WorldWideScience

Sample records for subtilis var niger

  1. Foam separation of Pseudomonas fluorescens and Bacillus subtilis var. niger.

    Science.gov (United States)

    Grieves, R B; Wang, S L

    1967-01-01

    An experimental investigation established the effect of the presence of inorganic salts on the foam separation of Pseudomonas fluorescens and of Bacillus subtilis var. niger (B. globigii) from aqueous suspension by use of a cationic surfactant. For P. fluorescens, 5.0 mueq/ml of NaCl, KCl, Na(2)SO(4), K(2)SO(4), CaCl(2), CaSO(4), MgCl(2), or MgSO(4) produced increases in the cell concentration in the residual suspension (not carried into the foam) from 2.9 x 10(5) up to 1.6 x 10(6) to 2.8 x 10(7) cells per milliliter (initial suspensions contain from 3.3 x 10(7) to 4.8 x 10(7) cells per milliliter). The exceptional influence of magnesium was overcome by bringing the cells into contact first with the surfactant and then the salt. For B. subtilis, the presence of 5.0 mueq/ml of any of the eight salts increased the residual cell concentration by one order of magnitude from 1.2 x 10(4) to about 4.0 x 10(5) cells per milliliter. This occurred regardless of the sequence of contact as long as the surfactant contact period was sufficient. The presence of salts increased collapsed foam volumes with P. fluorescens and decreased collapsed foam volumes with B. subtilis.

  2. The structure of teichoic acid from Bacillus subtilis var. niger WM as determined by 13C nuclear-magnetic-resonance spectroscopy

    International Nuclear Information System (INIS)

    De Boer, W.R.; Kruyssen, F.J.; Wouters, J.T.M.; Kruk, C.

    1976-01-01

    The walls of Bacillus subtilis var. niger WM, grown in a Mg 2+ -limited chemostat culture (carbon source glucose, dilution rate = 0.2 h -1 , 37 0 C, pH 7) contained 45% (w/w) teichoic acid, a polymer composed of glycerol, phosphate and glucose in the molar ratio 1.00 : 1.00 : 0.88. Alkaline hydrolysis of this teichoic acid yielded 1-O-β-glucosylglycerol phosphate (together with small amounts of glycerol phosphate), and 13 C nuclear magnetic resonance spectra of this hydrolysis product, and its derivative after alkaline phosphatase treatment, confirmed that the monomeric unit was 1-O-β-glucosylglycerol-3-phosphate. Assignment of the resonances in the spectrum of undegraded teichoic acid revealed that the polymer was a poly[(2,3)glycerol phosphate], glucosidically substituted on C-1 of glycerol with β-glucose. (orig.) [de

  3. Ochratoxin A production by strains of Aspergillus niger var. niger.

    Science.gov (United States)

    Abarca, M L; Bragulat, M R; Castellá, G; Cabañes, F J

    1994-01-01

    In a survey of the occurrence of ochratoxin A (OA)-positive strains isolated from feedstuffs, two of the 19 isolates of Aspergillus niger var. niger that were studied produced OA in 2% yeast extract-15% sucrose broth and in corn cultures. This is the first report of production of OA by this species. PMID:8074536

  4. Esterilização por óxido de etileno: I. Influência do meio de esporulação na resistência dos esporos de Bacillus subtilis var. niger

    Directory of Open Access Journals (Sweden)

    Terezinha de Jesus A. Pinto

    1992-12-01

    Full Text Available Tendo por meta a padronização das variáveis influenciando a resistência de esporos empregados no controle do processo esterilizante por óxido de etileno, foram obtidos esporos de Bacillus subtilis var. niger, em meio sólido e líquido sintético de esporulação. Tais esporos, após padronização quantitativa dos 12 lotes obtidos, foram submetidos a exposições subletais como bioindicadores, tendo o papel como suporte. Construiu-se, então, a curva de letalidade característica de cada lote. A análise estatística empregada não evidenciou diferenças entre resistência dos 10 lotes obtidos em meio sólido e os 2 em meio líquido sintético, ressaltando-se a vantagem quanto ao rendimento que caracterizou a primeira metodologia.

  5. Esterilização por óxido de etileno: I. Influência do meio de esporulação na resistência dos esporos de Bacillus subtilis var. niger

    Directory of Open Access Journals (Sweden)

    Pinto Terezinha de Jesus A.

    1992-01-01

    Full Text Available Tendo por meta a padronização das variáveis influenciando a resistência de esporos empregados no controle do processo esterilizante por óxido de etileno, foram obtidos esporos de Bacillus subtilis var. niger, em meio sólido e líquido sintético de esporulação. Tais esporos, após padronização quantitativa dos 12 lotes obtidos, foram submetidos a exposições subletais como bioindicadores, tendo o papel como suporte. Construiu-se, então, a curva de letalidade característica de cada lote. A análise estatística empregada não evidenciou diferenças entre resistência dos 10 lotes obtidos em meio sólido e os 2 em meio líquido sintético, ressaltando-se a vantagem quanto ao rendimento que caracterizou a primeira metodologia.

  6. 40 CFR 180.1243 - Bacillus subtilis var. amyloliquefaciens strain FZB24; exemption from the requirement of a...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus subtilis var... EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1243 Bacillus subtilis... the requirement of a tolerance for residues of the Bacillus subtilis var. amyloliquefaciens strain...

  7. Toxicological assessment of nattokinase derived from Bacillus subtilis var. natto.

    Science.gov (United States)

    Lampe, Bradley J; English, J Caroline

    2016-02-01

    Subtilisin NAT, commonly known as "nattokinase," is a fibrinolytic enzyme produced by the bacterial strain B. subtilis var. natto, which plays a central role in the fermentation of soybeans into the popular Japanese food natto. Recent studies have reported on the potential anticoagulatory and antihypertensive effects of nattokinase administration in humans, with no indication of adverse effects. To evaluate the safety of nattokinase in a more comprehensive manner, several GLP-compliant studies in rodents and human volunteers have been conducted with the enzyme product, NSK-SD (Japan Bio Science Laboratory Co., Ltd., Japan). Nattokinase was non-mutagenic and non-clastogenic in vitro, and no adverse effects were observed in 28-day and 90-day subchronic toxicity studies conducted in Sprague-Dawley rats at doses up to 167 mg/kg-day and 1000 mg/kg-day, respectively. Mice inoculated with 7.55 × 10(8) CFU of the enzyme-producing bacterial strain showed no signs of toxicity or residual tissue concentrations of viable bacteria. Additionally consumption of 10 mg/kg-day nattokinase for 4 weeks was well tolerated in healthy human volunteers. These findings suggest that the oral consumption of nattokinase is of low toxicological concern. The 90-day oral subchronic NOAEL for nattokinase in male and female Sprague-Dawley rats is 1000 mg/kg-day, the highest dose tested. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Niger

    DEFF Research Database (Denmark)

    Hahonou, Eric Komlavi

    2015-01-01

    The chapter provides knowledge about the role of non-state actors in security provision in Niger. It argues that it is of upmost importance to dig into the causes of ongoing armed conflicts and volatile situations. It points out the long-term decline of public service provision (including the role...

  9. α--AMYLASES OF Aspergillus flavus var. oryzae AND Bacillus subtilis: THE SUBSTRATE SPECIFICITY AND RESISTANCE TO A NUMBER OF CHEMICALLY ACTIVE SUBSTANCES

    Directory of Open Access Journals (Sweden)

    K. V. Avdiyuk

    2013-06-01

    Full Text Available The ability of Aspergillus flavus var. oryzae 80428 and Bacillus subtilis 147 α-amylases to split different carbohydrate-containing substrates, such as maltose, sucrose, trehalose, dextrin, α- and β-cyclodextrin, amylose, amylopectin, glycogen, pullulan, soluble starch, insoluble starch, corn starch, wheat starch, dextran 500 has been studied. It was shown that investigated enzymes differ by substrate specificity. α-Amylase of A. flavus var. oryzae 80428 rapidly hydrolysed soluble potato and wheat starch, while the α-amylase of B. subtilis 147 — only wheat starch. Both enzymes don’t cleave maltose, α-cyclodextrin and dextran 500. A. flavus var. oryzae 80428 α-amylase display very small ability to hydrolyze pullulan, while α-amylase of B. subtilis 147 it does not act in general. The lowest values of Michaelis constant for both enzymes at splitting of glycogen have been obtained, indicating that enzymes have the greatest affinity to this substrate. The studies of influence of chemically active substances on activity of A. flavus var. oryzae 80428 and B. subtilis 147 ?-amylases show there are resistant to urea, deoxycholic acid, Tween-80, Triton X-100 and hydrogen peroxide. It’s indicate the enzymes tested may be competitive in compare with earlier described in literature enzymes. The obtained results give a possibility to propose in future usage these enzymes in different fields of industry, foremost in detergent industry.

  10. Antilithiasic and Hypolipidaemic Effects of Raphanus sativus L. var. niger on Mice Fed with a Lithogenic Diet

    Science.gov (United States)

    Castro-Torres, Ibrahim Guillermo; Naranjo-Rodríguez, Elia Brosla; Domínguez-Ortíz, Miguel Ángel; Gallegos-Estudillo, Janeth; Saavedra-Vélez, Margarita Virginia

    2012-01-01

    In Mexico, Raphanus sativus L. var. niger (black radish) has uses for the treatment of gallstones and for decreasing lipids serum levels. We evaluate the effect of juice squeezed from black radish root in cholesterol gallstones and serum lipids of mice. The toxicity of juice was analyzed according to the OECD guidelines. We used female C57BL/6 mice fed with a lithogenic diet. We performed histopathological studies of gallbladder and liver, and measured concentrations of cholesterol, HDL cholesterol and triglycerides. The juice can be considered bioactive and non-toxic; the lithogenic diet significantly induced cholesterol gallstones; increased cholesterol and triglycerides levels, and decreased HDL levels; gallbladder wall thickness increased markedly, showing epithelial hyperplasia and increased liver weight. After treatment with juice for 6 days, cholesterol gallstones were eradicated significantly in the gallbladder of mice; cholesterol and triglycerides levels decreased too, and there was also an increase in levels of HDL (P < 0.05). Gallbladder tissue continued to show epithelial hyperplasia and granulocyte infiltration; liver tissue showed vacuolar degeneration. The juice of black radish root has properties for treatment of cholesterol gallstones and for decreasing serum lipids levels; therefore, we confirm in a preclinical study the utility that people give it in traditional medicine. PMID:23093836

  11. Constitutive expression of fluorescent protein by Aspergillus var. niger and Aspergillus carbonarius to monitor fungal colonization in maize plants

    Science.gov (United States)

    Aspergillus niger and A. carbonarius are two species in the Aspergillus section Nigri (black-spored aspergilli) frequently associated with peanut (Arachis hypogea), maize (Zea mays), and other plants as pathogens. These infections are symptomless and as such are major concerns since some black aspe...

  12. Immunostimulatory Activity of Opuntia ficus-indica var. Saboten Cladodes Fermented by Lactobacillus plantarum and Bacillus subtilis in RAW 264.7 Macrophages.

    Science.gov (United States)

    Hwang, Joon-Ho; Lim, Sang-Bin

    2017-02-01

    To increase the functionality of Opuntia ficus-indica var. saboten cladodes, it was fermented by Lactobacillus plantarum and Bacillus subtilis. Eighty percent methanol extracts were investigated for their effects on nitric oxide (NO) production, cytokine secretion, nuclear factor-κB (NF-κB) activity, and mitogen-activated protein kinase (MAPK) phosphorylation in RAW 264.7 cells. Methanol extracts of L. plantarum culture medium (LPCME) and B. subtilis culture medium (BSCME) did not affect lipopolysaccharide (LPS)-induced NO production but, at 500 μg/mL, increased interferon (IFN)-γ-induced NO production by 55.2 and 66.5 μM, respectively, in RAW 264.7 cells. In RAW 264.7 cells not treated with LPS and IFN-γ, LPCME did not affect NO production, but BSCME increased NO production significantly in a dose-dependent manner. In addition, BSCME induced the expression of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in RAW 264.7 cells in a dose-dependent manner. BSCME at 500 μg/mL increased TNF-α and IL-1β mRNA levels by 83.8% and 82.2%, respectively. BSCME increased NF-κB-dependent luciferase activity in a dose-dependent manner; 500 μg/mL BSCME increased activity 9.1-fold compared with the control. BSCME induced the phosphorylation of p38, c-JUN NH 2 -terminal protein kinase (JNK), and extracellular signal-regulated kinase (ERK) in a dose-dependent manner, but did not affect total ERK levels. In conclusion, BSCME exerted immunostimulatory effects, which were mediated by MAPK phosphorylation and NF-κB activation, resulting in increased TNF-α and IL-1β gene expression in RAW 264.7 macrophages. Therefore, BSCM shows promise for use as an immunostimulatory therapeutic.

  13. Constitutive expression of fluorescent protein by Aspergillus var. niger and Aspergillus carbonarius to monitor fungal colonization in maize plants.

    Science.gov (United States)

    Palencia, Edwin Rene; Glenn, Anthony Elbie; Hinton, Dorothy Mae; Bacon, Charles Wilson

    2013-09-01

    Aspergillus niger and Aspergillus carbonarius are two species in the Aspergillus section Nigri (black-spored aspergilli) frequently associated with peanut (Arachis hypogea), maize (Zea mays), and other plants as pathogens. These infections are symptomless and as such are major concerns since some black aspergilli produce important mycotoxins, ochratoxins A, and the fumonisins. To facilitate the study of the black aspergilli-maize interactions with maize during the early stages of infections, we developed a method that used the enhanced yellow fluorescent protein (eYFP) and the monomeric red fluorescent protein (mRFP1) to transform A. niger and A. carbonarius, respectively. The results were constitutive expressions of the fluorescent genes that were stable in the cytoplasms of hyphae and conidia under natural environmental conditions. The hyphal in planta distribution in 21-day-old seedlings of maize were similar wild type and transformants of A. niger and A. carbonarius. The in planta studies indicated that both wild type and transformants internally colonized leaf, stem and root tissues of maize seedlings, without any visible disease symptoms. Yellow and red fluorescent strains were capable of invading epidermal cells of maize roots intercellularly within the first 3 days after inoculation, but intracellular hyphal growth was more evident after 7 days of inoculation. We also tested the capacity of fluorescent transformants to produce ochratoxin A and the results with A. carbonarius showed that this transgenic strain produced similar concentrations of this secondary metabolite. This is the first report on the in planta expression of fluorescent proteins that should be useful to study the internal plant colonization patterns of two ochratoxigenic species in the Aspergillus section Nigri. © 2013.

  14. Fast Neutron Radiation Effects on Bacillus Subtili

    International Nuclear Information System (INIS)

    Chen Xiaoming; Zhang Jianguo; Chu Shijin; Ren Zhenglong; Zheng Chun; Yang Chengde; Tan Bisheng

    2009-01-01

    To examine the sterilizing effect and mechanism of neutron radiation, Bacillus subtilis var. niger. strain (ATCC 9372) spores were irradiated with the fast neutron from the Chinese fast burst reactor II(CFBR-II). The plate-count results indicated that the D 10 value was 384.6 Gy with a neutron radiation dose rate of 7.4 Gy/min. The rudimental catalase activity of the spores declined obviously with the increase in the radiation dose. Meanwhile, under the scanning electron microscope, no visible influence of the neutron radiation on the spore configuration was detected even if the dose was increased to 4 kGy. The content and distribution of DNA double-strand breaks induced by neutron radiation at different doses were measured and quantified by pulsed-field gel electrophoresis (PFGE). Further analysis of the DNA release percentage (PR), the DNA breakage level (L), and the average molecular weight, indicated that DNA fragments were obviously distributed around the 5 kb regions at different radiation doses, which suggests that some points in the DNA molecule were sensitive to neutron radiation. Both PR and L varied regularly to some extent with the increase in radiation dose. Thus neutron radiation has a high sterilization power, and can induce falling enzyme activity and DNA breakage in Bacillus subtilis spores

  15. Stabilizing Niger

    DEFF Research Database (Denmark)

    Hahonou, Eric Komlavi

    international intervention in Niger. Their main objective is to secure their own strategic, economic and political interests by strengthening the Nigerien authorities through direct intervention and capacity building activities. For western states reinforcing state security institutions and stabilizing elite...

  16. COMPLEXES OF BISCITRATOGERMANATES AND BISCITRATOSTANATES WITH METALS ARE MODIFIERS OF ACTIVITY OF Bacillus thuringiensis var. іsraelensis PEPTIDASES AND α-Penicillium canescens, Cladosporium cladosporioides AND Aspergillus niger GALACTOIDASES

    Directory of Open Access Journals (Sweden)

    L. D. Varbanets

    2016-06-01

    Full Text Available The aim of the research was to study the effect of a number of coordination compounds of stanum and germanium (compounds 1‒8 as modifiers of activity of peptidases and α-galactosidases. The coordination compounds with the same type structure of were investigated as enzymes effectors. Two types of complexes: 1 [M(H2O6][Ge(НCitr2]4H2O (M = Mg(1, Mn(2, Co(3, Ni(4, Zn(5, containing biscitrate-stanate anion ([Ge(НCitr2]2-, and 2 [M(H2O6][Sn(НCitr2]4H2O (M = Mg(6, Co(7, Ni(8, containing biscitratostanate anion and various hexaaquacations ([M(H2O6]2+, М= Mg, Mn, Co, Ni, Zn were studied. It is shown that the compound 6 which is a biscitratostanate complex containing magnesium ions as metal, can be used for stimulation on 20‒25% of collagenase activity of B. thuringiensis var. israelensis IMV B-7465 peptidase 1 and peptidase 2. Compound 1 (biscitrate-stanate complex containing magnesium ions as metal and 7 (biscitratostanate complex containing cobalt ions as metal and compound 6 in a concentration of 0.001% are able to increase elastolytic activity of peptidase 1 on 55‒58%. However compound 7 has shown the greatest activating effect. It increased the elastolytic activity of peptidase 2 on 100‒140% (for both tested concentrations. This indicates that the compound 7 can further be used as of peptidase 2 elastolytic activity effector. In the study of effect of the considered coordination compounds on the activity of α-galactosidase of Penicillium canescens, Cladosporium cladosporioides and Aspergillus niger was found that when using a number of complexes (1‒2 and 4‒8, there is a slight increase on 12‒20% of enzyme activity of P. canescens, and the maximum effect (~20%, concentration 0.01% was provided by complex 6.

  17. Decontamination of Bacillus subtilis Spores in a Sealed Package Using a Non-thermal Plasma System

    Science.gov (United States)

    Keener, Kevin M.; Jensen, J. L.; Valdramidis, V. P.; Byrne, E.; Connolly, J.; Mosnier, J. P.; Cullen, P. J.

    The safety of packaged food and medical devices is a major concern to consumers and government officials. Recent inventions (PK-1 and PK-2) based on the principles of non-thermal, atmospheric plasma has shown significant reduction in bacterial contamination inside a sealed package. The objective of this study was to evaluate the PK-1 and PK-2 systems in the reduction of Bacillus subtilis spores using packages containing air or modified atmosphere (MA) gas (65% O2/30% CO2/5% N2). The experimental design consisted of the following parameters: (1) two voltage conditions: 13.5 kV with 1.0 cm electrode gap (PK-1) and 80 kV with 4.5 cm electrode gap (PK-2), (2) two treatment conditions: inside and outside the field of ionization, (3) PK-1 and PK-2 optimized treatment times: 300 and 120 s, respectively, and (4) two package gas types: air and modified atmosphere (MA) gas (65% O2/30% CO2/5% N2). Measurements included: (1) bacterial reductions of Bacillus subtilis var. niger (B. atrophaeus), (2) ozone, nitrous oxides (NOx), and carbon monoxide concentrations, and (3) relative humidity. Bacillus subtilis (1.7 × 106/strip) were loaded into sterile uncovered petri dishes and treated with ionization generated in packages using air or MA gas blend. Samples were treated for 300 s (PK-1) or 120 s (PK-2) and stored at room ­temperature for 24 h. Results documented relative humidity (RH) ranged from 20% to 30%. After 300 s of PK-1 treatment (13.5 kV/44 W/1.0 cm gap), ozone concentrations were 6,000 ppm (air) and 7,500 ppm (MA). After 120 s of PK-2 treatment (80 kV/150 W/4.5 cm), ozone concentrations were 7,500 ppm (air) and 12,000 ppm (MA). Ozone and NOx concentrations were non-detect (ND) after 24 h. PK-1 carbon monoxide levels were package ionization process.

  18. Host organisms: Bacillus subtilis

    NARCIS (Netherlands)

    Hohman, Hans-Peter; van Dijl, Jan; Krishnappa, Laxmi; Pragai, Zoltan

    2016-01-01

    Bacillus subtilis and its close Bacillus relatives are important bacterial platforms for industrial production of enzymes and fine chemicals such as vitamin B2 and nucleotides. B. subtilis is an attractive bacterial organism for industrial use mainly because of its straightforward genetic

  19. Women of Niger Delta

    African Journals Online (AJOL)

    Religion Dept

    The Indispensability of Women in Conflict Resolution in the Niger Delta ... The situation leads to a shift in gender roles with a dramatic increase in the number of women .... organization is to work in partnership with the Nigerian Government and the .... that “women are the impartial arbitrators in family or clan disputes or.

  20. western niger delta, nigeria

    African Journals Online (AJOL)

    HP

    2015-07-21

    Jul 21, 2015 ... River Niger catchment being along the corridors of mangrove and forest region might be responsible for the persistence in the occurrence of mangrove and rain forest pollen Zonocostites ramonae and Retitricolporites irregularis, Canthium spp. throughout the stratigraphic column of the well. REFERENCES.

  1. IDRC in Niger

    International Development Research Centre (IDRC) Digital Library (Canada)

    IDRC has supported research in. Niger since 1974. This support has been sporadic in the absence of democratic stability in the country. It has nonetheless enabled researchers to develop ways to counter deforestation and test varieties of cereal and legume crops that can resist drought conditions. Research on the effects of ...

  2. The Niger Delta

    African Journals Online (AJOL)

    AJL

    2009-05-26

    May 26, 2009 ... Available online at http://www.academicjournals.org/AJEST. ISSN 1996-0786 ... The Royal Niger Company--the chief instrument by ... burning within the image area. http://photojournal.jpl.nasa.gov/catalog/PIA03897. Figure 2 ...

  3. Improvement of antifungal and antibacterial antibiotic producing strain of Bacillus subtilis AFCI-69 by radiation and chemical mutagens. Part of a coordinated programme on radiation biology

    International Nuclear Information System (INIS)

    Ahmad, M.S.

    1978-08-01

    Gamma radiation was used to select higher antibiotic yield mutants of Bacillus subtilis AECL 69. The test organisms were Aspergillus niger RAGENI 70 and Staphylococcus aureus 6571 (16) N.C.T.C. Searches for fermentation, purification and characterization of antibiotics of parent strain and its mutants were carried out

  4. Bacillus subtilis genome diversity.

    Science.gov (United States)

    Earl, Ashlee M; Losick, Richard; Kolter, Roberto

    2007-02-01

    Microarray-based comparative genomic hybridization (M-CGH) is a powerful method for rapidly identifying regions of genome diversity among closely related organisms. We used M-CGH to examine the genome diversity of 17 strains belonging to the nonpathogenic species Bacillus subtilis. Our M-CGH results indicate that there is considerable genetic heterogeneity among members of this species; nearly one-third of Bsu168-specific genes exhibited variability, as measured by the microarray hybridization intensities. The variable loci include those encoding proteins involved in antibiotic production, cell wall synthesis, sporulation, and germination. The diversity in these genes may reflect this organism's ability to survive in diverse natural settings.

  5. Productive mutants of niger

    International Nuclear Information System (INIS)

    Misra, R.C.

    2001-01-01

    Seeds of six niger (Guizotia abyssinica Cass.) varieties ('GA-10', 'ONS-8', 'IGP-72', 'N-71', 'NB-9' and 'UN-4') were treated with 0.5, 0.75 and 1% ethyl methanesulphonate. After four generations of selection, 29 mutant lines were developed and those were evaluated from 1990-92 during Kharif (July to October) and Rabi (December to March) seasons. Average plant characteristics and yield data of four high yielding mutants along with 'IGP-76' (National Check), GA-10 (Zonal Check) and 'Semiliguda Local' (Local Check) are presented

  6. Areva in Niger

    International Nuclear Information System (INIS)

    2005-02-01

    Niger is the second poorest country in the world but it has natural resources underground in the form of uranium ores deposits. This uranium is currently mined by two companies incorporated under Nigerian law: Somair and Cominak, operated by the principal shareholder Areva (through its subsidiary Cogema). After a presentation of Somair and Cominak key figures, this document details the working conditions and radiological protection, the environmentally friendly operations, the production traceability, the local economic development, the strengthening of the health care system and the development of the infrastructure. (A.L.B.)

  7. Niger Delta Development Commission and Sustainable ...

    African Journals Online (AJOL)

    Niger Delta Development Commission and Sustainable Development of Niger Delta Region of Nigeria: The Case of Rivers State. Goddey Wilson. Abstract. The study is on Niger Delta Development Commission and sustainable development of Niger Delta region of Nigeria, the case of Rivers State. The main objective of the ...

  8. dbVar

    Data.gov (United States)

    U.S. Department of Health & Human Services — dbVar is a database of genomic structural variation. It accepts data from all species and includes clinical data. It can accept diverse types of events, including...

  9. Essential Bacillus subtilis genes

    DEFF Research Database (Denmark)

    Kobayashi, K.; Ehrlich, S.D.; Albertini, A.

    2003-01-01

    To estimate the minimal gene set required to sustain bacterial life in nutritious conditions, we carried out a systematic inactivation of Bacillus subtilis genes. Among approximate to4,100 genes of the organism, only 192 were shown to be indispensable by this or previous work. Another 79 genes were...... predicted to be essential. The vast majority of essential genes were categorized in relatively few domains of cell metabolism, with about half involved in information processing, one-fifth involved in the synthesis of cell envelope and the determination of cell shape and division, and one-tenth related...... to cell energetics. Only 4% of essential genes encode unknown functions. Most essential genes are present throughout a wide range of Bacteria, and almost 70% can also be found in Archaea and Eucarya. However, essential genes related to cell envelope, shape, division, and respiration tend to be lost from...

  10. Transcriptional profiling of Aspergillus niger

    OpenAIRE

    Veen, van der, D.

    2009-01-01

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

  11. Genetic analysis of Aspergillus niger

    OpenAIRE

    Debets, F.

    1990-01-01

    Dit proefschrift handelt over genetische analyse van de voor de biotechnologie belangrijke schimmel Aspergillusniger . A.niger is een imperfecte schimmel, met andere woorden A.niger heeft geen geslachtelijk stadium, en mist daardoor meiotische recombinatie. Toch is genetisch onderzoek aan imperfecte schimmels mogelijk en wel op basis van af en toe optredende mitotische recombinatie in heterozygote diploiden. Twee typen recombinanten zijn hierbij van belang. Ten eerste kunnen door opeenvolgend...

  12. Hvem var morderen?

    DEFF Research Database (Denmark)

    Andersen, Lene Vinther

    2014-01-01

    Folkemindesamleren og forfatteren Helene Strange (1874-1943) skrev flere gange om et giftmord på en præst på Nordfalster i 1755. Hun satte spørgsmålstegn ved højesteretsdommen og hævdede, at en uskyldig pige blev dømt, mens den virkelige morder slap fri. Det var folkets uskrevne dom, som i over...... hundrede år var blevet fortalt mundtligt videre på egnen, og hun forsøgte – med forskellige midler – at få bragt denne version af historien frem i offentligheden....

  13. Paulus var kristendommens Lenin

    DEFF Research Database (Denmark)

    Thyssen, Ole

    2017-01-01

    En af Luthers inspirationskilder var Paulus, hvis løsning på lokale problemer fik globale konsekvenser. Han trak en skarp grænse mellem det snavsede kød og den rene sjæl og mellem vantro og tro.......En af Luthers inspirationskilder var Paulus, hvis løsning på lokale problemer fik globale konsekvenser. Han trak en skarp grænse mellem det snavsede kød og den rene sjæl og mellem vantro og tro....

  14. Cadmium biosorption by Aspergillus niger; Biossorcao de cadmio pelo Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Silva, E.P.; Barros Junior, L.M.; Duarte, M.M.L.; Macedo, G.R. [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil)]. E-mail: edmilson@eq.ufrn.br

    2003-07-01

    Biosorption is a property of certain types of inactive, dead, microbial biomass to bind and concentrate heavy metals from even very dilute aqueous solutions. Biomass exhibits this property, acting just as a chemical substance, as an ion exchanger of biological origin. It is particularly the cell wall structure of certain algae, fungi and bacteria which was found responsible for this phenomenon. Some of the biomass types come as a waste by-product of large-scale industrial fermentations (the mold Rhizopus or the bacterium Bacillus subtilis). Other metal-binding biomass types, certain abundant seaweeds (particularly brown algae e.g. Sargassum, Ecklonia), can be readily collected from the oceans. These biomass types, serving as a basis for metal biosorption processes, can accumulate in excess of 25% of their dry weight in deposited heavy metals: Pb, Cd, U, Cu, Zn, even Cr and others. Sorption experiments using the Aspergillus niger fungus for cadmium removal were carried out to study the factors influencing and optimizing the biosorption of this metal. The effects of pH, time, biomass concentration, and initial concentration of the heavy metal on the rate of metallic biosorption were examined. (author)

  15. Niger republic mineral planning ( part two): actual state of Niger republic geological knowledge

    International Nuclear Information System (INIS)

    Joo, Julien; Franconi, A.

    1983-01-01

    In this document, the followings points are described: available scientific supports basicly use for mining and geological research; geological history outline of Niger republic and west Africa; crystalline fields of liptako-gourma (western part of Niger); air massif; southern Niger crystalline (Damagaram-Mounio, and southern Maradi); Primary , secondary and tertiary formations of Niger western sedimentary basin and eastern Niger crystalline socle and phanerozoic formation [fr

  16. Lysine aminopeptidase of Aspergillus niger

    OpenAIRE

    Basten, D.E.J.W.; Visser, J.; Schaap, P.J.

    2001-01-01

    Conserved regions within the M1 family of metallo-aminopeptidases have been used to clone a zinc aminopeptidase from the industrially used fungus Aspergillus niger. The derived amino acid sequence of ApsA is highly similar to two yeast zinc aminopeptidases, LAPI and AAPI (53.3 and 50.9␘verall similarity, respectively), two members of the M1 family of metallo-aminopeptidases. The encoding gene was successfully overexpressed in A. niger and the overexpressed product was purified and characteriz...

  17. Pêcheurs nomades du fleuve Niger

    DEFF Research Database (Denmark)

    Hahonou, Eric Komlavi

    2017-01-01

    Following Jean Rouch's travel on the Niger river and his first writings on the Sorkawa fishermen of Kebbi, the article documents the trajectory of a group of nomadic fishermen engaged in seasonal campaigns on the Niger river between Nigeria and Mali. The author retraces the evolution of fishermen...... in the process of sedentarisation of these fishermen. Sedentarisation goes hand in hand with impoverishment. Such trajectory is documented by a documentary movie, river Nomads (2016), starting point of a research at the crossroads of circular migrations and an anthropology of citizenship. This research agenda...

  18. Nitrile biotransformation by Aspergillus niger

    Czech Academy of Sciences Publication Activity Database

    Šnajdrová, Radka; Kristová, Veronika; Crestia, D.; Nikolaou, K.; Kuzma, Marek; Lemaire, M.; Gallienne, E.; Bolte, J.; Bezouška, K.; Křen, Vladimír; Martínková, Ludmila

    2004-01-01

    Roč. 29, - (2004), s. 227-232 ISSN 1381-1177 R&D Projects: GA MŠk OC D25.002; GA AV ČR IAA4020213 Institutional research plan: CEZ:AV0Z5020903 Keywords : aspergillus niger * nitrile-converting enzymes * nitrile hydratase Subject RIV: EE - Microbiology, Virology Impact factor: 1.547, year: 2004

  19. Biotransformation of the streptomyces scabies phytotoxin thaxtomin A by the fungus aspergillus niger

    International Nuclear Information System (INIS)

    Lazarovits, G.; Hill, J.; King, R.; Calhoun, L.A.

    2004-01-01

    Of several hundred microorganisms randomly selected from the environment, only a fungal isolate identified as Aspergillus niger van Tiegham var. niger was found to transform the phytotoxin thaxtomin A to much less toxic metabolites. The rate and extent of transformation of thaxtomin A was tested under a variety of conditions, including different growth media, biomass concentrations, incubation periods, and shaker speeds. Under optimum conditions the fungus converted thaxtomin A into two major and five minor metabolites. The two major metabolites and three of the five minor metabolites were fully characterized by a combination of mass spectral and nuclear magnetic resonance techniques. When assayed on aseptically produced mini-tubers, the major metabolites proved to be much less phytotoxic than thaxtomin A. (author)

  20. Biotransformation of the streptomyces scabies phytotoxin thaxtomin A by the fungus aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Lazarovits, G.; Hill, J. [Agriculture and Agri-Food Canada, Southern Crop Protection and Food Research Centre, London, Ontario (Canada)]. E-mail: Lazarovitsg@agr.gc.ca; King, R. [Agriculture and Agri-Food Canada, Potato Research Centre, Fredericton, New Brunswick (Canada); Calhoun, L.A. [Univ. of New Brunswick, Dept. of Chemistry, Fredericton, New Brunswick (Canada)

    2004-07-01

    Of several hundred microorganisms randomly selected from the environment, only a fungal isolate identified as Aspergillus niger van Tiegham var. niger was found to transform the phytotoxin thaxtomin A to much less toxic metabolites. The rate and extent of transformation of thaxtomin A was tested under a variety of conditions, including different growth media, biomass concentrations, incubation periods, and shaker speeds. Under optimum conditions the fungus converted thaxtomin A into two major and five minor metabolites. The two major metabolites and three of the five minor metabolites were fully characterized by a combination of mass spectral and nuclear magnetic resonance techniques. When assayed on aseptically produced mini-tubers, the major metabolites proved to be much less phytotoxic than thaxtomin A. (author)

  1. Carbohydrate metabolism in Bacillus subtilis

    International Nuclear Information System (INIS)

    Riedel, K.

    1980-01-01

    The glucose metabolism via the glycolytic pathway as well as via the oxidative and inoxidative hexose monophosphate pathways in Bacillus subtilis was studied applying 1- 14 C- and 6- 14 C-glucose, respectively, and determining labelled CO 2 and RNA. A method for calculating the catabolic pathways was developed. In nonproliferating cultures glucose is catabolized to 62% via the glycolytic pathway, to 20% via the oxidative, and to 18% via the inoxidative pathway

  2. Hyphal heterogeneity in Aspergillus niger

    OpenAIRE

    de Bekker, A.M.

    2011-01-01

    Mycelial fungi use hyphae to colonize substrates. These hyphae secrete enzymes that convert complex polymers into breakdown products that can be taken up to serve as nutrients. Using GFP as a reporter it has been shown that exploring hyphae of Aspergillus niger are heterogenic with respect to expression of the glucoamylase gene glaA; some hyphae strongly express the glucoamylase gene glaA, while others express it lowly. This was a surprising finding considering the fact that all hyphae were e...

  3. Germination of Aspergillus niger conidia

    OpenAIRE

    Hayer, Kimran

    2014-01-01

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

  4. Regulatory processes in Aspergillus niger

    OpenAIRE

    Poulsen, Lars; Thykær, Jette; Eliasson Lantz, Anna

    2012-01-01

    Filamentous fungi are extensively used in the fermentation industry for synthesis of numerous products. One of the most important, is the fungus Aspergillus niger, used industrially for production of organic acids, and homologous as well as heterologous enzymes. This fungus has numerous of advantages, including tolerance for low pH, which is important for acid production. Furthermore, it has the capability of metabolizing a wide variety of carbon sources, possesses an exceptional efficient pr...

  5. Ecology and genomics of Bacillus subtilis.

    Science.gov (United States)

    Earl, Ashlee M; Losick, Richard; Kolter, Roberto

    2008-06-01

    Bacillus subtilis is a remarkably diverse bacterial species that is capable of growth within many environments. Recent microarray-based comparative genomic analyses have revealed that members of this species also exhibit considerable genomic diversity. The identification of strain-specific genes might explain how B. subtilis has become so broadly adapted. The goal of identifying ecologically adaptive genes could soon be realized with the imminent release of several new B. subtilis genome sequences. As we embark upon this exciting new era of B. subtilis comparative genomics we review what is currently known about the ecology and evolution of this species.

  6. Management of Meloidogyne incognita race 3 and Macrophomina phaseolina by fungus culture filtrates and Bacillus subtilis on chickpea

    OpenAIRE

    Siddiqui, Z.A.; Mahmood, I.

    1995-01-01

    #Bacillus subtilis$ et des filtrats de culture des champignons #Aspergillus niger, Curvularia tuberculata$ et #Penicillium coryophilum$ ont été utilisés, seuls ou en combinaison, comme traitement de semences pour protéger le pois chiche contre une maladie racinaire complexe associant le nématode "Meloidogyne incognita$ race 3 et le champignon #Macrophomina phaseolina$. D'une manière générale, les traitements à l'aide de ces quatre agents, seuls ou en combinaison, accroissent le poids sec et l...

  7. Biotransformation of Stypotriol triacetate by Aspergillus niger

    Science.gov (United States)

    Areche, Carlos; Vaca, Inmaculada; Labbe, Pamela; Soto-Delgado, Jorge; Astudillo, Luis; Silva, Mario; Rovirosa, Juana; San-Martin, Aurelio

    2011-07-01

    Biological transformation of the meroditerpenoid, stypotriol triacetate ( 1) by the fungi Aspergillus niger, Cunninghamella elegans, Gibberella fujikuroi and Mucor plumbeus was studied. The incubation of 1 with A. niger yielded the new compound 6',14-diacetoxy-stypol-4,5-dione ( 2) whose structure was established by 1H, 13C and 2D NMR and supported by DFT/GIAO.

  8. Type I signal peptidases of Bacillus subtilis

    NARCIS (Netherlands)

    Tjalsma, Harold; Bolhuis, Albert; Bron, Sierd; Jongbloed, Jan; Meijer, Wilfried J.J.; Noback, Michiel; van Roosmalen, Maarten; Venema, Gerhardus; van Dijl, Jan Maarten; Hopsu Havu, VK; Jarvinen, M; Kirschke, H

    1997-01-01

    Bacillus subtilis contains at least three chromosomally-encoded type I signal peptidases (SPases; SipS, SipT, and SipU), which remove signal peptides from secretory proteins. In addition, certain B. subtilis (natto) strains contain plasmid-encoded type I SPases (SipP). The known type I SPases from

  9. Organic acid production by Aspergillus niger

    DEFF Research Database (Denmark)

    Jongh, Wian de

    2006-01-01

    . Specielt Aspergillus niger er interessant i forbindelse med produktion af organiske syrer, idet denne organisme tolerer lavt pH, kan give høje produktudbytter, og kan give høje produktiviteter som allerede illustreret i anvendelsen af denne organisme i produktionen af citronsyre. Disse faktorer gør A....... niger til en ideel kandidat for metabolic engineering, men anvendelsen af metabolic engineering til at udvikle en A. niger cellefabrik der producerer forskellige organiske syrer har været begrænset af vores kendskab til metabolismen og dens regulering i denne organisme. Formålet med dette Ph.D. stadium...... intracellulære metabolitter samt kontinuert fermentering af A. niger. Ved anvendelse af metabolic engieering lykkedes det at udvikle nogle stammer af A. niger der havde forbedret produktion af citrat. Mekanismerne bag de forbedrede produktiviteter blev undersøgt og resultaterne heraf er diskuteret i afhandlingen...

  10. [Progress in omics research of Aspergillus niger].

    Science.gov (United States)

    Sui, Yufei; Ouyang, Liming; Lu, Hongzhong; Zhuang, Yingping; Zhang, Siliang

    2016-08-25

    Aspergillus niger, as an important industrial fermentation strain, is widely applied in the production of organic acids and industrial enzymes. With the development of diverse omics technologies, the data of genome, transcriptome, proteome and metabolome of A. niger are increasing continuously, which declared the coming era of big data for the research in fermentation process of A. niger. The data analysis from single omics and the comparison of multi-omics, to the integrations of multi-omics based on the genome-scale metabolic network model largely extends the intensive and systematic understanding of the efficient production mechanism of A. niger. It also provides possibilities for the reasonable global optimization of strain performance by genetic modification and process regulation. We reviewed and summarized progress in omics research of A. niger, and proposed the development direction of omics research on this cell factory.

  11. The Niger Delta Amnesty Program

    Directory of Open Access Journals (Sweden)

    Benjamin A. Okonofua

    2016-06-01

    Full Text Available The armed conflict between militias and government forces in Nigeria’s Niger Delta region has spanned for more than two decades, defying all solutions. A disarmament, demobilization, and reintegration (DDR program was established in August 2015 in effort to end the violence and has remained in place. It is a radically different approach from past approaches that displayed zero tolerance to all political challenges to oil production or the allocation of oil profits. The approach appeared to be immediately successful in that it forced a ceasefire, engaged militants in planned programs to rehabilitate and reintegrate them into civilian society, and opened up the oil wells (many of which had been shut due to the crisis with the effect of increasing government revenue, which depends 85% on oil exports. Yet, few studies have attempted to understand the dynamics within the country that are responsible for the design and implementation of this broad policy shift or to understand whether and how the current initiative is able to end the conflict and institute peace beyond the short term. This study, therefore, is important because it provides a critical perspective that anticipates and explains emerging issues with the Niger Delta Amnesty Program, which have implications for DDR adaptation and implementation all over the world. Ultimately, the research demonstrates how the DDR program both transforms the Niger Delta conflict and becomes embroiled in intense contestations not only about the mechanism for transforming the targeted population but also whether and how the program incorporates women who are being deprioritized by the program.

  12. Da Danmark var en slavenation

    DEFF Research Database (Denmark)

    Peters, Rikke Louise Alberg; Brunbech, Peter Johan Yding; Poulsen, Jens Aage

    I mere end 250 år var Danmark en stor kolonimagt. Skt. Jan, Skt. Thomas og Skt. Croix, eller U.S. Virgin Islands, som de kaldes i dag, var danske kolonier, hvor der bl.a. blev dyrket sukkerrør og bomuld. Det hårde arbejde blev udført af slaver, som man fra slutningen af 1600-tallet begyndte at tr...

  13. var. puiggarianum (Batrachospermales, Rhodophyta

    Directory of Open Access Journals (Sweden)

    María Cecilia Gauna

    2005-01-01

    Full Text Available Se coleccionó Batrachospermum atrum var. puiggarianum por primera vez en la provincia de Buenos Aires. La identificación de las muestras se basó en el análisis de la morfología microscópica y en el número cromosómico de cada una de las generaciones de su ciclo de vida bajo cultivo. Los talos se estudiaron con microscopio óptico, y la cariología, por medio de la técnica de carmín acético. El ciclo de vida presentó tres generaciones: una gametofítica haploide, una carposporófitica diploide que originó la última fase Chantransia diploide. Los talos gametófitos estuvieron formados por verticilos separados por zonas internodales, cada uno de ellos constituidos por ramas primarias densamente comprimidas. Entre éstas se observaron ramas portadoras de espermatangios y de carpogonios. Las zonas internodales estuvieron constituidas por células corticales y axiales. Los carposporófitos ovoideos estuvieron formados por filamentos gonimoblásticos portadores de carposporangios terminales. El estado Chantransia se caracterizó por presentar filamentos cortos con pocas células. El material estudiado presentó un número haploide n = 4 y diploide 2n = 8.

  14. Pirated Siderophores Promote Sporulation in Bacillus subtilis.

    Science.gov (United States)

    Grandchamp, Gabrielle M; Caro, Lews; Shank, Elizabeth A

    2017-05-15

    In microbial communities, bacteria chemically and physically interact with one another. Some of these interactions are mediated by secreted specialized metabolites that act as either intraspecies or interspecies signals to alter gene expression and to change cell physiology. Bacillus subtilis is a well-characterized soil microbe that can differentiate into multiple cell types, including metabolically dormant endospores. We were interested in identifying microbial interactions that affected sporulation in B. subtilis Using a fluorescent transcriptional reporter, we observed that coculturing B. subtilis with Escherichia coli promoted sporulation gene expression via a secreted metabolite. To identify the active compound, we screened the E. coli Keio Collection and identified the sporulation-accelerating cue as the siderophore enterobactin. B. subtilis has multiple iron acquisition systems that are used to take up the B. subtilis- produced siderophore bacillibactin, as well as to pirate exogenous siderophores such as enterobactin. While B. subtilis uses a single substrate binding protein (FeuA) to take up both bacillibactin and enterobactin, we discovered that it requires two distinct genes to sporulate in response to these siderophores (the esterase gene besA for bacillibactin and a putative esterase gene, ybbA , for enterobactin). In addition, we found that siderophores from a variety of other microbial species also promote sporulation in B. subtilis Our results thus demonstrate that siderophores can act not only as bacterial iron acquisition systems but also as interspecies cues that alter cellular development and accelerate sporulation in B. subtilis IMPORTANCE While much is known about the genetic regulation of Bacillus subtilis sporulation, little is understood about how other bacteria influence this process. This work describes an interaction between Escherichia coli and B. subtilis that accelerates sporulation in B. subtilis The interaction is mediated by the E

  15. niger

    African Journals Online (AJOL)

    three hundred and eighty four (384) blood samples have been collected in dried test tubes and anti- coagulant test tubes (EDTA). .... Dans les troupeaux, les individus ont été sélectionnés selon un sondage systé- matique. PRELEVEMENTS. Les prélèvements sanguins ont été réalisés au niveau de la veine jugulaire des ...

  16. Regulatory processes in Aspergillus niger

    DEFF Research Database (Denmark)

    Poulsen, Lars

    characteristics, as a lower oxalic ii acid formation and wild type growth performance; it was therefore argued that this strain could be an attractive alternative to ΔprtT. Finally, in order to characterize the formation of the carcinogenic mycotoxin fumonisin, a reporter strain of A. niger was constructed, where...... the promoter from the fumonisin synthase was fused to the green fluorescent protein. This strain was used together with the commercial large-scale nutrient profiling platform, Biolog Phenotype MicroArrays. Out of the 476 conditions tested, six compounds significantly induce fumonisin production, identified....... These formed the basis for the subsequent examinations, which resulted in the identification of azelaic acid, a plant hormone and a very potent fumonisin inducer....

  17. Tannase Production by Aspergillus niger

    Directory of Open Access Journals (Sweden)

    N. Lokeswari

    2007-01-01

    Full Text Available A method for assay of microbial tannase (Tannin acyl hydrolase based on the formation of chromogen between gallic acid and rhodanine is reported. Maximum Tannase production occurred in the culture broth containing 1-2% (w/v tannic acid and 0.05 – 0.1% (w/v glucose. The pH, incubation period, temperature and Glucose concentration optima of Tannase production was found at 5.5, 36 h, 35°C and 0.5% respectively. These properties make the enzyme suitable for pollution control and bioprocess industry. This assay is very simple, reproducible, and very convenient, and with it Tannase activity can be measured in relation to the growth of the organism. Aspergillus niger exhibited higher enzyme activity showing about 65 mole percent conversion respectively after a 36 h incubation period. The assay is complete in a short time, very convenient and reproducible.

  18. Measurement of the CP-violation parameter Re(var-epsilon '/var-epsilon)

    International Nuclear Information System (INIS)

    Gibbons, L.K.; Barker, A.R.; Briere, R.A.; Makoff, G.; Papadimitriou, V.; Patterson, J.R.; Schwingenheuer, B.; Somalwar, S.V.; Wah, Y.W.; Winstein, B.; Winston, R.; Woods, M.; Yamamoto, H.; Swallow, E.C.; Bock, G.J.; Coleman, R.; Enagonio, J.; Hsiung, Y.B.; Ramberg, E.; Stanfield, K.; Tschirhart, R.; Yamanaka, T.; Gollin, G.D.; Karlsson, M.; Okamitsu, J.K.; Debu, P.; Peyaud, B.; Turlay, R.; Vallage, B.

    1993-01-01

    A measurement of the CP-violation parameter Re(var-epsilon '/var-epsilon) has been made using the full E731 data set. We find Re(var-epsilon '/var-epsilon)=(7.4±5.2±2.9)x10 -4 where the first error is statistical and the second systematic

  19. NUTRIENT COMPOSITION OF NIGER SEED (GUIZOTIA ...

    African Journals Online (AJOL)

    B. S. Chandravanshi

    fiber. Niger oil has a fatty acid composition typical for seed oils of the .... system using external calibration curve after optimizing the parameters in to .... physical and chemical properties of the soil, application of natural (manure) and artificial.

  20. Niger institute focuses on financial accountability | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2016-04-28

    Apr 28, 2016 ... Niger institute focuses on financial accountability ... on renewing outdated financial management systems that impeded effective management and reporting on its activities. ... Canada-Africa grants spur novel ideas, networks.

  1. AMNESTY IN THE NIGER DELTA: VERTICAL MOVEMENT ...

    African Journals Online (AJOL)

    OLAWUYI

    federal government, the Niger Delta communities claim that they are entitled to ... instability, macroeconomic challenges, inconsistent policy regimes to ..... continues they cannot threaten the stability of the country nor affect its continued.

  2. Assessment of Aspergillus niger biofilm growth kinetics in ...

    African Journals Online (AJOL)

    Jane

    2011-10-12

    Oct 12, 2011 ... other hand, A. niger biofilm growth followed a logistic model having higher maximal specific growth rate than ...... Growth estimation of Aspergillus oryzae cultured on ... Initial intracellular proteome profile of Aspergillus niger.

  3. The Economic Dimensions of the Niger Delta Ethnic Conflicts (Pp ...

    African Journals Online (AJOL)

    User

    1970, the price of international oil stepped upwards following the Middle. Eastern Yom Kippur .... Over the years, the pleas of the Niger Delta people for accommodation are ignored or .... In a labour surplus region like the Niger Delta, budget.

  4. Extracellular signaling and multicellularity in Bacillus subtilis.

    Science.gov (United States)

    Shank, Elizabeth Anne; Kolter, Roberto

    2011-12-01

    Bacillus subtilis regulates its ability to differentiate into distinct, co-existing cell types in response to extracellular signaling molecules produced either by itself, or present in its environment. The production of molecules by B. subtilis cells, as well as their response to these signals, is not uniform across the population. There is specificity and heterogeneity both within genetically identical populations as well as at the strain-level and species-level. This review will discuss how extracellular signaling compounds influence B. subtilis multicellularity with regard to matrix-producing cannibal differentiation, germination, and swarming behavior, as well as the specificity of the quorum-sensing peptides ComX and CSF. It will also highlight how imaging mass spectrometry can aid in identifying signaling compounds and contribute to our understanding of the functional relationship between such compounds and multicellular behavior. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Protein-Tyrosine Phosphorylation in Bacillus subtilis

    DEFF Research Database (Denmark)

    Mijakovic, Ivan; Petranovic, Dina; Bottini, N.

    2005-01-01

    phosphorylation, indicating that this post-translational modifi cation could regulate physiological processes ranging from stress response and exopolysaccharide synthesis to DNA metabolism. Some interesting work in this fi eld was done in Bacillus subtilis , and we here present the current state of knowledge...... on protein-tyrosine phosphorylation in this gram-positive model organism. With its two kinases, two kinase modulators, three phosphatases and at least four different tyrosine-phosphorylated substrates, B. subtilis is the bacterium with the highest number of presently known participants in the global network...

  6. On the safety of Aspergillus niger - a review

    DEFF Research Database (Denmark)

    Schuster, E.; Dunn-Coleman, N.; Frisvad, Jens Christian

    2002-01-01

    Aspergillus niger is one of the most important microorganisms used in biotechnology. It has been in use already for many decades to produce extracellular (food) enzymes and citric acid. In fact, citric acid and many A. niger enzymes are considered GRAS by the United States Food and Drug...... retrieval reasons and there is a taxonomical consensus based on molecular data that the only other common species closely related to A. niger in the Aspergillus series Nigri is A. tubingensis. A. niger, like other filamentous fungi, should be treated carefully to avoid the formation of spore dust. However...... Administration. In addition, A. niger is used for biotransformations and waste treatment. In the last two decades, A. niger has been developed as an important transformation host to over-express food enzymes. Being pre-dated by older names, the name A. niger has been conserved for economical and information...

  7. Isolation and characterization of radioresistant mutants in Bacillus subtilis and Bacillus thuringiensis

    International Nuclear Information System (INIS)

    Kalinin, V.L.; Petrov, V.N.; Petrova, T.M.

    1981-01-01

    Vegetative cells of Bac. thuringiensis var. galleriae (the wild-type strain 351) are much more sensitive to lethal effects of UV light and 60 Co-γ-rays than those of Bac. subtilis (the wild-type strain 168). This difference is less pronounced for spores of these strains. By means of repeated γ-irradiation-regrowth cycles radioresistant mutants Bac. thuringiensis Gamsup(r) 14 and Bac. subtilis Gamsup(r) 9 were selected. The vegetative cells of these mutants are correspondingly 19 times and 3.9 times more resistant to lethal effects of γ-radiation than the cells of the parental strains. The resistance of the Gamsup(r) mutant cells to lethal effects of UV light and H 2 O 2 is also increased. The spores of the Gamsup(r) 14 mutant are 1.5-1.7 times more resistant to γ-radiation and UV light than the wild-type spores. The radioresistant mutants and the parental strains do not vary in their capacity for host-cell reactivation of UV- or γ-irradiated phages Tg13 and 105

  8. Bacillus subtilis biofilm induction by plant polysaccharides.

    Science.gov (United States)

    Beauregard, Pascale B; Chai, Yunrong; Vlamakis, Hera; Losick, Richard; Kolter, Roberto

    2013-04-23

    Bacillus subtilis is a plant-beneficial Gram-positive bacterium widely used as a biofertilizer. However, relatively little is known regarding the molecular processes underlying this bacterium's ability to colonize roots. In contrast, much is known about how this bacterium forms matrix-enclosed multicellular communities (biofilms) in vitro. Here, we show that, when B. subtilis colonizes Arabidopsis thaliana roots it forms biofilms that depend on the same matrix genes required in vitro. B. subtilis biofilm formation was triggered by certain plant polysaccharides. These polysaccharides served as a signal for biofilm formation transduced via the kinases controlling the phosphorylation state of the master regulator Spo0A. In addition, plant polysaccharides are used as a source of sugars for the synthesis of the matrix exopolysaccharide. The bacterium's response to plant polysaccharides was observed across several different strains of the species, some of which are known to have beneficial effects on plants. These observations provide evidence that biofilm genes are crucial for Arabidopsis root colonization by B. subtilis and provide insights into how matrix synthesis may be triggered by this plant.

  9. The methionine salvage pathway in Bacillus subtilis

    Directory of Open Access Journals (Sweden)

    Danchin Antoine

    2002-04-01

    Full Text Available Abstract Background Polyamine synthesis produces methylthioadenosine, which has to be disposed of. The cell recycles it into methionine through methylthioribose (MTR. Very little was known about MTR recycling for methionine salvage in Bacillus subtilis. Results Using in silico genome analysis and transposon mutagenesis in B. subtilis we have experimentally uncovered the major steps of the dioxygen-dependent methionine salvage pathway, which, although similar to that found in Klebsiella pneumoniae, recruited for its implementation some entirely different proteins. The promoters of the genes have been identified by primer extension, and gene expression was analyzed by Northern blotting and lacZ reporter gene expression. Among the most remarkable discoveries in this pathway is the role of an analog of ribulose diphosphate carboxylase (Rubisco, the plant enzyme used in the Calvin cycle which recovers carbon dioxide from the atmosphere as a major step in MTR recycling. Conclusions A complete methionine salvage pathway exists in B. subtilis. This pathway is chemically similar to that in K. pneumoniae, but recruited different proteins to this purpose. In particular, a paralogue or Rubisco, MtnW, is used at one of the steps in the pathway. A major observation is that in the absence of MtnW, MTR becomes extremely toxic to the cell, opening an unexpected target for new antimicrobial drugs. In addition to methionine salvage, this pathway protects B. subtilis against dioxygen produced by its natural biotope, the surface of leaves (phylloplane.

  10. Association of RNAs with Bacillus subtilis Hfq.

    Directory of Open Access Journals (Sweden)

    Michael Dambach

    Full Text Available The prevalence and characteristics of small regulatory RNAs (sRNAs have not been well characterized for Bacillus subtilis, an important model system for Gram-positive bacteria. However, B. subtilis was recently found to synthesize many candidate sRNAs during stationary phase. In the current study, we performed deep sequencing on Hfq-associated RNAs and found that a small subset of sRNAs associates with Hfq, an enigmatic RNA-binding protein that stabilizes sRNAs in Gram-negatives, but whose role is largely unknown in Gram-positive bacteria. We also found that Hfq associated with antisense RNAs, antitoxin transcripts, and many mRNA leaders. Several new candidate sRNAs and mRNA leader regions were also discovered by this analysis. Additionally, mRNA fragments overlapping with start or stop codons associated with Hfq, while, in contrast, relatively few full-length mRNAs were recovered. Deletion of hfq reduced the intracellular abundance of several representative sRNAs, suggesting that B. subtilis Hfq-sRNA interactions may be functionally significant in vivo. In general, we anticipate this catalog of Hfq-associated RNAs to serve as a resource in the functional characterization of Hfq in B. subtilis.

  11. The Regulatory RNAs of Bacillus subtilis

    NARCIS (Netherlands)

    Mars, Ruben

    2014-01-01

    In vrijwel alle organismen wordt RNA aangemaakt dat niet codeert voor eiwit, maar een regulerende functie heeft. Dit proefschrift beschrijft de identificatie van ~1600 nieuwe potentiële regulatie-RNAs in de bodembacterie Bacillus subtilis die veel voor biotechnologische toepassingen ingezet wordt.

  12. The Cell Wall of Bacillus subtilis

    NARCIS (Netherlands)

    Scheffers, Dirk-Jan; Graumann, Peter

    2012-01-01

    The cell wall of Bacillus subtilis is a rigid structure on the outside of the cell that forms the first barrier between the bacterium and the environment, and at the same time maintains cell shape and withstands the pressure generated by the cell’s turgor. In this chapter, the chemical composition

  13. The Aspergillus niger RmsA protein

    Science.gov (United States)

    Minkwitz, Susann; Schütze, Tabea; van den Hondel, Cees A.M.J.J; Ram, Arthur F.J

    2010-01-01

    Many cells and organisms go through polarized growth phases during their life. Cell polarization is achieved by local accumulation of signaling molecules which guide the cytoskeleton and vesicular trafficking to specific parts of the cell and thus ensure polarity establishment and maintenance. Polarization of signaling molecules is also fundamental for the lifestyle of filamentous fungi such as Aspergillus niger and essential for their morphogenesis, development and survival under environmental stress conditions. Considerable advances in our understanding on the protagonists and processes mediating polarized growth in filamentous fungi have been made over the past years. However, how the interplay of different signaling pathways is coordinated has yet to be determined. We found that the A. niger RmsA protein is central for the polarization of actin at the hyphal tip but also of vital importance for the metabolism, viability and stress resistance of A. niger. This suggests that RmsA could occupy an important position in the global network of pathways that balance growth, morphogenesis and survival of A. niger. PMID:20585521

  14. Chronic necrotising pneumonia caused by Aspergillus niger.

    Science.gov (United States)

    Wiggins, J; Clark, T J; Corrin, B

    1989-01-01

    A woman with asthma developed chronic necrotising semi-invasive pneumonia due to mixed Aspergillus niger and Candida albicans infection; though not severely immunosuppressed, she may have been predisposed by long term oral corticosteroid and recurrent oral antibiotic treatment. The diagnosis should be considered in patients with chronic airflow limitation who develop cavitating pneumonia. Images PMID:2763249

  15. Analcite formation in the Agades Region (Niger)

    International Nuclear Information System (INIS)

    1966-06-01

    A study based mainly upon field mapping and drill cores examination, followed by a laboratory survey allows us to support a genetic hypothesis upon the formation of analcime in the 'Continental intercalaire' of Agades (Niger). Analcime could be generated from an early diagenesis of argillaceous sediments influenced by high soda content fossil waters inside confined continental sedimentary basins. (authors) [fr

  16. Characterisation of Aspergillus niger prolyl aminopeptidase

    NARCIS (Netherlands)

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

    2005-01-01

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

  17. Bioluminescent hydrocarbonclastic bacteria of the Niger Delta ...

    African Journals Online (AJOL)

    Utilization of three petroleum hydrocarbons (Mobil SAE 40 Engine Oil, Diesel and Bonny light Crude Oil) by four bioluminescent bacteria (Vibrio harveyi, V. fisheri, Photobacterium leiognathi and P. Phosphoreum isolated from the Bonny estuary in the Niger Delta, Nigeria was investigated. Microbial utilization was monitored ...

  18. CONFLICT RESOLUTION THROUGH DIALOGUE IN THE NIGER ...

    African Journals Online (AJOL)

    imitch

    sea are Rivers forcados, marking the Western boundary of Bayelsa State, and St. ... sandy, porous and salty soil, too much rainfall, agricultural land .... media reports that the leaders of the Niger Delta have rejected Alhaji Ibrahim Gambari as the government ... continues to flow to enrich other people across the country …

  19. Efecto del ácido acetil salicílico y Bacillus subtilis en la infección causada por Cucumber mosaic virus en calabacita

    Directory of Open Access Journals (Sweden)

    E. Maldonado-Cruz

    2008-01-01

    Full Text Available Dos conocidos agentes inductores de resistencia en las plantas, ácido acetil salicílico y Bacillus subtilis, fueron evaluados con la finalidad de conocer su efecto en la infección causada por el Cucumber mosaic virus (CMV en Cucurbita pepo var. Zucchini grey.Se estableció un diseño experimental completamente al azar en invernadero con cinco tratamientos y ocho repeticiones: Bacillus subtilis aplicado al suelo, B. subtilis aplicado al follaje; B. subtilis aplicado al suelo y al follaje, ácido acetil salicílico aplicado al follaje y testigo (sin aplicación de ninguno de los productos antes indicados. Plantas de 20 días de edad fueron inoculadas mecánicamente con Cucumber mosaic virus y 15 días después de la inoculación se evaluaron las variables peso de biomasa fresca y concentración viral mediante la técnica de DAS-ELISA. Los resultados muestran que las plantas inoculadas con B. subtilis al suelo y ácido acetil salicílico tuvieron significativamente mayor peso de biomasa fresca comparados con el tratamiento Testigo (P¿0.05. Las plantas de todos los tratamientos donde se aplicó B. subtilis (al suelo, al follaje o al suelo y al follaje tuvieron una concentración viral significativamente menor comparadas con el testigo (P¿0.05 en la prueba de ELISA.

  20. Recent Niger Delta shoreline response to Niger River hydrology: Conflict between forces of Nature and Humans

    Science.gov (United States)

    Dada, Olusegun A.; Li, Guangxue; Qiao, Lulu; Asiwaju-Bello, Yinusa Ayodele; Anifowose, Adeleye Yekini Biodun

    2018-03-01

    The Niger River Delta is a prolific hydrocarbon province and a mega-delta of economic and environmental relevance. To understand patterns of its recent shoreline evolution (1923-2013) in response to the Niger River hydrology, and establish the role played by forces of Nature and Human, available topographic and satellite remote sensing data, combined with hydro-climatic (rainfall and runoff) data were analyzed. Results indicate that the entire delta coastline dramatically receded: 82% of the >400 km-long coast retreated, during the period 1950-1987; and 69% between 2007 and 2012. Prior to 1950, there was a continuation of seaward advancement along 53-74% of the delta coast. The 1950-1987 shoreline recession coincided with occurrences of two major events in the Niger River basin; these are downward trends in hydro-climatic conditions (the great droughts of the 1970s-1980s), and dam construction on the Lower Niger River at Kainji (1964-1968). The 2007-2012 event corresponded with the extensive channel dredging during 2009-2012 in the Lower Niger River from the coastal town of Warri in the south to Baro in the north. Remarkably, the largest net shoreline advancement recorded in 74% of the entire delta area occurred within a year (2012-2013), which we link to increased sediment supply to the coast caused by the '2012' floods, adjudged the worst floods in the entire Niger River Basin in the last few decades. With both anthropogenic and environmental factors inducing delta evolution, only innovative river and coastal management can determine the fortune of the future coastal development of the Niger Delta.

  1. BIOLOGICAL CONTROL OF BANDED LEAF AND SHEATH BLIGHT DISEASE (Rhizoctonia solani KUHN IN CORN WITH FORMULATED Bacillus subtilis BR23

    Directory of Open Access Journals (Sweden)

    Amran Muis

    2016-10-01

    Full Text Available Rhizoctonia solani Kuhn. causing banded leaf and sheath blight diseases is one of the important fungi of corn world wide. The fungus is commonly controlled by using fungicide because no resistant variety available. The objective of the study was to develop a seed treatment formulation of the selected Bacillus subtilis to control R. solani in corn. The study was conducted in the Department of Plant Pathology, College of Agriculture, University of the Philippines Los Bañòs, College, Laguna from May 2004 to August 2005, using sweet corn var. IPB Supersweet as test plant. Corn seeds were surface sterilized for 10 minutes in 1% sodium hypochlorite solution and 5% ethanol, washed thrice with sterile distilled water and air-dried. The seeds were coated with formulated B. subtilis BR23 and used for several experiments, such as evaluation for their germination and growth in the laboratory, effectively on R. solani in the baked and nonbaked field soil under greenhouse condition, and in the microplots artificially infested with R. solani. The treatment was compared with other standard seed treatment of synthetic fungicides such as captan (10 g per kg seeds and metalaxyl (10 g per kg seeds. The experiments were designed in a completely random design with three replications. Parameters observed were seed germination, plant height, disease scores, and plant yield. Laboratory formulated B. subtilis BR23 used as seed treatment had no detrimental effects on seed germination and seedling vigor. In microplots artificially infested with a selected highly virulent R. solani, seed treatment with the same formulation increased grain yield by 27% compared to that of the control captan seed treatment with 14.4%. The studies showed the potential of B. subtilis BR23 for commercialization as a seed treatment for the control of banded leaf and sheath blight disease (R. solani in corn.

  2. 21 CFR 173.120 - Carbohydrase and cellulase derived from Aspergillus niger.

    Science.gov (United States)

    2010-04-01

    ... cellulase derived from Aspergillus niger. Carbohydrase and cellulase enzyme preparation derived from Aspergillus niger may be safely used in food in accordance with the following prescribed conditions: (a) Aspergillus niger is classified as follows: Class, Deuteromycetes; order, Moniliales; family, Moniliaceae...

  3. Significance and occurrence of fumonisins from Aspergillus niger

    DEFF Research Database (Denmark)

    Mogensen, Jesper Mølgaard

    Fumonisins is a well-studied group of mycotoxins, mainly produced in maize by Fusarium species. However with the recent discovery of a fumonisin production by Aspergillus niger, other food commodities are at risk, since A. niger is a ubiquitous contaminant of many food and feed products....... The objective of this thesis was to determine the significance and occurrence of fumonisins from Aspergillus niger in food, the frequency of fumonisin production in A. niger isolates, as well as studies of the effect of physiological factors affecting fumonisin production. Major findings in this context have...... been the ocumentation of the production of fumonisins in raisins and peanuts, and occurrence of A. niger derived fumonisins in retail wine and raisins. Physiological investigations have demonstrated that fumonisin production in A. niger occurs at temperatures between 20-37 °C. Three water activity...

  4. Aspergillus Niger Genomics: Past, Present and into the Future

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Scott E.

    2006-09-01

    Aspergillus niger is a filamentous ascomycete fungus that is ubiquitous in the environment and has been implicated in opportunistic infections of humans. In addition to its role as an opportunistic human pathogen, A. niger is economically important as a fermentation organism used for the production of citric acid. Industrial citric acid production by A. niger represents one of the most efficient, highest yield bioprocesses in use currently by industry. The genome size of A. niger is estimated to be between 35.5 and 38.5 megabases (Mb) divided among eight chromosomes/linkage groups that vary in size from 3.5 - 6.6 Mb. Currently, there are three independent A. niger genome projects, an indication of the economic importance of this organism. The rich amount of data resulting from these multiple A. niger genome sequences will be used for basic and applied research programs applicable to fermentation process development, morphology and pathogenicity.

  5. New var reconstruction algorithm exposes high var sequence diversity in a single geographic location in Mali.

    Science.gov (United States)

    Dara, Antoine; Drábek, Elliott F; Travassos, Mark A; Moser, Kara A; Delcher, Arthur L; Su, Qi; Hostelley, Timothy; Coulibaly, Drissa; Daou, Modibo; Dembele, Ahmadou; Diarra, Issa; Kone, Abdoulaye K; Kouriba, Bourema; Laurens, Matthew B; Niangaly, Amadou; Traore, Karim; Tolo, Youssouf; Fraser, Claire M; Thera, Mahamadou A; Djimde, Abdoulaye A; Doumbo, Ogobara K; Plowe, Christopher V; Silva, Joana C

    2017-03-28

    Encoded by the var gene family, highly variable Plasmodium falciparum erythrocyte membrane protein-1 (PfEMP1) proteins mediate tissue-specific cytoadherence of infected erythrocytes, resulting in immune evasion and severe malaria disease. Sequencing and assembling the 40-60 var gene complement for individual infections has been notoriously difficult, impeding molecular epidemiological studies and the assessment of particular var elements as subunit vaccine candidates. We developed and validated a novel algorithm, Exon-Targeted Hybrid Assembly (ETHA), to perform targeted assembly of var gene sequences, based on a combination of Pacific Biosciences and Illumina data. Using ETHA, we characterized the repertoire of var genes in 12 samples from uncomplicated malaria infections in children from a single Malian village and showed them to be as genetically diverse as vars from isolates from around the globe. The gene var2csa, a member of the var family associated with placental malaria pathogenesis, was present in each genome, as were vars previously associated with severe malaria. ETHA, a tool to discover novel var sequences from clinical samples, will aid the understanding of malaria pathogenesis and inform the design of malaria vaccines based on PfEMP1. ETHA is available at: https://sourceforge.net/projects/etha/ .

  6. arXiv Observation of the $\\varXi^{-}_{b}\\to J/\\psi\\varLambda K^{-}$ decay

    CERN Document Server

    Aaij, Roel; Adinolfi, Marco; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Andreassi, Guido; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Archilli, Flavio; d'Argent, Philippe; Arnau Romeu, Joan; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Babuschkin, Igor; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baker, Sophie; Balagura, Vladislav; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Baryshnikov, Fedor; Baszczyk, Mateusz; Batozskaya, Varvara; Batsukh, Baasansuren; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Bel, Lennaert; Bellee, Violaine; Belloli, Nicoletta; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Berezhnoy, Alexander; Bernet, Roland; Bertolin, Alessandro; Betancourt, Christopher; Betti, Federico; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bezshyiko, Iaroslava; Bifani, Simone; Billoir, Pierre; Bird, Thomas; Birnkraut, Alex; Bitadze, Alexander; Bizzeti, Andrea; Blake, Thomas; Blanc, Frederic; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Boettcher, Thomas; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Bordyuzhin, Igor; Borgheresi, Alessio; Borghi, Silvia; Borisyak, Maxim; Borsato, Martino; Bossu, Francesco; Boubdir, Meriem; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Braun, Svende; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Buchanan, Emma; Burr, Christopher; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Camboni, Alessandro; Campana, Pierluigi; Campora Perez, Daniel Hugo; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carniti, Paolo; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cavallero, Giovanni; Cenci, Riccardo; Chamont, David; Charles, Matthew; Charpentier, Philippe; Chatzikonstantinidis, Georgios; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chobanova, Veronika; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombs, George; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Costa Sobral, Cayo Mar; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Da Cunha Marinho, Franciole; Dall'Occo, Elena; Dalseno, Jeremy; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Serio, Marilisa; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Demmer, Moritz; Dendek, Adam; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Dijkstra, Hans; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dovbnya, Anatoliy; Dreimanis, Karlis; Dufour, Laurent; Dujany, Giulio; Dungs, Kevin; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Déléage, Nicolas; Easo, Sajan; Ebert, Marcus; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Farley, Nathanael; Farry, Stephen; Fay, Robert; Fazzini, Davide; Ferguson, Dianne; Fernandez Prieto, Antonio; Ferrari, Fabio; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fini, Rosa Anna; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fleuret, Frederic; Fohl, Klaus; Fontana, Marianna; Fontanelli, Flavio; Forshaw, Dean Charles; Forty, Roger; Franco Lima, Vinicius; Frank, Markus; Frei, Christoph; Fu, Jinlin; Funk, Wolfgang; Furfaro, Emiliano; Färber, Christian; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; Garcia Martin, Luis Miguel; García Pardiñas, Julián; Garra Tico, Jordi; Garrido, Lluis; Garsed, Philip John; Gascon, David; Gaspar, Clara; Gavardi, Laura; Gazzoni, Giulio; Gerick, David; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianì, Sebastiana; Gibson, Valerie; Girard, Olivier Göran; Giubega, Lavinia-Helena; Gizdov, Konstantin; Gligorov, Vladimir; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gorelov, Igor Vladimirovich; Gotti, Claudio; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Griffith, Peter; Grillo, Lucia; Gruberg Cazon, Barak Raimond; Grünberg, Oliver; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Göbel, Carla; Hadavizadeh, Thomas; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hamilton, Brian; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; Hatch, Mark; He, Jibo; Head, Timothy; Heister, Arno; Hennessy, Karol; Henrard, Pierre; Henry, Louis; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hombach, Christoph; Hopchev, P H; Hulsbergen, Wouter; Humair, Thibaud; Hushchyn, Mikhail; Hutchcroft, David; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jawahery, Abolhassan; Jiang, Feng; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Karacson, Matthias; Kariuki, James Mwangi; Karodia, Sarah; Kecke, Matthieu; Kelsey, Matthew; Kenzie, Matthew; Ketel, Tjeerd; Khairullin, Egor; Khanji, Basem; Khurewathanakul, Chitsanu; Kirn, Thomas; Klaver, Suzanne; Klimaszewski, Konrad; Koliiev, Serhii; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Kosmyntseva, Alena; Kozachuk, Anastasiia; Kozeiha, Mohamad; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krokovny, Pavel; Kruse, Florian; Krzemien, Wojciech; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kuonen, Axel Kevin; Kurek, Krzysztof; Kvaratskheliya, Tengiz; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lanfranchi, Gaia; Langenbruch, Christoph; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Leflat, Alexander; Lefrançois, Jacques; Lefèvre, Regis; Lemaitre, Florian; Lemos Cid, Edgar; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Tenglin; Li, Yiming; Likhomanenko, Tatiana; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Xuesong; Loh, David; Longstaff, Iain; Lopes, Jose; Lucchesi, Donatella; Lucio Martinez, Miriam; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Lusiani, Alberto; Lyu, Xiao-Rui; Machefert, Frederic; Maciuc, Florin; Maev, Oleg; Maguire, Kevin; Malde, Sneha; Malinin, Alexander; Maltsev, Timofei; Manca, Giulia; Mancinelli, Giampiero; Manning, Peter Michael; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marinangeli, Matthieu; Marino, Pietro; Marks, Jörg; Martellotti, Giuseppe; Martin, Morgan; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massacrier, Laure Marie; Massafferri, André; Matev, Rosen; Mathad, Abhijit; Mathe, Zoltan; Matteuzzi, Clara; Mauri, Andrea; Maurice, Emilie; Maurin, Brice; Mazurov, Alexander; McCann, Michael; McNab, Andrew; McNulty, Ronan; Meadows, Brian; Meier, Frank; Meissner, Marco; Melnychuk, Dmytro; Merk, Marcel; Merli, Andrea; Michielin, Emanuele; Milanes, Diego Alejandro; Minard, Marie-Noelle; Mitzel, Dominik Stefan; Mogini, Andrea; Molina Rodriguez, Josue; Monroy, Ignacio Alberto; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Morgunova, Olga; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Mulder, Mick; Mussini, Manuel; Müller, Dominik; Müller, Janine; Müller, Katharina; Müller, Vanessa; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nandi, Anita; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Thi Dung; Nguyen-Mau, Chung; Nieswand, Simon; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Nogay, Alla; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Ogilvy, Stephen; Oldeman, Rudolf; Onderwater, Gerco; Otalora Goicochea, Juan Martin; Otto, Adam; Owen, Patrick; Oyanguren, Maria Aranzazu; Pais, Preema Rennee; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parker, William; Parkes, Christopher; Passaleva, Giovanni; Pastore, Alessandra; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Pescatore, Luca; Petridis, Konstantinos; Petrolini, Alessandro; Petrov, Aleksandr; Petruzzo, Marco; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pikies, Malgorzata; Pinci, Davide; Pistone, Alessandro; Piucci, Alessio; Placinta, Vlad-Mihai; Playfer, Stephen; Plo Casasus, Maximo; Poikela, Tuomas; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Pomery, Gabriela Johanna; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Poslavskii, Stanislav; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Quagliani, Renato; Rachwal, Bartolomiej; Rademacker, Jonas; Rama, Matteo; Ramos Pernas, Miguel; Rangel, Murilo; Raniuk, Iurii; Ratnikov, Fedor; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; dos Reis, Alberto; Remon Alepuz, Clara; Renaudin, Victor; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vicente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Lopez, Jairo Alexis; Rodriguez Perez, Pablo; Rogozhnikov, Alexey; Roiser, Stefan; Rollings, Alexandra Paige; Romanovskiy, Vladimir; Romero Vidal, Antonio; Ronayne, John William; Rotondo, Marcello; Rudolph, Matthew Scott; Ruf, Thomas; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sadykhov, Elnur; Sagidova, Naylya; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santimaria, Marco; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schael, Stefan; Schellenberg, Margarete; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmelzer, Timon; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schubert, Konstantin; Schubiger, Maxime; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sergi, Antonino; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Siddi, Benedetto Gianluca; Silva Coutinho, Rafael; Silva de Oliveira, Luiz Gustavo; Simi, Gabriele; Simone, Saverio; Sirendi, Marek; Skidmore, Nicola; Skwarnicki, Tomasz; Smith, Eluned; Smith, Iwan Thomas; Smith, Jackson; Smith, Mark; Snoek, Hella; Soares Lavra, Lais; Sokoloff, Michael; Soler, Paul; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Stefko, Pavol; Stefkova, Slavorima; Steinkamp, Olaf; Stemmle, Simon; Stenyakin, Oleg; Stevens, Holger; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Syropoulos, Vasileios; Szczekowski, Marek; Szumlak, Tomasz; T'Jampens, Stephane; Tayduganov, Andrey; Tekampe, Tobias; Tellarini, Giulia; Teubert, Frederic; Thomas, Eric; van Tilburg, Jeroen; Tilley, Matthew James; Tisserand, Vincent; Tobin, Mark; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Toriello, Francis; Tournefier, Edwige; Tourneur, Stephane; Trabelsi, Karim; Traill, Murdo; Tran, Minh Tâm; Tresch, Marco; Trisovic, Ana; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tully, Alison; Tuning, Niels; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valassi, Andrea; Valat, Sebastien; Valenti, Giovanni; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vecchi, Stefania; van Veghel, Maarten; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Venkateswaran, Aravindhan; Vernet, Maxime; Vesterinen, Mika; Viana Barbosa, Joao Vitor; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Viemann, Harald; Vilasis-Cardona, Xavier; Vitti, Marcela; Volkov, Vladimir; Vollhardt, Achim; Voneki, Balazs; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Vázquez Sierra, Carlos; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wang, Jianchun; Ward, David; Wark, Heather Mckenzie; Watson, Nigel; Websdale, David; Weiden, Andreas; Whitehead, Mark; Wicht, Jean; Wilkinson, Guy; Wilkinson, Michael; Williams, Mark Richard James; Williams, Matthew; Williams, Mike; Williams, Timothy; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wraight, Kenneth; Wyllie, Kenneth; Xie, Yuehong; Xing, Zhou; Xu, Zhirui; Yang, Zhenwei; Yao, Yuezhe; Yin, Hang; Yu, Jiesheng; Yuan, Xuhao; Yushchenko, Oleg; Zarebski, Kristian Alexander; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Yanxi; Zhang, Yu; Zhelezov, Alexey; Zheng, Yangheng; Zhu, Xianglei; Zhukov, Valery; Zucchelli, Stefano

    2017-09-10

    The observation of the decay $\\varXi_{b}^{-}\\to J/\\psi\\varLambda K^{-}$ is reported, using a data sample corresponding to an integrated luminosity of $3~\\mathrm{fb}^{-1}$, collected by the LHCb detector in $pp$ collisions at centre-of-mass energies of $7$ and $8~\\mathrm{TeV}$. The production rate of $\\varXi_{b}^{-}$ baryons detected in the decay $\\varXi_{b}^{-}\\to J/\\psi\\varLambda K^{-}$ is measured relative to that of $\\varLambda_{b}^{0}$ baryons using the decay $\\varLambda_{b}^{0}\\to J/\\psi \\varLambda$. Integrated over the $b$-baryon transverse momentum $p_{\\rm T}<25~\\mathrm{GeV/}c $ and rapidity $2.0 < y < 4.5$, the measured ratio is \\begin{equation*} \\frac{f_{\\varXi_{b}^{-}}}{f_{\\varLambda_{b}^{0}}}\\frac{\\mathcal{B}(\\varXi_{b}^{-}\\to J/\\psi\\varLambda K^{-})}{\\mathcal{B}(\\varLambda_{b}^{0}\\to J/\\psi \\varLambda)}=(4.19\\pm 0.29~(\\mathrm{stat})\\pm0.14~(\\mathrm{syst}))\\times 10^{-2}, \\end{equation*}where $f_{\\varXi_{b}^{-}}$ and $f_{\\varLambda_{b}^{0}}$ are the fragmentation fractions of $b\\to\\varXi_{...

  7. Aspergillus niger endocarditis in an immunocompetent patient: an unusual course

    Science.gov (United States)

    Kreiss, Y.; Vered, Z.; Keller, N.; Kochva, I.; Sidi, Y.; Gur, H.

    2000-01-01

    Aspergillus is an opportunistic nosocomial fungus generally associated with a high mortality rate. A niger has been rarely associated with infection, and most cases have occurred in patients who have recently undergone heart surgery or in immunocompromised patients. We present a case of an immunocompetent patient with A niger endocarditis which illustrates the difficulties in diagnosis and the possible insidious course of fungal endocarditis.


Keywords: endocarditis; Aspergillus niger; transoesophageal echocardiography PMID:10644391

  8. [New antibiotics produced by Bacillus subtilis strains].

    Science.gov (United States)

    Malanicheva, I A; Kozlov, D G; Efimenko, T A; Zenkova, V A; Kastrukha, G S; Reznikova, M I; Korolev, A M; Borshchevskaia, L N; Tarasova, O D; Sineokiĭ, S P; Efremenkova, O V

    2014-01-01

    Two Bacillus subtilis strains isolated from the fruiting body of a basidiomycete fungus Pholiota squarrosa exhibited a broad range of antibacterial activity, including those against methicillin-resistant Staphylococcus aureus INA 00761 (MRSA) and Leuconostoc mes6nteroides VKPM B-4177 resistant to glycopep-> tide antibiotics, as well as antifungal activity. The strains were identified as belonging to the "B. subtilis" com- plex based on their morphological and physiological characteristics, as well as by sequencing of the 16S rRNA gene fragments. Both strains (INA 01085 and INA 01086) produced insignificant amounts of polyene antibiotics (hexaen and pentaen, respectively). Strain INA 01086 produced also a cyclic polypeptide antibiotic containing Asp, Gly, Leu, Pro, Tyr, Thr, Trp, and Phe, while the antibiotic of strain INA 01085 contained, apart from these, two unidentified nonproteinaceous amino acids. Both polypeptide antibiotics were new compounds efficient against gram-positive bacteria and able to override the natural bacterial antibiotic resistance.

  9. Niger: A State Rich in Uranium

    International Nuclear Information System (INIS)

    Gregoire, Emmanuel

    2011-01-01

    The kidnapping on 16 September 2010 of seven Areva and Satom (a subsidiary of the Vinci Group) employees, which was claimed by the Salafist brigade of Al Qaeda in the Islamic Maghreb (AQIM), thrust the Republic of Niger into the political and media spotlight. This commando-type operation at the Arlit mining site was followed four months later by a similar operation, this time in the heart of Niger's capital, Niamey. While four of the seven hostages are still being held in northern Mali (three were released in February 2011), the two young people abducted from a restaurant in Niamey were probably executed by their captors as they were pursued at the Malian border by the Niger army supported by French troops. [2] According to another version, one of the young people...[2] Among the poorest countries in the world, Niger rarely features in the headlines, except for the dramatic periods of drought which regularly affect the population, leading to solidarity campaigns, and for coups d'etat impacting the country's political life. The most recent of these coups d'etat (February 18, 2010) deposed President Mamadou Tandja who had modified the Constitution in order to remain in power (Gregoire 2010). Since then, the chain of historical events has accelerated at a rapid pace. The latest event was the election of Mahamadou Issoufou as president of the republic, after an election that took place under conditions of transparency and respect for democracy (March 12, 2011). The task facing the ninth Niger president will not be easy. Among other things, he will have to address the insecurity resulting from the presence of AQIM in Mali's territory, which was 'refueled' by western hostages in Niger. He will also need to eradicate the criminal economy (trafficking of all kinds, starting with drugs) now widespread in the Sahara region, and attempt to lift the country out of underdevelopment. The renewed interest shown by the international community in Niger's uranium deposits, and the

  10. Variación ambiental y patrones di etarios del erizo negro Tetrapygus niger en costas intermareales rocosas del norte de Chile Environmental variation and dietary patterns of the black urchin Tetrapygus niger in rocky intertidal shores of northern Chile

    Directory of Open Access Journals (Sweden)

    ARTURO H NAVARRETE

    2008-09-01

    Full Text Available El rol e impacto de los herbívoros en la trama trófica de comunidades intermareales rocosas podría ser más diverso y complejo de lo considerado hasta ahora, particularmente en el caso de consumidores de mayor tamaño y abundancia como el erizo negro Tetrapygus niger (Molina en la costa de Chile. En este contexto, analizamos la variación en riqueza y composición de la dieta de T. niger en cuatro comunidades intermareales rocosas del norte de Chile, distribuidas en 1.000 km de costa, y muestreadas estacionalmente entre invierno 2004 y primavera 2005. Durante el estudio ocurrió el evento El Niño 2004-2005 cuyo efecto potencial fue incorporado en esta evaluación. En cada comunidad y estación se evaluó la abundancia de las especies presentes en 45 cuadrantes (0,25 m² distribuidos en cinco bloques permanentes, recolectando cerca de 10 individuos de T. niger a los que se midió su biomasa y longitud, determinando el número, identidad y frecuencia de ocurrencia de ítemes en su contenido gástrico. Colectamos un total de 251 individuos de T. niger, que en conjunto consumieron 89 ítemes de algas (64 % e invertebrados (36 %; incluyendo otros herbívoros. Una relación inversa significativa entre el tamaño corporal y el número de ítemes animales ingeridos sugiere que T. niger varía su dieta durante la ontogenia. La amplitud de nicho dietario fue alta y tendió a disminuir hacia latitudes menores. Globalmente, el espectro y frecuencia de ocurrencia de ítemes dietarios no fueron significativamente distintos entre comunidades, pese a marcadas diferencias en intensidad de surgencia entre ellas. Similarmente, no hubo relación clara entre la oferta ambiental de recursos y su frecuencia en la dieta de T. niger, destacando la clorófita Ulva rígida que fue el ítem consumido con más frecuencia en cada comunidad pero no el más abundante en terreno. Sin embargo, la riqueza dietaria de T. niger se relacionó negativa y significativamente con la

  11. Development of Bacillus subtilis mutants to produce tryptophan in pigs

    DEFF Research Database (Denmark)

    Bjerre, Karin; Cantor, Mette D.; Nørgaard, Jan Værum

    2017-01-01

    Objectives To generate tryptophan-overproducing Bacillus subtilis strains for in situ use in pigs, to reduce the feed cost for farmers and nitrogen pollution. Results A novel concept has been investigated—to generate B. subtilis strains able to produce tryptophan (Trp) in situ in pigs. Mutagenesis......-excreting B. subtilis strains were obtained with UV-mutagenesis and analogue selection and can be used in animal feed applications....

  12. Logarithmic sensing in Bacillus subtilis aerotaxis.

    Science.gov (United States)

    Menolascina, Filippo; Rusconi, Roberto; Fernandez, Vicente I; Smriga, Steven; Aminzare, Zahra; Sontag, Eduardo D; Stocker, Roman

    2017-01-01

    Aerotaxis, the directed migration along oxygen gradients, allows many microorganisms to locate favorable oxygen concentrations. Despite oxygen's fundamental role for life, even key aspects of aerotaxis remain poorly understood. In Bacillus subtilis, for example, there is conflicting evidence of whether migration occurs to the maximal oxygen concentration available or to an optimal intermediate one, and how aerotaxis can be maintained over a broad range of conditions. Using precisely controlled oxygen gradients in a microfluidic device, spanning the full spectrum of conditions from quasi-anoxic to oxic (60 n mol/l-1 m mol/l), we resolved B. subtilis' 'oxygen preference conundrum' by demonstrating consistent migration towards maximum oxygen concentrations ('monotonic aerotaxis'). Surprisingly, the strength of aerotaxis was largely unchanged over three decades in oxygen concentration (131 n mol/l-196 μ mol/l). We discovered that in this range B. subtilis responds to the logarithm of the oxygen concentration gradient, a rescaling strategy called 'log-sensing' that affords organisms high sensitivity over a wide range of conditions. In these experiments, high-throughput single-cell imaging yielded the best signal-to-noise ratio of any microbial taxis study to date, enabling the robust identification of the first mathematical model for aerotaxis among a broad class of alternative models. The model passed the stringent test of predicting the transient aerotactic response despite being developed on steady-state data, and quantitatively captures both monotonic aerotaxis and log-sensing. Taken together, these results shed new light on the oxygen-seeking capabilities of B. subtilis and provide a blueprint for the quantitative investigation of the many other forms of microbial taxis.

  13. [Hygiene, safety and occupational medicine in Niger].

    Science.gov (United States)

    Moussa, F; Sékou, H

    1997-01-01

    The laws and rules governing hygiene, safety and medicine in the workplace in Niger were evaluated in this study. We used labour administration, health service and Social Security Department reports to review each type of professional activity and the risks associated with it. This enabled us to make recommendations to the authorities and to the organizations representing employers and staff, concerning the prevention of risks at work.

  14. Biosorption of uranium with Aspergillus niger

    International Nuclear Information System (INIS)

    Yakubu, N.A.; Dudeney, A.W.L.

    1986-01-01

    This paper considers interactions of uranium with the microfilamentous fungus Aspergillus niger grown as pellets 4 mm in diameter for column application. Adsorption and desorption isotherms, a range of physical measurements, and a derived mechanistic model, indicated that a simple ion exchange process predominates in which uranyl cations reversibly replace protons on the amino acid groups of proteins and glycoproteins within the cell wall structure. Under the conditions employed uranium adsorbed onto A. niger (CMI 296409) some fourteen times more efficiently at pH 4 than onto the ion exchange resin IRA-400, and was readily desorbed at pH 1. The fungus had inferior selectivity and wet volume/dry weight ratio. Uranium was adsorbed semi-continuously by heat-killed A. niger pellets fluidised in a compartmentalised column. When operated with an intermittent countercurrent flow of the biomass, uranium concentrations of 100 g/m 3 and 5 g/m 3 at pH 4 could be reduced to less than 10 g/m 3 and 1 g/m 3 , respectively. (author)

  15. Antifungal, Mechanical, and Physical Properties of Edible Film Containing Williopsis saturnus var. saturnus Antagonistic Yeast.

    Science.gov (United States)

    Karabulut, Gulsah; Cagri-Mehmetoglu, Arzu

    2018-03-01

    The molding of food products causing health risks is a main problem in the food industry. In this study, as an alternative solution for preventing mold growth, an antifungal edible film was developed by incorporating Williopsis saturnus var. saturnus (0; 3; 7; and 9 logs CFU/cm 2 ) into whey protein concentrate (WPC) based films. Antifungal properties of the films against Penicilium expansum and Aspergillus niger were analyzed using the disc diffusion method. Physical (barrier, solubility, color), mechanical (tensile strength and percent elongation) properties of the films as well as the survival of W. saturnus in the film were assessed during 28 days of storage at 23 °C. According to the results, the viability of W. saturnus (7 and 9 logs CFU/cm 2 ) in WPC films stored for 28 days under vacuum or non-vacuum decreased to 36% and 60%, respectively. In addition, films containing W. saturnus decreased the viability of P. expansum and A. niger by 29% and 19%, respectively. Adding yeast did not change the tensile strength (P > 0.05), but significantly decreased % elongation and increased water vapor and oxygen permeability and water solubility (P films may be useful for inhibiting mold growth on foods. © 2018 Institute of Food Technologists®.

  16. Polycistronic gene expression in Aspergillus niger.

    Science.gov (United States)

    Schuetze, Tabea; Meyer, Vera

    2017-09-25

    Genome mining approaches predict dozens of biosynthetic gene clusters in each of the filamentous fungal genomes sequenced so far. However, the majority of these gene clusters still remain cryptic because they are not expressed in their natural host. Simultaneous expression of all genes belonging to a biosynthetic pathway in a heterologous host is one approach to activate biosynthetic gene clusters and to screen the metabolites produced for bioactivities. Polycistronic expression of all pathway genes under control of a single and tunable promoter would be the method of choice, as this does not only simplify cloning procedures, but also offers control on timing and strength of expression. However, polycistronic gene expression is a feature not commonly found in eukaryotic host systems, such as Aspergillus niger. In this study, we tested the suitability of the viral P2A peptide for co-expression of three genes in A. niger. Two genes descend from Fusarium oxysporum and are essential to produce the secondary metabolite enniatin (esyn1, ekivR). The third gene (luc) encodes the reporter luciferase which was included to study position effects. Expression of the polycistronic gene cassette was put under control of the Tet-On system to ensure tunable gene expression in A. niger. In total, three polycistronic expression cassettes which differed in the position of luc were constructed and targeted to the pyrG locus in A. niger. This allowed direct comparison of the luciferase activity based on the position of the luciferase gene. Doxycycline-mediated induction of the Tet-On expression cassettes resulted in the production of one long polycistronic mRNA as proven by Northern analyses, and ensured comparable production of enniatin in all three strains. Notably, gene position within the polycistronic expression cassette matters, as, luciferase activity was lowest at position one and had a comparable activity at positions two and three. The P2A peptide can be used to express at

  17. Taxonomical studies on endemic scorzonera pygmaea var. pygmaea and var. nutans stat. nov. (asteraceae) from turkey

    International Nuclear Information System (INIS)

    Koyuncu, O.; Kus, G.

    2014-01-01

    The taxonomic status of Scorzonera pygmaea var. pygmaea and var. nutans belonging to the tribe. cichoreae (Asteraceae). S. pygmaea samples were collected from Arayit mountain. We suggest that these two subspecies should be classified as varietes because of their morphological and anatomical characteristics, ecological and geographical similarities. Moreover being together in the same localities of these under species taxa supports our opinion, i.e. S. pygmaea Sibth. and Sm. var. pygmaea stat. nov. and S. pygmaea Sibth. and Sm. var. nutans (Czeczott) O. Koyuncu and Yaylac, stat. nov. (author)

  18. Antimicrobial gageomacrolactins characterized from the fermentation of the marine-derived bacterium Bacillus subtilis under optimum growth conditions.

    Science.gov (United States)

    Tareq, Fakir Shahidullah; Kim, Ji Hye; Lee, Min Ah; Lee, Hyi-Seung; Lee, Jong-Seok; Lee, Yeon-Ju; Shin, Hee Jae

    2013-04-10

    Marine bacteria are a potential source of structurally diversified bioactive secondary metabolites that are not found in terrestrial sources. In our continuous effort to search for new antimicrobial agents from marine-derived bacteria, we isolated bacterial strain 109GGC020 from a marine sediment sample collected from Gageocho, Republic of Korea. The strain was identified as Bacillus subtilis based on a 16s rRNA sequence analysis. After a 7-day fermentation of the B. subtilis strain under optimum growth conditions three new and four known secondary metabolites were discovered using chromatographic procedures, and their biological activities were evaluated against both bacteria and crop-devastating fungi. The discovered metabolites were confirmed by extensive 2D NMR and high-resolution ESI-MS data analyses to have the structures of new macrolactin derivatives gageomacrolactins 1-3 and known macrolactins A (4), B (5), F (6), and W (7). The stereoconfigurations of 1-3 were assigned based on coupling constant values, chemical derivatization studies, and a literature review. The coupling constants were very crucial to determine the relative geometries of olefins in 1-3 because of overlap of the ¹H NMR signals. The NMR data of these compounds were recorded in different solvents to overcome this problem and obtain accurate coupling constant values. The new macrolactin derivatives 1-3 displayed good antibiotic properties against both Gram-positive (S. aureus, B. subtilis, and B. cereus) and Gram-negative (E. coli, S. typhi, and P. aeruginosa) bacteria with minimum inhibitory concentration (MIC) values of 0.02-0.05 μM. Additionally, the antifungal activities of 1-7 were evaluated against pathogenic fungi and found to inhibit mycelial growth of A. niger, B. cinerea, C. acutatum, C. albicans, and R. solani with MIC values of 0.04-0.3 μM, demonstrating that these compounds were good fungicides.

  19. "Var Teatre"--A Pioneer Turns 40.

    Science.gov (United States)

    Jones, Pamela L.

    1984-01-01

    Describes the Stockholm Municipal Youth and Children's theatre ("Var Teatre"), an institution of 14 theatres and attendant professional staff devoted exclusively to drama activities for children and teenagers. (PD)

  20. 4D-Var Developement at GMAO

    Science.gov (United States)

    Pelc, Joanna S.; Todling, Ricardo; Akkraoui, Amal El

    2014-01-01

    The Global Modeling and Assimilation Offce (GMAO) is currently using an IAU-based 3D-Var data assimilation system. GMAO has been experimenting with a 3D-Var-hybrid version of its data assimilation system (DAS) for over a year now, which will soon become operational and it will rapidly progress toward a 4D-EnVar. Concurrently, the machinery to exercise traditional 4DVar is in place and it is desirable to have a comparison of the traditional 4D approach with the other available options, and evaluate their performance in the Goddard Earth Observing System (GEOS) DAS. This work will also explore the possibility for constructing a reduced order model (ROM) to make traditional 4D-Var computationally attractive for increasing model resolutions. Part of the research on ROM will be to search for a suitably acceptable space to carry on the corresponding reduction. This poster illustrates how the IAU-based 4D-Var assimilation compares with our currently used IAU-based 3D-Var.

  1. Niger Delta Crisis and Security Implications for the Nation State ...

    African Journals Online (AJOL)

    The Niger Delta is the nation's treasure base, the Niger Delta provides over 80 percent of government revenue, 95 percent of export receipts, and 90 percent of ... The government should tackle the fundamental issue of basic necessities – provision of good motorable roads, pipe borne water, electricity, good hospitals, good ...

  2. Aspergillus niger Secretes Citrate to Increase Iron Bioavailability

    Science.gov (United States)

    Odoni, Dorett I.; van Gaal, Merlijn P.; Schonewille, Tom; Tamayo-Ramos, Juan A.; Martins dos Santos, Vitor A. P.; Suarez-Diez, Maria; Schaap, Peter J.

    2017-01-01

    Aspergillus niger has an innate ability to secrete various organic acids, including citrate. The conditions required for A. niger citrate overproduction are well described, but the physiological reasons underlying extracellular citrate accumulation are not yet fully understood. One of the less understood culture conditions is the requirement of growth-limiting iron concentrations. While this has been attributed to iron-dependent citrate metabolizing enzymes, this straightforward relationship does not always hold true. Here, we show that an increase in citrate secretion under iron limited conditions is a physiological response consistent with a role of citrate as A. niger iron siderophore. We found that A. niger citrate secretion increases with decreasing amounts of iron added to the culture medium and, in contrast to previous findings, this response is independent of the nitrogen source. Differential transcriptomics analyses of the two A. niger mutants NW305 (gluconate non-producer) and NW186 (gluconate and oxalate non-producer) revealed up-regulation of the citrate biosynthesis gene citA under iron limited conditions compared to iron replete conditions. In addition, we show that A. niger can utilize Fe(III) citrate as iron source. Finally, we discuss our findings in the general context of the pH-dependency of A. niger organic acid production, offering an explanation, besides competition, for why A. niger organic acid production is a sequential process influenced by the external pH of the culture medium. PMID:28824560

  3. Conflict resolution among Niger delta communities: A historical ...

    African Journals Online (AJOL)

    Conflict related issues have assumed endemic proportion in the Niger Delta. A proper assessment of the critical factors in motion must take cognizance of their historical underpinnings. Peaceful co-existence, the hallmark of conflict resolution, can be feasible in the Niger Delta, through sustainable dialogue. These, among

  4. Caribbean piracy and youth restiveness in Niger delta: A ...

    African Journals Online (AJOL)

    Our aim in this paper is to make a comparative analysis of Caribbean piracy and youth restiveness in Niger Delta of Nigeria. It will not be out of place to carry out such an analysis having seen, heard or read of the ongoing chaos, insecurity in the. Niger Delta Zone in Nigeria. We have to look at the past to find out such similar

  5. Organic acid production in Aspergillus niger and other filamentous fungi

    NARCIS (Netherlands)

    Odoni, Dorett I.

    2017-01-01

    The aim of the thesis was to increase the understanding of organic acid production in Aspergillus niger and other filamentous fungi, with the ultimate purpose to improve A. niger as biotechnological production host.

    In Chapter 1, the use of microbial

  6. Estimation of Thermal Conductivity in the North- Western Niger Delta ...

    African Journals Online (AJOL)

    Thermal conductivity estimates are computed from nineteen petroleum wells in the north-western Niger Delta, Nigeria, using a geometric mean model. Sonic and gamma-ray logs were digitised and used in the estimation of in situ conductivity. The Niger Delta is composed of three major diachronous lithostratigraphic units of ...

  7. Corn stover-enhanced cellulase production by Aspergillus niger ...

    African Journals Online (AJOL)

    The production of extracellular cellulases by Aspergilus niger NRRL 567 on corn stover was studied in liquid state fermentation. In this study, three cellulases, exoglucanase (EXG), endoglucanase (EG) and β-glucosidase (BGL) were produced by A. niger NRRL 567. The optimal pH, temperature and incubation time for ...

  8. Dousing the tension in the Niger delta through administrative agency

    African Journals Online (AJOL)

    Dousing the tension in the Niger delta through administrative agency: A programme evaluation of Niger delta development commission as an intervention regime. ... the study concludes that because of systemic constraints arising from the hegemonic interests of the dominant coalitions in the Nigerian Social formation, ...

  9. Expression of human lymphotoxin alpha in Aspergillus niger

    NARCIS (Netherlands)

    Krasevec, N.; Hondel, C.A.M.J.J. van de; Komel, R.

    2000-01-01

    A gene-fusion expression strategy was applied for heterologous expression of human lymphotoxin alpha (LTα) in the Aspergillus niger AB1.13 protease-deficient strain. The LTα gene was fused with the A. niger glucoamylase GII-form as a carrier-gene, behind its transcription control and secretion

  10. screening and improvement of local isolates of aspergillus niger

    African Journals Online (AJOL)

    DR. AMINU

    ABSTRACT. The study involved the screening of fourteen isolates of Aspergillus niger for citric acid production from glucose. The study was aimed at screening and improving local strains of Aspergillus niger with potential for citric acid production. All the isolates screened produced varying amounts of citric acid, the highest ...

  11. Partially purified polygalacturonase from Aspergillus niger (SA6 ...

    African Journals Online (AJOL)

    Polygalacturonase (PG) was isolated from Aspergillus niger (A. niger) (SA6), partially purified and characterized. The PG showed two bands on SDS-PAGE suggesting an “endo and exo PG with apparent molecular weights of 35 and 40 KDa, respectively. It was purified 9-fold with a yield of 0.18% and specific activity of 246 ...

  12. A novel pig feed formulation containing Aspergillus niger CSA35 ...

    African Journals Online (AJOL)

    This study investigated the effects of Aspergillus niger CSA35 pretreated-cassava (Manihot esculenta Crantz) peel feed (CPFG) on the body weight gain and some selected biochemical parameters of pigs. Cassava peels treated with biomass of A. niger CSA35 for a period of three weeks to initiate enzymatic digestion of ...

  13. Homosexuality amongst migrant oil workers in the Niger Delta ...

    African Journals Online (AJOL)

    Aims: To determine the prevalence of homosexuality among migrant oil workers in Niger Delta. Methods: A prospective questionnaire – based study was conducted among migrant oil workers in the Niger Delta region of Nigeria. The design was to determine the prevalence of homosexuality in the workers in oil workers.

  14. Complete Genome Sequence of Bacillus subtilis subsp. subtilis Strain ∆6

    NARCIS (Netherlands)

    Reuß, Daniel R; Thürmer, Andrea; Daniel, Rolf; Quax, Wim J; Stülke, Jörg

    2016-01-01

    Bacillus subtilis ∆6 is a genome-reduced strain that was cured from six prophages and AT-rich islands. This strain is of great interest for biotechnological applications. Here, we announce the full-genome sequence of this strain. Interestingly, the conjugative element ICEBs1 has most likely

  15. Biodegradation of naphthalene and phenanthren by Bacillus subtilis 3KP

    Science.gov (United States)

    Ni'matuzahroh, Trikurniadewi, N.; Pramadita, A. R. A.; Pratiwi, I. A.; Salamun, Fatimah, Sumarsih, Sri

    2017-06-01

    The purposes of this research were to know growth response, degradation ability, and uptake mechanism of naphthalene and phenanthrene by Bacillus subtilis 3KP. Bacillus subtilis 3KP was grown on Mineral Synthetic (MS) medium with addition of 1% yeast extract and naphthalene and phenanthrene respectively 200 ppm in different cultures. Bacillus subtilis 3KP growth response was monitored by Total Plate Count (TPC) method, the degradation ability was monitored by UV-Vis spectrophotometer, and the uptake mechanism of hydrocarbon was monitored by emulsification activity, decrease of surface tension, and activity of Bacterial Adherence to Hydrocarbon (BATH). Bacillus subtilis 3KP was able to grow and show biphasic growth pattern on both of substrates. Naphthalene and phenanthrene were used as a carbon source for Bacillus subtilis 3KP growth that indicated by the reduction of substrate concomitant with the growth. At room temperature conditions (± 30°C) and 90 rpm of agitation for 7 days, Bacillus subtilis 3KP could degrade naphthalene in the amount of 70.5% and phenanthrene in the amount of 24.8%. Based on the analysis of UV-Vis spectrophotometer, three metabolites, 1-hydroxy-2-naphthoic acid, salicylic acid, and pyrocatechol were found in both cultures. The metabolite identification became basis of propose degradation pathway of naphthalene and phenanthrene by Bacillus subtilis 3KP. The results of hydrocarbon uptake mechanism test show that Bacillus subtilis 3KP used all of the mechanism to degrade naphthalene and phenanthrene.

  16. Bacillus subtilis Hfq: A role in chemotaxis and motility

    Indian Academy of Sciences (India)

    2016-07-16

    Jul 16, 2016 ... motility, thus assigning a new function for Hfq in B. subtilis. 1. Introduction. Hfq in ... to play a role in pathogenecity in mice, tolerance to osmotic and ethanol stress ...... in B. subtilis is characterized by events like surfactin pro- duction .... SM Cutting (New York: John Wiley and Sons Inc) pp 442–444. Nicolas P ...

  17. Effect of Bacillus subtilis on Granite Weathering: A Laboratory Experiment

    Science.gov (United States)

    Song, W.; Ogawa, N.; Oguchi, C. T.; Hatta, T.; Matsukura, Y.

    2006-12-01

    We performed a comparative experiment to investigate how the ubiquitous soil bacterium Bacillus subtilis weathers granite and which granite-forming minerals weather more rapidly via biological processes. Batch type experiments (granite specimen in a 500 ml solution including NaCl, glucose, yeast extract and bacteria Bacillus subtilis at 27°E C) were carried out for 30 days. Granite surfaces were observed by SEM before and after the experiment. Bacillus subtilis had a strong influence on granite weathering by forming pits. There were 2.4 times as many pits and micropores were 2.3 times wider in granite exposed to Bacillus subtilis when compared with bacteria-free samples. Bacillus subtilis appear to preferentially select an optimum place to adhere to the mineral and dissolve essential elements from the mineral to live. Plagioclase was more vulnerable to bacterial weathering than biotite among the granite composing minerals.

  18. Engineering of Bacillus subtilis 168 for increased nisin resistance

    DEFF Research Database (Denmark)

    Hansen, Mette; Wangari, Romilda; Hansen, Egon Bech

    2009-01-01

    . Bacillus subtilis had been suggested as a potential host for the biosynthesis of nisin but was discarded due to its sensitivity to the lethal action of nisin. In this study, we have reevaluated the potential of B. subtilis as a host organism for the heterologous production of nisin. We applied...... transcriptome and proteome analyses of B. subtilis and identified eight genes upregulated in the presence of nisin. We demonstrated that the overexpression of some of these genes boosts the natural defenses of B. subtilis, which allows it to sustain higher levels of nisin in the medium. We also attempted...... to overcome the nisin sensitivity of B. subtilis by introducing the nisin resistance genes nisFEG and nisI from L. lactis under the control of a synthetic promoter library....

  19. Exploration and uranium mining in Niger

    International Nuclear Information System (INIS)

    Moussa, M.

    2014-01-01

    Niger is a Sahelian country bordered by Algeria and Libya to the north, Mali and Burkina Faso to the west, Benin and Nigeria to the south and Chad to the east. Niger has approximately 17 million habitants in the last census (2013) and covers an area of 1.27 million km"2. Niger’s climate is very hot and dry (45-50°C in the hot season, 30°C in the winter), daily ranges of temperature vary from 20 to 30°C. There is a rainy season with light rain fall (40 mm) extending from June to September. Niger’s economy is centered on subsistence agriculture, animal husbandry and uranium production. Uranium exports accounted for 70% of the national export economy during the 1970s, but falling prices have caused the contribution from uranium to shrink substantially in recent years. Uranium ore deposits in the Niger Republic are located in the western part of the country, west of the Aïr Mountains. The Arlit site is located 250 km north of Agadez, and 1200 km north-west of Niamey, the capital of Niger. After the discovery of the first uranium occurrences in 1956, systematic exploration programmes were conducted between 1960 and 1968 along the western sedimentary margin of Aïr Mountains, in North Central Niger by French company CEA. These programmes led to the discovery of several uranium deposits including the Arlit and Akouta deposits which are presently being mined respectively by SOMAIR and Cominak. Further works by CEA and its 100% subsidiary COGEMA and other companies consisted basically in follow up of the different targets outlined by the above programmes. The rocks hosting the uranium mineralisation are commonly arenites of the Carboniferous age Guezouman and Tarat Formations. Some beds within the Tchirozerine Formation of Jurassic age and the Irhazer Formation of Cretaceous age also contain uranium. The depositional environment of these formations was fluvial to deltaic. Apparently uranium was leached from the basement. Tectonic, lithological and geochemical

  20. Weinig VVT-instellingen met VAR : onderzoek naar VAR's in Nederland

    NARCIS (Netherlands)

    Corina de Feijter; Pieterbas Lalleman

    V&VN is op zoek gegaan naar alle actieve Verpleegkundige en/of Verzorgende Adviesraden (VAR) in Nederland. Het blijkt dat in totaal 144 zorginstellingen (24%) een VAR hebben. Vooral in de VVT-sector is het aantal VAR’s laag: 13%.

  1. Molecular and physiological diversity among Verticillium fungicola var. fungicola and var. aleophilum

    NARCIS (Netherlands)

    Largeteau, M.L.; Baars, J.J.P.; Savoie, J.M.

    2006-01-01

    The genetic and physiological variability of Verticillium fungicola var. aleophilum responsible for Agaricus bisporus dry bubble disease in North America is well documented but little is known about the var. fungicola affecting European crops. Variability was assessed within this variety and

  2. Over de verspreiding binnen Nederland van Bidens connata var. fallax (Warnst.) Sherf en var. anomala Farw

    NARCIS (Netherlands)

    Ballintijn, Koos (J.) F.

    1997-01-01

    On the basis of recent observations and study of herbarium material it might tentatively be concluded that var. anomala (with erecto-patent barb hairs on achenes as well as on the bristles) is becoming more common since 1954 and might be locally replacing the hitherto more common var. fallax (with

  3. Antimicrobial activity and essential oil composition of a new T. argyrophyllum (C. Koch) Tvzel var. argyrophyllum chemotype.

    Science.gov (United States)

    Polatoglu, Kaan; Demirci, Fatih; Demirci, Betül; Gören, Nezhun; Can Baser, Kemal Hüsnü

    2010-01-01

    Water-distilled essential oils from flowers and stems of Tanacetum argyrophyllum var. argyrophyllum from Turkey were analyzed by GC and GC/MS. The flower oil of T. argyrophyllum var. argyrophyllum was characterized with camphor 29.7%, borneol 12.0%, 1,8-cineole 8.4% and bornyl acetate 6.1%. Stem oil was characterized with camphor 26.6%, 1,8-cineole 17.5%, and borneol 15.0%. Our previous research and literature on the essential oil of this plant reported oils with high thujone content unlike the present study. Antibacterial activity of the oils were evaluated for five Gram-positive and five Gram-negative bacteria by using a broth microdilution assay. The highest inhibitory activity was observed against Bacillus cereus for stem oil (125 microg/mL) when compared with positive control chloramphenicol it showed the same inhibition potency. However, the same oil showed lower inhibitory activity against B. subtilis. The flower oil did not show significant activity against the tested microorganisms. DPPH radical scavenging activity of the T. argyrophyllum var. argyrophyllum oil was investigated at 15 and 10 mg/mL concentrations. However, the oils did not show any significant activity when compared to positive control alpha-tocopherol. Both of the oils showed toxicity to Vibrio fischeri in the TLC-bioluminescence assay.

  4. Retting of Flax by Aspergillus niger

    Science.gov (United States)

    De França, F. P.; Rosemberg, J. A.; De Jesus, A. M.

    1969-01-01

    In this study, retting was carried out by Aspergillus niger. The pH, galacturonic acid (GA), and total reducing sugar were determined; the end point was identified by the classic empirical processes and by the maximal GA content of the retting water. The process gave clear and resistent fibers, and the retting time was similar to that of current industrial processes with bacterial enzymes. Control of total acidity was not required, since the pH remained close to neutrality throughout the entire process. PMID:16349835

  5. The situation in the Niger Delta

    International Nuclear Information System (INIS)

    Vitalis, E.

    2007-01-01

    An energy issue for the United States and a political challenge for Europe, Nigeria is experiencing growing instability and is on the verge of civil war; the ecosystem and the population of the Niger Delta are the main victims. The State, corrupt, is powerless to contain the rising violence and redistribute the proceeds of oil sales. It is high time for oil-consuming countries, starting with the United States, to concern themselves with stabilizing the region. Europe must contribute to the lasting development of this country. (author)

  6. Peptides derived from tryptic hydrolysate of Bacillus subtilis culture suppress fungal spoilage of table grapes.

    Science.gov (United States)

    Zhang, Bo; Wang, Jingnan; Ning, Shuqing; Yuan, Quan; Chen, Xiangning; Zhang, Yanyan; Fan, Junfeng

    2018-01-15

    This study confirmed the anti-fungal effect of trypsin-treated Bacillus subtilis culture (BC) (tryptic hydrolysate, TH) on mold growth on Kyoho grapes. We examined the anti-fungal activity of TH by identifying TH peptides and performing a computational docking analysis. TH was more potent than untreated BC in suppressing fungal growth on grapes. Specifically, TH maintained grape freshness by inhibiting respiration and rachis browning, maintaining firmness, and preventing weight loss. Thirty-six inhibitory peptides against β-1,3-glucan synthase (GS) were screened from 126 TH peptides identified through proteomic analysis. Among them, 13 peptides bound tightly to GS active pockets with lower binding energies than that of GppNHp. The most potent peptides, LFEIDEELNEK and FATSDLNDLYR, were synthesized, and further experiments showed that these peptides had a highly suppressive effect on GS activity and Aspergillus niger and Penicillium chrysogenum growth. Our results confirm that tryptic treatment is effective for improving the anti-fungal activity of BC. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Rubrofusarin from Aspergillus niger GTS01-4 and its biological activity

    Science.gov (United States)

    Megawati, Dewi, Rizna Triana; Mulyani, Hanny; Maryani, Faiza; Lotullung, Puspa Dewi N.; Minarti

    2017-01-01

    During the research for bioactive secondary metabolites from microorganisms, the terestrial fungi Aspergillus niger GTS01-4 has been investigated for the evaluation of antimicrobial and cytotoxic activities using brine shrimp (Artemia salina) lethality test and MCF-7 cell line. Further chromatographic separation and purification of myselium extract resulted in the isolation identified as rubrofusarin (1). The structure elucidation of isolated compound was performed using 1D-NMR, and LCMS. Furthermore, the cytotoxicity of rubrofusarin (1) was evaluated and resulted with IC50 of 11.51 µg/mL against MCF-7 and LC50 of 368.11 µg/mL against brine shrimp, respectively. However, rubrofusarin (1) showed moderate activity against E. coli, S. aureus, and B. subtilis compared to standard antibiotic, streptomycin. The average zone of inhibition was ranged from 6 to 8 mm at a concentration of 100 µg/disc. These results suggest that rubrofusarin could be a potential candidate in the field of anticancer drug discovery from terrestrial fungi.

  8. Potassium sensing histidine kinase in Bacillus subtilis.

    Science.gov (United States)

    López, Daniel; Gontang, Erin A; Kolter, Roberto

    2010-01-01

    The soil-dwelling organism Bacillus subtilis is able to form multicellular aggregates known as biofilms. It was recently reported that the process of biofilm formation is activated in response to the presence of various, structurally diverse small-molecule natural products. All of these small-molecule natural products made pores in the membrane of the bacterium, causing the leakage of potassium cations from the cytoplasm of the cell. The potassium cation leakage was sensed by the membrane histidine kinase KinC, triggering the genetic pathway to the production of the extracellular matrix that holds cells within the biofilm. This chapter presents the methodology used to characterize the leakage of cytoplasmic potassium as the signal that induces biofilm formation in B. subtilis via activation of KinC. Development of novel techniques to monitor activation of gene expression in microbial populations led us to discover the differentiation of a subpopulation of cells specialized to produce the matrix that holds all cells together within the biofilm. This phenomenon of cell differentiation was previously missed by conventional techniques used to monitor transcriptional gene expression. Copyright © 2010 Elsevier Inc. All rights reserved.

  9. Cannibalism enhances biofilm development in Bacillus subtilis.

    Science.gov (United States)

    López, Daniel; Vlamakis, Hera; Losick, Richard; Kolter, Roberto

    2009-11-01

    Cannibalism is a mechanism to delay sporulation in Bacillus subtilis. Cannibal cells express the skf and sdp toxin systems to lyse a fraction of their sensitive siblings. The lysed cells release nutrients that serve to feed the community, effectively delaying spore formation. Here we provide evidence that the subpopulation of cells that differentiates into cannibals is the same subpopulation that produces the extracellular matrix that holds cells together in biofilms. Cannibalism and matrix formation are both triggered in response to the signalling molecule surfactin. Nutrients released by the cannibalized cells are preferentially used by matrix-producing cells, as they are the only cells expressing resistance to the Skf and Sdp toxins. As a result this subpopulation increases in number and matrix production is enhanced when cannibalism toxins are produced. The cannibal/matrix-producing subpopulation is also generated in response to antimicrobials produced by other microorganisms and may thus constitute a defense mechanism to protect B. subtilis from the action of antibiotics in natural settings.

  10. Hybrid VAR compensator with improved efficiency

    Directory of Open Access Journals (Sweden)

    V. V. Burlaka

    2015-03-01

    Full Text Available In modern electrical networks thyristor-switched capacitors (TSC are most used devices for VAR compensation. These devices don’t contain rotating parts and mechanical contacts, provide a stepwise control of reactive power and no generation of harmonics to the network. However, with the help of TSC it’s not possible to ensure smooth control of reactive power and capacitor banks (CB are exposed to the negative impact of higher harmonic components of the network voltage. Hybrid VAR compensator don’t have such drawbacks. It consists of active filter (AF and capacitor bank with discrete regulation. The main drawback of such systems is the necessity of accessing all six terminals of CB, while most of them are manufactured with three terminals, internally delta-connected. In the article, the topology and control system of hybrid VAR compensator free from beforementioned drawback, is proposed. The control system provides operating modes of overcompensation or undercompensation reactive power. VAR distribution regulator performs redistribution of reactive power between active filter and capacitor banks with the condition to minimize active filter’s power. Scheme of the hybrid VAR compensator, which includes a three-phase three-terminal delta-connected capacitor banks, is shown. Proposed approach allows to provide smooth control of reactive power, isolate the capacitor bank from harmonic currents and use a more effective low-voltage power components

  11. Genetic relationships among strains of the Aspergillus niger aggregate

    DEFF Research Database (Denmark)

    Ferracin, L.M.; Frisvad, Jens Christian; Taniwaki, M.H.

    2009-01-01

    We analyzed the genetic relationships between 51 fungal isolates previously identified as A. niger aggregate, obtained from dried fruit samples from worldwide origin and 7 A. tubingensis obtained from Brazilian coffee beans samples. Greater fungal diversity was found in black sultanas. Aspergillus...... niger sensu stricto was the most prevalent species. It was found in all fruit substrates of all geographical origins. Based on Random Amplification of Polymorphic DNA (RAPD) and beta-tubulin sequences data two groups of A. niger were found. In spite of the small number of isolates from Group IV...

  12. Sticking together: building a biofilm the Bacillus subtilis way.

    Science.gov (United States)

    Vlamakis, Hera; Chai, Yunrong; Beauregard, Pascale; Losick, Richard; Kolter, Roberto

    2013-03-01

    Biofilms are ubiquitous communities of tightly associated bacteria encased in an extracellular matrix. Bacillus subtilis has long served as a robust model organism to examine the molecular mechanisms of biofilm formation, and a number of studies have revealed that this process is regulated by several integrated pathways. In this Review, we focus on the molecular mechanisms that control B. subtilis biofilm assembly, and then briefly summarize the current state of knowledge regarding biofilm disassembly. We also discuss recent progress that has expanded our understanding of B. subtilis biofilm formation on plant roots, which are a natural habitat for this soil bacterium.

  13. Haavelmo's Probability Approach and the Cointegrated VAR

    DEFF Research Database (Denmark)

    Juselius, Katarina

    Some key econometric concepts and problems addressed by Trygve Haavelmo and Ragnar Frisch are discussed within the general frame- work of a cointegrated VAR. The focus is on problems typical of time- series data such as multicollinearity, spurious correlation and regres- sion results, time......) the plausibility of the multivari- ate normality assumption underlying the VAR, (3) cointegration as a solution to the problem of spurious correlation and multicollinearity when data contain deterministic and stochastic trends, (4) the exis- tence of a universe, (5) the association between Frisch’s con...

  14. Volatile components of essential oil from cultivated Myrica gale var. tomentosa and its antioxidant and antimicrobial activities.

    Science.gov (United States)

    Nakata, Mayuko; Myoda, Takao; Wakita, Yoichi; Sato, Takahiro; Tanahashi, Ikuko; Toeda, Kazuki; Fujimori, Takane; Nishizawa, Makoto

    2013-01-01

    Aromatic components in the essential oil prepared from the leaves of cultivated Myrica gale var. tomentosa were compared with those from oil derived wild plants by using gas chromatography-mass spectroscopy (GC/MS). We found that essential oils from both the wild and cultivated plants contained similar aromatic components such as β-elemenone, selina 3,7(11)-diene, myrcene, limonene, cymene, 1,8-cineole, and β-pinene, but the content ratio of the oil was significantly different, which might yield differences in the aromatic properties. The aroma impact components of the essential oils were also determined using GC/MS-Olfactometry (GC/MS-O) and aroma extract dilution analysis. Eight aromatic compounds, including linalool, limonene, and 1,8-cineole, were shown to contribute to the aromatic properties of cultivated M. gale var. tomentosa. The strongest aromatic note was defined as linalool, followed by limonene, 1,8-cineole, and β-elemenone. The essential oil, ethanol (EtOH), 1,3-butylene glycol (BG), and 1,3-propanediol (PD) extracts prepared from the leaves of cultivated M. gale var. tomentosa also showed antioxidant and antimicrobial activities, that is, they demonstrated scavenger activity against hydroxyl and superoxide radicals in the aqueous phase, and showed inhibitory effects on lipid peroxidation. The essential oil extracts also exhibited antimicrobial activity against gram-positive bacteria, with the lowest minimum inhibitory concentration value against Bacillus subtilis. In conclusion, the essential oil and solvent extracts from cultivated M. gala var. tomentosa have a potential for utilization as food and cosmetic ingredients.

  15. Rediscovery of Impatiens laevigata var. grandifolia (Balsaminaceae from NE India

    Directory of Open Access Journals (Sweden)

    R. Gogoi

    2013-12-01

    Full Text Available Impatiens laevigata var. grandifolia Hook.f. rediscovered after a lapse of 139 years from Lohit district of Arunachal Pradesh. Earlier it was known only – from its type locality in Manipur. Detailed morphological description of I. laevigata var. laevigata and var. grandifolia have been provided based on fresh plant collections.

  16. B. oleracea var. capitata monosomic and disomic alien

    Indian Academy of Sciences (India)

    Five monosomic alien addition lines (MAALs) of Brassica rapa ssp. pekinensis – B. oleracea var. capitata were obtained by hybridization and backcrossing between B. rapa ssp. pekinensis (female parent) and B. oleracea var. capitata. The alien linkage groups were identified using 42 B. oleracea var. capitata linkage ...

  17. A singular enzymatic megacomplex from Bacillus subtilis.

    Science.gov (United States)

    Straight, Paul D; Fischbach, Michael A; Walsh, Christopher T; Rudner, David Z; Kolter, Roberto

    2007-01-02

    Nonribosomal peptide synthetases (NRPS), polyketide synthases (PKS), and hybrid NRPS/PKS are of particular interest, because they produce numerous therapeutic agents, have great potential for engineering novel compounds, and are the largest enzymes known. The predicted masses of known enzymatic assembly lines can reach almost 5 megadaltons, dwarfing even the ribosome (approximately 2.6 megadaltons). Despite their uniqueness and importance, little is known about the organization of these enzymes within the native producer cells. Here we report that an 80-kb gene cluster, which occupies approximately 2% of the Bacillus subtilis genome, encodes the subunits of approximately 2.5 megadalton active hybrid NRPS/PKS. Many copies of the NRPS/PKS assemble into a single organelle-like membrane-associated complex of tens to hundreds of megadaltons. Such an enzymatic megacomplex is unprecedented in bacterial subcellular organization and has important implications for engineering novel NRPS/PKSs.

  18. Studies on DNA repair in Bacillus subtilis

    International Nuclear Information System (INIS)

    Inoue, Tadashi; Kada, Tsuneo

    1977-01-01

    An enzyme which enhances the priming activity of γ-irradiated DNA for type I DNA polymerase (EC 2.7.7.7) was identified and partially purified from extracts of Bacillus subtilis cells. The enzyme preferentially degraded γ-irradiated DNA into acid-soluble materials. DNA preparations treated with heat, ultraviolet light, pancreatic DNAase (EC 3.1.4.5) or micrococcal DNAase (EC 3.1.4.7) were not susceptible to the enzyme. However, sonication rendered DNA susceptible to the enzyme to some extent. From these results, it is supposed that this enzyme may function by 'cleaning' damaged terminals produced by γ-irradiation to serve as effective primer of sites for repair synthesis by the type I DNA polymerase

  19. A love affair with Bacillus subtilis.

    Science.gov (United States)

    Losick, Richard

    2015-01-30

    My career in science was launched when I was an undergraduate at Princeton University and reinforced by graduate training at the Massachusetts Institute of Technology. However, it was only after I moved to Harvard University as a junior fellow that my affections were captured by a seemingly mundane soil bacterium. What Bacillus subtilis offered was endless fascinating biological problems (alternative sigma factors, sporulation, swarming, biofilm formation, stochastic cell fate switching) embedded in a uniquely powerful genetic system. Along the way, my career in science became inseparably interwoven with teaching and mentoring, which proved to be as rewarding as the thrill of discovery. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. Bacillus subtilis as potential producer for polyhydroxyalkanoates

    Directory of Open Access Journals (Sweden)

    Patel Sanjay KS

    2009-07-01

    Full Text Available Abstract Polyhydroxyalkanoates (PHAs are biodegradable polymers produced by microbes to overcome environmental stress. Commercial production of PHAs is limited by the high cost of production compared to conventional plastics. Another hindrance is the brittle nature and low strength of polyhydroxybutyrate (PHB, the most widely studied PHA. The needs are to produce PHAs, which have better elastomeric properties suitable for biomedical applications, preferably from inexpensive renewable sources to reduce cost. Certain unique properties of Bacillus subtilis such as lack of the toxic lipo-polysaccharides, expression of self-lysing genes on completion of PHA biosynthetic process – for easy and timely recovery, usage of biowastes as feed enable it to compete as potential candidate for commercial production of PHA.

  1. Bacillus subtilis as potential producer for polyhydroxyalkanoates.

    Science.gov (United States)

    Singh, Mamtesh; Patel, Sanjay Ks; Kalia, Vipin C

    2009-07-20

    Polyhydroxyalkanoates (PHAs) are biodegradable polymers produced by microbes to overcome environmental stress. Commercial production of PHAs is limited by the high cost of production compared to conventional plastics. Another hindrance is the brittle nature and low strength of polyhydroxybutyrate (PHB), the most widely studied PHA. The needs are to produce PHAs, which have better elastomeric properties suitable for biomedical applications, preferably from inexpensive renewable sources to reduce cost. Certain unique properties of Bacillus subtilis such as lack of the toxic lipo-polysaccharides, expression of self-lysing genes on completion of PHA biosynthetic process - for easy and timely recovery, usage of biowastes as feed enable it to compete as potential candidate for commercial production of PHA.

  2. Effect of simulated microgravity on Aspergillus niger

    Science.gov (United States)

    Pratap, Jeffrey J.

    2005-08-01

    A rotating bioreactor was developed to simulate microgravity and its influence was studied on fungal growth. The reactor was designed to simulate microgravity using 'free fall' principle, which creates an apparent weightlessness for a brief period of time. In this experiment, a sealed vertically rotating tube is the reactor in which the cells are grown. For the first time vertically rotating tubes were used to obtain 'free fall' thereby simulating microgravity. Simulated microgravity served significant in the alteration of growth and productivity of Aspergillus niger, a common soil fungi. Two other sets of similar cultures were maintained as still and shake control cultures to compare with the growth and productivity of cells in rotating culture. It was found increased growth and productivity occurred in simulated microgravity. Since this experiment involves growth of cells in a liquid medium, the fluidic effects must also be studied which is a limitation.

  3. Two uranium mines in Niger: Somair Cominak

    International Nuclear Information System (INIS)

    Caleix, C.; Renardet, P.

    1987-01-01

    The research work undertaken by the Atomic Energy Commission on the territory of the Republic of the Niger has led to the discovery of two major uranium deposits, Arlit and Akouta, which are situated at the of the Sahara to the West of the massif of l'Air at approximately 850 km from Niamey. These deposits are exploited by two firms according to Nigerian law with a head office at Niamey. The firm Somair acts for Arlit and operates an open pit; the mining company Akouta works the Akouta deposit which is deeper and entails an underground operation. The production capacities are 2300 t and 2000 t of uranium metal per year, respectively [fr

  4. Nutrient enrichment of pineapple waste using Aspergillus niger and ...

    African Journals Online (AJOL)

    Nutrient enrichment of pineapple waste using Aspergillus niger and Trichoderma viride by solid state fermentation. Evans Otieno Omwango, Eliud Nyaga Mwaniki Njagi, George Owino Orinda, Ruth Nduta Wanjau ...

  5. Pectinolytic complex production by Aspergillus niger URM 4645 ...

    African Journals Online (AJOL)

    -PG), pectin lyase (PL), and pectin methylesterase (PE), produced by Aspergillus niger URM 4645, were studied in solid state fermentation (SSF) using yellow passion fruit peels as substrate. The effect of substrate amount, initial moisture ...

  6. The Niger Delta Avengers, Autonomous Ethnic Clans and Common ...

    African Journals Online (AJOL)

    Nneka Umera-Okeke

    therefore investigated the sudden emergence of Niger Delta Avengers ... hardship, deprivations and environmental degradation occasioned by oil pipeline .... analysis of coded materials of the library such as books, magazines, journals,.

  7. Contribution of arginase to manganese metabolism of Aspergillus niger.

    Science.gov (United States)

    Keni, Sarita; Punekar, Narayan S

    2016-02-01

    Aspects of manganese metabolism during normal and acidogenic growth of Aspergillus niger were explored. Arginase from this fungus was a Mn[II]-enzyme. The contribution of the arginase protein towards A. niger manganese metabolism was investigated using arginase knockout (D-42) and arginase over-expressing (ΔXCA-29) strains of A. niger NCIM 565. The Mn[II] contents of various mycelial fractions were found in the order: D-42 strain niger mycelia harvested from acidogenic growth media contain substantially less Mn[II] as compared to those from normal growth media. Nevertheless, acidogenic mycelia harbor considerable Mn[II] levels and a functional arginase. Altered levels of mycelial arginase protein did not significantly influence citric acid production. The relevance of arginase to cellular Mn[II] pool and homeostasis was evaluated and the results suggest that arginase regulation could occur via manganese availability.

  8. Environmental Law and Underdevelopment in the Niger Delta ...

    African Journals Online (AJOL)

    Environmental Law and Underdevelopment in the Niger Delta Region of Nigeria. ... is composed of many ecosystems of great economic and social importance, ... producing companies contribute to the degradation of the environment which in ...

  9. Assessing transportation and road conditions in niger state, nigeria ...

    African Journals Online (AJOL)

    Assessing transportation and road conditions in niger state, nigeria using geoinformatics, with focus on impact of climate ... Also the impacts of climate change on transportation were highlighted. ... EMAIL FULL TEXT EMAIL FULL TEXT

  10. Pattern of Complicated Unsafe Abortions in Niger Delta University ...

    African Journals Online (AJOL)

    Alasia Datonye

    of cases of complicated unsafe abortion managed at the. Niger Delta University ... previous termination of pregnancy and 87.3% of the patients had ... and outcome were obtained. ... life-threatening complications, post- abortion family planning.

  11. Fumonisins in Aspergillus niger: Industrial and food aspects

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Nielsen, Kristian Fog; Mogensen, Jesper

    Introduction: Fumonisins are toxic seconday metabolites from Fusarium verticillioides and other Fusaria, from Tolypocladium and Aspergillus niger 1,2. Being a generalist Aspergillus niger is the workhorse in a very large number of industrial applications, and is also a common contaminant in foods....... Fumonisin production by A. niger is depending on temperature and water activity, but is produced mostly on substrates with high maounts of sugar or salt 1,3,4. We wanted to find out whether industrial strains could produce fumonisins in worst case scenarios and if fumonisin production was only a feature...... ever used in biotechnology could produce fuminisins B2, B4 & B6. The strains could be subdivided into two clades (representing A. niger and the “phylospecies” A. awamori), and there were fumonisin producers in both clades. Ochratoxin A was also produced by strains in both clades, but only...

  12. Biominerlization and possible endosulfan degradation pathway adapted by Aspergillus niger.

    Science.gov (United States)

    Bhalerao, Tejomyee S

    2013-11-28

    Endosulfan is a chlorinated pesticide; its persistence in the environment and toxic effects on biota are demanding its removal. This study aims at improving the tolerance of the previously isolated fungus Aspergillus niger (A. niger) ARIFCC 1053 to endosulfan. Released chloride, dehalogenase activity, and released proteins were estimated along with analysis of endosulfan degradation and pathway identification. The culture could tolerate 1,000 mg/ml of technical grade endosulfan. Complete disappearance of endosulfan was seen after 168 h of incubation. The degradation study could easily be correlated with increase in released chlorides, dehalogenase activity and protein released. Comparative infrared spectral analysis suggested that the molecule of endosulfan was degraded efficiently by A. niger ARIFCC 1053. Obtained mass ion values by GC-MS suggested a hypothetical pathway during endosulfan degradation by A. niger ARIFCC 1053. All these results provide a basis for the development of bioremediation strategies to remediate the pollutant under study in the environment.

  13. What are Pregnant Women in a Rural Niger Delta Community's ...

    African Journals Online (AJOL)

    Erah

    Buchanan House, Glasgow Caledonian University Email: Caroline. ... exploratory qualitative study was carried out to identify pregnant women in a rural Niger Delta community's perceptions of ..... sometimes you stay for the whole day.

  14. stabilization of dredged spoils for pavement construction in the niger

    African Journals Online (AJOL)

    Dr. Tse

    Natural soils underlying the East-West road are mainly clay and silt of poor quality ... on the dredged soils included particle size distribution, compaction and California ... KEYWORDS: Stabilization, dredge spoil, pavement, Niger Delta, cement.

  15. Control of Aspergillus niger with garlic, onion and leek extracts

    African Journals Online (AJOL)

    Administrator

    2007-02-19

    Feb 19, 2007 ... Key words: Aspergillus niger, garlic, onion, leek, antifungal activity. ..... Antimicrobial activity of essential oil extracts of various onions (Allium cepa) ... activity of oregano and thyme essential oils applied as fumigants against.

  16. Global network reorganization during dynamic adaptations of Bacillus subtilis metabolism

    DEFF Research Database (Denmark)

    Buescher, Joerg Martin; Liebermeister, Wolfram; Jules, Matthieu

    2012-01-01

    Adaptation of cells to environmental changes requires dynamic interactions between metabolic and regulatory networks, but studies typically address only one or a few layers of regulation. For nutritional shifts between two preferred carbon sources of Bacillus subtilis, we combined statistical...

  17. Two Genes Encoding Uracil Phosphoribosyltransferase Are Present in Bacillus subtilis

    DEFF Research Database (Denmark)

    Martinussen, Jan; Glaser, Philippe; Andersen, Paal S.

    1995-01-01

    Uracil phosphoribosyltransferase (UPRTase) catalyzes the key reaction in the salvage of uracil in many microorganisms. Surprisingly, two genes encoding UPRTase activity were cloned from Bacillus subtilis by complementation of an Escherichia coli mutant. The genes were sequenced, and the putative...

  18. Production of alkaline proteases by alkalophilic Bacillus subtilis ...

    African Journals Online (AJOL)

    Tuoyo Aghomotsegin

    2016-11-23

    Nov 23, 2016 ... Key words: Production, alkaline protease, Bacillus subtilis, animal wastes, enzyme activity. ... Generally, alkaline proteases are produced using submerged fermentation .... biopolymer concentrations were reported to have an influence ... adding nitrogenous compounds stimulate microorganism growth and ...

  19. Enhanced biomass production study on probiotic Bacillus subtilis ...

    African Journals Online (AJOL)

    user

    2010-11-22

    Nov 22, 2010 ... INTRODUCTION. Probiotic organisms find their potential use in food and ..... complex nutrients, temperature and pH on bacteriocin production by. Bacillus subtilis ... B, Gupta R (2004). Application of statistical experimental.

  20. Induced mutant for male sterility in niger

    International Nuclear Information System (INIS)

    Sujatha, M.

    2001-01-01

    Full text: Niger (Guizotia abyssinica Cass.), an important oilseed crop of the family Compositae is highly cross-pollinated due to the twin mechanisms of protandry and incompatibility. Studies revealed the functional nature of protandry and the breakdown of incompatibility with alteration in temperature. It has very small flowers (disc florets) arranged in a capitulum that open on 3-4 consecutive days which pose problems in emasculation for cross-breeding. To induce mutations, seeds of variety 'IGP-76' were irradiated with γ-rays 200 to 1000 Gy. All seeds of M 1 plants were sown separately in individual plant-to progeny rows. The results of screening of M 2 segregating material indicated that γ-ray treatment was effective in induction of male sterility. Frequency of visible mutations were higher in sibbed progeny as compared to open pollinated population and male sterile plants were observed only in sibbed population (1000 Gy). Male sterile plants could easily be identified at the flowering stage by their altered floral morphology (disc florets transformed into ligulate ray florets) and complete absence or presence of a rudimentary anther column. Seeds were collected following sib-mating with the fertile counterparts. Progeny segregated in a ration of 3 normal : 1 male sterile. Further work on the mechanism of sterility, maintenance and linkage relationships with associated characters is under progress. This is the first report of induction of male sterility in niger through the use of physical mutagens. The availability of this mutant will be of great value for exploitation of heterosis on commercial basis. (author)

  1. Single cell transcriptomics of neighboring hyphae of Aspergillus niger

    Science.gov (United States)

    2011-01-01

    Single cell profiling was performed to assess differences in RNA accumulation in neighboring hyphae of the fungus Aspergillus niger. A protocol was developed to isolate and amplify RNA from single hyphae or parts thereof. Microarray analysis resulted in a present call for 4 to 7% of the A. niger genes, of which 12% showed heterogeneous RNA levels. These genes belonged to a wide range of gene categories. PMID:21816052

  2. Selection of tannase-producing Aspergillus niger strains

    OpenAIRE

    Pinto,Gustavo A.S.; Leite,Selma G.F.; Terzi,Selma C.; Couri,Sonia

    2001-01-01

    The aim of this work was to select strains of Aspergillus niger for tannase production. Growth of colonies in plates with tannic acid-containing medium indicated their ability to synthesize tannase. Tannase activity was also measured in solid-state fermentation. A. niger 11T25A5 was the best tannase producer (67.5 U.g-1/72 hours of fermentation).

  3. Fitness Trade-Offs in Competence Differentiation of Bacillus subtilis

    OpenAIRE

    Yüksel, Melih; Power, Jeffrey J.; Ribbe, Jan; Volkmann, Thorsten; Maier, Berenike

    2016-01-01

    In the stationary phase, Bacillus subtilis differentiates stochastically and transiently into the state of competence for transformation (K-state). The latter is associated with growth arrest, and it is unclear how the ability to develop competence is stably maintained, despite its cost. To quantify the effect differentiation has on the competitive fitness of B. subtilis, we characterized the competition dynamics between strains with different probabilities of entering the K-state. The relati...

  4. Teucrium pruinosum var. aksarayense var. nov. (Lamiaceae from Central Anatolia, Turkey

    Directory of Open Access Journals (Sweden)

    Muhittin Dinç

    2016-06-01

    Full Text Available Teucrium pruinosum var. aksarayense M. Dinç & S. Doğu (Lamiaceae, a new variety from Aksaray in Central Anatolia, is described and illustrated. The new variety is similar to the typical one in its calyx teeth uncinate at tip and subequal to the tube with conspicious midvein. It is readily distinguished from var. pruinosum by its general appearance, indumentum, and floral organ pigmentation. The map showing the distributions of the varieties was given.

  5. What is Orobanche haenseleri var. deludens Beck?

    Directory of Open Access Journals (Sweden)

    Pujadas Salvà, Antonio J.

    2004-12-01

    Full Text Available Orobanche haenseleri var. deludens Beck (Orobanchaceae, a problematic taxon described from Algeciras (Cádiz, S Spain is here identified after studying the original material of Wolley-Dod (BM 4476. It is considered to be the same as O. austrohispanica M.J.Y. Foley and better included, as a variety, under O. gracilis Sm. The new combination O. gracilis var. deludens (Beck A. Pujadas is consequently proposed. It mainly parasites Ulex (Fabaceae in the western Mediterranean Region (Iberian Peninsula and NW Africa.Se identifica Orobanche haenseleri var. deludens Beck (Orobanchaceae, un taxon conflictivo descrito de Algeciras (Cádiz, sur de España, a partir del análisis del material original de Wolley-Dod (BM 4476. Se considera que es lo mismo que O. austrohispanica M.J.Y. Foley, y se incluye en O. gracilis Sm. con rango varietal. Se propone la nueva combinación O. gracilis var. deludens (Beck A. Pujadas. Parasita principalmente a especies del género Ulex (Fabaceae en la Región Mediterránea Occidental (Península Ibérica y noroeste de África.

  6. Is Solanum ferox var. ferox (Solanaceae) extinct?

    NARCIS (Netherlands)

    Heiser, C.B.

    2001-01-01

    In 1995 I wrote letters to over 50 people (botanists, agricultural scientists, and former students of Indiana University) in south-eastern Asia trying to obtain a few seeds of Solanumferox L. var. ferox (S. involucratum Blume). I had over 25 replies, five of which included seeds, but none of the

  7. Anogeissus sericea var. nummalaria King ex Duthie

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 8; Issue 4. Anogeissus sericea var. nummalaria King ex Duthie. Flowering Trees Volume 8 Issue 4 April 2003 pp 89-89. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/008/04/0089-0089. Resonance ...

  8. Var der noget kapløb?

    DEFF Research Database (Denmark)

    Gimpel, Denise; Nielsen, Bent

    2006-01-01

    Hvorfor faldt Kina bagud i kapløbet med Vesten?« spørger David Favrholdt i sidste nummer af Weekendavisen. Var der overhovedet noget kapløb? Forudsætter et kapløb ikke, at man har et fælles mål? Spørgsmålet implicerer, at Vesten har vundet og indplacerer samtidig klodens øvrige kulturer i forhold....... Som en af 1900-tallets største sinologer A. C. Graham skriver i sin bog Disputers of the Tao (La Salle, Ill., 1989) var den videnskabelige revolution »en unik og kompleks begivenhed, som var afhængig af en mangfoldighed af sociale og andre betingelser, herunder et sammenfald af opdagelser (græske......, indiske, kinesiske, arabiske, næsten ingen romerske) koncentreret om kombinationen af indiske tal og aritmetik og græsk logik og geometri« (s. 317). En unik begivenhed, som er forekommet én gang i verdenshistorien. Det giver derfor ingen mening at spørge, hvorfor det ikke skete andre steder. Hvis det var...

  9. Global transcriptional responses of Bacillus subtilis to xenocoumacin 1.

    Science.gov (United States)

    Zhou, T; Zeng, H; Qiu, D; Yang, X; Wang, B; Chen, M; Guo, L; Wang, S

    2011-09-01

    To determine the global transcriptional response of Bacillus subtilis to an antimicrobial agent, xenocoumacin 1 (Xcn1). Subinhibitory concentration of Xcn1 applied to B. subtilis was measured according to Hutter's method for determining optimal concentrations. cDNA microarray technology was used to study the global transcriptional response of B. subtilis to Xcn1. Real-time RT-PCR was employed to verify alterations in the transcript levels of six genes. The subinhibitory concentration was determined to be 1 μg ml(-1). The microarray data demonstrated that Xcn1 treatment of B. subtilis led to more than a 2.0-fold up-regulation of 480 genes and more than a 2.0-fold down-regulation of 479 genes (q ≤ 0.05). The transcriptional responses of B. subtilis to Xcn1 were determined, and several processes were affected by Xcn1. Additionally, cluster analysis of gene expression profiles after treatment with Xcn1 or 37 previously studied antibiotics indicated that Xcn1 has similar mechanisms of action to protein synthesis inhibitors. These microarray data showed alterations of gene expression in B. subtilis after exposure to Xcn1. From the results, we identified various processes affected by Xcn1. This study provides a whole-genome perspective to elucidate the action of Xcn1 as a potential antimicrobial agent. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

  10. Bacillus subtilis strain specificity affects performance improvement in broilers.

    Science.gov (United States)

    Rhayat, L; Jacquier, V; Brinch, K S; Nielsen, P; Nelson, A; Geraert, P-A; Devillard, E

    2017-07-01

    The study reports the effects on broiler performance of a newly isolated Bacillus subtilis strain, which is phylogenetically not closely related to already well-described strains of B. subtilis. In the first experiment, birds were reared in battery cages and exposed to C. perfringens. An increase in growth performance was observed with the strain when compared to the challenged animals. Three additional growth trials were conducted to 35 d of age, in different rearing conditions (genetic breeds, corn-soybean meal-based diet with or without animal proteins, in presence or absence of phytase, on fresh or used litter) to investigate the efficacy and the specificity of this new B. subtilis strain on the improvement of BWG and FCR of broilers in comparison with a B. subtilis-based DFM already used in the field. Whatever the rearing conditions tested, the new B. subtilis strain led to an average 3.2% improvement in feed conversion ratio or bodyweight. Comparatively, the commercial Bacillus strain significantly improved broiler performance in only one trial out of 3 with an average improvement reaching 2%. All these results indicate that this new B. subtilis strain consistently improves broiler performances. © 2017 Poultry Science Association Inc.

  11. Analysis list: Su(var)205 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Su(var)205 Adult,Embryo,Larvae + dm3 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3.../target/Su(var)205.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/target/Su(var)205.5.tsv http://dbarc...hive.biosciencedbc.jp/kyushu-u/dm3/target/Su(var)205.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/c...olo/Su(var)205.Adult.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/colo/Su(var)205.Embryo.tsv,http:...//dbarchive.biosciencedbc.jp/kyushu-u/dm3/colo/Su(var)205.Larvae.tsv http://dbarchive

  12. Chemical compounds and antimicrobial activity of petitgrain (Citrus aurantium L. var. amara essential oil

    Directory of Open Access Journals (Sweden)

    Gniewosz Małgorzata

    2017-12-01

    Full Text Available Introduction: Due to its low cost and easy availability on the market, the petitgrain oil is commonly used in food, cosmetics, and aromatherapy. Objective: The examination of chemical composition and antibacterial activity of commercial petitgrain oil. Methods: Identification of chemical components of the petitgrain oil was performed by gas chromatography (GC. The minimum inhibitory concentrations (MIC and minimum bactericidal/fungicidal concentrations (MBC/MFC were determined using macrodilution method for the reference strains of bacteria and fungi. Results: Twenty components were identified. The petitgrain oil contained mostly oxygenated monoterpene hydrocarbons (98.01%, and the main components included linalyl acetate (48.06% and linalool (26.88%. The MIC/MBC of the petitgrain oil for bacteria was in the range of 0.63-5.0/1.25-5.0 mg/ml and for fungi in the range of 1.25-40/5.0-80 mg/ml. Conclusion: The petitgrain oil had higher antibacterial activity than antifungal activity. Bacillus subtilis among the tested bacteria and Aspergillus niger and Penicillium expansum among the fungi were found to be highly inhibited by the petitgrain oil.

  13. The situation in the Niger Delta; La situation dans le delta du Niger

    Energy Technology Data Exchange (ETDEWEB)

    Vitalis, E

    2007-07-15

    An energy issue for the United States and a political challenge for Europe, Nigeria is experiencing growing instability and is on the verge of civil war; the ecosystem and the population of the Niger Delta are the main victims. The State, corrupt, is powerless to contain the rising violence and redistribute the proceeds of oil sales. It is high time for oil-consuming countries, starting with the United States, to concern themselves with stabilizing the region. Europe must contribute to the lasting development of this country. (author)

  14. Aspergillus niger: an unusual cause of invasive pulmonary aspergillosis

    Science.gov (United States)

    Person, A. K.; Chudgar, S. M.; Norton, B. L.; Tong, B. C.; Stout, J. E.

    2010-01-01

    Infections due to Aspergillus species cause significant morbidity and mortality. Most are attributed to Aspergillus fumigatus, followed by Aspergillus flavus and Aspergillus terreus. Aspergillus niger is a mould that is rarely reported as a cause of pneumonia. A 72-year-old female with chronic obstructive pulmonary disease and temporal arteritis being treated with steroids long term presented with haemoptysis and pleuritic chest pain. Chest radiography revealed areas of heterogeneous consolidation with cavitation in the right upper lobe of the lung. Induced bacterial sputum cultures, and acid-fast smears and cultures were negative. Fungal sputum cultures grew A. niger. The patient clinically improved on a combination therapy of empiric antibacterials and voriconazole, followed by voriconazole monotherapy. After 4 weeks of voriconazole therapy, however, repeat chest computed tomography scanning showed a significant progression of the infection and near-complete necrosis of the right upper lobe of the lung. Serum voriconazole levels were low–normal (1.0 μg ml−1, normal range for the assay 0.5–6.0 μg ml−1). A. niger was again recovered from bronchoalveolar lavage specimens. A right upper lobectomy was performed, and lung tissue cultures grew A. niger. Furthermore, the lung histopathology showed acute and organizing pneumonia, fungal hyphae and oxalate crystallosis, confirming the diagnosis of invasive A. niger infection. A. niger, unlike A. fumigatus and A. flavus, is less commonly considered a cause of invasive aspergillosis (IA). The finding of calcium oxalate crystals in histopathology specimens is classic for A. niger infection and can be helpful in making a diagnosis even in the absence of conidia. Therapeutic drug monitoring may be useful in optimizing the treatment of IA given the wide variations in the oral bioavailability of voriconazole. PMID:20299503

  15. Antibacterial effects of ellagitannins from Acalypha wilkesiana var. macafeana hort.: surface morphology analysis with environmental scanning electron microscopy and synergy with antibiotics.

    Science.gov (United States)

    Din, Wardah Mustafa; Jin, Khoo Teng; Ramli, Ramliza; Khaithir, Tzar Mohd Nizam; Wiart, Christophe

    2013-09-01

    The present study served to gain further insight into the bactericidal effects of ellagitannins from Acalypha wilkesiana var. macafeana hort. against pathogenic bacteria. Ellagitannins from the aerial parts of A. wilkesiana var. macafeana hort. (EAW) inhibited the growth of Bacillus cereus (ATCC 11778), Bacillus subtilis (ATCC 6633), Staphylococcus aureus (ATCC 11632) and Methicillin-resistant Staphylococcus aureus (MRSA) clinical strain with inhibition zones equal to 11.01 ± 1.53 mm, 16.63 ± 0.11 mm, 11.40 ± 1.10 mm and 8.22 ± 0.19 mm, respectively. The minimal inhibition concentration and the minimal bactericidal concentration of ellagitannins from A. wilkesiana var. macafeana hort. (EAW) against MRSA were 750 µg/mL and 3000 µg/mL, respectively. We then examined the synergistic effect of EAW with three antibiotics, i.e. ampicillin, streptomycin and tetracycline, via the checkerboard assay and time-kill assay and observed that EAW is synergistic with ampicillin against S. aureus (ATCC 11632). Environmental electron scanning microscopy analysis showed cell lysis against S. aureus (ATCC 11632) upon treatment with the ellagitannin fraction. The ellagitannin fraction from A. wilkesiana var. macafeana hort. is bactericidal against gram-positive bacteria tested and works synergistically with ampicillin against S. aureus. Morphology analysis of the cell suggests that the bactericidal property of the ellagitannin fraction mechanism involves lysis of the cell wall. In summary, our studies demonstrate that A. wilkesiana var. macafeana hort. produces bactericidal ellagitannins of clinical and/or cosmetological value. Copyright © 2012 John Wiley & Sons, Ltd.

  16. Bistability and Biofilm Formation in Bacillus subtilis

    Science.gov (United States)

    Chai, Yunrong; Chu, Frances; Kolter, Roberto; Losick, Richard

    2008-01-01

    Summary Biofilms of Bacillus subtilis consist of long chains of cells that are held together in bundles by an extracellular matrix of exopolysaccharide and the protein TasA. The exopolysaccharide is produced by enzymes encoded by the epsA-O operon and the gene encoding TasA is located in the yqxM-sipW-tasA operon. Both operons are under the control of the repressor SinR. Derepression is mediated by the antirepressor SinI, which binds to SinR with a 1:1 stoichiometry. Paradoxically, in medium promoting derepression of the matrix operons, the overall concentration of SinR in the culture greatly exceeded that of SinI. We show that under biofilm-promoting conditions sinI, which is under the control of the response regulator Spo0A, was expressed only in a small subpopulation of cells, whereas sinR was expressed in almost all cells. Activation of Spo0A is known to be subject to a bistable switch, and we infer that SinI reaches levels sufficient to trigger matrix production only in the subpopulation of cells in which Spo0A is active. Additionally, evidence suggests that sinI is expressed at intermediate, but not low or high, levels of Spo0A activity, which may explain why certain nutritional conditions are more effective in promoting biofilm formation than others. PMID:18047568

  17. Applications of the absolute reaction rate theory to biological responses in electric and magnetic fields

    International Nuclear Information System (INIS)

    Brannen, J.P.; Wayland, J.R.

    1976-01-01

    This paper develops a theoretical foundation for the study of biological responses of electric and magnetic fields. The basis of the development is the absolute reaction rate theory and the effects of fields on reaction rates. A simple application to the response of Bacillus subtilis var niger in a microwave field is made. Potential areas of application are discussed

  18. Nutritional characteristics of forages from Niger

    Directory of Open Access Journals (Sweden)

    F. Infascelli

    2010-04-01

    Full Text Available In the production systems of the semi-arid areas low quality forages are commonly used as the basal diet (Wilkins, 2000 and, as a consequence, the nutritional status of ruminants depends mainly on the ability of rumen fermentation to yield nutrients such as the short chain fatty acids and microbial biomass (Preston and Leng, 1987. The forages browsed by the livestock can be classified into two main groups: ephemeral annual plants, which germinate and remain green for only a few weeks after rain, perennial shrubs and tree fodders. Despite their potential as feeds, little research has determined their nutritive value. In vivo evaluation is the best estimation method of feed’s nutritional value, however it is very laborious and difficult to standardize with browsing animals. O the contrary, in vitro methods are less expensive, less time consuming and allow a better control of experimental conditions than in vivo experiments. The in vitro gas production technique (IVGPT appears to be the most suitable method for use in developing countries where resources may be limited (Makkar, 2004. Increased interest in use of non-conventional feed resources has led to an increase in use of this technique, since IVGPT can provide useful data on digestion kinetics of both the soluble and insoluble fractions of feedstuffs. The aim of the present research was to evaluate twelve forages from the arid zone of Niger using the IVGPT.

  19. Homolactic fermentation from glucose and cellobiose using Bacillus subtilis

    Directory of Open Access Journals (Sweden)

    Martinez Alfredo

    2009-04-01

    Full Text Available Abstract Backgroung Biodegradable plastics can be made from polylactate, which is a polymer made from lactic acid. This compound can be produced from renewable resources as substrates using microorganisms. Bacillus subtilis is a Gram-positive bacterium recognized as a GRAS microorganism (generally regarded as safe by the FDA. B. subtilis produces and secretes different kind of enzymes, such as proteases, cellulases, xylanases and amylases to utilize carbon sources more complex than the monosaccharides present in the environment. Thus, B. subtilis could be potentially used to hydrolyze carbohydrate polymers contained in lignocellulosic biomass to produce chemical commodities. Enzymatic hydrolysis of the cellulosic fraction of agroindustrial wastes produces cellobiose and a lower amount of glucose. Under aerobic conditions, B. subtilis grows using cellobiose as substrate. Results In this study, we proved that under non-aerated conditions, B. subtilis ferments cellobiose to produce L-lactate with 82% of the theoretical yield, and with a specific rate of L-lactate production similar to that one obtained fermenting glucose. Under fermentative conditions in a complex media supplemented with glucose, B. subtilis produces L-lactate and a low amount of 2,3-butanediol. To increase the L-lactate production of this organism, we generated the B subtilis CH1 alsS- strain that lacks the ability to synthesize 2,3-butanediol. Inactivation of this pathway, that competed for pyruvate availability, let a 15% increase in L-lactate yield from glucose compared with the parental strain. CH1 alsS- fermented 5 and 10% of glucose to completion in mineral medium supplemented with yeast extract in four and nine days, respectively. CH1 alsS- produced 105 g/L of L-lactate in this last medium supplemented with 10% of glucose. The L-lactate yield was up to 95% using mineral media, and the optical purity of L-lactate was of 99.5% since B. subtilis has only one gene (lctE that

  20. Aspergillus niger contains the cryptic phylogenetic species A. awamori.

    Science.gov (United States)

    Perrone, Giancarlo; Stea, Gaetano; Epifani, Filomena; Varga, János; Frisvad, Jens C; Samson, Robert A

    2011-11-01

    Aspergillus section Nigri is an important group of species for food and medical mycology, and biotechnology. The Aspergillus niger 'aggregate' represents its most complicated taxonomic subgroup containing eight morphologically indistinguishable taxa: A. niger, Aspergillus tubingensis, Aspergillus acidus, Aspergillus brasiliensis, Aspergillus costaricaensis, Aspergillus lacticoffeatus, Aspergillus piperis, and Aspergillus vadensis. Aspergillus awamori, first described by Nakazawa, has been compared taxonomically with other black aspergilli and recently it has been treated as a synonym of A. niger. Phylogenetic analyses of sequences generated from portions of three genes coding for the proteins β-tubulin (benA), calmodulin (CaM), and the translation elongation factor-1 alpha (TEF-1α) of a population of A. niger strains isolated from grapes in Europe revealed the presence of a cryptic phylogenetic species within this population, A. awamori. Morphological, physiological, ecological and chemical data overlap occurred between A. niger and the cryptic A. awamori, however the splitting of these two species was also supported by AFLP analysis of the full genome. Isolates in both phylospecies can produce the mycotoxins ochratoxin A and fumonisin B₂, and they also share the production of pyranonigrin A, tensidol B, funalenone, malformins, and naphtho-γ-pyrones. In addition, sequence analysis of four putative A. awamori strains from Japan, used in the koji industrial fermentation, revealed that none of these strains belong to the A. awamori phylospecies. Copyright © 2011 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  1. Transcriptome analysis of Aspergillus niger grown on sugarcane bagasse

    Science.gov (United States)

    2011-01-01

    Background Considering that the costs of cellulases and hemicellulases contribute substantially to the price of bioethanol, new studies aimed at understanding and improving cellulase efficiency and productivity are of paramount importance. Aspergillus niger has been shown to produce a wide spectrum of polysaccharide hydrolytic enzymes. To understand how to improve enzymatic cocktails that can hydrolyze pretreated sugarcane bagasse, we used a genomics approach to investigate which genes and pathways are transcriptionally modulated during growth of A. niger on steam-exploded sugarcane bagasse (SEB). Results Herein we report the main cellulase- and hemicellulase-encoding genes with increased expression during growth on SEB. We also sought to determine whether the mRNA accumulation of several SEB-induced genes encoding putative transporters is induced by xylose and dependent on glucose. We identified 18 (58% of A. niger predicted cellulases) and 21 (58% of A. niger predicted hemicellulases) cellulase- and hemicellulase-encoding genes, respectively, that were highly expressed during growth on SEB. Conclusions Degradation of sugarcane bagasse requires production of many different enzymes which are regulated by the type and complexity of the available substrate. Our presently reported work opens new possibilities for understanding sugarcane biomass saccharification by A. niger hydrolases and for the construction of more efficient enzymatic cocktails for second-generation bioethanol. PMID:22008461

  2. Transcriptome analysis of Aspergillus niger grown on sugarcane bagasse

    Directory of Open Access Journals (Sweden)

    Goldman Gustavo H

    2011-10-01

    Full Text Available Abstract Background Considering that the costs of cellulases and hemicellulases contribute substantially to the price of bioethanol, new studies aimed at understanding and improving cellulase efficiency and productivity are of paramount importance. Aspergillus niger has been shown to produce a wide spectrum of polysaccharide hydrolytic enzymes. To understand how to improve enzymatic cocktails that can hydrolyze pretreated sugarcane bagasse, we used a genomics approach to investigate which genes and pathways are transcriptionally modulated during growth of A. niger on steam-exploded sugarcane bagasse (SEB. Results Herein we report the main cellulase- and hemicellulase-encoding genes with increased expression during growth on SEB. We also sought to determine whether the mRNA accumulation of several SEB-induced genes encoding putative transporters is induced by xylose and dependent on glucose. We identified 18 (58% of A. niger predicted cellulases and 21 (58% of A. niger predicted hemicellulases cellulase- and hemicellulase-encoding genes, respectively, that were highly expressed during growth on SEB. Conclusions Degradation of sugarcane bagasse requires production of many different enzymes which are regulated by the type and complexity of the available substrate. Our presently reported work opens new possibilities for understanding sugarcane biomass saccharification by A. niger hydrolases and for the construction of more efficient enzymatic cocktails for second-generation bioethanol.

  3. Production of Bioactive Compounds by Bacillus subtilis against Sclerotium rolfsii

    Directory of Open Access Journals (Sweden)

    Nalisha, I.

    2006-01-01

    Full Text Available This study aims to investigate the characteristic of bioactive compound produced by Bacillus subtilis against Sclerotium rolfsii and the influence of additive supplements on the antagonistic activity of B. subtilis. The fact that B. subtilis produced an antifungal substance which has inhibitory effect on wide range of fungi, including S. rolfsii, is well known. To learn the effect of pH, temperature and light condition on the production of antifungal compound, B. subtilis was inoculated in Potato Dextrose Broth at various initial pH, temperatures and light conditions, respectively. This antagonist was found to produce antifungal compound that stable at 80C with 58.3 % inhibition on S. rolfsii. The activity was constant within a wide range of pH (3–11. However, treatment with pH11 lead to higher antifungal activity (31.57 % inhibition and it was also found to produce substance that can endure dark condition (46.24 % inhibition with fungicidal effect on S. rolfsii. A series of experiments also been carried out to enhance the antifungal production by supplementing different carbon source preparation into bacterial liquid culture. B. subtilis were grown in minimal medium containing 1 % of oil palm root, Ganoderma lucidum or chitin, respectively prior to bioassay. Crude culture from oil palm root supplemented culture shown significantly reduction in S. rolfsii growth compared to other carbon source crude culture or the antagonism alone, suggesting that this approach may provide improved biocontrol efficiency.

  4. Removing Bacillus subtilis from fermentation broth using alumina nanoparticles.

    Science.gov (United States)

    Mu, Dashuai; Mu, Xin; Xu, Zhenxing; Du, Zongjun; Chen, Guanjun

    2015-12-01

    In this study, an efficient separation technology using Al2O3 nanoparticles (NPs) was developed for removing Bacillus subtilis from fermentation broth. The dosage of alumina nanoparticles used for separating B. subtilis increased during the culture process and remained stable in the stationary phase of the culture process. The pH of the culture-broth was also investigated for its effects on flocculation efficiency, and showed an acidic pH could enhance the flocculation efficiency. The attachment mechanisms of Al2O3 NPs to the B. subtilis surface were investigated, and the zeta potential analysis showed that Al2O3 NPs could attach to B. subtilis via electrostatic attachment. Finally, the metabolite content and the antibacterial effect of the fermentation supernatants were detected and did not significantly differ between alumina nanoparticle separation and centrifugation separation. Together, these results indicate a great potential for a highly efficient and economical method for removing B. subtilis from fermentation broth using alumina nanoparticles. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. A Structured VAR under Changing Monetary Policy

    DEFF Research Database (Denmark)

    Juselius, Katarina

    The empirical analysis is mainly concerned with the aggregate demand for money relation as part of a small macroeconomic system. Using the theory of cointegrated VAR models for I(2) data the long-run relationships in the data are first investigated, and the ML-estimates of the corresponding coint...... the effects of capital liberalization on the determination of money, income, prices, and interest rates in a small open economy...

  6. Effects of Bacillus subtilis var. natto products on symptoms caused by blood flow disturbance in female patients with lifestyle diseases

    Science.gov (United States)

    Hitosugi, Masahito; Hamada, Katsuo; Misaka, Kazutaka

    2015-01-01

    The fermented soybean product natto is a popular traditional food in Japan and is considered a health supplement. NKCP®, a natto-derived dietary food supplement whose main component is bacillopeptidase F, has antithrombotic, fibrinolytic, and blood pressure-lowering effects. We examined whether daily intake of NKCP® effectively improves subjective symptoms in patients with lifestyle diseases in this cross-over, double-blind study. Fermented soya extract with subtilisin NAT (nattokinase) as the main component was used as an active placebo. A 4-week course of NKCP® significantly decreased the visual analog scale (VAS) score for shoulder stiffness from 42.3 to 32.4 (P=0.009), the VAS score for low back pain from 25.5 to 18.8 (P=0.02), and the VAS score for coldness of the extremities from 33.1 to 25.7 (P=0.002). However, no significant difference was found in the VAS score for headache. After a 4-week course of active placebo, no significant changes in the VAS score were found for any symptoms. The significant improvement in the symptoms secondary to blood flow disturbance was caused by the improvement in blood flow by NKCP®. The use of dietary supplements based on the Japanese traditional food natto helps to relieve subjective symptoms for patients with lifestyle diseases receiving medical care. PMID:25653551

  7. Effects of Bacillus subtilis var. natto products on symptoms caused by blood flow disturbance in female patients with lifestyle diseases

    Directory of Open Access Journals (Sweden)

    Hitosugi M

    2015-01-01

    Full Text Available Masahito Hitosugi,1,2 Katsuo Hamada,2 Kazutaka Misaka2 1Department of Legal Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan; 2Department of Internal Medicine, Nagareyama Central Hospital, Nagareyama, Chiba, Japan Abstract: The fermented soybean product natto is a popular traditional food in Japan and is considered a health supplement. NKCP®, a natto-derived dietary food supplement whose main component is bacillopeptidase F, has antithrombotic, fibrinolytic, and blood pressure-lowering effects. We examined whether daily intake of NKCP® effectively improves subjective symptoms in patients with lifestyle diseases in this cross-over, double-blind study. Fermented soya extract with subtilisin NAT (nattokinase as the main component was used as an active placebo. A 4-week course of NKCP® significantly decreased the visual analog scale (VAS score for shoulder stiffness from 42.3 to 32.4 (P=0.009, the VAS score for low back pain from 25.5 to 18.8 (P=0.02, and the VAS score for coldness of the extremities from 33.1 to 25.7 (P=0.002. However, no significant difference was found in the VAS score for headache. After a 4-week course of active placebo, no significant changes in the VAS score were found for any symptoms. The significant improvement in the symptoms secondary to blood flow disturbance was caused by the improvement in blood flow by NKCP®. The use of dietary supplements based on the Japanese traditional food natto helps to relieve subjective symptoms for patients with lifestyle diseases receiving medical care. Keywords: bacillopeptidase F, Japanese traditional food, lifestyle disease, subjective symptom, supplement

  8. Oil and Security in Nigeria: The Niger Delta Crisis | Owolabi | Africa ...

    African Journals Online (AJOL)

    This paper examines oil and security in Nigeria, with special reference to the crisis-ravaged Niger Delta. Its focus on the Niger Delta and its festering crisis stems from that region's critical importance to Nigeria. As the nation's treasure base, the Niger Delta provides over 80 percent of government revenues, 95 percent of ...

  9. Screening of mutant strains producing phytase from A. niger by 60Co γ-ray irradiation

    International Nuclear Information System (INIS)

    Yang Pingping; Wang Yan; Tao Wenyi

    2004-01-01

    60 Co γ-ray was used to irradiate Aspergillus niger 447-92 for screening the mutant strain of producing phytase, and the effects of mutation induction were determined and analyzed. A mutant strain A. niger 496-1 with high level of phytase was selected, the phytase properties of A. niger 496-1 were analyzed

  10. Trade and inter-group relations in the lower Niger 1830-1960 | Ali ...

    African Journals Online (AJOL)

    This study focuses on trade and intergroup relations in the Lower Niger in the period 1830-1960. Trade constitutes an integral aspect of communal relationship in the Lower Niger region from 1830 to 1960. The objective of the study is to show how the people of the Lower Niger related with each other in trade and other ...

  11. 40 CFR 180.1111 - Bacillus subtilis GB03; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus subtilis GB03; exemption from... FOOD Exemptions From Tolerances § 180.1111 Bacillus subtilis GB03; exemption from the requirement of a tolerance. The biofungicide Bacillus subtilis GB03 is exempted from the requirement of a tolerance in or on...

  12. 40 CFR 180.1128 - Bacillus subtilis MBI 600; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus subtilis MBI 600; exemption... FOOD Exemptions From Tolerances § 180.1128 Bacillus subtilis MBI 600; exemption from the requirement of... biofungicide Bacillus subtilis MBI 600 in or on all food commodities, including residues resulting from post...

  13. Production of milk-clotting enzyme by Bacillus subtilis B1 from wheat ...

    African Journals Online (AJOL)

    Three strains, Bacillus subtilis B1, B. subtilis B18 and Bacillus thuringiensis B12, were screened from wheat bran to produce milk-clotting enzyme. Among them, B. subtilis B1 exhibited considerable milkclotting activity with low proteolytic activity. After response surface methodology optimization, milkclotting activity was ...

  14. Crystallization and preliminary X-ray diffraction analysis of YisP protein from Bacillus subtilis subsp. subtilis strain 168

    International Nuclear Information System (INIS)

    Hu, Yumei; Jia, Shiru; Ren, Feifei; Huang, Chun-Hsiang; Ko, Tzu-Ping; Mitchell, Douglas A.; Guo, Rey-Ting; Zheng, Yingying

    2012-01-01

    A bacteria biofilm formation involved enzyme, BsYisP, from Bacillus subtilis subsp. subtilis strain 168, was crystallized and diffracted to 1.92 Å. YisP is an enzyme involved in the pathway of biofilm formation in bacteria and is predicted to possess squalene synthase activity. A BlastP search using the YisP protein sequence from Bacillus subtilis subsp. subtilis strain 168 shows that it shares 23% identity with the dehydrosqualene synthase from Staphylococcus aureus. The YisP from B. subtilis 168 was expressed in Escherichia coli and the recombinant protein was purified and crystallized. The crystals, which belong to the orthorhombic space group P2 1 2 1 2 1 , with unit-cell parameters a = 43.966, b = 77.576, c = 91.378 Å, were obtained by the sitting-drop vapour-diffusion method and diffracted to 1.92 Å resolution. Structure determination using MAD and MIR methods is in progress

  15. Analytical and computational approaches to define the Aspergillus niger secretome

    Energy Technology Data Exchange (ETDEWEB)

    Tsang, Adrian; Butler, Gregory D.; Powlowski, Justin; Panisko, Ellen A.; Baker, Scott E.

    2009-03-01

    We used computational and mass spectrometric approaches to characterize the Aspergillus niger secretome. The 11,200 gene models predicted in the genome of A. niger strain ATCC 1015 were the data source for the analysis. Depending on the computational methods used, 691 to 881 proteins were predicted to be secreted proteins. We cultured A. niger in six different media and analyzed the extracellular proteins produced using mass spectrometry. A total of 222 proteins were identified, with 39 proteins expressed under all six conditions and 74 proteins expressed under only one condition. The secreted proteins identified by mass spectrometry were used to guide the correction of about 20 gene models. Additional analysis focused on extracellular enzymes of interest for biomass processing. Of the 63 glycoside hydrolases predicted to be capable of hydrolyzing cellulose, hemicellulose or pectin, 94% of the exo-acting enzymes and only 18% of the endo-acting enzymes were experimentally detected.

  16. Electrochemical monitoring of citric acid production by Aspergillus niger

    International Nuclear Information System (INIS)

    Kutyła-Olesiuk, Anna; Wawrzyniak, Urszula E.; Ciosek, Patrycja; Wróblewski, Wojciech

    2014-01-01

    Highlights: • Citric acid fermentation process (production) by Aspergillus niger. • Qualitative/quantitative monitoring of standard culture and culture infected with yeast. • Electronic tongue based on potentiometric and voltammetric sensors. • Evaluation of the progress and the correctness of the fermentation process. • The highest classification abilities of the hybrid electronic tongue. - Abstract: Hybrid electronic tongue was developed for the monitoring of citric acid production by Aspergillus niger. The system based on various potentiometric/voltammetric sensors and appropriate chemometric techniques provided correct qualitative and quantitative classification of the samples collected during standard Aspergillus niger culture and culture infected with yeast. The performance of the proposed approach was compared with the monitoring of the fermentation process carried out using classical methods. The results obtained proved, that the designed hybrid electronic tongue was able to evaluate the progress and correctness of the fermentation process

  17. Electrochemical monitoring of citric acid production by Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Kutyła-Olesiuk, Anna; Wawrzyniak, Urszula E.; Ciosek, Patrycja; Wróblewski, Wojciech, E-mail: wuwu@ch.pw.edu.pl

    2014-05-01

    Highlights: • Citric acid fermentation process (production) by Aspergillus niger. • Qualitative/quantitative monitoring of standard culture and culture infected with yeast. • Electronic tongue based on potentiometric and voltammetric sensors. • Evaluation of the progress and the correctness of the fermentation process. • The highest classification abilities of the hybrid electronic tongue. - Abstract: Hybrid electronic tongue was developed for the monitoring of citric acid production by Aspergillus niger. The system based on various potentiometric/voltammetric sensors and appropriate chemometric techniques provided correct qualitative and quantitative classification of the samples collected during standard Aspergillus niger culture and culture infected with yeast. The performance of the proposed approach was compared with the monitoring of the fermentation process carried out using classical methods. The results obtained proved, that the designed hybrid electronic tongue was able to evaluate the progress and correctness of the fermentation process.

  18. Phosphate solubilizing ability of two Arctic Aspergillus niger strains

    Directory of Open Access Journals (Sweden)

    Shiv Mohan Singh,

    2011-06-01

    Full Text Available Many filamentous fungi were isolated from the soils of Ny-Ålesund, Spitsbergen, Svalbard, and were screened in vitro for their phosphate solubilizing ability. Two strains of Aspergillus niger showed good tricalcium phosphate (TCP solubilizing ability in Pikovskaya's medium. The TCP solubilization index was calculated at varying levels of pH and temperatures. The ability of Aspergillus niger strain-1 to solubilize and release inorganic-P was 285 µg ml–1, while Aspergillus niger strain-2 solubilized 262 µg ml–1 from 0.5% TCP after seven days. This is the first report of TCP solubilization by Arctic strains that may serve as very good phosphate solubilizers in the form of biofertilizer.

  19. Reconstruction of the central carbon metabolism of Aspergillus niger

    DEFF Research Database (Denmark)

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

    2003-01-01

    The topology of central carbon metabolism of Aspergillus niger was identified and the metabolic network reconstructed, by integrating genomic, biochemical and physiological information available for this microorganism and other related fungi. The reconstructed network may serve as a valuable...... of metabolic fluxes using metabolite balancing. This framework was employed to perform an in silico characterisation of the phenotypic behaviour of A. niger grown on different carbon sources. The effects on growth of single reaction deletions were assessed and essential biochemical reactions were identified...... for different carbon sources. Furthermore, application of the stoichiometric model for assessing the metabolic capabilities of A. niger to produce metabolites was evaluated by using succinate production as a case study....

  20. Physiological characterisation of acuB deletion in Aspergillus niger

    DEFF Research Database (Denmark)

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

    2009-01-01

    The acuB gene of Aspergillus niger is an ortholog of facB in Aspergillus nidulans. Under carbon-repression conditions, facB is repressed, thereby preventing acetate metabolism when the repressing carbon source is present. Even though facB is reported to be repressed directly by CreA, it is believed...... that a basal level of FacB activity exists under glucose-repressive conditions. In the present study, the effect of deletion of acuB on the physiology of A. niger was assessed. Differences in organic acid and acetate production, enzyme activities and extracellular amino and non-amino organic acid production...... were determined under glucose-repressing and -derepressing conditions. Furthermore, consumption of alternative carbon sources (e.g. xylose, citrate, lactate and succinate) was investigated. It was shown that AcuB has pleiotropic effects on the physiology of A. niger. The results indicate that metabolic...

  1. The "Protests against Charlie Hebdo" in Niger: A Background Analysis

    Directory of Open Access Journals (Sweden)

    Jannik Schritt

    2015-01-01

    Full Text Available In many Muslim countries in West Africa and beyond, “protests against Charlie Hebdo” occurred when citizens went out on the streets following Friday prayers on 16 January 2015. However, only in Niger did these protests turn extremely violent. This report analyses the social, political and religious workings behind the protests in Niger. In doing so, it shows that the so-called “protests against Charlie Hebdo” are only superficially linked to the Muhammad cartoons by the French satirical magazine. Similarly violent protests have occurred in Niger – often in the town of Zinder – for quite different reasons and on different occasions in recent years. The report therefore argues against simplistic notions of religious fundamentalism and shows that the protests can be explained more appropriately in terms of politics and socio-economic exclusion.

  2. Fumonisin and Ochratoxin Production in Industrial Aspergillus niger Strains

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Larsen, Thomas Ostenfeld; Thrane, Ulf

    2011-01-01

    as safe). However, A. niger has the potential to produce two groups of potentially carcinogenic mycotoxins: fumonisins and ochratoxins. In this study all available industrial and many non-industrial strains of A. niger (180 strains) as well as 228 strains from 17 related black Aspergillus species were...... examined for mycotoxin production. None of the related 17 species of black Aspergilli produced fumonisins. Fumonisins (B(2), B(4), and B(6)) were detected in 81% of A. niger, and ochratoxin A in 17%, while 10% of the strains produced both mycotoxins. Among the industrial strains the same ratios were 83......%, 33% and 26% respectively. Some of the most frequently used strains in industry NRRL 337, 3112 and 3122 produced both toxins and several strains used for citric acid production were among the best producers of fumonisins in pure agar culture. Most strains used for other biotechnological processes also...

  3. Fast neutron radiation inactivation of Bacillus subtilis: Absorbed dose determination

    International Nuclear Information System (INIS)

    Song Lingli; Zheng Chun; Ai Zihui; Li Junjie; Dai Shaofeng

    2011-01-01

    In this paper, fast neutron inactivation effects of Bacillus subtilis were investigated with fission fast neutrons from CFBR-II reactor of INPC (Institute of Nuclear Physics and Chemistry) and mono-energetic neutrons from the Van de Graaff accelerator at Peking University. The method for determining the absorbed dose in the Bacillus subtilis suspension contained in test tubes is introduced. The absorbed dose, on account of its dependence on the volume and the form of confined state, was determined by combined experiments and Monte Carlo method. Using the calculation results of absorbed dose, the fast neutron inactivation effects on Bacillus subtilis were studied. The survival rates and absorbed dose curve was constructed. (authors)

  4. Construction of acetoin high-producing Bacillus subtilis strain

    Directory of Open Access Journals (Sweden)

    Yanjun Tian

    2016-07-01

    Full Text Available This paper describes the construction and selection of a high-producing mutant, Bacillus subtilis HB-32, with enhanced acetoin yield and productivity. The mutant was obtained by the protoplast fusion of a Bacillus subtilis mutant TH-49 (Val− producing acetoin and Bacillus licheniformis AD-30 producing α-acetolactate decarboxylase, with the fusogen polyethylene glycol and after the regeneration and selection, etc. of the fusant. The acetoin production reached 49.64 g/L, which is an increase of 61.8% compared to that of B. subtilis strain TH-49. Random amplified polymorphic DNA analysis was performed to determine the mutagenic and protoplast fusion effects and the genomic changes in the acetoin high-producing strain compared to the parent strains at the molecular level. The constructed strain was shown to be promising for large-scale acetoin production. Future studies should focus on the application of the mutant strain in practice.

  5. Ultrasensitivity of the Bacillus subtilis sporulation decision.

    Science.gov (United States)

    Narula, Jatin; Devi, Seram N; Fujita, Masaya; Igoshin, Oleg A

    2012-12-11

    Starving Bacillus subtilis cells execute a gene expression program resulting in the formation of stress-resistant spores. Sporulation master regulator, Spo0A, is activated by a phosphorelay and controls the expression of a multitude of genes, including the forespore-specific sigma factor σ(F) and the mother cell-specific sigma factor σ(E). Identification of the system-level mechanism of the sporulation decision is hindered by a lack of direct control over Spo0A activity. This limitation can be overcome by using a synthetic system in which Spo0A activation is controlled by inducing expression of phosphorelay kinase KinA. This induction results in a switch-like increase in the number of sporulating cells at a threshold of KinA. Using a combination of mathematical modeling and single-cell microscopy, we investigate the origin and physiological significance of this ultrasensitive threshold. The results indicate that the phosphorelay is unable to achieve a sufficiently fast and ultrasensitive response via its positive feedback architecture, suggesting that the sporulation decision is made downstream. In contrast, activation of σ(F) in the forespore and of σ(E) in the mother cell compartments occurs via a cascade of coherent feed-forward loops, and thereby can produce fast and ultrasensitive responses as a result of KinA induction. Unlike σ(F) activation, σ(E) activation in the mother cell compartment only occurs above the KinA threshold, resulting in completion of sporulation. Thus, ultrasensitive σ(E) activation explains the KinA threshold for sporulation induction. We therefore infer that under uncertain conditions, cells initiate sporulation but postpone making the sporulation decision to average stochastic fluctuations and to achieve a robust population response.

  6. Recombination-deficient mutants of Bacillus subtilis

    International Nuclear Information System (INIS)

    Sadaie, Y.; Kada, T.

    1976-01-01

    Two mutant strains of Bacillus subtilis Marburg, NIG43 and NIG45, were isolated. They showed high sensitivities to gamma rays, ultraviolet light (uv), and chemicals. Deficiencies in genetic recombination of these two mutants were shown by the experiments on their capacity in transformation, SPO2 transfection, and PBS1 phage transduction, as well as on their radiation and drug sensitivities and their Hcr + capacity for uv-exposed phage M2. Some of these characteristics were compared with those of the known strains possessing the recA1 or recB2 alleles. Mapping studies revealed that the mutation rec-43 of strain NIG43 lies in the region of chromosome replication origin. The order was purA dna-8132 rec-43. Another mutation, rec-45, of strain NIG45 was found to be tightly linked to recA1. The mutation rec-43 reduced mainly the frequency of PBS1 transduction. On the other hand, the mutation rec-45 reduced the frequency of recombination involved both in transformation and PBS1 tranduction. The mutation rec-43 of strain NIG43 is conditional, but rec-45 of strain NIG45 is not. The uv impairment in cellular survival of strain NIG43 was gradually reverted at higher salt or sucrose concentrations, suggesting cellular possession of a mutated gene product whose function is conditional. In contrast to several other recombination-deficient strains, SPO2 lysogens of strains NIG43 and NIG45 were not inducible, indicating involvement of rec-43 + or rec-45 + gene product in the development of SPO2 prophage to a vegetative form. The uv-induced deoxyribonucleic acid degradation in vegetative cells was higher in rec-43 and rec-45 strains

  7. Synoptic Lithostratigraphy of The Niger Delta

    International Nuclear Information System (INIS)

    Nwajide, C.S.

    2002-01-01

    The Tertiary Niger Delta is stratigraphically framed by the Dahomey, Anambra, Abakaliki, Afikpo and Calabar Flank basins. From the apex at Onitsha a fluvial plain splays southwards and translates progressively into a freshwater swamp, succeeded by a mangrove swamp belt. Along the coast is a strip of wave-washed barrier bars indented by large estuaries, fronted by submerged moth bars. Habitation in the delta is on levees, point bars, and barrier bars. These landforms provided the firm salients for buildings the ports that facilitated international trade from the pre-colonial times.There are four lithofacies-clean, pebbly, and muddy sandstones, and mudstones. Their subdivision, based on sedimentary structures, textures and fossil content yields twenty reservoir and seven nonreservoir classes. Their environments of deposition, identified using facies associations, fall into fluvial, wave-and tide-dominated, marginal, and shallow marine, with localised canyons incised into the delta front and filled with deeper marine facies.The reservoirs are composed of 70 90% quartz, 4 15% feldspar, and 3 13% clay matrix, with minor mica, bioclasts, carbonaceous debris, glauconite, and heavy minerals. Grain size varies from very fine to coarse and pebbly, implying the presence of sands of varying textural and compositional maturities. Silica, K-feldspar, and carbonates constitute the cements.Porosity in the reservoirs has remained about the same as at deposition due to low mechanical compaction occasioned by shallow burial. Meteoric water-flushed progradational sequence are characterised by cementation with quartz and kaolinite. In contrast, marine water-flushed transgressive sands show grain coating illite-smectite, chlorite and K-feldspar overgrowths

  8. Metabolic control analysis of Aspergillus niger L-arabinose catabolism

    DEFF Research Database (Denmark)

    de Groot, M.J.L.; Prathumpai, Wai; Visser, J.

    2005-01-01

    A mathematical model of the L-arabinose/D-xylose catabolic pathway of Aspergillus niger was constructed based on the kinetic properties of the enzymes. For this purpose L-arabinose reductase, L-arabitol dehydrogenase and D-xylose reductase were purified using dye-affinity chromatography...... aiming at either flux or metabolite level optimization of the L-arabinose catabolic pathway of A. niger. Faster L-arabinose utilization may enhance utilization of readily available organic waste containing hemicelluloses to be converted into industrially interesting metabolites or valuable enzymes...

  9. Production of extremophilic bacterial cellulase enzymes in aspergillus niger.

    Energy Technology Data Exchange (ETDEWEB)

    Gladden, John Michael

    2013-09-01

    Enzymes can be used to catalyze a myriad of chemical reactions and are a cornerstone in the biotechnology industry. Enzymes have a wide range of uses, ranging from medicine with the production of pharmaceuticals to energy were they are applied to biofuel production. However, it is difficult to produce large quantities of enzymes, especially if they are non-native to the production host. Fortunately, filamentous fungi, such as Aspergillus niger, are broadly used in industry and show great potential for use a heterologous enzyme production hosts. Here, we present work outlining an effort to engineer A. niger to produce thermophilic bacterial cellulases relevant to lignocellulosic biofuel production.

  10. Enhancement of Cellulase Production by Cellulomonas Fimi and Bacillus Subtilis

    International Nuclear Information System (INIS)

    Omer, A.M.

    2012-01-01

    Two bacterial strains identified as Cellulomonas fimi and Baciliius subtilus are cosidered as highly active cellulytic bacteria. Trials for maximizing the cellulolytic activites of the two strains were conducted. A maximum cellulase production was achieved at 1 and 1.5%carboxy methyl cellulose as carbon source, sodium nitrate and yeast as nitrogen source for Cellulomonas fimi and Bacillus subtilis, respectively. Incubation temprature at 30 and 45 degree C, ph at 6 and 7 achieved the highest activity of cellulase for Cellulomonas fimi and bacillus subtilis, respectively

  11. Sigma A recognition sites in the Bacillus subtilis genome

    DEFF Research Database (Denmark)

    Jarmer, Hanne Østergaard; Larsen, Thomas Schou; Krogh, Anders Stærmose

    2001-01-01

    A hidden Markov model of sigma (A) RNA polymerase cofactor recognition sites in Bacillus subtilis, containing either the common or the extended -10 motifs, has been constructed based on experimentally verified sigma (A) recognition sites. This work suggests that more information exists...... at the initiation site of transcription in both types of promoters than previously thought. When tested on the entire B. subtilis genome, the model predicts that approximately half of the sigma (A) recognition sites are of the extended type. Some of the response-regulator aspartate phosphatases were among...

  12. Antibiotic Stimulation of a Bacillus subtilis Migratory Response

    Science.gov (United States)

    Liu, Yongjin; Kyle, Steven

    2018-01-01

    ABSTRACT Competitive interactions between bacteria reveal physiological adaptations that benefit fitness. Bacillus subtilis is a Gram-positive species with several adaptive mechanisms for competition and environmental stress. Biofilm formation, sporulation, and motility are the outcomes of widespread changes in a population of B. subtilis. These changes emerge from complex, regulated pathways for adapting to external stresses, including competition from other species. To identify competition-specific functions, we cultured B. subtilis with multiple species of Streptomyces and observed altered patterns of growth for each organism. In particular, when plated on agar medium near Streptomyces venezuelae, B. subtilis initiates a robust and reproducible mobile response. To investigate the mechanistic basis for the interaction, we determined the type of motility used by B. subtilis and isolated inducing metabolites produced by S. venezuelae. Bacillus subtilis has three defined forms of motility: swimming, swarming, and sliding. Streptomyces venezuelae induced sliding motility specifically in our experiments. The inducing agents produced by S. venezuelae were identified as chloramphenicol and a brominated derivative at subinhibitory concentrations. Upon further characterization of the mobile response, our results demonstrated that subinhibitory concentrations of chloramphenicol, erythromycin, tetracycline, and spectinomycin all activate a sliding motility response by B. subtilis. Our data are consistent with sliding motility initiating under conditions of protein translation stress. This report underscores the importance of hormesis as an early warning system for potential bacterial competitors and antibiotic exposure. IMPORTANCE Antibiotic resistance is a major challenge for the effective treatment of infectious diseases. Identifying adaptive mechanisms that bacteria use to survive low levels of antibiotic stress is important for understanding pathways to

  13. Evolution of exploitative interactions during diversification in Bacillus subtilis biofilms

    DEFF Research Database (Denmark)

    Dragoš, Anna; Lakshmanan, Nivedha; Martin, Marivic

    2018-01-01

    variants. These variants can settle in alternative biofilm niches and develop new types of interactions that greatly influence population productivity. Here, we explore the evolutionary diversification of pellicle biofilms of the Gram positive, spore-forming bacterium Bacillus subtilis. We discover that......-similarly to other species-B. subtilis diversifies into distinct colony variants. These variants dramatically differ in biofilm formation abilities and expression of biofilm-related genes. In addition, using a quantitative approach, we reveal striking differences in surface complexity and hydrophobicity...

  14. Characterization of a bacteriocin-like substance produced from a novel isolated strain of Bacillus subtilis SLYY-3

    Science.gov (United States)

    Li, Junfeng; Li, Hongfang; Zhang, Yuanyuan; Duan, Xiaohui; Liu, Jie

    2014-12-01

    In the present research, the strain SLYY-3 was isolated from sediments of Jiaozhou Bay, Qingdao, China. The strain SLYY-3, which produced a bacteriocin-like substance (BLS), was characterized to be a strain of Bacillus subtillis by biochemical profiling and 16S rDNA sequence analysis. It is the first time to report that Bacillus subtilis from Jiaozhou Bay sediments could produce a BLS. The BLS of B. subtillis SLYY-3 exhibited strong inhibitory activity against gram-positive bacteria (including Staphylococcus aureus and B. subtillis) and some fungi (including Penicillium glaucum, Aspergillus niger and Aspergillus flavus). The antimicrobial activity was detected from culture in the exponential growth phase and reached its maximum when culture entered into stationary growth phase. It was thermo-tolerant even when being kept at 100°C for 60 min without losing any activity and stable over a wide pH range from 1.0 to 12.0 while being inactivated by proteolytic enzyme and trypsin, indicating the proteinaceous nature of the BLS. The BLS was purified by precipitation with hydrochloric acid (HCl) and gel filteration (Sephadex G-100). SDS-PAGE analysis of the extracellular peptides of SLYY-3 revealed a bacteriocin-like protein with a molecular mass of 66 kDa. Altogether, these characteristics indicate the potential of the BLS for food industry as a protection against pathogenic and spoilage microorganisms.

  15. 77 FR 73934 - Bacillus subtilis Strain QST 713 Variant Soil; Amendment to an Exemption From the Requirement of...

    Science.gov (United States)

    2012-12-12

    ... Bacillus subtilis Strain QST 713 To Include Residues of Bacillus subtilis Strain QST 713 Variant Soil... existing exemption from the requirement of a tolerance for residues of the Bacillus subtilis strain QST 713 in or on all food commodities by including residues of Bacillus subtilis strain QST 713 variant soil...

  16. A Generic Protocol for Intracellular Expression of Recombinant Proteins in Bacillus subtilis.

    Science.gov (United States)

    Phan, Trang; Huynh, Phuong; Truong, Tuom; Nguyen, Hoang

    2017-01-01

    Bacillus subtilis (B. subtilis) is a potential and attractive host for the production of recombinant proteins. Different expression systems for B. subtilis have been developed recently, and various target proteins have been recombinantly synthesized and purified using this host. In this chapter, we introduce a generic protocol to express a recombinant protein in B. subtilis. It includes protocols for (1) using our typical expression vector (plasmid pHT254) to introduce a target gene, (2) transformation of the target vector into B. subtilis, and (3) evaluation of the actual expression of a recombinant protein.

  17. Survival and infectivity of Sarcoptes scabiei var. canis and var. hominis.

    Science.gov (United States)

    Arlian, L G; Runyan, R A; Achar, S; Estes, S A

    1984-08-01

    Sarcoptes scabiei var. canis served as a suitable model for the study of S. scabiei var. hominis survival. S. scabiei var. canis and var. hominis mites were found to survive off the host for 24 to 36 hours at room conditions (21 degrees C and 40% to 80% relative humidity [RH]), and the canine variety survived 19 days at 10 degrees C and 97% RH. Female mites survived decidedly longer than male mites at comparable conditions. Generally, higher RH values and lower temperatures favored survival, whereas higher temperature and lower RH led to early death. Most canine scabies mites that were held off the host for 36 hours at 75% RH and 22 degrees to 24 degrees C remained infective and penetrated when returned to the host. Live mites of the human variety that were recovered from bed linen slept on by infested patients would also penetrate a host after being held off a host for 96 hours in alternating 12-hour periods of room conditions and refrigeration. Penetration required less than 30 minutes for all life stages of both varieties, and it was accomplished by a mite secretion that dissolved the host tissue. Dislodged mites, particularly those in close proximity to the source, can be a likely source of infestation.

  18. Cardenolide glycosides from Elaeodendron australe var. integrifolium.

    Science.gov (United States)

    Butler, Mark S; Towerzey, Leanne; Pham, Ngoc B; Hyde, Edward; Wadi, Sao Khemar; Guymer, Gordon P; Quinn, Ronald J

    2014-02-01

    Extracts from dried leaf and stems of Elaeodendron australe var. integrifolium (Celastraceae) collected in South East Queensland, Australia, were active in an assay that measured Ca(2+) driven expression of IL-2/luciferase designed to identify inhibitors of the ICRAC channel. Bioassay-guided isolation using C18 and polyamide column chromatography, HPLC (Phenyl and C18) and centrifugal partition chromatography (CPC) led to the isolation of digitoxigenin (1) and three cardenolide glycosides, glucoside 2, quinovoside 3 and the new natural product xyloside 4, as the active components with low nM activity in the reporter assay. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. VAR IPP-IPC Model Simulation

    Directory of Open Access Journals (Sweden)

    Juan P. Pérez Monsalve

    2014-12-01

    Full Text Available This work analyzed the relationship of the two main Price indicators in the Colombian economy, the IPP and the IPC. For this purpose, we identified the theory comprising both indexes to then develop a vector autoregressive model, which shows the reaction to shocks both in itself as in the other variable, whose impact continues propagating in the long term. Additionally, the work presents a simulation of the VAR model through the Monte Carlo method, verifying the coincidence in distributions of probability and volatility levels, as well as the existence correlation over time

  20. Case Study: Neglected Health Issues in Niger

    Directory of Open Access Journals (Sweden)

    Cameron Neylon

    2017-10-01

    Full Text Available The project “Problemes négligés du système de santé au Niger” focusses on a core set of often-neglected issues that nevertheless have an overall negative impact on health system effectiveness in Niger. For example, poor quality maternal health services result from challenges related to the midwifery profession and from pressures from addressing the effects of illegal termination of pregnancy. Overall health system governance is undermined by weak management of human resources and health information systems as well as problems related to decentralisation of health care provision and dependence on external funding for health projects. LASDEL applies a rapid assessment and qualitative research approach to working with patients and health care professionals to identify the scale and characteristics of these problems. The project goal is to develop an evidence base to support tackling these neglected issues. Développer des recherches sur les « problèmes négligés » dans la gouvernance de la santé, et sur cette base contribuer à des réformes des systèmes de santé permettant une meilleure qualité des soins pour les populations vulnérables. "Develop research on "neglected problems" in the provision of health systems, and through this work, contribute to health system reforms, that provide better quality of care for vulnerable populations." As can be seen above, many of these issues relate to reproductive health and more generally to health issues of disadvantaged groups. Some issues are neglected for political or social reasons meaning that they are not recognised or acknowledged and in some cases are criminalised. Therefore there are profound issues of participant privacy, protection and even safety for this project. Data sharing therefore requires thoughtful anonymisation and selection. The project group is Francophone with limited English language knowledge and the researchers and the context is largely in French. In common with

  1. Antioxidation, angiotensin converting enzyme inhibition activity, nattokinase, and antihypertension of Bacillus subtilis (natto)-fermented pigeon pea

    OpenAIRE

    Bao-Hong Lee; Yi-Syuan Lai; She-Ching Wu

    2015-01-01

    Because of the high incidence of cardiovascular diseases in Asian countries, traditional fermented foods from Asia have been increasingly investigated for antiatherosclerotic effects. This study investigated the production of nattokinase, a serine fibrinolytic enzyme, in pigeon pea by Bacillus subtilis fermentation. B. subtilis 14714, B. subtilis 14715, B. subtilis 14716, and B. subtilis 14718 were employed to produce nattokinase. The highest nattokinase activity in pigeon pea was obtained us...

  2. The impact of manganese on biofilm development of Bacillus subtilis

    NARCIS (Netherlands)

    Mhatre, Eisha; Troszok, Agnieszka; Gallegos-Monterrosa, Ramses; Lindstädt, Stefanie; Hölscher, Theresa; Kuipers, Oscar P.; Kovács, Ákos T.

    2016-01-01

    Bacterial biofilms are dynamic and structurally complex communities, involving cell-to-cell interactions. In recent years, various environmental signals were identified that induce the complex biofilm development of the Gram-positive bacterium Bacillus subtilis. These signaling molecules are often

  3. Enhanced biomass production study on probiotic Bacillus subtilis ...

    African Journals Online (AJOL)

    The culture conditions of lactose fermenting, spore forming probiotic Bacillus subtilis SK09 isolated from dairy effluent were optimized by response surface methodology to maximize the biomass production. The student's t-test of the Placket-Burman screening design revealed that the effects of pH, ammonium citrate and ...

  4. Characterization of a thermostable Bacillus subtilis β-amylase

    African Journals Online (AJOL)

    ... 70 0C respectively, and the thermal stability curve gave a maximum activity of 9.75 U at 70oC for 60 min of incubation. Bacillus subtilis â-amylase is valuable for maltose production, which can be hydrolyzed further by other groups of amylase for the production of high cassava glucose syrup used as sweeteners in the food ...

  5. PRODIGIOSIN INDUCES AUTOLYSINS IN ACTIVELY GROWN Bacillus subtilis CELLS

    Directory of Open Access Journals (Sweden)

    Tjasa eDanevcic

    2016-01-01

    Full Text Available Prodigiosin produced by marine bacterium Vibrio ruber DSM 14379 exhibits a potent antimicrobial activity against a broad range of Gram positive and Gram negative bacteria. The mechanism of prodigiosin antimicrobial action, however, is not known. In this work, the effect of prodigiosin on B. subtilis growth, cell membrane leakage, and induction of autolysins was studied. Treating B. subtilis with prodigiosin resulted in rapid decline of optical density and increased cell membrane leakage measured by β-galactosidase activity. Cell lysis was initiated immediately after treatment with prodigiosin in the middle exponential phase and was completed within two hours. Lytic activity of prodigiosin in mutant strains with impaired autolysin genes lytABCD decreased for 80 % compared to the wild-type strain, while in lytABCDEF mutant strain prodigiosin had no bacteriolytic but only bacteriostatic effect. Fast prodigiosin lytic activity on individual B. subtilis cells was confirmed by a modified comet assay. The results indicate that prodigiosin autolysin induction in B. subtilis is growth phase dependent.

  6. A part toolbox to tune genetic expression in Bacillus subtilis

    Science.gov (United States)

    Guiziou, Sarah; Sauveplane, Vincent; Chang, Hung-Ju; Clerté, Caroline; Declerck, Nathalie; Jules, Matthieu; Bonnet, Jerome

    2016-01-01

    Libraries of well-characterised components regulating gene expression levels are essential to many synthetic biology applications. While widely available for the Gram-negative model bacterium Escherichia coli, such libraries are lacking for the Gram-positive model Bacillus subtilis, a key organism for basic research and biotechnological applications. Here, we engineered a genetic toolbox comprising libraries of promoters, Ribosome Binding Sites (RBS), and protein degradation tags to precisely tune gene expression in B. subtilis. We first designed a modular Expression Operating Unit (EOU) facilitating parts assembly and modifications and providing a standard genetic context for gene circuits implementation. We then selected native, constitutive promoters of B. subtilis and efficient RBS sequences from which we engineered three promoters and three RBS sequence libraries exhibiting ∼14 000-fold dynamic range in gene expression levels. We also designed a collection of SsrA proteolysis tags of variable strength. Finally, by using fluorescence fluctuation methods coupled with two-photon microscopy, we quantified the absolute concentration of GFP in a subset of strains from the library. Our complete promoters and RBS sequences library comprising over 135 constructs enables tuning of GFP concentration over five orders of magnitude, from 0.05 to 700 μM. This toolbox of regulatory components will support many research and engineering applications in B. subtilis. PMID:27402159

  7. The transcriptionally active regions in the genome of Bacillus subtilis

    DEFF Research Database (Denmark)

    Rasmussen, Simon; Nielsen, Henrik Bjørn; Jarmer, Hanne Østergaard

    2009-01-01

    The majority of all genes have so far been identified and annotated systematically through in silico gene finding. Here we report the finding of 3662 strand-specific transcriptionally active regions (TARs) in the genome of Bacillus subtilis by the use of tiling arrays. We have measured the genome...

  8. Transformation of undomesticated strains of Bacillus subtilis by protoplast electroporation

    NARCIS (Netherlands)

    Romero, Diego; Perez-Garcia, Alejandro; Veening, Jan-Willem; de Vicente, Antonio; Kuipers, Oscar P.; de, Vicente A.

    A rapid method combining the use of protoplasts and electroporation was developed to transform recalcitrant wild strains of Bacillus subtilis. The method described here allows transformation with both replicative and integrative plasmids, as well as with chromosomal DNA, and provides a valuable tool

  9. Extracellular protease produced by Bacillus subtilis isolated from ...

    African Journals Online (AJOL)

    In a study to evaluate the microbiological safety of some paracetamol oral solutions sold in some Nigerian drug stores, 40.0% of the samples examined was contaminated with protease-producing Bacillus subtilis. The production of extracellular protease was induced by casein in the minimal medium and was found to be the ...

  10. Assembly properties of the Bacillus subtilis actin, MreB.

    Science.gov (United States)

    Mayer, Joshua A; Amann, Kurt J

    2009-02-01

    The bacterial actin MreB has been implicated in a variety of cellular roles including cell shape determination, cell wall synthesis, chromosome condensation and segregation, and the establishment and maintenance of cell polarity. Toward elucidating a clearer understanding of how MreB functions inside the bacterial cell, we investigated biochemically the polymerization of MreB from Bacillus subtilis. Light scattering and sedimentation assays revealed pH-, ionic-, cationic-, and temperature-dependent behavior. B. subtilis MreB polymerizes in the presence of millimolar divalent cations in a protein concentration-dependent manner. Polymerization is favored by decreasing pH and inhibited by monovalent salts and low temperatures. Although B. subtilis MreB binds and hydrolyzes both ATP and GTP, it does not require a bound nucleotide for assembly and polymerizes indistinguishably regardless of the nucleotide species bound, with a critical concentration of approximately 900 nM. A number of the presently reported properties of B. subtilis MreB differ significantly from those of T. maritima MreB1 (Bean and Amann [2008]: Biochemistry 47: 826-835), including the nucleotide requirements and temperature and ionic effects on polymerization state. These observations collectively suggest that additional factors interact with MreB to account for its complex dynamic behavior in cells.

  11. bmr3, a third multidrug transporter gene of Bacillus subtilis.

    OpenAIRE

    Ohki, R; Murata, M

    1997-01-01

    A third multidrug transporter gene named bmr3 was cloned from Bacillus subtilis. Although Bmr3 shows relatively low homology to Bmr and Blt, the substrate specificities of these three transporters overlap. Northern hybridization analysis showed that expression of the bmr3 gene was dependent on the growth phase.

  12. Genome engineering using a synthetic gene circuit in Bacillus subtilis.

    Science.gov (United States)

    Jeong, Da-Eun; Park, Seung-Hwan; Pan, Jae-Gu; Kim, Eui-Joong; Choi, Soo-Keun

    2015-03-31

    Genome engineering without leaving foreign DNA behind requires an efficient counter-selectable marker system. Here, we developed a genome engineering method in Bacillus subtilis using a synthetic gene circuit as a counter-selectable marker system. The system contained two repressible promoters (B. subtilis xylA (Pxyl) and spac (Pspac)) and two repressor genes (lacI and xylR). Pxyl-lacI was integrated into the B. subtilis genome with a target gene containing a desired mutation. The xylR and Pspac-chloramphenicol resistant genes (cat) were located on a helper plasmid. In the presence of xylose, repression of XylR by xylose induced LacI expression, the LacIs repressed the Pspac promoter and the cells become chloramphenicol sensitive. Thus, to survive in the presence of chloramphenicol, the cell must delete Pxyl-lacI by recombination between the wild-type and mutated target genes. The recombination leads to mutation of the target gene. The remaining helper plasmid was removed easily under the chloramphenicol absent condition. In this study, we showed base insertion, deletion and point mutation of the B. subtilis genome without leaving any foreign DNA behind. Additionally, we successfully deleted a 2-kb gene (amyE) and a 38-kb operon (ppsABCDE). This method will be useful to construct designer Bacillus strains for various industrial applications. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  13. Degradation of extracytoplasmic catalysts for protein folding in Bacillus subtilis

    NARCIS (Netherlands)

    Krishnappa, Laxmi; Monteferrante, Carmine G; Neef, Jolanda; Dreisbach, Annette; van Dijl, Jan Maarten

    The general protein secretion pathway of Bacillus subtilis has a high capacity for protein export from the cytoplasm, which is exploited in the biotechnological production of a wide range of enzymes. These exported proteins pass the membrane in an unfolded state, and accordingly, they have to fold

  14. Protein export in bacillus subtilis and escherichia coli

    NARCIS (Netherlands)

    Dijl, Jan Maarten van

    1990-01-01

    The export of heterologous proteins in Bacillus subtilis and Escherichia coli is often inefficient. Frequently observed problems are: 1) accumulation of the precursor form of the exported protein in the cytoplasm or in the membrane; 2), inefficient or incorrect processing of the precursor; 3),

  15. Effect Of Aspergillus Niger Biodegradation On The Nutriti0nal ...

    African Journals Online (AJOL)

    The effect of Aspergillus niger on the nutritional potential of cowpea seed hull after different physical treatments was investigated. The crude protein ranges from 14.11% to 15.07 and 16.71% in the untreated seed hull (UCH), soaked and boiled (SBCH) and soaked (SCH) respectively, before fungi degradation but after the ...

  16. Glucoamylase production by a newly isolated strain of Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Sinkar, V.P.; Lewis, N.F.

    1982-01-01

    Glucoamylase production by Aspergillus niger 57 was studied in complex and synthetic media under stationary vs. submerged conditions. Stationary cultivation resulted in significantly greater yields than did submerged culture. Crude enzyme activity was optimum at 60 degrees and pH 4.0.

  17. Utilization of Brewery Spent Grain Liquor by Aspergillus niger1

    Science.gov (United States)

    Hang, Y. D.; Splittstoesser, D. F.; Woodams, E. E.

    1975-01-01

    Aspergillus niger was found capable of rapidly converting about 97% of the sugar from brewery spent grain liquor to fungal mass. The yield of dry mycelium, based on the sugar consumed, was approximately 57%. This fungus produced 1.10% titratable acid calculated as citric acid and reduced the biochemical oxygen demand by 96%. PMID:1200633

  18. The occurrence of a phosphorylated glycosphingolipid in Aspergillus niger.

    Science.gov (United States)

    Brennan, P J; Roe, J

    1975-01-01

    A novel type of water-soluble phosphorylated glycosphingolipid was isolated from Aspergillus niger by a simple procedure involving precipitation, DEAE-cellulose chromatography and preparative t.l.c. Besides ceramide and phosphorus it contains inositol, galactose, mannose and small amounts of glucosamine. Images PLATE 1 PMID:1156383

  19. Gluconate formation and polyol metabolism in Aspergillus niger

    NARCIS (Netherlands)

    Witteveen, C.F.B.

    1993-01-01

    The capacity of A.niger to accumulate metabolites is remarkable. Under all conditions polyols accumulate in the cell and when mycelium in later developmental stages is considered, depending on the carbon source, aeration and external pH, polyols

  20. assessment of millennium development goal 7 in the niger delta ...

    African Journals Online (AJOL)

    user

    the largest in Africa and is second only to Russia in gas flaring [3]. The Niger ..... emission values of CO2, CH4 and N2O, and BC and GHGs from 1990 to .... Billion. This value consists of the cost of gas flared ..... Private Partnership. Washington ...

  1. Application in Down-hole Milling Operations In Niger Delta.

    African Journals Online (AJOL)

    ENGINEERS

    export terminals, 275 flow stations, 10 gas plants, 3 refineries and a massive natural ..... clear of the Niger Delta', adding that, 'The Chinese government by investing in stolen .... Development Agency (SMEDAN); to help boost the growth of both countries' ..... “The Rule of Oil: Petro-Politics and the Anatomy of an Insurgency”.

  2. Structures Deduced From Gravity Data In The Lower Niger Benue ...

    African Journals Online (AJOL)

    Based on a recent gravity data collected over the area, the Lower Niger and Lower Benue basins are interpreted to comprise five major structural zones. The locations, trends, extent and relationships between most previously known structures in the area are confirmed and detailed by the data. However, the structure ...

  3. Comparative study of Aspergillus niger and Penicillium sp. in the ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-06-14

    Jun 14, 2010 ... The comparative study of Aspergillus niger and Penicillium sp. in the biodegradation of automotive gas oil (AGO) and premium motor spirit (PMS) was carried out to ascertain the effectiveness of using these microorganisms in cleaning and restoring the ecosystem when polluted by petroleum products.

  4. Cytochemical Localization of Glucose Oxidase in Peroxisomes of Aspergillus niger

    NARCIS (Netherlands)

    Veenhuis, Marten; Dijken, Johannes Pieter van

    1980-01-01

    The subcellular localization of glucose oxidase (E.C. 1.1.3.4) in mycelia of Aspergillus niger has been investigated using cytochemical staining techniques. Mycelia from fermenter cultures, which produced gluconic acid from glucose, contained elevated levels of glucose oxidase and catalase. Both

  5. Lead immobilization by geological fluorapatite and fungus Aspergillus niger.

    Science.gov (United States)

    Li, Zhen; Wang, Fuwei; Bai, Tongshuo; Tao, Jinjin; Guo, Jieyun; Yang, Mengying; Wang, Shimei; Hu, Shuijin

    2016-12-15

    Phosphate solubilizing fungi have high ability to secrete organic acids. In this study, fungus Aspergillus niger and geological fluorapatite were applied in lead remediation in aqueous solution. Formation and morphology of the lead minerals, e.g., pyromorphite and lead oxalate, were investigated by SEM, XRD, and ATR-IR. The total quantity of organic acids reached the maximum at the sixth day, which improved the concentration of soluble P up to ∼370mg/L from ∼0.4mg/L. The organic acids, especially the oxalic acid, enhance the solubility of fluorapatite significantly. The stable fluoropyromorphite [Pb 5 (PO 4 ) 3 F] is precipitated with the elevated solubility of fluorapatite in the acidic environment. Furthermore, A. niger grows normally with the presence of lead cations. It is shown that >99% lead cations can be removed from the solution. However, immobilization caused by the precipitation of lead oxalate cannot be ignored if the fungus A. niger was cultured in the Pb solution. This study elucidates the mechanisms of lead immobilization by FAp and A. niger, and sheds its perspective in lead remediation, especially for high Pb concentration solution. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Enhanced citrate production through gene insertion in Aspergillus niger

    DEFF Research Database (Denmark)

    Jongh, Wian de; Nielsen, Jens

    2007-01-01

    The effect of inserting genes involved in the reductive branch of the tricarboxylic acid (TCA) cycle on citrate production by Aspergillus niger was evaluated. Several different genes were inserted individually and in combination, i.e. malate dehydrogenase (mdh2) from Saccharomyces cerevisiae, two...

  7. Characterization of four new antifungal yanuthones from Aspergillus niger

    DEFF Research Database (Denmark)

    Petersen, Lene Maj; Holm, Dorte Koefoed; Knudsen, Peter Boldsen

    2015-01-01

    Four new yanuthone analogs (1–4) were isolated from the filamentous fungus Aspergillus niger. The structures of the new compounds were elucidated on the basis of UHPLC-DAD-HRMS data and one-dimensional and two-dimensional NMR spectroscopy. Labeling studies with 13C8-6-methylsalicylic acid...

  8. Localization of Glucose Oxidase and Catalase Activities in Aspergillus niger

    NARCIS (Netherlands)

    Witteveen, Cor F.B.; Veenhuis, Marten; Visser, Jaap

    The subcellular localization of glucose oxidase (EC 1.1.3.4) in Aspergillus niger N400 (CBS 120.49) was investigated by (immuno)cytochemical methods. By these methods, the bulk of the enzyme was found to be localized in the cell wall. In addition, four different catalases (EC 1.11.1.6) were

  9. Production of Aspergillus niger beta-mannosidase in Pichia pastoris

    Czech Academy of Sciences Publication Activity Database

    Fliedrová, Barbora; Gerstorferová, Daniela; Křen, Vladimír; Weignerová, Lenka

    2012-01-01

    Roč. 85, č. 2 (2012), s. 159-164 ISSN 1046-5928 R&D Projects: GA ČR GAP207/10/0321; GA ČR GD305/09/H008; GA MŠk(CZ) 7E11011 Keywords : Beta-mannosidase * Aspergillus niger * Cloning Subject RIV: CE - Biochemistry Impact factor: 1.429, year: 2012

  10. Evolution of the Niger Delta, present dynamics and the future ...

    African Journals Online (AJOL)

    Evolution of the Niger Delta is closely linked to the geodynamics related to the separation of the African and South American continents and the tectonics of the formation of the Benue Trough. Tectonic activities, climate and eustasy are the major factors responsible for transgression and regression through the entrant point ...

  11. Ibani (Niger Delta) Traditional Religion and Social Morality | Jaja ...

    African Journals Online (AJOL)

    The Ibani is of the Ijo extraction in the Niger Delta of Nigeria. The belief in a Supreme Being called Tamuno but also on multitude of deities because of the environment in which they live. They believe that these deities perform social functions that stabilize society. Ibani cosmology revolve round the tripod – God, deities and ...

  12. Ethnic Minority Problems in the Niger Delta | Quaker-Dokubo ...

    African Journals Online (AJOL)

    As a conceptual background typical types of minorities and typical sources of minority conflict are outlined. A historical overview is given of the problems Niger Delta minorities have been experiencing. Their grievances and demands are highlighted, and the responses of different Nigerian governments are discussed.

  13. Recombinant bacterial hemoglobin alters metabolism of Aspergillus niger

    DEFF Research Database (Denmark)

    Hofmann, Gerald; Diano, Audrey; Nielsen, Jens

    2009-01-01

    , the fungus will produce various by-products like organic acids and polyols. In order to circumvent this problem we here study the effects of the expression of a bacterial hemoglobin protein on the metabolism of A. niger. We integrated the vgb gene from Vitreoscilla sp. into the genome at the pyrA locus...

  14. Quality characterization of Niger seed oil ( Guizotia Abyssinica Cass ...

    African Journals Online (AJOL)

    In the present investigation, an attempt has been made to find out cholesterol and total free fatty acid content in Niger seed oil which is the most available edible oil in Ethiopia. Acid value, peroxide value, saponification value and cholesterol content were determined. The analysis performed using Liebermann-Burchard ...

  15. cellulase and pectinase production potentials of aspergillus niger

    African Journals Online (AJOL)

    Prof Oyeleke

    Production of pectinase and cellulase by Aspergillus niger from corn cob was examined. ... organism was screened for enzymatic activity using Carboxyl Methyl ... preparation of denim fabrics in textile industries, ... exploitation of cellulase is its high cost of production ... catabolite repression influence economics of cellulase.

  16. Effects Of Solid State Fermentation By Aspergillus niger and ...

    African Journals Online (AJOL)

    fermentation and incubated for O (control), 4,8 and 10 days to evaluate the changes in crude protein (CP), crude fibre (CF), neutral detergent fibre (NDF), acid detergent fibre (ADF) and hemicellulose (HEMI). Ten days after inoculation of Cassava peel meal (CPM) with Aspergillus niger, the crude protein increased from ...

  17. Improving cellulase production by Aspergillus niger using adaptive evolution

    NARCIS (Netherlands)

    Patyshakuliyeva, Aleksandrina; Arentshorst, Mark; Allijn, Iris E; Ram, Arthur F J; de Vries, Ronald P; Gelber, Isabelle Benoit

    OBJECTIVES: To evaluate the potential of adaptive evolution as a tool in generating strains with an improved production of plant biomass degrading enzymes. RESULTS: An Aspergillus niger cellulase mutant was obtained by adaptive evolution. Physiological properties of this mutant revealed a five times

  18. Traditional wrestling in Niger: between state voluntarism and ...

    African Journals Online (AJOL)

    Traditional wrestling occupies pride of place in Niger, compared to other sports and cultural activities. Interest in traditional wrestling is widespread among Nigériens from all walks of life: young men, adults, senior citizens, young women, mature women, adult men, handicapped persons, prisoners, peasant farmers, civil ...

  19. Induction, purification and characterisation of arabinases produced by Aspergillus niger.

    NARCIS (Netherlands)

    Veen, van de P.; Flipphi, M.J.A.; Voragen, A.G.J.; Visser, J.

    1991-01-01

    The induction of arabinases in Aspergillus niger N400 was studied on different simple and complex carbon sources. Sugar beet pulp was found to be an inducer of three arabinan degrading enzymes (alpha-L-arabinofuranosidase A, alpha-L-arabinofuranosidase B and endoarabinase). These enzymes were

  20. Environmental Degradation in Oil Producing Areas of Niger Delta ...

    African Journals Online (AJOL)

    Due to oil exploration and other human activities in the Niger Delta region, there is evidence of environmental degradation all over the area (Oronto, 1998). Environmental degradation is occasioned by consistent flow of industrial waste, oil spills, gas flares, fire disaster, acid rain, flooding erosion, etc., which has led to the ...

  1. Acid Rain in Niger Delta Region: Implication on Water Resources ...

    African Journals Online (AJOL)

    This research focused on the effect of acid rain on the water quality of the Niger Delta region of Nigeria. Three hundred water samples were collected: 100 water samples from rain, 100 from open wells and 100 from rivers. The water samples were analysed using the paired t-test and multiple correlation analysis to ascertain ...

  2. Assessing soil erosion risk in the Tillabery landscape, Niger ...

    African Journals Online (AJOL)

    The results show that soil erosion output scenarios predict greater soil erosion in the study area from 2070 onwards. They suggest that human disturbance and topographic factors are the main impact factors in the affected areas. Key words: Tillabéry landscape (Niger), sheet and rill erosion modelling, data mining.

  3. Adolescent Sexual and Reproductive Health in the Niger Delta ...

    African Journals Online (AJOL)

    There has been an increasing awareness of the need to pay special focus on the adolescent and their sexual and reproductive health. This article reviews the sexual and reproductive health of adolescents in the Niger Delta region (NDR) of Nigeria. The objective is to bring to focus these important issues in the region.

  4. Mannitol is required for stress tolerance in Aspergillus niger conidiospores

    NARCIS (Netherlands)

    Ruijter, G.J.G.; Bax, M.; Patel, H.; Flitter, S.J.; Vondervoort, van de P.J.I.; Vries, de R.P.; Kuyk, van P.A.; Visser, J.

    2003-01-01

    D-Mannitol is the predominant carbon compound in conidiospores of the filamentous fungus Aspergillus niger and makes up 10 to 15% of the dry weight. A number of physiological functions have been ascribed to mannitol, including serving as a reserve carbon source, as an antioxidant, and to store

  5. Actual Uranium Exploration and Mining Activities in Niger

    International Nuclear Information System (INIS)

    Kache, Mamane

    2014-01-01

    Conclusion: Since the Fukushima nuclear power plant accident in 2011, many mining companies are not interested in uranium. It leads to the decrease in uranium spot price and the delay of IMOURAREN Project. Only, 47 exploration licenses for 12 mining companies are now valid in Niger.

  6. Lipids of marine origin: the rudderfish (Centrolophus niger)

    CSIR Research Space (South Africa)

    De Koning, AJ

    2006-01-01

    Full Text Available Muscle of rudderfish (centrolophus niger), or black ruff, a rare mesopelagic fish caught in the South Atlantic, was found to contain 19.3% total lipids. The major part of the lipids (~70%) was unusual in not yielding glycerol but non...

  7. Sawaba's rebellion in Niger (1964-1965) : narrative and meaning

    NARCIS (Netherlands)

    Walraven, van K.

    2003-01-01

    One of the least-studied revolts in postcolonial Africa, the invasion of Niger in 1964 by guerrillas of the outlawed Sawaba party, was a dismal failure and culminated in a failed attempt on the life of President Diori in the spring of 1965. Personal aspirations for higher education, access to jobs

  8. Pectinases of Aspergillus niger : a molecular and biochemical characterisation

    NARCIS (Netherlands)

    Parenicová, L.

    2000-01-01

    The major topics of this thesis are the microfilamentous fungus Aspergillus niger and the pectinases a group of extracellular enzymes. Many 'products' of this species hold the GRAS (Generally Regarded As Safe) status and thus pectinases find a broad range of

  9. An annotated list of Fishes from the Niger Delta

    NARCIS (Netherlands)

    Boeseman, M.

    1963-01-01

    At the end of November 1960, the Leiden Museum received an interesting collection of animals, mostly fishes, from the Niger delta. All specimens were collected by Mr. H. J. G. Beets, at the time employed by Shell B.P. — Delta Investigations, during the period May to August 1960, and in the region

  10. Amnesty in the Niger Delta: vertical movement towards self ...

    African Journals Online (AJOL)

    ... promises of infrastructure development in the region and direct payments of oil revenues to host-communities. This paper seeks to examine the recent developments vis-à-vis the government's amnesty initiative to determine if this policy has bridged the gap in the longstanding selfdetermination demands of the Niger Delta ...

  11. Flood vulnerability: Impending danger in Sabon-Gari Minna, Niger ...

    African Journals Online (AJOL)

    This study examines the vulnerability of buildings to flooding and the danger posed at Sabo Gari area of Minna, Niger State. Sabon-Gari which is one of the 22 neighborhoods found in Minna is a highly populated area as people who cannot afford to stay in the low density areas (Government Reserve Area - G.R.A) move to ...

  12. aranthus cruentus L) in the Niger Delta Region of Nigeria

    African Journals Online (AJOL)

    ABSTRACT. Experiments were conducted in 1987 and 1988 to study the response of Amaranthus cruentus L. to flooded soils at Ekpoma, situated in-the Niger Delta Region of Nigeria. The objective of this study was to examine the effect of flooding on yield of A. Céiieiìtus. The study revealed that the negative response of the ...

  13. The Economic Dimensions of the Niger Delta Ethnic Conflicts ...

    African Journals Online (AJOL)

    This paper presents a descriptive analysis of the remote and immediate causes of the armed ethnic conflicts in the Niger Delta in Nigeria and attempts to proffer a strategic approach rather than the use of brute force in managing the conflicts. The study revealed that the underlying cause of the conflict is the prolonged ...

  14. Towards an Ethics of the Environment in the Niger Delta

    African Journals Online (AJOL)

    FIRST LADY

    and the responsibility for both human and non-human components of nature are indeed wholly ... intend to do in this work therefore is to evolve an ethics of the Niger Delta environment which ... African Research Review Vol. 4(3a) July, 2010.

  15. Fuzzy Failure Probability of Transmission Pipelines in the Niger ...

    African Journals Online (AJOL)

    We undertake the apportioning of failure possibility on twelve identified third party activities contributory to failure of transmission pipelines in the Niger Delta region of Nigeria, using the concept of fuzzy possibility scores. Expert elicitation technique generates linguistic variables that are transformed using fuzzy set theory ...

  16. Metabolic control analysis of Aspergillus niger L-arabinose catabolism

    NARCIS (Netherlands)

    Groot, de M.J.L.; Prathumpai, W.; Visser, J.; Ruijter, G.J.G.

    2005-01-01

    A mathematical model of the L-arabinose/D-xylose catabolic pathway of Aspergillus niger was constructed based on the kinetic properties of the enzymes. For this purpose L-arabinose reductase, L-arabitol dehydrogenase and D-xylose reductase were purified using dye-affinity chromatography, and their

  17. Extracellular acid protease from Aspergillus niger I1: purification and ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-09-15

    Sep 15, 2009 ... A new strain of Aspergillus niger producing acid protease was isolated and identified by universal primers NL1 and .... Media were autoclaved at 120°C for 20 min. ... molecular weight calibration kit as markers consisting of bovine ... then removed by washing the gel three times with 100 mM ..... New York.

  18. Mantle electrical conductivity profile of Niger delta region

    Indian Academy of Sciences (India)

    The mantle electrical conductivity-depth profile of the Niger delta region in Nigeria has been determined using solar quiet day ionospheric current (Sq).The magnetometer data obtained in 2010 from geomagnetic stations installed in Lagos by magnetic dataset (MAGDAS) in 2008 and data from magnetometers installed in ...

  19. The Niger Delta: State Repression and Violence Nexus

    African Journals Online (AJOL)

    crosdel emuedo

    2005-02-19

    Feb 19, 2005 ... This explains its concern only with unimpeded access to crude oil at very cheap ... The people of the Niger Delta on the other hand, places premium on the concept of human ... going amnesty, over 123 hostages were taken.

  20. Optimization of chloroxylenol degradation by Aspergillus niger using ...

    African Journals Online (AJOL)

    Chloroxylenol is a very toxic phenolic derivative and it represents potential hazard towards human health and to the environment. Aspergillus niger, local isolate, is an efficient fungus to degrade 99.72% of 2 mg/L of chloroxylenol after 7 days of fermentation. It also has a high capacity to degrade 91.83% of higher ...

  1. Comparative study of Aspergillus niger and Penicillium sp. in the ...

    African Journals Online (AJOL)

    The comparative study of Aspergillus niger and Penicillium sp. in the biodegradation of automotive gas oil (AGO) and premium motor spirit (PMS) was carried out to ascertain the effectiveness of using these microorganisms in cleaning and restoring the ecosystem when polluted by petroleum products. These fungi were ...

  2. Evaluation of xylanases from Aspergillus niger and Trichoderma sp ...

    African Journals Online (AJOL)

    Despite being present in relatively low amounts, pentosans and hemicelluloses play an important role in dough rheology and bread properties. The aim of this work is to understand how the xylanases from Aspergillus niger and Trichoderma sp. influence dough rheology, such as elasticity, extensibility, strength and stability.

  3. Optimization for cellulase production by Aspergillus niger using saw ...

    African Journals Online (AJOL)

    Cellulases are a group of hydrolytic enzymes and are capable of degrading lignocellulosic materials. Cellulases have wide range of applications. This work focuses on factors relevant for improvement of enzymatic hydrolysis of saw dust by using Aspergillus niger. Different cultural conditions were examined to assess their ...

  4. The search for environmental justice in the Niger Delta and ...

    African Journals Online (AJOL)

    Right from the beginning Man has been given the privilege by his Creator to tender the earth and take dominion over his environment. But for the impoverished people of the Niger Delta region, the mainstay of Nigeria's oil wealth, the situation is ironically abysmal. The region has been the scene of protest, sometimes ...

  5. What are pregnant women in a rural Niger Delta community's ...

    African Journals Online (AJOL)

    To date, studies have sought cause and effect and have neglected the opinion of the people about what they perceive to be problematic and what they believe constitutes satisfactory maternity service provision. An exploratory qualitative study was carried out to identify pregnant women in a rural Niger Delta community's ...

  6. Phonology and Morphology of Mambay (Niger-Congo, Adamawa)

    NARCIS (Netherlands)

    Anonby, Erik John

    2008-01-01

    Mambay is an Adamawa (Niger-Congo) language spoken by 15,000 people in Chad and Cameroon. The study opens with historical and linguistic background. A phonological inventory of the language is then presented and distribution patterns are examined. Some striking phenomena include a profoundly

  7. Enhancing stakeholder participation in the Niger Delta region: the ...

    African Journals Online (AJOL)

    Nigeria's indigenous people, found in the Niger Delta area, have for many years experienced developmental challenges associated with oil exploration. The region has been perennially engulfed in various forms of agitation pertaining to self-government and resource control. Over the years, attempts to solve these ...

  8. Niger institute focuses on financial accountability | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    28 avr. 2016 ... ... of its budgeting and reporting systems, and in staff morale. It plans further efforts to improve internal communications and achieve greater visibility. Read the story of change, Renewing financial management systems: Institut National de la Recherche Agronomique du Niger (PDF, 95 KB, in French only) ...

  9. Quercetin - A Flavonoid Compound from Sarcopyramis bodinieri var ...

    African Journals Online (AJOL)

    DAPI staining and PARP SDS-PAGE tests showed 60 μM quercetin could induce potential apoptotic activity in HepG2 liver cancer cells. Conclusion: Quercetin was the major cytotoxicity constituent in S. bodinieri var. delicate. Keywords: Apoptotic activity, Quercetin, Sarcopyramis bodinieri var. delicate, HepG2 liver cancer ...

  10. Growth and provenance variation of Pinus caribaea var ...

    African Journals Online (AJOL)

    CAMCORE has visited 33 populations of Pinus caribaea var. hondurensis in Belize, Guatemala, Honduras, El Salvador, Nicaragua, and Quintana Roo, Mexico. Seed collections have been made in 29 provenances from 1, 325 mother trees. A total of 21 provenances and sources of Pinus caribaea var. hondurensis were ...

  11. Larvicidal Activity of Isodon japonicus var. glaucocalyx (Maxim ...

    African Journals Online (AJOL)

    HP

    Purpose: To determine the larvicidal activity of the essential oil derived from Isodon japonicus var. ... Methods: The essential oil of I. japonicus var. glaucocalyx aerial parts was obtained by ..... µg/mL; G. silvatica leaves, LC50 = 117.9 µg/mL.

  12. ESTIMASI NILAI VaR PORTOFOLIO MENGGUNAKAN FUNGSI ARCHIMEDEAN COPULA

    Directory of Open Access Journals (Sweden)

    AULIA ATIKA PRAWIBTA SUHARTO

    2017-01-01

    Full Text Available Value at Risk explains the magnitude of the worst losses occurred in financial products investments with a certain level of confidence and time interval. The purpose of this study is to estimate the VaR of portfolio using Archimedean Copula family. The methods for calculating the VaR are as follows: (1 calculating the stock return; (2 calculating descriptive statistics of return; (3 checking for the nature of autocorrelation and heteroscedasticity effects on stock return data; (4 checking for the presence of extreme value by using Pareto tail; (5 estimating the parameters of Achimedean Copula family; (6 conducting simulations of Archimedean Copula; (7 estimating the value of the stock portfolio VaR. This study uses the closing price of TLKM and GGRM. At 90% the VaR obtained using Clayton, Gumbel, Frank copulas are 0.9562%, 1.0189%, 0.9827% respectively. At 95% the VaR obtained using Clayton, Gumbel, Frank copulas are 1.2930%, 1.2522%, 1.3152% respectively. At 99% the VaR obtained using Clayton, Gumbel, Frank copulas are 2.0327%, 1.9164%, is 1.8678% respectively. In conclusion estimation of VaR using Clayton copula yields the highest VaR.

  13. Een nieuwe naam voor Arenaria serpyllifolia L. var. macrocarpa Lloyd

    NARCIS (Netherlands)

    Gutermann, W.; Mennema, J.

    1983-01-01

    The name Arenaria serpyllifoiia L. var. macrocarpa Lloyd is illegitimate, because of the existence of the earlier non-synonymous A. serpyllifolia0 macrocarpa Godron. As on the level of variety no other name is available, we call the taxon A renaria serpylli/olia L. var. Iloydn (Jord.) Gutermann et

  14. Inhibition of Cell Differentiation in Bacillus subtilis by Pseudomonas protegens

    Science.gov (United States)

    Powers, Matthew J.; Sanabria-Valentín, Edgardo; Bowers, Albert A.

    2015-01-01

    ABSTRACT Interspecies interactions have been described for numerous bacterial systems, leading to the identification of chemical compounds that impact bacterial physiology and differentiation for processes such as biofilm formation. Here, we identified soil microbes that inhibit biofilm formation and sporulation in the common soil bacterium Bacillus subtilis. We did so by creating a reporter strain that fluoresces when the transcription of a biofilm-specific gene is repressed. Using this reporter in a coculture screen, we identified Pseudomonas putida and Pseudomonas protegens as bacteria that secrete compounds that inhibit biofilm gene expression in B. subtilis. The active compound produced by P. protegens was identified as the antibiotic and antifungal molecule 2,4-diacetylphloroglucinol (DAPG). Colonies of B. subtilis grown adjacent to a DAPG-producing P. protegens strain had altered colony morphologies relative to B. subtilis colonies grown next to a DAPG-null P. protegens strain (phlD strain). Using a subinhibitory concentration of purified DAPG in a pellicle assay, we saw that biofilm-specific gene transcription was delayed relative to transcription in untreated samples. These transcriptional changes also corresponded to phenotypic alterations: both biofilm biomass and spore formation were reduced in B. subtilis liquid cultures treated with subinhibitory concentrations of DAPG. Our results add DAPG to the growing list of antibiotics that impact bacterial development and physiology at subinhibitory concentrations. These findings also demonstrate the utility of using coculture as a means to uncover chemically mediated interspecies interactions between bacteria. IMPORTANCE Biofilms are communities of bacteria adhered to surfaces by an extracellular matrix; such biofilms can have important effects in both clinical and agricultural settings. To identify chemical compounds that inhibited biofilm formation, we used a fluorescent reporter to screen for bacteria that

  15. Coupled hydrologic and hydraulic modeling of Upper Niger River Basin

    Science.gov (United States)

    Fleischmann, Ayan; Siqueira, Vinícius; Paris, Adrien; Collischonn, Walter; Paiva, Rodrigo; Gossett, Marielle; Pontes, Paulo; Calmant, Stephane; Biancamaria, Sylvain; Crétaux, Jean-François; Tanimoune, Bachir

    2017-04-01

    The Upper Niger Basin is located in Western Africa, flowing from Guinea Highlands towards the Sahel region. In this area lies the seasonally inundated Niger Inland Delta, which supports important environmental services such as habitats for wildlife, climate and flood regulation, as well as large fishery and agricultural areas. In this study, we present the application of MGB-IPH large scale hydrologic and hydrodynamic model for the Upper Niger Basin, totaling c.a. 650,000 km2 and set up until the city of Niamey in Niger. The model couples hydrological vertical balance and runoff generation with hydrodynamic flood wave propagation, by allowing infiltration from floodplains into soil column as well as representing backwater effects and floodplain storage throughout flat areas such as the Inland Delta. The model is forced with TRMM 3B42 daily precipitation and Climate Research Unit (CRU) climatology for the period 2000-2010, and was calibrated against in-situ discharge gauges and validated with in-situ water level, remotely sensed estimations of flooded areas (classification of MODIS imagery) and satellite altimetry (JASON-2 mission). Model results show good predictions for calibrated daily discharge and validated water level and altimetry at stations both upstream and downstream of the delta (Nash-Sutcliffe Efficiency>0.7 for all stations), as well as for flooded areas within the delta region (ENS=0.5; r2=0.8), allowing a good representation of flooding dynamics basinwide and simulation of flooding behavior of both perennial (e.g., Niger main stem) and ephemeral rivers (e.g., Niger Red Flood tributaries in Sahel). Coupling between hydrology and hydrodynamic processes indicates an important feedback between floodplain and soil water storage that allows high evapotranspiration rates even after the flood passage around the inner delta area. Also, representation of water retention in floodplain channels and distributaries in the inner delta (e.g., Diaka river

  16. VaR Methodology Application for Banking Currency Portfolios

    Directory of Open Access Journals (Sweden)

    Daniel Armeanu

    2007-02-01

    Full Text Available VaR has become the standard measure that financial analysts use to quantify market risk. VaR measures can have many applications, such as in risk management, to evaluate the performance of risk takers and for regulatory requirements, and hence it is very important to develop methodologies that provide accurate estimates. In particular, the Basel Committee on Banking Supervision at the Bank for International Settlements imposes to financial institutions such as banks and investment firms to meet capital requirements based on VaR estimates. In this paper we determine VaR for a banking currency portfolio and respect rules of National Bank of Romania regarding VaR report.

  17. BIOMASS PRODUCTION AND FORMULATION OF Bacillus subtilis FOR BIOLOGICAL CONTROL

    Directory of Open Access Journals (Sweden)

    Amran Muis

    2016-10-01

    Full Text Available Bacillus subtilis is a widespread bacterium found in soil, water, and air. It controls the growth of certain harmful bacteria and fungi, presumably by competing for nutrients, growth sites on plants, and by directly colonizing and attaching to fungal pathogens. When applied to seeds, it colonizes the developing root system of the plants and continues to live on the root system and provides protection throughout the growing season. The study on biomass production and formulation of B. subtilis for biological control was conducted in the laboratory of Department of Plant Pathology, College of Agriculture, University of the Philippines Los Baños (UPLB-CA, College, Laguna from May to July 2005. The objective of the study was to determine the optimum pH and a good carbon source for biomass production of B. subtilis and to develop a seed treatment formulation of B. subtilis as biological control agent. Results showed that the optimum pH for growth of B. subtilis was pH 6 (1.85 x 109 cfu/ml. In laboratory tests for biomass production using cassava flour, corn flour, rice flour, and brown sugar as carbon sources, it grew best in brown sugar plus yeast extract medium (6.8 x 108 cfu ml-1 in sterile distilled water and 7.8 x 108 cfu ml-1 in coconut water. In test for bacterial biomass carriers, talc proved to be the best in terms of number of bacteria recovered from the seeds (3.98 x 105 cfu seed-1.

  18. Genetic Competence Drives Genome Diversity in Bacillus subtilis

    Science.gov (United States)

    Chevreux, Bastien; Serra, Cláudia R; Schyns, Ghislain; Henriques, Adriano O

    2018-01-01

    Abstract Prokaryote genomes are the result of a dynamic flux of genes, with increases achieved via horizontal gene transfer and reductions occurring through gene loss. The ecological and selective forces that drive this genomic flexibility vary across species. Bacillus subtilis is a naturally competent bacterium that occupies various environments, including plant-associated, soil, and marine niches, and the gut of both invertebrates and vertebrates. Here, we quantify the genomic diversity of B. subtilis and infer the genome dynamics that explain the high genetic and phenotypic diversity observed. Phylogenomic and comparative genomic analyses of 42 B. subtilis genomes uncover a remarkable genome diversity that translates into a core genome of 1,659 genes and an asymptotic pangenome growth rate of 57 new genes per new genome added. This diversity is due to a large proportion of low-frequency genes that are acquired from closely related species. We find no gene-loss bias among wild isolates, which explains why the cloud genome, 43% of the species pangenome, represents only a small proportion of each genome. We show that B. subtilis can acquire xenologous copies of core genes that propagate laterally among strains within a niche. While not excluding the contributions of other mechanisms, our results strongly suggest a process of gene acquisition that is largely driven by competence, where the long-term maintenance of acquired genes depends on local and global fitness effects. This competence-driven genomic diversity provides B. subtilis with its generalist character, enabling it to occupy a wide range of ecological niches and cycle through them. PMID:29272410

  19. Heterologous expression of antigenic peptides in Bacillus subtilis biofilms.

    Science.gov (United States)

    Vogt, Cédric M; Schraner, Elisabeth M; Aguilar, Claudio; Eichwald, Catherine

    2016-08-11

    Numerous strategies have been developed for the display of heterologous proteins in the surface of live bacterial carriers, which can be used as vaccines, immune-modulators, cancer therapy or bioremediation. Bacterial biofilms have emerged as an interesting approach for the expression of proteins of interest. Bacillus subtilis is a well-described, endospore-forming organism that is able to form biofilms and also used as a probiotic, thus making it a suitable candidate for the display of heterologous proteins within the biofilm. Here, we describe the use of TasA, an important structural component of the biofilms formed by B. subtilis, as a genetic tool for the display of heterologous proteins. We first engineered the fusion protein TasA-mCherry and showed that was widely deployed within the B. subtilis biofilms. A significant enhancement of the expression of TasA-mCherry within the biofilm was obtained when depleting both tasA and sinR genes. We subsequently engineered fusion proteins of TasA to antigenic peptides of the E. granulosus parasite, paramyosin and tropomyosin. Our results show that the antigens were well expressed within the biofilm as denoted by macrostructure complementation and by the detection of the fusion protein in both immunoblot and immunohistochemistry. In addition, we show that the recombinant endospores of B. subtilis preserve their biophysical and morphological properties. In this work we provide strong evidence pointing that TasA is a suitable candidate for the display of heterologous peptides, such as antigens, cytokines, enzymes or antibodies, in the B. subtilis biofilms. Finally, our data portray that the recombinant endospores preserve their morphological and biophysical properties and could be an excellent tool to facilitate the transport and the administration.

  20. Mechanisms of Action of Probiotics based on Bacillus subtilis

    Directory of Open Access Journals (Sweden)

    A.V. Savustyanenko

    2016-04-01

    Full Text Available The bacterium B.subtilis is one of the most promi­sing probiotics studied in recent decades. Mechanisms of its probiotic action are associated with the synthesis of antimicrobial agents, increasing of non-specific and specific immunity, stimulation of growth of normal microflora of the intestine and the releasing of digestive enzymes. B.subtilis releases ribosomally synthesized peptides, non-ribosomally synthesized peptides and non-peptide substances with a broad spectrum of antimicrobial activity covering Gram-positive, Gram-negative bacteria, viruses and fungi. Resistance to these antimicrobial agents is rare. Enhancement of non-specific immunity is associated with macrophage activation and the release of pro-inflammatory cytokines from them, increasing of barrier function of the intestinal mucosa, releasing of vitamins and amino acids (including essential ones. Enhancement of specific immunity manifests by activation of T- and B-lymphocytes and the release from the latter of immunoglobulins — IgG and IgA. B.subtilis stimulates the growth of normal intestinal flora, in particular, bacteria of the genus Lactobacillus and Bifidobacterium. Furthermore, probiotic increases the diversity of intestinal microflora. Probiotic secretes all major digestive enzymes to the intestinal lumen: amylases, lipases, proteases, pectinases and cellulases. In addition to digestion, these enzymes destroy antinutritional factors and allergenic substances contained in the food. These mechanisms of action make reasonable the use of B.subtilis in the combination therapy to treat intestinal infections; prevention of respiratory infections during the cold season; prevention of antibiotic-associated diarrhea; for the correction of food digestion and movement impairments of various origin (errors in the diet, changes in the diet, diseases of the gastrointestinal tract, disorders of the autonomic nervous system, etc.. B.subtilis does not usually cause side effects. This

  1. Dimethylglycine provides salt and temperature stress protection to Bacillus subtilis.

    Science.gov (United States)

    Bashir, Abdallah; Hoffmann, Tamara; Smits, Sander H J; Bremer, Erhard

    2014-05-01

    Glycine betaine is a potent osmotic and thermal stress protectant of many microorganisms. Its synthesis from glycine results in the formation of the intermediates monomethylglycine (sarcosine) and dimethylglycine (DMG), and these compounds are also produced when it is catabolized. Bacillus subtilis does not produce sarcosine or DMG, and it cannot metabolize these compounds. Here we have studied the potential of sarcosine and DMG to protect B. subtilis against osmotic, heat, and cold stress. Sarcosine, a compatible solute that possesses considerable protein-stabilizing properties, did not serve as a stress protectant of B. subtilis. DMG, on the other hand, proved to be only moderately effective as an osmotic stress protectant, but it exhibited good heat stress-relieving and excellent cold stress-relieving properties. DMG is imported into B. subtilis cells primarily under osmotic and temperature stress conditions via OpuA, a member of the ABC family of transporters. Ligand-binding studies with the extracellular solute receptor (OpuAC) of the OpuA system showed that OpuAC possesses a moderate affinity for DMG, with a Kd value of approximate 172 μM; its Kd for glycine betaine is about 26 μM. Docking studies using the crystal structures of the OpuAC protein with the sulfur analog of DMG, dimethylsulfonioacetate, as a template suggest a model of how the DMG molecule can be stably accommodated within the aromatic cage of the OpuAC ligand-binding pocket. Collectively, our data show that the ability to acquire DMG from exogenous sources under stressful environmental conditions helps the B. subtilis cell to cope with growth-restricting osmotic and temperature challenges.

  2. Fumonisin and Ochratoxin Production in Industrial Aspergillus niger Strains

    Science.gov (United States)

    Frisvad, Jens C.; Larsen, Thomas O.; Thrane, Ulf; Meijer, Martin; Varga, Janos; Samson, Robert A.; Nielsen, Kristian F.

    2011-01-01

    Aspergillus niger is perhaps the most important fungus used in biotechnology, and is also one of the most commonly encountered fungi contaminating foods and feedstuffs, and occurring in soil and indoor environments. Many of its industrial applications have been given GRAS status (generally regarded as safe). However, A. niger has the potential to produce two groups of potentially carcinogenic mycotoxins: fumonisins and ochratoxins. In this study all available industrial and many non-industrial strains of A. niger (180 strains) as well as 228 strains from 17 related black Aspergillus species were examined for mycotoxin production. None of the related 17 species of black Aspergilli produced fumonisins. Fumonisins (B2, B4, and B6) were detected in 81% of A. niger, and ochratoxin A in 17%, while 10% of the strains produced both mycotoxins. Among the industrial strains the same ratios were 83%, 33% and 26% respectively. Some of the most frequently used strains in industry NRRL 337, 3112 and 3122 produced both toxins and several strains used for citric acid production were among the best producers of fumonisins in pure agar culture. Most strains used for other biotechnological processes also produced fumonisins. Strains optimized through random mutagenesis usually maintained their mycotoxin production capability. Toxigenic strains were also able to produce the toxins on media suggested for citric acid production with most of the toxins found in the biomass, thereby questioning the use of the remaining biomass as animal feed. In conclusion it is recommended to use strains of A. niger with inactive or inactivated gene clusters for fumonisins and ochratoxins, or to choose isolates for biotechnological uses in related non-toxigenic species such as A. tubingensis, A. brasiliensis, A vadensis or A. acidus, which neither produce fumonisins nor ochratoxins. PMID:21853139

  3. Nigeria. Petroleum, pollution and poverty in the Niger Delta

    International Nuclear Information System (INIS)

    2009-06-01

    The oil industry has operated in the Niger Delta in Nigeria for more than half a century - bringing almost no benefit to the people living there. Instead, widespread and unchecked human rights violations have pushed many people deeper into poverty and deprivation, fuelled conflict and led to a pervasive sense of powerlessness and frustration. This multidimensional crisis is driven by many factors - abuses committed by the security forces and militant groups, extensive pollution of land and water, corruption, serious corporate bad practice and government neglect. Nigeria: Petroleum, pollution and poverty in the Niger Delta focuses on one dimension of the crisis: the impact of pollution and environmental damage caused by the oil industry on the human rights of those living in the Niger Delta. Many people in the oil-producing areas of the delta rely on fisheries, subsistence agriculture and associated processing industries for their livelihood. Decades of pollution and environmental damage have resulted in violations of the right to an adequate standard of living - including food and water - violations of the right to gain a living through work, and violations of the right to health. The report examines who is responsible for this situation in a context where multinational oil companies have been operating for decades. It highlights how companies take advantage of the weak regulatory systems that characterize many poor countries, and how the poorest people are often the most vulnerable to exploitation. The people of the Niger Delta have seen their human rights undermined by oil companies that their government can not - or will not - hold to account. They have been systematically denied access to information about how oil exploration and production will affect them, and are repeatedly denied access to justice. The Niger Delta provides a stark case study of the lack of accountability of a government to the people, and of multinational companies' almost total lack of

  4. Co-production of surfactin and a novel bacteriocin by Bacillus subtilis subsp. subtilis H4 isolated from bikalga, an African alkaline Hibiscus sabdariffa seed fermented condiment

    DEFF Research Database (Denmark)

    Compaore, C. S.; Nielsen, Dennis S.; Ouoba, L. I. I.

    2013-01-01

    inhibited in the agar spot assay while only Gram-positive pathogens were inhibited in the agar well diffusion assay. Cell free supernatants (CFS) of pure cultures of 3 B. subtilis subsp. subtilis (G2, H4 and F1) strains inhibited growth of Listeria monocytogenes, Micrococcus luteus, Staphylococcus aureus...

  5. Somatic Embryogenesis in Olive (Olea europaea L. subsp. europaea var. sativa and var. sylvestris).

    Science.gov (United States)

    Rugini, Eddo; Silvestri, Cristian

    2016-01-01

    Protocols for olive somatic embryogenesis from zygotic embryos and mature tissues have been described for both Olea europaea sub. europaea var. sativa and var. sylvestris. Immature zygotic embryos (no more than 75 days old), used after fruit collection or stored at 12-14 °C for 2-3 months, are the best responsive explants and very slightly genotype dependent, and one single protocol can be effective for a wide range of genotypes. On the contrary, protocols for mature zygotic embryos and for mature tissue of cultivars are often genotype specific, so that they may require many adjustments according to genotypes. The use of thidiazuron and cefotaxime seems to be an important trigger for induction phase particularly for tissues derived from cultivars. Up to now, however, the application of this technique for large-scale propagation is hampered also by the low rate of embryo germination; it proves nonetheless very useful for genetic improvement.

  6. Delice(Olea europea var. oleaster L.) ile zeytin (Olea europea var.sativa) arasında anatomik ve palinojik ayrıcalıklar (The Anatomic And Palynological Differences Between Olea europea var. oleaster L. AND Olea europea var.sativa)

    OpenAIRE

    Kaya, Zafer

    1991-01-01

    Delice(Olea europea var. oleaster L.) ile zeytin (Olea europea var.sativa) arasında anatomik ve palinojik ayrıcalıklar (The Anatomic And Palynological Differences Between Olea europea var. oleaster L. AND Olea europea var.sativa)

  7. Chromosome behaviour in Rhoeo spathacea var. variegata.

    Science.gov (United States)

    Lin, Y J

    1980-01-01

    Rhoeo spathacea var. variegata is unusual in that its twelve chromosomes are arranged in a ring at meiosis. The order of the chromosomes has been established, and each chromosome arm has been designated a letter in accordance with the segmental interchange theory. Chromosomes are often irregularly orientated at metaphase I. Chromosomes at anaphase I are generally distributed equally (6-6, 58.75%) although not necessarily balanced. Due to adjacent distribution, 7-5 distribution at anaphase I was frequently observed (24.17%), and due to lagging, 6-1-5 and 5-2-5 distributions were also observed (10.83% and 3.33% respectively). Three types of abnormal distribution, 8-4, 7-1-4 and 6-2-4 were observed very infrequently (2.92% total), and their possible origins are discussed. Irregularities, such as adjacent distribution and lagging, undoubtedly reduce the fertility of the plant because of the resulting unbalanced gametes.

  8. 1D-VAR Retrieval Using Superchannels

    Science.gov (United States)

    Liu, Xu; Zhou, Daniel; Larar, Allen; Smith, William L.; Schluessel, Peter; Mango, Stephen; SaintGermain, Karen

    2008-01-01

    Since modern ultra-spectral remote sensors have thousands of channels, it is difficult to include all of them in a 1D-var retrieval system. We will describe a physical inversion algorithm, which includes all available channels for the atmospheric temperature, moisture, cloud, and surface parameter retrievals. Both the forward model and the inversion algorithm compress the channel radiances into super channels. These super channels are obtained by projecting the radiance spectra onto a set of pre-calculated eigenvectors. The forward model provides both super channel properties and jacobian in EOF space directly. For ultra-spectral sensors such as Infrared Atmospheric Sounding Interferometer (IASI) and the NPOESS Airborne Sounder Testbed Interferometer (NAST), a compression ratio of more than 80 can be achieved, leading to a significant reduction in computations involved in an inversion process. Results will be shown applying the algorithm to real IASI and NAST data.

  9. Advances and prospects of Bacillus subtilis cellular factories: From rational design to industrial applications.

    Science.gov (United States)

    Gu, Yang; Xu, Xianhao; Wu, Yaokang; Niu, Tengfei; Liu, Yanfeng; Li, Jianghua; Du, Guocheng; Liu, Long

    2018-05-15

    Bacillus subtilis is the most characterized gram-positive bacterium that has significant attributes, such as growing well on cheap carbon sources, possessing clear inherited backgrounds, having mature genetic manipulation methods, and exhibiting robustness in large-scale fermentations. Till date, B. subtilis has been identified as attractive hosts for the production of recombinant proteins and chemicals. By applying various systems and synthetic biology tools, the productivity features of B. subtilis can be thoroughly analyzed and further optimized via metabolic engineering. In the present review, we discussed why B. subtilis is the primary organisms used for metabolic engineering and industrial applications. Additionally, we summarized the recent advances in systems and synthetic biology, engineering strategies for improving cellular performances, and metabolic engineering applications of B. subtilis. In particular, we proposed emerging opportunities and essential strategies to enable the successful development of B. subtilis as microbial cell factories. Copyright © 2018. Published by Elsevier Inc.

  10. Tryptophan provision by dietary supplementation of a Bacillus subtilis mutant strain in piglets

    DEFF Research Database (Denmark)

    Torres-Pitarch, A; Nielsen, B.; Canibe, Nuria

    2015-01-01

    Supplementing Bacillus (B.) subtilis mutants selected to overproduce a specific amino acid (AA) may be an alternative method to provide essential AA in pig diets. Two experiments on a B. subtilis strain selected to overproduce Trp were conducted using 8-kg pigs fed Trp-deficient diets for 20 d. B....... subtilis were supplied in a low or high dose in Experiments 1 and 2, respectively. The Trp-deficient diet (0.15 SID Trp:Lys) reduced (p subtilis strain was not able...... to counterbalance the Trp deficiency in any of the two experiments. No effect of B. subtilis supplementation to piglet diets was observed on the plasma AA profile. In conclusion, this mutant strain of B. subtilis was not able to compensate a Trp deficiency in the tested doses....

  11. Pitfalls in VAR based return decompositions: A clarification

    DEFF Research Database (Denmark)

    Engsted, Tom; Pedersen, Thomas Quistgaard; Tanggaard, Carsten

    in their analysis is not "cashflow news" but "inter- est rate news" which should not be zero. Consequently, in contrast to what Chen and Zhao claim, their decomposition does not serve as a valid caution against VAR based decompositions. Second, we point out that in order for VAR based decompositions to be valid......Based on Chen and Zhao's (2009) criticism of VAR based return de- compositions, we explain in detail the various limitations and pitfalls involved in such decompositions. First, we show that Chen and Zhao's interpretation of their excess bond return decomposition is wrong: the residual component...

  12. Generation of multiple cell types in Bacillus subtilis.

    Science.gov (United States)

    Lopez, Daniel; Vlamakis, Hera; Kolter, Roberto

    2009-01-01

    Bacillus subtilis is a Gram-positive bacterium that is well known for its ability to differentiate into metabolically inactive spores that are highly resistant to environmental stresses. In fact, populations of genetically identical B. subtilis comprise numerous distinct cell types. In addition to spores, cells can become genetically competent, motile, produce extracellular matrix or degradative enzymes, or secrete toxins that allow them to cannibalize their neighbors. Many of the cell fates listed above appear to be mutually exclusive. In this review, we discuss how individual cells within a population control their gene expression to ensure that proper regulation of differentiation occurs. These different cell fates are regulated by an intricate network that relies primarily on the activity of three major transcriptional regulators: Spo0A, DegU, and ComK. While individual cells must choose distinct cell fates, the population as a whole exhibits a spectrum of phenotypes whose diversity may increase fitness.

  13. Study of UV-mutagenesis in Bacillus subtilis

    International Nuclear Information System (INIS)

    Lotareva, O.V.; Filippov, V.D.

    1974-01-01

    The sensitivity of Bac. subtilis to the inactivating and mutagenic effects of UV-mutants has been determined: uvr, which does not extract pyrimidine dimers from damaged DNA; recsub(x), which exhibits a reduced activity of ATP-dependent DNAase; poll, which is devoid of DNA polymerase, and wild strains (DT). The sensitivity of these strains to the inactivating effects of UV rays increases in the order: DT<= recsub(x) << uvr < poll, and UV mutability in the order: DT = rec(sub(x) < poll<< uvr. A comparison of UV mutagenesis in Bac. subtilis and E. coli suggests the hypothesis that the mechanisms of UV mutation formation are similar in these two organisms. (author)

  14. Study of UV-induced mutagenesis in Bacillus subtilis

    International Nuclear Information System (INIS)

    Filippov, V.D.; Lotareva, O.V.

    1978-01-01

    The mechanism of UV-induced mutagenesis was studied in Bacillus subtilis departing from the assumption that a lower yield of UV-induced mutations should be found in mutants deficient in the recombination if production of mutations is coupled with the recombination process. Three recombination-deficient strains were used: two (recA and recF) with defects in different recombination pathways and the third (recB) has a block at a stage common for both of them. UV light induced reversions to prototrophy in recB cells and did not in recA and recF strains. Direct mutations, which confer to the cell additional growth requirements, were induced by UV light in recA and recF mutants. It is concluded that UV-induced mutagenesis in B subtilis is independent of the two known recombination mechanisms

  15. Sensitivity of thermally treated Bacillus subtilis spores to subsequent irradiation

    International Nuclear Information System (INIS)

    Mostafa, S.A.; El-Zawahry, Y.A.; Awny, N.M.

    1986-01-01

    B. subtilis spores exposed to thermal treatment at 70 or 80 0 C for 1 hr were more sensitive to subsequent radiation exposure than non-heated spores. Deactivation of previously heated spores by increasing dose of 0-radiation followed an exponential function while, for non-heated spores a shoulder followed by exponential deactivation was noticed. Combined heat-radiation treatment exhibited a synergistic effect on spore deactivation at low irradiation doses, while at high irradiation doses, the effect was more or less additive. Added values of spore injury was higher for B. subtilis spores that received heat and radiation separately than the observed injury for spores that received combined treatment (heat followed by radiation). Results of spore deactivation and injury due to heat followed by radiation treatment are discussed in comparison to those of spores that received radiation-heat sequence

  16. Biodegradation of furfural by Bacillus subtilis strain DS3.

    Science.gov (United States)

    Zheng, Dan; Bao, Jianguo; Lu, Jueming; Lv, Quanxi

    2015-07-01

    An aerobic bacterial strain DS3, capable of growing on furfural as sole carbon source, was isolated from actived sludge of wastewater treatment plant in a diosgenin factory after enrichment. Based on morphological physiological tests as well as 16SrDNA sequence and Biolog analyses it was identified as Bacillus subtilis. The study revealed that strain DS3 utilized furfural, as analyzed by high-performance liquid chromatography (HPLC). Under following conditions: pH 8.0, temperature 35 degrees C, 150 rpm and 10% inoculum, strain DS3 showed 31.2% furfural degradation. Furthermore, DS3 strain was found to tolerate furfural concentration as high as 6000 mg(-1). The ability of Bacillus subtilis strain DS3 to degrade furfural has been demonstrated for the first time in the present study.

  17. Production, regulation and transportation of bacillibactin in bacillus subtilis

    International Nuclear Information System (INIS)

    Raza, W.; Hussain, Q.; Shen, Q.

    2012-01-01

    Bacillus subtilis produces a catecholate type siderophore 'Bacillibactin'. This review focuses on the non-ribosomal synthesis, transport and regulation of bacillibactin. Bacillibactin biosynthetic operon contains five genes (dhbACEBF). The uptake of bacillibactin requires the FeuABC transporter, inner-membrane permease, FepDG and YusV ATPase and an esterase encoding gene, besA and while export required YmfE major facilitator super-family (MFS)-type transporter. Fur is the major iron-controlled transcriptional regulator in B. subtilis, which acts as an iron-dependent repressor of the dhb operon in vivo while an iron-independent repressor in vitro. Knowledge of the Fur regulon will be useful in interpreting other global analysis of transcriptional responses. (author)

  18. Effect of Bacillus subtilis microecological probiotics on livestock breeding

    Directory of Open Access Journals (Sweden)

    Xiaohui ZHOU

    2016-10-01

    Full Text Available As a kind of green and healthy microecologics, Bacillus subtilis could balance the intestinal flora, promote the nutrient absorption and enhance immunity. Microecologics is one of the ideal antibiotics alternative, which are effective in preventing and treating animal disease and promoting the growth and development of the animal. Because of its advantages, such as no toxin side effect and no residual or drug-resistant, microecologics has been used in livestock breeding widely. Here, we concluded the characteristics and mechanism of Bacillus subtilis,elaborated application of microecologics on livestock breeding, discussed its problems and suggested its solved methods. In the end, the future of microecologics was expected in order to provide a reference for subsequent livestock breeding.

  19. [Molecular cloning and expression of Nattokinase gene in Bacillus subtilis].

    Science.gov (United States)

    Liu, B Y; Song, H Y

    2002-05-01

    In order to characterize biochemically the nattokinase,the nucleotide sequence of the nattokinase gene was amplified from the chromosomal DNA of B.subtilis (natto) by PCR. The expression plasmid pBL NK was constructed and was used to transform Bacillus subtilis containing a chromosomal deletion in its subtilisin gene. The supernatant of the culture was collected after 15 h culture. The target proteins were identified by SDS-PAGE. Nattokinase was purified by a method including ultrafiltration, Sephacryl S-100 gel filtration and S-Sepharose ion-exchange chromatography, and 100 mg of purified nattokinase was obtained from one liter of culture. The purity of the protein and the specific activity were 95% and 12 000 u/mg (compared to tPA), respectively.

  20. Characterization of high hydrostatic pressure-injured Bacillus subtilis cells.

    Science.gov (United States)

    Inaoka, Takashi; Kimura, Keitarou; Morimatsu, Kazuya; Yamamoto, Kazutaka

    2017-06-01

    High hydrostatic pressure (HHP) affects various cellular processes. Using a sporulation-deficient Bacillus subtilis strain, we characterized the properties of vegetative cells subjected to HHP. When stationary-phase cells were exposed to 250 MPa of HHP for 10 min at 25 °C, approximately 50% of cells were viable, although they exhibited a prolonged growth lag. The HHP-injured cells autolyzed in the presence of NaCl or KCl (at concentrations ≥100 mM). Superoxide dismutase slightly protected the viability of HHP-treated cells, whereas vegetative catalases had no effect. Thus, unlike HHP-injured Escherichia coli, oxidative stress only slightly affected vegetative B. subtilis subjected to HHP.

  1. Enhanced hydrocarbon biodegradation by a newly isolated bacillus subtilis strain

    International Nuclear Information System (INIS)

    Christova, N.; Tuleva, B.; Nikolova-Damyanova, B.

    2004-01-01

    The relation between hydrocarbon degradation and biosurfactant (rhamnolipid) production by a new bacillus subtilis 22BN strain was investigated. The strain was isolated for its capacity to utilize n-hexadecane and naphthalene and at the same time to produce surface-active compound at high concentrations (1.5 - 2.0 g l -1 ). Biosurfactant production was detected by surface tension lowering and emulsifying activity. The strain is a good degrader of both hydrocarbons used with degradability of 98.3 ± 1% and 75 ± 2% for n-hexadecane and naphthalene, respectively. Measurement of cell hydrophobicity showed that the combination of slightly soluble substrate and rhamnolipid developed higher hydrophobicity correlated with increased utilization of both hydrocarbon substrates. To our knowledge, this is the first report of bacillus subtilis strain that degrades hydrophobic compounds and at the same time produces rhamnolipid biosurfactant. (orig.)

  2. Enhanced secretion of natto phytase by Bacillus subtilis.

    Science.gov (United States)

    Tsuji, Shogo; Tanaka, Kosei; Takenaka, Shinji; Yoshida, Ken-ichi

    2015-01-01

    Phytases comprise a group of phosphatases that trim inorganic phosphates from phytic acid (IP6). In this study, we aimed to achieve the efficient secretion of phytase by Bacillus subtilis. B. subtilis laboratory standard strain 168 and its derivatives exhibit no phytase activity, whereas a natto starter secretes phytase actively. The natto phytase gene was cloned into strain RIK1285, a protease-defective derivative of 168, to construct a random library of its N-terminal fusions with 173 different signal peptides (SPs) identified in the 168 genome. The library was screened to assess the efficiency of phytase secretion based on clear zones around colonies on plates, which appeared when IP6 was hydrolyzed. The pbp SP enhanced the secretion of the natto phytase most efficiently, i.e. twice that of the original SP. Thus, the secreted natto phytase was purified and found to remove up to 3 phosphates from IP6.

  3. Biotransformation of Progesterone by the Ascomycete Aspergillus niger N402.

    Science.gov (United States)

    Savinova, O S; Solyev, P N; Vasina, D V; Tyazhelova, T V; Fedorova, T V; Savinova, T S

    2018-01-01

    The ability of the ascomycete Aspergillus niger N402 to transform exogenous progesterone was investigated. We found that this strain has steroid-hydroxylating activity and can introduce a hydroxyl group into the progesterone molecule mainly at positions C11(α) and C21 with predominant formation of 21-hydroxyprogesterone (deoxycortone). In addition, formation of 6β,11α-dihydroxyprogesterone was also observed. Studying the effects of the growth medium composition and temperature on progesterone conversion by A. niger N402 showed that the most intense accumulation of 21-hydroxyprogesterone occurred in minimal synthetic medium at 28°C. Increasing the cultivation temperature to 37°C resulted in almost complete inhibition of the hydroxylase activity in the minimal medium. In the complete medium, a similar increase in temperature inhibited 11α-hydroxylase activity and completely suppressed 6β-hydroxylase activity, but it produced no effect on 21-hydroxylating activity.

  4. Production and qualification of transglucosidase from Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Benson, C.P.; Kelly, C.T.; Fogarty, W.M.

    1982-08-01

    The production of transglucosidase by Aspergillus niger was examined in batch culture with thin-layer chromatography (t.l.c.). Corn steep liquor was used as the nitrogen source and the activities obtained with four different carbon sources were examiend both qualitatively and quantitatively. Prompted by the non-quantitative nature of the t.l.c. assay technique, a quantiative transglucosidase assay procedure was developed subsequently. This was based on the hydrolysis of alpha-methyl-D-glucoside which was shown to be unaffected not only by amyloglucosidase of A. niger but also by that from a number of other organisms. The glucose released was measured by the glucose oxidase-peroxidase reagent, thus providing a rapid and reliable quantitative assay procedure for determining transglucosidase in the presence of amyloglucosidase. (Refs. 30).

  5. The Effectiveness of Antifungal Controlling Aspergillus Niger Growth on Plasterboard

    Directory of Open Access Journals (Sweden)

    Parjo Umi Kalthsom

    2017-01-01

    Full Text Available Good indoor environmental quality is desired for a healthy indoor environment. The microbial growth under indoor environments contribute to the poor indoor environmental quality that can cause various of health problems. In this study, the applications of three types of antifungals to prevent microbial migration, subsequent growth and bio-deterioration of the substrates. The aim of this research was to evaluate the coating-bio resistance in remediation of indoor fungal using three types of antifungals with different types of wall finishing materials. The treatment was exposed to optimum temperature and relative humidity at 30°C and 90% respectively. The potassium sorbate, zinc salicylate and calcium benzoate are tested against Aspergillus niger which is collected from indoor rooms. This study has revealed the growth of A. niger are more affected by the potassium sorbate on thick wallpaper, which is the percentage growth are 47%.

  6. Genetic studies with morphological mutants of Aspergillus niger

    International Nuclear Information System (INIS)

    Roy, Ponty; Das, Arati

    1979-01-01

    Three classes of coloured mutations, viz., fawn, yellow and green, occurred recurrently among the population following UV- and γ-radiation from Co 60 of a wild Aspergillus niger strain 350. Ten mutants were picked up and complementation tests were performed by growing them in pairwise combinations. In two cases, allelic mutants of the same colour were observed. All these mutants were again grown in pairwise crosses with a brown A. niger mutant of different lineage. A poor heterokaryotic growth was, however, observed in one combination which later produced a diploid heterozygous nucleus. It segregated spontaneously to develop a large variety of colonies ranging from haploidy to diploidy including aneuploids. These have been analysed genetically and the possible explanations have been given. (auth.)

  7. Novel pathway of NAD metabolism in Aspergillus niger

    International Nuclear Information System (INIS)

    Kuwahara, Masaaki

    1977-01-01

    New steps of NAD metabolism were shown in Aspergillus niger. Radioactive nicotinic acid and nicotinamide were incorporated into nicotinamide ribose diphosphate ribose (NAmRDPR), which had been isolated from the culture filtrate. The enzyme preparation of the mold degraded NAmRDPR to form nicotinamide mononucleotide and nicotinic acid under the neutral and alkaline conditions. In the acid extracts of the mycelia grown on the radioactive precursors, high level of radioactivity was detected on NAD. The experimental results showed that the Preiss-Handler pathway and the NAD cycling system function in the NAD biosynthesis in A. niger. A part of the radioactive precursors was also incorporated into nicotinic acid ribonucleoside, which was thought to be formed from nicotinic acid mononucleotide. (auth.)

  8. Uranium leaching using mixed organic acids produced by Aspergillus niger

    International Nuclear Information System (INIS)

    Yong-dong Wang; Guang-yue Li; De-xin Ding; Zhi-xiang Zhou; Qin-wen Deng; Nan Hu; Yan Tan

    2013-01-01

    Both of culture temperature and pH value had impacts on the degree of uranium extraction through changing types and concentrations of mixed organic acids produced by Aspergillus niger, and significant interactions existed between them though pH value played a leading role. And with the change of pH value of mixed organic acids, the types and contents of mixed organic acids changed and impacted on the degree of uranium extraction, especially oxalic acid, citric acid and malic acid. The mean degree of uranium extraction rose to peak when the culture temperature was 25 deg C (76.14 %) and pH value of mixed organic acids was 2.3 (82.40 %) respectively. And the highest one was 83.09 %. The optimal culture temperature (25 deg C) of A. niger for uranium leaching was different from the most appropriate growing temperature (37 deg C). (author)

  9. Effect of decoyinine on the regulation of alpha-amylase synthesis in Bacillus subtilis.

    OpenAIRE

    Nicholson, W L; Chambliss, G H

    1987-01-01

    Decoyinine, an inhibitor of GMP synthetase, allows sporulation in Bacillus subtilis to initiate and proceed under otherwise catabolite-repressing conditions. The effect of decoyinine on alpha-amylase synthesis in B. subtilis, an event which exhibits regulatory features resembling sporulation initiation, was examined. Decoyinine did not overcome catabolite repression of alpha-amylase synthesis in a wild-type strain of B. subtilis but did cause premature and enhanced synthesis in a mutant strai...

  10. Transcriptional regulation of the Bacillus subtilis menp1 promoter.

    OpenAIRE

    Qin, X; Taber, H W

    1996-01-01

    The Bacillus subtilis men genes encode biosynthetic enzymes for formation of the respiratory chain component menaquinone. The menp1 promoter previously was shown to be the primary cis element for menFD gene expression. In the present work, it was found that either supplementation with nonfermentable carbon sources or reutilization of glycolytic end products increased menp1 activity in the late postexponential phase. The effect on menp1 activity by a particular end product (such as acetoin or ...

  11. Screen for agents that induce autolysis in Bacillus subtilis.

    Science.gov (United States)

    Lacriola, Christopher J; Falk, Shaun P; Weisblum, Bernard

    2013-01-01

    The growing prevalence of antibiotic-resistant infections underscores the need to discover new antibiotics and to use them with maximum effectiveness. In response to these needs, we describe a screening protocol for the discovery of autolysis-inducing agents that uses two Bacillus subtilis reporter strains, SH-536 and BAU-102. To screen chemical libraries, autolysis-inducing agents were first identified with a BAU-102-based screen and then subdivided with SH-536 into two major groups: those that induce autolysis by their direct action on the cell membrane and those that induce autolysis secondary to inhibition of cell wall synthesis. SH-536 distinguishes between the two groups of autolysis-inducing agents by synthesizing and then releasing β-galactosidase (β-Gal) in late stationary phase at a time that cells have nearly stopped growing and are therefore tolerant of cell wall synthesis inhibitors. Four hits, named compound 2, compound 3, compound 5, and compound 24, obtained previously as inducers of autolysis by screening a 10,080-compound discovery library with BAU-102, were probed with SH-536 and found to release β-Gal, indicating that their mode of action was to permeabilize the B. subtilis cell membrane. The four primary hits inhibited growth in Staphylococcus aureus, Enterococcus faecium, Bacillus subtilis, and Bacillus anthracis, with MICs in the 12.5- to 25-μg/ml (20 to 60 μM) range. The four primary hits were further used to probe B. subtilis, and their action was partially characterized with respect to the dependence of induced autolysis on specific autolysins.

  12. Functional Diversity of AAA+ Protease Complexes in Bacillus subtilis

    OpenAIRE

    Elsholz, Alexander K. W.; Birk, Marlene S.; Charpentier, Emmanuelle; Turgay, K?r?ad

    2017-01-01

    Here, we review the diverse roles and functions of AAA+ protease complexes in protein homeostasis, control of stress response and cellular development pathways by regulatory and general proteolysis in the Gram-positive model organism Bacillus subtilis. We discuss in detail the intricate involvement of AAA+ protein complexes in controlling sporulation, the heat shock response and the role of adaptor proteins in these processes. The investigation of these protein complexes and their adaptor pro...

  13. Oscillating behavior of Clostridium difficile Min proteins in Bacillus subtilis.

    Science.gov (United States)

    Makroczyová, Jana; Jamroškovič, Ján; Krascsenitsová, Eva; Labajová, Nad'a; Barák, Imrich

    2016-06-01

    In rod-shaped bacteria, the proper placement of the division septum at the midcell relies, at least partially, on the proteins of the Min system as an inhibitor of cell division. The main principle of Min system function involves the formation of an inhibitor gradient along the cell axis; however, the establishment of this gradient differs between two well-studied gram-negative and gram-positive bacteria. While in gram-negative Escherichia coli, the Min system undergoes pole-to-pole oscillation, in gram-positive Bacillus subtilis, proper spatial inhibition is achieved by the preferential attraction of the Min proteins to the cell poles. Nevertheless, when E.coli Min proteins are inserted into B.subtilis cells, they still oscillate, which negatively affects asymmetric septation during sporulation in this organism. Interestingly, homologs of both Min systems were found to be present in various combinations in the genomes of anaerobic and endospore-forming Clostridia, including the pathogenic Clostridium difficile. Here, we have investigated the localization and behavior of C.difficile Min protein homologs and showed that MinDE proteins of C.difficile can oscillate when expressed together in B.subtilis cells. We have also investigated the effects of this oscillation on B.subtilis sporulation, and observed decreased sporulation efficiency in strains harboring the MinDE genes. Additionally, we have evaluated the effects of C.difficile Min protein expression on vegetative division in this heterologous host. © 2016 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  14. Use of bacillus subtilis strains to inhibit postharvest pathogenic fungi

    International Nuclear Information System (INIS)

    Arras, G.; Gambella, F.; Demontis, S.; Petretto, A.

    1995-01-01

    An isolate (87) of the bacillus subtilis strains isolated from cold stored citrus fruit 13 proved to inhibit the growth in vitro of the penicillium italicum used in the experiment (from 50.6% to 92.2%) and to inhibit botrytis cinerea (from 65.3% to 95.9%). A further test, superimposing on plates containing PDA strains Nos. 13, 173, and 160, totally inhibited the fungi. Tested in vivo on artificially bruised oranges, they significantly inhibited two fungi

  15. Biosynthesis of beta-glucosidase by Aspergillus niger a-5

    Energy Technology Data Exchange (ETDEWEB)

    Atev, A.; Panayotov, C.; Bubareva, L.; Benadova, R.; Kolev, E.

    1984-01-01

    Aspergillus niger A-5 produced beta-glucosidase, exocellobihydrolase (C1 enzyme) and endo-1, 4-beta-glucanase (Cx enzyme) in a culture medium containing farm residues of plant origin: wheat straw, ground maize stalks, wheat bran, and micricell as substrates. Maize stalk and wheat bran were the best inducers of the cellulase complex. Intensive aeration stimulated growth and enzyme synthesis. The highest beta-glucosidase activity (54 units/mL) was observed after 96 h of cultivation.

  16. New Pathway for Nonphosphorylated Degradation of Gluconate by Aspergillus niger

    Science.gov (United States)

    Elzainy, T. A.; Hassan, M. M.; Allam, A. M.

    1973-01-01

    A new nonphosphorylative pathway for gluconate degradation was found in extracts of a strain of Aspergillus niger. The findings indicate that gluconate is dehydrated into 2-keto-3-deoxy-gluconate (KDG), which then is cleaved into glyceraldehyde and pyruvate. 6-Phosphogluconate was not degraded under the same conditions. In addition, KDG was formed from glyceraldehyde and pyruvate. Very weak activity was obtained when glyceraldehyde 3-phosphate replaced glyceraldehyde in this reaction. PMID:4698214

  17. Mathematical model of gluconic acid fermentation by Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Takamatsu, T.; Shioya, S.; Furuya, T.

    1981-11-01

    A mathematical model for the study of gluconic acid fermentation by Aspergillus niger has been developed. The model has been deduced from the basic biological concept of multicellular filamentous microorganisms, i.e. cell population balance. It can be used to explain the behaviour of both batch and continuous cultures, even when in a lag phase. A new characteristic, involving the existence of dual equilibrium stages during fermentation, has been predicted using this mathematical model. (Refs. 6).

  18. The effect of Aspergillus niger mutagenization on citric acid biosynthesis

    Directory of Open Access Journals (Sweden)

    Stanisław Walisch

    2014-08-01

    Full Text Available The industrial A. niger strain producing citric acid was mutagenized with the use of new chemical mutagens: free nitroxyl radicals. Strains of higher citric acid production yield were obtained. Citric acid was produced in a shorter time compared to the initial strain. During 6-12 months of storage most of the strains preserved their positive features which proves that mutants with profitable biotechnological properties were obtained. These mutants are used in industrial process.

  19. FluG affects secretion in colonies of Aspergillus niger.

    Science.gov (United States)

    Wang, Fengfeng; Krijgsheld, Pauline; Hulsman, Marc; de Bekker, Charissa; Müller, Wally H; Reinders, Marcel; de Vries, Ronald P; Wösten, Han A B

    2015-01-01

    Colonies of Aspergillus niger are characterized by zonal heterogeneity in growth, sporulation, gene expression and secretion. For instance, the glucoamylase gene glaA is more highly expressed at the periphery of colonies when compared to the center. As a consequence, its encoded protein GlaA is mainly secreted at the outer part of the colony. Here, multiple copies of amyR were introduced in A. niger. Most transformants over-expressing this regulatory gene of amylolytic genes still displayed heterogeneous glaA expression and GlaA secretion. However, heterogeneity was abolished in transformant UU-A001.13 by expressing glaA and secreting GlaA throughout the mycelium. Sequencing the genome of UU-A001.13 revealed that transformation had been accompanied by deletion of part of the fluG gene and disrupting its 3' end by integration of a transformation vector. Inactivation of fluG in the wild-type background of A. niger also resulted in breakdown of starch under the whole colony. Asexual development of the ∆fluG strain was not affected, unlike what was previously shown in Aspergillus nidulans. Genes encoding proteins with a signal sequence for secretion, including part of the amylolytic genes, were more often downregulated in the central zone of maltose-grown ∆fluG colonies and upregulated in the intermediate part and periphery when compared to the wild-type. Together, these data indicate that FluG of A. niger is a repressor of secretion.

  20. Biotransformation of steviol derivatives by Aspergillus niger and Fusarium moniliforme

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Bras H. de; Leal, Paulo C. [Parana Univ., Curitiba, PR (Brazil). Dept. de Quimica]. E-mail: bho@ufpr.br; Souza Filho, Jose Dias [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Quimica

    2005-04-01

    Steviol derivatives have been submitted to biotransformations by fungi. Methyl ent-11{beta},13-dihydroxy-15,16-epoxikauran-19-oate was hydroxylated at C-11 by Aspergillus niger, whereas ent-16{beta}-hydroxybeyeran-19-oic acid was hydroxylated at C-6 and C-7 by Fusarium moniliforme. The hydroxylation at non-activated positions at the carbon skeleton is discussed in connection with the properties of important polyhydroxylated diterpenoids described in the literature. (author)

  1. Biotransformation of steviol derivatives by Aspergillus niger and Fusarium moniliforme

    International Nuclear Information System (INIS)

    Oliveira, Bras H. de; Leal, Paulo C.; Souza Filho, Jose Dias

    2005-01-01

    Steviol derivatives have been submitted to biotransformations by fungi. Methyl ent-11β,13-dihydroxy-15,16-epoxikauran-19-oate was hydroxylated at C-11 by Aspergillus niger, whereas ent-16β-hydroxybeyeran-19-oic acid was hydroxylated at C-6 and C-7 by Fusarium moniliforme. The hydroxylation at non-activated positions at the carbon skeleton is discussed in connection with the properties of important polyhydroxylated diterpenoids described in the literature. (author)

  2. Waste management in the uranium companies of Niger

    International Nuclear Information System (INIS)

    Hama, A.

    2002-01-01

    Two companies produce uranium (yellowcake) in Niger: the 'Societe des Mines de l'Air (SOMAIR)' and the 'Compagnie Miniere d'Akouta (COMINAK)'. The SOMAIR operation uses open pit mining whereas COMINAK employs underground mining. Uranium ores have been treated by SOMAIR and COMINAK since 1971 and 1978 respectively. The wastes produced by the two companies will be managed to reduce health and environment impacts. (author)

  3. Prévention et gestion des conflits au Niger

    OpenAIRE

    Souley, A.

    1996-01-01

    Metadata only record A general description of conflict causes and management in Niger. The author identifies five different types of causes according to their nature: political, socio-economic, management of natural resources, frontier, and ethnic/religious. Natural resource management conflicts stem from demographic pressure, urbanization, drought, and a deteriorating resource base. The current conflict between herders and farmers is characterized as occurring during a transitional phase ...

  4. Some factors affecting tannase production by Aspergillus niger Van Tieghem

    OpenAIRE

    Aboubakr, Hamada A.; El-Sahn, Malak A.; El-Banna, Amr A.

    2013-01-01

    One variable at a time procedure was used to evaluate the effect of qualitative variables on the production of tannase from Aspergillus niger Van Tieghem. These variables including: fermentation technique, agitation condition, tannins source, adding carbohydrates incorporation with tannic acid, nitrogen source type and divalent cations. Submerged fermentation under intermittent shaking gave the highest total tannase activity. Maximum extracellular tannase activity (305 units/ 50 mL) was attai...

  5. IMMOBILIZATION OF TANNIN ACYL HYDROLASE FROM ASPERGILLUS NIGER

    OpenAIRE

    B. Lenin Kumar*, N. Lokeswari and D. Sriramireddy

    2013-01-01

    ABSTRACT: Tannin acyl hydrolase, commonly referred to as tannase (E.C. 3.1.1.20), an inducible extra-cellular enzyme produced by a number of animals, plants and microbes. In this investigation, tannase production under solid-state fermentation by using Aspergillus niger and the waste residue of cashew husk was used as substrate for obtaining the desired fermented product. Microbial tannase is more stable than tannase from other sources like plants or animals. Tannase from fungal sources are r...

  6. Catalytical Properties of Free and Immobilized Aspergillus niger Tannase

    OpenAIRE

    Abril Flores-Maltos; Luis V. Rodríguez-Durán; Jacqueline Renovato; Juan C. Contreras; Raúl Rodríguez; Cristóbal N. Aguilar

    2011-01-01

    A fungal tannase was produced, recovered, and immobilized by entrapment in calcium alginate beads. Catalytical properties of the immobilized enzyme were compared with those of the free one. Tannase was produced intracellularly by the xerophilic fungus Aspergillus niger GH1 in a submerged fermentation system. Enzyme was recovered by cell disruption and the crude extract was partially purified. The catalytical properties of free and immobilized tannase were evaluated using tannic acid and methy...

  7. Effect of nutrient components for phytase production by Aspergillus niger

    OpenAIRE

    KALIYEVA AIGUL; SULEIMENOVA ZHANARA; AKHMETSADYKOV NURLAN; SADUYEVA ZHAZIRA

    2015-01-01

    In present study the effect of carbon sources, glucose, sucrose, lactose, maltose, fructose, xylose and nitrogen sources such as ammonium sulfate, ammonium phosphate, ammonium nitrate, potassium nitrate, yeast extract, peptone on the phytase production has been studied. Maximal phytase activity of Aspergillus niger was detected in media with 1.0% sucrose as a carbon source. All other monosaccharides and disaccharides used had less effect on phytase production. Among the inorganic and organic ...

  8. Identification of thermostable β-xylosidase activities produced by Aspergillus brasiliensis and Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Mads; Lauritzen, Henrik Klitgaard; Frisvad, Jens Christian

    2007-01-01

    Twenty Aspergillus strains were evaluated for production of extracellular cellulolytic and xylanolytic activities. Aspergillus brasiliensis, A. niger and A. japonicus produced the highest xylanase activities with the A. brasiliensis and A. niger strains producing thermostable beta......-xylosidases. The beta-xylosidase activities of the A. brasiliensis and A. niger strains had similar temperature and pH optima at 75 degrees C and pH 5 and retained 62% and 99%, respectively, of these activities over 1 h at 60 degrees C. At 75 degrees C, these values were 38 and 44%, respectively. Whereas A. niger...

  9. How can the origin of the decay var-phi →3π be determined?

    International Nuclear Information System (INIS)

    Achasov, N.N.; Kozhevnikov, A.A.

    1992-01-01

    It is shown that the interference pattern in the region √s = 1.05 GeV in the reaction e + e - →ω, var-phi →3π can be used to determine unambiguously whether the decay var-phi →3π occurs because of var-phi ω mixing, var-phi →ω→3π, or because of the direct transition var-phi →3π. 8 refs., 3 figs., 1 tab

  10. Sporulation during growth in a gut isolate of Bacillus subtilis.

    Science.gov (United States)

    Serra, Cláudia R; Earl, Ashlee M; Barbosa, Teresa M; Kolter, Roberto; Henriques, Adriano O

    2014-12-01

    Sporulation by Bacillus subtilis is a cell density-dependent response to nutrient deprivation. Central to the decision of entering sporulation is a phosphorelay, through which sensor kinases promote phosphorylation of Spo0A. The phosphorelay integrates both positive and negative signals, ensuring that sporulation, a time- and energy-consuming process that may bring an ecological cost, is only triggered should other adaptations fail. Here we report that a gastrointestinal isolate of B. subtilis sporulates with high efficiency during growth, bypassing the cell density, nutritional, and other signals that normally make sporulation a post-exponential-phase response. Sporulation during growth occurs because Spo0A is more active per cell and in a higher fraction of the population than in a laboratory strain. This in turn, is primarily caused by the absence from the gut strain of the genes rapE and rapK, coding for two aspartyl phosphatases that negatively modulate the flow of phosphoryl groups to Spo0A. We show, in line with recent results, that activation of Spo0A through the phosphorelay is the limiting step for sporulation initiation in the gut strain. Our results further suggest that the phosphorelay is tuned to favor sporulation during growth in gastrointestinal B. subtilis isolates, presumably as a form of survival and/or propagation in the gut environment. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  11. Isolation and characterization of lipopeptide antibiotics produced by Bacillus subtilis.

    Science.gov (United States)

    Chen, H; Wang, L; Su, C X; Gong, G H; Wang, P; Yu, Z L

    2008-09-01

    Antibiotics from Bacillus subtilis JA show strong pathogen inhibition ability, which has potential market application; yet, the composition of these antibiotics has not been elucidated. The aim of this paper is to isolate and identify these antibiotics. The antagonistic activity of JA was tested in vitro; it exhibited strong inhibition against some important phytopathogens and postharvest pathogens. Crude antibiotic production was extracted with methanol from the precipitate by adding 6 mol l(-1) HCl to the bacillus-free culture broth. The crude extract was run on Diamonsil C18 column (5 microm, 250 x 4.6 mm) in HPLC system to separate the antibiotics. Major antibiotics were classified into three lipopeptide families according to electrospray ionization-mass spectrometry analysis. Subsequently, the classification of antibiotics was confirmed with typical collision-induced dissociation fragments. Three kinds of antibiotics were isolated from B. subtilis JA and were identified to the lipopeptide families, surfactin, iturin and fengycin. These compounds could function as biocontrol agents against a large spectrum of pathogens. This study provided a reliable and rapid method for isolation and structural characterization of lipopeptide antibiotics from B. subtilis.

  12. Bottleneck in secretion of α-amylase in Bacillus subtilis.

    Science.gov (United States)

    Yan, Shaomin; Wu, Guang

    2017-07-19

    Amylase plays an important role in biotechnology industries, and Gram-positive bacterium Bacillus subtilis is a major host to produce heterogeneous α-amylases. However, the secretion stress limits the high yield of α-amylase in B. subtilis although huge efforts have been made to address this secretion bottleneck. In this question-oriented review, every effort is made to answer the following questions, which look simple but are long-standing, through reviewing of literature: (1) Does α-amylase need a specific and dedicated chaperone? (2) What signal sequence does CsaA recognize? (3) Does CsaA require ATP for its operation? (4) Does an unfolded α-amylase is less soluble than a folded one? (5) Does α-amylase aggregate before transporting through Sec secretion system? (6) Is α-amylase sufficient stable to prevent itself from misfolding? (7) Does α-amylase need more disulfide bonds to be stabilized? (8) Which secretion system does PrsA pass through? (9) Is PrsA ATP-dependent? (10) Is PrsA reused after folding of α-amylase? (11) What is the fate of PrsA? (12) Is trigger factor (TF) ATP-dependent? The literature review suggests that not only the most of those questions are still open to answers but also it is necessary to calculate ATP budget in order to better understand how B. subtilis uses its energy for production and secretion.

  13. Molecular mechanisms involved in Bacillus subtilis biofilm formation

    Science.gov (United States)

    Mielich-Süss, Benjamin; Lopez, Daniel

    2014-01-01

    Summary Biofilms are the predominant lifestyle of bacteria in natural environments, and they severely impact our societies in many different fashions. Therefore, biofilm formation is a topic of growing interest in microbiology, and different bacterial models are currently studied to better understand the molecular strategies that bacteria undergo to build biofilms. Among those, biofilms of the soil-dwelling bacterium Bacillus subtilis are commonly used for this purpose. Bacillus subtilis biofilms show remarkable architectural features that are a consequence of sophisticated programs of cellular specialization and cell-cell communication within the community. Many laboratories are trying to unravel the biological role of the morphological features of biofilms, as well as exploring the molecular basis underlying cellular differentiation. In this review, we present a general perspective of the current state of knowledge of biofilm formation in B. subtilis. In particular, a special emphasis is placed on summarizing the most recent discoveries in the field and integrating them into the general view of these truly sophisticated microbial communities. PMID:24909922

  14. Thiopeptide antibiotics stimulate biofilm formation in Bacillus subtilis.

    Science.gov (United States)

    Bleich, Rachel; Watrous, Jeramie D; Dorrestein, Pieter C; Bowers, Albert A; Shank, Elizabeth A

    2015-03-10

    Bacteria have evolved the ability to produce a wide range of structurally complex natural products historically called "secondary" metabolites. Although some of these compounds have been identified as bacterial communication cues, more frequently natural products are scrutinized for antibiotic activities that are relevant to human health. However, there has been little regard for how these compounds might otherwise impact the physiology of neighboring microbes present in complex communities. Bacillus cereus secretes molecules that activate expression of biofilm genes in Bacillus subtilis. Here, we use imaging mass spectrometry to identify the thiocillins, a group of thiazolyl peptide antibiotics, as biofilm matrix-inducing compounds produced by B. cereus. We found that thiocillin increased the population of matrix-producing B. subtilis cells and that this activity could be abolished by multiple structural alterations. Importantly, a mutation that eliminated thiocillin's antibiotic activity did not affect its ability to induce biofilm gene expression in B. subtilis. We go on to show that biofilm induction appears to be a general phenomenon of multiple structurally diverse thiazolyl peptides and use this activity to confirm the presence of thiazolyl peptide gene clusters in other bacterial species. Our results indicate that the roles of secondary metabolites initially identified as antibiotics may have more complex effects--acting not only as killing agents, but also as specific modulators of microbial cellular phenotypes.

  15. Production and Purification of Peroxidase from Aspergillus niger.

    Directory of Open Access Journals (Sweden)

    Mohammed A. Jebor

    2017-02-01

    Full Text Available This study was conducted in the laboratories of Biology Department, College of Science, which deals with isolation and purification of peroxidase and optimization of process parameters to achieve maximum yield of peroxidase by Aspergillus niger. Solid-state fermentation of Aspergillus niger was carried out for enhanced production of peroxidase using hydrogen peroxide as the substrate of enzyme maximum activity of the enzyme was achieved under optimum growth conditions. The optimum conditions were the isolated of Aspergillus niger from soil and growth in synthetic medium, it gave high titer of peroxidase activity, the fructose as carbon source, peptone as nitrogen source, after 12 days of incubation, incubation temperature 25 °C and pH = 6.5. Peroxidase purified in four purification steps; precipitation with 70% saturation of ammonium sulfate, step of dialysis, the third by ion exchange chromatography using DEAE-Cellulose and fourth by gel filtration throughout Sephadex G-100. The specific activity of the purified enzyme was 150U/mg with 7.75 folds. The peroxidase was shown to have molecular weight of 40kDa in SDS-PAGA and about 40kDa in gel filtration.The optimum pH and temperature for peroxidase activity 7 and 35 C0 respectively.

  16. Sorption of 241Am by Aspergillus niger spore and hyphae

    International Nuclear Information System (INIS)

    Yuanyou Yang; Ning Liu; Jiali Liao; Jiannan Jin; Shunzhong Luo; Taiming Zhang; Pengji Zhao

    2004-01-01

    Biosorption of 241 Am by a fungus A. niger, including the spore and hyphae, was investigated. The preliminary results showed that the adsorption of 241 Am by the microorganism was efficient. More than 96% of the total 241 Am could be removed from 241 Am solutions of 5.6-111 MBq/l (C 0 ) by spore and hyphae of A. niger, with adsorbed 241 Am metal (Q) of 7.2-142.4 MBq/g biomass, and 5.2-106.5 MBq/g, respectively. The biosorption equilibrium was achieved within 1 hour and the optimum pH range was pH 1-3. No obvious effects on 241 Am adsorption by the fungus were observed at 10-45 deg C, or in solutions containing Au 3+ or Ag + , even 2000 times above the 241 Am concentration. The 241 Am biosorption by the fungus obeys the Freundlich adsorption equation. There was no significant difference between the adsorption behavior of A. niger spore and hyphae. (author)

  17. Examining Nutritional Adequacy and Dietary Diversity Among Women in Niger.

    Science.gov (United States)

    Cisse-Egbuonye, Nafissatou; Ishdorj, Ariun; McKyer, E L J; Mkuu, Rahma

    2017-06-01

    Objective The purpose of this study was to examine the nutritional adequacy and dietary composition among women residing in Zinder and Maradi of Niger, and the factors that affect the variety of their dietary intake. Methods Data from 3360 women of ages 15-49 were used in the analysis. The variable of interest was the Women Dietary Diversity Score (WDDS), which is the simple sum of scores of the 9 categorized food groups, ranging from 0 to 9. Lower values for WDDS indicate nutritionally inadequate dietary diversity. Analysis included descriptive, Mann-Whitney U test and linear regression. Results The majority of the participants were residing in the Maradi Region (56.7%) and were living in households with both male and female adults (94.9%). The mean WDDS was 3.5 in Zinder compared to 2.5 in Maradi (p Hunger Scale (HHS) had a negative and significant effect on WDDS. Conclusion Niger has one of the highest concentrations of malnutrition in the world. In 2012, approximately 2.5 million Nigeriens were affected by malnutrition. Our study results reinforce the importance to conduct more studies that examine the nutritional intake of women in Niger.

  18. Substrate water availability and seed water content on niger germination

    Directory of Open Access Journals (Sweden)

    Carla Regina Baptista Gordin

    2015-09-01

    Full Text Available Niger is an oleaginous species whose cultivation has been spreading, but there is not much information on the adverse conditions during its seedling establishment. This study aimed at evaluating the effects of substrate water availability and seed water content on niger germination. Seeds were moistened using the humid atmosphere method for 0; 24; 48; and 72 hours, obtaining the water contents of 7.0 %, 12.8 %, 16.8 % and 32.2 %. Then, they were sown in substrate moistened with PEG 6000 solutions with different osmotic potentials: 0.0 MPa (control, -0.1 MPa, -0.2 MPa, -0.3 MPa and -0.4 MPa. A completely randomized design, in a 4 x 5 factorial scheme (water content x osmotic potential, with four replications of 50 seeds, was used. First count and germination percentage, germination speed index and mean time, shoot and root length and seedlings dry weight were evaluated. The reduction in the substrate osmotic potential decreases the niger seed germination and seedling growth, regardless of water content, but with a higher evidence in seed water contents below 32.2 % and 12.8 %, respectively.

  19. [You will become a saleswoman, my girl. Press review: Niger].

    Science.gov (United States)

    1999-12-01

    In the Maradi district of southwestern Niger, the country¿s commercial hub, children are born with business sense. Parents in the district expect their young daughters to take part in the region¿s business activities by selling products at village markets. Therefore, only 13% of girls in the district attend school and during market days, classrooms are almost empty, but particularly devoid of female students. Students in Sabon Machi village have school vacation every Tuesday in order to attend the weekly market, then catch up on coursework on Wednesdays. Parents approve of such district norms because they prefer to keep their girls at home to help with household chores. Otherwise, they enroll their daughters in a Koranic school, where they can learn the basics of becoming a wife. Girls in this part of Niger are either promised to someone else in the future or they are under the control of their mothers, who are charged with teaching daughters what they need to know to be proper wives. Girls sell market products to slowly accumulate funds for their dowries. Also with regard to daughters, many parents believe that school attendance is synonymous with unwanted pregnancies, abortions, and other sorts of aberrations. Niger¿s government and nongovernmental organizations (NGOs) are wondering how to convince parents in this region to send their daughters to school. Some approaches employed to reassure and convince parents to that end are described.

  20. Floods in the Niger basin - analysis and attribution

    Science.gov (United States)

    Aich, V.; Koné, B.; Hattermann, F. F.; Müller, E. N.

    2014-08-01

    This study addresses the increasing flood risk in the Niger basin and assesses the damages that arise from flooding. Statistics from three different sources (EM-DAT, Darthmouth Flood Observatory, NatCat Munich RE) on people affected by floods show positive trends for the entire basin beginning in the 1980s. An assessment of four subregions across the Niger basin indicates even exponential trends for the Sahelian and Sudanian regions. These positive trends for flooding damage match up to a time series of annual maximum discharge (AMAX): the strongest trends in AMAX are detected in the Sahelian and Sudanian regions, where the population is also increasing the fastest and vulnerability generally appears to be very high. The joint effect of these three factors can possibly explain the exponential increase in people affected by floods in these subregions. In a second step, the changes in AMAX are attributed to changes in precipitation and land use via a data-based approach within a hypothesis-testing framework. Analysis of rainfall, heavy precipitation and the runoff coefficient shows a coherent picture of a return to wet conditions in the basin, which we identify as the main driver of the increase in AMAX in the Niger basin. The analysis of flashiness (using the Richards-Baker Index) and the focus on the "Sahel Paradox" of the Sahelian region reveal an additional influence of land-use change, but it seems minor compared to the increase in precipitation.

  1. Gurya cutting and female genital fistulas in Niger: ten cases.

    Science.gov (United States)

    Ouedraogo, Itengre; McConley, Regina; Payne, Christopher; Heller, Alison; Wall, L Lewis

    2018-03-01

    The objective was to determine the contribution of female genital cutting to genital fistula formation in Niger from the case records of a specialist fistula hospital. A retrospective review was undertaken of the records of 360 patients seen at the Danja Fistula Center, Danja, Niger, between March 2014 and September 2016. Pertinent clinical and socio-demographic data were abstracted from the cases identified. A total of 10 fistulas resulting from gurya cutting was obtained: 9 cases of urethral loss and 1 rectovaginal fistula. In none of the cases was genital cutting performed for obstructed labor or as part of ritual coming-of-age ceremonies, but all cutting procedures were considered "therapeutic" within the local cultural context as treatment for dyspareunia, lack of interest in or unwillingness to engage in sexual intercourse, or female behavior that was deemed to be culturally inappropriate by the male spouse, parents, or in-laws. Clinical cure (fistula closed and the patient continent) was obtained in all 10 cases, although 3 women required more than one operation. Gurya cutting is an uncommon, but preventable, cause of genital fistulas in Niger. The socio-cultural context which gives rise to gurya cutting is explored in some detail.

  2. Inducible error-prone repair in B. subtilis. Progress report, September 1, 1979-February 28, 1981

    International Nuclear Information System (INIS)

    Yasbin, R.E.

    1980-10-01

    The mechanism of activation and the mode of action of the SOS system in Bacillus subtilis are being investigated. Interesting aspects of the SOS system in B. subtilis include: (1) the differences between the SOS functions in this bacterium and in the enteric bacteria; (2) the spontaneous activation of SOS functions in competent cells; and (3) the difficulty in establishing the presence of error-prone repair in this bacterium. In order to characterize the SOS system of B. subtilis, attempts will be made to: (1) isolate bacteria mutated in genes controlling various repair functions; (2) investigate inducible repair; (3) determine the role of endogenous prophages in DNA repair phenomena; and (4) utilize competent B. subtilis as a tester system for the detection of potential carcinogens. Data obtained during the past 18 months demonstrate: (1) the ability of the B. subtilis Comptest to detect potential environmental carcinogens; (2) the importance of DNA polymerase III in W-reactivation in B. subtilis; and (3) the control the bacteriophage SPβ has over the inducible DNA modification system in B. subtilis. Furthermore, the data also suggests the lack of error-prone repair in B. subtilis, and the differences which exist between the Bacilli and the enteric bacteria with regards to SOS phenomena. In order to further characterize inducible repair functions in B. subtilis, results will also be presented on attempts to mobilize error-prone repair systems of other bacterial species

  3. Genetic transformation of Bacillus strains close to bacillus subtilis and isolated from the soil

    International Nuclear Information System (INIS)

    Van, C.K.; Kuzin, Yu.Yu.; Kozlovskii, Yu.E.; Prozorov, A.A.

    1986-01-01

    Chromosomal and plasmid transformation was found in five out of 118 Bacillus strains, close or identical to Bacillus subtilis, and isolated from soil in Moscow or in the Moscow district. The efficiency of transformation in these strains was lower than that in derivatives of Bac. subtilis strain 168. In these strains the ability to undergo transformation was dependent on the rate of sporulation and the presence of restrictases. As in the case of Bac. subtilis 168 the strains isolated may be used as models in genetic transformation studies on Bac. subtilis

  4. Inducible error-prone repair in B. subtilis. Progress report, September 1, 1978-August 31, 1979

    International Nuclear Information System (INIS)

    Yasbin, R.E.

    1979-01-01

    The mechanism of activation and the mode of action of the SOS system in the bacterium Bacillus subtilis is under study. Interesting aspects of the SOS system in B. subtilis are: (1) the differences between SOS functions in this bacterium and in the enteric bacteria; (2) the spontaneous activation of SOS functions in component cells; and (3) the difficulty in obtaining consistent results for mutation studies in this bacterium. In order to characterize the SOS system of B. subtilis, it was proposed to: (1) isolate bacteria mutated in genes controlling various repair function; (2) investigate inducible repair; (3) determine the role of endogeneous Bacillus prophages in SOS functions; and (4) develop a tester system for potential carcinogens from competent Bacillus subtilis cells. Research has been able to: (1) isolate strains of B. subtilis in which the endogeneous prophages have been removed or neutralized; (2) demonstrate the association of one SOS function with prophage SPB; (3) demonstrate that the survival of uv-irradiated B. subtilis is not significantly altered by the removal and neutralization of the endogeneous prophages; (4) develop competant B. subtilis into a tester system; and (5) show that DNA polymerase III is absolutely necessary for W reactivation. In addition, uv and mitomycin C resistant mutants have been isolated and inducible postreplication repair in excision-repair deficient mutants of B. subtilis has been studied. The last two results are somewaht confusing but highly exciting in regards to DNA repair mechanisms in B. subtilis

  5. Inducible error-prone repair in B. subtilis. Progress report, May 1, 1983-April 30, 1984

    International Nuclear Information System (INIS)

    Yasbin, R.E.

    1983-12-01

    DNA repair mechanisms in Bacillus subtilis were investigated following mutagenesis via ultraviolet radiation or by chemical mutagens. A bioassay is described whereby the efficiency of repair mechanisms can be measured. DNA cloning studies to transfer the photoreactivation gene from E. coli to B. subtilis are reported. The mutation, which induces the SOS-like system in B. subtilis when grown at 45 0 C, was characterized in order to begin delineation of the genes controlling this system, efforts directed at isolation and cloning of a DNA Polymerase III gene of B. subtilis are related. (DT)

  6. Activation and clustering of a Plasmodium falciparum var gene are affected by subtelomeric sequences.

    Science.gov (United States)

    Duffy, Michael F; Tang, Jingyi; Sumardy, Fransisca; Nguyen, Hanh H T; Selvarajah, Shamista A; Josling, Gabrielle A; Day, Karen P; Petter, Michaela; Brown, Graham V

    2017-01-01

    The Plasmodium falciparum var multigene family encodes the cytoadhesive, variant antigen PfEMP1. P. falciparum antigenic variation and cytoadhesion specificity are controlled by epigenetic switching between the single, or few, simultaneously expressed var genes. Most var genes are maintained in perinuclear clusters of heterochromatic telomeres. The active var gene(s) occupy a single, perinuclear var expression site. It is unresolved whether the var expression site forms in situ at a telomeric cluster or whether it is an extant compartment to which single chromosomes travel, thus controlling var switching. Here we show that transcription of a var gene did not require decreased colocalisation with clusters of telomeres, supporting var expression site formation in situ. However following recombination within adjacent subtelomeric sequences, the same var gene was persistently activated and did colocalise less with telomeric clusters. Thus, participation in stable, heterochromatic, telomere clusters and var switching are independent but are both affected by subtelomeric sequences. The var expression site colocalised with the euchromatic mark H3K27ac to a greater extent than it did with heterochromatic H3K9me3. H3K27ac was enriched within the active var gene promoter even when the var gene was transiently repressed in mature parasites and thus H3K27ac may contribute to var gene epigenetic memory. © 2016 Federation of European Biochemical Societies.

  7. VAr reserve concept applied to a wind power plant

    DEFF Research Database (Denmark)

    Martinez, Jorge; Kjær, Philip C.; Rodriguez, Pedro

    2011-01-01

    to wind power plants. This paper proposes two different VAr reserve control strategies for a wind power plant. The amount of dynamic VAr available most of the operation time, makes the wind power plant (WPP) a good candidate to include a VAr reserve management system. Two different ways of implementing...... a VAr management system are proposed and analyzed. Such a reactive power reserve may be provided by the wind power plant since the amount of reactive power installed for most active power working points exceeds the demand required by the grid operator. Basically, this overrated reactive power capacity...... is a consequence of sizing wind turbine facilities for maximum active power level. The reactive power losses, due to active power transportation inside the plant (normally two transformers), and P-Q wind turbine characteristics define the P-Q reserve chart. By utilizing the intrinsic overrated reactive power...

  8. Molt disruption and mortality of Locusta migratoria var. manilensis ...

    African Journals Online (AJOL)

    IGRs) on the oriental migratory locust Locusta migratoria var. manilensis were assessed. Under laboratory conditions, at the highest tested dose rate of 300 ppm, the percent mortality and molt inhibition after two weeks for the five tested ...

  9. ClinVar data parsing [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Xiaolei Zhang

    2017-05-01

    Full Text Available This software repository provides a pipeline for converting raw ClinVar data files into analysis-friendly tab-delimited tables, and also provides these tables for the most recent ClinVar release. Separate tables are generated for genome builds GRCh37 and GRCh38 as well as for mono-allelic variants and complex multi-allelic variants. Additionally, the tables are augmented with allele frequencies from the ExAC and gnomAD datasets as these are often consulted when analyzing ClinVar variants. Overall, this work provides ClinVar data in a format that is easier to work with and can be directly loaded into a variety of popular analysis tools such as R, python pandas, and SQL databases.

  10. Immunogenic Properties of Ricinus Communis Var Minor Seed on ...

    African Journals Online (AJOL)

    Prof. Ogunji

    1College of Health Technology, Zawan, Plateau State.2Department of ... Ricinus communis var minor seed included in their feed (5g/100g body weight). ... White Blood cell Count (WBC) count and lymphocytosis in the differential count.

  11. Analcite formation in the Agades Region (Niger); Les formations a analcime de la Region d'Agades (Republique du Niger)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1966-06-01

    A study based mainly upon field mapping and drill cores examination, followed by a laboratory survey allows us to support a genetic hypothesis upon the formation of analcime in the 'Continental intercalaire' of Agades (Niger). Analcime could be generated from an early diagenesis of argillaceous sediments influenced by high soda content fossil waters inside confined continental sedimentary basins. (authors) [French] Une etude axee essentiellement sur des leves de terrain et des carottes de sondages, suivie d'une etude en laboratoire, permet d'avancer une hypothese genetique sur les formations a analcime du Continental Intercalaire d'AGADES (Niger). L'analcime resulterait d'une diagenese precoce de sediments argileux, sous l'influence d'eaux connees riches en soude, dans des bassins sedimentaires continentaux confines.

  12. Cloning of the Bacillus subtilis recE+ gene and functional expression of recE+ in B. subtilis

    International Nuclear Information System (INIS)

    Marrero, R.; Yasbin, R.E.

    1988-01-01

    By use of the Bacillus subtilis bacteriophage cloning vehicle Phi 105J23, B. subtilis chromosomal MboI fragments have been cloned that alleviate the pleiotropic effects of the recE4 mutation. The recombinant bacteriophages Phi 105Rec Phi1 (3.85-kilobase insert) and Phi 105Rec Phi4 (3.3-kilobase insert) both conferred on the recE4 strain YB1015 resistance to ethylmethane sulfonate, methylmethane sulfonate, mitomycin C, and UV irradiation comparable with the resistance observed in recE + strains. While strain YB1015 (recE4) and its derivatives lysogenized with bacteriophage Phi105J23 were not transformed to prototrophy by B. subtilis chromosomal DNA, strain YB1015 lysogenized with either Phi 105Rec Phi 1 or Phi 105RecPhi 4 was susceptible to transformation with homologous B. subtilis chromosomal DNA. The heteroimmune prophages Phi 105 and SPO2 were essentially uninducible in strain YB1015. Significantly, both recombinant prophages Phi 105RecPhi 1 and Phi 105Rec Phi 4 were fully inducible and allowed the spontaneous and mitomycin C-dependent induction of a coresident SPO2 prophage in a recE4 host. The presence of the recombinant prophages also restored the ability of din genes to be induced in strains carrying the recE4 mutation. Finally, both recombinant bacteriophages elaborated a mitomycin C-inducible, 45-kilodalton protein that was immunoreactive with Escherichia coli recA + gene product antibodies. Collectively, these data demonstrate that the recE + gene has been cloned and that this gene elaborates the 45-kilodalton protein that is involved in SOB induction and homologous recombination

  13. Orientation of the Fiscal Policy in Tunisia: Structural VAR Analysis

    Directory of Open Access Journals (Sweden)

    Wissem Khanfir

    2017-06-01

    Full Text Available The objective of this paper is to indicate the orientation of fiscal policy in Tunisia, using the structural budget balance, during the period 1972-2014. For this purpose, we estimate a structural VAR model consisting of the fiscal deficit to current GDP ratio and the volume of economic activity represented by the real GDP. We estimate bivariate structural VAR in order to decompose fiscal deficit fluctuations into different disturbances.

  14. An orientin derivative isolated from Passiflora tripartita var. mollissima

    OpenAIRE

    Ramos, Freddy A.; Castellanos, Leonardo; López, César; Palacios, Lizeth; Duque, Carmenza; Pacheco, Ricardo; Guzmán, Antonio

    2010-01-01

    Passiflora tripartita var. mollisima (banana passion fruit) is an edible fruit widespread in the Andean highlands of Colombia and Ecuador. The fruit is used for juices as well as for the sedative properties of the leaves. As a contribution to the chemical characterization of this species, a new compound, 4'- methoxyluteolin-8-C-6”acetylglucopyranoside, was isolated from the ethanolic extract of Passiflora tripartita var. mollisima leaves and identified by spectroscopical data (NMR, MS, UV).

  15. Da abort ikke var en sag for kvinden

    DEFF Research Database (Denmark)

    Schultz, Annette Østergaard

    2013-01-01

    Case fra tiden før 1973, hvor der ikke var fri abort i Danmark. Sagen er fundet i Mødrehjælpens arkiv og giver som andre sager indblik i kvindens situation. Led i serien: Nyt i arkivet.......Case fra tiden før 1973, hvor der ikke var fri abort i Danmark. Sagen er fundet i Mødrehjælpens arkiv og giver som andre sager indblik i kvindens situation. Led i serien: Nyt i arkivet....

  16. Saccharomyces cerevisiae var. boulardii fungemia following probiotic treatment

    OpenAIRE

    Appel-da-Silva, Marcelo C.; Narvaez, Gabriel A.; Perez, Leandro R.R.; Drehmer, Laura; Lewgoy, Jairo

    2017-01-01

    Probiotics are commonly prescribed as an adjuvant in the treatment of antibiotic-associated diarrhea caused by Clostridium difficile. We report the case of an immunocompromised 73-year-old patient on chemotherapy who developed Saccharomyces cerevisiae var. boulardii fungemia in a central venous catheter during treatment of antibiotic-associated pseudomembranous colitis with the probiotic Saccharomyces cerevisiae var. boulardii. Fungemia was resolved after interruption of probiotic administrat...

  17. VAR Methodology Used for Exchange Risk Measurement and Prevention

    Directory of Open Access Journals (Sweden)

    Florentina Balu

    2006-05-01

    Full Text Available In this article we discuss one of the modern risk measuring techniques Value-at-Risk (VaR. Currently central banks in major money centers, under the auspices of the BIS Basle Committee, adopt the VaR system to evaluate the market risk of their supervised banks. Banks regulators ask all commercial banks to report VaRs with their internal models. Value at risk (VaR is a powerful tool for assessing market risk, but it also imposes a challenge. Its power is its generality. Unlike market risk metrics such as the Greeks, duration and convexity, or beta, which are applicable to only certain asset categories or certain sources of market risk, VaR is general. It is based on the probability distribution for a portfolio’s market value. Value at Risk (VAR calculates the maximum loss expected (or worst case scenario on an investment, over a given time period and given a specified degree of confidence. There are three methods by which VaR can be calculated: the historical simulation, the variance-covariance method and the Monte Carlo simulation. The variance-covariance method is easiest because you need to estimate only two factors: average return and standard deviation. However, it assumes returns are well-behaved according to the symmetrical normal curve and that historical patterns will repeat into the future. The historical simulation improves on the accuracy of the VAR calculation, but requires more computational data; it also assumes that “past is prologue”. The Monte Carlo simulation is complex, but has the advantage of allowing users to tailor ideas about future patterns that depart from historical patterns.

  18. VAR Methodology Used for Exchange Risk Measurement and Prevention

    Directory of Open Access Journals (Sweden)

    Ion Stancu

    2006-03-01

    Full Text Available In this article we discuss one of the modern risk measuring techniques Value-at-Risk (VaR. Currently central banks in major money centers, under the auspices of the BIS Basle Committee, adopt the VaR system to evaluate the market risk of their supervised banks. Banks regulators ask all commercial banks to report VaRs with their internal models. Value at risk (VaR is a powerful tool for assessing market risk, but it also imposes a challenge. Its power is its generality. Unlike market risk metrics such as the Greeks, duration and convexity, or beta, which are applicable to only certain asset categories or certain sources of market risk, VaR is general. It is based on the probability distribution for a portfolio’s market value. Value at Risk (VAR calculates the maximum loss expected (or worst case scenario on an investment, over a given time period and given a specified degree of confidence. There are three methods by which VaR can be calculated: the historical simulation, the variance-covariance method and the Monte Carlo simulation. The variance-covariance method is easiest because you need to estimate only two factors: average return and standard deviation. However, it assumes returns are well-behaved according to the symmetrical normal curve and that historical patterns will repeat into the future. The historical simulation improves on the accuracy of the VAR calculation, but requires more computational data; it also assumes that “past is prologue”. The Monte Carlo simulation is complex, but has the advantage of allowing users to tailor ideas about future patterns that depart from historical patterns.

  19. Clinical profile of parkinson's disease: Experience of niger

    Directory of Open Access Journals (Sweden)

    Hamid Assadeck

    2018-01-01

    Full Text Available Background: Parkinson's disease (PD is a chronic neurodegenerative pathology with unknown etiology. It is characterized clinically by the classic triad that associated tremors, bradykinesia, and rigidity. In Niger, there are no data on PD. Aims: We aimed to provide the demographic and clinical profile of PD in patients from Niger to create a database on PD in Niger. Patients and Methods: We conducted a retrospective study at the Neurology Outpatient Clinic of the Hôpital National de Niamey (HNN, Niger over a period of 4.42 years from February 2009 to July 2013 collecting all cases of PD. The demographic and clinical features of all patients were collected and analyzed. Results: During the period of the study, 1695 patients consulted at the Neurology Outpatient Clinic of the HNN, among which 76 patients (4.48% had secondary parkinsonism and 25 patients (1.47% had features compatible with PD. Only patients with PD were included in this study. The mean age at onset of symptoms was 58 years (range: 42–74 years. The male sex was predominant (60% with a sex ratio of 1.5. The mean time interval from the onset of symptoms to diagnosis of PD was 1.8 years (range: 1–5 years. The tremor was the most common symptom (84%. Bradykinesia represented 64% of the symptoms and rigidity 20%. At the time of the diagnosis of PD, 8 patients (32% were in Stage I of the classification of Hoehn and Yahr, 16 patients (64% in Stage II, and 1 patient (4% in Stage III. The levodopa/carbidopa combination was the most used antiparkinsonian drug in our patients (88%. The mean time of follow-up of the patients was 2.5 years (range: 1–4.42 years. During the course of the disease, 9 patients (36% were in Stage II of the classification of Hoehn and Yahr, 13 patients (52% in Stage III, and 3 patients (12% in Stage IV. Conclusion: Our study provides demographic and clinical data of PD in patients from Niger and shows that the hospital frequency of this disease is low (1

  20. DECONTAMINATION ASSESSMENT OF BACILLUS ANTHRACIS, BACILLUS SUBTILIS, AND GEOBACILLUS STEAROTHERMOPHILUS SPORES ON INDOOR SURFACTS USING A HYDROGEN PERIOXIDE GAS GENERATOR

    Science.gov (United States)

    Aims: To evaluate the decontamination of Bacillus anthracis, Bacillus subtilis, and Geobacillus stearothermophilus spores on indoor surface materials using hydrogen peroxide gas. Methods and Results: B. anthracis, B. subtilis, and G. Stearothermophilus spores were dried on seven...

  1. Genetic analisys of a cross of gaillon (Brassica oleracea var. alboglabra) with cauliflower (B.oleracea var. botrytis)

    OpenAIRE

    Spini, Vanessa B.M.G.; Kerr, Warwick Estevam

    2000-01-01

    The cauliflower (Brassica oleracea var. botrytis) is an annual vegetable cultivated in Southern and Southwestern Brazil with limited production in the Northeast and Centralwest. A variety of Chinese kale, "kaai laan" or "gaillon" (Brassica oleracea var. alboglabra), produces seeds at high temperatures and therefore can do so in North and Northeastern Brazil. Gaillon and cauliflower were crossed 55 times using 10 gaillon plants as mothers and 4 cauliflower plants as pollen donors. From these c...

  2. Characterization of the Aspergillus niger prtT, a unique regulator of extracellular protease encoding genes

    NARCIS (Netherlands)

    Punt, P.J.; Schuren, F.H.J.; Lehmbeck, J.; Christensen, T.; Hjort, C.; Hondel, C.A.M.J.J. van den

    2008-01-01

    Expression of several Aspergillus niger genes encoding major secreted, but not vacuolar, protease genes including the major acid protease gene pepA, was shown to be affected in the previously isolated A. niger protease mutant, AB1.13 [Mattern, I.E., van Noort, J.M., van den Berg, P., Archer, D.A.,

  3. D-Galactose uptake is nonfunctional in the conidiospores of Aspergillus niger

    NARCIS (Netherlands)

    Fekete, E.; de Vries, R.P.; Seiboth, B.; vanKuyk, P.A.; Sandor, E.; Metz, B.; Kubicek, C.P.; Karaffa, L.

    2012-01-01

    The majority of black Aspergilli (Aspergillus section Nigri), including Aspergillus niger, as well as many other Ascomycetes fail to germinate on d-galactose as a sole carbon source. Here, we provide evidence that the ability of A. niger to transport d-galactose is growth stage dependent, being

  4. Corporate Social Responsibility: Case Study of Community Expectations and the Administrative Systems, Niger Delta

    Science.gov (United States)

    Ogula, David

    2012-01-01

    Poor community-company relations in the Niger Delta have drawn attention to the practice of corporate social responsibility (CSR) in the region. Since the 1960s, transnational oil corporations operating in the Niger Delta have adopted various CSR strategies, yet community-company relations remain adversarial. This article examines community…

  5. Assessment of the pectinolytic network of Aspergillus niger by functional genomics : insights from the transcriptome

    NARCIS (Netherlands)

    Martens-Uzunova, E.S.

    2008-01-01

    More than a century ago, in 1889, A. Fernbach presented a detailed report about the invertase of Aspergillus niger in the third edition of “Annales De L'institut Pasteur”. Since then, many of the enzymes secreted by A. niger have found a broad range of applications, and today they are produced on an

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

    NARCIS (Netherlands)

    Yuan, Xiao-Lian

    2008-01-01

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

  7. An Over-View of Niger Delta Indigenous Religion | Tasie | Lwati: A ...

    African Journals Online (AJOL)

    This essay is an outline and interpretation of Niger Delta indigenous religion. It examines the structure of the indigenous religion and points out that as heterogeneous and diverse as the people of Niger Delta are, so also is the indigenous religion of the people. Thus, an ethnic group may emphasize a belief system or an ...

  8. Quantitative iTRAQ secretome analysis of aspergillus niger reveals novel hydrolytic enzymes

    NARCIS (Netherlands)

    Adav, S.S.; Li, A.A.; Manavalan, A.; Punt, P.; Sze, S.K.

    2010-01-01

    The natural lifestyle of Aspergillus niger made them more effective secretors of hydrolytic proteins and becomes critical when this species were exploited as hosts for the commercial secretion of heterologous proteins. The protein secretion profile of A. niger and its mutant at different pH was

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

    DEFF Research Database (Denmark)

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

    2007-01-01

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

  10. Development of ferry service on the lower Niger, 1901-1960 | Ali ...

    African Journals Online (AJOL)

    The paper demonstrates colonial government efforts in developing water transportation on the Lower Niger River by maintaining vessels as vehicles of transportation from the beginning of the twentieth century. Government departments were set up at various times to oversee activities of users of the River Niger.

  11. Cytosolic streaming in vegetative mycelium and aerial structures of aspergillus niger

    NARCIS (Netherlands)

    Bleichrodt, R.; Vinck, A.; Krijgsheld, P.; van Leeuwen, M.R.; Dijksterhuis, J.; Wösten, H.A.B.

    2013-01-01

    Aspergillus niger forms aerial hyphae and conidiophores after a period of vegetative growth. The hyphae within the mycelium of A. niger are divided by septa. The central pore in these septa allows for cytoplasmic streaming. Here, we studied inter- and intra-compartmental streaming of the reporter

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

    NARCIS (Netherlands)

    Pel, Herman J.; de Winde, Johannes H.; Archer, David B.; Dyer, Paul S.; Hofmann, Gerald; Schaap, Peter J.; Turner, Geoffrey; Albang, Richard; Albermann, Kaj; Andersen, Mikael R.; Bendtsen, Jannick D.; Benen, Jacques A. E.; van den Berg, Marco; Breestraat, Stefaan; Caddick, Mark X.; Contreras, Roland; Cornell, Michael; Coutinho, Pedro M.; Danchin, Etienne G. J.; Debets, Alfons J. M.; Dekker, Peter; van Dijck, Piet W. M.; van Dijk, Alard; Dijkhuizen, Lubbert; Driessen, Arnold J. M.; d'Enfert, Christophe; Geysens, Steven; Groot, Gert S. P.; de Groot, Piet W. J.; Guillemette, Thomas; Henrissat, Bernard; Herweijer, Marga; van den Hombergh, Johannes P. T. W.; van den Hondel, Cees A. M. J. J.; van der Heijden, Rene T. J. M.; van der Kaaij, Rachel M.; Klis, Frans M.; Kools, Harrie J.; Kubicek, Christian P.; van Kuyk, Patricia A.; Lauber, Juergen; Lu, Xin; van der Maarel, Marc J. E. C.; Meulenberg, Rogier; Menke, Hildegard; Mortimer, Martin A.; Nielsen, Jens; Oliver, Stephen G.; Olsthoorn, Maurien; Pal, Karoly; van Peij, Noel N. M. E.; Ram, Arthur F. J.; Rinas, Ursula; Roubos, Johannes A.; Sagt, Cees M. J.; Schmoll, Monika; Sun, Jibin; Ussery, David; Varga, Janos; Vervecken, Wouter; de Vondervoort, Peter J. J. van; Wedler, Holger; Wosten, Han A. B.; Zeng, An-Ping; van Ooyen, Albert J. J.; Visser, Jaap; Stam, Hein; Enfert, Christophe d’; Lauber, Jürgen; Goosen, Coenie; de Vries, Ronald P.

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

  13. Phosphatases modulate the bistable sporulation gene expression pattern in Bacillus subtilis

    NARCIS (Netherlands)

    Veening, JW; Hamoen, LW; Kuipers, OP

    Spore formation in the Gram- positive bacterium Bacillus subtilis is a last resort adaptive response to starvation. To initiate sporulation, the key regulator in this process, Spo0A, needs to be activated by the so-called phosphorelay. Within a sporulating culture of B. subtilis, some cells initiate

  14. Plant methyl salicylate induces defense responses in the rhizobacterium Bacillus subtilis.

    Science.gov (United States)

    Kobayashi, Kazuo

    2015-04-01

    Bacillus subtilis is a rhizobacterium that promotes plant growth and health. Cultivation of B. subtilis with an uprooted weed on solid medium produced pleat-like architectures on colonies near the plant. To test whether plants emit signals that affect B. subtilis colony morphology, we examined the effect of plant-related compounds on colony morphology. Bacillus subtilis formed mucoid colonies specifically in response to methyl salicylate, which is a plant-defense signal released in response to pathogen infection. Methyl salicylate induced mucoid colony formation by stimulating poly-γ-glutamic acid biosynthesis, which formed enclosing capsules that protected the cells from exposure to antimicrobial compounds. Poly-γ-glutamic acid synthesis depended on the DegS-DegU two-component regulatory system, which activated DegSU-dependent gene transcription in response to methyl salicylate. Bacillus subtilis did not induce plant methyl salicylate production, indicating that the most probable source of methyl salicylate in the rhizosphere is pathogen-infected plants. Methyl salicylate induced B. subtilis biosynthesis of the antibiotics bacilysin and fengycin, the latter of which exhibited inhibitory activity against the plant pathogenic fungus Fusarium oxysporum. We propose that B. subtilis may sense plants under pathogen attack via methyl salicylate, and express defense responses that protect both B. subtilis and host plants in the rhizosphere. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  15. 75 FR 862 - Bacillus subtilis; Registration Review Proposed Decision; Notice of Availability

    Science.gov (United States)

    2010-01-06

    ...: Bacillus subtilis strain GB03 is used to prevent, control and suppress plant disease on barley, berries, bulb vegetables, cole crops, cotton, cucurbits, fruiting vegetables, herbs, leafy crops, legumes... subtilis strain MBI 600 is used to suppress disease organisms such as Botrytis, Alternaria, Rhizoctonia...

  16. Engineering the Xylan Utilization System in Bacillus subtilis for Production of Acidic Xylooligosaccharides

    Science.gov (United States)

    Mun Su Rhee; Lusha Wei; Neha Sawhney; John D. Rice; Franz J. St. John; Jason C. Hurlbert; James F. Preston

    2014-01-01

    Xylans are the predominant polysaccharides in hemicelluloses and an important potential source of biofuels and chemicals. The ability of Bacillus subtilis subsp. subtilis strain 168 to utilize xylans has been ascribed to secreted glycoside hydrolase family 11 (GH11) and GH30 endoxylanases, encoded by the xynA and...

  17. Genomic comparisons of two Bacillus subtilis biocontrol strains with different modes of actions

    Science.gov (United States)

    Bacillus subtilis strains AS 43.3 and OH131.1 were isolated from wheat anthers and shown to be efficacious in managing Fusarium head blight in greenhouse and some field trials. Chemical analysis of the cell-free culture supernatant identified B. subtilis strain AS 43.3 to be a potent producer of the...

  18. Genetic or chemical protease inhibition causes significant changes in the Bacillus subtilis exoproteome

    NARCIS (Netherlands)

    Westers, Lidia; Westers, Helga; Zanen, Geeske; Antelmann, Haike; Hecker, Michael; Noone, David; Devine, Kevin M.; van Dijl, Jan Maarten; Quax, Wim J.

    Bacillus subtilis is a prolific producer of enzymes and biopharmaceuticals. However, the susceptibility of heterologous proteins to degradation by (extracellular) proteases is a major limitation for use of B. subtilis as a protein cell factory. An increase in protein production levels has previously

  19. Cell Physiology and Protein Secretion of Bacillus licheniformis Compared to Bacillus subtilis

    NARCIS (Netherlands)

    Voigt, Birgit; Antelmann, Haike; Albrecht, Dirk; Ehrenreich, Armin; Maurer, Karl-Heinz; Evers, Stefan; Gottschalk, Gerhard; van Dijl, Jan Maarten; Schweder, Thomas; Hecker, Michael

    2009-01-01

    The genome sequence of Bacillus subtilis was published in 1997 and since then many other bacterial genomes have been sequenced, among them Bacillus licheniformis in 2004. B. subtilis and B. licheniformis are closely related and feature similar saprophytic lifestyles in the soil. Both species can

  20. Towards a complete proteome of Bacillus subtilis : cytosolic, cell wall-associated and extracellular proteins

    NARCIS (Netherlands)

    Antelmann, Haike; van Dijl, Jan Maarten; Hecker, Michael

    2003-01-01

    Bacillus subtilis is widely regarded as a model organism for the functional genome analysis of Gram-positive bacteria. This is based on two factors: first, the genome sequence that predicts about 4100 open reading frames was completed in 1997 (1) and second, B. subtilis strain 168 is highly amenable

  1. Effect of Bacillus subtilis natto on growth performance in Muscovy ducks

    Directory of Open Access Journals (Sweden)

    T Sheng-Qiu

    2013-09-01

    Full Text Available The aim of the present study was to determine whether dietary Bacillus subtilis natto could affect growth performance of Muscovy ducks. A total of 120 hundred Muscovy ducks at the age of 1 day were randomly assigned to four groups (30 Muscovy ducks/group, and fed with diets supplemented with 0% (control group, 0.1%, 0.2%, and 0.4% Bacillus subtilis natto, respectively during the 6-week feeding period. Weight gain, feed intake and feed conversion efficiency of Muscovy ducks were significantly improved by the dietary addition of Bacillus subtilis natto, and the results were more significant in 0.4% dietary Bacillus subtilis natto treatment group; Also, Bacillus subtilis natto reduced Escherichia coli and Salmonella colonies, and increased lactobacilli population in the ileum and the cecum. Biochemical parameters, including total protein, GOT (glutamic oxaloacetic transaminase, GPT (glutamic pyruvic transaminase, AKP (alkaline phosphatase, triiodothyronine (T3 and tetraiodothyronine (T4 contents (pBacillus subtilis natto was added to the diets (p0.05. The results of the present study indicate that diets with 0.4% Bacillus subtilis natto improved the growth performance of Muscovy ducks by increasing the absorption of protein, simulating hormone secretion, suppressing harmful microflora, and improving the duodenal structure and immune functions of Muscovy ducks. It is suggested that Bacillus subtilis natto is a potential candidate to be used use as a probiotic to improve the growth performance of Muscovy ducks.

  2. Effect of Bacillus subtilis on the growth and survival rate of shrimp ...

    African Journals Online (AJOL)

    The effect ofBacillus subtilis, isolated from digestive tract of Macrobrachium rosenbergii was investigated on growth and survival rate of Litopenaeus vannamei during 60 days of culture. Sixteen aquaria with four replicates were used for treatments and controls. Treatment groups were consisted of Bacillus subtilis, isolated ...

  3. 40 CFR 180.1209 - Bacillus subtilis strain QST 713; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus subtilis strain QST 713... RESIDUES IN FOOD Exemptions From Tolerances § 180.1209 Bacillus subtilis strain QST 713; exemption from the... the microbial pesticide Bacillus subtilis strain QST 713 when used in or on all food commodities. [65...

  4. GLYCOGEN IN BACILLUS-SUBTILIS - MOLECULAR CHARACTERIZATION OF AN OPERON ENCODING ENZYMES INVOLVED IN GLYCOGEN BIOSYNTHESIS AND DEGRADATION

    NARCIS (Netherlands)

    KIEL, JAKW; BOELS, JM; BELDMAN, G; VENEMA, G

    Although it has never been reported that Bacillus subtilis is capable of accumulating glycogen, we have isolated a region from the chromosome of B. subtilis containing a glycogen operon. The operon is located directly downstream from trnB, which maps at 275 degrees on the B. subtilis chromosome. It

  5. Selection of tannase-producing Aspergillus niger strains Seleção de linhagens de Aspergillus niger produtoras de tanase

    Directory of Open Access Journals (Sweden)

    Gustavo A.S. Pinto

    2001-03-01

    Full Text Available The aim of this work was to select strains of Aspergillus niger for tannase production. Growth of colonies in plates with tannic acid-containing medium indicated their ability to synthesize tannase. Tannase activity was also measured in solid-state fermentation. A. niger 11T25A5 was the best tannase producer (67.5 U.g-1/72 hours of fermentation.O objetivo deste trabalho foi selecionar linhagens de Aspergillus niger para síntese de tanase. O crescimento das colônias em meio contendo ácido tânico indicou capacidade de produção de tanase. A atividade enzimática foi determinada em fermentação semi-sólida. A. niger 11T25A5 foi o melhor produtor (67.5 U.g-1/72 horas de fermentação.

  6. A refined estimate of the malaria burden in Niger

    Directory of Open Access Journals (Sweden)

    Doudou Maimouna

    2012-03-01

    Full Text Available Abstract Background The health authorities of Niger have implemented several malaria prevention and control programmes in recent years. These interventions broadly follow WHO guidelines and international recommendations and are based on interventions that have proved successful in other parts of Africa. Most performance indicators are satisfactory but, paradoxically, despite the mobilization of considerable human and financial resources, the malaria-fighting programme in Niger seems to have stalled, as it has not yet yielded the expected significant decrease in malaria burden. Indeed, the number of malaria cases reported by the National Health Information System has actually increased by a factor of five over the last decade, from about 600,000 in 2000 to about 3,000,000 in 2010. One of the weaknesses of the national reporting system is that the recording of malaria cases is still based on a presumptive diagnosis approach, which overestimates malaria incidence. Methods An extensive nationwide survey was carried out to determine by microscopy and RDT testing, the proportion of febrile patients consulting at health facilities for suspected malaria actually suffering from the disease, as a means of assessing the magnitude of this problem and obtaining a better estimate of malaria morbidity in Niger. Results In total, 12,576 febrile patients were included in this study; 57% of the slides analysed were positive for the malaria parasite during the rainy season, when transmission rates are high, and 9% of the slides analysed were positive during the dry season, when transmission rates are lower. The replacement of microscopy methods by rapid diagnostic tests resulted in an even lower rate of confirmation, with only 42% of cases testing positive during the rainy season, and 4% during the dry season. Fever alone has a low predictive value, with a low specificity and sensitivity. These data highlight the absolute necessity of confirming all reported

  7. Menaquinone and iron are essential for complex colony development in Bacillus subtilis.

    Directory of Open Access Journals (Sweden)

    Gidi Pelchovich

    Full Text Available Cells of undomesticated species of Bacillus subtilis frequently form complex colonies during spreading on agar surfaces. Given that menaquinone is involved in another form of coordinated behavior, namely, sporulation, we looked for a possible role for menaquinone in complex colony development (CCD in the B. subtilis strain NCIB 3610. Here we show that inhibition of menaquinone biosynthesis in B. subtilis indeed abolished its ability to develop complex colonies. Additionally some mutations of B. subtilis which confer defective CCD could be suppressed by menaquinone derivatives. Several such mutants mapped to the dhb operon encoding the genes responsible for the biosynthesis of the iron siderophore, bacillibactin. Our results demonstrate that both menaquinone and iron are essential for CCD in B. subtilis.

  8. Bacillus subtilis biofilm extends Caenorhabditis elegans longevity through downregulation of the insulin-like signalling pathway

    Science.gov (United States)

    Donato, Verónica; Ayala, Facundo Rodríguez; Cogliati, Sebastián; Bauman, Carlos; Costa, Juan Gabriel; Leñini, Cecilia; Grau, Roberto

    2017-01-01

    Beneficial bacteria have been shown to affect host longevity, but the molecular mechanisms mediating such effects remain largely unclear. Here we show that formation of Bacillus subtilis biofilms increases Caenorhabditis elegans lifespan. Biofilm-proficient B. subtilis colonizes the C. elegans gut and extends worm lifespan more than biofilm-deficient isogenic strains. Two molecules produced by B. subtilis — the quorum-sensing pentapeptide CSF and nitric oxide (NO) — are sufficient to extend C. elegans longevity. When B. subtilis is cultured under biofilm-supporting conditions, the synthesis of NO and CSF is increased in comparison with their production under planktonic growth conditions. We further show that the prolongevity effect of B. subtilis biofilms depends on the DAF-2/DAF-16/HSF-1 signalling axis and the downregulation of the insulin-like signalling (ILS) pathway. PMID:28134244

  9. Acid and base stress and transcriptomic responses in Bacillus subtilis.

    Science.gov (United States)

    Wilks, Jessica C; Kitko, Ryan D; Cleeton, Sarah H; Lee, Grace E; Ugwu, Chinagozi S; Jones, Brian D; BonDurant, Sandra S; Slonczewski, Joan L

    2009-02-01

    Acid and base environmental stress responses were investigated in Bacillus subtilis. B. subtilis AG174 cultures in buffered potassium-modified Luria broth were switched from pH 8.5 to pH 6.0 and recovered growth rapidly, whereas cultures switched from pH 6.0 to pH 8.5 showed a long lag time. Log-phase cultures at pH 6.0 survived 60 to 100% at pH 4.5, whereas cells grown at pH 7.0 survived base induced adaptation to a more extreme acid or base, respectively. Expression indices from Affymetrix chip hybridization were obtained for 4,095 protein-encoding open reading frames of B. subtilis grown at external pH 6, pH 7, and pH 9. Growth at pH 6 upregulated acetoin production (alsDS), dehydrogenases (adhA, ald, fdhD, and gabD), and decarboxylases (psd and speA). Acid upregulated malate metabolism (maeN), metal export (czcDO and cadA), oxidative stress (catalase katA; OYE family namA), and the SigX extracytoplasmic stress regulon. Growth at pH 9 upregulated arginine catabolism (roc), which generates organic acids, glutamate synthase (gltAB), polyamine acetylation and transport (blt), the K(+)/H(+) antiporter (yhaTU), and cytochrome oxidoreductases (cyd, ctaACE, and qcrC). The SigH, SigL, and SigW regulons were upregulated at high pH. Overall, greater genetic adaptation was seen at pH 9 than at pH 6, which may explain the lag time required for growth shift to high pH. Low external pH favored dehydrogenases and decarboxylases that may consume acids and generate basic amines, whereas high external pH favored catabolism-generating acids.

  10. Pharmacognostical and phytochemical studies of Helleborus niger L root

    Directory of Open Access Journals (Sweden)

    V Kishor Kumar

    2017-01-01

    Full Text Available Background: Helleborus niger L (Ranunculaceae is used Ayurvedic and Unani systems and other herbal medicine systems. The roots of H. niger have a good medicinal value. Aims: To conduct a pharmacognostical and phytochemical study of H. niger. Materials and Methods: The pharmacognostical studies on roots including parameters such as taxonomical, macroscopic, microscopic characters, physico-chemical, ultra-violet analysis and phytochemical studies are established. Results: Macroscopically, the roots are brownish-black in colour, cylindrical in shape, feeble odour, slightly acrid taste with irregularly branched. Microscopically the root showed the presence of epidermis, air-chambers, fissure periderm, periderm, inner cortex, pith, phloem, xylem, vessels and xylem vessels. Microscopic examination of the powder showed the presence of parenchyma cells, parenchyma mass, periderm, cell inclusion, laticifer, lateral wall pith, perforation, xylem bundle and xylem elements. Ultra-violet and ordinary light analyses with different reagents were conducted to identify the drug in powder form. Physico-chemical evaluation established, Ash values - Total, acid insoluble, water soluble and sulphated ash values were 7.3%, 4.1%, 3.7% and 5.2%, respectively. Extractive values - Alcohol soluble, water soluble and ether soluble extractive values were 22.8%, 7.4% and 5.6%, respectively. Loss on drying was 3.3%. Preliminary phytochemical screening showed the presence of carbohydrate, glycoside, saponins, flavonoid, phytosterols, tannins and phenolic compounds. Conclusions: The results of the study can serve as a valuable resource of pharmacognostic and phytochemical information. This will serve as appropriate, standards for discovery of this plant material in future investigations and applications and also contribute towards establishing pharmacopoeial standards.

  11. Functional Diversity of AAA+ Protease Complexes in Bacillus subtilis.

    Science.gov (United States)

    Elsholz, Alexander K W; Birk, Marlene S; Charpentier, Emmanuelle; Turgay, Kürşad

    2017-01-01

    Here, we review the diverse roles and functions of AAA+ protease complexes in protein homeostasis, control of stress response and cellular development pathways by regulatory and general proteolysis in the Gram-positive model organism Bacillus subtilis . We discuss in detail the intricate involvement of AAA+ protein complexes in controlling sporulation, the heat shock response and the role of adaptor proteins in these processes. The investigation of these protein complexes and their adaptor proteins has revealed their relevance for Gram-positive pathogens and their potential as targets for new antibiotics.

  12. Synthesis of acid-soluble spore proteins by Bacillus subtilis.

    OpenAIRE

    Leventhal, J M; Chambliss, G H

    1982-01-01

    The major acid-soluble spore proteins (ASSPs) of Bacillus subtilis were detected by immunoprecipitation of radioactively labeled in vitro- and in vivo-synthesized proteins. ASSP synthesis in vivo began 2 h after the initiation of sporulation (t2) and reached its maximum rate at t7. This corresponded to the time of synthesis of mRNA that stimulated the maximum rate of ASSP synthesis in vitro. Under the set of conditions used in these experiments, protease synthesis began near t0, alkaline phos...

  13. Functional Diversity of AAA+ Protease Complexes in Bacillus subtilis

    Science.gov (United States)

    Elsholz, Alexander K. W.; Birk, Marlene S.; Charpentier, Emmanuelle; Turgay, Kürşad

    2017-01-01

    Here, we review the diverse roles and functions of AAA+ protease complexes in protein homeostasis, control of stress response and cellular development pathways by regulatory and general proteolysis in the Gram-positive model organism Bacillus subtilis. We discuss in detail the intricate involvement of AAA+ protein complexes in controlling sporulation, the heat shock response and the role of adaptor proteins in these processes. The investigation of these protein complexes and their adaptor proteins has revealed their relevance for Gram-positive pathogens and their potential as targets for new antibiotics. PMID:28748186

  14. Higher antibiotic yielding mutants of bacillus subtilis by gamma radiation

    International Nuclear Information System (INIS)

    Ahmad, M.S.; Shaukat, G.A.; Malik, M.A.

    1987-01-01

    When Bacillus Subtilis AECL69 was grown in malt extract-pepetone-molasses-sugar (MPMS) medium, it could produce antibiotic substance(s) with antibacterial and antifungal properties in the culture fluid. The bacterial cells grown in MPMS medium were washed and suspended into distilled water and irradiated with gamma rays in Gammacell 220 at different doses. Higher antibiotic yielding isolates (plus mutants) were obtained from cell pollutions irradiated at 15 Kr. These gamma rays-induced plus mutants showed simultaneous higher production of antibacterial as well as antifungal activity. (author)

  15. Hyper production of alkaline protease by mutagenized bacillus subtilis

    International Nuclear Information System (INIS)

    Qureshi, A.M.; Tanseem, F.

    2010-01-01

    The purpose of this work was to augment the alkaline protease production from Bacillus subtilis by using chemical mutagen (MMS) and UV mutagenesis. A number of mutants were isolated which produce high levels of extra cellular proteases. Analysis of culture supernatants of these mutants had shown that the total amounts of proteolysis activity were increased from 1 to 2 fold over the wild strain. Clones showing promote response were further characterized by analyzing different parameters; like of Temperature, pH substrate concentration and incubation period, to study the activity of protease enzyme. (author)

  16. Sticking together: building a biofilm the Bacillus subtilis way

    Science.gov (United States)

    Vlamakis, Hera; Chai, Yunrong; Beauregard, Pascale; Losick, Richard; Kolter, Roberto

    2014-01-01

    Preface Biofilms are ubiquitous communities of tightly associated bacteria encased in an extracellular matrix. Bacillus subtilis has long-served as a robust model organism to examine the molecular mechanisms of biofilm formation and a number of studies have revealed that this process is subject to a number of integrated regulatory pathways. In this Review, we focus on the molecular mechanisms controlling biofilm assembly and briefly summarize the current state of knowledge regarding their disassembly. We also discuss recent progress that has expanded our understanding of biofilm formation on plant roots, which are a natural habitat for this soil bacterium. PMID:23353768

  17. Bacterial determinants of the social behavior of Bacillus subtilis.

    Science.gov (United States)

    Romero, Diego

    2013-09-01

    Bacteria utilize sophisticated cellular machinery to sense environmental changes and coordinate the most appropriate response. Fine sensors located on cell surfaces recognize a myriad of triggers and initiate genetic cascades leading to activation or repression of certain groups of genes. Structural elements such as pilli, exopolysaccharides and flagella are also exposed at the cell surface and contribute to modulating the intimate interaction with surfaces and host cells. This review will cover the latest advances in our understanding of the biology and functionality of these bacterial determinants within the context of biofilm formation of Bacillus subtilis. Copyright © 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  18. Production and applications of biosurfactant from Bacillus subtilis MUV4

    Directory of Open Access Journals (Sweden)

    Aran H-Kittikun

    2008-04-01

    Full Text Available Bacillus subtilis MUV4 produced biosurfactant in shake-flask culture (200 rpm at 30oC with modified Mckeen medium containing 1% glucose as a carbon source, 1% monosodium glutamate and 0.3% yeast extract as nitrogen sources. The supernatant of B. subtilis MUV4 reduced the surface tension of the medium from 53.50 mN/m to 33.50 mN/m after 48 h of cultivation. The yield of crude biosurfactant from B. subtilis MUV4 after precipitating the supernatant with 6N HCl was 0.652 g/L. Growth kinetics studies showed the specific growth rate (μ of 0.14 h-1, yield of biomass to substrate (Yx/s of 0.713, yield of product to substrate (Yp/s of 0.072 and yield of product to biomass (Yp/x of 0.101. Moreover, B. subtilis MUV4 produced 0.30 g/L crude biosurfactant after 96 h of cultivation in the fermentor with agitation rate of 200 rpm without aeration and uncontrolled pH condition. The crude biosurfactant was dissolved in methanol and dried by vacuum evaporator (crude methanol. The supernatant, the crude biosurfactant and the crude methanol retained the biosurfactant activity over the pH range of 1-6, 7-10 and 4-10, respectively and the emulsion stability at 24 h (E24 at pH 7 were 66.67%, 33.33% and 33.33%, respectively. The supernatant and the crude biosurfactant showed surface tension activity at 4oC, room temperature (30±2oC and 50oC after incubation for 5 h. However, only crude methanol still retained surface tension activity after 100oC for 5 h. The surface tension activity of the supernatant and the crude biosurfactant was stable in 3-10% (w/v NaCl while crude methanol showed stability in 3-20% (w/v NaCl. However, all samples lost emulsion stability when NaCl concentration was higher than 5% (w/v. With sand pack column technique, crude methanol enhanced the recovery of crude oil and kerosene oil by 41.85% and 75.00%, respectively. In hydrocarbon degradation application study, the crude biosurfactant was added to the culture medium containing 0.3% crude oil

  19. HPLC Quantification of Cytotoxic Compounds from Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Paula Karina S. Uchoa

    2017-01-01

    Full Text Available A high-performance liquid chromatography method was developed and validated for the quantification of the cytotoxic compounds produced by a marine strain of Aspergillus niger. The fungus was grown in malt peptone dextrose (MPD, potato dextrose yeast (PDY, and mannitol peptone yeast (MnPY media during 7, 14, 21, and 28 days, and the natural products were identified by standard compounds. The validation parameters obtained were selectivity, linearity (coefficient of correlation > 0.99, precision (relative standard deviation below 5%, and accuracy (recovery > 96.

  20. Steady-state shear characteristics of Aspergillus niger broths

    Energy Technology Data Exchange (ETDEWEB)

    Svihla, C.K.; Dronawat, S.N.; Hanley, T.R. [Univ. of Louisville, KY (United States)

    1995-12-31

    It can be difficult to obtain reliable rheological data for filamentous fermentation broths using conventional instruments. One common approach is to measure the torque drawn by an impeller rotating in the suspension. Many previous workers have assumed that the applicable shear rate in such a device is related to the impeller speed by a fluid-independent constant determined by calibration with Newtonian and non-Newtonian fluids. The rheology of Aspergillus niger broths have been characterized using the impeller viscometer approach. The changes in the broth rheology were measured, and used to interpret the growth of biomass and the evolution of the microorganism morphology.

  1. Social Licensing in the Uranium Cycle Production (Case of Niger)

    Energy Technology Data Exchange (ETDEWEB)

    Dari, A., E-mail: dariayouba@yahoo.fr [Ministry of Mining and Energy, Mines Direction/DEM, Niamey (Niger)

    2014-05-15

    In Niger Republic, uranium exploitation has begun since 1970. It is an economic resource but also causes social and environmental problems. To exploit according to the rule, to protect social environment, to work in safe conditions and contribute to the development of local population one side and Niger Republic in the other side, a mining law was voted in March 1993. It is about the ordinance n°93-16 on mining law which was modified in August 2006 by a new mining law, the ordinance n°2006-26 of 9 August 2006. As well as the presidential decree affecting the application of this new law was issued. Other legislative and regulatory texts have been taken as far as exploration and exploitation mining. For example, the mining agreement, the order n°0073/PM of 4 July 2005 relative to the transparency on mining exploitation; ordinance n°97-001 of 10 January 1997 appointing the environmental studying impact and the law 98–56 of 29 December 1998 relative to the management of environment. For acquisition of an exploration licence or a mining licence, a mining agreement is signed between the mining company and Niger Republic which makes clear social, environmental, financial, and economic conditions in which the mining company must exploit natural resources. The ordinance n°93-16 of 2 March 1993 related to the mining law in chapter IV, clarifies conditions for acquisition of exploration and mining licence in Niger Republic. It clarifies again in the same chapter, title VI, rights and obligations relating to mine or quarry operations for companies and tax provisions relative those activities. In the same order, in title VIII, hygiene and security conditions in mines are been specified. The mining agreement in title IV, specify rights, obligations and administration in mining activities, particularly article 18.2 which stipulates “the mining company undertakes to contribute to the development of municipalities in which it shall carry out activities, by contributing to

  2. An appraisal of river erosion mitigation in the Niger Delta

    International Nuclear Information System (INIS)

    Aban, T. K. S.; Omuso, W. O.

    1999-01-01

    River erosion processes in the Niger Delta and the effectiveness of locally applied remedial measures is appraised, using information on channel geometry, flow velocity distribution, soil type, stratification, bank height and steepness, state of compaction, together with pool level variation in river channels. High flow velocity and bank height were identified as the major erosion causative factors. Local responses towards erosion mitigation have involved structural methods to varying degree of success. River training has been recommended as a long - term regional approach to mitigate river bank erosion. However, in the short -term revetments, concrete and sheets piles may be applied cautiously

  3. Some tests for parameter constancy in cointegrated VAR-models

    DEFF Research Database (Denmark)

    Hansen, Henrik; Johansen, Søren

    1999-01-01

    Some methods for the evaluation of parameter constancy in vector autoregressive (VAR) models are discussed. Two different ways of re-estimating the VAR model are proposed; one in which all parameters are estimated recursively based upon the likelihood function for the first observations, and anot...... be applied to test the constancy of the long-run parameters in the cointegrated VAR-model. All results are illustrated using a model for the term structure of interest rates on US Treasury securities. ......Some methods for the evaluation of parameter constancy in vector autoregressive (VAR) models are discussed. Two different ways of re-estimating the VAR model are proposed; one in which all parameters are estimated recursively based upon the likelihood function for the first observations......, and another in which the cointegrating relations are estimated recursively from a likelihood function, where the short-run parameters have been concentrated out. We suggest graphical procedures based on recursively estimated eigenvalues to evaluate the constancy of the long-run parameters in the model...

  4. Enhanced extracellular production of L-asparaginase from Bacillus subtilis 168 by B. subtilis WB600 through a combined strategy.

    Science.gov (United States)

    Feng, Yue; Liu, Song; Jiao, Yun; Gao, Hui; Wang, Miao; Du, Guocheng; Chen, Jian

    2017-02-01

    L-asparaginase (EC 3.5.1.1, ASN) exhibits great commercial value due to its uses in the food and medicine industry. In this study, we reported the enhanced expression of type II ASN from Bacillus subtilis 168 in B. subtilis WB600 through a combined strategy. First, eight signal peptides (the signal peptide of the ASN, ywbN, yvgO, amyE, oppA, vpr, lipA, and wapA) were used for ASN secretion in B. subtilis by using Hpa II promoter, respectively. The signal peptide wapA achieved the highest extracellular ASN activity (28.91 U/mL). Second, Hpa II promoter was replaced by a strong promoter, P43 promoter, resulting in 38.1 % enhanced ASN activity. By two rounds of error-prone PCR mutation, the P43 promoter variants with remarkably enhanced strength (D7, E2, H6, B2, and F3) were identified. B2 (-28: A → G, -13: A → G) achieved ASN activity up to 51.13 U/mL. Third, after deletion of the N-terminal 25-residues, ASN activity reached 102.41 U/mL, which was 100 % higher than that of the intact ASN. At last, the extracellular ASN of the B. subtilis arrived at 407.6 U/mL (2.5 g/L of ASN protein) in a 3-L bioreactor by using a fed-batch strategy. The purified ASN showed maximal activity at 65 °C and its half-life at 65 °C was 61 min. The K m and k cat of the ASN were 5.29 mM and 54.4 s -1 , respectively. To the best of our knowledge, we obtained the highest yield of ASN in a food-grade host ever reported, which may benefit the industrial production and application of ASN.

  5. PRODUKSI ANTIBIOTIKA OLEH Bacillus subtilis M10 DALAM MEDIA UREA-SORBITOL

    Directory of Open Access Journals (Sweden)

    Supartono Supartono

    2012-04-01

    Full Text Available PRODUCTION OF ANTIBIOTICS BY Bacillus subtilis M10 IN UREA-SORBITOL MEDIUM. Infection diseases still become the main health problems that suffered by people in Indonesia. Besides, there were many pathogen bacteria found to be resistant to the some antibiotics. Therefore, the efforts to get a new antibiotic require to be done continuously. A new local strain of Bacillus subtilis BAC4 has been known producing an antibiotic that inhibit Serratia marcescens ATCC 27117 growth. To make efficient the local strain, mutation on Bacillus subtilis BAC4 was done by using acridine orange and a mutant cell of Bacillus subtilis M10 that overproduction for producing antibiotic was obtained. Nevertheless, the production kinetics of antibiotic by this mutant has not been reported. The objective of this research was to study the production kinetics of antibiotic by Bacillus subtilis M10 mutant. The production of antibiotic was conducted using batch fermentation and antibiotic assay was performed with agar absorption method using Serratia marcescens ATCC 27117 as bacteria assay. Research result provided that Bacillus subtilis M10 mutant with overproduction of antibiotic produced an antibiotic since 8th hour’s fermentation and optimum of it production was at 14th hours after inoculation.  Penyakit infeksi masih menjadi masalah yang utama diderita oleh masyarakat Indonesia. Di samping itu, banyak bakteri patogen yang ditemukan resisten terhadap beberapa antibiotika. Oleh karena itu, upaya-upaya untuk mendapatkan antibiotika baru perlu dilakukan secara terus-menerus. Suatu galur lokal baru Bacillus subtilis BAC4 teridentifikasi memproduksi senyawa antibiotika yang menghambat pertumbuhan Serratia marcescens ATCC27117. Untuk memberdayakan galur tersebut, terhadap Bacillus subtilis BAC4 dilakukan mutasi dengan larutan akridin oranye dan diperoleh mutan Bacillus subtilis M10 yang memproduksi antibiotika berlebihan. Namun, kinetika produksi antibiotika oleh Bacillus

  6. The Effect of Tallow As Lipase Inducer on Total of Aspergillus Niger, Lipolitic Activity and Lipase Yield

    Directory of Open Access Journals (Sweden)

    Manik Eirry Sawitri

    2012-02-01

    Full Text Available The objectives of this research was to determined of tallow addition with different concentration as lipase Aspergillus niger inducer to total of A. niger, lipolitic activity and lipase yield. The result showed that tallow addition as inducer in the lipase A. niger production gave no significant effect on total of A. niger (5.3 x 107 – 1.7 x 108 cfu/gram in the medium. Tallow addition gave a highly significant effect on lipolytic activity and yield of lipase A. niger. Lipolytic activity ranged between 32.0354 – 53.1197 U/mg protein, while the yield of lipase was 6.6418–7.8941 µg/ml. The conclusion of this research was the addition of tallow for 8% as the lipase inducer of A. niger on lipase production was  more effective to obtain the optimal result. Keywords : Tallow, lipase, inducer, Aspergillus niger

  7. Anatomy of the bacitracin resistance network in Bacillus subtilis.

    Science.gov (United States)

    Radeck, Jara; Gebhard, Susanne; Orchard, Peter Shevlin; Kirchner, Marion; Bauer, Stephanie; Mascher, Thorsten; Fritz, Georg

    2016-05-01

    Protection against antimicrobial peptides (AMPs) often involves the parallel production of multiple, well-characterized resistance determinants. So far, little is known about how these resistance modules interact and how they jointly protect the cell. Here, we studied the interdependence between different layers of the envelope stress response of Bacillus subtilis when challenged with the lipid II cycle-inhibiting AMP bacitracin. The underlying regulatory network orchestrates the production of the ABC transporter BceAB, the UPP phosphatase BcrC and the phage-shock proteins LiaIH. Our systems-level analysis reveals a clear hierarchy, allowing us to discriminate between primary (BceAB) and secondary (BcrC and LiaIH) layers of bacitracin resistance. Deleting the primary layer provokes an enhanced induction of the secondary layer to partially compensate for this loss. This study reveals a direct role of LiaIH in bacitracin resistance, provides novel insights into the feedback regulation of the Lia system, and demonstrates a pivotal role of BcrC in maintaining cell wall homeostasis. The compensatory regulation within the bacitracin network can also explain how gene expression noise propagates between resistance layers. We suggest that this active redundancy in the bacitracin resistance network of B. subtilis is a general principle to be found in many bacterial antibiotic resistance networks. © 2016 John Wiley & Sons Ltd.

  8. Fitness Trade-Offs in Competence Differentiation of Bacillus subtilis.

    Science.gov (United States)

    Yüksel, Melih; Power, Jeffrey J; Ribbe, Jan; Volkmann, Thorsten; Maier, Berenike

    2016-01-01

    In the stationary phase, Bacillus subtilis differentiates stochastically and transiently into the state of competence for transformation (K-state). The latter is associated with growth arrest, and it is unclear how the ability to develop competence is stably maintained, despite its cost. To quantify the effect differentiation has on the competitive fitness of B. subtilis, we characterized the competition dynamics between strains with different probabilities of entering the K-state. The relative fitness decreased with increasing differentiation probability both during the stationary phase and during outgrowth. When exposed to antibiotics inhibiting cell wall synthesis, transcription, and translation, cells that differentiated into the K-state showed a selective advantage compared to differentiation-deficient bacteria; this benefit did not require transformation. Although beneficial, the K-state was not induced by sub-MIC concentrations of antibiotics. Increasing the differentiation probability beyond the wt level did not significantly affect the competition dynamics with transient antibiotic exposure. We conclude that the competition dynamics are very sensitive to the fraction of competent cells under benign conditions but less sensitive during antibiotic exposure, supporting the picture of stochastic differentiation as a fitness trade-off.

  9. A Combinatorial Kin Discrimination System in Bacillus subtilis.

    Science.gov (United States)

    Lyons, Nicholas A; Kraigher, Barbara; Stefanic, Polonca; Mandic-Mulec, Ines; Kolter, Roberto

    2016-03-21

    Multicellularity inherently involves a number of cooperative behaviors that are potentially susceptible to exploitation but can be protected by mechanisms such as kin discrimination. Discrimination of kin from non-kin has been observed in swarms of the bacterium Bacillus subtilis, but the underlying molecular mechanism has been unknown. We used genetic, transcriptomic, and bioinformatic analyses to uncover kin recognition factors in this organism. Our results identified many molecules involved in cell-surface modification and antimicrobial production and response. These genes varied significantly in expression level and mutation phenotype among B. subtilis strains, suggesting interstrain variation in the exact kin discrimination mechanism used. Genome analyses revealed a substantial diversity of antimicrobial genes present in unique combinations in different strains, with many likely acquired by horizontal gene transfer. The dynamic combinatorial effect derived from this plethora of kin discrimination genes creates a tight relatedness cutoff for cooperation that has likely led to rapid diversification within the species. Our data suggest that genes likely originally selected for competitive purposes also generate preferential interactions among kin, thus stabilizing multicellular lifestyles. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. A major protein component of the Bacillus subtilis biofilm matrix.

    Science.gov (United States)

    Branda, Steven S; Chu, Frances; Kearns, Daniel B; Losick, Richard; Kolter, Roberto

    2006-02-01

    Microbes construct structurally complex multicellular communities (biofilms) through production of an extracellular matrix. Here we present evidence from scanning electron microscopy showing that a wild strain of the Gram positive bacterium Bacillus subtilis builds such a matrix. Genetic, biochemical and cytological evidence indicates that the matrix is composed predominantly of a protein component, TasA, and an exopolysaccharide component. The absence of TasA or the exopolysaccharide resulted in a residual matrix, while the absence of both components led to complete failure to form complex multicellular communities. Extracellular complementation experiments revealed that a functional matrix can be assembled even when TasA and the exopolysaccharide are produced by different cells, reinforcing the view that the components contribute to matrix formation in an extracellular manner. Having defined the major components of the biofilm matrix and the control of their synthesis by the global regulator SinR, we present a working model for how B. subtilis switches between nomadic and sedentary lifestyles.

  11. DNA repair in ultraviolet-irradiated spores of Bacillus subtilis

    International Nuclear Information System (INIS)

    Wang, T.C.V.

    1976-01-01

    It has been shown previously by others that at least two independent repair mechanisms are present in Bacillus subtilis for removing ''spore photoproduct'' from DNA of ultraviolet (254 nm)-irradiated spores after germination. One of these, designated as ''spore repair,'' is shown in this study to restore ''spore photoproduct'' to two thymine residues, leaving the DNA backbone intact at the end of the process in vivo. The circumstances under which this repair can occur and some characteristics of its energy requirements have been clarified. The second repair process is identified as excision repair, which can excise both ''spore photoproduct'' from DNA of irradiated spores and cyclobutane-type pyrimidine dimers from DNA of irradiated vegetative cells. In this study it is shown that the gene hcr 1 affects an enzyme activity for the incision step initiating this repair, while the gene hcr 42 affects a step subsequent to incision in the mechanism. In addition a third, independent repair system, termed ''germinative excision repair,'' is discovered and shown to be specific for excising only cyclobutane-type pyrimidine dimers but not ''spore photoproduct.'' This repair system is responsible for the observed high ultraviolet-resistance and temporary capacity for host cell reactivation on recently germinated spores of Bacillus subtilis HCR - strains

  12. Analysis of Spo0M function in Bacillus subtilis.

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    Luz Adriana Vega-Cabrera

    Full Text Available Spo0M has been previously reported as a regulator of sporulation in Bacillus subtilis; however, little is known about the mechanisms through which it participates in sporulation, and there is no information to date that relates this protein to other processes in the bacterium. In this work we present evidence from proteomic, protein-protein interaction, morphological, subcellular localization microscopy and bioinformatics studies which indicate that Spo0M function is not necessarily restricted to sporulation, and point towards its involvement in other stages of the vegetative life cycle. In the current study, we provide evidence that Spo0M interacts with cytoskeletal proteins involved in cell division, which suggest a function additional to that previously described in sporulation. Spo0M expression is not restricted to the transition phase or sporulation; rather, its expression begins during the early stages of growth and Spo0M localization in B. subtilis depends on the bacterial life cycle and could be related to an additional proposed function. This is supported by our discovery of homologs in a broad distribution of bacterial genera, even in non-sporulating species. Our work paves the way for re-evaluation of the role of Spo0M in bacterial cell.

  13. DNA Repair and Genome Maintenance in Bacillus subtilis

    Science.gov (United States)

    Lenhart, Justin S.; Schroeder, Jeremy W.; Walsh, Brian W.

    2012-01-01

    Summary: From microbes to multicellular eukaryotic organisms, all cells contain pathways responsible for genome maintenance. DNA replication allows for the faithful duplication of the genome, whereas DNA repair pathways preserve DNA integrity in response to damage originating from endogenous and exogenous sources. The basic pathways important for DNA replication and repair are often conserved throughout biology. In bacteria, high-fidelity repair is balanced with low-fidelity repair and mutagenesis. Such a balance is important for maintaining viability while providing an opportunity for the advantageous selection of mutations when faced with a changing environment. Over the last decade, studies of DNA repair pathways in bacteria have demonstrated considerable differences between Gram-positive and Gram-negative organisms. Here we review and discuss the DNA repair, genome maintenance, and DNA damage checkpoint pathways of the Gram-positive bacterium Bacillus subtilis. We present their molecular mechanisms and compare the functions and regulation of several pathways with known information on other organisms. We also discuss DNA repair during different growth phases and the developmental program of sporulation. In summary, we present a review of the function, regulation, and molecular mechanisms of DNA repair and mutagenesis in Gram-positive bacteria, with a strong emphasis on B. subtilis. PMID:22933559

  14. The ESX system in Bacillus subtilis mediates protein secretion.

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    Laura A Huppert

    Full Text Available Esat-6 protein secretion systems (ESX or Ess are required for the virulence of several human pathogens, most notably Mycobacterium tuberculosis and Staphylococcus aureus. These secretion systems are defined by a conserved FtsK/SpoIIIE family ATPase and one or more WXG100 family secreted substrates. Gene clusters coding for ESX systems have been identified amongst many organisms including the highly tractable model system, Bacillus subtilis. In this study, we demonstrate that the B. subtilis yuk/yue locus codes for a nonessential ESX secretion system. We develop a functional secretion assay to demonstrate that each of the locus gene products is specifically required for secretion of the WXG100 virulence factor homolog, YukE. We then employ an unbiased approach to search for additional secreted substrates. By quantitative profiling of culture supernatants, we find that YukE may be the sole substrate that depends on the FtsK/SpoIIIE family ATPase for secretion. We discuss potential functional implications for secretion of a unique substrate.

  15. Pulsed dielectric barrier discharge for Bacillus subtilis inactivation in water

    Science.gov (United States)

    Hernández-Arias, A. N.; Rodríguez-Méndez, B. G.; López-Callejas, R.; Valencia-Alvarado, R.; Mercado-Cabrera, A.; Peña-Eguiluz, R.; Barocio, S. R.; Muñoz-Castro, A. E.; de la Piedad Beneitez, A.

    2012-06-01

    The inactivation of Bacillus subtilis bacteria in water has been experimentally studied by means of a pulsed dielectric barrier discharge (PDBD) in a coaxial reactor endowed with an alumina dielectric. The plasma source is capable of operating at atmospheric pressure with gas, water or hybrid gas-liquid media at adjustable 25 kV pulses, 30 μs long and at a 500 Hz frequency. In order to evaluate the inactivation efficiency of the system, a set of experiments were designed on the basis of oxygen flow control. The initial data have showed a significant bacterial rate reduction of 103-107 CFU/mL. Additional results proved that applying an oxygen flow for a few seconds during the PDBD treatment inactivates the Bacillus subtilis population with 99.99% effectiveness. As a reference, without gas flow but with the same exposure times, this percentage is reduced to ~90%. The analysis of the relationship between inactivation rate and chemical species in the discharge has been carried out using optical emission spectroscopy as to identifying the main reactive species. Reactive oxygen species such as atomic oxygen and ozone tuned out to be the dominant germicidal species. Some proposed inactivation mechanisms of this technique are discussed.

  16. Evidence for differentiation of cell wall poles in Bacillus subtilis

    International Nuclear Information System (INIS)

    Sonnenfeld, E.M.

    1985-01-01

    Previous data have suggested that the chromosome of Bacillus subtilis was found to the cell surface at polar regions. A significant corollary of DNA attachment to cell poles is the role of the cell wall in chromosome segregation. This project was mainly concerned with visualizing the DNA-cell wall association through autoradiography. The origin and terminus of replication were labelled with ( 3 H)-thymidine using a temperature-sensitive DNA initiation mutant. It was found that most of the radioactivity was associated with cell poles. Ultrastructural analyses of cell walls stained with dilute cationized ferritin showed that the polar area contained a site of dense electronegativity. It is not immediately apparent why cell wall poles would contain an area with a high concentration of negative charge. This finding may be related to the cell pole functioning as the site of chromosome attachment. An additional observation encountered in this study was that cell wall exhibited asymmetry with regard to negative charge, the outside surface being more electronegative than the inside. A significant consequence of this finding is that both teichoic acid and muramyl peptides are situated perpendicularly to the cell surface. This favored arrangement may facilitate cell separation during the division process due to opposition of like charges at septa. The results of this work provide further convincing evidence that the cell wall of B. subtilis is differentiated

  17. Pulsed dielectric barrier discharge for Bacillus subtilis inactivation in water

    International Nuclear Information System (INIS)

    Hernández-Arias, A N; López-Callejas, R; De la Piedad Beneitez, A; Rodríguez-Méndez, B G; Valencia-Alvarado, R; Mercado-Cabrera, A; Peña-Eguiluz, R; Barocio, S R; Muñoz-Castro, A E

    2012-01-01

    The inactivation of Bacillus subtilis bacteria in water has been experimentally studied by means of a pulsed dielectric barrier discharge (PDBD) in a coaxial reactor endowed with an alumina dielectric. The plasma source is capable of operating at atmospheric pressure with gas, water or hybrid gas-liquid media at adjustable 25 kV pulses, 30 μs long and at a 500 Hz frequency. In order to evaluate the inactivation efficiency of the system, a set of experiments were designed on the basis of oxygen flow control. The initial data have showed a significant bacterial rate reduction of 10 3 -10 7 CFU/mL. Additional results proved that applying an oxygen flow for a few seconds during the PDBD treatment inactivates the Bacillus subtilis population with 99.99% effectiveness. As a reference, without gas flow but with the same exposure times, this percentage is reduced to ∼90%. The analysis of the relationship between inactivation rate and chemical species in the discharge has been carried out using optical emission spectroscopy as to identifying the main reactive species. Reactive oxygen species such as atomic oxygen and ozone tuned out to be the dominant germicidal species. Some proposed inactivation mechanisms of this technique are discussed.

  18. EFFECTS OF MONETARY POLICY IN ROMANIA - A VAR APPROACH

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    Iulian Popescu

    2012-10-01

    Full Text Available Understanding how monetary policy decisions affect inflation and other economic variables is particularly important. In this paper we consider the implications of monetary policy under the inflation targeting regime in Romania, based on an autoregressive vector method including recursive VAR and structural VAR (SVAR. Therefore, we focus on assessing the extent and persistence of monetary policy effects on gross domestic product (GDP, price level, extended monetary aggregate (M3 and exchange rate. The main results of VAR analysis reflect a negative response of consumer price index (CPI, GDP and M3 and positive nominal exchange rate behaviour to a monetary policy shock, and also a limited impact of a short-term interest rate shock in explaining the consumer prices, production and exchange rate fluctuations.

  19. Molecular Dynamics Approach in Designing Thermostable Aspergillus niger Xylanase

    Science.gov (United States)

    Malau, N. D.; Sianturi, M.

    2017-03-01

    Molecular dynamics methods we have applied as a tool in designing thermostable Aspergillus niger Xylanase, by examining Root Mean Square Deviation (RMSD) and The Stability of the Secondary Structure of enzymes structure at its optimum temperature and compare with its high temperature behavior. As RMSD represents structural fluctuation at a particular temperature, a better understanding of this factor will suggest approaches to bioengineer these enzymes to enhance their thermostability. In this work molecular dynamic simulations of Aspergillus niger xylanase (ANX) have been carried at 400K (optimum catalytic temperature) for 2.5 ns and 500K (ANX reported inactive temperature) for 2.5 ns. Analysis have shown that the Root Mean Square Deviation (RMSD) significant increase at higher temperatures compared at optimum temperature and some of the secondary structures of ANX that have been damaged at high temperature. Structural analysis revealed that the fluctuations of the α-helix and β-sheet regions are larger at higher temperatures compared to the fluctuations at optimum temperature.

  20. Biosorption of heavy metals by pretreated biomass of aspergillus niger

    International Nuclear Information System (INIS)

    Javaid, A.; Bajwa, R.; Manzoor, T.

    2011-01-01

    The present study reports the bio sorption potential of chemically pretreated mycelial biomass of fungus Aspergillus niger van. Tieghem for Cu(II) and Ni(II) ions from aqueous phase. Fungal biomass was pretreated with different types of alkaline/salts (NaOH, NaHCO/sub 3/, Na/sub 2/CO/sub 3/, NaCl and CaCl/sub 2/), acids (HCl and H/sub 2/SO/sub 4/) and detergent. Pretreatment of biomass with Na/sub 2/CO/sub 3/ and NaOH were proved to increase or maintain adsorption efficiency and capacity in comparison to untreated biomass. Pretreatment with NaHCO/sub 3/, detergent, NaCl and CaCl/sub 2/ significantly reduce (10-40%) metal sequestering efficiency of the adsorbent. Whereas, acid treatments resulted in drastic loss (80%) in metal uptake efficiency of the biomass. Amongst various pretreatments, Na/sub 2/CO/sub 3/ could be use efficiently for the removal of Ni(II) and Cu(II) ions from aqueous solution using A. niger. (author)

  1. Mapping the polysaccharide degradation potential of Aspergillus niger

    Science.gov (United States)

    2012-01-01

    Background The degradation of plant materials by enzymes is an industry of increasing importance. For sustainable production of second generation biofuels and other products of industrial biotechnology, efficient degradation of non-edible plant polysaccharides such as hemicellulose is required. For each type of hemicellulose, a complex mixture of enzymes is required for complete conversion to fermentable monosaccharides. In plant-biomass degrading fungi, these enzymes are regulated and released by complex regulatory structures. In this study, we present a methodology for evaluating the potential of a given fungus for polysaccharide degradation. Results Through the compilation of information from 203 articles, we have systematized knowledge on the structure and degradation of 16 major types of plant polysaccharides to form a graphical overview. As a case example, we have combined this with a list of 188 genes coding for carbohydrate-active enzymes from Aspergillus niger, thus forming an analysis framework, which can be queried. Combination of this information network with gene expression analysis on mono- and polysaccharide substrates has allowed elucidation of concerted gene expression from this organism. One such example is the identification of a full set of extracellular polysaccharide-acting genes for the degradation of oat spelt xylan. Conclusions The mapping of plant polysaccharide structures along with the corresponding enzymatic activities is a powerful framework for expression analysis of carbohydrate-active enzymes. Applying this network-based approach, we provide the first genome-scale characterization of all genes coding for carbohydrate-active enzymes identified in A. niger. PMID:22799883

  2. Balneological Evaluation of the Tafadek Spring, Agadez Region, Niger Republic

    Science.gov (United States)

    Nghargbu, K.; Latour, T.; Ponikowska, I.; Kurowska, E.

    2012-04-01

    West Africa, particularly Niger Republic is home to thousands of tourists annually. The vast Saharan desert and it's numerous oases in the northern parts of the Republic are a hot attraction on their own. However, in a recent survey of medicinal springs within the West African sub-region, the only hot spring in this country known locally for its therapeutic egress was analyzed. Located about 160km West of Agadez, the "Tafadek" spring with a yield of over 5l/s and temperature of about 50oC, rich in fluoride and silica is a specific water with capacity for application in balneotherapy for the treatment of orthopaedic, rheumatological, neurological, urinary tract infections, and osteoporosis. If the Tafadek spring is developed into a modern health resort promoting balneotherapy, health (balnear) tourism which is non-existent in Niger Republic today could kick start a new dawn in the health/economic development of the nation and the sub-region at large. Keywords: West Africa, Nigeria, Balneotherapy, Health tourism, Spring

  3. Triangulation, Emotional Reactivity, and Violence in the Niger Delta

    Directory of Open Access Journals (Sweden)

    Benjamin Aigbe Okonofua

    2013-04-01

    Full Text Available The Niger Delta conflict, for many years, was blamed on myriad forces, including greed, economic exploitation, pollution and ecological damage, resource appropriation and distribution disputes, ethno-religious antagonisms, poverty, unemployment, large-scale infrastructural deficits, corruption, militarization of oil producing communities and election processes, sociopolitical marginalization, cultism, and weapons proliferation. While all of these issues are important, they are not nearly as important as the deliberate roles played by high-level social, economic, and political interests who activated violence as a means to secure economic advantage from the delta’s oil industry. This study shines the light on this small, exclusive, and very powerful group whose actions triggered off the violence and yet are at the center of efforts to institute peace including the current disarmament, demobilization, and reintegration (DDR program. I argue that unless the contributions of these powerful interests are carefully teased out and the structures they have built to advantage themselves from the conflict are dismantled, peace will remain elusive in the Niger Delta.

  4. Structural Style and Lead Identification, Northern Depobelt, Niger Delta, Nigeria

    International Nuclear Information System (INIS)

    Ola, P. S.; Adekoya, J. A.

    2003-01-01

    By interpreting biofacies data, wire line log and grid of 2D seismic sections in an integrated manner in some portions of the northern depobelt, Niger delta, the sequence stratigraphic framework of the area was established. This enabled the structural style and genetic sequences of the area to be inferred. Results showed that the depobelt could be I subdivided into minibasins that trend in a NW SE direction and are bounded by synthetic faults in the proximal end and shale diapers in the distal end. All the exploration wells in the area of study, which were drilled on structural highs and were very close to the synthetic faults, turned out to be dry whereas the synclinal lows that resulted from local deposition of sands of the first genetic sequences in each of the minibasins could contain hydrocarbon. Such areas of synclinal lows are hereby proposed, as lead in this study. The intervals are untested and occur faraway from existing wells. By projection the geochemical data of well Oben-1 in the area suggest that the intervals fall within the oil generative window. Characteristic seismic reflection termination patterns, which are predominantly down laps and on laps suggest existence of structural closure for hydrocarbon accumulation within the synclinal lows. This study therefore recommends a reappraisal of these leads using a more focused 3D seismic study. The northern delta depobelt is less risky and inexpensive for oil exploration and exploitation compared with the offshore Niger delta that is gaining more prominence

  5. Factors Affecting Rural Households’ Resilience to Food Insecurity in Niger

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    Aboubakr Gambo Boukary

    2016-03-01

    Full Text Available Niger faces many natural and human constraints explaining the erratic evolution of its agricultural production over time. Unfortunately, this is likely to cause a decline in the food supply. This study attempts to identify factors affecting rural households’ resilience to food insecurity in Niger. For this, we first create a resilience index by using principal component analysis and later apply structural equation modeling to identify its determinants. Data from the 2010 National Survey on Households’ Vulnerability to Food Insecurity done by the National Institute of Statistics is used. The study shows that asset and social safety net indicators are significant and have a positive impact on households’ resilience. Climate change approximated by long-term mean rainfall has a negative and significant effect on households’ resilience. Therefore, to strengthen households’ resilience to food insecurity, there is a need to increase assistance to households through social safety nets and to help them gather more resources in order to acquire more assets. Furthermore, early warning of climatic events could alert households, especially farmers, to be prepared and avoid important losses that they experience anytime an uneven climatic event occurs.

  6. Removing the regional level from the Niger vaccine supply chain.

    Science.gov (United States)

    Assi, Tina-Marie; Brown, Shawn T; Kone, Souleymane; Norman, Bryan A; Djibo, Ali; Connor, Diana L; Wateska, Angela R; Rajgopal, Jayant; Slayton, Rachel B; Lee, Bruce Y

    2013-06-10

    Since many of the world's vaccine supply chains contain multiple levels, the question remains of whether removing a level could bring efficiencies. We utilized HERMES to generate a detailed discrete-event simulation model of Niger's vaccine supply chain and compared the current four-tier (central, regional, district, and integrated health center levels) with a modified three-tier structure (removing the regional level). Different scenarios explored various accompanying shipping policies and frequencies. Removing the regional level and implementing a collection-based shipping policy from the district stores increases vaccine availability from a mean of 70-100% when districts could collect vaccines at least weekly. Alternatively, implementing a delivery-based shipping policy from the central store monthly in three-route and eight-route scenarios only increases vaccine availability to 87%. Restricting central-to district vaccine shipments to a quarterly schedule for three-route and eight-route scenarios reduces vaccine availability to 49%. The collection-based shipping policy from district stores reduces supply chain logistics cost per dose administered from US$0.14 at baseline to US$0.13 after removing the regional level. Removing the regional level from Niger's vaccine supply chain can substantially improve vaccine availability as long as certain concomitant adjustments to shipping policies and frequencies are implemented. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Thermal Models of the Niger Delta: Implications for Charge Modelling

    International Nuclear Information System (INIS)

    Ejedawe, J.

    2002-01-01

    There are generally three main sources of temperature data-BHT data from log headers, production temperature data, and continuo's temperature logs. Analysis of continuous temperature profiles of over 100 wells in the Niger Delta two main thermal models (single leg and dogleg) are defined with occasional occurrence of a modified dogleg model.The dogleg model is characterised by a shallow interval of low geothermal gradient ( 3.0.C/100m). This is characteristically developed onshore area is simple, requiring only consideration of heat transients, modelling in the onshore require modelling programmes with built in modules to handle convective heat flow dissipation in the shallow layer. Current work around methods would involve tweaking of thermal conductivity values to mimic the underlying heat flow process effects, or heat flow mapping above and below the depth of gradient change. These methods allow for more realistic thermal modelling, hydrocarbon type prediction, and also more accurate prediction of temperature prior to drilling and for reservoir rock properties. The regional distribution of the models also impact on regional hydrocarbon distribution pattern in the Niger Delta

  8. Activities of Protection against Ionizing Radiation in Niger

    International Nuclear Information System (INIS)

    Kando Hamadou, M.

    2008-01-01

    Niger, sahelian country of Western Africa, is limited to North by Libya and Algeria, to the South by Nigeria and the Benin, to the East by Chad and the West by Mali and Burkina Faso. It covers a surface of 1 267 000 km2 and has a population of approximately 12 000 000 inhabitants. Niger is a large uranium producer with two extraction and treatment development companies of uranium ore which are the company of the mines of Air (SOMAIR) created in 1971 and the mining company of Akouta (COMINAK) created in 1978. Beyond the mining sector, ionizing radiation sources are used in the fields of industry, health, teaching and research. The first lawful text of protection against ionizing radiation was signed on December 5, 1979 and specifically related to the mining activities of uranium. With the multiform assistance of International Atomic Energy Agency (IAEA) protection against radiation knew a significant evolution. A national centre of protection against radiation was created in 1998, two laws relating to the field were adopted in June 2006 and three lawful texts of application of these laws are in the process of finalization

  9. To the issue of increasing efficiency of VAR compensation

    Directory of Open Access Journals (Sweden)

    Світлана Костянтинівна Поднебенна

    2015-11-01

    Full Text Available This article describes the features of VAR compensation of variable loads. One of the most common non-symmetric non-linear power consumers are welding power sources. Time and duration of the work of these sources vary randomly. To compensate the consumption of reactive power on the basis of consumption data from the three-phase electricity meters is inefficient. Compensation devices power should be calculated taking into account the asymmetrical consumption/generation of reactive power per phase and changing consumption patterns. Thyristor-controlled reactor, thyristor-switched capacitors, hybrid VAR compensators, active compensators (STATCOMs, «dynamic capacitors» can be used as the VAR compensation devices. Thyristor-controlled reactors can provide smooth regulation of reactive power, but they have high weight and size parameters and are additional sources of higher harmonics. Thyristor-switched capacitors provide stepwise adjustment of reactive power and are subject to the current higher harmonics. Hybrid VAR compensators make it possible to isolate capacitors from the higher harmonics and ensure smooth regulation, which is achieved by active filter introduction to the reactive power compensation devices based on thyristor-switched capacitors. However, this increases the cost of a compensator and complicates its control system. STATCOMs provide smooth regulation of reactive power, but they are too expensive.Perspective direction in the development of effective VAR compensation devices is «dynamic capacitor». As a result of a feasibility study the prospects for further research of electrical grids power efficiency through the development of effective devices for VAR compensation have been established

  10. The Aspergillus niger growth on the treated concrete substrate using variable antifungals

    Science.gov (United States)

    Parjo, U. K.; Sunar, N. M.; Leman, A. M.; Gani, P.; Embong, Z.; Tajudin, S. A. A.

    2016-11-01

    The aim of this study was to evaluate the Aspergillus niger (A. niger) growth on substrates after incorporates with different compounds of antifungals which is normally used in food industry. The antifungals named as potassium sorbate (PS), calcium benzoate (CB) and zinc salicylate (ZS) were applied on concrete substrate covered with different wall finishing such as acrylic paint (AP), glycerol based paint (GBP), thin wallpaper (THIN) and thick wallpaper (THICK). The concrete substrate were inoculated with spore suspension, incubated at selected temperature (30oC) and relative humidity (90%)in plant growth chamber. The observations were done from the Day 3 until Day 27. The results showed that the growth of the A. niger for concrete treated by PS for AP, GBP, THIN, and THICK were 64%, 32%, 11% and 100%, respectively. Meanwhile for CB, the growth of A. niger on AP, GBP, THIN, and THICK were 100%, 12%, 41%, and 13%, respectively. Similarly, treated concrete by ZS revealed that the growth of A. niger on the same substrate cover were 33%, 47%, 40%, and 39%, respectively. The results obtained in this study provide a valuable knowledge on the abilities of antifungals to remediate A. niger that inoculated on the concrete substrate. Consequently, this study proved that the PS covering with THIN more efficiency compares CB and ZS to prevent A. niger growth.

  11. New prediction for the direct CP-violating parameter var-epsilon prime/var-epsilon and the ΔI=1/2 rule

    International Nuclear Information System (INIS)

    Wu, Yue-Liang

    2001-01-01

    The low-energy dynamics of QCD is investigated with special attention paid to the matching between QCD and chiral perturbation theory (ChPT), and also to some useful algebraic chiral operator relations which survive even when we include chiral loop corrections. It then allows us to evaluate the hadronic matrix elements below the energy scale Λ χ ≅1GeV. Based on the new analyses, we present a consistent prediction for both the direct CP-violating parameter var-epsilonprime/var-epsilon and the ΔI=1/2 rule in kaon decays. In the leading 1/N c approximation, the isospin amplitudes A 0 and A 2 are found to agree well with the data, and the direct CP-violating parameter var-epsilonprime/var-epsilon is predicted to be large, which also confirms our earlier conclusion. Its numerical value is var-epsilonprime/var-epsilon=23.6 -7.8 +12.4 x10 -4 (Imλ t /= 1.2x10 -4 ) which is no longer sensitive to the strange quark mass due to the matching conditions. Taking into account a simultaneous consistent analysis on the isospin amplitudes A 0 and A 2 , the ratio var-epsilonprime/var-epsilon is in favor of the values var-epsilonprime/var-epsilon=(20±9)x10 -4

  12. Saccharomyces cerevisiae var. boulardii fungemia following probiotic treatment

    Directory of Open Access Journals (Sweden)

    Marcelo C. Appel-da-Silva

    2017-12-01

    Full Text Available Probiotics are commonly prescribed as an adjuvant in the treatment of antibiotic-associated diarrhea caused by Clostridium difficile. We report the case of an immunocompromised 73-year-old patient on chemotherapy who developed Saccharomyces cerevisiae var. boulardii fungemia in a central venous catheter during treatment of antibiotic-associated pseudomembranous colitis with the probiotic Saccharomyces cerevisiae var. boulardii. Fungemia was resolved after interruption of probiotic administration without the need to replace the central venous line. Keywords: Saccharomyces, Probiotics, Fungemia, Critical illness, Clostridium difficile

  13. Inhibition of quorum sensing-mediated virulence in Serratia marcescens by Bacillus subtilis R-18.

    Science.gov (United States)

    Devi, Kannan Rama; Srinivasan, Subramaniyan; Ravi, Arumugam Veera

    2018-04-13

    Serratia marcescens is an opportunistic human pathogen causing various nosocomial infections, most importantly urinary tract infections (UTIs). It exhibits increased resistance towards the conventional antibiotics. This study was aimed to evaluate the anti-virulence effect of a rhizosphere soil bacterium Bacillus subtilis strain R-18 against the uropathogen S. marcescens. First, the bacterial cell-free culture supernatant (CFCS) of B. subtilis strain R-18 was evaluated for its quorum sensing inhibitory (QSI) potential against biomarker strain Chromobacterium violaceum and the test pathogen S. marcescens. The B. subtilis R-18 CFCS effectively inhibited the quorum sensing (QS)-mediated violacein pigment production in C. violaceum and prodigiosin pigment production in S. marcescens. Furthermore, B. subtilis R-18 CFCS was successively extracted with different solvent systems. Of these solvents, B. subtilis R-18 petroleum ether (PE) extract showed inhibition in biofilm formation, protease, lipase, and hemolysin productions in S. marcescens. Fourier transform infrared spectroscopic (FT-IR) analysis revealed the alterations in the cellular components of bacterial cell pellets obtained from B. subtilis R-18 PE extract treated and untreated S. marcescens. The differential gene expression study further validated the downregulation of virulence-associated genes. Characterization of the active principle in B. subtilis R-18 PE extract by gas chromatography-mass spectrometry (GC-MS) analysis showed the presence of multiple compounds with therapeutic values, which could possibly reduce the QS-dependent phenotypes in S. marcescens. Copyright © 2018. Published by Elsevier Ltd.

  14. Novel Route for Agmatine Catabolism in Aspergillus niger Involves 4-Guanidinobutyrase.

    Science.gov (United States)

    Kumar, Sunil; Saragadam, Tejaswani; Punekar, Narayan S

    2015-08-15

    Agmatine, a significant polyamine in bacteria and plants, mostly arises from the decarboxylation of arginine. The functional importance of agmatine in fungi is poorly understood. The metabolism of agmatine and related guanidinium group-containing compounds in Aspergillus niger was explored through growth, metabolite, and enzyme studies. The fungus was able to metabolize and grow on l-arginine, agmatine, or 4-guanidinobutyrate as the sole nitrogen source. Whereas arginase defined the only route for arginine catabolism, biochemical and bioinformatics approaches suggested the absence of arginine decarboxylase in A. niger. Efficient utilization by the parent strain and also by its arginase knockout implied an arginase-independent catabolic route for agmatine. Urea and 4-guanidinobutyrate were detected in the spent medium during growth on agmatine. The agmatine-grown A. niger mycelia contained significant levels of amine oxidase, 4-guanidinobutyraldehyde dehydrogenase, 4-guanidinobutyrase (GBase), and succinic semialdehyde dehydrogenase, but no agmatinase activity was detected. Taken together, the results support a novel route for agmatine utilization in A. niger. The catabolism of agmatine by way of 4-guanidinobutyrate to 4-aminobutyrate into the Krebs cycle is the first report of such a pathway in any organism. A. niger GBase peptide fragments were identified by tandem mass spectrometry analysis. The corresponding open reading frame from the A. niger NCIM 565 genome was located and cloned. Subsequent expression of GBase in both Escherichia coli and A. niger along with its disruption in A. niger functionally defined the GBase locus (gbu) in the A. niger genome. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  15. The Vibrio cholerae var regulon encodes a metallo-β-lactamase and an antibiotic efflux pump, which are regulated by VarR, a LysR-type transcription factor.

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    Hong-Ting Victor Lin

    Full Text Available The genome sequence of V. cholerae O1 Biovar Eltor strain N16961 has revealed a putative antibiotic resistance (var regulon that is predicted to encode a transcriptional activator (VarR, which is divergently transcribed relative to the putative resistance genes for both a metallo-β-lactamase (VarG and an antibiotic efflux-pump (VarABCDEF. We sought to test whether these genes could confer antibiotic resistance and are organised as a regulon under the control of VarR. VarG was overexpressed and purified and shown to have β-lactamase activity against penicillins, cephalosporins and carbapenems, having the highest activity against meropenem. The expression of VarABCDEF in the Escherichia coli (ΔacrAB strain KAM3 conferred resistance to a range of drugs, but most significant resistance was to the macrolide spiramycin. A gel-shift analysis was used to determine if VarR bound to the promoter regions of the resistance genes. Consistent with the regulation of these resistance genes, VarR binds to three distinct intergenic regions, varRG, varGA and varBC located upstream and adjacent to varG, varA and varC, respectively. VarR can act as a repressor at the varRG promoter region; whilst this repression was relieved upon addition of β-lactams, these did not dissociate the VarR/varRG-DNA complex, indicating that the de-repression of varR by β-lactams is indirect. Considering that the genomic arrangement of VarR-VarG is strikingly similar to that of AmpR-AmpC system, it is possible that V. cholerae has evolved a system for resistance to the newer β-lactams that would prove more beneficial to the bacterium in light of current selective pressures.

  16. 21 CFR 173.145 - Alpha-Galactosidase derived from Mortierella vinaceae var. raffinoseutilizer.

    Science.gov (United States)

    2010-04-01

    ... vinaceae var. raffinoseutilizer. 173.145 Section 173.145 Food and Drugs FOOD AND DRUG ADMINISTRATION... Alpha-Galactosidase derived from Mortierella vinaceae var. raffinoseutilizer. The food additive alpha-galactosidase and parent mycelial microorganism Mortierella vinaceae var. raffinoseutilizer may be safely used...

  17. Cost-effective medium for the production of mosquito pupicidal lipopeptide from Bacillus subtilis subsp. subtilis (VCRC B471).

    Science.gov (United States)

    Bhuvaneswari, S; Manonmani, A M; Geetha, I

    2015-03-01

    A cyclic lipopeptide (CLP), surfactin produced by a strain of Bacillus subtilis subsp. subtilis (VCRC B471) was found to exhibit mosquitocidal activity. The present study was carried out to enhance the surfactin level using low cost material in the production medium. Two carbon sources, glucose and common sugar, and two nitrogen sources, ammonium nitrate and soya were used in the study. Different concentrations of 'C' and 'N' sources were used in the production medium to enhance the production of surfactin. A new medium (SS7) containing 2% sugar, 6% soya and 0.5% common salt with micronutrients was designed which was found to enhance the production of surfactin. The crude mosquitocidal metabolite (CMM) produced in this medium was 3 g/l which was two times higher than that obtained using synthetic medium NYSM. The LC50 dosage of the CMM to the pupal stages of An. stephensi (2.3 μg/ml) was comparable to that obtained with CMM from the conventional medium. The newly designed cost-effective medium designated as sugar soya medium (SSM) enhanced the production of surfactin and the cost of production was estimated as [symbol: see text] 6 per litre, which is six times lesser than that of the conventional medium. Replacement of sodium chloride with cooking salt further reduced the cost of the medium.

  18. High-level expression and characterization of the Bacillus subtilis subsp. subtilis str. BSP1 YwaD aminopeptidase in Pichia pastoris.

    Science.gov (United States)

    Tang, Wei; Li, Zhezhe; Li, Chunhua; Yu, Xianhong; Wang, Fei; Wan, Xin; Wang, Yaping; Ma, Lixin

    2016-06-01

    Aminopeptidases are widely used for creating protein hydrolysates and peptide sequencing. The ywaD gene from a new Bacillus isolate, named Bacillus subtilis subsp. subtilis str. BSP1, was cloned into the yeast expression vector pHBM905A and expressed and secreted by Pichia pastoris strain GS115. The deduced amino acid sequence of the aminopeptidase encoded by the ywaD gene shared up to 98% identity with aminopeptidases from B. subtilis strains 168 and zj016. The yield (3.81 g/l) and specific activity (788 U/mg) of recombinant YwaD in high-density fermentation were extremely high. And 829.83 mg of the purified enzyme (4089.72 U/mg) were harvested. YwaD was glycosylated, and its activity decreased after deglycosylation, which was similar to that of the aminopeptidase from B. subtilis strain zj016. YwaD was most active toward l-arginine-4-nitroanilide. Moreover, it exhibited high resistance to carbamide, which was not true for aminopeptidases from B. subtilis strains 168 and zj016, which could simplify the purification of YwaD. Moreover, the expression and parts of characterization of the aminopeptidase from B. subtilis strain 168 in Pichia pastoris were added as supplementary material. The sequence and other characteristics of YwaD were compared with those of aminopeptidases from B. subtilis strains 168 and zj016, and they will provide a solid foundation for further research on the influence of amino acid mutations on the function of aminopeptidases. Copyright © 2016 Elsevier Inc. All rights reserved.

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

    DEFF Research Database (Denmark)

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

    2011-01-01

    A characteristic hallmark of Aspergillus niger is the formation of black conidiospores. We have identified four loci involved in spore pigmentation of A. niger by using a combined genomic and classical complementation approach. First, we characterized a newly isolated color mutant, colA, which......-γ-pyrone subclass of polyketides were specifically dependent on fwnA, and funalenone on fwnA, olvA and brnA. Thus, secondary metabolite profiling of the color mutants revealed a close relationship between polyketide synthesis and conidial pigmentation in A. niger....

  20. Heterologous expression of trametes versicolor laccase in pichia pastoris and aspergillus niger

    CSIR Research Space (South Africa)

    Bohlin, C

    2006-09-01

    Full Text Available primarily for screening purposes. With A. niger, high levels of laccase (2700 U/L) were produced using a min- imal medium containing sucrose and yeast extract. Recombinant laccase from A. niger harboring the lcc2 cDNA was purified to homogeneity...). Methods Microbial Strains and Recombinant DNA The lcc1 and lcc2 cDNA genes from T. (Coriolus, Polyporus) versicolor (9–11) were used in the construction of plasmids for expression of laccases in P. pastoris and A. niger. For the expression in P...

  1. Electron spin resonance (ESR) studies on irradiated cocoa beans and niger seeds

    International Nuclear Information System (INIS)

    Mangaonkar, S.R.; Natarajan, V.; Sastry, M.D.; Desai, S.R.P.; Kulkarni, P.R.

    1997-01-01

    Electron spin resonance (ESR) spectra of irradiated (10kGy) and unirradiated cocoa beans and niger seeds have been compared. Unirradiated cocoa beans failed to give any ESR signal, whereas after irradiation (10kGy) an ESR signal at g = 2.0042 was observed. However, ESR signals are given by both irradiated and unirradiated niger seeds. The intensity of signal was found to be dose-dependent up to 10kGy for both seeds. The signals were stable up to 180 days in both cases. The results indicate the possibility of using ESR for distinguishing between irradiated and unirradiated cocoa beans but not for niger seeds

  2. Morphological and genetic differences between Coptis japonica var. anemonifolia H. Ohba and Coptis japonica var. major Satake in Hokuriku area.

    Science.gov (United States)

    Kitamura, Masashi; Ando, Hirokazu; Sasaki, Yohei

    2018-03-01

    Coptis japonica is widely distributed in Japan, and its dried rhizome is a source of the domestic herbal medicine Coptidis Rhizoma ( Oren). There are three varieties of C. japonica, two of which, namely, C. japonica var. anemonifolia and C. japonica var. major, are important as sources of traditional medicines. Coptis japonica var. anemonifolia and C. japonica var. major are distinguishable on the basis of their ternate or biternate compound leaves, respectively. In the Hokuriku area, where both C. japonica var. anemonifolia and C. japonica var. major grow naturally, some individual plants cannot be identified unambiguously on the basis of leaf morphology because changes in leaf morphology may occur due to intra-variety variation or crossbreeding between the two varieties. In addition, genetic differences between the two varieties have remained unclear. In this study, we employed new genetic and morphological classification approaches to discriminate between the two varieties. Based on the single nucleotide polymorphisms of the tetrahydroberberine oxidase gene, we found four conserved SNPs between the two varieties and were able to classify C. japonica into two varieties and crossbreeds. Furthermore, we introduced a new leaf type index based on the overall degree of leaflet dissection calculated by surface area of a leaflet and length of leaflet margin and petiolule. Using our new index we were able to discriminate between the two varieties and their crossbreeds more accurately than is possible with the conventional discrimination method. Our genetic and morphological classification methods may be used as novel benchmarks to discriminate between the two varieties and their crossbreeds.

  3. High Pressure Germination of Bacillus subtilis Spores with Alterations in Levels and Types of Germination Proteins

    Science.gov (United States)

    2014-01-01

    1ITLE AND SUBTITLE 5a CONTRACTNUMBER High pressure germination of Bacillus subtilis spores with W911NF-09-l-0286 alterations in levels and types of...A moderate high pressure (mHP) of 150 megaPascals (MPa) triggers germination of Bacillus subtilis spores via germinant receptors (GRs), while...germination by a very high pressure (vHP) of550 MPa is GR-independent. The mHP and vHP germination of Bacillus subtilis spores with different levels ofGRs

  4. The Bacillus subtilis Acyl Lipid Desaturase Is a Δ5 Desaturase

    Science.gov (United States)

    Altabe, Silvia G.; Aguilar, Pablo; Caballero, Gerardo M.; de Mendoza, Diego

    2003-01-01

    Bacillus subtilis was recently reported to synthesize unsaturated fatty acids (UFAs) with a double bond at positions Δ5, Δ7, and Δ9 (M. H. Weber, W. Klein, L. Muller, U. M. Niess, and M. A. Marahiel, Mol. Microbiol. 39:1321-1329, 2001). Since this finding would have considerable importance in the double-bond positional specificity displayed by the B. subtilis acyl lipid desaturase, we have attempted to confirm this observation. We report that the double bond of UFAs synthesized by B. subtilis is located exclusively at the Δ5 position, regardless of the growth temperature and the length chain of the fatty acids. PMID:12730185

  5. Bacillus subtilis generates a major specific deletion in pAM beta 1.

    OpenAIRE

    van der Lelie, D; Venema, G

    1987-01-01

    pAM beta 1, a 26.5-kilobase plasmid originally isolated from Streptococcus faecalis, was conjugally transferred from Streptococcus lactis to Bacillus subtilis. No conjugal transfer of pAM beta 1 from B. subtilis to S. lactis was observed. In addition, pAM beta 1 which had been reintroduced in S. lactis after cycling through B. subtilis had lost its conjugal transferability to Streptococcus cremoris, although under the same conditions noncycled pAM beta 1 was transferred at high efficiency. Re...

  6. Adaptation of Bacillus subtilis to Life at Extreme Potassium Limitation.

    Science.gov (United States)

    Gundlach, Jan; Herzberg, Christina; Hertel, Dietrich; Thürmer, Andrea; Daniel, Rolf; Link, Hannes; Stülke, Jörg

    2017-07-05

    Potassium is the most abundant metal ion in every living cell. This ion is essential due to its requirement for the activity of the ribosome and many enzymes but also because of its role in buffering the negative charge of nucleic acids. As the external concentrations of potassium are usually low, efficient uptake and intracellular enrichment of the ion is necessary. The Gram-positive bacterium Bacillus subtilis possesses three transporters for potassium, KtrAB, KtrCD, and the recently discovered KimA. In the absence of the high-affinity transporters KtrAB and KimA, the bacteria were unable to grow at low potassium concentrations. However, we observed the appearance of suppressor mutants that were able to overcome the potassium limitation. All these suppressor mutations affected amino acid metabolism, particularly arginine biosynthesis. In the mutants, the intracellular levels of ornithine, citrulline, and arginine were strongly increased, suggesting that these amino acids can partially substitute for potassium. This was confirmed by the observation that the supplementation with positively charged amino acids allows growth of B. subtilis even at the extreme potassium limitation that the bacteria experience if no potassium is added to the medium. In addition, a second class of suppressor mutations allowed growth at extreme potassium limitation. These mutations result in increased expression of KtrAB, the potassium transporter with the highest affinity and therefore allow the acquisition and accumulation of the smallest amounts of potassium ions from the environment. IMPORTANCE Potassium is essential for every living cell as it is required for the activity for many enzymes and for maintaining the intracellular pH by buffering the negative charge of the nucleic acids. We have studied the adaptation of the soil bacterium Bacillus subtilis to life at low potassium concentrations. If the major high-affinity transporters are missing, the bacteria are unable to grow

  7. The political economy of oil and the Niger Delta crisis

    Science.gov (United States)

    Ighodaro, Osaro O.

    This study is about the burgeoning crisis in Nigeria's Oil Producing Niger Delta region. Discerning the intersecting contributive factors to the crisis, this dissertation suggests that the Niger Delta crisis is symptomatic of challenges to development in Nigeria. Due to the insidious colonial/neo-colonial practices of subjugation, and exploitation of the host communities, it is suggested that the extractive, super-profit motive of Shell, the concomitant environmental degradation, corruption of a bellicose state, ethnic conflict and suffering of the masses are outcomes of a long historically debilitating relationship with international capital which causes irreparable retardation to the host communities. From cash crop economy to a mono-oil economy resources are removed from the communities and used to enhance the colonial state and their post-colonial harbingers of misery. Hence, the indigenous people claim that the Niger Delta is in a crisis, and they are willing to confront the triple alliance of multinational oil companies like Shell, the Nigerian State and the local elite so long as these allies of subjugation continue to neglect the goose that lays the proverbial golden egg (oil that is). Theoretically, a hybrid Political Economy approach was adopted as the over-aching framework for the study, while Dependency theory, modified by what I have called African Transformative scholarly perspective, served as the conceptual tool. Primary and secondary sources of data, including personal observation, interviews, official government documents and other publications were utilized for this analysis. In view of recommendations, it is suggested that first, the Nigerian state should assume decisive and unflinching leadership in holding oil companies responsible for their activities in the host communities; second, oil companies (like Shell) should see themselves as an integral part of the host communities; invest in their development by providing employment opportunities

  8. Micropropagation of Caralluma stalagmifera var. longipetala : A rare ...

    African Journals Online (AJOL)

    An efficient in vitro protocol has been developed for the multiplication of shoots and conservation of a rare succulent medicinal plant Caralluma stalagmifera var. longipetala growing wildly in Karnataka State. Proliferation of multiple shoots was achieved on Murashige and Skoog's (MS) medium supplemented with various ...

  9. Chemical composition of essential oil of Psidium cattleianum var ...

    African Journals Online (AJOL)

    The aim of this study was to investigate the essential oil composition of Psidium cattleianum var. lucidum from South Africa. The essential oils were extracted by hydrodistillation and the components were identified by gas chromatography coupled to mass spectrometry (GC-MS) to determine the chemical composition of the ...

  10. Testing for Granger causality in large mixed-frequency VARs

    NARCIS (Netherlands)

    Götz, T.B.; Hecq, A.W.

    2014-01-01

    In this paper we analyze Granger causality testing in a mixed-frequency VAR, originally proposed by Ghysels (2012), where the difference in sampling frequencies of the variables is large. In particular, we investigate whether past information on a low-frequency variable help in forecasting a

  11. Impacts of Bacillus thuringiensis var. israelensis and Bacillus ...

    African Journals Online (AJOL)

    The study assessed the impact of bio-larvicides- Bacillus thuringiensis var. israelensis (Bti) and B. sphaericus (Bs) on anopheline mosquito larval densities in four selected areas of Lusaka urban district. Larval densities were determined using a standard WHO protocol at each study area prior to and after larviciding.

  12. The identity of zostera marina var. angustifolia Hornemann (Potamogetonaceae)

    NARCIS (Netherlands)

    Hartog, den C.

    1972-01-01

    Since Hornemann (Fl. Dan. 9, 1816, p. 3, pl. 1501) published the name Zostera marina var. angustifolia together with a very poor drawing and the extremely short diagnosis ‘foliis subenerviis’ several interpretations of the identity of this taxon have been given. Some authors regarded it as a

  13. A Bootstrap Cointegration Rank Test for Panels of VAR Models

    DEFF Research Database (Denmark)

    Callot, Laurent

    functions of the individual Cointegrated VARs (CVAR) models. A bootstrap based procedure is used to compute empirical distributions of the trace test statistics for these individual models. From these empirical distributions two panel trace test statistics are constructed. The satisfying small sample...

  14. Local cabbage ( Brassica oleracea var. capitata L.) populations from ...

    African Journals Online (AJOL)

    In previous experiments, we were able to augment cabbages (Brassica oleracea L. var. capitata L.) with two new local open pollinated (OP) populations and one cultivar. The type of use indicated that these are cabbages with thinner and juicier leaves, which predisposes their heads for fine grating and also makes their ...

  15. Fiscal developments and financial stress: a threshold VAR analysis

    Czech Academy of Sciences Publication Activity Database

    Afonso, A.; Baxa, Jaromír; Slavík, M.

    2011-01-01

    Roč. 2011, č. 1319 (2011), s. 1-60 ISSN 1725-2806 Institutional research plan: CEZ:AV0Z10750506 Keywords : fiscal policy * financial markets * threshold VAR Subject RIV: AH - Economics http://library.utia.cas.cz/separaty/2011/E/baxa-0364091.pdf

  16. Anogeissus sericea var. nummalaria King ex Duthie (Combretaceae ...

    Indian Academy of Sciences (India)

    Anogeissus sericea var. nummalaria King ex Duthie (Combretaceae) is moderate sized multipurpose hard wood tree of dry deciduous forests with drooping branches and yellow to brownish-yellow flowers. it is endemic to Rajasthan and is considered to be a threatened tree of the region due to over exploitation for timber ...

  17. Fast Responding Voltage Regulator and Dynamic VAR Compensator

    Energy Technology Data Exchange (ETDEWEB)

    Divan, Deepak [Varentec, Incorporated, San Jose, CA (United States); Moghe, Rohit [Varentec, Incorporated, San Jose, CA (United States); Tholomier, Damien [Varentec, Incorporated, San Jose, CA (United States)

    2014-12-31

    The objectives of this project were to develop a dynamic VAR compensator (DVC) for voltage regulation through VAR support to demonstrate the ability to achieve greater levels of voltage control on electricity distribution networks, and faster response compared to existing grid technology. The goal of the project was to develop a prototype Fast Dynamic VAR Compensator (Fast DVC) hardware device, and this was achieved. In addition to developing the dynamic VAR compensator device, Varentec in partnership with researchers at North Carolina State University (NCSU) successfully met the objectives to model the potential positive impact of such DVCs on representative power networks. This modeling activity validated the ability of distributed dynamic VAR compensators to provide fast voltage regulation and reactive power control required to respond to grid disturbances under high penetration of fluctuating and intermittent distributed energy resources (DERs) through extensive simulation studies. Specifically the following tasks were set to be accomplished: 1) Development of dynamic VAR compensator to support dynamic voltage variations on the grid through VAR control 2) Extensive testing of the DVC in the lab environment 3) Present the operational DVC device to the DOE at Varentec’s lab 4) Formulation of a detailed specification sheet, unit assembly document, test setup document, unit bring-up plan, and test plan 5) Extensive simulations of the DVC in a system with high PV penetration. Understanding the operation with many DVC on a single distribution system 6) Creation and submittal of quarterly and final reports conveying the design documents, unit performance data, modeling simulation charts and diagrams, and summary explanations of the satisfaction of program goals. This report details the various efforts that led to the development of the Fast DVC as well as the modeling & simulation results. The report begins with the introduction in Section II which outlines the

  18. Transcriptional regulation of the Bacillus subtilis menp1 promoter.

    Science.gov (United States)

    Qin, X; Taber, H W

    1996-02-01

    The Bacillus subtilis men genes encode biosynthetic enzymes for formation of the respiratory chain component menaquinone. The menp1 promoter previously was shown to be the primary cis element for menFD gene expression. In the present work, it was found that either supplementation with nonfermentable carbon sources or reutilization of glycolytic end products increased menp1 activity in the late postexponential phase. The effect on menp1 activity by a particular end product (such as acetoin or acetate) was prevented by blocking the corresponding pathway for end product utilization. Alteration of a TGAAA motif within the promoter region resulted in unregulated menp1 activity throughout the culture cycle, irrespective of the carbon source added.

  19. Thinking about Bacillus subtilis as a multicellular organism.

    Science.gov (United States)

    Aguilar, Claudio; Vlamakis, Hera; Losick, Richard; Kolter, Roberto

    2007-12-01

    Initial attempts to use colony morphogenesis as a tool to investigate bacterial multicellularity were limited by the fact that laboratory strains often have lost many of their developmental properties. Recent advances in elucidating the molecular mechanisms underlying colony morphogenesis have been made possible through the use of undomesticated strains. In particular, Bacillus subtilis has proven to be a remarkable model system to study colony morphogenesis because of its well-characterized developmental features. Genetic screens that analyze mutants defective in colony morphology have led to the discovery of an intricate regulatory network that controls the production of an extracellular matrix. This matrix is essential for the development of complex colony architecture characterized by aerial projections that serve as preferential sites for sporulation. While much progress has been made, the challenge for future studies will be to determine the underlying mechanisms that regulate development such that differentiation occurs in a spatially and temporally organized manner.

  20. Amyloid fibers provide structural integrity to Bacillus subtilis biofilms.

    Science.gov (United States)

    Romero, Diego; Aguilar, Claudio; Losick, Richard; Kolter, Roberto

    2010-02-02

    Bacillus subtilis forms biofilms whose constituent cells are held together by an extracellular matrix. Previous studies have shown that the protein TasA and an exopolysaccharide are the main components of the matrix. Given the importance of TasA in biofilm formation, we characterized the physicochemical properties of this protein. We report that purified TasA forms fibers of variable length and 10-15 nm in width. Biochemical analyses, in combination with the use of specific dyes and microscopic analyses, indicate that TasA forms amyloid fibers. Consistent with this hypothesis, TasA fibers required harsh treatments (e.g., formic acid) to be depolymerized. When added to a culture of a tasA mutant, purified TasA restored wild-type biofilm morphology, indicating that the purified protein retained biological activity. We propose that TasA forms amyloid fibers that bind cells together in the biofilm.

  1. Mutagenic effect of tritated water on spores of Bacillus subtilis

    International Nuclear Information System (INIS)

    Tanooka, H.; Munakata, N.

    1978-01-01

    The mutagenic effect of tritiated water was observed with spores of Bacillus subtilis polA strain suspended in 50 mCi/ml of tritiated water for various intervals. Dose rate given by tritium beta particles to spore core was estimated to be 400 rad/hr from some assumptions and E. coli data computed by Bockrath et al. and Sands et al. The initial mutation rate was 4.2 x 10 -9 mutants/rad, as compared with 2.4 x 10 -9 mutants/rad for 60 Co γ rays and 3.3 x 10 -9 mutants/rad for 30-kVp x rays. The mutagenic effect of tritiated water on spores is most likely due to beta particle ionizing radiation damage

  2. Functional requirements of cellular differentiation: lessons from Bacillus subtilis.

    Science.gov (United States)

    Narula, Jatin; Fujita, Masaya; Igoshin, Oleg A

    2016-12-01

    Successful execution of differentiation programs requires cells to assess multitudes of internal and external cues and respond with appropriate gene expression programs. Here, we review how Bacillus subtilis sporulation network deals with these tasks focusing on the lessons generalizable to other systems. With feedforward loops controlling both production and activation of downstream transcriptional regulators, cells achieve ultrasensitive threshold-like responses. The arrangement of sporulation network genes on the chromosome and transcriptional feedback loops allow coordination of sporulation decision with DNA-replication. Furthermore, to assess the starvation conditions without sensing specific metabolites, cells respond to changes in their growth rates with increased activity of sporulation master regulator. These design features of the sporulation network enable cells to robustly decide between vegetative growth and sporulation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Bioproperties of potent nattokinase from Bacillus subtilis YJ1.

    Science.gov (United States)

    Yin, Li-Jung; Lin, Hsin-Hung; Jiang, Shann-Tzong

    2010-05-12

    Fibrinolytic enzyme activity was observed during cultivation of Bacillus subtilis YJ1 in a medium containing 1% skim milk, 1% rice husk, 0.5% NaCl, and 0.25% glucose. It was purified to electrophoretical homogeneity after CM-sepharose FF chromatography. The specific activity and yield were 1791.9 FU/mg and 9.5%, respectively. This purified fibrinolytic enzyme had M of 27.5 kDa, optimal temperature and pH at 50 degrees C and 8.5, respectively. It was stable at pH 6.0-10.0 and 10-40 degrees C and inhibited by Fe(3+), Hg(2+), Cu(2+), Zn(2+), and PMSF. Compared the N terminal of amino acids and full DNA sequence with those in NCBI, it was considered to be a nattokinase.

  4. Proteins that interact with GTP during sporulation of Bacillus subtilis

    International Nuclear Information System (INIS)

    Mitchell, C.; Vary, J.C.

    1989-01-01

    During sporulation of Bacillus subtilis, several proteins were shown to interact with GTP in specific ways. UV light was used to cross-link [α- 32 P]GTP to proteins in cell extracts at different stages of growth. After electrophoresis, 11 bands of radioactivity were found in vegetative cells, 4 more appeared during sporulation, and only 9 remained in mature spores. Based on the labeling pattern with or without UV light to cross-link either [α- 32 P]GTP or [γ- 32 P]GTP, 11 bands of radioactivity were apparent guanine nucleotide-binding proteins, and 5 bands appeared to be phosphorylated and/or guanylated. Similar results were found with Bacillus megaterium. Assuming the GTP might be a type of signal for sporulation, it could interact with and regulate proteins by at least three mechanisms

  5. Use of Aspergillus niger for bioconversion of apple distillery waste

    Energy Technology Data Exchange (ETDEWEB)

    Friedrich, J.; Cimerman, A.; Perdih, A.

    1983-01-01

    The bioconversion of waste material remaining after apple brandy distillation was investigated. Different cellulolytic fungi were tested for their ability to convert the waste organic substances into microbial biomass. An Aspergillus niger strain was chosen as the most convenient microorganism. By growing this mold on the apple slop the following results were obtained: filtration time was shortened by 30 times, reduction of the chemical oxygen demand in the liquid phase in the range of 50-80% depending on the substrate dilution and a dry filter cake enriched with fungal biomass to about 12 g/l containing up to 22% raw proteins and certain amounts of cellulolytic enzymes in the filtrate. The influence of the initial pH, the salt addition and the dilution of the substrate were studied as well. 12 references.

  6. In-silico analysis of Aspergillus niger beta-glucosidases

    Science.gov (United States)

    Yeo S., L.; Shazilah, K.; Suhaila, S.; Abu Bakar F., D.; Murad A. M., A.

    2014-09-01

    Genomic data mining was carried out and revealed a total of seventeen β-glucosidases in filamentous fungi Aspergillus niger. Two of them belonged to glycoside hydrolase family 1 (GH1) while the rest belonged to genes in family 3 (GH3). These proteins were then named according to the nomenclature as proposed by the International Union of Biochemistry (IUB), starting from the lowest pI and glycoside hydrolase family. Their properties were predicted using various bionformatic tools showing the presence of domains for signal peptide and active sites. Interestingly, one particular domain, PA14 (protective antigen) was present in four of the enzymes, predicted to be involved in carbohydrate binding. A phylogenetic tree grouped the two glycoside hydrolase families with GH1 and GH3 related organisms. This study showed that the various domains present in these β-glucosidases are postulated to be crucial for the survival of this fungus, as supported by other analysis.

  7. Biotransformation of (+)-isofraxinellone by Aspergillus niger and insect antifeedant activity.

    Science.gov (United States)

    Okuno, Yoshiharu; Marumoto, Shinsuke; Tsurumi, Jun; Miyazawa, Mitsuo

    2018-01-24

    The biotransformation of (+)-isofraxinellone (1) by Aspergillus niger was investigated. Compound 1 was transformed to only one new compound 2. The structure of 2 was identified as (-)-(4S)-4-hydroxyisofraxinellone which was regio- and stereo-selective hydroxylated at the C-4 position by IR, EI-MS 1D and 2D NMR. Absolute configuration of hydroxyl group at the C-4 position was detected by modified Mosher's method. Antifeedant activity of compounds 1 and 2 against larvae of Spodoptera litura was assayed. These compounds showed potent antifeedant activity and ED 50 (50% of effective dose) values were 3.91 and 4.43 μg/cm 2 , respectively.

  8. New pathway for the biodegradation of indole in Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Kamath, A.; Vaidyanathan, C.S. (Indiana Institute of Science, Bangalore (India))

    1990-01-01

    Indole and its derivatives form a class of toxic recalcitrant environmental pollutants. The growth of Aspergillus niger was inhibited by very low concentrations (0.005 to 0.02%) of indole, even when 125- to 500-fold excess glucose was present in the medium. When 0.02% indole was added, the fungus showed a lag phase for about 30 h and the uptake of glucose was inhibited. Indole was metabolized by a new pathway via indoxyl (3-hydroxyindole), N-formylanthranilic acid, anthranilic acid, 2,3-dihydroxybenzoic acid, and catechol, which was further degraded by an ortho cleavage. The enzymes N-formylanthranilate deformylase, anthranilate hydroxylase, 2,3-dihydroxybenzoate decarboxylase, and catechol dioxygenase were induced by indole as early as after 5 h of growth, and their activities were demonstrated in a cell-free system.

  9. Responses of Aspergillus niger to selected environmental factors

    Directory of Open Access Journals (Sweden)

    Šimonovičová Alexandra

    2017-12-01

    Full Text Available Four wild type strains of A. niger were collected from soil and stream sediments representing environments with variable level of As, Sb, Al, Fe, Cd, Cu, and Zn contamination. Banská Štiavnica-Šobov (S, Pezinok-Kolársky vrch (P and Slovinky (Sl represent contaminated localities. Locality Gabčíkovo (G was as a control site. The influence of toxic elements in these substrates on fungal growth, colony size, enzymatic activity, production of organic acids and their pelletization in water suspensions with montmorillonite was studied. The aim of our study was to find out how the wild type strains from (contaminated environment will behave in different model solutions. We also wanted to add some new information in this area of study, because that there is some gap in the available knowledge.

  10. Acidolysis of coal fly ash by Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Torma, A.E.; Singh, A.K. (EG and G Idaho Inc., Idaho Falls, ID (United States). Center for Biological Processing Technology)

    1993-12-01

    The kinetics of aluminium extraction were investigated, using as-received and calcined fly ash samples and a pure culture of [ital Aspergillus niger]. This fungus metabolized sucrose to citric and oxalic acids, which were involved in the acidolysis of fly ash. Aluminium extraction from as-received fly ash was only 5-8%, whereas from calcined fly ash it was up to 93.5%. The order of reaction and the overall reaction rate constant were determined by the van't Hoff technique with respect to the concentration of calcined fly ash. A linearized form of a modified Monod expression was applied to the experimental data to assess the kinetic constants for the acidolysis process. Statistically designed experiments were carried out with calcined fly ash and synthetic solutions containing citric and oxalic acids to determine the optimum leaching conditions. The acidolysis reaction mechanism is discussed. 28 refs., 6 figs., 3 tabs.

  11. Nanosulfur: A Potent Fungicide Against Food Pathogen, Aspergillus niger

    International Nuclear Information System (INIS)

    Choudhury, Samrat Roy; Goswami, Arunava; Nair, Kishore K.; Kumar, Rajesh; Gopal, Madhuban; Devakumar, C.; Gogoi, Robin; Srivastava, Chitra; Subhramanyam, B. S.

    2010-01-01

    Elemental sulfur (S 0 ), man's oldest eco-friendly fungicide for curing fungal infections in plants and animals, is registered in India as a non-systemic and contact fungicide. However due to its high volume requirement, Indian agrochemical industry and farmers could not effectively use this product till date. We hypothesize that intelligent nanoscience applications might increase the visibility of nanosulfur in Indian agriculture as a potent and eco-safe fungicide. Sulfur nanoparticles (NPs) were synthesized bottom-up via a liquid synthesis method with average particle size in the range of 50-80 nm and the shapes of the NPs were spherical. A comparative study of elemental and nano-sulfur produced has been tested against facultative fungal food pathogen, Aspergillus niger. Results showed that nanosulfur is more efficacious than its elemental form.

  12. Regional trade and border markets between Niger, Benin and Nigeria

    DEFF Research Database (Denmark)

    Walther, Olivier; Tenikué, Michel; Kuepié, Mathias

    The objective of this methodological paper is to identify a number of products or sectors whose trade is relevant for border regions in West Africa. Focusing on Niger, Benin and Nigeria, we start with contextualising the importance of border markets by quantifying the changes in the relative values...... and volumes of imports and exports passing through border posts. In a second step, we determine which are the products most commonly found among the imports and exports of the border posts. The study shows that seven products are recognised as being heavily imported, subject to significant trade from large...... traders, and considered as re-export products: building materials, cereals and flour, textile, used clothing, used vehicles, cigarettes and oil....

  13. Glycan analysis of recombinant Aspergillus niger endo-polygalacturonase A.

    Science.gov (United States)

    Woosley, Bryan D; Kim, Young Hwan; Kumar Kolli, V S; Wells, Lance; King, Dan; Poe, Ryan; Orlando, Ron; Bergmann, Carl

    2006-10-16

    The enzyme endo-polygalacturonase A, or PGA, is produced by the fungus, Aspergillus niger, and appears to play a critical role during invasion of plant cell walls. The enzyme has been homologously overexpressed in order to provide sufficient quantities of purified enzyme for structural and biological studies. We have characterized this enzyme in terms of its post-translational modifications (PTMs) and found it to be both N- and O-glycosylated. Additionally, we have characterized the glycosyl moieties using MALDI-TOF and LC-ESI mass spectrometry. The characterization of all PTMs on PGA, along with molecular modeling, allows us to reveal potential roles played by the glycans in modulating the interaction of the enzyme with other macromolecules.

  14. Catalytical Properties of Free and Immobilized Aspergillus niger Tannase

    Directory of Open Access Journals (Sweden)

    Abril Flores-Maltos

    2011-01-01

    Full Text Available A fungal tannase was produced, recovered, and immobilized by entrapment in calcium alginate beads. Catalytical properties of the immobilized enzyme were compared with those of the free one. Tannase was produced intracellularly by the xerophilic fungus Aspergillus niger GH1 in a submerged fermentation system. Enzyme was recovered by cell disruption and the crude extract was partially purified. The catalytical properties of free and immobilized tannase were evaluated using tannic acid and methyl gallate as substrates. KM and Vmax values for free enzyme were very similar for both substrates. But, after immobilization, KM and Vmax values increased drastically using tannic acid as substrate. These results indicated that immobilized tannase is a better biocatalyst than free enzyme for applications on liquid systems with high tannin content, such as bioremediation of tannery or olive-mill wastewater.

  15. Aggressive keloid-mimicking tumor in Melanosuchus niger in captivity

    Directory of Open Access Journals (Sweden)

    Washington Luiz Assunção Pereira

    2013-07-01

    Full Text Available The objective of this note is to describe a case of exuberant scarring formation, with keloid characteristics and pseudo-tumoral configuration in a male Black caiman (Melanosuchus niger, with an estimated age of 60 years, belonging to the Zoobotanical Park at the Emílio Goeldi Museum, located in Belém, Pará, Brazil. The alteration appeared on the right posterior limb involving two distal phalanges of the lateral digit and measured 12.4cm at the greatest width. The keloid tissue was surgically removed and samples were processed and analyzed histopathologically, revealing growth made up of fibrous connective tissue with the habitual morphology, which was structurally mature in the more central areas.

  16. Nanosulfur: A Potent Fungicide Against Food Pathogen, Aspergillus niger

    Science.gov (United States)

    Choudhury, Samrat Roy; Nair, Kishore K.; Kumar, Rajesh; Gogoi, Robin; Srivastava, Chitra; Gopal, Madhuban; Subhramanyam, B. S.; devakumar, C.; Goswami, Arunava

    2010-10-01

    Elemental sulfur (S0), man's oldest eco-friendly fungicide for curing fungal infections in plants and animals, is registered in India as a non-systemic and contact fungicide. However due to its high volume requirement, Indian agrochemical industry and farmers could not effectively use this product till date. We hypothesize that intelligent nanoscience applications might increase the visibility of nanosulfur in Indian agriculture as a potent and eco-safe fungicide. Sulfur nanoparticles (NPs) were synthesized bottom-up via a liquid synthesis method with average particle size in the range of 50-80 nm and the shapes of the NPs were spherical. A comparative study of elemental and nano-sulfur produced has been tested against facultative fungal food pathogen, Aspergillus niger. Results showed that nanosulfur is more efficacious than its elemental form.

  17. Quantitative Analysis of Neogene Foraminfera in the Central Niger Delta

    International Nuclear Information System (INIS)

    Ojo, A. O.; Salami, M. B.

    2003-01-01

    A ranking and Scaling (RASC) computer programme for zonation and normality testing of paleontological events was employed to identify assemblages of foraminifera species in the sections studied. The emphasis is on ease of zonal recognition and reliability in correlation. A four fold interval zonation of benthonic and some planktonic foraminifera were established. Two distinct temporal and four depositional environments are recognizable. A few benthonic foraminifera appear to have biostratigraphic significance. Bulumina elegans is present in the early Miocene. Cyclammina cancellata, in the middle-late Miocene, while Brizalina beyrichi and Bolivina variabilis are restricted to late Miocene in the studied samples. However, these distributions may be environmentally controlled and therefore may be tell zones. The presence and abundance of neritic fauna with lignitic materials indicate alternating shallow marine and non-marine conditions during deposition in parts of the Niger-delta

  18. Catalytical Properties of Free and Immobilized Aspergillus niger Tannase.

    Science.gov (United States)

    Flores-Maltos, Abril; Rodríguez-Durán, Luis V; Renovato, Jacqueline; Contreras, Juan C; Rodríguez, Raúl; Aguilar, Cristóbal N

    2011-01-01

    A fungal tannase was produced, recovered, and immobilized by entrapment in calcium alginate beads. Catalytical properties of the immobilized enzyme were compared with those of the free one. Tannase was produced intracellularly by the xerophilic fungus Aspergillus niger GH1 in a submerged fermentation system. Enzyme was recovered by cell disruption and the crude extract was partially purified. The catalytical properties of free and immobilized tannase were evaluated using tannic acid and methyl gallate as substrates. K(M) and V(max) values for free enzyme were very similar for both substrates. But, after immobilization, K(M) and V(max) values increased drastically using tannic acid as substrate. These results indicated that immobilized tannase is a better biocatalyst than free enzyme for applications on liquid systems with high tannin content, such as bioremediation of tannery or olive-mill wastewater.

  19. Molecular analysis of Phr peptide processing in Bacillus subtilis.

    Science.gov (United States)

    Stephenson, Sophie; Mueller, Christian; Jiang, Min; Perego, Marta

    2003-08-01

    In Bacillus subtilis, an export-import pathway regulates production of the Phr pentapeptide inhibitors of Rap proteins. Processing of the Phr precursor proteins into the active pentapeptide form is a key event in the initiation of sporulation and competence development. The PhrA (ARNQT) and PhrE (SRNVT) peptides inhibit the RapA and RapE phosphatases, respectively, whose activity is directed toward the Spo0F approximately P intermediate response regulator of the sporulation phosphorelay. The PhrC (ERGMT) peptide inhibits the RapC protein acting on the ComA response regulator for competence with regard to DNA transformation. The structural organization of PhrA, PhrE, and PhrC suggested a role for type I signal peptidases in the processing of the Phr preinhibitor, encoded by the phr genes, into the proinhibitor form. The proinhibitor was then postulated to be cleaved to the active pentapeptide inhibitor by an additional enzyme. In this report, we provide evidence that Phr preinhibitor proteins are subject to only one processing event at the peptide bond on the amino-terminal end of the pentapeptide. This processing event is most likely independent of type I signal peptidase activity. In vivo and in vitro analyses indicate that none of the five signal peptidases of B. subtilis (SipS, SipT, SipU, SipV, and SipW) are indispensable for Phr processing. However, we show that SipV and SipT have a previously undescribed role in sporulation, competence, and cell growth.

  20. The effects of agitation and aeration on the production of gluconic acid by Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Dronawat, S.N.; Svihla, C.K.; Hanley, T.R. [Univ. of Louisville, KY (United States)

    1995-12-31

    The effects of agitation and aeration in the production of gluconic acid by Aspergillus niger from a glucose medium were investigated. Experiments were conducted at aeration rates of 5.0 and 10.0 L/min. Four different agitation speeds were investigated for each aeration rate. Gluconic acid concentration and biomass concentration were analyzed, and the rate of consumption of substrate by A. niger was noted. The main purpose of this work was to find the optimal conditions of agitation and aeration for the growth of A. niger and production of gluconic acid in submerged culture in a batch fermentor at a bench-top scale. The oxygen-transfer rates at different agitation and aeration rates were calculated. The gluconic acid concentration and rate of growth of A. niger increased with increase in the agitation and aeration rates.