthesis reported in other plant species were identified. A library made with mRNAs extracted from wood was enriched for genes involved in lignin biosynthesis and allowed to infer the isoforms of each gene family that play a major role in wood lignin formation. Analysis of the wood library suggests that, besides the enzymes of the phenylpropanoids pathway, chitinases, laccases, and dirigent proteins are also important for lignification. Colocalization of several enzymes on the endoplasmic reticulum membrane, as predicted by amino acid sequence analysis, supports the existence of metabolic channeling in the phenylpropanoid pathway. This study establishes a framework for future investigations on gene expression level, protein expression and enzymatic assays, sequence polymorphisms, and genetic engineering.

  16. Recent advances in combinatorial biosynthesis for drug discovery

    Directory of Open Access Journals (Sweden)

    Sun H

    2015-02-01

    Full Text Available Huihua Sun,1,* Zihe Liu,1,* Huimin Zhao,1,2 Ee Lui Ang1 1Metabolic Engineering Research Laboratory, Institute of Chemical and Engineering Sciences, Agency for Science, Technology and Research, Singapore; 2Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA *These authors contributed equally to this work Abstract: Because of extraordinary structural diversity and broad biological activities, natural products have played a significant role in drug discovery. These therapeutically important secondary metabolites are assembled and modified by dedicated biosynthetic pathways in their host living organisms. Traditionally, chemists have attempted to synthesize natural product analogs that are important sources of new drugs. However, the extraordinary structural complexity of natural products sometimes makes it challenging for traditional chemical synthesis, which usually involves multiple steps, harsh conditions, toxic organic solvents, and byproduct wastes. In contrast, combinatorial biosynthesis exploits substrate promiscuity and employs engineered enzymes and pathways to produce novel “unnatural” natural products, substantially expanding the structural diversity of natural products with potential pharmaceutical value. Thus, combinatorial biosynthesis provides an environmentally friendly way to produce natural product analogs. Efficient expression of the combinatorial biosynthetic pathway in genetically tractable heterologous hosts can increase the titer of the compound, eventually resulting in less expensive drugs. In this review, we will discuss three major strategies for combinatorial biosynthesis: 1 precursor-directed biosynthesis; 2 enzyme-level modification, which includes swapping of the entire domains, modules and subunits, site-specific mutagenesis, and directed evolution; 3 pathway-level recombination. Recent examples of combinatorial biosynthesis employing these

  17. Final Report on Regulation of Guaiacyl and Syringyl Monolignol Biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Vincent L. Chiang

    2006-03-09

    The focus of this research is to understand syringyl monolignol biosynthesis that leads to the formation of syringyl lignin, a type of lignin that can be easily removed during biomass conversion. We have achieved the three originally proposed goals for this project. (1) SAD and CAD genes (enzyme catalytic and kinetic properties) and their functional relevance to CAld5H/AldOMT pathway, (2) spatiotemporal expression patterns of Cald5H, AldOMT, SAD and CAD genes, and (3) functions of CAld5H, AldOMT, and SAD genes in vivo using transgenic aspen. Furthermore, we also found that microRNA might be involved in the upstream regulatory network of lignin biosynthesis and wood formation. The achievements are as below. (1) Based on biochemical and molecular studies, we discovered a novel syringyl-specific alcohol dehydrogenase (SAD) involved in monolignol biosynthesis in angiosperm trees. Through CAld5H/OMT/SAD mediation, syringyl monolignol biosynthesis branches out from guaiacyl pathway at coniferaldehyde; (2) The function of CAld5H gene in this syringyl monolignol biosynthesis pathway also was confirmed in vivo in transgenic Populus; (3) The proposed major monolignol biosynthesis pathways were further supported by the involving biochemical functions of CCR based on a detailed kinetic study; (4) Gene promoter activity analysis also supported the cell-type specific expression of SAD and CAD genes in xylem tissue, consistent with the cell-specific locations of SAD and CAD proteins and with the proposed pathways; (5) We have developed a novel small interfering RNA (siRNA)-mediated stable gene-silencing system in transgenic plants; (6) Using the siRNA and P. trichocarpa transformation/regeneration systems we are currently producing transgenic P. trichocarpa to investigate the interactive functions of CAD and SAD in regulating guaiacyl and syringyl lignin biosynthesis; (7) We have cloned for the first time from a tree species, P. trichocarpa, small regulatory RNAs termed micro

  18. Pseudopterosin Biosynthesis: Aromatization of the Diterpene Cyclase Product, Elisabethatriene

    Directory of Open Access Journals (Sweden)

    Amber C. Kohl

    2003-11-01

    Full Text Available Abstract: Putative precursors in pseudopterosin biosynthesis, the hydrocarbons isoelisabethatriene (10 and erogorgiaene (11, have been identified from an extract of Pseudopterogorgia elisabethae collected in the Florida Keys. Biosynthetic experiments designed to test the utilization of these compounds in pseudopterosin production revealed that erogorgiaene is transformed to pseudopterosins A-D. Together with our previous data, it is now apparent that early steps in pseudopterosin biosynthesis involve the cyclization of geranylgeranyl diphosphate to elisabethatriene followed by the dehydrogenation and aromatization to erogorgiaene.

  19. In vitro biosynthesis of unnatural enterocin and wailupemycin polyketides.

    Science.gov (United States)

    Kalaitzis, John A; Cheng, Qian; Thomas, Paul M; Kelleher, Neil L; Moore, Bradley S

    2009-03-27

    Nature has evolved finely tuned strategies to synthesize rare and complex natural products such as the enterocin family of polyketides from the marine bacterium Streptomyces maritimus. Herein we report the directed ex vivo multienzyme syntheses of 24 unnatural 5-deoxyenterocin and wailupemycin F and G analogues, 18 of which are new. We have generated molecular diversity by priming the enterocin biosynthesis enzymes with unnatural substrates and have illustrated further the uniqueness of this type II polyketide synthase by way of exploiting its unusual starter unit biosynthesis pathways.

  20. Sequential enzymatic epoxidation involved in polyether lasalocid biosynthesis.

    Science.gov (United States)

    Minami, Atsushi; Shimaya, Mayu; Suzuki, Gaku; Migita, Akira; Shinde, Sandip S; Sato, Kyohei; Watanabe, Kenji; Tamura, Tomohiro; Oguri, Hiroki; Oikawa, Hideaki

    2012-05-02

    Enantioselective epoxidation followed by regioselective epoxide opening reaction are the key processes in construction of the polyether skeleton. Recent genetic analysis of ionophore polyether biosynthetic gene clusters suggested that flavin-containing monooxygenases (FMOs) could be involved in the oxidation steps. In vivo and in vitro analyses of Lsd18, an FMO involved in the biosynthesis of polyether lasalocid, using simple olefin or truncated diene of a putative substrate as substrate mimics demonstrated that enantioselective epoxidation affords natural type mono- or bis-epoxide in a stepwise manner. These findings allow us to figure out enzymatic polyether construction in lasalocid biosynthesis. © 2012 American Chemical Society

  1. Topical problems in the biosynthesis of red blood pigment

    International Nuclear Information System (INIS)

    Franck, B.

    1982-01-01

    Uroporphyrinogen III plays a key role in the biosynthesis of heme, the red pigment of blood. In vivo studies with specifically 14 C- and 3 H-labeled precursors have revealed that the formation of uroporphyrinogen III in the organism follows several primary and subsidiary pathways. Model experiments on the pattern of biosynthesis have led to simple and effective methods of synthesizing uroporphyrin analogs and have shwon that their production is strongly favored thermodynamically, The biologically important porphyrins thus available permit a mechanistic explanantion of the light-induced dermatoses in porphyria diseases and suggest promising medical applications in diagnosis and therapy. (orig.)

  2. Structure, Biosynthesis, and Occurrence of Bacterial Pyrrolizidine Alkaloids.

    Science.gov (United States)

    Schimming, Olivia; Challinor, Victoria L; Tobias, Nicholas J; Adihou, Hélène; Grün, Peter; Pöschel, Laura; Richter, Christian; Schwalbe, Harald; Bode, Helge B

    2015-10-19

    Pyrrolizidine alkaloids (PAs) are widespread plant natural products with potent toxicity and bioactivity. Herein, the identification of bacterial PAs from entomopathogenic bacteria using differential analysis by 2D NMR spectroscopy (DANS) and mass spectrometry is described. Their biosynthesis was elucidated to involve a non-ribosomal peptide synthetase. The occurrence of these biosynthesis gene clusters in Gram-negative and Gram-positive bacteria indicates an important biological function in bacteria. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Modified atmospheric conditions controlling fungal growth on cheese

    DEFF Research Database (Denmark)

    Nielsen, Per Væggemose

    1997-01-01

    Effective control of fungal growth on cheese under storage conditions is of great concern for the dairy industry. Therefore we designed a research project together with the Danish dairy industry on modelling fungal growth on cheese as affected by the combined effect of storage conditions (O2 and CO......2 level, relative humidity and temperature) and the composition of the cheese. All fungal species commonly found on cheese, starter cultures as well as contaminants, were examined.The most important factors influencing fungal growth are temperature, water activity of the medium and the carbon...... a competitive advantage over other fungi in moist conditions with high carbon dioxide levels, such as inside a roquefort cheese or in gas tight grain storage. The key to success in food packaging is to recognise the food ecosystem, as it enables us to identify which micro...

  4. Physico-chemical and microbiological profile of bacterial and fungal ...

    African Journals Online (AJOL)

    EJIRO

    discharge respectively. Several bacterial and fungal genera were isolated from the River water samples. ...... global climate change, Potential impacts on inland freshwater and ... India: Discharge scenarios and case for participatory ecosystem.

  5. Fungal isolates and their toxicity from different ecosystems in ...

    African Journals Online (AJOL)

    ONOS

    2010-08-23

    Aug 23, 2010 ... fungal species behave unexpectedly in different ecosystems. That is why the main ... All the isolates from marine environment were non toxic to brine ... by animals or humans. Severe health problems and death have occurred.

  6. Vertical distribution of ectomycorrhizal fungal taxa in a podzol profile

    NARCIS (Netherlands)

    Rosling, A.; Landeweert, R.; Lindahl, B.D.; Larsson, K.H.; Kuyper, T.W.; Taylor, A.F.S.; Finlay, R.F.

    2003-01-01

    Studies of ectomycorrhizal fungal communities in forest soils are usually restricted to the uppermost organic horizons. Boreal forest podzols are highly stratified and little is known about the vertical distribution of ectomycorrhizal communities in the underlying mineral horizons. Ectomycorrhizal

  7. Evolution and genome architecture in fungal plant pathogens.

    Science.gov (United States)

    Möller, Mareike; Stukenbrock, Eva H

    2017-12-01

    The fungal kingdom comprises some of the most devastating plant pathogens. Sequencing the genomes of fungal pathogens has shown a remarkable variability in genome size and architecture. Population genomic data enable us to understand the mechanisms and the history of changes in genome size and adaptive evolution in plant pathogens. Although transposable elements predominantly have negative effects on their host, fungal pathogens provide prominent examples of advantageous associations between rapidly evolving transposable elements and virulence genes that cause variation in virulence phenotypes. By providing homogeneous environments at large regional scales, managed ecosystems, such as modern agriculture, can be conducive for the rapid evolution and dispersal of pathogens. In this Review, we summarize key examples from fungal plant pathogen genomics and discuss evolutionary processes in pathogenic fungi in the context of molecular evolution, population genomics and agriculture.

  8. Fungal biogeography. Global diversity and geography of soil fungi.

    Science.gov (United States)

    Tedersoo, Leho; Bahram, Mohammad; Põlme, Sergei; Kõljalg, Urmas; Yorou, Nourou S; Wijesundera, Ravi; Villarreal Ruiz, Luis; Vasco-Palacios, Aída M; Thu, Pham Quang; Suija, Ave; Smith, Matthew E; Sharp, Cathy; Saluveer, Erki; Saitta, Alessandro; Rosas, Miguel; Riit, Taavi; Ratkowsky, David; Pritsch, Karin; Põldmaa, Kadri; Piepenbring, Meike; Phosri, Cherdchai; Peterson, Marko; Parts, Kaarin; Pärtel, Kadri; Otsing, Eveli; Nouhra, Eduardo; Njouonkou, André L; Nilsson, R Henrik; Morgado, Luis N; Mayor, Jordan; May, Tom W; Majuakim, Luiza; Lodge, D Jean; Lee, Su See; Larsson, Karl-Henrik; Kohout, Petr; Hosaka, Kentaro; Hiiesalu, Indrek; Henkel, Terry W; Harend, Helery; Guo, Liang-dong; Greslebin, Alina; Grelet, Gwen; Geml, Jozsef; Gates, Genevieve; Dunstan, William; Dunk, Chris; Drenkhan, Rein; Dearnaley, John; De Kesel, André; Dang, Tan; Chen, Xin; Buegger, Franz; Brearley, Francis Q; Bonito, Gregory; Anslan, Sten; Abell, Sandra; Abarenkov, Kessy

    2014-11-28

    Fungi play major roles in ecosystem processes, but the determinants of fungal diversity and biogeographic patterns remain poorly understood. Using DNA metabarcoding data from hundreds of globally distributed soil samples, we demonstrate that fungal richness is decoupled from plant diversity. The plant-to-fungus richness ratio declines exponentially toward the poles. Climatic factors, followed by edaphic and spatial variables, constitute the best predictors of fungal richness and community composition at the global scale. Fungi show similar latitudinal diversity gradients to other organisms, with several notable exceptions. These findings advance our understanding of global fungal diversity patterns and permit integration of fungi into a general macroecological framework. Copyright © 2014, American Association for the Advancement of Science.

  9. Scientists discover how deadly fungal microbes enter host cells

    OpenAIRE

    Whyte, Barry James

    2010-01-01

    A research team led by scientists at the Virginia Bioinformatics Institute at Virginia Tech has discovered a fundamental entry mechanism that allows dangerous fungal microbes to infect plants and cause disease.

  10. Antimycobacterial and cytotoxic activities of extracts from fungal ...

    African Journals Online (AJOL)

    Antimycobacterial and cytotoxic activities of extracts from fungal isolates of Lake Magadi. Keno David Kowanga, Joan John Eliona Munissi, Rose Masalu, Stephen Samwel Nyandoro, Pax Masimba, Erastus Gatebe ...

  11. Fungal burden exposure assessment in podiatry clinics from Ireland.

    Science.gov (United States)

    Viegas, Carla; Coggins, Ann Marie; Faria, Tiago; Caetano, Liliana Aranha; Gomes, Anita Quintal; Sabino, Raquel; Verissimo, Cristina; Roberts, Nigel; Watterson, David; MacGilchrist, Claire; Fleming, Gerard T A

    2018-03-26

    Fungi are amongst the bioaerosols of most importance, as indicated by the growing interest in this field of research. The aim was to characterize the exposure to fungal burden in podiatry clinics using culture-based and molecular methods. Airborne fungi were collected using an impaction air sampler and surface samples were also performed. Fourteen air samples were collected for direct detection of fungal DNA from filamentous fungi and dermatophytes. Overall, 63.6 % of the evening samples and 46 % of the morning samples surpassed the threshold values (150 CFU/m 3 ). Molecular detection, by real time PCR, of the target fungal species/strains (Aspergillus and Stachybotrys species) was negative for all samples collected. Trichophyton rubrum was detected by PCR analysis in one DNA sample collected on day six. Results suggest the use of both culture-based and molecular methodologies are desirable for a complete evaluation of fungal burden in this particular health care setting.

  12. Analysis of computed tomography features of fungal sinusitis and ...

    African Journals Online (AJOL)

    CT) features of fungal sinusitis and to correlate them with nasal endoscopy and histopathological findings. Materials and Methods: Our study included 16 patients of either sex and any age group who presented in the otorhinolaryngology clinic at ...

  13. Sinonasal Fungal Infections and Complications: A Pictorial Review

    Directory of Open Access Journals (Sweden)

    Jose Gavito-Higuera

    2016-01-01

    Full Text Available Fungal infections of the nose and paranasal sinuses can be categorized into invasive and non-invasive forms. The clinical presentation and course of the disease is primarily determined by the immune status of the host and can range from harmless or subtle presentations to life threatening complications. Invasive fungal infections are categorized into acute, chronic or chronic granulomatous entities. Immunocompromised patients with poorly controlled diabetes mellitus, HIV and patients receiving chemotherapy or chronic oral corticosteroids are mostly affected. Mycetoma and Allergic Fungal Rhinosinusitis are considered non-invasive forms. Computer tomography is the gold-standard in sinonasal imaging and is complimented by Magnetic resonance imaging (MRI as it is superior in the evaluation of intraorbital and intracranial extensions. The knowledge and identification of the characteristic imaging patterns in invasive - and non- invasive fungal rhinosinusitis is crucial and the radiologist plays an important role in refining the diagnosis to prevent a possible fatal outcome.

  14. 7 CFR 201.58d - Fungal endophyte test.

    Science.gov (United States)

    2010-01-01

    ... staining solution. Slightly crush the seeds. Use caution to prevent carryover hyphae of fungal endophyte... compound microscope at 100-400x magnification, scoring a seed as positive if any identifiable hyphae are...

  15. Fungal infections in animals: a patchwork of different situations

    DEFF Research Database (Denmark)

    Seyedmousavi, Seyedmojtaba; Bosco, Sandra De M G; De Hoog, Sybren

    2018-01-01

    The importance of fungal infections in both human and animals has increased over the last decades. This article represents an overview of the different categories of fungal infections that can be encountered in animals originating from environmental sources without transmission to humans....... In addition, the endemic infections with indirect transmission from the environment, the zoophilic fungal pathogens with near-direct transmission, the zoonotic fungi that can be directly transmitted from animals to humans, mycotoxicoses and antifungal resistance in animals will also be discussed....... Opportunistic mycoses are responsible for a wide range of diseases from localized infections to fatal disseminated diseases, such as aspergillosis, mucormycosis, candidiasis, cryptococcosis and infections caused by melanized fungi. The amphibian fungal disease chytridiomycosis and the Bat White-nose syndrome...

  16. [Biosorption of heavy metals in fluoritum decoction by fungal mycelium].

    Science.gov (United States)

    Cui, Pei-wu; Hu, Wei; Hu, Ya-qiang; Tan, Zhao-yang

    2014-09-01

    To explore the biosorption technology of heavy metals in Fluoritum decoction by fungal mycelium. Four factors including fungal mycelium amount, adsorption time, pH value and temperature were employed to estimate the fungal biomass adsorption conditions for removing the heavy metals in Fluoritum decoction. Then an orthogonal experimental design was taken to optimize the biosorption process, and the removal efficiency was also evaluated. Under the optimized conditions of 1.0 g/50 mL Fluoritum decoction, 3 hours adsorption time, pH 5.0 and 40 degrees C, a result of 70.12% heavy metals removal rate was accomplished with 35.99% calcium ion loss. The study indicates that removing of heavy metals in Fluoritum decoction through fungal mycelium is feasible, and the experiment results can also provide a basis for further research on biosorption of heavy metals in traditional Chinese medicine

  17. Nutrients, phytochemicals, fungal flora and aflatoxin in fresh and ...

    African Journals Online (AJOL)

    Dr Ob

    In this study, the effect of salting on the pH, phytochemicals, fungal flora and nutrient composition of. Vernonia .... Vitamin C, β-carotene, carbohydrates, protein and moisture: ..... on rats fed a high cholesterol diet. ... male New Zealand rabbits.

  18. Sugarcane Bagasse: A Potential Medium for Fungal Cultures

    OpenAIRE

    Arushdeep Sidana; Umar Farooq

    2014-01-01

    Worldwide, sugarcane industries produce tons of sugarcane bagasse as residual/waste material. This residual material is rich in complex lignocellulosic substances and may be used as a low cost carbon and energy source for the growth of fungal species. The present work was aimed at designing a sugarcane waste-based medium as a substitute for expensive commercial media for growing fungal cultures. Eight species of fungi, namely, Aspergillus niger, Candida albicans, Saccharomyces cerevisiae, Fus...

  19. Influence of storage on fungal infestation in spices

    International Nuclear Information System (INIS)

    Akhtar, T.; Sattar, A.; Khan, I.

    1988-01-01

    The present work was carried out to study the influence of storage and gamma radiation on fungal control in spices. The spices were irradiated with 5.0, 7.5 and 10.0 KGy and stored under ambient conditions for 12 months. Fungal infestation decreased to undetectable levels upon irradiation of these spices especially at higher doses and increased with advanced storage period both the irradiated and unirradiated samples. (orig. /A.B.)

  20. Fungal nanoscale metal carbonates and production of electrochemical materials.

    Science.gov (United States)

    Li, Qianwei; Gadd, Geoffrey Michael

    2017-09-01

    Fungal biomineralization of carbonates results in metal removal from solution or immobilization within a solid matrix. Such a system provides a promising method for removal of toxic or valuable metals from solution, such as Co, Ni, and La, with some carbonates being of nanoscale dimensions. A fungal Mn carbonate biomineralization process can be applied for the synthesis of novel electrochemical materials. © 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  1. UNTANGLING THE FUNGAL NICHE: A TRAIT-BASED APPROACH

    Directory of Open Access Journals (Sweden)

    Thomas W Crowther

    2014-10-01

    Full Text Available Fungi are prominent components of most terrestrial ecosystems, both in terms of biomass and ecosystem functioning, but the hyper-diverse nature of most communities has obscured the search for unifying principles governing community organization. In particular, unlike plants and animals, observational studies provide little evidence for the existence of niche processes in structuring fungal communities at broad spatial scales. This limits our capacity to predict how communities, and their functioning, vary across landscapes. We outline how a shift in focus, from taxonomy towards functional traits, might prove to be valuable in the search for general patterns in fungal ecology. We build on theoretical advances in plant and animal ecology to provide an empirical framework for a trait-based approach in fungal community ecology. Drawing upon specific characteristics of the fungal system, we highlight the significance of drought stress and combat in structuring free-living fungal communities. We propose a conceptual model to formalize how trade-offs between stress-tolerance and combative dominance are likely to organize communities across environmental gradients. Given that the survival of a fungus in a given environment is contingent on its ability to tolerate antagonistic competitors, measuring variation in combat trait expression along environmental gradients provides a means of elucidating realized, from fundamental niche spaces. We conclude that, using a trait-based understanding of how niche processes structure fungal communities across time and space, we can ultimately link communities with ecosystem functioning. Our trait-based framework highlights fundamental uncertainties that require testing in the fungal system, given their potential to uncover general mechanisms in fungal ecology.

  2. Characteristics and determinants of ambient fungal spores in Hualien, Taiwan

    Science.gov (United States)

    Ho, Hsiao-Man; Rao, Carol Y.; Hsu, Hsiao-Hsien; Chiu, Yueh-Hsiu; Liu, Chi-Ming; Chao, H. Jasmine

    Characteristics and determinants of ambient aeroallergens are of much concern in recent years because of the apparent health impacts of allergens. Yet relatively little is known about the complex behaviors of ambient aeroallergens. To address this issue, we monitored ambient fungal spores in Hualien, Taiwan from 1993-1996 to examine the compositions and temporal variations of fungi, and to evaluate possible determinants. We used a Burkard seven-day volumetric spore trap to collect daily fungal spores. Air pollutants, meteorological factors, and Asian dust events were included in the statistical analyses to predict fungal levels. We found that the most dominant fungal categories were ascospores, followed by Cladosporium and Aspergillus/Penicillium. The majority of the fungal categories had significant diurnal and seasonal variations. Total fungi, Cladosporium, Ganoderma, Arthrinium/Papularia, Cercospora, Periconia, Alternaria, Botrytis, and PM 10 had significantly higher concentrations ( p<0.05) during the period affected by Asian dust events. In multiple regression models, we found that temperature was consistently and positively associated with fungal concentrations. Other factors correlated with fungal concentrations included ozone, particulate matters with an aerodynamic diameter less than 10 μm (PM 10), relative humidity, rainfall, atmospheric pressure, total hydrocarbons, carbon monoxide, nitrogen dioxide, and sulfur dioxide. Most of the fungal categories had higher levels in 1994 than in 1995-96, probably due to urbanization of the study area. In this study, we demonstrated complicated interrelationships between fungi and air pollution/meteorological factors. In addition, long-range transport of air pollutants contributed significantly to local aeroallergen levels. Future studies should examine the health impacts of aeroallergens, as well as the synergistic/antagonistic effects of weather, and local and global-scale air pollutions.

  3. Invasive fungal infections in Colombian patients with systemic lupus erythematosus.

    Science.gov (United States)

    Santamaría-Alza, Y; Sánchez-Bautista, J; Fajardo-Rivero, J F; Figueroa, C L

    2018-06-01

    Introduction Systemic lupus erythematosus is an autoimmune disease with multi-organ involvement. Complications, such as invasive fungal infections usually occur in patients with a greater severity of the disease. Objective The objective of this study was to determine the prevalence and risk variables associated with invasive fungal infections in a Colombian systemic lupus erythematosus population. Materials and methods A cross-sectional, retrospective study that evaluated patients with systemic lupus erythematosus for six years. The primary outcome was invasive fungal infection. Descriptive, group comparison and bivariate analysis was performed using Stata 12.0 software. Results Two hundred patients were included in this study; 84.5% of the patients were women and the median age was 36 years; 68% of the subjects had haematological complications; 53.3% had nephropathy; 45% had pneumopathy and 28% had pericardial impairment; 7.5% of patients had invasive fungal infections and the most frequently isolated fungus was Candida albicans. Pericardial disease, cyclophosphamide use, high disease activity, elevated ESR, C3 hypocomplementemia, anaemia and lymphopenia had a significant association with invasive fungal infection ( P lupus erythematosus, which was higher than that reported in other latitudes. In this population the increase in disease activity, the presence of pericardial impairment and laboratory alterations (anaemia, lymphopenia, increased ESR and C3 hypocomplementemia) are associated with a greater possibility of invasive fungal infections. Regarding the use of drugs, unlike other studies, in the Colombian population an association was found only with the previous administration of cyclophosphamide. In addition, patients with invasive fungal infections and systemic lupus erythematosus had a higher prevalence of mortality and hospital readmission compared with patients with systemic lupus erythematosus without invasive fungal infection.

  4. ILC2s and fungal allergy

    Directory of Open Access Journals (Sweden)

    Hirohito Kita

    2015-07-01

    Full Text Available Innate lymphoid cells (ILCs have emerged recently as an important component of the immune system and the cell type that regulates mucosal immune responses and tissue homeostasis. Group 2 ILCs (ILC2s, a subset of ILCs, reside in various tissues and are characterized by their capacity to produce type 2 cytokines and tissue growth factors. These ILC2s play an important role in allergic immune responses by linking signals in the atmospheric environment to the immune system. Fungi are one of the major allergens associated with human asthma, and animal and in vitro models using the fungal allergens have provided significant information toward our understanding of the mechanisms of allergic disease. In mouse models of fungus-induced allergic airway inflammation, IL-33, IL-25, and TSLP are released by airway epithelial cells. Lung ILC2s that respond to these cytokines quickly produce a large quantity of type 2 cytokines, resulting in airway eosinophilia, mucus production, and airway hyperreactivity even in the absence of adaptive immune cells. Evidence also suggests that ILC2s interact with conventional immune cells, such as CD4+ T cells, and facilitate development of adaptive immune response and persistent airway inflammation. ILC2s are also present in respiratory mucosa in humans. Further investigations into the biology of ILC2s and their roles in the pathophysiology of allergic diseases will provide major conceptual advances in the field and may provide useful information toward development of new therapeutic strategies for patients.

  5. Invasive Fungal Infections Secondary to Traumatic Injury

    Directory of Open Access Journals (Sweden)

    Ryan Kronen

    2017-09-01

    Full Text Available Invasive fungal infection (IFI is a rare but serious complication of traumatic injury. The purpose of this article is to review the epidemiology, natural history, mycology, risk factors, diagnosis, treatment, and outcomes associated with post-traumatic IFI in military and civilian populations. The epidemiology of post-traumatic IFI is poorly characterized, but incidence appears to be rising. Patients often suffer from severe injuries and require extensive medical interventions. Fungi belonging to the order Mucorales are responsible for most post-traumatic IFI in both civilian and military populations. Risk factors differ between these cohorts but include specific injury patterns and comorbidities. Diagnosis of post-traumatic IFI typically follows positive laboratory results in the appropriate clinical context. The gold standard of treatment is surgical debridement in addition to systemic antifungal therapy. Patients with post-traumatic IFI may be at greater risk of amputation, delays in wound healing, hospital complications, and death as compared to trauma patients who do not develop IFI. More research is needed to understand the factors surrounding the development and management of post-traumatic IFI to reduce the significant morbidity and mortality associated with this disease.

  6. Fungal melanins and their interactions with metals.

    Science.gov (United States)

    Fogarty, R V; Tobin, J M

    1996-09-01

    Fungal melanins are dark brown or black pigments located in cell walls. They also exist as extracellular polymers. Melanized fungi possess increased virulence and resistance to microbial attack as well as enhanced survival while under environmental stress. Melanins contain various functional groups which provide an array of multiple nonequivalent binding sites for metal ions. Pigmented Cladosporium cladosporoides was shown to biosorb 2.5- to four-fold more Ni, Cu, Zn, Cd, and Pb than albino Penicillium digitatum and at four- to six-fold higher rates. Metal desorption was significantly lower for extracellular melanin than from pigmented or albino biomass which indicated the strength of the melanin-metal bond. At equilibrium, tributyltin chloride (TBTC) concentrations of 2.5 mM, pigmented and albino Aureobasidium pullulans absorbed approximately 0.9 and 0.7 mumol TBTC mg -1 dry wt, respectively, whereas purified extracellular melanin exhibited uptake levels of approximately 22 mumol TBTC mg-1 dry wt at an equilibrium concentration of only 0.4 mM. Addition of melanin to the growth medium reduced the toxic effect of CuSO4 and TBTC due to melanin metal binding and sequestration.

  7. Fungal Laccases and Their Applications in Bioremediation

    Directory of Open Access Journals (Sweden)

    Buddolla Viswanath

    2014-01-01

    Full Text Available Laccases are blue multicopper oxidases, which catalyze the monoelectronic oxidation of a broad spectrum of substrates, for example, ortho- and para-diphenols, polyphenols, aminophenols, and aromatic or aliphatic amines, coupled with a full, four-electron reduction of O2 to H2O. Hence, they are capable of degrading lignin and are present abundantly in many white-rot fungi. Laccases decolorize and detoxify the industrial effluents and help in wastewater treatment. They act on both phenolic and nonphenolic lignin-related compounds as well as highly recalcitrant environmental pollutants, and they can be effectively used in paper and pulp industries, textile industries, xenobiotic degradation, and bioremediation and act as biosensors. Recently, laccase has been applied to nanobiotechnology, which is an increasing research field, and catalyzes electron transfer reactions without additional cofactors. Several techniques have been developed for the immobilization of biomolecule such as micropatterning, self-assembled monolayer, and layer-by-layer techniques, which immobilize laccase and preserve their enzymatic activity. In this review, we describe the fungal source of laccases and their application in environment protection.

  8. Fungal Laccases Degradation of Endocrine Disrupting Compounds

    Directory of Open Access Journals (Sweden)

    Gemma Macellaro

    2014-01-01

    Full Text Available Over the past decades, water pollution by trace organic compounds (ng/L has become one of the key environmental issues in developed countries. This is the case of the emerging contaminants called endocrine disrupting compounds (EDCs. EDCs are a new class of environmental pollutants able to mimic or antagonize the effects of endogenous hormones, and are recently drawing scientific and public attention. Their widespread presence in the environment solicits the need of their removal from the contaminated sites. One promising approach to face this challenge consists in the use of enzymatic systems able to react with these molecules. Among the possible enzymes, oxidative enzymes are attracting increasing attention because of their versatility, the possibility to produce them on large scale, and to modify their properties. In this study five different EDCs were treated with four different fungal laccases, also in the presence of both synthetic and natural mediators. Mediators significantly increased the efficiency of the enzymatic treatment, promoting the degradation of substrates recalcitrant to laccase oxidation. The laccase showing the best performances was chosen to further investigate its oxidative capabilities against micropollutant mixtures. Improvement of enzyme performances in nonylphenol degradation rate was achieved through immobilization on glass beads.

  9. Fungal biology: compiling genomes and exploiting them

    Energy Technology Data Exchange (ETDEWEB)

    Labbe, Jessy L [ORNL; Uehling, Jessie K [ORNL; Payen, Thibaut [INRA; Plett, Jonathan [University of Western Sydney, Australia

    2014-01-01

    The last 10 years have seen the cost of sequencing complete genomes decrease at an incredible speed. This has led to an increase in the number of genomes sequenced in all the fungal tree of life as well as a wide variety of plant genomes. The increase in sequencing has permitted us to study the evolution of organisms on a genomic scale. A number of talks during the conference discussed the importance of transposable elements (TEs) that are present in almost all species of fungi. These TEs represent an especially large percentage of genomic space in fungi that interact with plants. Thierry Rouxel (INRA, Nancy, France) showed the link between speciation in the Leptosphaeria complex and the expansion of TE families. For example in the Leptosphaeria complex, one species associated with oilseed rape has experienced a recent and massive burst of movement by a few TE families. The alterations caused by these TEs took place in discrete regions of the genome leading to shuffling of the genomic landscape and the appearance of genes specific to the species, such as effectors useful for the interactions with a particular plant (Rouxel et al., 2011). Other presentations showed the importance of TEs in affecting genome organization. For example, in Amanita different species appear to have been invaded by different TE families (Veneault-Fourrey & Martin, 2011).

  10. Reintroduction of locally extinct vertebrates impacts arid soil fungal communities.

    Science.gov (United States)

    Clarke, Laurence J; Weyrich, Laura S; Cooper, Alan

    2015-06-01

    Introduced species have contributed to extinction of native vertebrates in many parts of the world. Changes to vertebrate assemblages are also likely to alter microbial communities through coextinction of some taxa and the introduction of others. Many attempts to restore degraded habitats involve removal of exotic vertebrates (livestock and feral animals) and reintroduction of locally extinct species, but the impact of such reintroductions on microbial communities is largely unknown. We used high-throughput DNA sequencing of the fungal internal transcribed spacer I (ITS1) region to examine whether replacing exotic vertebrates with reintroduced native vertebrates led to changes in soil fungal communities at a reserve in arid central Australia. Soil fungal diversity was significantly different between dune and swale (interdune) habitats. Fungal communities also differed significantly between sites with exotic or reintroduced native vertebrates after controlling for the effect of habitat. Several fungal operational taxonomic units (OTUs) found exclusively inside the reserve were present in scats from reintroduced native vertebrates, providing a direct link between the vertebrate assemblage and soil microbial communities. Our results show that changes to vertebrate assemblages through local extinctions and the invasion of exotic species can alter soil fungal communities. If local extinction of one or several species results in the coextinction of microbial taxa, the full complement of ecological interactions may never be restored. © 2015 John Wiley & Sons Ltd.

  11. Ocular fungal flora from healthy horses in Iran.

    Science.gov (United States)

    Khosravi, A R; Nikaein, D; Sharifzadeh, A; Gharagozlou, F

    2014-03-01

    This study was carried out in order to isolate and identify the normal conjunctival fungal flora from Caspian miniature, Thoroughbred, Turkmen and Persian Arab breeds in Tehran, Iran. A total of seventy-two adult healthy horses were studied. Ocular samples were collected from right and left eyes by using sterile cotton swabs; samples were cultured on Sabouraud dextrose agar and incubated at 30°C for 7-10 days. Molds and yeasts were identified using macro and micro-morphological and physiological characteristics. Number of fungal colonies per eye varied between 0 and 123 colony forming units (CFUs). The most predominant fungal isolates were Aspergillus (19.9%), Rhizopus (15.9%) and Penicillium (15.1%). No significant differences were observed between types of eye fungal floras in different breeds. Caspian miniature horses had significantly the highest number of fungal isolates in compare with other breeds (P<0.001), however no significant difference was observed among other breeds under study. The fungal isolates were almost the same as with studies performed in other countries, although differences in species isolated could be related to geographic and climate difference. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  12. Differential methods of localisation of fungal endophytes in the seagrasses

    Directory of Open Access Journals (Sweden)

    S. Raja

    2016-07-01

    Full Text Available Sections of three seagrass species (Halophila ovalis, Cymodocea serrulata and Halodule pinifolia were assessed for endophytes based on differential staining using light and fluorescence microscopy method. Acridine orange and aniline blue detected endophytic fungi in 20% and 10% of the segments, respectively, whereas lactophenol cotton blue was more sensitive to detect the fungal hyphae in 70% of the segments. Hyphae were the principal fungal structures generally observed under the cuticle, within the epidermal cells, mesophyll (Parenchyma cells and occasionally within the vascular tissue that varied in type, size and location within the leaf tissue. Present study also recorded the sporulation for the first time from the seagrass endophytes. Successfully amplified products of the ITS region of endophytic fungal DNA, directly from seagrass tissue and also from culture-dependent fungal DNA clearly depicted the presence of endophytic fungi in H. ovalis with two banding patterns (903 and 1381 bp confirming the presence of two dominant fungal genera. The fingerprinting of endophytic fungal community within the seagrass tissue was assessed using denaturing gradient gel electrophoresis (DGGE that derived with multiple bands that clarified the presence of more than one taxon within the seagrass tissue.

  13. Plasma membrane lipids and their role in fungal virulence.

    Science.gov (United States)

    Rella, Antonella; Farnoud, Amir M; Del Poeta, Maurizio

    2016-01-01

    There has been considerable evidence in recent years suggesting that plasma membrane lipids are important regulators of fungal pathogenicity. Various glycolipids have been shown to impart virulent properties in several fungal species, while others have been shown to play a role in host defense. In addition to their role as virulence factors, lipids also contribute to other virulence mechanisms such as drug resistance, biofilm formation, and release of extracellular vesicles. In addition, lipids also affect the mechanical properties of the plasma membrane through the formation of packed microdomains composed mainly of sphingolipids and sterols. Changes in the composition of lipid microdomains have been shown to disrupt the localization of virulence factors and affect fungal pathogenicity. This review gathers evidence on the various roles of plasma membrane lipids in fungal virulence and how lipids might contribute to the different processes that occur during infection and treatment. Insight into the role of lipids in fungal virulence can lead to an improved understanding of the process of fungal pathogenesis and the development of new lipid-mediated therapeutic strategies. Published by Elsevier Ltd.

  14. Changes in Soil Fungal Community Structure with Increasing Disturbance Frequency.

    Science.gov (United States)

    Cho, Hyunjun; Kim, Mincheol; Tripathi, Binu; Adams, Jonathan

    2017-07-01

    Although disturbance is thought to be important in many ecological processes, responses of fungal communities to soil disturbance have been little studied experimentally. We subjected a soil microcosm to physical disturbance, at a range of frequencies designed to simulate ecological disturbance events. We analyzed the fungal community structure using Illumina HiSeq sequencing of the ITS1 region. Fungal diversity was found to decline with the increasing disturbance frequencies, with no sign of the "humpback" pattern found in many studies of larger sedentary organisms. There is thus no evidence of an effect of release from competition resulting from moderate disturbance-which suggests that competition and niche overlap may not be important in limiting soil fungal diversity. Changing disturbance frequency also led to consistent differences in community composition. There were clear differences in OTU-level composition, with different disturbance treatments each having distinct fungal communities. The functional profile of fungal groups (guilds) was changed by the level of disturbance frequency. These predictable differences in community composition suggest that soil fungi can possess different niches in relation to disturbance frequency, or time since last disturbance. Fungi appear to be most abundant relative to bacteria at intermediate disturbance frequencies, on the time scale we studied here.

  15. Fungal contamination assessment in Portuguese elderly care centers.

    Science.gov (United States)

    Viegas, C; Almeida-Silva, M; Gomes, A Quintal; Wolterbeek, H T; Almeida, S M

    2014-01-01

    Individuals spend 80-90% of their day indoors and elderly subjects are likely to spend even a greater amount of time indoors. Thus, indoor air pollutants such as bioaerosols may exert a significant impact on this age group. The aim of this study was to characterize fungal contamination within Portuguese elderly care centers. Fungi were measured using conventional as well as molecular methods in bedrooms, living rooms, canteens, storage areas, and outdoors. Bioaerosols were evaluated before and after the microenvironments' occupancy in order to understand the role played by occupancy in fungal contamination. Fungal load results varied from 32 colony-forming units CFU m(-3) in bedrooms to 228 CFU m(-3) in storage areas. Penicillium sp. was the most frequently isolated (38.1%), followed by Aspergillus sp. (16.3%) and Chrysonilia sp. (4.2%). With respect to Aspergillus genus, three different fungal species in indoor air were detected, with A. candidus (62.5%) the most prevalent. On surfaces, 40 different fungal species were isolated and the most frequent was Penicillium sp. (22.2%), followed by Aspergillus sp. (17.3%). Real-time polymerase chain reaction did not detect the presence of A. fumigatus complex. Species from Penicillium and Aspergillus genera were the most abundant in air and surfaces. The species A. fumigatus was present in 12.5% of all indoor microenvironments assessed. The living room was the indoor microenvironment with lowest fungal concentration and the storage area was highest.

  16. High turnover of fungal hyphae in incubation experiments.

    Science.gov (United States)

    de Vries, Franciska T; Bååth, Erland; Kuyper, Thom W; Bloem, Jaap

    2009-03-01

    Soil biological studies are often conducted on sieved soils without the presence of plants. However, soil fungi build delicate mycelial networks, often symbiotically associated with plant roots (mycorrhizal fungi). We hypothesized that as a result of sieving and incubating without plants, the total fungal biomass decreases. To test this, we conducted three incubation experiments. We expected total and arbuscular mycorrhizal (AM) fungal biomass to be higher in less fertilized soils than in fertilized soils, and thus to decrease more during incubation. Indeed, we found that fungal biomass decreased rapidly in the less fertilized soils. A shift towards thicker hyphae occurred, and the fraction of septate hyphae increased. However, analyses of phospholipid fatty acids (PLFAs) and neutral lipid fatty acids could not clarify which fungal groups were decreasing. We propose that in our soils, there was a fraction of fungal biomass that was sensitive to fertilization and disturbance (sieving, followed by incubation without plants) with a very high turnover (possibly composed of fine hyphae of AM and saprotrophic fungi), and a fraction that was much less vulnerable with a low turnover (composed of saprotrophic fungi and runner hyphae of AMF). Furthermore, PLFAs might not be as sensitive in detecting changes in fungal biomass as previously thought.

  17. An Estimate of the Burden of Fungal Disease in Norway

    Directory of Open Access Journals (Sweden)

    Ingvild Nordøy

    2018-02-01

    Full Text Available The aim of this study was to examine the burden of fungal disease in Norway, contributing to a worldwide effort to improve awareness of the needs for better diagnosis and treatment of such infections. We used national registers and actual data from the Departments of Microbiology from 2015 and estimated the incidence and/or prevalence of superficial, allergic and invasive fungal disease using published reports on specific populations at risk. One in 6 Norwegians suffered from fungal disease: Superficial skin infections (14.3%: 745,600 and recurrent vulvovaginal candidiasis in fertile women (6%: 43,123 were estimated to be the most frequent infections. Allergic fungal lung disease was estimated in 17,755 patients (341/100,000. Pneumocystis jirovecii was diagnosed in 262 patients (5/100,000, invasive candidiasis in 400 patients (7.7/100,000, invasive aspergillosis in 278 patients (5.3/100,000 and mucormycosis in 7 patients (0.1/100,000. Particular fungal infections from certain geographic areas were not observed. Overall, 1.79% of the population was estimated to be affected by serious fungal infections in Norway in 2015. Even though estimates for invasive infections are small, the gravity of such infections combined with expected demographic changes in the future emphasizes the need for better epidemiological data.

  18. Evaluation of nested PCR in diagnosis of fungal rhinosinusitis.

    Science.gov (United States)

    Badiee, Parisa; Gandomi, Behrooz; Sabz, Gholamabbass; Khodami, Bijan; Choopanizadeh, Maral; Jafarian, Hadis

    2015-02-01

    Given the importance of rapid diagnosis for fungal rhinosinusitis, this study aimed to evaluate the use of nested PCR to identify Aspergillus and Mucor species in clinical samples from patients with suspected fungal rhinosinusitis. Functional endoscopic sinus surgery specimens were collected from 98 patients with rhinosinusitis from 2012 to 2013. All samples were ground and cultured on sabouraud dextrose agar. The isolated fungi were identified based on their macroscopic and microscopic features. Fungal DNA was extracted from the tissue samples and nested PCR was performed with two sets of primers for Mucor and Aspergillus. Direct microscopic showed that 5.1% contained fungal components and 9.2% exhibited growth of fungi in culture. The most common agents isolated were Aspergillus fumigatus (n= 3), Aspergillus flavus (n=2), Penicillium sp (n=3) and Alternaria sp. (n=1). Mucor sp. was identified in the pathology smear from 1 patient. Positive results for fungal rhinosinusitis were obtained for a total of 10.2% by culture or pathology smear. Positive PCR results were obtained in 72 samples for Aspergillus and 31 samples for Mucor. Our results suggest that endoscopic sinus surgery specimens are not suitable for nested PCR, probably because of the accumulation of fungi that contaminate the environmental air. This drawback is a limiting factor for diagnosis with nasal cavity specimens. Therefore, molecular methods and conventional culture techniques are helpful complementary diagnostic methods to detect fungal rhinosinusitis and determine appropriate management for these patients.

  19. Comparison on the sensitivity of laboratory diagnosis technology in the diagnosis of fungal keratitis

    Directory of Open Access Journals (Sweden)

    Peng-Fei Chen

    2015-08-01

    Full Text Available AIM: To analyze the correlation and clinical significance of fungal smear, fungal culture and pathological examination in the diagnosis of fungalkeratitis. METHODS:One hundred and ten cases(110 eyeswith fungal keratitis from January 2012 to December 2014 were collected. The results of fungal smear, fungal culture and pathological examination results were analyzed retrospectively. Fungal smear was detected by 10% KOH wet microscopy and gram staining microscopy. Fungal culture was used potato dextrose agar(PDAmedium. The specimens of pathological examination were from corneal transplantation surgery. paraffin section, HE and hexamine silver and PAS staining was used in the pathological examination. RESULTS:Of the 110 cases of fungal keratitis, fungal smear positive were observed in 50 cases(45.5%, fungal culture positive were observed in 55 cases(50.0%; pathological examination positive were observed in 88 cases(80.0%. Fifty cases were both fungal smear and pathological examination positive and 22 cases were both fungal smear and pathological examination negative. The coincidence rate of fungal smear and pathologic examination was 65.5%. Fifty-five cases were both fungal culture and pathological examination positive and 22 cases were both fungal culture and pathological examination negative. The coincidence rate of fungal culture and pathologic examination was 70.0%. In the 60 cases of fungal smear negative results, 38 cases(63.3%were confirmed positive through pathological examination. In the 55 cases of fungus culture negative results, 33 cases(60.0%were confirmed positive by pathological examination. CONCLUSION:The accuracy of pathological examination is the highest. The combined application of fungal smear, fungal culture and pathological examination can improve the diagnostic accuracy of fungal keratitis.

  20. PKC signaling regulates drug resistance of the fungal pathogen Candida albicans via circuitry comprised of Mkc1, calcineurin, and Hsp90.

    Directory of Open Access Journals (Sweden)

    Shantelle L LaFayette

    2010-08-01

    Full Text Available Fungal pathogens exploit diverse mechanisms to survive exposure to antifungal drugs. This poses concern given the limited number of clinically useful antifungals and the growing population of immunocompromised individuals vulnerable to life-threatening fungal infection. To identify molecules that abrogate resistance to the most widely deployed class of antifungals, the azoles, we conducted a screen of 1,280 pharmacologically active compounds. Three out of seven hits that abolished azole resistance of a resistant mutant of the model yeast Saccharomyces cerevisiae and a clinical isolate of the leading human fungal pathogen Candida albicans were inhibitors of protein kinase C (PKC, which regulates cell wall integrity during growth, morphogenesis, and response to cell wall stress. Pharmacological or genetic impairment of Pkc1 conferred hypersensitivity to multiple drugs that target synthesis of the key cell membrane sterol ergosterol, including azoles, allylamines, and morpholines. Pkc1 enabled survival of cell membrane stress at least in part via the mitogen activated protein kinase (MAPK cascade in both species, though through distinct downstream effectors. Strikingly, inhibition of Pkc1 phenocopied inhibition of the molecular chaperone Hsp90 or its client protein calcineurin. PKC signaling was required for calcineurin activation in response to drug exposure in S. cerevisiae. In contrast, Pkc1 and calcineurin independently regulate drug resistance via a common target in C. albicans. We identified an additional level of regulatory control in the C. albicans circuitry linking PKC signaling, Hsp90, and calcineurin as genetic reduction of Hsp90 led to depletion of the terminal MAPK, Mkc1. Deletion of C. albicans PKC1 rendered fungistatic ergosterol biosynthesis inhibitors fungicidal and attenuated virulence in a murine model of systemic candidiasis. This work establishes a new role for PKC signaling in drug resistance, novel circuitry through which

  1. Identification of potentially safe promising fungal cell factories for the production of polyketide natural food colorants using chemotaxonomic rationale

    Directory of Open Access Journals (Sweden)

    Frisvad Jens C

    2009-04-01

    of chemotaxonomic tools and a priori knowledge of fungal extrolites is a rational approach towards selection of fungal polyketide pigment producers considering the enormous chemical diversity and biodiversity of ascomycetous fungi. This rationale could be very handy for the selection of potentially safe fungal cell factories not only for polyketide pigments but also for the other industrially important polyketides; the molecular and genetic basis for the biosynthesis of which has not yet been examined in detail. In addition, 4 out of the 10 chemotaxonomically selected promising Penicillium strains were shown to produce extracellular pigments in the liquid media using a solid support indicating future cell factory possibilities for polyketide natural food colorants.

  2. Clinical use of fungal PCR from deep tissue samples in the diagnosis of invasive fungal diseases: a retrospective observational study.

    Science.gov (United States)

    Ala-Houhala, M; Koukila-Kähkölä, P; Antikainen, J; Valve, J; Kirveskari, J; Anttila, V-J

    2018-03-01

    To assess the clinical use of panfungal PCR for diagnosis of invasive fungal diseases (IFDs). We focused on the deep tissue samples. We first described the design of panfungal PCR, which is in clinical use at Helsinki University Hospital. Next we retrospectively evaluated the results of 307 fungal PCR tests performed from 2013 to 2015. Samples were taken from normally sterile tissues and fluids. The patient population was nonselected. We classified the likelihood of IFD according to the criteria of the 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), comparing the fungal PCR results to the likelihood of IFD along with culture and microscopy results. There were 48 positive (16%) and 259 negative (84%) PCR results. The sensitivity and specificity of PCR for diagnosing IFDs were 60.5% and 91.7%, respectively, while the negative predictive value and positive predictive value were 93.4% and 54.2%, respectively. The concordance between the PCR and the culture results was 86% and 87% between PCR and microscopy, respectively. Of the 48 patients with positive PCR results, 23 had a proven or probable IFD. Fungal PCR can be useful for diagnosing IFDs in deep tissue samples. It is beneficial to combine fungal PCR with culture and microscopy. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  3. Intra-antral application of an anti-fungal agent for recurrent maxillary fungal rhinosinusitis: a case report

    Directory of Open Access Journals (Sweden)

    Dunmade Adekunle D

    2012-08-01

    Full Text Available Abstract Introduction Fungal infection of the paranasal sinuses is an increasingly recognized entity both in immunocompetent and immunocompromised individuals. Treatment has been via use of either surgical or medical modalities, or a combination of the two. Here, we present a case of utilization of intra-antral application of an anti-fungal agent in the management of recurrent fungal sinusitis in an indigent Nigerian patient. Case presentation We present the case of a 30-year-old West African Yoruba man, an indigent Nigerian clergyman, who presented to our facility with a history of recurrent nasal discharge (about one year, recurrent nasal blockage (about five months, and right facial swelling (about one week. After intra-nasal antrostomy for debulking with a systemic anti-fungal agent, our patient had a recurrence after four months. Our patient subsequently had an intra-antral application of flumetasone and clioquinol (Locacorten®-Vioform® weekly for six weeks with improvement of symptoms and no recurrence after six months of follow-up. Conclusions We conclude that topical intra-antral application of anti-fungal agents is effective in patients with recurrent fungal maxillary sinusitis after surgical debulking.

  4. Arogenate Dehydratase Isoforms Differentially Regulate Anthocyanin Biosynthesis in Arabidopsis thaliana.

    Science.gov (United States)

    Chen, Qingbo; Man, Cong; Li, Danning; Tan, Huijuan; Xie, Ye; Huang, Jirong

    2016-12-05

    Anthocyanins, a group of L-phenylalanine (Phe)-derived flavonoids, have been demonstrated to play important roles in plant stress resistance and interactions between plants and insects. Although the anthocyanin biosynthetic pathway and its regulatory mechanisms have been extensively studied, it remains unclear whether the level of Phe supply affects anthocyanin biosynthesis. Here, we investigated the roles of arogenate dehydratases (ADTs), the key enzymes that catalyze the conversion of arogenate into Phe, in sucrose-induced anthocyanin biosynthesis in Arabidopsis. Genetic analysis showed that all six ADT isoforms function redundantly in anthocyanin biosynthesis but have differential contributions. ADT2 contributes the most to anthocyanin accumulation, followed by ADT1 and ADT3, and ADT4-ADT6. We found that anthocyanin content is positively correlated with the levels of Phe and sucrose-induced ADT transcripts in seedlings. Consistently, addition of Phe to the medium could dramatically increase anthocyanin content in the wild-type plants and rescue the phenotype of the adt1 adt3 double mutant regarding the anthocyanin accumulation. Moreover, transgenic plants overexpressing ADT4, which appears to be less sensitive to Phe than overexpression of ADT2, hyperaccumulate Phe and produce elevated level of anthocyanins. Taken together, our results suggest that the level of Phe is an important regulatory factor for sustaining anthocyanin biosynthesis. Copyright © 2016 The Author. Published by Elsevier Inc. All rights reserved.

  5. The magnesium chelation step in chlorophyll biosynthesis. Progress report 1993

    Energy Technology Data Exchange (ETDEWEB)

    Weinstein, J.D.

    1993-12-31

    Progress is reported on the identification and fractionation of Magnesium chealatase, an enzyme involved in addition of Mg to chlorophyll during the later`s biosynthesis. Progress is documented as a series of synopsis of published and unpublished papers by the author.

  6. Biosynthesis of silver nanoparticles and its antibacterial activity ...

    African Journals Online (AJOL)

    In the present research work, biosynthesis of silver nanoparticles and its activity on bacterial pathogens were investigated. Silver nanoparticles were rapidly synthesized using Urospora sp. and the formation of nanoparticles was observed within 30 min. The results recorded from UV–vis spectrum, Fourier Transform Infrared ...

  7. Lincosamides: Chemical structure, biosynthesis, mechanism of action, resistance, and applications

    Czech Academy of Sciences Publication Activity Database

    Spížek, Jaroslav; Řezanka, Tomáš

    2017-01-01

    Roč. 133, June 1 SI (2017), s. 20-28 ISSN 0006-2952 Institutional support: RVO:61388971 Keywords : Lincosamides * Chemical structure * Biosynthesis and mechanism of action Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 4.581, year: 2016

  8. WRKY transcription factors involved in activation of SA biosynthesis genes

    NARCIS (Netherlands)

    van Verk, Marcel C; Bol, John F; Linthorst, Huub J M

    2011-01-01

    Increased defense against a variety of pathogens in plants is achieved through activation of a mechanism known as systemic acquired resistance (SAR). The broad-spectrum resistance brought about by SAR is mediated through salicylic acid (SA). An important step in SA biosynthesis in Arabidopsis is the

  9. Molecular and biochemical studies of fragrance biosynthesis in rose

    NARCIS (Netherlands)

    Sun, P.

    2017-01-01

    Roses are one of the most popular ornamental plants, whose floral volatiles are not only involved in environmental interactions but also widely used by industries. The biosynthesis of many of these volatiles in roses is not well understood. This thesis describes alternative pathways for the

  10. Hacking an Algal Transcription Factor for Lipid Biosynthesis.

    Science.gov (United States)

    Chen, Xiulai; Hu, Guipeng; Liu, Liming

    2018-03-01

    Transcriptional engineering is a viable means for engineering microalgae to produce lipid, but it often results in a trade-off between production and growth. A recent study shows that engineering a single transcriptional regulator enables efficient carbon partitioning to lipid biosynthesis with high biomass productivity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Bile acid analysis in human disorders of bile acid biosynthesis

    NARCIS (Netherlands)

    Vaz, Frédéric M.; Ferdinandusse, Sacha

    2017-01-01

    Bile acids facilitate the absorption of lipids in the gut, but are also needed to maintain cholesterol homeostasis, induce bile flow, excrete toxic substances and regulate energy metabolism by acting as signaling molecules. Bile acid biosynthesis is a complex process distributed across many cellular

  12. Biosynthesis and Characterization of Silver Nanoparticles by Aspergillus Species

    Science.gov (United States)

    Pourshahid, Seyedmohammad; Mehryar, Pouyan; Pakshir, Keyvan; Rahimi, Mohammad Javad; Arabi Monfared, Ali

    2016-01-01

    Currently, researchers turn to natural processes such as using biological microorganisms in order to develop reliable and ecofriendly methods for the synthesis of metallic nanoparticles. In this study, we have investigated extracellular biosynthesis of silver nanoparticles using four Aspergillus species including A. fumigatus, A. clavatus, A. niger, and A. flavus. We have also analyzed nitrate reductase activity in the studied species in order to determine the probable role of this enzyme in the biosynthesis of silver nanoparticles. The formation of silver nanoparticles in the cell filtrates was confirmed by the passage of laser light, change in the color of cell filtrates, absorption peak at 430 nm in UV-Vis spectra, and atomic force microscopy (AFM). There was a logical relationship between the efficiencies of studied Aspergillus species in the production of silver nanoparticles and their nitrate reductase activity. A. fumigatus as the most efficient species showed the highest nitrate reductase activity among the studied species while A. flavus exhibited the lowest capacity in the biosynthesis of silver nanoparticles which was in accord with its low nitrate reductase activity. The present study showed that Aspergillus species had potential for the biosynthesis of silver nanoparticles depending on their nitrate reductase activity. PMID:27652264

  13. Regulation of Isoprenoid Pheromone Biosynthesis in Bumblebee Males

    Czech Academy of Sciences Publication Activity Database

    Prchalová, Darina; Buček, Aleš; Brabcová, Jana; Žáček, Petr; Kindl, Jiří; Valterová, Irena; Pichová, Iva

    2016-01-01

    Roč. 17, č. 3 (2016), s. 260-267 ISSN 1439-4227 R&D Projects: GA MŠk LO1302; GA ČR GA15-06569S Institutional support: RVO:61388963 Keywords : biosynthesis * Bombus spp. * gene expression * isoprenoid s * pheromones * transcriptional regulation Subject RIV: CE - Biochemistry Impact factor: 2.847, year: 2016

  14. Expression profiles of genes involved in tanshinone biosynthesis of ...

    Indian Academy of Sciences (India)

    Expression profiles of genes involved in tanshinone biosynthesis of two. Salvia miltiorrhiza genotypes with different tanshinone contents. Zhenqiao Song, Jianhua Wang and Xingfeng Li. J. Genet. 95, 433–439. Table 1. S. miltiorrhiza genes and primer pairs used for qRT-PCR. Gene. GenBank accession. Primer name.

  15. Temporal expression of genes involved in the biosynthesis of ...

    African Journals Online (AJOL)

    Gibberellins (GAs) are a large family of endogenous plant growth regulators. Bioactive GAs influence nearly all processes during plant growth and development. In the present study, we cloned and identified 10 unique genes that are potentially involved in the biosynthesis of GAs, including one BpGGDP gene, two BpCPS ...

  16. Anthocyanin biosynthesis in fruit tree crops: Genes and their regulation

    African Journals Online (AJOL)

    The anthocyanin biosynthesis pathway is a little complex with branches responsible for the synthesis of a variety of metabolites. In fruit tree crops, during the past decade, many structural genes encoding enzymes in the anthocyanin biosynthetic pathway and various regulatory genes encoding transcription factors that ...

  17. Biosynthesis of silver nanoparticles and its antibacterial activity ...

    African Journals Online (AJOL)

    Dr.Rajasekar

    2012-07-19

    Jul 19, 2012 ... Available online at http://www.academicjournals.org/AJB ... Transmission Electron Microscopy (HRTEM) support the biosynthesis and characterization of silver nanoparticles. ... nanoparticle from seaweed is a green chemical method ... operating at a voltage of 80 kV and a current of 30 mA (Chandran.

  18. Cyclopiazonic Acid Biosynthesis of Aspergillus flavus and Aspergillus oryzae

    Science.gov (United States)

    Cyclopiazonic acid (CPA) is an indole-tetramic acid neurotoxin produced by some of the same strains of A. flavus that produce aflatoxins and by some Aspergillus oryzae strains. Despite its discovery 40 years ago, few reviews of its toxicity and biosynthesis have been reported. This review examines w...

  19. Biosynthesis of silver nanoparticles by Leishmania tropica | Rahi ...

    African Journals Online (AJOL)

    A novel biosynthesis route for Silver Nanoparticles (Ag-NPs) was attempted in the present study using Leishmania tropica the causative agent of cutaneous leishmaniasis in different countries, particularly in Mediterranean region in Iraq. Silver nanoparticles were successfully synthesized from AgNO3 by reduction of ...

  20. Stimulation of reserpine biosynthesis in the callus of Rauvolfia ...

    African Journals Online (AJOL)

    So enhancing this alkaloid in the already available system is a beneficial approach. Tryptophan is the starting material in the biosynthesis of reserpine. Callus was induced from leaf explants of Rauvolfia tetraphylla L. on MS medium supplemented with the combination of 9 μM 2,4-D and 25, 50, 75 and 100 mg/l tryptophan.

  1. Whole-cell fungal transformation of precursors into dyes

    Directory of Open Access Journals (Sweden)

    Jarosz-Wilkołazka Anna

    2010-07-01

    Full Text Available Abstract Background Chemical methods of producing dyes involve extreme temperatures and unsafe toxic compounds. Application of oxidizing enzymes obtained from fungal species, for example laccase, is an alternative to chemical synthesis of dyes. Laccase can be replaced by fungal biomass acting as a whole-cell biocatalyst with properties comparable to the isolated form of the enzyme. The application of the whole-cell system simplifies the transformation process and reduces the time required for its completion. In the present work, four fungal strains with a well-known ability to produce laccase were tested for oxidation of 17 phenolic and non-phenolic precursors into stable and non-toxic dyes. Results An agar-plate screening test of the organic precursors was carried out using four fungal strains: Trametes versicolor, Fomes fomentarius, Abortiporus biennis, and Cerrena unicolor. Out of 17 precursors, nine were transformed into coloured substances in the presence of actively growing fungal mycelium. The immobilized fungal biomass catalyzed the transformation of 1 mM benzene and naphthalene derivatives in liquid cultures yielding stable and non-toxic products with good dyeing properties. The type of fungal strain had a large influence on the absorbance of the coloured products obtained after 48-hour transformation of the selected precursors, and the most effective was Fomes fomentarius (FF25. Whole-cell transformation of AHBS (3-amino-4-hydroxybenzenesulfonic acid into a phenoxazinone dye was carried out in four different systems: in aqueous media comprising low amounts of carbon and nitrogen source, in buffer, and in distilled water. Conclusions This study demonstrated the ability of four fungal strains belonging to the ecological type of white rot fungi to transform precursors into dyes. This paper highlights the potential of fungal biomass for replacing isolated enzymes as a cheaper industrial-grade biocatalyst for the synthesis of dyes and other

  2. Climate Controls AM Fungal Distributions from Global to Local Scales

    Science.gov (United States)

    Kivlin, S. N.; Hawkes, C.; Muscarella, R.; Treseder, K. K.; Kazenel, M.; Lynn, J.; Rudgers, J.

    2016-12-01

    Arbuscular mycorrhizal (AM) fungi have key functions in terrestrial biogeochemical processes; thus, determining the relative importance of climate, edaphic factors, and plant community composition on their geographic distributions can improve predictions of their sensitivity to global change. Local adaptation by AM fungi to plant hosts, soil nutrients, and climate suggests that all of these factors may control fungal geographic distributions, but their relative importance is unknown. We created species distribution models for 142 AM fungal taxa at the global scale with data from GenBank. We compared climate variables (BioClim and soil moisture), edaphic variables (phosphorus, carbon, pH, and clay content), and plant variables using model selection on models with (1) all variables, (2) climatic variables only (including soil moisture) and (3) resource-related variables only (all other soil parameters and NPP) using the MaxEnt algorithm evaluated with ENMEval. We also evaluated whether drivers of AM fungal distributions were phylogenetically conserved. To test whether global correlates of AM fungal distributions were reflected at local scales, we then surveyed AM fungi in nine plant hosts along three elevation gradients in the Upper Gunnison Basin, Colorado, USA. At the global scale, the distributions of 55% of AM fungal taxa were affected by both climate and soil resources, whereas 16% were only affected by climate and 29% were only affected by soil resources. Even for AM fungi that were affected by both climate and resources, the effects of climatic variables nearly always outweighed those of resources. Soil moisture and isothermality were the main climatic and NPP and soil carbon the main resource related factors influencing AM fungal distributions. Distributions of closely related AM fungal taxa were similarly affected by climate, but not by resources. Local scale surveys of AM fungi across elevations confirmed that climate was a key driver of AM fungal

  3. Coordinative compounds of molybdenum and vanadium as possible stimulators of extracellular cellulases biosynthesis of micromycetes Penicillium expansum CNMN FD 05 C

    International Nuclear Information System (INIS)

    Chilochi, A.A.; Tyurina, Zh.P.; Klapko, S.F.; Lablyuk, S.V.; Pasha, L.I.; Bologa, O.A.; Koropchanu, Eh.B.; Rizha, A.P.

    2012-01-01

    The effect of coordinative compounds of molybdenum and vanadium on the biosynthesis of cellulosolytic enzymatic complex (endoglucanases, celobiohydrolases, β-glucosidases) of the fungal strain Penicillium expansum CNMN FD 05C was investigated. It was established that complexes of molybdenum, which contain amino acids in its composition, have a neutral effect on the activity of endoglucanases, inhibit celobiohydrolases (80-90%) and stimulate the activity of β-glucosidases. Among the most effective stimulators of β-glucosidases synthesis, the complex MoO 2 (ac.ac.)Gly may be mentioned, that increases the enzymatic activity by 47.8-67.0%. This complex can be used to obtain an enzymatic preparation with a high content of β-glucosidases. The metal complex (NH 4 ) 2 VO 3 Gly stimulates the activity of enzymes of the cellulosolytic complex of the fungi Penicillium expansum CNMN FD 05C, increasing the endogluconasic activity by 45%, cellobiohydrolasic by 32% and β-glucosidasic by 40%.

  4. The prevalence of selected genes involved in the biosynthesis of trichothecenes assessed with the specific PCR tests in Fusarium spp. isolated from cereals in southern Poland.

    Science.gov (United States)

    Wolny-Koładka, Katarzyna A

    2015-01-01

    The analysis was conducted using 50 isolates of fungi of the genus Fusarium belonging to the species classified as major trichothecene mycotoxin producers: F. graminearum, F. culmorum, F. sporotrichioides, and F. poae. The tested fungi were isolated from ears of cereal crops in southern Poland during the two growing seasons (2011 and 2012). The aim of this study was to evaluate the prevalence of genes involved in the biosynthesis of trichothecene mycotoxins using the specific PCR tests. Molecular analyses indicated that the genes responsible for the production of trichothecenes (Tri3, Tri5, Tri7, Tri13) were abundant in the examined genetic material. The tested fungal isolates were characterized by a large diversity in terms of the number and composition of the possessed Tri genes. On the other hand, 14 of 50 isolates were found not to carry any of Tri genes.

  5. Structural characteristics of ScBx genes controlling the biosynthesis of hydroxamic acids in rye (Secale cereale L.).

    Science.gov (United States)

    Bakera, Beata; Makowska, Bogna; Groszyk, Jolanta; Niziołek, Michał; Orczyk, Wacław; Bolibok-Brągoszewska, Hanna; Hromada-Judycka, Aneta; Rakoczy-Trojanowska, Monika

    2015-08-01

    Benzoxazinoids (BX) are major secondary metabolites of gramineous plants that play an important role in disease resistance and allelopathy. They also have many other unique properties including anti-bacterial and anti-fungal activity, and the ability to reduce alfa-amylase activity. The biosynthesis and modification of BX are controlled by the genes Bx1 ÷ Bx10, GT and glu, and the majority of these Bx genes have been mapped in maize, wheat and rye. However, the genetic basis of BX biosynthesis remains largely uncharacterized apart from some data from maize and wheat. The aim of this study was to isolate, sequence and characterize five genes (ScBx1, ScBx2, ScBx3, ScBx4 and ScBx5) encoding enzymes involved in the synthesis of DIBOA, an important defense compound of rye. Using a modified 3D procedure of BAC library screening, seven BAC clones containing all of the ScBx genes were isolated and sequenced. Bioinformatic analyses of the resulting contigs were used to examine the structure and other features of these genes, including their promoters, introns and 3'UTRs. Comparative analysis showed that the ScBx genes are similar to those of other Poaceae species, especially to the TaBx genes. The polymorphisms present both in the coding sequences and non-coding regions of ScBx in relation to other Bx genes are predicted to have an impact on the expression, structure and properties of the encoded proteins.

  6. PcFKH1, a novel regulatory factor from the forkhead family, controls the biosynthesis of penicillin in Penicillium chrysogenum.

    Science.gov (United States)

    Domínguez-Santos, Rebeca; García-Estrada, Carlos; Kosalková, Katarina; Prieto, Carlos; Santamarta, Irene; Martín, Juan-Francisco

    2015-08-01

    Penicillin biosynthesis in Penicillium chrysogenum (re-identified as Penicillium rubens) is a good example of a biological process subjected to complex global regulatory networks and serves as a model to study fungal secondary metabolism. The winged-helix family of transcription factors recently described, which includes the forkhead type of proteins, is a key type of regulatory proteins involved in this process. In yeasts and humans, forkhead transcription factors are involved in different processes (cell cycle regulation, cell death control, pre-mRNA processing and morphogenesis); one member of this family of proteins has been identified in the P. chrysogenum genome (Pc18g00430). In this work, we have characterized this novel transcription factor (named PcFKH1) by generating knock-down mutants and overexpression strains. Results clearly indicate that PcFKH1 positively controls antibiotic biosynthesis through the specific interaction with the promoter region of the penDE gene, thus regulating penDE mRNA levels. PcFKH1 also binds to the pcbC promoter, but with low affinity. In addition, it also controls other ancillary genes of the penicillin biosynthetic process, such as phlA (encoding phenylacetyl CoA ligase) and ppt (encoding phosphopantetheinyl transferase). PcFKH1 also plays a role in conidiation and spore pigmentation, but it does not seem to be involved in hyphal morphology or cell division in the improved laboratory reference strain Wisconsin 54-1255. A genome-wide analysis of processes putatively coregulated by PcFKH1 and PcRFX1 (another winged-helix transcription factor) in P. chrysogenum provided evidence of the global effect of these transcription factors in P. chrysogenum metabolism. Copyright © 2015 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  7. Pulsed growth of fungal hyphal tips.

    Science.gov (United States)

    López-Franco, R; Bartnicki-Garcia, S; Bracker, C E

    1994-12-06

    Somatic fungal hyphae are generally assumed to elongate at steady linear rates when grown under constant environmental conditions with ample nutrients. However, patterns of pulsed hyphal elongation were detected during apparent steady growth of hyphal tips in fungi from several major taxonomic groups (Oomycetes, Pythium aphanidermatum and Saprolegnia ferax; Zygomycetes, Gilbertella persicaria; Deuteromycetes, Trichoderma viride; Ascomycetes, Neurospora crassa and Fusarium culmorum; Basidiomycetes, Rhizoctonia solani). Growing hyphal tips were recorded with video-enhanced phase-contrast microscopy at high magnification, and digital images were measured at very short time intervals (1-5 s). In all fungi tested, the hyphal elongation rate was never perfectly steady but fluctuated continuously with alternating periods of fast and slow growth at more or less regular intervals. Pulsed growth was observed in fungi differing in cell diameter, overall growth rate, taxonomic position, and presence and pattern of Spitzenkörper organization, suggesting that this is a general phenomenon. Frequency and amplitude of the pulses varied among the test organisms. T. viride and N. crassa showed the most frequent pulses (average of 13-14 per min), and F. culmorum the least frequent (2.7 per min). Average pulse amplitude varied from 0.012 microns/s for F. culmorum to 0.068 microns/s for G. persicaria. In F. culmorum and T. viride, the fast phase of the growth pulses was correlated with the merger of satellite Spitzenkörper with the main Spitzenkörper. These findings are consistent with a causal relationship between fluctuations in the overall rate of secretory vesicle delivery/discharge at the hyphal apex and the fluctuations in hyphal elongation rate.

  8. PR Toxin – Biosynthesis, Genetic Regulation, Toxicological Potential, Prevention and Control Measures: Overview and Challenges

    Directory of Open Access Journals (Sweden)

    Manish K. Dubey

    2018-03-01

    Full Text Available Out of the various mycotoxigenic food and feed contaminant, the fungal species belonging to Penicillium genera, particularly Penicillium roqueforti is of great economic importance, and well known for its crucial role in the manufacturing of Roquefort and Gorgonzola cheese. The mycotoxicosis effect of this mold is due to secretion of several metabolites, of which PR toxin is of considerable importance, with regard to food quality and safety challenges issues. The food products and silages enriched with PR toxin could lead into damage to vital internal organs, gastrointestinal perturbations, carcinogenicity, immunotoxicity, necrosis, and enzyme inhibition. Moreover, it also has the significant mutagenic potential to disrupt/alter the crucial processes like DNA replication, transcription, and translation at the molecular level. The high genetic diversities in between the various strains of P. roqueforti persuaded their nominations with Protected Geographical Indication (PGI, accordingly to the cheese type, they have been employed. Recently, the biosynthetic mechanism and toxicogenetic studies unraveled the role of ari1 and prx gene clusters that cross-talk with the synthesis of other metabolites or involve other cross-regulatory pathways to negatively regulate/inhibit the other biosynthetic route targeted for production of a strain-specific metabolites. Interestingly, the chemical conversion that imparts toxic properties to PR toxin is the substitution/oxidation of functional hydroxyl group (-OH to aldehyde group (-CHO. The rapid conversion of PR toxin to the other derivatives such as PR imine, PR amide, and PR acid, based on conditions available reflects their unstability and degradative aspects. Since the PR toxin-induced toxicity could not be eliminated safely, the assessment of dose-response and other pharmacological aspects for its safe consumption is indispensable. The present review describes the natural occurrences, diversity, biosynthesis

  9. Proteome analysis of Aspergillus fumigatus identifies glycosylphosphatidylinositol-anchored proteins associated to the cell wall biosynthesis.

    Science.gov (United States)

    Bruneau, J M; Magnin, T; Tagat, E; Legrand, R; Bernard, M; Diaquin, M; Fudali, C; Latgé, J P

    2001-08-01

    Previous studies in Aspergillus fumigatus (Mouyna I., Fontaine T., Vai M., Monod M., Fonzi W. A., Diaquin M., Popolo L., Hartland R. P., Latgé J.-P, J. Biol. Chem. 2000, 275, 14882-14889) have shown that a glucanosyltransferase playing an important role in fungal cell wall biosynthesis is glycosylphosphatidylinositol (GPI) anchored to the membrane. To identify other GPI-anchored proteins putatively involved in cell wall biogenesis, a proteomic analysis has been undertaken in A. fumigatus and the protein data were matched with the yeast genomic data. GPI-anchored proteins of A. fumigatus were released from membrane preparation by an endogenous GPI-phospholipase C, purified by liquid chromatography and separated by two-dimensional electrophoresis. They were characterized by their peptide mass fingerprint through matrix-assisted laser desorption/ionization-time of flight-(MALDI-TOF)-mass spectrometry and by internal amino acid sequencing. Nine GPI-anchored proteins were identified in A. fumigatus. Five of them were homologs of putatively GPI-anchored yeast proteins (Csa1p, Crh1p, Crh2p, Ecm33p, Gas1p) of unknown function but shown by gene disruption analysis to play a role in cell wall morphogenesis. In addition, a comparative study performed with chitin synthase and glucanosyl transferase mutants of A. fumigatus showed that a modification of the growth phenotype seen in these mutants was associated to an alteration of the pattern of GPI-anchored proteins. These results suggest that GPI-anchored proteins identified in this study are involved in A. fumigatus cell wall organization.

  10. PR Toxin - Biosynthesis, Genetic Regulation, Toxicological Potential, Prevention and Control Measures: Overview and Challenges.

    Science.gov (United States)

    Dubey, Manish K; Aamir, Mohd; Kaushik, Manish S; Khare, Saumya; Meena, Mukesh; Singh, Surendra; Upadhyay, Ram S

    2018-01-01

    Out of the various mycotoxigenic food and feed contaminant, the fungal species belonging to Penicillium genera, particularly Penicillium roqueforti is of great economic importance, and well known for its crucial role in the manufacturing of Roquefort and Gorgonzola cheese. The mycotoxicosis effect of this mold is due to secretion of several metabolites, of which PR toxin is of considerable importance, with regard to food quality and safety challenges issues. The food products and silages enriched with PR toxin could lead into damage to vital internal organs, gastrointestinal perturbations, carcinogenicity, immunotoxicity, necrosis, and enzyme inhibition. Moreover, it also has the significant mutagenic potential to disrupt/alter the crucial processes like DNA replication, transcription, and translation at the molecular level. The high genetic diversities in between the various strains of P. roqueforti persuaded their nominations with Protected Geographical Indication (PGI), accordingly to the cheese type, they have been employed. Recently, the biosynthetic mechanism and toxicogenetic studies unraveled the role of ari1 and prx gene clusters that cross-talk with the synthesis of other metabolites or involve other cross-regulatory pathways to negatively regulate/inhibit the other biosynthetic route targeted for production of a strain-specific metabolites. Interestingly, the chemical conversion that imparts toxic properties to PR toxin is the substitution/oxidation of functional hydroxyl group (-OH) to aldehyde group (-CHO). The rapid conversion of PR toxin to the other derivatives such as PR imine, PR amide, and PR acid, based on conditions available reflects their unstability and degradative aspects. Since the PR toxin-induced toxicity could not be eliminated safely, the assessment of dose-response and other pharmacological aspects for its safe consumption is indispensable. The present review describes the natural occurrences, diversity, biosynthesis, genetics

  11. PR Toxin – Biosynthesis, Genetic Regulation, Toxicological Potential, Prevention and Control Measures: Overview and Challenges

    Science.gov (United States)

    Dubey, Manish K.; Aamir, Mohd; Kaushik, Manish S.; Khare, Saumya; Meena, Mukesh; Singh, Surendra; Upadhyay, Ram S.

    2018-01-01

    Out of the various mycotoxigenic food and feed contaminant, the fungal species belonging to Penicillium genera, particularly Penicillium roqueforti is of great economic importance, and well known for its crucial role in the manufacturing of Roquefort and Gorgonzola cheese. The mycotoxicosis effect of this mold is due to secretion of several metabolites, of which PR toxin is of considerable importance, with regard to food quality and safety challenges issues. The food products and silages enriched with PR toxin could lead into damage to vital internal organs, gastrointestinal perturbations, carcinogenicity, immunotoxicity, necrosis, and enzyme inhibition. Moreover, it also has the significant mutagenic potential to disrupt/alter the crucial processes like DNA replication, transcription, and translation at the molecular level. The high genetic diversities in between the various strains of P. roqueforti persuaded their nominations with Protected Geographical Indication (PGI), accordingly to the cheese type, they have been employed. Recently, the biosynthetic mechanism and toxicogenetic studies unraveled the role of ari1 and prx gene clusters that cross-talk with the synthesis of other metabolites or involve other cross-regulatory pathways to negatively regulate/inhibit the other biosynthetic route targeted for production of a strain-specific metabolites. Interestingly, the chemical conversion that imparts toxic properties to PR toxin is the substitution/oxidation of functional hydroxyl group (-OH) to aldehyde group (-CHO). The rapid conversion of PR toxin to the other derivatives such as PR imine, PR amide, and PR acid, based on conditions available reflects their unstability and degradative aspects. Since the PR toxin-induced toxicity could not be eliminated safely, the assessment of dose-response and other pharmacological aspects for its safe consumption is indispensable. The present review describes the natural occurrences, diversity, biosynthesis, genetics

  12. The Role of Amino Acid Permeases and Tryptophan Biosynthesis in Cryptococcus neoformans Survival.

    Directory of Open Access Journals (Sweden)

    João Daniel Santos Fernandes

    Full Text Available Metabolic diversity is an important factor during microbial adaptation to different environments. Among metabolic processes, amino acid biosynthesis has been demonstrated to be relevant for survival for many microbial pathogens, whereas the association between pathogenesis and amino acid uptake and recycling are less well-established. Cryptococcus neoformans is an opportunistic fungal pathogen with many habitats. As a result, it faces frequent metabolic shifts and challenges during its life cycle. Here we studied the C. neoformans tryptophan biosynthetic pathway and found that the pathway is essential. RNAi indicated that interruptions in the biosynthetic pathway render strains inviable. However, auxotroph complementation can be partially achieved by tryptophan uptake when a non preferred nitrogen source and lower growth temperature are applied, suggesting that amino acid permeases may be the target of nitrogen catabolism repression (NCR. We used bioinformatics to search for amino acid permeases in the C. neoformans and found eight potential global permeases (AAP1 to AAP8. The transcriptional profile of them revealed that they are subjected to regulatory mechanisms which are known to respond to nutritional status in other fungi, such as (i quality of nitrogen (Nitrogen Catabolism Repression, NCR and carbon sources (Carbon Catabolism Repression, CCR, (ii amino acid availability in the extracellular environment (SPS-sensing and (iii nutritional deprivation (Global Amino Acid Control, GAAC. This study shows that C. neoformans has fewer amino acid permeases than other model yeasts, and that these proteins may be subjected to complex regulatory mechanisms. Our data suggest that the C. neoformans tryptophan biosynthetic pathway is an excellent pharmacological target. Furthermore, inhibitors of this pathway cause Cryptococcus growth arrest in vitro.

  13. FUNCTIONAL SPECIALIZATION OF DUPLICATED FLAVONOID BIOSYNTHESIS GENES IN WHEAT

    Directory of Open Access Journals (Sweden)

    Khlestkina E.

    2012-08-01

    Full Text Available Gene duplication followed by subfunctionalization and neofunctionalization is of a great evolutionary importance. In plant genomes, duplicated genes may result from either polyploidization (homoeologous genes or segmental chromosome duplications (paralogous genes. In allohexaploid wheat Triticum aestivum L. (2n=6x=42, genome BBAADD, both homoeologous and paralogous copies were found for the regulatory gene Myc encoding MYC-like transcriptional factor in the biosynthesis of flavonoid pigments, anthocyanins, and for the structural gene F3h encoding one of the key enzymes of flavonoid biosynthesis, flavanone 3-hydroxylase. From the 5 copies (3 homoeologous and 2 paralogous of the Myc gene found in T. aestivum, only one plays a regulatory role in anthocyanin biosynthesis, interacting complementary with another transcriptional factor (MYB-like to confer purple pigmentation of grain pericarp in wheat. The role and functionality of the other 4 copies of the Myc gene remain unknown. From the 4 functional copies of the F3h gene in T. aestivum, three homoeologues have similar function. They are expressed in wheat organs colored with anthocyanins or in the endosperm, participating there in biosynthesis of uncolored flavonoid substances. The fourth copy (the B-genomic paralogue is transcribed neither in wheat organs colored with anthocyanins nor in seeds, however, it’s expression has been noticed in roots of aluminium-stressed plants, where the three homoeologous copies are not active. Functional diversification of the duplicated flavonoid biosynthesis genes in wheat may be a reason for maintenance of the duplicated copies and preventing them from pseudogenization.The study was supported by RFBR (11-04-92707. We also thank Ms. Galina Generalova for technical assistance.

  14. Potential of small-molecule fungal metabolites in antiviral chemotherapy.

    Science.gov (United States)

    Roy, Biswajit G

    2017-08-01

    Various viral diseases, such as acquired immunodeficiency syndrome, influenza, and hepatitis, have emerged as leading causes of human death worldwide. Scientific endeavor since invention of DNA-dependent RNA polymerase of pox virus in 1967 resulted in better understanding of virus replication and development of various novel therapeutic strategies. Despite considerable advancement in every facet of drug discovery process, development of commercially viable, safe, and effective drugs for these viruses still remains a big challenge. Decades of intense research yielded a handful of natural and synthetic therapeutic options. But emergence of new viruses and drug-resistant viral strains had made new drug development process a never-ending battle. Small-molecule fungal metabolites due to their vast diversity, stereochemical complexity, and preapproved biocompatibility always remain an attractive source for new drug discovery. Though, exploration of therapeutic importance of fungal metabolites has started early with discovery of penicillin, recent prediction asserted that only a small percentage (5-10%) of fungal species have been identified and much less have been scientifically investigated. Therefore, exploration of new fungal metabolites, their bioassay, and subsequent mechanistic study bears huge importance in new drug discovery endeavors. Though no fungal metabolites so far approved for antiviral treatment, many of these exhibited high potential against various viral diseases. This review comprehensively discussed about antiviral activities of fungal metabolites of diverse origin against some important viral diseases. This also highlighted the mechanistic details of inhibition of viral replication along with structure-activity relationship of some common and important classes of fungal metabolites.

  15. A parts list for fungal cellulosomes revealed by comparative genomics

    Energy Technology Data Exchange (ETDEWEB)

    Haitjema, Charles H.; Gilmore, Sean P.; Henske, John K.; Solomon, Kevin V.; de Groot, Randall; Kuo, Alan; Mondo, Stephen J.; Salamov, Asaf A.; LaButti, Kurt; Zhao, Zhiying; Chiniquy, Jennifer; Barry, Kerrie; Brewer, Heather M.; Purvine, Samuel O.; Wright, Aaron T.; Hainaut, Matthieu; Boxma, Brigitte; van Alen, Theo; Hackstein, Johannes H. P.; Henrissat, Bernard; Baker, Scott E.; Grigoriev, Igor V.; O' Malley, Michelle A.

    2017-05-26

    Cellulosomes are large, multi-protein complexes that tether plant biomass degrading enzymes together for improved hydrolysis1. These complexes were first described in anaerobic bacteria where species specific dockerin domains mediate assembly of enzymes onto complementary cohesin motifs interspersed within non-catalytic protein scaffolds1. The versatile protein assembly mechanism conferred by the bacterial cohesin-dockerin interaction is now a standard design principle for synthetic protein-scale pathways2,3. For decades, analogous structures have been reported in the early branching anaerobic fungi, which are known to assemble by sequence divergent non-catalytic dockerin domains (NCDD)4. However, the enzyme components, modular assembly mechanism, and functional role of fungal cellulosomes remain unknown5,6. Here, we describe the comprehensive set of proteins critical to fungal cellulosome assembly, including novel, conserved scaffolding proteins unique to the Neocallimastigomycota. High quality genomes of the anaerobic fungi Anaeromyces robustus, Neocallimastix californiae and Piromyces finnis were assembled with long-read, single molecule technology to overcome their repeat-richness and extremely low GC content. Genomic analysis coupled with proteomic validation revealed an average 320 NCDD-containing proteins per fungal strain that were overwhelmingly carbohydrate active enzymes (CAZymes), with 95 large fungal scaffoldins identified across 4 genera that contain a conserved amino acid sequence repeat that binds to NCDDs. Fungal dockerin and scaffoldin domains have no similarity to their bacterial counterparts, yet several catalytic domains originated via horizontal gene transfer with gut bacteria. Though many catalytic domains are shared with bacteria, the biocatalytic activity of anaerobic fungi is expanded by the inclusion of GH3, GH6, and GH45 enzymes in the enzyme complexes. Collectively, these findings suggest that the fungal cellulosome is an evolutionarily

  16. Fungal diversity associated with Hawaiian Drosophila host plants.

    Directory of Open Access Journals (Sweden)

    Brian S Ort

    Full Text Available Hawaiian Drosophila depend primarily, sometimes exclusively, on specific host plants for oviposition and larval development, and most specialize further on a particular decomposing part of that plant. Differences in fungal community between host plants and substrate types may establish the basis for host specificity in Hawaiian Drosophila. Fungi mediate decomposition, releasing plant micronutrients and volatiles that can indicate high quality substrates and serve as cues to stimulate oviposition. This study addresses major gaps in our knowledge by providing the first culture-free, DNA-based survey of fungal diversity associated with four ecologically important tree genera in the Hawaiian Islands. Three genera, Cheirodendron, Clermontia, and Pisonia, are important host plants for Drosophila. The fourth, Acacia, is not an important drosophilid host but is a dominant forest tree. We sampled fresh and rotting leaves from all four taxa, plus rotting stems from Clermontia and Pisonia. Based on sequences from the D1/D2 domain of the 26S rDNA gene, we identified by BLAST search representatives from 113 genera in 13 fungal classes. A total of 160 operational taxonomic units, defined on the basis of ≥97% genetic similarity, were identified in these samples, but sampling curves show this is an underestimate of the total fungal diversity present on these substrates. Shannon diversity indices ranged from 2.0 to 3.5 among the Hawaiian samples, a slight reduction compared to continental surveys. We detected very little sharing of fungal taxa among the substrates, and tests of community composition confirmed that the structure of the fungal community differed significantly among the substrates and host plants. Based on these results, we hypothesize that fungal community structure plays a central role in the establishment of host preference in the Hawaiian Drosophila radiation.

  17. Primary renal candidiasis: fungal mycetomas in the kidney

    International Nuclear Information System (INIS)

    Morris, B.S.; Chudgar, P.D.; Manejwala, O.

    2002-01-01

    Fungal infections of the urinary tract have a predilection for drainage structures rather than for the renal parenchyma. Of the causal factors, diabetes mellitus, immunosuppressed states, AIDS and prematurity are those most commonly encountered. The case of a young, diabetic man whose chief clinical presentation was dysuria is described. On further examination he was found to harbour fungal balls in the right kidney. Radiological manifestations of acute pyelonephritis were also present. Although primary renal candidiasis is often commensurate with systemic fungaemia, he displayed none of the clinical features of disseminate infection and, hence, was treated conservatively with oral antifungal agents. Fortuitously, spontaneous passage of fungal particulate matter in urine was later reported. A significant increase in the incidence of fungal cystitis has been found in recent years; however, the patient presents with many non-specific features of cystitis. Both sonography and CT show thickening of the bladder wall but, again, this lacks specificity. In the rare instance of prostate involvement, low attenuation foci on CT are seen within the gland. Despite the existence of a large number of fungal species, only a few are pathogenic to humans. Of those that cause disease in the urinary tract, Candida albicans is the most frequently encountered. A highly characteristic finding in such infections is of fungal balls, which are made up of aggregates of mycelia. However, care should be exercised in interpretation as a host of other conditions can mimic fungal bezoars. Although a CT scan at initial examination may qualify as the more descriptive, sonography provides a serial non-invasive means of evaluating the urinary tract. When in doubt, a urine culture clinches the diagnosis. Copyright (2002) Blackwell Science Pty Ltd

  18. Conjunctival bacterial and fungal flora in clinically normal sheep.

    Science.gov (United States)

    Bonelli, Francesca; Barsotti, Giovanni; Attili, Anna Rita; Mugnaini, Linda; Cuteri, Vincenzo; Preziuso, Silvia; Corazza, Michele; Preziuso, Giovanna; Sgorbini, Micaela

    2014-01-01

    The aim was to identify conjunctival bacterial and fungal flora in clinically normal sheep. Prospective study. Tuscany. 100 eyes from 50 adult Massese female sheep were examined. The sheep included in the study were considered free of anterior ophthalmic abnormalities. Bacteria were identified by morphological assessment, Gram staining, biochemical tests. Identification of filamentous fungi was achieved at the genus level, and Aspergillus species were identified based on keys provided by other authors. Yeast colonies were highlighted, but not identified. Positive cultures were obtained from 100/100 eyes for bacteria, and from 86/100 eyes for fungi. A total of 14 types of bacteria and 5 types of fungi were isolated. Yeasts were isolated from 13/100 eyes. The most frequent fungal isolates were saprophytic fungi. Conjunctival bacterial and fungal flora of clinically normal eyes were reported in sheep. The positivity obtained for conjunctival bacteria was higher compared to findings in the literature by other authors in the same species (100 per cent v 40 per cent), while our results were in line with a recent work performed on mouflons (Ovis Musimon) with a 100 per cent positivity for bacterial conjunctival fornix. In our survey, Gram-positive species were prevalent, as reported by other authors in different species. Few data are available in the literature regarding conjunctival fungal flora in healthy small ruminants. The prevalence of conjunctival fungal flora in this study was higher than findings reported in mouflons (86 per cent v 45 per cent). Differences in fungal prevalence may be due to different methods of managing herds, though further studies are required to verify this hypothesis. The similarities in bacterial and fungal isolates between sheep and mouflons suggest a genera pattern of conjunctival colonisation by bacteria and fungi.

  19. Identification of fungal causative agents of rhinosinusitis from Mashhad, Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Javad Najafzadeh

    2017-09-01

    Full Text Available Background and Purpose: Rhinosinusitis is a common disorder, influencing approximately 20% of the population at some time of their lives. It was recognized and reported with expanding recurrence over the past two decades worldwide. Undoubtedly, correct diagnosis of fungi in patients with fungal rhinosinusitis affects the treatment planning and prognosis of the patients. Identification of the causative agents using the standard mycological procedures remains difficult and time-consuming. Materials and Methods: Based on clinical and radiological parameters, 106 patients suspected of fungal rhinosinusitis were investigated in this cross-sectional prospective study from April 2012 to March 2016 at an otorhinolaryngology department. In this study, internal transcribed spacer (ITS and calmodulin (CaM sequencing were respectively validated as reliable techniques for the identification of Mucorales and Aspergillus to species level (both agents of fungal rhinosinusitis. Results: Of these, 63 (59.4% patients were suspected of allergic fungal rhinosinusitis (AFRS, 40 (37.7% patients suspected of acute invasive fungal rhinosinusitis (AIFRS, and 3 (2.8% patients suspected of fungus ball. In patients suspected of AFRS, AIFRS, and fungus ball only 7, 29, and 1 had positive fungal culture, respectively. After ITS and CaM sequencing, Aspergillus flavus was the most common species isolated from non-invasive forms, and A. flavus and Rhizopus oryzae were more frequently isolated from invasive forms. Conclusion: Aspergillus flavus is the most common agent of fungal rhinosinusitis in Iran, unlike most other reports from throughout the world stating that A. fumigatus is the most frequent causative agent of this disease.

  20. Spectrum of fungal keratitis:clinicopathologic study of 44 cases

    Directory of Open Access Journals (Sweden)

    Rajpal Singh Punia

    2014-02-01

    Full Text Available AIM:To determine the causative agents of fungal keratitis and study the predisposing factors over a period of ten years in a single tertiary care hospital.METHODS:A retrospective analysis of fungal corneal ulcers was done from 2003-2012. Patients’ clinical data were noted from the file records. Correlation of histopathological diagnosis was done with the report on fungal culture.RESULTS: Mycotic keratitis was established in 44 cases by a positive fungal culture. Direct microscopic examination of potassium hydroxide (KOH mounts revealed fungal elements in 39 cases while 40 cases showed fungus on Gram stained smears. Males (54.55% were more commonly affected than the females (45.45%. The age ranged from 18 to 82 years. Most common age group to be involved was 41-60 years. Predisposing risk factors were seen in 34 (77.27% cases. Most common findings on clinical examination were anterior chamber reaction and conjunctival injection seen in all the cases. Other common findings were stromal infiltration and hypopyon seen in 20 (45.45% and 18 (40.91% cases respectively. On histopathological examination the fungus was typed, as aspergillus in 34 cases while no definite typing was possible in 10 cases. The predominant isolate was aspergillus flavus (59.09% followed by fusarium (15.91%. Mixed fungal and bacterial infection was seen in 3 (6.82% cases.CONCLUSION:Although culture is the gold standard for definitive diagnosis of fungal keratitis, direct microscopic examination of corneal scrapings or histomorphological evaluation of biopsies allow a rapid preliminary diagnosis. Early administration of antifungal treatment helps in preventing dreadful complications.

  1. Epidemiology of fungal infections and risk factors in newborn patients

    Directory of Open Access Journals (Sweden)

    Paolo Manzoni

    2013-07-01

    Full Text Available The incidence of fungal infections among newborn babies is increasing, owing mainly to the in­creased ability to care and make survive immature infants at higher specific risk for fungal infections. The risk is higher in infants with very low and extremely low birth weight, in babies receiving total parenteral nutrition, in neonates with limited barrier effect in the gut, or with central venous catheter or other devices where fungal biofilms can originate. Also neonates receiving broad spectrum antibiotics, born through caesarian section or non-breastfed can feature an increased, specific risk. Most fungal infections in neonatology occur in premature children, are of nosocomial origin, and are due to Candida species. Colonization is a preliminary step, and some factors must be considered for the diagnosis and grading process: the iso­lation site, the number of colonized sites, the intensity of colonization, and the Candida subspecies. The most complicated patients are at greater risk of fungal infections, and prophylaxis or pre-emptive therapy should often be considered. A consistent decisional tree in neonatology is yet to be defined, but some efforts have been made in order to identify characteristics that should guide the prophylaxis or treatment choices. A negative blood culture and the absence of symptoms aren’t enough to rule out the diagnosis of fungal infections in newborn babies. Similarly, laboratory tests have been validated only for adults. The clinical judgement is of utmost importance in the diagnostic process, and should take into account the presence of clinical signs of infection, of a severe clinical deterioration, as well as changes in some laboratory tests, and also the presence and characteristics of a pre-existing fungal colonization.http://dx.doi.org/10.7175/rhc.v14i1S.856

  2. Fungal delignification of lignocellulosic biomass improves the saccharification of cellulosics.

    Science.gov (United States)

    Gupta, Rishi; Mehta, Girija; Khasa, Yogender Pal; Kuhad, Ramesh Chander

    2011-07-01

    The biological delignification of lignocellulosic feedstocks, Prosopis juliflora and Lantana camara was carried out with Pycnoporus cinnabarinus, a white rot fungus, at different scales under solid-state fermentation (SSF) and the fungal treated substrates were evaluated for their acid and enzymatic saccharification. The fungal fermentation at 10.0 g substrate level optimally delignified the P. juliflora by 11.89% and L. camara by 8.36%, and enriched their holocellulose content by 3.32 and 4.87%, respectively, after 15 days. The fungal delignification when scaled up from 10.0 g to 75.0, 200.0 and 500.0 g substrate level, the fungus degraded about 7.69-10.08% lignin in P. juliflora and 6.89-7.31% in L. camara, and eventually enhanced the holocellulose content by 2.90-3.97 and 4.25-4.61%, respectively. Furthermore, when the fungal fermented L. camara and P. juliflora was hydrolysed with dilute sulphuric acid, the sugar release was increased by 21.4-42.4% and the phenolics content in hydrolysate was decreased by 18.46 and 19.88%, as compared to the unfermented substrate acid hydrolysis, respectively. The reduction of phenolics in acid hydrolysates of fungal treated substrates decreased the amount of detoxifying material (activated charcoal) by 25.0-33.0% as compared to the amount required to reduce almost the same level of phenolics from unfermented substrate hydrolysates. Moreover, an increment of 21.1-25.1% sugar release was obtained when fungal treated substrates were enzymatically hydrolysed as compared to the hydrolysis of unfermented substrates. This study clearly shows that fungal delignification holds potential in utilizing plant residues for the production of sugars and biofuels.

  3. Biosynthesis of oligosaccharides and fructans in Agave vera cruz : Part III - Biosynthesis of fructans

    Energy Technology Data Exchange (ETDEWEB)

    Satyanarayana, M N [Central Food Technological Research Inst., Mysore (India). Dept. of Biochemistry

    1976-12-01

    Evidence has been obtained for the biosynthesis of 'fructans' in Agave vera cruz. A hydrolase-free enzyme preparation from the stem juice with U-/sup 14/C sucrose as substrate and the native fructan as primer leads to incorporation of /sup 14/C fructose into a polymer like compound. This inference is based on criteria such as the chromatographic mobility of the product and the elution volume from a Sephadex G-25 column. Two optimum pHs 4.9 and 6.1 and optimum temperature 377degC are observed for the reaction. The activity is dependent on primer, enzyme, substrate concentration and duration of incubation. The ratio of substrate to primer appears to be a special factor; higher ratios retard synthesis (S:P 5:1, 1.14%, S:P 100:1, 0.36% incorporation), while lower ones enhance (reaching a maximum of 11.35% at an S:P ratio of 1.75 in hr). Inulin in place of the native fructan is less efficient as primer. Each of the higher homologues of sucrose, tri to hexasaccharides (tested so far), leads to fructan formation with elution volumes from a Sephadex G-25 column close to that of the primer. U-/sup 14/C fructose or glucose in place of U-/sup 14/C sucrose or absence of enzyme leads to no incorporation. Sucrose seems to have a key role both in the initiation and lengthening of the fructan chain.

  4. Aspergillus niger Enhance Bioactive Compounds Biosynthesis As Well As Expression of Functional Genes in Adventitious Roots of Glycyrrhiza uralensis Fisch.

    Science.gov (United States)

    Li, Jing; Wang, Juan; Li, Jinxin; Liu, Dahui; Li, Hongfa; Gao, Wenyuan; Li, Jianli; Liu, Shujie

    2016-02-01

    In the present study, the culture conditions for the accumulation of Glycyrrhiza uralensis adventitious root metabolites in balloon-type bubble bioreactors (BTBBs) have been optimized. The results of the culture showed that the best culture conditions were a cone angle of 90° bioreactor and 0.4-0.6-0.4-vvm aeration volume. Aspergillus niger can be used as a fungal elicitor to enhance the production of defense compounds in plants. With the addition of a fungal elicitor (derived from Aspergillus niger), the maximum accumulation of total flavonoids (16.12 mg g(-1)) and glycyrrhetinic acid (0.18 mg g(-1)) occurred at a dose of 400 mg L(-1) of Aspergillus niger resulting in a 3.47-fold and 1.8-fold increase over control roots. However, the highest concentration of polysaccharide (106.06 mg g(-1)) was achieved with a mixture of elicitors (Aspergillus niger and salicylic acid) added to the medium, resulting in a 1.09-fold increase over Aspergillus niger treatment alone. Electrospray ionization tandem mass spectrometry (ESI-MS(n)) analysis was performed, showing that seven compounds were present after treatment with the elicitors, including uralsaponin B, licorice saponin B2, liquiritin, and (3R)-vestitol, only identified in the mixed elicitor treatment group. It has also been found that elicitors (Aspergillus niger and salicylic acid) significantly upregulated the expression of the cinnamate 4-hydroxylase (C4H), β-amyrin synthase (β-AS), squalene epoxidase (SE) and a cytochrome P450 monooxygenase (CYP72A154) genes, which are involved in the biosynthesis of bioactive compounds, and increased superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) activity.

  5. Increased sesquiterpenoid biosynthesis and an apparent decrease in sterol biosynthesis in elicitor-treated tobacco cell suspension cultures

    International Nuclear Information System (INIS)

    Voegeli, U.; Bhatt, P.N.; Chappell, J.

    1987-01-01

    Addition of fungel elicitor prepared from Phytophthora parasitica to tobacco cell suspension cultures leads to an increased production of the phytoalexin capsidiol. Capsidiol is a sesquiterpenoid which is most likely synthesized from farnesylpyrophosphat (FPP) by a bicyclic cyclase reaction. Because FPP is also a substrate for squalene synthetase and therefore a precursor of sterol biosynthesis, the question arises whether or not the accumulation of capsidiol in elicitor-treated cells occurs at the expense of sterol biosynthesis. ( 14 C]-acetate was given to elicitor-treated and control (no treatment) cell cultures and incorporation into sterols and capsidiol determined. No labeled capsidiol was detected in control cells. In elicitor-treated cells about 12-15% of the radioactivity taken up by the cells was incorporated into capsidiol. In contrast, control cells incorporated 4 times more radioactivity into sterols than elicitor-treated cells. Similar results were obtained using ( 3 H)-mevalonate as a precursor of capsidiol and sterol biosynthesis. Likely explanations for the apparently decline in sterol biosynthesis in elicitor-treated cells include: (1) inhibition of squalene synthetase; (2) induction of capsidiol synthesizing enzymes; and (3) metabolic channeling of FPP into capsidiol versus sterols. These possibilities will be discussed further together with other results

  6. Regulatory cross-talks and cascades in rice hormone biosynthesis pathways contribute to stress signaling

    Directory of Open Access Journals (Sweden)

    Arindam Deb

    2016-08-01

    Full Text Available Crosstalk among different hormone signaling pathways play an important role in modulating plant response to both biotic and abiotic stress. Hormone activity is controlled by its bio-availability, which is again influenced by its biosynthesis. Thus independent hormone biosynthesis pathways must be regulated and co-ordinated to mount an integrated response. One of the possibilities is to use cis-regulatory elements to orchestrate expression of hormone biosynthesis genes. Analysis of CREs, associated with differentially expressed hormone biosynthesis related genes in rice leaf under Magnaporthe oryzae attack and drought stress enabled us to obtain insights about cross-talk among hormone biosynthesis pathways at the transcriptional level. We identified some master transcription regulators that co-ordinate different hormone biosynthesis pathways under stress. We found that Abscisic acid and Brassinosteroid regulate Cytokinin conjugation; conversely Brassinosteroid biosynthesis is affected by both Abscisic acid and Cytokinin. Jasmonic acid and Ethylene biosynthesis may be modulated by Abscisic acid through DREB transcription factors. Jasmonic acid or Salicylic acid biosynthesis pathways are co-regulated but they are unlikely to influence each other’s production directly. Thus multiple hormones may modulate hormone biosynthesis pathways through a complex regulatory network, where biosynthesis of one hormone is affected by several other contributing hormones.

  7. Fungal degradation of coal as a pretreatment for methane production

    Science.gov (United States)

    Haider, Rizwan; Ghauri, Muhammad A.; SanFilipo, John R.; Jones, Elizabeth J.; Orem, William H.; Tatu, Calin A.; Akhtar, Kalsoom; Akhtar, Nasrin

    2013-01-01

    Coal conversion technologies can help in taking advantage of huge low rank coal reserves by converting those into alternative fuels like methane. In this regard, fungal degradation of coal can serve as a pretreatment step in order to make coal a suitable substrate for biological beneficiation. A fungal isolate MW1, identified as Penicillium chrysogenum on the basis of fungal ITS sequences, was isolated from a core sample of coal, taken from a well drilled by the US. Geological Survey in Montana, USA. The low rank coal samples, from major coal fields of Pakistan, were treated with MW1 for 7 days in the presence of 0.1% ammonium sulfate as nitrogen source and 0.1% glucose as a supplemental carbon source. Liquid extracts were analyzed through Excitation–Emission Matrix Spectroscopy (EEMS) to obtain qualitative estimates of solubilized coal; these analyses indicated the release of complex organic functionalities. In addition, GC–MS analysis of these extracts confirmed the presence of single ring aromatics, polyaromatic hydrocarbons (PAHs), aromatic nitrogen compounds and aliphatics. Subsequently, the released organics were subjected to a bioassay for the generation of methane which conferred the potential application of fungal degradation as pretreatment. Additionally, fungal-mediated degradation was also prospected for extracting some other chemical entities like humic acids from brown coals with high huminite content especially from Thar, the largest lignite reserve of Pakistan.

  8. Friends or foes? Emerging insights from fungal interactions with plants.

    Science.gov (United States)

    Zeilinger, Susanne; Gupta, Vijai K; Dahms, Tanya E S; Silva, Roberto N; Singh, Harikesh B; Upadhyay, Ram S; Gomes, Eriston Vieira; Tsui, Clement Kin-Ming; Nayak S, Chandra

    2016-03-01

    Fungi interact with plants in various ways, with each interaction giving rise to different alterations in both partners. While fungal pathogens have detrimental effects on plant physiology, mutualistic fungi augment host defence responses to pathogens and/or improve plant nutrient uptake. Tropic growth towards plant roots or stomata, mediated by chemical and topographical signals, has been described for several fungi, with evidence of species-specific signals and sensing mechanisms. Fungal partners secrete bioactive molecules such as small peptide effectors, enzymes and secondary metabolites which facilitate colonization and contribute to both symbiotic and pathogenic relationships. There has been tremendous advancement in fungal molecular biology, omics sciences and microscopy in recent years, opening up new possibilities for the identification of key molecular mechanisms in plant-fungal interactions, the power of which is often borne out in their combination. Our fragmentary knowledge on the interactions between plants and fungi must be made whole to understand the potential of fungi in preventing plant diseases, improving plant productivity and understanding ecosystem stability. Here, we review innovative methods and the associated new insights into plant-fungal interactions. © FEMS 2015.

  9. Dynamics of fungal colonization in a new medical mycology laboratory.

    Science.gov (United States)

    Sautour, M; Fournel, I; Dalle, F; Calinon, C; L'Ollivier, C; Goyer, M; Cachia, C; Aho, S; Sixt, N; Vagner, O; Cuisenier, B; Bonnin, A

    2012-03-01

    Study of the spatio-temporal fungal colonization in a new medical mycology laboratory. A 17-month survey of airborne fungal contamination was conducted in a new medical mycology laboratory at a tertiary care university hospital. This survey was implemented at three different periods: before the new premises were occupied (period A), during the move into the new laboratory (period B) and after resumption of the mycological activities in these new premises (period C). During period A, the airborne fungal load ranged from 2.3 to 6 cfu/m(3). The most frequently recovered airborne fungi were Penicillium spp. (75 to 100%). During period B, a dramatic increase in Penicillium chrysogenum conidia was observed in the air of the new laboratory (40 to 160 cfu/m(3)). During period C, the fungal load ranged from 4.5 to 8.4 cfu/m(3). Penicillium was the most common genus identified in rooms of the laboratory where no filamentous fungi were handled, while Aspergillus was clearly the predominant genus (78%) in the room dedicated to the culture of filamentous fungi. We suggest that the specific fungal ecology in air of the room dedicated to the culture of filamentous fungi is due to the handling of a large number of medical strains of A. fumigatus. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  10. Fungal communities in soils along a vegetative ecotone.

    Science.gov (United States)

    Karst, Justine; Piculell, Bridget; Brigham, Christy; Booth, Michael; Hoeksema, Jason D

    2013-01-01

    We investigated the community composition and diversity of soil fungi along a sharp vegetative ecotone between coastal sage scrub (CSS) and nonnative annual grassland habitat at two sites in coastal California. USA- We pooled soil samples across 29 m transects on either side of the ecotone at each of the two sites, and. using clone libraries of fungal ribosomal DNA, we identified 280 operational taxonomic units (OTUs) from a total 40 g soil. We combined information from partial LSU and ITS sequences and found that the majority of OTUs belonged to the phylum Ascomycota, followed by Basidiomycota. Within the Ascomycota. a quarter of OTUs were Sordariomycetes. 17% were Leotiomycet.es, 16% were Dothideomycetes and the remaining OTUs were distributed among the classes Eurotiomycetes, Pezizomycetes, Lecanoromycetes, Orbiliomycetes and Arthoniomycetes. Within the Basidiomycota. all OTUs but one belonged to the subphylum Agaricomycotina. We also sampled plant communities at the same sites to offer a point of comparison for patterns in richness of fungal communities. Fungal communities had higher alpha and beta diversity than plant communities; fungal communities were approximately 20 times as rich as plant communities and the majority of OTUs were found in single soil samples. Soils harbored a unique mycoflora that did not reveal vegetative boundaries or site differences. High alpha and beta diversity and possible sampling artifacts necessitate extensive sampling to reveal differentiation in these fungal communities.

  11. CNS fungal meningitis to the "Top of the basilar"

    Institute of Scientific and Technical Information of China (English)

    Logan CS; Kirschner RC; Simonds GR

    2013-01-01

    Central nervous system(CNS) infections are a rare complication of epidural steroid injections and without strong clinical suspicion, fungal organisms may be overlooked among the long differential of causes of meningitis.Rare sequela of fungal meningitis is the development of stroke.To our knowledge, we present the first case of post epidural steroid injection(ESI) fungal meningitis leading toa basilar artery stroke, otherwise known as“top of the basilar” syndrome.We present a49-year-old female with a history ofESIs who presented to the emergency department with headache, neck stiffness, and abdominal pain.She was discharged after her labs and symptoms were deemed inconsistent with meningitis.She was eventually admitted and twelve days after her originalED visit, she was diagnosed with meningitis and started on anti-fungal treatment.She was discharged88 days later but was readmitted due to left sided weakness and mental status changes.She quickly lost motor and bulbar functions.AnMRA showed diminished distal flow through the basilar artery, suggesting near complete occlusion.Although appropriate long term anti-fungal treatment was started, the patient still succumbed to a rare vascular event.Physicians who are treating patients forESI meningitis should be aware of the potential for vasculitic and encephalitic complications.

  12. Endophytic Fungal Diversity in Medicinal Plants of Western Ghats, India

    Directory of Open Access Journals (Sweden)

    Monnanda Somaiah Nalini

    2014-01-01

    Full Text Available Endophytes constitute an important component of microbial diversity, and in the present investigation, seven plant species with rich ethnobotanical uses representing six families were analyzed for the presence of endophytic fungi from their natural habitats during monsoon (May/June and winter (November/December seasons of 2007. Fungal endophytes were isolated from healthy plant parts such as stem, root, rhizome, and inflorescence employing standard isolation methods. One thousand five hundred and twenty-nine fungal isolates were obtained from 5200 fragments. Stem fragments harbored more endophytes (80.37% than roots (19.22%. 31 fungal taxa comprised of coelomycetes (65%, hyphomycetes (32%, and ascomycetes (3%. Fusarium, Acremonium, Colletotrichum, Chaetomium, Myrothecium, Phomopsis, and Pestalotiopsis spp. were commonly isolated. Diversity indices differed significantly between the seasons (P<0.001. Species richness was greater for monsoon isolations than winter. Host specificity was observed for few fungal endophytes. UPGMA cluster analysis grouped the endophytes into distinct clusters on the basis of genetic distance. This study is the first report on the diversity and host-specificity of endophytic fungal taxa were from the semi evergreen forest type in Talacauvery subcluster of Western Ghats.

  13. Fermented whey as poultry feed additive to prevent fungal contamination.

    Science.gov (United States)

    Londero, Alejandra; León Peláez, María A; Diosma, Gabriela; De Antoni, Graciela L; Abraham, Analía G; Garrote, Graciela L

    2014-12-01

    Fungal contamination of poultry feed causes economic losses to industry and represents a potential risk to animal health. The aim of the present study was to analyze the effectiveness of whey fermented with kefir grains as additive to reduce fungal incidence, thus improving feed safety. Whey fermented for 24 h at 20 °C with kefir grains (100 g L(-1) ) reduced conidial germination of Aspergillus flavus, Aspergillus parasiticus, Aspergillus terreus, Aspergillus fumigatus, Penicillium crustosum, Trichoderma longibrachiatum and Rhizopus sp. Poultry feed supplemented with fermented whey (1 L kg(-1) ) was two to four times more resistant to fungal contamination than control feed depending on the fungal species. Additionally, it contained kefir microorganisms at levels of 1 × 10(8) colony-forming units (CFU) kg(-1) of lactic acid bacteria and 6 × 10(7) CFU kg(-1) of yeasts even after 30 days of storage. Fermented whey added to poultry feed acted as a biopreservative, improving its resistance to fungal contamination and increasing its shelf life. © 2014 Society of Chemical Industry.

  14. [Preservation of high risk fungal cultures of Histoplasma and Cryptococcus].

    Science.gov (United States)

    Fernández Andreu, C Carlos Manuel; Díaz Suárez, Luis Alberto; Ilnait Zaragozi, María Teresa; Aragonés López, Carlos; Martínez Machín, Gerardo; Perurena Lancha, Mayda R

    2012-01-01

    culture collections are responsible for providing the microbial resources for development of biological sciences. Storage in distilled water is one of the easiest and least expensive method for long-term fungal preservation. to evaluate the usefulness of this preservation method in fungal culture of Histoplasma and Cryptococcus. the preservation condition of the highest biological risk species from Histoplasma y Cryptococcus genera, included in the fungal culture collection of "Pedro Kouri" Institute of Tropical Medicine in Havana, was evaluated in this study. One hundred and two strains stored in distilled water, 92% of which had been preserved for more than 10 years, were analyzed. the percentages of recovered strains from H. capsulatum, C. neoformans and C. gattii were 64.3%; 79.1% and 100% respectively. This method of preservation proved to be satisfactory for fungal culture in labs with limited financial resources. A web-based database with interesting information about the collection was made. The importance of strict compliance with the biosafety measures in these collections, particularly with high risk pathogens. preservation of fungal cultures in distilled water is a very useful method for laboratories with limited resources. Culture collections should be assumed as an essential activity in order to solve increasing challenges in the development of biomedical sciences.

  15. The burden of serious human fungal infections in Brazil.

    Science.gov (United States)

    Giacomazzi, Juliana; Baethgen, Ludmila; Carneiro, Lilian C; Millington, Maria Adelaide; Denning, David W; Colombo, Arnaldo L; Pasqualotto, Alessandro C

    2016-03-01

    In Brazil, human fungal infections are prevalent, however, these conditions are not officially reportable diseases. To estimate the burden of serious fungal diseases in 1 year in Brazil, based on available data and published literature. Historical official data from fungal diseases were collected from Brazilian Unified Health System Informatics Department (DATASUS). For fungal diseases for which no official data were available, assumptions of frequencies were made by estimating based on published literature. The incidence (/1000) of hospital admissions for coccidioidomycosis was 7.12; for histoplasmosis, 2.19; and for paracoccidioidomycosis, 7.99. The estimated number of cryptococcal meningoencephalitis cases was 6832. Also, there were 4115 cases of Pneumocystis pneumonia in AIDS patients per year, 1 010 465 aspergillosis and 2 981 416 cases of serious Candida infections, including invasive and non-invasive diseases. In this study, we demonstrate that more than 3.8 million individuals in Brazil may be suffering from serious fungal infections, mostly patients with malignant cancers, transplant recipients, asthma, previous tuberculosis, HIV infection and those living in endemic areas for truly pathogenic fungi. The scientific community and the governmental agencies should work in close collaboration in order to reduce the burden of such complex, difficult-to-diagnose and hard to treat diseases. © 2015 Blackwell Verlag GmbH.

  16. Fungal Infections in Some Economically Important Freshwater Fishes

    Directory of Open Access Journals (Sweden)

    Zafar Iqbal*, Uzma Sheikh and Rabia Mughal

    2012-06-01

    Full Text Available Aim of this study was to investigate fungal infections in four species of carps including goldfish, Carassius (C. auratus L.; silver carp, Hypophthalmichthys (H. molitrix Richardsons; rahu, Labeo (L. rohita Hamilton and Ctenopharyngodon (C. idella Valenciennes. Nine specimens of each species were studied for the presence of fungal infections. Infected fishes showed clinical signs such as fungal growth on skin, fins, eyes, eroded fins and scales, hemorrhages on body surface and abdominal distension. The specimens from infected organs of fish were inoculated on each, malt extract, Sabouraud dextrose and potato dextrose agars. The fungal colonies of white, black, green, grey and brown colors were observed in the agar plates. Slides were prepared and stained with 0.05% Trypan blue in lactophenol. C. auratus showed the highest infection rate (44.4% followed by H. molitrix and L. rohita (11.1% each. Five fungal species viz. Aspergillus (33.3%, Penicillium (22.2%, Alternaria (27.7%, Blastomyces spp (11.1% and Rhizopus (5.5% were isolated. Posterior part of the fish had significantly (P=0.05 higher (62.5% infection as compared to anterior part (37.5%. The caudal fin with 31.25% infection was the single most affected area. This study showed that most of the fungi isolated from fishes are considered as normal mycoflora, yet many fungi can cause natural infections in ponds and aquarium.

  17. Probing the Selectivity and Protein•Protein Interactions of a Non-Reducing Fungal Polyketide Synthase Using Mechanism-Based Crosslinkers

    Science.gov (United States)

    Bruegger, Joel; Haushalter, Bob; Vagstad, Anna; Shakya, Gaurav; Mih, Nathan; Townsend, Craig A.; Burkart, Michael D.; Tsai, Shiou-Chuan

    2013-01-01

    SUMMARY Protein•protein interactions, which often involve interactions between an acyl carrier protein (ACP) and its partner enzymes, are important for coordinating polyketide biosynthesis. However, the nature of such interactions is not well understood, especially in the fungal non-reducing polyketide synthases (NR-PKSs) that biosynthesize toxic and pharmaceutically important polyketides. Here, we employ a mechanism-based crosslinker to successfully probe ACP and ketosynthase (KS) domain interactions in NR-PKSs. We found that crosslinking efficiency is closely correlated with the strength of ACP•KS interactions, and that KS demonstrates strong starter unit selectivity. We further identified positively charged surface residues by KS mutagenesis, which mediate key interactions with the negatively-charged ACP surface. Such complementary/matching contact pairs can serve as “adapter surfaces” for future efforts to generate new polyketides using NR-PKSs. PMID:23993461

  18. Propiconazole-enhanced hepatic cell proliferation is associated with dysregulation of the cholesterol biosynthesis pathway leading to activation of Erk1/2 through Ras farnesylation

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, Lynea A.; Moore, Tanya; Nesnow, Stephen, E-mail: nesnow.stephen@epa.gov

    2012-04-15

    Propiconazole is a mouse hepatotumorigenic fungicide designed to inhibit CYP51, a key enzyme in the biosynthesis of ergosterol in fungi and is widely used in agriculture to prevent fungal growth. Metabolomic studies in mice revealed that propiconazole increased levels of hepatic cholesterol metabolites and bile acids, and transcriptomic studies revealed that genes within the cholesterol biosynthesis, cholesterol metabolism and bile acid biosyntheses pathways were up-regulated. Hepatic cell proliferation was also increased by propiconazole. AML12 immortalized hepatocytes were used to study propiconazole's effects on cell proliferation focusing on the dysregulation of cholesterol biosynthesis and resulting effects on Ras farnesylation and Erk1/2 activation as a primary pathway. Mevalonate, a key intermediate in the cholesterol biosynthesis pathway, increases cell proliferation in several cancer cell lines and tumors in vivo and serves as the precursor for isoprenoids (e.g. farnesyl pyrophosphate) which are crucial in the farnesylation of the Ras protein by farnesyl transferase. Farnesylation targets Ras to the cell membrane where it is involved in signal transduction, including the mitogen-activated protein kinase (MAPK) pathway. In our studies, mevalonic acid lactone (MVAL), a source of mevalonic acid, increased cell proliferation in AML12 cells which was reduced by farnesyl transferase inhibitors (L-744,832 or manumycin) or simvastatin, an HMG-CoA reductase inhibitor, indicating that this cell system responded to alterations in the cholesterol biosynthesis pathway. Cell proliferation in AML12 cells was increased by propiconazole which was reversed by co-incubation with L-744,832 or simvastatin. Increasing concentrations of exogenous cholesterol muted the proliferative effects of propiconazole and the inhibitory effects of L-733,832, results ascribed to reduced stimulation of the endogenous cholesterol biosynthesis pathway. Western blot analysis of subcellular

  19. Analysis of the Aspergillus fumigatus proteome reveals metabolic changes and the activation of the pseurotin A biosynthesis gene cluster in response to hypoxia.

    Science.gov (United States)

    Vödisch, Martin; Scherlach, Kirstin; Winkler, Robert; Hertweck, Christian; Braun, Hans-Peter; Roth, Martin; Haas, Hubertus; Werner, Ernst R; Brakhage, Axel A; Kniemeyer, Olaf

    2011-05-06

    The mold Aspergillus fumigatus is the most important airborne fungal pathogen. Adaptation to hypoxia represents an important virulence attribute for A. fumigatus. Therefore, we aimed at obtaining a comprehensive overview about this process on the proteome level. To ensure highly reproducible growth conditions, an oxygen-controlled, glucose-limited chemostat cultivation was established. Two-dimensional gel electrophoresis analysis of mycelial and mitochondrial proteins as well as two-dimensional Blue Native/SDS-gel separation of mitochondrial membrane proteins led to the identification of 117 proteins with an altered abundance under hypoxic in comparison to normoxic conditions. Hypoxia induced an increased activity of glycolysis, the TCA-cycle, respiration, and amino acid metabolism. Consistently, the cellular contents in heme, iron, copper, and zinc increased. Furthermore, hypoxia induced biosynthesis of the secondary metabolite pseurotin A as demonstrated at proteomic, transcriptional, and metabolite levels. The observed and so far not reported stimulation of the biosynthesis of a secondary metabolite by oxygen depletion may also affect the survival of A. fumigatus in hypoxic niches of the human host. Among the proteins so far not implicated in hypoxia adaptation, an NO-detoxifying flavohemoprotein was one of the most highly up-regulated proteins which indicates a link between hypoxia and the generation of nitrosative stress in A. fumigatus.

  20. Genomics reveals traces of fungal phenylpropanoid-flavonoid metabolic pathway in the f ilamentous fungus Aspergillus oryzae.

    Science.gov (United States)

    Juvvadi, Praveen Rao; Seshime, Yasuyo; Kitamoto, Katsuhiko

    2005-12-01

    Fungal secondary metabolites constitute a wide variety of compounds which either play a vital role in agricultural, pharmaceutical and industrial contexts, or have devastating effects on agriculture, animal and human affairs by virtue of their toxigenicity. Owing to their beneficial and deleterious characteristics, these complex compounds and the genes responsible for their synthesis have been the subjects of extensive investigation by microbiologists and pharmacologists. A majority of the fungal secondary metabolic genes are classified as type I polyketide synthases (PKS) which are often clustered with other secondary metabolism related genes. In this review we discuss on the significance of our recent discovery of chalcone synthase (CHS) genes belonging to the type III PKS superfamily in an industrially important fungus, Aspergillus oryzae. CHS genes are known to play a vital role in the biosynthesis of flavonoids in plants. A comparative genome analyses revealed the unique character of A. oryzae with four CHS-like genes (csyA, csyB, csyC and csyD) amongst other Aspergilli (Aspergillus nidulans and Aspergillus fumigatus) which contained none of the CHS-like genes. Some other fungi such as Neurospora crassa, Fusarium graminearum, Magnaporthe grisea, Podospora anserina and Phanerochaete chrysosporium also contained putative type III PKSs, with a phylogenic distinction from bacteria and plants. The enzymatically active nature of these newly discovered homologues is expected owing to the conservation in the catalytic residues across the different species of plants and fungi, and also by the fact that a majority of these genes (csyA, csyB and csyD) were expressed in A. oryzae. While this finding brings filamentous fungi closer to plants and bacteria which until recently were the only ones considered to possess the type III PKSs, the presence of putative genes encoding other principal enzymes involved in the phenylpropanoid and flavonoid biosynthesis (viz

  1. Radiation sensitivity of fungal microflora isolated from some pharmaceutical ingredients

    Energy Technology Data Exchange (ETDEWEB)

    Mostafa, S.A. (Ain Shams Univ., Cairo (Egypt). Botany Dept.); El-Zawahry, Y.A.; Abdel All, S.S.

    1983-01-01

    The total number of fungal microflora of D-glucose, NaCl, KCl and their solutions was determined. The fungal isolates were identified as Aspergillus fumigatus. Aspergillus niger; Spicaria divaricate and Spicaria silvatica and their response to ..gamma..-radiation was determined, the most predominant isolate Asp. fumigatus was also the most irradiation resistant. The Dio and the lethal dose were determined for each isolate in a pure spore suspension as well as in the presence of the other isolates. The higher lethal dose values obtained for pure spore suspension as compared to that obtained for the natural fungal flora a D-glucose are discussed in terms of spore clumping. The activity of amylase, protease and L-asparaginase of Asp. fumigatus was examined prior to and after exposure to different doses of ..gamma..-radiation. Though all were inhibited at high doses, the effect was not as drastic as it was on cell viability.

  2. Treatment of lingual traumatic ulcer accompanied with fungal infections

    Directory of Open Access Journals (Sweden)

    Sella Sella

    2011-09-01

    Full Text Available Background: Traumatic ulcer is a common form of ulceration occured in oral cavity caused by mechanical trauma, either acute or chronic, resulting in loss of the entire epithelium. Traumatic ulcer often occurs in children that are usually found on buccal mucosa, labial mucosa of upper and lower lip, lateral tongue, and a variety of areas that may be bitten. To properly diagnose the ulcer, dentists should evaluate the history and clinical description in detail. If the lesion is allegedly accompanied by other infections, such as fungal, bacterial or viral infections, microbiological or serological tests will be required. One of the initial therapy given for fungal infection is nystatin which aimed to support the recovery and repair processes of epithelial tissue in traumatic ulcer case. Purpose: This case report is aimed to emphasize the importance of microbiological examination in suspected cases of ulcer accompanied with traumatic fungal infection. Case: A 12-year-old girl came to the clinic of Pediatric Dentistry, Faculty of Dentistry, University of Indonesia on June 9, 2011 accompanied with her mother. The patient who had a history of geographic tongue came with complaints of injury found in the middle of the tongue. The main diagnosis was ulcer accompanied with traumatic fungal infection based on the results of swab examination. Case management: This traumatic ulcer case was treated with Dental Health Education, oral prophylaxis, as well as prescribing and usage instructions of nystatin. The recovery and repair processes of mucosal epithelium of the tongue then occured after the use of nystatin. Conclusion: It can be concluded that microbiological examination is important to diagnose suspected cases of ulcer accompanied with traumatic fungal infection. The appropriate treatment such as nystatin can be given for traumatic fungal infection.Latar belakang: Ulkus traumatic merupakan bentuk umum dari ulserasi rongga mulut yang terjadi akibat trauma

  3. Indexing and Analysis of Fungal Phenotypes Using Morphology and Spectrometry

    DEFF Research Database (Denmark)

    Hansen, Michael Adsetts Edberg

    2005-01-01

    and identification of the fungi is considered difficult and laborious. Though visual expressions have been and still is used as phenotype markers in the classification and identification of fungal species, one of the most successful characters used has been the profile of the secondary metabolites. In order...... to evaluate the visual phenotypic characters, a method for visual clone identification of Penicillium commune { the most widespread and most frequently occurring spoilage fungus on cheese { was developed (Papers A, B and C). The method was based on images of fungal colonies acquired after growth on a standard...... extract highly complex and similar ESI-MS mass spectra for identifying fungal extracts in a reference library are being developed and tested (Paper E). Whereas mass spectrometry is one modality used in systematising the fungi, high pressure liquid chromatography combined with an UV diode array detector...

  4. Fungal phytotoxins with potential herbicidal activity: chemical and biological characterization.

    Science.gov (United States)

    Cimmino, Alessio; Masi, Marco; Evidente, Marco; Superchi, Stefano; Evidente, Antonio

    2015-12-19

    Covering: 2007 to 2015 Fungal phytotoxins are secondary metabolites playing an important role in the induction of disease symptoms interfering with host plant physiological processes. Although fungal pathogens represent a heavy constraint for agrarian production and for forest and environmental heritage, they can also represent an ecofriendly alternative to manage weeds. Indeed, the phytotoxins produced by weed pathogenic fungi are an efficient tool to design natural, safe bioherbicides. Their use could avoid that of synthetic pesticides causing resistance in the host plants and the long term impact of residues in agricultural products with a risk to human and animal health. The isolation and structural and biological characterization of phytotoxins produced by pathogenic fungi for weeds, including parasitic plants, are described. Structure activity relationships and mode of action studies for some phytotoxins are also reported to elucidate the herbicide potential of these promising fungal metabolites.

  5. Novel fungal disease in complex leaf-cutting ant societies

    DEFF Research Database (Denmark)

    Hughes, David Peter; Evans, Harry C.; Hywel-Jones, Nigel

    2009-01-01

    1. The leaf-cutting ants practise an advanced system of mycophagy where they grow a fungus as a food source. As a consequence of parasite threats to their crops, they have evolved a system of morphological, behavioural, and chemical defences, particularly against fungal pathogens (mycopathogens). 2....... Specific fungal diseases of the leaf-cutting ants themselves have not been described, possibly because broad spectrum anti-fungal defences against mycopathogens have reduced their susceptibility to entomopathogens. 3. Using morphological and molecular tools, the present study documents three rare infection...... events of Acromyrmex and Atta leaf-cutting ants by Ophiocordyceps fungi, agenus of entomopathogens that is normally highly specific in its host choice. 4. As leaf-cutting ants have been intensively studied, the absence of prior records of Ophiocordyceps suggests that these infections may be a novel event...

  6. Fungal degradation of pesticides - construction of microbial consortia for bioremediation

    DEFF Research Database (Denmark)

    Ellegaard-Jensen, Lea

    in groundwater contamination. New technologies are therefore needed for cleaning up contaminated soil and water resources. This PhD was part of the project entitled Microbial Remediation of Contaminated Soil and Water Resources (MIRESOWA) where the overall aim is to develop new technologies for bioremediation...... of pesticide contaminated soil and water. The objectives of this PhD were to investigate fungal degradation of pesticides and following to construct microbial consortia for bioremediation. In Manuscript I the fungal degradation of the phenylurea herbicide diuron was studied. Isolates of soil fungi of the genus...... slightly enhanced BAM distribution. From this work it is evident that the fungal-bacterial consortium is capable of enhancing BAM-degradation in unsaturated systems, and may therefore be a promising application for soil bioremediation. In Manuscript III two- and three-member consortia were constructed...

  7. Mortality related to neonatal and pediatric fungal infections

    Directory of Open Access Journals (Sweden)

    Paolo Manzoni

    2013-07-01

    Full Text Available Thanks to the recent advances in the treatment of neonatal fungal infections, the burden of mortality has been decreasing. However a widely accepted definition is yet to be found, since different thresholds of survival are used in the published trials, and therefore mortality is assumed as occurring 7, 20, 30, or 90 days after treatment, according to the different studies. Regardless of the uncertainty of the definitions, it is more important to know if the patient died with the fungal infection or because of the fungal infection. The new antifungal drugs currently available for neonatal patients were able to increase the survival rates: the attention should, therefore, be focused on the long-term seque­lae, which, on the contrary, still affect a big amount of patients. In particular, neurobehavioral and neurosensorial disorders become often evident with age.http://dx.doi.org/10.7175/rhc.v14i1S.857 

  8. In Vivo Roles of Fatty Acid Biosynthesis Enzymes in Biosynthesis of Biotin and α-Lipoic Acid in Corynebacterium glutamicum.

    Science.gov (United States)

    Ikeda, Masato; Nagashima, Takashi; Nakamura, Eri; Kato, Ryosuke; Ohshita, Masakazu; Hayashi, Mikiro; Takeno, Seiki

    2017-10-01

    For fatty acid biosynthesis, Corynebacterium glutamicum uses two type I fatty acid synthases (FAS-I), FasA and FasB, in addition to acetyl-coenzyme A (CoA) carboxylase (ACC) consisting of AccBC, AccD1, and AccE. The in vivo roles of the enzymes in supplying precursors for biotin and α-lipoic acid remain unclear. Here, we report genetic evidence demonstrating that the biosynthesis of these cofactors is linked to fatty acid biosynthesis through the FAS-I pathway. For this study, we used wild-type C. glutamicum and its derived biotin vitamer producer BFI-5, which was engineered to express Escherichia coli bioBF and Bacillus subtilis bioI Disruption of either fasA or fasB in strain BFI-5 led to decreased production of biotin vitamers, whereas its amplification contributed to increased production, with a larger impact of fasA in both cases. Double disruptions of fasA and fasB resulted in no biotin vitamer production. The acc genes showed a positive effect on production when amplified simultaneously. Augmented fatty acid biosynthesis was also reflected in pimelic acid production when carbon flow was blocked at the BioF reaction. These results indicate that carbon flow down the FAS-I pathway is destined for channeling into the biotin biosynthesis pathway, and that FasA in particular has a significant impact on precursor supply. In contrast, fasB disruption resulted in auxotrophy for lipoic acid or its precursor octanoic acid in both wild-type and BFI-5 strains. The phenotypes were fully complemented by plasmid-mediated expression of fasB but not fasA These results reveal that FasB plays a specific physiological role in lipoic acid biosynthesis in C. glutamicum IMPORTANCE For the de novo biosynthesis of fatty acids, C. glutamicum exceptionally uses a eukaryotic multifunctional type I fatty acid synthase (FAS-I) system comprising FasA and FasB, in contrast to most bacteria, such as E. coli and B. subtilis , which use an individual nonaggregating type II fatty acid synthase

  9. Prophylactic Saccharomyces boulardii versus nystatin for the prevention of fungal colonization and invasive fungal infection in premature infants.

    Science.gov (United States)

    Demirel, Gamze; Celik, Istemi Han; Erdeve, Omer; Saygan, Sibel; Dilmen, Ugur; Canpolat, Fuat Emre

    2013-10-01

    This study aims to compare the efficacy of orally administered Saccharomyces boulardii versus nystatin in prevention of fungal colonization and invasive fungal infections in very low birth weight infants. A prospective, randomized comparative study was conducted in preterm infants with a gestational age of ≤ 32 weeks and birth weight of ≤ 1,500 g. They were randomized into two groups, to receive S. boulardii or nystatin. Skin and stool cultures were performed for colonization and blood cultures for invasive infections, weekly. A total of 181 infants were enrolled (S. boulardii group, n = 91; nystatin group, n = 90). Fungal colonization of the skin (15.4 vs 18.9 %, p = 0.532) and the stool (32.2 vs 27 %, p = 0.441) were not different between the probiotic and nystatin groups. Two patients had Candida-positive blood culture in the nystatin group whereas none in the probiotic group. Feeding intolerance, clinical sepsis, and number of sepsis attacks were significantly lower in the probiotics group than in the nystatin group. Prophylactic S. boulardii supplementation is as effective as nystatin in reducing fungal colonization and invasive fungal infection, more effective in reducing the incidence of clinical sepsis and number of sepsis attacks and has favorable effect on feeding intolerance.

  10. Fungal farming in a non-social beetle.

    Directory of Open Access Journals (Sweden)

    Wataru Toki

    Full Text Available Culturing of microbes for food production, called cultivation mutualism, has been well-documented from eusocial and subsocial insects such as ants, termites and ambrosia beetles, but poorly described from solitary, non-social insects. Here we report a fungal farming in a non-social lizard beetle Doubledaya bucculenta (Coleoptera: Erotylidae: Languriinae, which entails development of a special female structure for fungal storage/inoculation, so-called mycangium, and also obligate dependence of the insect on the fungal associate. Adult females of D. bucculenta bore a hole on a recently-dead bamboo culm with their specialized mandibles, lay an egg into the internode cavity, and plug the hole with bamboo fibres. We found that the inner wall of the bamboo internode harboring a larva is always covered with a white fungal layer. A specific Saccharomycetes yeast, Wickerhamomyces anomalus ( = Pichia anomala, was consistently isolated from the inner wall of the bamboo internodes and also from the body surface of the larvae. Histological examination of the ovipositor of adult females revealed an exoskeletal pocket on the eighth abdominal segment. The putative mycangium contained yeast cells, and W. anomalus was repeatedly detected from the symbiotic organ. When first instar larvae were placed on culture media inoculated with W. anomalus, they grew and developed normally to adulthood. By contrast, first instar larvae placed on either sterile culture media or autoclaved strips of bamboo inner wall exhibited arrested growth at the second instar, and addition of W. anomalus to the media resumed growth and development of the larvae. These results strongly suggest a mutualistic nature of the D. bucculenta-W. anomalus association with morphological specialization and physiological dependence. Based on these results, we compare the fungal farming of D. bucculenta with those of social and subsocial insects, and discuss ecological factors relevant to the

  11. Fungal treated lignocellulosic biomass as ruminant feed ingredient: a review.

    Science.gov (United States)

    van Kuijk, S J A; Sonnenberg, A S M; Baars, J J P; Hendriks, W H; Cone, J W

    2015-01-01

    In ruminant nutrition, there is an increasing interest for ingredients that do not compete with human nutrition. Ruminants are specialists in digesting carbohydrates in plant cell walls; therefore lignocellulosic biomass has potential in ruminant nutrition. The presence of lignin in biomass, however, limits the effective utilization of cellulose and hemicellulose. Currently, most often chemical and/or physical treatments are used to degrade lignin. White rot fungi are selective lignin degraders and can be a potential alternative to current methods which involve potentially toxic chemicals and expensive equipment. This review provides an overview of research conducted to date on fungal pretreatment of lignocellulosic biomass for ruminant feeds. White rot fungi colonize lignocellulosic biomass, and during colonization produce enzymes, radicals and other small compounds to breakdown lignin. The mechanisms on how these fungi degrade lignin are not fully understood, but fungal strain, the origin of lignocellulose and culture conditions have a major effect on the process. Ceriporiopsis subvermispora and Pleurotus eryngii are the most effective fungi to improve the nutritional value of biomass for ruminant nutrition. However, conclusions on the effectiveness of fungal delignification are difficult to draw due to a lack of standardized culture conditions and information on fungal strains used. Methods of analysis between studies are not uniform for both chemical analysis and in vitro degradation measurements. In vivo studies are limited in number and mostly describing digestibility after mushroom production, when the fungus has degraded cellulose to derive energy for fruit body development. Optimization of fungal pretreatment is required to shorten the process of delignification and make it more selective for lignin. In this respect, future research should focus on optimization of culture conditions and gene expression to obtain a better understanding of the mechanisms

  12. Diverse honeydew-consuming fungal communities associated with scale insects.

    Directory of Open Access Journals (Sweden)

    Manpreet K Dhami

    Full Text Available Sooty mould fungi are ubiquitous, abundant consumers of insect-honeydew that have been little-studied. They form a complex of unrelated fungi that coexist and compete for honeydew, which is a chemically complex resource. In this study, we used scanning electron microscopy in combination with T-RFLP community profiling and ITS-based tag-pyrosequencing to extensively describe the sooty mould community associated with the honeydews of two ecologically important New Zealand coelostomidiid scale insects, Coelostomidia wairoensis and Ultracoelostoma brittini. We tested the influence of host plant on the community composition of associated sooty moulds, and undertook limited analyses to examine the influence of scale insect species and geographic location. We report here a previously unknown degree of fungal diversity present in this complex, with pyrosequencing detecting on average 243 operational taxonomic units across the different sooty mould samples. In contrast, T-RFLP detected only a total of 24 different "species" (unique peaks. Nevertheless, both techniques identified similar patterns of diversity suggesting that either method is appropriate for community profiling. The composition of the microbial community associated with individual scale insect species varied although the differences may in part reflect variation in host preference and site. Scanning electron microscopy visualised an intertwined mass of fungal hyphae and fruiting bodies in near-intact physical condition, but was unable to distinguish between the different fungal communities on a morphological level, highlighting the need for molecular research. The substantial diversity revealed for the first time by pyrosequencing and our inability to identify two-thirds of the diversity to further than the fungal division highlights the significant gap in our knowledge of these fungal groups. This study provides a first extensive look at the community diversity of the fungal community

  13. Transcriptomic response of the mycoparasitic fungus Trichoderma atroviride to the presence of a fungal prey.

    Science.gov (United States)

    Seidl, Verena; Song, Lifu; Lindquist, Erika; Gruber, Sabine; Koptchinskiy, Alexeji; Zeilinger, Susanne; Schmoll, Monika; Martínez, Pedro; Sun, Jibin; Grigoriev, Igor; Herrera-Estrella, Alfredo; Baker, Scott E; Kubicek, Christian P

    2009-11-30

    Combating the action of plant pathogenic microorganisms by mycoparasitic fungi has been announced as an attractive biological alternative to the use of chemical fungicides since two decades. The fungal genus Trichoderma includes a high number of taxa which are able to recognize, combat and finally besiege and kill their prey. Only fragments of the biochemical processes related to this ability have been uncovered so far, however. We analyzed genome-wide gene expression changes during the begin of physical contact between Trichoderma atroviride and two plant pathogens Botrytis cinerea and Rhizoctonia solani, and compared with gene expression patterns of mycelial and conidiating cultures, respectively. About 3000 ESTs, representing about 900 genes, were obtained from each of these three growth conditions. 66 genes, represented by 442 ESTs, were specifically and significantly overexpressed during onset of mycoparasitism, and the expression of a subset thereof was verified by expression analysis. The upregulated genes comprised 18 KOG groups, but were most abundant from the groups representing posttranslational processing, and amino acid metabolism, and included components of the stress response, reaction to nitrogen shortage, signal transduction and lipid catabolism. Metabolic network analysis confirmed the upregulation of the genes for amino acid biosynthesis and of those involved in the catabolism of lipids and aminosugars. The analysis of the genes overexpressed during the onset of mycoparasitism in T. atroviride has revealed that the fungus reacts to this condition with several previously undetected physiological reactions. These data enable a new and more comprehensive interpretation of the physiology of mycoparasitism, and will aid in the selection of traits for improvement of biocontrol strains by recombinant techniques.

  14. Transcriptomic response of the mycoparasitic fungus Trichoderma atroviride to the presence of a fungal prey

    Energy Technology Data Exchange (ETDEWEB)

    Seidl, Verena; Song, Lifu; Lindquist, Erika; Gruber, Sabine; Koptchinskiy, Alexeji; Zeilinger, Susanne; Schmoll, Monika; Martinez, Pedro; Sun, Jibin; Grigoriev, Igor; Herrera-Estrella, Alfredo; Baker, Scott E; Kubicek, Christian P.

    2010-07-23

    BACKGROUND: Combating the action of plant pathogenic microorganisms by mycoparasitic fungi has been announced as an attractive biological alternative to the use of chemical fungicides since two decades. The fungal genus Trichoderma includes a high number of taxa which are able to recognize, combat and finally besiege and kill their prey. Only fragments of the biochemical processes related to this ability have been uncovered so far, however. RESULTS: We analyzed genome-wide gene expression changes during the begin of physical contact between Trichoderma atroviride and two plant pathogens Botrytis cinerea and Rhizoctonia solani, and compared with gene expression patterns of mycelial and conidiating cultures, respectively. About 3000 ESTs, representing about 900 genes, were obtained from each of these three growth conditions. 66 genes, represented by 442 ESTs, were specifically and significantly overexpressed during onset of mycoparasitism, and the expression of a subset thereof was verified by expression analysis. The upregulated genes comprised 18 KOG groups, but were most abundant from the groups representing posttranslational processing, and amino acid metabolism, and included components of the stress response, reaction to nitrogen shortage, signal transduction and lipid catabolism. Metabolic network analysis confirmed the upregulation of the genes for amino acid biosynthesis and of those involved in the catabolism of lipids and aminosugars. CONCLUSION: The analysis of the genes overexpressed during the onset of mycoparasitism in T. atroviride has revealed that the fungus reacts to this condition with several previously undetected physiological reactions. These data enable a new and more comprehensive interpretation of the physiology of mycoparasitism, and will aid in the selection of traits for improvement of biocontrol strains by recombinant techniques.

  15. Transcriptomic response of the mycoparasitic fungus Trichoderma atroviride to the presence of a fungal prey

    Directory of Open Access Journals (Sweden)

    Herrera-Estrella Alfredo

    2009-11-01

    Full Text Available Abstract Background Combating the action of plant pathogenic microorganisms by mycoparasitic fungi has been announced as an attractive biological alternative to the use of chemical fungicides since two decades. The fungal genus Trichoderma includes a high number of taxa which are able to recognize, combat and finally besiege and kill their prey. Only fragments of the biochemical processes related to this ability have been uncovered so far, however. Results We analyzed genome-wide gene expression changes during the begin of physical contact between Trichoderma atroviride and two plant pathogens Botrytis cinerea and Rhizoctonia solani, and compared with gene expression patterns of mycelial and conidiating cultures, respectively. About 3000 ESTs, representing about 900 genes, were obtained from each of these three growth conditions. 66 genes, represented by 442 ESTs, were specifically and significantly overexpressed during onset of mycoparasitism, and the expression of a subset thereof was verified by expression analysis. The upregulated genes comprised 18 KOG groups, but were most abundant from the groups representing posttranslational processing, and amino acid metabolism, and included components of the stress response, reaction to nitrogen shortage, signal transduction and lipid catabolism. Metabolic network analysis confirmed the upregulation of the genes for amino acid biosynthesis and of those involved in the catabolism of lipids and aminosugars. Conclusion The analysis of the genes overexpressed during the onset of mycoparasitism in T. atroviride has revealed that the fungus reacts to this condition with several previously undetected physiological reactions. These data enable a new and more comprehensive interpretation of the physiology of mycoparasitism, and will aid in the selection of traits for improvement of biocontrol strains by recombinant techniques.

  16. A protein interaction map of the kalimantacin biosynthesis assembly line

    Directory of Open Access Journals (Sweden)

    Birgit Uytterhoeven

    2016-11-01

    Full Text Available The antimicrobial secondary metabolite kalimantacin is produced by a hybrid polyketide/ non-ribosomal peptide system in Pseudomonas fluorescens BCCM_ID9359. In this study, the kalimantacin biosynthesis gene cluster is analyzed by yeast two-hybrid analysis, creating a protein-protein interaction map of the entire assembly line. In total, 28 potential interactions were identified, of which 13 could be confirmed further. These interactions include the dimerization of ketosynthase domains, a link between assembly line modules 9 and 10, and a specific interaction between the trans-acting enoyl reductase BatK and the carrier proteins of modules 8 and 10. These interactions reveal fundamental insight into the biosynthesis of secondary metabolites.This study is the first to reveal interactions in a complete biosynthetic pathway. Similar future studies could build a strong basis for engineering strategies in such clusters.

  17. Biosynthesis and therapeutic properties of Lavandula essential oil constituents.

    Science.gov (United States)

    Woronuk, Grant; Demissie, Zerihun; Rheault, Mark; Mahmoud, Soheil

    2011-01-01

    Lavenders and their essential oils have been used in alternative medicine for several centuries. The volatile compounds that comprise lavender essential oils, including linalool and linalyl acetate, have demonstrative therapeutic properties, and the relative abundance of these metabolites is greatly influenced by the genetics and environment of the developing plants. With the rapid progress of molecular biology and the genomic sciences, our understanding of essential oil biosynthesis has greatly improved over the past few decades. At the same time, there is a recent surge of interest in the use of natural remedies, including lavender essential oils, in alternative medicine and aromatherapy. This article provides a review of recent developments related to the biosynthesis and medicinal properties of lavender essential oils. © Georg Thieme Verlag KG Stuttgart · New York.

  18. Enzymatic Reductive Dehalogenation Controls the Biosynthesis of Marine Bacterial Pyrroles.

    Science.gov (United States)

    El Gamal, Abrahim; Agarwal, Vinayak; Rahman, Imran; Moore, Bradley S

    2016-10-12

    Enzymes capable of performing dehalogenating reactions have attracted tremendous contemporary attention due to their potential application in the bioremediation of anthropogenic polyhalogenated persistent organic pollutants. Nature, in particular the marine environment, is also a prolific source of polyhalogenated organic natural products. The study of the biosynthesis of these natural products has furnished a diverse array of halogenation biocatalysts, but thus far no examples of dehalogenating enzymes have been reported from a secondary metabolic pathway. Here we show that the penultimate step in the biosynthesis of the highly brominated marine bacterial product pentabromopseudilin is catalyzed by an unusual debrominase Bmp8 that utilizes a redox thiol mechanism to remove the C-2 bromine atom of 2,3,4,5-tetrabromopyrrole to facilitate oxidative coupling to 2,4-dibromophenol. To the best of our knowledge, Bmp8 is first example of a dehalogenating enzyme from the established genetic and biochemical context of a natural product biosynthetic pathway.

  19. Cholesterol biosynthesis in polychlorinated biphenyl-treated rats

    International Nuclear Information System (INIS)

    Kling, D.; Gamble, W.

    1982-01-01

    After administration of polychlorinated biphenly (PCB) at 0.055 (w/w) of the diet to Wistar rats for 30 days, followed by intraperitioneal injection of tritiated water, [ 14 C]mevalonate, and [ 14 C]acetate, there was a decrease in cholesterol biosynthesis in rat liver. No significant change in cholesterol formation was observed when PCB was administered at 0.01% (w/w) of the diet. In vitro inhibition of cholesterol synthesis by rat liver microsomes was observed with PCB. Squalene 2,3-oxidocyclase activity of rat liver microsomes was not significantly altered. Desmosterol delta 24 reductase activity was inhibited only at relatively high concentrations of PCB. There was increased incorporation of radioactivity into squalene and lanosterol, in vitro, in the presence of PCB. The primary inhibition of cholesterol biosynthesis appears to be at the demethylation and rearrangement reactions between lanosterol and cholesterol in the biosynthetic pathway

  20. Engineering fatty acid biosynthesis in microalgae for sustainable biodiesel.

    Science.gov (United States)

    Blatti, Jillian L; Michaud, Jennifer; Burkart, Michael D

    2013-06-01

    Microalgae are a promising feedstock for biodiesel and other liquid fuels due to their fast growth rate, high lipid yields, and ability to grow in a broad range of environments. However, many microalgae achieve maximal lipid yields only under stress conditions hindering growth and providing compositions not ideal for biofuel applications. Metabolic engineering of algal fatty acid biosynthesis promises to create strains capable of economically producing fungible and sustainable biofuels. The algal fatty acid biosynthetic pathway has been deduced by homology to bacterial and plant systems, and much of our understanding is gleaned from basic studies in these systems. However, successful engineering of lipid metabolism in algae will necessitate a thorough characterization of the algal fatty acid synthase (FAS) including protein-protein interactions and regulation. This review describes recent efforts to engineer fatty acid biosynthesis toward optimizing microalgae as a biodiesel feedstock. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. [A systematic review of biosynthesis of poly (3-hydroxypropionate)].

    Science.gov (United States)

    Chang, Le; Zhan, Yuanlong; Liu, Changli

    2018-04-25

    Poly (3-hydroxypropionate) (P3HP), a new member of thermoplastic of family polyhydroxyalkanoates (PHAs), has excellent characteristics of biodegradability and biocompatibility. By now no reports can be found about wild-type bacteria that naturally synthesize P3HP, so the main way to produce P3HP is chemical and biological methods. Chemical method by adding high cost 3-HP monomers or their structural analogs as precursors, has the drawbacks of toxicity, low effectiveness and high cost. Biological method using engineered strain may utilize inexpensive and renewable carbon source to produce P3HP and has gradually become more and more popular. We systematically review here the biosynthesis of P3HP research progress. The advantages and disadvantages of biosynthesis pathways of glycerol pathway, malonyl-CoA pathway and β-alanine pathway were analyzed.

  2. Biosynthesis of Anthocyanins and Their Regulation in Colored Grapes

    Directory of Open Access Journals (Sweden)

    Guo-Liang Yan

    2010-12-01

    Full Text Available Anthocyanins, synthesized via the flavonoid pathway, are a class of crucial phenolic compounds which are fundamentally responsible for the red color of grapes and wines. As the most important natural colorants in grapes and their products, anthocyanins are also widely studied for their numerous beneficial effects on human health. In recent years, the biosynthetic pathway of anthocyanins in grapes has been thoroughly investigated. Their intracellular transportation and accumulation have also been further clarified. Additionally, the genetic mechanism regulating their biosynthesis and the phytohormone influences on them are better understood. Furthermore, due to their importance in the quality of wine grapes, the effects of the environmental factors and viticulture practices on anthocyanin accumulation are being investigated increasingly. The present paper summarizes both the basic information and the most recent advances in the study of the anthocyanin biosynthesis in red grapes, emphasizing their gene structure, the transcriptional factors and the diverse exterior regulation factors.

  3. Biosynthesis of anthocyanins and their regulation in colored grapes.

    Science.gov (United States)

    He, Fei; Mu, Lin; Yan, Guo-Liang; Liang, Na-Na; Pan, Qiu-Hong; Wang, Jun; Reeves, Malcolm J; Duan, Chang-Qing

    2010-12-09

    Anthocyanins, synthesized via the flavonoid pathway, are a class of crucial phenolic compounds which are fundamentally responsible for the red color of grapes and wines. As the most important natural colorants in grapes and their products, anthocyanins are also widely studied for their numerous beneficial effects on human health. In recent years, the biosynthetic pathway of anthocyanins in grapes has been thoroughly investigated. Their intracellular transportation and accumulation have also been further clarified. Additionally, the genetic mechanism regulating their biosynthesis and the phytohormone influences on them are better understood. Furthermore, due to their importance in the quality of wine grapes, the effects of the environmental factors and viticulture practices on anthocyanin accumulation are being investigated increasingly. The present paper summarizes both the basic information and the most recent advances in the study of the anthocyanin biosynthesis in red grapes, emphasizing their gene structure, the transcriptional factors and the diverse exterior regulation factors.

  4. Benchmarking of Processes for the Biosynthesis of Natural Products

    DEFF Research Database (Denmark)

    Seita, Catarina Sanches

    putida GS1. (R)-perillic acid is a monoterpenoic acid with antimicrobial properties. It has a strong inhibitory effect on bacteria and fungus, which makes it an attractive compound to be used as a preservative for instance in cosmetic industry, but on the other hand makes the biosynthesis a complicated....... These biological activities can be of interest for use in different sectors of chemical industry, in particular pharmaceutical industry where several drugs are derived or inspired by natural products structure. However, the large scale production of natural products is hindered by its relatively poor abundance...... of the process in comparison with other sweeteners. The main benefit of this early-stage evaluation is putting the biosynthesis of natural products into context in relation to demands of an industrially feasible chemical process. Moreover, it can give very meaningful insight into process development and provides...

  5. Biosynthesis and function of simple amides in Xenorhabdus doucetiae.

    Science.gov (United States)

    Bode, Edna; He, Yue; Vo, Tien Duy; Schultz, Roland; Kaiser, Marcel; Bode, Helge B

    2017-11-01

    Xenorhabdus doucetiae, the bacterial symbiont of the entomopathogenic nematode Steinernema diaprepesi produces several different fatty acid amides. Their biosynthesis has been studied using a combination of analysis of gene deletions and promoter exchanges in X. doucetiae and heterologous expression of candidate genes in E. coli. While a decarboxylase is required for the formation of all observed phenylethylamides and tryptamides, the acyltransferase XrdE encoded in the xenorhabdin biosynthesis gene cluster is responsible for the formation of short chain acyl amides. Additionally, new, long-chain and cytotoxic acyl amides were identified in X. doucetiae infected insects and when X. doucetiae was grown in Galleria Instant Broth (GIB). When the bioactivity of selected amides was tested, a quorum sensing modulating activity was observed for the short chain acyl amides against the two different quorum sensing systems from Chromobacterium and Janthinobacterium. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  6. Biosynthesis of collagen by fibroblasts kept in culture

    International Nuclear Information System (INIS)

    Machado-Santelli, G.M.

    1978-01-01

    The sinthesis of collagen is studied in fibroblasts of different origins with the purpose of obtaining an appropriate system for the study of its biosynthesis and processing. The percentage of collagen synthesis vary according to the fibroblast origin. Experiences are performed with fibroblasts kept in culture from: chicken - and guinea pig embryos, carragheenin - induced granulomas in adult guinea pig and from human skin. The collagen pattern synthesized after acetic acid - or saline extractions in the presence of inhibitors is also determined. This pattern is then assayed by poliacrilamide - 5% - SDS gel electrophoresis accompanied by fluorography. The importance of the cell culture system in the elucidation of collagen biosynthesis is pointed out. (M.A.) [pt

  7. Evolution of Fungal enzymes in the attine ant symbiosis

    DEFF Research Database (Denmark)

    de Fine Licht, Henrik Hjarvard; Schiøtt, Morten; Boomsma, Jacobus Jan

    The attine ant symbiosis is characterized by ancient but varying degrees of diffuse co-evolution between the ants and their fungal cultivars. Domesticated fungi became dependent on vertical transmission by queens and the ant colonies came to rely on their symbiotic fungus for food and thus...... as garden substrate, whereas the more basal genera use leaf litter, insect feces and insect carcasses. We hypothesized that enzyme activity of fungal symbionts has co-evolved with substrate use and we measured enzyme activities of fungus gardens in the field to test this, focusing particularly on plant...... essential for the symbiosis in general, but have contributed specifically to the evolution of the symbiosis....

  8. Release and characteristics of fungal fragments in various conditions

    Energy Technology Data Exchange (ETDEWEB)

    Mensah-Attipoe, Jacob [Department of Environmental Science, University of Eastern Finland, Yliopistonranta 1D, P. O. Box 1627, FI-70211 Kuopio (Finland); Saari, Sampo [Department of Physics, Tampere University of Technology, Korkeakoulunkatu 3, 33720 Tampere (Finland); Veijalainen, Anna-Maria; Pasanen, Pertti [Department of Environmental Science, University of Eastern Finland, Yliopistonranta 1D, P. O. Box 1627, FI-70211 Kuopio (Finland); Keskinen, Jorma [Department of Physics, Tampere University of Technology, Korkeakoulunkatu 3, 33720 Tampere (Finland); Leskinen, Jari T.T. [SIB Labs, University of Eastern Finland, Yliopistonranta 1E, P. O. Box 1627, FI-70211, Kuopio (Finland); Reponen, Tiina, E-mail: reponeta@ucmail.uc.edu [Department of Environmental Science, University of Eastern Finland, Yliopistonranta 1D, P. O. Box 1627, FI-70211 Kuopio (Finland); Department of Environmental Health, University of Cincinnati, P.O. Box 670056, Cincinnati, OH 45267-0056 (United States)

    2016-03-15

    Intact spores and submicrometer size fragments are released from moldy building materials during growth and sporulation. It is unclear whether all fragments originate from fungal growth or if small pieces of building materials are also aerosolized as a result of microbial decomposition. In addition, particles may be formed through nucleation from secondary metabolites of fungi, such as microbial volatile organic compounds (MVOCs). In this study, we used the elemental composition of particles to characterize the origin of submicrometer fragments released from materials contaminated by fungi. Particles from three fungal species (Aspergillus versicolor, Cladosporium cladosporioides and Penicillium brevicompactum), grown on agar, wood and gypsum board were aerosolized using the Fungal Spore Source Strength Tester (FSSST) at three air velocities (5, 16 and 27 m/s). Released spores (optical size, d{sub p} ≥ 0.8 μm) and fragments (d{sub p} ≤ 0.8 μm) were counted using direct-reading optical aerosol instruments. Particles were also collected on filters, and their morphology and elemental composition analyzed using scanning electron microscopes (SEMs) coupled with an Energy-Dispersive X-ray spectroscopy (EDX). Among the studied factors, air velocity resulted in the most consistent trends in the release of fungal particles. Total concentrations of both fragments and spores increased with an increase in air velocity for all species whereas fragment–spore (F/S) ratios decreased. EDX analysis showed common elements, such as C, O, Mg and Ca, for blank material samples and fungal growth. However, N and P were exclusive to the fungal growth, and therefore were used to differentiate biological fragments from non-biological ones. Our results indicated that majority of fragments contained N and P. Because we observed increased release of fragments with increased air velocities, nucleation of MVOCs was likely not a relevant process in the formation of fungal fragments. Based

  9. Bat white-nose syndrome: An emerging fungal pathogen?

    Science.gov (United States)

    Blehert, D.S.; Hicks, A.C.; Behr, M.; Meteyer, C.U.; Berlowski-Zier, B. M.; Buckles, E.L.; Coleman, J.T.H.; Darling, S.R.; Gargas, A.; Niver, R.; Okoniewski, J.C.; Rudd, R.J.; Stone, W.B.

    2009-01-01

    White-nose syndrome (WNS) is a condition associated with an unprecedented bat mortality event in the northeastern United States. Since the winter of 2006*2007, bat declines exceeding 75% have been observed at surveyed hibernacula. Affected bats often present with visually striking white fungal growth on their muzzles, ears, and/or wing membranes. Direct microscopy and culture analyses demonstrated that the skin of WNS-affected bats is colonized by a psychro-philic fungus that is phylogenetically related to Geomyces spp. but with a conidial morphology distinct from characterized members of this genus. This report characterizes the cutaneous fungal infection associated with WNS.

  10. The mycotoxin definition reconsidered towards fungal cyclic depsipeptides.

    Science.gov (United States)

    Taevernier, Lien; Wynendaele, Evelien; De Vreese, Leen; Burvenich, Christian; De Spiegeleer, Bart

    2016-04-02

    Currently, next to the major classes, cyclic depsipeptides beauvericin and enniatins are also positioned as mycotoxins. However, as there are hundreds more fungal cyclic depsipeptides already identified, should these not be considered as mycotoxins as well? The current status of the mycotoxin definition revealed a lack of consistency, leading to confusion about what compounds should be called mycotoxins. Because this is of pivotal importance in risk assessment prioritization, a clear and quantitatively expressed mycotoxin definition is proposed, based on data of widely accepted mycotoxins. Finally, this definition is applied to a set of fungal cyclic depsipeptides, revealing that some of these should indeed be considered as mycotoxins.

  11. Fungal and plant gene expression in arbuscular mycorrhizal symbiosis.

    Science.gov (United States)

    Balestrini, Raffaella; Lanfranco, Luisa

    2006-11-01

    Arbuscular mycorrhizas (AMs) are a unique example of symbiosis between two eukaryotes, soil fungi and plants. This association induces important physiological changes in each partner that lead to reciprocal benefits, mainly in nutrient supply. The symbiosis results from modifications in plant and fungal cell organization caused by specific changes in gene expression. Recently, much effort has gone into studying these gene expression patterns to identify a wider spectrum of genes involved. We aim in this review to describe AM symbiosis in terms of current knowledge on plant and fungal gene expression profiles.

  12. Fungal Agents as a Cause of Nasal Polyposis

    Directory of Open Access Journals (Sweden)

    Mohammad Nejadkazem

    2015-01-01

    Full Text Available Introduction: Sinonasal polyposis is the most common tumor of nasal cavity and sinuses. Its complications are but not limited to sinusitis, breathing difficulties, hyposmia, anosmia and bone erosion. Methods and materials: A total of 98 patients with sinonasal polyposis were examined for suspicious causative fungal agent. Results: Direct microscopy and culture confirmed fungal agent in 8 patients (8.1% from which 3 cases had Alternaria spp, 1 patient Aspergillus spp, 1 patient Bipolaris spp, and 3 patients yeast. Conclusion: Fungi may be considered as a potential cause of sinonasal polyposis.   Keywords: Sinonasal Polyposis, Rhinosinusitis, Fungi

  13. Successful treatment of Beauveria bassiana fungal keratitis with topical voriconazole.

    Science.gov (United States)

    Ogawa, Akiko; Matsumoto, Yukihiro; Yaguchi, Takashi; Shimmura, Shigeto; Tsubota, Kazuo

    2016-04-01

    We describe a 66-year-old woman who suffered from fungal keratitis after corneal transplantation. The causative organism was identified as Beauveria bassiana on the basis of morphological characteristics and the sequence of the internal transcribed spacer region of the ribosomal RNA gene. The patient was successfully treated with topical voriconazole (VRCZ) use only. We, hereby, present the first report of a case with B. bassiana fungal keratitis that responded to topical antifungal VRCZ treatment. Copyright © 2015 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  14. The fungal consortium of Andromeda polifolia in bog habitats

    Directory of Open Access Journals (Sweden)

    N.V. Filippova

    2015-09-01

    Full Text Available (1 Andromeda polifolia (bog rosemary is a common plant species in northern circumboreal peatlands. While not a major peat-forming species in most peatlands, it is characterised by a substantial woody below-ground biomass component that contributes directly to the accumulation of organic matter below the moss surface, as well as sclerophyllous leaf litter that contributes to the accumulation of organic matter above the moss surface. Rather little is known about the fungal communities associated with this plant species. Hence, we investigated the fungal consortium of A. polifolia in three distinct vegetation communities of ombrotrophic bogs near Khanty-Mansiysk, West Siberia, Russia, in 2012 and 2013. These vegetation communities were forested bog (Tr = treed, Sphagnum-dominated lawn (Ln, and Eriophorum-Sphagnum-dominated hummock (Er. (2 In total, 37 fungal taxa, belonging to five classes and 16 families, were identified and described morphologically. Seven fungal species were previously known from Andromeda as host. Others are reported for the first time, thus considerably expanding the fungal consortium of this dwarf shrub. Most taxa were saprobic on fallen leaves of A. polifolia found amongst Sphagnum in the bog. Two taxa were parasitic on living plant tissues and one taxon was saprobic on dead twigs. Three taxa, recorded only on A. polifolia leaves and on no other plant species or materials, may be host-specific to this dwarf shrub. (3 A quantitative analysis of the frequency of occurrence of all taxa showed that one taxon (Coccomyces duplicarioides was very abundant, 64 % of the taxa occurred frequently, and 32 % of the taxa occurred infrequently. The mean Shannon diversity index of the community was 2.4. (4 There were no statistical differences in the fungal community composition of A. polifolia in the three vegetation communities investigated in this study. Redundancy analysis suggested that some fungal taxa were positively, and others

  15. Determination of fungal spore release from wet building materials

    DEFF Research Database (Denmark)

    Kildesø, J.; Wurtz, H.; Nielsen, Kristian Fog

    2003-01-01

    The release and transport of fungal spores from water-damaged building materials is a key factor for understanding the exposure to particles of fungal origin as a possible cause of adverse health effects associated to growth of fungi indoors. In this study, the release of spores from nine species...... of typical indoor fungi has been measured under controlled conditions. The fungi were cultivated for a period of 4-6 weeks on sterilized wet wallpapered gypsum boards at a relative humidity (RH) of approximately 97%. A specially designed small chamber (P-FLEC) was placed on the gypsum board. The release...

  16. Fungal melanin: what do we know about structure?

    Directory of Open Access Journals (Sweden)

    Joshua D Nosanchuk

    2015-12-01

    Full Text Available The production of melanin significantly enhances the virulence of many important human pathogenic fungi. Despite fungal melanin’s importance in human disease, as well as melanin’s contribution to the ability of fungi to survive in diverse hostile environments, the structure of melanin remains unsolved. Nevertheless, ongoing research efforts have progressively revealed several notable structural characteristics of this enigmatic pigment, which will be the focus of this review. These compositional and organizational insights could further our ability to develop novel therapeutic approaches to combat fungal disease and enhance our understanding of how melanin is inserted into the cell wall.

  17. The state of proteome profiling in the fungal genus Aspergillus.

    Science.gov (United States)

    Kim, Yonghyun; Nandakumar, M P; Marten, Mark R

    2008-03-01

    Aspergilli are an important genus of filamentous fungi that contribute to a multibillion dollar industry. Since many fungal genome sequencing were recently completed, it would be advantageous to profile their proteome to better understand the fungal cell factory. Here, we review proteomic data generated for the Aspergilli in recent years. Thus far, a combined total of 28 cell surface, 102 secreted and 139 intracellular proteins have been identified based on 10 different studies on Aspergillus proteomics. A summary proteome map highlighting identified proteins in major metabolic pathway is presented.

  18. Beringian paleoecology inferred from permafrost-preserved fungal DNA

    DEFF Research Database (Denmark)

    Lydolph, Magnus C; Jacobsen, Jonas; Arctander, Peter

    2005-01-01

    of eukaryotic DNA sequences that were 510 bp long, including sequences of various fungi, plants, and invertebrates, could be obtained reproducibly from samples that were up to 300,000 to 400,000 years old. The sequences revealed that ancient fungal communities included a diversity of cold-adapted yeasts, dark......-pigmented fungi, plant-parasitic fungi, and lichen mycobionts. DNA traces of tree-associated macrofungi in a modern tundra sample indicated that there was a shift in fungal diversity following the last ice age and supported recent results showing that there was a severe change in the plant composition...

  19. Isotopologue fractionation during N(2)O production by fungal denitrification.

    Science.gov (United States)

    Sutka, Robin L; Adams, Gerard C; Ostrom, Nathaniel E; Ostrom, Peggy H

    2008-12-01

    Identifying the importance of fungi to nitrous oxide (N2O) production requires a non-intrusive method for differentiating between fungal and bacterial N2O production such as natural abundance stable isotopes. We compare the isotopologue composition of N2O produced during nitrite reduction by the fungal denitrifiers Fusarium oxysporum and Cylindrocarpon tonkinense with published data for N2O production during bacterial nitrification and denitrification. The fractionation factors for bulk nitrogen isotope values for fungal denitrification were in the range -74.7 to -6.6 per thousand. There was an inverse relationship between the absolute value of the fractionation factors and the reaction rate constant. We interpret this in terms of variation in the relative importance of the rate constants for diffusion and enzymatic reduction in controlling the net isotope effect for N2O production during fungal denitrification. Over the course of nitrite reduction, the delta(18)O values for N2O remained constant and did not exhibit a relationship with the concentration characteristic of an isotope effect. This probably reflects isotopic exchange with water. Similar to the delta(18)O data, the site preference (SP; the difference in delta(15)N between the central and outer N atoms in N2O) was unrelated to concentration during nitrite reduction and, therefore, has the potential to act as a conservative tracer of production from fungal denitrification. The SP values of N2O produced by F. oxysporum and C. tonkinense were 37.1 +/- 2.5 per thousand and 36.9 +/- 2.8 per thousand, respectively. These SP values are similar to those obtained in pure culture studies of bacterial nitrification but quite distinct from SP values for bacterial denitrification. The large magnitude of the bulk nitrogen isotope fractionation and the delta(18)O values associated with fungal denitrification are distinct from bacterial production pathways; thus multiple isotopologue data holds much promise for

  20. Models of Caenorhabditis elegans infection by bacterial and fungal pathogens.

    Science.gov (United States)

    Powell, Jennifer R; Ausubel, Frederick M

    2008-01-01

    The nematode Caenorhabditis elegans is a simple model host for studying the relationship between the animal innate immune system and a variety of bacterial and fungal pathogens. Extensive genetic and molecular tools are available in C. elegans, facilitating an in-depth analysis of host defense factors and pathogen virulence factors. Many of these factors are conserved in insects and mammals, indicating the relevance of the nematode model to the vertebrate innate immune response. Here, we describe pathogen assays for a selection of the most commonly studied bacterial and fungal pathogens using the C. elegans model system.