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Sample records for rhizopus oryzae mutant

  1. Screening of allyl alcohol resistant mutant of Rhizopus oryzae and ...

    African Journals Online (AJOL)

    Ethanol is a main by-product in the fermentation broth of Rhizopus oryzae during the production of high-optical purity L-lactic acid. By screening the lower activity of alcohol dehydrogenase (ADH) mutant, thus decreasing the flux of pyruvic acid to ethanol may be a virtual method for increasing the conversion rate of glucose ...

  2. Optimization of L(+)-Lactic Acid Fermentation Without Neutralisation of Rhizopus Oryzae Mutant RK02 by Low-Energy Ion Implantation

    International Nuclear Information System (INIS)

    Li Wen; Wang Tao; Yang Yingge; Liu Dan; Fan Yonghong; Wang Dongmei; Yang Qian; Yao Jianming; Zheng Zhiming; Yu Zengliang

    2008-01-01

    In order to get an industrial strain which can yield a high concentration of lactic acid for ISPR (in situ product removal), the original strain Rhizopus oryzae RE3303 was mutated by low-energy ion beam implantation. A mutant RK02 was screened, and the factors such as the substrate concentration, nitrogen source concentration, inoculum size, seed age, aeration and temperature that affect the production of lactic acid were studied in detail. Under optimal conditions, the maximum concentration of L(+)-lactic acid reached 34.85 g/L after 30 h shake-flask cultivation without adding any neutralisation (5% Glucose added), which was a 146% increase in lactic acid production after ion implantation compared with the original strain. It was also shown that RK02 can be used in ISPR to reduce the number of times of separation.

  3. Reduction of hexavalent chromium by Rhizopus Oryzae

    African Journals Online (AJOL)

    EJIRO

    reduction data and the specific growth rate constant value was calculated as 0.082 and the ... Key words: Hexavalent chromium, Rhizopus Oryzae, leather tanning, Monod and Haldane models. ... composition; Glucose 1 g; K2HPO4 0.5 g; NaCl 0.5 g; MgCl2 1.0 g; ... ficantly, because of the inhibitor role of high concentration.

  4. Reduction of hexavalent chromium by Rhizopus Oryzae | Sukumar ...

    African Journals Online (AJOL)

    The ability of Rhizopus oryzae to reduce Cr6+ was evaluated in batch microcosms. The optimum pH of R. oryzae growth was between 6.0 and 7.0. The maximum chromium reduction efficiency of 91.15% and biomass growth was achieved at a pH of 7, temperature of 37°C, with an initial Cr6+ concentration of 400 ppm and ...

  5. Secretory expression of Rhizopus oryzae α-amylase in ...

    African Journals Online (AJOL)

    Kluyveromyces lactis is a non-conventional yeast species extensively used in the expression of heterologous genes. In this study, a genetically modified K. lactis with high-level expression of α- amylase from Rhizopus oryzae was obtained, which could successfully hydrolyze and use starch for growth very well. Shake flask ...

  6. Rhizopus Soft Rot on Lily Caused by Rhizopus oryzae in Korea

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    Soo-Sang Hahm

    2014-03-01

    Full Text Available Rhizopus soft rot of lily (Lilium longiflorum caused by Rhizopus oryzae was observed in the experimental field in Taean Lily Experiment Station in Korea, 2012. The typical symptoms were water-soaked lesions on bottom stem and leaf rot. The lesion rapidly expanded and the plant was softened totally. The fungus grew vigorously at an optimum temperature (25oC and brownish colony and black sporangia were formed on potato dextrose agar medium. Sporangiophores formed on end of sporangia were sub-globose, brownish and 6-10 μm in size. Sporangia were globose, blackish and 87-116 μm in size. Sporangiospores were irregularly oval and sub-globose, brownish 4-8 μm in size. On the basis of mycological characteristics, analyzing sequences of internal transcribed spacer region of ribosomal DNA, and pathogenicity test on host plants, the causal fungus was identified as R. oryzae. This is the first report of Rhizopus soft rot on lily caused by R. oryzae in Korea.

  7. PENGARUH RHIZOPUS ORYZAE DAN ASPERGILLUS ORYZAE TERHADAP KUALITAS KECAP

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    Dewi Sabita Slamet

    2012-11-01

    Full Text Available Telah diteliti pengganti fermentasi mikroorganisme Aspergillus oryzae Rhyzopus oryzae dan campuran Aspergillus dan Rhyzopus oryzae, dengan perendaman dalam larutan garam 20% dalam waktu yang berbeda terhadap kualitas kecap.Lamanya perendaman dalam larutan garam 20% yang berbeda menghasilkan kadar protein kecap yang berbeda. Aspergillus oryzae lebih baik dalam menghasilkan enzima protease dari pada Rhyzopus oryzae.Uji organoleptik menunjukkan perbedaan tidak bermakna dalam hal rasa maupun aroma antar kecap yang dibuat dengan strain jamur yang berlainan serta waktu perendaman yang berbeda. Untuk membuat kecap, sebaiknya dilakukan perendaman dalam larutan garam 20% selama 14 hari.

  8. Pemeraman untuk meningkatkan kualitas keju yang diinnokulasi Rhizopus oryzae

    Directory of Open Access Journals (Sweden)

    SOLIKAH ANA ESTIKOMAH

    2010-11-01

    Full Text Available Estikomah SA, Sutarno, Pangastuti A. 2010. Pemeraman untuk meningkatkaan kualitas keju yang diinokulasi Rhizopus oryzae. Bioteknologi 7: 55-62. Keju merupakan makanan hasil fermentasi dari susu yang proses fermentasinya dilakukan oleh bakteri asam laktat maupun jamur. Rhizopus oryzae diketahui mampu menghasilkan asam laktat, protease, dan lipase. Perubahan cita rasa dan tekstur keju terjadi selama pemeraman keju. Tujuan penelitian ini adalah untuk meningkatkan kualitas keju yang diinokulasi R. oryzae melalui pemeraman. Pemeraman dilakukan dengan variasi waktu (7, 14 hari dan suhu (5ºC, 10ºC, 15ºC. Penelitian ini terdiri dua tahap, yaitu pembuataan keju mentah diikuti pemeraman keju mentah tersebut. Keju penelitian dianalisis nilai pH, kadar lemak, kadar protein, kadar asam amino dan diidentifikasi mikrobanya. Data hasil penellitian dianalisis dengan uji siidik ragam (ANAVA, kemudian dilanjutkan dengan uji berjarak ganda Duncan (DMRT pada taraf signifikansi 5%. Data hasil tingkat kesukaan dianalisis dengan statistik nonparametrik uji Fridman yang dilanjutkaan dengan Wilcoxon Signed Rank Test (WSRT pada taraf sigifikansi 5%. Hasil penelitian menunjukkan bahwa keju peram yang disukai panelis adalah keju peram pada suhu 15ºC selama 14 hari. Kondisi pemeraman berpengaruh terhadap nilai pH, kadar lemak,, kadar proteinn dan tidak berpengaruh pada kadar asam amino. Kualitas keju peram terbaik terdapat pada kondisi suhu 15°C selama 14 hari, memiliki nilai pH 4,40, kadar protein tertinggi yaitu sebesar 99,78%, dan kadar lemak sebesar 35,02%. Hasil identifikasi mikroba pada keju mentah dan keju peram meliputi Enterococcus hirae (Enterococcus faecalis, Bacillus subtilis, dan Aspergillus sp.

  9. Ripening for improving the quality of inoculated cheese Rhizopus oryzae

    Directory of Open Access Journals (Sweden)

    ARTINI PANGASTUTI

    2010-01-01

    Full Text Available Estikomah SA, Sutarno, Pangastuti A 2010. Ripening for improving the quality of inoculated cheese Rhizopus oryzae. Nusantara Bioscience 2: 1-6. Cheese is dairy product resulted from fermented milk in which the fermentation process can be done by lactic acid bacteria or fungus. Rhizopus oryzae is able to produce lactic acid, protease and lipase. The ripening process changes the taste and texture. The purpose of this study is ripening to improve the quality of inoculated cheese R. oryzae. In this research the ripening was conducted the concentration variation of temperature (5oC, 10oC, 15oC, and time (7 days, 14 days. The procedure of research consisted of two steps, namely un-ripened cheese preparation followed by ripening cheese preparation. Cheese produced in this study analyzed the value of pH, fat content, protein content, amino acid levels and identification of microbe with ANOVA then followed by DMRT at 5% level of significance. Data results were analyzed with the like’s nonparametric statistical test, followed by Fridman Wilcoxon Signed Rank Test (WSRT at 5% level significance. The results showed that the preferred ripened cheese panelist was at a temperature of 15oC for 14 days. Ripening conditions affect pH, fat content, protein content and do not affect the levels of amino acids that formed ripened cheese. The best quality ripened cheese i.e. at a temperature of 15°C for 14 days, had a pH value of 4.40, the highest protein content of 9.78%, and fat content of 35.02%. The results of identified microbe in un-ripened cheese and ripened cheese include Enterococcus hirae (Enterococcus faecalis, Bacillus subtilis, and Aspergillus sp.

  10. Metalaxyl Degradation by Mucorales Strains Gongronella sp. and Rhizopus oryzae.

    Science.gov (United States)

    Martins, Maria Rosário; Santos, Cledir; Pereira, Pablo; Cruz-Morais, Júlio; Lima, Nelson

    2017-12-14

    In this study, the degradation of metalaxyl was investigated in the presence of two Mucorales strains, previously isolated from soil subjected to repeated treatments with this fungicide and selected after enrichment technique. Fungal strains were characterised by a polyphasic approach using phylogenetic analysis of the Internal Transcribed Spacer (ITS) gene region, phenotypic characterisation by Matrix-Assisted Laser Desorption Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) spectral analysis, and growth kinetics experiments. The strains were identified as Gongronella sp. and Rhizopus oryzae . The fungal growth kinetics in liquid cultures containing metalaxyl fits with Haldane model. Under laboratory conditions, the ability of Gongronella sp. and R. oryzae cultures to degrade metalaxyl was evaluated in liquid cultures and soil experiments. Both species were able to: (a) use metalaxyl as the main carbon and energy source; and (b) degrade metalaxyl in polluted soils, with rates around 1.0 mg kg - ¹ d - ¹. This suggests these strains could degrade metalaxyl in soils contaminated with this fungicide.

  11. Metalaxyl Degradation by Mucorales Strains Gongronella sp. and Rhizopus oryzae

    Directory of Open Access Journals (Sweden)

    Maria Rosário Martins

    2017-12-01

    Full Text Available In this study, the degradation of metalaxyl was investigated in the presence of two Mucorales strains, previously isolated from soil subjected to repeated treatments with this fungicide and selected after enrichment technique. Fungal strains were characterised by a polyphasic approach using phylogenetic analysis of the Internal Transcribed Spacer (ITS gene region, phenotypic characterisation by Matrix-Assisted Laser Desorption Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS spectral analysis, and growth kinetics experiments. The strains were identified as Gongronella sp. and Rhizopus oryzae. The fungal growth kinetics in liquid cultures containing metalaxyl fits with Haldane model. Under laboratory conditions, the ability of Gongronella sp. and R. oryzae cultures to degrade metalaxyl was evaluated in liquid cultures and soil experiments. Both species were able to: (a use metalaxyl as the main carbon and energy source; and (b degrade metalaxyl in polluted soils, with rates around 1.0 mg kg−1 d−1. This suggests these strains could degrade metalaxyl in soils contaminated with this fungicide.

  12. Enhancement of L(+)-Lactic Acid Production of Immobilized Rhizopus Oryzae Implanted by Ion Beams

    International Nuclear Information System (INIS)

    Fan Yonghong; Yang Yingge; Zheng Zhiming; Li Wen; Wang Peng; Yao Liming; Yu Zengliang

    2008-01-01

    Immobilized Rhizopus oryzae culturing may be a solution to the inhibited production of L(+)-lactic acid in submerged fermentation, which is caused by aggregated mycelia floc. In the present study, a R. oryzae mutant (RL6041) with a 90% conversion rate of glucose into L-lactic acid was obtained by N + implantation under the optimized conditions of a beam energy of 15 keV and a dose of 2.6 x 10 15 ions/cm 2 . Using polyurethane foam as the immobilization matrix, the optimal L-lactic acid production conditions were determined as 4 mm polyurethane foam, 150 r/min, 50 g/L ∼ 80 g/L of initial glucose, 38 deg. C and pH 6.0. 15-cycle repeated productions of L-lactic acid by immobilized RL6041 were performed under the optimized culturing conditions and over 80% of the glucose was converted into L-lactic acid in 30 hours on average. The results show that immobilized RL6041 is a promising candidate for continuous L-lactic acid production.

  13. High-level expression and characterization of a chimeric lipase from Rhizopus oryzae for biodiesel production

    OpenAIRE

    Yu, Xiao-Wei; Sha, Chong; Guo, Yong-Liang; Xiao, Rong; Xu, Yan

    2013-01-01

    Background Production of biodiesel from non-edible oils is receiving increasing attention. Tung oil, called ?China wood oil? is one kind of promising non-edible biodiesel oil in China. To our knowledge, tung oil has not been used to produce biodiesel by enzymatic method. The enzymatic production of biodiesel has been investigated extensively by using Rhizopus oryzae lipase as catalyst. However, the high cost of R. oryzae lipase remains a barrier for its industrial applications. Through differ...

  14. An unusual ulcer: A case of cutaneous mucormycosis caused by Rhizopus oryzae

    Directory of Open Access Journals (Sweden)

    Bradley J. Gardiner

    2015-03-01

    Full Text Available Mucormycoses are high-mortality infections feared by clinicians worldwide. They predominantly affect immunocompromised hosts and are associated with a spectrum of disease. We describe a case of cutaneous mucormycosis caused by Rhizopus oryzae in a patient with multiple risk factors cured with complete surgical excision and a short course of antifungal therapy.

  15. Fob1 and Fob2 Proteins Are Virulence Determinants of Rhizopus oryzae via Facilitating Iron Uptake from Ferrioxamine.

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    Mingfu Liu

    2015-05-01

    Full Text Available Dialysis patients with chronic renal failure receiving deferoxamine for treating iron overload are uniquely predisposed for mucormycosis, which is most often caused by Rhizopus oryzae. Although the deferoxamine siderophore is not secreted by Mucorales, previous studies established that Rhizopus species utilize iron from ferrioxamine (iron-rich form of deferoxamine. Here we determined that the CBS domain proteins of Fob1 and Fob2 act as receptors on the cell surface of R. oryzae during iron uptake from ferrioxamine. Fob1 and Fob2 cell surface expression was induced in the presence of ferrioxamine and bound radiolabeled ferrioxamine. A R. oryzae strain with targeted reduced Fob1/Fob2 expression was impaired for iron uptake, germinating, and growing on medium with ferrioxamine as the sole source of iron. This strain also exhibited reduced virulence in a deferoxamine-treated, but not the diabetic ketoacidotic (DKA, mouse model of mucormycosis. The mechanism by which R. oryzae obtains iron from ferrioxamine involves the reductase/permease uptake system since the growth on ferrioxamine supplemented medium is associated with elevated reductase activity and the use of the ferrous chelator bathophenanthroline disulfonate abrogates iron uptake and growth on medium supplemented with ferrioxamine as a sole source of iron. Finally, R. oryzae mutants with reduced copies of the high affinity iron permease (FTR1 or with decreased FTR1 expression had an impaired iron uptake from ferrioxamine in vitro and reduced virulence in the deferoxamine-treated mouse model of mucormycosis. These two receptors appear to be conserved in Mucorales, and can be the subject of future novel therapy to maintain the use of deferoxamine for treating iron-overload.

  16. Biosynthesis of tannase and gallic acid from tannin rich substrates by Rhizopus oryzae and Aspergillus foetidus.

    Science.gov (United States)

    Mukherjee, Gargi; Banerjee, Rintu

    2004-01-01

    Modified solid-state fermentation (MSSF) of tannin-rich substrates for production of tannase and gallic acid was carried out using two fungal cultures, Rhizopus oryzae (RO IIT RB-13, NRRL 21498) and Aspergillus foetidus (GMRB013 MTCC 3557). The tannin rich substrates included powdered fruits of Terminalia chebula and Caesalpinia digyna pod cover powder. The different environmental parameters for the maximum production of tannase and gallic acid were optimized through media engineering. The highest yield of tannase and gallic acid was obtained after 60 h in case of Rhizopus oryzae and after 72 h by Aspergillus foetidus with 3 ml of induced inoculum. The optimum initial pH of the fermentation was found to be 4.5 in case of Rhizopus oryzae and 5.0 for Aspergillus foetidus. MSSF was carried out at the optimum conditions of 30 degrees C and 80% relative humidity. Collectively, the data reveal the potential of the modified solid-state fermentation process for the production of tannase and gallic acid from tannin-rich substrates with R. oryzae and A. foetidus.

  17. Species boundaries and nomenclature of Rhizopus arrhizus (syn. R. oryzae)

    NARCIS (Netherlands)

    Dolatabadi, Somayeh; de Hoog, G Sybren; Meis, Jacques F; Walther, Grit

    2014-01-01

    Rhizopus arrhizus (Mucorales, Mucoromycotina) is the prevalent opportunist worldwide among the mucoralean species causing human infections. On the other hand the species has been used since ancient times to ferment African and Asian traditional foods and condiments based on ground soybeans. As

  18. Comparative study on the antifungal activity of hydroalcoholic extract of Iranian Propolis and Royal jelly against Rhizopus oryzae

    Directory of Open Access Journals (Sweden)

    Moghim Hassan

    2015-07-01

    Full Text Available Introduction: Mucormycosis is an opportunistic fungal infection. Rhizopus oryzae is major cause of mucormycosis in humans. This disease is the most common form of the acute fungal infection with rapid progress. Iranian Propolis extract and Royal jelly are honey bee products which have been used by human over the past centuries in traditional medicine. In this study the effects of Iranian Propolis and Royal jelly were investigated against Rhizopus oryzae and Candida albicans. Methods: The used method in this study was microdilution. To perform it, the prepared dilutions of Royal jelly and alcoholic extract of Iranian Propolis were added to tubes containing Sabouraud dextrose broth culture media except to control group and then Rhizopus oryzae suspension was added to all microtubes. In the next stage, microtubes were maintained in incubator at 25oC for 48 hours and then 10 ml of the content of each microtube was transferred to Sabouraud dextrose agar media. The minimum inhibitory concentration (MIC and minimum fungicidal concentration (MFC of the agents were calculated. Results: In this study, the MIC and MFC of Iranian Propolis alcoholic extract on Rhizopus oryzae were respectively 0.1 and 0.25 mg/ml and the MFC of Royal jelly on Rhizopus oryzae were respectively 100 ± 34 and 133 ± 46 mg/ml. Conclusion: The results indicate that Propolis might be used as an ideal combination for the treatment of fungal infections like Rhizopus oryzae. However, clinical studies are needed to confirm the effects of these drugs.

  19. KINETIC STUDY OF PALMITIC ACID ESTERIFICATION CATALYZED BY Rhizopus oryzae RESTING CELLS

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    JONH J MÉNDEZ

    2009-01-01

    Full Text Available ABSTRACT In the present study, a kinetic model for the biocatalytic synthesis of esters using Rhizopus oryzae resting cells is proposed. The kinetic study has been made in a range of 30-50 °C and atmospheric pressure. The Influence of operating variables, water content, pH, amount of mycelium was studied. Different values of temperature, initial mycelium concentration and acid/alcohol molar ratio were tested. Initial rates were estimated from the slope of the concentration of palmitic acid, or their corresponding ester at conversions of less than 10%, versus time and reported as mmol l-1 min -1. The values of kinetic constants were computed using the freeware program SIMFIT (http:\\\\www.simfit.man.ac.uk. Key words: bound lipase, esterification, fungal resting cells, Rhizopus oryzae, palmitic acid, propanol. RESUMEN En el presente estudio, un modelo cinético para la síntesis de esteres usando Rhizopus oryzae resting cells es propuesto. El estudio cinético fue realizado en un rango de temperatura de 30-50 ºC a presión atmosférica reducida. La influencia de las variables de operación tales como temperatura, pH y contenido de agua fueron estudiadas. Diferentes valores de concentración de micelio y relación molar de ácido/alcohol son ensayadas, Las velocidades iníciales se estimaron de la curva de concentración de acido palmítico, y su correspondiente conversión a ester en menos del 10%, frente a tiempo y reportadas en mmol I-1 min -1. Los valores de las constantes cinéticas fueron calculados usando el programa freeware SIMFIT (http:\\\\www.simfit.man.ac.uk. Palabras clave: Lipasas, esterificación, resting cells, Rhizopus oryzae, acido palmítico, propanol.

  20. Enhanced L-(+)-lactic acid production by an adapted strain of Rhizopus oryzae using corncob hydrolysate

    DEFF Research Database (Denmark)

    Bai, Dongmei; Li, S.Z.; Liu, Z.L.

    2008-01-01

    -added production of a variety of bioproducts. Lactic acid can be used as a precursor for poly-lactic acid production. Although current industrial lactic acid is produced by lactic acid bacteria using enriched medium, production by Rhizopus oryzae is preferred due to its exclusive formation of the......-isomer and a simple nutrition requirement by the fungus. Production of-L-(+)-lactic acid by R. oryzae using xylose has been reported; however, its yield and conversion rate are poor compared with that of using glucose. In this study, we report an adapted R. oryzae strain HZS6 that significantly improved efficiency...... of substrate utilization and enhanced production of L-(+)-lactic acid from corncob hydrolysate. It increased L-(+)-lactic acid final concentration, yield, and volumetric productivity more than twofold compared with its parental strain. The optimized growth and fermentation conditions for Strain HZS6 were...

  1. Promoter sequence of 3-phosphoglycerate kinase gene 1 of lactic acid-producing fungus rhizopus oryzae and a method of expressing a gene of interest in fungal species

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Johnway [Richland, WA; Skeen, Rodney S [Pendleton, OR

    2002-10-15

    The present invention provides the promoter clone discovery of phosphoglycerate kinase gene 1 of a lactic acid-producing filamentous fungal strain, Rhizopus oryzae. The isolated promoter can constitutively regulate gene expression under various carbohydrate conditions. In addition, the present invention also provides a design of an integration vector for the transformation of a foreign gene in Rhizopus oryzae.

  2. Promoter sequence of 3-phosphoglycerate kinase gene 2 of lactic acid-producing fungus rhizopus oryzae and a method of expressing a gene of interest in fungal species

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Johnway [Richland, WA; Skeen, Rodney S [Pendleton, OR

    2003-03-04

    The present invention provides the promoter clone discovery of phosphoglycerate kinase gene 2 of a lactic acid-producing filamentous fungal strain, Rhizopus oryzae. The isolated promoter can constitutively regulate gene expression under various carbohydrate conditions. In addition, the present invention also provides a design of an integration vector for the transformation of a foreign gene in Rhizopus oryzae.

  3. Effect of Rhizopus oryzae Fermentation on Kenaf-Based Polylactic Acid’s Monomer

    Directory of Open Access Journals (Sweden)

    Nur Aimi Mohd Nasir

    2011-12-01

    Full Text Available Kenaf biomass is the potential as raw materials used to produce polylactic acid's monomer which is lactic acid via fermentation by Rhizopus oryzae. Kenaf biomass' structure is complex due to its lignin and cellulose content. This matter had encouraged it to undergo pre- treatment process as the initial step before fermentation process can be done. In this paper, kenaf biomass was treated with dilute sulphuric acid (H2SO4 to hydrolyze the cellulose content in it as well as to convert the cellulose into glucose- a carbon source for Rhizopus to grow. Then, the fermentation process was carried out in shake flask for 3 days at pH 6. Several conditions for fermentation process had been chosen which were 25oC at 150 rpm, 25 oC at 200 rpm, 37 oC at 150 rpm and 37oC at 200 rpm. In this fermentation process, 0.471 g/L, 0.428 g/L, 0.444 g/L and 0.38 g/L of lactic acid was produced respectively. Sample at 25oC at 200 rpm produced maximum amount of lactic acid compared to others.ABSTRAK: Biojisim kenaf berpotensi sebagai bahan mentah dalam penghasilan monomer asid polylactic (poliester alifatik termoplastik diterbitkan daripada sumber boleh diperbaharu seperti kanji jagung yang merupakan asid laktik menerusi penapaian oleh Rhizopus oryzae (sejenis fungus yang hidup dalam jirim organik yang telah mati. Struktur biojisim kenaf adalah kompleks disebabkan kandungan lignin dan selulosanya. Hal ini menyebabkan ia perlu melalui proses pra-rawatan sebagai langkah awal sebelum proses penapaian dijalankan. Dalam kertas ini, biojirim kenaf dirawat dengan asid sulfurik (H2SO4 yang dicairkan untuk menghidrolisis kandungan selulosa di dalamnya di samping menukar selulosa menjadi glukosa - sumber karbon bagi tumbesaran Rhizopus. Kemudian, proses penapaian dijalankan di dalam kelalang goncang selama 3 hari pada pH 6. Beberapa ciri proses penapaian telah dipilih iaitu 25 oC pada 150 rpm, 25 oC pada 200 rpm, 37 oC pada 150 rpm dan 37 oC pada 200 rpm. Dalam proses penapaian

  4. Mitochondrial respiratory pathways inhibition in Rhizopus oryzae potentiates activity of posaconazole and itraconazole via apoptosis.

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    Fazal Shirazi

    Full Text Available The incidence of mucormycosis has increased drastically in immunocompromised patients. Also the array of targets whose inhibition results in Mucorales death is limited. Recently, researchers identified mitochondria as important regulators of detoxification and virulence mechanisms in fungi. In this context, targeting the mitochondrial respiratory chain may provide a new platform for antifungal development. We hypothesized that targeting respiratory pathways potentiates triazoles activity via apoptosis. We found that simultaneous administration of antimycin A (AA and benzohydroxamate (BHAM, inhibitors of classical and alternative mitochondrial pathways respectively, resulted in potent activity of posaconazole (PCZ and itraconazole (ICZ against Rhizopus oryzae. We observed cellular changes characteristic of apoptosis in R. oryzae cells treated with PCZ or ICZ in combination with AA and BHAM. The fungicidal activity of this combination against R. oryzae was correlated with intracellular reactive oxygen species accumulation (ROS, phosphatidylserine externalization, mitochondrial membrane depolarization, and increased caspase like activity. DNA fragmentation and condensation assays also revealed apoptosis of R. oryzae cells. These apoptotic features were prevented by the addition of the ROS scavenger N-acetyl-cysteine. Taken together, these findings suggest that the use of PCZ or ICZ in combination with AA and BHAM makes R. oryzae exquisitely sensitive to treatment with triazoles via apoptosis. This strategy may serve as a new model for the development of improved or novel antifungal agents.

  5. Inhibition of lipases from Chromobacterium viscosum and Rhizopus oryzae by tetrahydrolipstatin.

    Science.gov (United States)

    Potthoff, A P; Haalck, L; Spener, F

    1998-01-15

    Tetrahydrolipstatin is known as an inhibitor for pancreatic lipase but not for microbial lipases. In this paper we demonstrate that in the presence of water-insoluble substrates like tributyrin or olive oil, tetrahydrolipstatin inhibits the lipases of Chromobacterium viscosum and Rhizopus oryzae, although with different potency. In contrast to porcine pancreatic lipase, which forms an irreversible and covalent enzyme-inhibitor complex with tetrahydrolipstatin, the inhibition of the microbial lipases is reversible as the inhibitor can be removed from the enzyme-inhibitor complex by solvent extraction. Moreover, after inhibition of Chromobacterium viscosum lipase tetrahydrolipstatin remains chemically unchanged.

  6. Effect of Rhizopus oryzae Fermentation on Kenaf-Based Polylactic Acid’s Monomer

    OpenAIRE

    Nur Aimi Mohd Nasir; Mohd Adlan Mustafa Kamalbahrin; Nurhafizah Mohamad; Hazleen Anuar; Maizirwan Mel; and Rashidi Othman

    2011-01-01

    Kenaf biomass is the potential as raw materials used to produce polylactic acid's monomer which is lactic acid via fermentation by Rhizopus oryzae. Kenaf biomass' structure is complex due to its lignin and cellulose content. This matter had encouraged it to undergo pre- treatment process as the initial step before fermentation process can be done. In this paper, kenaf biomass was treated with dilute sulphuric acid (H2SO4) to hydrolyze the cellulose content in it as well as to convert the cell...

  7. Pyogenic liver abscess and peritonitis due to Rhizopus oryzae in a child with Papillon-Lefevre syndrome.

    Science.gov (United States)

    Dalgic, Buket; Bukulmez, Aysegul; Sari, Sinan

    2011-06-01

    Papillon-Lefevre syndrome (PLS) is an autosomal recessive disease that is characterized by symmetric palmoplantar keratodermatitis and severe periodontal destruction. Mutations in the cathepsin C gene (CTSC) have recently been detected in PLS. Immune dysregulation, due to a mutation in CTSC, increases the risk of pyogenic infections in PLS patients. A child with PLS is presented here with liver abscesses and peritonitis caused by Rhizopus oryzae. His liver abscess and peritonitis were cured with amphotericin B without surgical care. This is the first case in the literature liver abscess due to Rhizopus oryzae in a child with PLS.

  8. Evaluasi Perlakuan Pendahuluan Menggunakan Kalsium Hidroksida untuk Biokonversi Jerami Padi Menjadi L-Asam Laktat oleh Rhizopus oryzae AT3 (Evaluation of Lime Pretreatment for Bioconversion of Rice Straw to L-Lactic Acid by Rhizopus Oryzae AT3

    Directory of Open Access Journals (Sweden)

    Dhina Aprilia Nurani Widyahapsari

    2016-12-01

    Full Text Available L-lactic acid can be used as a precursor of polylactic acid (PLA. PLA is a biodegradable biomaterial commonly used for biodegradable plastics. Lactic acid can be produced from lignocelluloses materials such as rice straw. Rice straw is composed of cellulose and hemicellulose that can be hydrolyzed to fermentable sugar by cellulolytic and hemicellulolytic enzymes then converted to L-lactic acid by Rhizopus oryzae. As most cellulose and hemicellulose present in lignocellulose biomass are not readily accessible for these enzyme, pretreatment is required to alter the structure of lignocellulose substrates. This research aimed to investigate the effect of lime pretreatment on rice straw bioconversion to L-lactic acid by Rhizopus oryzae AT3. Rice straw was pretreated with lime (Ca(OH2 at 85 °C for 16 hours. Unpretreated and pretreated rice straw were hydrolyzed using crude enzyme that produced by Trichoderma reesei Pk1J2. Enzyme production was carried out by solid state fermentation using rice straw and rice brand as substrate. Enzymatic hydrolysis was carried out in flasks. Each flask was added with unpretreated or pretreated rice straw, buffer citrate solution and crude enzyme then hydrolyzed for 0-96 hours. Hydrolysate was fermented by Rhizopus oryzae AT3 for 0-6 days by using adsorbed carrier solid-state fermentation method with polyurethane foam as inert support material. Lime pretreatment at 85 °C for 16 hour led to significant solubilisation of lignin and hemicellulose. It involved lignocellulose structure modified that enhance enzymatic hydrolysis and resulted higher reducing sugars than unpretreated rice straw. The high reducing sugars was not related to high lactic acid yields. Fermentation of pretreated rice straw hydrolysate by Rhizopus oryzae AT3 did not only produce L-lactic acid but also other compound. On the other hand, fermentation of unpretreated rice straw hydrolysate only produced L-lactic acid.   ABSTRAK Polimerisasi asam

  9. Rhizopus oryzae - Ancient microbial resource with importance in modern food industry.

    Science.gov (United States)

    Londoño-Hernández, Liliana; Ramírez-Toro, Cristina; Ruiz, Héctor A; Ascacio-Valdés, Juan A; Aguilar-Gonzalez, Miguel A; Rodríguez-Herrera, Raúl; Aguilar, Cristóbal N

    2017-09-18

    Filamentous fungi are microorganisms widely known for their diverse biochemical features. Fungi can efficiently invade a wide variety of substrates under operational conditions producing numerous bioproducts of interest, such as enzymes, organic acids, aromatic compounds and colorants. An additional interesting characteristic of some fungi is their safety classification for different uses, which guarantees that the bioproducts obtained from them do not contain any toxic component deleterious to humans. Rhizopus oryzae is among this group of fungi and is classified as a GRAS filamentous fungus, commonly used for production of some oriental traditional foods. It is mainly recognized as a good producer of lactic acid; however, its potential for other biotechnological processes is under study. This review analyzes and discusses the current scientific and technical contributions which may maximize the potential of R. oryzae as a producer of different compounds of industrial interest. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Damage to Aspergillus fumigatus and Rhizopus oryzae Hyphae by Oxidative and Nonoxidative Microbicidal Products of Human Neutrophils In Vitro

    OpenAIRE

    Diamond, Richard D.; Clark, Robert A.

    1982-01-01

    Our previous studies established that human neutrophils could damage and probably kill hyphae of Aspergillus fumigatus and Rhizopus oryzae in vitro, primarily by oxygen-dependent mechanisms active at the cell surface. These studies were extended, again quantitating hyphal damage by reduction in uptake of 14C-labeled uracil or glutamine. Neither A. fumigatus nor R. oryzae hyphae were damaged by neutrophils from patients with chronic granulomatous disease, confirming the importance of oxidative...

  11. Structure, function, and phylogeny of the mating locus in the Rhizopus oryzae complex.

    Directory of Open Access Journals (Sweden)

    Andrii P Gryganskyi

    2010-12-01

    Full Text Available The Rhizopus oryzae species complex is a group of zygomycete fungi that are common, cosmopolitan saprotrophs. Some strains are used beneficially for production of Asian fermented foods but they can also act as opportunistic human pathogens. Although R. oryzae reportedly has a heterothallic (+/- mating system, most strains have not been observed to undergo sexual reproduction and the genetic structure of its mating locus has not been characterized. Here we report on the mating behavior and genetic structure of the mating locus for 54 isolates of the R. oryzae complex. All 54 strains have a mating locus similar in overall organization to Phycomyces blakesleeanus and Mucor circinelloides (Mucoromycotina, Zygomycota. In all of these fungi, the minus (- allele features the SexM high mobility group (HMG gene flanked by an RNA helicase gene and a TP transporter gene (TPT. Within the R. oryzae complex, the plus (+ mating allele includes an inserted region that codes for a BTB/POZ domain gene and the SexP HMG gene. Phylogenetic analyses of multiple genes, including the mating loci (HMG, TPT, RNA helicase, ITS1-5.8S-ITS2 rDNA, RPB2, and LDH genes, identified two distinct groups of strains. These correspond to previously described sibling species R. oryzae sensu stricto and R. delemar. Within each species, discordant gene phylogenies among multiple loci suggest an outcrossing population structure. The hypothesis of random-mating is also supported by a 50:50 ratio of plus and minus mating types in both cryptic species. When crossed with tester strains of the opposite mating type, most isolates of R. delemar failed to produce zygospores, while isolates of R. oryzae produced sterile zygospores. In spite of the reluctance of most strains to mate in vitro, the conserved sex locus structure and evidence for outcrossing suggest that a normal sexual cycle occurs in both species.

  12. Cosmeceutical potentials and bioactive compounds of rice bran fermented with single and mix culture of Aspergillus oryzae and Rhizopus oryzae

    Directory of Open Access Journals (Sweden)

    Dang Lelamurni Abd Razak

    2017-04-01

    Full Text Available In the present study, rice bran, one of the most abundant agricultural by-products in Malaysia, was fermented with single and mixed cultures of Aspergillus oryzae and Rhizopus oryzae. The fermented rice bran extracts were tested for their functional properties and compared to the non-fermented counterparts. Antioxidant activities as well as phenolics and organic acid contents were evaluated. Skincare-related functionalities were also tested by evaluating tyrosinase and elastase inhibition activities. Tyrosinase inhibition activity, measured to determine the anti-pigmentation effect of extracts, was found to be the highest in the extract of rice bran fermented with A. oryzae (56.18% compared to other extracts. In determining the anti-aging effect of fermented rice bran extracts, the same extract showed the highest elastase inhibition activity with a value of 60.52%. Antioxidant activities were found to be highest in the mix-cultured rice bran extract. The results of phenolic and organic acid content were varied; the major phenolic acid detected was ferulic acid with a value of 43.19 μg/ml in the mix-cultured rice bran extract. On the other hand, citric acid was the major organic acid detected, with the highest content found in the same extract (214.6 mg/g. The results of this study suggest that the fermented rice bran extracts may have the potential to be further exploited as ingredients in cosmetics as well as in antioxidant-rich products.

  13. High-level expression and characterization of a chimeric lipase from Rhizopus oryzae for biodiesel production.

    Science.gov (United States)

    Yu, Xiao-Wei; Sha, Chong; Guo, Yong-Liang; Xiao, Rong; Xu, Yan

    2013-02-21

    Production of biodiesel from non-edible oils is receiving increasing attention. Tung oil, called "China wood oil" is one kind of promising non-edible biodiesel oil in China. To our knowledge, tung oil has not been used to produce biodiesel by enzymatic method. The enzymatic production of biodiesel has been investigated extensively by using Rhizopus oryzae lipase as catalyst. However, the high cost of R. oryzae lipase remains a barrier for its industrial applications. Through different heterologous expression strategies and fermentation techniques, the highest expression level of the lipase from R. oryzae reached 1334 U/mL in Pichia pastoris, which is still not optimistic for industry applications. The prosequence of lipases from Rhizopus sp. is very important for the folding and secretion of an active lipase. A chimeric lipase from R. oryzae was constructed by replacing the prosequence with that from the R. chinensis lipase and expressed in P. pastoris. The maximum activity of the chimera reached 4050 U/mL, which was 11 fold higher than that of the parent. The properties of the chimera were studied. The immobilized chimera was used successfully for biodiesel production from tung oil, which achieved higher FAME yield compared with the free chimeric lipase, non-chimeric lipase and mature lipase. By response surface methodology, three variables, water content, methanol to tung oil molar ratio and enzyme dosage were proved to be crucial parameters for biosynthesis of FAME and the FAME yield reached 91.9±2.5% at the optimized conditions by adding 5.66 wt.% of the initial water based on oil weight, 3.88 of methanol to tung oil molar ratio and 13.24 wt.% of enzyme concentration based on oil weight at 40°C. This is the first report on improving the expression level of the lipase from R. oryzae by replacing prosequences. The immobilized chimera was used successfully for biodiesel production from tung oil. Using tung oil as non-edible raw material and a chimeric lipase

  14. Producing biodiesel from cotton seed oil using Rhizopus oryzae ATTC #34612 whole cell biocatalysts: Culture media and cultivation period optimization

    Science.gov (United States)

    The effect of culture medium composition and cultivation time on biodiesel production by Rhizopus oryzae ATCC #34612 whole cell catalysts, immobilized on novel rigid polyethylene biomass supports, was investigated. Supplementation of the medium with carbon sources led to higher lipase activity and i...

  15. Development of a system for integrative and stable transformation of the zygomycete Rhizopus oryzae by Agrobacterium-mediated DNA transfer

    NARCIS (Netherlands)

    Michielse, C.B.; Salim, K.; Ragas, P.; Ram, A.F.J.; Kudla, B.; Jarry, B.; Punt, P.J.; Hondel, C.A.M.J.J. van den

    2004-01-01

    Two transformation systems, based on the use of CaCl2/PEG and Agrobacterium tumefaciens, respectively, were developed for the zygomycete Rhizopus oryzae. Irrespective of the selection marker used, a pyr4 marker derived from R. niveus or a dominant amdS+ marker from Aspergillus nidulans, and

  16. Influence of rice straw-derived dissolved organic matter on lactic acid fermentation by Rhizopus oryzae.

    Science.gov (United States)

    Chen, Xingxuan; Wang, Xiahui; Xue, Yiyun; Zhang, Tian-Ao; Li, Yuhao; Hu, Jiajun; Tsang, Yiu Fai; Zhang, Hongsheng; Gao, Min-Tian

    2018-01-31

    Rice straw can be used as carbon sources for lactic acid fermentation. However, only a small amount of lactic acid is produced even though Rhizopus oryzae can consume glucose in rice straw-derived hydrolysates. This study correlated the inhibitory effect of rice straw with rice straw-derived dissolved organic matter (DOM). Lactic acid fermentations with and without DOM were conducted to investigate the effect of DOM on lactic acid fermentation by R. oryzae. Fermentation using control medium with DOM showed a similar trend to fermentation with rice straw-derived hydrolysates, showing that DOM contained the major inhibitor of rice straw. DOM assay indicated that it mainly consisted of polyphenols and polysaccharides. The addition of polyphenols and polysaccharides derived from rice straw confirmed that lactic acid fermentation was promoted by polysaccharides and significantly inhibited by polyphenols. The removal of polyphenols also improved lactic acid production. However, the loss of polysaccharides during the removal of polyphenols resulted in low glucose consumption. This study is the first to investigate the effects of rice straw-derived DOM on lactic acid fermentation by R. oryzae. The results may provide a theoretical basis for identifying inhibitors and promoters associated with lactic acid fermentation and for establishing suitable pretreatment methods. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  17. Optimization of xylanase production by Mucor indicus, Mucor hiemalis, and Rhizopus oryzae through solid state fermentation

    Directory of Open Access Journals (Sweden)

    Sanaz Behnam

    2016-03-01

    Full Text Available Introduction: Xylan is the main hemicellulosic polymer in a number of lignocelluloses which can be hydrolyzed by xylanolytic enzymes. One of the main ways for enzymes production is solid state fermentation (SSF. The ability of three fungal strains (Mucor indicus, Mucor hiemalis, and Rhizopus oryzae for xylanase production on wheat bran by SSF was investigated. Materials and methods: The effects of cultivation temperature, medium moisture content, and cultivation time on the enzyme production were investigated. Experiments were designed with an orthogonal central composite design on three variables using response surface methodology (RSM. Analysis of variance was applied and the enzyme production was expressed with a mathematical equation as a function of the three factors. The optimum operating conditions for the enzyme production was obtained. Results: For xylanase production by M. indicus, M. hiemalis and R. oryzae the optimum temperatures were 40.0, 43.4 and 43.4ºC respectively. These values were 49.8, 54.2 and 71.8% for moisture percent and 51.3, 53.2 and 53.5 h for cultivation time. The highest enzyme activities per g of dry substrate (gds were 43.1, 43.8 and 25.9 U/gds for M. indicus, M. hiemalis and R. oryzae respectively. Discussion and conclusion: All the fungi were able to produce xylanase. Maximum xylanase production was predicted by M. indicus and M. hiemalis at similar optimum conditions, while R. oryzae produced relatively lower xylanase activity even at the best condition. 

  18. In vitro antifungal susceptibility of clinical species belonging to Aspergillus genus and Rhizopus oryzae.

    Science.gov (United States)

    Kachuei, R; Khodavaisy, S; Rezaie, S; Sharifynia, S

    2016-03-01

    Among filamentous fungal pathogens, Aspergillus spp. and zygomycetes account for highest rates of morbidity and mortality among immunocompromised patients. Recently developed antifungal drugs offer the potential to improve management and therapeutic outcomes of fungal infections. The aim of this study was to analyse the in vitro activities of voriconazole, itraconazole, amphotericin B and caspofungin against clinical isolates of Aspergillus spp. and Rhizopus oryzae. The in vitro antifungal susceptibility of 54 isolates belonging to different clinical isolates of Aspergillus spp. and R. oryzae was tested for four antifungal agents using a microdilution reference method (CLSI, M38-A2). All isolates were identified by typical colony and microscopic characteristics, and also characterized by molecular methods. Caspofungin (MEC range: 0.008-0.25 and MEC50: 0.0023μg/mL) was the most active drug in vitro against Aspergillus spp., followed by voriconazole (MIC range: 0.031-8 and MIC50: 0.5μg/mL), itraconazole (MIC range: 0.031-16 and MIC50: 0.25μg/mL), and amphotericin B (MIC range: 0.125-4 and MIC50: 0.5μg/mL), in order of decreasing activity. The caspofungin, voriconazole, and itraconazole demonstrated poor in vitro activity against R. oryzae isolates evaluated, followed by amphotericin B. This study demonstrates that caspofungin had good antifungal activity and azole agents had better activity than amphotericin B against Aspergillus species. Although, azole drugs are considered ineffective against R. oryzae. This result is just from a small scale in vitro susceptibility study and we did not take other factors into consideration. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  19. The Production of Biodiesel from Cottonseed Oil Using Rhizopus oryzae Whole Cell Biocatalysts

    Science.gov (United States)

    Athalye, Sneha Kishor

    Biodiesel is an environmentally friendly alternative to fossil fuels which have become increasingly expensive in recent times. An alternate approach to alkaline biodiesel production is needed as catalyst miscibility with the glycerol by-product, generation of large amounts of waste water, and saponification of the feedstock are major disadvantages associated with the process. Lipases are water soluble enzymes which act as catalysts in many lipid based reactions. Reuse of lipases can significantly reduce cost of enzymatic biodiesel production; however retention of lipolytic activity still remains a challenge. Use of microbial cells immobilized on various surfaces like sponge, foam and plastics as biocatalysts instead of extracted enzyme could help overcome this problem. A novel, rigid biomass support with high surface area made from recyclable polyethylene (Bioblok(TM)) was used in this study. Several fungal and bacterial species have been reported to possess appreciable levels of lipase activity. The biomass production and immobilization as well as lipase activity of three different species; Candida rugosa (ATCC #38772), Aspergillus oryzae (ATCC #58299), and Rhizopus oryzae (ATTC #34612) were tested. C. rugosa did not attach well to the support particles while A.oryzae had lower biomass accumulation of 6.1 g (dry cell wt)/L compared to 11.8 g (dry cell wt)/L for R.oryzae. Hence Rhizopus oryzae, fungal specie with cell surface bound lipase was selected for the current study. The study investigated the influence of media composition and growth time of the R.oryzae whole cell biocatalysts, immobilized on the BSPs, for FAME production from cottonseed oil. R.oryzae BSPs grown in basal media supplemented with 1% (w/v) of glucose or oil or both for 48 h, 72 h or 90 h were used in a 36 h transesterification reaction with cottonseed oil and methanol. BSPs grown in both glucose and oil supplemented medium for 72 h had the highest conversion of 22.4% (wt/wt) and a biomass

  20. Protein concentrations of sweet soysauces from Rhizopus oryzae and R. oligosporus fermentation without moromi fermentation

    Directory of Open Access Journals (Sweden)

    NOOR SOESANTI HANDAJANI

    2007-07-01

    Full Text Available Soy sauce was produce from soybean that fermented with koji/tempeh fungi and thenfermented under salt solution or moromi fermentation. The objectives of this experiment was to compare of protein (total and soluble content of sweet soy sauce that produced from soybean fermented with Rhizopus oryzae and R. oligosporus without moromi fermentation to the sweet soysauce with moromi fermentation one. The total and soluble proteins of sweet soy sauces that produce from soybean without moromi fermentation were higher that sweet soy sauces that produce with moromi fermentation. Soluble protein of sweet soy sauce that produced from soybean fermented with R. oligosporus without moromi fermentation was 8.2% and meet to the highest quality of sweet soy sweet sauce based on Indonesia Industrial Standard. Soluble protein of sweet soy sauce that produced from soybean fermented with R. oryzae without moromi fermentation was 4.1% and meet to the medium quality of sweet soy sweet sauce based on Indonesia Industrial Standard.

  1. Ethanol production by Mucor indicus and Rhizopus oryzae from rice straw by separate hydrolysis and fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Abedinifar, Sorahi [Department of Chemical Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran); Karimi, Keikhosro [Department of Chemical Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran); School of Engineering, University of Boraas, SE-501 90 Boraas (Sweden); Khanahmadi, Morteza [Isfahan Agriculture and Natural Resources Research Centre, Isfahan (Iran); Taherzadeh, Mohammad J. [School of Engineering, University of Boraas, SE-501 90 Boraas (Sweden)

    2009-05-15

    Rice straw was successfully converted to ethanol by separate enzymatic hydrolysis and fermentation by Mucor indicus, Rhizopus oryzae, and Saccharomyces cerevisiae. The hydrolysis temperature and pH of commercial cellulase and {beta}-glucosidase enzymes were first investigated and their best performance obtained at 45 C and pH 5.0. The pretreatment of the straw with dilute-acid hydrolysis resulted in 0.72 g g{sup -1} sugar yield during 48 h enzymatic hydrolysis, which was higher than steam-pretreated (0.60 g g{sup -1}) and untreated straw (0.46 g g{sup -1}). Furthermore, increasing the concentration of the dilute-acid pretreated straw from 20 to 50 and 100 g L{sup -1} resulted in 13% and 16% lower sugar yield, respectively. Anaerobic cultivation of the hydrolyzates with M. indicus resulted in 0.36-0.43 g g{sup -1} ethanol, 0.11-0.17 g g{sup -1} biomass, and 0.04-0.06 g g{sup -1} glycerol, which is comparable with the corresponding yields by S. cerevisiae (0.37-0.45 g g{sup -1} ethanol, 0.04-0.10 g g{sup -1} biomass and 0.05-0.07 glycerol). These two fungi produced no other major metabolite from the straw and completed the cultivation in less than 25 h. However, R. oryzae produced lactic acid as the major by-product with yield of 0.05-0.09 g g{sup -1}. This fungus had ethanol, biomass and glycerol yields of 0.33-0.41, 0.06-0.12, and 0.03-0.04 g g{sup -1}, respectively. (author)

  2. Extra-cellular isoamylase production by Rhizopus oryzae in solid-state fermentation of agro wastes

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    Barnita Ghosh

    2011-10-01

    Full Text Available Extra-cellular isoamylase was produced by Rhizopus oryzae PR7 in solid-state fermentations of various agro wastes, among which millet, oat, tapioca, and arum (Colocasia esculenta showed promising results. The highest amount of enzyme production was obtained after 72 h of growth at 28°C. The optimum pH for enzyme production was - 8.0. Among the various additives tested, enzyme production increased with ions such as Ca2+, Mg2+ and also with cysteine, GSH, and DTT. The enzyme synthesis was reduced in the presence of thiol inhibitors like Cu2+ and pCMB. The surfactants like Tween-40, Tween-80 and Triton X-100 helped in enhancing the enzyme activity. The production could be further increased by using the combinations of substrates. The ability to produce high amount of isoamylase within a relatively very short period and the capability of degrading wastes could make the strain suitable for commercial production of the enzyme.

  3. Kinetics Study of Extracellular Detergent Stable Alkaline Protease from Rhizopus oryzae

    Directory of Open Access Journals (Sweden)

    Zareena Mushtaq

    2015-04-01

    Full Text Available In this study, extracellular alkaline protease was produced from Rhizopus oryzae in submerged fermentation using dairy waste (whey as a substrate. Fermentation kinetics was studied and various parameters were optimized. The strain produced maximum protease at initial medium pH of 6.0 medium depth of 26 mm, inoculum size of 2% at incubation temperature of 35ºC for 168 h of fermentation. Alkaline protease was purified to homogeneity by ammonium sulphate fractionation followed by sephadex G-100 chromatography. The molecular mass of alkaline protease was 69 kDa determined by 10% SDS-PAGE. The optimum pH and temperature of alkaline protease was 9.0 and 40ºC, respectively. Metal profile of the enzyme showed that the enzyme was non-metallic in nature. The Km , Kcat , Vmax and Kcat/Km values of purified protease were 7.0 mg/mL, 3.8 x102S-1, 54.30 µmol/min and 54.28 s-1mg -1.mL respectively, using casein as substrate. The purified alkaline protease had stability with commercial detergents.

  4. Construction of the yeast whole-cell Rhizopus oryzae lipase biocatalyst with high activity.

    Science.gov (United States)

    Chen, Mei-ling; Guo, Qin; Wang, Rui-zhi; Xu, Juan; Zhou, Chen-wei; Ruan, Hui; He, Guo-qing

    2011-07-01

    Surface display is effectively utilized to construct a whole-cell biocatalyst. Codon optimization has been proven to be effective in maximizing production of heterologous proteins in yeast. Here, the cDNA sequence of Rhizopus oryzae lipase (ROL) was optimized and synthesized according to the codon bias of Saccharomyces cerevisiae, and based on the Saccharomyces cerevisiae cell surface display system with α-agglutinin as an anchor, recombinant yeast displaying fully codon-optimized ROL with high activity was successfully constructed. Compared with the wild-type ROL-displaying yeast, the activity of the codon-optimized ROL yeast whole-cell biocatalyst (25 U/g dried cells) was 12.8-fold higher in a hydrolysis reaction using p-nitrophenyl palmitate (pNPP) as the substrate. To our knowledge, this was the first attempt to combine the techniques of yeast surface display and codon optimization for whole-cell biocatalyst construction. Consequently, the yeast whole-cell ROL biocatalyst was constructed with high activity. The optimum pH and temperature for the yeast whole-cell ROL biocatalyst were pH 7.0 and 40 °C. Furthermore, this whole-cell biocatalyst was applied to the hydrolysis of tributyrin and the resulted conversion of butyric acid reached 96.91% after 144 h.

  5. Chitosan production by psychrotolerant Rhizopus oryzae in non-sterile open fermentation conditions.

    Science.gov (United States)

    Tasar, Ozden Canli; Erdal, Serkan; Taskin, Mesut

    2016-08-01

    A new chitosan producing fungus was locally isolated from soil samples collected around Erzurum, Turkey and identified as Rhizopus oryzae PAS 17 (GenBank accession number KU318422.1). Cultivation in low cost non-sterile conditions was achieved by exploiting its ability to grow at low temperature and pH, thus, undesired microbial contamination could be eliminated when appropriate culture conditions (incubation temperature as 15°C and initial pH of the medium as 4.5) were selected. Medium composition and culture conditions were optimized using Taguchi orthogonal array (OA) design of experiment (DOE). An OA layout of L16 (4(5)) was constructed with five most influensive factors at four levels on chitosan production like, carbon source (molasses), metal ion (Mg(2+)), inoculum amount, agitation speed and incubation time. The optimal combinations of factors (molasses, 70ml/l; MgSO4·7H2O, 0.5g/l; inoculum, 6.7×10(6) spores/disc; agitation speed, 150rpm and incubation time, 8days) obtained from the proposed DOE methodology was further validated by analysis of variance (ANOVA) test and the results revealed the increment of chitosan and biomass yields of 14.45 and 8.58 folds from its unoptimized condition, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Biodiesel production from Nannochloropsis gaditana lipids through transesterification catalyzed by Rhizopus oryzae lipase.

    Science.gov (United States)

    Navarro López, Elvira; Robles Medina, Alfonso; González Moreno, Pedro Antonio; Esteban Cerdán, Luis; Martín Valverde, Lorena; Molina Grima, Emilio

    2016-03-01

    Biodiesel (fatty acid methyl esters, FAMEs) was produced from saponifiable lipids (SLs) extracted from wet Nannochloropsis gaditana biomass using methanolysis catalyzed by Rhizopus oryzae intracellular lipase. SLs were firstly extracted with ethanol to obtain 31 wt% pure SLs. But this low SL purity also gave a low biodiesel conversion (58%). This conversion increased up to 80% using SLs purified by crystallization in acetone (95 wt% purity). Polar lipids play an important role in decreasing the reaction velocity - using SLs extracted with hexane, which have lower polar lipid content (37.4% versus 49.0% using ethanol), we obtained higher reaction velocities and less FAME conversion decrease when the same lipase batch was reused. 83% of SLs were transformed to biodiesel using a 70 wt% lipase/SL ratio, 11:1 methanol/SL molar ratio, 10 mL t-butanol/g SLs after 72 h. The FAME conversion decreased to 71% after catalyzing three reactions with the same lipase batch. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. L-lactic acid production by Aspergillus brasiliensis overexpressing the heterologous ldha gene from Rhizopus oryzae.

    Science.gov (United States)

    Liaud, Nadège; Rosso, Marie-Noëlle; Fabre, Nicolas; Crapart, Sylvaine; Herpoël-Gimbert, Isabelle; Sigoillot, Jean-Claude; Raouche, Sana; Levasseur, Anthony

    2015-05-03

    Lactic acid is the building block of poly-lactic acid (PLA), a biopolymer that could be set to replace petroleum-based plastics. To make lactic acid production cost-effective, the production process should be carried out at low pH, in low-nutrient media, and with a low-cost carbon source. Yeasts have been engineered to produce high levels of lactic acid at low pH from glucose but not from carbohydrate polymers (e.g. cellulose, hemicellulose, starch). Aspergilli are versatile microbial cell factories able to naturally produce large amounts of organic acids at low pH and to metabolize cheap abundant carbon sources such as plant biomass. However, they have never been used for lactic acid production. To investigate the feasibility of lactic acid production with Aspergillus, the NAD-dependent lactate dehydrogenase (LDH) responsible for lactic acid production by Rhizopus oryzae was produced in Aspergillus brasiliensis BRFM103. Among transformants, the best lactic acid producer, A. brasiliensis BRFM1877, integrated 6 ldhA gene copies, and intracellular LDH activity was 9.2 × 10(-2) U/mg. At a final pH of 1.6, lactic acid titer reached 13.1 g/L (conversion yield: 26%, w/w) at 138 h in glucose-ammonium medium. This extreme pH drop was subsequently prevented by switching nitrogen source from ammonium sulfate to Na-nitrate, leading to a final pH of 3 and a lactic acid titer of 17.7 g/L (conversion yield: 47%, w/w) at 90 h of culture. Final titer was further improved to 32.2 g/L of lactic acid (conversion yield: 44%, w/w) by adding 20 g/L glucose to the culture medium at 96 h. This strain was ultimately able to produce lactic acid from xylose, arabinose, starch and xylan. We obtained the first Aspergillus strains able to produce large amounts of lactic acid by inserting recombinant ldhA genes from R. oryzae into a wild-type A. brasiliensis strain. pH regulation failed to significantly increase lactic acid production, but switching nitrogen source and changing culture feed

  8. Role of N-terminal 28-amino-acid region of Rhizopus oryzae lipase in directing proteins to secretory pathway of Aspergillus oryzae.

    Science.gov (United States)

    Hama, Shinji; Tamalampudi, Sriappareddy; Shindo, Naoki; Numata, Takao; Yamaji, Hideki; Fukuda, Hideki; Kondo, Akihiko

    2008-07-01

    To develop a new approach for improving heterologous protein production in Aspergillus oryzae, we focused on the functional role of the N-terminal region of Rhizopus oryzae lipase (ROL). Several N-terminal deletion variants of ROL were expressed in A. oryzae. Interestingly, a segment of 28 amino acids from the C-terminal region of the propeptide (N28) was found to be critical for secretion of ROL into the culture medium. To further investigate the role of N28, the ROL secretory process was visualized in vivo using ROL-green fluorescent protein (GFP) fusion proteins. In cells producing ROL with N28, fluorescence observations showed that the fusion proteins are transported through endoplasmic reticulum (ER), Golgi, and cell wall, which is one of the typical secretory processes in a eukaryotic cell. Because the expression of the mature ROL-GFP fusion protein induced fluorescence accumulation without its translocation into the ER, N28 is considered to play a crucial role in protein transport. When N28 was inserted between the secretion signal and GFP, fluorescence observations showed that GFP, which is originally a cytoplasmic protein, was efficiently translocated into the ER of A. oryzae, resulting in an enhanced secretion of mature GFP after proteolytic cleavage of N28. These findings suggest that N28 facilitates protein translocation into ER and can be a promising candidate for improving heterologous protein production in A. oryzae.

  9. Rhizopus oryzae hyphae are damaged by human natural killer (NK) cells, but suppress NK cell mediated immunity.

    Science.gov (United States)

    Schmidt, Stanislaw; Tramsen, Lars; Perkhofer, Susanne; Lass-Flörl, Cornelia; Hanisch, Mitra; Röger, Frauke; Klingebiel, Thomas; Koehl, Ulrike; Lehrnbecher, Thomas

    2013-07-01

    Mucormycosis has a high mortality and is increasingly diagnosed in hematopoietic stem cell transplant (HSCT) recipients. In this setting, there is a growing interest to restore host defense to combat infections by adoptively transferring donor-derived immunocompetent cells. Natural killer (NK) cells exhibit antitumor and antiinfective activity, but the interaction with Mucormycetes is unknown. Our data demonstrate that both unstimulated and IL-2 prestimulated human NK cells damage Rhizopus oryzae hyphae, but do not affect resting conidia. The damage of the fungus is mediated, at least in part, by perforin. R. oryzae hyphae decrease the secretion of immunoregulatory molecules by NK cells, such as IFN-γ and RANTES, indicating an immunosuppressive effect of the fungus. Our data indicate that NK cells exhibit activity against Mucormycetes and future research should evaluate NK cells as a potential tool for adoptive immunotherapy in HSCT. Copyright © 2012 Elsevier GmbH. All rights reserved.

  10. Antifungal Activity of Colistin against Mucorales Species In Vitro and in a Murine Model of Rhizopus oryzae Pulmonary Infection▿

    Science.gov (United States)

    Ben-Ami, Ronen; Lewis, Russell E.; Tarrand, Jeffrey; Leventakos, Konstantinos; Kontoyiannis, Dimitrios P.

    2010-01-01

    In immunosuppressed hosts, mucormycosis is a life-threatening infection with few treatment options. We studied the activity of colistin (polymyxin E) against Mucorales species in vitro and in a murine model of pulmonary Rhizopus oryzae infection. Colistin exhibited fungicidal activity in vitro against Mucorales spores and mycelia. At the colistin MIC, initial R. oryzae hyphal damage was followed by rapid regrowth; however, regrowth was prevented by combining colistin with a subinhibitory concentration of amphotericin B. Using electron microscopy and FM4-64 staining, we demonstrated that colistin disrupts R. oryzae cytoplasmic and vacuolar membranes, resulting in the leakage of intracellular contents. The prophylactic intranasal treatment of immunosuppressed mice with colistimethate significantly reduced the mortality rate and pulmonary fungal burden resulting from inhalational challenge with R. oryzae spores, whereas intraperitoneal colistimethate treatment had no effect. We conclude that colistin has modest in vitro and in vivo fungicidal activity against Mucorales spp. Further studies are warranted to assess the use of this drug in the prevention and treatment of mucormycosis. PMID:19858263

  11. Antifungal activity of colistin against mucorales species in vitro and in a murine model of Rhizopus oryzae pulmonary infection.

    Science.gov (United States)

    Ben-Ami, Ronen; Lewis, Russell E; Tarrand, Jeffrey; Leventakos, Konstantinos; Kontoyiannis, Dimitrios P

    2010-01-01

    In immunosuppressed hosts, mucormycosis is a life-threatening infection with few treatment options. We studied the activity of colistin (polymyxin E) against Mucorales species in vitro and in a murine model of pulmonary Rhizopus oryzae infection. Colistin exhibited fungicidal activity in vitro against Mucorales spores and mycelia. At the colistin MIC, initial R. oryzae hyphal damage was followed by rapid regrowth; however, regrowth was prevented by combining colistin with a subinhibitory concentration of amphotericin B. Using electron microscopy and FM4-64 staining, we demonstrated that colistin disrupts R. oryzae cytoplasmic and vacuolar membranes, resulting in the leakage of intracellular contents. The prophylactic intranasal treatment of immunosuppressed mice with colistimethate significantly reduced the mortality rate and pulmonary fungal burden resulting from inhalational challenge with R. oryzae spores, whereas intraperitoneal colistimethate treatment had no effect. We conclude that colistin has modest in vitro and in vivo fungicidal activity against Mucorales spp. Further studies are warranted to assess the use of this drug in the prevention and treatment of mucormycosis.

  12. Isolation and optimization of pectinase enzyme production one of useful industrial enzyme in Aspergillus niger, Rhizopus oryzae, Penicilium chrysogenum

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    akram songol

    2016-06-01

    Full Text Available Introduction: Pectinase enzyme is one of the most important industrial enzymes which isolated from a wide variety of microorganisms such as bacteria and filamentous fungi. This enzyme has been usually used in the fruit and textile industry. In this study, the isolation and optimization of pectinase-producing fungi on decaying rotten fruits were studied. Materials and methods: Isolation and screening of pectinase producing fungi performed through plate culture on pectin medium and staining with Lugol's iodine solution. The best strains were identified by ITS1, 4 sequencing as Aspergillus fumigatus, Rhizopus oryzae, Penicilium chrysogenum. The enzyme production was optimized by application of the five factorial design, each at three levels. These factors are carbon sources (whey, glucose and stevia, ammonium sulfate, manganese sulfate, temperature, and pH. Pectinase concentration was measured by the Miller method. Results: The results indicate that optimum condition for enzyme production for three fungi strains was obtained at 32 °C, pH = 6, 3g / L manganese sulfate, 2.75g / L of ammonium sulfate and 10g / L of each carbon source. The best experiment in obtaining the optimum enzyme contained 1.328 mg / ml of glucose for Aspergillus niger 1.284 and 1.039 mg / ml of whey for Rhizopus oryzae and Penicilium chrysogenum. Molecular weight of enzyme was about 40 and 37 kDa which was obtained by SDS- PAGE. Discussion and conclusion: The results indicate that three strains could grow in a wide range of carbon source, pH and temperature, which could be a good candidate for industrial application.

  13. Possible pulmonary Rhizopus oryzae infection in a previously healthy child after a near-drowning incident.

    Science.gov (United States)

    Gerlach, Magdalena M; Lippmann, Norman; Kobelt, Louise; Petzold-Quinque, Stefanie; Ritter, Lutz; Kiess, Wieland; Siekmeyer, Manuela

    2016-06-01

    This article reports on a previously healthy 17-month-old boy who developed pulmonary mucormycosis after a near-drowning incident in a goose pond. The patient survived without neurological sequelae and recovered, under treatment with amphotericin B, from the rare and often invasive fungal infection with Rhizopus spp., usually occurring in immunodeficient patients.

  14. The production of corn kernel miso based on rice-koji fermented by Aspergillus oryzae and Rhizopus oligosporus

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    Diah Ratnaningrum

    2018-04-01

    Full Text Available The suitability of corn kernel as raw material to produce miso fermented by rice-koji containing Aspergillus oryzae and Rhizopus oligosporus has been investigated. The optimization was conducted on two important factors in miso production namely mold composition in rice-koji and salt concentration. The mold composition was prepared by inoculating the spores of 2% A. oryzae, 2% R. oligosporus, and 2% the mixture of both in a ratio of 1:1, 2:1, and 1:2 (v/v into different rice media. The mold composition was optimized to produce rice-koji with high α-amylase and protease activity. Different NaCl concentrations of 10%, 15%, and 20% were subjected to optimization process and added to each mixture after five days of fermentation. The salt concentration was also optimized to produce corn kernel miso with high glucose and high dissolved protein concentration. The result showed that rice-koji containing A. oryzae and R. oligosporus in the ratio of 1:1 had the highest α-amylase and protease activity of 0.42 U/mL and 0.45 U/mL respectively. In addition, the presence of 10% NaCl in corn kernel miso fermented by A. oryzae and R. oligosporus in the ratio of 1:1 exhibited the highest glucose and dissolved protein concentration of 0.64 mg/mL and 8.80 mg/mL respectively. The optimized corn kernel miso by A. oryzae and R. oligosporus in the ratio of 1:1 with 10% NaCl was subjected to nutrient content analysis and compared to the result before the corn kernel was fermented. The nutrient content analysis showed nutrient enhancement after corn kernel was fermented and transformed into a miso. Glucose, dissolved protein, and fat content increased 6.74, 1.34, 7.63 times respectively. This study concludes corn kernel could be utilized to produce a novel corn kernel miso for dietary diversification and for improving nutritional and health status.

  15. Effect of Inoculum Dosage Aspergillus niger and Rhizopus oryzae mixture with Fermentation Time of Oil Seed Cake (Jatropha curcas L) to the content of Protein and Crude Fiber

    Science.gov (United States)

    Kurniati, T.; Nurlaila, L.; Iim

    2017-04-01

    Jatropha curcas L already widely cultivated for its seeds pressed oil used as an alternative fuel. This plant productivity per hectare obtained 2.5-5 tonnes of oil/ha / year and jatropha seed cake from 5.5 to 9.5 tonnes/ha/year, nutrient content of Jatropha curcas seed L potential to be used as feed material, However, the constraints faced was the low crude protein and high crude protein. The purpose of the research was to determine the dosage of inoculum and fermentation time of Jatropha seed cake by a mixture of Aspergillus niger and Rhizopus oryzae on crude protein and crude fibre. The study was conducted by an experimental method using a Completely Randomised Design (CRD) factorial design (3×3). The treatment consisted of a mixture of three dosage levels of Aspergillus niger and Rhizopus oryzae (= 0.2% d1, d2 and d3 = 0.3% = 0.4%) and three levels of fermentation time (w1 = 72 hours, 96 hours and w2 = w3 = 120 hours) each repeated three times. The parameters measured were crude protein and crude fibre. The results showed that dosages of 0.3% (Aspergillus niger Rhizopus oryzae 0.15% and 0.15%) and 72 hours (d2w1) is the dosage and the optimal time to generate the highest crude protein content of 21.11% and crude fibre amounted to 21.36%.

  16. Purification and characterization of an extracellular lipase from a thermophilic Rhizopus oryzae strain isolated from palm fruit.

    Science.gov (United States)

    Hiol; Jonzo; Rugani; Druet; Sarda; Comeau

    2000-03-01

    We have isolated a lipolytic strain from palm fruit that was identified as a Rhizopus oryzae. Culture conditions were optimized and highest lipase production amounting to 120 U/ml was achieved after 4 days of cultivation. The extracellular lipase was purified 1200-fold by ammonium sulfate precipitation, sulphopropyl-Sepharose chromatography, Sephadex G 75 gel filtration and a second sulphopropyl-Sepharose chromatography. The specific activity of the purified enzyme was 8800 U/mg. The lipolytic enzyme has a molecular mass of 32 kDa by SDS-polyacrylamide gel electrophoresis and gel filtration. The enzyme exhibited a single band in active polyacrylamide gel electrophoresis and its isoelectric point was 7.6. Analysis of Rhizopus oryzae lipase by RP-HPLC confirmed the homogeneity of the enzyme preparation. Determination of the N-terminal sequence over 19 amino acid residues showed a high homology with lipases of the same genus. The optimum pH for enzyme activity was 7.5. Lipase was stable in the pH range from 4.5 to 7.5. The optimum temperature for lipase activity was 35 degrees C and about 65% of its activity was retained after incubation at 45 degrees C for 30 min. The lipolytic enzyme was inhibited by Triton X100, SDS, and metal ions such as Fe(3+), Cu(2+), Hg(2+) and Fe(2+). Lipase activity against triolein was enhanced by sodium cholate or taurocholate. The purified lipase had a preference for the hydrolysis of saturated fatty acid chains (C(8)-C(18)) and a 1, 3-position specificity. It showed a good stability in organic solvents and especially in long chain-fatty alcohol. The enzyme poorly hydrolyzed triacylglycerols containing n-3 polyunsaturated fatty acids, and appeared as a suitable biocatalyst for selective esterification of sardine free fatty acids with hexanol as substrate. About 76% of sardine free fatty acids were esterified after 30 h reaction whereas 90% of docosahexaenoic acid (DHA) was recovered in the unesterified fatty acids.

  17. Biosorption of Cr(VI) in Aqueous Solution using Microorganisms: Comparison of the Use of Rhizopus oryzae, Bacillus firmus, and Trichoderma viride

    Science.gov (United States)

    Safitri, Anna; Mahardini, Putri; Prasetyawan, Sasangka; Roosdiana, Anna

    2018-01-01

    In this work, the study of biosorption of Cr(VI) from aqueous solution was conducted using Rhizopus oryzae, Bacillus firmus, and Trichoderma viride as microorganisms that can absorb Cr(VI). The research is focused on determination of optimum conditions including pH, the number of R. oryzae, B. firmus, and T. viride (inoculums), and initial concentrations of Cr(VI) used. Optimum pH was obtained at pH 5, 4.5 and 6, for biosorption of Cr(VI) with R. oryzae, B. firmus, and T. viride, respectively, in the capacity of 45.3%, 24.5%, and 90.3%. The highest amount of Cr(VI) adsorbed for biosorption with R. oryzae, B. firmus, and T. viride, were 55.4%, 18.5%, and 74.5%, respectively, using 6-mL inoculums. The equilibrium concentrations achieved for R. oryzae, B. firmus, and T. viride were 60 mg/mL, 40 mg/mL, and 40 mg/mL, with the amount of Cr(VI) adsorbed were 32.4%, 28.2%, and 89.3%, respectively. The adsorption capacity for R. oryzae, B. firmus, and T. viride were 45.3 mg/1×106 colonies, 36.2 mg/1×106 cells, and 77.8 mg/1×106 colonies, respectively. Overall, the biosorbents effectivity order in the biosorption process of Cr(VI) are T. viride > R. oryzae > B. firmus.

  18. Carbohydrate-active enzymes from the zygomycete fungus Rhizopus oryzae: a highly specialized approach to carbohydrate degradation depicted at genome level

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    Henrissat Bernard

    2011-01-01

    Full Text Available Abstract Background Rhizopus oryzae is a zygomycete filamentous fungus, well-known as a saprobe ubiquitous in soil and as a pathogenic/spoilage fungus, causing Rhizopus rot and mucomycoses. Results Carbohydrate Active enzyme (CAZy annotation of the R. oryzae identified, in contrast to other filamentous fungi, a low number of glycoside hydrolases (GHs and a high number of glycosyl transferases (GTs and carbohydrate esterases (CEs. A detailed analysis of CAZy families, supported by growth data, demonstrates highly specialized plant and fungal cell wall degrading abilities distinct from ascomycetes and basidiomycetes. The specific genomic and growth features for degradation of easily digestible plant cell wall mono- and polysaccharides (starch, galactomannan, unbranched pectin, hexose sugars, chitin, chitosan, β-1,3-glucan and fungal cell wall fractions suggest specific adaptations of R. oryzae to its environment. Conclusions CAZy analyses of the genome of the zygomycete fungus R. oryzae and comparison to ascomycetes and basidiomycete species revealed how evolution has shaped its genetic content with respect to carbohydrate degradation, after divergence from the Ascomycota and Basidiomycota.

  19. High-Level Expression of Pro-Form Lipase from Rhizopus oryzae in Pichia pastoris and Its Purification and Characterization

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    Jian-Rong Wang

    2013-12-01

    Full Text Available A gene encoding Rhizopus oryzae lipase containing prosequence (ProROL was cloned into the pPICZαA and electrotransformed into the Pichia pastoris X-33 strain. The lipase was functionally expressed and secreted in Pichia pastoris with a molecular weight of 35 kDa. The maximum lipase activity of recombinant lipase (rProROL was 21,000 U/mL, which was obtained in a fed-batch cultivation after 168 h induction with methanol in a 50-L bioreactor. After fermentation, the supernatant was concentrated by ultrafiltration with a 10 kDa cut off membrane and purified with ion exchange chromatography using SP Sepharose Fast Flow chromatography. The optimum pH and temperature of the rProROL were pH 9.0 and 40 °C, respectively. The lipase was stable from pH 4.0 to 9.0 and from 25 to 55 °C. The enzyme activity was enhanced by Ca2+ and inhibited by Hg2+ and Ag+. The lipase showed high activity toward triglyceride-Tripalmitin (C16:0 and triglyceride-Trilaurin (C12:0.

  20. Immobilized Rhizopus oryzae lipase catalyzed synthesis of palm stearin and cetyl alcohol wax esters: Optimization by Response Surface Methodology

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    Gargouri Youssef

    2011-06-01

    Full Text Available Abstract Background Waxes are esters of long-chain fatty acids and long-chain alcohols. Their principal natural sources are animals (sperm whale oil and vegetables (jojoba which are expensive and not easily available. Wax esters synthesized by enzymatic transesterification, using palm stearin as raw material, can be considered as an alternative to natural ones. Results Palm stearin is a solid fraction obtained by fractionation of palm oil. Palm stearin was esterified with cetyl alcohol to produce a mixture of wax esters. A non-commercial immobilized lipase from Rhizopus oryzae was used as biocatalyst. Response surface methodology was employed to determine the effects of the temperature (30-50°C, the enzyme concentration (33.34-300 IU/mL, the alcohol/palm stearin molar ratio (3-7 mol/mol and the substrate concentration (0.06-0.34 g/mL on the conversion yield of palm stearin. Under optimal conditions (temperature, 30°C; enzyme concentration, 300 IU/mL; molar ratio 3 and substrate concentration 0.21 g/mL a high conversion yield of 98.52% was reached within a reaction time of 2 h. Conclusions Response surface methodology was successfully applied to determine the optimum operational conditions for synthesis of palm stearin based wax esters. This study may provide useful tools to develop economical and efficient processes for the synthesis of wax esters.

  1. One-pot conjugated linoleic acid production from castor oil by Rhizopus oryzae lipase and resting cells of Lactobacillus plantarum.

    Science.gov (United States)

    Khaskheli, Abid Ali; Talpur, Farah Naz; Cebeci Aydin, Aysun; Jawaid, Sana; Surhio, Muhammad Ali; Afridi, Hassan Imran

    2017-10-01

    Conjugated linoleic acid (CLA) has attracted as novel type of fatty acids having unusual health-promoting properties such as anticarcinogenic and antiobesitic effects. The present work employed castor oil as substrate for one-pot production of CLA using washed cells of Lactobacillus plantarum (L. plantarum) and lipases as catalysts. Among the screened lipases, the lipase Rhizopus oryzae (ROL) greatly assisted resting cells to produce CLA. Mass spectral analysis of the product showed that two major isomers of CLA were produced in the reaction mixture i.e. cis-9, trans-11 56.55% and trans-10, cis-12 43.45%. Optimum factors for CLA synthesis were found as substrate concentration (8 mg/mL), pH (6.5), washed cell concentration (12% w/v), and incubation time of 20 h. Hence, the combination of ROL with L. plantarum offers one pot production of CLA selectively using castor oil as a cost-effective substrate.

  2. The impact of Rhizopus oryzae cultivation on rice bran: Gamma-oryzanol recovery and its antioxidant properties.

    Science.gov (United States)

    Massarolo, Kelly Cristina; Denardi de Souza, Taiana; Collazzo, Carolina Carvalho; Badiale Furlong, Eliana; Souza Soares, Leonor Almeida de

    2017-08-01

    This study evaluated the effect of the solid state cultivation (SSC) time of rice bran by Rhizopus oryzae on γ-oryzanol recovery and its antioxidant properties. Gamma-oryzanol was extracted with organic solvents and its extracts were characterized by GC-FID and HPLC-UV. The antioxidant capacity was assessed by DPPH and ABTS + assays, β-carotene/linoleic acid system, and reduction of oxidation in lipid system. The biomass showed the γ-oryzanol recovery increased by 51.5% (20.52mg/g), and 5.7% in polyunsaturated fatty acids. The γ-oryzanol major components changing in their profile. The γ-oryzanol extract from biomass (72h) showed the greatest DPPH inhibition (59.0%), while 90.5% inhibition of oxidation of β-carotene/linoleic acid system, and 30% reduction of the indicators of oxidation in olive oil was observed in the one cultivated at 96h, these behaviors were confirmed by PCA analyses. SSC provides an increase in the γ-oryzanol recovery followed by improving of the functional properties of rice bran. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Optimization of lactic acid production by pellet-form Rhizopus oryzae in 3-L airlift bioreactor using response surface methodology.

    Science.gov (United States)

    Maneeboon, Thanapoom; Vanichsriratana, Wirat; Pomchaitaward, Chaiyaporn; Kitpreechavanich, Vichien

    2010-05-01

    The influence of two key environmental factors, pH and oxygen transfer coefficient (k(L)a), was evaluated on the lactic acid production as the main answer and, on the size of cell pellets of the fungal strain Rhizopus oryzae KPS106, as second dependant answer by response surface methodology using a central composite design. The results of the analysis of variance and modeling demonstrated that pH and k(L)a had a significant effect on lactic acid production by this strain. However, no interaction was observed between these two experimental factors. pH and k(L)a had no significant influence on the pellet size. Optimal pH and k(L)a of the fermentation medium for lactic acid production from response surface analysis was 5.85 and of 3.6 h(-1), respectively. The predicted and experimental lactic acid maximal values were 75.4 and 72.0 g/l, respectively, with pellets of an average of 2.54 +/- 0.41 mm. Five repeated batches in series were conducted with a mean lactic acid production of 77.54 g/l. The productivity was increased from 0.75 in the first batch to 0.99 g/l h in the last fifth batch.

  4. Transcriptional response of P. pastoris in fed-batch cultivations to Rhizopus oryzae lipase production reveals UPR induction

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    Valero Francisco

    2007-07-01

    Full Text Available Abstract Background The analysis of transcriptional levels of the genes involved in protein synthesis and secretion is a key factor to understand the host organism's responses to recombinant protein production, as well as their interaction with the cultivation conditions. Novel techniques such as the sandwich hybridization allow monitoring quantitatively the dynamic changes of specific RNAs. In this study, the transcriptional levels of some genes related to the unfolded protein response (UPR and central metabolism of Pichia pastoris were analysed during batch and fed-batch cultivations using an X-33-derived strain expressing a Rhizopus oryzae lipase under control of the formaldehyde dehydrogenase promoter (FLD1, namely the alcohol oxidase gene AOX1, the formaldehyde dehydrogenase FLD1, the protein disulfide isomerase PDI, the KAR2 gene coding for the BiP chaperone, the 26S rRNA and the R. oryzae lipase gene ROL. Results The transcriptional levels of the selected set of genes were first analysed in P. pastoris cells growing in shake flask cultures containing different carbon and nitrogen sources combinations, glycerol + ammonium, methanol + methylamine and sorbitol + methylamine. The transcriptional levels of the AOX1 and FLD1 genes were coherent with the known regulatory mechanism of C1 substrates in P. pastoris, whereas ROL induction lead to the up-regulation of KAR2 and PDI transcriptional levels, thus suggesting that ROL overexpression triggers the UPR. This was further confirmed in fed-batch cultivations performed at different growth rates. Transcriptional levels of the analysed set of genes were generally higher at higher growth rates. Nevertheless, when ROL was overexpressed in a strain having the UPR constitutively activated, significantly lower relative induction levels of these marker genes were detected. Conclusion The bead-based sandwich hybridization assay has shown its potential as a reliable instrument for quantification of

  5. Two unique ligand-binding clamps of Rhizopus oryzae starch binding domain for helical structure disruption of amylose.

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    Ting-Ying Jiang

    Full Text Available The N-terminal starch binding domain of Rhizopus oryzae glucoamylase (RoSBD has a high binding affinity for raw starch. RoSBD has two ligand-binding sites, each containing a ligand-binding clamp: a polyN clamp residing near binding site I is unique in that it is expressed in only three members of carbohydrate binding module family 21 (CBM21 members, and a Y32/F58 clamp located at binding site II is conserved in several CBMs. Here we characterized different roles of these sites in the binding of insoluble and soluble starches using an amylose-iodine complex assay, atomic force microscopy, isothermal titration calorimetry, site-directed mutagenesis, and structural bioinformatics. RoSBD induced the release of iodine from the amylose helical cavity and disrupted the helical structure of amylose type III, thereby significantly diminishing the thickness and length of the amylose type III fibrils. A point mutation in the critical ligand-binding residues of sites I and II, however, reduced both the binding affinity and amylose helix disruption. This is the first molecular model for structure disruption of the amylose helix by a non-hydrolytic CBM21 member. RoSBD apparently twists the helical amylose strands apart to expose more ligand surface for further SBD binding. Repeating the process triggers the relaxation and unwinding of amylose helices to generate thinner and shorter amylose fibrils, which are more susceptible to hydrolysis by glucoamylase. This model aids in understanding the natural roles of CBMs in protein-glycan interactions and contributes to potential molecular engineering of CBMs.

  6. Study of energetic-particle-irradiation induced biological effect on Rhizopus oryzae through synchrotron-FTIR micro-spectroscopy

    Science.gov (United States)

    Liu, Jinghua; Qi, Zeming; Huang, Qing; Wei, Xiaoli; Ke, Zhigang; Fang, Yusheng; Tian, Yangchao; Yu, Zengliang

    2013-01-01

    Energetic particles exist ubiquitously and cause varied biological effects such as DNA strand breaks, lipid peroxidation, protein modification, cell apoptosis or death. An emerging biotechnology based on ion-beam technique has been developed to serve as an effective tool for mutation breeding of crops and microbes. In order to improve the effectiveness of ion-beam biotechnology for mutation breeding, it is indispensible to gain a better understanding of the mechanism of the interactions between the energetic ions and biological systems which is still elusive. A new trend is to conduct more comprehensive research which is based on micro-scaled observation of the changes of the cellular structures and compositions under the interactions. For this purpose, advanced synchrotron FTIR (s-FTIR) microscopy was employed to monitor the cellular changes of single fungal hyphae under irradiation of α-particles from 241Am. Intracellular contents of ROS, MDA, GSSG/GSH and activities of CAT and SOD were measured via biochemical assay. Ion-irradiation on Rhizopus oryzae causes localized vacuolation, autolysis of cell wall and membrane, lipid peroxidation, DNA damage and conformational changes of proteins, which have been clearly revealed by the s-FTIR microspectroscopy. The different changes of cell viability, SOD and CAT activities can be explained by the ROS-involved chemical reactions. Evidently, the elevated level of ROS in hyphal cells upon irradiation plays the key role in the caused biological effect. This study demonstrates that s-FTIR microspectroscopy is an effective tool to study the damage of fungal hyphae caused by ionizing radiation and it facilitates the exploit of the mechanism for the interactions between the energetic ions and biological systems.

  7. Estudio de la producción heteróloga de una lipasa del hongo Rhizopus oryzae en la levadura metilotrófica Pichia pastoris

    OpenAIRE

    Serrano González, Alicia

    2004-01-01

    Consultable des del TDX Títol obtingut de la portada digitalitzada El trabajo recoge los principales aspectos de la producción recombinante de una lipasa del hongo Rhizopus oryzae (ROL) expresada en la levadura Pichia pastoris. El sistema de expresión empleado está basado en la utilización del promotor de la alcohol oxidasa (PAOX1) de la levadura y, por lo tanto es dependiente de la utilización de metanol como substrato inductor. El trabajo recoge una serie de estudios de producción en ...

  8. Effect of dietary supplementation with Rhizopus oryzae or Chrysonilia crassa on growth performance, blood profile, intestinal microbial population, and carcass traits in broilers exposed to heat stress

    OpenAIRE

    S. Sugiharto; T. Yudiarti; I. Isroli; E. Widiastuti; F. D. Putra

    2017-01-01

    Dietary supplementation of additives has recently been part of strategies to deal with the detrimental effects of heat stress (HS) on the performance and carcass traits in broiler chicks. This study aimed to investigate the effect of dietary supplementation with the fungi Rhizopus oryzae or Chrysonilia crassa on growth, blood profile, intestinal microbial population and carcass traits in broiler chicks subjected to HS. R. oryzae and C. crassa are filamentous fungi isolated from...

  9. Pb(II) and Cd(II) removal from aqueous solution, shipyard wastewater, and landfill leachate by modified Rhizopus oryzae biomass

    Science.gov (United States)

    Naeimi, Behrouz; Foroutan, Rauf; Ahmadi, Bahram; Sadeghzadeh, Farzaneh; Ramavandi, Bahman

    2018-04-01

    This study was designed to remove Pb(II) and Cd(II) from aqueous solution, shipyard wastewater, and sanitary landfill leachate using an alkaline-modified Rhizopus oryzae biomass. According to the Fourier transform infrared test, different functional groups like O–H, N–H, C=O, and P–O were detected in the bioadsorbent. The x-ray fluorescence (XRF) analysis showed that CaO, P2O3, and SO3 oxides have the highest content in the bioadsorbent. The surface area of modified Rhizopus oryzae was obtained as 20.32 m2 g‑1. The effect of initial pH, temperature, contact time, and bioadsorbent dose on the metals removal was discussed. At optimal conditions, maximum Pb(II) and Cd(II) removal was obtained 95.66% and 94.55%, respectively. Freundlich model was well- accurately described the equilibrium data. Among four studied models, the pseudo-second-order was better able to describe the kinetic behavior of the bioadsorption process. The amount of enthalpy, free energy of Gibbs, and entropy parameters indicated that the bioadsorption process of studied heavy metals is negative, exothermic, and spontaneous. The amount of heavy metals in a shipyard wastewater and sanitary landfill leachate was significantly decreased by using the developed bioadsorbent.

  10. The influence of inoculum composition on selected bioactive and nutritional parameters of grass pea tempeh obtained by mixed-culture fermentation with Rhizopus oligosporus and Aspergillus oryzae strains.

    Science.gov (United States)

    Starzynska-Janiszewska, A; Stodolak, B; Dulinski, R; Mickowska, B

    2012-04-01

    Tempeh is a popular Indonesian product obtained from legume seeds by solid-state fermentation with Rhizopus sp. The aim of this research was to study the effect of simultaneous mixed-culture fermentation of grass pea seeds on selected parameters of products as compared to traditional tempeh. The inoculum contained different ratios of Rhizopus oligosporus and Aspergillus oryzae spores. The simultaneous fermentation of grass pea seeds with inoculum consisting of 1.2 × 10(6) R. oligosporus and 0.6 × 10(6) A. oryzae spores (per 60 g of seeds) resulted in a product of improved quality, as compared with traditionally made tempeh (obtained after inoculation with 1.2 × 10(6) R. oligosporus spores), at the same fermentation time. This product had radical scavenging ability 70% higher than the one obtained with pure R. oligosporus culture and contained 2.23 g/kg dm of soluble phenols. The thiamin and riboflavin levels were above three (340 µg/g dm) and two (50.50 µg/g dm) folds higher than in traditionally made tempeh, respectively. The product had 65% in vitro bioavailability of proteins and 33% in vitro bioavailability of sugars. It also contained 40% less 3-N-oxalyl-L-2, 3-diaminopropionic acid (0.074 g/kg dm), as compared to traditional tempeh.

  11. Stimulation with lysates of Aspergillus terreus, Candida krusei and Rhizopus oryzae maximizes cross-reactivity of anti-fungal T cells.

    Science.gov (United States)

    Deo, Shivashni S; Virassamy, Balaji; Halliday, Catriona; Clancy, Leighton; Chen, Sharon; Meyer, Wieland; Sorrell, Tania C; Gottlieb, David J

    2016-01-01

    Invasive fungal diseases caused by filamentous fungi and yeasts are significant causes of morbidity and mortality in immunosuppressed hematology patients. We previously published a method to expand Aspergillus fumigatus-specific T cells for clinical cell therapy. In the present study, we investigated expansion of T cells specific for other fungal pathogens and creation of a broadly reactive panfungal T-cell product. Fungal strains selected were those frequently observed in the clinical hematology setting and included Aspergillus, Candida, Fusarium, Rhizopus and Lomentospora/Scedosporium. Four T-cell cultures specific to each fungus were established. We selected lysates of Aspergillus terreus, Candida krusei and Rhizopus oryzae to expand panfungal T cells. Allelic restriction of anti-fungal activity was determined through the use of specific major histocompatibility complex class II-blocking antibodies. Individual T-cell cultures specific to each fungus could be expanded in vitro, generating predominantly CD4(+) T cells of which 8% to 20% were fungus-specific. We successfully expanded panfungal T cells from the peripheral blood (n = 8) and granulocyte-colony-stimulating factor-primed stem cell products (n = 3) of normal donors by using a combination of lysates from Aspergillus terreus, Candida krusei and Rhizopus oryzae. Anti-fungal activity was mediated through human leukocyte antigen (HLA)-DR alleles and was maintained when antigen-presenting cells from partially HLA-DRB1-matched donors were used to stimulate T cells. We demonstrate a method to manufacture panfungal T-cell products with specificity against a range of clinical fungal pathogens by use of the blood and stem cells of healthy donors as the starting material. The safety and efficacy of these products will need to be tested clinically. Copyright © 2015 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  12. Omics-based approaches reveal phospholipids remodeling of Rhizopus oryzae responding to furfural stress for fumaric acid-production from xylose.

    Science.gov (United States)

    Pan, Xinrong; Liu, Huanhuan; Liu, Jiao; Wang, Cheng; Wen, Jianping

    2016-12-01

    In order to relieve the toxicity of furfural on Rhizopus oryzae fermentation, the molecular mechanism of R. oryzae responding to furfural stress for fumaric acid-production was investigated by omics-based approaches. In metabolomics analysis, 29 metabolites including amino acid, sugars, polyols and fatty acids showed significant changes for maintaining the basic cell metabolism at the cost of lowering fumaric acid production. To further uncover the survival mechanism, lipidomics was carried out, revealing that phosphatidylcholine, phosphatidylglycerol, phosphatidylinositol and polyunsaturated acyl chains might be closely correlated with R. oryzae's adapting to furfural stress. Based on the above omics analysis, lecithin, inositol and soybean oil were exogenously supplemented separately with an optimized concentration in the presence of furfural, which increased fumaric acid titer from 5.78g/L to 10.03g/L, 10.05g/L and 12.13g/L (increased by 73.5%, 73.8% and 110%, respectively). These findings provide a methodological guidance for hemicellulose-fumaric acid development. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Fob1 and Fob2 proteins are virulence determinants of Rhizopus oryzae via facilitating iron uptake from ferrioxamine

    Science.gov (United States)

    Dialysis patients with chronic renal failure receiving deferoxamine for treating iron overload are uniquely predisposed for mucormycosis. Although not secreted by Mucorales, previous studies established that Rhizopus species utilize iron from ferrioxamine (iron-rich form of deferoxamine). Here we de...

  14. An optimized fed-batch culture strategy integrated with a one-step fermentation improves L-lactic acid production by Rhizopus oryzae.

    Science.gov (United States)

    Fu, Yongqian; Sun, Xiaolong; Zhu, Huayue; Jiang, Ru; Luo, Xi; Yin, Longfei

    2018-05-21

    In previous work, we proposed a novel modified one-step fermentation fed-batch strategy to efficiently generate L-lactic acid (L-LA) using Rhizopus oryzae. In this study, to further enhance efficiency of L-LA production through one-step fermentation in fed-batch cultures, we systematically investigated the initial peptone- and glucose-feeding approaches, including different initial peptone and glucose concentrations and maintained residual glucose levels. Based on the results of this study, culturing R. oryzae with initial peptone and glucose concentrations of 3.0 and 50.0 g/l, respectively, using a fed-batch strategy is an effective approach of producing L-LA through one-step fermentation. Changing the residual glucose had no obvious effect on the generation of L-LA. We determined the maximum LA production and productivity to be 162 g/l and 6.23 g/(l·h), respectively, during the acid production stage. Compared to our previous work, there was almost no change in L-LA production or yield; however, the productivity of L-LA increased by 14.3%.

  15. Biocatalytic Behaviour of Immobilized Rhizopus oryzae Lipase in the 1,3-Selective Ethanolysis of Sunflower Oil to Obtain a Biofuel Similar to Biodiesel

    Directory of Open Access Journals (Sweden)

    Carlos Luna

    2014-08-01

    Full Text Available A new biofuel similar to biodiesel was obtained in the 1,3-selective transesterification reaction of sunflower oil with ethanol using as biocatalyst a Rhizopus oryzae lipase (ROL immobilized on Sepiolite, an inorganic support. The studied lipase was a low cost powdered enzyme preparation, Biolipase-R, from Biocon-Spain, a multipurpose additive used in food industry. In this respect, it is developed a study to optimize the immobilization procedure of these lipases on Sepiolite. Covalent immobilization was achieved by the development of an inorganic-organic hybrid linker formed by a functionalized hydrocarbon chain with a pendant benzaldehyde, bonded to the AlPO4 support surface. Thus, the covalent immobilization of lipases on amorphous AlPO4/sepiolite (20/80 wt % support was evaluated by using two different linkers (p-hydroxybenzaldehyde and benzylamine-terephthalic aldehyde, respectively. Besides, the catalytic behavior of lipases after physical adsorption on the demineralized sepiolite  was also evaluated. Obtained results indicated that covalent immobilization with the p-hydroxybenzaldehyde linker gave the best biocatalytic behavior. Thus, this covalently immobilized lipase showed a remarkable stability as well as an excellent capacity of reutilization (more than five successive reuses without a significant loss of its initial catalytic activity. This could allow a more efficient fabrication of biodiesel minimizing the glycerol waste production.

  16. Eco-friendly methodology for efficient synthesis and scale-up of 2-ethylhexyl-p-methoxycinnamate using Rhizopus oryzae lipase and its biological evaluation.

    Science.gov (United States)

    Kumar, Vinod; Jahan, Firdaus; Kameswaran, Karthikeya; Mahajan, Richi V; Saxena, Rajendra Kumar

    2014-06-01

    Lipase-mediated synthesis of phenolic acid esters is a green and economical alternative to current chemical methods. Octyl methoxycinnamate, an important UVB-absorbing compound, was synthesized by the esterification of p-methoxycinnamic acid with 2-ethyl hexanol using Rhizopus oryzae lipase. A molar ratio of 1:2 of p-methoxycinnamic acid and 2-ethyl hexanol was found to give an optimum yield using cyclo-octane (50 ml) as reaction solvent, at a temperature of 45 °C, and 750 U of lipase, resulting in a yield of 91.3 % in 96 h. This reaction was successfully scaled up to 400-ml reaction size where 88.6 %bioconversion was achieved. The synthesized compound was found to have superior antioxidant activity as compared to ascorbic acid. The synthesized compound also exhibited good antimicrobial activity against Escherichia coli, Klebsiella pneumonia, Salmonella typhi, Staphylococcus aures, Candida albicans (yeast), Aspergillus niger, Alternaria solani, and Fussarium oxysporum by well diffusion method in terms of zone of inhibitions (in mm).

  17. Antifungal effect of phenolic extract of fermented rice bran with Rhizopus oryzae and its potential use in loaf bread shelf life extension.

    Science.gov (United States)

    Denardi-Souza, Taiana; Luz, Carlos; Mañes, Jordi; Badiale-Furlong, Eliana; Meca, Giuseppe

    2018-03-30

    In this study the antifungal potential of a phenolic extract obtained from rice bran fermented with Rhizopus oryzae CECT 7560 and its application in the elaboration of bread was assessed. Eighteen compounds with antifungal potential were identified by LC-ESI-qTOF-MS in the extract: organic acids, gallates and gallotannins, flavonoids, ellagic acid and benzophenone derivatives. The extract was active against strains of Fusarium, Aspergillus and Penicillium, with minimum inhibitory concentration ranging from 390 to 3100 µg mL -1 and minimum fungicidal concentration variable from 780 to 6300 µg mL -1 . The strains that were most sensitive to the phenolic extract were F. graminearum, F. culmorum, F. poae, P. roqueforti, P. expansum and A. niger. The phenolic extract added at 5 and 1 g kg -1 concentrations in the preparation of bread loaves contaminated with P. expansum produced a reduction of 0.6 and 0.7 log CFU g -1 . The bread loaves treated with calcium propionate and 10 g kg -1 of the phenolic extract evidenced an improvement in their shelf lives of 3 days. The phenolic extract assessed in this study could be considered as an alternative for inhibiting toxigenic fungi and as a substitute for synthetic compounds in food preservation. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  18. Response surface optimization for the transesterification of karanja oil using immobilized whole cells of Rhizopus oryzae in n-hexane system

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, Devanesan; Rajendran, Aravindan; Thangavelu, Viruthagiri [Annamalai University, Department of Chemical Engineering, Faculty of Engineering and Technology, Biochemical Engineering Laboratory, Annamalai Nagar, Tamil Nadu (India)

    2012-03-15

    Non-edible oils represent one of the most viable alternative feed stocks for the production of large volumes of biodiesel at cheaper cost in tropical countries. The objective of the present study is to investigate the ability of the immobilized whole cells of Rhizopus oryzae MTCC 262 to catalyze the biodiesel production from karanja oil in n-hexane system. Response surface methodology was employed to evaluate the effects of synthesis parameters, such as molar ratio of oil to alcohol, reaction temperature and reaction time on percentage biodiesel (methyl esters) yield. Transesterification was performed in shake flasks containing immobilized cells in the reaction mixture with 10% oil weight of n-hexane. The quadratic effects of molar ratio of oil to alcohol and reaction time proved to be the significant at 1% and 5% levels, respectively. The optimum synthesis conditions were found to be: molar ratio of oil to alcohol 1:2.73, reaction temperature 41.39 C and reaction time 73.97 h. Biodiesel yield (methyl ester) was 75.98 (wt.%) under the optimal conditions and the subsequent verification experiments with biodiesel yield of 78.0 (wt.%) confirmed the validity of the proposed model. (orig.)

  19. Photosynthetic characterization of a rolled leaf mutant of rice ( Oryza ...

    African Journals Online (AJOL)

    A new rolling leaf rice mutant was identified which showed an apparently straighter longitudinal shape normal transverse rolling characters at all developing stages. The chlorophyll contents per fresh weight of this mutant leaves were lower than those of wild-type. The electron transfer rate (ETR) and photochemical ...

  20. Comparative analysis for the production of fatty acid alkyl esterase using whole cell biocatalyst and purified enzyme from Rhizopus oryzae on waste cooking oil (sunflower oil).

    Science.gov (United States)

    Balasubramaniam, Bharathiraja; Sudalaiyadum Perumal, Ayyappasamy; Jayaraman, Jayamuthunagai; Mani, Jayakumar; Ramanujam, Praveenkumar

    2012-08-01

    The petroleum fuel is nearing the line of extinction. Recent research and technology have provided promising outcomes to rely on biodiesel as the alternative and conventional source of fuel. The use of renewable source - vegetable oil constitutes the main stream of research. In this preliminary study, Waste Cooking Oil (WCO) was used as the substrate for biodiesel production. Lipase enzyme producing fungi Rhizopus oryzae 262 and commercially available pure lipase enzyme were used for comparative study in the production of Fatty Acid Alkyl Esters (FAAE). The whole cell (RO 262) and pure lipase enzyme (PE) were immobilized using calcium alginate beads. Calcium alginate was prepared by optimizing with different molar ratios of calcium chloride and different per cent sodium alginate. Entrapment immobilization was done for whole cell biocatalyst (WCB). PE was also immobilized by entrapment for the transesterification reaction. Seven different solvents - methanol, ethanol, n-propanol, n-butanol, iso-propanol, iso-butanol and iso-amyl alcohol were used as the acyl acceptors. The reaction parameters like temperature (30°C), molar ratio (1:3 - oil:solvent), reaction time (24 h), and amount of enzyme (10% mass ratio to oil) were also optimized for methanol alone. The same parameters were adopted for the other acyl acceptors too. Among the different acyl acceptors - methanol, whose reaction parameters were optimized showed maximum conversion of triglycerides to FAAE-94% with PE and 84% with WCB. On the whole, PE showed better catalytic converting ability with all the acyl acceptor compared to WCB. Gas chromatography analysis (GC) was done to determine the fatty acid composition of WCO (sunflower oil) and FAAE production with different acyl acceptors. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Genomic diversity among Basmati rice ( Oryza sativa L) mutants ...

    African Journals Online (AJOL)

    Mutation breeding can be considered successful in obtaining new cultivars and broadening the genetic base of rice crop. In order to obtain new varieties of rice with improved agronomic and grain characteristics, gamma radiation (60Co) has been used to generate novel mutants of the Basmati rice. In this study rice cultivars ...

  2. Effect of dietary supplementation with Rhizopus oryzae or Chrysonilia crassa on growth performance, blood profile, intestinal microbial population, and carcass traits in broilers exposed to heat stress

    Directory of Open Access Journals (Sweden)

    S. Sugiharto

    2017-09-01

    Full Text Available Dietary supplementation of additives has recently been part of strategies to deal with the detrimental effects of heat stress (HS on the performance and carcass traits in broiler chicks. This study aimed to investigate the effect of dietary supplementation with the fungi Rhizopus oryzae or Chrysonilia crassa on growth, blood profile, intestinal microbial population and carcass traits in broiler chicks subjected to HS. R. oryzae and C. crassa are filamentous fungi isolated from the ileum of indigenous Indonesian chickens which exhibited probiotic and antioxidant properties. Two hundred and forty 21-day-old male broiler chicks were randomly allotted into six groups, including birds reared under normal temperature (28 ± 2 °C (CONT, birds reared under HS conditions (35 ± 2 °C (HS-CONT, birds reared under HS and provided with commercial anti-stress formula (HS-VIT, birds reared under HS and provided with R. oryzae (HS-RO, birds reared under HS and provided with C. crassa (HS-CC and birds reared under HS and provided with rice bran (HS-RB. Body weight gain was highest (P < 0. 01 and lowest (P < 0. 01 in CONT and HS-CONT birds, respectively. The heart was heavier (P < 0. 05 in CONT than in HS-CONT and HS-VIT birds. CONT birds had heavier duodenum (P < 0. 05 and jejunum (P < 0. 01 than other birds. Eosinophils was higher (P < 0. 05 in HS-CC than in other birds. Low-density lipoprotein (LDL was higher (P < 0. 05 in HS-CONT than in CONT, HS-VIT and HS-CC birds. Total triglyceride was highest (P < 0. 05 and lowest (P < 0. 05 in HS-RB and HS-RO birds, respectively. Alanine aminotransferase (ALT was higher (P < 0. 05 in HS-CONT than in other HS birds. Total protein was lowest and highest (P < 0. 05 in CONT and HS-CONT birds, respectively. Albumin was higher (P < 0. 05 in HS-CONT and HS-VIT than in HS-RO birds. Globulin was lower (P < 0. 05 in CONT than in HS

  3. Analysis on the DNA Fingerprinting of Aspergillus Oryzae Mutant Induced by High Hydrostatic Pressure

    International Nuclear Information System (INIS)

    Wang Hua; Zhang Jian; Wang Kai; Liu Bing-Bing; Zou Bo; Zou Guang-Tian; Yang Fan; Shen Si-Le

    2011-01-01

    The mutant strains of aspergillus oryzae (HP300a) are screened under 300 MPa for 20 min. Compared with the control strains, the screened mutant strains have unique properties such as genetic stability, rapid growth, lots of spores, and high protease activity. Random amplified polymorphic DNA (RAPD) and inter simple sequence repeats (ISSR) are used to analyze the DNA fingerprinting of HP300a and the control strains. There are 67.9% and 51.3% polymorphic bands obtained by these two markers, respectively, indicating significant genetic variations between HP300a and the control strains. In addition, comparison of HP300a and the control strains, the genetic distances of random sequence and simple sequence repeat of DNA are 0.51 and 0.34, respectively. (general)

  4. Analysis on the DNA Fingerprinting of Aspergillus Oryzae Mutant Induced by High Hydrostatic Pressure

    Science.gov (United States)

    Wang, Hua; Zhang, Jian; Yang, Fan; Wang, Kai; Shen, Si-Le; Liu, Bing-Bing; Zou, Bo; Zou, Guang-Tian

    2011-01-01

    The mutant strains of aspergillus oryzae (HP300a) are screened under 300 MPa for 20 min. Compared with the control strains, the screened mutant strains have unique properties such as genetic stability, rapid growth, lots of spores, and high protease activity. Random amplified polymorphic DNA (RAPD) and inter simple sequence repeats (ISSR) are used to analyze the DNA fingerprinting of HP300a and the control strains. There are 67.9% and 51.3% polymorphic bands obtained by these two markers, respectively, indicating significant genetic variations between HP300a and the control strains. In addition, comparison of HP300a and the control strains, the genetic distances of random sequence and simple sequence repeat of DNA are 0.51 and 0.34, respectively.

  5. Screening for rice mutant of resistance to piricularia oryzae by irradiation and in vitro technique

    International Nuclear Information System (INIS)

    Wang Cailian; Xu Gang; Chen Qiufang; Jin Wei

    2001-01-01

    The ability of callus formation and green plant regeneration was very different for different rice types and varieties in mature embryo. LS-5 was optimum medium for mature embryo. Increase in plant regeneration capacity was found with 100, 150 Gy gamma rays. The differentiation and regeneration of green plants were obviously improved when the anthers on induction medium were with 30 Gy of gamma rays. The change of free amino acids in subcultured callus tissue in rice were investigated after callus were treated with cultured filtrate from Piricularia oryzae. Fourteen kinds of free amino acid could be quantitatively analysed, among which, contents of serine and glutamate were the highest and made up about 20% of total amino acids respectively. The total amino acids in callus tissue of resistant varieties before treated with cultured filtrate were higher than that of susceptible varieties. However the total amino acids were decreased in the resistant varieties and increased in the susceptible varieties after treatment with the filtrate. Arginine was found in the variety of Zhen Kong No. 13. Disease resistance of R 2 plants screened with toxin was increased. Five mutants with resistance to Piricularia oryzae were selected

  6. A comparative secretome analysis of industrial Aspergillus oryzae and its spontaneous mutant ZJGS-LZ-21.

    Science.gov (United States)

    Zhu, Yuanyuan; Liang, Xinle; Zhang, Hong; Feng, Wei; Liu, Ye; Zhang, Fuming; Linhardt, Robert J

    2017-05-02

    Aspergillus oryzae koji plays a crucial role in fermented food products due to the hydrolytic activities of secreted enzymes. In the present study, we performed a comparative secretome analysis of the industrial strain of Aspergillus oryzae 3.042 and its spontaneous mutantZJGS-LZ-21. One hundred and fifty two (152) differential protein spots were excised (p<0.05), and 25 proteins were identified. Of the identified proteins, 91.3% belonged to hydrolytic enzymes acting on carbohydrates or proteins. Consistent with their enzyme activities, the expression of 14 proteins involved in the degradation of cellulose, hemicellulose, starch and proteins, increased in the ZJGS-LZ-21isolate. In particular, increased levels of acid protease (Pep) may favor the degradation of soy proteins in acidic environments and promote the cleavage of allergenic soybean proteins in fermentation, resulting in improvements of product safety and quality. The ZJGS-LZ-21 isolate showed higher protein secretion and increased hydrolytic activities than did strain 3.042, indicating its promising application in soybean paste fermentation. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Induction of Aspergillus oryzae mutant strains producing increased levels of α-amylase by gamma-irradiation

    International Nuclear Information System (INIS)

    Ito, Hitoshi; Nessa, Azizun

    1996-01-01

    Spores of Aspergillus oryzae IAM 2630 were suspended in 0.067 m phosphate buffer and irradiated with gamma rays. Spores were incubated for 7 days and colony mutants counted by observing colour change compared to normal colours. α-amylase activities of the normal and mutant colonies were assayed. DNA assay of the spores was also carried out, after culture on different plating media. Enzyme production increased 2-5 times with increasing radiation dose. Increased spore size and DNA content was also observed in mutant strains with higher enzyme production suggesting that enzyme production is genetically controlled. Ultraviolet radiation did not appear to induce higher frequency of mutation. (UK)

  8. Induction of Aspergillus oryzae mutant strains producing increased levels of {alpha}-amylase by gamma-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hitoshi; Nessa, Azizun [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1996-12-01

    Spores of Aspergillus oryzae IAM 2630 were suspended in 0.067 m phosphate buffer and irradiated with gamma rays. Spores were incubated for 7 days and colony mutants counted by observing colour change compared to normal colours. {alpha}-amylase activities of the normal and mutant colonies were assayed. DNA assay of the spores was also carried out, after culture on different plating media. Enzyme production increased 2-5 times with increasing radiation dose. Increased spore size and DNA content was also observed in mutant strains with higher enzyme production suggesting that enzyme production is genetically controlled. Ultraviolet radiation did not appear to induce higher frequency of mutation. (UK).

  9. Biotransformation of L-tyrosine to Dopamine by a Calcium Alginate Immobilized Mutant Strain of Aspergillus oryzae.

    Science.gov (United States)

    Ali, Sikander; Nawaz, Wajeeha

    2016-08-01

    The present research work is concerned with the biotransformation of L-tyrosine to dopamine (DA) by calcium alginate entrapped conidiospores of a mutant strain of Aspergillus oryzae. Different strains of A. oryzae were isolated from soil. Out of 13 isolated strains, isolate-2 (I-2) was found to be a better DA producer. The wild-type I-2 was chemically improved by treating it with different concentrations of ethyl methyl sulfonate (EMS). Among seven mutant variants, EMS-6 exhibiting maximal DA activity of 43 μg/ml was selected. The strain was further exposed with L-cysteine HCl to make it resistant against diversion and environmental stress. The conidiospores of selected mutant variant A. oryzae EMS-6 strain were entrapped in calcium alginate beads. Different parameters for immobilization were investigated. The activity was further improved from 44 to 62 μg/ml under optimized conditions (1.5 % sodium alginate, 2 ml inoculum, and 2 mm bead size). The best resistant mutant variable exhibited over threefold increase in DA activity (62 μg/ml) than did wild-type I-2 (21 μg/ml) in the reaction mixture. From the results presented in the study, it was observed that high titers of DA activity in vitro could effectively be achieved by the EMS-induced mutagenesis of filamentous fungus culture used.

  10. IN VITRO BIOACTIVITY OF CREOSOTE BUSH EXTRACTS (LARREA TRIDENTATA ON THE INHIBITION OF POSTHARVEST FUNGI: PENICILLIUM POLONICUM, ASPERGILLUS NIGER, RHIZOPUS ORYZAE Y ALTERNARIA TENUISSIMA

    Directory of Open Access Journals (Sweden)

    O. Peñuelas-Rubio

    2015-11-01

    Full Text Available En el presente estudio se evaluó la eficiencia de extractos vegetales deLarrea tridentataobtenidos con diclorometano, etanol, metanol y agua, sobre el crecimiento radial in vitro de cuatro hongos fitopatógenos, los cuales primeramente fueron identificados en género y especie empleando claves taxonómicas y técnicas moleculares. Para los bioensayosin vitrose aplicaron diseños completamente al azar con cuatro tratamientos y tres repeticiones en cada hongo, utilizando las concentraciones: 0, 250, 500 y 750 ppm paraAlternaria sp.; 0, 2000, 2500 y 3000 paraAspergillus sp.; 0, 1500, 1750 y 2000 paraPenicillium sp. y 0, 150, 200 y 250 ppm paraRhizopus sp. Cada tratamiento tuvo tres repeticiones. El análisis molecular determinó la especie tenuissima paraAlternaria,nigerparaApergillus,polonicumparaPenicilliumyoryzaeparaRhizopus. En cuanto a las pruebasin vitro, se determinaron inhibiciones del 100% para tres de los hongos en estudio:Alternaria tenuissimacon extracto EtOH a 750 ppm;Aspergillus nigercon extracto DCM a 3000 ppm yRhizopus oryzaea partir de 150 ppm y 250 ppm de los extractos DCM y EtOH respectivamente. Se presentó una inhibición del 82% a 2000 ppm paraPenicillium polonicum. Se concluye que a pesar de las diferencias en susceptibilidad entre las especies fúngicas, los extractos deLarrea tridentataobtenidos con etanol y dicloromentano son efectivos para el control de los hongos fitopatógenos bajo estudioin vitro.

  11. A new and efficient approach for construction of uridine/uracil auxotrophic mutants in the filamentous fungus Aspergillus oryzae using Agrobacterium tumefaciens-mediated transformation.

    Science.gov (United States)

    Nguyen, Khuyen Thi; Ho, Quynh Ngoc; Do, Loc Thi Binh Xuan; Mai, Linh Thi Dam; Pham, Duc-Ngoc; Tran, Huyen Thi Thanh; Le, Diep Hong; Nguyen, Huy Quang; Tran, Van-Tuan

    2017-06-01

    Aspergillus oryzae is a filamentous fungus widely used in food industry and as a microbial cell factory for recombinant protein production. Due to the inherent resistance of A. oryzae to common antifungal compounds, genetic transformation of this mold usually requires auxotrophic mutants. In this study, we show that Agrobacterium tumefaciens-mediated transformation (ATMT) method is very efficient for deletion of the pyrG gene in different Aspergillus oryzae wild-type strains to generate uridine/uracil auxotrophic mutants. Our data indicated that all the obtained uridine/uracil auxotrophic transformants, which are 5- fluoroorotic acid (5-FOA) resistant, exist as the pyrG deletion mutants. Using these auxotrophic mutants and the pyrG selectable marker for genetic transformation via A. tumefaciens, we could get about 1060 transformants per 10 6 fungal spores. In addition, these A. oryzae mutants were also used successfully for expression of the DsRed fluorescent reporter gene under control of the A. oryzae amyB promoter by the ATMT method, which resulted in obvious red transformants on agar plates. Our work provides a new and effective approach for constructing the uridine/uracil auxotrophic mutants in the importantly industrial fungus A. oryzae. This strategy appears to be applicable to other filamentous fungi to develop similar genetic transformation systems based on auxotrophic/nutritional markers for food-grade recombinant applications.

  12. Maximization of Intracellular Lipase Production in a Lipase-Overproducing Mutant Derivative of Rhizopus oligosporus DGM 31: A Kinetic Study

    Directory of Open Access Journals (Sweden)

    Tehreema Iftikhar

    2008-01-01

    Full Text Available Regulation and maximization of lipase production in a mutant derivative of R. oligosporus has been investigated using different substrates, inoculum sizes, pH of the medium, temperature, and nitrogen sources in shake flask experiments and batch fermentation in a fermentor. The production of intracellular lipase was improved 3 times following medium optimization involving one-at-a-time approach and aeration in the fermentor. Interestingly, intracellular lipase was poorly induced by oils, instead its production was induced by sugars, mainly starch, lactose, sucrose, xylose, glucose and glycerol. Dependent variables studied were cell mass, lipase activity, lipase yield, lipase specific and volumetric rate of formation. It was confirmed that lipase production in the derepressed mutant is sufficiently uncoupled from catabolite repression. The results of average specific productivities at various temperatures worked out according to the Arrhenius equation revealed that mutation decreased the magnitude of enthalpy and entropy demand in the inactivation equilibrium during product formation, suggesting that mutation made the metabolic network of the organism thermally more stable. The highest magnitudes of volumetric productivity (QP=490 IU/(L·h and other product attributes of lipase formation occurring on optimized medium in the fermentor are greater than the values reported by other workers. The purified enzyme is monomeric in nature and exhibits stability up to 80 °C and pH=6.0–8.0. Activation energy, enthalpy and entropy of catalysis at 50 °C, and magnitudes of Gibbs free energy for substrate binding, transition state stabilization and melting point indicated that this lipase is highly thermostable.

  13. Construction of brewing-wine Aspergillus oryzae pyrG- mutant by pyrG gene deletion and its application in homology transformation.

    Science.gov (United States)

    Du, Yu; Xie, Guizhen; Yang, Chunfa; Fang, Baishan; Chen, Hongwen

    2014-06-01

    pyrG(-) host cells are indispensable for pyrG(-) based transformation system. Isolations of pyrG(-) host cells by random mutations are limited by time-consuming, unclear genetic background and potential interferences of homogenous recombination. The purpose of this study was to construct brewing-wine Aspergillus oryzae pyrG(-) mutant by site-directed mutation of pyrG gene deletion which would be used as a host for further transformation. pMD-pyrGAB, a vector carrying pyrG deletion cassette, was used to construct pyrG(-) mutant of A. oryzae. Three stable pyrG deletion mutants of A. oryzae were isolated by resistant to 5-fluoroorotic acid and confirmed by polymerase chain reaction analysis, indicating that pyrG was completely excised. The ΔpyrG mutants were applied as pyrG(-) host cells to disrupt xdh gene encoding xylitol dehydrogenase, which involves in xylitol production of A. oryzae. The xdh disruption mutants were efficiently constructed by transforming a pMD-pyrG-xdh disruption plasmid carrying pyrG, and the produced xylitol concentration of the Δxdh mutant was three times as much as that of the ΔpyrG recipient. Site-directed pyrG gene deletion is thus an effective way for the isolation of pyrG(-) host cells, and the established host-vector system could be applied in further functional genomics analysis and molecular breeding of A. oryzae. © The Author 2014. Published by ABBS Editorial Office in association with Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences.

  14. Primary study on lesion mimic mutants of rice (oryza sativa L.)

    International Nuclear Information System (INIS)

    Hao Zhongna; Zhang Hongzhi; Tao Rongixang

    2007-01-01

    Nineteen lesion mimic mutants (xsl1-19) of japonica rice Xiushui11 were obtained by γ-rays irradiation treatment. All mutants belonged to whole life lesion mimic. Lesion mimic of mutants didn't largen after tillering stage, leaves didn't wither, and no effect on the plants exsert spikes and seed. When the highest temperature in day exceeded 32 degree C in seedling stage, lesion mimic of all mutant expect xsl19 disappeared. Under 32 degree C, lesion mimic would appear gradually, and symptoms weren't inhibited by high temperature after 5 leaf stage. The plant heights of all lesion mimic mutants were 47.56-63.54 cm in the tillering stage, and that of CK was 83.75 cm; but the dwarf phenomenon of mutants only appeared before tillering stage, and didn't affect plant heights finally; the heading dates of mutants were the same to the CK, the ear length of all mutants were 9.43-15.19 cm, and that of CK was 16.41 cm; the total grain quantity per spike of all mutants were 88.17-165.33, and those of xsl19 and CK were 49.50 and 76.17. The results showed all lesion mimic mutants except xsl19 had short spikes and total grain quantity per spike increasing. All lesion mimic mutants were susceptible to Magnaporthe grisea, and they had no relationship with resistance. (authors)

  15. Optimisation of nutritional requirements for dopamine synthesis by calcium alginate-entrapped mutant strain of Aspergillus oryzae EMS-6.

    Science.gov (United States)

    Ali, Sikander; Nawaz, Wajeeha

    2017-02-01

    The optimisation of nutritional requirements for dopamine (DA) synthesis by calcium alginate-entrapped mutant variant of Aspergillus oryzae EMS-6 using submerged fermentation technique was investigated. A total of 13 strains were isolated from soil. Isolate I-2 was selected as a better producer of DA and improved by exposing with ethyl methylsulphonate (EMS). EMS-6 was selected as it exhibited 43 μg/mL DA activity. The mutant variable was further treated with low levels of l-cysteine HCl to make it resistant against diversion and environmental stress. The conidiospores of mutant variant were entrapped in calcium alginate beads for stable product formation. EMS-6 gave maximum DA activity (124 μg/mL) when supplemented with 0.1% peptone and 0.2% sucrose, under optimised parameters viz. pH 3, temperature of 55 °C and incubation time of 70 min. The study involves the high profile of DA activity and is needed, as DA is capable to control numerous neurogenic disorders.

  16. Enhanced accumulation of U(VI) by Aspergillus oryzae mutant generated by dielectric barrier discharge air plasma

    International Nuclear Information System (INIS)

    Wencheng Song; North China Electric Power University, Beijing; Xiangxue Wang; Soochow University, Suzhou; Wen Tao; Hongqing Wang; Tasawar Hayat; Quaid-I-Azam University, Islamabad; Xiangke Wang; Soochow University, Suzhou; King Abdulaziz University, Jeddah

    2016-01-01

    Aspergillus oryzae was isolated from radionuclides' contaminated soils, and dielectric barrier discharge plasma was used to mutate A. oryzae to improve bioremediation capability of U(VI) pollution. The maximum accumulation capacities of U(VI) on mutated A.oryzae was 627.4 mg/g at T = 298 K and pH = 5.5, which was approximately twice than that of raw A.oryzae. XPS analysis indicated that U(VI) accumulation on mutated A. oryzae was largely attributable to nitrogen- and oxygen-containing functional groups on fungal mycelia. The mutated A. oryzae can be harnessed as bioremediation agents for radionuclides pollution. (author)

  17. The adaptability of upland rice waxy mutant (Oryza sativa L.) to marginal land in Batumarta

    International Nuclear Information System (INIS)

    Dwimahyani, Ita; Mitrosuhardjo, M.M.

    1998-01-01

    A field experiment had been conducted at Batumarta, Lampung Province to test the adaptability of upland rice waxy mutant (DT 20.11.84) at marginal land. Similar experiments had also been conducted in fertilize soil at Ps. Jumat, Jakarta and Citayam, Kabupaten Bogor. Agronomic evaluation such as number of tiller, panicle length number of seeds per tiller, and weight of 1000 grains from waxy mutant line, which were cultivated at Batumarta showed adaptability was better than the original variety (Danau Tempe). Grains yield of waxy mutant line per ha at marginal land (Batubara) was higher than Danau Tempe i.e 2,34 and 1,89 ton/ha respectively. In addition to grain yield of waxy mutant line at Psr Jumat, Jakarta and Citayam, Bogor was lower than Danau Tempe. The Low of grain yield that waxy mutant compared with the original variety line was caused by number of tiller and panicle length of waxy mutant line also low. Results of experiment can be concluded that waxy mutant line was favourable growing at marginal land when compared with the original variety. (author)

  18. Promissory rice mutants (Oryza sativa L.) obtained by Gamma Rays induction in Peru

    International Nuclear Information System (INIS)

    Heros, E.; Gomez, L.

    2015-01-01

    To improve the available rice cultivars in Peru under irrigated conditions, it was tried the rice seed Amazonas and Capirona, cultivars adapted to irrigated conditions in highland jungle, both characterized for late maturity (140-150 days). The doses were: 150-250-350 Gy that induced mutants with different characteristics to the original cultivar like: early maturity, shorter, high yield and milling quality. In Amazonas cultivar were selected 72 mutants of the M 2 generation with agronomy value and continue in evaluation only the mutant (M35-20). There were applied the same doses of gamma rays with the cultivar Capirona, there is much radiosensitivity at high doses, they were selected two early mutants (MC 35-21 and MC 35-123-3) with an early life cycle days (15 days) than parental cultivar. Two mutants tolerant to salinity (12 dSm). Six mutants are still under evaluation, two of them (MC 25-23-1 and MC 35-45-4) have better yields with performances of 9.1 t ha -1 versus 6.6 t ha -1 . These mutants show lodging and shattering resistance. (Author)

  19. Inheritance and gene expression of a root-growth inhibiting mutant in rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    Kitano, H.; Futsuhara, Y.

    1990-01-01

    Full text: A root-growth inhibiting mutant was induced in the dwarf mutant line, 'Fukei 71', through ethylene-imine. The mutant is characterised by the excessive inhibition of both seminal and crown roots elongation just after germination, although its shoots grow nearly normal. To study the genetics, the mutant was crossed with its original line 'Fukei 71' and some other normal cultivars. Results show that the root-growth inhibition is controlled by a recessive gene (rt), independent of the dwarf gene, d-50(t) locus in Fukei 71. For elucidating the gene action on root morphogenesis, histological and cytological experiments were carried out using a longitudinal and transverse thin section of seminal and/or crown root tips. Observations suggest that the rt gene affects the normal formation of the epidermal system which is differentiated from the protoderm of the root apical meristem. (author)

  20. Identification of dominant male sterile mutants in rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    Zhu Xudong; Rutger, J.N.

    2000-01-01

    Genetic male sterile mutants 1783 and 1789 were selected from US variety Orion and Kaybonnet seeds treated by gamma irradiation. Investigation of fertility characterization of pollen and spikelets of these mutants were made by progeny tests in 1783 M 7 and 1789 M 6 generations. The results showed that genetic male sterile mutants 1783 and 1789 with the fertility segregating of 1 sterile: 1 fertile were controlled by a single dominant gene. The pollen staining of mutants characterized partial sterility. Open-pollinated seed set was about 30% and bagged seed set was only 0.3%-3.5%. It is concluded that dominant genetic male sterile is a useful tool in improvement of population for rice breeding

  1. Evaluation and genetic analysis of semi-dwarf mutants in rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    Awan, M.A.; Cheema, A.A.; Tahir, G.R.

    1984-01-01

    Four semi-dwarf mutants namely DM16-5-1, DM16-5-2, DM-2 and DM107-4 were derived from the local tall basmati cultivar. The mode of reduction of internode length was studied in DM107-4. The reduction in culm length was due to a corresponding but disproportionate reduction in all the internodes. It was inferred that reduction in internode length contributes more towards reduction in height as compared to the reduction in the total number of internodes. The effect of semi-dwarfism on some yield components (panicle characters) was studied in two semi-dwarf mutants viz. DM16-5-1 and DM107-4 compared to Basmati 370. A marginal reduction in the panicle axis, primary branches per panicle, secondary branches per primary branch per panicle, spikelets borne on secondary branches and total number of spikelets per panicle was observed in DM16-5-1, whereas, a significant reduction of these characters was observed in DM107-4. Evaluation of the semi-dwarf mutants with respect to grain yield and harvest index showed that all the mutants possess high yield potential with higher harvest index values compared to the parent cultivar. Genetic analysis for plant height in 4x4 diallel involving semi-dwarf mutants revealed that mutant DM107-4 carries mainly recessive alleles while mutant DM16-5-1 showed some dominance effects as assessed through the estimates of genetic components of variation and Vr,Wr graph analysis. The semi-dwarf mutants have good potential for use as parents in cross-breeding programmes. (author)

  2. Isolation of a novel mutant gene for soil-surface rooting in rice (Oryza sativa L.).

    Science.gov (United States)

    Hanzawa, Eiko; Sasaki, Kazuhiro; Nagai, Shinsei; Obara, Mitsuhiro; Fukuta, Yoshimichi; Uga, Yusaku; Miyao, Akio; Hirochika, Hirohiko; Higashitani, Atsushi; Maekawa, Masahiko; Sato, Tadashi

    2013-11-20

    Root system architecture is an important trait affecting the uptake of nutrients and water by crops. Shallower root systems preferentially take up nutrients from the topsoil and help avoid unfavorable environments in deeper soil layers. We have found a soil-surface rooting mutant from an M2 population that was regenerated from seed calli of a japonica rice cultivar, Nipponbare. In this study, we examined the genetic and physiological characteristics of this mutant. The primary roots of the mutant showed no gravitropic response from the seedling stage on, whereas the gravitropic response of the shoots was normal. Segregation analyses by using an F2 population derived from a cross between the soil-surface rooting mutant and wild-type Nipponbare indicated that the trait was controlled by a single recessive gene, designated as sor1. Fine mapping by using an F2 population derived from a cross between the mutant and an indica rice cultivar, Kasalath, revealed that sor1 was located within a 136-kb region between the simple sequence repeat markers RM16254 and 2935-6 on the terminal region of the short arm of chromosome 4, where 13 putative open reading frames (ORFs) were found. We sequenced these ORFs and detected a 33-bp deletion in one of them, Os04g0101800. Transgenic plants of the mutant transformed with the genomic fragment carrying the Os04g0101800 sequence from Nipponbare showed normal gravitropic responses and no soil-surface rooting. These results suggest that sor1, a rice mutant causing soil-surface rooting and altered root gravitropic response, is allelic to Os04g0101800, and that a 33-bp deletion in the coding region of this gene causes the mutant phenotypes.

  3. Identification and quantification of flavonoids in yellow grain mutant of rice (Oryza sativa L.).

    Science.gov (United States)

    Kim, Backki; Woo, Sunmin; Kim, Mi-Jung; Kwon, Soon-Wook; Lee, Joohyun; Sung, Sang Hyun; Koh, Hee-Jong

    2018-02-15

    Flavonoids are naturally occurring phenolic compounds with potential health-promoting activities. Although anthocyanins and phenolic acids in coloured rice have been investigated, few studies have focused on flavonoids. Herein, we analysed flavonoids in a yellow grain rice mutant using UHPLC-DAD-ESI-Q-TOF-MS, and identified 19 flavonoids by comparing retention times and accurate mass measurements. Among them, six flavonoids, isoorientin, isoorientin 2″-O-glucoside, vitexin 2″-O-glucoside, isovitexin, isoscoparin 2″-O-glucoside and isoscoparin, were isolated and fully identified from the yellow grain rice mutant, and the levels were significantly higher than wild-type, with isoorientin particularly abundant in mutant embryo. Significant differences in total phenolic compounds and antioxidant activity were observed in mutant rice by DPPH, FRAP and TEAC assays. The results suggest that the representative six flavonoids may play an important role in colouration and antioxidant activity of embryo and endosperm tissue. The findings provide insight into flavonoid biosynthesis and the possibility of improving functionality in rice. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Breeding L(+)-lactic acid high productive mutant from xylose by nitrogen ions

    International Nuclear Information System (INIS)

    Yang Yingge; Li Wen; Liu Dan; Fan Yonghong; Wang Dongmei; Zheng Zhiming; Yu Zengliang

    2007-01-01

    In order to obtain higher L(+)-lactic acid yield strain fermentating from xylose, the original strain Rhizopus oryzae RLC41-6 was mutated by 10keV N + ion implantation. A mutant strain RQ4012 was obtained. After 72h shake-flask cultivation, the concentration of L(+)-lactic acid reached 74.37g/L, and the productivity was 1.03g/(L.h). Its lactic acid yield was 160% higher than that of the original one, and the mutant strain has high genetic stability. (authors)

  5. Analysis of a brittle-culm mutant of rice (Oryza sativa) induced bay gamma rays

    International Nuclear Information System (INIS)

    Doat, Jacqueline; Marie, R.

    1977-01-01

    An unexpected ''brittle-culm'' mutant has been screened in the progeny of the rice cultivar ''Balilla 28'' after a seed treatment by gamma rays from a Cobalt-60 source. This property proved hereditable and true-breeding. It does not affect the high resistance to lodging of rice plants. Important difference were pointed out between control and mutant lines in cellulose content and 1 p. cent NaOH extracts: ''brittle-culm'' straw contains less cellulose and shows a degradation of glucid coupounds. The brittleness of plant tissues appears to be correlated with a partial depolymerization of cellulose, associated with a possible transformation from alpha- to beta- or gamma-cellulose [fr

  6. Non-linked inhibitory gene controls a disease mimicking mutant in rice [Oryza sativa L.

    International Nuclear Information System (INIS)

    Jambhulkar, S.J.; Joshua, D.C.; Goswamy, D.G.

    2001-01-01

    A gamma ray induced disease mimicking mutant called luchai lesion was isolated in the rice variety White Luchai 112. The appearance of small light red lesions and their development continued from seedling to flowering. The lesions appeared gradually on older leaves and their uncontrolled spread eventually lead to leaf senescence. They resembled the disease spots caused by Magnaporthe grisea. However, pathological studies ruled out the possibility of pathogen mediated disease symptoms. Genetic studies revealed that lesions were governed by a dominant gene; however, their expression was suppressed in presence of a non-linked inhibitory gene. It is hypothesised that the plant cells of the mutant are able to sense inbuilt spontaneous signals leading to lesion development, but in presence of an inhibitory gene the signals are suppressed by perturbation in the signal transduction pathway [it

  7. Agronomic and molecular evaluation of induced mutant rice (oryza sativa l.) lines in Egypt

    International Nuclear Information System (INIS)

    Sshehzad, T.; Allah, A.; Aallah, E.A.; Ammar, M.H.; Abdelkhalik, A.H.

    2011-01-01

    The present study was conducted at the farm of the Rice Research and Training Center, Sakha, Kafr El-Sheikh, Egypt, during 2000-2007 rice sowing seasons. Five rice varieties viz., Giza 171, Giza 175, Giza 176, Giza 181 and GZ 1368 were the most widely grown Japonica and Indica types in Egypt during the last period, possesses at that time many positive agronomic characteristics including wide adaptability, high yield potential, tolerance to stresses and good eating quality. But with the passage of time it has lost its vigor. In Rice Research Program, Egypt, dry seeds of the above mentioned varieties were treated with different doses of gamma rays (100, 200, 300, 400, and 500 Gy) for raising M1 generation. M1 plants were established by transplanting in the year 2000 season. One hundred independent lines have been advanced to M5 generation enabling evaluation of quantitative traits by replicated trials and promising lines were selected and tested in multi-location trials as M6, M7 and M8 generations. Morphological variations at vegetative and reproductive stages including plant type and various physiological characters were observed in the five populations. The mutant lines characteristics consisted of better resistance to lodging, blast disease, high yield potential, as well as early maturity. Results from yield trials and molecular assessments indicated that the mutants differed genetically from their parents. So, these mutants could be used as a donor parents in rice breeding program and some of them can be recommended as new rice varieties suitable for rice belt in Egypt. (author)

  8. Selection of rice mutants Oryza Sativa L. with tolerance to saline grounds

    International Nuclear Information System (INIS)

    Hernandez Aguero, L.A.

    2001-01-01

    A selection of rice mutants with tolerance to salinity, took place in the Escuela de Ciencias Agrarias de la Universidad Nacional de Heredia, in conditions of hothouse starting from a population of M2 segregative seed, coming from commercial seed radiated with Co 60 gamma rays. The studied segregatives were: Setesa-9, Experimental II and Experimental I. For making this selection, the seed M2 was planted in plastic trays with saline soil with electrical conductivity values from 8 to 10 mmhos/cm. In each case, non-radiated original seed was used as control. After 22 days the seedling germinated, an evaluation was made and it was seen that any of the controls had resisted to the saline stress, and only those segregatives resistent to salinity survived. These were the next ones: 9 individuals of Setesa, 10 of the Experimental II, and 9 of Experimental I. The index of selection obtained was: 3.6, 4.0 y 3.6 respectively. In a second phase of the experiment, the seedling selected as salinity resistant, were taken to the ground were they were developed for getting the M3 mutant seed tolerant to salinity. The plants were individually harvested in the ground and each one had a specific identification. Then, weight and number data, fertile grain and ineffectives of the M3 seed were taken. After, for corroborating the capacity of tolerance to salinity, M3 seed was planted in flowerpots with saline soil with a value of electrical conductivity between 8 and 10 mmhos/cm. After data were analyzed, it was proved that some rice mutants had a profit of even 28 grams for 1000 grams as: ExpI-17, ExpI-15, ExpI-08, ExpII-22, ExpII-08, ExpII-30 and Se-9-14, Se-9-39 and Se-9-10. Therefore, the methodology utilized showed being effective and efficient for the objectives of the work [es

  9. Self-excising Cre/mutant lox marker recycling system for multiple gene integrations and consecutive gene deletions in Aspergillus oryzae.

    Science.gov (United States)

    Zhang, Silai; Ban, Akihiko; Ebara, Naoki; Mizutani, Osamu; Tanaka, Mizuki; Shintani, Takahiro; Gomi, Katsuya

    2017-04-01

    In this study, we developed a self-excising Cre/loxP-mediated marker recycling system with mutated lox sequences to introduce a number of biosynthetic genes into Aspergillus oryzae. To construct the self-excising marker cassette, both the selectable marker, the Aspergillus nidulans adeA gene, and the Cre recombinase gene (cre), conditionally expressed by the xylanase-encoding gene promoter, were designed to be located between the mutant lox sequences, lox66 and lox71. However, construction of the plasmid failed, possibly owing to a slight expression of cre downstream of the fungal gene promoter in Escherichia coli. Hence, to avoid the excision of the cassette in E. coli, a 71-bp intron of the A. oryzae xynG2 gene was inserted into the cre gene. The A. oryzae adeA deletion mutant was transformed with the resulting plasmid in the presence of glucose, and the transformants were cultured in medium containing xylose as the sole carbon source. PCR analysis of genomic DNA from resultant colonies revealed the excision of both the marker and Cre expression construct, indicating that the self-excising marker cassette was efficient at removing the selectable marker. Using the marker recycling system, hyperproduction of kojic acid could be achieved in A. oryzae by the introduction of two genes that encode oxidoreductase and transporter. Furthermore, we also constructed an alternative marker recycling cassette bearing the A. nidulans pyrithiamine resistant gene (ptrA) as a dominant selectable marker. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  10. Further enhanced production of heterologous proteins by double-gene disruption (ΔAosedD ΔAovps10) in a hyper-producing mutant of Aspergillus oryzae.

    Science.gov (United States)

    Zhu, Lin; Maruyama, Jun-ichi; Kitamoto, Katsuhiko

    2013-07-01

    The filamentous fungus Aspergillus oryzae is used as one of the most favored hosts for heterologous protein production due to its ability to secrete large amounts of proteins into the culture medium. We previously generated a hyper-producing mutant strain of A. oryzae, AUT1, which produced 3.2- and 2.6-fold higher levels of bovine chymosin (CHY) and human lysozyme (HLY), respectively, compared with the wild-type strain. However, further enhancement of heterologous protein production by multiple gene disruption is difficult because of the low gene-targeting efficiency in strain AUT1. Here, we disrupted the ligD gene, which is involved in nonhomologous recombination, and the pyrG gene to create uridine/uracil auxotrophy in strain AUT1, to generate a hyper-producing mutant applicable to pyrG marker recycling with highly efficient gene targeting. We generated single and double disruptants of the tripeptidyl peptidase gene AosedD and vacuolar sorting receptor gene Aovps10 in the hyper-producing mutant background, and found that all disruptants showed significant increases in heterologous protein production. Particularly, double disruption of the Aovps10 and AosedD genes increased the production levels of CHY and HLY by 1.6- and 2.1-fold, respectively, compared with the parental strain. Thus, we successfully generated a fungal host for further enhancing the heterologous protein production ability by combining mutational and molecular breeding techniques.

  11. Variation in accumulation of isoflavonoids in Phaseoleae seedlings elicited by Rhizopus

    NARCIS (Netherlands)

    Aisyah, Siti; Gruppen, Harry; Andini, Silvia; Bettonvil, Monique; Severing, Eduard; Vincken, Jean Paul

    2016-01-01

    Seeds from seven species of tribe Phaseoleae, i.e. Phaseolus, Vigna, Lablab and Psophocarpus, were investigated for inducibility of isoflavonoids by germination with or without subsequent elicitation with Rhizopus oryzae. Germination alone poorly induced isoflavonoid production (in the range of

  12. Production of α-amylase by solid state fermentation by Rhizopus ...

    African Journals Online (AJOL)

    2015-02-18

    Feb 18, 2015 ... However, only a few strains of fungi and bacteria meet the criteria for production of ... amylase production, but solid-state fermentation (SSF) is emerging as a ..... synthesis of lactic acid in R. oryzae and Rhizopus arrhizus using ...

  13. Isolation and characterization of a Ds-tagged rice (Oryza sativa L.) GA-responsive dwarf mutant defective in an early step of the gibberellin biosynthesis pathway.

    Science.gov (United States)

    Margis-Pinheiro, Marcia; Zhou, Xue-Rong; Zhu, Qian-Hao; Dennis, Elizabeth S; Upadhyaya, Narayana M

    2005-03-01

    We have isolated a severe dwarf transposon (Ds) insertion mutant in rice (Oryza sativa L.), which could be differentiated early in the seedling stage by reduced shoot growth and dark green leaves, and later by severe dwarfism and failure to initiate flowering. These mutants, however, showed normal seed germination and root growth. One of the sequences flanking Ds, rescued from the mutant, was of a chromosome 4-located putative ent-kaurene synthase (KS) gene, encoding the enzyme catalyzing the second step of the gibberellin (GA) biosynthesis pathway. Dwarf mutants were always homozygous for this Ds insertion and no normal plants homozygous for this mutation were recovered in the segregating progeny, indicating that the Ds insertion mutation is recessive. As mutations in three recently reported rice GA-responsive dwarf mutant alleles and the dwarf mutation identified in this study mapped to the same locus, we designate the corresponding gene OsKS1. The osks1 mutant seedlings were responsive to exogenous gibberellin (GA3). OsKS1 transcripts of about 2.3 kb were detected in leaves and stem of wild-type plants, but not in germinating seeds or roots, suggesting that OsKS1 is not involved in germination or root growth. There are at least five OsKS1-like genes in the rice genome, four of which are also represented in rice expressed sequence tag (EST) databases. All OsKS1-like genes are transcribed with different expression patterns. ESTs corresponding to all six OsKS genes are represented in other cereal databases including barley, wheat and maize, suggesting that they are biologically active.

  14. Evaluation and characterization of advanced rice mutant line of rice (Oryza sativa), MR219-4 and MR219-9 under drought condition

    International Nuclear Information System (INIS)

    Abdul Rahim Harun; Zarith Shafika Kamarudin; Abdullah, M.Z.; Anna, L.P.K.; Sobri Hussain; Rusli Ibrahim; Khairuddin abdul Rahim

    2012-01-01

    Two advance rice mutant lines, MR219-4 and MR219-9 derived from mutagenesis of Oryza sativa cv. MR219 with gamma radiation at 300 Gy were evaluated in simulated drought condition in the greenhouse at Malaysian Nuclear Agency. The mutants were evaluated simultaneously with ARN1, a drought resistant variety and MR211 a susceptible cultivar as a check. Randomized complete block design with three replicates was used in the experiment. The evaluation and selection were done based on leaf rolling and leaf drying as well as other agronomic traits, such as, number of tillers per plant, plant height, flag leaf area, grain weight per plant, grain yield per plant, 100-grain weight, harvest index, panicle length and plant biomass. The mutants MR219-4 showed moderate tolerance and MR219-9 showed tolerance to drought respectively as compare to the check variety (ARN1, MR211) and control MR219. Leaf rolling, leaf drying, days to flowering and days to maturity are valuable secondary traits that may provide additional information for selection because of associating with the plant survival under water stress. Further research on expression of drought-tolerant lines under different drought conditions is essential in order to identify particular traits that are associated with drought tolerance and high yield potential. Similarly the importance of secondary traits, relative to other putative traits for drought tolerance, needs to be tested in various environments. (author)

  15. Breeding for blast-disease-resistant and high-yield Thai jasmine rice (Oryza sativa L. cv. KDML 105) mutants using low-energy ion beams

    Science.gov (United States)

    Mahadtanapuk, S.; Teraarusiri, W.; Phanchaisri, B.; Yu, L. D.; Anuntalabhochai, S.

    2013-07-01

    Low-energy ion beam was applied on mutation induction for plant breeding of blast-disease-resistant Thai jasmine rice (Oryza sativa L. cv. KDML 105). Seeds of the wild-type rice were bombarded in vacuum by nitrogen ion beam at energy of 60-80 keV to a beam fluence range of 2 × 1016-2 × 1017 ions/cm2. The ion-bombarded rice seeds were grown in soil for 2 weeks as transplanted rice in plastic pots at 1 seedling/pot. The seedlings were then screened for blast resistance by Pyricularia grisea inoculation with 106 spores/ml concentrations. The blast-resistant rice mutant was planted up to F6 generation with the consistent phenotypic variation. The high percentage of the blast-disease-resistant rice was analyzed with DNA fingerprint. The HAT-RAPD (high annealing temperature-random amplified polymorphic DNA) marker revealed the modified polymorphism fragment presenting in the mutant compared with wild type (KDML 105). The cDNA fingerprints were investigated and the polymorphism fragment was subcloned into pGEM-T easy vector and then sequenced. The sequence of this fragment was compared with those already contained in the database, and the fragment was found to be related to the Spotted leaf protein 11 (Spl11).

  16. Identification of prenylated pterocarpans and other isoflavonoids in Rhizopus spp. elicited soya bean seedlings by electrospray ionisation mass spectrometry

    NARCIS (Netherlands)

    Simons, R.; Vincken, J.P.; Bohin, M.C.; Kuijpers, T.F.M.; Verbruggen, M.A.; Gruppen, H.

    2011-01-01

    Phytoalexins from soya are mainly characterised as prenylated pterocarpans, the glyceollins. Extracts of non-soaked and soaked soya beans, as well as that of soya seedlings, grown in the presence of Rhizopus microsporus var. oryzae, were screened for the presence of prenylated flavonoids with a

  17. Kinetic properties of two Rhizopus exo-polygalacturonase enzymes hydrolyzing galacturonic acid oligomers using isothermal titration calorimetry

    Science.gov (United States)

    The kinetic characteristics of two Rhizopus oryzae exo-polygalacturonases acting on galacturonic acid oligomers (GalpA) were determined using isothermal titration calorimetry (ITC). RPG15 hydrolyzing (GalpA)2 demonstrated a Km of 55 uM and kcat of 10.3 s^-1^ while RPG16 was shown to have greater af...

  18. Breeding for blast-disease-resistant and high-yield Thai jasmine rice (Oryza sativa L. cv. KDML 105) mutants using low-energy ion beams

    International Nuclear Information System (INIS)

    Mahadtanapuk, S.; Teraarusiri, W.; Phanchaisri, B.; Yu, L.D.; Anuntalabhochai, S.

    2013-01-01

    Highlights: •N-ion beam bombarded Thai jasmine rice seeds to induce mutation. •Mutants with blast-disease resistance and high yield were screened. •Gene involved in the blast-disease resistance was analyzed. •The gene responsible for the resistance was linked to Spotted leaf protein 11. -- Abstract: Low-energy ion beam was applied on mutation induction for plant breeding of blast-disease-resistant Thai jasmine rice (Oryza sativa L. cv. KDML 105). Seeds of the wild-type rice were bombarded in vacuum by nitrogen ion beam at energy of 60–80 keV to a beam fluence range of 2 × 10 16 –2 × 10 17 ions/cm 2 . The ion-bombarded rice seeds were grown in soil for 2 weeks as transplanted rice in plastic pots at 1 seedling/pot. The seedlings were then screened for blast resistance by Pyricularia grisea inoculation with 10 6 spores/ml concentrations. The blast-resistant rice mutant was planted up to F6 generation with the consistent phenotypic variation. The high percentage of the blast-disease-resistant rice was analyzed with DNA fingerprint. The HAT-RAPD (high annealing temperature-random amplified polymorphic DNA) marker revealed the modified polymorphism fragment presenting in the mutant compared with wild type (KDML 105). The cDNA fingerprints were investigated and the polymorphism fragment was subcloned into pGEM-T easy vector and then sequenced. The sequence of this fragment was compared with those already contained in the database, and the fragment was found to be related to the Spotted leaf protein 11 (Spl11)

  19. Breeding for blast-disease-resistant and high-yield Thai jasmine rice (Oryza sativa L. cv. KDML 105) mutants using low-energy ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Mahadtanapuk, S. [School of Agriculture and Natural Resources, University of Phayao, Phayao 56000 (Thailand); Teraarusiri, W. [Central Laboratory, University of Phayao, Phayao 56000 (Thailand); Phanchaisri, B. [Science and Technology Research Institute, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, L.D., E-mail: yuld@frnf.science.cmu.ac.th [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand); Anuntalabhochai, S., E-mail: burinka@hotmail.com [Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand)

    2013-07-15

    Highlights: •N-ion beam bombarded Thai jasmine rice seeds to induce mutation. •Mutants with blast-disease resistance and high yield were screened. •Gene involved in the blast-disease resistance was analyzed. •The gene responsible for the resistance was linked to Spotted leaf protein 11. -- Abstract: Low-energy ion beam was applied on mutation induction for plant breeding of blast-disease-resistant Thai jasmine rice (Oryza sativa L. cv. KDML 105). Seeds of the wild-type rice were bombarded in vacuum by nitrogen ion beam at energy of 60–80 keV to a beam fluence range of 2 × 10{sup 16}–2 × 10{sup 17} ions/cm{sup 2}. The ion-bombarded rice seeds were grown in soil for 2 weeks as transplanted rice in plastic pots at 1 seedling/pot. The seedlings were then screened for blast resistance by Pyricularia grisea inoculation with 10{sup 6} spores/ml concentrations. The blast-resistant rice mutant was planted up to F6 generation with the consistent phenotypic variation. The high percentage of the blast-disease-resistant rice was analyzed with DNA fingerprint. The HAT-RAPD (high annealing temperature-random amplified polymorphic DNA) marker revealed the modified polymorphism fragment presenting in the mutant compared with wild type (KDML 105). The cDNA fingerprints were investigated and the polymorphism fragment was subcloned into pGEM-T easy vector and then sequenced. The sequence of this fragment was compared with those already contained in the database, and the fragment was found to be related to the Spotted leaf protein 11 (Spl11)

  20. Involvement of NADPH oxidase isoforms in the production of O2- manipulated by ABA in the senescing leaves of early-senescence-leaf (esl) mutant rice (Oryza sativa).

    Science.gov (United States)

    Li, Zhaowei; Wang, Fubiao; Zhao, Qian; Liu, Jianchao; Cheng, Fangmin

    2018-01-01

    In this study, the differences in reactive oxygen species (ROS) generation and abscisic acid (ABA) accumulation in senescing leaves were investigated by early-senescence-leaf (esl) mutant and its wild type, to clarify the relationship among ABA levels, ROS generation, and NADPH oxidase (Nox) in senescing leaves of rice (Oryza sativa). The temporal expression levels of OsNox isoforms in senescing leaves and their expression patterns in response to ABA treatment were determined through quantitative real-time reverse transcription PCR (qRT-PCR). Results showed that the flag leaf of the esl mutant generated more O2- concentrations and accumulated higher ABA levels than the wild-type cultivar did in the grain-filling stage. Exogenous ABA treatment induced O2- generation; however, it was depressed by diphenyleneiodonium chloride (DPI) pretreatment in the detached leaf segments. This finding suggested the involvement of NADPH oxidase in ABA-induced O2- generation. The esl mutant exhibited significantly higher expression of OsNox2, OsNox5, OsNox6, and OsNox7 in the initial of grain-filling stage, followed by sharply decrease. The transcriptional levels of OsNox1, OsNox3, and OsFR07 in the flag leaf of the esl mutant were significantly lower than those in the wild-type cultivar. The expression levels of OsNox2, OsNox5, OsNox6, and OsNox7 were significantly enhanced by exogenous ABA treatments. The enhanced expression levels of OsNox2 and OsNox6 were dependent on the duration of ABA treatment. The inducible expression levels of OsNox5 and OsNox7 were dependent on ABA concentrations. By contrast, exogenous ABA treatment severely repressed the transcripts of OsNox1, OsNox3, and OsFR07 in the detached leaf segments. Therefore, OsNox2, OsNox5, OsNox6, and OsNox7 were probably involved in the ABA-induced O2- generation in the initial stage of leaf senescence. Subsequently, other oxidases activated in deteriorating cells were associated with ROS generation and accumulation in the

  1. Field performance of thirty mutant lines of the rice (Oryza sativa L.) varieties ICTA-Virginia and Precoz-ICTA

    International Nuclear Information System (INIS)

    Montepeque, R.; Molina, L. G.; Lopez, J. J.; Pazos, W.; Ramirez, J.

    1993-01-01

    Fifteen mutant lines from the variety ICTA-Virginia and fifteen from the variety Precozicta were evaluated according to their agronomic characteristics under conditions of the Motagua river valley during 1992. The objective was to select genotypes showing resistance to disease caused by Pyricularia grisea. The analysis of variance did not show significative differences among ICTA-Virginia mutants. The highest yield was form MV-860, 8.17 TM/ha and the lowest 5.31 TM/ha for MV-411. Significant differences were found among mutant lines from Precozicta. The highest yields were 6.06, 5.80 and 5.52 TM/ha for MPI-1189, MPI-1664 and MPI-1346 respectively. Inoculation with Pyricularia was made spraying it over the crop. However, it was not possible the evaluation of the disease in the neck (neck blast) due to absence of the pathogen. 5 tabs.(Author)

  2. Response of a semi-dwarf mutant of rice (Oryza sativa L.) to application of gibberelic acid

    International Nuclear Information System (INIS)

    Orozco, Rafael; Navarro, Willy

    2000-01-01

    The role of gibberellic acid (AG 3 ) on the capacity of elongation of the nodes of a semi-dwarf mutant of rice 2B-95, was studied. This mutant, with a height between 65 to 90 cm, was obtained by Co-60 gamma irradiation from a material called WS tall with an average height of 165 cm. Variety semi-dwarf CR-1113 was used as an additional control. The work was carried out under conditions in vitro applying the AG 3 in concentrations of 0.20, 30 and 40 ppm. The answer of the mutant and of the other two genotypes to exogenous application of the hormone was assessed by measuring the length of the second leaf sheath emerged after germination of the seed according to a special modification of the methodology of Harada and Vergara (1971). The results have indicated that WS genotypes and CR-1113, the length of the sheath of the second leaf at 11 days old, increased by all concentrations of AG 3 evaluated, while in the semi-dwarf mutant 2B-95 the effect was only significant (P 3 . (author) [es

  3. Rhizopus in Kalanchoë

    NARCIS (Netherlands)

    Paternotte, S.J.

    2001-01-01

    In 2001 is door PPO-glastuinbouw onderzoek gedaan aan Rhizopus stolonifer in Kalanchoë ( verslag PPO 533). Naar aanleiding van dit onderzoek en na gesprekken met de begeleidingscommissie en telers van Kalanchoë moerplanten is de conclusie getrokken dat vooral grote schommelingen in watergehalte van

  4. Possible cleavage sites of glutelin partial degradation confirmed by immunological analysis in globulin-less mutants of rice (Oryza sativa L.).

    Science.gov (United States)

    Khan, Nadar; Yamaguchi, Satoru; Katsube-Tanaka, Tomoyuki

    2017-10-01

    Proteolytic cleavage or partial degradation of proteins is one of the important post-translational modifications for various biological processes, but it is difficult to analyze. Previously, we demonstrated that some subunits of the major rice (Oryza sativa L.) seed storage protein glutelin are partially degraded to produce newly identified polypeptides X1-X5 in mutants in which another major seed storage protein globulin is absent. In this study, the new polypeptides X3 and X4/X5 were immunologically confirmed to be derived from GluA3 and GluA1/GluA2 subunits, respectively. Additionally, the new polypeptides X1 and X2 were at least in part the α polypeptides of the GluB4 subunit partially degraded at the C-terminus. Simulated 2D-PAGE migration patterns of intact and partially degraded α polypeptides based on the calculation of their MWs and pIs enabled us to narrow or predict the possible locations of cleavage sites. The predicted cleavage sites were also verified by the comparison of 2D-PAGE patterns between seed-extracted and E. coli-expressed proteins of the intact and truncated α polypeptides. The results and methodologies demonstrated here would be useful for analyses of partial degradation of proteins and the structure-function relationships of rice seed protein bodies. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Studies on some agronomic and quality characteristics of 271 induced early mutants of rice (Oryza sativa L. cv. Nizersail)

    International Nuclear Information System (INIS)

    Rahman, Mostafizur; Miah, A.J.; Mansur, M.A.; Kaul, A.K.

    1980-01-01

    Nizersail, the most popular, recommended rice variety in Bangladesh, was subjected to gamma-irradiation (10 - 25 kR) or ethyl methane sulfonate (EMS) (0.75 - 1.50%) treatments to obtain the mutants with stiff straw and early maturity. In the M 2 generation, 29 gamma-ray- and 8 EMS-induced mutants were selected mainly for short culm length and earliness. Further selections were made in the segregating M 3 and M 4 populations, and finally 400 plants with short culm length were obtained. These 400 selections were grown in M 5 lines, and 271 of these lines were analyzed for several characters. Heading time had singificantly shifted towards earliness in 40 lines. Yield per plant, 1,000-kernel weight, the length/breadth ratio of kernels, alkali spreading index value (indicator of amylose content) and dye-binding capacity (indicator of protein content) were significantly higher than those in the mother variety in 10 - 30% of the lines examined. However, no positive correlation among these characters was observed. Significant negative correlations were observed between heading time and 1,000-kernel weight, and between yield per plant and dye-binding capacity. These results suggest that the early heading plants may produce fewer tillers with bolder seeds, and that high yielding types may not simultaneously show high protein content. (Kaihara, S.)

  6. Low Lactose Milk Production of Soybean by Fermentation Technique Using Rhizopus oligosporus

    Directory of Open Access Journals (Sweden)

    Farid Salahudin

    2013-06-01

    Full Text Available Milk is an important food for baby that contains lactose. Normally, a baby could produce lactase enzyme that digest lactose, but in the diarrhea case lactose could not be digested. So, Low Lactose Milk is needed. Low Lactose Milk usually produced from rice or almonds that have low protein. Soybean (Glycine max is the commodity with rich of protein and also contains raffinose and stachyose, which can lead flatulence. Raffinose and stachyose could be reduced by Rhizopus oryzae at tempe process from lamtoro beans.  So the aim in this research is to know the optimum time of soybean fermentation with R. oryzae to reduce stachyiose  and raffinose. The research was done with innoculation of R. oryzae isolate in the soybeans fermentation for 72 hours. N index, raffinose and stachyose level was tested. The result shows that optimum fermentation time is 48 hour and using 5% skim milk as filler.

  7. Fumaric acid production by Rhizopus oryzae and its facilitated ...

    African Journals Online (AJOL)

    Anupreet

    2014-03-05

    Mar 5, 2014 ... membrane' setup for a 'fumaric acid' source, with toluene as organic membrane and sodium hydroxide as strip phase. The liquid ... polymer films can be extended to include liquids. They are defined as Liquid .... Membrane solutions were prepared by dissolution of trioctylamine. (TOA) (Fluka A.G. ...

  8. Fumaric acid production by Rhizopus oryzae and its facilitated ...

    African Journals Online (AJOL)

    Anupreet

    2014-03-05

    Mar 5, 2014 ... Currently, fumaric acid is produced from petroleum based derivative maleic ... best possible option that came up for the strip phase was an alkaline medium. .... Future directions of membrane gas separation technology. Indus.

  9. Radiation resistance of Rhizopus stolonifer

    International Nuclear Information System (INIS)

    Robbertse, P.J.; Du Toit, T.L.; Van der Merwe, L.J.; Koekemoer, M.L.; Eilers, I.M.I.

    1983-01-01

    A problem encountered with the irradiation of food is that certain micro-organisms are highly resistant to gamma rays. This includes the fungus, Rhizopus stolonifer, associated with most fruits. The Nuclear Development Corporation of South Africa (NUCOR) has found that a combination of radiation and mild heat treatment reduces the radiation dose necessary to kill 90% of R. stolonifer by approximately half. Treatment at 50 degrees Celsius for 10 minutes or at 55 degrees Celsius for five minutes is sufficient. The article discusses the mechanism of radiation resistance in R. stolonifer and the way in which heating affects this resistance

  10. Proteolysis in tempeh-type products obtained with Rhizopus and Aspergillus strains from grass pea (Lathyrus sativus) seeds.

    Science.gov (United States)

    Starzyńska-Janiszewska, Anna; Stodolak, Bożena; Wikiera, Agnieszka

    2015-01-01

    Tempeh is a food product obtained from legumes by means of solid-state fermentation with Rhizopus sp. Our previous research proved that mixed-culture inoculum may also be successfully applied. The objective of present research was to study the proteolytic activity of R. microsporus var. chinensis and A. oryzae during tempeh-type fermentation of grass pea seeds, and the effect of inoculum composition on the protein level and in vitro protein bioavailability in products. Fermentation substrate were soaked and cooked grass pea seeds. Material was mixed with single- or mixed-culture inoculum, and incubated in perforated plastic bags at 30°C for 32 hrs. In the products, the proteolytic activity (pH 3, 5 and 7), glucosamine, total protein and free amino acids levels, as well as protein in vitro bioavailability and degree of protein hydrolysis were obtained. The significant correlation was found between glucosamine content and proteolytic activity in grass pea seeds fermented with Rhizopus or Aspergillus. The activities of Rhizopus proteases were higher than Aspergillus ones, which corresponded with the degree of seed protein hydrolysis. Both strains showed the highest activity of protease at pH 3. Tempeh made with pure culture of Rhizopus had 37% protein of 69% in-vitro bioavailability. Mixed-culture fermentation improved nutritional parameters of products only when the dose of Aspergillus spores in the inoculum was equal and lower than that of Rhizopus. This process resulted in higher in-vitro bioavailability of protein, slightly more efficient protein hydrolysis and higher level of free amino acids, as compared to standard tempeh. The activity of A. oryzae in tempeh-type fermentation is beneficial as long as it does not dominate the activity and/or growth of Rhizopus strain.

  11. Hydrolysis of Soybean Protein by Aspergillus Sojae, a. Oryzae, and Rhizpus Oligosporus

    OpenAIRE

    Rahayu, Endang Sutriswati

    1991-01-01

    Three species of molds, i.e. Aspergillus sojae. A. oryzae and Rhizopus oligosporus were used to hydrolyze soybean proteins. Whole soybeans were soaked overnight and cooked in boiling water for an hour, drained, sterilized at 121°C for 15 minutes, then cooled and inoculated with A. oryzae. A. sojae, and R. oligosporus. As a control treatment another batch of soybeans was prepared for spontaneous fermentation. Fermentation tasted for five days. Based on the colony forming units (CFU), A. sojae,...

  12. CatB is Critical for Total Catalase Activity and Reduces Bactericidal Effects of Phenazine-1-Carboxylic Acid on Xanthomonas oryzae pv. oryzae and X. oryzae pv. oryzicola.

    Science.gov (United States)

    Pan, Xiayan; Wu, Jian; Xu, Shu; Duan, Yabing; Zhou, Mingguo

    2017-02-01

    Rice bacterial leaf blight, caused by Xanthomonas oryzae pv. oryzae, and rice bacterial leaf streak, caused by X. oryzae pv. oryzicola, are major diseases of rice. Phenazine-1-carboxylic acid (PCA) is a natural product that is isolated from Pseudomonas spp. and is used to control many important rice diseases in China. We previously reported that PCA disturbs the redox balance, which results in the accumulation of reactive oxygen species in X. oryzae pv. oryzae. In this study, we found that PCA significantly upregulated the transcript levels of catB and katE, which encode catalases, and that PCA sensitivity was reduced when X. oryzae pvs. oryzae and oryzicola were cultured with exogenous catalase. Furthermore, catB deletion mutants of X. oryzae pvs. oryzae and oryzicola showed dramatically decreased total catalase activity, increased sensitivity to PCA, and reduced virulence in rice. In contrast, deletion mutants of srpA and katG, which also encode catalases, exhibited little change in PCA sensitivity. The results indicate that catB in both X. oryzae pvs. oryzae and oryzicola encodes a catalase that helps protect the bacteria against PCA-induced stress.

  13. Phylogenetic and Phylogenomic Definition of Rhizopus Species

    Directory of Open Access Journals (Sweden)

    Andrii P. Gryganskyi

    2018-06-01

    Full Text Available Phylogenomic approaches have the potential to improve confidence about the inter-relationships of species in the order Mucorales within the fungal tree of life. Rhizopus species are especially important as plant and animal pathogens and bioindustrial fermenters for food and metabolite production. A dataset of 192 orthologous genes was used to construct a phylogenetic tree of 21 Rhizopus strains, classified into four species isolated from habitats of industrial, medical and environmental importance. The phylogeny indicates that the genus Rhizopus consists of three major clades, with R. microsporus as the basal species and the sister lineage to R. stolonifer and two closely related species R. arrhizus and R. delemar. A comparative analysis of the mating type locus across Rhizopus reveals that its structure is flexible even between different species in the same genus, but shows similarities between Rhizopus and other mucoralean fungi. The topology of single-gene phylogenies built for two genes involved in mating is similar to the phylogenomic tree. Comparison of the total length of the genome assemblies showed that genome size varies by as much as threefold within a species and is driven by changes in transposable element copy numbers and genome duplications.

  14. Involvement of NADPH oxidase isoforms in the production of O2− manipulated by ABA in the senescing leaves of early-senescence-leaf (esl) mutant rice (Oryza sativa)

    Science.gov (United States)

    Wang, Fubiao; Zhao, Qian; Liu, Jianchao; Cheng, Fangmin

    2018-01-01

    In this study, the differences in reactive oxygen species (ROS) generation and abscisic acid (ABA) accumulation in senescing leaves were investigated by early-senescence-leaf (esl) mutant and its wild type, to clarify the relationship among ABA levels, ROS generation, and NADPH oxidase (Nox) in senescing leaves of rice (Oryza sativa). The temporal expression levels of OsNox isoforms in senescing leaves and their expression patterns in response to ABA treatment were determined through quantitative real-time reverse transcription PCR (qRT-PCR). Results showed that the flag leaf of the esl mutant generated more O2- concentrations and accumulated higher ABA levels than the wild-type cultivar did in the grain-filling stage. Exogenous ABA treatment induced O2- generation; however, it was depressed by diphenyleneiodonium chloride (DPI) pretreatment in the detached leaf segments. This finding suggested the involvement of NADPH oxidase in ABA-induced O2- generation. The esl mutant exhibited significantly higher expression of OsNox2, OsNox5, OsNox6, and OsNox7 in the initial of grain-filling stage, followed by sharply decrease. The transcriptional levels of OsNox1, OsNox3, and OsFR07 in the flag leaf of the esl mutant were significantly lower than those in the wild-type cultivar. The expression levels of OsNox2, OsNox5, OsNox6, and OsNox7 were significantly enhanced by exogenous ABA treatments. The enhanced expression levels of OsNox2 and OsNox6 were dependent on the duration of ABA treatment. The inducible expression levels of OsNox5 and OsNox7 were dependent on ABA concentrations. By contrast, exogenous ABA treatment severely repressed the transcripts of OsNox1, OsNox3, and OsFR07 in the detached leaf segments. Therefore, OsNox2, OsNox5, OsNox6, and OsNox7 were probably involved in the ABA-induced O2- generation in the initial stage of leaf senescence. Subsequently, other oxidases activated in deteriorating cells were associated with ROS generation and accumulation in the

  15. Production of extracellular lipases by Rhizopus oligosporus in a stirred fermentor

    OpenAIRE

    Iftikhar, Tehreema; Niaz, Mubashir; Zia, Muhammad Anjum; Haq, Ikram ul

    2010-01-01

    The present investigation deals with the kinetics of submerged extracellular lipases fermentation by both wild and mutant strains of Rhizopus oligosporus var. microsporus in a laboratory scale stirred fermentor. Other parameters studied were inoculum size, pH, agitation and rate of aeration. It was found that the growth and lipases production was increased gradually and reached its maximum 9.07± 0.42ª U mL-1 (W) and 42.49 ± 3.91ª U mL-1 (M) after 30h of fermentation for both wild and mutant s...

  16. Study on the Wx Allele Gene Sequences of Two Low Amylose Content Mutants of Oryza indica%2个籼稻低直链淀粉突变体Wx等位基因序列的研究

    Institute of Scientific and Technical Information of China (English)

    郭涛; 韩诗曼; 夏斌; 王慧; 刘永柱; 张建国; 陈志强

    2011-01-01

    根据粳型水稻Wx基因全序列设计引物,扩增2个空间诱变低直链淀粉突变体XLA-1和XLA-2的Wx等位基因.序列分析结果表明:XLA-1、XLA-2与原种籼小占在Wx基因DNA序列上存在较多碱基差异,这种差异以碱基改变为主;XLA-1、XLA-2在第10外显子(+1 208 bp)处存在一个单核苷酸突变(籼小占为碱基T,突变体为碱基C),编码子由TCT突变为CCT,导致丝氨酸突变成脯氨酸,氨基酸的改变可能改变了Wx蛋白的空间结构,致使它不能充分结合在淀粉颗粒上,进而导致直链淀粉含量下降.本研究初步证明在2个籼稻突变体中存在Wx的复等位基因影响直链淀粉含量.%Based on the Wx gene sequence of japonica rice, the Wx gene sequences of the two low-amy-lose mutants XLA-1 and XLA-2 of Oryza indica were detected by PCR and sequencing analysis. The main results showed that: There were many mutant sites among XLA-1, XLA- 2 and Xianxiaozhan (the wild type) , most of them were base change. There was a sigle nucleotide polymorphisms(SNP) in the 10th exon( +1 208 bp) of XLA-1 and XLA-2(Xianxiaozhan for the T, mutant for the C), codon TCT changed into CCT, which resulted in the substitution of a proline residue for serine. The substitution could alter the spatial structure of Wx protein, which may not be fully integrated on the starch granules, leading to the decreased of amylose content. The preliminary results indicated that the existence of Wx allelles affected amylose content in the two mutants.

  17. Respuesta de un mutante semi-enano de arroz (Oryza sativa L. a la aplicación de ácido giberelico.

    Directory of Open Access Journals (Sweden)

    Rafael Orozco

    2016-03-01

    Full Text Available En esta investigación se estudió el papel que juega el ácido giberélico (AG3 en la capacidad de elongación de los nudos del mutante semi-enano de arroz 2B-95. Este mutante, con una altura entre 65 a 90 cm, fue obtenido por irradiaciones gamma Co-60 a partir de un material de porte alto denominado WS con una altura promedio de 165 cm. Como testigo adicional se utilizó la variedad semi-enana CR-1113. El trabajo fue realizado en condiciones in vitro usando el AG3 en concentraciones de 0,20, 30 y 40 ppm la respuesta del mutante y de los otros dos genotipos a la aplicación exógena de la hormona se llevó a cabo midiendo la longitud de la vaina de la segunda hoja emergida después de la germinación de la semilla según una modificación de la metodología de HARADA y VERGARA (1971. Los resultados indican que en los genotipos WS y CR-1113, el largo de la vaina de la segunda hoja a los 11 días de edad, aumentó con todas las concentraciones de AG3 evaluadas, mientras que en el mutante semi-enano 2B-95 el efecto sólo fue significativo (P<0,05 en las concentraciones de 20 y 30 ppm. La concentración de 40 ppm en este genotipo no funcionó como activador del sistema genético vinculado con el  metabolismo del AG3

  18. Characterization and mapping of a novel light-dependent lesion mimic mutant Imm6 in rice (Oryza sativa L.)

    Institute of Scientific and Technical Information of China (English)

    XIAO Gui-qing[1,2; ZHANG Hal-wen[3; LU Xiang-yang[1,2; HUANG Rong-feng[3

    2015-01-01

    A novel rice lesion mimic mutant (LMM) was isolated from an ethane methyl sulfonate (EMS)-induced 02428 mutant bank. The mutant, tentatively designated as Imm6, develops necrotic lesions in the whole growth period along with changes in several important agronomic traits. We found that the initiation of the lesions was induced by light and cell death occurred in Imm6 accompanied with accumulation of reactive oxygen species (ROS). The lower chlorophyll content, soluble protein content and superoxide dismutase (SOD) activity, the higher malondialdehyde (MDA) content were detected in Imm6 than in the wild type (WT). Moreover, the observation by transmission electronic microscope (TEM) demonstrated that some organelles were damaged and the stroma lamella of chloroplast was irregular and loose in mesophyll cell of Imm6. In addition, Imm6 was more resistant than WT to rice blast fungus Magnaporthe grisea infection, which was consistent with increased expression of four genes involved in the defense-related reaction. Genetic analysis showed that mutant trait of Imm6 is inherited as a monogenic recessive nuclear gene located on the long arm of chromosome 6. Using simple sequence repeat (SSR) markers, the target gene was finally delimited to an interval of 80.8 kb between markers MM2359 and MM2370, containing 7 annotated genes. Taken together, our results provide the information to identify a new gene involved in rice lesion mimic, which will be helpful in clarifying the mechanism of cell death and disease resistance in rice.

  19. Molecular and genetic characterization of OSH6 ( Oryza sativa ...

    African Journals Online (AJOL)

    Genetic studies of dissociation (Ds) insertion mutant rice plants indicated that ectopic expression of truncated OSH6 (Oryza sativa Homeobox 6) mRNA may be responsible for the mutant phenotype of knotted leaf formation at the peduncle. Additionally, ectopic expression of truncated OSH6 mRNA in the OSH6-Ds mutant ...

  20. Xanthomonas oryzae pv oryzae the Causal Agent of Bacterial Leaf Blight of rice: Isolation, Characterization, and Study of Transposon Mutagenesis

    Directory of Open Access Journals (Sweden)

    Abdjad Asih Nawangsih

    2011-04-01

    Full Text Available Xanthomonas oryzae pv oryzae the Causal Agent of Bacterial Leaf Blight of rice: Isolation, Characterization, and Study of Transposon Mutagenesis. X. oryzae pv. oryzae (Xoo causes bacterial leaf blight (BLB of rice (Oryza sativa L., a major disease that constrains production of the staple crop in many countries of the world. Identification of X. oryzae pv. oryzae (Xoo was conducted based on the disease symptoms, pathogenicity, morphological, physiological, and genetic characteristics of bacterial cultures isolated from the infected plants. Fifty bacterial isolates predicted as Xoo have been successfully isolated. They are aerobic, rod shaped, and Gram negative bacteria. The isolates were evaluated for their hypersensitivity in tobacco and pathogenicity in rice plant. Fifty isolates induced hypersensitive reaction in tobacco and showed pathogenicity symptom in rice in different length. Based on physiological test, hypersensitivity and pathogenicity reactions, three bacterial isolates strongly predicted as Xoo, i.e. STG21, STG42, and STG46, were non indole formation, non pigment fluorescent, hydrolyzed casein, catalase activity positive, but negative oxidase. Partial sequencing of 16S rRNA genes of STG21 and STG42 showed 80% and 82% homology with X. oryzae, respectively, while STG46 showed 84% homology with X. campestris. Mini-Tn5 transposon mutagenesis of STG21 generated one of the mutants (M5 lossed it’s ability to induce hypersensitive reaction in tobacco plant and deficient in pathogenicity on rice. The lesion length of rice leaf caused by the mutant M5 decreased up to 80%.

  1. Enhanced production of fructosyltransferase in Aspergillus oryzae by genome shuffling.

    Science.gov (United States)

    Wang, Shenghai; Duan, Mengjie; Liu, Yalan; Fan, Sen; Lin, Xiaoshan; Zhang, Yi

    2017-03-01

    To breed Aspergillus oryzae strains with high fructosyltransferase (FTase) activity using intraspecific protoplast fusion via genome-shuffling. A candidate library was developed using UV/LiCl of the conidia of A. oryzae SBB201. By screening for enzyme activity and cell biomass, two mutants (UV-11 and UV-76) were chosen for protoplast fusion and subsequent genome shuffling. After three rounds of genome recombination, a fusion mutant RIII-7 was obtained. Its FTase activity was 180 U g -1 , approximately double that of the original strain, and RIII-7 was genetically stable. In fermentation culture, FTase activity of the genome-shuffled strain reached a maximum of 353 U g -1 using substrate-feeding method, and this value was approximately 3.4-times higher than that of the original strain A. oryzae SBB201. Intraspecific protoplast fusion of A. oryzae significantly enhanced FTase activity and generated a potentially useful strain for industrial production.

  2. Production of extracellular lipases by Rhizopus oligosporus in a stirred fermentor

    Directory of Open Access Journals (Sweden)

    Tehreema Iftikhar

    2010-12-01

    Full Text Available The present investigation deals with the kinetics of submerged extracellular lipases fermentation by both wild and mutant strains of Rhizopus oligosporus var. microsporus in a laboratory scale stirred fermentor. Other parameters studied were inoculum size, pH, agitation and rate of aeration. It was found that the growth and lipases production was increased gradually and reached its maximum 9.07± 0.42ª U mL-1 (W and 42.49 ± 3.91ª U mL-1 (M after 30h of fermentation for both wild and mutant strain. There is overall increase of 109% (W and 124% (M in the production of extracellular lipases as compared to shake flask. Another significant finding of the present study is that the fermentation period is reduced to 30 h in case of wild and 23 h in case of mutant from 48 h in shake flask studies. The specific productivity of mutant strain (qp = 377.3 U/g cells/h was several folds higher than wild strain. The specific production rate and growth coefficient revealed the hyperproducibility of extracellular lipases using mutant IIB-63NTG-7.

  3. Genetic analysis of conidiation regulatory pathways in koji-mold Aspergillus oryzae.

    Science.gov (United States)

    Ogawa, Masahiro; Tokuoka, Masafumi; Jin, Feng Jie; Takahashi, Tadashi; Koyama, Yasuji

    2010-01-01

    Conidia of koji-mold Aspergillus oryzae are often used as starters in the fermented food industry. However, little is known about conidiation regulation in A. oryzae. To improve the productivity of conidia in A. oryzae, it is necessary to understand conidiation regulation in the strain. Therefore, we analyzed the conidiation regulatory system in A. oryzae using 10 kinds of conidiation regulatory gene disruptants. The phenotypes of AorfluG, AorflbA, AorflbB, AorflbC, AorflbD, AorflbE, AorbrlA, AorabaA, AorwetA, and AorfadA mutants are almost identical to those of the corresponding mutants in Aspergillus nidulans. The results indicated that the functions of conidiation regulatory genes are almost conserved between A. oryzae and A. nidulans. However, the severely reduced conidiation phenotype of the AorfluG disruptant in A. oryzae differs from the phenotype of the corresponding mutant in Aspergillus fumigatus in air-exposed culture conditions. These results suggest that A. oryzae, A. nidulans, and A. fumigatus have a G-protein signaling pathway and brlA orthologs in common, and only A. fumigatus has particular brlA activation pathways that are independent of the fluG ortholog. Furthermore, the analyses of AorflbA disruptant and AorfadA dominant-active mutants implicated that AorFadA-mediated G-protein signaling suppresses vegetative growth of A. oryzae.

  4. Identification of prenylated pterocarpans and other isoflavonoids in Rhizopus spp. elicited soya bean seedlings by electrospray ionisation mass spectrometry.

    Science.gov (United States)

    Simons, Rudy; Vincken, Jean-Paul; Bohin, Maxime C; Kuijpers, Tomas F M; Verbruggen, Marian A; Gruppen, Harry

    2011-01-15

    Phytoalexins from soya are mainly characterised as prenylated pterocarpans, the glyceollins. Extracts of non-soaked and soaked soya beans, as well as that of soya seedlings, grown in the presence of Rhizopus microsporus var. oryzae, were screened for the presence of prenylated flavonoids with a liquid chromatography/mass spectrometry (LC/MS)-based screening method. The glyceollins I-III and glyceollidins I-II, belonging to the isoflavonoid subclass of the pterocarpans, were tentatively assigned. The formation of these prenylated pterocarpans was accompanied by that of other prenylated isoflavonoids of the subclasses of the isoflavones and the coumestans. It was estimated that approx. 40% of the total isoflavonoid content in Rhizopus-challenged soya bean seedlings were prenylated pterocarpans, whereas 7% comprised prenylated isoflavones and prenylated coumestans. The site of prenylation (A-ring or B-ring) of the prenylated isoflavones was tentatively annotated using positive-ion mode MS by comparing the (1,3) A(+) retro-Diels-Alder (RDA) fragments of prenylated and non-prenylated isoflavones. Furthermore, the fragmentation pathways of the five pterocarpans in negative-ion (NI) mode were proposed, which involved the cleavage of the C-ring and/or D-ring. The absence of the ring-closed prenyl (pyran or furan) gave exclusively -H(2) O(x,y) RDA fragments, whereas its presence gave predominantly the common RDA fragments. Copyright © 2010 John Wiley & Sons, Ltd.

  5. Biosorptive removal of Hg(II) ions by Rhizopus oligosporus ...

    African Journals Online (AJOL)

    In this study, corn processing wastewater was used as a new low-cost substrate to produce Rhizopus oligosporus. Dried biomass of R. oligosporus was evaluated as a biosorbent for treatment of synthetically contaminated waters with Hg(II) ions. The biosorption process was carried out in a batch process and the effects of ...

  6. A mutation in the aroE gene affects pigment production, virulence, and chemotaxis in Xanthomonas oryzae pv. oryzae.

    Science.gov (United States)

    Kim, Hong-Il; Noh, Tae-Hwan; Lee, Chang-Soo; Park, Young-Jin

    2015-01-01

    Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight (BB) in rice. To study its function, a random insertion mutation library of Xoo was constructed using the Tn5 transposon. A mutant strain with decreased virulence against the susceptible rice cultivar IR24 was isolated from the library (aroE mutant), which also had extremely low pigment production. Thermal asymmetric interlaced-polymerase chain reaction (TAIL-PCR) and sequence analysis of the mutant revealed that the transposon was inserted into the aroE gene (encoding shikimate dehydrogenase). To investigate gene expression changes in the pigment- and virulence-deficient mutant, DNA microarray analysis was performed, which showed downregulation of 20 genes involved in the chemotaxis of Xoo. Our findings reveal that mutation of the aroE gene affects virulence and pigment production, as well as expression of genes involved in Xoo chemotaxis. Copyright © 2014 Elsevier GmbH. All rights reserved.

  7. Mutation induced enhanced biosynthesis of lipases by Rhizopus oligosporus var. microsporus

    International Nuclear Information System (INIS)

    Iftikhar, T.; Ikram-ul-Haq; Niaz, M.; Abbas, S.Q.; Zia, M.A.; Ashraf, I.; Lee, K.J.

    2010-01-01

    The present study describes the isolation, identification and screening of fugal strain Rhizopus oligosporus (var. microsporus) for the production of extracellular lipases. One hundred and sixty seven cultures of fungi were isolated from different environments such as soil, air, milk, pickle, oily bread, decayed fruits and vegetables by serial dilution method. The strains were initially selected qualitatively on Tween 80-Agar plates and were shifted to the slants of PDA for maintenance and storage at 4 deg. C. Quantitative screening for extracellular lipase production by isolated strains was carried out in shake flasks and the most potent strain producing 3.20 +- 0.003 U mL/sup -1/ of enzyme was selected. The strain was then identified on the basis of standard morphological measurements and was assigned the code IIB-63. The selected strain was then subjected to physical (UV and Gamma radiations) and chemical mutagenic (MNNG/NTG, NA, EtBr) treatments in order to improve its lipolytic potential. During the treatment, mutants were qualitatively and quantitatively selected and IIB-63 NTG-7 was found to be the mutant showing highest lipases production (10.37 +- 0.06a U mL/sup -1/) with a zone size of 12.3 mm on Luria-Bertani-tributyrin agar plates. This mutant showed an overall 325% increase in activity over its parent strain for the production of extracellular lipase. (author)

  8. POTENSI DARI KAPANG Aspergilus niger, Rhizophus oryzae DAN Neurospora sitophila SEBAGAI PENGHASIL EZIM FITASE DAN AMILASE PADA SUBSTRATE AMPAS TAHU

    Directory of Open Access Journals (Sweden)

    Atit - Kanti

    2017-02-01

    Full Text Available Penambahan enzim hidrolisis untuk pakan ternak dapat meningkatkan nilai nutrisi pakan. Penelitian bertujuan untuk mendapatkan kondisi optimal untuk produksi enzim amilase dan fitase pada media ampas tahu menggunakan Aspergilus niger, Rhizophus oryzae dan Neurospora sitophila. Uji kemampuan produksi enzim fitase dan amilase oleh Aspergilus niger, Rhizophus oryzae dan Neurospora sitophila dilakukan menggunakan media ampas tahu yang disterilisasi. Pemilihan ketiga isolat ini diawali dengan uji produksi enzim amilase pada kultur cair yang mengandung 2 % pati, dan uji fitase dilakukan pada media yang mengandung 0.5 % sodium fitat. Hasil uji pada medium cair selanjutnya digunakan untuk uji produksi enzim fitase dan fitase pada sistem fermentasi padat (SSF menggunakan ampas tahu sebagai media fermentasi. Untuk mendapatkan produksi enzim yang tinggi dilakukan melalui optimasi waktu inkubasi, suhu inkubasi dan pH media. Fitase dan amilase dapat diproduksi dengan media ampas tahu oleh R. oryzae, A. niger dan N. sitophila. Kondisi optimum untuk produksi fitase, yaitu waktu inkubasi pada hari keempat untuk ketiga kapang, suhu 25 °C untuk R. oryzae dan A. niger, suhu 30°C untuk N. sitophila, pH 8 untuk R. oryzae, pH 6 untuk Aspergillus niger dan N. Sitophila. Neurospora sitophila menghasilkan amilase optimum pada suhu 35°C, sedangkan Aspergillus niger dan Rhizopus oryzae optimum pada suhu 30°C. Penurunan aktivitas produksi amilase menurun oleh R. oryzae pada suhu 40°C. Amilase diproduksi optimal pada pH 6-7. Pakan ternak yang mengandung asam fitat mampu dihidrolisis oleh fitase pada kondisi optimum. Ketiga kapang juga menghasilkan enzim amilase pada media ampas tahu mengindikasikan bahwa ampas tahu merupakan susbtrat yang baik untuk produksi enzim hidrolisis yang berguna untuk meningkatkan nilai nutrisi pakan ternak. (Kata kunci: Amilase, Aspergilus niger, Neurospora sitophila, phytase, Rhizophus oryzae

  9. Random Mutagenesis of the Aspergillus oryzae Genome Results in Fungal Antibacterial Activity

    OpenAIRE

    Leonard, Cory A.; Brown, Stacy D.; Hayman, J. Russell

    2013-01-01

    Multidrug-resistant bacteria cause severe infections in hospitals and communities. Development of new drugs to combat resistant microorganisms is needed. Natural products of microbial origin are the source of most currently available antibiotics. We hypothesized that random mutagenesis of Aspergillus oryzae would result in secretion of antibacterial compounds. To address this hypothesis, we developed a screen to identify individual A. oryzae mutants that inhibit the growth of Methicillin-res...

  10. Rice (Oryza) hemoglobins

    Science.gov (United States)

    Hemoglobins (Hbs) corresponding to non-symbiotic (nsHb) and truncated (tHb) Hbs have been identified in rice (Oryza). This review discusses the major findings from the current studies on rice Hbs. At the molecular level, a family of the nshb genes, consisting of hb1, hb2, hb3, hb4 and hb5, and a sin...

  11. Efficient heterologous expression and secretion in Aspergillus oryzae of a llama variable heavy-chain antibody fragment V(HH) against EGFR.

    Science.gov (United States)

    Okazaki, Fumiyoshi; Aoki, Jun-ichi; Tabuchi, Soichiro; Tanaka, Tsutomu; Ogino, Chiaki; Kondo, Akihiko

    2012-10-01

    We have constructed a filamentous fungus Aspergillus oryzae that secretes a llama variable heavy-chain antibody fragment (V(HH)) that binds specifically to epidermal growth factor receptor (EGFR) in a culture medium. A major improvement in yield was achieved by fusing the V(HH) with a Taka-amylase A signal sequence (sTAA) and a segment of 28 amino acids from the N-terminal region of Rhizopus oryzae lipase (N28). The yields of secreted, immunologically active anti-EGFR V(HH) reached 73.8 mg/1 in a Sakaguchi flask. The V(HH) fragments were released from the sTAA or N28 proteins by an indigenous A. oryzae protease during cultivation. The purified recombinant V(HH) fragment was specifically recognized and could bind to the EGFR with a high affinity.

  12. 21 CFR 184.1420 - Lipase enzyme preparation derived from Rhizopus niveus.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Lipase enzyme preparation derived from Rhizopus... GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS § 184.1420 Lipase enzyme preparation derived from Rhizopus niveus. (a) Lipase enzyme preparation contains lipase enzyme (CAS Reg. No...

  13. Screening of gamma radiation-induced pathogen resistance rice lines against Xanthomonas oryzae pv. oryzae

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Chan Ju; Lee, Ha Yeon; Kim, Woong Bom; Ahmad, Raza; Moon, Jae Sun; Kwon, Suk Yoon [Korea Research Institute of Beoscience and Biotechnology, Daejeon (Korea, Republic of); Kim, Dong Sub [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2010-09-15

    Bacterial blight is one of the most serious diseases of rice (Oryza sativa L.), and it has been known that Xanthomonas oryzae pv. oryzae (Xoo) causes this disease symptom. To develop resistance rice cultivars against Xoo, 3,000 lines of M{sub 3}, which were irradiated with gamma ray, were tested by 'scissor-dip method' primarily, and 191 putative resistant lines were selected. In M{sub 4} generation, these lines were screened again with various ways such as measuring of symptom of bacterial blight in leaf, number of tiller, fresh weight, and phenotypic segregation ratio in next generation. Finally, six resistance lines were selected. RT-PCR analysis revealed that these lines displayed high level of R-genes such as Xa21, Pi36, and Pi-ta. These results indicate that mutations by gamma ray cause disruptions of regulatory signal transduction systems of these R-genes. Furthermore, these selected mutants could be useful for the development of rice cultivar resistant to Xoo.

  14. Random Mutagenesis of the Aspergillus oryzae Genome Results in Fungal Antibacterial Activity

    Directory of Open Access Journals (Sweden)

    Cory A. Leonard

    2013-01-01

    Full Text Available Multidrug-resistant bacteria cause severe infections in hospitals and communities. Development of new drugs to combat resistant microorganisms is needed. Natural products of microbial origin are the source of most currently available antibiotics. We hypothesized that random mutagenesis of Aspergillus oryzae would result in secretion of antibacterial compounds. To address this hypothesis, we developed a screen to identify individual A. oryzae mutants that inhibit the growth of Methicillin-resistant Staphylococcus aureus (MRSA in vitro. To randomly generate A. oryzae mutant strains, spores were treated with ethyl methanesulfonate (EMS. Over 3000 EMS-treated A. oryzae cultures were tested in the screen, and one isolate, CAL220, exhibited altered morphology and antibacterial activity. Culture supernatant from this isolate showed antibacterial activity against Methicillin-sensitive Staphylococcus aureus, MRSA, and Pseudomonas aeruginosa, but not Klebsiella pneumonia or Proteus vulgaris. The results of this study support our hypothesis and suggest that the screen used is sufficient and appropriate to detect secreted antibacterial fungal compounds resulting from mutagenesis of A. oryzae. Because the genome of A. oryzae has been sequenced and systems are available for genetic transformation of this organism, targeted as well as random mutations may be introduced to facilitate the discovery of novel antibacterial compounds using this system.

  15. Random Mutagenesis of the Aspergillus oryzae Genome Results in Fungal Antibacterial Activity

    Science.gov (United States)

    Leonard, Cory A.; Brown, Stacy D.; Hayman, J. Russell

    2013-01-01

    Multidrug-resistant bacteria cause severe infections in hospitals and communities. Development of new drugs to combat resistant microorganisms is needed. Natural products of microbial origin are the source of most currently available antibiotics. We hypothesized that random mutagenesis of Aspergillus oryzae would result in secretion of antibacterial compounds. To address this hypothesis, we developed a screen to identify individual A. oryzae mutants that inhibit the growth of Methicillin-resistant Staphylococcus aureus (MRSA) in vitro. To randomly generate A. oryzae mutant strains, spores were treated with ethyl methanesulfonate (EMS). Over 3000 EMS-treated A. oryzae cultures were tested in the screen, and one isolate, CAL220, exhibited altered morphology and antibacterial activity. Culture supernatant from this isolate showed antibacterial activity against Methicillin-sensitive Staphylococcus aureus, MRSA, and Pseudomonas aeruginosa, but not Klebsiella pneumonia or Proteus vulgaris. The results of this study support our hypothesis and suggest that the screen used is sufficient and appropriate to detect secreted antibacterial fungal compounds resulting from mutagenesis of A. oryzae. Because the genome of A. oryzae has been sequenced and systems are available for genetic transformation of this organism, targeted as well as random mutations may be introduced to facilitate the discovery of novel antibacterial compounds using this system. PMID:23983696

  16. Random Mutagenesis of the Aspergillus oryzae Genome Results in Fungal Antibacterial Activity.

    Science.gov (United States)

    Leonard, Cory A; Brown, Stacy D; Hayman, J Russell

    2013-01-01

    Multidrug-resistant bacteria cause severe infections in hospitals and communities. Development of new drugs to combat resistant microorganisms is needed. Natural products of microbial origin are the source of most currently available antibiotics. We hypothesized that random mutagenesis of Aspergillus oryzae would result in secretion of antibacterial compounds. To address this hypothesis, we developed a screen to identify individual A. oryzae mutants that inhibit the growth of Methicillin-resistant Staphylococcus aureus (MRSA) in vitro. To randomly generate A. oryzae mutant strains, spores were treated with ethyl methanesulfonate (EMS). Over 3000 EMS-treated A. oryzae cultures were tested in the screen, and one isolate, CAL220, exhibited altered morphology and antibacterial activity. Culture supernatant from this isolate showed antibacterial activity against Methicillin-sensitive Staphylococcus aureus, MRSA, and Pseudomonas aeruginosa, but not Klebsiella pneumonia or Proteus vulgaris. The results of this study support our hypothesis and suggest that the screen used is sufficient and appropriate to detect secreted antibacterial fungal compounds resulting from mutagenesis of A. oryzae. Because the genome of A. oryzae has been sequenced and systems are available for genetic transformation of this organism, targeted as well as random mutations may be introduced to facilitate the discovery of novel antibacterial compounds using this system.

  17. Assessment of genetic diversity of Xanthomonas oryzae pv. oryzae

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@Bacterial blight of rice, caused by Xanthomonas oryzae pv. Oryzae(Xoo. ), is one of the major rice diseases in China. Making clear the shift of genetic diversity of the pathogen will provide important information for rice breeding. Strains collected from 11 provinces located in Southern region of the Changjiang River in China were assessed by using inoculation method and IS-PCR(Insertion Sequence-Based Polymerase Chain Reaction) analysis.

  18. Morphological characterization of recombinant strains of Aspergillus oryzae producing alpha-amylase during batch cultivations

    DEFF Research Database (Denmark)

    Spohr, Anders Bendsen; Carlsen, Morten; Nielsen, Jens Bredal

    1997-01-01

    Three alpha-amylase producing strains of Aspergillus oryzae used for recombinant protein production have been studied with respect to growth and protein production. By comparing the three strains with respect to morphology and protein production it is shown that a morphological mutant with a more...

  19. Molecular detection of Xanthomonas oryzae pv. oryzae, Xanthomonas oryzae pv. oryzicola, and Burkholderia glumae in infected rice seeds and leaves

    Science.gov (United States)

    Polymerase chain reaction (PCR) is particularly useful for plant pathogen detection. In the present study, multiplex PCR and SYBR green real-time PCR were developed to facilitate simultaneous detection of three important rice pathogens, Xanthomonas oryzae pv. oryzae, X. oryzae pv. oryzicola, and Bur...

  20. Characterization of two thermostable inulinases from Rhizopus oligosporus NRRL 2710

    Directory of Open Access Journals (Sweden)

    Saleh A. Mohamed

    2015-06-01

    Full Text Available Two inulinases (Inu2 and Inu3 were purified from Rhizopus oligosporus NRRL 2710 by chromatography on DEAE-Sepharose and Sephacryl S-200 columns. The molecular weight of Inu2 and Inu3 were determined to be 76 and 30 kDa, respectively. Inu2 and Inu3 had the same pH optimum at 5.0, temperature optimum at 50 and 60 °C, and thermal stability up to 60 and 70 °C for 1 h, respectively. Inu2 and Inu3 had low km values (0.93 and 0.70 mM, respectively indicating the high affinity toward inulin. Mg2+, Ca2+, Zn2+ and EDTA did not significantly influence the enzyme activity. Ni2+, Cu2+, Fe2+ and Co2+ showed a partial inhibitory effect, and Hg2+ had a strong inhibitory effect. p-Chloromercuribenzoate had a partial inhibitory effect on Inu2. From these findings, R. oligosporus inulinases can be beneficial enzymes for industrial enzymatic production of high fructose syrup.

  1. Karakterisasi ekstrak kasar lipase Rhizopus stolonifer UICC 137

    Directory of Open Access Journals (Sweden)

    Sri Sumiarsih

    2001-12-01

    Full Text Available There is an increasing commercial interest in enzymatic production of biologically active component, because there are a number of well-known advantages compared to chemical synthesis. One of the most valuable synthetic features of enzyme is their ability to discriminate between enantiomers of racemic substrates. Lipase have become of great interest to the chemical industries wing their usefulness in both hydrolytic and synthesis reactions. The aim of this work was to study the production of lipase by Rhizopus stolonifer UICC 137, and determine the crude lipase preparation characteristics. The lipolytic activity was determined by titrimetric method toward oil-arabic gum emultion as a substrate. The strain produced lipase at appreciable lipolytic when cultivated for 72 hours in medium containing 3% glucose and 1% olive oil. Our data suggest that the strain produced lipase since the exponential phase of its growth. Lipase with optimum lipolytic activity was obtained at late stationary phase. The optimum condition for lipolytic activity measurement were pH of 7.5 and temperature 37oC, the crude enzyme had a specific activity 20.2 unit/ mg protein, the Vmax was 15.1 mol/ min and KM was 12.5 mg/ ml. The crude enzyme retained 79.9%, 68.0% and 52.6% of its lipolytic activity, when incubated for 90 minutes at temperature of 40, 50, and 60oC respectively.

  2. Biosorption of americium-241 by immobilized Rhizopus arrihizus

    International Nuclear Information System (INIS)

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

    2004-01-01

    Rhizopus arrihizus (R. arrihizus), a fungus, which in previous experiments had shown encouraging ability to remove 241 Am from solutions, was immobilized by calcium alginate and other reagents. The various factors affecting 241 Am biosorption by the immobilized R. arrihizus were investigated. The results showed that not only can immobilized R. arrihizus adsorb 241 Am as efficiently as free R. arrihizus, but that also can be used repeatedly or continuously. The biosorption equilibrium was achieved within 2 h, and more than 94% of 241 Am was removed from 241 Am solutions of 1.08 MBq/l by immobilized R. arrihizu in the pH range 1-7. Temperature did not affect the adsorption on immobilized R. arrihizus in the range 15-45 deg. C. After repeated adsorption for 8 times, the immobilized R. arrihizus still adsorbed more than 97% of 241 Am. At this time, the total adsorption of 241 Am was more than 88.6 KBq/g, and had not yet reached saturation. Ninety-five percent of the adsorbed 241 Am was desorbed by saturated EDTA solution and 98% by 2 mol/l HNO 3

  3. Identification and analysis of Ku70 and Ku80 homologs in the koji molds Aspergillus sojae and Aspergillus oryzae.

    Science.gov (United States)

    Takahashi, Tadashi; Masuda, Tsutomu; Koyama, Yasuji

    2006-01-01

    Ku genes play a key role in the non-homologous end-joining pathway. We have identified Ku70 and Ku80 homologs in the koji molds Aspergillus sojae and Aspergillus oryzae, and have constructed the disruption mutants of Ku70, Ku80, and Ku70-80 to characterize the phenotypic change in these mutants. Neither Ku70- nor Ku80-disrupted strains show hypersensitivity to the DNA damaging agents methylmethane sulfonate (MMS) and phleomycin. Moreover, undesirable phenotypes, such as poor growth or repressed conidiospore formation, were not observed in the Ku-disrupted A. sojae and A. oryzae.

  4. Production of oat-based synbiotic beverage by two-stage fermentation with Rhizopus oryzae and Lactobacillus acidophilus

    NARCIS (Netherlands)

    Gao, F.; Cai, S.; Nout, M.J.R.; Wang, Y.; Xia, Y.; Li, Y.; Ji, B.

    2012-01-01

    Many studies have reported that oats could effectively reduce the serum cholesterol levels in humans, and the ß-glucan in oat is believed to be responsible for this physiologic effect. Probiotics are live microorganisms that can confer a healthy benefit on the host when administered in adequate

  5. Genetic variation and population structure in Oryza ...

    Indian Academy of Sciences (India)

    Oryza malampuzhaensis Krish. et Chand. ( 2 n = 4 x = 48 ; Poaceae, Oryza) is endemic to Western Ghats, South India, and shows a highly localized distribution over a small geographical area in this region. This is the most poorly understood taxon in genus Oryza and is often misidentified as O. officinalis owing to their close ...

  6. Effect of Meadowsweet Flower Extract-Pullulan Coatings on Rhizopus Rot Development and Postharvest Quality of Cold-Stored Red Peppers

    Directory of Open Access Journals (Sweden)

    Alicja Synowiec

    2014-08-01

    Full Text Available The study involved an examination of the antifungal activity on red peppers of pullulan coating (P and pullulan coating containing either water-ethanol (P + eEMF or ethanol extract of meadowsweet flowers (P + eEMF. Pullulan was obtained from a culture of Aureobasidium pullulans B-1 mutant. Both non-inoculated peppers and those artificially inoculated with Rhizopus arrhizus were coated and incubated at 24 °C for 5 days. The intensity of the decay caused by Rhizopus arrhizus in the peppers with P and P + eEMF coatings was nearly 3-fold lower, and in the case of P + weEMF 5-fold lower, than that observed in the control peppers. Additionally, the P + weEMF coating decreased, almost two-fold the severity of pepper decay compared to other samples. The influence of coating of pepper postharvest quality was examined after 30 days of storage at 6 °C and 70%–75% RH. All coatings formed a thin and well-attached additional layer of an intensified gloss. During storage, color, total soluble solid content and weight loss of coated peppers were subject to lower changes in comparison with uncoated ones. The results indicate the possibility of the application of pullulan coatings containing MFEs as an alternative to the chemical fungicides used to combat pepper postharvest diseases.

  7. OryzaGenome: Genome Diversity Database of Wild Oryza Species

    KAUST Repository

    Ohyanagi, Hajime

    2015-11-18

    The species in the genus Oryza, encompassing nine genome types and 23 species, are a rich genetic resource and may have applications in deeper genomic analyses aiming to understand the evolution of plant genomes. With the advancement of next-generation sequencing (NGS) technology, a flood of Oryza species reference genomes and genomic variation information has become available in recent years. This genomic information, combined with the comprehensive phenotypic information that we are accumulating in our Oryzabase, can serve as an excellent genotype-phenotype association resource for analyzing rice functional and structural evolution, and the associated diversity of the Oryza genus. Here we integrate our previous and future phenotypic/habitat information and newly determined genotype information into a united repository, named OryzaGenome, providing the variant information with hyperlinks to Oryzabase. The current version of OryzaGenome includes genotype information of 446 O. rufipogon accessions derived by imputation and of 17 accessions derived by imputation-free deep sequencing. Two variant viewers are implemented: SNP Viewer as a conventional genome browser interface and Variant Table as a textbased browser for precise inspection of each variant one by one. Portable VCF (variant call format) file or tabdelimited file download is also available. Following these SNP (single nucleotide polymorphism) data, reference pseudomolecules/ scaffolds/contigs and genome-wide variation information for almost all of the closely and distantly related wild Oryza species from the NIG Wild Rice Collection will be available in future releases. All of the resources can be accessed through http://viewer.shigen.info/oryzagenome/.

  8. Extracellular biosynthesis of silver nanoparticles using Rhizopus stolonifer

    Directory of Open Access Journals (Sweden)

    Khalid AbdelRahim

    2017-01-01

    Full Text Available Synthesis of silver nanoparticles (AgNPs has become a necessary field of applied science. Biological method for synthesis of AgNPs by Rhizopus stolonifer aqueous mycelial extract was used. The AgNPs were identified by UV–visible spectrometry, X-ray diffraction (XRD, transmission electron microscopy (TEM and Fourier transform infrared spectrometry (FT-IR. The presence of surface plasmon band around 420 nm indicates AgNPs formation. The characteristic of the AgNPs within the face-centered cubic (fcc structure are indicated by the peaks of the X-ray diffraction (XRD pattern corresponding to (111, (200 and (220 planes. Spherical, mono-dispersed and stable AgNPs with diameter around 9.47 nm were prepared and affirmed by high-resolution transmission electron microscopy (HR-TEM. Fourier Transform Infrared (FTIR shows peaks at 1426 and 1684 cm−1 that affirm the presence of coat covering protein the AgNPs which is known as capping proteins. Parameter optimization showed the smallest size of AgNPs (2.86 ± 0.3 nm was obtained with 10−2 M AgNO3 at 40 °C. The present study provides the proof that the molecules within aqueous mycelial extract of R. stolonifer facilitate synthesis of AgNPs and highlight on value-added from R. stolonifer for cost effectiveness. Also, eco-friendly medical and nanotechnology-based industries could also be provided. Size of prepared AgNPs could be controlled by temperature and AgNO3 concentration. Further studies are required to study effect of more parameters on size and morphology of AgNPs as this will help in the control of large scale production of biogenic AgNPs.

  9. Genome Sequences of Oryza Species

    KAUST Repository

    Kumagai, Masahiko; Tanaka, Tsuyoshi; Ohyanagi, Hajime; Hsing, Yue-Ie C.; Itoh, Takeshi

    2018-01-01

    This chapter summarizes recent data obtained from genome sequencing, annotation projects, and studies on the genome diversity of Oryza sativa and related Oryza species. O. sativa, commonly known as Asian rice, is the first monocot species whose complete genome sequence was deciphered based on physical mapping by an international collaborative effort. This genome, along with its accurate and comprehensive annotation, has become an indispensable foundation for crop genomics and breeding. With the development of innovative sequencing technologies, genomic studies of O. sativa have dramatically increased; in particular, a large number of cultivars and wild accessions have been sequenced and compared with the reference rice genome. Since de novo genome sequencing has become cost-effective, the genome of African cultivated rice, O. glaberrima, has also been determined. Comparative genomic studies have highlighted the independent domestication processes of different rice species, but it also turned out that Asian and African rice share a common gene set that has experienced similar artificial selection. An international project aimed at constructing reference genomes and examining the genome diversity of wild Oryza species is currently underway, and the genomes of some species are publicly available. This project provides a platform for investigations such as the evolution, development, polyploidization, and improvement of crops. Studies on the genomic diversity of Oryza species, including wild species, should provide new insights to solve the problem of growing food demands in the face of rapid climatic changes.

  10. Genome Sequences of Oryza Species

    KAUST Repository

    Kumagai, Masahiko

    2018-02-14

    This chapter summarizes recent data obtained from genome sequencing, annotation projects, and studies on the genome diversity of Oryza sativa and related Oryza species. O. sativa, commonly known as Asian rice, is the first monocot species whose complete genome sequence was deciphered based on physical mapping by an international collaborative effort. This genome, along with its accurate and comprehensive annotation, has become an indispensable foundation for crop genomics and breeding. With the development of innovative sequencing technologies, genomic studies of O. sativa have dramatically increased; in particular, a large number of cultivars and wild accessions have been sequenced and compared with the reference rice genome. Since de novo genome sequencing has become cost-effective, the genome of African cultivated rice, O. glaberrima, has also been determined. Comparative genomic studies have highlighted the independent domestication processes of different rice species, but it also turned out that Asian and African rice share a common gene set that has experienced similar artificial selection. An international project aimed at constructing reference genomes and examining the genome diversity of wild Oryza species is currently underway, and the genomes of some species are publicly available. This project provides a platform for investigations such as the evolution, development, polyploidization, and improvement of crops. Studies on the genomic diversity of Oryza species, including wild species, should provide new insights to solve the problem of growing food demands in the face of rapid climatic changes.

  11. Deletion of creB in Aspergillus oryzae increases secreted hydrolytic enzyme activity.

    Science.gov (United States)

    Hunter, A J; Morris, T A; Jin, B; Saint, C P; Kelly, J M

    2013-09-01

    Aspergillus oryzae has been used in the food and beverage industry for centuries, and industrial strains have been produced by multiple rounds of selection. Targeted gene deletion technology is particularly useful for strain improvement in such strains, particularly when they do not have a well-characterized meiotic cycle. Phenotypes of an Aspergillus nidulans strain null for the CreB deubiquitinating enzyme include effects on growth and repression, including increased activity levels of various enzymes. We show that Aspergillus oryzae contains a functional homologue of the CreB deubiquitinating enzyme and that a null strain shows increased activity levels of industrially important secreted enzymes, including cellulases, xylanases, amylases, and proteases, as well as alleviated inhibition of spore germination on glucose medium. Reverse transcription-quantitative PCR (RT-qPCR) analysis showed that the increased levels of enzyme activity in both Aspergillus nidulans and Aspergillus oryzae are mirrored at the transcript level, indicating transcriptional regulation. We report that Aspergillus oryzae DAR3699, originally isolated from soy fermentation, has a similar phenotype to that of a creB deletion mutant of the RIB40 strain, and it contains a mutation in the creB gene. Collectively, the results for Aspergillus oryzae, Aspergillus nidulans, Trichoderma reesei, and Penicillium decumbens show that deletion of creB may be broadly useful in diverse fungi for increasing production of a variety of enzymes.

  12. Evaluation of Rhizopus oligosporus in nursery pig diets on growth performance and nutrient digestibility

    Science.gov (United States)

    The thin stillage leftover from ethanol production contains biodegradable organic compounds and sufficient micronutrients that are ideal for fungal cultivation of Rhizopus oligosporus (RO). This fungus removes about 60% of the organic material, including the suspended solids and even more of some sp...

  13. Rheology, microstructure and baking characteristics of frozen dough containing Rhizopus chinensis lipase and transglutaminase

    Science.gov (United States)

    The beneficial effects of a new recombinant lipase (Rhizopus chinensis lipase, RCL) and transglutaminase (TG) were investigated on frozen dough systems and their breadmaking quality. Rheological properties and microstructure of doughs were measured using a dynamic rheometer, rheofermentometer F3, an...

  14. FERMENTASI BUNGKIL KOPRA DENGAN Rhizopus sp. DAN PEMANFAATANNYA DALAM PAKAN PEMBESARAN IKAN BANDENG DI TAMBAK

    Directory of Open Access Journals (Sweden)

    Usman Usman

    2014-12-01

    Full Text Available Bungkil kopra (BK hasil fermentasi dengan Rhizopus sp. memiliki kandungan protein yang lebih tinggi dan lemak yang lebih rendah dibandingkan yang tidak difermentasi, sehingga memiliki potensi dan perlu dimanfaatkan sebagai sumber protein dalam pakan ikan-ikan herbivora-omnivora seperti ikan bandeng. Penelitian ini bertujuan mengamati pemanfaatan bungkil kopra hasil fermentasi dengan Rhizopus sp. sebagai sumber protein dalam pakan untuk pembesaran ikan bandeng di tambak. Penelitian dilakukan dengan menggunakan empat petak tambak masing-masing berukuran 2.500 m2/petak. Ikan uji yang digunakan adalah yuwana ikan bandeng berukuran awal rata-rata 10 g/ekor yang ditebar dengan kepadatan 1.500 ekor/petak, dan diaplikasikan pakan uji pada saat ikan berukuran rata-rata 65 g. Pakan uji yang digunakan adalah pakan buatan yang berbahan baku utama (A tepung bungkil kopra tanpa fermentasi, dan (B tepung bungkil kopra hasil fermentasi dengan Rhizopus sp. Hasil penelitian menunjukkan bahwa laju pertumbuhan spesifik ikan, rasio konversi pakan, dan sintasan ikan tidak berbeda nyata (P>0,05 di antara kedua perlakuan. Namun ikan yang diberi pakan uji B memiliki produksi yang lebih tinggi (P<0,05 daripada yang diberi pakan uji A. Bungkil kopra yang difermentasi dengan Rhizopus sp. dapat dimanfaatkan sebagai sumber protein dalam pakan ikan bandeng.

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

    Science.gov (United States)

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

    2013-01-01

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

  16. Selección preliminar de plantas de arroz con resistencia vertical A pyricularia oryzae Cav por inducción de mutaciones (ING

    Directory of Open Access Journals (Sweden)

    A Cruz

    2016-03-01

    Full Text Available Seeds of rice Oryza sativa L. cv. CR-1113 susceptible to blast disease Pyricularia oryzae Cav. Were subjected to gamma radiation with 60Co using doses of 15 and 20 krads to obtain and select mutant plants with vertical resistance to blast. A total of 80.000 rice plants per treatment were individually evaluated in the second mutant generation (M2 at tillering and panicle emergence. Vertical resistance was observed in 47 and 8 plants from the 15 and 20 krads treatments respectively.

  17. Lethal and mutagenic effects of ion beams and γ-rays in Aspergillus oryzae

    International Nuclear Information System (INIS)

    Toyoshima, Yoshiyuki; Takahashi, Akemi; Tanaka, Hisaki; Watanabe, Jun; Mogi, Yoshinobu; Yamazaki, Tatsuo; Hamada, Ryoko; Iwashita, Kazuhiro; Satoh, Katsuya; Narumi, Issay

    2012-01-01

    Highlights: ► We investigated the effects of different LET radiation in A. oryzae. ► Both γ-rays and ion beams induced base substitutions, frameshifts, deletions. ► Both γ-rays and ion beams induced genome-wide large-scale mutations in A. oryzae. ► Some differences in the types and frequencies of mutations were found. ► Our results provide new basic insights into the mutation breeding of A. oryzae. - Abstract: Aspergillus oryzae is a fungus that is used widely in traditional Japanese fermentation industries. In this study, the lethal and mutagenic effects of different linear energy transfer (LET) radiation in freeze-dried conidia of A. oryzae were investigated. The lethal effect, which was evaluated by a 90% lethal dose, was dependent on the LET value of the ionizing radiation. The most lethal ionizing radiation among that tested was 12 C 5+ ion beams with an LET of 121 keV/μm. The 12 C 5+ ion beams had a 3.6-times higher lethal effect than low-LET (0.2 keV/μm) γ-rays. The mutagenic effect was evaluated by the frequency of selenate resistant mutants. 12 C 6+ ion beams with an LET of 86 keV/μm were the most effective in inducing selenate resistance. The mutant frequency following exposure to 12 C 6+ ion beams increased with an increase in dose and reached 3.47 × 10 −3 at 700 Gy. In the dose range from 0 to 700 Gy, 12 C 5+ ion beams were the second most effective in inducing selenate resistance, the mutant frequency of which reached a maximum peak (1.67 × 10 −3 ) at 400 Gy. To elucidate the characteristics of mutation induced by ionizing radiation, mutations in the sulphate permease gene (sB) and ATP sulfurylase gene (sC) loci, the loss of function of which results in a selenate resistant phenotype, were compared between 12 C 5+ ion beams and γ-rays. We detected all types of transversions and transitions. For frameshifts, the frequency of a +1 frameshift was the highest in all cases. Although the incidence of deletions >2 bp was generally low

  18. The changeability of Pyricularia oryzae Cav. 1. The action of some mutagenous factors

    International Nuclear Information System (INIS)

    Voinova, T.M.; Terekhova, V.A.; D'yakov, Yu.T.

    1983-01-01

    The lethal and mutagenous actions of UV rays, nitrozomethylurea, and nitrosoguanidine in respect to Conidia of rice Pyricularia oryzae Cav. agent have been investigated. It has been found out that low doses of UV-radiation, which are not lethal for a three-cell conidia, increase the intensity of two-cell vegetation. All the investigated mutagens cause a formation of mutants which are deficient according to pigment synthesis white and pink colonies and differ by their reduced growth. Auxotrophic mutants were mainly obtained under the action of nitroso compounds

  19. Fungi and some mycotoxins contaminating rice ( Oryza Sativa ) in ...

    African Journals Online (AJOL)

    The major fungal genera contaminating rice were Aspergillus, Penicillium, Fusarium, Alternaria, Mucor, Rhizopus, Trichoderma, Curvularia, elminthosporium and Cladosporium. The most prevalent fungal species on rice were .Penicillium spp., A. flavus, A. parasiticus, A. niger, Mucor spp., Rhizopus spp. and Alternaria spp.

  20. Increased metabolite production by deletion of an HDA1-type histone deacetylase in the phytopathogenic fungi, Magnaporthe oryzae (Pyricularia oryzae) and Fusarium asiaticum.

    Science.gov (United States)

    Maeda, K; Izawa, M; Nakajima, Y; Jin, Q; Hirose, T; Nakamura, T; Koshino, H; Kanamaru, K; Ohsato, S; Kamakura, T; Kobayashi, T; Yoshida, M; Kimura, M

    2017-11-01

    Histone deacetylases (HDACs) play an important role in the regulation of chromatin structure and gene expression. We found that dark pigmentation of Magnaporthe oryzae (anamorph Pyricularia oryzae) ΔMohda1, a mutant strain in which an orthologue of the yeast HDA1 was disrupted by double cross-over homologous recombination, was significantly stimulated in liquid culture. Analysis of metabolites in a ΔMohda1 mutant culture revealed that the accumulation of shunt products of the 1,8-dihydroxynaphthalene melanin and ergosterol pathways were significantly enhanced compared to the wild-type strain. Northern blot analysis of the ΔMohda1 mutant revealed transcriptional activation of three melanin genes that are dispersed throughout the genome of M. oryzae. The effect of deletion of the yeast HDA1 orthologue was also observed in Fusarium asiaticum from the Fusarium graminearum species complex; the HDF2 deletion mutant produced increased levels of nivalenol-type trichothecenes. These results suggest that histone modification via HDA1-type HDAC regulates the production of natural products in filamentous fungi. Natural products of fungi have significant impacts on human welfare, in both detrimental and beneficial ways. Although HDA1-type histone deacetylase is not essential for vegetative growth, deletion of the gene affects the expression of clustered secondary metabolite genes in some fungi. Here, we report that such phenomena are also observed in physically unlinked genes required for melanin biosynthesis in the rice blast fungus. In addition, production of Fusarium trichothecenes, previously reported to be unaffected by HDA1 deletion, was significantly upregulated in another Fusarium species. Thus, the HDA1-inactivation strategy may be regarded as a general approach for overproduction and/or discovery of fungal metabolites. © 2017 The Society for Applied Microbiology.

  1. Self-induction system for cellulase production by cellobiose produced from glucose in Rhizopus stolonifer

    OpenAIRE

    Zhang, Yingying; Tang, Bin; Du, Guocheng

    2017-01-01

    Cellulolytic fungi have evolved a sophisticated genetic regulatory network of cellulase synthesis to adapt to the natural environment. Even in the absence of lignocellulose, it still secretes low levels of ?constitutive? cellulase for standby application. However, the mechanisms of this constitutive expression remain incompletely understood. Here we identified a cellobiose synthetase (CBS) from Rhizopus stolonifer, which has the capacity to catalyse the synthesis of cellobiose from uridine di...

  2. Differentiation of clinically relevant Mucorales Rhizopus microsporus and R. arrhizus by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS).

    Science.gov (United States)

    Dolatabadi, Somayeh; Kolecka, Anna; Versteeg, Matthijs; de Hoog, Sybren G; Boekhout, Teun

    2015-07-01

    This study addresses the usefulness of matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) MS for reliable identification of the two most frequently occurring clinical species of Rhizopus, namely Rhizopus arrhizus with its two varieties, arrhizus and delemar, and Rhizopus microsporus. The test-set comprised 38 isolates of clinical and environmental origin previously identified by internal transcribed spacer (ITS) sequencing of rDNA. Multi-locus sequence data targeting three gene markers (ITS, ACT, TEF ) showed two monophylic clades for Rhizopus arrhizus and Rhizopus microsporus (bootstrap values of 99 %). Cluster analysis confirmed the presence of two distinct clades within Rhizopus arrhizus representing its varieties arrhizus and delemar. The MALDI Biotyper 3.0 Microflex LT platform (Bruker Daltonics) was used to confirm the distinction between Rhizopus arrhizus and Rhizopus microsporus and the presence of two varieties within the species Rhizopus arrhizus. An in-house database of 30 reference main spectra (MSPs) was initially tested for correctness using commercially available databases of Bruker Daltonics. By challenging the database with the same strains of which an in-house database was created, automatic identification runs confirmed that MALDI-TOF MS is able to recognize the strains at the variety level. Based on principal component analysis, two MSP dendrograms were created and showed concordance with the multi-locus tree; thus, MALDI-TOF MS is a useful tool for diagnostics of mucoralean species.

  3. HrcQ is necessary for Xanthomonas oryzae pv. oryzae HR-induction in non-host tobacco and pathogenicity in host rice

    Directory of Open Access Journals (Sweden)

    Xiaoping Zhang

    2013-12-01

    Full Text Available Bacterial blight, caused by Xanthomonas oryzae pv. oryzae (Xoo, is one of the most destructive diseases of rice (Oryza sativa L. worldwide. The type III secretion system (T3SS of Xoo, encoded by the hrp (hypersensitive response and pathogenicity genes, plays critical roles in conferring pathogenicity in host rice and triggering a hypersensitive response (HR in non-host plants. To investigate the major genes conferring the pathogenicity and avirulence of Xoo, we previously constructed a random Tn5-insertion mutant library of Xoo strain PXO99A. We report here the isolation and characterization of a Tn5-insertion mutant PXM69. Tn5-insertion mutants were screened on indica rice JG30, which is highly susceptible to PXO99A, by leaf-cutting inoculation. Four mutants with reduced virulence were obtained after two rounds of screening. Among them, the mutant PXM69 had completely lost virulence to the rice host and ability to elicit HR in non-host tobacco. Southern blotting analysis showed a single copy of a Tn5-insertion in the genome of PXM69. PCR walking and sequencing analysis revealed that the Tn5 transposon was inserted at nucleotide position 70,192–70,201 in the genome of PXO99A, disrupting the type III hrc (hrp-conserved gene hrcQ, the first gene in the D operon of the hrp cluster in Xoo. To confirm the relationship between the Tn5-insertion and the avirulence phenotype of PXM69, we used the marker exchange mutagenesis to create a PXO99A mutant, ΔhrcQ::KAN, in which the hrcQ was disrupted by a kanamycin-encoding gene cassette at the same site as that of the Tn5-insertion. ΔhrcQ::KAN showed the same phenotype as mutant PXM69. Reintroduction of the wild-type hrcQ gene partially complemented the pathogenic function of PXM69. RT-PCR and cellulase secretion assays showed that the Tn5-disruption of hrcQ did not affect transcription of downstream genes in the D operon and function of the type II secretion system. Our results provide new insights into

  4. Increased production of biomass-degrading enzymes by double deletion of creA and creB genes involved in carbon catabolite repression in Aspergillus oryzae.

    Science.gov (United States)

    Ichinose, Sakurako; Tanaka, Mizuki; Shintani, Takahiro; Gomi, Katsuya

    2018-02-01

    In a previous study, we reported that a double gene deletion mutant for CreA and CreB, which constitute the regulatory machinery involved in carbon catabolite repression, exhibited improved production of α-amylase compared with the wild-type strain and single creA or creB deletion mutants in Aspergillus oryzae. Because A. oryzae can also produce biomass-degrading enzymes, such as xylolytic and cellulolytic enzymes, we examined the production levels of those enzymes in deletion mutants in this study. Xylanase and β-glucosidase activities in the wild-type were hardly detected in submerged culture containing xylose as the carbon source, whereas those enzyme activities were significantly increased in the single creA deletion (ΔcreA) and double creA and creB deletion (ΔcreAΔcreB) mutants. In particular, the ΔcreAΔcreB mutant exhibited >100-fold higher xylanase and β-glucosidase activities than the wild-type. Moreover, in solid-state culture, the β-glucosidase activity of the double deletion mutant was >7-fold higher than in the wild-type. These results suggested that deletion of both creA and creB genes could also efficiently improve the production levels of biomass-degrading enzymes in A. oryzae. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  5. HrcQ is necessary for Xanthomonas oryzae pv. oryzae HR-induction in non-host tobacco and pathogenicity in host rice

    Institute of Scientific and Technical Information of China (English)

    Xiaoping; Zhang; Chunlian; Wang; Chongke; Zheng; Jinying; Che; Yanqiang; Li; Kaijun; Zhao

    2013-01-01

    Bacterial blight, caused by Xanthomonas oryzae pv. oryzae(Xoo), is one of the most destructive diseases of rice(Oryza sativa L.) worldwide. The type III secretion system(T3SS) of Xoo, encoded by the hrp(hypersensitive response and pathogenicity) genes, plays critical roles in conferring pathogenicity in host rice and triggering a hypersensitive response(HR) in non-host plants. To investigate the major genes conferring the pathogenicity and avirulence of Xoo, we previously constructed a random Tn5-insertion mutant library of Xoo strain PXO99A. We report here the isolation and characterization of a Tn5-insertion mutant PXM69. Tn5-insertion mutants were screened on indica rice JG30, which is highly susceptible to PXO99A, by leaf-cutting inoculation.Four mutants with reduced virulence were obtained after two rounds of screening. Among them, the mutant PXM69 had completely lost virulence to the rice host and ability to elicit HR in non-host tobacco. Southern blotting analysis showed a single copy of a Tn5-insertion in the genome of PXM69. PCR walking and sequencing analysis revealed that the Tn5 transposon was inserted at nucleotide position 70,192–70,201 in the genome of PXO99A, disrupting the type III hrc(hrp-conserved) gene hrcQ, the first gene in the D operon of the hrp cluster in Xoo. To confirm the relationship between the Tn5-insertion and the avirulence phenotype of PXM69, we used the marker exchange mutagenesis to create a PXO99Amutant, ΔhrcQ::KAN, in which the hrcQ was disrupted by a kanamycin-encoding gene cassette at the same site as that of the Tn5-insertion. ΔhrcQ::KAN showed the same phenotype as mutant PXM69. Reintroduction of the wild-type hrcQ gene partially complemented the pathogenic function of PXM69. RT-PCR and cellulase secretion assays showed that the Tn5-disruption of hrcQ did not affect transcription of downstream genes in the D operon and function of the type II secretion system. Our results provide new insights into the pathogenic

  6. Evaluation of Oryza sativa x O. glaberrima derived progenies for ...

    African Journals Online (AJOL)

    USER

    2010-06-28

    Jun 28, 2010 ... The genus Oryza has two cultivated species, Asian rice (Oryza sativa L.) and African rice (Oryza glaberrima Steud.) and 22 wild species. O. glaberrima is low yielding but has useful genes for resistance to biotic and abiotic stresses. Introgression lines derived from backcrossing of O. sativa x O. glaberrima,.

  7. Oryza sativa Chloroplast Signal Recognition Particle 43 (OscpSRP43 Is Required for Chloroplast Development and Photosynthesis.

    Directory of Open Access Journals (Sweden)

    Xiang-guang Lv

    Full Text Available A rice chlorophyll-deficient mutant w67 was isolated from an ethyl methane sulfonate (EMS-induced IR64 (Oryza sativa L. ssp. indica mutant bank. The mutant exhibited a distinct yellow-green leaf phenotype in the whole plant growth duration with significantly reduced levels of chlorophyll and carotenoid, impaired chloroplast development and lowered capacity of photosynthesis compared with the wild-type IR64. Expression of a number of genes associated with chlorophyll metabolism, chloroplast biogenesis and photosynthesis was significantly altered in the mutant. Genetic analysis indicated that the yellow-green phenotype was controlled by a single recessive nuclear gene located on the short arm of chromosome 3. Using map-based strategy, the mutation was isolated and predicted to encode a chloroplast signal recognition particle 43 KD protein (cpSRP43 with 388 amino acid residuals. A single base substitution from A to T at position 160 resulted in a premature stop codon. OscpSRP43 was constitutively expressed in various organs with the highest level in the leaf. Functional complementation could rescue the mutant phenotype and subcellular localization showed that the cpSRP43:GFP fusion protein was targeted to the chloroplast. The data suggested that Oryza sativa cpSRP43 (OscpSRP43 was required for the normal development of chloroplasts and photosynthesis in rice.

  8. Biosorption of Acid Blue 290 (AB 290) and Acid Blue 324 (AB 324) dyes on Spirogyra rhizopus

    International Nuclear Information System (INIS)

    Ozer, Ayla; Akkaya, Goenuel; Turabik, Meral

    2006-01-01

    In this study, the biosorption of Acid Blue 290 and Acid Blue 324 on Spirogyra rhizopus, a green algae growing on fresh water, was studied with respect to initial pH, temperature, initial dye concentration and biosorbent concentration. The optimum initial pH and temperature values for AB 290 and AB 324 biosorption were found to be 2.0, 30 deg. C and 3.0, 25 deg. C, respectively. It was observed that the adsorbed AB 290 and AB 324 amounts increased with increasing the initial dye concentration up to 1500 and 750 mg/L, respectively. The Langmuir, Freundlich, Redlich-Peterson and Koble-Corrigan isotherm models were applied to the experimental equilibrium data and the isotherm constants were determined by using Polymath 4.1 software. The monolayer coverage capacities of S. rhizopus for AB 290 and AB 324 dyes were found as 1356.6 mg/g and 367.0 mg/g, respectively. The intraparticle diffusion model and the pseudo-second order kinetic model were applied to the experimental data in order to describe the removal mechanism of these acidic dyes by S. rhizopus. The pseudo-second order kinetic model described very well the biosorption kinetics of AB 290 and AB 324 dyes. Thermodynamic studies showed that the biosorption of AB 290 and AB 324 on S. rhizopus was exothermic in nature

  9. Comparative proteomics of Rhizopus delemar ATCC 20344 unravels the role of amino acid catabolism in fumarate accumulation

    NARCIS (Netherlands)

    Odoni, Dorett I.; Tamayo-Ramos, Juan A.; Sloothaak, Jasper; Heck, van Ruben; Martins dos Santos, Vitor A.P.; Graaff, de Leo H.; Suarez-Diez, Maria; Schaap, Peter J.

    2017-01-01

    The filamentous fungus Rhizopus delemar naturally accumulates relatively high amounts of fumarate. Although the culture conditions that increase fumarate yields are well established, the network underlying the accumulation of fumarate is not yet fully understood. We set out to increase the

  10. Cellular responses to the expression of unstable secretory proteins in the filamentous fungus Aspergillus oryzae.

    Science.gov (United States)

    Yokota, Jun-Ichi; Shiro, Daisuke; Tanaka, Mizuki; Onozaki, Yasumichi; Mizutani, Osamu; Kakizono, Dararat; Ichinose, Sakurako; Shintani, Tomoko; Gomi, Katsuya; Shintani, Takahiro

    2017-03-01

    Filamentous fungi are often used as cell factories for recombinant protein production because of their ability to secrete large quantities of hydrolytic enzymes. However, even using strong transcriptional promoters, yields of nonfungal proteins are generally much lower than those of fungal proteins. Recent analyses revealed that expression of certain nonfungal secretory proteins induced the unfolded protein response (UPR), suggesting that they are recognized as proteins with folding defects in filamentous fungi. More recently, however, even highly expressed endogenous secretory proteins were found to evoke the UPR. These findings raise the question of whether the unfolded or misfolded state of proteins is selectively recognized by quality control mechanisms in filamentous fungi. In this study, a fungal secretory protein (1,2-α-D-mannosidase; MsdS) with a mutation that decreases its thermostability was expressed at different levels in Aspergillus oryzae. We found that, at moderate expression levels, wild-type MsdS was secreted to the medium, while the mutant was not. In the strain with a deletion for the hrdA gene, which is involved in the endoplasmic reticulum-associated degradation pathway, mutant MsdS had specifically increased levels in the intracellular fraction but was not secreted. When overexpressed, the mutant protein was secreted to the medium to a similar extent as the wild-type protein; however, the mutant underwent hyperglycosylation and induced the UPR. Deletion of α-amylase (the most abundant secretory protein in A. oryzae) alleviated the UPR induction by mutant MsdS overexpression. These findings suggest that misfolded MsdS and unfolded species of α-amylase might act synergistically for UPR induction.

  11. Unfolded protein response is required for Aspergillus oryzae growth under conditions inducing secretory hydrolytic enzyme production.

    Science.gov (United States)

    Tanaka, Mizuki; Shintani, Takahiro; Gomi, Katsuya

    2015-12-01

    Unfolded protein response (UPR) is an intracellular signaling pathway for adaptation to endoplasmic reticulum (ER) stress. In yeast UPR, Ire1 cleaves the unconventional intron of HAC1 mRNA, and the functional Hac1 protein translated from the spliced HAC1 mRNA induces the expression of ER chaperone genes and ER-associated degradation genes for the refolding or degradation of unfolded proteins. In this study, we constructed an ireA (IRE1 ortholog) conditionally expressing strain of Aspergillus oryzae, a filamentous fungus producing a large amount of amylolytic enzymes, and examined the contribution of UPR to ER stress adaptation under physiological conditions. Repression of ireA completely blocked A. oryzae growth under conditions inducing the production of hydrolytic enzymes, such as amylases and proteases. This growth defect was restored by the introduction of unconventional intronless hacA (hacA-i). Furthermore, UPR was observed to be induced by amylolytic gene expression, and the disruption of the transcriptional activator for amylolytic genes resulted in partial growth restoration of the ireA-repressing strain. In addition, a homokaryotic ireA disruption mutant was successfully generated using the strain harboring hacA-i as a parental host. These results indicated that UPR is required for A. oryzae growth to alleviate ER stress induced by excessive production of hydrolytic enzymes. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Identification of Pectin Degrading Enzymes Secreted by Xanthomonas oryzae pv. oryzae and Determination of Their Role in Virulence on Rice.

    Science.gov (United States)

    Tayi, Lavanya; Maku, Roshan V; Patel, Hitendra Kumar; Sonti, Ramesh V

    2016-01-01

    Xanthomonas oryzae pv.oryzae (Xoo) causes the serious bacterial blight disease of rice. Xoo secretes a repertoire of plant cell wall degrading enzymes (CWDEs) like cellulases, xylanases, esterases etc., which act on various components of the rice cell wall. The major cellulases and xylanases secreted by Xoo have been identified and their role in virulence has been determined. In this study, we have identified some of the pectin degrading enzymes of Xoo and assessed their role in virulence. Bioinformatics analysis indicated the presence of four pectin homogalacturonan (HG) degrading genes in the genome of Xoo. The four HG degrading genes include one polygalacturonase (pglA), one pectin methyl esterase (pmt) and two pectate lyases (pel and pelL). There was no difference in the expression of pglA, pmt and pel genes by laboratory wild type Xoo strain (BXO43) grown in either nutrient rich PS medium or in plant mimic XOM2 medium whereas the expression of pelL gene was induced in XOM2 medium as indicated by qRT-PCR experiments. Gene disruption mutations were generated in each of these four genes. The polygalacturonase mutant pglA- was completely deficient in degrading the substrate Na-polygalacturonicacid (PGA). Strains carrying mutations in the pmt, pel and pelL genes were as efficient as wild type Xoo (BXO43) in cleaving PGA. These observations clearly indicate that PglA is the major pectin degrading enzyme produced by Xoo. The pectin methyl esterase, Pmt, is the pectin de-esterifying enzyme secreted by Xoo as evident from the enzymatic activity assay performed using pectin as the substrate. Mutations in the pglA, pmt, pel and pelL genes have minimal effects on virulence. This suggests that, as compared to cellulases and xylanases, the HG degrading enzymes may not have a major role in the pathogenicity of Xoo.

  13. Identification of Pectin Degrading Enzymes Secreted by Xanthomonas oryzae pv. oryzae and Determination of Their Role in Virulence on Rice.

    Directory of Open Access Journals (Sweden)

    Lavanya Tayi

    Full Text Available Xanthomonas oryzae pv.oryzae (Xoo causes the serious bacterial blight disease of rice. Xoo secretes a repertoire of plant cell wall degrading enzymes (CWDEs like cellulases, xylanases, esterases etc., which act on various components of the rice cell wall. The major cellulases and xylanases secreted by Xoo have been identified and their role in virulence has been determined. In this study, we have identified some of the pectin degrading enzymes of Xoo and assessed their role in virulence. Bioinformatics analysis indicated the presence of four pectin homogalacturonan (HG degrading genes in the genome of Xoo. The four HG degrading genes include one polygalacturonase (pglA, one pectin methyl esterase (pmt and two pectate lyases (pel and pelL. There was no difference in the expression of pglA, pmt and pel genes by laboratory wild type Xoo strain (BXO43 grown in either nutrient rich PS medium or in plant mimic XOM2 medium whereas the expression of pelL gene was induced in XOM2 medium as indicated by qRT-PCR experiments. Gene disruption mutations were generated in each of these four genes. The polygalacturonase mutant pglA- was completely deficient in degrading the substrate Na-polygalacturonicacid (PGA. Strains carrying mutations in the pmt, pel and pelL genes were as efficient as wild type Xoo (BXO43 in cleaving PGA. These observations clearly indicate that PglA is the major pectin degrading enzyme produced by Xoo. The pectin methyl esterase, Pmt, is the pectin de-esterifying enzyme secreted by Xoo as evident from the enzymatic activity assay performed using pectin as the substrate. Mutations in the pglA, pmt, pel and pelL genes have minimal effects on virulence. This suggests that, as compared to cellulases and xylanases, the HG degrading enzymes may not have a major role in the pathogenicity of Xoo.

  14. Analysis of an acyl-CoA binding protein in Aspergillus oryzae that undergoes unconventional secretion.

    Science.gov (United States)

    Kwon, Hee Su; Kawaguchi, Kouhei; Kikuma, Takashi; Takegawa, Kaoru; Kitamoto, Katsuhiko; Higuchi, Yujiro

    2017-11-04

    Acyl-CoA binding protein (ACBP) plays important roles in the metabolism of lipids in eukaryotic cells. In the industrially important filamentous fungus Aspergillus oryzae, although we have previously demonstrated that the A. oryzae ACBP (AoACBP) localizes to punctate structures and exhibits long-range motility, which is dependent on autophagy-related proteins, the physiological role of AoACBP remains elusive. Here, we describe identification and characterization of another ACBP from A. oryzae; we named this ACBP as AoAcb2 and accordingly renamed AoACBP as AoAcb1. The deduced amino acid sequence of AoAcb2 lacked a signal peptide. Phylogenetic analysis classified AoAcb2 into a clade that was same as the ACBP Acb1 of the model yeast Saccharomyces cerevisiae, but was different from that of AoAcb1. In contrast to punctate localization of AoAcb1, AoAcb2 was found to be dispersedly distributed in the cytoplasm, as was previously observed for the S. cerevisiae Acb1. Since we could not generate an Aoacb2 disruptant, we created an Aoacb2 conditional mutant that exhibited less growth under Aoacb2-repressed condition, suggesting that Aoacb2 is an essential gene for growth. Moreover, we observed that A. oryzae AoAcb2, but not A. oryzae AoAcb1, was secreted under carbon-starved condition, suggesting that AoAcb2 might be secreted via the unconventional protein secretion (UPS) pathway, just like S. cerevisiae Acb1. We also demonstrated that the unconventional secretion of AoAcb2 was dependent on the t-SNARE AoSso1, but was independent of the autophagy-related protein AoAtg1, suggesting that the unconventional secretion of AoAcb2, unlike that of S. cerevisiae Acb1, via the UPS pathway, is not regulated by the autophagy machinery. Thus, the filamentous fungus A. oryzae harbors two types of ACBPs, one of which appears to be essential for growth and undergoes unconventional secretion. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Ehd4 encodes a novel and Oryza-genus-specific regulator of photoperiodic flowering in rice.

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    He Gao

    Full Text Available Land plants have evolved increasingly complex regulatory modes of their flowering time (or heading date in crops. Rice (Oryza sativa L. is a short-day plant that flowers more rapidly in short-day but delays under long-day conditions. Previous studies have shown that the CO-FT module initially identified in long-day plants (Arabidopsis is evolutionary conserved in short-day plants (Hd1-Hd3a in rice. However, in rice, there is a unique Ehd1-dependent flowering pathway that is Hd1-independent. Here, we report isolation and characterization of a positive regulator of Ehd1, Early heading date 4 (Ehd4. ehd4 mutants showed a never flowering phenotype under natural long-day conditions. Map-based cloning revealed that Ehd4 encodes a novel CCCH-type zinc finger protein, which is localized to the nucleus and is able to bind to nucleic acids in vitro and transactivate transcription in yeast, suggesting that it likely functions as a transcriptional regulator. Ehd4 expression is most active in young leaves with a diurnal expression pattern similar to that of Ehd1 under both short-day and long-day conditions. We show that Ehd4 up-regulates the expression of the "florigen" genes Hd3a and RFT1 through Ehd1, but it acts independently of other known Ehd1 regulators. Strikingly, Ehd4 is highly conserved in the Oryza genus including wild and cultivated rice, but has no homologs in other species, suggesting that Ehd4 is originated along with the diversification of the Oryza genus from the grass family during evolution. We conclude that Ehd4 is a novel Oryza-genus-specific regulator of Ehd1, and it plays an essential role in photoperiodic control of flowering time in rice.

  16. Transposable elements as stress adaptive capacitors induce genomic instability in fungal pathogen Magnaporthe oryzae.

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    Sonia Chadha

    Full Text Available A fundamental problem in fungal pathogenesis is to elucidate the evolutionary forces responsible for genomic rearrangements leading to races with fitter genotypes. Understanding the adaptive evolutionary mechanisms requires identification of genomic components and environmental factors reshaping the genome of fungal pathogens to adapt. Herein, Magnaporthe oryzae, a model fungal plant pathogen is used to demonstrate the impact of environmental cues on transposable elements (TE based genome dynamics. For heat shock and copper stress exposed samples, eight TEs belonging to class I and II family were employed to obtain DNA profiles. Stress induced mutant bands showed a positive correlation with dose/duration of stress and provided evidences of TEs role in stress adaptiveness. Further, we demonstrate that genome dynamics differ for the type/family of TEs upon stress exposition and previous reports of stress induced MAGGY transposition has underestimated the role of TEs in M. oryzae. Here, we identified Pyret, MAGGY, Pot3, MINE, Mg-SINE, Grasshopper and MGLR3 as contributors of high genomic instability in M. oryzae in respective order. Sequencing of mutated bands led to the identification of LTR-retrotransposon sequences within regulatory regions of psuedogenes. DNA transposon Pot3 was identified in the coding regions of chromatin remodelling protein containing tyrosinase copper-binding and PWWP domains. LTR-retrotransposons Pyret and MAGGY are identified as key components responsible for the high genomic instability and perhaps these TEs are utilized by M. oryzae for its acclimatization to adverse environmental conditions. Our results demonstrate how common field stresses change genome dynamics of pathogen and provide perspective to explore the role of TEs in genome adaptability, signalling network and its impact on the virulence of fungal pathogens.

  17. Improved production of kojic acid by mutagenesis of Aspergillus flavus HAk1 and Aspergillus oryzae HAk2 and their potential antioxidant activity.

    Science.gov (United States)

    Ammar, Hala A M; Ezzat, Saeid M; Houseny, Asmaa M

    2017-10-01

    Two wild-type (WT) Aspergillus strains, A. flavus HAk1 and A. oryzae HAk2, were selected for kojic acid (KA) biosynthesis. Malt extract sucrose culture medium (MES) was the best culture medium for maximum production of KA. The maximum production of KA has been estimated at pH 4 after 7 days of incubation at 30 °C. Overproduction of KA was attained by mutagenesis of both A. flavus HAk1 and A. oryzae HAk2 through their exposer to different doses of gamma irradiation. The mutant strains (MT) A. flavus HAk1-M2 and A. oryzae HAk2-M26 were the most stable mutants for maximum production of KA through four generations. Yield of KA by A. oryzae HAk2-M26 and A. flavus HAk1-M2 has been 2.03-fold and 1.9-fold, respectively, higher than their wild-type strains. All WT and MT strains were used for KA production from different agricultural raw materials. Apple peel was the best waste for KA production by WT strains of A. flavus and A. oryzae, while orange peel and rice stalk are best material for KA production by MT strains, A. flavus HAk1-M2 and A. oryzae HAk2-M26, respectively. All experimental strains have the ability to produce considerable amounts of KA from sugarcane molasse (SCM) and sugar-beet molasse (SBM). SBM was better than SCM for KA production by all strains. The antioxidant activity of biosynthesizing KA was strongly affected with production conditions, where the highest antioxidant activity of all strains was recorded at the optimum environmental and nutritional conditions for KA production.

  18. The lipolytic activity of Rhizopus microsporus var rhizopodiformis isolat UICC No. 6

    Directory of Open Access Journals (Sweden)

    Doni Prayudi

    2002-12-01

    Full Text Available A study was carried out to examine the effect of peptone concentration (2,5% or 5%, inoculum concentration (0,1%, 0,5% or 1% and incubation period (0 – 96 hours, interval 12 hours on the lipolytic activity of Rhizopus microsporus var rhizopodiformis isolat UICC No. 6. Fermentation was done using the basal medium from Samad and the lipolytic activity on olive oil substrate was measured employing titration method with 0,05M NaOH. Lipolytic activity is expressed as unit/ml and one unit is defined as 1 Ωmol fatty acid liberated per minute. Results show that optimum lipolytic activity was obtained from 1 % inoculum, 5% peptone after 72 hours incubation period.

  19. Cloning and heterologous expression of the antibiotic peptide (ABP) genes from Rhizopus oligosporus NBRC 8631.

    Science.gov (United States)

    Yamada, Osamu; Sakamoto, Kazutoshi; Tominaga, Mihoko; Nakayama, Tasuku; Koseki, Takuya; Fujita, Akiko; Akita, Osamu

    2005-03-01

    We carried out protein sequencing of purified Antibiotic Peptide (ABP), and cloned two genes encoding this peptide as abp1 and abp2, from Rhizopus oligosporus NBRC 8631. Both genes contain an almost identical 231-bp segment, with only 3 nucleotide substitutions, encoding a 77 amino acid peptide. The abp gene product comprises a 28 amino acid signal sequence and a 49 amino acid mature peptide. Northern blot analysis showed that at least one of the abp genes is transcribed in R. oligosporus NBRC 8631. A truncated form of abp1 encoding only the mature peptide was fused with the alpha-factor signal peptide and engineered for expression in Pichia pastoris SMD1168H. Culture broth of the recombinant Pichia displayed ABP activity against Bacillus subtilis NBRC 3335 after induction of heterologous gene expression. This result indicates that mature ABP formed the active structure without the aid of other factors from R. oligosporus, and was secreted.

  20. KAJIAN PENGARUH KONSENTRASI Rhizopus sp. SEBAGAI AGEN PENGIKIS PROTEIN TERHADAP MUTU KULIT IKAN GURAMI TERSAMAK

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    Ratri Nur Hayati

    2013-06-01

    Full Text Available The study aimed to assess the effect of protease activity of Rhizopus sp. as a bating agent on the tanned carp leather quality, and their use for commercial leather products. The study was designed with a completely randomized design with four treatment, namely: the concentration of protease from Rhizopus sp. 0.5% (a1, 1.0% (a2, 1.5% (a3 and palkobat 1.0% (a4/control with 3 replications. Parameters were observed that is (1 protease activity of Rhizopus sp and palcobat; (2 Thickness (mm, tensile strength (N/cm2, tear strength (N/cm, elongation (%, enervation (mm, shrinkage temperature (ºC, fat/oil content (% of tanned leather; and (3 level of consumer acceptance (% and added valuead of comercial leather product. The data of tanned leather quality is then compared with SNI 06-4586-1998 concenring freshwater snake skin leather and chrome Burk’s Bay (1996 on the raw material quality leather products. The test results of protease activity of Rhizopus sp. = 7.97 mg/50mg/ jam and palkobat = 13.62 mg/50 mg/hour. The results of the analysis of tanned leather carp qulity sample from each treatment and comparison with the SNI as follows: (1 Thickness: 0.41 (a1, 0.38 (a2, 0.43 (a3, 0.41mm (a4 and ≥ 0.22 (SNI 06-4586-1998. Tensile strength: 1682.67; 1818.17; 1195.57; 1670.55 and 1,000N/cm2 (SNI. Tear strength: 314.87; 310.95; 332.06; 462.22, and 150.00 N/cm (SNI. Elongation: 93.33; 62.67; 56.67; 97.33, and <30.00% (SNI. Enervation: 1.87; 2.20; 1.63, 2.49, and ≥ 2.0 mm (Burk’s Bay, 1996. Shrinkage temperature: 74.00; 95.33; 96.33; 97.33, and ≥ 70.33ºC (SNI. The fat/oil content: 7.84; 8.17; 5.25; 8.49, and 2.00 to 6.00% (SNI. All treatments were tested has met the SNI quality, except elongation and fat/oil content. The level of consumer acceptance of the Oval HP Cover that is (1 aspects of the display (76.67% like and 23.33% dislike, (2 the use of convenience (66.67% like and 33.33% dislike , and (3 price (63.33% accepted and 23.67 reject. The

  1. Growth Simulation and Discrimination of Botrytis cinerea, Rhizopus stolonifer and Colletotrichum acutatum Using Hyperspectral Reflectance Imaging.

    Directory of Open Access Journals (Sweden)

    Ye Sun

    Full Text Available This research aimed to develop a rapid and nondestructive method to model the growth and discrimination of spoilage fungi, like Botrytis cinerea, Rhizopus stolonifer and Colletotrichum acutatum, based on hyperspectral imaging system (HIS. A hyperspectral imaging system was used to measure the spectral response of fungi inoculated on potato dextrose agar plates and stored at 28°C and 85% RH. The fungi were analyzed every 12 h over two days during growth, and optimal simulation models were built based on HIS parameters. The results showed that the coefficients of determination (R2 of simulation models for testing datasets were 0.7223 to 0.9914, and the sum square error (SSE and root mean square error (RMSE were in a range of 2.03-53.40×10(-4 and 0.011-0.756, respectively. The correlation coefficients between the HIS parameters and colony forming units of fungi were high from 0.887 to 0.957. In addition, fungi species was discriminated by partial least squares discrimination analysis (PLSDA, with the classification accuracy of 97.5% for the test dataset at 36 h. The application of this method in real food has been addressed through the analysis of Botrytis cinerea, Rhizopus stolonifer and Colletotrichum acutatum inoculated in peaches, demonstrating that the HIS technique was effective for simulation of fungal infection in real food. This paper supplied a new technique and useful information for further study into modeling the growth of fungi and detecting fruit spoilage caused by fungi based on HIS.

  2. Increased enzyme production under liquid culture conditions in the industrial fungus Aspergillus oryzae by disruption of the genes encoding cell wall α-1,3-glucan synthase.

    Science.gov (United States)

    Miyazawa, Ken; Yoshimi, Akira; Zhang, Silai; Sano, Motoaki; Nakayama, Mayumi; Gomi, Katsuya; Abe, Keietsu

    2016-09-01

    Under liquid culture conditions, the hyphae of filamentous fungi aggregate to form pellets, which reduces cell density and fermentation productivity. Previously, we found that loss of α-1,3-glucan in the cell wall of the fungus Aspergillus nidulans increased hyphal dispersion. Therefore, here we constructed a mutant of the industrial fungus A. oryzae in which the three genes encoding α-1,3-glucan synthase were disrupted (tripleΔ). Although the hyphae of the tripleΔ mutant were not fully dispersed, the mutant strain did form smaller pellets than the wild-type strain. We next examined enzyme productivity under liquid culture conditions by transforming the cutinase-encoding gene cutL1 into A. oryzae wild-type and the tripleΔ mutant (i.e. wild-type-cutL1, tripleΔ-cutL1). A. oryzae tripleΔ-cutL1 formed smaller hyphal pellets and showed both greater biomass and increased CutL1 productivity compared with wild-type-cutL1, which might be attributable to a decrease in the number of tripleΔ-cutL1 cells under anaerobic conditions.

  3. Lethal and mutagenic effects of ion beams and γ-rays in Aspergillus oryzae

    Energy Technology Data Exchange (ETDEWEB)

    Toyoshima, Yoshiyuki, E-mail: toyoshima@yamasa.com [Soy Sauce Laboratory, Yamasa Corporation, 2-10-1 Araoicho, Choshi, Chiba 288-0056 (Japan); Takahashi, Akemi; Tanaka, Hisaki; Watanabe, Jun; Mogi, Yoshinobu; Yamazaki, Tatsuo [Soy Sauce Laboratory, Yamasa Corporation, 2-10-1 Araoicho, Choshi, Chiba 288-0056 (Japan); Hamada, Ryoko; Iwashita, Kazuhiro [Fundamental Research Division, National Research Institute of Brewing, 3-7-1 Kagamiyama, Higashihiroshima, Hiroshima 739-0046 (Japan); Satoh, Katsuya; Narumi, Issay [Ion Beam Mutagenesis Research Group, Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

    2012-12-15

    Highlights: ► We investigated the effects of different LET radiation in A. oryzae. ► Both γ-rays and ion beams induced base substitutions, frameshifts, deletions. ► Both γ-rays and ion beams induced genome-wide large-scale mutations in A. oryzae. ► Some differences in the types and frequencies of mutations were found. ► Our results provide new basic insights into the mutation breeding of A. oryzae. - Abstract: Aspergillus oryzae is a fungus that is used widely in traditional Japanese fermentation industries. In this study, the lethal and mutagenic effects of different linear energy transfer (LET) radiation in freeze-dried conidia of A. oryzae were investigated. The lethal effect, which was evaluated by a 90% lethal dose, was dependent on the LET value of the ionizing radiation. The most lethal ionizing radiation among that tested was {sup 12}C{sup 5+} ion beams with an LET of 121 keV/μm. The {sup 12}C{sup 5+} ion beams had a 3.6-times higher lethal effect than low-LET (0.2 keV/μm) γ-rays. The mutagenic effect was evaluated by the frequency of selenate resistant mutants. {sup 12}C{sup 6+} ion beams with an LET of 86 keV/μm were the most effective in inducing selenate resistance. The mutant frequency following exposure to {sup 12}C{sup 6+} ion beams increased with an increase in dose and reached 3.47 × 10{sup −3} at 700 Gy. In the dose range from 0 to 700 Gy, {sup 12}C{sup 5+} ion beams were the second most effective in inducing selenate resistance, the mutant frequency of which reached a maximum peak (1.67 × 10{sup −3}) at 400 Gy. To elucidate the characteristics of mutation induced by ionizing radiation, mutations in the sulphate permease gene (sB) and ATP sulfurylase gene (sC) loci, the loss of function of which results in a selenate resistant phenotype, were compared between {sup 12}C{sup 5+} ion beams and γ-rays. We detected all types of transversions and transitions. For frameshifts, the frequency of a +1 frameshift was the highest in all

  4. Comparative effect of mutation of Aspergillus oryzae by gamma or ultraviolet irradiation

    International Nuclear Information System (INIS)

    Ito, Hitoshi; Nessa, A.

    1994-01-01

    Mutation frequency of Aspergillus oryzae IAM2630 was studied compared with gamma and ultraviolet irradiation. In this study, mutation frequency of morphological changes on survived colonies was increased up to 50% by irradiation of gamma-rays at survival fraction of 10 -3 to 10 -4 on potato-dextrose agar. On the contrary, mutation frequency of ultraviolet was obtained less than 17% at survival fraction of 10 -3 . Mutants with improvement of three-to-five hold production of α-amylase were isolated by irradiation of gamma-rays at 1.2 kGy. However, we could not isolate any mutants of higher production of α-amylase by ultraviolet irradiation. (author)

  5. Comparative effect of mutation of Aspergillus oryzae by gamma or ultraviolet irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hitoshi; Nessa, A. [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1994-08-01

    Mutation frequency of Aspergillus oryzae IAM2630 was studied compared with gamma and ultraviolet irradiation. In this study, mutation frequency of morphological changes on survived colonies was increased up to 50% by irradiation of gamma-rays at survival fraction of 10{sup -3} to 10{sup -4} on potato-dextrose agar. On the contrary, mutation frequency of ultraviolet was obtained less than 17% at survival fraction of 10{sup -3}. Mutants with improvement of three-to-five hold production of {alpha}-amylase were isolated by irradiation of gamma-rays at 1.2 kGy. However, we could not isolate any mutants of higher production of {alpha}-amylase by ultraviolet irradiation. (author).

  6. Glycogen Metabolic Genes Are Involved in Trehalose-6-Phosphate Synthase-Mediated Regulation of Pathogenicity by the Rice Blast Fungus Magnaporthe oryzae

    Science.gov (United States)

    Wilson, Richard A.; Wang, Zheng-Yi; Kershaw, Michael J.; Talbot, Nicholas J.

    2013-01-01

    The filamentous fungus Magnaporthe oryzae is the causal agent of rice blast disease. Here we show that glycogen metabolic genes play an important role in plant infection by M. oryzae. Targeted deletion of AGL1 and GPH1, which encode amyloglucosidase and glycogen phosphorylase, respectively, prevented mobilisation of glycogen stores during appressorium development and caused a significant reduction in the ability of M. oryzae to cause rice blast disease. By contrast, targeted mutation of GSN1, which encodes glycogen synthase, significantly reduced the synthesis of intracellular glycogen, but had no effect on fungal pathogenicity. We found that loss of AGL1 and GPH1 led to a reduction in expression of TPS1 and TPS3, which encode components of the trehalose-6-phosphate synthase complex, that acts as a genetic switch in M. oryzae. Tps1 responds to glucose-6-phosphate levels and the balance of NADP/NADPH to regulate virulence-associated gene expression, in association with Nmr transcriptional inhibitors. We show that deletion of the NMR3 transcriptional inhibitor gene partially restores virulence to a Δagl1Δgph1 mutant, suggesting that glycogen metabolic genes are necessary for operation of the NADPH-dependent genetic switch in M. oryzae. PMID:24098112

  7. eNose technology can detect and classify human pathogenic molds in vitro: a proof-of-concept study of Aspergillus fumigatus and Rhizopus oryzae

    NARCIS (Netherlands)

    de Heer, K.; Vonk, S. I.; Kok, M.; Kolader, M.; Zwinderman, A. H.; van Oers, M. H. J.; Sterk, P. J.; Visser, C. E.

    2016-01-01

    Invasive pulmonary mold disease (IPMD) is often fatal in neutropenic patients. This is because IPMD is difficult to diagnose timely, especially when non-Aspergillus molds are the causative agent, as they are usually not associated with a positive galactomannan assay. In 2013 we showed that exhaled

  8. Biodegradação de deoxinivalenol por aspergillus oryzae e rhizopus sp.: um estudo bioquímico de degradação e toxicidade

    OpenAIRE

    Buffon, Jaqueline Garda

    2008-01-01

    A contaminação aleatória de alimentos por micotoxinas afeta as condições de sanidade das dietas de humanos e animais. Dentre as toxinas fúngicas, deoxinivalenol (DON) se destaca pela freqüente contaminação de produtos agrícolas e alimentos e pela sua resistência a degradação pelo emprego de métodos tradicionais de processamento, o que motiva políticas de controle e a busca por técnicas de descontaminação. A descontaminação biológica empregando processsos fermentativos tem sido ...

  9. Induction of drought tolerant mutants of rice

    International Nuclear Information System (INIS)

    El-Hissewy, A.A.; Abd Allah, A.

    2001-01-01

    The ultimate goal of crop breeding is to develop varieties with a high yield potential and desirable agronomic characteristics. In Egypt, the most important qualities sought by breeders have been high yield potential, resistance to major diseases and insects, and improved grain and eating quality. However, breeding efforts should concentrate on varieties with the potential to minimize yield losses under unfavorable conditions such as drought, and to maximize yields when conditions are favorable. Rice (Oryza sativa L.) in Egypt is completely irrigated and a significant portion of the rice cultivated area is subject to water deficit resulting from an inadequate or insufficient irrigation supply. Drought tolerance is a complex trait in that it results from the interaction of histological and physiological characters of plant with environmental factors, both above-ground and under-ground. Accordingly, root characters are closely related to drought tolerance. Little attention has been paid in Egyptian breeding programs to root characters and their relation to shoot characters. Furthermore, induced mutations are considered as one of the most important methods to induce useful mutants, especially with improved root characters, to overcome the drought problem. The present investigation aimed to study the effect of different doses of gamma rays on several characters of three Egyptian rice varieties, i.e. 'Giza 171', 'Giza 175' and 'Giza 176' and to induce one or more mutants possessing drought tolerance

  10. Rice bacterial blight pathogen Xanthomonas oryzae pv. oryzae produces multiple DSF-family signals in regulation of virulence factor production

    Directory of Open Access Journals (Sweden)

    Cha Jae-Soon

    2010-07-01

    Full Text Available Abstract Background Xanthomonas oryzae pv. oryzae (Xoo is the causal agent of rice bacterial blight disease. Xoo produces a range of virulence factors, including EPS, extracellular enzyme, iron-chelating siderophores, and type III-secretion dependent effectors, which are collectively essential for virulence. Genetic and genomics evidence suggest that Xoo might use the diffusible signal factor (DSF type quorum sensing (QS system to regulate the virulence factor production. However, little is known about the chemical structure of the DSF-like signal(s produced by Xoo and the factors influencing the signal production. Results Xoo genome harbours an rpf cluster comprising rpfB, rpfF, rpfC and rpfG. The proteins encoded by these genes are highly homologous to their counterparts in X. campestris pv. campestris (Xcc, suggesting that Xcc and Xoo might use similar mechanisms for DSF biosynthesis and autoregulation. Consistent with in silico analysis, the rpfF mutant was DSF-deficient and the rpfC mutant produced about 25 times higher DSF-like activity than the wild type Xoo strain KACC10331. From the supernatants of rpfC mutant, we purified three compounds showing strong DSF-like activity. Mass spectrometry and NMR analysis revealed that two of them were the previously characterized DSF and BDSF; the third one was a novel unsaturated fatty acid with 2 double bonds and was designated as CDSF in this study. Further analysis showed that all the three DSF-family signals were synthesized via the enzyme RpfF encoded by Xoo2868. DSF and BDSF at a final concentration of 3 μM to the rpfF mutant could fully restore its extracellular xylanase activity and EPS production to the wild type level, but CDSF was less active than DSF and BDSF in induction of EPS and xylanase. DSF and CDSF shared a similar cell density-dependent production time course with the maximum production being detected at 42 h after inoculation, whereas the maximum production of BDSF was observed

  11. Comparative proteomics of Rhizopus delemar ATCC 20344 unravels the role of amino acid catabolism in fumarate accumulation

    OpenAIRE

    Odoni, Dorett I.; Tamayo-Ramos, Juan A.; Sloothaak, Jasper; van Heck, Ruben G.A.; Martins dos Santos, Vitor A.P.; de Graaff, Leo H.; Suarez-Diez, Maria; Schaap, Peter J.

    2017-01-01

    The filamentous fungus Rhizopus delemar naturally accumulates relatively high amounts of fumarate. Although the culture conditions that increase fumarate yields are well established, the network underlying the accumulation of fumarate is not yet fully understood. We set out to increase the knowledge about fumarate accumulation in R. delemar. To this end, we combined a transcriptomics and proteomics approach to identify key metabolic pathways involved in fumarate production in R. delemar, and ...

  12. Lethal and mutagenic effects of ion beams and γ-rays in Aspergillus oryzae.

    Science.gov (United States)

    Toyoshima, Yoshiyuki; Takahashi, Akemi; Tanaka, Hisaki; Watanabe, Jun; Mogi, Yoshinobu; Yamazaki, Tatsuo; Hamada, Ryoko; Iwashita, Kazuhiro; Satoh, Katsuya; Narumi, Issay

    2012-12-01

    Aspergillus oryzae is a fungus that is used widely in traditional Japanese fermentation industries. In this study, the lethal and mutagenic effects of different linear energy transfer (LET) radiation in freeze-dried conidia of A. oryzae were investigated. The lethal effect, which was evaluated by a 90% lethal dose, was dependent on the LET value of the ionizing radiation. The most lethal ionizing radiation among that tested was (12)C(5+) ion beams with an LET of 121keV/μm. The (12)C(5+) ion beams had a 3.6-times higher lethal effect than low-LET (0.2keV/μm) γ-rays. The mutagenic effect was evaluated by the frequency of selenate resistant mutants. (12)C(6+) ion beams with an LET of 86keV/μm were the most effective in inducing selenate resistance. The mutant frequency following exposure to (12)C(6+) ion beams increased with an increase in dose and reached 3.47×10(-3) at 700Gy. In the dose range from 0 to 700Gy, (12)C(5+) ion beams were the second most effective in inducing selenate resistance, the mutant frequency of which reached a maximum peak (1.67×10(-3)) at 400Gy. To elucidate the characteristics of mutation induced by ionizing radiation, mutations in the sulphate permease gene (sB) and ATP sulfurylase gene (sC) loci, the loss of function of which results in a selenate resistant phenotype, were compared between (12)C(5+) ion beams and γ-rays. We detected all types of transversions and transitions. For frameshifts, the frequency of a +1 frameshift was the highest in all cases. Although the incidence of deletions >2bp was generally low, deletions >20bp were characteristic for (12)C(5+) ion beams. γ-rays had a tendency to generate mutants carrying a multitude of mutations in the same locus. Both forms of radiation also induced genome-wide large-scale mutations including chromosome rearrangements and large deletions. These results provide new basic insights into the mutation breeding of A. oryzae using ionizing radiation. Crown Copyright © 2012. Published

  13. Promising rice mutants

    International Nuclear Information System (INIS)

    Hakim, L.; Azam, M.A.; Miah, A.J.; Mansur, M.A.; Akanda, H.R.

    1988-01-01

    Two induced mutants namely, Mut NS 1 (tall) and Mut NS 5 (semi-dwarf) derived from rice variety Nizersail were evaluated for various agronomic characters at four locations in Bangladesh. Both the mutants matured about three weeks earlier and yielded significantly higher than the parent variety Nizersail. (author). 3 tabs., 9 refs

  14. Rice Snl6, a cinnamoyl-CoA reductase-like gene family member, is required for NH1-mediated immunity to Xanthomonas oryzae pv. oryzae.

    Directory of Open Access Journals (Sweden)

    Rebecca S Bart

    2010-09-01

    Full Text Available Rice NH1 (NPR1 homolog 1 is a key mediator of innate immunity. In both plants and animals, the innate immune response is often accompanied by rapid cell death at the site of pathogen infection. Over-expression of NH1 in rice results in resistance to the bacterial pathogen, Xanthomonas oryzae pv. oryzae (Xoo, constitutive expression of defense related genes and enhanced benzothiadiazole (BTH- mediated cell death. Here we describe a forward genetic screen that identified a suppressor of NH1-mediated lesion formation and resistance, snl6. Comparative genome hybridization and fine mapping rapidly identified the genomic location of the Snl6 gene. Snl6 is a member of the cinnamoyl-CoA reductase (CCR-like gene family. We show that Snl6 is required for NH1-mediated resistance to Xoo. Further, we show that Snl6 is required for pathogenesis-related gene expression. In contrast to previously described CCR family members, disruption of Snl6 does not result in an obvious morphologic phenotype. Snl6 mutants have reduced lignin content and increased sugar extractability, an important trait for the production of cellulosic biofuels. These results suggest the existence of a conserved group of CCR-like genes involved in the defense response, and with the potential to alter lignin content without affecting development.

  15. Comparative proteome analysis of Aspergillus oryzae 3.042 and A. oryzae 100-8 strains: Towards the production of different soy sauce flavors.

    Science.gov (United States)

    Zhao, Guozhong; Hou, Lihua; Yao, Yunping; Wang, Chunling; Cao, Xiaohong

    2012-07-16

    Aspergillus oryzae plays a central role in soybean fermentation, particularly in its contribution to the flavor of soy sauce. We present a comparative assessment of the intracellular differences between wild-type strain 3.042 and mutant strain A100-8, at the proteome level. 522 different protein spots were identified by MALDI-TOF MS, with 134 spots being confirmed by MALDI-TOF MS/MS. Of these, 451 were differentially expressed proteins (DEPs). There was at least a two-fold increase for 288 spots, and at least a two-fold decrease for 163 spots, in strain A100-8 when compared to 3.042. Further analysis showed that 63 of the more abundant proteins were involved in glycolysis and the citrate cycle; 43 more abundant proteins and 10 less abundant proteins were related to amino acid biosynthesis and metabolism; two of the more abundant proteins were involved in vitamin biosynthesis; and five of the more abundant proteins and four of the less abundant proteins were related to secondary metabolites. Moreover, quantitative real time PCR showed that the mRNA expression levels of six typical genes we selected were consistent with changes in protein expression. We postulate that there may be a relationship between DEPs and the flavor formation mechanism in A. oryzae. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

  16. PRODUCTION AND CHARACTERIZATION OF CELLULOLYTIC ENZYMES BY ASPERGILLUS NIGER AND RHIZOPUS SP . BY SOLID STATE FERMENTATION OF PRICKLY PEAR

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    TAMIRES CARVALHO DOS SANTOS

    2016-01-01

    Full Text Available Prickly palm cactus husk was used as a solid - state fermentation support substrate for the production of cellulolytic enzymes using Aspergillus niger and Rhizopus sp. A Box - Behnken design was used to evaluate the effects of water activity, fermentation time and temperature on endoglucanase and total cellulase production. Response Surface Methodology showed that optimum conditions for endoglucanase production were achieved at after 70.35 h of fermentation at 29.56°C and a water activity of 0.875 for Aspergillus niger and after 68.12 h at 30.41°C for Rhizopus sp. Optimum conditions for total cellulase production were achieved after 74.27 h of fermentation at 31.22°C for Aspergillus niger and after 72.48 h and 27.86°C for Rhizopus sp . Water activity had a significant effect on Aspergillus niger endoglucanase production only. In industrial applications, enzymatic characterization is important for optimizing variables such as temperature and pH. In this study we showed that endoglucanase and total cellulase had a high level of thermostability and pH stability in all the enzymatic extracts. Enzymatic deactivation kinetic experiments indicated that the enzymes remained active after the freezing of the crude extract. Based on the results, bioconversion of cactus is an excellent alternative for the production of thermostable enzymes.

  17. Mutant heterosis in rice

    International Nuclear Information System (INIS)

    1987-01-01

    In the variety TKM6 a high yielding semidwarf mutant has been induced. This TKM6 mutant was used in test crosses with a number of other varieties and mutants to examine the extent of heterosis of dwarfs in rice and to select superior crosses. An excerpt of the published data is given. It appears from the backcross of the mutant with its original variety, that an increase in number of productive tillers occurs in the hybrid, leading to a striking grain yield increase, while the semi-dwarf culm length (the main mutant character) reverts to the normal phenotype. In the cross with IR8 on the other hand, there is only a minimal increase in tiller number but a substantial increase in TGW leading to more than 30% yield increase over the better parent

  18. GATA-Dependent Glutaminolysis Drives Appressorium Formation in Magnaporthe oryzae by Suppressing TOR Inhibition of cAMP/PKA Signaling.

    Science.gov (United States)

    Marroquin-Guzman, Margarita; Wilson, Richard A

    2015-04-01

    Fungal plant pathogens are persistent and global food security threats. To invade their hosts they often form highly specialized infection structures, known as appressoria. The cAMP/ PKA- and MAP kinase-signaling cascades have been functionally delineated as positive-acting pathways required for appressorium development. Negative-acting regulatory pathways that block appressorial development are not known. Here, we present the first detailed evidence that the conserved Target of Rapamycin (TOR) signaling pathway is a powerful inhibitor of appressorium formation by the rice blast fungus Magnaporthe oryzae. We determined TOR signaling was activated in an M. oryzae mutant strain lacking a functional copy of the GATA transcription factor-encoding gene ASD4. Δasd4 mutant strains could not form appressoria and expressed GLN1, a glutamine synthetase-encoding orthologue silenced in wild type. Inappropriate expression of GLN1 increased the intracellular steady-state levels of glutamine in Δasd4 mutant strains during axenic growth when compared to wild type. Deleting GLN1 lowered glutamine levels and promoted appressorium formation by Δasd4 strains. Furthermore, glutamine is an agonist of TOR. Treating Δasd4 mutant strains with the specific TOR kinase inhibitor rapamycin restored appressorium development. Rapamycin was also shown to induce appressorium formation by wild type and Δcpka mutant strains on non-inductive hydrophilic surfaces but had no effect on the MAP kinase mutant Δpmk1. When taken together, we implicate Asd4 in regulating intracellular glutamine levels in order to modulate TOR inhibition of appressorium formation downstream of cPKA. This study thus provides novel insight into the metabolic mechanisms that underpin the highly regulated process of appressorium development.

  19. GATA-Dependent Glutaminolysis Drives Appressorium Formation in Magnaporthe oryzae by Suppressing TOR Inhibition of cAMP/PKA Signaling.

    Directory of Open Access Journals (Sweden)

    Margarita Marroquin-Guzman

    2015-04-01

    Full Text Available Fungal plant pathogens are persistent and global food security threats. To invade their hosts they often form highly specialized infection structures, known as appressoria. The cAMP/ PKA- and MAP kinase-signaling cascades have been functionally delineated as positive-acting pathways required for appressorium development. Negative-acting regulatory pathways that block appressorial development are not known. Here, we present the first detailed evidence that the conserved Target of Rapamycin (TOR signaling pathway is a powerful inhibitor of appressorium formation by the rice blast fungus Magnaporthe oryzae. We determined TOR signaling was activated in an M. oryzae mutant strain lacking a functional copy of the GATA transcription factor-encoding gene ASD4. Δasd4 mutant strains could not form appressoria and expressed GLN1, a glutamine synthetase-encoding orthologue silenced in wild type. Inappropriate expression of GLN1 increased the intracellular steady-state levels of glutamine in Δasd4 mutant strains during axenic growth when compared to wild type. Deleting GLN1 lowered glutamine levels and promoted appressorium formation by Δasd4 strains. Furthermore, glutamine is an agonist of TOR. Treating Δasd4 mutant strains with the specific TOR kinase inhibitor rapamycin restored appressorium development. Rapamycin was also shown to induce appressorium formation by wild type and Δcpka mutant strains on non-inductive hydrophilic surfaces but had no effect on the MAP kinase mutant Δpmk1. When taken together, we implicate Asd4 in regulating intracellular glutamine levels in order to modulate TOR inhibition of appressorium formation downstream of cPKA. This study thus provides novel insight into the metabolic mechanisms that underpin the highly regulated process of appressorium development.

  20. Radiation induced mutants in elite genetic background for the augmentation of genetic diversity

    International Nuclear Information System (INIS)

    Kumar, V.; Bhagwat, S.G.

    2011-01-01

    Rice (Oryza sativa L.), an important food crop for India, shows large genetic diversity. However, despite the large genetic resource, high genetic similarity is reported in cultivated varieties indicating genetic erosion. Radiation induced mutations provide genetic variability in elite background. In the present study, twenty gamma ray induced mutants of rice variety WL112 (carrying sd-1 semi-dwarfing gene) were analysed for genetic diversity using microsatellite markers. The high range of genetic diversity among mutants indicated that the mutants possess potential for enhancing variability in rice. Cluster analysis showed presence of five clusters having small sub-clusters. Earliness, semi-dwarf stature or resistance to blast disease observed among the mutants showed that these will be useful in breeding programmes. (author)

  1. Elimination of Sitophilus oryzae (L.) by irradiation

    International Nuclear Information System (INIS)

    Castro, Fernanda Peixoto

    2005-01-01

    Food treatment by exposure to ionizing radiation, known as food irradiation, presents several attractive features such as: leaving no residues, posing no threat to consumer health, usually causing no damage to sensory or nutritional properties and acting uniformly throughout the volume of the products. This work investigated the efficiency of irradiation for eliminating Sitophilus oryzae (L.), also known as 'the rice weevil', a small beetle frequently found in infested grains. A total of 444 individuals of Sitophilus oryzae (L.) found in corn meal and noodles supplies were irradiated with gamma ray doses of 0, 0.6, 0.9, 1.0, 1.2, 1.5 and 2.0 kGy and then visually monitored for 4 days in order to determine the number of insects still alive. The least-squares fitting method was used to determine the survival curves as functions of post-irradiation time and dose. The living fraction of the irradiated population was found to decrease exponentially with time. The results indicated that doses of 2.0, 1.5 and 0.6 kGy cause immediate death, instantaneous immobility and death of the species within one week, respectively. The findings suggest that disinfestation of Sitophilus oryzae (L.) by irradiation is an interesting option to the dangerous use of toxic chemicals. (author)

  2. Elimination of Sitophilus oryzae (L.) by irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Fernanda Peixoto [Exercito Brasileiro, Brasilia, DF (Brazil). Diretoria de Suprimento. Dept. Logistico]. E-mail: peixotocastro@dlog.eb.mil.br; Vital, Helio de Carvalho [Centro Tecnologico do Exercito (CTEx), Rio de Janeiro, RJ (brazil)]. E-mail: vital@ctex.eb.br

    2005-07-01

    Food treatment by exposure to ionizing radiation, known as food irradiation, presents several attractive features such as: leaving no residues, posing no threat to consumer health, usually causing no damage to sensory or nutritional properties and acting uniformly throughout the volume of the products. This work investigated the efficiency of irradiation for eliminating Sitophilus oryzae (L.), also known as 'the rice weevil', a small beetle frequently found in infested grains. A total of 444 individuals of Sitophilus oryzae (L.) found in corn meal and noodles supplies were irradiated with gamma ray doses of 0, 0.6, 0.9, 1.0, 1.2, 1.5 and 2.0 kGy and then visually monitored for 4 days in order to determine the number of insects still alive. The least-squares fitting method was used to determine the survival curves as functions of post-irradiation time and dose. The living fraction of the irradiated population was found to decrease exponentially with time. The results indicated that doses of 2.0, 1.5 and 0.6 kGy cause immediate death, instantaneous immobility and death of the species within one week, respectively. The findings suggest that disinfestation of Sitophilus oryzae (L.) by irradiation is an interesting option to the dangerous use of toxic chemicals. (author)

  3. Bioconversion of Capsaicin by Aspergillus oryzae.

    Science.gov (United States)

    Lee, Minji; Cho, Jeong-Yong; Lee, Yu Geon; Lee, Hyoung Jae; Lim, Seong-Il; Park, So-Lim; Moon, Jae-Hak

    2015-07-08

    This study identified metabolites of capsaicin bioconverted by Aspergillus oryzae, which is generally used for mass production of gochujang prepared by fermenting red pepper powder in Korea. A. oryzae was incubated with capsaicin in potato dextrose broth. Capsaicin decreased depending on the incubation period, but new metabolites increased. Five capsaicin metabolites purified from the ethyl acetate fraction of the capsaicin culture were identified as N-vanillylcarbamoylbutyric acid, N-vanillyl-9-hydroxy-8-methyloctanamide, ω-hydroxycapsaicin, 8-methyl-N-vanillylcarbamoyl-6(E)-octenoic acid, and 2-methyl-N-vanillylcarbamoyl-6(Z)-octenoic acid by nuclear magnetic resonance (NMR) and mass spectrometry (MS). The capsaicin metabolites in gochujang were confirmed and quantitated by selective multiple reaction monitoring detection after liquid chromatography electrospray ionization MS using the isolated compounds as external standards. On the basis of the structures of the capsaicin metabolites, it is proposed that capsaicin metabolites were converted by A. oryzae by ω-hydroxylation, alcohol oxidation, hydrogenation, isomerization, and α- and/or β-oxidation.

  4. Mutagenesis of Aspergillus oryzae IPT-301 to improve the production of β-fructofuranosidase

    Directory of Open Access Journals (Sweden)

    Beatriz Guilarte Maresma

    2010-03-01

    Full Text Available Aspergillus oryzae IPT-301, previously reported as a β-fructofuranosidase producing microorganism, was successfully mutated using UV irradiation at 253.7 nm followed by the screening of survivors resistant to certain stress conditions. Strains were first subjected to the β-fructofuranosidase activity assay using a portion from the colony grown in Petri dish as the enzyme source. Seven mutants with fructofuranosidase activity values relative to the parent culture between 140 -190% were selected from survivors grown at temperature of 40ºC or 0.018% (w/v sodium dodecyl sulfate concentration. They were cultivated on a rotary shaker to characterize mycelium and extracellular fructosyltransferase activities. Three mutants named IPT-745, IPT-746 and IPT-748 showed the highest amount of mycelium activity whose values increased 1.5 -1.8 fold, compared with the parent strain. It was found that more than 55% of total enzyme activity (mycelium- plus extracellular- activity from these strains was detected in the mycelium fraction. Only one mutant, IPT-747, exceeded the amount of extracellular enzyme exhibited by the parent strain (1.5 times. This mutant also showed the highest value of total fructosyltransferase activity.

  5. Elusive Origins of the Extra Genes in Aspergillus oryzae

    Science.gov (United States)

    Khaldi, Nora; Wolfe, Kenneth H.

    2008-01-01

    The genome sequence of Aspergillus oryzae revealed unexpectedly that this species has approximately 20% more genes than its congeneric species A. nidulans and A. fumigatus. Where did these extra genes come from? Here, we evaluate several possible causes of the elevated gene number. Many gene families are expanded in A. oryzae relative to A. nidulans and A. fumigatus, but we find no evidence of ancient whole-genome duplication or other segmental duplications, either in A. oryzae or in the common ancestor of the genus Aspergillus. We show that the presence of divergent pairs of paralogs is a feature peculiar to A. oryzae and is not shared with A. nidulans or A. fumigatus. In phylogenetic trees that include paralog pairs from A. oryzae, we frequently find that one of the genes in a pair from A. oryzae has the expected orthologous relationship with A. nidulans, A. fumigatus and other species in the subphylum Eurotiomycetes, whereas the other A. oryzae gene falls outside this clade but still within the Ascomycota. We identified 456 such gene pairs in A. oryzae. Further phylogenetic analysis did not however indicate a single consistent evolutionary origin for the divergent members of these pairs. Approximately one-third of them showed phylogenies that are suggestive of horizontal gene transfer (HGT) from Sordariomycete species, and these genes are closer together in the A. oryzae genome than expected by chance, but no unique Sordariomycete donor species was identifiable. The postulated HGTs from Sordariomycetes still leave the majority of extra A. oryzae genes unaccounted for. One possible explanation for our observations is that A. oryzae might have been the recipient of many separate HGT events from diverse donors. PMID:18725939

  6. Elusive origins of the extra genes in Aspergillus oryzae.

    Directory of Open Access Journals (Sweden)

    Nora Khaldi

    Full Text Available The genome sequence of Aspergillus oryzae revealed unexpectedly that this species has approximately 20% more genes than its congeneric species A. nidulans and A. fumigatus. Where did these extra genes come from? Here, we evaluate several possible causes of the elevated gene number. Many gene families are expanded in A. oryzae relative to A. nidulans and A. fumigatus, but we find no evidence of ancient whole-genome duplication or other segmental duplications, either in A. oryzae or in the common ancestor of the genus Aspergillus. We show that the presence of divergent pairs of paralogs is a feature peculiar to A. oryzae and is not shared with A. nidulans or A. fumigatus. In phylogenetic trees that include paralog pairs from A. oryzae, we frequently find that one of the genes in a pair from A. oryzae has the expected orthologous relationship with A. nidulans, A. fumigatus and other species in the subphylum Eurotiomycetes, whereas the other A. oryzae gene falls outside this clade but still within the Ascomycota. We identified 456 such gene pairs in A. oryzae. Further phylogenetic analysis did not however indicate a single consistent evolutionary origin for the divergent members of these pairs. Approximately one-third of them showed phylogenies that are suggestive of horizontal gene transfer (HGT from Sordariomycete species, and these genes are closer together in the A. oryzae genome than expected by chance, but no unique Sordariomycete donor species was identifiable. The postulated HGTs from Sordariomycetes still leave the majority of extra A. oryzae genes unaccounted for. One possible explanation for our observations is that A. oryzae might have been the recipient of many separate HGT events from diverse donors.

  7. Comparative genomic analysis identified a mutation related to enhanced heterologous protein production in the filamentous fungus Aspergillus oryzae.

    Science.gov (United States)

    Jin, Feng-Jie; Katayama, Takuya; Maruyama, Jun-Ichi; Kitamoto, Katsuhiko

    2016-11-01

    Genomic mapping of mutations using next-generation sequencing technologies has facilitated the identification of genes contributing to fundamental biological processes, including human diseases. However, few studies have used this approach to identify mutations contributing to heterologous protein production in industrial strains of filamentous fungi, such as Aspergillus oryzae. In a screening of A. oryzae strains that hyper-produce human lysozyme (HLY), we previously isolated an AUT1 mutant that showed higher production of various heterologous proteins; however, the underlying factors contributing to the increased heterologous protein production remained unclear. Here, using a comparative genomic approach performed with whole-genome sequences, we attempted to identify the genes responsible for the high-level production of heterologous proteins in the AUT1 mutant. The comparative sequence analysis led to the detection of a gene (AO090120000003), designated autA, which was predicted to encode an unknown cytoplasmic protein containing an alpha/beta-hydrolase fold domain. Mutation or deletion of autA was associated with higher production levels of HLY. Specifically, the HLY yields of the autA mutant and deletion strains were twofold higher than that of the control strain during the early stages of cultivation. Taken together, these results indicate that combining classical mutagenesis approaches with comparative genomic analysis facilitates the identification of novel genes involved in heterologous protein production in filamentous fungi.

  8. Purification and Characterisation of a Fibrinolytic Enzyme from Rhizopus micro sporus var. tuberosus

    Directory of Open Access Journals (Sweden)

    Shuli Zhang

    2015-01-01

    Full Text Available Extracellular fibrinolytic enzyme from Rhizopus microsporus var. tuberosus was purified and characterised. The microorganism was isolated in a distillery from daqu, a fermentative agent used in the production of Chinese liquor and vinegar at diff erent temperatures. The fibrinolytic enzyme was partially purifi ed by ammonium sulphate precipitation, dialysis, DEAE Sepharose® Fast Flow ion exchange chromatography and Sephadex G-75 gel filtration chromatography. The molecular mass of the fi brinolytic enzyme was estimated to be 24.5 kDa by SDS-PAGE. The purified enzyme showed optimal activity at pH=7.0 and 37 °C by fibrin plate method. It showed stronger resistance to the inhibition by trypsin and was stable at 37 °C retaining 96.1 % residual activity aft er 4 h of incubation. The fibrinolytic activity of the enzyme was enhanced by Na+, Ca2+, Mg2+ and Mn2+. Conversely, Zn2+ and Cu2+ partly inhibited enzymatic activity. Using fibrin plate method, we found that the enzyme not only degrades fibrin directly, but also activates plasminogen into plasmin to degrade fibrin. The results indicate that the pure enzyme has a potential in dissolving blood clot, and the possibility for application in the treatment of thrombosis.

  9. Protein enrichment of brewery spent grain from Rhizopus oligosporus by solid-state fermentation.

    Science.gov (United States)

    Canedo, Marianny Silva; de Paula, Fernanda Gomes; da Silva, Flávio Alves; Vendruscolo, Francielo

    2016-07-01

    Brewery spent grain represents approximately 85 % of total by-products generated in a brewery. Consisting of carbohydrates, fiber, minerals and low amounts of protein, the use of brewery spent grain is limited to the feeding of ruminants; however, its potential use should be investigated. The reuse of this by-product using microorganisms by solid-state fermentation process as the case of protein enrichment by single-cell protein incorporation is an alternative to ensure sustainability and generate commercially interesting products. In this context, the aim of this study was to grow Rhizopus oligosporus in brewery spent grain under different initial moisture contents and nitrogen sources to increase the protein content of the fermented material. After 7 days of fermentation, increase of 2-4 times in the crude protein and soluble protein content was verified, respectively, compared to unfermented brewery spent grain. The kinetics of protein enrichment demonstrated the possibility of application of this technique, which can be a great alternative for use in diets for animals.

  10. Evidence for a transketolase-mediated metabolic checkpoint governing biotrophic growth in rice cells by the blast fungus Magnaporthe oryzae.

    Directory of Open Access Journals (Sweden)

    Jessie Fernandez

    2014-09-01

    Full Text Available The blast fungus Magnaporthe oryzae threatens global food security through the widespread destruction of cultivated rice. Foliar infection requires a specialized cell called an appressorium that generates turgor to force a thin penetration hypha through the rice cuticle and into the underlying epidermal cells, where the fungus grows for the first days of infection as a symptomless biotroph. Understanding what controls biotrophic growth could open new avenues for developing sustainable blast intervention programs. Here, using molecular genetics and live-cell imaging, we dismantled M. oryzae glucose-metabolizing pathways to reveal that the transketolase enzyme, encoded by TKL1, plays an essential role in facilitating host colonization during rice blast disease. In the absence of transketolase, Δtkl1 mutant strains formed functional appressoria that penetrated rice cuticles successfully and developed invasive hyphae (IH in rice cells from primary hyphae. However, Δtkl1 could not undertake sustained biotrophic growth or cell-to-cell movement. Transcript data and observations using fluorescently labeled histone H1:RFP fusion proteins indicated Δtkl1 mutant strains were alive in host cells but were delayed in mitosis. Mitotic delay could be reversed and IH growth restored by the addition of exogenous ATP, a metabolite depleted in Δtkl1 mutant strains. We show that ATP might act via the TOR signaling pathway, and TOR is likely a downstream target of activation for TKL1. TKL1 is also involved in controlling the migration of appressorial nuclei into primary hyphae in host cells. When taken together, our results indicate transketolase has a novel role in mediating--via ATP and TOR signaling--an in planta-specific metabolic checkpoint that controls nuclear migration from appressoria into primary hyphae, prevents mitotic delay in early IH and promotes biotrophic growth. This work thus provides new information about the metabolic strategies employed by M

  11. Identification of a basic helix-loop-helix-type transcription regulator gene in Aspergillus oryzae by systematically deleting large chromosomal segments.

    Science.gov (United States)

    Jin, Feng Jie; Takahashi, Tadashi; Machida, Masayuki; Koyama, Yasuji

    2009-09-01

    We previously developed two methods (loop-out and replacement-type recombination) for generating large-scale chromosomal deletions that can be applied to more effective chromosomal engineering in Aspergillus oryzae. In this study, the replacement-type method is used to systematically delete large chromosomal DNA segments to identify essential and nonessential regions in chromosome 7 (2.93 Mb), which is the smallest A. oryzae chromosome and contains a large number of nonsyntenic blocks. We constructed 12 mutants harboring deletions that spanned 16- to 150-kb segments of chromosome 7 and scored phenotypic changes in the resulting mutants. Among the deletion mutants, strains designated Delta5 and Delta7 displayed clear phenotypic changes involving growth and conidiation. In particular, the Delta5 mutant exhibited vigorous growth and conidiation, potentially beneficial characteristics for certain industrial applications. Further deletion analysis allowed identification of the AO090011000215 gene as the gene responsible for the Delta5 mutant phenotype. The AO090011000215 gene was predicted to encode a helix-loop-helix binding protein belonging to the bHLH family of transcription factors. These results illustrate the potential of the approach for identifying novel functional genes.

  12. The Role of Aquaporins in pH-Dependent Germination of Rhizopus delemar Spores.

    Directory of Open Access Journals (Sweden)

    Tidhar Turgeman

    Full Text Available Rhizopus delemar and associated species attack a wide range of fruit and vegetables after harvest. Host nutrients and acidic pH are required for optimal germination of R. delemar, and we studied how this process is triggered. Glucose induced spore swelling in an acidic environment, expressed by an up to 3-fold increase in spore diameter, whereas spore diameter was smaller in a neutral environment. When suspended in an acidic environment, the spores started to float, indicating a change in their density. Treatment of the spores with HgCl2, an aquaporin blocker, prevented floating and inhibited spore swelling and germ-tube emergence, indicating the importance of water uptake at the early stages of germination. Two putative candidate aquaporin-encoding genes-RdAQP1 and RdAQP2-were identified in the R. delemar genome. Both presented the conserved NPA motif and six-transmembrane domain topology. Expressing RdAQP1 and RdAQP2 in Arabidopsis protoplasts increased the cells' osmotic water permeability coefficient (Pf compared to controls, indicating their role as water channels. A decrease in R. delemar aquaporin activity with increasing external pH suggested pH regulation of these proteins. Substitution of two histidine (His residues, positioned on two loops facing the outer side of the cell, with alanine eliminated the pH sensing resulting in similar Pf values under acidic and basic conditions. Since hydration is critical for spore switching from the resting to activate state, we suggest that pH regulation of the aquaporins can regulate the initial phase of R. delemar spore germination, followed by germ-tube elongation and host-tissue infection.

  13. A reductive aminase from Aspergillus oryzae

    OpenAIRE

    Grogan, Gideon James; Aleku, Godwin; France, Scott; Man, Henry Wing-Hong; Mangas-Sanchez, Juan; Sharma, Mahima; Montgomery, Sarah L; Leipold, Friedemann; Hussain, Shahed; Turner, Nicholas

    2017-01-01

    Reductive amination is one of the most important methods for the synthesis of chiral amines. Here we report the discovery of an NADP(H)-dependent reductive aminase from Aspergillus oryzae (AspRedAm, Uniprot code Q2TW47) which can catalyse the reductive coupling of a broad set of carbonyl compounds with a variety of primary and secondary amines with up to >98% conversion and with up to >98% enantiomeric excess. In cases where both carbonyl and amine show high reactivity, it is possible to empl...

  14. Harbouring public good mutants within a pathogen population can increase both fitness and virulence.

    Science.gov (United States)

    Lindsay, Richard J; Kershaw, Michael J; Pawlowska, Bogna J; Talbot, Nicholas J; Gudelj, Ivana

    2016-12-28

    Existing theory, empirical, clinical and field research all predict that reducing the virulence of individuals within a pathogen population will reduce the overall virulence, rendering disease less severe. Here, we show that this seemingly successful disease management strategy can fail with devastating consequences for infected hosts. We deploy cooperation theory and a novel synthetic system involving the rice blast fungus Magnaporthe oryzae . In vivo infections of rice demonstrate that M. oryzae virulence is enhanced, quite paradoxically, when a public good mutant is present in a population of high-virulence pathogens. We reason that during infection, the fungus engages in multiple cooperative acts to exploit host resources. We establish a multi-trait cooperation model which suggests that the observed failure of the virulence reduction strategy is caused by the interference between different social traits. Multi-trait cooperative interactions are widespread, so we caution against the indiscriminant application of anti-virulence therapy as a disease-management strategy.

  15. Comparative proteomics of Rhizopus delemar ATCC 20344 unravels the role of amino acid catabolism in fumarate accumulation

    Directory of Open Access Journals (Sweden)

    Dorett I. Odoni

    2017-03-01

    Full Text Available The filamentous fungus Rhizopus delemar naturally accumulates relatively high amounts of fumarate. Although the culture conditions that increase fumarate yields are well established, the network underlying the accumulation of fumarate is not yet fully understood. We set out to increase the knowledge about fumarate accumulation in R. delemar. To this end, we combined a transcriptomics and proteomics approach to identify key metabolic pathways involved in fumarate production in R. delemar, and propose that a substantial part of the fumarate accumulated in R. delemar during nitrogen starvation results from the urea cycle due to amino acid catabolism.

  16. The effect of different phosphate ion concentrations and ph of the phosphate buffer on lipase bioproduction by rhizopus oligosporus

    International Nuclear Information System (INIS)

    Haq, I.; Ali, S.; Awan, U.F.; Javed, W.; Mirza, S.

    2005-01-01

    In the present investigation, we report the effect of phosphate ion concentration and different ph of the phosphate buffer (as diluent) on lipase bioproduction by Rhizopus oligosporus. For this purpose, solid state fermentation was employed. Different agricultural by-products such as wheat bran, rice husk, almond meal, soybean meal and sunflower meal were used as substrate. The maximum lipase activity (72.60 U/g) was observed with the almond meal. Addition of phosphate ions (K/sub 2/HPO/sub 4/) influenced the lipase production. The ph of the phosphate buffer (7.0) was found to be effective for higher yield of lipase. (author)

  17. Highly efficient gene targeting in Aspergillus oryzae industrial strains under ligD mutation introduced by genome editing: Strain-specific differences in the effects of deleting EcdR, the negative regulator of sclerotia formation.

    Science.gov (United States)

    Nakamura, Hidetoshi; Katayama, Takuya; Okabe, Tomoya; Iwashita, Kazuhiro; Fujii, Wataru; Kitamoto, Katsuhiko; Maruyama, Jun-Ichi

    2017-07-11

    Numerous strains of Aspergillus oryzae are industrially used for Japanese traditional fermentation and for the production of enzymes and heterologous proteins. In A. oryzae, deletion of the ku70 or ligD genes involved in non-homologous end joining (NHEJ) has allowed high gene targeting efficiency. However, this strategy has been mainly applied under the genetic background of the A. oryzae wild strain RIB40, and it would be laborious to delete the NHEJ genes in many A. oryzae industrial strains, probably due to their low gene targeting efficiency. In the present study, we generated ligD mutants from the A. oryzae industrial strains by employing the CRISPR/Cas9 system, which we previously developed as a genome editing method. Uridine/uracil auxotrophic strains were generated by deletion of the pyrG gene, which was subsequently used as a selective marker. We examined the gene targeting efficiency with the ecdR gene, of which deletion was reported to induce sclerotia formation under the genetic background of the strain RIB40. As expected, the deletion efficiencies were high, around 60~80%, in the ligD mutants of industrial strains. Intriguingly, the effects of the ecdR deletion on sclerotia formation varied depending on the strains, and we found sclerotia-like structures under the background of the industrial strains, which have never been reported to form sclerotia. The present study demonstrates that introducing ligD mutation by genome editing is an effective method allowing high gene targeting efficiency in A. oryzae industrial strains.

  18. 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

  19. Effect of solid-state fermentation with Rhizopus oligosporus on bioactive compounds and antioxidant capacity of raw and roasted buckwheat groats

    Directory of Open Access Journals (Sweden)

    Wronkowska Małgorzata

    2015-12-01

    Full Text Available The effect of solid-state fermentation with Rhizopus oligosporus on the changes in the total phenolic compounds, rutin, vitamin B and C, tocopherol, phytic acid and antioxidant capacity of raw and roasted buckwheat groats was studied. The roasted groats contained reduced level of studied bioactive compounds as compared to raw groats. In this study was evidenced that the solidstate fermentation with Rhizopus oligosporus enhanced water soluble vitamins (thiamine, pyridoxine and L-ascorbic acid as well as tocopherols contents. In contrast the decrease of the inositol hexaphosphate, phenolic compounds, the rutin content and antioxidant capacity determined by ACL and ABTS methods was noticed.

  20. Variations in characters of diploid-like plants derived from gamma-irradiated tetraploids in rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    Yamamoto, K.; Fukuoka, H.; Kageyama, Y.; Takeda, G.

    1990-01-01

    Full text: Populations of artificial autotetraploids of rice (Oryza sativa L. cvs. 'Nipponbare' and 'Fukunishiki') were repeatedly irradiated with gamma-rays through several generations. Plants which did not differ in appearance from the original diploid plants occurred occasionally in the populations. Nine diploid-like plants were obtained so far, and their generations were advanced without irradiation in order to examine the mode of segregation of characters in their progeny. The results indicate that diploid-like plants with multiple mutant characters could be obtained and that dominant characters, i.e. awned spikelet and coloured apiculus, were included in the mutant characters. The diploid-like plants had 2n=24 chromosomes. (author)

  1. Two novel transcriptional regulators are essential for infection-related morphogenesis and pathogenicity of the rice blast fungus Magnaporthe oryzae.

    Directory of Open Access Journals (Sweden)

    Xia Yan

    2011-12-01

    Full Text Available The cyclic AMP-dependent protein kinase A signaling pathway plays a major role in regulating plant infection by the rice blast fungus Magnaporthe oryzae. Here, we report the identification of two novel genes, MoSOM1 and MoCDTF1, which were discovered in an insertional mutagenesis screen for non-pathogenic mutants of M. oryzae. MoSOM1 or MoCDTF1 are both necessary for development of spores and appressoria by M. oryzae and play roles in cell wall differentiation, regulating melanin pigmentation and cell surface hydrophobicity during spore formation. MoSom1 strongly interacts with MoStu1 (Mstu1, an APSES transcription factor protein, and with MoCdtf1, while also interacting more weakly with the catalytic subunit of protein kinase A (CpkA in yeast two hybrid assays. Furthermore, the expression levels of MoSOM1 and MoCDTF1 were significantly reduced in both Δmac1 and ΔcpkA mutants, consistent with regulation by the cAMP/PKA signaling pathway. MoSom1-GFP and MoCdtf1-GFP fusion proteins localized to the nucleus of fungal cells. Site-directed mutagenesis confirmed that nuclear localization signal sequences in MoSom1 and MoCdtf1 are essential for their sub-cellular localization and biological functions. Transcriptional profiling revealed major changes in gene expression associated with loss of MoSOM1 during infection-related development. We conclude that MoSom1 and MoCdtf1 functions downstream of the cAMP/PKA signaling pathway and are novel transcriptional regulators associated with cellular differentiation during plant infection by the rice blast fungus.

  2. Optimization of liquid-state fermentation conditions for the glyphosate degradation enzyme production of strain Aspergillus oryzae by ultraviolet mutagenesis.

    Science.gov (United States)

    Fu, Gui-Ming; Li, Ru-Yi; Li, Kai-Min; Hu, Ming; Yuan, Xiao-Qiang; Li, Bin; Wang, Feng-Xue; Liu, Cheng-Mei; Wan, Yin

    2016-11-16

    This study aimed to obtain strains with high glyphosate-degrading ability and improve the ability of glyphosate degradation enzyme by the optimization of fermentation conditions. Spore from Aspergillus oryzae A-F02 was subjected to ultraviolet mutagenesis. Single-factor experiment and response surface methodology were used to optimize glyphosate degradation enzyme production from mutant strain by liquid-state fermentation. Four mutant strains were obtained and named as FUJX 001, FUJX 002, FUJX 003, and FUJX 004, in which FUJX 001 gave the highest total enzyme activity. Starch concentration at 0.56%, GP concentration at 1,370 mg/l, initial pH at 6.8, and temperature at 30°C were the optimum conditions for the improved glyphosate degradation endoenzyme production of A. oryzae FUJX 001. Under these conditions, the experimental endoenzyme activity was 784.15 U/100 ml fermentation liquor. The result (784.15 U/100 ml fermentation liquor) was approximately 14-fold higher than that of the original strain. The result highlights the potential of glyphosate degradation enzyme to degrade glyphosate.

  3. Production of Cellulases by Rhizopus stolonifer from Glucose-Containing Media Based on the Regulation of Transcriptional Regulator CRE.

    Science.gov (United States)

    Zhang, Yingyiing; Tang, Bin; Du, Guocheng

    2017-03-28

    Carbon catabolite repression is a crucial regulation mechanism in microorganisms, but its characteristic in Rhizopus is still unclear. We extracted a carbon regulation gene, cre , that encoded a carbon catabolite repressor protein (CRE) from Rhizopus stolonifer TP-02, and studied the regulation of CRE by real-time qPCR. CRE responded to glucose in a certain range, where it could significantly regulate part of the cellulase genes ( eg, bg, and cbh2 ) without cbh1 . In the comparison of the response of cre and four cellulase genes to carboxymethylcellulose sodium and a simple carbon source (lactose), the effect of CRE was only related to the concentration of reducing sugars. By regulating the reducing sugars to range from 0.4% to 0.6%, a glucose-containing medium with lactose as the inducer could effectively induce cellulases without the repression of CRE. This regulation method could potentially reduce the cost of enzymes produced in industries and provide a possible solution to achieve the large-scale synthesis of cellulases.

  4. Self-affine fractal growth front of Aspergillus oryzae

    Science.gov (United States)

    Matsuura, Shu; Miyazima, Sasuke

    1992-12-01

    Aspergillus oryzae have been grown in various environmental conditions and analyzed from the viewpoint of self-affinity. The growth behavior can be described by the Eden model in favorable conditions, and by DLA in unfavorable conditions.

  5. Xanthomonas oryzae pv. oryzae TALE proteins recruit OsTFIIAγ1 to compensate for the absence of OsTFIIAγ5 in bacterial blight in rice.

    Science.gov (United States)

    Ma, Wenxiu; Zou, Lifang; Ji, Zhiyuan; Xu, Xiameng; Xu, Zhengyin; Yang, Yangyang; Alfano, James R; Chen, Gongyou

    2018-04-28

    Xanthomonas oryzae pv. oryzae (Xoo), causal agent of bacterial blight (BB) of rice, uses transcription activator-like effectors (TALEs) to interact with the basal transcription factor gama subunit OsTFIIAγ5 (Xa5) and activates transcription of host genes. However, how OsTFIIAγ1, the other OsTFIIAγ protein, functions in the presence of TALEs remains unclear. In this study, we show that OsTFIIAγ1 plays a compensatory role in the absence of Xa5. The expression of OsTFIIAγ1, which is activated by TALE PthXo7, increased the expression of host genes targeted by avirulent and virulent TALEs. Defective OsTFIIAγ1 rice lines showed reduced expression of the TALE-targeted susceptibility (S) genes, OsSWEET11 and OsSWEET14, which resulted in increased BB resistance. Selected TALEs (PthXo1, AvrXa7, and AvrXa27) were evaluated for interactions with OsTFIIAγ1, Xa5 and xa5 (naturally-occurring mutant form of Xa5) using biomolecular fluorescence complementation (BiFC) and microscale thermophoresis (MST). BiFC and MST demonstrated that the three TALEs bind Xa5 and OsTFIIAγ1 with a stronger affinity than xa5. These results provide insight into the complex roles of OsTFIIAγ1 and OsTFIIAγ5 in TALE-mediated host gene transcription. This article is protected by copyright. All rights reserved. © 2018 BSPP and John Wiley & Sons Ltd.

  6. Immobilization of Isolated Lipase From Moldy Copra (Aspergillus Oryzae)

    OpenAIRE

    Dali, Seniwati; Patong, A. B. D. Rauf; Jalaluddin, M. Noor; Pirman; Hamzah, Baharuddin

    2011-01-01

    Enzyme immobilization is a recovery technique that has been studied in several years, using support as a media to help enzyme dissolutions to the reaction substrate. Immobilization method used in this study was adsorption method, using specific lipase from Aspergillus oryzae. Lipase was partially purified from the culture supernatant of Aspergillus oryzae. Enzyme was immobilized by adsorbed on silica gel. Studies on free and immobilized lipase systems for determination of optimum pH, optimum ...

  7. Antibiotic effective against Saccharomyces produced by Aspergillus oryzae

    Energy Technology Data Exchange (ETDEWEB)

    Nakata, H.; Sakai, T.; Takeda, M.; Tsukahara, T.

    1980-01-01

    Production of an antibiotic effective against Saccharomyces cerevisiae was investigated in 85 strains of Aspergillus oryzae, isolated from commercial koji molds. The antibiotic was produced by 50 strains. A. oryzae was cultivated at 30 degrees for 15-20 days in koji extract. The crude preparation was obtained by precipitation from the culture filtrate with EtOH, MeOH, or Me/sub 2/CO.

  8. Detailed analysis of targeted gene mutations caused by the Platinum-Fungal TALENs in Aspergillus oryzae RIB40 strain and a ligD disruptant.

    Science.gov (United States)

    Mizutani, Osamu; Arazoe, Takayuki; Toshida, Kenji; Hayashi, Risa; Ohsato, Shuichi; Sakuma, Tetsushi; Yamamoto, Takashi; Kuwata, Shigeru; Yamada, Osamu

    2017-03-01

    Transcription activator-like effector nucleases (TALENs), which can generate DNA double-strand breaks at specific sites in the desired genome locus, have been used in many organisms as a tool for genome editing. In Aspergilli, including Aspergillus oryzae, however, the use of TALENs has not been validated. In this study, we performed genome editing of A. oryzae wild-type strain via error of nonhomologous end-joining (NHEJ) repair by transient expression of high-efficiency Platinum-Fungal TALENs (PtFg TALENs). Targeted mutations were observed as various mutation patterns. In particular, approximately half of the PtFg TALEN-mediated deletion mutants had deletions larger than 1 kb in the TALEN-targeting region. We also conducted PtFg TALEN-based genome editing in A. oryzae ligD disruptant (ΔligD) lacking the ligD gene involved in the final step of the NHEJ repair and found that mutations were still obtained as well as wild-type. In this case, the ratio of the large deletions reduced compared to PtFg TALEN-based genome editing in the wild-type. In conclusion, we demonstrate that PtFg TALENs are sufficiently functional to cause genome editing via error of NHEJ in A. oryzae. In addition, we reveal that genome editing using TALENs in A. oryzae tends to cause large deletions at the target region, which were partly suppressed by deletion of ligD. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  9. Effect of culture medium on polymer production and temperature on recovery of polymer produced from newly identified Rhyzopus oryzae ST29

    Directory of Open Access Journals (Sweden)

    Tipparat Hongpattarakere

    2008-04-01

    Full Text Available Thermotolerant fungal isolate ST29 was identified by observing on cell morphology and molecular technique based on internal transcribed spacer (ITS gene to be Rhizopus oryzae. Among four culture media tested, the strain exhibited the highest growth in yeast malt extract (YM medium (4.87 g/l, followed by Sabouraud dextrose broth (SDB (4.25 g/l, potato dextrose broth (PDB (4.10 g/l and palm oil mill effluent (POME (3.29 g/l, respectively, after 4 days cultivation at 45oC. However, the strain was found to produce polymer only in POME medium at 45oC, but not in the three synthetic media tested. Effect of temperature on separation of the biopolymer produced by this fungal strain was studied by incubating the culture broth in water bath with temperatures in the range of room temperature to 70oC. The biopolymer was recovered by filtration, centrifugation, and precipitation by adding 4 volumes of 95% ethanol, then freeze-drying. These temperatures therefore had no influence on the biopolymer yields (5.58-5.78 g/l or on biomass yields (2.90-3.29 g/l.

  10. Differentiation of Clinically Relevant mucorales Rhizopus microsporus and R. arrhizus by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS)

    NARCIS (Netherlands)

    Dolatabadi, S.; Kolecka, A.; Versteeg, Matthijs; de Hoog, Sybren G; Boekhout, Teun

    This study addresses the usefulness of Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) for reliable identification of the two most frequently occuring clinical species of Rhizopus, namely R. arrhizus with its two varieties arrhizus and delemar and R.

  11. Identification of Pectin Degrading Enzymes Secreted by Xanthomonas oryzae pv. oryzae and Determination of Their Role in Virulence on Rice

    OpenAIRE

    Tayi, Lavanya; Maku, Roshan V.; Patel, Hitendra Kumar; Sonti, Ramesh V.

    2016-01-01

    Xanthomonas oryzae pv.oryzae (Xoo) causes the serious bacterial blight disease of rice. Xoo secretes a repertoire of plant cell wall degrading enzymes (CWDEs) like cellulases, xylanases, esterases etc., which act on various components of the rice cell wall. The major cellulases and xylanases secreted by Xoo have been identified and their role in virulence has been determined. In this study, we have identified some of the pectin degrading enzymes of Xoo and assessed their role in virulence. Bi...

  12. Connexin mutants and cataracts

    Directory of Open Access Journals (Sweden)

    Eric C Beyer

    2013-04-01

    Full Text Available The lens is a multicellular, but avascular tissue that must stay transparent to allow normal transmission of light and focusing of it on the retina. Damage to lens cells and/or proteins can cause cataracts, opacities that disrupt these processes. The normal survival of the lens is facilitated by an extensive network of gap junctions formed predominantly of connexin46 and connexin50. Mutations of the genes that encode these connexins (GJA3 and GJA8 have been identified and linked to inheritance of cataracts in human families and mouse lines. In vitro expression studies of several of these mutants have shown that they exhibit abnormalities that may lead to disease. Many of the mutants reduce or modify intercellular communication due to channel alterations (including loss of function or altered gating or due to impaired cellular trafficking which reduces the number of gap junction channels within the plasma membrane. However, the abnormalities detected in studies of other mutants suggest that they cause cataracts through other mechanisms including gain of hemichannel function (leading to cell injury and death and formation of cytoplasmic accumulations (that may act as light scattering particles. These observations and the anticipated results of ongoing studies should elucidate the mechanisms of cataract development due to mutations of lens connexins and abnormalities of other lens proteins. They may also contribute to our understanding of the mechanisms of disease due to connexin mutations in other tissues.

  13. Crystallization and preliminary crystallographic studies of LipA, a secretory lipase/esterase from Xanthomonas oryzae pv. oryzae

    Energy Technology Data Exchange (ETDEWEB)

    Aparna, Gudlur; Chatterjee, Avradip; Jha, Gopaljee; Sonti, Ramesh V.; Sankaranarayanan, Rajan, E-mail: sankar@ccmb.res.in [Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007 (India)

    2007-08-01

    The crystallization and preliminary crystallographic studies of LipA, a lipase/esterase secreted by X. oryzae pv. oryzae during its infection of rice plants, are reported. Xanthomonas oryzae pv. oryzae is the causal agent of bacterial leaf blight, a serious disease of rice. Several enzymes that are secreted through the type II secretion system of this bacterium play an important role in the plant–microbe interaction, being important for virulence and also being able to induce potent host defence responses. One of these enzymes is a secretory lipase/esterase, LipA, which shows a very weak homology to other bacterial lipases and gives a positive tributyrin plate assay. In this study, LipA was purified from the culture supernatant of an overexpressing clone of X. oryzae pv. oryzae and two types of crystals belonging to space group C2 but with two different unit-cell parameters were obtained using the hanging-drop vapour-diffusion method. Type I crystals diffract to a maximum resolution of 1.89 Å and have unit-cell parameters a = 93.1, b = 62.3, c = 66.1 Å, β = 90.8°. Type II crystals have unit-cell parameters a = 103.6, b = 54.6, c = 66.3 Å, β = 92.6° and diffract to 1.86 Å. Solvent-content analysis shows one monomer in the asymmetric unit in both the crystal forms.

  14. First report of wheat blast caused by magnaporthe oryzae pathotype triticum in Bangladesh

    Science.gov (United States)

    Wheat blast or ‘brusone’, caused by the ascomycetous fungus Magnaporthe oryzae B.C. Couch (synonym Pyricularia oryzae Cavara), was first identified in 1985 in Brazil. M. oryzae is composed of a range of morphologically identical but genetically different host-specific pathotypes that are specialized...

  15. Functional and transcriptomic analysis of the key unfolded protein response transcription factor HacA in Aspergillus oryzae.

    Science.gov (United States)

    Zhou, Bin; Xie, Jingyi; Liu, Xiaokai; Wang, Bin; Pan, Li

    2016-11-15

    HacA is a conserved basic leucine zipper transcription factor that serves as the master transcriptional regulator in the unfolded protein response (UPR). To comprehensively evaluate the role of HacA in Aspergillus oryzae, a homokaryotic hacA disruption mutant (HacA-DE) and a strain that expressed a constitutively active form of HacA (HacA-CA) were successfully generated, and transcriptome analyses of these mutants were performed. Growth and phenotypic profiles demonstrated that hyphal growth and sporulation were impaired in the HacA-DE and HacA-CA strains that were grown on complete and minimal media, and the growth impairment was more pronounced for the HacA-CA strain. Compared with a wild-type (WT) strain, the transcriptome results indicated that differentially expressed genes in these mutants mainly fell into four categories: the protein secretory pathway, amino acid metabolism, lipid metabolism, and carbohydrate metabolism. Furthermore, we identified 80 and 36 genes of the secretory pathway whose expression significantly differed in the HacA-CA strain (compared with the WT and HacA-DE strains) and HacA-DE strain (compared with the WT strain), respectively, which mostly belonged to protein folding/UPR, glycosylation, and vesicle transport processes. Both the HacA-CA and HacA-DE strains exhibited reduced expression of extracellular enzymes, especially amylolytic enzymes, which resulted from the activation of the repression under secretion stress mechanism in response to endoplasmic reticulum stress. Collectively, our results suggest that the function of HacA is important not only for UPR induction, but also for growth and fungal physiology, as it serves to reduce secretion stress in A. oryzae. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Asp30 of Aspergillus oryzae cutinase CutL1 is involved in the ionic interaction with fungal hydrophobin RolA.

    Science.gov (United States)

    Terauchi, Yuki; Kim, Yoon-Kyung; Tanaka, Takumi; Nanatani, Kei; Takahashi, Toru; Abe, Keietsu

    2017-07-01

    Aspergillus oryzae hydrophobin RolA adheres to the biodegradable polyester polybutylene succinate-co-adipate (PBSA) and promotes PBSA degradation by interacting with A. oryzae polyesterase CutL1 and recruiting it to the PBSA surface. In our previous studies, we found that positively charged amino acid residues (H32, K34) of RolA and negatively charged residues (E31, D142, D171) of CutL1 are important for the cooperative ionic interaction between RolA and CutL1, but some other charged residues in the triple mutant CutL1-E31S/D142S/D171S are also involved. In the present study, on the basis of the 3D-structure of CutL1, we hypothesized that D30 is also involved in the CutL1-RolA interaction. We substituted D30 with serine and performed kinetic analysis of the interaction between wild-type RolA and the single mutant CutL1-D30S or quadruple mutant CutL1-D30S/E31S/D142S/D171S by using quartz crystal microbalance. Our results indicate that D30 is a novel residue involved in the ionic interaction between RolA and CutL1.

  17. In planta gene expression analysis of Xanthomonas oryzae pathovar oryzae, African strain MAI1

    Directory of Open Access Journals (Sweden)

    Verdier Valérie

    2010-06-01

    Full Text Available Abstract Background Bacterial leaf blight causes significant yield losses in rice crops throughout Asia and Africa. Although both the Asian and African strains of the pathogen, Xanthomonas oryzae pv. oryzae (Xoo, induce similar symptoms, they are nevertheless genetically different, with the African strains being more closely related to the Asian X. oryzae pv. oryzicola (Xoc. Results Changes in gene expression of the African Xoo strain MAI1 in the susceptible rice cultivar Nipponbare were profiled, using an SSH Xoo DNA microarray. Microarray hybridization was performed comparing bacteria recovered from plant tissues at 1, 3, and 6 days after inoculation (dai with bacteria grown in vitro. A total of 710 bacterial genes were found to be differentially expressed, with 407 up-regulated and 303 down-regulated. Expression profiling indicated that less than 20% of the 710 bacterial transcripts were induced in the first 24 h after inoculation, whereas 63% were differentially expressed at 6 dai. The 710 differentially expressed genes were one-end sequenced. 535 sequences were obtained from which 147 non-redundant sequences were identified. Differentially expressed genes were related to metabolism, secretion and transport, pathogen adherence to plant tissues, plant cell-wall degradation, IS elements, and virulence. In addition, various other genes encoding proteins with unknown function or showing no similarity to other proteins were also induced. The Xoo MAI1 non-redundant set of sequences was compared against several X. oryzae genomes, revealing a specific group of genes that was present only in MAI1. Numerous IS elements were also found to be differentially expressed. Quantitative real-time PCR confirmed 86% of the identified profile on a set of 14 genes selected according to the microarray analysis. Conclusions This is the first report to compare the expression of Xoo genes in planta across different time points during infection. This work shows that

  18. Cell wall α-1,3-glucan prevents α-amylase adsorption onto fungal cell in submerged culture of Aspergillus oryzae.

    Science.gov (United States)

    Zhang, Silai; Sato, Hiroki; Ichinose, Sakurako; Tanaka, Mizuki; Miyazawa, Ken; Yoshimi, Akira; Abe, Keietsu; Shintani, Takahiro; Gomi, Katsuya

    2017-07-01

    We have previously reported that α-amylase (Taka-amylase A, TAA) activity disappears in the later stage of submerged Aspergillus oryzae culture as a result of TAA adsorption onto the cell wall. Chitin, one of the major components of the cell wall, was identified as a potential factor that facilitates TAA adsorption. However, TAA adsorption only occurred in the later stage of cultivation, although chitin was assumed to be sufficiently abundant in the cell wall regardless of the submerged culture period. This suggested the presence a factor that inhibits TAA adsorption to the cell wall in the early stage of cultivation. In the current study, we identified α-1,3-glucan as a potential inhibiting factor for TAA adsorption. We constructed single, double, and triple disruption mutants of three α-1,3-glucan synthase genes (agsA, agsB, and agsC) in A. oryzae. Growth characteristics and cell wall component analysis of these disruption strains showed that AgsB plays a major role in α-1,3-glucan synthesis. In the ΔagsB mutant, TAA was adsorbed onto the mycelium in all stages of cultivation (early and later), and the ΔagsB mutant cell walls had a significantly high capacity for TAA adsorption. Moreover, the α-1,3-glucan content of the cell wall prepared from the wild-type strain in the later stage of cultivation was markedly reduced compared with that in the early stage. These results suggest that α-1,3-glucan is a potential inhibiting factor for TAA adsorption onto the cell wall component, chitin, in the early stage of submerged culture in A. oryzae. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  19. Photorepair mutants of Arabidopsis

    International Nuclear Information System (INIS)

    Jiang, C.Z.; Yee, J.; Mitchell, D.L.; Britt, A.B.

    1997-01-01

    UV radiation induces two major DNA damage products, the cyclobutane pyrimidine dimer (CPD) and, at a lower frequency, the pyrimidine (6-4) pyrimidinone dimer (6-4 product). Although Escherichia coli and Saccharomyces cerevisiae produce a CPD-specific photolyase that eliminates only this class of dimer, Arabidopsis thaliana, Drosophila melanogaster, Crotalus atrox, and Xenopus laevis have recently been shown to photoreactivate both CPDs and 6-4 products. We describe the isolation and characterization of two new classes of mutants of Arabidopsis, termed uvr2 and uvr3, that are defective in the photoreactivation of CPDs and 6-4 products, respectively. We demonstrate that the CPD photolyase mutation is genetically linked to a DNA sequence encoding a type II (metazoan) CPD photolyase. In addition, we are able to generate plants in which only CPDs or 6-4 products are photoreactivated in the nuclear genome by exposing these mutants to UV light and then allowing them to repair one or the other class of dimers. This provides us with a unique opportunity to study the biological consequences of each of these two major UV-induced photoproducts in an intact living system

  20. Construindo Marcas Mutantes

    Directory of Open Access Journals (Sweden)

    Elizete De Azevedo Kreutz

    2012-09-01

    Full Text Available O presente artigo é o resultado de estudos realizados desde 2000 e busca instrumentalizar os proñssionals para a construção de Marcas Mutantes, que é   uma tendência contemporânea nas estratégias comunicacionais e de branding. Embora esta estratégia ainda não esteja consolidada, observamos que a mesma tem obtido um crescimento constante e tem sido adotadas pelas mais diferentes categorias de marcas e não apenas por aquelas direcionadas aos jovens, ao esporte, ao entretenimento, como era no principia. Com base na Hermenêutica de Profundidade de Thompson (1995, alicerçada nas pesquisas bibliográficas, de intemet, entrevistas e análise semiótica, desenhamos um método de construção de Marcas Mutantes dividido em sete fases. Como resultado, esperamos que este estudo possa auxiliar na compreensão dos processos envolvidos, ao mesmo tempo que provoque a discussão sobreo mesmo e, por consequência, o seu aprimoramento.

  1. Morphological and molecular characterization of fungal pathogen, Magnaphorthe oryzae

    International Nuclear Information System (INIS)

    Hasan, Nor’Aishah; Rafii, Mohd Y.; Rahim, Harun A.; Ali, Nusaibah Syd; Mazlan, Norida; Abdullah, Shamsiah

    2016-01-01

    Rice is arguably the most crucial food crops supplying quarter of calories intake. Fungal pathogen, Magnaphorthe oryzae promotes blast disease unconditionally to gramineous host including rice species. This disease spurred an outbreaks and constant threat to cereal production. Global rice yield declining almost 10-30% including Malaysia. As Magnaphorthe oryzae and its host is model in disease plant study, the rice blast pathosystem has been the subject of intense interest to overcome the importance of the disease to world agriculture. Therefore, in this study, our prime objective was to isolate samples of Magnaphorthe oryzae from diseased leaf obtained from MARDI Seberang Perai, Penang, Malaysia. Molecular identification was performed by sequences analysis from internal transcribed spacer (ITS) region of nuclear ribosomal RNA genes. Phylogenetic affiliation of the isolated samples were analyzed by comparing the ITS sequences with those deposited in the GenBank database. The sequence of the isolate demonstrated at least 99% nucleotide identity with the corresponding sequence in GenBank for Magnaphorthe oryzae. Morphological observed under microscope demonstrated that the structure of conidia followed similar characteristic as M. oryzae. Finding in this study provide useful information for breeding programs, epidemiology studies and improved disease management

  2. Secretome of Aspergillus oryzae in Shaoxing rice wine koji.

    Science.gov (United States)

    Zhang, Bo; Guan, Zheng-Bing; Cao, Yu; Xie, Guang-Fa; Lu, Jian

    2012-04-16

    Shaoxing rice wine is the most famous and representative Chinese rice wine. Aspergillus oryzae SU16 is used in the manufacture of koji, the Shaoxing rice wine starter culture. In the current study, a comprehensive analysis of the secretome profile of A. oryzae SU16 in Shaoxing rice wine koji was performed for the first time. The proteomic analysis for the identification of the secretory proteins was done using two-dimensional electrophoresis combined with matrix-assisted laser desorption/ionization-tandem time of flight mass spectrometry based on the annotated A. oryzae genome sequence. A total of 41 unique proteins were identified from the secretome. These proteins included 17 extracellular proteins following the classical secretory pathway, and 10 extracellular proteins putatively secreted by the non-classical secretory pathway. The present secretome profile greatly differed from previous reports on A. oryzae growing in other solid-state nutrient sources. Several new secretory or putative secretory proteins were also found. These proteomic data will significantly aid the advancement of research on the secretome of A. oryzae, especially in solid-state cultures, and in elucidating the production process mechanism of Shaoxing rice wine koji. The findings may promote the technological development and innovation of the Shaoxing rice wine industry. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Morphological and molecular characterization of fungal pathogen, Magnaphorthe oryzae

    Science.gov (United States)

    Hasan, Nor'Aishah; Rafii, Mohd Y.; Rahim, Harun A.; Ali, Nusaibah Syd; Mazlan, Norida; Abdullah, Shamsiah

    2016-02-01

    Rice is arguably the most crucial food crops supplying quarter of calories intake. Fungal pathogen, Magnaphorthe oryzae promotes blast disease unconditionally to gramineous host including rice species. This disease spurred an outbreaks and constant threat to cereal production. Global rice yield declining almost 10-30% including Malaysia. As Magnaphorthe oryzae and its host is model in disease plant study, the rice blast pathosystem has been the subject of intense interest to overcome the importance of the disease to world agriculture. Therefore, in this study, our prime objective was to isolate samples of Magnaphorthe oryzae from diseased leaf obtained from MARDI Seberang Perai, Penang, Malaysia. Molecular identification was performed by sequences analysis from internal transcribed spacer (ITS) region of nuclear ribosomal RNA genes. Phylogenetic affiliation of the isolated samples were analyzed by comparing the ITS sequences with those deposited in the GenBank database. The sequence of the isolate demonstrated at least 99% nucleotide identity with the corresponding sequence in GenBank for Magnaphorthe oryzae. Morphological observed under microscope demonstrated that the structure of conidia followed similar characteristic as M. oryzae. Finding in this study provide useful information for breeding programs, epidemiology studies and improved disease management.

  4. Cell biology of the Koji mold Aspergillus oryzae.

    Science.gov (United States)

    Kitamoto, Katsuhiko

    2015-01-01

    Koji mold, Aspergillus oryzae, has been used for the production of sake, miso, and soy sauce for more than one thousand years in Japan. Due to the importance, A. oryzae has been designated as the national micro-organism of Japan (Koku-kin). A. oryzae has been intensively studied in the past century, with most investigations focusing on breeding techniques and developing methods for Koji making for sake brewing. However, the understanding of fundamental biology of A. oryzae remains relatively limited compared with the yeast Saccharomyces cerevisiae. Therefore, we have focused on studying the cell biology including live cell imaging of organelles, protein vesicular trafficking, autophagy, and Woronin body functions using the available genomic information. In this review, I describe essential findings of cell biology of A. oryzae obtained in our study for a quarter of century. Understanding of the basic biology will be critical for not its biotechnological application, but also for an understanding of the fundamental biology of other filamentous fungi.

  5. Chitosan Mediates Germling Adhesion in Magnaporthe oryzae and Is Required for Surface Sensing and Germling Morphogenesis

    Science.gov (United States)

    Geoghegan, Ivey A.; Gurr, Sarah J.

    2016-01-01

    The fungal cell wall not only plays a critical role in maintaining cellular integrity, but also forms the interface between fungi and their environment. The composition of the cell wall can therefore influence the interactions of fungi with their physical and biological environments. Chitin, one of the main polysaccharide components of the wall, can be chemically modified by deacetylation. This reaction is catalyzed by a family of enzymes known as chitin deacetylases (CDAs), and results in the formation of chitosan, a polymer of β1,4-glucosamine. Chitosan has previously been shown to accumulate in the cell wall of infection structures in phytopathogenic fungi. Here, it has long been hypothesized to act as a 'stealth' molecule, necessary for full pathogenesis. In this study, we used the crop pathogen and model organism Magnaporthe oryzae to test this hypothesis. We first confirmed that chitosan localizes to the germ tube and appressorium, then deleted CDA genes on the basis of their elevated transcript levels during appressorium differentiation. Germlings of the deletion strains showed loss of chitin deacetylation, and were compromised in their ability to adhere and form appressoria on artificial hydrophobic surfaces. Surprisingly, the addition of exogenous chitosan fully restored germling adhesion and appressorium development. Despite the lack of appressorium development on artificial surfaces, pathogenicity was unaffected in the mutant strains. Further analyses demonstrated that cuticular waxes are sufficient to over-ride the requirement for chitosan during appressorium development on the plant surface. Thus, chitosan does not have a role as a 'stealth' molecule, but instead mediates the adhesion of germlings to surfaces, thereby allowing the perception of the physical stimuli necessary to promote appressorium development. This study thus reveals a novel role for chitosan in phytopathogenic fungi, and gives further insight into the mechanisms governing

  6. Chitosan Mediates Germling Adhesion in Magnaporthe oryzae and Is Required for Surface Sensing and Germling Morphogenesis.

    Directory of Open Access Journals (Sweden)

    Ivey A Geoghegan

    2016-06-01

    Full Text Available The fungal cell wall not only plays a critical role in maintaining cellular integrity, but also forms the interface between fungi and their environment. The composition of the cell wall can therefore influence the interactions of fungi with their physical and biological environments. Chitin, one of the main polysaccharide components of the wall, can be chemically modified by deacetylation. This reaction is catalyzed by a family of enzymes known as chitin deacetylases (CDAs, and results in the formation of chitosan, a polymer of β1,4-glucosamine. Chitosan has previously been shown to accumulate in the cell wall of infection structures in phytopathogenic fungi. Here, it has long been hypothesized to act as a 'stealth' molecule, necessary for full pathogenesis. In this study, we used the crop pathogen and model organism Magnaporthe oryzae to test this hypothesis. We first confirmed that chitosan localizes to the germ tube and appressorium, then deleted CDA genes on the basis of their elevated transcript levels during appressorium differentiation. Germlings of the deletion strains showed loss of chitin deacetylation, and were compromised in their ability to adhere and form appressoria on artificial hydrophobic surfaces. Surprisingly, the addition of exogenous chitosan fully restored germling adhesion and appressorium development. Despite the lack of appressorium development on artificial surfaces, pathogenicity was unaffected in the mutant strains. Further analyses demonstrated that cuticular waxes are sufficient to over-ride the requirement for chitosan during appressorium development on the plant surface. Thus, chitosan does not have a role as a 'stealth' molecule, but instead mediates the adhesion of germlings to surfaces, thereby allowing the perception of the physical stimuli necessary to promote appressorium development. This study thus reveals a novel role for chitosan in phytopathogenic fungi, and gives further insight into the mechanisms

  7. PENGGUNAAN PROTEASE ASPERGILLUS sp. DAN RHIZOPUS sp. DENGAN KONSENTRASI YANG BERBEDA DALAM TAHAPAN UNHAIRING TERHADAP KUALITAS FISIK DAN LIMBAH CAIR PADA PENYAMAKAN KULIT DOMBA

    Directory of Open Access Journals (Sweden)

    Yunus Syafie

    2013-10-01

    Full Text Available Penelitian ini bertujuan untuk mengetahui aktivitas proteolitik yang dihasilkan jamur Aspergillus sp. dan Rhizopus sp. dalam tahapan unhairing (buang rambut pada proses penyamakan kulit domba serta pengaruh penggunaan dengan konsentrasi berbeda, terhadap kuat tarik, kemuluran, suhu kerut, dan kualitas limbah (pH, BOD, dan COD. Materi yang digunakan yaitu 15 lembar kulit domba awetan garam dibagi 2 bagian sepanjang garis lurus punggung sehingga diperoleh 30 lembar kulit, kulit dibagi secara acak menjadi 10 kelompok. Perlakuan terdiri dari dua belas kombinasi yaitu protease dari Aspergillus sp., Rhizopus sp. serta gabungan antara Aspergillus sp. dan Rhizopus sp. dengan konsentrasi protease 2% (P1, 2,5% (P2, 3% (P3, dan sebagai kontrol P0. Proses unhairing secara konvensional menggunakan bahan kimia Na2S (3% dan kapur Ca(OH2 6% dengan 3 ulangan. Sampel air limbah setelah proses unhairing diambil dan dibawa ke laboratorium untuk uji kualitas. Kulit diproses lebih lanjut menjadi kulit samak glazed. Data yang diperoleh dianalisis menggunakan Rancangan Acak Lengkap pola faktorial 3 x 4, apabila berbeda nyata dilakukan uji banding dengan uji Duncan’s new Multiple Range Test (DMRT. Hasil uji aktivitas proteolitik paling tinggi adalah gabungan antara protease dari Aspergillus sp. dan Rhizopus sp. yaitu sebesar 1.079,17 μM/ml/menit, sedangkan protease Aspergillus sp. dan Rhizopus sp. masing-masing memiliki aktivitas proteolitik sebesar 542,96 μM/ml/menit dan 392,89 μM/ml/menit. Hasil penelitian menunjukkan bahwa penggunaan protease dengan konsentrasi yang berbeda dapat memberikan efek yang positif terhadap kualitas fisik dan limbah cair proses unhairing kulit domba. Konsentrasi protease 2,5% dan 3% dapat meningkatkan nilai kuat tarik dan suhu kerut kulit domba serta menghasilkan kulit yang bersih tanpa ada rambut yang menempel dan struktur serabut kolagen terbuka. Perlakuan protease sangat potensial karena dapat menekan angka BOD dan COD limbah

  8. Direct suppression of a rice bacterial blight (Xanthomonas oryzae pv. oryzae) by monoterpene (S)-limonene.

    Science.gov (United States)

    Lee, Gun Woong; Chung, Moon-Soo; Kang, Mihyung; Chung, Byung Yeoup; Lee, Sungbeom

    2016-05-01

    Rice bacterial blight, caused by Xanthomonas oryzae pv. oryzae (Xoo), is a severe disease of rice plants. Upon pathogen infection, rice biosynthesizes phytoalexins, including diterpenoids such as momilactones, phytocassanes, and oryzalexins. However, information on headspace volatiles in response to Xoo infection is limited. We have examined headspace volatile terpenes, induced by the infection of Xoo, and investigated their biological roles in the rice plant. Monoterpenes α-thujene, α-pinene, sabinene, myrcene, α-terpene, and (S)-limonene and sesquiterpenes cyclosativene, α-copaene, and β-elemene were detected from 1-week-old Xoo-infected rice seedlings, by solid-phase microextraction-gas chromatography-mass spectrometry. All monoterpenes were constitutively released from rice seedlings before Xoo infection. However, (S)-limonene emission was further elicited after exposure of the seedlings to Xoo in coincidence with upregulation of limonene synthase gene (OsTPS20) transcripts. Only the stereospecific (S)-limonene [and not (R)-limonene or other monoterpenes] severely inhibited Xoo growth, as confirmed by disc diffusion and liquid culture assays. Rice seedlings showed suppressed pathogenic symptoms suggestive of resistance to Xoo infection after foliar treatment with (S)-limonene. Collectively, our findings suggest that (S)-limonene is a volatile phytoanticipin, which plays a significant role in suppressing Xoo growth in rice seedlings.

  9. PENENTUAN PATOTIPE DAN KERAGAMAN GENETIK Xanthomonas oryzae pv. oryzae PADA TANAMAN PADI DI WILAYAH KARESIDENAN BANYUMAS

    Directory of Open Access Journals (Sweden)

    Heru Adi Djatmiko

    2011-11-01

    Full Text Available One of the major diseases of rice paddy fields in Indonesia and the Asian countries is bacterial leaf blight or kresek caused by X. oryzae pv. oryzae (Xoo. Losses caused by the disease in Indonesia reached 70–80%, in India reached 74–81%, and Japan reached 20–50%, thus causing great losses in the economy. The objectives of that research were: 1 Characterize Xoo from Karesidenan Banyumas; 2 To study of the amount of damage and AUDPC (the area under disease progress curve of bacterial leaf blight disease at Karesidenan Banyumas; 3 To obtain of Xoo pathotype by using the test varieties; 4 To obtaining genetic diversity of Xoo that found in Banjarnegara, Purbalingga, Banyumas, Cilacap dan Kebumen region. Research was carried out in several stages: isolation and characterization of Xoo from Barlingmascakeb region, testing of Xoo with five varieties testing, assesment of disease intensity of bacterial leaf blight and AUDPC in the field, and testing the genetic diversity of Xoo. The results showed that pathogen of bacterial blight on rice is Xoo characterized yellow colour of colonies on SPA medium, negative gram reaction, catalase positive, oxidase negative, negative growth at 0.1% TZC, negative starch hydrolisis , and resistance to 0.001% Cu(NO32 positive. Xoo pathotype isolats found in Banjarnegara was pathotype X, Cilacap were pathotype I and II and Purbalingga was pathotype II. Eighteen of Xoo from Karesidenan Banyumas (Banjarnegara, Purbalingga, Banyumas, Cilacap and Kebumen of RAPD differ one from the others.

  10. PATHOTYPE GROUPING OF Xanthomonas oryzae pv. oryzae ISOLATES FROM SOUTH SULAWESI AND SOUTHEAST SULAWESI

    Directory of Open Access Journals (Sweden)

    Andi Khaeruni

    2013-06-01

    Full Text Available Bacterial leaf blight caused by Xanthomonas oryzae pv. oryzae (Xoo is an important rice disease, and has caused significant economic losses. This research aimed to determine the pathotype grouping and the distribution of Xoo isolates of South and Southeast Sulawesi. In order to obtain the information, 61 Xoo isolates of South Sulawesi and 29 isolates of Southeast Sulawesi were evaluated for their pathotype grouping against 5 diffential varieties. Research results showed that in South Sulawesi there were 2 pathotype groups, namely pathotype IV (32.79% and pathotype VIII(67.21%. Pathotype VIII was widely distributed over the Western and Central areas of South Sulawesi, whereas pathotype IV was widely distributed over the Southern area. In Southeast Sulawesi, it was found 5 pathotypes, namely pathotypes IV (27.58%, VI (10.34%, VIII (13.79%, IX (20.68%, and X (27.58%, with a limited and scattered distribution pattern on several areas. These results indicate that Xoo pathotype groups in South Sulawesi and Southeast Sulawesi are varied and tend to sift to more virulent pathotypes.

  11. Pathotype profile of Xanthomonas oryzae pv. oryzae isolates from North Sumatera

    Science.gov (United States)

    Noer, Z.; Hasanuddin; Lisnawita; Suryanto, D.

    2018-02-01

    The Bacterial blight disease caused by Xanthomonas oryzae pv. oryzae (Xoo) is one of the most important diseases and has caused crop failure in rice crops. This pathogen infects the leaves in all plant growth phases. The purpose of this study is to investigation 10 Xoo isolates pathotype obtained from North Sumatra based on their interactions with 10 near-isogenic rice lines (NIL) of IRRI. The results showed that there are 6 pathotypes of virulence in North Sumatra, they are; pathotype I with incompatible interaction to all Xa genes, pathotype II with compatible interaction to Xa1 and Xa3 genes, while it has incompatible interaction to other genes, pathotype III with compatible interaction to Xa1, Xa5, Xa7, Xa8, Xa10 and Xa11 genes, but it has incompatible interaction to other genes, pathotype IV with compatible interaction to all Xa genes, pathotype V with compatible interaction to Xa1 gene and incompatible interaction to other genes, and pathotype VI with compatible interaction to Xa3 gene and incompatible interaction to other genes. Based on the resistant genes in each individual Xa2, Xa4, and Xa21 genes are the combination of Xa genes which are most suitable for use in the development of rice cultivars in North Sumatra.

  12. A reductive aminase from Aspergillus oryzae

    Science.gov (United States)

    Aleku, Godwin A.; France, Scott P.; Man, Henry; Mangas-Sanchez, Juan; Montgomery, Sarah L.; Sharma, Mahima; Leipold, Friedemann; Hussain, Shahed; Grogan, Gideon; Turner, Nicholas J.

    2017-10-01

    Reductive amination is one of the most important methods for the synthesis of chiral amines. Here we report the discovery of an NADP(H)-dependent reductive aminase from Aspergillus oryzae (AspRedAm, Uniprot code Q2TW47) that can catalyse the reductive coupling of a broad set of carbonyl compounds with a variety of primary and secondary amines with up to >98% conversion and with up to >98% enantiomeric excess. In cases where both carbonyl and amine show high reactivity, it is possible to employ a 1:1 ratio of the substrates, forming amine products with up to 94% conversion. Steady-state kinetic studies establish that the enzyme is capable of catalysing imine formation as well as reduction. Crystal structures of AspRedAm in complex with NADP(H) and also with both NADP(H) and the pharmaceutical ingredient (R)-rasagiline are reported. We also demonstrate preparative scale reductive aminations with wild-type and Q240A variant biocatalysts displaying total turnover numbers of up to 32,000 and space time yields up to 3.73 g l-1 d-1.

  13. Isozyme differences in barley mutants

    Energy Technology Data Exchange (ETDEWEB)

    AI-Jibouri, A A.M.; Dham, K M [Department of Botany, Nuclear Research Centre, Baghdad (Iraq)

    1990-01-01

    Full text: Thirty mutants (M{sub 11}) of barley (Hordeum vulgare L.) induced by physical and chemical mutagens were analysed for isozyme composition using polyacrylamide gel electrophoresis. Results show that these mutants were different in the isozymes leucine aminopeptidase, esterase and peroxidase. The differences included the number of forms of each enzyme, relative mobility value and their intensity on the gel. Glutamate oxaloacetate transaminase isozyme was found in six molecular forms and these forms were similar in all mutants. (author)

  14. Isozyme differences in barley mutants

    International Nuclear Information System (INIS)

    AI-Jibouri, A.A.M.; Dham, K.M.

    1990-01-01

    Full text: Thirty mutants (M 11 ) of barley (Hordeum vulgare L.) induced by physical and chemical mutagens were analysed for isozyme composition using polyacrylamide gel electrophoresis. Results show that these mutants were different in the isozymes leucine aminopeptidase, esterase and peroxidase. The differences included the number of forms of each enzyme, relative mobility value and their intensity on the gel. Glutamate oxaloacetate transaminase isozyme was found in six molecular forms and these forms were similar in all mutants. (author)

  15. Genetic Analysis and Mapping of TWH Gene in Rice Twisted Hull Mutant

    Directory of Open Access Journals (Sweden)

    Jin-bo LI

    2009-03-01

    Full Text Available A mutant with twisted hulls was found in a breeding population of rice (Oryza sativa L.. The mutant shows less grain weight and inferior grain quality in addition to twisted hulls. Genetic analysis indicated that the phenotype of mutant was controlled by a single recessive gene (temporarily designated as TWH. To map the TWH gene, an F2 population was generated by crossing the twh mutant to R725, an indica rice variety with normal hulls. For bulked segregant analysis, the bulk of mutant plants was prepared by mixing equal amount of plant tissue from 10 twisted-hull plants and the bulk of normal plants was obtained by pooling equal amount tissue of 10 normal-hull plants. Two hundred and seven pairs of simple sequence repeat (SSR primers, which are distributed on 12 rice chromosomes, were used for polymorphism analysis of the parents and the two bulks. The TWH locus was initially mapped close to the SSR marker RM526 on chromosome 2. Therefore, further mapping was performed using 50 pairs of SSR primers around the marker RM526. The TWH was delimited between the SSR markers RM14128 and RM208 on the long arm of chromosome 2 at the genetic distances of 1.4 cM and 2.7 cM, respectively. These results provide the foundation for further fine mapping, cloning and functional analysis of the TWH gene.

  16. The Sequences of 1504 Mutants in the Model Rice Variety Kitaake Facilitate Rapid Functional Genomic Studies.

    Science.gov (United States)

    Li, Guotian; Jain, Rashmi; Chern, Mawsheng; Pham, Nikki T; Martin, Joel A; Wei, Tong; Schackwitz, Wendy S; Lipzen, Anna M; Duong, Phat Q; Jones, Kyle C; Jiang, Liangrong; Ruan, Deling; Bauer, Diane; Peng, Yi; Barry, Kerrie W; Schmutz, Jeremy; Ronald, Pamela C

    2017-06-01

    The availability of a whole-genome sequenced mutant population and the cataloging of mutations of each line at a single-nucleotide resolution facilitate functional genomic analysis. To this end, we generated and sequenced a fast-neutron-induced mutant population in the model rice cultivar Kitaake ( Oryza sativa ssp japonica ), which completes its life cycle in 9 weeks. We sequenced 1504 mutant lines at 45-fold coverage and identified 91,513 mutations affecting 32,307 genes, i.e., 58% of all rice genes. We detected an average of 61 mutations per line. Mutation types include single-base substitutions, deletions, insertions, inversions, translocations, and tandem duplications. We observed a high proportion of loss-of-function mutations. We identified an inversion affecting a single gene as the causative mutation for the short-grain phenotype in one mutant line. This result reveals the usefulness of the resource for efficient, cost-effective identification of genes conferring specific phenotypes. To facilitate public access to this genetic resource, we established an open access database called KitBase that provides access to sequence data and seed stocks. This population complements other available mutant collections and gene-editing technologies. This work demonstrates how inexpensive next-generation sequencing can be applied to generate a high-density catalog of mutations. © 2017 American Society of Plant Biologists. All rights reserved.

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

    DEFF Research Database (Denmark)

    Vongsangnak, Wanwipa; Olsen, Peter; Hansen, Kim

    2008-01-01

    Background: Since ancient times the filamentous fungus Aspergillus oryzae has been used in the fermentation industry for the production of fermented sauces and the production of industrial enzymes. Recently, the genome sequence of A. oryzae with 12,074 annotated genes was released but the number...... to a genome scale metabolic model of A. oryzae. Results: Our assembled EST sequences we identified 1,046 newly predicted genes in the A. oryzae genome. Furthermore, it was possible to assign putative protein functions to 398 of the newly predicted genes. Noteworthy, our annotation strategy resulted...... model was validated and shown to correctly describe the phenotypic behavior of A. oryzae grown on different carbon sources. Conclusion: A much enhanced annotation of the A. oryzae genome was performed and a genomescale metabolic model of A. oryzae was reconstructed. The model accurately predicted...

  18. The biosynthesis, structure and gelatinization properties of starches from wild and cultivated African rice species (Oryza barthii and Oryza glaberrima).

    Science.gov (United States)

    Wang, Kai; Wambugu, Peterson W; Zhang, Bin; Wu, Alex Chi; Henry, Robert J; Gilbert, Robert G

    2015-09-20

    The molecular structure and gelatinization properties of starches from domesticated African rice (Oryza glaberrima) and its wild progenitor (Oryza barthii) are determined and comparison made with Asian domesticated rice (Oryza sativa), the commonest commercial rice. This suggests possible enzymatic processes contributing to the unique traits of the African varieties. These have similar starch structures, including smaller amylose molecules, but larger amounts of amylose chains across the whole amylose chain-length distribution, and higher amylose contents, than O. sativa. They also show a higher proportion of two- and three-lamellae spanning amylopectin branch chains (degree of polymerization 34-100) than O. sativa, which contributes to their higher gelatinization temperatures. Fitting amylopectin chain-length distribution with a biosynthesis-based mathematical model suggests that the reason for this difference might be because O. glaberrima and O. barthii have more active SSIIIa and/or less active SBEIIb enzymes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. The Magnaporthe oryzae Alt A 1-like protein MoHrip1 binds to the plant plasma membrane.

    Science.gov (United States)

    Zhang, Yi; Liang, Yingbo; Dong, Yijie; Gao, Yuhan; Yang, Xiufen; Yuan, Jingjing; Qiu, Dewen

    2017-10-07

    MoHrip1, a protein isolated from Magnaporthe oryzae, belongs to the Alt A 1 (AA1) family. mohrip1 mRNA levels showed inducible expression throughout the infection process in rice. To determine the location of MoHrip1 in M. oryzae, a mohrip1-gfp mutant was generated. Fluorescence microscopy observations and western blotting analysis showed that MoHrip1 was both present in the secretome and abundant in the fungal cell wall. To obtain MoHrip1 protein, we carried out high-yield expression of MoHrip1 in Pichia pastoris. Treatment of tobacco plants with MoHrip1 induced the formation of necrosis, accumulation of reactive oxygen species and expression of several defense-related genes, as well as conferred disease resistance. By fusion to green fluorescent protein, we showed that MoHrip1 was able to bind to the tobacco and rice plant plasma membrane, causing rapid morphological changes at the cellular level, such as cell shrinkage and chloroplast disorganization. These findings indicate that MoHrip1 is a microbe-associated molecular pattern that is perceived by the plant immune system. This is the first study on an AA1 family protein that can bind to the plant plasma membrane. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Rhizopus-associated soft tissue infection in an immunocompetent air-conditioning technician after a road traffic accident: A case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Nada B. Rabie

    2012-02-01

    Full Text Available Summary: Rhinocerebral or sinopulmonary mucromycosis is a well-recognized human fungal infection found among immunocompromised and diabetic patients. However, the infection is rare among immunocompetent hosts. We are reporting the case of an adult immunocompetent male patient working as an air-conditioning technician. The patient was a victim of a road traffic accident (RTA and sustained multiple fractures in the proximal part of the left tibia, distal femur, and scapula. Two weeks postoperatively, Rhizopus microspores were isolated from an infected traumatic wound over the distal femur. Surgical debridement was performed, and the patient was started on amphotericin B. Occupational exposure history and workplace environmental sanitation are crucial for the prevention of this potentially fatal yet preventable infection. Keywords: Rhizopus, Immunocompetent, Air conditioning

  1. Caffeine degradation by Rhizopus delemar in packed bed column bioreactor using coffee husk as substrate Degradação de cafeína por Rhizopus delemar em biorreator de colunas usando casca de café como substrato

    Directory of Open Access Journals (Sweden)

    Cristiane Vanessa Tagliari

    2003-11-01

    Full Text Available Various microorganisms including bacteria, yeast and fungi can degrade caffeine. There are few publications about caffeine degradation pathway in filamentous fungi, mainly by solid-state fermentation (SSF. Studies were carried out on degradation of caffeine and their metabolites by filamentous fungi in SSF using coffee husk as substrate. The purpose of this work was to investigate the caffeine degradation pathway by Rhizopus delemar in packed bed column fermenter and to compare this degradation metabolism with glass flasks fermentation. The methylxanthines were quantified by HPLC analysis. The experiments were realized with the optimized conditions in previous experiments: pH 6.5, 28ºC, inoculation rate 10(6 spores/g substrate, aeration rate 60 mL/min and initial moisture 73%. Under these conditions, after 72 hous of fermentation was achieved only 0.19% of caffeine and 0.014% of theophylline in the coffee husk. The strain proved to be able for caffeine and theophylline degradation by SSF in packed bed column bioreactor.Diversos microrganismos incluindo bactérias, fungos e leveduras são capazes de assimilar a cafeína de meios sintéticos ou de resíduos de café. Existem poucos trabalhos sobre a via de degradação da cafeína em fungos filamentosos, principalmente por fermentação no estado sólido (FES. Estudos de degradação da cafeína por fungos filamentosos em FES usando casca de café como substrato vêm sendo realizados. O objetivo deste trabalho foi investigar a via de degradação da cafeína por Rhizopus delemar em biorreator de colunas aeradas e comparar este metabolismo de degradação com o da fermentação em frascos de vidro. As metilxantinas foram quantificadas por análises em HPLC. Os experimentos foram realizados com as condições otimizadas previamente: pH 6,5, 28ºC, 10(6 espores/g substrato, vazão de ar 60 mL/min e 73% de umidade inicial. Após 90 horas de fermentação, 65% da cafeína foi reduzida, resultando 0

  2. Evaluation of tall rice mutant

    International Nuclear Information System (INIS)

    Hakim, L.; Azam, M.A.; Miah, A.J.; Mansur, M.A.; Akanda, H.R.

    1989-01-01

    One tall mutant (Mut NS1) of rice variety Nizersail was put to multilocation on-farm trial. It showed improvement over the parent in respect of by earlier maturity and higher grain yield at all locations and thus it appears as an improved mutant of Nizersail. (author). 6 refs

  3. Characterization and genetic mapping of a Photoperiod-sensitive dwarf 1 locus in rice (Oryza sativa L.).

    Science.gov (United States)

    Li, Riqing; Xia, Jixing; Xu, Yiwei; Zhao, Xiucai; Liu, Yao-Guang; Chen, Yuanling

    2014-01-01

    Plant height is an important agronomic trait for crop architecture and yield. Most known factors determining plant height function in gibberellin or brassinosteroid biosynthesis or signal transduction. Here, we report a japonica rice (Oryza sativa ssp. japonica) dominant dwarf mutant, Photoperiod-sensitive dwarf 1 (Psd1). The Psd1 mutant showed impaired cell division and elongation, and a severe dwarf phenotype under long-day conditions, but nearly normal growth in short-day. The plant height of Psd1 mutant could not be rescued by gibberellin or brassinosteroid treatment. Genetic analysis with R1 and F2 populations determined that Psd1 phenotype was controlled by a single dominant locus. Linkage analysis with 101 tall F2 plants grown in a long-day season, which were derived from a cross between Psd1 and an indica cultivar, located Psd1 locus on chromosome 1. Further fine-mapping with 1017 tall F2 plants determined this locus on an 11.5-kb region. Sequencing analysis of this region detected a mutation site in a gene encoding a putative lipid transfer protein; the mutation produces a truncated C-terminus of the protein. This study establishes the genetic foundation for understanding the molecular mechanisms regulating plant cell division and elongation mediated by interaction between genetic and environmental factors.

  4. Improved α-amylase production by Aspergillus oryzae after a double deletion of genes involved in carbon catabolite repression.

    Science.gov (United States)

    Ichinose, Sakurako; Tanaka, Mizuki; Shintani, Takahiro; Gomi, Katsuya

    2014-01-01

    In filamentous fungi, the expression of secretory glycoside hydrolase encoding genes, such as those for amylases, cellulases, and xylanases, is generally repressed in the presence of glucose. CreA and CreB have been observed to be regulating factors for carbon catabolite repression. In this study, we generated single and double deletion creA and/or creB mutants in Aspergillus oryzae. The α-amylase activities of each strain were compared under various culture conditions. For the wild-type strain, mRNA levels of α-amylase were markedly decreased in the later stage of submerged culture under inducing conditions, whereas this reduced expression was not observed for single creA and double creA/creB deletion mutants. In addition, α-amylase activity of the wild-type strain was reduced in submerged culture containing high concentrations of inducing sugars, whereas all constructed mutants showed higher α-amylase activities. In particular, the α-amylase activity of the double deletion mutant in a medium containing 5% starch was >10-fold higher than that of the wild-type strain under the same culture conditions. In solid-state cultures using wheat bran as a substrate, the α-amylase activities of single creA and double deletion mutants were >2-fold higher than that of the wild-type strain. These results suggested that deleting both creA and creB resulted in dramatic improvements in the production of secretory glycoside hydrolases in filamentous fungi.

  5. Endophytic Streptomyces spp. as Biocontrol Agents of Rice Bacterial Leaf Blight Pathogen (Xanthomonas oryzae pv. oryzae

    Directory of Open Access Journals (Sweden)

    RATIH DEWI HASTUTI

    2012-12-01

    Full Text Available Xanthomonas oryzae pv. oryzae (Xoo, a causal agent of bacterial leaf blight (BLB, is one of the most important pathogens of rice. The effectiveness of ten Streptomyces spp. isolates in suppressing Xoo disease was assessed in planta and in vitro. In planta experiments were carried out in a greenhouse and arranged in a randomized completely block design (RCBD with three replications. Twenty treatments were tested which included plants inoculated with both Streptomyces spp. and Xoo, and plants inoculated with only Streptomyces spp. Plants inoculated with Xoo and sprayed with a chemical bactericide, and plants inoculated with only Xoo served as positive controls, whereas plants not inoculated with either Streptomyces spp. or Xoo were used as negative controls. The results showed that the effect of endophytic Streptomyces spp. on BLB disease expressed as area under disease progress curve (AUDPC was not significantly different to that on control plants (P > 0.05. However, plants inoculated with endophytic Streptomyces spp. were significantly taller and produced higher tiller number than control plants (P < 0.05. Streptomyces spp. isolate AB131-1 gave the highest plant height. In vitro studies on biocontrol mechanisms of selected Streptomyces spp. isolates showed that isolate LBR02 gave the highest inhibition activity on Xoo growth, followed by AB131-1 and AB131-2. Two isolates (AB131-1 and LBR02 were able to produce chitinase, phosphatase, and siderophore which included biocontrol characteristics. Morphological and colonization studies under SEM and light microscopy confirmed that the three isolates were endophytic Streptomyces spp. from different species. These studies found that the paddy plant which was inoculated with endophytic Streptomyces spp. AB131-1 and infected by Xoo could increase the height of plant and number of tillers.

  6. Variation of photosynthetic tolerance of rice cultivars (Oryza sativa L ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-03-01

    Mar 1, 2010 ... (Oryza sativa L.) to chilling temperature in the light. Xia Li*, Kun Cao, Chao .... 2 mol) formed red-brown trimethine that can be detected quantitatively with spectrophoto- ..... ses through the generation of appropriate signals (H2O2) and the balance ..... was under weak light intensity (Murata, 1989). Light.

  7. Fungicide sensitivity in the wild rice pathogen Bipolaris oryzae

    Science.gov (United States)

    In recent years the occurrence of fungal brown spot, caused by Bipolaris oryzae has increased in cultivated wild rice (Zizania palustris) paddies in spite of the use of fungicides. To implement an efficient integrated disease management system, we are exploring whether field isolates have developed ...

  8. Bipolaris oryzae, a novel fungal opportunist causing keratitis

    NARCIS (Netherlands)

    Al-Hatmi, Abdullah

    2015-01-01

    We report a case of mycotic keratitis caused by Bipolaris oryzae with predisposing trauma from a foreign body. The fungus was identified by sequencing the internal transcribed spacer (ITS) region, translation elongation factor 1α (TEF1) gene and partial glyceraldehyde-3-phosphate dehydrogenase

  9. Antagonism of rice phylloplane fungi against Cercospora oryzae

    Science.gov (United States)

    Mardani, A.; Hadiwiyono

    2018-03-01

    Narrow brown leaf spot (NBLS) caused by Cercospora oryzae Miyake is one of the important obstacle in rice cultivation that can decrease the productivity up to 40%. It has been known well that some phylloplane fungi are antagonistic to some leaf diseases. Phylloplane fungi of rice however haven’t been studied much and poorly understood as biological control agent of rice pathogen such C. oryzae. The research aimed to study the antagonism of some phylloplane fungi of rice against C. oryzae. At least 14 isolates of phylloplane fungi were collected which consisted of six pathogenic and eight nonpathogenic variants. All of nonpathogenic isolates were antagonistic against C. oryzae both in vitro and only one isolate could not inhibit the infection of the pathogen in vivo. Some isolates were identified as Aspergillus, Mucor, Penicillium, Fusarium, and Trichoderma. The isolate of Mucor and Fusarium could inhibit the highest growth of pathogen on potato dextrose medium that were at 36.0% and 35.5% respectively. Whereas on artificial inoculation on rice, some isolates such Penicillium and Fusarium could inhibit most effectively and were significantly different to Mencozeb application with dosage 5g L-1.

  10. Rice diversity panels available through the genetic stocks oryza collection

    Science.gov (United States)

    The Genetic Stocks Oryza (GSOR) Collection was established in 2004 at the USDA-ARS, Dale Bumpers National Rice Research Center (DBNRRC) located in Stuttgart, AR. The mission of GSOR is to provide unique genetic resources to the rice research community for genetic and genomics related research. GSOR ...

  11. High Levels of Phytophenolics and Antioxidant Activities in Oryza ...

    African Journals Online (AJOL)

    Purpose: To investigate phenolic levels, phytophenolic profiles and total antioxidant activities of Oryza sativa, unpolished Thai rice. Methods: Unpolished Thai rice strains of Leum Phua, Klam, Hawm Nil and Black Rose were measured for antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH), ...

  12. The Population Structure of African Cultivated Rice Oryza glaberrima (Steud.)

    DEFF Research Database (Denmark)

    Semon, Mande; Nielsen, Rasmus; Jones, Monty P.

    2005-01-01

    Genome-wide linkage disequilibrium (LD) was investigated for 198 accessions of Oryza glaberrima using 93 nuclear microsatellite markers. Significantly elevated levels of LD were detected, even among distantly located markers. Free recombination among loci at the population genetic level was shown...

  13. Cyclopiazonic Acid Biosynthesis of Aspergillus flavus and Aspergillus oryzae

    Science.gov (United States)

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

  14. Characteristics of immobilized aminoacylase from Aspergillus oryzae on macroporous copolymers.

    Science.gov (United States)

    He, B L; Jiang, P; Qiu, Y B

    1990-01-01

    Aminoacylase from Aspergillus oryzae was adsorbed on functionallized macroporous copolymers where the enzyme showed excellent catalyzing activity and operation stability. Various factors which effect the activity of the immobilized aminoacylase such as temperature, pH and ionic strength were investigated. The continuous operation of the enzyme immobilized on macroporous copolymers was compared with that of the enzyme immobilized on DEAE-Sephadex.

  15. Peroxisomal alanine: glyoxylate aminotransferase AGT1 is indispensable for appressorium function of the rice blast pathogen, Magnaporthe oryzae.

    Directory of Open Access Journals (Sweden)

    Vijai Bhadauria

    Full Text Available The role of β-oxidation and the glyoxylate cycle in fungal pathogenesis is well documented. However, an ambiguity still remains over their interaction in peroxisomes to facilitate fungal pathogenicity and virulence. In this report, we characterize a gene encoding an alanine, glyoxylate aminotransferase 1 (AGT1 in Magnaporthe oryzae, the causative agent of rice blast disease, and demonstrate that AGT1 is required for pathogenicity of M. oryzae. Targeted deletion of AGT1 resulted in the failure of penetration via appressoria; therefore, mutants lacking the gene were unable to induce blast symptoms on the hosts rice and barley. This penetration failure may be associated with a disruption in lipid mobilization during conidial germination as turgor generation in the appressorium requires mobilization of lipid reserves from the conidium. Analysis of enhanced green fluorescent protein expression using the transcriptional and translational fusion with the AGT1 promoter and open reading frame, respectively, revealed that AGT1 expressed constitutively in all in vitro grown cell types and during in planta colonization, and localized in peroxisomes. Peroxisomal localization was further confirmed by colocalization with red fluorescent protein fused with the peroxisomal targeting signal 1. Surprisingly, conidia produced by the Δagt1 mutant were unable to form appressoria on artificial inductive surfaces, even after prolonged incubation. When supplemented with nicotinamide adenine dinucleotide (NAD(++pyruvate, appressorium formation was restored on an artificial inductive surface. Taken together, our data indicate that AGT1-dependent pyruvate formation by transferring an amino group of alanine to glyoxylate, an intermediate of the glyoxylate cycle is required for lipid mobilization and utilization. This pyruvate can be converted to non-fermentable carbon sources, which may require reoxidation of NADH generated by the β-oxidation of fatty acids to NAD(+ in

  16. Cloning, Expression and Characterization of a Novel Fructosyltransferase from Aspergillus oryzae ZZ-01 for the Synthesis of Sucrose 6-Acetate

    Directory of Open Access Journals (Sweden)

    Tao Wei

    2016-05-01

    Full Text Available A 1521 bp gene encoding for a novel fructosyltransferase from Aspergillus oryzae ZZ-01 (AoFT has been amplified by RACE and TAIL PCR, and functionally overexpressed in Escherichia coli BL 21-CodonPlus (DE3-RIL. The recombinant A. oryzae ZZ-01 fructosyltransferases (r-AoFT was purified to homogeneity after Ni-NTA affinity and Superdex-200 gel filtration chromatography. SDS-PAGE analysis of the purified r-AoFT revealed a single protein band with an apparent molecular mass of 60.0 kDa. The r-AoFT enzyme exhibited its optimal activity at 55 °C and pH 5.5, and maintained about 63% of its activity even after 60 min of treatment at 60 °C. The addition of Mg2+ led to an increase in the activity of r-AoFT, whereas Zn2+, Cu2+ and Ni2+ led to a reduction in its activity. Six site-directed mutants of r-AoFT (D39A, D164A, E216A, N38L, S99A and Y282A were constructed and characterized biochemically. The N38L, S99A and Y282A mutants had lower Km and higher Vmax values than the wild-type enzyme, highlighting their higher binding affinity for the substrates. These results therefore suggest that r-AoFT could be used for the enzymatic synthesis of Suc6A from sucrose and glucose 6-acetate.

  17. Could abiotic stress tolerance in wild relatives of rice be used to improve Oryza sativa?

    Science.gov (United States)

    Atwell, Brian J; Wang, Han; Scafaro, Andrew P

    2014-02-01

    Oryza sativa and Oryza glaberrima have been selected to acquire and partition resources efficiently as part of the process of domestication. However, genetic diversity in cultivated rice is limited compared to wild Oryza species, in spite of 120,000 genotypes being held in gene banks. By contrast, there is untapped diversity in the more than 20 wild species of Oryza, some having been collected from just a few coastal locations (e.g. Oryza schlechteri), while others are widely distributed (e.g. Oryza nivara and Oryza rufipogon). The extent of DNA sequence diversity and phenotypic variation is still being established in wild Oryza, with genetic barriers suggesting a vast range of morphologies and function even within species, such as has been demonstrated for Oryza meridionalis. With increasing climate variability and attempts to make more marginal land arable, abiotic and biotic stresses will be managed over the coming decades by tapping into the genetic diversity of wild relatives of O. sativa. To help create a more targeted approach to sourcing wild rice germplasm for abiotic stress tolerance, we have created a climate distribution map by plotting the natural occurrence of all Oryza species against corresponding temperature and moisture data. We then discuss interspecific variation in phenotype and its significance for rice, followed by a discussion of ways to integrate germplasm from wild relatives into domesticated rice. Crown Copyright © 2013. Published by Elsevier Ireland Ltd. All rights reserved.

  18. Interaction between Pyricularia oryzae, four Helminthosporium species and Curvularia lunata in rice leaves

    Directory of Open Access Journals (Sweden)

    M. Bahous

    2003-08-01

    Full Text Available The interaction between six fungal parasites of rice: Pyricularia oryzae, Helminthosporium oryzae, H. sativum, H. spiciferum, H. australiensis and Curvularia lunata was studied quantitatively by a modified plant ecology technique known as the de Wit replacement series. Each fungus was inoculated alone or in combination with one of the other five fungi in various proportions into rice plants under experimental conditions. Leaves developing lesions were harvested and incubated in a moist chamber. The yield of each fungus was its conidial production on the rice leaves. The artificial inoculations indicated that interactions between the pathogens in the mixture could be beneficial, antagonistic, or null. Interspecific interaction (i.e. antagonism occurred in the majority of paired combinations (H. oryzae + P. oryzae; H. sativum + H. spiciferum, H. australiensis, C. lunata or P. oryzae; H. australiensis + H. spiciferum, C. lunata or P. oryzae; and P. oryzae + C. lunata. The relative yield total (RYT lines were significantly lower than the expected value, which is 1. The RYT lines were concave upward, revealing a beneficial effect of one or both pathogens on the other, when H. oryzae was in mixture with H. sativum or H. spiciferum. A null effect between fungi occurred in four combinations (H. oryzae + H. australiensis or C. lunata; H. spiciferum + C. lunata; and P. oryzae + H. spiciferum showing that with these combinations inter- and intraspecific competitions were equal in intensity. Thus, the de Wit replacement series technique indicated that it was possible to quantify the interaction between all the pathogenic fungi tested.

  19. Transposable element distribution, abundance and role in genome size variation in the genus Oryza.

    Science.gov (United States)

    Zuccolo, Andrea; Sebastian, Aswathy; Talag, Jayson; Yu, Yeisoo; Kim, HyeRan; Collura, Kristi; Kudrna, Dave; Wing, Rod A

    2007-08-29

    The genus Oryza is composed of 10 distinct genome types, 6 diploid and 4 polyploid, and includes the world's most important food crop - rice (Oryza sativa [AA]). Genome size variation in the Oryza is more than 3-fold and ranges from 357 Mbp in Oryza glaberrima [AA] to 1283 Mbp in the polyploid Oryza ridleyi [HHJJ]. Because repetitive elements are known to play a significant role in genome size variation, we constructed random sheared small insert genomic libraries from 12 representative Oryza species and conducted a comprehensive study of the repetitive element composition, distribution and phylogeny in this genus. Particular attention was paid to the role played by the most important classes of transposable elements (Long Terminal Repeats Retrotransposons, Long interspersed Nuclear Elements, helitrons, DNA transposable elements) in shaping these genomes and in their contributing to genome size variation. We identified the elements primarily responsible for the most strikingly genome size variation in Oryza. We demonstrated how Long Terminal Repeat retrotransposons belonging to the same families have proliferated to very different extents in various species. We also showed that the pool of Long Terminal Repeat Retrotransposons is substantially conserved and ubiquitous throughout the Oryza and so its origin is ancient and its existence predates the speciation events that originated the genus. Finally we described the peculiar behavior of repeats in the species Oryza coarctata [HHKK] whose placement in the Oryza genus is controversial. Long Terminal Repeat retrotransposons are the major component of the Oryza genomes analyzed and, along with polyploidization, are the most important contributors to the genome size variation across the Oryza genus. Two families of Ty3-gypsy elements (RIRE2 and Atlantys) account for a significant portion of the genome size variations present in the Oryza genus.

  20. Isolation and characterisation of a dwarf rice mutant exhibiting defective gibberellins biosynthesis.

    Science.gov (United States)

    Ji, S H; Gururani, M A; Lee, J W; Ahn, B-O; Chun, S-C

    2014-03-01

    We have isolated a severe dwarf mutant derived from a Ds (Dissociation) insertion mutant rice (Oryza sativa var. japonica c.v. Dongjin). This severe dwarf phenotype, has short and dark green leaves, reduced shoot growth early in the seedling stage, and later severe dwarfism with failure to initiate flowering. When treated with bioactive GA3 , mutants are restored to the normal wild-type phenotype. Reverse transcription PCR analyses of 22 candidate genes related to the gibberellin (GA) biosynthesis pathway revealed that among 22 candidate genes tested, a dwarf mutant transcript was not expressed only in one OsKS2 gene. Genetic analysis revealed that the severe dwarf phenotype was controlled by recessive mutation of a single nuclear gene. The putative OsKS2 gene was a chromosome 4-located ent-kaurene synthase (KS), encoding the enzyme that catalyses an early step of the GA biosynthesis pathway. Sequence analysis revealed that osks2 carried a 1-bp deletion in the ORF region of OsKS2, which led to a loss-of-function mutation. The expression pattern of OsKS2 in wild-type cv Dongjin, showed that it is expressed in all organs, most prominently in the stem and floral organs. Morphological characteristics of the dwarf mutant showed dramatic modifications in internal structure and external morphology. We propose that dwarfism in this mutant is caused by a point mutation in OsKS2, which plays a significant role in growth and development of higher plants. Further investigation on OsKS2 and other OsKS-like proteins is underway and may yield better understanding of the putative role of OsKS in severe dwarf mutants. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

  1. The C2H2-type transcription factor, FlbC, is involved in the transcriptional regulation of Aspergillus oryzae glucoamylase and protease genes specifically expressed in solid-state culture.

    Science.gov (United States)

    Tanaka, Mizuki; Yoshimura, Midori; Ogawa, Masahiro; Koyama, Yasuji; Shintani, Takahiro; Gomi, Katsuya

    2016-07-01

    Aspergillus oryzae produces a large amount of secreted proteins in solid-state culture, and some proteins such as glucoamylase (GlaB) and acid protease (PepA) are specifically produced in solid-state culture, but rarely in submerged culture. From the disruption mutant library of A. oryzae transcriptional regulators, we successfully identified a disruption mutant showing an extremely low production level of GlaB but a normal level of α-amylase production. This strain was a disruption mutant of the C2H2-type transcription factor, FlbC, which is reported to be involved in the regulation of conidiospore development. Disruption mutants of other upstream regulators comprising a conidiation regulatory network had no apparent effect on GlaB production in solid-state culture. In addition to GlaB, the production of acid protease in solid-state culture was also markedly decreased by flbC disruption. Northern blot analyses revealed that transcripts of glaB and pepA were significantly decreased in the flbC disruption strain. These results suggested that FlbC is involved in the transcriptional regulation of genes specifically expressed under solid-state cultivation conditions, possibly independent of the conidiation regulatory network.

  2. MoDUO1, a Duo1-like gene, is required for full virulence of the rice blast fungus Magnaporthe oryzae.

    Science.gov (United States)

    Peng, Haowen; Feng, Youjun; Zhu, Xiaohui; Lan, Xiuwan; Tang, Mei; Wang, Jinzi; Dong, Haitao; Chen, Baoshan

    2011-12-01

    Duo1, a major component of the Dam1 complex which has been found in two species of yeast (the budding yeast Saccharomyces cerevisae and the fission yeast Schizosaccharomyces pombe), is involved in mitosis-related chromosome segregation, while its relevance to pathogenicity in filamentous fungi remains unclear. This report elucidated this very fact in the case of the rice blast fungus Magnaporthe oryzae. A gene designated MoDUO1 that encodes a Duo1-like homolog (MoDuo1) was discovered in the M. oryzae genome. Two types of MoDUO1 mutants were obtained using genetic approaches of Agrobacterium-mediated gene disruption and homologous recombination. Both disruption and deletion of MoDUO1 can exert profound effects on the formation pattern of conidiophores and conidial morphology, such as abnormal nucleic numbers in conidia and delayed extension of infectious hyphae. Intriguingly, plant infection assays demonstrated that inactivation of MoDUO1 significantly attenuates the virulence in its natural host rice leaves, and functional complementation can restore it. Subcellular localization assays showed that MoDuo1 is mainly distributed in the cytosol of fungal cells. Proteomics-based investigation revealed that the expression of four mitosis-related proteins is shut down in the MoDUO1 mutant, suggesting that MoDuo1 may have a function in mitosis. In light of the fact that Duo1 orthologs are widespread in plant and human fungal pathogens, our finding may represent a common mechanism underlying fungal virulence. To the best of our knowledge, this is the first example of linking a Duo1-like homolog to the pathogenesis of a pathogenic fungus, which might provide clues to additional studies on the role of Dam1 complex in M. oryzae and its interaction with rice.

  3. The Swedish mutant barley collection

    International Nuclear Information System (INIS)

    1989-01-01

    Full text: The Swedish mutation research programme in barley began about 50 years ago and has mainly been carried out at Svaloev in co-operation with the institute of Genetics at the University of Lund. The collection has been produced from different Swedish high-yielding spring barley varieties, using the following mutagens: X-rays, neutrons, several organic chemical compounds such as ethyleneimine, several sulfonate derivatives and the inorganic chemical mutagen sodium azide. Nearly 10,000 barley mutants are stored in the Nordic Gene Bank and documented in databases developed by Udda Lundquist, Svaloev AB. The collection consists of the following nine categories with 94 different types of mutants: 1. Mutants with changes in the spike and spikelets; 2. Changes in culm length and culm composition; 3. Changes in growth types; 4. Physiological mutants; 5. Changes in awns; 6. Changes in seed size and shape; 7. Changes in leaf blades; 8. Changes in anthocyanin and colour; 9. Resistance to barley powdery mildew. Barley is one of the most thoroughly investigated crops in terms of induction of mutations and mutation genetics. So far, about half of the mutants stored at the Nordic Gene Bank, have been analysed genetically; They constitute, however, only a minority of the 94 different mutant types. The genetic analyses have given valuable insights into the mutation process but also into the genetic architecture of various characters. A number of mutants of two-row barley have been registered and commercially released. One of the earliest released, Mari, an early maturing, daylength neutral, straw stiff mutant, is still grown in Iceland. The Swedish mutation material has been used in Sweden, but also in other countries, such as Denmark, Germany, and USA, for various studies providing a better understanding of the barley genome. The collection will be immensely valuable for future molecular genetical analyses of clone mutant genes. (author)

  4. The Swedish mutant barley collection

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1989-07-01

    Full text: The Swedish mutation research programme in barley began about 50 years ago and has mainly been carried out at Svaloev in co-operation with the institute of Genetics at the University of Lund. The collection has been produced from different Swedish high-yielding spring barley varieties, using the following mutagens: X-rays, neutrons, several organic chemical compounds such as ethyleneimine, several sulfonate derivatives and the inorganic chemical mutagen sodium azide. Nearly 10,000 barley mutants are stored in the Nordic Gene Bank and documented in databases developed by Udda Lundquist, Svaloev AB. The collection consists of the following nine categories with 94 different types of mutants: 1. Mutants with changes in the spike and spikelets; 2. Changes in culm length and culm composition; 3. Changes in growth types; 4. Physiological mutants; 5. Changes in awns; 6. Changes in seed size and shape; 7. Changes in leaf blades; 8. Changes in anthocyanin and colour; 9. Resistance to barley powdery mildew. Barley is one of the most thoroughly investigated crops in terms of induction of mutations and mutation genetics. So far, about half of the mutants stored at the Nordic Gene Bank, have been analysed genetically; They constitute, however, only a minority of the 94 different mutant types. The genetic analyses have given valuable insights into the mutation process but also into the genetic architecture of various characters. A number of mutants of two-row barley have been registered and commercially released. One of the earliest released, Mari, an early maturing, daylength neutral, straw stiff mutant, is still grown in Iceland. The Swedish mutation material has been used in Sweden, but also in other countries, such as Denmark, Germany, and USA, for various studies providing a better understanding of the barley genome. The collection will be immensely valuable for future molecular genetical analyses of clone mutant genes. (author)

  5. Antioxidant activity of raw, cooked and Rhizopus oligosporus fermented beans of Canavalia of coastal sand dunes of Southwest India.

    Science.gov (United States)

    Niveditha, Vedavyas R; Sridhar, Kandikere R

    2014-11-01

    The raw and processed (cooked and cooked + solid-state fermented with Rhizopus oligosporus) split beans of two landraces of coastal sand dune wild legumes (Canavalia cathartica and Canavalia maritima) of the southwest coast of India were examined for bioactive compounds (total phenolics, tannins and vitamin C) and antioxidant potential (total antioxidant activity, ferrous-ion chelating capacity, DPPH free radical-scavenging activity and reducing activity). One-way ANOVA revealed significant elevation of bioactive compounds as well as antioxidant activities in fermented beans compared to raw and cooked beans in both legumes (p beans of both legumes were significantly lowest compared to raw and cooked beans (p beans of C. cathartica, while total antioxidant and free radical-scavenging activities of fermented beans of C. maritima were clustered. The present study demonstrated that split beans of coastal sand dune Canavalia fermented by R. oligosporus endowed with high bioactive principles as well as antioxidant potential and thus serve as future nutraceutical source.

  6. Lead Biosorption by Self-Immobilized Rhizopus nigricans Pellets in a Laboratory Scale Packed Bed Column: Mathematical Model and Experiment

    Directory of Open Access Journals (Sweden)

    Adela Kogej

    2010-01-01

    Full Text Available The biosorption of lead ions from aqueous solution on a self-immobilized Rhizopus nigricans biomass has been studied. Experiments were performed in a laboratory scale packed bed column at different liquid flow rates and biosorbent bed heights. Recorded experimental breakthrough curves were compared to those predicted by a mathematical model, which was developed to simulate a packed bed biosorption process by a soft, self-immobilized fungal biosorbent. In the range of examined experimental conditions, the biomass characteristics such as pellet porosity and biosorption capacity substantially affected the predicted response curve. General correlations for the estimation of the intra-pellet effective diffusivity, the external mass transfer coefficient, as well as axial dispersion were successfully applied in this biological system with specific mechanical properties. Under the experimental conditions, mass transfer is controlled by the external film resistance, while the intra-pellet mass transfer resistance, as well as the effect of axial dispersion, can be neglected. A new parameter α, the fraction of active biomass, with an average value of α=0.7, was introduced to take into account the specific biomass characteristics, and consequently the observed non-ideal liquid flow through the bed of fungal pellets.

  7. Water-deficit tolerant classification in mutant lines of indica rice

    Directory of Open Access Journals (Sweden)

    Suriyan Cha-um

    2012-04-01

    Full Text Available Water shortage is a major abiotic stress for crop production worldwide, limiting the productivity of crop species, especially in dry-land agricultural areas. This investigation aimed to classify the water-deficit tolerance in mutant rice (Oryza sativa L. spp. indica genotypes during the reproductive stage. Proline content in the flag leaf of mutant lines increased when plants were subjected to water deficit. Relative water content (RWC in the flag leaf of different mutant lines dropped in relation to water deficit stress. A decrease RWC was positively related to chlorophyll a degradation. Chlorophyll a , chlorophyll b , total chlorophyll , total carotenoids , maximum quantum yield of PSII , stomatal conductance , transpiration rate and water use efficiency in mutant lines grown under water deficit conditions declined in comparison to the well-watered, leading to a reduction in net-photosynthetic rate. In addition, when exposed to water deficit, panicle traits, including panicle length and fertile grains were dropped. The biochemical and physiological data were subjected to classify the water deficit tolerance. NSG19 (positive control and DD14 were identified as water deficit tolerant, and AA11, AA12, AA16, BB13, BB16, CC12, CC15, EE12, FF15, FF17, G11 and IR20 (negative control as water deficit sensitive, using Ward's method.

  8. Kinetics of improved 1,4-alpha-D-glucan glucohydrolase biosynthesis from a newly isolated Aspergillus oryzae IIB-6 and parameter significance analysis by 2-factorial design.

    Science.gov (United States)

    Fatima, Bilqees; Ali, Sikander

    2012-01-01

    Sixteen different mould cultures viz. Aspergillus, Alternaria, Arthroderma, Trichoderma, Fusarium, Penicillium, Rhizopus and Chochliobolus were isolated from the soil samples of Qatar by serial dilution method. The preliminary screening of isolates was done by selecting initial colonies showing relatively bigger zones of starch hydrolysis on nutrient agar plates. The isolates were then subjected to secondary screening by submerged fermentation (SmF). The 1,4-α-D-glucan glucohydrolase (GGH) activity ranged from 1.906-12.675 U/ml/min. The product yield was analysed in dependence of mycelial morphology, biomass level and protein content. The isolate Aspergillus oryzae llB-6 which gave maximum enzyme production was incubated in M3 medium containing 20 g/l starch, 10 g/l lactose, 8.5 g/l yeast extract, 6 g/l corn steep liquor (CSL), 1.2 g/l MgSO4.7H2O, 1.3 g/l NH4Cl, 0.6 g/l CaCl2.2H2O, pH 5 at 30±2°C and 200 rpm. On the basis of kinetic variables, notably Qp (0.058±0.01(a) U/g/h), Yp/s (0.308±0.03(ab) U/g) and qp (0.210±0.032(abc) U/g fungal biomass/h), A. oryzae IIB-6 was found to be a hyper producer of GGH (LSD 0.0345) compared to A. kawachii IIB-2. A noticeable enhancement in enzyme activity of over 30% was observed (13.917±1.01 U/ml/min) when the process parameters viz. cultural conditions (pH 5, incubation period 72 h) and nutritional requirements (6 g/l CSL, 9.5 g/l yeast extract, 10 g/l starch, 20 g/l lactose) were further optimized using a 2-factorial Plackett-Burman design. The model terms were found to be highly significant (HS, p≤0.05), indicating the potential utility of the culture (dof~3).

  9. Biochemical and structural properties of cyanases from Arabidopsis thaliana and Oryza sativa.

    Directory of Open Access Journals (Sweden)

    Dan Qian

    Full Text Available Cyanate is toxic to all organisms. Cyanase converts cyanate to CO₂ and NH₃ in a bicarbonate-dependent reaction. The biophysical functions and biochemical characteristics of plant cyanases are poorly studied, although it has been investigated in a variety of proteobacteria, cyanobacteria and fungi. In this study, we characterised plant cyanases from Arabidopsis thaliana and Oryza sativa (AtCYN and OsCYN. Prokaryotic-expressed AtCYN and OsCYN both showed cyanase activity in vitro. Temperature had a similar influence on the activity of both cyanases, but pH had a differential impact on AtCYN and OsCYN activity. Homology modelling provided models of monomers of AtCYN and OsCYN, and a coimmunoprecipitation assay and gel filtration indicated that AtCYN and OsCYN formed homodecamers. The analysis of single-residue mutants of AtCYN indicated that the conserved catalytic residues also contributed to the stability of the homodecamer. KCNO treatment inhibited Arabidopsis germination and early seedling growth. Plants containing AtCYN or OsCYN exhibited resistance to KCNO stress, which demonstrated that one role of cyanases in plants is detoxification. Transcription level of AtCYN was higher in the flower than in other organs of Arabidopsis. AtCYN transcription was not significantly affected by KCNO treatment in Arabidopsis, but was induced by salt stress. This research broadens our knowledge on plant detoxification of cyanate via cyanase.

  10. Curated genome annotation of Oryza sativa ssp. japonica and comparative genome analysis with Arabidopsis thaliana

    Science.gov (United States)

    Itoh, Takeshi; Tanaka, Tsuyoshi; Barrero, Roberto A.; Yamasaki, Chisato; Fujii, Yasuyuki; Hilton, Phillip B.; Antonio, Baltazar A.; Aono, Hideo; Apweiler, Rolf; Bruskiewich, Richard; Bureau, Thomas; Burr, Frances; Costa de Oliveira, Antonio; Fuks, Galina; Habara, Takuya; Haberer, Georg; Han, Bin; Harada, Erimi; Hiraki, Aiko T.; Hirochika, Hirohiko; Hoen, Douglas; Hokari, Hiroki; Hosokawa, Satomi; Hsing, Yue; Ikawa, Hiroshi; Ikeo, Kazuho; Imanishi, Tadashi; Ito, Yukiyo; Jaiswal, Pankaj; Kanno, Masako; Kawahara, Yoshihiro; Kawamura, Toshiyuki; Kawashima, Hiroaki; Khurana, Jitendra P.; Kikuchi, Shoshi; Komatsu, Setsuko; Koyanagi, Kanako O.; Kubooka, Hiromi; Lieberherr, Damien; Lin, Yao-Cheng; Lonsdale, David; Matsumoto, Takashi; Matsuya, Akihiro; McCombie, W. Richard; Messing, Joachim; Miyao, Akio; Mulder, Nicola; Nagamura, Yoshiaki; Nam, Jongmin; Namiki, Nobukazu; Numa, Hisataka; Nurimoto, Shin; O’Donovan, Claire; Ohyanagi, Hajime; Okido, Toshihisa; OOta, Satoshi; Osato, Naoki; Palmer, Lance E.; Quetier, Francis; Raghuvanshi, Saurabh; Saichi, Naomi; Sakai, Hiroaki; Sakai, Yasumichi; Sakata, Katsumi; Sakurai, Tetsuya; Sato, Fumihiko; Sato, Yoshiharu; Schoof, Heiko; Seki, Motoaki; Shibata, Michie; Shimizu, Yuji; Shinozaki, Kazuo; Shinso, Yuji; Singh, Nagendra K.; Smith-White, Brian; Takeda, Jun-ichi; Tanino, Motohiko; Tatusova, Tatiana; Thongjuea, Supat; Todokoro, Fusano; Tsugane, Mika; Tyagi, Akhilesh K.; Vanavichit, Apichart; Wang, Aihui; Wing, Rod A.; Yamaguchi, Kaori; Yamamoto, Mayu; Yamamoto, Naoyuki; Yu, Yeisoo; Zhang, Hao; Zhao, Qiang; Higo, Kenichi; Burr, Benjamin; Gojobori, Takashi; Sasaki, Takuji

    2007-01-01

    We present here the annotation of the complete genome of rice Oryza sativa L. ssp. japonica cultivar Nipponbare. All functional annotations for proteins and non-protein-coding RNA (npRNA) candidates were manually curated. Functions were identified or inferred in 19,969 (70%) of the proteins, and 131 possible npRNAs (including 58 antisense transcripts) were found. Almost 5000 annotated protein-coding genes were found to be disrupted in insertional mutant lines, which will accelerate future experimental validation of the annotations. The rice loci were determined by using cDNA sequences obtained from rice and other representative cereals. Our conservative estimate based on these loci and an extrapolation suggested that the gene number of rice is ∼32,000, which is smaller than previous estimates. We conducted comparative analyses between rice and Arabidopsis thaliana and found that both genomes possessed several lineage-specific genes, which might account for the observed differences between these species, while they had similar sets of predicted functional domains among the protein sequences. A system to control translational efficiency seems to be conserved across large evolutionary distances. Moreover, the evolutionary process of protein-coding genes was examined. Our results suggest that natural selection may have played a role for duplicated genes in both species, so that duplication was suppressed or favored in a manner that depended on the function of a gene. PMID:17210932

  11. Mutants of alfalfa mosaic virus

    International Nuclear Information System (INIS)

    Roosien, J.

    1983-01-01

    In this thesis the isolation and characterization of a number of mutants of alfalfa mosaic virus, a plant virus with a coat protein dependent genome, is described. Thermo-sensitive (ts) mutants were selected since, at least theoretically, ts mutations can be present in all virus coded functions. It was found that a high percentage of spontaneous mutants, isolated because of their aberrant symptoms, were ts. The majority of these isolates could grow at the non-permissive temperature in the presence of a single wild type (wt) component. To increase the mutation rate virus preparations were treated with several mutagens. After nitrous acid treatment or irradiation with ultraviolet light, an increase in the level of mutations was observed. UV irradiation was preferred since it did not require large amounts of purified viral components. During the preliminary characterization of potential ts mutants the author also obtained one structural and several symptom mutants which were analysed further (chapter 7, 8 and 9). The properties of the ts mutants are described in chapter 3-7. (Auth.)

  12. Root hair mutants of barley

    International Nuclear Information System (INIS)

    Engvild, K.C.; Rasmussen, K.

    2005-01-01

    Barley mutants without root hairs or with short or reduced root hairs were isolated among M 2 seeds of 'Lux' barley (Hordeum vulgare L.) after acidified sodium azide mutagenesis. Root hair mutants are investigated intensively in Arabidopsis where about 40 genes are known. A few root hair mutants are known in maize, rice, barley and tomato. Many plants without root hairs grow quite well with good plant nutrition, and mutants have been used for investigations of uptake of strongly bound nutrients like phosphorus, iron, zinc and silicon. Seed of 'Lux' barley (Sejet Plant Breeding, Denmark) were soaked overnight, and then treated with 1.5-millimolarsodium azide in 0.1 molar sodium phosphate buffer, pH 3, for 2.5 hours according to the IAEA Manual on Mutation Breeding (2nd Ed.). After rinsing in tap water and air-drying, the M 2 seeds were sown in the field the same day. Spikes, 4-6 per M 1 plant, were harvested. The mutation frequency was similar to that obtained with other barley cultivars from which low-phytate mutants were isolated [5]. Seeds were germinated on black filter paper in tap water for 3 or 4 days before scoring for root hair mutants

  13. Utilization of Aspergillus oryzae to produce pectin lyase from various agro-industrial residues

    OpenAIRE

    Koser, Safia; Anwar, Zahid; Iqbal, Zafar; Anjum, Awais; Aqil, Tahir; Mehmood, Sajid; Irshad, Muhammad

    2014-01-01

    The present study was aimed to investigate the culture influence on pectin lyase production potential of fungal strain Aspergillus oryzae. The enzyme profile of A. oryzae showed highest activity of pectin lyase after 3rd day of incubation on lemon peel waste under solid state fermentation conditions. To induce the pectin lyase synthesis capability of A. oryzae at optimal level various culture variables including physical and nutritional parameters were optimized by adopting classical optimiza...

  14. Survey of the transcriptome of Aspergillus oryzae via massively parallel mRNA sequencing

    OpenAIRE

    Wang, Bin; Guo, Guangwu; Wang, Chao; Lin, Ying; Wang, Xiaoning; Zhao, Mouming; Guo, Yong; He, Minghui; Zhang, Yong; Pan, Li

    2010-01-01

    Aspergillus oryzae, an important filamentous fungus used in food fermentation and the enzyme industry, has been shown through genome sequencing and various other tools to have prominent features in its genomic composition. However, the functional complexity of the A. oryzae transcriptome has not yet been fully elucidated. Here, we applied direct high-throughput paired-end RNA-sequencing (RNA-Seq) to the transcriptome of A. oryzae under four different culture conditions. With the high resoluti...

  15. Gene Ontology annotation of the rice blast fungus, Magnaporthe oryzae

    Directory of Open Access Journals (Sweden)

    Deng Jixin

    2009-02-01

    Full Text Available Abstract Background Magnaporthe oryzae, the causal agent of blast disease of rice, is the most destructive disease of rice worldwide. The genome of this fungal pathogen has been sequenced and an automated annotation has recently been updated to Version 6 http://www.broad.mit.edu/annotation/genome/magnaporthe_grisea/MultiDownloads.html. However, a comprehensive manual curation remains to be performed. Gene Ontology (GO annotation is a valuable means of assigning functional information using standardized vocabulary. We report an overview of the GO annotation for Version 5 of M. oryzae genome assembly. Methods A similarity-based (i.e., computational GO annotation with manual review was conducted, which was then integrated with a literature-based GO annotation with computational assistance. For similarity-based GO annotation a stringent reciprocal best hits method was used to identify similarity between predicted proteins of M. oryzae and GO proteins from multiple organisms with published associations to GO terms. Significant alignment pairs were manually reviewed. Functional assignments were further cross-validated with manually reviewed data, conserved domains, or data determined by wet lab experiments. Additionally, biological appropriateness of the functional assignments was manually checked. Results In total, 6,286 proteins received GO term assignment via the homology-based annotation, including 2,870 hypothetical proteins. Literature-based experimental evidence, such as microarray, MPSS, T-DNA insertion mutation, or gene knockout mutation, resulted in 2,810 proteins being annotated with GO terms. Of these, 1,673 proteins were annotated with new terms developed for Plant-Associated Microbe Gene Ontology (PAMGO. In addition, 67 experiment-determined secreted proteins were annotated with PAMGO terms. Integration of the two data sets resulted in 7,412 proteins (57% being annotated with 1,957 distinct and specific GO terms. Unannotated proteins

  16. Mutants induced in winter rye (Secale cereale L.): Short straw-mutant No. 2714 and late-senescence mutant

    Energy Technology Data Exchange (ETDEWEB)

    Muszynski, S; Darlewska, M [Department of Plant Breeding and Seed Science, Warsaw Agricultural University, Warsaw (Poland)

    1990-01-01

    Full text: Mutants were induced by treating dormant seeds with ionizing radiation (fast neutrons) or chemicals (N-nitroso-N-ethyl urea or sodium azide). Among several mutants obtained, of special value is the short-straw mutant No. 2714 and a late senescent mutant. (author)

  17. Aspergillus oryzae nrtA affects kojic acid production.

    Science.gov (United States)

    Sano, Motoaki

    2016-09-01

    We analyzed the role of the nitrate transporter-encoding gene (nrtA) of Aspergillus oryzae by gene disruption. Southern hybridization analysis indicated that homologous recombination occurred at the resident nrtA locus. Real-time PCR showed that the nrtA gene was strongly inducible by NaNO3. The nrtA disruptant did not exhibit normal growth when nitrate was available as the sole nitrogen source. These results indicate that NrtA is essential for nitrate uptake in A. oryzae. Kojic acid (KA) production was inhibited by the addition of a small amount of sodium nitrate. The nrtA-disrupted strain was deficient in the uptake of nitrate. As a result, KA production in this strain was not considerably affected by the presence of nitrate.

  18. Immobilization of Isolated Lipase From Moldy Copra (Aspergillus Oryzae

    Directory of Open Access Journals (Sweden)

    Seniwati Dali

    2011-01-01

    Full Text Available Enzyme immobilization is a recovery technique that has been studied in several years, using support as a media to help enzyme dissolutions to the reaction substrate. Immobilization method used in this study was adsorption method, using specific lipase from Aspergillus oryzae. Lipase was partially purified from the culture supernatant of Aspergillus oryzae. Enzyme was immobilized by adsorbed on silica gel. Studies on free and immobilized lipase systems for determination of optimum pH, optimum temperature, thermal stability and reusability were carried out. The results showed that free lipase had optimum pH 8,2 and optimum temperature 35 °C while the immobilized lipase had optimum 8,2 and optimum temperature 45 °C. The thermal stability of the immobilized lipase, relative to that of the free lipase, was markedly increased. The immobilized lipase can be reused for at least six times.

  19. Determination of volatile components in fermented soybean prepared by a co-culture of Bacillus subtilis and Rhizopus oligosporus

    Directory of Open Access Journals (Sweden)

    Chukeatirote, E.,

    2017-07-01

    Full Text Available Fermented soybeans are traditional foods widely consumed in many countries (i.e., Natto in Japan, Jang in Korea, Kinema in India, Douichi in China, and Thua Nao in Thailand. In this study, an attempt was made with an expectation to improve the fermentation process using a co-culture of Bacillus subtilis and Rhizopus oligosporus. Initially, the raw soybeans were washed, sterilized by autoclaving, and inoculated with two inocula; for this, three different ratios between B. subtilis and R. oligosporus used were 100:0, 50:50, and 0:100. The fermentation was then carried out at 30°C for 3 days. The volatile compounds in the non-fermented and the fermented soybean products were determined by gas chromatography/ mass spectrometry (GC/MS and extracted using a solid phase microextraction (SPME technique. In total, 165 compounds were identified in the non-fermented and the fermented soybean products. For the non-fermented products, the predominant volatile compounds were alcohols (25.81%, aldehydes (13.64%, acids and esters (7.57%, furans (6.13% and ketones (0.88%. In contrast, the major volatiles compounds presented in the fermented soybeans were as follows: i The treatment of 100:0 consisted of acids and esters (35.89%, alcohols (14.55%, aldehydes (8.72%, ketones (4.97%, pyrazines (4.87%, and furans (4.22%; ii 50:50 comprised of acids and esters (55.62%, alcohols (16.22%, aldehydes (7.80%, pyrazine (3.65%, ketones (2.55%, furans (1.67%, and aromatic compounds (1.46%; and iii 0:100 included acids and esters (66.50%, alcohols (15.44%, aldehydes (2.59%, ketones (2.72%, furans (1.89%, aromatic compounds (1.80%, pyrazines (1.35%, and sulphur containing compounds (0.24% respectively.

  20. High ethanol yields using Aspergillus oryzae koji and corn media

    Energy Technology Data Exchange (ETDEWEB)

    Ziffer, J.; Iosif, M.C.

    1982-01-01

    High ethanol and stillage solids were achieved using whole corn mashes. Ethanol yields of 14% (98.5% of theory) and stillage levels of approximately 23% were obtained in 74-90 hours using mild acid pretreatment with A. oryzae wheat bran koji saccharification. High ethanol yields were also obtained with bacterial amylase, instead of the acid treatment, when the sterilization step was omitted. The implications of ethanol fermentation process modifications are explored.

  1. PdeH, a high-affinity cAMP phosphodiesterase, is a key regulator of asexual and pathogenic differentiation in Magnaporthe oryzae.

    Directory of Open Access Journals (Sweden)

    Ravikrishna Ramanujam

    2010-05-01

    Full Text Available Cyclic AMP-dependent pathways mediate the communication between external stimuli and the intracellular signaling machinery, thereby influencing important aspects of cellular growth, morphogenesis and differentiation. Crucial to proper function and robustness of these signaling cascades is the strict regulation and maintenance of intracellular levels of cAMP through a fine balance between biosynthesis (by adenylate cyclases and hydrolysis (by cAMP phosphodiesterases. We functionally characterized gene-deletion mutants of a high-affinity (PdeH and a low-affinity (PdeL cAMP phosphodiesterase in order to gain insights into the spatial and temporal regulation of cAMP signaling in the rice-blast fungus Magnaporthe oryzae. In contrast to the expendable PdeL function, the PdeH activity was found to be a key regulator of asexual and pathogenic development in M. oryzae. Loss of PdeH led to increased accumulation of intracellular cAMP during vegetative and infectious growth. Furthermore, the pdeHDelta showed enhanced conidiation (2-3 fold, precocious appressorial development, loss of surface dependency during pathogenesis, and highly reduced in planta growth and host colonization. A pdeHDelta pdeLDelta mutant showed reduced conidiation, exhibited dramatically increased (approximately 10 fold cAMP levels relative to the wild type, and was completely defective in virulence. Exogenous addition of 8-Br-cAMP to the wild type simulated the pdeHDelta defects in conidiation as well as in planta growth and development. While a fully functional GFP-PdeH was cytosolic but associated dynamically with the plasma membrane and vesicular compartments, the GFP-PdeL localized predominantly to the nucleus. Based on data from cAMP measurements and Real-Time RTPCR, we uncover a PdeH-dependent biphasic regulation of cAMP levels during early and late stages of appressorial development in M. oryzae. We propose that PdeH-mediated sustenance and dynamic regulation of cAMP signaling

  2. Transcriptome analysis of WRKY gene family in Oryza officinalis Wall ex Watt and WRKY genes involved in responses to Xanthomonas oryzae pv. oryzae stress.

    Science.gov (United States)

    Jiang, Chunmiao; Shen, Qingxi J; Wang, Bo; He, Bin; Xiao, Suqin; Chen, Ling; Yu, Tengqiong; Ke, Xue; Zhong, Qiaofang; Fu, Jian; Chen, Yue; Wang, Lingxian; Yin, Fuyou; Zhang, Dunyu; Ghidan, Walid; Huang, Xingqi; Cheng, Zaiquan

    2017-01-01

    Oryza officinalis Wall ex Watt, a very important and special wild rice species, shows abundant genetic diversity and disease resistance features, especially high resistance to bacterial blight. The molecular mechanisms of bacterial blight resistance in O. officinalis have not yet been elucidated. The WRKY transcription factor family is one of the largest gene families involved in plant growth, development and stress response. However, little is known about the numbers, structure, molecular phylogenetics, and expression of the WRKY genes under Xanthomonas oryzae pv. oryzae (Xoo) stress in O. officinalis due to lacking of O. officinalis genome. Therefore, based on the RNA-sequencing data of O. officinalis, we performed a comprehensive study of WRKY genes in O. officinalis and identified 89 OoWRKY genes. Then 89 OoWRKY genes were classified into three groups based on the WRKY domains and zinc finger motifs. Phylogenetic analysis strongly supported that the evolution of OoWRKY genes were consistent with previous studies of WRKYs, and subgroup IIc OoWRKY genes were the original ancestors of some group II and group III OoWRKYs. Among the 89 OoWRKY genes, eight OoWRKYs displayed significantly different expression (>2-fold, pWRKY family of transcription factors in O.officinalis. Insight was gained into the classification, evolution, and function of the OoWRKY genes, revealing the putative roles of eight significantly different expression OoWRKYs in Xoo strains PXO99 and C5 stress responses in O.officinalis. This study provided a better understanding of the evolution and functions of O. officinalis WRKY genes, and suggested that manipulating eight significantly different expression OoWRKYs would enhance resistance to bacterial blight.

  3. A novel non-thermostable deuterolysin from Aspergillus oryzae.

    Science.gov (United States)

    Maeda, Hiroshi; Katase, Toru; Sakai, Daisuke; Takeuchi, Michio; Kusumoto, Ken-Ichi; Amano, Hitoshi; Ishida, Hiroki; Abe, Keietsu; Yamagata, Youhei

    2016-09-01

    Three putative deuterolysin (EC 3.4.24.29) genes (deuA, deuB, and deuC) were found in the Aspergillus oryzae genome database ( http://www.bio.nite.go.jp/dogan/project/view/AO ). One of these genes, deuA, was corresponding to NpII gene, previously reported. DeuA and DeuB were overexpressed by recombinant A. oryzae and were purified. The degradation profiles against protein substrates of both enzymes were similar, but DeuB showed wider substrate specificity against peptidyl MCA-substrates compared with DeuA. Enzymatic profiles of DeuB except for thermostability also resembled those of DeuA. DeuB was inactivated by heat treatment above 80° C, different from thermostable DeuA. Transcription analysis in wild type A. oryzae showed only deuB was expressed in liquid culture, and the addition of the proteinous substrate upregulated the transcription. Furthermore, the NaNO3 addition seems to eliminate the effect of proteinous substrate for the transcription of deuB.

  4. Jewelry boxes contaminated by Aspergillus oryzae: an occupational health risk?

    Science.gov (United States)

    Bellanger, Anne-Pauline; Roussel, Anaïs; Millon, Laurence; Delaforge, Marcel; Reboux, Gabriel

    2012-01-01

    In 2009, 100,000 jewelry boxes, manufactured in China, were delivered to a jewelry manufacturer in Besançon, France. All the boxes were contaminated by mold. Because the workers refused to handle these jewelry boxes, the company contacted our laboratory to determine how to deal with the problem. Three choices were available: (1) decontaminate the boxes, (2) return the boxes to the Chinese manufacturer, or (3) destroy the entire shipment. Based on microscopic identification, the culture analysis was positive for A. oryzae. This could not be confirmed by molecular techniques because of the genetic proximity of A. oryzae and A. flavus. Because A. flavus can produce aflatoxins, we tested for them using mass spectrometry. Aflatoxins B1, B2, G1, G2, and M1 were not detected; however, given the specifics of this situation, we could not discard the possibility of the presence of other aflatoxins, such as P1, B3, GM2, and ethoxyaflatoxin B2. We concluded that the contamination by A. oryzae was probably due to food products. However, because of the possible presence of aflatoxins, occupational health risks could not be entirely ruled out. The decision was therefore taken to destroy all the jewelry boxes by incineration. To avoid a similar situation we propose: (1) to maintain conditions limiting mold contamination during production (not eating on the work site, efficient ventilation systems); (2) to desiccate the products before sending them; and (3) to closely control the levels of dampness during storage and transport.

  5. A spindle pole antigen gene MoSPA2 is important for polar cell growth of vegetative hyphae and conidia, but is dispensable for pathogenicity in Magnaporthe oryzae.

    Science.gov (United States)

    Li, Chao; Yang, Jun; Zhou, Wei; Chen, Xiao-Lin; Huang, Jin-Guang; Cheng, Zhi-Hua; Zhao, Wen-Sheng; Zhang, Yan; Peng, You-Liang

    2014-11-01

    Spa2 is an important component of the multiprotein complex polarisome, which is involved in the establishment, maintenance, termination of polarized cell growth and is important for defining tip growth of filamentous fungi. In this study, we isolated an insertional mutant of the rice blast fungus Magnaporthe oryzae that formed smaller colony and conidia compared with the wild type. In the mutant, a spindle pole antigen gene MoSPA2 was disrupted by the integration of an exogenous plasmid. Targeted gene deletion and complementation assays demonstrated the gene disruption was responsible for the defects of the insertional mutant. Interestingly, the MoSpa2-GFP fusion protein was found to accumulate as a spot at hyphal tips, septa of hyphae and conidial tip cells where germ tubes are usually produced, but not in appressoria, infection hyphae or at the septa of conidia. Furthermore, the deletion mutants of MoSPA2 exhibited slower hyphal tip growth, more hyphal branches, and smaller size of conidial tip cells. However, MoSPA2 is not required for plant infection. These results indicate that MoSPA2 is required for vegetative hyphal growth and maintaining conidium morphology and that spotted accumulation of MoSpa2 is important for its functions during cell polar growth.

  6. Impact of Engineered Nanoparticles on Virulence of Xanthomonas oryzae pv oryzae and on Rice Sensitivity at its Infection

    Directory of Open Access Journals (Sweden)

    Giuliano Degrassi

    2014-12-01

    Full Text Available The present work of nanocotoxicity wants to propose a new plant model starting from the rice plant. The model takes into consideration the impact of engineered nanoparticles (Ag, Co, Ni, CeO2, Fe3O4, TiO2 on rice plants that were weakened by infections of Xanthomonas oryzae pv oryzae bacteria. The results indicate that some NPs increase the rice sensitivity to the pathogen while others decrease the virulence of the pathogen towards rice. No-enrichment in component metal concentration is detected in above organs of rice, with exception of Ni-NPs treatment. An imbalance of major elements in infected rice crops treated with NPs was investigated.

  7. Induction of resistance to blast disease (Pyricularia oryzae) in the high yielding variety, Ratna (IR8xTKM6)

    International Nuclear Information System (INIS)

    Kaur, S.; Padmanabhan, S.Y.; Kaur, P.

    1977-01-01

    The high yielding variety, Ratna (IR8 x TKM6), susceptible to blast disease (Pyricularia oryzae Cav.), was taken up for induction of resistance to the disease through EMS treatment. The seeds of individual M 1 plants were harvested and grown as M 2 generation in a ''uniform blast nursery''. The scoring and classification of blast reaction was done according to the method described by Padmanabhan and Ganguly. The seeds of ''resistant'' selections and ''susceptible'' selections were harvested, grown and tested again in the ''uniform blast nursery'' for M 3 , M 4 and M 5 generations. Ratna (untreated) developed 'B', 'C', and 'D' type of spots whereas the EMS-treated populations in all generations, i.e. M 2 -M 4 , developed 'O', 'A' and 'E' types of spot, in addition to 'B', 'C' and 'D' types, in both resistant and susceptible selections. This indicated that the chemical mutagen EMS induced variability in both negative and positive directions. In M 5 generation, 50 out of 1500 originally selected lines were found to be breeding true for disease resistance. Some mutants retain the grain characters of Ratna, and the high yield. The mutagen treatment also induced variability in grain characters. Ratna has a long slender grain. Some mutants have medium slender, short bold or long bold grain. (author)

  8. Aspergillus oryzae NRRL 35191 from coffee, a non-toxigenic endophyte with the ability to synthesize kojic acid

    Science.gov (United States)

    Aspergillus oryzae was isolated as an endophyte from coffee leaves and found to produce kojic acid in culture. When inoculated in cacao seedlings (Theobroma cacao L.), A. oryzae grew endophytically and synthesize kojic acid in planta. Cacao seedlings inoculated with A. oryzae produced higher levels...

  9. Auxin-dependent microtubule responses and seedling development are affected in a rice mutant resistant to EPC

    International Nuclear Information System (INIS)

    Nick, P.; Yatou, O.; Furuya, M.; Lambert, A.M.

    1994-01-01

    Mutants in rice (Oryza sativa L. cv. japonica) were used to study the role of the cytoskeleton in signal-dependent morphogenesis. Mutants obtained by gamma ray irradiation were selected that failed to show inhibition of coleoptile elongation by the anti microtubular drug ethyl-N-phenylcarbamate (EPC). The mutation EPC-Resistant 31 (ER31), isolated from such a screen, caused lethality in putatively homozygous embryos. Heterozygotes exhibited drug resistance, impaired development of crown roots, and characteristic changes in the pattern of cell elongation: cell elongation was enhanced in mesocotyls and leaf sheaths, but inhibited in coleoptiles. The orientation of cortical microtubules changed correspondingly: for etiolated seedlings, compared with the wild-type, they were more transverse with respect to the long cell axis in mesocotyls and leaf sheaths, but more longitudinal in coleoptiles. In mutant coleoptiles, in contrast to wild-type, microtubules did not reorient in response to auxin, and their response to microtubule-eliminating and microtubule-stabilizing drugs was conspicuously reduced. In contrast, they responded normally to other stimuli such as gibberellins or red light. Auxin sensitivity as assayed by the dose-response for callus induction did not show any significant differences between wild-type and mutant. The mutant phenotype is interpreted in terms of an interrupted link between auxin-triggered signal transduction and microtubule reorientation. (author)

  10. The rice XA21 ectodomain fused to the Arabidopsis EFR cytoplasmic domain confers resistance to Xanthomonas oryzae pv. oryzae.

    Science.gov (United States)

    Thomas, Nicholas C; Oksenberg, Nir; Liu, Furong; Caddell, Daniel; Nalyvayko, Alina; Nguyen, Yen; Schwessinger, Benjamin; Ronald, Pamela C

    2018-01-01

    Rice ( Oryza sativa ) plants expressing the XA21 cell-surface receptor kinase are resistant to Xanthomonas oryzae pv. oryzae (Xoo) infection. We previously demonstrated that expressing a chimeric protein containing the ELONGATION FACTOR Tu RECEPTOR (EFR) ectodomain and the XA21 endodomain (EFR:XA21) in rice does not confer robust resistance to Xoo . To test if the XA21 ectodomain is required for Xoo resistance, we produced transgenic rice lines expressing a chimeric protein consisting of the XA21 ectodomain and EFR endodomain (XA21:EFR) and inoculated these lines with Xoo . We also tested if the XA21:EFR rice plants respond to a synthetic sulfated 21 amino acid derivative (RaxX21-sY) of the activator of XA21-mediated immunity, RaxX. We found that five independently transformed XA21:EFR rice lines displayed resistance to Xoo as measured by lesion length analysis, and showed that five lines share characteristic markers of the XA21 defense response (generation of reactive oxygen species and defense response gene expression) after treatment with RaxX21-sY. Our results indicate that expression of the XA21:EFR chimeric receptor in rice confers resistance to Xoo . These results suggest that the endodomain of the EFR and XA21 immune receptors are interchangeable and the XA21 ectodomain is the key determinant conferring robust resistance to Xoo .

  11. Ecogeographic variation in the morphology of two Asian wild rice species Oryza nivara and O. ruftipogon.

    NARCIS (Netherlands)

    Banaticla, M.C.N.; Sosef, M.S.M.; McNally, K.L.; Sackville Hamilton, R.; Berg, van den R.G.

    2013-01-01

    To search for variation patterns and diagnostic features between Asian wild rice species, several numerical methods were applied to phenotypic data obtained from 116 accessions representing sympatric populations of Oryza nivara and Oryza rufipogon from tropical continental Asia and O. rufipogon

  12. Characterization of field isolates of Magnaporthe oryzae with mating type, DNA fingerprinting, and pathogenicity assays

    Science.gov (United States)

    Due to the harmful nature of the rice blast fungus, Magnaporthe oryzae, it is beneficial to characterize field isolates to help aid in the deployment of resistance (R) genes in rice. In the present study, 190 field isolates of M. oryzae, collected from rice fields of Yunnan province in China, were a...

  13. Identification of secreted proteins of Aspergillus oryzae associated with growth on solid cereal substrates

    NARCIS (Netherlands)

    Biesebeke, R. te; Boussier, A.; Biezen, N. van; Hondel, C.A.M.J.J. van den; Punt, P.J.

    2006-01-01

    Filamentous growth of Aspergillus oryzae on solid cereal substrates involves secretion of substrate converting enzymes and a solid substrate specific polarised hyphal growth phenotype. To identify proteins produced under these specific conditions, the extracts of A. oryzae grown on wheat-based media

  14. Correlation between temperature and phenology prediction error in rice (Oryza sativa L.)

    NARCIS (Netherlands)

    Oort, van P.A.J.; Zhang, T.; Vries, de M.E.; Heinemann, A.B.; Meinke, H.B.

    2011-01-01

    For rice (Oryza sativa L.), simulation models like ORYZA2000 and CERES-Rice have been used to explore adaptation options to climate change and weather-related stresses (drought, heat). Output of these models is very sensitive to accurate modelling of crop development, i.e. phenology. What has to

  15. Development and Identification of Introgression Lines from Cross of Oryza sativa and Oryza minuta

    Institute of Scientific and Technical Information of China (English)

    GUO Si-bin; WEI Yu; LI Xiao-qiong; LIU Kai-qiang; HUANG Feng-kuan; CHEN Cai-hong; GAO Guo-qing

    2013-01-01

    Introgression line population is effectively used in mapping quantitative trait loci (QTLs),identifying favorable genes,discovering hidden genetic variation,evaluating the action or interaction of QTLs in multiple conditions and providing the favorable experimental materials for plant breeding and genetic research.In this study,an advanced backcross and consecutive selfing strategy was used to develop introgression lines (ILs),which derived from an accession of Oryza minuta (accession No.101133) with BBCC genome,as the donor,and an elite indica cultivar IR24 (O.sativa),as the recipient.Introgression segments from O.minuta were screened using 164 polymorphic simple sequence repeat (SSR) markers in the genome of each IL.Introgressed segments carried by 131 ILs covered the whole O.sativa genome.The average number of homozygous O.minuta segments per introgression line was about 9.99.The average length of introgressed segments was approximate 14.78 cM,and about 79.64%of these segments had sizes less than 20 cM.In the genome of each introgression line,the O.minuta chromosomal segments harbored chromosomal fragments of O.sativa ranging from 1.15% to 27.6%,with an overall average of 8.57%.At each locus,the ratio of substitution of O.minuta alleles had a range of 1.5%-25.2%,with an average of 8.3% Based on the evaluation of the phenotype of these ILs,a wide range of alterations in morphological and yield-related traits were found.After inoculation,ILs 41,11 and 7 showed high resistance to bacterial blight,brown planthopper and whitebacked planthopper,respectively.These O.minuta-O.sativa ILs will serve as genetic materials for identifying and using favorable genes from O.minuta.

  16. Azospirillum brasilense and Azospirillum lipoferum Hydrolyze Conjugates of GA20 and Metabolize the Resultant Aglycones to GA1 in Seedlings of Rice Dwarf Mutants1

    Science.gov (United States)

    Cassán, Fabricio; Bottini, Rubén; Schneider, Gernot; Piccoli, Patricia

    2001-01-01

    Azospirillum species are plant growth-promotive bacteria whose beneficial effects have been postulated to be partially due to production of phytohormones, including gibberellins (GAs). In this work, Azospirillum brasilense strain Cd and Azospirillum lipoferum strain USA 5b promoted sheath elongation growth of two single gene GA-deficient dwarf rice (Oryza sativa) mutants, dy and dx, when the inoculated seedlings were supplied with [17,17-2H2]GA20-glucosyl ester or [17,17- 2H2]GA20-glucosyl ether. Results of capillary gas chromatography-mass spectrometry analysis show that this growth was due primarily to release of the aglycone [17,17-2H2]GA20 and its subsequent 3β-hydroxylation to [17,17-2H2]GA1 by the microorganism for the dy mutant, and by both the rice plant and microorganism for the dx mutant. PMID:11299384

  17. Distinct enzymatic and cellular characteristics of two secretory phospholipases A2 in the filamentous fungus Aspergillus oryzae.

    Science.gov (United States)

    Nakahama, Tomoyuki; Nakanishi, Yoshito; Viscomi, Arturo R; Takaya, Kohei; Kitamoto, Katsuhiko; Ottonello, Simone; Arioka, Manabu

    2010-04-01

    Microbial secretory phospholipases A(2) (sPLA(2)s) are among the last discovered and least known members of this functionally diverse family of enzymes. We analyzed here two sPLA(2)s, named sPlaA and sPlaB, of the filamentous ascomycete Aspergillus oryzae. sPlaA and sPlaB consist of 222 and 160 amino acids, respectively, and share the conserved Cys and catalytic His-Asp residues typical of microbial sPLA(2)s. Two sPLA(2)s differ in pH optimum, Ca(2+) requirement and expression profile. The splaA mRNA was strongly upregulated in response to carbon starvation, oxidative stress and during conidiation, while splaB was constitutively expressed at low levels and was weakly upregulated by heat shock. Experiments with sPLA(2) overexpressing strains demonstrated that two enzymes produce subtly different phospholipid composition variations and also differ in their subcellular localization: sPlaA is most abundant in hyphal tips and secreted to the medium, whereas sPlaB predominantly localizes to the ER-like intracellular compartment. Both sPLA(2) overexpressing strains were defective in conidiation, which was more pronounced for sPlaB overexpressors. Although no major morphological abnormality was detected in either DeltasplaA or DeltasplaB mutants, hyphal growth of DeltasplaB, but not that of DeltasplaA, displayed increased sensitivity to H(2)O(2) treatment. These data indicate that two A. oryzae sPLA(2) enzymes display distinct, presumably non-redundant, physiological functions.

  18. Improvement of heterologous protein production in Aspergillus oryzae by RNA interference with alpha-amylase genes.

    Science.gov (United States)

    Nemoto, Takashi; Maruyama, Jun-ichi; Kitamoto, Katsuhiko

    2009-11-01

    Aspergillus oryzae RIB40 has three alpha-amylase genes (amyA, amyB, and amyC), and secretes alpha-amylase abundantly. However, large amounts of endogenous secretory proteins such as alpha-amylase can compete with heterologous protein in the secretory pathway and decrease its production yields. In this study, we examined the effects of suppression of alpha-amylase on heterologous protein production in A. oryzae, using the bovine chymosin (CHY) as a reporter heterologous protein. The three alpha-amylase genes in A. oryzae have nearly identical DNA sequences from those promoters to the coding regions. Hence we performed silencing of alpha-amylase genes by RNA interference (RNAi) in the A. oryzae CHY producing strain. The silenced strains exhibited a reduction in alpha-amylase activity and an increase in CHY production in the culture medium. This result suggests that suppression of alpha-amylase is effective in heterologous protein production in A. oryzae.

  19. Production of L-lactic acid from Cassava peel wastes using single and mixed cultures of Rhizopus oligosporus and Lactobacillus plantarum

    Directory of Open Access Journals (Sweden)

    Nwokoro Ogbonnaya

    2014-01-01

    Full Text Available Production of L-lactic acid using cultures of Rhizopus oligosporus and Lactobacillus plantarum was investigated. Cassava peels were hydrolyzed by boiling for 1 h in either NaOH or HCl solutions followed by neutralization to a pH of 6.2. Reducing sugar produced from the hydrolysates increased with increasing concentrations of alkali or acid. Samples hydrolyzed with HCl produced a maximum reducing sugar concentration of 402 mg/g substrate while alkali hydrolyzed samples produced a maximum reducing sugar concentration of 213 mg/g substrate. Hydrolysates were amended with 0.5% ammonium sulphate solution and inoculated with either single or mixed cultures of Rhizopus oligosporus and Lactobacillus plantarum and incubated for 48 h for lactic acid production. The best lactic acid production of 50.2 g/100g substrate was observed in a mixed culture fermentation of acid hydrolyzed peels. Mixed culture fermentation of alkali hydrolyzed peels produced a maximum lactic acid concentration of 36.4 g/100g substrate. Un hydrolyzed cassava peels inoculated with a mixed culture of the microorganisms produced only 4.6 g/100g substrate. This work reports an efficient use of cassava peels for bio-product formation through microbial fermentation.

  20. Silver nanoparticle production by Rhizopus stolonifer and its antibacterial activity against extended spectrum β-lactamase producing (ESBL) strains of Enterobacteriaceae

    International Nuclear Information System (INIS)

    Banu, Afreen; Rathod, Vandana; Ranganath, E.

    2011-01-01

    Highlights: → Silver nanoparticle production by using Rhizopus stolonifer. → Antibacterial activity of silver nanoparticles against extended spectrum β-lactamase producing (ESBL) strains of Enterobacteriaceae. → Synergistic effect of antibiotics with silver nanoparticles towards ESBL-strains. → Characterization of silver nanoparticles made by UV-vis spectra, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transformed infrared (FTIR) spectroscopy, atomic force microscopy (AFM). -- Abstract: This report focuses on the synthesis of silver nanoparticles using the fungus, Rhizopus stolonifer and its antimicrobial activity. Research in nanotechnology highlights the possibility of green chemistry pathways to produce technologically important nanomaterials. Characterization of newly synthesized silver nanoparticles was made by UV-visible absorption spectroscopy, scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier transform infrared (FTIR) spectroscopy and atomic force microscope (AFM). TEM micrograph revealed the formation of spherical nanoparticles with size ranging between 3 and 20 nm. The biosynthesized silver nanoparticles (AgNPs) showed excellent antibacterial activity against ESBL-strains which includes E. coli, Proteus. sp. and Klebsiella sp.

  1. Influence of the Oil Pequi in the Growth Mycelial and Sporulation of Colletotrichum Musae and Growth Micelial Of Rhizopus sp. in vitro.

    Directory of Open Access Journals (Sweden)

    B. L. Mendes

    2013-07-01

    Full Text Available Abstract: The anthracnose caused by Colletotrichum musae and soft rot caused by Rhizopus sp are post-harvest diseases that influenced quality of exported fruits. To control these diseases fungicides are used, but in light of these waste products in the fruit and the environment, alternative control methods such as using biofungicides have been studied. The objective of this study was to evaluate the effect of pequi oil on mycelia growth and sporulation of Colletotrichum musae and mycelia growth of Rhizopus sp. in vitro. The oil was added in aliquots of 5, 10, 15, 20, 25, and 50L in the center of Petri dishes containing approximately 15mL of Potato-Dextrose-ar (PDA and distributed over the surface of the medium with Drigalskys handle. After 24 hours, a disc of 8mm diameter from mycelium of fungi was peaked to the center of the plates. As a control, were used Petri dishes containing only PDA. Five replicates were used for each aliquot. After analysis, it was concluded that the pequi oil is ineffective for controlling these pathogens because induced mycelium growth and sporulation.Key Words: Phytopathogens, alternative control, anthracnose, soft rot

  2. Silver nanoparticle production by Rhizopus stolonifer and its antibacterial activity against extended spectrum {beta}-lactamase producing (ESBL) strains of Enterobacteriaceae

    Energy Technology Data Exchange (ETDEWEB)

    Banu, Afreen [Department of Microbiology, Gulbarga University, Gulbarga 585106, Karnataka (India); Rathod, Vandana, E-mail: drvandanarathod@rediffmail.com [Department of Microbiology, Gulbarga University, Gulbarga 585106, Karnataka (India); Ranganath, E. [Department of Microbiology, Gulbarga University, Gulbarga 585106, Karnataka (India)

    2011-09-15

    Highlights: {yields} Silver nanoparticle production by using Rhizopus stolonifer. {yields} Antibacterial activity of silver nanoparticles against extended spectrum {beta}-lactamase producing (ESBL) strains of Enterobacteriaceae. {yields} Synergistic effect of antibiotics with silver nanoparticles towards ESBL-strains. {yields} Characterization of silver nanoparticles made by UV-vis spectra, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transformed infrared (FTIR) spectroscopy, atomic force microscopy (AFM). -- Abstract: This report focuses on the synthesis of silver nanoparticles using the fungus, Rhizopus stolonifer and its antimicrobial activity. Research in nanotechnology highlights the possibility of green chemistry pathways to produce technologically important nanomaterials. Characterization of newly synthesized silver nanoparticles was made by UV-visible absorption spectroscopy, scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier transform infrared (FTIR) spectroscopy and atomic force microscope (AFM). TEM micrograph revealed the formation of spherical nanoparticles with size ranging between 3 and 20 nm. The biosynthesized silver nanoparticles (AgNPs) showed excellent antibacterial activity against ESBL-strains which includes E. coli, Proteus. sp. and Klebsiella sp.

  3. Isolation of Mucorales from processed maize (Zea mays L.) and screening for protease activity

    OpenAIRE

    de Azevedo Santiago, Andr? Luiz Cabral Monteiro; de Souza Motta, Cristina Maria

    2008-01-01

    Mucorales were isolated from maize flour, corn meal and cooked cornflakes using surface and depth plate methods. Rhizopus oryzae, Circinella muscae, Mucor subtilissimus, Mucor hiemalis f. hiemalis, Syncephalastrum racemosum, Rhizopus microsporus var. chinensis and Absidia cylindrospora showed protease activity.

  4. Mutant power: using mutant allele collections for yeast functional genomics.

    Science.gov (United States)

    Norman, Kaitlyn L; Kumar, Anuj

    2016-03-01

    The budding yeast has long served as a model eukaryote for the functional genomic analysis of highly conserved signaling pathways, cellular processes and mechanisms underlying human disease. The collection of reagents available for genomics in yeast is extensive, encompassing a growing diversity of mutant collections beyond gene deletion sets in the standard wild-type S288C genetic background. We review here three main types of mutant allele collections: transposon mutagen collections, essential gene collections and overexpression libraries. Each collection provides unique and identifiable alleles that can be utilized in genome-wide, high-throughput studies. These genomic reagents are particularly informative in identifying synthetic phenotypes and functions associated with essential genes, including those modeled most effectively in complex genetic backgrounds. Several examples of genomic studies in filamentous/pseudohyphal backgrounds are provided here to illustrate this point. Additionally, the limitations of each approach are examined. Collectively, these mutant allele collections in Saccharomyces cerevisiae and the related pathogenic yeast Candida albicans promise insights toward an advanced understanding of eukaryotic molecular and cellular biology. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  5. Evidence for biotrophic lifestyle and biocontrol potential of dark septate endophyte Harpophora oryzae to rice blast disease.

    Directory of Open Access Journals (Sweden)

    Zhen-Zhu Su

    Full Text Available The mutualism pattern of the dark septate endophyte (DSE Harpophora oryzae in rice roots and its biocontrol potential in rice blast disease caused by Magnaporthe oryzae were investigated. Fluorescent protein-expressing H. oryzae was used to monitor the colonization pattern. Hyphae invaded from the epidermis to the inner cortex, but not into the root stele. Fungal colonization increased with root tissue maturation, showing no colonization in the meristematic zone, slight colonization in the elongation zone, and heavy colonization in the differentiation zone. H. oryzae adopted a biotrophic lifestyle in roots accompanied by programmed cell death. Real-time PCR facilitated the accurate quantification of fungal growth and the respective plant response. The biocontrol potential of H. oryzae was visualized by inoculation with eGFP-tagged M. oryzae in rice. H. oryzae protected rice from M. oryzae root invasion by the accumulation of H2O2 and elevated antioxidative capacity. H. oryzae also induced systemic resistance against rice blast. This systemic resistance was mediated by the OsWRKY45-dependent salicylic acid (SA signaling pathway, as indicated by the strongly upregulated expression of OsWRKY45. The colonization pattern of H. oryzae was consistent with the typical characteristics of DSEs. H. oryzae enhanced local resistance by reactive oxygen species (ROS and high antioxidative level and induced OsWRKY45-dependent SA-mediated systemic resistance against rice blast.

  6. Nuclear and original DNA application in Oryza taxonomy and phylogeny

    International Nuclear Information System (INIS)

    Romero, Gabriel O.

    1998-01-01

    Conventional taxonomy and phylogeny of germplasm are based on the tedious characterization of morphological variation. The ability to assay DNA variation that underlies morphological variation offers great promise as a convenient alternative for the genetic characterization of germplasm. Restriction fragment length polymorphism (RFLP) was used to survey DNA variation in 22 species of the genus Oryza. At the ribosomal DNA (rDNA) multigene family, 15 rDNA spacer length (sl) variants were identified using restriction enzyme Sst1 and wheatrDNA unit as probe. Particular sl variants predominated in certain isozyme groups of O. sativa, indicating a potential of sl ploymorphism in varietal classification. The distribution of sl variants supports the origin of O. sativa and O. nivara from O. rufipogon, and that O. spontanea arose from introgressions among O. sativa, O. nivara, and O. rufipogon. The distribution also suggests that the CCgenome, of all the genomes in the Officinalis complex, may be closest to the Sativa complex genomes, and it affirms the genetic position of the Officinalis complex intermediate between the Sativa and Ridleyi complexes. Variation at the Oryza organelle genomes was probed with a maize mitochondrial gene, atpA, a wheat chloroplast inverted repeat segment, p6. Results indicated that the complexes can be differentiated by their mitochondrial genome, but not their chloroplast genome when digested by Sst1 or BamH1. Therefore, the natural DNA variation in the nuclear and mitochondrial genomes has demonstrated great potential in complementing the conventional basis of taxa classification and phylogeny in the genus Oryza. (Author)

  7. Research on the ultrafast fluorescence property of thylakoid membranes of the wild-type and mutant rice

    Science.gov (United States)

    Ren, Zhao-Yu; Xu, Xiao-Ming; Wang, Shui-Cai; Xin, Yue-Yong; He, Jun-Fang; Hou, Xun

    2003-10-01

    A high yielding rice variety mutant (Oryza sativa L., Zhenhui 249) with low chlorophyll b (Chl b) has been discovered in natural fields. It has a quality character controlled by a pair of recessive genes (nuclear gene). The partial loss of Chl b in content affects the efficiency of light harvest in a light harvest complex (LHC), thus producing the difference of the exciting energy transfer and the efficiency of photochemistry conversion between the mutant and wild-type rice in photosynthetic unit. The efficiency of utilizing light energy is higher in the mutant than that in the wild-type rice relatively. For further discussion of the above-mentioned difference and learning about the mechanism of the increase in the photochemical efficiency of the mutant, the pico-second resolution fluorescence spectrum measurement with delay-frame-scanning single photon counting technique is adopted. Thylakoid membranes of the mutant and the wild-type rice are excited by an Ar+ laser with a pulse width of 120 ps, repetition rate of 4 MHz and wavelength of 514 nm. Compared with the time and spectrum property of exciting fluorescence, conclusions of those ultrafast dynamic experiments are: 1) The speeds of the exciting energy transferred in photo-system I are faster than that in photo-system II in both samples. 2) The speeds of the exciting energy transfer of mutant sample are faster than those of the wild-type. This might be one of the major reasons why the efficiency of photosynthesis is higher in mutant than that in the wild-type rice.

  8. Kinetics of alpha-amylase secretion in Aspergillus oryzae

    DEFF Research Database (Denmark)

    Henriksen, Anne Laurence Santerre; Carlsen, Morten; Bang de, H.

    1999-01-01

    -chase experiments were carried out to investigate the alpha-amylase secretion kinetics in A. oryzae. No unglycosylated alpha-amylase was detected neither intracellularly nor extracellularly demonstrating that glycosylation was not the rate controlling step in the secretory pathway. The pulse chase experiments...... indicated that there are two pools of intracellular alpha-amylase: a fast secreted and a slow secreted. The secretion of those two pools were described with a kinetic model, which was fitted to the pulse chase experiments. (C) 1999 John Wiley & Sons, Inc. Biotechnol Bioeng 65: 76-82, 1999....

  9. Sensory acceptability evaluation of irradiated rice, oryza sativa indica

    International Nuclear Information System (INIS)

    Loaharanu, S.; Sutantawong, M.; Ungsunanatawiwat, A.

    1971-01-01

    The non-glutinous and glutinous types of polished rice, Oryza sativa indica were subjected to gamma rays at ambient temperature and stored at 27+-1 0 C for one week. The irradiated rice was cooked and tasted by members of trained panel. Using Hedonic scale and Triangle test, the acceptability of irradiated rice was justified. Gamma irradiation up to 100 krads did not significantly cause off-color, off-odor and off flavor in irradiated non-glutino rice. Glutinous rice irradiated at 60 krads could not be significantly differentiated from non-irradiated sample

  10. Gamma radiation effects in Sitophilus oryzae (Linne, 1763) (Coleoptera, Curculionidae)

    International Nuclear Information System (INIS)

    Pacheco, J.M.

    1973-01-01

    Lethal effects were studied for the egg, larval and pupal stages as well as sterilization of adults of Sitophilus oryzae (L.) by the application of gamma radiation. Irradiation of pupae with an estimated dosis of 7887 ± 158 rad inhibits adult emergency. Hypotheses have been suggested that the apparent density and (or) nutrient value of food substrates decisively influence the sterilizing dosis for this insect. Thus, in rice and maize which are apparently denser and (or) of higher nutrient value than maccaroni, insects are sterilized by a dosis of 7 krad, while in maccaroni the sterilizing dosis decreases to 5 krad. (author)

  11. Mutant genes in pea breeding

    International Nuclear Information System (INIS)

    Swiecicki, W.K.

    1990-01-01

    Full text: Mutations of genes Dpo (dehiscing pods) and A (anthocyanin synthesis) played a role in pea domestication. A number of other genes were important in cultivar development for 3 types of usage (dry seeds, green vegetable types, fodder), e.g. fn, fna, le, p, v, fas and af. New genes (induced and spontaneous), are important for present ideotypes and are registered by the Pisum Genetics Association (PGA). Comparison of a pea variety ideotype with the variation available in gene banks shows that breeders need 'new' features. In mutation induction experiments, genotype, mutagen and method of treatment (e.g. combined or fractionated doses) are varied for broadening the mutation spectrum and selecting more genes of agronomic value. New genes are genetically analysed. In Poland, some mutant varieties with the gene afila were registered, controlling lodging by a shorter stem and a higher number of internodes. Really non-lodging pea varieties could strongly increase seed yield. But the probability of detecting a major gene for lodging resistance is low. Therefore, mutant genes with smaller influence on plant architecture are sought, to combine their effect by crossing. Promising seem to be the genes rogue, reductus and arthritic as well as a number of mutant genes not yet genetically identified. The gene det for terminal inflorescence - similarly to Vicia faba - changes plant development. Utilisation of assimilates and ripening should be better. Improvement of harvest index should give higher seed yield. A number of genes controlling disease resistance are well known (eg. Fw, Fnw, En, mo and sbm). Important in mass screening of resistance are closely linked gene markers. Pea gene banks collect respective lines, but mutants induced in highly productive cultivars would be better. Inducing gene markers sometimes seems to be easier than transfer by crossing. Mutation induction in pea breeding is probably more important because a high number of monogenic features are

  12. Two solanesyl diphosphate synthases with different subcellular localizations and their respective physiological roles in Oryza sativa.

    Science.gov (United States)

    Ohara, Kazuaki; Sasaki, Kanako; Yazaki, Kazufumi

    2010-06-01

    Long chain prenyl diphosphates are crucial biosynthetic precursors of ubiquinone (UQ) in many organisms, ranging from bacteria to humans, as well as precursors of plastoquinone in photosynthetic organisms. The cloning and characterization of two solanesyl diphosphate synthase genes, OsSPS1 and OsSPS2, in Oryza sativa is reported here. OsSPS1 was highly expressed in root tissue whereas OsSPS2 was found to be high in both leaves and roots. Enzymatic characterization using recombinant proteins showed that both OsSPS1 and OsSPS2 could produce solanesyl diphosphates as their final product, while OsSPS1 showed stronger activity than OsSPS2. However, an important biological difference was observed between the two genes: OsSPS1 complemented the yeast coq1 disruptant, which does not form UQ, whereas OsSPS2 only very weakly complemented the growth defect of the coq1 mutant. HPLC analyses showed that both OsSPS1 and OsSPS2 yeast transformants produced UQ9 instead of UQ6, which is the native yeast UQ. According to the complementation study, the UQ9 levels in OsSPS2 transformants were much lower than that of OsSPS1. Green fluorescent protein fusion analyses showed that OsSPS1 localized to mitochondria, while OsSPS2 localized to plastids. This suggests that OsSPS1 is involved in the supply of solanesyl diphosphate for ubiquinone-9 biosynthesis in mitochondria, whereas OsSPS2 is involved in providing solanesyl diphosphate for plastoquinone-9 formation. These findings indicate that O. sativa has a different mechanism for the supply of isoprenoid precursors in UQ biosynthesis from Arabidopsis thaliana, in which SPS1 provides a prenyl moiety for UQ9 at the endoplasmic reticulum.

  13. Effect of irradiation on protease production by a Philippine strain of Aspergillus oryzae (ahlburg) cohn

    International Nuclear Information System (INIS)

    Anglo, P.G.

    1974-03-01

    The Philippine strain of Aspergillus oryzae (ahlburg) cohn. was exposed to ultraviolet rays and ionizing radiation from cobalt-60 for the purpose of obtaining possible mutants or resistant strains which produce powerful proteolytic enzymes. Out of 58 isolates, only 3 gave significant proteolytic values (PV) high enough to merit further investigation. The isolates, G-10, G-110, and 23-110, were picked from plates exposed to gamma rays from cobalt-60. Optimum incubation temperature for these isolates for highest percentage of active protease was 24 0 -27 0 C. The isolates were found capable of producing active protease from the second day of incubation up to the fifth day, whereas the activity of the parent strain was retained the fourth day only. The isolates showed maximum digestive ability at 25 0 -55 0 C, giving proteolytic values of 833. The pH activity curves showed that the enzyme produced by the irradiated isolates G-10 and G-110 were very active at pH 9.0-10.0, and isolate 23-110 at pH 6.0-10.0. The parent strain revealed two pH optima, one at pH 7.5-8.5 and the other at pH 9.0-9.5. Crude enzyme powder gave activities comparable to alkalase and maxatase, commercial proteolytic enzymes imported from Belgium and Netherlands being used as component of laundry detergents by some manufacturing companies in the Philippines. The results obtained give valuable information for the commercial application of the enzyme. Since the organism can produce high yields of protease from copra meal, a by-product of the coconut industry, commerical feasibility may be envisioned in the near future

  14. A walk on the wild side: Oryza species as source for rice abiotic stress tolerance.

    Science.gov (United States)

    Menguer, Paloma Koprovski; Sperotto, Raul Antonio; Ricachenevsky, Felipe Klein

    2017-01-01

    Oryza sativa, the common cultivated rice, is one of the most important crops for human consumption, but production is increasingly threatened by abiotic stresses. Although many efforts have resulted in breeding rice cultivars that are relatively tolerant to their local environments, climate changes and population increase are expected to soon call for new, fast generation of stress tolerant rice germplasm, and current within-species rice diversity might not be enough to overcome such needs. The Oryza genus contains other 23 wild species, with only Oryza glaberrima being also domesticated. Rice domestication was performed with a narrow genetic diversity, and the other Oryza species are a virtually untapped genetic resource for rice stress tolerance improvement. Here we review the origin of domesticated Oryza sativa from wild progenitors, the ecological and genomic diversity of the Oryza genus, and the stress tolerance variation observed for wild Oryza species, including the genetic basis underlying the tolerance mechanisms found. The summary provided here is important to indicate how we should move forward to unlock the full potential of these germplasms for rice improvement.

  15. Survey of the transcriptome of Aspergillus oryzae via massively parallel mRNA sequencing.

    Science.gov (United States)

    Wang, Bin; Guo, Guangwu; Wang, Chao; Lin, Ying; Wang, Xiaoning; Zhao, Mouming; Guo, Yong; He, Minghui; Zhang, Yong; Pan, Li

    2010-08-01

    Aspergillus oryzae, an important filamentous fungus used in food fermentation and the enzyme industry, has been shown through genome sequencing and various other tools to have prominent features in its genomic composition. However, the functional complexity of the A. oryzae transcriptome has not yet been fully elucidated. Here, we applied direct high-throughput paired-end RNA-sequencing (RNA-Seq) to the transcriptome of A. oryzae under four different culture conditions. With the high resolution and sensitivity afforded by RNA-Seq, we were able to identify a substantial number of novel transcripts, new exons, untranslated regions, alternative upstream initiation codons and upstream open reading frames, which provide remarkable insight into the A. oryzae transcriptome. We were also able to assess the alternative mRNA isoforms in A. oryzae and found a large number of genes undergoing alternative splicing. Many genes and pathways that might be involved in higher levels of protein production in solid-state culture than in liquid culture were identified by comparing gene expression levels between different cultures. Our analysis indicated that the transcriptome of A. oryzae is much more complex than previously anticipated, and these results may provide a blueprint for further study of the A. oryzae transcriptome.

  16. An extra early mutant of pigeonpea

    International Nuclear Information System (INIS)

    Ravikesavan, R.; Kalaimagal, T.; Rathnaswamy, R.

    2001-01-01

    The redgram (Cajanus cajan (L.) Huth) variety 'Prabhat DT' was gamma irradiated with 100, 200, 300 and 400 Gy doses. Several mutants have been identified viz., extra early mutants, monostem mutants, obcordifoliate mutants and bi-stigmatic mutants. The extra early mutant was obtained when treated with 100 Gy dose. The mutant was selfed and forwarded from M 2 to M 4 generation. In the M 4 generation the mutant line was raised along with the parental variety. Normal cultural practices were followed and the biometrical observations were recorded. It was observed that for the characters viz., total number of branches per plant, number of pods per plants, seeds per pod, 100 seed weight and seed yield per plant there was no difference between the mutant and parent variety. Whereas, regarding the days to flowering and maturity the mutants were earlier than the parents. The observation was recorded from two hundred plants each. The mutant gives the same yield in 90 days as that of the parent variety in 107 days, which make it an economic mutant

  17. Problem-Solving Test: Tryptophan Operon Mutants

    Science.gov (United States)

    Szeberenyi, Jozsef

    2010-01-01

    This paper presents a problem-solving test that deals with the regulation of the "trp" operon of "Escherichia coli." Two mutants of this operon are described: in mutant A, the operator region of the operon carries a point mutation so that it is unable to carry out its function; mutant B expresses a "trp" repressor protein unable to bind…

  18. Rhizopus stolonifer exhibits dimorphism

    African Journals Online (AJOL)

    User

    2011-05-16

    May 16, 2011 ... C. O. Omoifo. Department of ... stolonifer could utilize glucose for growth, this study examined the effect ... H54Ar meter balance and added to the beaker. The pH was .... This work was done at the MTCC-1, Institute of Microbial. Technology ... Mucor circinelloides life cycle by on-line image analysis. J. Appl.

  19. Plant growth enhancing effects by a siderophore-producing endophytic streptomycete isolated from a Thai jasmine rice plant (Oryza sativa L. cv. KDML105).

    Science.gov (United States)

    Rungin, Siriwan; Indananda, Chantra; Suttiviriya, Pavinee; Kruasuwan, Worarat; Jaemsaeng, Ratchaniwan; Thamchaipenet, Arinthip

    2012-10-01

    An endophytic Streptomyces sp. GMKU 3100 isolated from roots of a Thai jasmine rice plant (Oryza sativa L. cv. KDML105) showed the highest siderophore production on CAS agar while phosphate solubilization and IAA production were not detected. A mutant of Streptomyces sp. GMKU 3100 deficient in just one of the plant growth promoting traits, siderophore production, was generated by inactivation of a desD-like gene encoding a key enzyme controlling the final step of siderophore biosynthesis. Pot culture experiments revealed that rice and mungbean plants inoculated with the wild type gave the best enhancement of plant growth and significantly increased root and shoot biomass and lengths compared with untreated controls and siderophore-deficient mutant treatments. Application of the wild type in the presence or absence of ferric citrate significantly promoted plant growth of both plants. The siderophore-deficient mutant clearly showed the effect of this important trait involved in plant-microbe interaction in enhancement of growth in rice and mungbean plants supplied with sequestered iron. Our results highlight the value of a substantial understanding of the relationship of the plant growth promoting properties of endophytic actinomycetes to the plants. Endophytic actinomycetes, therefore, can be applied as potentially safe and environmentally friendly biofertilizers in agriculture.

  20. Improvement of Aspergillus oryzae NRRL 3484 by mutagenesis and optimization of culture conditions in solid-state fermentation for the hyper-production of extracellular cellulase.

    Science.gov (United States)

    El-Ghonemy, Dina Helmy; Ali, Thanaa Hamed; El-Bondkly, Ahmed Mohamed; Moharam, Maysa El-Sayed; Talkhan, Fatma Nabeeh

    2014-11-01

    Spore suspensions of Aspergillus oryzae NRRL 3484 were subjected to mutagenesis using ultraviolet-irradiation followed by chemical treatments to improve the biosynthesis of cellulase. Ten mutant strains namely UEAC7, UEAR5, UNAC4, UNAC16, UNAR19, UNBC7, UNBR3, UNBR10, UNBR23 and UNBR25 were selected and their extracellular cellulase activities were assayed. Mutant UNAC4 gave the highest cellulase production [2,455 ± 28 U/g-dry substrate (ds) for filter paper-ase (FP-ase)] in a yield 4-fold exceeding that of the wild type strain (578 ± 5.0 U/g-ds for FP-ase). Rice straw (RS) was used as a sole carbon source for the enzyme production at a concentration of 10 % (w/v). Maximum cellulase production was achieved at initial medium pH 5.5, initial moisture content 77 % and an incubation temperature 28 °C on the fifth day of growth. NH4Cl proved to be the suitable added nitrogen source for maximum enzyme production followed by peptone. These results clearly indicate the cost-effectiveness of solid state fermentation technology in the economic production of extracellular cellulase. The hyper-production of cellulase by mutant strain UNAC4 has potential for industrial processes that convert lignocellulosic material (e.g. RS) into products of commercial value such as glucose and biofuels.

  1. Detection of Alien Oryza punctata Kotschy Chromosomes in Rice, Oryza sativa L., by Genomic in situ Hybridization

    OpenAIRE

    Yasui, Hideshi; Nonomura, Ken-ichi; Iwata, Nobuo; 安井, 秀; 野々村, 賢一; 岩田, 伸夫

    1997-01-01

    Genomic in situ hybridization (GIS H) using total Oryza punctata Kotschy genomic DNA as a probe was applied to detect alien chromosomes transferred from O. punctata (W1514: 2n=2x=24: BB) to O. sativa Japonica cultivar, Nipponbare (2n=2x=24: AA). Only 12 chromosomes in the interspecific hybrids (2n=3x=36: AAB) between autotetraploid of O. sativa cultivar Nipponbare and a diploid strain of O. punctata (W1514) showed intense staining by FITC in mitotic metaphase spreads. Only one homologous pair...

  2. Peran Direct Fed Microbials (DFM Saccharomyces cerevisiae dan Aspergillus oryzae terhadap Produktivitas Ternak Ruminansia : Review

    Directory of Open Access Journals (Sweden)

    H. Suryani

    2015-02-01

    Full Text Available Mikroorganisme yang biasa digunakan dalam pakan ternak ruminansia biasanya berupa probiotik. Probiotik memiliki makna yang bersepadanan dengan Direct Fed Microbials (DFM. Penambahan DFM jenis Saccharomyces cerevisiae dan Aspergillus oryzae pada pakan ternak ruminansia mampu memanipulasi rumen dengan meningkatkan populasi bakteri pemecah serat sehingga dapat meningkatkan kecernaan dan meningkatkan bobot badan. Mekanisme kerja S. cerevisiae dan A. oryzae yang masuk kedalam tubuh ternak dan mempengaruhi pencernaan atau penyerapan, ada yang sudah diketahui secara jelas tetapi ada juga yang masih berupa hipotesa. Pemanfaatan DFM jenis S. cerevisiae dan A. oryzae secara tunggal maupun kombinasi sebagian telah diamati dan memberikan respon positif.

  3. WRKY transcription factor genes in wild rice Oryza nivara.

    Science.gov (United States)

    Xu, Hengjian; Watanabe, Kenneth A; Zhang, Liyuan; Shen, Qingxi J

    2016-08-01

    The WRKY transcription factor family is one of the largest gene families involved in plant development and stress response. Although many WRKY genes have been studied in cultivated rice (Oryza sativa), the WRKY genes in the wild rice species Oryza nivara, the direct progenitor of O. sativa, have not been studied. O. nivara shows abundant genetic diversity and elite drought and disease resistance features. Herein, a total of 97 O. nivara WRKY (OnWRKY) genes were identified. RNA-sequencing demonstrates that OnWRKY genes were generally expressed at higher levels in the roots of 30-day-old plants. Bioinformatic analyses suggest that most of OnWRKY genes could be induced by salicylic acid, abscisic acid, and drought. Abundant potential MAPK phosphorylation sites in OnWRKYs suggest that activities of most OnWRKYs can be regulated by phosphorylation. Phylogenetic analyses of OnWRKYs support a novel hypothesis that ancient group IIc OnWRKYs were the original ancestors of only some group IIc and group III WRKYs. The analyses also offer strong support that group IIc OnWRKYs containing the HVE sequence in their zinc finger motifs were derived from group Ia WRKYs. This study provides a solid foundation for the study of the evolution and functions of WRKY genes in O. nivara. © The Author 2016. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

  4. Transcriptomics of the rice blast fungus Magnaporthe oryzae in response to the bacterial antagonist Lysobacter enzymogenes reveals candidate fungal defense response genes.

    Directory of Open Access Journals (Sweden)

    Sandra M Mathioni

    Full Text Available Plants and animals have evolved a first line of defense response to pathogens called innate or basal immunity. While basal defenses in these organisms are well studied, there is almost a complete lack of understanding of such systems in fungal species, and more specifically, how they are able to detect and mount a defense response upon pathogen attack. Hence, the goal of the present study was to understand how fungi respond to biotic stress by assessing the transcriptional profile of the rice blast pathogen, Magnaporthe oryzae, when challenged with the bacterial antagonist Lysobacter enzymogenes. Based on microscopic observations of interactions between M. oryzae and wild-type L. enzymogenes strain C3, we selected early and intermediate stages represented by time-points of 3 and 9 hours post-inoculation, respectively, to evaluate the fungal transcriptome using RNA-seq. For comparative purposes, we also challenged the fungus with L. enzymogenes mutant strain DCA, previously demonstrated to be devoid of antifungal activity. A comparison of transcriptional data from fungal interactions with the wild-type bacterial strain C3 and the mutant strain DCA revealed 463 fungal genes that were down-regulated during attack by C3; of these genes, 100 were also found to be up-regulated during the interaction with DCA. Functional categorization of genes in this suite included those with roles in carbohydrate metabolism, cellular transport and stress response. One gene in this suite belongs to the CFEM-domain class of fungal proteins. Another CFEM class protein called PTH11 has been previously characterized, and we found that a deletion in this gene caused advanced lesion development by C3 compared to its growth on the wild-type fungus. We discuss the characterization of this suite of 100 genes with respect to their role in the fungal defense response.

  5. Dwarf mutant of rice variety Seratus Malam

    International Nuclear Information System (INIS)

    Mugiono, P. S.; Soemanggono, A.M.R.

    1989-01-01

    Full text: Seeds of 'Seratus Malam', a local tall upland variety with long panicles and high yield potential were irradiated with 10-50 krad gamma rays in 1983. From 50,000 M 2 plants, 130 semidwarf mutants and 1 dwarf mutant were selected. The dwarf mutant M-362 was obtained from the 10 krad treatment. The mutant shows about 50% reduction in plant height, but also in number of productive tillers. Thus the yield per plant is also significantly less. However, the mutant gene is not allelic to DGWG and therefore may be useful in cross breeding. (author)

  6. Rhizopus-associated soft tissue infection in an immunocompetent air-conditioning technician after a road traffic accident: a case report and review of the literature.

    Science.gov (United States)

    Rabie, Nada B; Althaqafi, Abdulhakeem O

    2012-03-01

    Rhinocerebral or sinopulmonary mucromycosis is a well-recognized human fungal infection found among immunocompromised and diabetic patients. However, the infection is rare among immunocompetent hosts. We are reporting the case of an adult immunocompetent male patient working as an air-conditioning technician. The patient was a victim of a road traffic accident (RTA) and sustained multiple fractures in the proximal part of the left tibia, distal femur, and scapula. Two weeks postoperatively, Rhizopus microspores were isolated from an infected traumatic wound over the distal femur. Surgical debridement was performed, and the patient was started on amphotericin B. Occupational exposure history and workplace environmental sanitation are crucial for the prevention of this potentially fatal yet preventable infection. Copyright © 2011 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

  7. Comparative Transcriptome Profiling of Rice Near-Isogenic Line Carrying Xa23 under Infection of Xanthomonas oryzae pv. oryzae.

    Science.gov (United States)

    Tariq, Rezwan; Wang, Chunlian; Qin, Tengfei; Xu, Feifei; Tang, Yongchao; Gao, Ying; Ji, Zhiyuan; Zhao, Kaijun

    2018-03-02

    Bacterial blight, caused by Xanthomonas oryzae pv. oryzae ( Xoo ), is an overwhelming disease in rice-growing regions worldwide. Our previous studies revealed that the executor R gene Xa23 confers broad-spectrum disease resistance to all naturally occurring biotypes of Xoo . In this study, comparative transcriptomic profiling of two near-isogenic lines (NILs), CBB23 (harboring Xa23 ) and JG30 (without Xa23 ), before and after infection of the Xoo strain, PXO99 A , was done by RNA sequencing, to identify genes associated with the resistance. After high throughput sequencing, 1645 differentially expressed genes (DEGs) were identified between CBB23 and JG30 at different time points. Gene Ontlogy (GO) analysis categorized the DEGs into biological process, molecular function, and cellular component. KEGG analysis categorized the DEGs into different pathways, and phenylpropanoid biosynthesis was the most prominent pathway, followed by biosynthesis of plant hormones, flavonoid biosynthesis, and glycolysis/gluconeogenesis. Further analysis led to the identification of differentially expressed transcription factors (TFs) and different kinase responsive genes in CBB23, than that in JG30. Besides TFs and kinase responsive genes, DEGs related to ethylene, jasmonic acid, and secondary metabolites were also identified in both genotypes after PXO99 A infection. The data of DEGs are a precious resource for further clarifying the network of Xa23 -mediated resistance.

  8. Asexual reproduction induces a rapid and permanent loss of sexual reproduction capacity in the rice fungal pathogen Magnaporthe oryzae: results of in vitro experimental evolution assays

    Directory of Open Access Journals (Sweden)

    Saleh Dounia

    2012-03-01

    Full Text Available Abstract Background Sexual reproduction is common in eukaryotic microorganisms, with few species reproducing exclusively asexually. However, in some organisms, such as fungi, asexual reproduction alternates with episodic sexual reproduction events. Fungi are thus appropriate organisms for studies of the reasons for the selection of sexuality or clonality and of the mechanisms underlying this selection. Magnaporthe oryzae, an Ascomycete causing blast disease on rice, reproduces mostly asexually in natura. Sexual reproduction is possible in vitro and requires (i two strains of opposite mating types including (ii at least one female-fertile strain (i.e. a strain able to produce perithecia, the female organs in which meiosis occurs. Female-fertile strains are found only in limited areas of Asia, in which evidence for contemporary recombination has recently been obtained. We induced the forced evolution of four Chinese female-fertile strains in vitro by the weekly transfer of asexual spores (conidia between Petri dishes. We aimed to determine whether female fertility was rapidly lost in the absence of sexual reproduction and whether this loss was controlled genetically or epigenetically. Results All the strains became female-sterile after 10 to 19 rounds of selection under asexual conditions. As no single-spore isolation was carried out, the observed decrease in the production of perithecia reflected the emergence and the invasion of female-sterile mutants. The female-sterile phenotype segregated in the offspring of crosses between female-sterile evolved strains and female-fertile wild-type strains. This segregation was maintained in the second generation in backcrosses. Female-sterile evolved strains were subjected to several stresses, but none induced the restoration of female fertility. This loss of fertility was therefore probably due to genetic rather than epigenetic mechanisms. In competition experiments, female-sterile mutants produced similar

  9. Ectopic expression of a vesicle trafficking gene, OsRab7, from Oryza ...

    African Journals Online (AJOL)

    Jane

    2011-07-18

    Jul 18, 2011 ... OsRab7, from Oryza sativa, confers tolerance to several ... Key Laboratory of Molecular Biology and Gene Engineering, College of Life Science, Nanchang University, ... The reverse transcription was performed using MMLV.

  10. Growth responses of NaCl stressed rice (Oryza sativa L.) plants ...

    African Journals Online (AJOL)

    GREGORY

    2010-09-27

    Sep 27, 2010 ... 3Department of Statistics, University of Sindh Jamshoro, Pakistan. 4Mityari Sugar Mills ... Key words: Oryza sativa L., seedling biomass, epidermal cells, proline content. ... Attempts to reduce the soil salinity, using mechanical.

  11. Construction and application of a novel genetically engineered Aspergillus oryzae for expressing proteases

    Directory of Open Access Journals (Sweden)

    Xiao-Chun Yu

    2017-09-01

    Conclusions: These findings suggest that cloning of microbial protease genes with good physicochemical properties and expressing them in an ideal host such as A. oryzae is a novel strategy to enhance the value of soybean meal.

  12. Recombinant expression and purification of an Oxysterol Binding Protein from Aspergillus oryzae 3.042

    Directory of Open Access Journals (Sweden)

    Zhang Xian

    2017-01-01

    Full Text Available A full-length cDNA encoding a candidate Oxysterol-binding protein(OSBP from Aspergillus oryzae (AoOSBP was cloned and expressed in Escherichia coli as a maltose-binding protein (MBP fusion protein. The MBP-AoOSBP protein from the importantly industrial fungus A. oryzae was purified by amylose resin and chromatography column. SDS-PAGE showed that MBP-AoOSBP has an estimated molecular weight of 182 kDa. OSBP and its homologues (ORPs own the affinity for oxysterols, cholesterol and glycerophospholipids. According to the superiority of A. oryzae in the fermented foods and also in food-grade productions pharmaceutical enzyme manufacture, it is meaningful to identify the biochemical properties of OSBP in A. oryzae.

  13. Effect of yeast culture and Aspergillus oryzae fermentation extract on ruminal characteristics and nutrient digestibility.

    Science.gov (United States)

    Wiedmeier, R D; Arambel, M J; Walters, J L

    1987-10-01

    Four nonpregnant and nonlactating Holstein cows fitted with ruminal fistulas were assigned to each of four diets in a 4 X 4 Latin square design. Dietary treatments were 1) basal diet containing 50% concentrate; 2) basal diet plus 90 g/d yeast culture; 3) basal diet plus 2.63 g/d Aspergillus oryzae fermentation extract; 4) basal diet plus 90 g/d of A. oryzae fermentation extract and yeast culture. Cows were fed diets at a rate of 86 g DM/kg BW.75 for 14 d adaptation followed by an 8-d collection period. Digestibility of dry matter was increased by A. oryzae and A. oryzae and yeast culture combination treatments. Digestibility of CP was increased regardless of fungal culture addition. Hemicellulose digestibility, percent ruminal cellulolytic organisms, and acetate to propionate ratio were increased by the addition of fungal supplements.

  14. PNRI mutant variety: Cordyline 'Afable'

    International Nuclear Information System (INIS)

    Aurigue, Fernando B.

    2012-01-01

    Cordyline 'Afable', registered by the Philippine Nuclear Research Institute as NSIC 2009 Or-83, is an induced mutant developed from Cordyline 'Kiwi' by treating stem cuttings with acute gamma radiation from a Cobalt-60 source. The new mutant is identical to Cordyline 'Kiwi' in growth habit but differs in foliage color, and exhibits field resistance to Phytophthora sp., a fungus that causes leaf blight and rot in Ti plants. Results of this mutation breeding experiment showed that leaf color was altered by gamma irradiation and resistance to fungal diseases was improved. It also demonstrated how mutations that occur in nature may be generated artificially. Propagation of cordyline 'Afable' is true-to-type by vegetative propagation methods, such as separation of suckers and offshoots, shoot tip cutting, and top cutting. Aside from landscaping material, terrarium or dish-garden plant, it is ideal as containerized plant for indoor and outdoor use. The leaves or shoots may be harvested as cut foliage for flower arrangements. (author)

  15. Isolation and identification of fungi responsible for leaf spots disease ...

    African Journals Online (AJOL)

    The diseased plant leaves were taken to the laboratory for culture, isolation, and ... These included; Alternaria longipes, Aspergillus fumigatus, Aspergillus niger, ... Phomopsis mangiferae, Pseudofusicoccum spp. and Rhizopus oryzae.

  16. Gamma ray induced mutants in Coleus

    International Nuclear Information System (INIS)

    Vasudevan, K.; Jos, J.S.

    1988-01-01

    The germplasm collection of Chinese potato (Coleus parviflorus Benth) contains almost no variation for yield contributing traits. The crop does not produce seeds. Treatment of underground tubers with 1 kR, 2 kR, 3 kR and 4 kR gamma rays resulted in 50 morphologically different mutants which are maintained as mutant clones. In the M 1 V 1 generation, suspected mutant sprouts, were carefully removed and grown separately. The most interesting mutant types are the following: (i) erect mutant with spoon shaped light green leaves, 30 cm long inflorescences against 20 cm in the control, cylindrical tubers measuring ca. 7.0 cm long and 3 cm girth against 4 cm and 2.5 cm in the control (ii) early mutants 1 and 2, one having less leaf serration, the other having light green small leaves and dwarf type (iii) fleshy leaf mutant, dark green, thick and smooth leaves. Control plants spread almost in 1 m 2 area and bear tubers from the nodes of branches. In the early mutants tuber formation is mainly restricted to the base of the plant, which makes harvest easier. The crop usually matures within 150 - 160 days, the early mutants are ready for harvest 100 days after planting. As the mutants are less spreading, the yield could be increased by closer spacing

  17. Gamma ray induced mutants in Coleus

    Energy Technology Data Exchange (ETDEWEB)

    Vasudevan, K; Jos, J S [Central Tuber Crops Research Institute, Trivandrum, Kerala (India)

    1988-07-01

    The germplasm collection of Chinese potato (Coleus parviflorus Benth) contains almost no variation for yield contributing traits. The crop does not produce seeds. Treatment of underground tubers with 1 kR, 2 kR, 3 kR and 4 kR gamma rays resulted in 50 morphologically different mutants which are maintained as mutant clones. In the M{sub 1}V{sub 1} generation, suspected mutant sprouts, were carefully removed and grown separately. The most interesting mutant types are the following: (i) erect mutant with spoon shaped light green leaves, 30 cm long inflorescences against 20 cm in the control, cylindrical tubers measuring ca. 7.0 cm long and 3 cm girth against 4 cm and 2.5 cm in the control (ii) early mutants 1 and 2, one having less leaf serration, the other having light green small leaves and dwarf type (iii) fleshy leaf mutant, dark green, thick and smooth leaves. Control plants spread almost in 1 m{sup 2} area and bear tubers from the nodes of branches. In the early mutants tuber formation is mainly restricted to the base of the plant, which makes harvest easier. The crop usually matures within 150 - 160 days, the early mutants are ready for harvest 100 days after planting. As the mutants are less spreading, the yield could be increased by closer spacing.

  18. The chemical heritage of Aspergillus flavus in A. oryzae RIB 40

    OpenAIRE

    Rank, Christian; Klejnstrup, Marie Louise; Petersen, Lene Maj; Frisvad, Jens Christian; Larsen, Thomas Ostenfeld

    2011-01-01

    Aspergillus oryzae is a very important species in biotechnology and has been used for centuries in traditional Asian fermentation. The RIB40 strain is particularly interesting as it was one of the first genome sequenced Aspergilli together with A. flavus, a prominent food and feed contaminant capable of producing aflatoxin. These species can be perceived as ecotypes. We have analyzed A. oryzae RIB40 and found that the chemical potential could be enhanced significantly under certain conditions...

  19. Comparative Chemistry of Aspergillus oryzae (RIB40) and A. flavus (NRRL 3357)

    OpenAIRE

    Rank, Christian; Klejnstrup, Marie Louise; Petersen, Lene Maj; Kildgaard, Sara; Frisvad, Jens Christian; Gotfredsen, Charlotte Held; Larsen, Thomas Ostenfeld

    2012-01-01

    Aspergillus oryzae and A. flavus are important species in industrial biotechnology and food safety and have been some of the first aspergilli to be fully genome sequenced. Bioinformatic analysis has revealed 99.5% gene homology between the two species pointing towards a large coherence in the secondary metabolite production. In this study we report on the first comparison of secondary metabolite production between the full genome sequenced strains of A. oryzae (RIB40) and A. flavus (NRRL 3357...

  20. Sharing mutants and experimental information prepublication using FgMutantDb (https://scabusa.org/FgMutantDb).

    Science.gov (United States)

    Baldwin, Thomas T; Basenko, Evelina; Harb, Omar; Brown, Neil A; Urban, Martin; Hammond-Kosack, Kim E; Bregitzer, Phil P

    2018-06-01

    There is no comprehensive storage for generated mutants of Fusarium graminearum or data associated with these mutants. Instead, researchers relied on several independent and non-integrated databases. FgMutantDb was designed as a simple spreadsheet that is accessible globally on the web that will function as a centralized source of information on F. graminearum mutants. FgMutantDb aids in the maintenance and sharing of mutants within a research community. It will serve also as a platform for disseminating prepublication results as well as negative results that often go unreported. Additionally, the highly curated information on mutants in FgMutantDb will be shared with other databases (FungiDB, Ensembl, PhytoPath, and PHI-base) through updating reports. Here we describe the creation and potential usefulness of FgMutantDb to the F. graminearum research community, and provide a tutorial on its use. This type of database could be easily emulated for other fungal species. Published by Elsevier Inc.

  1. Development of enzyme technology for Aspergillus oryzae, A. sojae, and A. luchuensis, the national microorganisms of Japan.

    Science.gov (United States)

    Ichishima, Eiji

    2016-09-01

    This paper describes the modern enzymology in Japanese bioindustries. The invention of Takadiastase by Jokiti Takamine in 1894 has revolutionized the world of industrial enzyme production by fermentation. In 1949, a new γ-amylase (glucan 1,4-α-glucosidase, EC 3.2.1.3) from A. luchuensis (formerly designated as A. awamori), was found by Kitahara. RNase T1 (guanyloribonuclease, EC 3.1.27.3) was discovered by Sato and Egami. Ando discovered Aspergillus nuclease S1 (single-stranded nucleate endonuclease, EC 3.1.30.1). Aspergillopepsin I (EC 3.4.23.18) from A. tubingensis (formerly designated as A. saitoi) activates trypsinogen to trypsin. Shintani et al. demonstrated Asp76 of aspergillopepsin I as the binding site for the basic substrate, trypsinogen. The new oligosaccharide moieties Man10GlcNAc2 and Man11GlcNAc2 were identified with α-1,2-mannosidase (EC 3.2.1.113) from A. tubingensis. A yeast mutant compatible of producing Man5GlcNAc2 human compatible sugar chains on glycoproteins was constructed. The acid activation of protyrosinase from A. oryzae at pH 3.0 was resolved. The hyper-protein production system of glucoamylase was established in a submerged culture.

  2. PENGUJIAN BEBERAPA JENIS INSEKTISIDA NABATI TERHADAP KUTU BERAS (Sitophilus oryzae L

    Directory of Open Access Journals (Sweden)

    Muhammad Isnaini

    2015-08-01

    Full Text Available The purpose of this study first to determine whether or not capable of  natural insecticides to kill Sitophilus oryzae L and to determine effective of  natural insecticides to kill Sitophilus oryzae L. This type of research is an experimental research with quantitative descriptive and The data collection techniques used is the observation and documentation. The data analyzed with ANOVA analysis techniques followed by BJND test. Based on the comparison of the calculated F value contained in the ANOVA analysis is greater than the F table , either at the significant level of 5 % and the 1% significance level (79.57 > 2.67 / 4:43. Thus stated that H1 accepted and rejected H0. The results showed that the first, the natural insecticide able to kill Sitophilus oryzae L and mortality rate highest in Cymbopogon citratus treatment that is equal to 13.2 with the total percentage of mortality of 66%, both effective plant-based insecticides to kill Sitophilus oryzae L that leaves just Cymbopogon citratus (66% and Morinda citrifolia L (60%.The conclusions obtained from this study: First, some kind of  natural insecticide able to kill Sitophilus oryzae L,  second based on the results of the ANOVA analysis of all types of insecticides to kill Sitophilus oryzae L effectively, but if effectiveness was seen by the number of mortality up to 50 % or more, then just Cymbopogon citratus and Morinda citrifolia L.

  3. Aspergillus oryzae-based cell factory for direct kojic acid production from cellulose.

    Science.gov (United States)

    Yamada, Ryosuke; Yoshie, Toshihide; Wakai, Satoshi; Asai-Nakashima, Nanami; Okazaki, Fumiyoshi; Ogino, Chiaki; Hisada, Hiromoto; Tsutsumi, Hiroko; Hata, Yoji; Kondo, Akihiko

    2014-05-18

    Kojic acid (5-Hydroxy-2-(hydroxymethyl)-4-pyrone) is one of the major secondary metabolites in Aspergillus oryzae. It is widely used in food, pharmaceuticals, and cosmetics. The production cost, however, is too high for its use in many applications. Thus, an efficient and cost-effective kojic acid production process would be valuable. However, little is known about the complete set of genes for kojic acid production. Currently, kojic acid is produced from glucose. The efficient production of kojic acid using cellulose as an inexpensive substrate would help establish cost-effective kojic acid production. A kojic acid transcription factor gene over-expressing the A. oryzae strain was constructed. Three genes related to kojic acid production in this strain were transcribed in higher amounts than those found in the wild-type strain. This strain produced 26.4 g/L kojic acid from 80 g/L glucose. Furthermore, this strain was transformed with plasmid harboring 3 cellulase genes. The resultant A. oryzae strain successfully produced 0.18 g/L of kojic acid in 6 days of fermentation from the phosphoric acid swollen cellulose. Kojic acid was produced directly from cellulose material using genetically engineered A. oryzae. Because A. oryzae has efficient protein secretion ability and secondary metabolite productivity, an A. oryzae-based cell factory could be a platform for the production of various kinds of bio-based chemicals.

  4. Genomics of Aspergillus oryzae: Learning from the History of Koji Mold and Exploration of Its Future

    Science.gov (United States)

    Machida, Masayuki; Yamada, Osamu; Gomi, Katsuya

    2008-01-01

    At a time when the notion of microorganisms did not exist, our ancestors empirically established methods for the production of various fermentation foods: miso (bean curd seasoning) and shoyu (soy sauce), both of which have been widely used and are essential for Japanese cooking, and sake, a magical alcoholic drink consumed at a variety of ritual occasions, are typical examples. A filamentous fungus, Aspergillus oryzae, is the key organism in the production of all these traditional foods, and its solid-state cultivation (SSC) has been confirmed to be the secret for the high productivity of secretory hydrolases vital for the fermentation process. Indeed, our genome comparison and transcriptome analysis uncovered mechanisms for effective degradation of raw materials in SSC: the extracellular hydrolase genes that have been found only in the A. oryzae genome but not in A. fumigatus are highly induced during SSC but not in liquid cultivation. Also, the temperature reduction process empirically adopted in the traditional soy-sauce fermentation processes has been found to be important to keep strong expression of the A. oryzae-specific extracellular hydrolases. One of the prominent potentials of A. oryzae is that it has been successfully applied to effective degradation of biodegradable plastic. Both cutinase, responsible for the degradation of plastic, and hydrophobin, which recruits cutinase on the hydrophobic surface to enhance degradation, have been discovered in A. oryzae. Genomic analysis in concert with traditional knowledge and technology will continue to be powerful tools in the future exploration of A. oryzae. PMID:18820080

  5. Aflatoxin B1 Detoxification by Aspergillus oryzae from Meju, a Traditional Korean Fermented Soybean Starter.

    Science.gov (United States)

    Lee, Kyu Ri; Yang, Sun Min; Cho, Sung Min; Kim, Myunghee; Hong, Sung-Yong; Chung, Soo Hyun

    2016-11-04

    Aflatoxins are classified as Group 1 (carcinogenic to humans) by the International Agency for Research on Cancer (IARC). In this study, a total of 134 fungal strains were isolated from 65 meju samples, and two fungal isolates were selected as potential aflatoxin B₁ (AFB₁)-biodetoxification fungi. These fungi were identified as Aspergillus oryzae MAO103 and A. oryzae MAO104 by sequencing the beta-tubulin gene. The two A. oryzae strains were able to degrade more than 90% of AFB1 (initial concentration: 40 µg/L) in a culture broth in 14 days. The mutagenic effects of AFB₁ treated with A. oryzae MAO103 and MAO104 significantly decreased to 5.7% and 6.4%, respectively, in the frame-shift mutation of Ames tests using Salmonella typhimurium TA 98. The base-substituting mutagenicity of AFB₁ was also decreased by the two fungi. Moreover, AFB1 production by A. flavus was significantly decreased by the two A. oryzae strains on soybean-based agar plates. Our data suggest that the two AFB1-detoxification A. oryzae strains have potential application to control AFB₁ in foods and feeds.

  6. The whole chloroplast genome of wild rice (Oryza australiensis).

    Science.gov (United States)

    Wu, Zhiqiang; Ge, Song

    2016-01-01

    The whole chloroplast genome of wild rice (Oryza australiensis) is characterized in this study. The genome size is 135,224  bp, exhibiting a typical circular structure including a pair of 25,776  bp inverted repeats (IRa,b) separated by a large single-copy region (LSC) of 82,212  bp and a small single-copy region (SSC) of 12,470  bp. The overall GC content of the genome is 38.95%. 110 unique genes were annotated, including 76 protein-coding genes, 4 ribosomal RNA genes, and 30t RNA genes. Among these, 18 are duplicated in the inverted repeat regions, 13 genes contain one intron, and 2 genes (rps12 and ycf3) have two introns.

  7. Oxygen dynamics in submerged rice (Oryza sativa L.)

    DEFF Research Database (Denmark)

    Colmer, Timothy D.; Pedersen, Ole

    2008-01-01

    Complete submergence of plants prevents direct O2 and CO2 exchange with air. Underwater photosynthesis can result in marked diurnal changes in O2 supply to submerged plants. Dynamics in pO2 had not been measured directly for submerged rice (Oryza sativa), but in an earlier study, radial O2 loss...... from roots showed an initial peak following shoot illumination.  O2 dynamics in shoots and roots of submerged rice were monitored during light and dark periods, using O2 microelectrodes. Tissue sugar concentrations were also measured.  On illumination of shoots of submerged rice, pO2 increased rapidly...... of magnitude higher than in darkness, enhancing also pO2 in roots.The initial peak in pO2 following illumination of submerged rice was likely to result from high initial rates of net photosynthesis, fuelled by CO2 accumulated during the dark period. Nevertheless, since sugars decline with time in submerged...

  8. Expression and Activity Analysis of Fructosyltransferase from Aspergillus oryzae.

    Science.gov (United States)

    Guan, Lihong; Chen, Liping; Chen, Yongsen; Zhang, Nu; Han, Yawei

    2017-08-01

    The fructosyltransferase gene was isolated and cloned from Aspergillus oryzae. The gene was 1368 bp, which encoded a protein of 455 amino acids. To analyze the activity of the expressed fructosyltransferase, the pET32a-fructosyltransferase recombined plasmid was transformed into Escherichia coli BL21. The fructosyltransferase gene was successfully expressed by Isopropyl-β-d-thiogalactoside (IPTG) induction. The molecular weight of the expression protein was about 45 kDa. The optimal conditions of protein expression were 25 °C, 0.1 mM IPTG, and 8 h of inducing time. The optimal concentration of urea dealing with inclusion body was 2.5 M. The expressed protein exhibited a strong fructosyl transfer activity. These results showed that the expressed fructosyltransferas owned transferase activity, and could catalyze the synthesis of sucrose-6-acetate.

  9. Cloning and characterization of two flavohemoglobins from Aspergillus oryzae

    International Nuclear Information System (INIS)

    Zhou Shengmin; Fushinobu, Shinya; Nakanishi, Yoshito; Kim, Sang-Wan; Wakagi, Takayoshi; Shoun, Hirofumi

    2009-01-01

    Two flavohemoglobin (FHb) genes, fhb1 and fhb2, were cloned from Aspergillus oryzae. The amino acid sequences of the deduced FHb1 and FHb2 showed high identity to other FHbs except for the predicted mitochondrial targeting signal in the N-terminus of FHb2. The recombinant proteins displayed absorption spectra similar to those of other FHbs. FHb1 and FHb2 were estimated to be a monomer and a dimer in solution, respectively. Both of the isozymes exhibit high NO dioxygenase (NOD) activity. FHb1 utilizes either NADH or NADPH as an electron donor, whereas FHb2 can only use NADH. These results suggest that FHb1 and FHb2 are fungal counterparts of bacterial FHbs and act as NO detoxification enzymes in the cytosol and mitochondria, respectively. This study is the first to show that a microorganism contains two isozymes of FHb and that intracellular localization of the isozymes could differ.

  10. Cultivation characteristics of immobilized Aspergillus oryzae for kojic acid production.

    Science.gov (United States)

    Kwak, M Y; Rhee, J S

    1992-04-15

    Aspergillus oryzae in situ grown from spores entrapped in calcium alginate gel beads was used for the production of kojic acid. The immobilized cells in flask cultures produced kojic acid in a linear proportion while maintaining the stable metabolic activity for a prolonged production period. Kojic acid was accumulated up to a high concentration of 83 g/L, at which the kojic acid began to crystallize, and, thus, the culture had to be replaced with fresh media for the next batch culture. The overall productivities of two consecutive cultivations were higher than that of free mycelial fermentation. However, the production rate of kojic acid by the immobilized cells was suddenly decreased with the appearance of central cavernae inside the immobilized gel beads after 12 days of the third batch cultivation.

  11. Drimane sesquiterpenoids from the Aspergillus oryzae QXPC-4.

    Science.gov (United States)

    Ren, Ren; Chen, Chao-Jun; Hu, Sha-Sha; Ge, Hui-Ming; Zhu, Wen-Yong; Tan, Ren-Xiang; Jiao, Rui-Hua

    2015-03-01

    Three new drimane sesquiterpenoids, astellolides C-E (1-3, resp.), four new drimane sesquiterpenoid p-hydroxybenzoates, astellolides F-I (4-7, resp.), together with two known compounds astellolides A and B (8 and 9, resp.), have been isolated from the liquid culture of Aspergillus oryzae (strain No. QXPC-4). Their structures were established by comprehensive analysis of spectroscopic data. The relative and absolute configurations were determined on the basis of NOESY and CD data, together with single-crystal X-ray diffraction analyses of compounds 1-3. The metabolites were evaluated for their cytotoxic activities, however, no compounds showed a significant cytotoxicity against the tested cell lines at a concentration of 20 μM. Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.

  12. Evaluation of commercial soy sauce koji strains of Aspergillus oryzae for γ-aminobutyric acid (GABA) production.

    Science.gov (United States)

    Ab Kadir, Safuan; Wan-Mohtar, Wan Abd Al Qadr Imad; Mohammad, Rosfarizan; Abdul Halim Lim, Sarina; Sabo Mohammed, Abdulkarim; Saari, Nazamid

    2016-10-01

    In this study, four selected commercial strains of Aspergillus oryzae were collected from soy sauce koji. These A. oryzae strains designated as NSK, NSZ, NSJ and NST shared similar morphological characteristics with the reference strain (A. oryzae FRR 1675) which confirmed them as A. oryzae species. They were further evaluated for their ability to produce γ-aminobutyric acid (GABA) by cultivating the spore suspension in a broth medium containing 0.4 % (w/v) of glutamic acid as a substrate for GABA production. The results showed that these strains were capable of producing GABA; however, the concentrations differed significantly (P sauce production.

  13. Studies on reduced height mutants in rice

    International Nuclear Information System (INIS)

    Narahari, P.; Bhagwat, S.G.

    1984-01-01

    Two cross-bred derivatives of the mutant TR5xTR17 and TR21 continued to show promise and were advanced to wider scale testing. TR5 was found to carry a semi-dwarfing gene different from that in IR8. New semi-dwarf mutants were screened from M 2 through M 4 from two separate radiation experiments. The gibberellin response of seedlings of mutant and tester strains was evaluated and crosses of tester stocks and mutant semi-dwarfs were made for genetic analyses. (author)

  14. Comparative proteomic analyses reveal that the regulators of G-protein signaling proteins regulate amino acid metabolism of the rice blast fungus Magnaporthe oryzae.

    Science.gov (United States)

    Zhang, Haifeng; Ma, Hongyu; Xie, Xin; Ji, Jun; Dong, Yanhan; Du, Yan; Tang, Wei; Zheng, Xiaobo; Wang, Ping; Zhang, Zhengguang

    2014-11-01

    The rice blast fungus Magnaporthe oryzae encodes eight regulators of G-protein (GTP-binding protein) signaling (RGS) proteins MoRgs1-MoRgs8 that orchestrate the growth, asexual/sexual production, appressorium differentiation, and pathogenicity. To address the mechanisms by which MoRgs proteins function, we conducted a 2DE proteome study and identified 82 differentially expressed proteins by comparing five ∆Morgs mutants with wild-type Guy11 strain. We found that the abundances of eight amino acid (AA) biosynthesis or degradation associated proteins were markedly altered in five ∆Morgs mutants, indicating one of the main collective roles for the MoRgs proteins is to influence AA metabolism. We showed that MoRgs proteins have distinct roles in AA metabolism and nutrient responses from growth assays. In addition, we characterized MoLys20 (Lys is lysine), a homocitrate synthase, whose abundance was significantly decreased in the ∆Morgs mutants. The ∆Molys20 mutant is auxotrophic for lys and exogenous lys could partially rescue its auxotrophic defects. Deletion of MoLYS20 resulted in defects in conidiation and infection, as well as pathogenicity on rice. Overall, our results indicate that one of the critical roles for MoRgs proteins is to regulate AA metabolism, and that MoLys20 may be directly or indirectly regulated by MoRgs and participated in lys biosynthesis, thereby affecting fungal development and pathogenicity. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Low-energy N-ion beam biotechnology application in the induction of Thai jasmine rice mutant with improved seed storability

    Science.gov (United States)

    Semsang, Nuananong; Techarang, Jiranat; Yu, Liangdeng; Phanchaisri, Boonrak

    2018-06-01

    Low-energy heavy-ion beam is a novel biotechnology used for mutation induction in plants. We used a low-energy N-ion beam to induce mutations in Thai jasmine rice (Oryza sativa L. cv. KDML 105) to improve the yield and seed quality. Seeds of BKOS6, a Thai jasmine rice mutant previously induced by ion beams, were re-bombarded with 60-kV-accelerated N-ions (N++N2+) to fluences of 1-2 × 1016 ions/cm2. The resulting mutant, named HyKOS21, exhibited photoperiod insensitivity, semi-dwarfness, and high yield potential. Seed storability of the mutant was studied in natural and accelerated ageing conditions and compared to that of KDML 105 and six other Thai rice varieties. In both testing conditions, HyKOS21 mutant had the highest seed storability among the tested varieties. After storage in the natural condition for 18 months, HyKOS21 had a seed germination percentage nearly two times as that of the original KDML 105. Biochemical analysis showed that the lipid peroxidation level of the mutant seeds was the lowest among those of the tested varieties. Furthermore, an expression analysis of genes encoding lipoxygenase isoenzyme (lox1, lox2, and lox3) revealed that the mutant lacked expression of lox1 and lox2 and expressed only lox3 in seeds. These results may explain the improved seed longevity of the mutant after storage. This work provides further evidence of the modification of biological materials using a low-energy ion beam to produce rice mutants with improved yield and seed storability. The benefits of this technology, to create new varieties with improved values, could serve for local economic development.

  16. Genetic fingerprinting of mutant rose cultivars

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, S; Prasad, K V; Singh, K P; Singh, A.P. [Division of Floriculture and Landscaping, Indian Agricultural Research Institute, Pusa, New Delhi (India)], E-mail: kvprasad66@gmail.com

    2008-07-01

    Six rose mutants evolved at the Indian Agricultural Research Institute, New Delhi from four parent cultivars were characterized based on RAPD markers. Contrary to the earlier findings our effort has conclusively proven that the RAPD markers are indeed robust tools to discern the mutants from their parents. Among 40 primers screened, 7 primers produced inconsistent banding pattern. The number of polymorphic bands varied between 4 (OPA 14) and 10 (OPA1) with an average of 6.5 bands per primer. The percentage polymorphism ranged from 62.5 (OPM 9) to 100 percent (OPA 1). Most of the primers produced monomorphic bands between parent and mutant rose cultivars. When primer OPA 2 was used a specific band of 2.5 kb was noticed in mutant cv. Pusa Urmil and cv. Pusa Abhishek but was absent in parent cv. Jantar Mantar. A polymorphic band of 750 bp was noticed in the parent Kiss of Fire and helped in differentiating the parent from its mutant when amplified with OPK 3. Primer OPS 16 produced discriminatory band of 800 bp in mutant cv. Pink Sport of Montezuma while it was absent in its parent cv. Montezuma. Another specific band of 650 bp was present in parent cv. Montezuma and absent in its mutant cv. Pink Sport of Montezuma signifying the uniqueness of the mutant. Primer OPM 5 brought out distinct polymorphism among the parent Jantar Mantar and its three mutants with absence of a specific band of 1.5 kb in the parent. The four parents and 6 mutants were divided into four distinct groups in the Dendogram constructed by UPGMA method. The most genetically similar cultivar among the 10 cultivars analyzed are Montezuma and its pink sport of Montezuma whereas Abhisarika a mutant of cv. Kiss of Fire was distinctly different and formed a separate cluster. (author)

  17. Comparative Genome Analysis Between Aspergillus oryzae Strains Reveals Close Relationship Between Sites of Mutation Localization and Regions of Highly Divergent Genes among Aspergillus Species

    OpenAIRE

    Umemura, Myco; Koike, Hideaki; Yamane, Noriko; Koyama, Yoshinori; Satou, Yuki; Kikuzato, Ikuya; Teruya, Morimi; Tsukahara, Masatoshi; Imada, Yumi; Wachi, Youji; Miwa, Yukino; Yano, Shuichi; Tamano, Koichi; Kawarabayasi, Yutaka; Fujimori, Kazuhiro E.

    2012-01-01

    Aspergillus oryzae has been utilized for over 1000 years in Japan for the production of various traditional foods, and a large number of A. oryzae strains have been isolated and/or selected for the effective fermentation of food ingredients. Characteristics of genetic alterations among the strains used are of particular interest in studies of A. oryzae. Here, we have sequenced the whole genome of an industrial fungal isolate, A. oryzae RIB326, by using a next-generation sequencing system and ...

  18. Identification and toxigenic potential of the industrially important fungi, Aspergillus oryzae and Aspergillus sojae.

    Science.gov (United States)

    Jørgensen, Thomas R

    2007-12-01

    Mold strains belonging to the species Aspergillus oryzae and Aspergillus sojae are highly valued as koji molds in the traditional preparation of fermented foods, such as miso, sake, and shoyu, and as protein production hosts in modern industrial processes. A. oryzae and A. sojae are relatives of the wild molds Aspergillus flavus and Aspergillus parasiticus. All four species are classified to the A. flavus group. Strains of the A. flavus group are characterized by a high degree of morphological similarity. Koji mold species are generally perceived of as being nontoxigenic, whereas wild molds are associated with the carcinogenic aflatoxins. Thus, reliable identification of individual strains is very important for application purposes. This review considers the pheno- and genotypic markers used in the classification of A. flavus group strains and specifically in the identification of A. oryzae and A. sojae strains. Separation of A. oryzae and A. sojae from A. flavus and A. parasiticus, respectively, is inconsistent, and both morphologic and molecular evidence support conspecificity. The high degree of identity is reflected by the divergent identification of reference cultures maintained in culture collections. As close relatives of aflatoxin-producing wild molds, koji molds possess an aflatoxin gene homolog cluster. Some strains identified as A. oryzae and A. sojae have been implicated in aflatoxin production. Identification of a strain as A. oryzae or A. sojae is no guarantee of its inability to produce aflatoxins or other toxic metabolites. Toxigenic potential must be determined specifically for individual strains. The species taxa, A. oryzae and A. sojae, are currently conserved by societal issues.

  19. Grain Filling Characteristics and Their Relations with Endogenous Hormones in Large- and Small-Grain Mutants of Rice.

    Directory of Open Access Journals (Sweden)

    Weiyang Zhang

    Full Text Available This study determined if the variation in grain filling parameters between two different spikelet types of rice (Oryza sativa L. is regulated by the hormonal levels in the grains. Two rice mutants, namely, a large-grain mutant (AZU-M and a small-grain mutant (ZF802-M, and their respective wild types (AZU-WT and ZF802-WT were grown in the field. The endosperm cell division rate, filling rate, and hormonal levels: zeatin + zeatin riboside (Z+ZR, indo-3-acetic acid (IAA, polyamines (PAs, and abscisic acid (ABA were determined. The results showed that there was no significant difference between the filling and endosperm cell division rates. These rates were synchronous between the superior and inferior spikelets for both mutants. However, the abovementioned parameters were significantly different between the two spikelet types for the two wild types. The superior spikelets filled faster and their filling rate was higher compared to the inferior ones. Changes in the concentrations of plant hormones were consistent with the observed endosperm cell division rate and the filling rate for both types of spikelets of mutant and wild type plants. Regression analysis showed a significant positive correlation between cell division and filling rates with the concentrations of the investigated hormones. Exogenous chemical application verified the role of ABA, IAA, and PAs in grain filling. The results indicate that poor filling of inferior spikelets in rice occurs primarily due to the reduced hormone concentrations therein, leading to lower division rate of endosperm cells, fewer endosperm cells, slower filling rate, and smaller grain weight.

  20. Grain Filling Characteristics and Their Relations with Endogenous Hormones in Large- and Small-Grain Mutants of Rice.

    Science.gov (United States)

    Zhang, Weiyang; Cao, Zhuanqin; Zhou, Qun; Chen, Jing; Xu, Gengwen; Gu, Junfei; Liu, Lijun; Wang, Zhiqin; Yang, Jianchang; Zhang, Hao

    2016-01-01

    This study determined if the variation in grain filling parameters between two different spikelet types of rice (Oryza sativa L.) is regulated by the hormonal levels in the grains. Two rice mutants, namely, a large-grain mutant (AZU-M) and a small-grain mutant (ZF802-M), and their respective wild types (AZU-WT and ZF802-WT) were grown in the field. The endosperm cell division rate, filling rate, and hormonal levels: zeatin + zeatin riboside (Z+ZR), indo-3-acetic acid (IAA), polyamines (PAs), and abscisic acid (ABA) were determined. The results showed that there was no significant difference between the filling and endosperm cell division rates. These rates were synchronous between the superior and inferior spikelets for both mutants. However, the abovementioned parameters were significantly different between the two spikelet types for the two wild types. The superior spikelets filled faster and their filling rate was higher compared to the inferior ones. Changes in the concentrations of plant hormones were consistent with the observed endosperm cell division rate and the filling rate for both types of spikelets of mutant and wild type plants. Regression analysis showed a significant positive correlation between cell division and filling rates with the concentrations of the investigated hormones. Exogenous chemical application verified the role of ABA, IAA, and PAs in grain filling. The results indicate that poor filling of inferior spikelets in rice occurs primarily due to the reduced hormone concentrations therein, leading to lower division rate of endosperm cells, fewer endosperm cells, slower filling rate, and smaller grain weight.

  1. Generation and characterization of pigment mutants of ...

    African Journals Online (AJOL)

    Compared to the wild CC-124, these mutants are characterized by a decrease in chlorophyll a & b content and an increase in carotenoids. The lowest decrease in chlorophyll a was 3 to 4 folds, while the highest increase in carotenoids was 2 to 4 folds. The result of bio-test, using the resulting pigment mutant of C. reinhardtii ...

  2. A mutant of a mutant of a mutant of a ...: Irradiation of progressive radiation-induced mutants in a mutation-breeding programme with Chrysanthenum morifolium RAM

    International Nuclear Information System (INIS)

    Broertjes, C.; Koene, P.; Veen, J.W.H. van.

    1980-01-01

    Radiation-induced sports in Chrysanthemum morifolium RAM. have been reported for several years. It has become an everyday practice to produce flower-colour mutants from outstanding cross-breeding products, even before they are distributed for the commercial production of cut flowers. One of the most successful and recent examples is that of cv. Horim, of which hundreds of mutants were produced by successive use of radiation-induced mutants in the mutation-breeding programme. Over about 4 years a variety of flower-colour mutants was obtained, not only largely including the outstanding characteristics of the original cultivar but sometimes even with an appreciable improvement in quality and yield. It is expected that the latter types, the Miros group, will soon completely supersede the spontaneous or raditation-induced Horim sports and mutants and take over the leading position of the Horim group in the production of all-year-round (AYR) cut-flowers. (orig.)

  3. Gamma radiation-induced mutant of NSIC RC144 with broad-spectrum resistance to bacterial blight

    International Nuclear Information System (INIS)

    Alfonso, A.A.; Avellanoza, E.S.; Miranda, R.T.; Espejo, E.O.; Garcia, N.S.

    2014-01-01

    Mutant lines derived from gamma radiation-treated commercial variety NSIC RC144 were produced and screened for novel resistance to bacterial blight, one of the most serious diseases of rice. Preliminary screening of a bulk M2 population through induced method using race 3 of the pathogen Xanthomonas oryzae pv. oryzae (Xoo) resulted in the selection of 89 resistant plants. Subsequent repeated bacterial blight screenings and generation advance for five seasons resulted in the selection of two highly resistant M7 sister lines whose origin can be traced to a single M2 plant. DNA fingerprinting using 63 genome-wide simple sequence repeat (SSR) markers revealed an identical pattern in these lines. Using the same set of markers, they also exhibited 98% similarity to wild type NSIC RC144 indicating that the resistance is due to mutation and not due to genetic admixture or seed impurity. Two seasons of bacterial blight screening using 14 local isolates representing ten races of Xoo revealed an identical reaction pattern in these lines. The reaction pattern was observed to be unique compared to known patterns in four IRBB isolines (IRBB 4, 5, 7 and 21) with strong resistant reaction to bacterial blight suggesting possible novel resistance. The susceptible reaction in F1 testcrosses using Xoo race 6 and the segregation patterns in two F2 populations that fit with the expected 3 susceptible: 1 resistant ratio (P = 0.4, ns) suggest a single-gene recessive mutation in these lines. These mutants are now being used as resistance donor in the breeding program while further molecular characterization to map and characterize the mutated gene is being pursued

  4. Robustness and Strategies of Adaptation among Farmer Varieties of African Rice (Oryza glaberrima) and Asian Rice (Oryza sativa) across West Africa

    NARCIS (Netherlands)

    Mokuwa, A.; Nuijten, H.A.C.P.; Okry, F.; Teeken, B.W.E.; Maat, H.; Richards, P.; Struik, P.C.

    2013-01-01

    This study offers evidence of the robustness of farmer rice varieties (Oryza glaberrima and O. sativa) in West Africa. Our experiments in five West African countries showed that farmer varieties were tolerant of sub-optimal conditions, but employed a range of strategies to cope with stress.

  5. Expression, crystallization and preliminary X-ray crystallographic analysis of Xoo0352, d-alanine-d-alanine ligase A, from Xanthomonas oryzae pv. oryzae

    International Nuclear Information System (INIS)

    Doan, Thanh Thi Ngoc; Kim, Jin-Kwang; Kim, Hyesoon; Ahn, Yeh-Jin; Kim, Jeong-Gu; Lee, Byoung-Moo; Kang, Lin-Woo

    2008-01-01

    Xoo0352, which encodes d-alanine-d-alanine ligase A (DdlA), from X. oryzae pv. oryzae was cloned, purified and crystallized. Preliminary X-ray crystallographic analysis of DdlA crystals was performed. Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight (BB), which is one of the most devastating diseases of rice in most rice-growing countries. d-Alanine-d-alanine ligase A (DdlA), coded by the Xoo0352 gene, was expressed, purified and crystallized. DdlA is an enzyme that is involved in d-alanine metabolism and the biosynthesis of an essential bacterial peptidoglycan precursor, in which it catalyzes the formation of d-alanyl-d-alanine from two d-alanines, and is thus an attractive antibacterial drug target against Xoo. The DdlA crystals diffracted to 2.3 Å resolution and belonged to the primitive tetragonal space group P4 3 2 1 2, with unit-cell parameters a = b = 83.0, c = 97.6 Å. There is one molecule in the asymmetric unit, with a corresponding V M of 1.88 Å 3 Da −1 and a solvent content of 34.6%. The initial structure was determined by molecular replacement using d-alanine-d-alanine ligase from Staphylococcus aureus as a template model

  6. Los mutantes de la escuela

    Directory of Open Access Journals (Sweden)

    Diego Armando Jaramillo-Ocampo

    2013-01-01

    Full Text Available El presente artículo muestra los resultados parciales del estudio “Juegos en el recreo escolar: un escenario para la formación ciudadana”, cuya pretensión fue comprender los imaginarios sociales de juego en el recreo escolar y su relación con la convivencia social desde la proximidad del enfoque de complementariedad y el diseño de investigación emergente, planteado por Murcia y Jaramillo (2008. Se presentan los desarrollos logrados en dos categorías centrales del estudio: el patio y el cuerpo; dos categorías que mutan constantemente como entidades vivas en la escuela, hacia la configuración de sujetos que reconocen en el otro y lo otro su posibilidad. La escuela viva, donde es posible “ser en relación con”… se reduce a un espacio temporal y físico, limitado por la campana, “el recreo”. El texto muestra, desde la voz de los actores, esa vida que se da y se quita en la escuela y que se posiciona como una más de las imposiciones normalizadas para controlar. Reconoce, finalmente, una propuesta desde la posibilidad que estos dos mutantes propician para una escuela libre y dinámica.

  7. Substituting Both the N-Terminal and "Cord" Regions of a Xylanase from Aspergillus oryzae to Improve Its Temperature Characteristics.

    Science.gov (United States)

    Li, Chuang; Li, Jianfang; Wang, Rui; Li, Xueqing; Li, Jinping; Deng, Chao; Wu, Minchen

    2018-02-06

    To improve the temperature characteristics of AoXyn11A, a mesophilic glycoside hydrolase family (GHF) 11 xylanase from Aspergillus oryzae CICC40186, its N-terminal and "cord" regions were selected to be substituted by means of the computer-aided analysis and calculation. In brief, one mutant, named ATX11A 41 , possessing the lowest root-mean-square deviation (RMSD) value was designed based on the molecular dynamics (MD) simulation by substituting the N-terminal 41 amino acids of AoXyn11A with the corresponding 42 ones of pXYL11, a thermophilic GHF11 xylanase from Thermobifida fusca. On the basis of the primary structure alignment of pXYL11 with ATX11A 41 (or AoXyn11A), another mutant, named ATX11A 41/cord , was designed by substituting the cord region ( 93 GTYNPGSGG 101 ) of ATX11A 41 with the corresponding one ( 93 GTYRPTG 99 ) of pXYL11. Both mutant-encoding genes, ATx11A 41 and ATx11A 41/cord , were constructed as designed theoretically by a megaprimer PCR technique and were expressed in Pichia pastoris GS115. The specific activities of recombinant (re) AoXyn11A, ATX11A 41 , and ATX11A 41/cord were 2916.7, 2667.6, and 2457.0 U/mg, respectively. The analysis of temperature characteristics displayed that the temperature optimum (T opt ) of reATX11A 41 or reATX11A 41/cord was 65 °C, which was 15 °C higher than that of reAoXyn11A. The thermal inactivation half-life (t 1/2 ) values of reATX11A 41 and reATX11A 41/cord at 60 °C were 55 and 83 min, respectively, whereas that of reAoXyn11A was only 18 min at 50 °C. The melting temperature (T m ) values of reAoXyn11A, reATX11A 41 , and reATX11A 41/cord were 54.2, 66.7, and 71.9 °C, respectively. In conclusion, the above findings indicated that the substitution of both the N-terminal and cord regions of a mesophilic AoXyn11A greatly contributed to its improved temperature characteristics.

  8. Degradação de deoxinivalenol (DON) e a atividade da enzima peroxidase durante fermentação submersa

    OpenAIRE

    Garda-Buffon, Jaqueline; Kupski, Larine; Badiale-Furlong, Eliana

    2011-01-01

    This work aims to evaluate deoxynivalenol degradation by Aspergillus oryzae and Rhizopus oryzae in a submerged fermentation system and to correlate it to the activity of oxydo-reductase enzymes. The submerged medium consisted of sterile distilled water contaminated with 50 μg of DON and 4 × 10(6) spore.mL-1 inoculum of Aspergillus oryzae and Rhizopus oryzae species, respectively in each experiment. Sampling was performed every 24 hours for monitoring the peroxidase specific activity, and ever...

  9. Identification of growth phenotype-related genes in Aspergillus oryzae by heterologous macroarray and suppression subtractive hybridization

    NARCIS (Netherlands)

    Biesebeke, R. te; Levin, A.; Sagt, C.; Bartels, J.; Goosen, T.; Ram, A.; Hondel, C. van den; Punt, P.

    2005-01-01

    Aspergillus oryzae requires polarized growth for colonization of solid substrates, and this growth phenotype differs from that seen in liquid medium. Various experimental approaches were used to identify genes that are differentially expressed when A. oryzae is grown on wheat kernels and in a

  10. L-lactic acid production from starch by simultaneous saccharification and fermentation in a genetically engineered Aspergillus oryzae pure culture.

    Science.gov (United States)

    Wakai, Satoshi; Yoshie, Toshihide; Asai-Nakashima, Nanami; Yamada, Ryosuke; Ogino, Chiaki; Tsutsumi, Hiroko; Hata, Yoji; Kondo, Akihiko

    2014-12-01

    Lactic acid is a commodity chemical that can be produced biologically. Lactic acid-producing Aspergillus oryzae strains were constructed by genetic engineering. The A. oryzae LDH strain with the bovine L-lactate dehydrogenase gene produced 38 g/L of lactate from 100g/L of glucose. Disruption of the wild-type lactate dehydrogenase gene in A. oryzae LDH improved lactate production. The resulting strain A. oryzae LDHΔ871 produced 49 g/L of lactate from 100g/L of glucose. Because A. oryzae strains innately secrete amylases, A. oryzae LDHΔ871 produced approximately 30 g/L of lactate from various starches, dextrin, or maltose (all at 100 g/L). To our knowledge, this is the first report describing the simultaneous saccharification and fermentation of lactate from starch using a pure culture of transgenic A. oryzae. Our results indicate that A. oryzae could be a promising host for the bioproduction of useful compounds such as lactic acid. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Expression of Aspergillus hemoglobin domain activities in Aspergillus oryzae grown on solid substrates improves growth rate and enzyme production

    NARCIS (Netherlands)

    Biesebeke, te R.; Boussier, A.; Biezen van, N.; Braaksma, M.; Hondel, van den C.A.M.J.J.; Vos, de W.M.; Punt, P.J.

    2006-01-01

    DNA fragments coding for hemoglobin domains (HBD) were isolated from Aspergillus oryzae and Aspergillus niger. The HBD activities were expressed in A. oryzae by introduction of HBD gene fragments under the control of the promoter of the constitutively expressed gpdA gene. In the transformants,

  12. Autolysis of Aspergillus oryzae Mycelium and Effect on Volatile Flavor Compounds of Soy Sauce.

    Science.gov (United States)

    Xu, Ning; Liu, Yaqi; Hu, Yong; Zhou, Mengzhou; Wang, Chao; Li, Dongsheng

    2016-08-01

    The autolyzed mycelia of Aspergillus oryzae are rich in proteins, nucleic acids, sugar, and other biomacromolecules, and are one of the main contributors to the flavor profile of commercially important fermented goods, including soy sauce and miso. We induced autolysis of the mycelia of A. oryzae over 1 to 10 d, and found that the maximum dissolved amounts of total protein and nucleic acid ratio accounted for 28.63% and 88.93%, respectively. The organic acid content, such as citric acid, tartaric acid, succinic acid, lactic acid, and acetic acid, initially increased and then decreased as autolysis progressed, corresponding to changes in pH levels. The main characteristic flavor compounds in soy sauce, namely, ethanol, 2-phenylethanol, and 2-methoxy-4-vinylphenol, were all detected in the autolysate. Subsequently, we tested the effect of adding mycelia of A. oryzae during the fermentation process of soy sauce for 60 d, and found that addition of 1.2‰ A. oryzae mycelia provided the richest flavor. Overall, our findings suggest that compounds found in the autolysate of A. oryzae may promote the flavor compounds of soy sauce, such as alcohols, aldehydes, phenols, and esters. © 2016 Institute of Food Technologists®

  13. Pathway and rate-limiting step of glyphosate degradation by Aspergillus oryzae A-F02.

    Science.gov (United States)

    Fu, Gui-Ming; Chen, Yan; Li, Ru-Yi; Yuan, Xiao-Qiang; Liu, Cheng-Mei; Li, Bin; Wan, Yin

    2017-09-14

    Aspergillus oryzae A-F02, a glyphosate-degrading fungus, was isolated from an aeration tank in a pesticide factory. The pathway and rate-limiting step of glyphosate (GP) degradation were investigated through metabolite analysis. GP, aminomethylphosphonic acid (AMPA), and methylamine were detected in the fermentation liquid of A. oryzae A-F02, whereas sarcosine and glycine were not. The pathway of GP degradation in A. oryzae A-F02 was revealed: GP was first degraded into AMPA, which was then degraded into methylamine. Finally, methylamine was further degraded into other products. Investigating the effects of the exogenous addition of substrates and metabolites showed that the degradation of GP to AMPA is the rate-limiting step of GP degradation by A. oryzae A-F02. In addition, the accumulation of AMPA and methylamine did not cause feedback inhibition in GP degradation. Results showed that degrading GP to AMPA was a crucial step in the degradation of GP, which determines the degradation rate of GP by A. oryzae A-F02.

  14. Comparative Chemistry of Aspergillus oryzae (RIB40) and A. flavus (NRRL 3357)

    Science.gov (United States)

    Rank, Christian; Klejnstrup, Marie Louise; Petersen, Lene Maj; Kildgaard, Sara; Frisvad, Jens Christian; Gotfredsen, Charlotte Held; Larsen, Thomas Ostenfeld

    2012-01-01

    Aspergillus oryzae and A. flavus are important species in industrial biotechnology and food safety and have been some of the first aspergilli to be fully genome sequenced. Bioinformatic analysis has revealed 99.5% gene homology between the two species pointing towards a large coherence in the secondary metabolite production. In this study we report on the first comparison of secondary metabolite production between the full genome sequenced strains of A. oryzae (RIB40) and A. flavus (NRRL 3357). Surprisingly, the overall chemical profiles of the two strains were mostly very different across 15 growth conditions. Contrary to previous studies we found the aflatrem precursor 13-desoxypaxilline to be a major metabolite from A. oryzae under certain growth conditions. For the first time, we additionally report A. oryzae to produce parasiticolide A and two new analogues hereof, along with four new alkaloids related to the A. flavus metabolites ditryptophenalines and miyakamides. Generally the secondary metabolite capability of A. oryzae presents several novel end products likely to result from the domestication process from A. flavus. PMID:24957367

  15. An overproduction of astellolides induced by genetic disruption of chromatin-remodeling factors in Aspergillus oryzae.

    Science.gov (United States)

    Shinohara, Yasutomo; Kawatani, Makoto; Futamura, Yushi; Osada, Hiroyuki; Koyama, Yasuji

    2016-01-01

    The filamentous fungus Aspergillus oryzae is an important industrial mold. Recent genomic analysis indicated that A. oryzae has a large number of biosynthetic genes for secondary metabolites (SMs), but many of the SMs they produce have not been identified. For better understanding of SMs production by A. oryzae, we screened a gene-disruption library of transcription factors including chromatin-remodeling factors and found two gene disruptions that show similarly altered SM production profiles. One is a homolog of Aspergillus nidulans cclA, a component of the histone 3 lysine 4 (H3K4) methyltransferase complex of proteins associated with Set1 complex, and the other, sppA, is an ortholog of Saccharomyces cerevisiae SPP1, another component of a complex of proteins associated with Set1 complex. The cclA and sppA disruptions in A. oryzae are deficient in trimethylation of H3K4. Furthermore, one of the SMs that increased in the cclA disruptant was identified as astellolide F (14-deacetyl astellolide B). These data indicate that both cclA and sppA affect production of SMs including astellolides by affecting the methylation status of H3K4 in A. oryzae.

  16. An evaluation of aflatoxin and cyclopiazonic acid production in Aspergillus oryzae.

    Science.gov (United States)

    Kim, Nam Yeun; Lee, Jin Hee; Lee, Inhyung; Ji, Geun Eog

    2014-06-01

    To date, edible fungi such as Aspergillus flavus var. oryzae (A. oryzae) has been considered as safe. However, some strains can produce mycotoxins. Thus, the biosynthetic ability to produce mycotoxins should be reevaluated to determine the safety of edible fungi. We analyzed the production of aflatoxins and cyclopiazonic acid (CPA) from edible fungi such as A. oryzae isolated from various Korean foods using multiplex PCR, enzyme-linked immunosorbent assay, and high-performance liquid chromatography (HPLC). In the multiplex PCR analysis of aflatoxin biosynthetic genes omtB, aflR, ver-1, and omtA, 5 of 19 Aspergillus strains produced all PCR products. Among them, aflatoxin B1 and aflatoxin B2 were detected from only A. flavus KACC 41403 by HPLC. Aflatoxins were not detected from the other four strains that produced all positive PCR bands. Aflatoxin also was not detected from 12 strains that had PCR patterns without aflR or ver-1 and from 2 strains that did not produce any of the expected PCR products. Only the seven A. oryzae strains that produced all of the positive PCR bands including the CPA biosynthetic genes maoA, dmaT, and pks-nrps produced CPA. CPA and aflatoxin production must be evaluated before A. oryzae strains are used for the development of fermented foods.

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

    Science.gov (United States)

    Liu, Lifang; Feizi, Amir; Österlund, Tobias; Hjort, Carsten; Nielsen, Jens

    2014-06-24

    The koji mold, Aspergillus oryzae is widely used for the production of industrial enzymes due to its particularly high protein secretion capacity and ability to perform post-translational modifications. However, systemic analysis of its secretion system is lacking, generally due to the poorly annotated proteome. Here we defined a functional protein secretory component list of A. oryzae using a previously reported secretory model of S. cerevisiae as scaffold. Additional secretory components were obtained by blast search with the functional components reported in other closely related fungal species such as Aspergillus nidulans and Aspergillus niger. To evaluate the defined component list, we performed transcriptome analysis on three α-amylase over-producing strains with varying levels of secretion capacities. Specifically, secretory components involved in the ER-associated processes (including components involved in the regulation of transport between ER and Golgi) were significantly up-regulated, with many of them never been identified for A. oryzae before. Furthermore, we defined a complete list of the putative A. oryzae secretome and monitored how it was affected by overproducing amylase. In combination with the transcriptome data, the most complete secretory component list and the putative secretome, we improved the systemic understanding of the secretory machinery of A. oryzae in response to high levels of protein secretion. The roles of many newly predicted secretory components were experimentally validated and the enriched component list provides a better platform for driving more mechanistic studies of the protein secretory pathway in this industrially important fungus.

  18. Rhizomucor miehei triglyceride lipase is processed and secreted from transformed Aspergillus oryzae.

    Science.gov (United States)

    Huge-Jensen, B; Andreasen, F; Christensen, T; Christensen, M; Thim, L; Boel, E

    1989-09-01

    The cDNA encoding the precursor of the Rhizomucor miehei triglyceride lipase was inserted in an Aspergillus oryzae expression vector. In this vector the expression of the lipase cDNA is under control of the Aspergillus oryzae alpha-amylase gene promoter and the Aspergillus niger glucoamylase gene terminator. The recombinant plasmid was introduced into Aspergillus oryzae, and transformed colonies were selected and screened for lipase expression. Lipase-positive transformants were grown in a small fermentor, and recombinant triglyceride lipase was purified from the culture broth. The purified enzymatically active recombinant lipase (rRML) secreted from A. oryzae was shown to have the same characteristics with respect to mobility on reducing SDS-gels and amino acid composition as the native enzyme. N-terminal amino acid sequencing indicated that approximately 70% of the secreted rRML had the same N-terminal sequence as the native Rhizomucor miehei enzyme, whereas 30% of the secreted rRML was one amino acid residue shorter in the N-terminal. The recombinant lipase precursor, which has a 70 amino acid propeptide, is thus processed in and secreted from Aspergillus oryzae. We have hereby demonstrated the utility of this organism as a host for the production of recombinant triglyceride lipases.

  19. Utilization of Aspergillus oryzae to produce pectin lyase from various agro-industrial residues

    Directory of Open Access Journals (Sweden)

    Safia Koser

    2014-07-01

    Full Text Available The present study was aimed to investigate the culture influence on pectin lyase production potential of fungal strain Aspergillus oryzae. The enzyme profile of A. oryzae showed highest activity of pectin lyase after 3rd day of incubation on lemon peel waste under solid state fermentation conditions. To induce the pectin lyase synthesis capability of A. oryzae at optimal level various culture variables including physical and nutritional parameters were optimized by adopting classical optimization technique. Therefore, through fermentation process optimization the production of pectin lyase was substantially induced up to the level of 875 U/mL, when fermentation medium of lemon peel waste inoculated with 5 mL spore suspension of A. oryzae. The optimal fermentation conditions for maximum pectin lyase yield were as: optimum pH 5, 70% moisture level and incubated at 40 °C in addition with 1% sterile glucose solution as readily available carbon source and 0.2% yeast extract as an inexpensive nitrogen supplement (1%. The results obtained in current investigation so far demonstrated that culture conditions have great influence on the pectin lyase production potential of A. oryzae.

  20. Induction of Mutants in Durum Wheat

    International Nuclear Information System (INIS)

    AL-Ubaidi, M.; Ibrahim, I.; AL-Hadithi, A.

    2002-01-01

    This investigation presents a breeding program for induction and development of a new genotype of durum wheat, resistant to lodging with high yield, by irradiation durum wheat hybrids (F2) with gamma rays 100 Gy, during 1990-1997 cultivation seasons. This program involves: induction of variability, selection evaluation of the mutants at three locations: Twaitha (Baghdad) Latifya ( Babylon) and Swari (Kutt). All mutants showed resistance to lodging and there was a significant reduction in plant height. Mutant SIXIZ-22 surpassed other mutants and its origin in lodging resistance and plant height (83.5,82.8 and 89.4 cm) in the three locations at generation M5 and M6, respectively. Also, there were significant differences between mutant and their origin in the number of spikes/M 2 and grain yild during the two successive generation. On the other hand, mutant IZxCO-105 surpassed other mutants in the number of spikes/M 2 (231.8,242.3 and 292) and grain yield (4336,3376 and 5232 kg/ha) in all testing location, respectively . (authors) 14 refs., 4 tabs

  1. Magnaporthe oryzae Glycine-Rich Secretion Protein, Rbf1 Critically Participates in Pathogenicity through the Focal Formation of the Biotrophic Interfacial Complex.

    Directory of Open Access Journals (Sweden)

    Takeshi Nishimura

    2016-10-01

    Full Text Available Magnaporthe oryzae, the fungus causing rice blast disease, should contend with host innate immunity to develop invasive hyphae (IH within living host cells. However, molecular strategies to establish the biotrophic interactions are largely unknown. Here, we report the biological function of a M. oryzae-specific gene, Required-for-Focal-BIC-Formation 1 (RBF1. RBF1 expression was induced in appressoria and IH only when the fungus was inoculated to living plant tissues. Long-term successive imaging of live cell fluorescence revealed that the expression of RBF1 was upregulated each time the fungus crossed a host cell wall. Like other symplastic effector proteins of the rice blast fungus, Rbf1 accumulated in the biotrophic interfacial complex (BIC and was translocated into the rice cytoplasm. RBF1-knockout mutants (Δrbf1 were severely deficient in their virulence to rice leaves, but were capable of proliferating in abscisic acid-treated or salicylic acid-deficient rice plants. In rice leaves, Δrbf1 inoculation caused necrosis and induced defense-related gene expression, which led to a higher level of diterpenoid phytoalexin accumulation than the wild-type fungus did. Δrbf1 showed unusual differentiation of IH and dispersal of the normally BIC-focused effectors around the short primary hypha and the first bulbous cell. In the Δrbf1-invaded cells, symplastic effectors were still translocated into rice cells but with a lower efficiency. These data indicate that RBF1 is a virulence gene essential for the focal BIC formation, which is critical for the rice blast fungus to suppress host immune responses.

  2. Development of a genome editing technique using the CRISPR/Cas9 system in the industrial filamentous fungus Aspergillus oryzae.

    Science.gov (United States)

    Katayama, Takuya; Tanaka, Yuki; Okabe, Tomoya; Nakamura, Hidetoshi; Fujii, Wataru; Kitamoto, Katsuhiko; Maruyama, Jun-Ichi

    2016-04-01

    To develop a genome editing method using the CRISPR/Cas9 system in Aspergillus oryzae, the industrial filamentous fungus used in Japanese traditional fermentation and for the production of enzymes and heterologous proteins. To develop the CRISPR/Cas9 system as a genome editing technique for A. oryzae, we constructed plasmids expressing the gene encoding Cas9 nuclease and single guide RNAs for the mutagenesis of target genes. We introduced these into an A. oryzae strain and obtained transformants containing mutations within each target gene that exhibited expected phenotypes. The mutational rates ranged from 10 to 20 %, and 1 bp deletions or insertions were the most commonly induced mutations. We developed a functional and versatile genome editing method using the CRISPR/Cas9 system in A. oryzae. This technique will contribute to the use of efficient targeted mutagenesis in many A. oryzae industrial strains.

  3. Reduction of the degradation activity of umami-enhancing purinic ribonucleotide supplement in miso by the targeted suppression of acid phosphatases in the Aspergillus oryzae starter culture.

    Science.gov (United States)

    Marui, Junichiro; Tada, Sawaki; Fukuoka, Mari; Wagu, Yutaka; Shiraishi, Yohei; Kitamoto, Noriyuki; Sugimoto, Tatsuya; Hattori, Ryota; Suzuki, Satoshi; Kusumoto, Ken-Ichi

    2013-09-02

    Miso (fermented soybean paste) is a traditional Japanese fermented food, and is now used worldwide. The solid-state culture of filamentous fungus, Aspergillus oryzae, grown on rice is known as rice-koji, and is important as a starter for miso fermentation because of its prominent hydrolytic enzyme activities. Recently, commercial miso products have been supplemented with purinic ribonucleotides, such as inosine monophosphate (IMP) and guanine monophosphate, to enhance the characteristic umami taste of glutamate in miso. Because the purinic ribonucleotides are degraded by enzymes such as acid phosphatases in miso, heat inactivation is required prior to the addition of these flavorings. However, heat treatment is a costly process and reduces the quality of miso. Therefore, an approach to lower acid phosphatase activities in koji culture is necessary. Transcriptional analysis using an A. oryzae KBN8048 rice-koji culture showed that eight of the 13 acid phosphatase (aph) genes were significantly down-regulated by the addition of phosphoric acid in the preparation of the culture in a concentration-dependent manner, while aphC expression was markedly up-regulated under the same conditions. The eight down-regulated genes might be under the control of the functional counterpart of the Saccharomyces cerevisiae transcriptional activator Pho4, which specifically regulates phosphatase genes in response to the ambient phosphate availability. However, the regulatory mechanism of aphC was not clear. The IMP dephosphorylation activities in rice-koji cultures of KBN8048 and the aphC deletion mutant (ΔaphC) were reduced by up to 30% and 70%, respectively, in cultures with phosphoric acid, while protease and amylase activity, which is important for miso fermentation, was minimally affected. The miso products fermented using the rice-koji cultures of KBN8048 and ΔaphC prepared with phosphoric acid had reductions in IMP dephosphorylation activity of 80% and 90%, respectively, without

  4. The Production of Benzaldehyde by Rhizopus oligosporus USM R1 in a Solid State Fermentation (SSF System of Soy Bean Meal: Rice Husks

    Directory of Open Access Journals (Sweden)

    Norliza, A. W.

    2005-01-01

    Full Text Available The cultivation of Rhizopus oligosporus USM R1 for the production of benzaldehyde, a bitter cherry almond flavour was performed using soya bean meal and rice husks as the substrates. The identification of R. oligosporus USM R1 was performed based on the observation made under light microscope and scanning electron microscope (SEM. The optimum conditions for the SSF in a 250-ml Erlenmeyer flask system were 40% (v/w water content, substrate particle size of 0.7 mm; inoculum size of 1 x 10^5 spores/g substrate; incubation temperature of 30C; substrate amount of 7 g and the ratio of soy bean meal: rice husks of 50:50%. A maximum benzaldehyde production was obtained when the substrate was agitated after 48 hour for a 96 hour fermentation time. The highest benzaldehyde production obtained after 96 hour cultivation was 5.47 mg g-1 substrate. The supplementation of carbon and nitrogen sources in the substrate mixture revealed an enhancement in the growth and benzyldehyde production. A maximum production of benzaldehyde was obtained with the supplementation of L-phenylalanine, a precursor for benzaldehyde biosynthesis which gave 38.69 mg benzaldehyde/g substrate. This is approximately 6-folds higher compared to the substrates without the supplementation of L-phenylalanine.

  5. Enhanced production of raw starch degrading enzyme using agro-industrial waste mixtures by thermotolerant Rhizopus microsporus for raw cassava chip saccharification in ethanol production.

    Science.gov (United States)

    Trakarnpaiboon, Srisakul; Srisuk, Nantana; Piyachomkwan, Kuakoon; Sakai, Kenji; Kitpreechavanich, Vichien

    2017-09-14

    In the present study, solid-state fermentation for the production of raw starch degrading enzyme was investigated by thermotolerant Rhizopus microsporus TISTR 3531 using a combination of agro-industrial wastes as substrates. The obtained crude enzyme was applied for hydrolysis of raw cassava starch and chips at low temperature and subjected to nonsterile ethanol production using raw cassava chips. The agro-industrial waste ratio was optimized using a simplex axial mixture design. The results showed that the substrate mixture consisting of rice bran:corncob:cassava bagasse at 8 g:10 g:2 g yielded the highest enzyme production of 201.6 U/g dry solid. The optimized condition for solid-state fermentation was found as 65% initial moisture content, 35°C, initial pH of 6.0, and 5 × 10 6 spores/mL inoculum, which gave the highest enzyme activity of 389.5 U/g dry solid. The enzyme showed high efficiency on saccharification of raw cassava starch and chips with synergistic activities of commercial α-amylase at 50°C, which promotes low-temperature bioethanol production. A high ethanol concentration of 102.2 g/L with 78% fermentation efficiency was achieved from modified simultaneous saccharification and fermentation using cofermentation of the enzymatic hydrolysate of 300 g raw cassava chips/L with cane molasses.

  6. [State of Fungal Lipases of Rhizopus microsporus, Penicillium sp. and Oospora lactis in Border Layers Water-Solid Phase and Factors Affecting Catalytic Properties of Enzymes].

    Science.gov (United States)

    Khasanov, Kh T; Davranov, K; Rakhimov, M M

    2015-01-01

    We demonstrated that a change in the catalytic activity of fungal lipases synthesized by Rhizopus microsporus, Penicillium sp. and Oospora lactis and their ability to absorb on different sorbents depended on the nature of groups on the solid phase surface in the model systems water: lipid and water: solid phase. Thus, the stability of Penicillium sp. lipases increased 85% in the presence ofsorsilen or DEAE-cellulose, and 55% of their initial activity respectively was preserved. In the presence of silica gel and CM-cellulose, a decreased rate of lipid hydrolysis by Pseudomonas sp. enzymes was observed in water medium, and the hydrolysis rate increased by 2.4 and 1.5 times respectively in the presence of aminoaerosil and polykefamid. In an aqueous-alcohol medium, aminoaerosil and polykefamid decreased the rate of substrate hydrolysis by more than 30 times. The addition of aerosil to aqueous and aqueous-alcohol media resulted in an increase in the hydrolysis rate by 1.2-1.3 times. Sorsilen stabilized Penicillium sp. lipase activity at 40, 45, 50 and 55 degrees C. Either stabilization or inactivation of lipases was observed depending on the pH of the medium and the nature of chemical groups localized on the surface of solid phase. The synthetizing activity of lipases also changed depending on the conditions.

  7. Preparation of hydrolytic liquid from dried distiller's grains with solubles and fumaric acid fermentation by Rhizopus arrhizus RH 7-13.

    Science.gov (United States)

    Liu, Huan; Yue, Xuemin; Jin, Yuhan; Wang, Meng; Deng, Li; Wang, Fang; Tan, Tianwei

    2017-10-01

    Fumaric acid production from lignocellulosic materials is an alternative chemicals production system. This work investigated the suitable conditions for hydrolysis of dried distiller's grains with solubles (DDGS). The hydrolytic liquid was subsequently used for the production of fumaric acid. After optimizing the hydrolysis conditions, the most suitable concentration of H 2 SO 4 (2%), hydrolysis temperature (120 °C), hydrolysis time (100min) and solid/liquid ratio (1:10) were obtained. The yield of monosaccharides reached 258 mg/g DDGS and 15.88 g/L glucose, 7.53 g/L xylose and 2.35 g/L arabinose were obtained in unprocessed hydrolytic liquid. The furfural inhibitor in the hydrolytic liquid was also detected and the yield of it was reducing progressively in the pretreatment process. The ferment ability of the hydrolytic liquid from DDGS was tested through the process of fumaric acid production by Rhizopus arrhizus RH 7-13. The unprocessed hydrolytic liquid was not appropriate for the fermentation process. The yield of fumaric acid from the concentrated processed hydrolytic liquid reached 18.93 g/L, which was close to the yield of fermenting 80 g/L glucose. This result indicated that the commonly used carbon resource glucose could to some extent be replaced by processed hydrolytic liquid. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Spectrum of induced floral mutants in Petunia

    International Nuclear Information System (INIS)

    Padmaja, V.; Sudhakar, P.

    1987-01-01

    A total of six floral mutants of garden Petunia isolated from the populations raised from the seed treatment with γ-rays, 2, 4-D and sodium azide are described. Five of the mutants viz. stellata, Campyloflora, Rubriflora mixed, Grandiflora and Albiflora mixed originated as segregants in M 2 generation while the chimeral floral phenotype was expressed in M 1 generation itself. Breeding behaviour of these horticulturally interesting altered floral phenotypes were studied in subsequent generations and appropriate conclusions were drawn regarding mode of inheritance of the mutant traits. 15 refs., 4 figures, 1 table. (author)

  9. Physico-chemical and sensorial characteristics of rice (Oryza sativa L.) irradiated and the effect in Sitophilus oryzae L. development

    International Nuclear Information System (INIS)

    Zanao, Cintia Fernanda Pedroso

    2007-01-01

    Rice is exposed to injuries especially due to the attack of insects, which represent great qualitative and quantitative losses. The aim of the present research was to verify the viability of the gamma irradiation as rice (Oryza sativa L.) conservation method; its efficiency in the control of an important pest for stored grains Sitophilus oryzae L. and the effects that irradiation may present in irradiated grains in relation to the sensory aspect and starch alterations. Samples were composed of polished rice and the gamma irradiation dosages used were 0.5; 1.0; 3.0; and 5.0 kGy, and kept at room temperature. Analyses of the grain breakage percentages during processing and the longevity and reproduction of the rice weevil were performed. Analyses of the centesimal composition, phytic acid, apparent amylose content and starch paste properties were also conducted, as well as analyses of the rice color (instrumental) and acceptability (hedonic test), aimed at the determination of the raw and cooked rice sensory quality. It was verified that the gamma irradiation did not change the grain breakage percentage significantly and caused a negative effect on the insect development. Irradiation did not change the centesimal composition significantly. No significant values of phytic acid were found because during rice processing, the outer part (bran) containing 85-92% of total phytates was removed. Values from 17.33 to 18.44% for the apparent amylose content were found, and irradiation did not affect the rice starch amylose content significantly. The paste properties results were significantly changed, where reduction on the paste temperature, decrease on the time for the occurrence of the peak viscosity, reduction on the final viscosity values were observed. The retrogradation tendency became less intense in starches with increasing irradiation dosages. Statistical differences (p<0.05) were detected in the sensory aspect between irradiated and non-irradiated samples, and the

  10. Systematic analysis of rice (Oryza sativa) metabolic responses to herbivory.

    Science.gov (United States)

    Alamgir, Kabir Md; Hojo, Yuko; Christeller, John T; Fukumoto, Kaori; Isshiki, Ryutaro; Shinya, Tomonori; Baldwin, Ian T; Galis, Ivan

    2016-02-01

    Plants defend against attack from herbivores by direct and indirect defence mechanisms mediated by the accumulation of phytoalexins and release of volatile signals, respectively. While the defensive arsenals of some plants, such as tobacco and Arabidopsis are well known, most of rice's (Oryza sativa) defence metabolites and their effectiveness against herbivores remain uncharacterized. Here, we used a non-biassed metabolomics approach to identify many novel herbivory-regulated metabolic signatures in rice. Most were up-regulated by herbivore attack while only a few were suppressed. Two of the most prominent up-regulated signatures were characterized as phenolamides (PAs), p-coumaroylputrescine and feruloylputrescine. PAs accumulated in response to attack by both chewing insects, i.e. feeding of the lawn armyworm (Spodoptera mauritia) and the rice skipper (Parnara guttata) larvae, and the attack of the sucking insect, the brown planthopper (Nilaparvata lugens, BPH). In bioassays, BPH insects feeding on 15% sugar solution containing p-coumaroylputrescine or feruloylputrescine, at concentrations similar to those elicited by heavy BPH attack in rice, had a higher mortality compared to those feeding on sugar diet alone. Our results highlight PAs as a rapidly expanding new group of plant defence metabolites that are elicited by herbivore attack, and deter herbivores in rice and other plants. © 2015 John Wiley & Sons Ltd.

  11. Fe deficiency induced changes in rice (Oryza sativa L.) thylakoids.

    Science.gov (United States)

    Wang, Yuwen; Xu, Chao; Li, Kang; Cai, Xiaojie; Wu, Min; Chen, Guoxiang

    2017-01-01

    Iron deficiency is an important abiotic stress that limits productivity of crops all over the world. We selected a hybrid rice (Oryza sativa L.), LYPJ, which is super high-yield and widely cultured in China, to investigate changes in the components and structure of thylakoid membranes and photosynthetic performance in response to iron deficiency. Our results demonstrated that photosystem I (PSI) is the primary target for iron deficiency, while the changes in photosystem II (PSII) are important for rebuilding a balance in disrupted energy utilization and dissipation caused by differential degradation of photosynthetic components. The result of immunoblot analysis suggested that the core subunit PsaA declined drastically, while PsbA remained relatively stable. Furthermore, several organizational changes of the photosynthetic apparatus were found by BN-PAGE, including a marked decrease in the PSI core complexes, the Cytb 6 /f complex, and the trimeric form of the LHCII antenna, consistent with the observed unstacking grana. The fluorescence induction analysis indicated a descending PSII activity with energy dissipation enhanced markedly. In addition, we proposed that the crippled CO 2 assimilation could be compensated by the enhanced of phosphoenolpyruvate carboxylase (PEPC), which is suggested by the decreased ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and photosynthetic efficiency.

  12. Overproduction, Purification and Characterization of Adenylate Deaminase from Aspergillus oryzae.

    Science.gov (United States)

    Li, Shubo; Qian, Yi; Liang, Yunlong; Chen, Xinkuan; Zhao, Mouming; Guo, Yuan; Pang, Zongwen

    2016-12-01

    Adenylate deaminase (AMPD, EC 3.5.4.6) is an aminohydrolase that widely used in the food and medicine industries. In this study, the gene encoding Aspergillus oryzae AMPD was cloned and expressed in Escherichia coli. Induction with 0.75 mM isopropyl β-D-l-thiogalactopyranoside resulted in an enzyme activity of 1773.9 U/mL. Recombinant AMPD was purified to electrophoretic homogeneity using nickel affinity chromatography, and its molecular weight was calculated as 78.6 kDa. Purified AMPD exhibited maximal activity at 35 °C, pH 6.0 and 30 mM K + , with apparent K m and V max values of 2.7 × 10 -4  M and 77.5 μmol/mg/min under these conditions. HPLC revealed that recombinant AMPD could effectively catalyse the synthesis of inosine-5'-monophosphate (IMP) with minimal by-products, indicating high specificity and suggesting that it could prove useful for IMP production.

  13. Differential repression of arylsulphatase synthesis in Aspergillus oryzae.

    Science.gov (United States)

    Burns, G R; Wynn, C H

    1977-09-15

    1. The activities of the three arylsulphatases (arylsulphate sulphohydrolase, EC 3.1.6.1) of Aspergillus oryzae produced under a variety of repressing and non-repressing conditions were determined. 2. These enzymes exhibit different sensitivities to repression by inorganic sulphate. 3. Arylsulphatase I, but not arylsulphatases II and III, exhibits a transient de-repression in the early growth phase in sulphate media. 4. When the fungus is cultured in repressing media and subsequently transferred to non-repressing media, the synthesis of the three enzymes is non-co-ordinate. 5. Growth of the fungus in media containing choline O-sulphate or tyrosine O-sulphate as the sole source of sulphur results in complete de-repression of arylsulphatase I, But the synthesis of arylsulphatases II and III is essentially fully repressed. 6. The marked similarities between the repression characteristics of arylsulphatases II and III, contrasted with those of arylsulphatase I, indicate that the genetic locus of arylsulphatase I is distinct from that of arylsulphatases II and III, suggesting that there are distinct physiological roles for the enzyme.

  14. Rise of a Cereal Killer: The Biology of Magnaporthe oryzae Biotrophic Growth.

    Science.gov (United States)

    Fernandez, Jessie; Orth, Kim

    2018-01-23

    The rice blast fungus, Magnaporthe oryzae, causes one of the most destructive diseases of cultivated rice in the world. Infections caused by this recalcitrant pathogen lead to the annual destruction of approximately 10-30% of the rice harvested globally. The fungus undergoes extensive developmental changes to be able to break into plant cells, build elaborate infection structures, and proliferate inside host cells without causing visible disease symptoms. From a molecular standpoint, we are still in the infancy of understanding how M. oryzae manipulates the host during this complex multifaceted infection. Here, we describe recent advances in our understanding of the cell biology of M. oryzae biotrophic interaction and key molecular factors required for the disease establishment in rice cells. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Structural analysis of cerebrosides from Aspergillus fungi: the existence of galactosylceramide in A. oryzae.

    Science.gov (United States)

    Tani, Yasushi; Amaishi, Yasunori; Funatsu, Tori; Ito, Masahiro; Itonori, Saki; Hata, Yoji; Ashida, Hisashi; Yamamoto, Kenji

    2014-12-01

    Glucosylceramide and galactosylceramide were detected in three Aspergillus species: Aspergillus oryzae, Aspergillus sojae and Aspergillus. awamori, using borate-coated TLC. The cerebrosides from A. oryzae were further purified by ion exchange and iatrobeads column chromatographies with or without borate, and determined the composition of sugar, fatty acid and sphingoid base by GC/MS, MALDI-TOF/MS and (1)H-NMR. We identified them as β-glucosylceramide and β-galactosylceramide. The ceramide moiety of both cerebrosides consisted mainly of 2-hydroxystearic acid and either 9-methyl-octadeca-4, 8-sphingadienine or octadeca-4, 8-sphingadienine. To our knowledge, this is the first study to provide evidence for the presence of β-galactosylceramide in A. oryzae.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

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

  17. Deciphering the signaling mechanisms of the plant cell wall degradation machinery in Aspergillus oryzae

    DEFF Research Database (Denmark)

    Udatha, D. B. R. K. Gupta; Topakas, Evangelos; Salazar, Margarita Pena

    2015-01-01

    is required to rationally engineer filamentous fungi for more efficient bioconversion of different types of biomass. Results: In this study we focused on ten chemically defined inducers to drive expression of cellulases, hemicellulases and accessory enzymes in the model filamentous fungus Aspergillus oryzae....... oryzae genome were only partially explained by the chemical similarity of the enzyme inducers. Genes encoding enzymes that have attracted considerable interest such as cellobiose dehydrogenases and copper-dependent polysaccharide mono-oxygenases presented a substrate-specific induction. Several homology...... in 2360 reactions in the genome scale metabolic network of A. oryzae, was performed through a two-step molecular docking against the binding pockets of the transcription factors AoXlnR and AoAmyR. A total of six metabolites viz., sulfite (H2SO3), sulfate (SLF), uroporphyrinogen III (UPGIII), ethanolamine...

  18. Establishment of a new method to quantitatively evaluate hyphal fusion ability in Aspergillus oryzae.

    Science.gov (United States)

    Tsukasaki, Wakako; Maruyama, Jun-Ichi; Kitamoto, Katsuhiko

    2014-01-01

    Hyphal fusion is involved in the formation of an interconnected colony in filamentous fungi, and it is the first process in sexual/parasexual reproduction. However, it was difficult to evaluate hyphal fusion efficiency due to the low frequency in Aspergillus oryzae in spite of its industrial significance. Here, we established a method to quantitatively evaluate the hyphal fusion ability of A. oryzae with mixed culture of two different auxotrophic strains, where the ratio of heterokaryotic conidia growing without the auxotrophic requirements reflects the hyphal fusion efficiency. By employing this method, it was demonstrated that AoSO and AoFus3 are required for hyphal fusion, and that hyphal fusion efficiency of A. oryzae was increased by depleting nitrogen source, including large amounts of carbon source, and adjusting pH to 7.0.

  19. Identification and toxigenic potential of the industrially important fungi, Aspergillus oryzae and Aspergillus sojae

    DEFF Research Database (Denmark)

    Jørgensen, Thomas R

    2007-01-01

    Mold strains belonging to the species Aspergillus oryzae and Aspergillus sojae are highly valued as koji molds in the traditional preparation of fermented foods, such as miso, sake, and shoyu, and as protein production hosts in modern industrial processes. A. oryzae and A. sojae are relatives...... of the wild molds Aspergillus flavus and Aspergillus parasiticus. All four species are classified to the A. flavus group. Strains of the A. flavus group are characterized by a high degree of morphological similarity. Koji mold species are generally perceived of as being nontoxigenic, whereas wild molds...... are associated with the carcinogenic aflatoxins. Thus, reliable identification of individual strains is very important for application purposes. This review considers the pheno- and genotypic markers used in the classification of A. flavus group strains and specifically in the identification of A. oryzae and A...

  20. Recombinant expression, purification, and characterization of an acyl-CoA binding protein from Aspergillus oryzae.

    Science.gov (United States)

    Hao, Qing; Liu, Xiaoguang; Zhao, Guozhong; Jiang, Lu; Li, Ming; Zeng, Bin

    2016-03-01

    To characterize biochemically the lipid metabolism-regulating acyl-CoA binding protein (ACBP) from the industrially-important fungus Aspergillus oryzae. A full-length cDNA encoding a candidate ACBP from A. oryzae (AoACBP) was cloned and expressed in Escherichia coli as a maltose-binding protein (MBP) fusion protein. The MBP-AoACBP protein was purified by an amylose resin chromatography column. SDS-PAGE showed that MBP-AoACBP has an estimated molecular weight of 82 kDa. Microscale thermophoresis binding assay showed that the recombinant AoACBP displayed much greater affinity for palmitoyl-CoA (K d = 80 nM) than for myristoyl-CoA (K d = 510 nM), thus demonstrating the preference of AoACBP for long-chain acyl-CoA. The data support the identification of AoACBP as a long-chain ACBP in A. oryzae.

  1. Small kernel 1 encodes a pentatricopeptide repeat protein required for mitochondrial nad7 transcript editing and seed development in maize (Zea mays) and rice (Oryza sativa).

    Science.gov (United States)

    Li, Xiao-Jie; Zhang, Ya-Feng; Hou, Mingming; Sun, Feng; Shen, Yun; Xiu, Zhi-Hui; Wang, Xiaomin; Chen, Zong-Liang; Sun, Samuel S M; Small, Ian; Tan, Bao-Cai

    2014-09-01

    RNA editing modifies cytidines (C) to uridines (U) at specific sites in the transcripts of mitochondria and plastids, altering the amino acid specified by the DNA sequence. Here we report the identification of a critical editing factor of mitochondrial nad7 transcript via molecular characterization of a small kernel 1 (smk1) mutant in Zea mays (maize). Mutations in Smk1 arrest both the embryo and endosperm development. Cloning of Smk1 indicates that it encodes an E-subclass pentatricopeptide repeat (PPR) protein that is targeted to mitochondria. Loss of SMK1 function abolishes the C → U editing at the nad7-836 site, leading to the retention of a proline codon that is edited to encode leucine in the wild type. The smk1 mutant showed dramatically reduced complex-I assembly and NADH dehydrogenase activity, and abnormal biogenesis of the mitochondria. Analysis of the ortholog in Oryza sativa (rice) reveals that rice SMK1 has a conserved function in C → U editing of the mitochondrial nad7-836 site. T-DNA knock-out mutants showed abnormal embryo and endosperm development, resulting in embryo or seedling lethality. The leucine at NAD7-279 is highly conserved from bacteria to flowering plants, and analysis of genome sequences from many plants revealed a molecular coevolution between the requirement for C → U editing at this site and the existence of an SMK1 homolog. These results demonstrate that Smk1 encodes a PPR-E protein that is required for nad7-836 editing, and this editing is critical to NAD7 function in complex-I assembly in mitochondria, and hence to embryo and endosperm development in maize and rice. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

  2. Release of the repressive activity of rice DELLA protein SLR1 by gibberellin does not require SLR1 degradation in the gid2 mutant.

    Science.gov (United States)

    Ueguchi-Tanaka, Miyako; Hirano, Ko; Hasegawa, Yasuko; Kitano, Hidemi; Matsuoka, Makoto

    2008-09-01

    The rice (Oryza sativa) DELLA protein SLR1 acts as a repressor of gibberellin (GA) signaling. GA perception by GID1 causes SLR1 protein degradation involving the F-box protein GID2; this triggers GA-associated responses such as shoot elongation and seed germination. In GA-insensitive and GA biosynthesis mutants, SLENDER RICE1 (SLR1) accumulates to high levels, and the severity of dwarfism is usually correlated with the level of SLR1 accumulation. An exception is the GA-insensitive F-box mutant gid2, which shows milder dwarfism than mutants such as gid1 and cps even though it accumulates higher levels of SLR1. The level of SLR1 protein in gid2 was decreased by loss of GID1 function or treatment with a GA biosynthesis inhibitor, and dwarfism was enhanced. Conversely, overproduction of GID1 or treatment with GA(3) increased the SLR1 level in gid2 and reduced dwarfism. These results indicate that derepression of SLR1 repressive activity can be accomplished by GA and GID1 alone and does not require F-box (GID2) function. Evidence for GA signaling without GID2 was also provided by the expression behavior of GA-regulated genes such as GA-20oxidase1, GID1, and SLR1 in the gid2 mutant. Based on these observations, we propose a model for the release of GA suppression that does not require DELLA protein degradation.

  3. Heterologous Production of a Novel Cyclic Peptide Compound, KK-1, in Aspergillus oryzae

    Directory of Open Access Journals (Sweden)

    Akira Yoshimi

    2018-04-01

    Full Text Available A novel cyclic peptide compound, KK-1, was originally isolated from the plant-pathogenic fungus Curvularia clavata. It consists of 10 amino acid residues, including five N-methylated amino acid residues, and has potent antifungal activity. Recently, the genome-sequencing analysis of C. clavata was completed, and the biosynthetic genes involved in KK-1 production were predicted by using a novel gene cluster mining tool, MIDDAS-M. These genes form an approximately 75-kb cluster, which includes nine open reading frames, containing a non-ribosomal peptide synthetase (NRPS gene. To determine whether the predicted genes were responsible for the biosynthesis of KK-1, we performed heterologous production of KK-1 in Aspergillus oryzae by introduction of the cluster genes into the genome of A. oryzae. The NRPS gene was split in two fragments and then reconstructed in the A. oryzae genome, because the gene was quite large (approximately 40 kb. The remaining seven genes in the cluster, excluding the regulatory gene kkR, were simultaneously introduced into the strain of A. oryzae in which NRPS had already been incorporated. To evaluate the heterologous production of KK-1 in A. oryzae, gene expression was analyzed by RT-PCR and KK-1 productivity was quantified by HPLC. KK-1 was produced in variable quantities by a number of transformed strains, along with expression of the cluster genes. The amount of KK-1 produced by the strain with the greatest expression of all genes was lower than that produced by the original producer, C. clavata. Therefore, expression of the cluster genes is necessary and sufficient for the heterologous production of KK-1 in A. oryzae, although there may be unknown factors limiting productivity in this species.

  4. Enhanced Production of Bovine Chymosin by Autophagy Deficiency in the Filamentous Fungus Aspergillus oryzae

    Science.gov (United States)

    Maruyama, Jun-ichi; Kitamoto, Katsuhiko

    2013-01-01

    Aspergillus oryzae has been utilized as a host for heterologous protein production because of its high protein secretory capacity and food-safety properties. However, A. oryzae often produces lower-than-expected yields of target heterologous proteins due to various underlying mechanisms, including degradation processes such as autophagy, which may be a significant bottleneck for protein production. In the present study, we examined the production of heterologous protein in several autophagy (Aoatg) gene disruptants of A. oryzae. We transformed A. oryzae gene disruptants of Aoatg1, Aoatg13, Aoatg4, Aoatg8, or Aoatg15, with a bovine chymosin (CHY) expression construct and found that the production levels of CHY increased up to three fold compared to the control strain. Notably, however, conidia formation by the Aoatg gene disruptants was significantly reduced. As large amounts of conidia are necessary for inoculating large-scale cultures, we also constructed Aoatg gene-conditional expression strains in which the promoter region of the Aoatg gene was replaced with the thiamine-controllable thiA promoter. Conidiation by the resultant transformants was clearly enhanced in the absence of thiamine, while autophagy remained repressed in the presence of thiamine. Moreover, these transformants displayed increased CHY productivity, which was comparable to that of the Aoatg gene disruptants. Consequently, we succeeded in the construction of A. oryzae strains capable of producing high levels of CHY due to defects in autophagy. Our finding suggests that the conditional regulation of autophagy is an effective method for increasing heterologous protein production in A. oryzae. PMID:23658635

  5. Heterologous Production of a Novel Cyclic Peptide Compound, KK-1, in Aspergillus oryzae.

    Science.gov (United States)

    Yoshimi, Akira; Yamaguchi, Sigenari; Fujioka, Tomonori; Kawai, Kiyoshi; Gomi, Katsuya; Machida, Masayuki; Abe, Keietsu

    2018-01-01

    A novel cyclic peptide compound, KK-1, was originally isolated from the plant-pathogenic fungus Curvularia clavata . It consists of 10 amino acid residues, including five N -methylated amino acid residues, and has potent antifungal activity. Recently, the genome-sequencing analysis of C. clavata was completed, and the biosynthetic genes involved in KK-1 production were predicted by using a novel gene cluster mining tool, MIDDAS-M. These genes form an approximately 75-kb cluster, which includes nine open reading frames, containing a non-ribosomal peptide synthetase (NRPS) gene. To determine whether the predicted genes were responsible for the biosynthesis of KK-1, we performed heterologous production of KK-1 in Aspergillus oryzae by introduction of the cluster genes into the genome of A. oryzae . The NRPS gene was split in two fragments and then reconstructed in the A. oryzae genome, because the gene was quite large (approximately 40 kb). The remaining seven genes in the cluster, excluding the regulatory gene kkR , were simultaneously introduced into the strain of A. oryzae in which NRPS had already been incorporated. To evaluate the heterologous production of KK-1 in A. oryzae , gene expression was analyzed by RT-PCR and KK-1 productivity was quantified by HPLC. KK-1 was produced in variable quantities by a number of transformed strains, along with expression of the cluster genes. The amount of KK-1 produced by the strain with the greatest expression of all genes was lower than that produced by the original producer, C. clavata . Therefore, expression of the cluster genes is necessary and sufficient for the heterologous production of KK-1 in A. oryzae , although there may be unknown factors limiting productivity in this species.

  6. Efficient formation of heterokaryotic sclerotia in the filamentous fungus Aspergillus oryzae.

    Science.gov (United States)

    Wada, Ryuta; Jin, Feng Jie; Koyama, Yasuji; Maruyama, Jun-ichi; Kitamoto, Katsuhiko

    2014-01-01

    Heterokaryon formation by hyphal fusion occurs during a sexual/parasexual cycle in filamentous fungi, and therefore, it is biotechnologically important for crossbreeding. In the industrial filamentous fungus Aspergillus oryzae, a parasexual cycle has been reported, and it was recently suggested that sexual reproduction should be possible. However, as A. oryzae enters into hyphal fusion with a much lower frequency than Neurospora crassa, the process of heterokaryon formation has not been extensively characterized in A. oryzae. Here, we developed a detection system for heterokaryon formation by expressing red or green fluorescent proteins in nuclei and conferring uridine/uracil or adenine auxotrophy to MAT1-1 and MAT1-2 strains of A. oryzae. The heterokaryon formation of A. oryzae was investigated in paired culture using the genetically modified strains. No sclerotial formation was observed in the hyphal contact regions of the two strains with the same auxotrophy, whereas numerous sclerotia were formed between the strains with different auxotrophies. In most of the formed sclerotia, the uridine/uracil and adenine auxotrophies were complemented, and both red and green fluorescence were detected, indicating that heterokaryotic fusants were formed by hyphal fusion before or during sclerotial formation. Moreover, overexpressing the sclR gene, which encodes a transcription factor promoting sclerotial formation, increased the number of heterokaryotic sclerotia formed between the two auxotrophic strains. Notably, these effects in sclerotial formation of heterokaryotic fusants were observed independently of the mating type pairing combinations. Taken together, these findings demonstrated that paring of different auxotrophs and sclR overexpression promote the formation of heterokaryotic sclerotia in A. oryzae.

  7. Semi-dwarf mutants for rice improvement

    International Nuclear Information System (INIS)

    Othman, Ramli; Osman, Mohammad; Ibrahim, Rusli

    1990-01-01

    Full text: MARDI and the National University of Malaysia embarked on a programme to induce resistance against blast in rice in 1978. MARDI also obtained semi dwarf mutants of cvs 'Mahsuri', 'Muda', 'Pongsu seribu' and 'Jarum Mas', which are under evaluation. The popular local rice variety 'Manik' was subjected to gamma irradiation (15-40 krad) and 101 promising semidwarf mutants have been obtained following selection in M 2 -M 6 . 29 of them show grain yields of 6.0-7.3 t/ha, compared with 5.7t for 'Manik'. Other valuable mutants were found showing long grain, less shattering, earlier maturity, and glutinous endosperm. One mutant, resistant to brown plant hopper yields 6.3t/ha. (author)

  8. X-rays sensitive mammalian cell mutant

    International Nuclear Information System (INIS)

    Utsumi, Hiroshi

    1982-01-01

    A phenomenon that in x-ray-sensitive mammalian-cell mutants, cellular death due to x-ray radiation was not increased by caffeine, but on the contrary, the dead cells were resuscitated by it was discussed. The survival rate of mutant cells increased by caffein in a low concentration. This suggested that caffeine may have induced some mechanism to produce x-ray resistant mutant cells. Postirradiation treatment with caffeine increased considerably the survival rate of the mutant cells, and this suggested the existence of latent caffeine-sensitive potentially lethal damage repair system. This system, after a few hours, is thought to be substituted by caffeine-resistant repair system which is induced by caffeine, and this may be further substituted by x-ray-resistant repair system. The repair system was also induced by adenine. (Ueda, J.)

  9. Generation and characterization of pigment mutants of ...

    African Journals Online (AJOL)

    acer

    2014-01-08

    Jan 8, 2014 ... aquatic ecosystems were studied. In the present ... logy and photosynthesis research (Stolbov, 1995;. Pedersen ... Microalgal strain and cultivation conditions ..... evaluated for their ecotoxicological effects using 124y-1 mutant.

  10. Comparison of the genomes and transcriptomes associated with the different protease secretions of Aspergillus oryzae 100-8 and 3.042.

    Science.gov (United States)

    Zhao, Guozhong; Yao, Yunping; Hou, Lihua; Wang, Chunling; Cao, Xiaohong

    2014-10-01

    Aspergillus oryzae is used to produce traditional fermented foods and beverages. A. oryzae 3.042 produces a neutral protease and an alkaline protease but rarely an acid protease, which is unfavourable to soy-sauce fermentation. A. oryzae 100-8 was obtained by N(+) ion implantation mutagenesis of A. oryzae 3.042, and the protease secretions of these two strains are different. Sequencing the genome of A. oryzae 100-8 and comparing it to the genomes of A. oryzae 100-8 and 3.042 revealed some differences, such as single nucleotide polymorphisms, nucleotide deletion or insertion. Some of these differences may reflect the ability of A. oryzae to secrete proteases. Transcriptional sequencing and analysis of the two strains during the same growth processes provided further insights into the genes and pathways involved in protease secretion.

  11. The chemical heritage of Aspergillus flavus in A. oryzae RIB 40

    DEFF Research Database (Denmark)

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

    Aspergillus oryzae is a very important species in biotechnology and has been used for centuries in traditional Asian fermentation. The RIB40 strain is particularly interesting as it was one of the first genome sequenced Aspergilli together with A. flavus, a prominent food and feed contaminant...... capable of producing aflatoxin. These species can be perceived as ecotypes. We have analyzed A. oryzae RIB40 and found that the chemical potential could be enhanced significantly under certain conditions. Delicate analysis of their metabolic profiles allow for chemical insight on the transcription level...

  12. Kinetic studies of acid inactivation of alpha-amylase from Aspergillus oryzae

    DEFF Research Database (Denmark)

    Carlsen, Morten; Nielsen, Jens Bredal; Villadsen, John

    1996-01-01

    The stability of alpha-amylase from Aspergillus oryzae has been studied at different pH. The enzyme is extremely stable at neutral pH (pH 5-8), whereas outside this pH-range a substantial loss of activity is observed. The acid-inactivation of alpha-amylase from A. oryzae was monitored on...... regains part of its activity, and the reactivation process also follows first-order kinetics. The irreversible loss of activity is found not to result from a protease contamination of the protein samples. A proposed model, where irreversibly inactivated a-amylase is formed both directly from the active...

  13. Analysis of extracellular proteins of Aspergillus oryzae grown on soy sauce koji.

    Science.gov (United States)

    Liang, Yanchang; Pan, Li; Lin, Ying

    2009-01-01

    Aspergillus oryzae AS 3.951 is widely used in Chinese soy sauce manufacture, but little is known about the profiles of the extracellular proteins from the culture of soybean koji. In this study, we carried out MALDI-TOF/TOF MS analysis of extracellular proteins during koji culture. Besides well-known proteins (TAA and Oryzin), a variety of aminopeptidase and proteases were identical at the proteome level. This suggests that A. oryzae AS 3.951 has a powerful capacity to digest soybean protein.

  14. Pemanfaatan Ekstrak Tanaman Ketan Hitam (Oryza Sativa Glutinosa) sebagai Indikator Asam Basa

    OpenAIRE

    Hasibuan, Muhammad Arief; Amran, Elva Yasmi; ', Susilawati

    2016-01-01

    Research was conducted with the aims to determine pH range, percentage acid base indicator titration error, and stability of Oryza sativa Glutinosa extract as acid base indicator. Oryza sativa Glutinosa grains respectively extracted with maseration using ethanol (HCl 1%). pH range determined by added the extract into buffer solutions pH 1-9. Percentage acid base indicator titration error determined by applied the extract in strong acid-strong base, weak acid-strong base, strong acid-weak base...

  15. Sequence analysis and overexpression of a pectin lyase gene (pel1) from Aspergillus oryzae KBN616.

    Science.gov (United States)

    Kitamoto, N; Yoshino-Yasuda, S; Ohmiya, K; Tsukagoshi, N

    2001-01-01

    A gene (pel1) encoding pectin lyase (Pel1) was isolated from a shoyu koji mold, Aspergillus oryzae KBN616, and characterized. The structural gene comprised 1,196 bp with a single intron. The ORF encoded 381 amino acids with a signal peptide of 20 amino acids. The deduced amino acid sequence showed high similarity to those of Aspergillus niger pectin lyases and Glomerella cingulata PnlA. The pel1 gene was successfully overexpressed under the promoter of the A. oryzae TEF1 gene. The molecular mass of the recombinant pectin lyase substantially coincided with that calculated based on nucleotide sequence.

  16. High-yields heterologous production of the novel Aspergillus fumigatus elastase inhibitor AFUEI in Aspergillus oryzae.

    Science.gov (United States)

    Yamashita, Nobuo; Komori, Yumiko; Okumura, Yoshiyuki; Uchiya, Kei-Ichi; Matsui, Takeshi; Nishimura, Akira; Ogawa, Kenji; Nikai, Toshiaki

    2011-08-01

    AFUEI, an elastase inhibitor produced by Aspergillus fumigatus strongly inhibits the elastolytic activity of A. fumigatus etc. To purify AFUEI, we constructed a strain that overproduces AFUEI by introducing the gene encoding AFUEI (Genbank accession no. AB546725) under control of the amyB promoter into the heterologous host Aspergillus oryzae. A. oryzae TF-4 displayed strong elastase inhibitory activity and produced considerably more AFUEI than that of A. fumigatus. Furthermore, AFUEI could be purified using culture broth and single ultrafiltration (UF) treatment, allowing for the effective production of AFUEI for use in clinical trials. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  17. Molecular analysis of waxy mutants in rice

    International Nuclear Information System (INIS)

    Yatou, O.; Amano, E.

    1990-01-01

    Full text: The 'waxy' gene is a structural gene coding a glycosyl transferase which synthesises amylose in the endosperm tissue. 'Non-waxy' rice cultivars have an active gene and their amylose content is 18-25% depending upon gene performance and modifier genes. In 'waxy' rice, no amylose is found because the enzyme is absent. In mutants induced by gamma rays, neutrons, EI or EMS, amylose content ranged from 0 to 20%, i.e. there are intermediate phenotypes as well. Some of them had the same amount of the enzyme as a 'non-waxy' cultivar, even fully 'waxy' mutants showed a certain amount of the enzyme. This suggests that in mutants there may be no structural change in the enzyme gene but the enzyme produced might be less active. By molecular analysis of the mutants' genes it was found that only two mutants induced by thermal neutrons show structural alterations, the changes in other mutants are either too small to be detected by Southern analysis or are outside the structural gene in question. (author)

  18. Commercialization Of Orchid Mutants For Floriculture Industry

    International Nuclear Information System (INIS)

    Sakinah Ariffin; Zaiton Ahmad

    2014-01-01

    Orchids are the main contributors to cut flower industry in Malaysia with an existing good market and a huge business potential. Orchid industry has been established in Malaysia since 1960s but only started to develop and expand since 1980s. Continuous development of new orchid varieties is essential to meet customers' demands. Orchid mutagenesis research using gamma irradiation at Malaysian Nuclear Agency has successfully generated a number of new orchid varieties with commercial potentials. Therefore, Nuclear Malaysia has collaborated with an industrial partner, Hexagon Green Sdn Bhd (HGSB), to carry out commercialization research on these mutants under a Technofund project entitled 'Pre-Commercialization of Mutant Orchids for Cut Flowers Industry' from July 2011 to July 2014. Through this collaboration, Dendrobium orchid mutant plants developed by Nuclear Malaysia were transferred to HGSB's commercial orchid nursery at Bukit Changgang Agrotechnology Park, Banting, Selangor, for mass-propagation. The activities include evaluations on plant growth performance, flower quality, post harvest and market potential of these mutants. Mutants with good field performance have been identified and filed for Plant Variety Protection (PVP) with Department of Agriculture Malaysia. This paper describes outputs from this collaboration and activities undertaken in commercializing these mutants. (author)

  19. Genetic improvement of rice (oryza sativa l.) by induced mutations

    International Nuclear Information System (INIS)

    Suarez, E.; Deus, J. E.; Perez, R.; Alfonso, R.; Hernandez, R.; Avila, J.; Hernandez, J. L.; Puldon, Violeta; Duany, A.; Reinoso, J.; Mesa, H.; Rodriguez, S.

    2001-01-01

    In 1989 was initiated at Rice Research Institute of Cuba, a mutation breeding programme, in order to obtain new germoplasm with improved characters such as milling quality, earliness, resistance to the Hoja Blanca virus disease and salt tolerance. Seven varieties has been irradiated and two different sources of radiation were used: gamma rays from 60Co and fast neutrons of a 14 MeV neutron generator. In 1995, was released the variety IACuba 23 for low inputs conditions. Another four varieties IACuba 21, IACuba 22, IACuba 27 and IACuba 28 are in validation trials in rice production areas under irrigated condition. The last two have showed resistance to Steneotarsonemus spinki. Also, a group of mutants was selected to be used as parents. These mutants have been used in 953 crosses

  20. From one body mutant to one cell mutant. A progress of radiation breeding in crops

    International Nuclear Information System (INIS)

    Nagatomi, Shigeki

    1996-01-01

    An effective method was established to obtain non-chimeral mutants with wide spectrum of flower colors, regenerated from floral organs on which mutated sectors were come out on chronic irradiated plants. By this way, six mutant varieties of flower colors have been selected from one pink flower of chrysanthemum, and cultivated for cut-flower production. By the same method, 3 mutant varieties with small and spray type flowers were selected in Eustoma. Mutant varieties such as a rust disease resistant in sugarcane, 6 dwarfs in Cytisus and pure-white mushroom in velvet shank have been selected successively for short period. (J.P.N.)

  1. Gamma-radiation Mutagenesis in Genetically Unstable Barley Mutants. Pt. 2. Comparison of Various Mutants

    International Nuclear Information System (INIS)

    Balchiuniene, L.

    1995-01-01

    Spontaneous and gamma-induced mutability was compared in two groups of genetically unstable barley ear structure mutants - tweaky spike (tw) and branched ear (be). Instability in different loci causes different levels of spontaneous and gamma-induced mutability. A high spontaneous level of chlorophyll mutations is peculiar to be-ust mutants. It is suggested that the high level of induced chlorophyll mutations in allelic tw mutants is a result of better surviving of chlorophyll mutation carriers in the genotypical-physiological environment created by mutant tw alleles. (author). 6 refs., 2 tabs

  2. Bekatul (Oryza sativa L. Menghambat Peningkatan Kadar Kolesterol Darah

    Directory of Open Access Journals (Sweden)

    Astri Kania

    2014-02-01

    Full Text Available Abstrak Penyakit kardiovaskuler merupakan penyebab utama kematian dan kecacatan di seluruh dunia, termasuk Indonesia. Penyakit kardiovaskuler disebabkan oleh pembentukan aterosklerosis pada pembuluh darah. Konsumsi larutan tepung bekatul (Oryza sativa L. dapat digunakan sebagai salah satu upaya untuk mencegah terjadinya aterosklerosis dengan cara menghambat peningkatan kadar kolesterol darah. Penelitian ini untuk menilai efek larutan tepung bejatul terhadap penghambatan peningkatan kadar kolesterol darah. Penelitian eksperimental laboratorik dengan rancangan acak lengkap telah dilakukan pada 20 ekor tikus putih jantan galur Wistar yang dibagi menjadi lima kelompok. Kelompok I adalah kontrol negatif yang diberikan diet tinggi lemak dan propiltiurasil (PTU 0,01%, kelompok II merupakan kontrol positif yang hanya diberi pelet. Kelompok III, IV, dan V adalah kelompok perlakuan yang diberikan sediaan uji 0,27 gram/200 gram BB, 0,54 gram/200 gram BB, dan 1,08 gram/200 gram BB, DTL dan PTU 0,01% secara bersamaan. Pengukuran kadar kolesterol darah dilakukan sebelum diberikan perlakuan (hari ke-7 dan setelah diberikan perlakuan (hari ke-21 dengan menggunakan metode kolorimetrik enzimatik. Hasil penelitian ini menunjukkan bahwa larutan tepung bekatul memiliki efek penghambatan terhadap peningkatan kadar kolesterol darah dengan dosis 0,54 gram/200 gram BB. Efek penghambatan tersebut diakibatkan oleh mekanisme interaksi  dari orizanol, fitosterol, dan omega-3 yang terdapat dalam larutan tepung bekatul. Kata kunci: Bekatul, efek penghambatan, kolesterol darah   Rice Bran (Oryza sativa L. Inhibit the Increase of Blood Cholesterol Level Abstract Cardiovascular disease is the major cause of mortality and morbidity in the world, including Indonesia. This disease caused by atherosclerosis formation in blood vessel. Consumption of rice bran is one alternative to prevent atherosclerosis by inhibiting the increase of blood cholesterol level. The Aim of study was to

  3. Robustness and strategies of adaptation among farmer varieties of African Rice (Oryza glaberrima) and Asian Rice (Oryza sativa) across West Africa.

    Science.gov (United States)

    Mokuwa, Alfred; Nuijten, Edwin; Okry, Florent; Teeken, Béla; Maat, Harro; Richards, Paul; Struik, Paul C

    2013-01-01

    This study offers evidence of the robustness of farmer rice varieties (Oryza glaberrima and O. sativa) in West Africa. Our experiments in five West African countries showed that farmer varieties were tolerant of sub-optimal conditions, but employed a range of strategies to cope with stress. Varieties belonging to the species Oryza glaberrima - solely the product of farmer agency - were the most successful in adapting to a range of adverse conditions. Some of the farmer selections from within the indica and japonica subspecies of O. sativa also performed well in a range of conditions, but other farmer selections from within these two subspecies were mainly limited to more specific niches. The results contradict the rather common belief that farmer varieties are only of local value. Farmer varieties should be considered by breeding programmes and used (alongside improved varieties) in dissemination projects for rural food security.

  4. Patogenicidade de Helminthosporium oryzae a algumas espécies de gramíneas Pathogenicity of Helminthosporium oryzae against some grass species

    Directory of Open Access Journals (Sweden)

    V.H. Artigiani Filho

    1995-04-01

    Full Text Available O fungo Helminthosporium oryzae é um patógeno do arroz. Devido a sua variabilidade patogênica, foi investigada a possibilidade deste fungo infectar outras gramíneas. Através de inoculação artificial, ficou demonstrada a capacidade deste patógeno provocar infecção em aveia, cana, centeio, sorgo, trigo, Brachiaria decumbens e Panicum maximum. Assim, estas espécies vegetais podem ser consideradas potenciais hospedeiros do fungo na natureza.Helminthosporium oryzae is a rice pathogen. Due to its variability in pathogenicity, the possibility of this fungus Infecting other grasses was investigated. The capacity of this pathogen was demonstrated to be able to infect oat, sugar-cane, rye, sorghum, wheat, Brachiaria decumbens and Panicum maximum through artificial inoculations. Therefore, those plant species can be considered potencial hosts for the fungus in nature.

  5. Robustness and Strategies of Adaptation among Farmer Varieties of African Rice (Oryza glaberrima) and Asian Rice (Oryza sativa) across West Africa

    Science.gov (United States)

    Maat, Harro; Richards, Paul; Struik, Paul C.

    2013-01-01

    This study offers evidence of the robustness of farmer rice varieties (Oryza glaberrima and O. sativa) in West Africa. Our experiments in five West African countries showed that farmer varieties were tolerant of sub-optimal conditions, but employed a range of strategies to cope with stress. Varieties belonging to the species Oryza glaberrima – solely the product of farmer agency – were the most successful in adapting to a range of adverse conditions. Some of the farmer selections from within the indica and japonica subspecies of O. sativa also performed well in a range of conditions, but other farmer selections from within these two subspecies were mainly limited to more specific niches. The results contradict the rather common belief that farmer varieties are only of local value. Farmer varieties should be considered by breeding programmes and used (alongside improved varieties) in dissemination projects for rural food security. PMID:23536754

  6. Using the concept of pseudo amino acid composition to predict resistance gene against Xanthomonas oryzae pv. oryzae in rice: an approach from chaos games representation.

    Science.gov (United States)

    Jingbo, Xia; Silan, Zhang; Feng, Shi; Huijuan, Xiong; Xuehai, Hu; Xiaohui, Niu; Zhi, Li

    2011-09-07

    To evaluate the possibility of an unknown protein to be a resistant gene against Xanthomonas oryzae pv. oryzae, a different mode of pseudo amino acid composition (PseAAC) is proposed to formulate the protein samples by integrating the amino acid composition, as well as the Chaos games representation (CGR) method. Some numerical comparisons of triangle, quadrangle and 12-vertex polygon CGR are carried to evaluate the efficiency of using these fractal figures in classifiers. The numerical results show that among the three polygon methods, triangle method owns a good fractal visualization and performs the best in the classifier construction. By using triangle + 12-vertex polygon CGR as the mathematical feature, the classifier achieves 98.13% in Jackknife test and MCC achieves 0.8462. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Small brown planthopper resistance loci in wild rice (Oryza officinalis).

    Science.gov (United States)

    Zhang, Weilin; Dong, Yan; Yang, Ling; Ma, Bojun; Ma, Rongrong; Huang, Fudeng; Wang, Changchun; Hu, Haitao; Li, Chunshou; Yan, Chengqi; Chen, Jianping

    2014-06-01

    Host-plant resistance is the most practical and economical approach to control the rice planthoppers. However, up to date, few rice germplasm accessions that are resistant to the all three kinds of planthoppers (1) brown planthopper (BPH; Nilaparvata lugens Stål), (2) the small brown planthopper (SBPH; Laodelphax striatellus Fallen), and (3) the whitebacked planthopper (WBPH, Sogatella furcifera Horvath) have been identified; consequently, the genetic basis for host-plant broad spectrum resistance to rice planthoppers in a single variety has been seldom studied. Here, one wild species, Oryza officinalis (Acc. HY018, 2n = 24, CC), was detected showing resistance to the all three kinds of planthoppers. Because resistance to WBPH and BPH in O. officinalis has previously been reported, the study mainly focused on its SBPH resistance. The SBPH resistance gene(s) was (were) introduced into cultivated rice via asymmetric somatic hybridization. Three QTLs for SBPH resistance detected by the SSST method were mapped and confirmed on chromosomes 3, 7, and 12, respectively. The allelic/non-allelic relationship and relative map positions of the three kinds of planthopper resistance genes in O. officinalis show that the SBPH, WBPH, and BPH resistance genes in O. officinalis were governed by multiple genes, but not by any major gene. The data on the genetics of host-plant broad spectrum resistance to planthoppers in a single accession suggested that the most ideally practical and economical approach for rice breeders is to screen the sources of broad spectrum resistance to planthoppers, but not to employ broad spectrum resistance gene for the management of planthoppers. Pyramiding these genes in a variety can be an effective way for the management of planthoppers.

  8. Roseomonas oryzae sp. nov., isolated from paddy rhizosphere soil.

    Science.gov (United States)

    Ramaprasad, E V V; Sasikala, Ch; Ramana, Ch V

    2015-10-01

    A non-motile, coccus-shaped, pale-pink-pigmented bacterium, designated strain JC288T, was isolated from a paddy rhizosphere soil collected from Western Ghats, Kankumbi, Karnataka, India. Cells were found to be Gram-stain-negative, and catalase- and oxidase-positive; the major fatty acids were C16 : 0, C16 : 1ω7c/C16 : 1ω6c, C18 : 1ω7c/C18 : 1ω6c and C18 : 1 2-OH. The predominant respiratory quinone was Q-10 and the genomic DNA G+C content was 67.5 mol%. Strain JC288T contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, four unidentified aminolipids, three unidentified phospholipids, two unidentified lipids, an aminophospholipid and a glycolipid. Hydroxyspirilloxanthin was the major carotenoid of strain JC288T. 16S rRNA gene sequence comparisons indicated that strain JC288T represents a member of the genus Roseomonas within the family Acetobacteraceae of the phylum Proteobacteria. Strain JC288T shared the highest 16S rRNA gene sequence similarity with Roseomonas rhizosphaerae YW11T (97.3 %), Roseomonas aestuarii JC17T (97.1 %), Roseomonas cervicalis CIP 104027T (95.9 %) and other members of the genus Roseomonas ( < 95.5 %). The distinct genomic difference and morphological, physiological and chemotaxonomic differences from the previously described taxa support the classification of strain JC288T as a representative of a novel species of the genus Roseomonas, for which the name Roseomonas oryzae sp. nov. is proposed. The type strain is JC288T ( = KCTC 42542T = LMG 28711T).

  9. Serratia oryzae sp. nov., isolated from rice stems.

    Science.gov (United States)

    Zhang, Cai-Wen; Zhang, Jun; Zhao, Juan-Juan; Zhao, Xia; Zhao, Dong-Fang; Yin, Hua-Qun; Zhang, Xiao-Xia

    2017-08-01

    A novel endophytic bacterium, strain J11-6T, was isolated from rice stems. Its taxonomic position was investigated using a polyphasic approach. The novel strain was Gram-staining-negative, facultatively anaerobic, motile and rod-shaped. Although the results of phylogenetic analysis based on 16S rRNA gene sequences indicated that J11-6T represented a member of the genus Rahnella, multilocus sequence analysis (MLSA) on the basis of concatenated partial atpD, gyrB, rpoB and infB gene sequences showed a clear distinction of J11-6T from the type strains of species of the genus Rahnella but indicated that it lay within the clade of the genus Serratia. The phylogenetically closest species were Serratia fonticola and Serratia aquatilis on the basis of the results of the MLSA phylogenetic analysis. The predominant cellular fatty acids were C16 : 1ω7c (38.7 %) and C16 : 0 (25.0 %). The DNA G+C content was 53.2 mol%. The DNA-DNA relatedness was 17.4 % between J11-6T and Rahnella aquatilis CIP 78.65T, and 29.2 % between J11-6T and S. fonticola LMG 7882T which indicates that this strain represents a novel species of the genus Serratia. Characterization by genotypic and phenotypic analysis indicated that J11-6T (=ACCC 19934T=KCTC 52529T) represents a novel species of the genus Serratia, for which the name Serratia oryzae sp. nov. is proposed.

  10. Officially released mutant varieties in China

    International Nuclear Information System (INIS)

    Liu, L.; Van Zanten, L.; Shu, Q.Y.; Maluszynski, M.

    2004-01-01

    The use of mutation techniques for crop improvement in China has a long and well-established tradition of more than 50 years. As the result of intensive research in many institutes dealing with application of nuclear technologies more than 620 cultivars of 44 crop species have been released. Numerous mutant varieties have been grown on a large scale bringing significant economic impact, sustaining crop production and greatly contributing to increase of food production also in stress prone areas of the country. However, there is still missing information not only on the number of mutant varieties released in particular crop species but also on mutagens applied, selection approaches and on the use of mutants in cross breeding. Numerous Chinese scientists collected and systematized this information. Results of their work were often published in local scientific journals in the Chinese language and as such were unavailable to breeders from other countries. Having this in mind, we requested Dr. Liu Luxiang, the Director of the Department of Plant Mutation Breeding and Genetics, Institute for Application of Atomic Energy, Chinese Academy of Agricultural Sciences in Beijing to help us in finding as much information as possible on mutant varieties officially released in China. The data has been collected in close collaboration with his colleagues from various institutions all over the country and then evaluated, edited and prepared for publication by our team responsible for the FAO/IAEA Database of Officially Released Mutant Varieties. We would like to thank all Chinese colleagues who contributed to this list of Chinese mutant varieties. We hope that this publication will stimulate plant breeders in China to collect more information on released mutant varieties and especially on the use of mutated genes in cross breeding. (author)

  11. Development of high yielding mutants in lentil

    International Nuclear Information System (INIS)

    Rajput, M.A.; Sarwar, G.; Siddiqui, K.A.

    2001-01-01

    Full text: Lentil (Lens culinaris Medik.) locally known as Masoor, is the second most important rabi pulse crop, after chickpea, in Pakistan. It is cultivated on an area of over 63,400 ha, which constitutes about 4.83% of the total area under pulses. The annual production of the crop is 28,200 tones with an average yield of 445 kg/ha. Yield at the national level is very low, about one-half of the world's yield, which is mainly due to non-availability of high yield potential genotypes. Keeping in view the importance of mutants in developing a large number of new varieties, an induced mutations programme was initiated at AEARC, Tandojam during 1987-88, to develop high yielding varieties in lentil. For this, seeds of two lentil varieties, 'Masoor-85' and 'ICARDA-8' had been irradiated with gamma-rays ranging from 100-600 Gy in NIAB, Faisalabad during 1990. Selections were made in M2 on the basis of earliness, plant height, branches/plant and 100 grain weight. After confirming these mutants in M3 they were promoted in station yield trials and studied continuously for three consecutive years (1993- 1995). Overall results revealed that these mutants have consistent improvement of earliness in flowering and maturity. Plant height also increased in all mutant lines except AEL 23/40/91 where reduction in this attribute was observed as compared to parent variety. Mutant lines AEL 49/20/91 and AEL 13/30/91 showed improvement in 100 grain weight. The improvement of some agronomic characters enhanced the yield of mutant lines in comparison to parent varieties (Masoor-85 and ICARDA-8). The diversity in yield over the respective parents was computed from 6.94 to 60.12%. From these encouraging results it is hoped that mutant lines like AEL 12/30/91 and AEL 49/20/91 may serve as potential lentil genotypes in future. (author)

  12. A novel blast resistance gene, Pi54rh cloned from wild species of rice, Oryza rhizomatis confers broad spectrum resistance to Magnaporthe oryzae.

    Science.gov (United States)

    Das, Alok; Soubam, D; Singh, P K; Thakur, S; Singh, N K; Sharma, T R

    2012-06-01

    The dominant rice blast resistance gene, Pi54 confers resistance to Magnaporthe oryzae in different parts of India. In our effort to identify more effective forms of this gene, we isolated an orthologue of Pi54 named as Pi54rh from the blast-resistant wild species of rice, Oryza rhizomatis, using allele mining approach and validated by complementation. The Pi54rh belongs to CC-NBS-LRR family of disease resistance genes with a unique Zinc finger (C(3)H type) domain. The 1,447 bp Pi54rh transcript comprises of 101 bp 5'-UTR, 1,083 bp coding region and 263 bp 3'-UTR, driven by pathogen inducible promoter. We showed the extracellular localization of Pi54rh protein and the presence of glycosylation, myristoylation and phosphorylation sites which implicates its role in signal transduction process. This is in contrast to other blast resistance genes that are predicted to be intracellular NBS-LRR-type resistance proteins. The Pi54rh was found to express constitutively at basal level in the leaves, but upregulates 3.8-fold at 96 h post-inoculation with the pathogen. Functional validation of cloned Pi54rh gene using complementation test showed high degree of resistance to seven isolates of M. oryzae collected from different geographical locations of India. In this study, for the first time, we demonstrated that a rice blast resistance gene Pi54rh cloned from wild species of rice provides broad spectrum resistance to M. oryzae hence can be used in rice improvement breeding programme.

  13. Efectividad biológica delazoxystrobin para el control de pyricularia oryzae cav. y cercospora oryzae miyake. en arroz de temporal en Veracruz, México

    Directory of Open Access Journals (Sweden)

    Enrique Becerra

    2001-01-01

    Full Text Available El estado de Veracruz, México, siembra anualmente 22000 ha de arroz de temporal con un rendimiento medio de 3,5 t/ha, debido principalmente a problemas de sequía lo cual favorece la presencia de hongos como Pyricularia oryzae Cav. (quema del arroz y Cercospora oryzae Miyake. (Mancha angosta. Con el objeto de conocer el comportamiento de nuevos fungicidas se evaluó la eficacia del Azoxystrobin en el control de estos hongos. El experimento se estableció en el municipio de Tres Valles, Veracruz, durante el temporal de 1999, con semilla de Milagro Filipino Depurado. El diseño estadístico utilizado fue bloques al azar con cuatro repeticiones. Los tratamientos evaluados fueron: Azoxystrobin a 0,2, 0,4 y 0,6 l/ha vs Tecto60 a 0,5 kg/ha y un testigo sin aplicación. Estos fueron aplicados al presentarse los primeros síntomas de las enfermedades. Se evaluó la incidencia, número de lesiones en 20 plantas, índice de intensidad, el rendimiento de grano y fitotoxicidad. Se encontró que el Azoxystrobin obtuvo mejores resultados que el Tecto 60 y éste a su vez que el testigo no tratado. El mejor control para P. oryzae y C. oryzae y el mayor rendimiento de grano (4432 kg/ha se logró cuando se aplicó Azoxystrobin en dosis de 0,6 l/ha, aunque con 0,2 y 0,4 l/ha de este fungicida tuvo un buen control de estas enfermedades. Ninguno de los fungicidas causó toxicidad al arroz

  14. Occurrence of fungus Rhizopus sp in bioassays with Allium cepa germinated in the presence of uranium to study the effect of natural radioactivity

    Energy Technology Data Exchange (ETDEWEB)

    Xavier, Magno N.; Oliveira, Andressa L.; Maffei, Eliane M.D.; Campos, Simara S., E-mail: simaracampos@gmail.com [Universidade Estadual do Sudoeste da Bahia (UESB), Vitoria da Conquista, BA (Brazil). Departamento de Ciencias Exatas e Tecnologicas; Gennari, Roseli F. [Universidade de Sao Paulo (USP), SP (Brazil). Instituto de Fisica. Departamento de Fisica Nuclear

    2015-07-01

    The demographic and global economic growth has promoted increasing power consumption. In this context, several studies point to nuclear energy as being promising to meet such demand. Although Brazil composes the seventh position in the world ranking of uranium reserves, the ore is still little explored in Brazil, considering its vast existing arsenal. On the one hand, despite nuclear energy has brought great benefits, technological and socio-economic development, it generates controversy about environmental contamination and risks to public health. Studies on this subject indicate that areas where uranium ore concentration is high, natural environmental radiation exposure levels are already higher than in other regions. The aim of this study is to observe the simple germination of the bio-indicator (Allium cepa), typically used to assess potential chromosomal aberrations, suffer any adverse effect caused by natural radiation uranium. The choice of this bio-indicator is based on its potential for evaluating the mutation caused by countless chemical compounds. Four treatments with three replicates were designed. In each treatment, 10 seeds of onion A. cepa without any pesticides were packed in the Petri dish lined with germination paper and room temperature (25°C) was kept until the root reaches approximately 1cm long. As a result, growth of the fungus Rhizopus sp was observed, in the experiments where uranium ore was added. It is important to mention according to the literature, this fungus can cause serious infections (and often fatal) in humans and animals, due to its high growth rate and also to their ability on surviving in relatively high temperatures. (author)

  15. Occurrence of fungus Rhizopus sp in bioassays with Allium cepa germinated in the presence of uranium to study the effect of natural radioactivity

    International Nuclear Information System (INIS)

    Xavier, Magno N.; Oliveira, Andressa L.; Maffei, Eliane M.D.; Campos, Simara S.; Gennari, Roseli F.

    2015-01-01

    The demographic and global economic growth has promoted increasing power consumption. In this context, several studies point to nuclear energy as being promising to meet such demand. Although Brazil composes the seventh position in the world ranking of uranium reserves, the ore is still little explored in Brazil, considering its vast existing arsenal. On the one hand, despite nuclear energy has brought great benefits, technological and socio-economic development, it generates controversy about environmental contamination and risks to public health. Studies on this subject indicate that areas where uranium ore concentration is high, natural environmental radiation exposure levels are already higher than in other regions. The aim of this study is to observe the simple germination of the bio-indicator (Allium cepa), typically used to assess potential chromosomal aberrations, suffer any adverse effect caused by natural radiation uranium. The choice of this bio-indicator is based on its potential for evaluating the mutation caused by countless chemical compounds. Four treatments with three replicates were designed. In each treatment, 10 seeds of onion A. cepa without any pesticides were packed in the Petri dish lined with germination paper and room temperature (25°C) was kept until the root reaches approximately 1cm long. As a result, growth of the fungus Rhizopus sp was observed, in the experiments where uranium ore was added. It is important to mention according to the literature, this fungus can cause serious infections (and often fatal) in humans and animals, due to its high growth rate and also to their ability on surviving in relatively high temperatures. (author)

  16. Effect of hydrolysis enzymatic process of corn using protease crude (Rhizopus oligosporus-C1) to produce corn hydrolisate rich folic acid

    Science.gov (United States)

    Maryati, Yati; Susilowati, Agustine; Melanie, Hakiki; Lotulung, Puspa D.

    2017-11-01

    Corn hydrolyzate (Zea mays L) as a functional food fortificant derived from natural folic acid has been evaluated through a hydrolysis process using protease enzyme Rhizopus oligosporus strain C1. Enzymatic hydrolysis was carried out on two types of corn; yellow and white pearl variety corn, at concentration of protease enzyme (rough) 0.025; 0.125; and 0.225% (v/w of soluble nixtamal corn protein) with a hydrolysis time of 24 h at 30 °C, and pH 5.0. The results showed that the concentration of protease enzymes can increase the folic acid to the optimum condition, from the beginning to the end of the process time. Folic acid optimization of hydrolysis results in each corn was at the concentration of protease enzyme 0.225% (v/w of soluble nixtamal corn protein) in white corn and yellow corn at 24 hours hydrolysis, with folic acid composition, 283.56 µg/mL and 412.52 µg/mL, 1.07 and 1.04 mg/mL of soluble proteins, proteolytic activity 2.09 and 2.06 U/mL, total solids of 21.74 and 17.85%, total sugars of 0.56 and 2.22 mg/mL, and reducing sugar 91.72 and 48.47 mg/mL. In this condition, the increase of optimum folic acid for white corn was 33.57% and for yellow corn was 71.60% after hydrolysis.

  17. Characterization of a Thermotolerant Phytase Produced by Rhizopus microsporus var. microsporus Biofilm on an Inert Support Using Sugarcane Bagasse as Carbon Source.

    Science.gov (United States)

    Sato, Vanessa Sayuri; Jorge, João Atílio; Guimarães, Luis Henrique Souza

    2016-06-01

    The Rhizopus microsporus var. microsporus biofilm was able to produce increased levels of an extracellular thermotolerant phytase using polyethylene and viscose as an inert support in both modified NBRIP medium and modified Khanna medium containing sugarcane bagasse as the carbon source. The enzyme production was strictly regulated by the phosphorus content with optimal production at 0.5 mM of sodium phytate and KH2PO4. The extracellular phytase, RMPhy1, was purified 4.18-fold with 4.78 % recovery using DEAE-cellulose and CM-cellulose. A single protein band with a molecular mass of 35.4 kDa was obtained when the samples were subjected to 10 % SDS-PAGE. The optimum temperature for activity was 55 °C and the optimum pH was 4.5. R. microsporus var. microsporus phytase exhibited high stability at 30 and 40 °C with a half-life of 115 min at 60 °C. The enzyme activity increased in the presence of Ca (2+) and was inhibited by Zn(2+), arsenate, and sodium phosphate. Phytase demonstrated high substrate specificity for sodium phytate with K m = 0.72 mM and V max = 94.55 U/mg of protein and for p-NPP with K m = 0.04 mM and V max = 106.38 U/mg of protein. The enzyme also hydrolyzed ATP, AMPc, glucose 6-phosphate, glucose 1-phosphate, and UDPG. This is the first report on phytase characterization delivered with biofilm technology. The properties of the enzyme account for its high potential for use in biotechnology and the possibility of application in different industrial sectors as feed in the future.

  18. Penetration Peg Formation and Invasive Hyphae Development Require Stage-Specific Activation of MoGTI1 in Magnaporthe oryzae.

    Science.gov (United States)

    Li, Yang; Wang, Guanghui; Xu, Jin-Rong; Jiang, Cong

    2016-01-01

    The hemibiotrophic pathogen Magnaporthe oryzae causes one of the most destructive diseases in cultivated rice. Complex infection-related morphogenesis and production of various effectors are known to be important for successful colonization and disease development. In this study, we characterized the activation of the MoGTI1 transcription factor and its role in infection-related morphogenesis and effector gene expression. The Mogti1 mutant was nonpathogenic, although it was normal in appressorium formation and turgor generation. Close examination showed that Mogti1 was defective in penetration and growth of normal invasive hyphae. Deletion of MoGTI1 affected the expression of the majority of effector genes. The expression of MoGti1 appeared to be controlled by the Mps1 but not Pmk1 mitogen-activated protein kinase (MAPK), and the mps1 and Mogti1 mutants had similar phenotypes in plant infection and cell wall integrity defects. However, lack of MAPK phosphorylation sites and dispensability of the putative MAPK docking site suggested that MoGti1 is not a direct target of Mps1. Site-specific mutagenesis analyses showed that the putative protein kinase A phosphorylation site was not essential for localization of MoGti1 to the nucleus but important for its normal function. Although the cyclin-dependent kinase (CDK) phosphorylation site of MoGti1 is dispensable during vegetative growth and appressorium formation, the S77A mutation affected penetration and invasive growth. Localization of MoGti1(S77A)-green fluorescent protein to the nucleus in late stages of appressorium formation and during invasive growth was not observed, suggesting a stage-specific CDK phosphorylation of MoGti1. Overall, our data indicate that Mps1 may indirectly regulate the expression of MoGti1 in maintaining cell wall integrity, conidiation, and plant infection. MoGti1 is likely a stage-specific target of CDK and plays a crucial role in effector gene expression and morphogenesis related to the

  19. Rice is the seed of the monocot plants Oryza sativa (Asian rice) or ...

    African Journals Online (AJOL)

    BIOTECH

    2013-10-16

    Oct 16, 2013 ... of culture. The regenerated plantlets were transferred to pots for acclimatization. About 80% of plants were survived in the greenhouse condition. Key words: Somatic embryogenesis, immature zygotic embryos, Indica rice, plant regeneration. INTRODUCTION. Rice (Oryza sativa L.) is one of the most ...

  20. Basil oil fumigation increases radiation sensitivity in adult Sitophilus oryzae (Coleoptera: Curculionidae).

    Science.gov (United States)

    The biological activity of basil (Ocimum basilicum L.) oil was tested against the stored product pest rice weevil, Sitophilus oryzae(L.). Adult weevils were exposed to seven different concentrations of basil oil ranging from 0.12 µl/ml-0.60 µl/ml in Petri dishes and mortality was assessed at 3,4 and...

  1. Genetic diversity associated with conservation of endangered Dongxiang wild rice (Oryza rufipogon)

    Science.gov (United States)

    The wild progenitor species (Oryza rufipogon) of Asian cultivated rice (O. sativa) is located in Dongxiang county, China where it is considered the northernmost range worldwide. Nine ex situ and three in situ populations of the Dongxiang wild rice (DXWR) and four groups of modern cultivars were geno...

  2. Construction of six Oryza sativa x O. rufipogon Chromosome Segment Substitution Line (CSSL) Libraries

    Science.gov (United States)

    Transgressive variation has been observed in rice (Oryza sativa) as an increase in grain yield and attributed to the ancestral parent, O. rufipogon, in mapping populations developed from several adapted rice varieties crossed with a single O. rufipogon accession. To explore this phenomenon of transg...

  3. Induction of salicylic acid-mediated defense response in perennial ryegrass against infection by Magnaporthe oryzae.

    Science.gov (United States)

    Rahman, Alamgir; Kuldau, Gretchen A; Uddin, Wakar

    2014-06-01

    Incorporation of plant defense activators is an innovative approach to development of an integrated strategy for the management of turfgrass diseases. The effects of salicylic acid (SA), benzothiadiazole (BTH, chemical analog of SA), jasmonic acid (JA), and ethephon (ET, an ethylene-releasing compound) on development of gray leaf spot in perennial ryegrass (Lolium perenne L.) caused by Magnaporthe oryzae were evaluated. Gray leaf spot disease incidence and severity were significantly decreased when plants were treated prior to inoculation with SA, BTH, and partially by ET but not by JA. Accumulation of endogenous SA and elevated expression of pathogenesis-related (PR)-1, PR-3.1, and PR-5 genes were associated with inoculation of plants by M. oryzae. Treatment of plants with SA enhanced expression levels of PR-3.1 and PR-5 but did not affect the PR-1 level, whereas BTH treatment enhanced relative expression levels of all three PR genes. Microscopic observations of leaves inoculated with M. oryzae revealed higher frequencies of callose deposition at the penetration sites in SA- and BTH-treated plants compared with the control plants (treated with water). These results suggest that early and higher induction of these genes by systemic resistance inducers may provide perennial ryegrass with a substantial advantage to defend against infection by M. oryzae.

  4. Identification of molecular markers linked to rice bacterial blight resistance genes from Oryza meyeriana

    Directory of Open Access Journals (Sweden)

    Jing WANG,Chen CHENG,Yanru ZHOU,Yong YANG,Qiong MEI,Junmin LI,Ye CHENG,Chengqi YAN,Jianping CHEN

    2015-09-01

    Full Text Available Y73 is a progeny of asymmetric somatic hybridization between Oryza sativa cv. Dalixiang and the wild rice species Oryza meyeriana. Inoculation with a range of strains of Xanthomonas oryzae pv. oryzae showed that Y73 had inherited a high level of resistance to rice bacterial blight (BB from its wild parent. An F2 population of 7125 individuals was constructed from the cross between Y73 and a BB-susceptible cultivar IR24. After testing 615 SSR and STS markers covering the 12 rice chromosomes, 186 markers were selected that showed polymorphism between Y73 and IR24. Molecular markers linked to the BB resistance genes in Y73 were scanned using the F2 population and the polymorphic markers. The SSR marker RM128 on chromosome 1, the STS marker R03D159 on chromosome 3 and the STS marker R05D104 on chromosome 5 were found to be linked to the rice BB resistance genes in Y73.

  5. Can rice (Oryza sativa) mitigate pesticides and nutrients in agricultural runoff?

    Science.gov (United States)

    Phytoremediation of nutrients and pesticides in runoff is a growing conservation effort, particularly in agriculturally intensive areas such as the lower Mississippi River Valley. In the current study, rice (Oryza sativa) was examined for its mitigation capacity of nitrogen, phosphorus, diazinon, a...

  6. Growth responses of NaCl stressed rice (Oryza sativa L.) plants ...

    African Journals Online (AJOL)

    GREGORY

    2010-09-27

    Sep 27, 2010 ... Growth responses of NaCl stressed rice (Oryza sativa. L.) plants ... 2008), which is a real threat to human's food security. Existed situation may ..... content and composition of essential oil and minerals in black cumin. (Nigella ...

  7. Analysis of the temporal variation of radiation balance components in arid rice (Oryza sativa L.) culture

    International Nuclear Information System (INIS)

    Prates, J.E.; Coelho, D.T.; Steinmetz, S.

    1988-01-01

    The time variation of measured radiation balance components in a cultived rice area (Oryza sativa L.) under arid conditions in the Brazil central-west region was analysed. The relation between global solar radiation, radiation balance, reflected radiation and terrestrial effective radiation in three different stages of the culture development: vegetative stage; blooming and maturation, was determined. (M.C.K.) [pt

  8. Toxic effects of essential plant oils in adult Sitophilus oryzae (Linnaeus (Coleoptera, Curculionidae

    Directory of Open Access Journals (Sweden)

    Andréa Roveré Franz

    2011-03-01

    Full Text Available Toxic effects of essential plant oils in adult Sitophilus oryzae (Linnaeus (Coleoptera, Curculionidae. Stored grains are subject to losses in quality nutritional value and in sanitation from the time they are stored to the time they are consumed. Botanical insecticides may offer an alternative solution for pest control. The objective was to test the insecticidal properties of the essential oils of Cymbopogon citratus (leaf, Zingiber officinale (root and Mentha sp. (leaf. The efficacy of these oils was tested to control the rice weevil, S. oryzae, using hydrodistillation. Chemical analysis of the essential oils was carried out by gas chromatography. Major components of C. citratus were geranial (48% and neral (31%, of Z. officinale were α-zingibereno (13%, geranial (16%, neral (10% and α-farneseno (5% and of Mentha sp. was menthol (92%. Bioassays were carried out by fumigation and topical application. In topical application assays, the essential oil of C. citratus had greater toxicity (LC50 0.027 µL mL-1 and shorter exposure time than the oils of the other two plants. After 24 h and 48 h, 70% and 100% mortality of S. oryzae occurred, respectively. In fumigation assays, essential oil of Z. officinale had a lower LC50 (1.18 µL cm-2 and 70% mortality after 24 h exposure. Therefore, we recommend the use of essential oils of C. citratus and Z. officinale to control the rice weevil S. oryzae.

  9. Some factors affecting reproduction in the Rice weevil Sitophilus Oryzae (L.)

    International Nuclear Information System (INIS)

    Hasaballa, Z.A.; Abdelkawy, F.K.

    1992-01-01

    Laboratory investigations on the effects or radiation, type of food and population density on the reproductive potential of the rice weevil. Sitophilus Oryzae were conducted at 30 degree C. and 75% R.H. The results indicate that the survival number of adult weevils infesting wheat grains increased markedly after 45 and 90 days of infestation. The survival and reproductive potential of the rice weevils declined significantly after exposure to gamma rays. This decline was more pronounced after 90 days and appeared to be markedly dose dependent. It was noticed that the rate of reproduction of the rice weevils was greatly influenced by insect crowding, science adults of S. Oryzae reared under crowded conditions failed to increase in numbers for 3 months as was expected. The reproduction of S. Oryzae was affected by the type of food. Wheat grains were more suitable than rice and maize grains as the average survival numbers of S. Oryzae reared on wheat grains were more after 45 and 90 days than those reared on rice and maize grains.3 tab

  10. A New Eudesmane Sesquiterpene from Nigrospora oryzae, an Endophytic Fungus of Aquilaria sinensis

    Directory of Open Access Journals (Sweden)

    Dongli Li

    2014-07-01

    Full Text Available A new eudesmane-type sesquiterpene, 11 -hydroxy capitulatin B (1 , along with a known related sesquiterpene, capitulatin B (2, was isolated from the endophytic fungus Nigrospora oryzae A8 from Aquilaria sinensis, the only plant resource for agarwood production in China. This research demonstrates that the endophytic fungi from A. sinensis might play a role in the formation of agarwood.

  11. An ecogeographic analysis of Oryza series Sativae in Asia and the Pacific

    NARCIS (Netherlands)

    Banaticla-Hilario, M.C.N.

    2012-01-01

    The non-cultivated speciesof the genus Oryza can provide a genetic arsenal of useful traits for improving the widely cultivated and consumed Asian rice (O. sativa). The diversity of these valuable plant resources must be well understood to ensure their effective in- and ex-situ

  12. Early detection of airborne inoculum of Magnaporthe oryzae in turfgrass fields using a quantitative LAMP assay

    Science.gov (United States)

    Gray leaf spot (GLS) is a destructive disease of perennial ryegrass caused by a host specific pathotype of the ascomycete Magnaporthe oryzae. Early diagnosis is crucial for effective disease management and the implementation of Integrated Pest Management practices. However, a rapid diagnostic protoc...

  13. Transcriptome Analysis of Early Responsive Genes in Rice during Magnaporthe oryzae Infection

    Directory of Open Access Journals (Sweden)

    Yiming Wang

    2014-12-01

    Full Text Available Rice blast disease caused by Magnaporthe oryzae is one of the most serious diseases of cultivated rice (Oryza sativa L. in most rice-growing regions of the world. In order to investigate early response genes in rice, we utilized the transcriptome analysis approach using a 300 K tilling microarray to rice leaves infected with compatible and incompatible M. oryzae strains. Prior to the microarray experiment, total RNA was validated by measuring the differential expression of rice defense-related marker genes (chitinase 2, barwin, PBZ1, and PR-10 by RT-PCR, and phytoalexins (sakuranetin and momilactone A with HPLC. Microarray analysis revealed that 231 genes were up-regulated (>2 fold change, p < 0.05 in the incompatible interaction compared to the compatible one. Highly expressed genes were functionally characterized into metabolic processes and oxidation-reduction categories. The oxidative stress response was induced in both early and later infection stages. Biotic stress overview from MapMan analysis revealed that the phytohormone ethylene as well as signaling molecules jasmonic acid and salicylic acid is important for defense gene regulation. WRKY and Myb transcription factors were also involved in signal transduction processes. Additionally, receptor-like kinases were more likely associated with the defense response, and their expression patterns were validated by RT-PCR. Our results suggest that candidate genes, including receptor-like protein kinases, may play a key role in disease resistance against M. oryzae attack.

  14. Gamma radiation effects on rice, substrate for Sitophilus oryzae (L.) rearing

    International Nuclear Information System (INIS)

    Wiendl, F.M.; Arthur, V.; Walder, J.M.M.; Domarco, R.E.

    1987-01-01

    The gamma radiation effects (800 Krad, 60 Co) on rice are studied. Degraded substances by the radiation and how this degradation affects the biology of Sitophilus oryzae (L.) are searched. The vitamins, proteins and stard of the rice are affected by the radiation. (M.A.C.) [pt

  15. Metabolic engineering of the morphology of Aspergillus oryzae by altering chitin synthesis

    DEFF Research Database (Denmark)

    Muller, C.; Mcintyre, Mhairi; Hansen, Kim

    2002-01-01

    Morphology and alpha-amylase production during submerged cultivation were examined in a wild-type strain (A1560) and in strains of Aspergillus oryzae in which chitin synthase B (chsB) and chitin synthesis myosin A (csmA) have been disrupted (ChsB/G and CM101). In a flowthrough cell, the growth...

  16. What Does Genetic Diversity of Aspergillus flavus Tell Us About Aspergillus oryzae?

    Science.gov (United States)

    Aspergillus flavus and Aspergillus oryzae belong to Aspergillus section Flavi. They are closely related and are of significant economic importance. The former species has the ability to produce harmful aflatoxins while the latter is widely used in food fermentation and industrial enzyme production. ...

  17. Measurement and analysis on optical characteristics of Aspergillus oryzae spores in infrared band

    Science.gov (United States)

    Li, Le; Hu, Yihua; Gu, Youlin; Chen, Wei; Xu, Shilong; Zhao, Xinying

    2015-10-01

    Spore is an important part of bioaerosols. The optical characteristics of spore is a crucial parameter for study on bioaerosols. The reflection within the waveband of 2.5 to15μm were measured by squash method. Based on the measured data, Complex refractive index of Aspergillus oryzae spores within the waveband of 3 to 5μm and 8 to 14 μm were calculated by using Krames-Kronig (K-K) relationship. Then,the mass extinction coefficient of Aspergillus oryzae spores within the waveband of 3 to 5μm and 8 to 14μm were obtained by utilizing Mie scattering theory, and the results were analyzed and discussed. The average mass extinction coefficient of Aspergillus oryzae spores is 0.51 m2/g in the range of 3 to 5μm and 0.48m2/g in the range of 8 to 14μm. Compared with common inorganic compounds, Aspergillus oryzae spores possesses a good extinction performance in infrared band.

  18. Polyol accumulation by Aspergillus oryzae at low water activity in solid-state fermentation

    NARCIS (Netherlands)

    Ruijter, G.J.G.; Visser, J.; Rinzema, A.

    2004-01-01

    Polyol accumulation and metabolism were examined in Aspergillus oryzae cultured on whole wheat grains or on wheat dough as a model for solid-state culture. In solid-state fermentation (SSF), water activity (a(w)) is typically low resulting in osmotic stress. In addition to a high level of mannitol,

  19. Purification and properties of amylolytic enzyme from Aspergillus oryzae MIBA316

    OpenAIRE

    仮屋, 麻紀子; 矢野, めぐむ; 瀧井, 幸男; Makiko, Kariya; Megumu, Yano; Yukio, Takii

    2003-01-01

    Amylolytic enzyme was purified to electrophoretically homogeneous state from culture broth of Aspergillus oryzae MIBA316. This enzyme hydrolyzed preferentially amylopectin, starch and glycogen. Approaches to complete breakdown of starch to its components and their utilization in food processing were discussed.

  20. Genotype × environment interactions of yield traits in backcross introgression lines derived from Oryza sativa cv. Swarna /Oryza nivara

    Directory of Open Access Journals (Sweden)

    Divya Balakrishnan

    2016-10-01

    Full Text Available Advanced backcross introgression lines (BILs developed from crosses of Oryza sativa var. Swarna/O. nivara accessions were grown and evaluated for yield and related traits. Trials were conducted for consecutive three seasons in field conditions in a randomized complete block design with three replications. Data on yield traits under irrigated conditions were analyzed using the Additive Main Effect and Multiplicative Interaction (AMMI, Genotype and Genotype × Environment Interaction (GGE and modified rank-sum statistic (YSi for yield stability. BILs viz., G3 (14S and G6 (166S showed yield stability across the seasons along with high mean yield performance. G3 is early in flowering with high yield and has good grain quality and medium height, hence could be recommended for most of the irrigated locations. G6 is a late duration genotype, with strong culm strength, high grain number and panicle weight. G6 has higher yield and stability than Swarna but has Swarna grain type. Among the varieties tested DRRDhan 40 and recurrent parent Swarna showed stability for yield traits across the seasons. The component traits thousand grain weight, panicle weight, panicle length, grain number and plant height explained highest genotypic percentage over environment and interaction factors and can be prioritized to dissect stable QTLs/ genes. These lines were genotyped using microsatellite markers covering the entire rice genome and also using a set of markers linked to previously reported yield QTLs. It was observed that wild derived lines with more than 70% of recurrent parent genome were stable and showed enhanced yield levels compared to genotypes with higher donor genome introgressions.