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Sample records for fungus magnaporthe grisea

  1. A Lipoxygenase Pathway Is Activated in Rice after Infection with the Rice Blast Fungus Magnaporthe grisea.

    Science.gov (United States)

    Ohta, H; Shida, K; Peng, Y L; Furusawa, I; Shishiyama, J; Aibara, S; Morita, Y

    1991-09-01

    Lipoxygenase (LOX) and lipid hydroperoxide-decomposing activity (LHDA) markedly increased in the fifth leaves of rice (Oryza sativa cv Aichiasahi) after infection with the rice blast fungus, Magnaporthe grisea. The increases in the enzyme activities were significantly higher in response to infection with an incompatible strain (race 131) compared with infection with a compatible strain (race 007) of the fungus. Using ion-exchange chromatography, we isolated three LOX activities (leaf LOX-1, -2, -3) from both uninoculated and infected leaves. The activity of leaf LOX-3, in particular, increased in the incompatible race-infected leaves. The leaf LOX-3 had a pH optimum of 5.0 and produced preferentially 13-l-hydroperoxy-9,11 (Z,E)-octadecadienoic acid (13-HPODD) from linoleic acid. 13-HPODD and 13-l-hydroxy-9,11 (Z,E)-octadecadienoic acid, one of the reaction products from 13-HPODD by LHDA, were highly inhibitory to the germination of conidia of the fungus. The present study provides correlative evidence for important roles of LOX and LHDA in the resistance response of rice against the blast fungus.

  2. Variation in virulence in the rice blast fungus Magnaporthe grisea in São Paulo State

    Directory of Open Access Journals (Sweden)

    Urashima Alfredo Seiiti

    2002-01-01

    Full Text Available Resistant varieties have been the preferred means to control Magnaporthe grisea, the causal organism of the rice blast disease. The objective of this study was to examine the degree of diversity of the pathogen in different rice growing regions of São Paulo State, Brazil. Blast samples collected from rice varieties in three different regions (Tremembé, Mococa and José Bonifácio were analyzed for race structure employing the Japanese rice differentials. The highest degree of virulence diversity was observed in Tremembé with 22 different races in three different varieties. Furthermore, no resistance gene in the Japanese differentials was effective to all isolates of M. grisea from São Paulo State.

  3. Promoter trapping in Magnaporthe grisea

    Institute of Scientific and Technical Information of China (English)

    LIU Xiao-hong; LU Jian-ping; WANG Jiao-yu; MIN Hang; LIN Fu-cheng

    2006-01-01

    Application of promoter trapping based on transformation in Magnaporthe grisea is reported in this paper. Two promoter-trapping vectors, designated as pCBGFP and pEGFPHPH, were constructed and transformed into protoplasts of M.grisea. A library of 1077 transformants resistant to hygromycin B was generated. Of which, 448 transformants were found to express eGFP gene in different structures ofM. grisea. Three transformants grew slowly, 5 transformants decreased in conidiafion and 7 transformants reduced in pathogenicity greatly among these 448 transformants. Eleven transformants were checked by genomic southern blot randomly, and 9 of which were single-copy insertions. The promoter trapping technique has been applied successfully in M. grisea and can be used as a tool for functional genomic analysis.

  4. Representative appressorium stage eDNA library of Magnaporthe grisea

    Institute of Scientific and Technical Information of China (English)

    LU Jian-ping; LIU Tong-bao; YU Xiao-yun; LIN Fu-cheng

    2005-01-01

    A mature appressorium cDNA library of rice blast fungus, Magnaporthe grisea, was constructed in a ?TriplEx2 vector by SMARTTM cDNA library containing 2.37?106 independent clones about 100% of which harbor foreign cDNA inserts with average size of 660 bp. Of 9 randomly selected clones, 2 expressed sequence tags (ESTs) sequences did not have homologous EST sequences of M. grisea in GenBank. The appressorium cDNA library is suitable for gene expression analysis and function analysis of the late stages of appressorium formation and the early stages of penetration of M. grisea.

  5. Geographic Distribution of Mating Types in Magnaporthe grisea and the Relationship Between Fertile Isolates in China

    Institute of Scientific and Technical Information of China (English)

    SHEN Ying; Notteghem Jean Loup.; Milazzo Joёlle.; YUAN Xiao-ping; Adreit Henry; ZHAO Xin-hua; WANG Yan-li; Tharreau Didier.

    2002-01-01

    377 isolates of Magnaporthe grisea were collected from 17 provinces in China and their geographic distribution of mating types and their fertility was tested with four standard isolates, KA3 and TH12 (Mat1.1) and Guy11 and TH16 (Mat1.2) provided by CIRAD. 73 fertile isolates were tested with SCAR markers of 13 pairs of primers. Preliminary results showed that the geographic distribution of M. grisea existed among isolates collected from the same location as well as different locations and the genetic relationship between fertile isolates of the fungus in China. The existence of sexual reproduction of M. grisea was explored in the field as well.

  6. Cloning, sequencing and expression analysis of the NAR promoter activated during hyphal stage of Magnaporthe grisea

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The promoter of N4R gene in Magnaporthe grisea was isolated and sequenced. The promoter sequences contained the "TATA" box, the "CAAT" box, and binding sites for fungal regulatory proteins. Programs that predict promoter sequences indicated that promoter sequence lies between locations 430 and 857 of the NAR promoter fragment. GFP expression under the NAR promoter and NAR transcript analysis revealed that this promoter is activated primarily at the mycelial stage in the rice blast fungus and could be used to express native or extrinsic genes in the mycelia of the rice blast fungus.

  7. Screening and identification of mutants of Magnaporthe grisea by REMI

    Institute of Scientific and Technical Information of China (English)

    XIONG Ruyi; LIU Juan; ZHOU Yijun; FAN Yongjian; ZHENG Xiaobo

    2007-01-01

    The plasmid pUCATPH was used to establish a transformation system in wild-type isolate M131 of Magnaporthe grisea.Six hundred and thirty-nine transformants were obtained by restriction enzyme-mediated integration (REMI) with hygromycin B (hyg B) resistance as a tag.Morphological analysis of two of the REMI mutants confirmed that they produced little melanin under black light and continued for three generations.Pathogenicity identification of six mutants screened proved that they made pathogenicity changes on three sets of differential varieties with different resistance genes.Rep-PCR analyses showed that two morphological mutants and two pathogenicity mutants differed from wild-type isolate M131 at the molecular level.RFLP analyses were performed to study the four mutants at the molecular level and the integration sites of the plasmid DNA.The results showed that the plasmid was inserted into all four mutants and that the insertion sites were random.

  8. Isolamento e regeneração de protoplastos de Magnaporthe grisea Isolation and regeneration of Magnaporthe grisea protoplasts

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Marchi

    2006-09-01

    Full Text Available Protoplastos são ferramentas biológicas importantes para pesquisas em fungos filamentosos, sendo empregados intensamente em transformação genética. O isolamento de protoplastos de Magnaporthe grisea foi facilitado com Novozym 234, contudo, este complexo enzimático encontra-se indisponível no mercado. Assim, objetivou-se comparar a eficiência de enzimas líticas disponíveis comercialmente na obtenção de protoplastos de M. grisea. Paralelamente, analisaram-se estabilizadores osmóticos, tempos de digestão e freqüência de regeneração. Maior produção de protoplastos foi obtida com o uso simultâneo de Lysing Enzymes e Cellulase Onozuka R-10. O uso de 10 ou 15 mg de cada complexo enzimático, em 3 mL de estabilizador osmótico, resultou em maior liberação de protoplastos. O melhor estabilizador osmótico foi MgSO4 1,2 M / NaH2PO4 0,01 M, pH 5,8, seguido por MgSO4 0,8 M / NaH2PO4 0,01 M, pH 5,8. O isolamento de protoplastos foi monitorado a cada 60 minutos, atingindo o máximo após incubação por 3 a 6 horas. No entanto, maior freqüência de regeneração (19,4% foi registrada para protoplastos obtidos após 3 horas de hidrólise enzimática.Protoplasts are important biological tools in filamentous fungi research. Fungal protoplasts have been extensively used in experiments with genetic transformation. Protoplastization of Magnaporthe grisea was accomplished with Novozym 234, however, this enzymatic complex is no commercially available for purchase. Thus, the efficiency of several other commercial enzymes in M. grisea protoplasts preparation was investigated. At the same time, osmotic buffer, digestion time and regeneration rate were also analyzed. The highest protoplasts production was obtained with Lysing Enzymes plus Cellulase Onozuka R-10. The use of 10 or 15 mg of each enzymatic complex in 3 mL of osmotic buffer was most effective for the protoplasts yields. The best osmotic buffer was MgSO4 1.2 M / NaH2PO4 0.01 M, pH 5

  9. Phytochromes Regulate SA and JA Signaling Pathways in Rice and Are Required for Developmentally Controlled Resistance to Magnaporthe grisea

    Institute of Scientific and Technical Information of China (English)

    Xian-Zhi Xie; Yan-Jiu Xue; Jin-Jun Zhoua; Bin Zhang; Hong Chang; Makoto Takano

    2011-01-01

    Old leaves of wild-type rice plants (Oryza sativa L. Cv. Nipponbare)are more resistant to blast fungus (Mag-naporthe grisea)than new leaves. In contrast, both old and new leaves of the rice phytochrome triple mutant (phyAphyB-phyC)are susceptible to blast fungus. We demonstrate that pathogenesis-related class 1 (PR1)proteins are rapidly and strongly induced during M. Grisea infection and following exogenous jasmonate (JA)or salicylic acid (SA)exposure in the old leaves, but not in the new leaves of the wild-type. In contrast, the accumulation of PR1 proteins was significantly attenuated in old and new leaves of the phyAphyBphyC mutant. These results suggest that phytochromes are required for the induction of PR1 proteins in rice. Basal transcription levels of Prla and PRlb were substantially higher in the wild-type as compared to the phyAphyBphyC mutant, suggesting that phytochromes also are required for basal expression of PR1 genes. Moreover, the transcript levels of genes known to function in SA-or JA-dependent defense pathways were regulated by leaf age and functional phytochromes. Taken together, our findings demonstrate that phytochromes are required in rice for age-related resistance to M, grisea and may indirectly increase PR1 gene expression by regulating SA-and JA-dependent defense pathways.

  10. Biosynthesis of UDP-4-keto-6-deoxyglucose and UDP-rhamnose in pathogenic fungi Magnaporthe grisea and Botryotinia fuckeliana

    National Research Council Canada - National Science Library

    Martinez, Viviana; Ingwers, Miles; Smith, James; Glushka, John; Yang, Ting; Bar-Peled, Maor

    2012-01-01

    .... Nevertheless, little is known about the pathways for the synthesis of these glycans. We show that rhamnose is present in glycans isolated from the rice pathogen Magnaporthe grisea and from the plant pathogen Botryotinia fuckeliana...

  11. Isolamento e regeneração de protoplastos de Magnaporthe grisea

    OpenAIRE

    Marchi,Carlos Eduardo; Brommonschenkel,Sérgio Hermínio; Queiroz,Marisa Vieira de; Mizubuti,Eduardo Seiti Gomide

    2006-01-01

    Protoplastos são ferramentas biológicas importantes para pesquisas em fungos filamentosos, sendo empregados intensamente em transformação genética. O isolamento de protoplastos de Magnaporthe grisea foi facilitado com Novozym 234, contudo, este complexo enzimático encontra-se indisponível no mercado. Assim, objetivou-se comparar a eficiência de enzimas líticas disponíveis comercialmente na obtenção de protoplastos de M. grisea. Paralelamente, analisaram-se estabilizadores osmóticos, tempos de...

  12. Sequence analysis and expression pattern of MGTA1 gene in rice blast pathogen Magnaporthe grisea

    Institute of Scientific and Technical Information of China (English)

    WANG Jiao-yu; LIU Xiao-hong; LU Jian-ping; LIN Fu-cheng

    2005-01-01

    MGTA1, a putative fungal Zn(Ⅱ)2Cys6 transcriptional activator-encoding gene, was isolated from rice blast pathogen Magnaporthe grisea, which is homologous to CLTA1 from Colletotrichum lindemuthianum with 51% identity at protein level.MGTA1 cassette contains a 2370 bp open reading frame, consisting of 6 exons, coding a 790 amino acid peptide. MGTA1 gene exists as a single copy in genomes of 7 strains of M. grisea, and is expressed in tip hyphae, conidia, and mature appressoria of strain Guy 11.

  13. Sequence analysis and expression pattern of MGTA1 gene in rice blast pathogen Magnaporthe grisea *

    Science.gov (United States)

    Wang, Jiao-yu; Liu, Xiao-hong; Lu, Jian-ping; Lin, Fu-cheng

    2005-01-01

    MGTA1, a putative fungal Zn(II)2Cys6 transcriptional activator-encoding gene, was isolated from rice blast pathogen Magnaporthe grisea, which is homologous to CLTA1 from Colletotrichum lindemuthianum with 51% identity at protein level. MGTA1 cassette contains a 2370 bp open reading frame, consisting of 6 exons, coding a 790 amino acid peptide. MGTA1 gene exists as a single copy in genomes of 7 strains of M. grisea, and is expressed in tip hyphae, conidia, and mature appressoria of strain Guy11. PMID:16052717

  14. Recovery and Biological Properties of Nitrate Non-utilizing Mutants of Rice Blast, Magnaporthe grisea

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chuan-qing; ZHOU Ming-guo

    2004-01-01

    Eleven nitrate non-utilizing (nit) mutants were recovered from six isolates of Magnaporthe grisea cultured on MM media amended with 60 g/L potassium chlorate, with a frequency of 1.42 %. Some biological properties, such as growth rate, growth biomass, cultural characters, conidial production, sexual reproduction ability, and pathogenicity were compared between nit mutants and their parent isolates. Results showed that all the nit mutants were resistant to chlorate. Some important biological properties such as the growth rate on YPSA, conidial production ability on TPSA, pathogenicity, had no significant differences between nit mutants and their parent isolates. Mating type didn't change, but perithecia production ability of fertile isolates changed significantly as compared with that of their parent isolates. Therefore, the nit can be used as a genetic marker to study the genetics such as pathogenicity, fungicide resistance in Magnaporthe grisea.

  15. Structure and Expression of Several Putative Cdc42-Interacting Proteins in Magnaporthe grisea

    Institute of Scientific and Technical Information of China (English)

    ZHENG Wu; CHEN Ji-sheng; ZHENG Shi-qin; LU Guo-dong; WANG Zong-hua

    2006-01-01

    MgCdc42 (Cdc42 in Magnaporthe grisea), with high homology to ScCdc42 (Cdc42 in Saccharomyces cerevisiae), has been demonstrated to involve in the morphogenesis and infection process. To further understand the signaling network,the putative MgCdc42-interacting proteins were analyzed. ScCdc42-interacting protein sequences were first used to BLAST against the M. grisea genome database to retrieve their corresponding analogs. Subsequently, conserved domains of these proteins were compared and expression patterns of their encoding genes in different MgCdc42 mutation states were analyzed by semiquantitative RT-PCR. All retrieved analogs of ScCdc42-interacting proteins from the M.grisea database have conserved domains as those in S. cerevisiae. Expression of their encoding genes increased in MgCdc42CA mutant and decreased in MgCdc42KO mutant. However, MgBem1, Chm1, and MgGic1 in MgCdc42DN mutant had the same expression level as that in the wild type, although MgBem4, MgBoi2, MgCdc24, MgGic2, MgRga1,and Mst20 had decreased expression level, as expected. Overall, it is concluded that there may exist a similar Cdc42 signal pathway in M. grisea as in S. cerevisiae and MgCdc42 plays a key role in the pathway.

  16. Vegetative Compatibility and Asexual Recombination in Magnaporthe grisea from Jiangsu Province, China

    Institute of Scientific and Technical Information of China (English)

    WANG Yan-li; ZHANG Zheng-guang; ZHENG Xiao-bo

    2003-01-01

    Vegetative compatibility among isolates of different races in Magnaporthe grisea collectedfrom Jiangsu Province and asexual recombination among compatible isolates by anastomosis were tested.Twenty isolates involving seven races from diseased rice plants were paired on polished rice rose bengal mediumand incubated at 25℃ in darkness for 18 days. Among 173 pairings tested, solid hyphai fusion lines formed byanastomosis between 124 pairings, indicated that these isolates were vegetative compatible with each other.The result showed that most M. grisea isolates were vegetative compatible. Furthermore, 17 vegetative com-patible pairings between monoconidial isolates with MBCsIPTr marker and isolates with MBCrIPTs markerwere selected to detect the asexual recombination between the compatible isolates of different races. The asexu-al recombinants with MBCrIPTr marker were detected in single hyphal fragment progenies in thirteen of theseventeen pairings. The percentage of recombinants was about 0.6 - 11.3%. Results showed that vegetative com-patibility was prevailing among isolates of M. grisea in Jiangsu Province in vitro. These results also suggested thatasexual recombination may be an important mechanism for M. grisea to maintain genetic diversity in nature.

  17. Detection of Sensitivity and Resistance Variation of Magnaporthe grisea to Kitazin P,Carbendazim and Tricyclazole

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chuan-qing; ZHOU Ming-guo; SHAO Zhen-run; LIANG Gui-mei

    2004-01-01

    One hundred and twenty-nine isolates of Magnaporthe grisea from Guangdong, Guangxi, Anhui and Jiangsu provinces of China were tested for resistance frequency to kitazin P and carbendazim, respectively by the distinctive concentration method.The resistance frequency of the isolates to kitazin P which had not been used in practice for about ten years was as high as 79.1%,and only one carbendazim-resistant isolate was detected in Gaoyao, Guangdong Province (with a frequency of 0.78%). Meanwhile,the minimum inhibition concentration (MIC) of hyphal melanization was adopted to detect the sensitivity of M. grisea to tricyclazole.There existed several different degrees of sensitivity to tricyclazole in the melanin biosynthesis of M. grisea, but no relationship was found between these MIC values completely inhibiting melanization in hyphae and the EC50 values of tricyclazole against rice blast tested in vivo. After the isolates were induced by chemical taming or UV irradiation in laboratory, kitazin P-resistant and carbendazim-resistant mutants were recovered by both the methods, but none of tricyclazole-resistant mutant was obtained.

  18. Sensitivity Detection Technique and Resistance Risk Assessment of Magnaporthe grisea to Tricyclazole

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In vitro detection method for the sensitivity of Magnaporthe grisea to tricyclazole was studied, and the potential resistance risk of blast disease to tricyclazole was assessed. Both EC50 of hyphal melanization (EC50-H) and minimum inhibitive concentration of melanization in appressorial (MIC-A) by inhibitortricyclazole showed positive correlation to the EC50 of tricyclazole against blast disease tested in vivo, with relative co-efficiency (R2) of 0.8995 and 0.8244, respectively. However, stability and reproducibility of EC50-H were better than those of MIC-A, suggesting that it could be used to detect the sensitivity of M. grisea to tricyclazole in vitro. Tricyclazole sensitivity of the progenies derived from single spores of the most sensitive isolate DY2 and the least sensitive isolate GY6 detected in sensitivity monitoring in 2000 was not stable, with mean EC50 values of 4.4968 μg/mL and 5.4010 μg/mL, respectively, indicating that the difference in EC50 between DY2 and GY6 was not caused probably by resistance variation. EC50 of GY6 did not increase significantly when continuously selected for twenty generations under the selection pressure of tricyclazole in vivo. However, the sensitivity of DY2 was decreased by 10-fold after selected for twenty generations.The results suggested that tricyclazole was still low resistance risk for M. grisea in China.

  19. Resistance Evaluation of Some Hybrid Rice, Conventional Early Indica and Late Japonica Rice to Magnaporthe grisea

    Institute of Scientific and Technical Information of China (English)

    SHEN Ying; Adreit Henry; ZHU Xu-dong; Milazzo Joelle; CHEN Hong-qi; Tharreau Didier

    2003-01-01

    Thirty isolates of Magnaporthe grisea collected from 18 provinces/cities representing 21 pathotypes and 9 different lineages were inoculated to rice varieties with known resistance genes and some hybrid rices,conventional early indica and late japonica varieties cultivated recently in China.Virulence spectrum of the 30 isolates was very different,showing that they recognize numerous different resistance genes.Varieties also revealed very different resistance patterns showing that they carry different resistance genes or combinations of resistance genes.On the basis of comparisons with international differential varieties with known resistance genes,resistance genes in certain Chinese varieties could be speculated.The results indicated that some of them were resistant to most of the isolates tested and that they could be of interest as resistance sources for hybrid parents or to be planted in the field directly.

  20. Distribution of Magnaporthe grisea Population and Virulence of Predominant Race in Jiangsu Province,China

    Institute of Scientific and Technical Information of China (English)

    LIU Yong-feng; CHEN Zhi-yi; HU Ming; LI Lian; LIU You-zhou

    2004-01-01

    Three hundred and forty-two mono-conidial isolates were obtained from rice blast specimens collected from five typical areas in Jiangsu Province during 2000-2002. The isolates could be classified into seven groups, thirty races when assessed with seven Chinese differential rice cultivars. The race ZG1 was predominant one of Magnaporthe grisea with a frequency of 65.00% in 2000, 56.90% in 2001 and 60.38% in 2002; the races ZB and ZC groups were also important in Jiangsu Province. By inoculating 130 ZG1 race isolates on thirteen Japanese cultivars with known resistance genes, forty-two pathotypes were found. Among them,30.77% of ZG1 race isolates had virulence to rice cultivars Shin 2(Pita-ks, Pi-eh), K1 (Pi-ta), Pi 4(Pi-ta2, Pi-sh), being the predominant pathotype, indicating the resistances of cultivars Shin 2 (Pita-ks, Pi-sh), K1 (Pi-ta), Pi 4(Pi-ta2, Pi-sh) had lost the resistance in Jiangsu Province. Rice cultivar K3(Pi-kh) was highly resistant to Magnaporthe grisea with 100% resistance frequency, and resistant to the two single isolates, 2003-184(ZC5) and 2003-14-1(ZG1), however, it was infected by a mixture of the two isolates. It was suggested that the change in virulence stemmed from the interaction of different pathotype isolates was one of the reasons that made variety lose its resistance.

  1. Physiological Macro-lesions Enhanced Resistance to Blast (Magnaporthe grisea) in Rice Near-isogenic Lines

    Institute of Scientific and Technical Information of China (English)

    HUANG Shi-wen; LU Ji-ying; LUO Kun; ZHANG Xiu-fu; QIAN Qian

    2005-01-01

    Roll-leaf-1 (rl-1) and spot-leaf-1 (spl-1) were two near-isogenic lines, which were obtained after 3 to 4 backcrosses withearly season indica rice Zhefu 802 as recurrent parent. Henna macro-lesions, referred as physiological or morphological markers,began to appear on leaves at 4.5- to 6.0-leaf stage. The rice seedlings were inoculated at 3.5-, 5.0- and 7.0-leaf stages with highpathogenic races Zhong A1 and Zhong B1 of Magnaporthe grisea, respectively. The resistance of rl-1, spl-1 and Zhefu 802 againstblast was significantly different. The seedlings of Zhefu 802 at 3.5- to 7.0-leaf stage were susceptible to races Zhong A1 and ZhongB1 of M. grisea, whereas those of rl-1 and spl-1 at 3.5-, 5.0- and 7.0-leaf stages were susceptible, moderately resistant andresistant, respectively. These results suggested that the enhanced resistance of ri-1 and spl-1 related to the appearance of theirmorphological marker lesions. The experiment provided a basis for studying lesion mimic and hypersensitive response inassociation with disease resistance.

  2. Population structure and dynamics of Magnaporthe grisea in the Indian Himalayas.

    Science.gov (United States)

    Kumar, J; Nelson, R J; Zeigler, R S

    1999-07-01

    The population genetics of Magnaporthe grisea, the rice blast pathogen, were analyzed in a center of rice diversity (the Uttar Pradesh hills of the Indian Himalayas) using multilocus and single-, or low-copy, DNA markers. Based on DNA fingerprinting with the multilocus probe MGR586 and single-locus probes, 157 haplotypes clustered into 56 lineages (at >/=70% MGR586 band similarity, each with unique single-locus profiles) and high diversity indices were detected among 458 isolates collected from 29 sites during 1992-1995. Most valleys sampled had distinct populations (73% of the lineages were site specific) with some containing one or a few lineages, confirming the importance of clonal propagation, and others were very diverse. Widely distributed lineages suggested that migration occurs across the region and into the Indo-Gangetic plains. Repeated sampling at one site, Matli, (170 isolates, 1992-1995) yielded 19 lineages and diversity significantly greater than that reported from similar samples from Colombia and the Philippines. Analysis of allelic associations using pairwise comparisons and multilocus variance analysis failed to reject the hypothesis of gametic phase equilibrium. The Matli population shifted from highly diverse in 1992 to almost complete dominance by one lineage in 1995. Such population dynamics are consistent with recombination followed by differential survival of clonal descendants of recombinant progeny. At another site, Ranichauri, population (n = 84) composition changed from 2 to 11 lineages over 2 yr and yielded additional evidence for equilibrium. Sexually fertile and hermaphrodite isolates of both mating types were recovered from rice in both Matli and Ranichauri. We demonstrate that Himalayan M. grisea populations are diverse and dynamic and conclude that the structure of some populations may be affected to some extent by sexual recombination.

  3. In silico Analysis of the Potential Infection Mechanisms of Magnaporthe grisea from Horizontal Gene Transfer Hypothesis

    Institute of Scientific and Technical Information of China (English)

    Chunyang Li; Ying Wang; Hao Peng; Hejiao Bian; Mingwei Min; Longfei Chen; Qian Liu; Jinku Bao

    2009-01-01

    Horizontal gene transfer(HGT)has long been considered as a principal force for an organism to gain novel genes in genome evolution. Homology search, phylogenetic analysis and nucleotide composition analysis are three major objective approaches to arguably determine the occurrence and directionality of HGT. Here, 21 genes that possess the potential to horizontal transfer were acquired from the whole genome of Magnaporthe grisea according to annotation, among which three can-didate genes(corresponding protein accession numbers are EAA55123, EAA47200 and EAA52136)were selected for further analysis. According to BLAST homology results, we subsequently conducted phylogenetic analysis of the three candidate HGT genes. Moreover, nucleotide composition analysis was conducted to further validate these HGTs. In addition, the functions of the three candidate genes were searched in COG database. Consequently, we conclude that the gene encoding protein EAA55123 is transferred from Clostridium perfringens. Another HGT event is between EAA52136 and a certain metazoan's corresponding gene, but the direction remains uncertain. Yet, EAA47200 is not a transferred gene.

  4. Pathotype Structure of Magnaporthe grisea in the Fields of Chongyang and Yuan'an in Hubei Province,China

    Institute of Scientific and Technical Information of China (English)

    YANG Xiao-lin; ZHANG Shu; LU Liang; CHANG Xiang-qian; YUAN Bing; YU Da-zhao

    2011-01-01

    [Objective] This study aimed to explore the pathotype structure of Magnaporthe grisea in Chongyang and Yuan'an in Hubei Province,China.[Method] From the rice-growing fields of Chongyang and Yuan'an in Hubei Province where rice blast occurs frequently,60 isolates which were pathotyped against two sets of host differentials:Chinese host differentials and CO39 NILs,were obtained.Then,20 pathotypes with the six indica host differentials(CO39 NILs) were observed,while 13 pathotypes in four race groups were observed out of the same single spore isolates with Chinese host differentials which consists of three indica cultivars and four japonica cultivars.The diversity of the pathotypes of M.grisea populations tested by CO39 NILs was 2.54 and the pathotype 137.1 occurred at predominantly high frequency(21.67%).The diversity of physiological races of M.grisea populations tested by Chinese host differentials was 1.22 and the race group ZA occurred at predominantly high frequency(73.33%).The diversity of physiological races of M.grisea in Chongyang and Yuan'an were also calculated.Overall,the diversity of pathotypes of M.grisea in Yuan'an was higher than that in Chongyang with the two sets of the host differentials.[Conclusion] This study provided current information on the pathotype spectrum of M.grisea populations in the rice fields of Hubei Province to allow the formulation of viable strategies for blast resistance breeding programs in Hubei Province.

  5. A user friendly method to isolate and single spore the fungi Magnaporthe oryzae and Magnaporthe grisea obtained from diseased field samples

    Science.gov (United States)

    The fungus Magnaporthe oryzae is the causal agent for a wide range of plant diseases including diseases of rice, wheat, rye grass, turfgrass and pearl millet. A simple robust procedure for fungal isolation is not publicly available. In the present study, a user friendly method was developed to iso...

  6. Induced Pib Expression and Resistance to Magnaporthe grisea are Compromised by Cytosine Demethylation at Critical Promoter Regions in Rice.

    Science.gov (United States)

    Li, Yuan; Xia, Qiong; Kou, Hongping; Wang, Dan; Lin, Xiuyun; Wu, Ying; Xu, Chunming; Xing, Shaochen; Liu, Bao

    2011-10-01

    Pib is a well-characterized rice blast-resistance gene belonging to the nucleotide binding site (NBS) and leucine-rich repeat (LRR) superfamily. Expression of Pib was low under non-challenged conditions, but strongly induced by the blast-causing fungal pathogen Magnaporthe grisea, thereby conferring resistance to the pathogen. It is generally established that cytosine methylation of the promoter-region often plays a repressive role in modulating expression of the gene in question. We report here that two critical regions of the Pib promoter were heavily CG cytosine-methylated in both cultivars studied. Surprisingly, induced expression of Pib by M. grisea infection did not entail its promoter demethylation, and partial demethylation by 5-azacytidine-treatment actually reduced Pib expression relative to wild-type plants. Accordingly, the blast disease-resistance was compromised in the 5'-azaC-treated plants relative to wild-type. In contrast, the disease susceptibility was not affected by the 5'-azaC treatment in another two rice cultivars that did not contain the Pib gene, ruling out effects of other R genes and non-specific genotoxic effects by the drug-treatment as a cause for the compromised Pib-conditioned blast-resistance. Taken together, our results suggest that promoter DNA methylation plays a novel enhancing role in conditioning high-level of induced expression of the Pib gene in times of M. grisea infection, and its conferred resistance to the pathogen.

  7. Induced Pib Expression and Resistance to Magnaporthe grisea are Compromised by Cytosine Demethylation at Critical Promoter Regions in Rice

    Institute of Scientific and Technical Information of China (English)

    Yuan Li; Qiong Xia; Hongping Kou; Dan Wang; Xiuyun Lin; Ying Wu; Chunming Xu; Shaochen Xing

    2011-01-01

    Pib is a well-characterized rice blast-resistance gene belonging to the nucleotide binding site (NBS) and leucine-rich repeat (LRR) superfamily.Expression of Pib was low under non-challenged conditions,but strongly induced by the blast-causing fungal pathogen Magnaporthe grisea,thereby conferring resistance to the pathogen.It is generally established that cytosine methylation of the promoter-region often plays a repressive role in modulating expression of the gene in question.We report here that two critical regions of the Pib promoter were heavily CG cytosine-methylated in both cultivars studied.Surprisingly,induced expression of Pib by M.grisea infection did not entail its promoter demethylation,and partial demethylation by 5-azacytidine-treatment actually reduced Pib expression relative to wildtype plants.Accordingly,the blast disease-resistance was compromised in the 5’-azaC-treated plants relative to wild-type.In contrast,the disease susceptibility was not affected by the 5’-azaC treatment in another two rice cultivars that did not contain the Pib gene,ruling out effects of other R genes and non-specific genotoxic effects by the drug-treatment as a cause for the compromised Pib-conditioned blast-resistance.Taken together,our results suggest that promoter DNA methylation plays a novel enhancing role in conditioning high-level of induced expression of the Pib gene in times of M.grisea infection,and its conferred resistance to the pathogen.

  8. Construction and Evaluation of a TAC Library of Magnaporthe grisea%稻瘟菌TAC文库的构建与评价

    Institute of Scientific and Technical Information of China (English)

    魏士平; 王扬; 刘耀光; 国立耘; 李家瑞; 彭友良

    2003-01-01

    A TAC library of rice blast fungus, Magnaporthe grisea, was constructed in a vector pYLTAC7. The librarycontains 16 128 individual clones and approximately 74% of the clones harbor foreign DNA inserts with an average size of59 kb. The content of the library corresponds to 18 equivalents of the genome. To confirm the representative of the library,three single-copy DNA markers were used as probes to hybridize with the library clones on the high-density membranes. Six-teen, 17 and 16 positive clones were obtained respectively from the library screening, and the numbers of positive clonesmatching corresponding probes are consistent with the estimated coverage of the library. Further analysis of the restrictionenzyme maps of 8 positive clones screened with a single copy marker, MH18S1, revealed that the contigs covered a 153 kbregion without chimerism or deletion. It is suggested that the TAC library is suitable for genome analysis of M. grisea.%本文构建了一个包含16128个克隆的稻瘟菌基因组的TAC文库,74%的克隆含有外源插入片段,其插入片段大小平均为59kb,该库相当于稻瘟菌基因组的18倍.本文并对文库的代表性进行了评价,采用3个单拷贝的标记作为探针筛库,分别得到16,17和16个阳性克隆,这与估算的该库的覆盖率是一致的;从MH18S1为探针所筛选的阳性克隆中,随机挑取8个并对其限制性酶切图谱进行分析,结果表明:其组成的重叠群跨度为153kb,未发现嵌合和缺失现象.以上结果表明,此TAC文库适合用于稻瘟菌基因组的分析.

  9. Mating Type Alleles,Female Fertility and Genetic Diversity of Magnaporthe grisea Populations Pathogenic to Rice from Some Asian Countries

    Institute of Scientific and Technical Information of China (English)

    SHEN Ying; Joelle Milazzo; YUAN Xiao-ping; Henry Adreit; WANG Yan-li; Jean Loup Notteghem; Didier Tharreau

    2003-01-01

    Five hundred and twenty-two isolates of Magnaporthe grisea isolated from rice in 5 Asian countries were characterized for their mating type by crossing them with 4 hermaphroditic isolates (KA3 and TH2: MAT1.1; Guy11 and TH-16: MAT1.2). Among them, 41% were MAT1.1 and 25% were MAT1.2.The remaining 34% did not produce perithecia with any of the 4 hermaphroditic testers. In Bangladesh, India,Nepal, Vietnam and in most provinces of China, both mating types were present. Only one mating type was found in 3 provinces and 1 city of China. Almost all the isolates had very low fertility, as they were in general female sterile and sometimes also male sterile. Hermaphroditic isolates were recovered from the 5 countries. In these countries, they represented between 13% and 75% of the isolates. In Zhejiang, Guizhou, Guangdong,Hunan, Yunnan and H-ubei provinces of China, hermaphroditic isolates represented between 6% and 67%.The genetic diversity of 143 isolates from these countries and provinces, where hermaphroditic isolates had been collected, was analyzed using SCAR markers. Genetic diversity was high and population structure did not resemble classical clonal structure described in most rice growing regions. The existence of sexual reproduction in the field, localization of a center of diversity in China, and migration between countries were discussed in this paper.

  10. Eukaryotic extracellular catalase–peroxidase from Magnaporthe grisea – Biophysical/chemical characterization of the first representative from a novel phytopathogenic KatG group

    Science.gov (United States)

    Zámocký, Marcel; Droghetti, Enrica; Bellei, Marzia; Gasselhuber, Bernhard; Pabst, Martin; Furtmüller, Paul G.; Battistuzzi, Gianantonio; Smulevich, Giulietta; Obinger, Christian

    2012-01-01

    All phytopathogenic fungi have two catalase–peroxidase paralogues located either intracellularly (KatG1) or extracellularly (KatG2). Here, for the first time a secreted bifunctional, homodimeric catalase–peroxidase (KatG2 from the rice blast fungus Magnaporthe grisea) has been produced heterologously with almost 100% heme occupancy and comprehensively investigated by using a broad set of methods including UV–Vis, ECD and resonance Raman spectroscopy (RR), thin-layer spectroelectrochemistry, mass spectrometry, steady-state & presteady-state spectroscopy. RR spectroscopy reveals that MagKatG2 shows a unique mixed-spin state, non-planar heme b, and a proximal histidine with pronounced imidazolate character. At pH 7.0 and 25 °C, the standard reduction potential E°′ of the Fe(III)/Fe(II) couple for the high-spin native protein was found to fall in the range typical for the KatG family. Binding of cyanide was relatively slow at pH 7.0 and 25 °C and with a Kd value significantly higher than for the intracellular counterpart. Demonstrated by mass spectrometry MagKatG2 has the typical Trp118-Tyr251-Met277 adduct that is essential for its predominantly catalase activity at the unique acidic pH optimum. In addition, MagKatG2 acts as a versatile peroxidase using both one- and two-electron donors. Based on these data, structure–function relationships of extracellular eukaryotic KatGs are discussed with respect to intracellular KatGs and possible role(s) in host–pathogen interaction. PMID:21971530

  11. Eukaryotic extracellular catalase-peroxidase from Magnaporthe grisea - Biophysical/chemical characterization of the first representative from a novel phytopathogenic KatG group.

    Science.gov (United States)

    Zámocký, Marcel; Droghetti, Enrica; Bellei, Marzia; Gasselhuber, Bernhard; Pabst, Martin; Furtmüller, Paul G; Battistuzzi, Gianantonio; Smulevich, Giulietta; Obinger, Christian

    2012-03-01

    All phytopathogenic fungi have two catalase-peroxidase paralogues located either intracellularly (KatG1) or extracellularly (KatG2). Here, for the first time a secreted bifunctional, homodimeric catalase-peroxidase (KatG2 from the rice blast fungus Magnaporthe grisea) has been produced heterologously with almost 100% heme occupancy and comprehensively investigated by using a broad set of methods including UV-Vis, ECD and resonance Raman spectroscopy (RR), thin-layer spectroelectrochemistry, mass spectrometry, steady-state & presteady-state spectroscopy. RR spectroscopy reveals that MagKatG2 shows a unique mixed-spin state, non-planar heme b, and a proximal histidine with pronounced imidazolate character. At pH 7.0 and 25 °C, the standard reduction potential E°' of the Fe(III)/Fe(II) couple for the high-spin native protein was found to fall in the range typical for the KatG family. Binding of cyanide was relatively slow at pH 7.0 and 25 °C and with a K(d) value significantly higher than for the intracellular counterpart. Demonstrated by mass spectrometry MagKatG2 has the typical Trp118-Tyr251-Met277 adduct that is essential for its predominantly catalase activity at the unique acidic pH optimum. In addition, MagKatG2 acts as a versatile peroxidase using both one- and two-electron donors. Based on these data, structure-function relationships of extracellular eukaryotic KatGs are discussed with respect to intracellular KatGs and possible role(s) in host-pathogen interaction.

  12. Novel rice genes involved in compatible and incompatible interaction with Magnaporthe grisea

    Institute of Scientific and Technical Information of China (English)

    DONGHaitao; HEZuhua; DONGJixin; WUYuliang; LIDebao

    1998-01-01

    The rice blast disease has been recognized asthe most devastative disease to rice. Because of the diversity of the fungus races, frequent resistance breakdown has become a barrier totraditional breeding.

  13. Single spore isolation and morphological characterization of local Malaysian isolates of rice blast fungus Magnoporthe grisea

    Science.gov (United States)

    Mishra, Ankitta; Ratnam, Wickneswari; Bhuiyan, Md Atiqur Rahman; Ponaya, Ariane; Jena, Khisord K.

    2015-09-01

    Rice blast is a destructive disease, caused by the fungal pathogen Magnaporthe grisea. It causes considerable damage to rice and leads to crop loss in rice growing regions worldwide. Although fungicides can be used to control rice blast, they generate additional cost in rice production and contamination of environment and food. Therefore, the use of resistant varieties is thought to be one of the most economically and environmentally efficient ways of crop protection from the disease. Six new local Malaysian isolates of M. grisea were isolated using single spore isolation method. Five isolates were from infected leaf samples collected from Kompleks Latihan MADA, Kedah and one was from Kelantan. These isolates were identified using morphological characteristics and microscopic studies and later confirmed by ITSequences. These isolates were induced to sporulate and used for greenhouse screening on two differential rice varieties: Mahsuri (susceptible) and Pongsu Seribu 2 (resistant). Among the 6 isolates, isolate number 3 was found to be the most virulent showing high sporulation while isolate number 4 was very slow growing, and the least virulent.

  14. Expression of a Magnaporthe grisea Elicitor and Its Biological Function in Activating Resistance in Rice

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The expression of a protein elicitor from Magnaporthe griesea and its biological function in activating resistance in rice (Oryza sativa L) were reported. The gene of elicitor was expressed in Escherichia coli cells and produced a His6-fusion protein with 42 kD apparent molecular weight on SDS-PAGE. The purified protein could induce the resistance to blast disease, with the control efficiency of 46.47% and 36.41% at the 14th day and the 21st day after blast inoculation, respectively.After treatment with the expressed protein, the phenylalanine ammonia-lyase (PAL) and peroxidase (POD) activities were promoted in rice plants, meanwhile, the transcription levels of STKM, FAD, PBZ1 and PR1 genes were increased in rice plants. Moreover, after comparing the profile of total rice leaf proteins on two-dimensional eiectrophoresis gel, about 14proteins were found to be increased in expression level after the expressed protein treatment. All the results indicated that the expressed protein could act as an elicitor to trigger the resistance in rice.

  15. Nonhost resistance of barley is successfully manifested against Magnaporthe grisea and a closely related Pennisetum-infecting lineage but is overcome by Magnaporthe oryzae

    NARCIS (Netherlands)

    Zellerhoff, N.; Jarosch, B.; Groenewald, J.Z.; Crous, P.W.; Schaffrath, U.

    2006-01-01

    Magnaporthe oryzae is a major pathogen of rice (Oryza sativa L.) but is also able to infect other grasses, including barley (Hordeum vulgare L.). Here, we report a study using Magnaporthe isolates collected from other host plant species to evaluate their capacity to infect barley. A nonhost type of

  16. Metabolomic analysis reveals a common pattern of metabolic re-programming during invasion of three host plant species by Magnaporthe grisea.

    Science.gov (United States)

    Parker, David; Beckmann, Manfred; Zubair, Hassan; Enot, David P; Caracuel-Rios, Zaira; Overy, David P; Snowdon, Stuart; Talbot, Nicholas J; Draper, John

    2009-09-01

    The mechanisms by which biotrophic and hemi-biotrophic fungal pathogens simultaneously subdue plant defences and sequester host nutrients are poorly understood. Using metabolite fingerprinting, we show that Magnaporthe grisea, the causal agent of rice blast disease, dynamically re-programmes host metabolism during plant colonization. Identical patterns of metabolic change occurred during M. grisea infections in barley, rice and Brachypodium distachyon. Targeted metabolite profiling by GC-MS confirmed the modulation of a conserved set of metabolites. In pre-symptomatic tissues, malate and polyamines accumulated, rather than being utilized to generate defensive reactive oxygen species, and the levels of metabolites associated with amelioration of redox stress in various cellular compartments increased dramatically. The activity of NADP-malic enzyme and generation of reactive oxygen species were localized to pathogen penetration sites, and both appeared to be suppressed in compatible interactions. Early diversion of the shikimate pathway to produce quinate was observed, as well as accumulation of non-polymerized lignin precursors. These data are consistent with modulation of defensive phenylpropanoid metabolism by M. grisea and the inability of susceptible hosts to mount a hypersensitive reaction or produce lignified papillae (both involving reactive oxygen species) to restrict pathogen invasion. Rapid proliferation of M. grisea hyphae in plant tissue after 3 days was associated with accelerated nutrient acquisition and utilization by the pathogen. Conversion of photoassimilate into mannitol and glycerol for carbon sequestration and osmolyte production appear to drive hyphal growth. Taken together, our results suggest that fungal pathogens deploy a common metabolic re-programming strategy in diverse host species to suppress plant defence and colonize plant tissue.

  17. Morphological and molecular characterization of Magnaporthe oryzae (fungus) from infected rice leaf samples

    Science.gov (United States)

    Muni, Nurulhidayah Mat; Nadarajah, Kalaivani

    2014-09-01

    Magnaporthe oryzae is a plant-pathogenic fungus that causes a serious disease affecting rice called rice blast. Outbreaks of rice blast have been a threat to the global production of rice. This fungal disease is estimated to cause production losses of US55 million each year in South and Southeast Asia. It has been used as a primary model for elucidating various aspects of the host-pathogen interaction with its host. We have isolated five isolates of Magnaporthe oryzae from diseased leaf samples obtained from the field at Kompleks Latihan MADA, Kedah, Malaysia. We have identified the isolates using morphological and microscopic studies on the fungal spores and the lesions on the diseased leaves. Amplification of the internal transcribed spacer (ITS) was carried out with universal primers ITS1 and ITS4. The sequence of each isolates showed at least 99% nucleotide identity with the corresponding sequence in GenBank for Magnaporthe oryzae.

  18. Investigating the biology of plant infection by the rice blast fungus Magnaporthe oryzae.

    Science.gov (United States)

    Martin-Urdiroz, Magdalena; Oses-Ruiz, Miriam; Ryder, Lauren S; Talbot, Nicholas J

    2016-05-01

    The rice blast fungus, Magnaporthe oryzae, is responsible for the most serious disease of rice and is a continuing threat to ensuring global food security. The fungus has also, however, emerged as a model experimental organism for understanding plant infection processes by pathogenic fungi. This is largely due to its amenability to both classical and molecular genetics, coupled with the efforts of a very large international research community. This review, which is based on a plenary presentation at the 28th Fungal Genetics Conference in Asilomar, California in March 2015, describes recent progress in understanding how M. oryzae uses specialised cell called appressoria to bring about plant infection and the underlying biology of this developmental process. We also review how the fungus is then able to proliferate within rice tissue, deploying effector proteins to facilitate its spread by suppressing plant immunity and promoting growth and development of the fungus.

  19. Caracterização da virulência de Magnaporthe grisea em cultivares diferenciadoras japonesas e linhas quase-isogênicas das cultivares IAC-25 e de CO-39 de arroz Characterization of virulence of Magnaporthe grisea on Japanese differentials, near-isogenic lines of IAC-25 and CO-39 of rice

    Directory of Open Access Journals (Sweden)

    Gisele Barata da Silva

    2007-12-01

    Full Text Available Foi estudada a virulência de 681 isolados de Magnaporthe grisea provenientes de oito lavouras de arroz de terras altas, quatro da cv. BRS Bonança e quatro da cv. Primavera, localizadas em cinco municípios no Estado de Goiás. Foram avaliados 321 isolados de M. grisea de folha e de panícula obtidos da cv. BRS Bonança e 360 da cv. Primavera. Para diferenciar a virulência dos isolados foram utilizados nove cultivares diferenciadoras japonesas, seis linhagens quase-isogências (NIL's da cv. IAC-25, cinco linhagens quase-isogênicas da cv. CO-39, e as cultivares Primavera, BRS Bonança, IAC-25 e CO-39. Os isolados de M. grisea provenientes da cv. BRS Bonança foram mais virulentos nas NIL's de IAC-25 do que isolados da cv. Primavera. A maioria das subpopulações de M. grisea provenientes de folhas e panícula, de ambas as cultivares, foram avirulentos à linhagem quase-isogênica CNA-8212. A virulência, em baixa freqüência, foi observada nos isolados de M. grisea provenientes de BRS Bonança aos genes Pi-z t (Toride-1 e de Primavera aos genes Pi-z (Fukunishiki. Uma baixa freqüência de isolados virulentos foram virulentos nas NIL's C101 LAC (Pi-1 e C101 A 51(Pi-2. Considerando as reações compatíveis e incompatíveis das NIL's de IAC-25 à população de M. grisea de BRS Bonança, o dendrograma mostrou um grupo (90% de similaridade, diferindo do parental recorrente. Por outro lado, a população de 'Primavera', com exceção da CNA-8199, formou um grupo (93% de similaridade, incluindo o parental recorrente. Os genes de resistência Pi-z e Pi-z t das cultivares Fukunishiki e Toride-1, respectivamente, os genes Pi-1 e Pi-2 das NIL's de CO-39 e os genes desconhecidos das NIL's IAC-25, que apresentaram maior espectro de resistência às populações estudadas podem ser utilizados no programa de melhoramento, para desenvolvimento de linhas isogênicas de BRS Bonança e Primavera.The virulence of the population of Magnaporthe grisea collected

  20. Padrão de integração de pAN7-1 em mutantes de Magnaporthe grisea com patogenicidade alterada em arroz pAN7-1 integration pattern in mutants of Magnaporthe grisea impaired in pathogenicity to rice

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Marchi

    2010-03-01

    Full Text Available Ensaios foram conduzidos para verificar a presença, o número de cópias e de sítios de integração de pAN7-1 no genoma de mutantes de M. grisea I-22 com patogenicidade alterada em arroz. Foram analisados T41, T93, T251 (gerados por mutagênese REMI e T108 (oriundo de mutagênese convencional, os quais exibiram diferentes fenótipos mutantes. O DNA total desses mutantes foi submetido à reação em cadeia de polimerase (PCR e às análises de hibridização com o vetor (Southern blot. A presença de pAN7-1 no genoma de todos os mutantes foi confirmada por PCR. Segundo as análises de Southern blot, T41 exibiu duas integrações do vetor, ambas na forma de cópia única. No genoma de T93 também foram detectados dois sítios de inserção de pAN7-1, um dos quais envolvendo múltiplas cópias do vetor. Os resultados indicaram a presença de apenas uma cópia do vetor em um único sítio nos genomas de T108 e T251. O padrão de integração em T251 foi o único a sugerir a ocorrência de evento REMI. As diferenças quanto ao tamanho dos fragmentos com homologia a pAN7-1 refletiram a possível aleatoriedade dos eventos de integração no genoma de M. grisea. Os resultados evidenciaram o potencial de REMI para a mutagênese insercional de M. grisea, quando conduzida com pAN7-1 e HindIIIExperiments were conducted to investigate the presence, number of copies and integration site of pAN7-1 in the genome of mutants of Magnaporthe grisea impaired in pathogenicity to rice. The mutants T41, T93, T251 (obtained by REMI and T108 (obtained by conventional mutagenesis exhibiting different alterations in pathogenicity were analyzed. Polymerase chain reaction (PCR and Southern blot analyses were conducted with total DNA of mutants. The presence of pAN7-1 in genome of mutants was confirmed by PCR. Based in Southern blot analyses, two single-copy integration of vector were detected in T41. Two insertion sites of pAN7-1 were detected in the genome of T93

  1. Potential distribution of Magnaporthe grisea in China and the world,predicted by MaxEnt%基于MaxEnt的麦瘟病在全球及中国的潜在分布区预测

    Institute of Scientific and Technical Information of China (English)

    曹学仁; 陈林; 周益林; 段霞瑜

    2011-01-01

    [目的]麦瘟病是小麦上的一种新病害,明确该病害在全球及我国的潜在分布区域,对于有效控制此病害在全球的扩展蔓延具有重要的意义.[方法]利用MaxEnt生态位模型预测麦瘟病在全球及我国的潜在分布.[结果]南美中东部、非洲东南部和中西部、南亚东南部和东南亚以及澳大利亚东部沿海地区是该病害在全球的主要适生区;而该病害在我国的适生区仅包括云南、广东和海南等省的少数地区.[结论]该病害在我国的适生区较小,但随着全球气候变化,该病原菌的潜在分布范围可能将进一步扩大.%[Objective]Wheat blast is a new wheat disease caused by Magnaporthe grisea, and now it has become one of the major diseases of wheat in South America.It is urgent to determine the potential geographical distribution of M.grisea in China and the world.[Method]The potential distribution regions of M.grisea in the world and China were predicted by using MaxEnt model.[Result]Mid-east of South America, Southeast and Midwest of Africa, southeast of South Asia, Southeast Asia and east coast of Australia are the main suitable areas for M.grisea in the world.The suitable areas for M.grisea cover only some areas in Yunnan, Guangdong and Hainan in China.[Conclusion]The predicted results showed that the suitable areas for M.grisea in China are relatively small.Climate change may make the potential distribution regions of M.grisea larger.

  2. Anacardic acid induces apoptosis-like cell death in the rice blast fungus Magnaporthe oryzae.

    Science.gov (United States)

    Muzaffar, Suhail; Bose, Chinchu; Banerji, Ashok; Nair, Bipin G; Chattoo, Bharat B

    2016-01-01

    Anacardic acid (6-pentadecylsalicylic acid), extracted from cashew nut shell liquid, is a natural phenolic lipid well known for its strong antibacterial, antioxidant, and anticancer activities. Its effect has been well studied in bacterial and mammalian systems but remains largely unexplored in fungi. The present study identifies antifungal, cytotoxic, and antioxidant activities of anacardic acid in the rice blast fungus Magnaporthe oryzae. It was found that anacardic acid causes inhibition of conidial germination and mycelial growth in this ascomycetous fungus. Phosphatidylserine externalization, chromatin condensation, DNA degradation, and loss of mitochondrial membrane potential suggest that growth inhibition of fungus is mainly caused by apoptosis-like cell death. Broad-spectrum caspase inhibitor Z-VAD-FMK treatment indicated that anacardic acid induces caspase-independent apoptosis in M. oryzae. Expression of a predicted ortholog of apoptosis-inducing factor (AIF) was upregulated during the process of apoptosis, suggesting the possibility of mitochondria dependent apoptosis via activation of apoptosis-inducing factor. Anacardic acid treatment leads to decrease in reactive oxygen species rather than increase in reactive oxygen species (ROS) accumulation normally observed during apoptosis, confirming the antioxidant properties of anacardic acid as suggested by earlier reports. Our study also shows that anacardic acid renders the fungus highly sensitive to DNA damaging agents like ethyl methanesulfonate (EMS). Treatment of rice leaves with anacardic acid prevents M. oryzae from infecting the plant without affecting the leaf, suggesting that anacardic acid can be an effective antifungal agent.

  3. Genome analysis of rice-blast fungus Magnaporthe oryzae field isolates from southern India

    Directory of Open Access Journals (Sweden)

    Malali Gowda

    2015-09-01

    Full Text Available The Indian subcontinent is the center of origin and diversity for rice (Oryza sativa L.. The O. sativa ssp. indica is a major food crop grown in India, which occupies the first and second position in area and production, respectively. Blast disease caused by Magnaporthe oryzae is a major constraint to rice production. Here, we report the analysis of genome architecture and sequence variation of two field isolates, B157 and MG01, of the blast fungus from southern India. The 40 Mb genome of B157 and 43 Mb genome of MG01 contained 11,344 and 11,733 predicted genes, respectively. Genomic comparisons unveiled a large set of SNPs and several isolate specific genes in the Indian blast isolates. Avr genes were analyzed in several sequenced Magnaporthe strains; this analysis revealed the presence of Avr-Pizt and Avr-Ace1 genes in all the sequenced isolates. Availability of whole genomes of field isolates from India will contribute to global efforts to understand genetic diversity of M. oryzae population and to track the emergence of virulent pathotypes.

  4. ANTIFUNGAL ACTIVITY OF CHITOSAN AND ONE OF ITS HYDROLYSATES ON Pyricularia grisea, Sacc. FUNGUS

    OpenAIRE

    2003-01-01

    La quitosana y sus derivados reducen marcadamente el crecimiento micelial de algunos hongos con un mayor efecto inhibitorio a elevadas concentraciones. El efecto fungistático y fungicida in vitro de la quitosana y el hidrolizado de quitosana fue investigado sobre el hongo Pyricularia grisea. El experimento se realizó en el laboratorio de Microbiología del Departamento de Fisiología y Bioquímica Vegetal del Instituto Nacional de Ciencias Agrícolas (INCA). Se encontró que ambos principios activ...

  5. The Potential of Streptomyces as Biocontrol Agents against the Rice Blast Fungus, Magnaporthe oryzae (Pyricularia oryzae)

    Science.gov (United States)

    Law, Jodi Woan-Fei; Ser, Hooi-Leng; Khan, Tahir M.; Chuah, Lay-Hong; Pusparajah, Priyia; Chan, Kok-Gan; Goh, Bey-Hing; Lee, Learn-Han

    2017-01-01

    Rice is a staple food source for more than three billion people worldwide. However, rice is vulnerable to diseases, the most destructive among them being rice blast, which is caused by the fungus Magnaporthe oryzae (anamorph Pyricularia oryzae). This fungus attacks rice plants at all stages of development, causing annual losses of approximately 10–30% in various rice producing regions. Synthetic fungicides are often able to effectively control plant diseases, but some fungicides result in serious environmental and health problems. Therefore, there is growing interest in discovering and developing new, improved fungicides based on natural products as well as introducing alternative measures such as biocontrol agents to manage plant diseases. Streptomyces bacteria appear to be promising biocontrol agents against a wide range of phytopathogenic fungi, which is not surprising given their ability to produce various bioactive compounds. This review provides insight into the biocontrol potential of Streptomyces against the rice blast fungus, M. oryzae. The ability of various Streptomyces spp. to act as biocontrol agents of rice blast disease has been studied by researchers under both laboratory and greenhouse/growth chamber conditions. Laboratory studies have shown that Streptomyces exhibit inhibitory activity against M. oryzae. In greenhouse studies, infected rice seedlings treated with Streptomyces resulted in up to 88.3% disease reduction of rice blast. Studies clearly show that Streptomyces spp. have the potential to be used as highly effective biocontrol agents against rice blast disease; however, the efficacy of any biocontrol agent may be affected by several factors including environmental conditions and methods of application. In order to fully exploit their potential, further studies on the isolation, formulation and application methods of Streptomyces along with field experiments are required to establish them as effective biocontrol agents. PMID:28144236

  6. The Potential of Streptomyces as Biocontrol Agents against the Rice Blast Fungus, Magnaporthe oryzae (Pyricularia oryzae).

    Science.gov (United States)

    Law, Jodi Woan-Fei; Ser, Hooi-Leng; Khan, Tahir M; Chuah, Lay-Hong; Pusparajah, Priyia; Chan, Kok-Gan; Goh, Bey-Hing; Lee, Learn-Han

    2017-01-01

    Rice is a staple food source for more than three billion people worldwide. However, rice is vulnerable to diseases, the most destructive among them being rice blast, which is caused by the fungus Magnaporthe oryzae (anamorph Pyricularia oryzae). This fungus attacks rice plants at all stages of development, causing annual losses of approximately 10-30% in various rice producing regions. Synthetic fungicides are often able to effectively control plant diseases, but some fungicides result in serious environmental and health problems. Therefore, there is growing interest in discovering and developing new, improved fungicides based on natural products as well as introducing alternative measures such as biocontrol agents to manage plant diseases. Streptomyces bacteria appear to be promising biocontrol agents against a wide range of phytopathogenic fungi, which is not surprising given their ability to produce various bioactive compounds. This review provides insight into the biocontrol potential of Streptomyces against the rice blast fungus, M. oryzae. The ability of various Streptomyces spp. to act as biocontrol agents of rice blast disease has been studied by researchers under both laboratory and greenhouse/growth chamber conditions. Laboratory studies have shown that Streptomyces exhibit inhibitory activity against M. oryzae. In greenhouse studies, infected rice seedlings treated with Streptomyces resulted in up to 88.3% disease reduction of rice blast. Studies clearly show that Streptomyces spp. have the potential to be used as highly effective biocontrol agents against rice blast disease; however, the efficacy of any biocontrol agent may be affected by several factors including environmental conditions and methods of application. In order to fully exploit their potential, further studies on the isolation, formulation and application methods of Streptomyces along with field experiments are required to establish them as effective biocontrol agents.

  7. Crucial roles of abscisic acid biogenesis in virulence of rice blast fungus Magnaporthe oryzae

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    Carla eSpence

    2015-12-01

    Full Text Available Rice suffers dramatic yield losses due to blast pathogen Magnaporthe oryzae. Pseudomonas chlororaphis EA105, a bacterium that was isolated from the rice rhizosphere, inhibits M. oryzae. It was shown previously that pre-treatment of rice with EA105 reduced the size of blast lesions through JA- and ETH-mediated ISR. ABA acts antagonistically towards SA, JA, and ETH signaling, to impede plant defense responses. EA105 may be reducing the virulence of M. oryzae by preventing the pathogen from up-regulating the key ABA biosynthetic gene NCED3 in rice roots, as well as a β-glucosidase likely involved in activating conjugated inactive forms of ABA. However, changes in total ABA concentrations were not apparent, provoking the question of whether ABA concentration is an indicator of ABA signaling and response. In the rice-M. oryzae interaction, ABA plays a dual role in disease severity by increasing plant susceptibility and accelerating pathogenesis in the fungus itself. ABA is biosynthesized by M. oryzae. Further, exogenous ABA increased spore germination and appressoria formation, distinct from other plant growth regulators. EA105, which inhibits appressoria formation, counteracted the virulence-promoting effects of ABA on M. oryzae. The role of endogenous fungal ABA in blast disease was confirmed through the inability of a knockout mutant impaired in ABA biosynthesis to form lesions on rice. Therefore, it appears that EA105 is invoking multiple strategies in its protection of rice from blast including direct mechanisms as well as those mediated through plant signaling. ABA is a molecule that is likely implicated in both tactics.

  8. Comparative analysis of the genomes of two field isolates of the rice blast fungus Magnaporthe oryzae.

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    Minfeng Xue

    Full Text Available Rice blast caused by Magnaporthe oryzae is one of the most destructive diseases of rice worldwide. The fungal pathogen is notorious for its ability to overcome host resistance. To better understand its genetic variation in nature, we sequenced the genomes of two field isolates, Y34 and P131. In comparison with the previously sequenced laboratory strain 70-15, both field isolates had a similar genome size but slightly more genes. Sequences from the field isolates were used to improve genome assembly and gene prediction of 70-15. Although the overall genome structure is similar, a number of gene families that are likely involved in plant-fungal interactions are expanded in the field isolates. Genome-wide analysis on asynonymous to synonymous nucleotide substitution rates revealed that many infection-related genes underwent diversifying selection. The field isolates also have hundreds of isolate-specific genes and a number of isolate-specific gene duplication events. Functional characterization of randomly selected isolate-specific genes revealed that they play diverse roles, some of which affect virulence. Furthermore, each genome contains thousands of loci of transposon-like elements, but less than 30% of them are conserved among different isolates, suggesting active transposition events in M. oryzae. A total of approximately 200 genes were disrupted in these three strains by transposable elements. Interestingly, transposon-like elements tend to be associated with isolate-specific or duplicated sequences. Overall, our results indicate that gain or loss of unique genes, DNA duplication, gene family expansion, and frequent translocation of transposon-like elements are important factors in genome variation of the rice blast fungus.

  9. Osa-miR169 Negatively Regulates Rice Immunity against the Blast Fungus Magnaporthe oryzae

    Science.gov (United States)

    Li, Yan; Zhao, Sheng-Li; Li, Jin-Lu; Hu, Xiao-Hong; Wang, He; Cao, Xiao-Long; Xu, Yong-Ju; Zhao, Zhi-Xue; Xiao, Zhi-Yuan; Yang, Nan; Fan, Jing; Huang, Fu; Wang, Wen-Ming

    2017-01-01

    miR169 is a conserved microRNA (miRNA) family involved in plant development and stress-induced responses. However, how miR169 functions in rice immunity remains unclear. Here, we show that miR169 acts as a negative regulator in rice immunity against the blast fungus Magnaporthe oryzae by repressing the expression of nuclear factor Y-A (NF-YA) genes. The accumulation of miR169 was significantly increased in a susceptible accession but slightly fluctuated in a resistant accession upon M. oryzae infection. Consistently, the transgenic lines overexpressing miR169a became hyper-susceptible to different M. oryzae strains associated with reduced expression of defense-related genes and lack of hydrogen peroxide accumulation at the infection site. Consequently, the expression of its target genes, the NF-YA family members, was down-regulated by the overexpression of miR169a at either transcriptional or translational level. On the contrary, overexpression of a target mimicry that acts as a sponge to trap miR169a led to enhanced resistance to M. oryzae. In addition, three of miR169’s target genes were also differentially up-regulated in the resistant accession upon M. oryzae infection. Taken together, our data indicate that miR169 negatively regulates rice immunity against M. oryzae by differentially repressing its target genes and provide the potential to engineer rice blast resistance via a miRNA. PMID:28144248

  10. Mutation for Pathogenicity of Magnaporthe grisea by Restriction Enzyme Mediated Integration(REMI)%稻瘟病菌限制酶介导整合(REMI)转化的致病性诱变

    Institute of Scientific and Technical Information of China (English)

    张文荟; 周益军; 范永坚; 程兆榜; 吴淑华

    2002-01-01

    应用提高真菌转化率的技术——限制酶介导整合(restriction enzyme mediated integration,REMI)技术转化稻瘟病菌株Magnaporthe grisea131原生质体,在限制酶HindIII, KpnI或SacI介导下转化效率分别提高6.5、10、3.7倍.通过300μg/mL潮霉素筛选获得1000个以上转化子.用突变体接种水稻鉴别品种,发现其中M25和M36与M131比较其致病性发生了改变.另外还发现产孢缺陷型突变体和培养性状发生改变的突变菌株.rep-PCR试验表明REMI突变菌株由于质粒插入而与M131指纹有差异.

  11. Inhibitory activity of antibiotic substances extraction induced by salicylic acid in rice leaves against Magnaporthe grisea%水杨酸诱导水稻抗菌物质对稻瘟病菌的抑制作用

    Institute of Scientific and Technical Information of China (English)

    王瑞霞; 王振中; 纪春艳; 李云锋; 董章勇

    2011-01-01

    采用平板法和气相色谱-质谱联用(GC-MS)方法,研究水杨酸(salicylic acod,SA)诱导处理水稻后产生的小分子的抗菌物质对稻瘟病菌(Magnaporthe grisea)孢子萌发的影响以及含量的变化.结果表明:水杨酸诱导处理后的水稻叶片提取物质对稻瘟病菌孢子萌发具有抑制作用;水杨酸诱导处理后,水稻的2个品系CO39和CIA101A51产生了分支酸、丁子香酚、稻壳酮A(Momilactone A,MA)、稻壳酮B(Momilactone B,MB)4种化合物,且水杨酸甲酯、苯酚、豆甾醇和β-谷甾醇、2种酯类物质、十一碳烷等化合物含量均发生变化.水杨酸诱导处理可以调动抗病相关的次生代谢过程,合成植保素及其他抗菌物质,从而提高植物的抗病性.%The low-molecular-weight antibiotic substances of low molecular weight induced in rice leaves by salicylic acid(SA) treatment were studied. Plate method was used to detect the effect of the extract on spore germination and Gas chromatography-mass spectrometry(GC-MS) was used to analyse these low-molecular-weight antibiotic substances. The results showed that the induced substances can effectively inhibit spore germination in Ma gna porthe grisea. GC-MS analysis also revealed that SA could significantly induce many kinds of low-molecular-weight compounds in rice leaves and that their content was increased as compared to the control group. SA could cause the production of momilactone A, mo milactone B, eugenol, and chorismic acid evidently, SA could alter the levels of phenol, methyl salicy late, stigmasterol, β-sitosterol, undecane and methyl ester. These results provided direct evidence that the rice plant produces phytoalexins in response to SA treatment.

  12. Rice blast fungus (Magnaporthe oryzae) infects Arabidopsis via a mechanism distinct from that required for the infection of rice.

    Science.gov (United States)

    Park, Ju-Young; Jin, Jianming; Lee, Yin-Won; Kang, Seogchan; Lee, Yong-Hwan

    2009-01-01

    Magnaporthe oryzae is a hemibiotrophic fungal pathogen that causes rice (Oryza sativa) blast. Although M. oryzae as a whole infects a wide variety of monocotyledonous hosts, no dicotyledonous plant has been reported as a host. We found that two rice pathogenic strains of M. oryzae, KJ201 and 70-15, interacted differentially with 16 ecotypes of Arabidopsis (Arabidopsis thaliana). Strain KJ201 infected all ecotypes with varying degrees of virulence, whereas strain 70-15 caused no symptoms in certain ecotypes. In highly susceptible ecotypes, small chlorotic lesions appeared on infected leaves within 3 d after inoculation and subsequently expanded across the affected leaves. The fungus produced spores in susceptible ecotypes but not in resistant ecotypes. Fungal cultures recovered from necrotic lesions caused the same symptoms in healthy plants, satisfying Koch's postulates. Histochemical analyses showed that infection by the fungus caused an accumulation of reactive oxygen species and eventual cell death. Similar to the infection process in rice, the fungus differentiated to form appressorium and directly penetrated the leaf surface in Arabidopsis. However, the pathogenic mechanism in Arabidopsis appears distinct from that in rice; three fungal genes essential for pathogenicity in rice played only limited roles in causing disease symptoms in Arabidopsis, and the fungus seems to colonize Arabidopsis as a necrotroph through the secretion of phytotoxic compounds, including 9,12-octadecadienoic acid. Expression of PR-1 and PDF1.2 was induced in response to infection by the fungus, suggesting the activation of salicylic acid- and jasmonic acid/ethylene-dependent signaling pathways. However, the roles of these signaling pathways in defense against M. oryzae remain unclear. In combination with the wealth of genetic and genomic resources available for M. oryzae, this newly established pathosystem allows comparison of the molecular and cellular mechanisms underlying

  13. Adaptation to pH and role of PacC in the rice blast fungus Magnaporthe oryzae.

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    Patricia Landraud

    Full Text Available Fungi are known to adapt to pH partly via specific activation of the Pal signaling pathway and subsequent gene regulation through the transcription factor PacC. The role of PacC in pathogenic fungi has been explored in few species, and each time its partaking in virulence has been found. We studied the impact of pH and the role of PacC in the biology of the rice pathogen Magnaporthe oryzae. Conidia formation and germination were affected by pH whereas fungal growth and appressorium formation were not. Growth in vitro and in planta was characterized by alkalinization and ammonia accumulation in the surrounding medium. Expression of the MoPACC gene increased when the fungus was placed under alkaline conditions. Except for MoPALF, expression of the MoPAL genes encoding the pH-signaling components was not influenced by pH. Deletion of PACC caused a progressive loss in growth rate from pH 5 to pH 8, a loss in conidia production at pH 8 in vitro, a loss in regulation of the MoPALF gene, a decreased production of secreted lytic enzymes and a partial loss in virulence towards barley and rice. PacC therefore plays a significant role in M. oryzae's biology, and pH is revealed as one component at work during interaction between the fungus and its host plants.

  14. Two Rab5 Homologs Are Essential for the Development and Pathogenicity of the Rice Blast Fungus Magnaporthe oryzae

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    Cheng D. Yang

    2017-05-01

    Full Text Available The rice blast fungus, Magnaporthe oryzae, infects many economically important cereal crops, particularly rice. It has emerged as an important model organism for studying the growth, development, and pathogenesis of filamentous fungi. RabGTPases are important molecular switches in regulation of intracellular membrane trafficking in all eukaryotes. MoRab5A and MoRab5B are Rab5 homologs in M. oryzae, but their functions in the fungal development and pathogenicity are unknown. In this study, we have employed a genetic approach and demonstrated that both MoRab5A and MoRab5B are crucial for vegetative growth and development, conidiogenesis, melanin synthesis, vacuole fusion, endocytosis, sexual reproduction, and plant pathogenesis in M. oryzae. Moreover, both MoRab5A and MoRab5B show similar localization in hyphae and conidia. To further investigate possible functional redundancy between MoRab5A and MoRab5B, we overexpressed MoRAB5A and MoRAB5B, respectively, in MoRab5B:RNAi and MoRab5A:RNAi strains, but neither could rescue each other’s defects caused by the RNAi. Taken together, we conclude that both MoRab5A and MoRab5B are necessary for the development and pathogenesis of the rice blast fungus, while they may function independently.

  15. Two independent S-phase checkpoints regulate appressorium-mediated plant infection by the rice blast fungus Magnaporthe oryzae

    Science.gov (United States)

    Osés-Ruiz, Míriam; Sakulkoo, Wasin; Littlejohn, George R.; Martin-Urdiroz, Magdalena

    2017-01-01

    To cause rice blast disease, the fungal pathogen Magnaporthe oryzae develops a specialized infection structure called an appressorium. This dome-shaped, melanin-pigmented cell generates enormous turgor and applies physical force to rupture the rice leaf cuticle using a rigid penetration peg. Appressorium-mediated infection requires septin-dependent reorientation of the F-actin cytoskeleton at the base of the infection cell, which organizes polarity determinants necessary for plant cell invasion. Here, we show that plant infection by M. oryzae requires two independent S-phase cell-cycle checkpoints. Initial formation of appressoria on the rice leaf surface requires an S-phase checkpoint that acts through the DNA damage response (DDR) pathway, involving the Cds1 kinase. By contrast, appressorium repolarization involves a novel, DDR-independent S-phase checkpoint, triggered by appressorium turgor generation and melanization. This second checkpoint specifically regulates septin-dependent, NADPH oxidase-regulated F-actin dynamics to organize the appressorium pore and facilitate entry of the fungus into host tissue. PMID:28028232

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

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    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

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

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    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.

  18. Extreme Thermophilic Polypeptide (ETPMG) Exhibited Strong Antagonism to Magnaporthe grisea and its N-terminal Amino Acid Residues Sequencing%ETPMG极端嗜热多肽N-末端氨基酸测序及其对苗瘟的防效

    Institute of Scientific and Technical Information of China (English)

    周华强; 谭芙蓉; 周颖; 郑爱萍; 李平

    2007-01-01

    Two extreme thermophilic polypeptides were isolated from fermentation liquor of LM-3 bacterium of Paenibacillus polymyxa.The inhibition capacity of 5μL purified polypeptides against Magnaporthe grisea reached to 89.6%.These two polypeptides had a molecular weight of 6 000~7 000 D by SDS-PAGE assay and were recovered from electro-lanes for detection of inhibition activity to M.grisea respectively.One polypeptide with strong inhibition activity was named ETPMG(extreme Thermophilic Polypeptide against M. grisea).and the other without such activity was named ETPL3(extreme Thermophilic Polypeptide from LM-3).N-terminal amino acid residues of ETPMG were then sequenced and the determined sequence was H2N-ANDPR.To evaluate its performance against M. grisea in paddy field at seedling stage,5 oil-in-water(O/W) microbial emulsions were confected.ETPMG was used as the active agent of the five emulsions.According to field evaluation,AB4 performed well with a control effect of 80.73% and the weight fraction of its components was 50∶6.5∶1.75∶41.75(ETPMG∶tween80∶emulsifier OP∶methanol).ETPMG was the first reported polypeptide which combined the extreme thermophilic characteristic and strong antagonistic activity against M.grisea.%本试验用加热法从多粘类芽孢杆菌(Paenibacillus polymyxa)LM-3菌株的发酵液中纯化得到2个极端嗜热多肽.平板拮抗实验表明,5μL纯化多肽对稻瘟病菌(Magnaporthe grisea)抑菌率达89.6%.SDS-PAGE电泳显示纯化多肽分子量介于6 000~7 000 D之间.多肽复性后,其中之一对稻瘟病菌表现出强的拮抗活性,命名为ETPMG(extreme thermophilic polypeptide against M. grisea);另一个则无此活性,命名为ETPL3(extreme thermophilic polypeptide from LM-3).ETPMG经氨基酸测序,获得了其N-末端5个氨基酸序列(H2N-ANDPR).以ETPMG为主效成分配得5种微生物源生防乳剂,对水稻苗瘟进行了田间防效试验.试验结果表明,这5种乳剂的防效都优于LM-3

  19. Identification and Evaluation of Resistance of Rice to Magnaporthe grisea in Jiansanjiang Branch of Heilongjiang Land Reclamation General Bureau%建三江管理局水稻品种对稻瘟病的抗性分析

    Institute of Scientific and Technical Information of China (English)

    刘成; 张金成

    2012-01-01

    为筛选出适宜在建三江地区种植的抗稻瘟病水稻品种(系),2011年对建三江地区栽培的31个品种(系)进行叶瘟、穗颈瘟抗性监测并作出鉴定分析。稻瘟病抗病(R)品种(系)有:龙粳28、龙粳29、龙粳30、绥粳10号、龙生01—107、龙生01-028—2共6个品种(系),占总鉴定品种数量的19.35%;中抗病(MR)品种(系)有:垦稻12、垦鉴稻5号、龙盾107、龙粳27、龙育03-1789、龙交04—908共6个品种,占总鉴定品种数量的19.350.4;中感(MS)品种有:垦稻19、垦稻20、垦稻21、垦稻22、垦鉴稻6号、莲稻1号、龙交06-192、龙交06—2110、龙粳20、龙粳21、龙粳25、龙粳26、三江1号、绥粳8号共14个品种,占总鉴定品种数量的45.16%;感病(S)品种有:垦稻17、龙粳31、龙粳32、绥粳3号共4个品种,占总鉴定品种数量的12.90%;高感病(HS)品种有空育131,占总鉴定品种数量的3.23%。并就如何改进稻瘟病抗性鉴定技术提出了见解,讨论了稻瘟病抗性评价在水稻安全生产上的意义。%The resistance of 31 rice varieties to Magnaporthe grisea was analyzed in 2011 to select suitable blast resistance varieties in Jiansanjiang area. The results showed that:high resistance( HR )varieties(strains )were Longjiang 28, Longjiang 29, Longjiang 30, Suijing No. 10, Longsheng 01-107, Longsheng 01-028-2, accounting for 19. 35 % ; Medium resistance (MR) varieties (strains) were Kendao 12, Kenjiandao No. 5, Longdun 107, Longjiang 27, Longyu 03-11789 and Longjiao 04-908, accounting for 19.35 % ; Medium susceptible(MS) varieties(strains)were Kendao 19, Kendao 20, Kendao 21, Kendao 22, Kenjiandao No. 6, Liandao No. 1, Longjiao 06192 ,Longjiao 06-2110,Longjing 20, Longjing 21, Longjing 25, Longjing 26, Sanjiang No. 1 and Suijing No. 8, accounting for 45.16 % ; susceptible(S) varieties(strains ) were Kendao

  20. 枯草芽孢杆菌G87抗菌蛋白对稻瘟病菌和稻恶苗病菌的抑制作用%Inhibition of antifungal protein from Bacillus subtilis G87 to Magnaporthe grisea and Gibberella fujikuroi

    Institute of Scientific and Technical Information of China (English)

    纪兆林; 李娟; 陈夕军; 童蕴慧; 徐敬友

    2012-01-01

    In order to clarify the biological activity of antifungal protein from Bacillus subtilis G87, its inhibition to Magnaporthe grisea and Gibberella fujikuroi was studied. The results showed that the antifungal protein exhibited inhibitory activity on mycelial growth, conidial germination and germ-tube elongation of rice pathogenic fungi mentioned above. At the concentration of 1.20 mg· mL-1 for the antifungal protein, the inhibiting rates were above 60% and 80% against the colony growth and the dry mycelial weight of M. grisea, respectively. In the presence of 2. 40 mg· mL-1 antifungal protein, the inhibiting rates toward the conidial germination and germ-tube elongation of G. fujikuroi were both over 60%. Moreover, the antifungal protein was demonstrated to have a destructive effect on hyphal shape of the two pathogenic fungi, with hyphal cell distortion, protoplasm concentration and leakage, tumescence, cell wall rupture, and collapse. Therefore, B. subtilis G87 antifungal protein has an important antifungal biological activity.%为明确枯草芽孢杆菌(Bacillus subtilis)G87抗菌蛋白的生物活性,采用菌丝生长、分生孢子萌发和芽管伸长抑制的方法,研究其对稻瘟病菌(Magna porthe grisea)和稻恶苗病菌(Gibberella fujikuroi)的抑制作用.结果表明:抗菌蛋白能明显抑制2种病菌菌丝生长、分生孢子萌发和芽管伸长.1.20 mg·mL-1抗菌蛋白对稻瘟病菌菌落直径和菌丝干重的抑制率分别达60%和80%以上; 2.40 mg·mL-1抗菌蛋白对稻恶苗病菌分生孢子萌发和芽管伸长的抑制率均达60%以上.抗菌蛋白还能显著破坏2种病菌菌丝形态,使菌丝细胞畸形膨大、原生质浓缩和外渗、细胞壁破损以及菌体崩溃等.因此,枯草芽孢杆菌G87抗菌蛋白具有重要的抗菌生物活性.

  1. Genome-wide profiling of DNA methylation provides insights into epigenetic regulation of fungal development in a plant pathogenic fungus, Magnaporthe oryzae.

    Science.gov (United States)

    Jeon, Junhyun; Choi, Jaeyoung; Lee, Gir-Won; Park, Sook-Young; Huh, Aram; Dean, Ralph A; Lee, Yong-Hwan

    2015-02-24

    DNA methylation is an important epigenetic modification that regulates development of plants and mammals. To investigate the roles of DNA methylation in fungal development, we profiled genome-wide methylation patterns at single-nucleotide resolution during vegetative growth, asexual reproduction, and infection-related morphogenesis in a model plant pathogenic fungus, Magnaporthe oryzae. We found that DNA methylation occurs in and around genes as well as transposable elements and undergoes global reprogramming during fungal development. Such reprogramming of DNA methylation suggests that it may have acquired new roles other than controlling the proliferation of TEs. Genetic analysis of DNA methyltransferase deletion mutants also indicated that proper reprogramming in methylomes is required for asexual reproduction in the fungus. Furthermore, RNA-seq analysis showed that DNA methylation is associated with transcriptional silencing of transposable elements and transcript abundance of genes in context-dependent manner, reinforcing the role of DNA methylation as a genome defense mechanism. This comprehensive approach suggests that DNA methylation in fungi can be a dynamic epigenetic entity contributing to fungal development and genome defense. Furthermore, our DNA methylomes provide a foundation for future studies exploring this key epigenetic modification in fungal development and pathogenesis.

  2. Structure-function analysis of a CVNH-LysM lectin expressed during plant infection by the rice blast fungus Magnaporthe oryzae.

    Science.gov (United States)

    Koharudin, Leonardus M I; Viscomi, Arturo R; Montanini, Barbara; Kershaw, Michael J; Talbot, Nicholas J; Ottonello, Simone; Gronenborn, Angela M

    2011-05-11

    The rice blast fungus Magnaporthe oryzae's genome encodes a hypothetical protein (MGG_03307) containing a type III CVNH lectin, in which a LysM domain is inserted between individual repeats of a single CVNH domain. At present, no structural or ligand binding data are available for any type III CVNH and functional studies in natural source organisms are scarce. Here, we report NMR solution structure and functional data on MGG_03307. The structure of the CVNH/LysM module revealed that intact and functionally competent CVNH and LysM domains are present. Using NMR titrations, carbohydrate specificities for both domains were determined, and it was found that each domain behaves as an isolated unit without any interdomain communication. Furthermore, live-cell imaging revealed a predominant localization of MGG_03307 within the appressorium, the specialized fungal cell for gaining entry into rice tissue. Our results suggest that MGG_03307 plays a role in the early stages of plant infection. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Multiple translocation of the AVR-Pita effector gene among chromosomes of the rice blast fungus Magnaporthe oryzae and related species.

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    Izumi Chuma

    2011-07-01

    Full Text Available Magnaporthe oryzae is the causal agent of rice blast disease, a devastating problem worldwide. This fungus has caused breakdown of resistance conferred by newly developed commercial cultivars. To address how the rice blast fungus adapts itself to new resistance genes so quickly, we examined chromosomal locations of AVR-Pita, a subtelomeric gene family corresponding to the Pita resistance gene, in various isolates of M. oryzae (including wheat and millet pathogens and its related species. We found that AVR-Pita (AVR-Pita1 and AVR-Pita2 is highly variable in its genome location, occurring in chromosomes 1, 3, 4, 5, 6, 7, and supernumerary chromosomes, particularly in rice-infecting isolates. When expressed in M. oryzae, most of the AVR-Pita homologs could elicit Pita-mediated resistance, even those from non-rice isolates. AVR-Pita was flanked by a retrotransposon, which presumably contributed to its multiple translocation across the genome. On the other hand, family member AVR-Pita3, which lacks avirulence activity, was stably located on chromosome 7 in a vast majority of isolates. These results suggest that the diversification in genome location of AVR-Pita in the rice isolates is a consequence of recognition by Pita in rice. We propose a model that the multiple translocation of AVR-Pita may be associated with its frequent loss and recovery mediated by its transfer among individuals in asexual populations. This model implies that the high mobility of AVR-Pita is a key mechanism accounting for the rapid adaptation toward Pita. Dynamic adaptation of some fungal plant pathogens may be achieved by deletion and recovery of avirulence genes using a population as a unit of adaptation.

  4. Using Network Extracted Ontologies to Identify Novel Genes with Roles in Appressorium Development in the Rice Blast Fungus Magnaporthe oryzae

    Directory of Open Access Journals (Sweden)

    Ryan M. Ames

    2017-01-01

    Full Text Available Magnaporthe oryzae is the causal agent of rice blast disease, the most important infection of rice worldwide. Half the world’s population depends on rice for its primary caloric intake and, as such, rice blast poses a serious threat to food security. The stages of M. oryzae infection are well defined, with the formation of an appressorium, a cell type that allows penetration of the plant cuticle, particularly well studied. However, many of the key pathways and genes involved in this disease stage are yet to be identified. In this study, I have used network-extracted ontologies (NeXOs, hierarchical structures inferred from RNA-Seq data, to identify pathways involved in appressorium development, which in turn highlights novel genes with potential roles in this process. This study illustrates the use of NeXOs for pathway identification from large-scale genomics data and also identifies novel genes with potential roles in disease. The methods presented here will be useful to study disease processes in other pathogenic species and these data represent predictions of novel targets for intervention in M. oryzae.

  5. Homeobox transcription factors are required for conidiation and appressorium development in the rice blast fungus Magnaporthe oryzae.

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    Seryun Kim

    2009-12-01

    Full Text Available The appropriate development of conidia and appressoria is critical in the disease cycle of many fungal pathogens, including Magnaporthe oryzae. A total of eight genes (MoHOX1 to MoHOX8 encoding putative homeobox transcription factors (TFs were identified from the M. oryzae genome. Knockout mutants for each MoHOX gene were obtained via homology-dependent gene replacement. Two mutants, DeltaMohox3 and DeltaMohox5, exhibited no difference to wild-type in growth, conidiation, conidium size, conidial germination, appressorium formation, and pathogenicity. However, the DeltaMohox1 showed a dramatic reduction in hyphal growth and increase in melanin pigmentation, compared to those in wild-type. DeltaMohox4 and DeltaMohox6 showed significantly reduced conidium size and hyphal growth, respectively. DeltaMohox8 formed normal appressoria, but failed in pathogenicity, probably due to defects in the development of penetration peg and invasive growth. It is most notable that asexual reproduction was completely abolished in DeltaMohox2, in which no conidia formed. DeltaMohox2 was still pathogenic through hypha-driven appressoria in a manner similar to that of the wild-type. However, DeltaMohox7 was unable to form appressoria either on conidial germ tubes, or at hyphal tips, being non-pathogenic. These factors indicate that M. oryzae is able to cause foliar disease via hyphal appressorium-mediated penetration, and MoHOX7 is mutually required to drive appressorium formation from hyphae and germ tubes. Transcriptional analyses suggest that the functioning of M. oryzae homeobox TFs is mediated through the regulation of gene expression and is affected by cAMP and Ca(2+ signaling and/or MAPK pathways. The divergent roles of this gene set may help reveal how the genome and regulatory pathways evolved within the rice blast pathogen and close relatives.

  6. Eficiência da disseminação aérea em Pyricularia grisea Efficiency of aerial dissemination of Pyricularia grisea

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    Alfredo Seiiti Urashima

    2007-09-01

    Full Text Available Pyricularia grisea (teleomorfa Magnaporthe grisea é um patógeno que infecta mais de 80 gramíneas. No Brasil ataca importantes culturas como arroz e trigo, causando a brusone. Mais recentemente foi reportada na triticale, cultura alternativa para os produtores de trigo no sul do estado de São Paulo. Um dos principais meios de disseminação da doença é a dispersão aérea embora pouca informação esteja disponível sobre a distância que esses esporos podem atingir a partir de uma determinada fonte de inóculo. O presente trabalho teve o objetivo de avaliar a capacidade de disseminação de P. grisea a partir de um foco inicial, empregando ferramentas moleculares. A presença de clones do patógeno em campos distantes 4, 30 e 1000 metros a partir de um campo infectado sugere que esporos de um determinado foco podem atingir pelo menos essas distâncias.Pyricularia grisea (teleomorph Magnaporthe grisea infects more than 80 gramineous plants. In Brazil, it attacks important crops like rice and wheat causing blast disease. Recently the disease was reported in triticale, an alternative crop to wheat producers in Southern São Paulo state. Airborne conidia are one of the most important way of dissemination, although little reliable information is available on the distance traveled by spores from an inoculum source. The present work aimed to determine by molecular tools the efficiency of aerial dissemination of P. grisea from a known inoculum source. The presence of pathogen clones in fields distant 4, 30 and 1000 meters from an infected field suggested that spores can travel at least these distances.

  7. MoVrp1, a putative verprolin protein, is required for asexual development and infection in the rice blast fungus Magnaporthe oryzae

    Science.gov (United States)

    Huang, Lin; Zhang, Shengpei; Yin, Ziyi; Liu, Muxing; Li, Bing; Zhang, Haifeng; Zheng, Xiaobo; Wang, Ping; Zhang, Zhengguang

    2017-01-01

    Endocytosis is a crucial cellular process in eukaryotic cells which involves clathrin and/or adaptor proteins, lipid kinases, phosphatases and the actin cytoskeleton. Verprolin proteins, such as Vrp1 in Saccharomyces cerevisiae, are conserved family proteins that regulate actin binding and endocytosis. Here, we identified and characterized MoVrp1 as the yeast Vrp1 homolog in Magnaporthe oryzae. Deletion of the MoVRP1 gene resulted in defects in vegetative growth, asexual development, and infection of the host plant. The ∆Movrp1 mutants also exhibited decreased extracellular peroxidase and laccase activities and showed defects in colony pigmentation, hyphal surface hydrophobicity, cell wall integrity, autophagy, endocytosis, and secretion of avirulent effector. Our studies provided new evidences that MoVrp1 involved in actin cytoskeleton is important for growth, morphogenesis, cellular trafficking, and fungal pathogenesis. PMID:28117435

  8. A six-gene phylogeny reveals the evolution of mode of infection in the rice blast fungus and allied species.

    Science.gov (United States)

    Zhang, Ning; Zhao, Shuang; Shen, Qirong

    2011-01-01

    The family Magnaporthaceae contains devastating fungal cereal and grass pathogens, such as Magnaporthe oryzae (rice blast fungus, formerly known as M. grisea), M. poae (summer patch pathogen of turf grasses) and Gaeumannomyces graminis (take-all fungus of various cereals and grasses), which are popular model organisms in fungal biology and host-pathogen interaction studies. Despite their ecological and economic importance, the phylogenetic relationships among the constituent species remain ambiguous due to the lack of convincing morphological characters and paucity of molecular data for the majority of the non-model species in the family. In this study our multilocus phylogeny suggests that both Magnaporthe and Gaeumannomyces are polyphyletic genera. The phylogeny also provides insights into fungal biology and pathogenesis. Magnaporthe oryzae formed a basal clade, while M. poae and M. rhizophila formed another well supported clade with G. incrustans and G. graminis. The basal species infect both root and aerial parts of the plant host, while the aerial infection capacity seems to be lost in the taxa of the latter clade. The phylogeny is corroborated by evolution of the anamorphs and a cAMP-dependent protein kinase (CPKA) gene. Magnaporthe oryzae produces Pyricularia, while taxa in the latter clade all produce Phialophora-like anamorphs. CPKA is present in animals and many fungal lineages with various functions. In M. oryzae CPKA is essential for the formation of functional appressoria for leaf penetration. In root-infecting G. graminis var. tritici and M. poae however only non-functional CPKA homologous pseudogenes were found in their genomes. The study indicates that anamorphic and ecological features are more informative than the teleomorphic characters in defining monophyletic groups among these taxa.

  9. Magnesium Uptake by CorA Transporters Is Essential for Growth, Development and Infection in the Rice Blast Fungus Magnaporthe oryzae.

    Science.gov (United States)

    Reza, Md Hashim; Shah, Hiral; Manjrekar, Johannes; Chattoo, Bharat B

    2016-01-01

    Magnaporthe oryzae, the causative organism of rice blast, infects cereal crops and grasses at various stages of plant development. A comprehensive understanding of its metabolism and the implications on pathogenesis is necessary for countering this devastating crop disease. We present the role of the CorA magnesium transporters, MoAlr2 and MoMnr2, in development and pathogenicity of M. oryzae. The MoALR2 and MoMNR2 genes individually complement the Mg2+ uptake defects of a S. cerevisiae CorA transporter double mutant. MoALR2 and MoMNR2 respond to extracellular Mg2+ and Ca2+ levels and their expression is elevated under Mg2+ scarce conditions. RNA silencing mediated knockdown of MoALR2 (WT+siALR2, Δmnr2+siALR2 and ALR2+MNR2 simultaneous silencing) drastically alters intracellular cation concentrations and sensitivity to metal ions. MoALR2 silencing is detrimental to vegetative growth and surface hydrophobicity of mycelia, and the transformants display loss of cell wall integrity. MoALR2 is required for conidiogenesis and appressorium development, and is essential for infection. Investigation of knockdown transformants reveal low cAMP levels and altered expression of genes encoding proteins involved in MoMps1 cell wall integrity and cAMP MoPmk1 driven MAP Kinase signaling pathways. In contrast to MoALR2 knockdowns, the MoMNR2 deletion (Δmnr2) shows increased sensitivity to CorA inhibitors as well as altered cation sensitivity, but has limited effect on surface hydrophobicity and severity of plant infection. Interestingly, MoALR2 expression is elevated in Δmnr2. Impairment of development and infectivity of knockdown transformants and altered intracellular cation composition suggest that CorA transporters are essential for Mg2+ homeostasis within the cell, and are crucial to maintaining normal gene expression associated with cell structure, signal transduction and surface hydrophobicity in M. oryzae. We suggest that CorA transporters, and especially MoALR2

  10. Preparation of Chitosan nanoparticles and its effect on detached rice leaves infected with Pyricularia grisea.

    Science.gov (United States)

    Manikandan, Appu; Sathiyabama, Muthukrishnan

    2016-03-01

    The aim of the present study was to prepare chitosan nanoparticles to evaluate their effect on protection of rice plants from blast fungus. Nanoparticles were prepared using the ionic gelation method by the interaction of Chitosan and sodium tripolyphosphate. The particle size, polydispersity index, zetapotential and structure was confirmed by DLS, FTIR, TEM and XRD. The Chitosan nanoparticle was evaluated for suppression of rice blast fungus (Pyricularia grisea) under the detached leaf condition. It is evident from our results that chitosan nanoparticle have potential in suppressing blast disease of rice which can be used further under field condition to protect rice plants from the devastating fungus.

  11. Structure-function analysis of Rgs1 in Magnaporthe oryzae: role of DEP domains in subcellular targeting

    National Research Council Canada - National Science Library

    Ramanujam, Ravikrishna; Yishi, Xu; Liu, Hao; Naqvi, Naweed I

    2012-01-01

    Rgs1, a prototypical Regulator of G protein Signaling, negatively modulates the cyclic AMP pathway thereby influencing various aspects of asexual development and pathogenesis in the rice-blast fungus Magnaporthe oryzae...

  12. Eumicetoma por Madurella grisea: relato de caso

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    Maria do Rosário Rodrigues Silva

    1991-03-01

    Full Text Available E relatado um caso de micetoma por Madurella grisea de localização podai em uma mulher do lar. A identificação da amostra foi feita através das características macro e microscópicas do agente em ágar Sabouraud e através da assimilação de açúcares. Este é o quinto caso de micetoma por Madurella grisea relatado no Brasil.One case of mycetoma produced by Madurella grisea localised on the foot of a house wife is reported. The identification of the strain was made through the following features: aspect of the grains, micro e macromorphology in Sabouraud agar and capacity of assimilation of the sugars. This is the fifth case of mycetoma by Madurella grisea reported from Brasil.

  13. Eumycotic mycetoma due to Madurella grisea

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    Walter Belda Júnior

    1989-06-01

    Full Text Available The authors reported one case of eumycotic mycetoma due to Madurella grisea (black grains occurred on the right foot of the patient studied. The structure, microscopic morphology and therapeutic evolution are also studied and reported.

  14. Variant Humicola grisea CBH1.1

    Energy Technology Data Exchange (ETDEWEB)

    Goedegebuur, Frits; Gualfetti, Peter; Mitchinson, Colin; Larenas, Edmund

    2017-05-09

    Disclosed are variants of Humicola grisea CeI7A (CBH1.1), H. jecorina CBH1 variant or S. thermophilium CBH1, nucleic acids encoding the same and methods for producing the same. The variant cellulases have the amino acid sequence of a glycosyl hydrolase of family 7A wherein one or more amino acid residues are substituted.

  15. 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...

  16. Virulence Types of Magnaporthe oryzae to Hybrid Rice in Sichuan, China

    Institute of Scientific and Technical Information of China (English)

    BAI Yu-lian; ZHANG Xue-mei; FENG Hui; JI Hong-li; HUANG Yun; PENG Yun-liang

    2012-01-01

    A total of 638 isolates of rice blast (Magnaporthe oryzae) were isolated in 2002-2009 from different rice varieties in different regions of Sichuan,China and inoculated onto seven rice varieties (Lijiangxintuanheigu,IR24,Minghui 63,Duohui 1,Chenghui 448,Neihui 99-14 and RHR-1) to differentiate the virulence types of the fungus and trace the changes.The virulence to the seven varieties was respectively scored at 1,2,4,8,16,32 and 64.The total scores of individual M.grisea isolates which were the sum of scores infecting differential varieties could,in turn,be used for the nomenclature of the virulence types due to their accordance to the special virulence patterns.The 638 tested isolates were then differentiated into 56 different virulence types.Type 15 virulent to Lijiangxintuanheigu,IR24 and Minghui 63,and Type 127 virulent to all of the seven varieties were the most dominant virulence types respectively with the occurrence frequencies of 15.99% and 15.83%.Type 19 and other seven virulence types were not monitored during 2002-2009.Type 15 was the predominant virulence type in 2002,2003,2004 and 2007,whereas Type 127 had been the most dominant virulence type after 2005 except for the year 2007 when the province underwent severe drought.Five hundred and seven out of the 638 tested isolates were virulent to Minghui 63,and 89.58% of the 384 isolates virulent to either Duohui 1,Chenghui 448 or Neihui 99-14 were virulent to Minghui 63,which indicated the impact of the extensive plantation of hybrid rice Minghui 63 as the restorer line on the virulence evolution of M.oryzae in Sichuan.The virulence pattern of the dominant virulence types suggested that the acquiring of virulence to all the major resistant restorer lines was the main routes of the evolution in virulence of M.oryzae to hybrid rice in Sichuan.The virulence frequencies of the 638 tested isolates to IR24,Minghui 63,Duohui 1,Chenghui 448,Neihui 99-14 and RHR-1 were respectively 74.6%,79.5%,73.8%,37

  17. Virulence Types of Magnaporthe oryzae to Hybrid Rice in Sichuan, China

    Directory of Open Access Journals (Sweden)

    Yu-lian BAI

    2012-12-01

    Full Text Available A total of 638 isolates of rice blast (Magnaporthe oryzae were isolated in 2002–2009 from different rice varieties in different regions of Sichuan, China and inoculated onto seven rice varieties (Lijiangxintuanheigu, IR24, Minghui 63, Duohui 1, Chenghui 448, Neihui 99-14 and RHR-1 to differentiate the virulence types of the fungus and trace the changes. The virulence to the seven varieties was respectively scored at 1, 2, 4, 8, 16, 32 and 64. The total scores of individual M. grisea isolates which were the sum of scores infecting differential varieties could, in turn, be used for the nomenclature of the virulence types due to their accordance to the special virulence patterns. The 638 tested isolates were then differentiated into 56 different virulence types. Type 15 virulent to Lijiangxintuanheigu, IR24 and Minghui 63, and Type 127 virulent to all of the seven varieties were the most dominant virulence types respectively with the occurrence frequencies of 15.99% and 15.83%. Type 19 and other seven virulence types were not monitored during 2002–2009. Type 15 was the predominant virulence type in 2002, 2003, 2004 and 2007, whereas Type 127 had been the most dominant virulence type after 2005 except for the year 2007 when the province underwent severe drought. Five hundred and seven out of the 638 tested isolates were virulent to Minghui 63, and 89.58% of the 384 isolates virulent to either Duohui 1, Chenghui 448 or Neihui 99-14 were virulent to Minghui 63, which indicated the impact of the extensive plantation of hybrid rice Minghui 63 as the restorer line on the virulence evolution of M. oryzae in Sichuan. The virulence pattern of the dominant virulence types suggested that the acquiring of virulence to all the major resistant restorer lines was the main routes of the evolution in virulence of M. oryzae to hybrid rice in Sichuan. The virulence frequencies of the 638 tested isolates to IR24, Minghui 63, Duohui 1, Chenghui 448, Neihui 99

  18. Activities of defense related enzymes induced by benzothiadiazole in rice to blast fungus

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Pretreatment of rice seedlings by foliar spraying with benzothiadiazole (BTH) could induce systematic acquired resistance (SAR) against blast (Magnaporthe grisea) and bacterial leaf blight (Xanthomonas oryzae pv. oryzae) diseases. To elucidate the physiological and biochemical mechanisms of the SAR induced by BTH, we analyzed the changes in activities of phenylalanine ammonia lyase (PAL), cinnamylalcohol dehydrogenase (CAD), peroxidase(POD), lipoxygenase(LOX),β 1,3 glucanase,and chitinase in rice seedlings of susceptible variety pretreated with BTH and challenged by M. grisea.

  19. The plant pathogenic fungus Gaeumannomyces graminis var. tritici improves bacterial growth and triggers early gene regulations in the biocontrol strain Pseudomonas fluorescens Pf29Arp.

    Science.gov (United States)

    Barret, M; Frey-Klett, P; Boutin, M; Guillerm-Erckelboudt, A-Y; Martin, F; Guillot, L; Sarniguet, A

    2009-01-01

    In soil, some antagonistic rhizobacteria contribute to reduce root diseases caused by phytopathogenic fungi. Direct modes of action of these bacteria have been largely explored; however, commensal interaction also takes place between these microorganisms and little is known about the influence of filamentous fungi on bacteria. An in vitro confrontation bioassay between the pathogenic fungus Gaeumannomyces graminis var. tritici (Ggt) and the biocontrol bacterial strain Pseudomonas fluorescens Pf29Arp was set up to analyse bacterial transcriptional changes induced by the fungal mycelium at three time-points of the interaction before cell contact and up until contact. For this, a Pf29Arp shotgun DNA microarray was constructed. Specifity of Ggt effect was assessed in comparison with one of two other filamentous fungi, Laccaria bicolor and Magnaporthe grisea. During a commensal interaction, Ggt increased the growth rate of Pf29Arp. Before contact, Ggt induced bacterial genes involved in mycelium colonization. At contact, genes encoding protein of stress response and a patatin-like protein were up-regulated. Among all the bacterial genes identified, xseB was specifically up-regulated at contact by Ggt but down-regulated by the other fungi. Data showed that the bacterium sensed the presence of the fungus early, but the main gene alteration occurred during bacterial-fungal cell contact.

  20. Eumicetoma de grãos pretos por Madurella grisea: registro de dois casos Eumycotic mycetoma of black grains caused by Madurella grisea: report of two cases

    Directory of Open Access Journals (Sweden)

    Luís Antonio de Paula Machado

    1992-12-01

    Full Text Available Os Autores registram dois casos de eumicetoma de grãos pretos, com localização podal, procedentes da Bahia, provocados por Madurella grisea Mackinnon et al., 1949. São estudadas a estrutura dos grãos, bem como as características micromorfológicas do fungo em vida saprofítica. Acreditam os Autores que estas observações correspondem ao sétimo e oitavo casos registrados na literatura do país, provocadas por este fungo. Os Autores consideram nomen dubium ou nomina confusa as seguintes espécies de Madurella: M. ramiroi, M. oswaldoi, M. bovoi, M. tozeuri, M. mansonii, M. brumpti, M. reynieri, M. americana, M. lackawanna e M. ikedae, o mesmo ocorrendo com a chamada Rubromadurella mycetomi. As únicas espécies válidas são Madurella mycetomatis McGinnis, 1980 (=Madurella mycetomi Brumpt, 1905 e Madurella grisea Mackinnon et al., 1949. Nos dois casos registrados o tratamento com itraconazol, por um período de 3 meses não fez regredir as lesões, havendo ligeira melhora clínica.Two cases of black grains eumycotic mycetoma, occurring on a foot, are reported. Both proceeded from the State of Bahia (Brazil, and in both the etiologic agent was Madurella grisea Mackinnon et al., 1949. The grains structure as well as the micromorphologic characteristics of the fungus in saprophytic life were studied. It is the Author's belief that these observations correspond to the 7th and 8th cases reported in the Brazilian medical literature. The Authors do consider the following Madurella species as nomen dubium or nomina confusa: M. ramiroi, M. oswaldoi, M. bovoi, M. tozeuri, M. mansonii, M. brumpti, M. reynieri, M. americana, M. lackawanna e M. ikedae and the same for Rubromadurella mycetomi. The only valid species must be Madurella mycetomatis McGinnis, 1980 (=Madurella mycetomi Brumpt, 1905 and Madurella grisea Mackinnon et al., 1949. Treatment with itraconazole in both reported cases, for a 3 month duration, did not produce any regression of the

  1. Construction of Metagenomic Library from Soil and Screening of Clones with Antagonism to the Rice Blast Fungus (Magnaporthe grisea)%土壤宏基因组文库的构建及拮抗稻瘟菌克隆子的筛选

    Institute of Scientific and Technical Information of China (English)

    陈旭玉; 周亚奎; 余贤美; 林春花; 郑服丛

    2009-01-01

    从橡胶林土壤中提取微生物总DNA,用Pst Ⅰ酶切后,酶切液与pBluescriptKS+载体连接转入大肠杆菌,构建了包含7 680个克隆子的宏基因组文库,76.2%的质粒含有外源DNA,插入片段的平均大小为4.3kb,DNA文库的容量为32.25MB.首先用序列筛选方法对土壤宏基因组文库进行筛选,共得到11个克隆子,通过对11个克隆子进行功能筛选(复筛),发现克隆子JKDL-1和JKDL-2对稻瘟菌有明显抑制作用,其余的9个克隆子对稻瘟菌没有明显活性.具有拮抗作用的克隆子通过NCBI的Blastx分析,发现JKDL-1和JKDL-2分别与柄杆菌属(Caulobacter sp. K31)和布克氏菌属(Burkholderia ambifaria MC40-6)有75%和77%的同源性,初步预测其功能为组氨酸激酶(GAF sensor hybrid histidine kinase)和乙酰辅酶A乙酰转移酶(acetyl-CoA acetyltransferases).

  2. Investigation of the biological roles of autophagy in appressorium morphogenesis in Magnaporthe oryzae

    Institute of Scientific and Technical Information of China (English)

    Xiao-hong LIU; Fu-cheng LIN

    2008-01-01

    Magnaporthe oryzae has been used as a primary model organism for investigating fungus-plant interaction. Many researches focused on molecular mechanisms of appressorium formation to restrain this fungal pathogen. Autophagy is a very high conserved process in eukaryotic cells. Recently, autophagy has been considered as a key process in development and differentiation in M. oryzae. In this report, we present and discuss the current state of our knowledge on gene expression in appressorium formation and the progress in autophagy of rice blast fungi.

  3. Esporulação de Pyricularia grisea em diferentes meios de cultura e regimes de luz Sporulation of Pyricularia grisea on different culture media and light regimes

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Antunes da Cruz

    2009-08-01

    Full Text Available Diferentes fatores influenciam o crescimento e a esporulação dos fungos, tais como: composição do meio de cultivo, temperatura e luz. O objetivo do trabalho foi determinar o melhor meio de cultivo e regime de luz para a esporulação de Pyricularia grisea. Um isolado deste, obtido da cultivar de trigo 'BRS 194', foi repicado por disco micelial em oito meios de cultivo (farinha integral de arroz, aveia, centeio, cevada, trigo, triticale; BSA e extrato de tomate e submetido a três regimes de luz (escuro, fotoperíodo de 12h e luz contínua. As placas permaneceram por 10 dias, em câmara de crescimento sob temperatura de 23-25°C. Em seguida, o número de conídios foi determinado em câmara de Neubauer. O meio de cultivo à base de farinha integral de trigo propiciou a maior esporulação do fungo em todos os regimes de luz, e a maior esporulação ocorreu em regime de luz contínua para todos os meios de cultivos testados. Os meios de arroz e BSA propiciaram uma menor produção de conídios pelo fungo.A set of conditions is necessary for the growth and sporulation of fungi, particularly the composition of culture media, temperature and light. The objective of this research was to determine the ideal culture medium and light regime for the sporulation of P. grisea. Micelial discs of an isolate, obtained from cultivar 'BRS 194' of wheat, were transferred to eight culture media (rice wholemeal, oat, rye, barley, wheat, triticale, PSA and tomato sauce and kept in the dark, under continuous light and 12h of light. In a growing chamber, for 10 days at 23-25°C. Then, the number of conidia was determined in a Neubauer chamber. The higher sporulation, regardless of light regime, was observed on wheat wholemeal culture medium. The continuous light provided higher sporulation this fungus in all culture medium. The lowest production of conidia was observed on rice wholemeal and PSA culture media.

  4. Registration of 42 blast resistant medium grain rice genetic stocks with suitable agronomic, yield, milling yield, and grain characteristics

    Science.gov (United States)

    Rice blast disease caused by the filamentous ascomycete fungus Magnaporthe oryzae Cav. [Magnaporthe grisea (Herbert) Barr.] is one of the most threatening rice diseases in the southern United States. In the present study, 42 rice (Oryza sativa L.) blast resistant genetic stocks (GSOR102501 to 201542...

  5. Antinociceptive and Anti-Inflammatory Effects of Octacosanol from the Leaves of Sabicea grisea var. grisea in Mice

    Directory of Open Access Journals (Sweden)

    Emiliano Barreto

    2012-02-01

    Full Text Available Sabicea species are used in the Amazon for treatment of fever and malaria, which suggests that its chemical constituents may have some effect on pain and inflammation. Phytochemical analysis of the hexane fraction obtained from the crude ethanol extract from Sabicea grisea var. grisea Cham. & Schltdl (Rubiaceae, an endemic plant in Brazil, resulted in the isolation of octacosanol. This study investigated the antinociceptive and anti-inflammatory effects of the octacosanol in different experimental models. The crude ethanolic extract and hexane fraction obtained from the leaves of S. grisea produced an inhibition of acetic acid-induced pain. Moreover, octacosanol isolated from the hexane fraction produced a significant inhibition of pain response elicited by acetic acid. Pre-treatment with yohimbine, an alpha 2-adrenergic receptor antagonist, notably reversed the antinociceptive activity induced by octacosanol in the abdominal constriction test. Furthermore, mice treated with octacosanol did not exhibit any behavioral alteration during the hot plate and rota-rod tests, indicating non-participation of the supraspinal components in the modulation of pain by octacosanol with no motor abnormality. In the formalin test, octacosanol did not inhibit the licking time in first phase (neurogenic pain, but significantly inhibited the licking time in second phase (inflammatory pain of mice. The anti-inflammatory effect of octacosanol was evaluated using carrageenan-induced pleurisy. The octacosanol significantly reduced the total leukocyte count and neutrophils influx, as well as TNF-α levels in the carrageenan-induced pleurisy. This study revealed that the mechanism responsible for the antinociceptive and anti-inflammatory effects of the octacosanol appears to be partly associated with an inhibition of alpha 2-adrenergic transmission and an inhibition of pathways dependent on pro-inflammatory cytokines. Finally, these results demonstrated that the

  6. Screening of sporogenous medium for Pyricularia grisea (Cooke) Sacc%灰梨孢菌产孢培养基筛选

    Institute of Scientific and Technical Information of China (English)

    霍秀娟; 李朝生; 韩美丽; 陆荣生

    2012-01-01

    [Objective]To provide technical support for Pyricularia grisea research, common effective sporogenous medium with simple, suitable operation was screened in the present experiment. [ Method ] Six Pyricularia grisea isolates obtained from rice, banana, and crab-grass were inoculated on nine kinds of media, e.g., C. communis, sorghum grain and barleycorn, etc. Effects of different media on sporulation quantity of Pyricularia grisea were investigated, and pathogenicity of Pyricularia grisea as assayed in C. communis media. [Result]Sorghum grain, barleycorn and C. communis media pronouncedly stimulated the sporulation in six strains with C. communis bested. Compared to commonly -used sorghum grain medium, spores cultured in C. communis media had similar pathogenicity towards rice and banana. Magna-porthe oryzae and banana blast strains in C. communis medium could be preserved at 4℃ for two years. [Conclusion]C. communis media was found to be the most suitable media for spores of Pyricularia grisea, and it was also found to conserve Pyricularia grisea.%[目的]筛选操作方法简便、产孢效果好、适宜于大多数灰梨孢菌的产孢培养基,为灰梨孢菌研究提供一定的技术支持.[方法]从水稻、香蕉和杂草马唐上分离获得6个灰梨孢菌菌株,接种于紫花鸭趾草、高粱粒和大麦粒等9种培养基上,测定不同培养基对灰梨孢菌产孢量的影响,并比较分析紫花鸭趾草培养基对病菌致病力的影响.[结果]高粱粒、大麦粒和紫花鸭趾草培养基对6个菌株孢子形成均有明显的促进作用,以紫花鸭趾草培养基的促进作用最明显.与常用的高粱粒培养基相比,6个菌株在紫花鸭趾草培养基上形成的病菌分生孢子对香蕉和水稻的致病力没有明显差异.在4℃冰箱中,用紫花鸭趾草培养基保存蕉瘟病和稻瘟病菌菌种,两年后病菌仍具有生活力.[结论]紫花鸭趾草培养基是适宜于灰梨孢菌分生孢子形成的理想

  7. Gene Expression Proifling Related to Hyphal Growth in a Temperature- Sensitive Mutant ofMagnaporthe oryzae

    Institute of Scientific and Technical Information of China (English)

    LI Xue-song; XU Fei; WANG Hong-kai; and LIN Fu-cheng

    2013-01-01

    The rice blast, caused by fungusMagnaporthe oryzae, is a major constraint to the world food security. Hyphal growth is the foundation of fungal development and proliferation of fungi. To investigate genes involved in hyphal growth of this fungus, digital gene expression tag proifling was used to compare a previously generated temperature-sensitive mutant which defect at hyphae growth and reduction on pathogenicity, with its related wildtype strain. 416 genes were detected as differential expression, 178 of which were speciifcally expressed in Guy-11 but down-regulated expression in the mutant. Functional classiifcation analysis revealed the phenotype mutation may be mainly caused by a defection in translational and vacuole-related processes. The results and the protocol used will improve our knowledge on morphogenesis and promote the further study onM. oryzae pathogenesis.

  8. Toward understanding of rice innate immunity against Magnaporthe oryzae.

    Science.gov (United States)

    Azizi, P; Rafii, M Y; Abdullah, S N A; Nejat, N; Maziah, M; Hanafi, M M; Latif, M A; Sahebi, M

    2016-01-01

    The blast fungus, Magnaporthe oryzae, causes serious disease on a wide variety of grasses including rice, wheat and barley. The recognition of pathogens is an amazing ability of plants including strategies for displacing virulence effectors through the adaption of both conserved and variable pathogen elicitors. The pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) and effector-triggered immunity (ETI) were reported as two main innate immune responses in plants, where PTI gives basal resistance and ETI confers durable resistance. The PTI consists of extracellular surface receptors that are able to recognize PAMPs. PAMPs detect microbial features such as fungal chitin that complete a vital function during the organism's life. In contrast, ETI is mediated by intracellular receptor molecules containing nucleotide-binding (NB) and leucine rich repeat (LRR) domains that specifically recognize effector proteins produced by the pathogen. To enhance crop resistance, understanding the host resistance mechanisms against pathogen infection strategies and having a deeper knowledge of innate immunity system are essential. This review summarizes the recent advances on the molecular mechanism of innate immunity systems of rice against M. oryzae. The discussion will be centered on the latest success reported in plant-pathogen interactions and integrated defense responses in rice.

  9. Nail Fungus

    Science.gov (United States)

    ... problems, a weakened immune system or, in children, Down syndrome A severe case of nail fungus can be ... possibly effective in treating nail fungus, but more study is needed. ... and file down thickened areas. Wear socks that absorb sweat. Fabrics ...

  10. Comparative Analysis of the Korean Population of Magnaporthe oryzae by Multilocus Microsatellite Typing

    Directory of Open Access Journals (Sweden)

    Jaehyuk Choi

    2013-12-01

    Full Text Available Rice blast fungus, Magnaporthe oryzae, inflicts serious damage to global rice production. Due to high variability of this fungal pathogen, resistance of newly-released rice cultivars is easily broken down. To understand the population structure of M. oryzae, we analyzed the genetic diversity of the Korean population using multilocus microsatellite typing. Eleven microsatellite markers were applied to the population of 190 rice isolates which had been collected in Korea for two decades since the 1980’s. Average values of gene diversity and allele frequency were 0.412 and 6.5, respectively. Comparative analysis of the digitized allele information revealed that the Korean population exhibited a similar level of allele diversity to the integrated diversity of the world populations, suggesting a particularly high diversity of the Korean population. Therefore, these microsatellite markers and the comprehensive collection of field isolates will be useful genetic resources to identify the genetic diversity of M. oryzae population.

  11. Magnaporthe oryzae MTP1 gene encodes a type Ⅲ transmembrane protein involved in conidiation and conidial germination

    Institute of Scientific and Technical Information of China (English)

    Qin LU; Jian-ping LU; Xiao-dong LI; Xiao-hong LIU; Hang MIN; Fu-cheng LIN

    2008-01-01

    In this study the MTP1 gene, encoding a type Ⅲ integral transmembrane protein, was isolated fi'om the rice blast fungus Magnaporthe oryzae. The Mtpl protein is 520 amino acids long and is comparable to the Ytpl protein of Saccharomyces cerevisiae with 46% sequence similarity. Prediction programs and MTP1-GFP (green fluorescent protein) fusion expression results indicate that Mtpl is a protein located at several membranes in the cytoplasm. The functions of the MTP1 gene in the growth and development of the fungus were studied using an MTP1 gene knockout mutant. The MTP1 gene was primarily ex-pressed at the hyphal and conidial stages and is necessary for conidiation and conidial germination, but is not required for patho-genicity. The △mtpl mutant grew more efficiently than the wild type strain on non-fermentable carbon sources, implying that the MTP1 gene has a unique role in respiratory growth and carbon source use.

  12. Perspectivas del uso de bacterias rizosféricas en el control de Pyricularia grisea (Cooke Sacc. en el cultivo del arroz (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Yanelis Acebo Guerrero

    2011-04-01

    .  Among fungi, Pyricularia grisea, the blast fungus is responsible for up to 100% of reduction in yields, being the blast the most important rice disease in Latin America. To control this pathogen, a strategy of sustainable agriculture might be developed, combining accurately chemical and biological products. PGPB based bioproducts have been considered as an eco-friendly alternative, which favours environment preservation. This work was aimed to approach the current status and outlook of the use of rhizobacteria in the biocontrol of Pyricularia grisea on rice. Main diseases attacking rice, most beneficial PGPB and its mechanisms of action will be discussed too in this review.Key words: Plant growth promoting bacteria, rice, biological control, blast fungus.

  13. Enhanced disease resistance and drought tolerance in transgenic rice plants overexpressing protein elicitors from Magnaporthe oryzae.

    Science.gov (United States)

    Wang, Zhenzhen; Han, Qiang; Zi, Qian; Lv, Shun; Qiu, Dewen; Zeng, Hongmei

    2017-01-01

    Exogenous application of the protein elicitors MoHrip1 and MoHrip2, which were isolated from the pathogenic fungus Magnaporthe oryzae (M. oryzae), was previously shown to induce a hypersensitive response in tobacco and to enhance resistance to rice blast. In this work, we successfully transformed rice with the mohrip1 and mohrip2 genes separately. The MoHrip1 and MoHrip2 transgenic rice plants displayed higher resistance to rice blast and stronger tolerance to drought stress than wild-type (WT) rice and the vector-control pCXUN rice. The expression of salicylic acid (SA)- and abscisic acid (ABA)-related genes was also increased, suggesting that these two elicitors may trigger SA signaling to protect the rice from damage during pathogen infection and regulate the ABA content to increase drought tolerance in transgenic rice. Trypan blue staining indicated that expressing MoHrip1 and MoHrip2 in rice plants inhibited hyphal growth of the rice blast fungus. Relative water content (RWC), water usage efficiency (WUE) and water loss rate (WLR) were measured to confirm the high capacity for water retention in transgenic rice. The MoHrip1 and MoHrip2 transgenic rice also exhibited enhanced agronomic traits such as increased plant height and tiller number.

  14. Systematic characterization of the peroxidase gene family provides new insights into fungal pathogenicity in Magnaporthe oryzae.

    Science.gov (United States)

    Mir, Albely Afifa; Park, Sook-Young; Abu Sadat, Md; Kim, Seongbeom; Choi, Jaeyoung; Jeon, Junhyun; Lee, Yong-Hwan

    2015-07-02

    Fungal pathogens have evolved antioxidant defense against reactive oxygen species produced as a part of host innate immunity. Recent studies proposed peroxidases as components of antioxidant defense system. However, the role of fungal peroxidases during interaction with host plants has not been explored at the genomic level. Here, we systematically identified peroxidase genes and analyzed their impact on fungal pathogenesis in a model plant pathogenic fungus, Magnaporthe oryzae. Phylogeny reconstruction placed 27 putative peroxidase genes into 15 clades. Expression profiles showed that majority of them are responsive to in planta condition and in vitro H2O2. Our analysis of individual deletion mutants for seven selected genes including MoPRX1 revealed that these genes contribute to fungal development and/or pathogenesis. We identified significant and positive correlations among sensitivity to H2O2, peroxidase activity and fungal pathogenicity. In-depth analysis of MoPRX1 demonstrated that it is a functional ortholog of thioredoxin peroxidase in Saccharomyces cerevisiae and is required for detoxification of the oxidative burst within host cells. Transcriptional profiling of other peroxidases in ΔMoprx1 suggested interwoven nature of the peroxidase-mediated antioxidant defense system. The results from this study provide insight into the infection strategy built on evolutionarily conserved peroxidases in the rice blast fungus.

  15. HUBUNAGN KEMAMPUAN PERGANTIAN INANG DENGAN PLASTISITAS GENETIKA PADA CENDAWAN BLAS PADI (PYRICULARIA GRISEA)

    OpenAIRE

    Sri Listiyowati; Utut Widyastuti; Gayuh Rahayu; Alex Hartana; Muhammad Jusuf

    2009-01-01

    The Digitaria ciliaris, wild grass grown around rice field, was a host for Pyricularia grisea (Cooke) Sacc., the fungi caused blast disease of rice. This fungi have a specific mechanism to regenerate new genetic variation in its life cycle. The aim of this research is to study the relation between the ability of the fungi to infect different species of host with its genetic plasticity. It was used three SCAR molecular markers Cut1, Pwl 1 and Erg2. P. grisea isolates (Dc4J1) originated from ...

  16. Over-Expression of the Pikh Gene with a CaMV 35S Promoter Leads to Improved Blast Disease (Magnaporthe oryzae) Tolerance in Rice

    OpenAIRE

    2016-01-01

    Magnaporthe oryzae is a rice blast fungus and plant pathogen that causes a serious rice disease and, therefore, poses a threat to the world's second most important food security crop. Plant transformation technology has become an adaptable system for cultivar improvement and to functionally analyze genes in plants. The objective of this study was to determine the effects (through over-expressing and using the CaMV 35S promoter) of Pikh on MR219 resistance because it is a rice variety that is ...

  17. A Rare Presentation of Concurrent Scedosporium apiospermum and Madurella grisea Eumycetoma in an Immunocompetent Host

    Directory of Open Access Journals (Sweden)

    Vivek Gulati

    2012-01-01

    Full Text Available Mycetoma is a disfiguring, chronic granulomatous infection which affects the skin and the underlying subcutaneous tissue. We present an atypical case of recurrent mycetoma without ulceration, in a 35-year-old immunocompetent male caused by Scedosporium apiospermum sensu stricto and Madurella grisea, occurring at two separate anatomical sites.

  18. Functional genomics in the rice blast fungus to unravel the fungal pathogenicity

    Institute of Scientific and Technical Information of China (English)

    Junhyun JEON; Jaehyuk CHOI; Jongsun PARK; Yong-Hwan LEE

    2008-01-01

    A rapidly growing number of successful genome sequencing projects in plant pathogenic fungi greatly increase the demands for tools and methodologies to study fungal pathogenicity at genomic scale. Magnaporthe oryzae is an economically important plant pathogenic fungus whose genome is fully sequenced. Recently we have reported the development and application of functional genomics platform technologies in M. oryzae. This model approach would have many practical ramifications in design and implementation of upcoming functional genomics studies of filamentous fungi aimed at understanding fungal pathogenicity.

  19. An expedited method for isolation of DNA for PCR from Magnaporthe oryzae stored on filter paper

    Institute of Scientific and Technical Information of China (English)

    Yulin; Jia; Yeshi; A.; Wamishe; Bo; Zhou

    2014-01-01

    The fungus Magnaporthe oryzae is the causal agent of a wide range of cereal diseases. For long-term preservation, the fungus is grown and stored desiccated on filter papers at –20 °C.Inoculated filter papers are cut into pieces of 0.5–1.0 cm diameter prior to storage. In the present study, a fast(11 min) and simple method of preparing DNA suitable for amplifying avirulence genes of M. oryzae by polymerase chain reaction(PCR) was developed. A piece of filter paper containing the fungus was removed from a glass bottle and placed in a 0.2 mL Eppendorf tube containing 100 μL 10 × TE. The suspension was heated for 10 min at 95 °C in a PCR machine. The tube was then centrifuged for 1 min at 3000 r min-1. One μL of 10 × TE solution containing DNA was used for PCR. A total of 28 samples were PCR tested. As a positive control, fungal DNA was extracted using a conventional DNA preparation method. DNA samples obtained from both methods were stored at 4 °C. PCR was performed with DNA on the preparation day and after 4, 8,10, and 18 days of refrigerated storage. In four samples, samples 12, 13, 14, and 28, AVR-Pi9 failed to be amplified. These four samples were tested with a different set of primers for AVR-Pi9, and for AVR-Pita1, confirming that the quality of the samples was insufficient for PCR. Overall, for nearly 90%(24/28) of the samples, the quality of the DNA prepared directly from the fungus on filter paper appeared suitable for a rapid survey of genetic identity of the rice blast fungus by PCR.This method will be useful and effective for reducing cost and time and could readily be adopted worldwide for analysis of M. oryzae and possibly other fungi.

  20. An expedited method for isolation of DNA for PCR from Magnaporthe oryzae stored on filter paper

    Directory of Open Access Journals (Sweden)

    Yulin Jia

    2014-10-01

    Full Text Available The fungus Magnaporthe oryzae is the causal agent of a wide range of cereal diseases. For long-term preservation, the fungus is grown and stored desiccated on filter papers at –20 °C. Inoculated filter papers are cut into pieces of 0.5–1.0 cm diameter prior to storage. In the present study, a fast (11 min and simple method of preparing DNA suitable for amplifying avirulence genes of M. oryzae by polymerase chain reaction (PCR was developed. A piece of filter paper containing the fungus was removed from a glass bottle and placed in a 0.2 mL Eppendorf tube containing 100 μL 10 × TE. The suspension was heated for 10 min at 95 °C in a PCR machine. The tube was then centrifuged for 1 min at 3000 r min− 1. One μL of 10 × TE solution containing DNA was used for PCR. A total of 28 samples were PCR tested. As a positive control, fungal DNA was extracted using a conventional DNA preparation method. DNA samples obtained from both methods were stored at 4 °C. PCR was performed with DNA on the preparation day and after 4, 8, 10, and 18 days of refrigerated storage. In four samples, samples 12, 13, 14, and 28, AVR-Pi9 failed to be amplified. These four samples were tested with a different set of primers for AVR-Pi9, and for AVR-Pita1, confirming that the quality of the samples was insufficient for PCR. Overall, for nearly 90% (24/28 of the samples, the quality of the DNA prepared directly from the fungus on filter paper appeared suitable for a rapid survey of genetic identity of the rice blast fungus by PCR. This method will be useful and effective for reducing cost and time and could readily be adopted worldwide for analysis of M. oryzae and possibly other fungi.

  1. Exogenous superoxide dismutase may lose its antidotal ability on rice leaves

    Science.gov (United States)

    Leaf diffusates of the resistant rice cultivars suppressed spore germination of blast fungus (Magnaporthe grisea). Bovine Cu-Zn superoxide dismutase (SOD) added to the diffusate abolished its toxicity. However, the enzyme added to the inoculum did not affect the toxicity of the diffusate. Even the s...

  2. The cAMP Signaling and MAP Kinase Pathways in Plant Pathogenic Fungi

    NARCIS (Netherlands)

    Mehrabi, R.; Zhao, X.; Kim, Y.; Xu, J.R.

    2009-01-01

    The key components of the well conserved cyclic AMP signaling and MAP kinase pathways have been functionally characterized in the corn smut Ustilago maydis, rice blast fungus Magnaporthe grisea, and a few other fungal pathogens. In general, the cAMP signaling and the MAP kinase cascade homologous to

  3. Fungus Amongus

    Science.gov (United States)

    Wakeley, Deidra

    2005-01-01

    This role-playing simulation is designed to help teach middle level students about the typical lifecycle of a fungus. In this interactive simulation, students assume the roles of fungi, spores, living and dead organisms, bacteria, and rain. As they move around a playing field collecting food and water chips, they discover how the organisms…

  4. A simple and effective method for total RNA isolation of appressoria in Magnaporthe oryzae

    Institute of Scientific and Technical Information of China (English)

    Tongbao LIU; Jian-ping LU; Xiao-hong LIU; Hang MIN; Fu-cheng LIN

    2008-01-01

    Appressorium formation is an important event in establishing a successful interaction between the rice blast fungus, Magnaporthe oryzae, and its host plant, rice. An understanding of molecular events occurring in appressorium differentiation will give new strategies to control rice blast. A quick and reliable method to extract total RNA from appressorium is essential for studying gene expression during appressorium formation and its mechanism. We found that duplicate film is an efficient substratum for appressorium formation, even when inoculated with high density conidia. When inoculated with conidia at 1×106ml-1, the percentages of conidium germination and appressorium formation were (97.98±0.67)% and (97.88±0.45)%, respectively. We applied Trizol before appressorium collection for total RNA isolation, and as much as 113.6 pg total RNA was isolated from the mature appressoria at 24 h after inoculation. Functional analysis of two genes, MNH6 and MgATG1, isolated from the cDNA subtractive library, revealed that the quantity of RNA was good enough to construct a cDNA (complementary DNA) library or a cDNA subtractive library. This method may be also applicable for the appressorium RNA isolation of other pathogenic fungi in which conidia differentiate into appressoria in the early stages of host infection.

  5. The 2NS Translocation from Aegilops ventricosa Confers Resistance to the Triticum Pathotype of Magnaporthe oryzae

    Science.gov (United States)

    Cruz, C.D.; Peterson, G.L.; Bockus, W.W.; Kankanala, P.; Dubcovsky, J.; Jordan, K.W.; Akhunov, E.; Chumley, F.; Baldelomar, F.D.; Valent, B.

    2016-01-01

    Wheat blast is a serious disease caused by the fungus Magnaporthe oryzae (Triticum pathotype) (MoT). The objective of this study was to determine the effect of the 2NS translocation from Aegilops ventricosa (Zhuk.) Chennav on wheat head and leaf blast resistance. Disease phenotyping experiments were conducted in growth chamber, greenhouse, and field environments. Among 418 cultivars of wheat (Triticum aestivum L.), those with 2NS had 50.4 to 72.3% less head blast than those without 2NS when inoculated with an older MoT isolate under growth chamber conditions. When inoculated with recently collected isolates, cultivars with 2NS had 64.0 to 80.5% less head blast. Under greenhouse conditions when lines were inoculated with an older MoT isolate, those with 2NS had a significant head blast reduction. With newer isolates, not all lines with 2NS showed a significant reduction in head blast, suggesting that the genetic background and/or environment may influence the expression of any resistance conferred by 2NS. However, when near-isogenic lines (NILs) with and without 2NS were planted in the field, there was strong evidence that 2NS conferred resistance to head blast. Results from foliar inoculations suggest that the resistance to head infection that is imparted by the 2NS translocation does not confer resistance to foliar disease. In conclusion, the 2NS translocation was associated with significant reductions in head blast in both spring and winter wheat.

  6. Endocytosis in the plant-pathogenic fungus Ustilago maydis.

    Science.gov (United States)

    Fuchs, U; Steinberg, G

    2005-10-01

    Filamentous fungi are an important group of tip-growing organisms, which include numerous plant pathogens such as Magnaporthe grisea and Ustilago maydis. Despite their ecological and economical relevance, we are just beginning to unravel the importance of endocytosis in filamentous fungi. Most evidence for endocytosis in filamentous fungi is based on the use of endocytic tracer dyes that are taken up into the cell and delivered to the vacuole. Moreover, genomewide screening for candidate genes in Neurospora crassa and U. maydis confirmed the presence of most components of the endocytic machinery, indicating that endocytosis participates in filamentous growth. Indeed, it was shown that in U. maydis early endosomes cluster at sites of growth, where they support morphogenesis and polar growth, most likely via endosome-based membrane recycling. In humans, such recycling processes to the plasma membrane involve small GTPases such as Rab4. A homologue of this protein is encoded in the genome of U. maydis but is absent from the yeast Saccharomyces cerevisiae, suggesting that Rab4-mediated recycling is important for filamentous growth. Furthermore, human Rab4 regulates traffic of early endosomes along microtubules, and a similar microtubule-based transport is described for U. maydis. These observations suggest that Rab4-like GTPases might regulate endosome- and microtubule-based recycling during tip growth of filamentous fungi.

  7. Development of a warning system for wheat blast caused by Pyricularia grisea Desenvolvimento de sistema de previsão de brusome causada por Pyricularia grisea

    Directory of Open Access Journals (Sweden)

    Cinara Araújo de Andrade Cardoso

    2008-09-01

    Full Text Available Wheat (Triticum aestivum L. blast caused by Pyricularia grisea is a new disease in Brazil and no resistant cultivars are available. The interactions between temperature and wetness durations have been used in many early warning systems. Hence, growth chamber experiments to assess the effect of different temperatures (10, 15, 20, 25, 30 and 35ºC and the duration of spike-wetness (0, 5, 10, 15, 20, 25, 30, 35 and 40 hours on the intensity of blast in cultivar BR23 were carried out. Each temperature formed an experiment and the duration of wetness the treatments. The highest blast intensity was observed at 30°C and increased as the duration of the wetting period increased while the lowest occurred at 25°C and 10 hours of spike wetness. Regardless of the temperature, no symptoms occurred when the wetting period was less than 10 hours but at 25°C and a 40 h wetting period blast intensity exceeded 85%. These variations in blast intensity as a function of temperature are explained by a generalized beta model and as a function of the duration of spike wetness by the Gompertz model. Disease intensity was modeled as a function of both temperature and the durations of spike wetness and the resulting equation provided a precise description of the response of P. grisea to temperatures and the durations of spike wetness. This model was used to construct tables that can be used to predict the intensity of P. grisea wheat blast based on the temperatures and the durations of wheat spike wetness obtained in the field.Em experimentos conduzidos em câmaras de crescimento, com o cultivar suscetível de trigo BR 23 (Triticum aestivum L. foram avaliadas as interações entre temperaturas e durações do período de molhamento contínuo das espigas sobre a intensidade da brusone (Pyricularia grisea. As temperaturas testadas foram de 10, 15, 20, 25, 30 e 35 ºC e os períodos de duração do molhamento das espigas de 0, 5, 10, 15, 20, 25, 30, 35 e 40 horas. Cada

  8. EUMYCETOMA BY Madurella grisea: REPORT OF THE FIRST CASE OBSERVED IN THE SOUTHERN BRAZILIAN REGION Eumicetoma por Madurella grisea: Relato do primeiro caso observado na Região Sul do Brasil

    Directory of Open Access Journals (Sweden)

    Luiz Carlos SEVERO

    1999-03-01

    Full Text Available The first case of eumycetoma by Madurella grisea occurred in Southern Brazilian Region is herein related. In addition, Brazilian literature on this subject was reviewed and, the geographic distribution of this eumycetoma is presented.É relatado o primeiro caso de eumicetoma por Madurella grisea ocorrido na Região Sul (Brasil. Além disso, a literatura brasileira correspondente foi revisada e a distribuição geográfica deste tipo de eumicetoma é apresentada.

  9. HUBUNAGN KEMAMPUAN PERGANTIAN INANG DENGAN PLASTISITAS GENETIKA PADA CENDAWAN BLAS PADI (PYRICULARIA GRISEA

    Directory of Open Access Journals (Sweden)

    Sri Listiyowati

    2009-08-01

    Full Text Available The Digitaria ciliaris, wild grass grown around rice field, was a host for Pyricularia grisea (Cooke Sacc., the fungi caused blast disease of rice. This fungi have a specific mechanism to regenerate new genetic variation in its life cycle. The aim of this research is to study the relation between the ability of the fungi to infect different species of host with its genetic plasticity. It was used three SCAR molecular markers Cut1, Pwl 1 and Erg2. P. grisea isolates (Dc4J1 originated from D. ciliaris at Jasinga-Bogor were able to infect rice cultivars Kencana Bali and Cisokan. The original Dc4J1, from D. ciliaris, and the Dc4J1 that were reisolated from the infected rice cultivars (reisolates-1 had the same ability to infect Kencana Bali and Cisokan. Molecular technique showed that there was a different molecular marker genotype between the original Dc4J1, from D. ciliaris, and the Dc4J1 reisolated from infected rice cultivars. The original Dc4J1 owned Cut1 but did not Pwl2 in contrary the reisolates Dc4J1 from rice cultivars (reisolates-1 had Pwl2 but did not Cut1. The Erg2 presented in both the original and the reisolated Dc4J1. These results indicated that there were a change of genotype of P. grisea at the same time with the change of host species. The Dc4J1 isolates originated from Kencana Bali and Cisokan (reisolates-2 that were infected by reisolate-1, had the same genotype with the reisolates-1

  10. Magnaporthe oryzae Glycine-Rich Secretion Protein, Rbf1 Critically Participates in Pathogenicity through the Focal Formation of the Biotrophic Interfacial Complex

    Science.gov (United States)

    Ishii-Minami, Naoko; Kawahara, Yoshihiro; Yoshida, Yuri; Okada, Kazunori; Ando, Sugihiro; Matsumura, Hideo; Terauchi, Ryohei; Minami, Eiichi; Nishizawa, Yoko

    2016-01-01

    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. PMID:27711180

  11. Identification and analysis of in planta expressed genes of Magnaporthe oryzae

    Directory of Open Access Journals (Sweden)

    Mitchell Thomas K

    2010-02-01

    Full Text Available Abstract Background Infection of plants by pathogens and the subsequent disease development involves substantial changes in the biochemistry and physiology of both partners. Analysis of genes that are expressed during these interactions represents a powerful strategy to obtain insights into the molecular events underlying these changes. We have employed expressed sequence tag (EST analysis to identify rice genes involved in defense responses against infection by the blast fungus Magnaporthe oryzae and fungal genes involved in infectious growth within the host during a compatible interaction. Results A cDNA library was constructed with RNA from rice leaves (Oryza sativa cv. Hwacheong infected with M. oryzae strain KJ201. To enrich for fungal genes, subtraction library using PCR-based suppression subtractive hybridization was constructed with RNA from infected rice leaves as a tester and that from uninfected rice leaves as the driver. A total of 4,148 clones from two libraries were sequenced to generate 2,302 non-redundant ESTs. Of these, 712 and 1,562 ESTs could be identified to encode fungal and rice genes, respectively. To predict gene function, Gene Ontology (GO analysis was applied, with 31% and 32% of rice and fungal ESTs being assigned to GO terms, respectively. One hundred uniESTs were found to be specific to fungal infection EST. More than 80 full-length fungal cDNA sequences were used to validate ab initio annotated gene model of M. oryzae genome sequence. Conclusion This study shows the power of ESTs to refine genome annotation and functional characterization. Results of this work have advanced our understanding of the molecular mechanisms underpinning fungal-plant interactions and formed the basis for new hypothesis.

  12. Resistance spectra of six elite breeding lines of upland rice to Pyricularia grisea

    Directory of Open Access Journals (Sweden)

    Prabhu Anne Sitarama

    2003-01-01

    Full Text Available The objective of this work was to evaluate the resistance spectra of six elite breeding lines of rice, developed for improved yield and grain quality, in inoculation tests in the greenhouse and in the field. Forty-six isolates of Pyricularia grisea collected from the cultivar Primavera, 31 from the cultivar Maravilha and 19 from six elite breeding lines, totaling 96 were utilized for inoculations. Out of 11 international and 15 Brazilian pathotypes, IC-1, IB-9, and BD-16, respectively, were identified as most frequent isolates collected from the cultivar Primavera. The isolates retrieved from Maravilha belong to four international and 11 Brazilian pathotypes, the predominant ones being IB-9 and IB-49 and BB-1 and BB-21, respectively. Lines CNAs 8711 and CNAs 8983 showed resistant reaction to all test isolates from Maravilha, while CNAs 8983 was susceptible to three isolates of Primavera pertaining to the pathotype IC-1. A majority of isolates exhibiting compatible reaction to Primavera were incompatible to Maravilha and vice-versa.Field assessment of rice blast utilizing the area under disease progress curve as a criterion for measuring disease severity showed significant differences among the six breeding lines. The isolates of P. grisea exhibiting differential reaction on breeding lines can be utilized in pyramiding resistance genes in new upland rice cultivars.

  13. Fungal virulence and development is regulated by alternative pre-mRNA 3'end processing in Magnaporthe oryzae.

    Directory of Open Access Journals (Sweden)

    Marina Franceschetti

    2011-12-01

    Full Text Available RNA-binding proteins play a central role in post-transcriptional mechanisms that control gene expression. Identification of novel RNA-binding proteins in fungi is essential to unravel post-transcriptional networks and cellular processes that confer identity to the fungal kingdom. Here, we carried out the functional characterisation of the filamentous fungus-specific RNA-binding protein RBP35 required for full virulence and development in the rice blast fungus. RBP35 contains an N-terminal RNA recognition motif (RRM and six Arg-Gly-Gly tripeptide repeats. Immunoblots identified two RBP35 protein isoforms that show a steady-state nuclear localisation and bind RNA in vitro. RBP35 coimmunoprecipitates in vivo with Cleavage Factor I (CFI 25 kDa, a highly conserved protein involved in polyA site recognition and cleavage of pre-mRNAs. Several targets of RBP35 have been identified using transcriptomics including 14-3-3 pre-mRNA, an important integrator of environmental signals. In Magnaporthe oryzae, RBP35 is not essential for viability but regulates the length of 3'UTRs of transcripts with developmental and virulence-associated functions. The Δrbp35 mutant is affected in the TOR (target of rapamycin signaling pathway showing significant changes in nitrogen metabolism and protein secretion. The lack of clear RBP35 orthologues in yeast, plants and animals indicates that RBP35 is a novel auxiliary protein of the polyadenylation machinery of filamentous fungi. Our data demonstrate that RBP35 is the fungal equivalent of metazoan CFI 68 kDa and suggest the existence of 3'end processing mechanisms exclusive to the fungal kingdom.

  14. A Rice Gene Homologous to Arabidopsis AGD2-LIKE DEFENSE1 Participates in Disease Resistance Response against Infection with Magnaporthe oryzae.

    Science.gov (United States)

    Jung, Ga Young; Park, Ju Yeon; Choi, Hyo Ju; Yoo, Sung-Je; Park, Jung-Kwon; Jung, Ho Won

    2016-08-01

    ALD1 (ABERRANT GROWTH AND DEATH2 [AGD2]-LIKE DEFENSE1) is one of the key defense regulators in Arabidopsis thaliana and Nicotiana benthamiana. In these model plants, ALD1 is responsible for triggering basal defense response and systemic resistance against bacterial infection. As well ALD1 is involved in the production of pipecolic acid and an unidentified compound(s) for systemic resistance and priming syndrome, respectively. These previous studies proposed that ALD1 is a potential candidate for developing genetically modified (GM) plants that may be resistant to pathogen infection. Here we introduce a role of ALD1-LIKE gene of Oryza sativa, named as OsALD1, during plant immunity. OsALD1 mRNA was strongly transcribed in the infected leaves of rice plants by Magnaporthe oryzae, the rice blast fungus. OsALD1 proteins predominantly localized at the chloroplast in the plant cells. GM rice plants over-expressing OsALD1 were resistant to the fungal infection. The stable expression of OsALD1 also triggered strong mRNA expression of PATHOGENESIS-RELATED PROTEIN1 genes in the leaves of rice plants during infection. Taken together, we conclude that OsALD1 plays a role in disease resistance response of rice against the infection with rice blast fungus.

  15. A Rice Gene Homologous to Arabidopsis AGD2-LIKE DEFENSE1 Participates in Disease Resistance Response against Infection with Magnaporthe oryzae

    Directory of Open Access Journals (Sweden)

    Ga Young Jung

    2016-08-01

    Full Text Available ALD1 (ABERRANT GROWTH AND DEATH2 [AGD2]-LIKE DEFENSE1 is one of the key defense regulators in Arabidopsis thaliana and Nicotiana benthamiana. In these model plants, ALD1 is responsible for triggering basal defense response and systemic resistance against bacterial infection. As well ALD1 is involved in the production of pipecolic acid and an unidentified compound(s for systemic resistance and priming syndrome, respectively. These previous studies proposed that ALD1 is a potential candidate for developing genetically modified (GM plants that may be resistant to pathogen infection. Here we introduce a role of ALD1-LIKE gene of Oryza sativa, named as OsALD1, during plant immunity. OsALD1 mRNA was strongly transcribed in the infected leaves of rice plants by Magnaporthe oryzae, the rice blast fungus. OsALD1 proteins predominantly localized at the chloroplast in the plant cells. GM rice plants over-expressing OsALD1 were resistant to the fungal infection. The stable expression of OsALD1 also triggered strong mRNA expression of PATHOGENESIS-RELATED PROTEIN1 genes in the leaves of rice plants during infection. Taken together, we conclude that OsALD1 plays a role in disease resistance response of rice against the infection with rice blast fungus.

  16. Danos em trigo causados pela infecção de Pyricularia grisea Damages in wheat caused by infection of Pyricularia grisea

    Directory of Open Access Journals (Sweden)

    Augusto César Pereira Goulart

    2007-12-01

    Full Text Available Este trabalho teve por objetivo quantificar os danos no rendimento de grãos, causados pela infecção natural da brusone (Pyricularia grisea, em diferentes cultivares e linhagens de trigo, na safra agrícola de 2004, no Município de Dourados, Mato Grosso do Sul, isoladamente da ocorrência de outras doenças. Trabalhou-se em condições naturais e sem o emprego de fungicidas, em parcelas experimentais, na Embrapa Agropecuária Oeste e em Indápolis. Após o espigamento, todas as espigas de trigo com sintomas típicos da brusone (ponto preto de infecção na ráquis foram identificadas e marcadas, em uma área de 1m². As espigas doentes e sadias foram colhidas, contadas e trilhadas separadamente. Os danos foram calculados com base na diferença entre o rendimento real e a estimativa do rendimento potencial. Os resultados mostraram que os danos e a incidência da brusone variaram de acordo com as cultivares/linhagens testadas e a região tritícola avaliada. As menores incidências da brusone foram observadas na cv. BR 18-Terena, com 27% e 42% de espigas infectadas, nos ensaios instalados na Embrapa Agropecuária Oeste e em Indápolis, respectivamente. O dano médio devido à brusone, registrado nos 20 materiais testados, foi de 387kg/ha, o que representou 10,5% do rendimento de grãos, no ensaio instalado na Embrapa Agropecuária Oeste. Em Indápolis, os danos foram maiores, atingindo, em média, 609kg/ha (13,0% do rendimento de grãos. As perdas em peso por espiga foram maiores (63,4% quando a infecção foi precoce em comparação à infecção tardia (46,0%. Verificou-se que houve uma compensação das perdas causadas pela doença, através do melhor desenvolvimento de grãos produzidos abaixo do ponto de estrangulamento da ráquis. Observou-se, também, que em função das espigas brancas sobressaírem-se das demais, pode-se superestimar as perdas.This work was carried out in order to quantify the damages in wheat yield due to natural

  17. White Fungus Soup

    Institute of Scientific and Technical Information of China (English)

    1994-01-01

    Ingredients: two pieces of white fungus, a handful of Chinese wolfberry fruit, dates, dried longan, lotus seeds and peanuts. Directions: 1. Soak the dried fungus in water, remove the roots and then cook. 2. Steep the Chinese wolfberry fruit, dates, dried longan, lotus seeds and peanuts in water for a while.

  18. Rice RING protein OSBBI1 with E3 ligase activity confers broad-spectrum resistance against Magnaporthe oryzae by modifying the cell wall defence

    Institute of Scientific and Technical Information of China (English)

    Wei Li; Zuhua He; Sihui Zhong; Guojun Li; Qun Li; Bizeng Mao; Yiwen Deng; Huijuan Zhang; Longjun Zeng; Fengming Song

    2011-01-01

    Emerging evidence suggests that E3 ligases play critical roles in diverse biological processes, including innate immune responses in plants. However, the mechanism of the E3 ligase involvement in plant innate immunity is unclear.We report that a rice gene, OsBBI1, encoding a RING finger protein with E3 ligase activity, mediates broad-spectrum disease resistance. The expression of OSBBI1 was induced by rice blast fungus Magnaporthe oryzae, as well as chemical inducers, benzothiadiazole and salicylic acid. Biochemical analysis revealed that OsBBI1 protein possesses E3ubiquitin ligase activity in vitro. Genetic analysis revealed that the loss of OsBBI1 function in a Tos17-insertion line increased susceptibility, while the overexpression of OsBBI1 in transgenic plants conferred enhanced resistance to multiple races of M.oryzae. This indicates that OsBBI1 modulates broad-spectrum resistance against the blast fungus. The OsBBII-overexpressing plants showed higher levels of H,O, accumulation in cells and higher levels of phenolic compounds and cross-linking of proteins in cell walls at infection sites by M. Oryzae compared with wild-type(WT)plants. The cell walls were thicker in the OsBB11-overexpressing plants and thinner in the mutant plants than in the WT plants. Our results suggest that OsBBH modulates broad-spectrum resistance to blast fungus by modifying cell wall defence responses. The functional characterization of OsBBI1 provides insight into the E3 ligase-mediated innate immunity, and a practical tool for constructing broad-spectrum resistance against the most destructive disease in rice.

  19. Purification and characterization of a novel hypersensitive response-inducing elicitor from Magnaporthe oryzae that triggers defense response in rice.

    Directory of Open Access Journals (Sweden)

    Mingjia Chen

    Full Text Available BACKGROUND: Magnaporthe oryzae, the rice blast fungus, might secrete certain proteins related to plant-fungal pathogen interactions. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we report the purification, characterization, and gene cloning of a novel hypersensitive response-inducing protein elicitor (MoHrip1 secreted by M. oryzae. The protein fraction was purified and identified by de novo sequencing, and the sequence matched the genomic sequence of a putative protein from M. oryzae strain 70-15 (GenBank accession No. XP_366602.1. The elicitor-encoding gene mohrip1 was isolated; it consisted of a 429 bp cDNA, which encodes a polypeptide of 142 amino acids with a molecular weight of 14.322 kDa and a pI of 4.53. The deduced protein, MoHrip1, was expressed in E. coli. And the expression protein collected from bacterium also forms necrotic lesions in tobacco. MoHrip1 could induce the early events of the defense response, including hydrogen peroxide production, callose deposition, and alkalization of the extracellular medium, in tobacco. Moreover, MoHrip1-treated rice seedlings possessed significantly enhanced systemic resistance to M. oryzae compared to the control seedlings. The real-time PCR results indicated that the expression of some pathogenesis-related genes and genes involved in signal transduction could also be induced by MoHrip1. CONCLUSION/SIGNIFICANCE: The results demonstrate that MoHrip1 triggers defense responses in rice and could be used for controlling rice blast disease.

  20. 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.

  1. 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.

  2. Tremella with Edible Fungus

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    (Meiwei Shuang’er)Remove the tremella and edible fungus roots, clean and drain. Slice green peppers and carrots.Heat some oil in a wok, add tremella, edible fungus, green peppers and carrots, and clear stock, salt and sugar. Simmer for two minutes. Add MSG and pepper, remove to a plate, and serve.Features: Attractively black and white.Taste: Crisp and savory.

  3. The late endosomal HOPS complex anchors active G-protein signaling essential for pathogenesis in magnaporthe oryzae

    National Research Council Canada - National Science Library

    Ramanujam, Ravikrishna; Calvert, Meredith E; Selvaraj, Poonguzhali; Naqvi, Naweed I

    2013-01-01

    In Magnaporthe oryzae, the causal ascomycete of the devastating rice blast disease, the conidial germ tube tip must sense and respond to a wide array of requisite cues from the host in order to switch...

  4. NCBI nr-aa BLAST: CBRC-OPRI-01-0711 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OPRI-01-0711 ref|XP_001522448.1| hypothetical protein MGCH7_ch7g555 [Magnaporth...e grisea 70-15] gb|EAQ71148.1| hypothetical protein MGCH7_ch7g555 [Magnaporthe grisea 70-15] XP_001522448.1 2e-07 26% ...

  5. NCBI nr-aa BLAST: CBRC-AGAM-02-0168 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-AGAM-02-0168 ref|XP_001523004.1| hypothetical protein MGCH7_ch7g1090 [Magnaporth...e grisea 70-15] gb|EAQ71683.1| hypothetical protein MGCH7_ch7g1090 [Magnaporthe grisea 70-15] XP_001523004.1 0.59 29% ...

  6. NCBI nr-aa BLAST: CBRC-TGUT-37-0248 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TGUT-37-0248 ref|XP_001521946.1| hypothetical protein MGCH7_ch7g64 [Magnaporth...e grisea 70-15] gb|EAQ70657.1| hypothetical protein MGCH7_ch7g64 [Magnaporthe grisea 70-15] XP_001521946.1 2.1 45% ...

  7. NCBI nr-aa BLAST: CBRC-TGUT-12-0017 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TGUT-12-0017 ref|XP_001522370.1| hypothetical protein MGCH7_ch7g477 [Magnaporth...e grisea 70-15] gb|EAQ71070.1| hypothetical protein MGCH7_ch7g477 [Magnaporthe grisea 70-15] XP_001522370.1 0.006 28% ...

  8. NCBI nr-aa BLAST: CBRC-DYAK-08-0031 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DYAK-08-0031 ref|XP_001522971.1| hypothetical protein MGCH7_ch7g1057 [Magnaporth...e grisea 70-15] gb|EAQ71650.1| hypothetical protein MGCH7_ch7g1057 [Magnaporthe grisea 70-15] XP_001522971.1 1.0 27% ...

  9. NCBI nr-aa BLAST: CBRC-DYAK-03-0073 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DYAK-03-0073 ref|XP_001522084.1| hypothetical protein MGCH7_ch7g201 [Magnaporth...e grisea 70-15] gb|EAQ70794.1| hypothetical protein MGCH7_ch7g201 [Magnaporthe grisea 70-15] XP_001522084.1 1.0 28% ...

  10. NCBI nr-aa BLAST: CBRC-ETEL-01-1255 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-ETEL-01-1255 ref|XP_001522178.1| hypothetical protein MGCH7_ch7g286 [Magnaporth...e grisea 70-15] gb|EAQ70879.1| hypothetical protein MGCH7_ch7g286 [Magnaporthe grisea 70-15] XP_001522178.1 1.8 33% ...

  11. Novel Taxa Associated with Human Fungal Black-Grain Mycetomas: Emarellia grisea gen. nov., sp. nov., and Emarellia paragrisea sp. nov.

    Science.gov (United States)

    Desnos-Ollivier, Marie; Campbell, Colin K.; Bridge, Paul D.; Dannaoui, Eric; Johnson, Elizabeth M.

    2016-01-01

    Eumycetoma is a debilitating, chronic, fungal infection that is endemic in India, Indonesia, and parts of Africa and South and Central America. It remains a neglected tropical disease in need of international recognition. Infections follow traumatic implantation of saprophytic fungi and frequently require radical surgery or amputation in the absence of appropriate treatment. Several fungal species can cause black-grain mycetomas, including Madurella spp. (Sordariales), Falciformispora spp., Trematosphaeria grisea, Biatriospora mackinnonii, Pseudochaetosphaeronema larense, and Medicopsis romeroi (all Pleosporales). We performed phylogenetic analyses based on five loci on 31 isolates from two international culture collections to establish the taxonomic affiliations of fungi that had been isolated from cases of black-grain mycetoma and historically classified as Madurella grisea. Although most strains were well resolved to species level and corresponded to known agents of eumycetoma, six independent isolates, which failed to produce conidia under any conditions tested, were only distantly related to existing members of the Pleosporales. Five of the six isolates shared >99% identity with each other and are described as Emarellia grisea gen. nov. and sp. nov; the sixth isolate represents a sister species in this novel genus and is described as Emarellia paragrisea. Several E. grisea isolates were present in both United Kingdom and French culture collections and had been isolated independently over 6 decades from cases of imported eumycetoma. Four of the six isolates involved patients that had originated on the Indian subcontinent. All isolates were all susceptible in vitro to the azole antifungals, but had elevated MICs with caspofungin. PMID:27076666

  12. 稻瘟病抗性鉴定田土壤宏基因组文库构建及分析%Construction and diversity analysis of metagenomic library from antagonistic Magnaporthe grisea soil

    Institute of Scientific and Technical Information of China (English)

    王闵霞; 龙虎; 蔡平钟; 高方远; 向跃武; 张志雄; 张志勇; 任光俊

    2007-01-01

    从稻瘟病抗性鉴定田中提取土壤微生物宏基因组DNA,EcoRⅠ和BamHⅠ双酶切后插入到经同样双酶切的pSK+载体中,转化至DH5α感受态细胞,构建了土壤微生物宏基因组文库.随机挑选了9个克隆测序,并通过NCBI的Blastx分析了序列可能所属的物种和基因.结果其中有6个能与库中序列达到较大匹配,3个的分析结果表明可能是新基因,说明所建文库的生物多样性和新基因数较丰富.

  13. Host-Induced Gene Silencing of Rice Blast Fungus Magnaporthe oryzae Pathogenicity Genes Mediated by the Brome Mosaic Virus.

    Science.gov (United States)

    Zhu, Lin; Zhu, Jian; Liu, Zhixue; Wang, Zhengyi; Zhou, Cheng; Wang, Hong

    2017-09-26

    Magnaportheoryzae is a devastating plant pathogen, which has a detrimental impact on rice production worldwide. Despite its agronomical importance, some newly-emerging pathotypes often overcome race-specific disease resistance rapidly. It is thus desirable to develop a novel strategy for the long-lasting resistance of rice plants to ever-changing fungal pathogens. Brome mosaic virus (BMV)-induced RNA interference (RNAi) has emerged as a useful tool to study host-resistance genes for rice blast protection. Planta-generated silencing of targeted genes inside biotrophic pathogens can be achieved by expression of M.oryzae-derived gene fragments in the BMV-mediated gene silencing system, a technique termed host-induced gene silencing (HIGS). In this study, the effectiveness of BMV-mediated HIGS in M.oryzae was examined by targeting three predicted pathogenicity genes, MoABC1,MoMAC1 and MoPMK1. Systemic generation of fungal gene-specific small interfering RNA (siRNA) molecules induced by inoculation of BMV viral vectors inhibited disease development and reduced the transcription of targeted fungal genes after subsequent M.oryzae inoculation. Combined introduction of fungal gene sequences in sense and antisense orientation mediated by the BMV silencing vectors significantly enhanced the efficiency of this host-generated trans-specific RNAi, implying that these fungal genes played crucial roles in pathogenicity. Collectively, our results indicated that BMV-HIGS system was a great strategy for protecting host plants against the invasion of pathogenic fungi.

  14. Large-Scale Gene Disruption in Magnaporthe oryzae Identifies MC69, a Secreted Protein Required for Infection by Monocot and Dicot Fungal Pathogens

    Science.gov (United States)

    Saitoh, Hiromasa; Fujisawa, Shizuko; Mitsuoka, Chikako; Ito, Akiko; Hirabuchi, Akiko; Ikeda, Kyoko; Irieda, Hiroki; Yoshino, Kae; Yoshida, Kentaro; Matsumura, Hideo; Tosa, Yukio; Win, Joe; Kamoun, Sophien; Takano, Yoshitaka; Terauchi, Ryohei

    2012-01-01

    To search for virulence effector genes of the rice blast fungus, Magnaporthe oryzae, we carried out a large-scale targeted disruption of genes for 78 putative secreted proteins that are expressed during the early stages of infection of M. oryzae. Disruption of the majority of genes did not affect growth, conidiation, or pathogenicity of M. oryzae. One exception was the gene MC69. The mc69 mutant showed a severe reduction in blast symptoms on rice and barley, indicating the importance of MC69 for pathogenicity of M. oryzae. The mc69 mutant did not exhibit changes in saprophytic growth and conidiation. Microscopic analysis of infection behavior in the mc69 mutant revealed that MC69 is dispensable for appressorium formation. However, mc69 mutant failed to develop invasive hyphae after appressorium formation in rice leaf sheath, indicating a critical role of MC69 in interaction with host plants. MC69 encodes a hypothetical 54 amino acids protein with a signal peptide. Live-cell imaging suggested that fluorescently labeled MC69 was not translocated into rice cytoplasm. Site-directed mutagenesis of two conserved cysteine residues (Cys36 and Cys46) in the mature MC69 impaired function of MC69 without affecting its secretion, suggesting the importance of the disulfide bond in MC69 pathogenicity function. Furthermore, deletion of the MC69 orthologous gene reduced pathogenicity of the cucumber anthracnose fungus Colletotrichum orbiculare on both cucumber and Nicotiana benthamiana leaves. We conclude that MC69 is a secreted pathogenicity protein commonly required for infection of two different plant pathogenic fungi, M. oryzae and C. orbiculare pathogenic on monocot and dicot plants, respectively. PMID:22589729

  15. Large-scale gene disruption in Magnaporthe oryzae identifies MC69, a secreted protein required for infection by monocot and dicot fungal pathogens.

    Directory of Open Access Journals (Sweden)

    Hiromasa Saitoh

    Full Text Available To search for virulence effector genes of the rice blast fungus, Magnaporthe oryzae, we carried out a large-scale targeted disruption of genes for 78 putative secreted proteins that are expressed during the early stages of infection of M. oryzae. Disruption of the majority of genes did not affect growth, conidiation, or pathogenicity of M. oryzae. One exception was the gene MC69. The mc69 mutant showed a severe reduction in blast symptoms on rice and barley, indicating the importance of MC69 for pathogenicity of M. oryzae. The mc69 mutant did not exhibit changes in saprophytic growth and conidiation. Microscopic analysis of infection behavior in the mc69 mutant revealed that MC69 is dispensable for appressorium formation. However, mc69 mutant failed to develop invasive hyphae after appressorium formation in rice leaf sheath, indicating a critical role of MC69 in interaction with host plants. MC69 encodes a hypothetical 54 amino acids protein with a signal peptide. Live-cell imaging suggested that fluorescently labeled MC69 was not translocated into rice cytoplasm. Site-directed mutagenesis of two conserved cysteine residues (Cys36 and Cys46 in the mature MC69 impaired function of MC69 without affecting its secretion, suggesting the importance of the disulfide bond in MC69 pathogenicity function. Furthermore, deletion of the MC69 orthologous gene reduced pathogenicity of the cucumber anthracnose fungus Colletotrichum orbiculare on both cucumber and Nicotiana benthamiana leaves. We conclude that MC69 is a secreted pathogenicity protein commonly required for infection of two different plant pathogenic fungi, M. oryzae and C. orbiculare pathogenic on monocot and dicot plants, respectively.

  16. Phenotypic virulence analysis of Pyricularia grisea isolates from Brazilian upland rice cultivars Análise fenotípica da virulência dos isolados de Pyricularia grisea, coletados em cultivares de arroz de terras altas

    Directory of Open Access Journals (Sweden)

    Marta Cristina Filippi

    2001-01-01

    Full Text Available Phenotypic virulence analysis was made on population of Pyricularia grisea isolates collected from 10 upland cultivars in three distinct rice breeding sites, with the objective of studying the degree of similarity in the phenotypic virulence among the isolates, the composition of races, and their virulence pattern. Sixteen races were identified based on the reaction type on eight standard international differentials, the predominant ones being IB9 and IB41. The virulence frequency was high on IAC47 and IAC165 among medium and early maturing cultivars, respectively. The frequency of isolates virulent was greater on upland rice cultivars (51.1% than on irrigated rice cultivars (21.8%. Both virulent and avirulent isolates were present in the population of P. grisea to the known genes in the near isogenic lines. Of72test isolates, 94.4% were virulent for genes Pi3 and Pi4a. Thevirulence frequencies were relatively lower in decreasing order on Pi1, Pi4b and Pi2. Thecoefficient of similarity ranged from 0.28 to1.0 among the isolates pertaining to different races, while within the race IB9, it varied from 0.56 to1.0. Considering the coefficient of similarity of 0.81, 72% of isolates of race IB9 exhibited similar pattern of virulence.Foi conduzido um estudo de virulência fenotípica da população de Pyricularia grisea, coletada de 10 cultivares de arroz de terras altas, em três locais distintos, objetivando determinar o grau de similaridade entre virulência fenotípica de isolados, a composição de raças fisiológicas e seu padrão de virulência nas cultivares de arroz. Identificaram-se 16 raças, com base no tipo de reação nas oito diferenciadoras internacionais, das quais IB-9 e IB-41 foram as predominantes. A freqüência de virulência foi alta nas cultivares IAC47 e IAC165 entre as de ciclo médio e precoce, respectivamente. A freqüência dos isolados virulentos nas cultivares de terras altas foi maior (51,1% do que nas cultivares

  17. Antibiotic Resistance and Fungus

    Centers for Disease Control (CDC) Podcasts

    2017-02-28

    Dr. David Denning, President of the Global Action Fund for Fungal Infections and an infectious diseases clinician, discusses antimicrobial resistance and fungus.  Created: 2/28/2017 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 2/28/2017.

  18. MoDnm1 Dynamin Mediating Peroxisomal and Mitochondrial Fission in Complex with MoFis1 and MoMdv1 Is Important for Development of Functional Appressorium in Magnaporthe oryzae.

    Directory of Open Access Journals (Sweden)

    Kaili Zhong

    2016-08-01

    Full Text Available Dynamins are large superfamily GTPase proteins that are involved in various cellular processes including budding of transport vesicles, division of organelles, cytokinesis, and pathogen resistance. Here, we characterized several dynamin-related proteins from the rice blast fungus Magnaporthe oryzae and found that MoDnm1 is required for normal functions, including vegetative growth, conidiogenesis, and full pathogenicity. In addition, we found that MoDnm1 co-localizes with peroxisomes and mitochondria, which is consistent with the conserved role of dynamin proteins. Importantly, MoDnm1-dependent peroxisomal and mitochondrial fission involves functions of mitochondrial fission protein MoFis1 and WD-40 repeat protein MoMdv1. These two proteins display similar cellular functions and subcellular localizations as MoDnm1, and are also required for full pathogenicity. Further studies showed that MoDnm1, MoFis1 and MoMdv1 are in complex to regulate not only peroxisomal and mitochondrial fission, pexophagy and mitophagy progression, but also appressorium function and host penetration. In summary, our studies provide new insights into how MoDnm1 interacts with its partner proteins to mediate peroxisomal and mitochondrial functions and how such regulatory events may link to differentiation and pathogenicity in the rice blast fungus.

  19. Inhibition Effect of Ethanol Extracts from Pueraria lobata (Willd.) Ohwi Flowers on Plant Pathogenic Fungus%野葛花乙醇提取物对植物病原真菌的抑制作用研究

    Institute of Scientific and Technical Information of China (English)

    师晓慧; 邓莉兰; 朱丽丽

    2013-01-01

    以黄瓜枯萎病菌(Fusarium oxysporum)、稻瘟病菌(Magnaporthe grisea)、柑橘青霉菌(Penicillium digitatum)、番茄灰霉病菌(Botrytis cinerea)、梨黑星病菌(Venturia nashicola)5种植物病原真菌为供试菌种,采用牛津杯法,研究了野葛花乙醇提取物的抑菌活性及其对植物病原真菌的抑菌效果.结果表明:野葛花的乙醇提取物对这5种植物病原真菌均有不同程度的抑制作用;随着提取物浓度的增大,其对植物病原真菌的抑菌效果逐渐增强,当达到某一值后,抑制效果又随其浓度的增加逐渐减弱.另外,黄瓜枯萎病菌(Fusarium oxysporum)、稻瘟病菌(Magnaporthe grisea)、柑橘青霉菌(Penicillium digitatum)、番茄灰霉病菌(Botrytis cinerea)、梨黑星病菌(Venturia nashicola)的最适野葛花乙醇提取物抑菌质量浓度分别为0.1250、0.2500、0.2500、0.2500、0.5000 g/mL,其中番茄灰霉病菌的最低抑菌质量浓度应大于0.0625g/mL.因此,野葛花的乙醇提取物在抑制植物真菌性病害方面具有广阔的开发利用前景,可作为新型植物源生物农药的良好剂型.

  20. Simultaneous RNA-seq analysis of a mixed transcriptome of rice and blast fungus interaction.

    Directory of Open Access Journals (Sweden)

    Yoshihiro Kawahara

    Full Text Available A filamentous fungus, Magnaporthe oryzae, is a causal agent of rice blast disease, which is one of the most serious diseases affecting cultivated rice, Oryza sativa. However, the molecular mechanisms underlying both rice defense and fungal attack are not yet fully understood. Extensive past studies have characterized many infection-responsive genes in the pathogen and host plant, separately. To understand the plant-pathogen interaction comprehensively, it is valuable to monitor the gene expression profiles of both interacting organisms simultaneously in the same infected plant tissue. Although the host-pathogen interaction during the initial infection stage is important for the establishment of infection, the detection of fungal gene expression in infected leaves at the stage has been difficult because very few numbers of fungal cells are present. Using the emerging RNA-Seq technique, which has a wide dynamic range for expression analyses, we analyzed the mixed transcriptome of rice and blast fungus in infected leaves at 24 hours post-inoculation, which is the point when the primary infection hyphae penetrate leaf epidermal cells. We demonstrated that our method detected the gene expression of both the host plant and pathogen simultaneously in the same infected leaf blades in natural infection conditions without any artificial treatments. The upregulation of 240 fungal transcripts encoding putative secreted proteins was observed, suggesting that these candidates of fungal effector genes may play important roles in initial infection processes. The upregulation of transcripts encoding glycosyl hydrolases, cutinases and LysM domain-containing proteins were observed in the blast fungus, whereas pathogenesis-related and phytoalexin biosynthetic genes were upregulated in rice. Furthermore, more drastic changes in expression were observed in the incompatible interactions compared with the compatible ones in both rice and blast fungus at this stage. Our

  1. Genome-Wide Comparison of Magnaporthe Species Reveals a Host-Specific Pattern of Secretory Proteins and Transposable Elements

    Science.gov (United States)

    Gowda, Malali

    2016-01-01

    Blast disease caused by the Magnaporthe species is a major factor affecting the productivity of rice, wheat and millets. This study was aimed at generating genomic information for rice and non-rice Magnaporthe isolates to understand the extent of genetic variation. We have sequenced the whole genome of the Magnaporthe isolates, infecting rice (leaf and neck), finger millet (leaf and neck), foxtail millet (leaf) and buffel grass (leaf). Rice and finger millet isolates infecting both leaf and neck tissues were sequenced, since the damage and yield loss caused due to neck blast is much higher as compared to leaf blast. The genome-wide comparison was carried out to study the variability in gene content, candidate effectors, repeat element distribution, genes involved in carbohydrate metabolism and SNPs. The analysis of repeat element footprints revealed some genes such as naringenin, 2-oxoglutarate 3-dioxygenase being targeted by Pot2 and Occan, in isolates from different host species. Some repeat insertions were host-specific while other insertions were randomly shared between isolates. The distributions of repeat elements, secretory proteins, CAZymes and SNPs showed significant variation across host-specific lineages of Magnaporthe indicating an independent genome evolution orchestrated by multiple genomic factors. PMID:27658241

  2. Alternariol 9-methyl ether from the endophytic fungus Alternaria sp. Samif01 and its bioactivities

    Directory of Open Access Journals (Sweden)

    Jingfeng Lou

    2016-03-01

    Full Text Available Abstract One bioactive compound, identified as alternariol 9-methyl ether, was isolated from the crude extract of the endophytic fungus Alternaria sp. Samif01 residing in the roots of Salvia miltiorrhiza Bunge. Alternariol 9-methyl ether was active against bacteria with minimum inhibitory concentration values ranging from 25 to 75 µg/mL and median inhibitory concentration (IC50 values ranging from 16.00 to 38.27 µg/mL. The IC50 value of alternariol 9-methyl ether against spore germination of Magnaporthe oryzae was 87.18 µg/mL. Alternariol 9-methyl ether also showed antinematodal activity against Bursaphelenchus xylophilus and Caenorhabditis elegans with IC50 values of 98.17 µg/mL and 74.62 µg/mL, respectively. This work is the first report on alternariol 9-methyl ether and its biological activities from the endophytic fungus Alternaria sp. Samif01 derived from S. miltiorrhiza Bunge. The results indicate the potential of Alternaria sp. Samif01 as a source of alternariol 9-methyl ether and also support that alternariol 9-methyl ether is a natural compound with high potential bioactivity against microorganisms.

  3. Alternariol 9-methyl ether from the endophytic fungus Alternaria sp. Samif01 and its bioactivities.

    Science.gov (United States)

    Lou, Jingfeng; Yu, Ruiting; Wang, Xiaohan; Mao, Ziling; Fu, Linyun; Liu, Yang; Zhou, Ligang

    2016-01-01

    One bioactive compound, identified as alternariol 9-methyl ether, was isolated from the crude extract of the endophytic fungus Alternaria sp. Samif01 residing in the roots of Salvia miltiorrhiza Bunge. Alternariol 9-methyl ether was active against bacteria with minimum inhibitory concentration values ranging from 25 to 75μg/mL and median inhibitory concentration (IC50) values ranging from 16.00 to 38.27μg/mL. The IC50 value of alternariol 9-methyl ether against spore germination of Magnaporthe oryzae was 87.18μg/mL. Alternariol 9-methyl ether also showed antinematodal activity against Bursaphelenchus xylophilus and Caenorhabditis elegans with IC50 values of 98.17μg/mL and 74.62μg/mL, respectively. This work is the first report on alternariol 9-methyl ether and its biological activities from the endophytic fungus Alternaria sp. Samif01 derived from S. miltiorrhiza Bunge. The results indicate the potential of Alternaria sp. Samif01 as a source of alternariol 9-methyl ether and also support that alternariol 9-methyl ether is a natural compound with high potential bioactivity against microorganisms.

  4. Indução de variabilidade na cultivar de arroz Metica-1 para resistência a Pyricularia grisea Induction of variability for resistance in the rice cultivar Metica-1 to Pyricularia grisea

    Directory of Open Access Journals (Sweden)

    Leila Garcês de Araújo

    2002-12-01

    Full Text Available A brusone é um dos fatores limitantes da produtividade da cultivar Metica-1, no Estado do Tocantins. Objetivando obter somaclones resistentes, foi realizada a indução de calos e a regeneração de plantas a partir de panículas imaturas da cultivar Metica-1. Duzentas e oitenta plantas R2 foram submetidas a inoculação inóculo de patótipos de Pyricularia grisea, ID-14 e II-1, provenientes das cultivares Metica-1 e Cica-8, respectivamente. Enquanto todas as 280 plantas R2 de Metica-1 foram resistentes em relação ao patótipo II-1, as progênies de duas plantas R1 mostraram resistência ao patótipo ID14, indicando a indução de variação genética com relação à resistência à brusone na cultivar suscetível, nas gerações iniciais. A geração R3 foi avançada e entre 280 somaclones R4 foram selecionados 51, incluindo dois somaclones, CNAI10390 e CNAI10393, que mostraram resistência vertical no viveiro de brusone. Nas gerações avançadas de R5 e R6, estes dois somaclones apresentaram resistência no viveiro e nas inoculações com cinco isolados, provenientes das cultivares Metica-1, Cica-8 e Epagri 108, e poderão ser usados como novas fontes de resistência à brusone nos programas de melhoramento de arroz.Rice blast is one of the yield limiting factors of the rice cultivar Metica-1, in the State of Tocantins, Brazil. Plants of this cultivar were regenerated from the callus cultures derived from immature panicles with the objective of obtaining blast resistant somaclones. Two hundred eighty R2 plants were assessed utilizing pathotypes ID-14 and II-1 of Pyricularia grisea, retrieved from the cultivars Metica-1 and Cica-8, respectively. While all R2 plants of the cultivar Metica1 were resistant to the pathotype II-1, the progenies of two R1 plants showed resistance to pathotype ID-14, indicating thereby the induction of genetic variation for blast resistance in the susceptible rice cultivar, in early generations. The R3

  5. NCBI nr-aa BLAST: CBRC-CPOR-01-1819 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-CPOR-01-1819 ref|XP_360004.2| hypothetical protein MGG_05379 [Magnaporthe gris...ea 70-15] gb|EDK06032.1| hypothetical protein MGG_05379 [Magnaporthe grisea 70-15] XP_360004.2 0.84 29% ...

  6. NCBI nr-aa BLAST: CBRC-DDIS-02-0182 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DDIS-02-0182 ref|XP_367191.2| hypothetical protein MGG_07116 [Magnaporthe gris...ea 70-15] gb|EDK03811.1| hypothetical protein MGG_07116 [Magnaporthe grisea 70-15] XP_367191.2 1e-35 20% ...

  7. NCBI nr-aa BLAST: CBRC-TGUT-16-0000 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TGUT-16-0000 ref|XP_360477.1| hypothetical protein MGG_10789 [Magnaporthe gris...ea 70-15] gb|EDJ94965.1| hypothetical protein MGG_10789 [Magnaporthe grisea 70-15] XP_360477.1 4e-06 43% ...

  8. NCBI nr-aa BLAST: CBRC-BTAU-01-2222 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-BTAU-01-2222 ref|XP_367042.1| hypothetical protein MGG_10672 [Magnaporthe gris...ea 70-15] gb|EDJ93900.1| hypothetical protein MGG_10672 [Magnaporthe grisea 70-15] XP_367042.1 0.14 34% ...

  9. NCBI nr-aa BLAST: CBRC-OSAT-06-0027 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OSAT-06-0027 ref|XP_369017.2| hypothetical protein MGG_00227 [Magnaporthe gris...ea 70-15] gb|EDK03184.1| hypothetical protein MGG_00227 [Magnaporthe grisea 70-15] XP_369017.2 0.003 28% ...

  10. NCBI nr-aa BLAST: CBRC-PABE-26-0230 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PABE-26-0230 ref|XP_361742.2| hypothetical protein MGG_04216 [Magnaporthe gris...ea 70-15] gb|EDJ99530.1| hypothetical protein MGG_04216 [Magnaporthe grisea 70-15] XP_361742.2 0.041 31% ...

  11. NCBI nr-aa BLAST: CBRC-DNOV-01-1771 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DNOV-01-1771 ref|XP_362881.1| hypothetical protein MGG_08556 [Magnaporthe gris...ea 70-15] gb|EDJ97065.1| hypothetical protein MGG_08556 [Magnaporthe grisea 70-15] XP_362881.1 6.9 27% ...

  12. NCBI nr-aa BLAST: CBRC-PABE-01-0119 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PABE-01-0119 ref|XP_369590.1| hypothetical protein MGG_05874 [Magnaporthe gris...ea 70-15] gb|EDJ96535.1| hypothetical protein MGG_05874 [Magnaporthe grisea 70-15] XP_369590.1 0.029 27% ...

  13. NCBI nr-aa BLAST: CBRC-OGAR-01-0029 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OGAR-01-0029 ref|XP_360222.1| hypothetical protein MGG_05596 [Magnaporthe gris...ea 70-15] gb|EDK06294.1| hypothetical protein MGG_05596 [Magnaporthe grisea 70-15] XP_360222.1 5.6 41% ...

  14. NCBI nr-aa BLAST: CBRC-ACAR-01-0225 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-ACAR-01-0225 ref|XP_370101.1| hypothetical protein MGG_06616 [Magnaporthe gris...ea 70-15] gb|EDK00426.1| hypothetical protein MGG_06616 [Magnaporthe grisea 70-15] XP_370101.1 2.1 27% ...

  15. NCBI nr-aa BLAST: CBRC-LAFR-01-1309 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-LAFR-01-1309 ref|XP_362210.1| hypothetical protein MGG_04655 [Magnaporthe gris...ea 70-15] gb|EDK05556.1| hypothetical protein MGG_04655 [Magnaporthe grisea 70-15] XP_362210.1 0.91 30% ...

  16. NCBI nr-aa BLAST: CBRC-OPRI-01-0711 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OPRI-01-0711 ref|XP_366726.1| hypothetical protein MGG_02802 [Magnaporthe gris...ea 70-15] gb|EDK01748.1| hypothetical protein MGG_02802 [Magnaporthe grisea 70-15] XP_366726.1 2e-07 26% ...

  17. NCBI nr-aa BLAST: CBRC-TBEL-01-0661 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TBEL-01-0661 ref|XP_361041.2| hypothetical protein MGG_03584 [Magnaporthe gris...ea 70-15] gb|EDJ94503.1| hypothetical protein MGG_03584 [Magnaporthe grisea 70-15] XP_361041.2 3.4 28% ...

  18. NCBI nr-aa BLAST: CBRC-LAFR-01-1289 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-LAFR-01-1289 ref|XP_363526.2| hypothetical protein MGG_01452 [Magnaporthe gris...ea 70-15] gb|EDK04841.1| hypothetical protein MGG_01452 [Magnaporthe grisea 70-15] XP_363526.2 2.5 27% ...

  19. NCBI nr-aa BLAST: CBRC-ACAR-01-0876 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-ACAR-01-0876 ref|XP_365562.2| conserved hypothetical protein [Magnaporthe gris...ea 70-15] gb|EDJ98814.1| conserved hypothetical protein [Magnaporthe grisea 70-15] XP_365562.2 8e-15 35% ...

  20. NCBI nr-aa BLAST: CBRC-ETEL-01-1552 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-ETEL-01-1552 ref|XP_360759.1| hypothetical protein MGG_03302 [Magnaporthe gris...ea 70-15] gb|EDK00184.1| hypothetical protein MGG_03302 [Magnaporthe grisea 70-15] XP_360759.1 0.14 21% ...

  1. NCBI nr-aa BLAST: CBRC-HSAP-01-0047 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-HSAP-01-0047 ref|XP_369590.1| hypothetical protein MGG_05874 [Magnaporthe gris...ea 70-15] gb|EDJ96535.1| hypothetical protein MGG_05874 [Magnaporthe grisea 70-15] XP_369590.1 0.060 24% ...

  2. NCBI nr-aa BLAST: CBRC-SARA-01-0383 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-SARA-01-0383 ref|XP_361721.2| hypothetical protein MGG_04195 [Magnaporthe gris...ea 70-15] gb|EDJ99501.1| hypothetical protein MGG_04195 [Magnaporthe grisea 70-15] XP_361721.2 1.4 24% ...

  3. NCBI nr-aa BLAST: CBRC-TNIG-15-0004 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TNIG-15-0004 ref|XP_368867.2| hypothetical protein MGG_00377 [Magnaporthe gris...ea 70-15] gb|EDK03011.1| hypothetical protein MGG_00377 [Magnaporthe grisea 70-15] XP_368867.2 1.6 30% ...

  4. NCBI nr-aa BLAST: CBRC-DSIM-06-0019 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DSIM-06-0019 ref|XP_001408122.1| hypothetical protein MGG_13607 [Magnaporthe g...risea 70-15] gb|EDJ99882.1| hypothetical protein MGG_13607 [Magnaporthe grisea 70-15] XP_001408122.1 0.41 27% ...

  5. NCBI nr-aa BLAST: CBRC-DYAK-08-0031 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DYAK-08-0031 ref|XP_366069.2| hypothetical protein MGG_10289 [Magnaporthe gris...ea 70-15] gb|EDJ94136.1| hypothetical protein MGG_10289 [Magnaporthe grisea 70-15] XP_366069.2 1.0 27% ...

  6. NCBI nr-aa BLAST: CBRC-DYAK-02-0039 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DYAK-02-0039 ref|XP_001408122.1| hypothetical protein MGG_13607 [Magnaporthe g...risea 70-15] gb|EDJ99882.1| hypothetical protein MGG_13607 [Magnaporthe grisea 70-15] XP_001408122.1 0.65 25% ...

  7. NCBI nr-aa BLAST: CBRC-PHAM-01-0935 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PHAM-01-0935 ref|XP_364470.1| hypothetical protein MGG_09456 [Magnaporthe gris...ea 70-15] gb|EDJ94837.1| hypothetical protein MGG_09456 [Magnaporthe grisea 70-15] XP_364470.1 9.1 31% ...

  8. NCBI nr-aa BLAST: CBRC-DYAK-01-0047 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DYAK-01-0047 ref|XP_369017.2| hypothetical protein MGG_00227 [Magnaporthe gris...ea 70-15] gb|EDK03184.1| hypothetical protein MGG_00227 [Magnaporthe grisea 70-15] XP_369017.2 2e-06 26% ...

  9. NCBI nr-aa BLAST: CBRC-ACAR-01-0876 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-ACAR-01-0876 ref|XP_001411588.1| hypothetical protein MGG_11671 [Magnaporthe g...risea 70-15] gb|EDK03349.1| hypothetical protein MGG_11671 [Magnaporthe grisea 70-15] XP_001411588.1 3e-14 41% ...

  10. NCBI nr-aa BLAST: CBRC-DDIS-04-0046 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DDIS-04-0046 ref|XP_369408.1| hypothetical protein MGG_06056 [Magnaporthe gris...ea 70-15] gb|EDJ96319.1| hypothetical protein MGG_06056 [Magnaporthe grisea 70-15] XP_369408.1 2e-26 28% ...

  11. NCBI nr-aa BLAST: CBRC-RNOR-06-0041 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-RNOR-06-0041 ref|XP_364130.2| hypothetical protein MGG_08975 [Magnaporthe gris...ea 70-15] gb|EDK05195.1| hypothetical protein MGG_08975 [Magnaporthe grisea 70-15] XP_364130.2 0.61 31% ...

  12. NCBI nr-aa BLAST: CBRC-DDIS-05-0055 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DDIS-05-0055 ref|XP_361085.2| hypothetical protein MGG_03628 [Magnaporthe gris...ea 70-15] gb|EDJ94444.1| hypothetical protein MGG_03628 [Magnaporthe grisea 70-15] XP_361085.2 4e-63 35% ...

  13. NCBI nr-aa BLAST: CBRC-ETEL-01-0112 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-ETEL-01-0112 ref|XP_001408122.1| hypothetical protein MGG_13607 [Magnaporthe g...risea 70-15] gb|EDJ99882.1| hypothetical protein MGG_13607 [Magnaporthe grisea 70-15] XP_001408122.1 0.004 25% ...

  14. NCBI nr-aa BLAST: CBRC-TGUT-20-0000 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TGUT-20-0000 ref|XP_364258.2| hypothetical protein MGG_09103 [Magnaporthe gris...ea 70-15] gb|EDK00931.1| hypothetical protein MGG_09103 [Magnaporthe grisea 70-15] XP_364258.2 0.009 36% ...

  15. NCBI nr-aa BLAST: CBRC-TGUT-35-0010 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TGUT-35-0010 ref|XP_366326.2| hypothetical protein MGG_10544 [Magnaporthe gris...ea 70-15] gb|EDJ94748.1| hypothetical protein MGG_10544 [Magnaporthe grisea 70-15] XP_366326.2 0.49 29% ...

  16. NCBI nr-aa BLAST: CBRC-ACAR-01-0401 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-ACAR-01-0401 ref|XP_001408122.1| hypothetical protein MGG_13607 [Magnaporthe g...risea 70-15] gb|EDJ99882.1| hypothetical protein MGG_13607 [Magnaporthe grisea 70-15] XP_001408122.1 3e-05 24% ...

  17. NCBI nr-aa BLAST: CBRC-CJAC-01-1439 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-CJAC-01-1439 ref|XP_364531.1| hypothetical protein MGG_09395 [Magnaporthe gris...ea 70-15] gb|EDJ98925.1| hypothetical protein MGG_09395 [Magnaporthe grisea 70-15] XP_364531.1 4e-09 35% ...

  18. NCBI nr-aa BLAST: CBRC-TGUT-37-0170 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TGUT-37-0170 ref|XP_001405056.1| hypothetical protein MGG_14095 [Magnaporthe g...risea 70-15] gb|EDJ96816.1| hypothetical protein MGG_14095 [Magnaporthe grisea 70-15] XP_001405056.1 2e-10 29% ...

  19. NCBI nr-aa BLAST: CBRC-AGAM-04-0104 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-AGAM-04-0104 ref|XP_001404421.1| hypothetical protein MGG_13192 [Magnaporthe g...risea 70-15] gb|EDJ96181.1| hypothetical protein MGG_13192 [Magnaporthe grisea 70-15] XP_001404421.1 0.083 31% ...

  20. NCBI nr-aa BLAST: CBRC-TGUT-37-0248 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TGUT-37-0248 ref|XP_364794.2| hypothetical protein MGG_09639 [Magnaporthe gris...ea 70-15] gb|EDK05898.1| hypothetical protein MGG_09639 [Magnaporthe grisea 70-15] XP_364794.2 2.1 45% ...

  1. NCBI nr-aa BLAST: CBRC-RNOR-02-0029 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-RNOR-02-0029 ref|XP_366265.1| hypothetical protein MGG_10484 [Magnaporthe gris...ea 70-15] gb|EDJ96746.1| hypothetical protein MGG_10484 [Magnaporthe grisea 70-15] XP_366265.1 5e-12 76% ...

  2. NCBI nr-aa BLAST: CBRC-DNOV-01-0721 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DNOV-01-0721 ref|XP_360709.2| hypothetical protein MGG_03252 [Magnaporthe gris...ea 70-15] gb|EDK00241.1| hypothetical protein MGG_03252 [Magnaporthe grisea 70-15] XP_360709.2 0.47 36% ...

  3. NCBI nr-aa BLAST: CBRC-CJAC-01-0662 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-CJAC-01-0662 ref|XP_364606.2| hypothetical protein MGG_09320 [Magnaporthe gris...ea 70-15] gb|EDJ94763.1| hypothetical protein MGG_09320 [Magnaporthe grisea 70-15] XP_364606.2 0.019 34% ...

  4. NCBI nr-aa BLAST: CBRC-EEUR-01-1333 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-EEUR-01-1333 ref|XP_359811.1| hypothetical protein MGG_04966 [Magnaporthe gris...ea 70-15] gb|EDJ95455.1| hypothetical protein MGG_04966 [Magnaporthe grisea 70-15] XP_359811.1 1.2 33% ...

  5. NCBI nr-aa BLAST: CBRC-BTAU-01-2901 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-BTAU-01-2901 ref|XP_368487.1| hypothetical protein MGG_00757 [Magnaporthe gris...ea 70-15] gb|EDK02590.1| hypothetical protein MGG_00757 [Magnaporthe grisea 70-15] XP_368487.1 3.4 22% ...

  6. NCBI nr-aa BLAST: CBRC-LAFR-01-0224 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-LAFR-01-0224 ref|XP_001408122.1| hypothetical protein MGG_13607 [Magnaporthe g...risea 70-15] gb|EDJ99882.1| hypothetical protein MGG_13607 [Magnaporthe grisea 70-15] XP_001408122.1 0.073 28% ...

  7. NCBI nr-aa BLAST: CBRC-PMAR-01-0188 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PMAR-01-0188 ref|XP_360837.2| hypothetical protein MGG_03380 [Magnaporthe gris...ea 70-15] gb|EDK00095.1| hypothetical protein MGG_03380 [Magnaporthe grisea 70-15] XP_360837.2 0.084 25% ...

  8. NCBI nr-aa BLAST: CBRC-ACAR-01-1198 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-ACAR-01-1198 ref|XP_360819.1| hypothetical protein MGG_03362 [Magnaporthe gris...ea 70-15] gb|EDK00116.1| hypothetical protein MGG_03362 [Magnaporthe grisea 70-15] XP_360819.1 6.8 27% ...

  9. NCBI nr-aa BLAST: CBRC-DNOV-01-2937 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DNOV-01-2937 ref|XP_360709.2| hypothetical protein MGG_03252 [Magnaporthe gris...ea 70-15] gb|EDK00241.1| hypothetical protein MGG_03252 [Magnaporthe grisea 70-15] XP_360709.2 0.46 36% ...

  10. NCBI nr-aa BLAST: CBRC-CFAM-34-0004 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-CFAM-34-0004 ref|XP_001414935.1| hypothetical protein MGG_14465 [Magnaporthe g...risea 70-15] gb|EDK06709.1| predicted protein [Magnaporthe grisea 70-15] XP_001414935.1 0.066 37% ...

  11. NCBI nr-aa BLAST: CBRC-PTRO-10-0019 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-PTRO-10-0019 ref|XP_367068.2| hypothetical protein MGG_10698 [Magnaporthe gris...ea 70-15] gb|EDJ94112.1| hypothetical protein MGG_10698 [Magnaporthe grisea 70-15] XP_367068.2 2.8 30% ...

  12. NCBI nr-aa BLAST: CBRC-MMUR-01-1572 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MMUR-01-1572 ref|XP_364376.1| hypothetical protein MGG_09221 [Magnaporthe gris...ea 70-15] gb|EDJ97982.1| hypothetical protein MGG_09221 [Magnaporthe grisea 70-15] XP_364376.1 3.5 26% ...

  13. Cyanide, a Coproduct of Plant Hormone Ethylene Biosynthesis, Contributes to the Resistance of Rice to Blast Fungus1[W][OA

    Science.gov (United States)

    Seo, Shigemi; Mitsuhara, Ichiro; Feng, Jiao; Iwai, Takayoshi; Hasegawa, Morifumi; Ohashi, Yuko

    2011-01-01

    Rice (Oryza sativa) plants carrying the Pi-i resistance gene to blast fungus Magnaporthe oryzae restrict invaded fungus in infected tissue via hypersensitive reaction or response (HR), which is accompanied by rapid ethylene production and formation of small HR lesions. Ethylene biosynthesis has been implicated to be important for blast resistance; however, the individual roles of ethylene and cyanide, which are produced from the precursor 1-aminocyclopropane-1-carboxylic acid, remain unevaluated. In this study, we found that Pi-i-mediated resistance was compromised in transgenic rice lines, in which ethylene biosynthetic enzyme genes were silenced and then ethylene production was inhibited. The compromised resistance in transgenic lines was recovered by exogenously applying cyanide but not ethephon, an ethylene-releasing chemical in plant tissue. In a susceptible rice cultivar, treatment with cyanide or 1-aminocyclopropane-1-carboxylic acid induced the resistance to blast fungus in a dose-dependent manner, while ethephon did not have the effect. Cyanide inhibited the growth of blast fungus in vitro and in planta, and application of flavonoids, secondary metabolites that exist ubiquitously in the plant kingdom, enhanced the cyanide-induced inhibition of fungal growth. These results suggested that cyanide, whose production is triggered by HR in infected tissue, contributes to the resistance in rice plants via restriction of fungal growth. PMID:21075959

  14. Perspectivas del uso de bacterias rizosféricas en el control de pyricularia grisea (cooke sacc.) en el cultivo del arroz (oryza sativa l.)

    OpenAIRE

    Acebo Guerrero, Yanelis; Hernández-Rodríguez, Annia; Rives Rodríguez, Narovis; Hernández-Lauzardo, Ana Niurka

    2011-01-01

    Prospect of the use of bacteria in the control Pyricularia grisea (Cooke Sacc.) on rice (Oriza sativa L.) Título corto: Bacterias rizosféricas para controlar la piriculariosis ResumenEl arroz es fuente de alimento para una gran parte de la población mundial, con alto promedio de consumo anual. En este cultivo las enfermedades de origen microbiano constituyen uno de los factores que inciden en la obtención de bajos rendimientos y calidad de los granos. La piriculariosis o añublo del arroz, cau...

  15. Perspectivas del uso de bacterias rizosféricas en el control de Pyricularia grisea (Cooke Sacc.) en el cultivo del arroz (Oryza sativa L.)

    OpenAIRE

    Yanelis Acebo Guerrero; Annia Hernández-Rodríguez; Narovis Rives Rodríguez; Ana Niurka Hernández-Lauzardo

    2011-01-01

    Prospect of the use of bacteria in the control Pyricularia grisea (Cooke Sacc.) on rice (Oriza sativa L.) Título corto: Bacterias rizosféricas para controlar la piriculariosis ResumenEl arroz es fuente de alimento para una gran parte de la población mundial, con alto promedio de consumo anual. En este cultivo las enfermedades de origen microbiano constituyen uno de los factores que inciden en la obtención de bajos rendimientos y calidad de los granos. La piriculariosis o añublo del arroz, cau...

  16. Perspectivas del uso de bacterias rizosféricas en el control de Pyricularia grisea (Cooke Sacc.) en el cultivo del arroz (Oryza sativa L.)

    OpenAIRE

    Yanelis Acebo Guerrero; Annia Hernández-Rodríguez; Narovis Rives Rodríguez; Miguel Gerardo Velázquez del Valle; Ana Niurka Hernández-Lauzardo

    2011-01-01

    El arroz es fuente de alimento para una gran parte de la población mundial, con alto promedio de consumo anual. En este cultivo las enfermedades de origen microbiano constituyen uno de los factores que inciden en la obtención de bajos rendimientos y calidad de los granos. La piriculariosis o añublo del arroz, causada por Pyricularia grisea, es la enfermedad más importante en este cultivo en América Latina, ya que puede provocar hasta el 100% de reducción de los rendimientos. Como parte de la ...

  17. Pyriculins A and B, two monosubstituted hex-4-ene-2,3-diols and other phytotoxic metabolites produced by Pyricularia grisea isolated from buffelgrass (Cenchrus ciliaris)

    Science.gov (United States)

    Marco Masi; Susan Meyer; Marcin Gorecki; Alessandro Mandoli; Lorenzo Di Bari; Gennaro Pescitelli; Alessio Cimmino; Massimo Cristofaro; Suzette Clement; Antonio Evidente

    2017-01-01

    Pyricularia grisea has been identified as a foliar pathogen on buffelgrass (Cenchrus ciliaris) in North America and was studied as a potential source of phytotoxins for buffelgrass control. Two monosubstituted hex‐4‐ene‐2,3‐diols, named pyriculins A and B, were isolated from its culture filtrate organic extract together with (10S,11S)‐(−)‐epipyriculol, trans‐3...

  18. MoSET1 (Histone H3K4 Methyltransferase in Magnaporthe oryzae Regulates Global Gene Expression during Infection-Related Morphogenesis.

    Directory of Open Access Journals (Sweden)

    Kieu Thi Minh Pham

    2015-07-01

    Full Text Available Here we report the genetic analyses of histone lysine methyltransferase (KMT genes in the phytopathogenic fungus Magnaporthe oryzae. Eight putative M. oryzae KMT genes were targeted for gene disruption by homologous recombination. Phenotypic assays revealed that the eight KMTs were involved in various infection processes at varying degrees. Moset1 disruptants (Δmoset1 impaired in histone H3 lysine 4 methylation (H3K4me showed the most severe defects in infection-related morphogenesis, including conidiation and appressorium formation. Consequently, Δmoset1 lost pathogenicity on wheat host plants, thus indicating that H3K4me is an important epigenetic mark for infection-related gene expression in M. oryzae. Interestingly, appressorium formation was greatly restored in the Δmoset1 mutants by exogenous addition of cAMP or of the cutin monomer, 16-hydroxypalmitic acid. The Δmoset1 mutants were still infectious on the super-susceptible barley cultivar Nigrate. These results suggested that MoSET1 plays roles in various aspects of infection, including signal perception and overcoming host-specific resistance. However, since Δmoset1 was also impaired in vegetative growth, the impact of MoSET1 on gene regulation was not infection specific. ChIP-seq analysis of H3K4 di- and tri-methylation (H3K4me2/me3 and MoSET1 protein during infection-related morphogenesis, together with RNA-seq analysis of the Δmoset1 mutant, led to the following conclusions: 1 Approximately 5% of M. oryzae genes showed significant changes in H3K4-me2 or -me3 abundance during infection-related morphogenesis. 2 In general, H3K4-me2 and -me3 abundance was positively associated with active transcription. 3 Lack of MoSET1 methyltransferase, however, resulted in up-regulation of a significant portion of the M. oryzae genes in the vegetative mycelia (1,491 genes, and during infection-related morphogenesis (1,385 genes, indicating that MoSET1 has a role in gene repression either

  19. 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

  20. PKA activity is essential for relieving the suppression of hyphal growth and appressorium formation by MoSfl1 in Magnaporthe oryzae.

    Directory of Open Access Journals (Sweden)

    Yang Li

    2017-08-01

    Full Text Available In the rice blast fungus Magnaporthe oryzae, the cAMP-PKA pathway regulates surface recognition, appressorium turgor generation, and invasive growth. However, deletion of CPKA failed to block appressorium formation and responses to exogenous cAMP. In this study, we generated and characterized the cpk2 and cpkA cpk2 mutants and spontaneous suppressors of cpkA cpk2 in M. oryzae. Our results demonstrate that CPKA and CPK2 have specific and overlapping functions, and PKA activity is essential for appressorium formation and plant infection. Unlike the single mutants, the cpkA cpk2 mutant was significantly reduced in growth and rarely produced conidia. It failed to form appressoria although the intracellular cAMP level and phosphorylation of Pmk1 MAP kinase were increased. The double mutant also was defective in plant penetration and Mps1 activation. Interestingly, it often produced fast-growing spontaneous suppressors that formed appressoria but were still non-pathogenic. Two suppressor strains of cpkA cpk2 had deletion and insertion mutations in the MoSFL1 transcription factor gene. Deletion of MoSFL1 or its C-terminal 93-aa (MoSFL1ΔCT was confirmed to suppress the defects of cpkA cpk2 in hyphal growth but not appressorium formation or pathogenesis. We also isolated 30 spontaneous suppressors of the cpkA cpk2 mutant in Fusarium graminearum and identified mutations in 29 of them in FgSFL1. Affinity purification and co-IP assays showed that this C-terminal region of MoSfl1 was essential for its interaction with the conserved Cyc8-Tup1 transcriptional co-repressor, which was reduced by cAMP treatment. Furthermore, the S211D mutation at the conserved PKA-phosphorylation site in MoSFL1 partially suppressed the defects of cpkA cpk2. Overall, our results indicate that PKA activity is essential for appressorium formation and proper activation of Pmk1 or Mps1 in M. oryzae, and phosphorylation of MoSfl1 by PKA relieves its interaction with the Cyc8-Tup1 co

  1. Phylogenomic analysis uncovers the evolutionary history of nutrition and infection mode in rice blast fungus and other Magnaporthales.

    Science.gov (United States)

    Luo, Jing; Qiu, Huan; Cai, Guohong; Wagner, Nicole E; Bhattacharya, Debashish; Zhang, Ning

    2015-03-30

    The order Magnaporthales (Ascomycota, Fungi) includes devastating pathogens of cereals, such as the rice blast fungus Pyricularia (Magnaporthe) oryzae, which is a model in host-pathogen interaction studies. Magnaporthales also includes saprotrophic species associated with grass roots and submerged wood. Despite its scientific and economic importance, the phylogenetic position of Magnaporthales within Sordariomycetes and the interrelationships of its constituent taxa, remain controversial. In this study, we generated novel transcriptome data from 21 taxa that represent key Magnaporthales lineages of different infection and nutrition modes and phenotypes. Phylogenomic analysis of >200 conserved genes allowed the reconstruction of a robust Sordariomycetes tree of life that placed the monophyletic group of Magnaporthales sister to Ophiostomatales. Among Magnaporthales, three major clades were recognized: 1) an early diverging clade A comprised of saprotrophs associated with submerged woods; 2) clade B that includes the rice blast fungus and other pathogens that cause blast diseases of monocot plants. These species infect the above-ground tissues of host plants using the penetration structure, appressorium; and 3) clade C comprised primarily of root-associated species that penetrate the root tissue with hyphopodia. The well-supported phylogenies provide a robust framework for elucidating evolution of pathogenesis, nutrition modes, and phenotypic characters in Magnaporthales.

  2. Genetic diversity and virulence pattern in field populations of Pyricularia grisea from rice cultivar Metica-1 Diversidade genética e padrão de virulência em populações de Pyricularia grisea provenientes da cultivar de arroz Metica-1

    Directory of Open Access Journals (Sweden)

    Marta Cristina Filippi

    2002-12-01

    Full Text Available Rice blast is a major yield constraint of the irrigated rice in the State of Tocantins, Brazil. The objective of this investigation was to study the phenotypic and genetic diversity within the pathogen population of Pyricularia grisea in samples collected from four individual farms of rice cultivar Metica-1, under epidemic conditions of leaf blast. A set of 87 isolates was tested on 32 rice genotypes including eight international differentials. Considering 80% similarity in virulence, two groups comprising a total of 81 isolates were recognized, independently of the farms from which they were collected. Eighty percent of the isolates pertained to pathotype ID-14, indicating high cultivar specificity and narrow diversity of virulence in the sample population. The virulence in pathogen population on rice cultivars BR-IRGA 409 and Rio Formoso was low. Analysis of P. grisea isolates using rep-PCR with two primer sequences from Pot2 generated fingerprint profiles of one to nine bands. Cluster analysis revealed the occurrence of six fingerprint groups with similarities ranging from 0.09 to 1. There was no straight relationship between virulence of the isolates based on reaction pattern on 32 genotypes and grouping based on Pot2 rep-PCR analysis of P. grisea isolates collected from 'Metica-1'.A brusone é um dos fatores limitantes para a produção de arroz de várzea no Estado do Tocantins. A diversidade fenotípica e genética em população de Pyricularia grisea foi estudada, em amostras coletadas em quatro lavouras da cultivar Metica-1, sob condições de epidemias de brusone nas folhas. Foram testados 87 isolados em 32 genótipos, incluindo oito diferenciadoras internacionais. Considerando 80% de similaridade em virulência, dois grupos compostos por 81 isolados foram identificados, independentemente das lavouras onde foram coletados. Oitenta por cento dos isolados pertencem ao patótipo ID-14, indicando alta especificidade da cultivar e a

  3. Fungal Histidine Phosphotransferase Plays a Crucial Role in Photomorphogenesis and Pathogenesis in Magnaporthe oryzae

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    Varsha C. Mohanan

    2017-05-01

    Full Text Available Two-component signal transduction (TCST pathways play crucial roles in many cellular functions such as stress responses, biofilm formation, and sporulation. The histidine phosphotransferase (HPt, which is an intermediate phosphotransfer protein in a two-component system, transfers a phosphate group to a phosphorylatable aspartate residue in the target protein(s, and up-regulates stress-activated MAP kinase cascades. Most fungal genomes carry a single copy of the gene coding for HPt, which are potential antifungal targets. However, unlike the histidine kinases (HK or the downstream response regulators (RR in two-component system, the HPts have not been well-studied in phytopathogenic fungi. In this study, we investigated the role of HPt in the model rice-blast fungal pathogen Magnaporthe oryzae. We found that in M. oryzae an additional isoform of the HPT gene YPD1 was expressed specifically in response to light. Further, the expression of light-regulated genes such as those encoding envoy and blue-light-harvesting protein, and PAS domain containing HKs was significantly reduced upon down-regulation of YPD1 in M. oryzae. Importantly, down-regulation of YPD1 led to a significant decrease in the ability to penetrate the host cuticle and in light-dependent conidiation in M. oryzae. Thus, our results indicate that Ypd1 plays an important role in asexual development and host invasion, and suggest that YPD1 isoforms likely have distinct roles to play in the rice-blast pathogen M. oryzae.

  4. Autophagy-associated alpha-arrestin signaling is required for conidiogenous cell development in Magnaporthe oryzae

    Science.gov (United States)

    Dong, Bo; Xu, Xiaojin; Chen, Guoqing; Zhang, Dandan; Tang, Mingzhi; Xu, Fei; Liu, Xiaohong; Wang, Hua; Zhou, Bo

    2016-01-01

    Conidiation patterning is evolutionarily complex and mechanism concerning conidiogenous cell differentiation remains largely unknown. Magnaporthe oryzae conidiates in a sympodial way and uses its conidia to infect host and disseminate blast disease. Arrestins are multifunctional proteins that modulate receptor down-regulation and scaffold components of intracellular trafficking routes. We here report an alpha-arrestin that regulates patterns of conidiation and contributes to pathogenicity in M. oryzae. We show that disruption of ARRDC1 generates mutants which produce conidia in an acropetal array and ARRDC1 significantly affects expression profile of CCA1, a virulence-related transcription factor required for conidiogenous cell differentiation. Although germ tubes normally develop appressoria, penetration peg formation is dramatically impaired and Δarrdc1 mutants are mostly nonpathogenic. Fluorescent analysis indicates that EGFP-ARRDC1 puncta are well colocalized with DsRed2-Atg8, and this distribution profile could not be altered in Δatg9 mutants, suggesting ARRDC1 enters into autophagic flux before autophagosome maturation. We propose that M. oryzae employs ARRDC1 to regulate specific receptors in response to conidiation-related signals for conidiogenous cell differentiation and utilize autophagosomes for desensitization of conidiogenous receptor, which transmits extracellular signal to the downstream elements of transcription factors. Our investigation extends novel significance of autophagy-associated alpha-arrestin signaling to fungal parasites. PMID:27498554

  5. Molecular Scree ning of Blast Resistance Genes in Rice Germplasms Resistant to Magnaporthe oryzae

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    Liang Yan

    2017-01-01

    Full Text Available Molecular screening of major rice blast resistance genes was determined with molecular markers, which showed close-set linkage to 11 major rice blast resistance genes (Pi-d2, Pi-z, Piz-t, Pi-9, Pi-36, Pi-37, Pi5, Pi-b, Pik-p, Pik-h and Pi-ta2, in a collection of 32 accessions resistant to Magnaporthe oryzae. Out of the 32 accessions, the Pi-d2 and Pi-z appeared to be omnipresent and gave positive express. As the second dominant, Pi-b and Piz-t gene frequencies were 96.9% and 87.5%. And Pik-h and Pik-p gene frequencies were 43.8% and 28.1%, respectively. The molecular marker linkage to Pi-ta2 produced positive bands in eleven accessions, while the molecular marker linkage to Pi-36 and Pi-37 in only three and four accessions, respectively. The natural field evaluation analysis showed that 30 of the 32 accessions were resistant, one was moderately resistant and one was susceptible. Infection types were negatively correlated with the genotype scores of Pi-9, Pi5, Pi-b, Pi-ta2 and Pik-p, although the correlation coefficients were very little. These results are useful in identification and incorporation of functional resistance genes from these germplasms into elite cultivars through marker-assisted selection for improved blast resistance in China and worldwide.

  6. 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.

  7. Fungal histidine phosphotransferase plays a crucial role in photomorphogenesis and pathogenesis in Magnaporthe oryzae

    Science.gov (United States)

    Mohanan, Varsha C.; Chandarana, Pinal M.; Chattoo, Bharat. B.; Patkar, Rajesh N.; Manjrekar, Johannes

    2017-05-01

    Two-component signal transduction (TCST) pathways play crucial roles in many cellular functions such as stress responses, biofilm formation and sporulation. The histidine phosphotransferase (HPt), which is an intermediate phosphotransfer protein in a two-component system, transfers a phosphate group to a phosphorylatable aspartate residue in the target protein(s), and up-regulates stress-activated MAP kinase cascades. Most fungal genomes carry a single copy of the gene coding for HPt, which are potential antifungal targets. However, unlike the histidine kinases (HK) or the downstream response regulators (RR) in two-component system, the HPts have not been well studied in phytopathogenic fungi. In this study, we investigated the role of HPt in the model rice-blast fungal pathogen Magnaporthe oryzae. We found that in M. oryzae an additional isoform of the HPT gene YPD1 was expressed specifically in response to light. Further, the expression of light-regulated genes such as those encoding envoy and blue-light-harvesting protein, and PAS domain containing HKs was significantly reduced upon down-regulation of YPD1 in M. oryzae. Importantly, down-regulation of YPD1 led to a significant decrease in the ability to penetrate the host cuticle and in light-dependent conidiation in M. oryzae. Thus, our results indicate that Ypd1 plays an important role in asexual development and host invasion, and suggest that YPD1 isoforms likely have distinct roles to play in the rice-blast pathogen M. oryzae.

  8. Retromer Is Essential for Autophagy-Dependent Plant Infection by the Rice Blast Fungus

    Science.gov (United States)

    He, Yunlong; Xie, Qiurong; Chen, Ahai; Zheng, Huawei; Shi, Lei; Zhao, Xu; Zhang, Chengkang; Huang, Qingping; Fang, Kunhai; Lu, Guodong; Ebbole, Daniel J.; Li, Guangpu; Naqvi, Naweed I.; Wang, Zonghua

    2015-01-01

    The retromer mediates protein trafficking through recycling cargo from endosomes to the trans-Golgi network in eukaryotes. However, the role of such trafficking events during pathogen-host interaction remains unclear. Here, we report that the cargo-recognition complex (MoVps35, MoVps26 and MoVps29) of the retromer is essential for appressorium-mediated host penetration by Magnaporthe oryzae, the causal pathogen of the blast disease in rice. Loss of retromer function blocked glycogen distribution and turnover of lipid bodies, delayed nuclear degeneration and reduced turgor during appressorial development. Cytological observation revealed dynamic MoVps35-GFP foci co-localized with autophagy-related protein RFP-MoAtg8 at the periphery of autolysosomes. Furthermore, RFP-MoAtg8 interacted with MoVps35-GFP in vivo, RFP-MoAtg8 was mislocalized to the vacuole and failed to recycle from the autolysosome in the absence of the retromer function, leading to impaired biogenesis of autophagosomes. We therefore conclude that retromer is essential for autophagy-dependent plant infection by the rice blast fungus. PMID:26658729

  9. Evaluación agronómica de líneas mutantes de arroz con tolerancia a Pyricularia grisea (ING

    Directory of Open Access Journals (Sweden)

    Jorge Madriz Muñoz

    2016-03-01

    Full Text Available Utilizando el procedimiento de mutagénesis inducida con rayos Gamma Co60, seguida de selección individual, CRUZ et al. (1992 lograron obtener 53 plantas de arroz con resistencia parcial a Pyricularia grisea (Cooke Sacc. provenientes de una variedad comercial (CR-1113 originalmente susceptible a esta enfermedad. La primera etapa del presente trabajo consistió en la evaluación de 52 líneas obtenidas por los autores mencionados. De ellas se seleccionaron 14, siete por su buen comportamiento agronómico, buen rendimiento y resistencia parcial a la enfermedad, y siete por su precocidad y buenas características agronómicas. Posteriormente estas líneas fueron reproducidas y evaluadas en ensayos de campo. Los resultados obtenidos confirmaron que las líneas escogidas mantenían las características ventajosas por las que fueron seleccionadas.

  10. 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

  11. Genomic organization and sequence dynamics of the AvrPiz-t locus in Magnaporthe oryzae

    Institute of Scientific and Technical Information of China (English)

    Ping LI; Bin BAI; Hong-yan ZHANG; Heng ZHOU; Bo ZHOU

    2012-01-01

    Plants utilize multiple layers of defense mechanisms to fight against the invasion of diverse pathogens.The R gene mediates resistance,in most cases,dependent on the co-existence of its cognate pathogen-derived avirulence (Avr) gene.The rice blast R gene Piz-t corresponds in gene-for-gene fashion to the Magnaporthe oryzae Avrgene AvrPiz-t.In this study,we determined and compared the genomic sequences surrounding the AvrPiz-t gene in both avirulent and virulent isolates,designating as AvrPiz-t-ZB15 and avrPiz-t-70-15 regions,respectively.The sequence of the AvrPiz-t-ZB15 region is 120966 bp whereas avrPiz-t-70-15 is 146292 bp in length.The extreme sequence similarity and good synteny in gene order and content along with the absence of two predicted genes in the avrPiz-t-70-15 region were observed in the predicted protein-coding regions in the AvrPiz-t locus.Nevertheless,frequent presence/absence and highly dynamic organization of transposable elements (TEs) were identified,representing the major variation of the AvrPiz-t locus between different isolates.Moreover,TEs constitute 27.3% and 43.2%of the genomic contents of the AvrPiz-t-ZB15 and avrPiz-t-70-15 regions,respectively,indicating that TEs contribute largely to the organization and evolution of AvrPiz-t locus.The findings of this study suggest that M.oryzae could benefit in an evolutionary sense from the presence of active TEs in genes conferring avirulence and provide an ability to rapidly change and thus to overcome host R genes.

  12. Development of a quantitative loop-mediated isothermal amplification (qLAMP) assay for the detection of Magnaporthe oryzae airborne inoculum in turf ecosystems

    Science.gov (United States)

    Grey Leaf Spot (GLS) is a detrimental disease of perennial ryegrass caused by a host-specialized form of Magnaporthe oryzae (Mot). In order to improve turf management, a quantitative loop-mediated isothermal amplification (LAMP) assay coupled with a simple spore trap is being developed to monitor GL...

  13. Obtaining transgenic rice resistant to rice fungal blast disease by controlled cell death strategy

    Institute of Scientific and Technical Information of China (English)

    MAO Shengji; GU Hongya; QU Lijia; CHEN Zhangliang

    2003-01-01

    The strategy of the two-component system, composed of Barnase and Barstar which encode RNase and a specific inhibitor to the RNase respectively, is adopted to obtain transgenic rice resistant to rice fungal blast disease. In this study, two chimeric promoters, induced by rice blast fungus pathogen (Magnaporthe grisea), are fused with Barnase respectively to construct two plant expression vectors, pWBNBS and pPBNBS together with the Barstar driven by CaMV 35S promoter. The resistance of the transgenic rice lines to rice blast fungus disease and rice blight disease are evaluated. The results show that (1) the expression of Barnase is induced in rice leaves when inoculated with the spores of Magnaporthe grisea; (2) the induced expression level of Barnase surpasses the level of Barstar, which elicits a similar hypersensitive response (HR) in the leaves, and the transgenic plant shows high resistance to the rice fungal blast disease; and (3) transgenic rice plants also show obvious resistance to rice bacterial blight disease. Taken together, these results suggest that the transgenic rice plants harboring this two-component system acquire relatively broad spectrum resistance against pathogens, especially high resistance to rice fungal pathogen.

  14. Highly acidic glycans from sea cucumbers. Isolation and fractionation of fucose-rich sulfated polysaccharides from the body wall of Ludwigothurea grisea.

    Science.gov (United States)

    Mourão, P A; Bastos, I G

    1987-08-03

    The body wall of the sea cucumber contains high amounts of sulfated glycans, which differ in structure from glycosaminoglycans of animal tissues and also from the fucose-rich sulfated polysaccharides isolated from marine algae and from the jelly coat of sea urchin eggs. In Ludwigothurea grisea, glycans can be separated into three fractions which differ in molecular mass and chemical composition. The fraction containing a high-molecular-mass component has a high proportion of fucose and small amounts of amino sugars, whereas another fraction contains primarily a sulfated fucan. The third fraction, which represents the major portion of the sea cucumber polysaccharides, contains besides fucose, approximately equimolar proportions of glucuronic acid and amino sugars, and has a sulfate content higher than that in the other two fractions. Both D and L-isomers of fucose are found in these polysaccharides, and the sulfate is linked to the O-3 position of the fucose residues. The attachment position of the sulfate groups to the glucuronic acid units and amino sugars is still undetermined. It is possible that these compounds are involved in maintaining the integrity of the sea cucumber's body wall, in analogy with the role of other macromolecules in the vertebrate connective tissue.

  15. Data set from the phosphoproteomic analysis of Magnaporthe oryzae-responsive proteins in susceptible and resistant rice cultivars

    Directory of Open Access Journals (Sweden)

    Yunfeng Li

    2015-06-01

    Full Text Available Rice blast, caused by the fungal pathogen Magnaporthe oryzae, is the most destructive disease of rice and causes tremendous losses of rice yield worldwide. To explore the molecular mechanisms involved in the rice–M. oryzae interaction, we conducted a time-course phosphoproteomic analysis of leaf samples from resistant and susceptible rice cultivars infected with M. oryzae. This data article contains additional results and analysis of M. oryzae-regulated phosphoproteins in rice leaves [1]. We report the analysis of M. oryzae-regulated phosphoproteins at all time points, including Venn diagram analysis, close-up views, relative intensities, and functional category, and the MS spectra of representative phosphoprotein and representative phosphorylated peptides.

  16. Microsatellite primers for fungus-growing ants

    DEFF Research Database (Denmark)

    Villesen, Palle; Gertsch, P J; Boomsma, JJ

    2002-01-01

    developed primers and earlier published primers that were developed for fungus-growing ants. A total of 20 variable microsatellite loci, developed for six different species of fungus-growing ants, are now available for studying the population genetics and colony kin-structure of these ants.......We isolated five polymorphic microsatellite loci from a library of two thousand recombinant clones of two fungus-growing ant species, Cyphomyrmex longiscapus and Trachymyrmex cf. zeteki. Amplification and heterozygosity were tested in five species of higher attine ants using both the newly...

  17. Microsatellite Primers for Fungus-Growing Ants

    DEFF Research Database (Denmark)

    Villesen Fredsted, Palle; Gertsch, Pia J.; Boomsma, Jacobus Jan (Koos)

    2002-01-01

    developed primers and earlier published primers that were developed for fungus-growing ants. A total of 20 variable microsatellite loci, developed for six different species of fungus-growing ants, are now available for studying the population genetics and colony kin-structure of these ants.......We isolated five polymorphic microsatellite loci from a library of two thousand recombinant clones of two fungus-growing ant species, Cyphomyrmex longiscapus and Trachymyrmex cf. zeteki. Amplification and heterozygosity were tested in five species of higher attine ants using both the newly...

  18. Microsatellite Primers for Fungus-Growing Ants

    DEFF Research Database (Denmark)

    Villesen Fredsted, Palle; Gertsch, Pia J.; Boomsma, Jacobus Jan (Koos)

    2002-01-01

    We isolated five polymorphic microsatellite loci from a library of two thousand recombinant clones of two fungus-growing ant species, Cyphomyrmex longiscapus and Trachymyrmex cf. zeteki. Amplification and heterozygosity were tested in five species of higher attine ants using both the newly...... developed primers and earlier published primers that were developed for fungus-growing ants. A total of 20 variable microsatellite loci, developed for six different species of fungus-growing ants, are now available for studying the population genetics and colony kin-structure of these ants....

  19. Microsatellite primers for fungus-growing ants

    DEFF Research Database (Denmark)

    Villesen, Palle; Gertsch, P J; Boomsma, JJ

    2002-01-01

    We isolated five polymorphic microsatellite loci from a library of two thousand recombinant clones of two fungus-growing ant species, Cyphomyrmex longiscapus and Trachymyrmex cf. zeteki. Amplification and heterozygosity were tested in five species of higher attine ants using both the newly...... developed primers and earlier published primers that were developed for fungus-growing ants. A total of 20 variable microsatellite loci, developed for six different species of fungus-growing ants, are now available for studying the population genetics and colony kin-structure of these ants....

  20. Metabolites from marine fungus Aspergillus sp.

    Digital Repository Service at National Institute of Oceanography (India)

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

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

  1. U.S. National Fungus Collections

    Data.gov (United States)

    Department of Agriculture — The U.S. National Fungus Collections (BPI) are the “Smithsonian for fungi” and are the repository for over one million fungal specimens worldwide - the largest such...

  2. A new macrocyclic trichochecene from soil fungus

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    From fermentation broth of soil fungus 254-2 obtained from Yunnan province,a new macrocylic trichochecene was isolated.The structure was determined on the basis of spectroscopic evidences especially the 2-D NMR spectra.

  3. Entomology: A Bee Farming a Fungus.

    Science.gov (United States)

    Oldroyd, Benjamin P; Aanen, Duur K

    2015-11-16

    Farming is done not only by humans, but also by some ant, beetle and termite species. With the discovery of a stingless bee farming a fungus that provides benefits to its larvae, bees can be added to this list.

  4. A New Macrocyclic Trichochecene from Soil Fungus

    Institute of Scientific and Technical Information of China (English)

    TaoWANG; YiZHANG; 等

    2002-01-01

    From fermentation broth of soil fungus 254-2 obtained from Yunnan province, a new macrocylic trichochecene was isolated. The structure was determined on the basis of spectroscopie evidences especially the 2-D NMR spectra.

  5. Period, subculture number and culture color influence on the isolated Magnaporthe oryzae sporulation at the Tocantins State Influencia de la edad, número de repicagens y coloración de lo micelio en la esporulación del aislados de Magnaporthe oryzae, causante de lo añublo del arroz en el estado de Tocantins Influência da idade, número de repicagens e coloração dos micélios na esporulação de isolados de Magnaporthe oryzae, causador da brusone em arroz no estado do Tocantins

    Directory of Open Access Journals (Sweden)

    Ildon Rodrigues Nascimento

    2011-09-01

    Full Text Available

    O fungo Magnaporthe oryzae, causador da brusone do arroz, apresenta uma série de limitações de cultivo em condições controladas. Algumas características podem ser variáveis até para um mesmo isolado e exigem adaptações ou inovações dos pesquisadores para possibilitar o desenvolvimento de ensaios. Este trabalho teve o objetivo verificar, de isolados monospóricos de M. oryzae da raça IA-1 coletados no Projeto Rio Formoso, município de Formoso do Araguaia, a durabilidade das culturas armazenadas em laboratório, a quantidade máxima de repicagens para manter a produção satisfatória de conídios pelas colônias e a relação de diferentes colorações das culturas em meio BDA com a produção de conídios. Para tanto, realizou-se três ensaios em delineamento inteiramente casualizado. No Ensaio I, utilizaram-se culturas com 10, 14, 18, 22, 26 e 30 dias após a repicagem. No Ensaio II, utilizaram-se culturas com 0, 1, 2, 3 e 4 repicagens a partir da cultura original. No Ensaio III, classificaram-se as culturas como Negra, Centro cinza com largas bordas brancas, Cinza, Centro cinza com estreitas bordas brancas e Branca. Maiores esporulações de M. oryzae foram obtidas em culturas com 14 dias após a repicagem, na segunda repicagem e de coloração negra.

    The fungus Magnaporthe oryzae, that caused the blast rice disease, present several restrictions for cultivation under laboratory conditions. Any characters can be variable even for the same isolate and need adaptations or innovations of the researchers for experimental development. This work aimed to verify the M. oryzae monosporic isolates of the IA-1 race collected at Projeto Rio Formoso, Formoso do Araguaia Municipality, the period of the cultures stored under laboratory conditions, the maximum quantity of the subcultures to keep the production of the conidia for the colonies satisfactory and

  6. Development of a SCAR marker linked to avirulence gene AVR-Pikm in rice blast fungus Magna porthe grisea%一个与稻瘟病菌无毒基因AVR-Pikm连锁的SCAR标记的分离

    Institute of Scientific and Technical Information of China (English)

    刘俊峰; 张国珍; 马秋娟; 彭友良

    2003-01-01

    本研究将以前在稻瘟病菌菌株S1522获得的与决定对水稻品种梅雨明无毒性的基因(AVR-Pikmm)相连锁的1个RAPD标记OPO121000进行了克隆和鉴定.核苷酸序列测定与分析结果表明:OPO121000的大小为946个碱基,不含有与已报道的稻瘟病菌Mg-SINE、Fosburry、Magyy、Grasshopper、Pot2以及Pot3等同源的重复序列.根据OPO12100o的核苷酸序列,设计了1对24个核苷酸的特异引物,对无毒表型亲本S1522和毒性表型亲本S159、无毒表型群体基因池、毒性表型基因池以及有性杂交后代108个菌株进行了PCR扩增,所有无毒表型的菌株均能特异性地扩增出1条与OPO121000大小相同的DNA条带,而毒性表型的菌株除5个重组个体外,均不能扩增出这条特异带.此结果表明,与稻瘟病菌无毒基因AVR-Pikm连锁的RAPD标记OPO121000被成功地转化为SCAR标记,为进一步通过染色体步移克隆该无毒基因奠定了基础.

  7. Host Active Defense Responses Occur within 24 Hours after Pathogen Inoculation in the Rice Blast System

    Institute of Scientific and Technical Information of China (English)

    WANG Zhong-hua; JIA Yu-lin; LIN Hui; Adair INTERN; Barbara VALENT; J. Neil RUTGER

    2007-01-01

    Phenotypical, cytological and molecular responses of rice to the fungus Magnaporthe grisea were studied using rice cultivars and lesion mimic plants. The cultivar Katy was susceptible to several virulent M. grisea isolates, and a Sekiguchi like-lesion mimic mutant of Katy (LmmKaty) showed enhanced resistance to these isolates. Lesion mimic phenotype of LmmKaty was rapidly induced by virulent M. grisea isolates or by avirulent ones only at high levels of inoculum.Autofluorescence (a sign of an active defense response) was visible under ultraviolet light 24 h after localized inoculation in the incompatible interaction, whereas, not evident in the compatible interaction. Autofluorescence was also observed in LmmKaty 20 h after pathogen inoculation, indicating that rapid cell death is a mechanism of LmmKaty to restrict pathogen invasion. Rapid accumulations of defense related (DR) gene transcripts, phenylalanine ammonia lyase and β-glucanase,were observed beginning at 6 h and were obvious at 16 h and 24 h after inoculation in an incompatible interaction. Rapid transcript accumulations of PR-1 and chitinase had occurred by 24 h after inoculation in an incompatible interaction.Accumulations of these transcripts were delayed in the compatible interaction. These results indicate that host active defense responses occur 24 h after pathogen inoculation and that LmmKaty exhibits enhanced resistance to M. grisea. It is suggested that the autofluorescence and expression of the DR genes after heavy inoculation are important cytological and molecular markers respectively for early determination of the host response to M. grisea in the rice blast system.

  8. OsSERK1 regulates rice development but not immunity to Xanthomonas oryzae pv. oryzae or Magnaporthe oryzae

    Institute of Scientific and Technical Information of China (English)

    Shimin Zuo; and Pamela C Ronald; Xiaogang Zhou; Mawsheng Chen; Shilu Zhang; Benjamin Schwessinger; Deling Ruan; Can Yuan; Jing Wang; Xuewei Chen

    2014-01-01

    Somatic embryogenesis receptor kinase (SERK) proteins play pivotal roles in regulation of plant development and immunity. The rice genome contains two SERK genes, OsSerk1 and OsSerk2. We previously demonstrated that OsSerk2 is required for rice Xa21‐mediated resistance to Xanthomonas oryzae pv. oryzae (Xoo) and for normal development. Here we report the molecular characterization of OsSerk1. Overexpres-sion of OsSerk1 results in a semi‐dwarf phenotype whereas silencing of OsSerk1 results in a reduced angle of the lamina joint. OsSerk1 is not required for rice resistance to Xoo or Magnaporthe oryzae. Overexpression of OsSerk1 in OsSerk2‐silenced lines complements phenotypes associated with brassinosteroid (BR) signaling defects, but not the disease resistance phenotype mediated by Xa21. In yeast, OsSERK1 interacts with itself forming homodimers, and also interacts with the kinase domains of OsSERK2 and BRI1, respectively. OsSERK1 is a functional protein kinase capable of auto‐phosphorylation in vitro. We conclude that, whereas OsSERK2 regulates both rice development and immunity, OsSERK1 functions in rice development but not immunity to Xoo and M. oryzae.

  9. Bypassing both surface attachment and surface recognition requirements for appressorium formation by overactive ras signaling in Magnaporthe oryzae.

    Science.gov (United States)

    Zhou, Xiaoying; Zhao, Xinhua; Xue, Chaoyang; Dai, Yafeng; Xu, Jin-Rong

    2014-09-01

    Magnaporthe oryzae forms a highly specialized infection structure called an appressorium for plant penetration. In M. oryzae and many other plant-pathogenic fungi, surface attachment and surface recognition are two essential requirements for appressorium formation. Development of appressoria in the air has not been reported. In this study, we found that expression of a dominant active MoRAS2(G18V) allele in M. oryzae resulted in the formation of morphologically abnormal appressoria on nonconducive surfaces, in liquid suspensions, and on aerial hyphae without attachment to hard surfaces. Both the Pmk1 mitogen-activated protein kinase cascade and cAMP signaling pathways that regulate surface recognition and appressorium morphogenesis in M. oryzae were overactivated in the MoRAS2(G18V) transformant. In mutants deleted of PMK1 or CPKA, expression of MoRAS2(G18V) had no significant effects on appressorium morphogenesis. Furthermore, expression of dominant MoRAS2 in Colletotrichum graminicola and C. gloeosporioides also caused the formation of appressorium-like structures in aerial hyphae. Overall, our data indicate that MoRas2 functions upstream from both the cAMP-PKA and Pmk1 pathways and overactive Ras signaling leads to improper activation of these two pathways and appressorium formation without surface attachment in appressorium-forming pathogens.

  10. Evolution of Compatibility Range in the Rice-Magnaporthe oryzae System: An Uneven Distribution of R Genes Between Rice Subspecies.

    Science.gov (United States)

    Gallet, Romain; Fontaine, Colin; Bonnot, François; Milazzo, Joëlle; Tertois, Christophe; Adreit, Henri; Ravigné, Virginie; Fournier, Elisabeth; Tharreau, Didier

    2016-04-01

    Efficient strategies for limiting the impact of pathogens on crops require a good understanding of the factors underlying the evolution of compatibility range for the pathogens and host plants, i.e., the set of host genotypes that a particular pathogen genotype can infect and the set of pathogen genotypes that can infect a particular host genotype. Until now, little is known about the evolutionary and ecological factors driving compatibility ranges in systems implicating crop plants. We studied the evolution of host and pathogen compatibility ranges for rice blast disease, which is caused by the ascomycete Magnaporthe oryzae. We challenged 61 rice varieties from three rice subspecies with 31 strains of M. oryzae collected worldwide from all major known genetic groups. We determined the compatibility range of each plant variety and pathogen genotype and the severity of each plant-pathogen interaction. Compatibility ranges differed between rice subspecies, with the most resistant subspecies selecting for pathogens with broader compatibility ranges and the least resistant subspecies selecting for pathogens with narrower compatibility ranges. These results are consistent with a nested distribution of R genes between rice subspecies.

  11. Screening of a synthetic peptide combinatorial library to identify inhibitors of the appressorium formation in Magnaporthe oryzae.

    Science.gov (United States)

    Rebollar, Aarón; Marcos, Jose F; López-García, Belén

    2014-11-01

    The rice blast disease caused by Magnaporthe oryzae is one of the most devastating diseases of cultivated rice. One of the most important stages in the infective cycle of M. oryzae is the formation of the dome-shaped structure called appressorium. The purpose of the present study was to identify novel peptides to control the rice blast disease by blocking the appressorium formation through screening of a synthetic peptide combinatorial library. As result of the screening, a set of 29 putative bioactive peptides were identified, synthesized and assayed in comparison with the previously identified peptide PAF104. The peptides MgAPI24, MgAPI40 and MgAPI47 showed improved inhibitory activity on the M. oryzae appressorium formation. Our data show that these peptides have a differential effect on two developmental structures: appressoria and appressorium-like structures. Antimicrobial assays against M. oryzae and other non-target microorganisms showed a weak or no toxicity of these peptides, demonstrating their specific activity blocking the appressorium formation. Therefore, the outcome of this research would be useful in the development of novel target-oriented peptides to use in plant protection.

  12. Lysimachia foenum-graecum Herba Extract, a Novel Biopesticide, Inhibits ABC Transporter Genes and Mycelial Growth of Magnaporthe oryzae

    Directory of Open Access Journals (Sweden)

    Youngjin Lee

    2016-02-01

    Full Text Available To identify a novel biopesticide controlling rice blast disease caused by Magnaporthe oryzae, 700 plant extracts were evaluated for their inhibitory effects on mycelial growth of M. oryzae. The L. foenum-graecum Herba extract showed the lowest inhibition concentration (IC₅₀ of 39.28 μg/ml, which is lower than the IC₅₀ of blasticidin S (63.06 μg/ml, a conventional fungicide for rice blast disease. When treatments were combined, the IC₅₀ of blasticidin S was dramatically reduced to 10.67 μg/ml. Since ABC transporter genes are involved in fungicide resistance of many organisms, we performed RT-PCR to investigate the transcriptional changes of 40 ABC transporter family genes of M. oryzae treated with the plant extract, blasticidin S, and tetrandrine, a recognized ABC transporter inhibitor. Four ABC transporter genes were prominently activated by blasticidin S treatment, but were suppressed by combinational treatment of blasticidin S with the plant extract, or with tetrandrine that didn’t show cellular toxicity by itself in this study. Mycelial death was detected via confocal microscopy at 24 h after plant extract treatment. Finally, subsequent rice field study revealed that the plant extract had high control efficacy of 63.3% and should be considered a biopesticide for rice blast disease. These results showed that extract of L. foenum graecum Herba suppresses M. oryzae ABC transporter genes inducing mycelial death and therefore may be a potent novel biopesticide.

  13. Induction of avirulence by AVR-Pita1 in virulent U.S. field isolates of Magnaporthe oryzae’

    Institute of Scientific and Technical Information of China (English)

    Yuntao; Dai; Eugenia; Winston; James; C.Correll; Yulin; Jia

    2014-01-01

    The AVR-Pita1 gene,from the Chinese isolate O-137 of Magnaporthe oryzae,is an effector that determines the efficacy of the Pi-ta rice blast resistance gene.In the present study,the avirulence function of AVR-Pita1 was induced by transformation of field isolates(TM2,ZN19,B2 and B8)that originally were collected from the U.S.and are virulent on Pi-ta-carrying rice cultivars.The presence of AVR-Pita1 from O-137 in independent transformants was detected by PCR using AVR-Pita1 specific primers and verified by DNA sequencing and Southern blot analysis using the AVR-Pita1 coding region as a probe.The results of pathogenicity assays showed that the AVR-Pita1-transformed isolates were not able to infect rice cultivars Katy and Drew carrying Pi-ta.Control isolates that were transformed with inserts lacking the AVR-Pita1gene remained virulent.Our findings demonstrate that AVR-Pita1 can be used to induce novel gene-specific blast resistance in nature.

  14. Roles of Forkhead-box Transcription Factors in Controlling Development, Pathogenicity, and Stress Response in Magnaporthe oryzae

    Directory of Open Access Journals (Sweden)

    Jaejin Park

    2014-06-01

    Full Text Available Although multiple transcription factors (TFs have been characterized via mutagenesis to understand their roles in controlling pathogenicity and infection-related development in Magnaporthe oryzae, the causal agent of rice blast, if and how forkhead-box (FOX TFs contribute to these processes remain to be characterized. Four putative FOX TF genes were identified in the genome of M. oryzae, and phylogenetic analysis suggested that two of them (MoFKH1 and MoHCM1 correspond to Ascomycota-specific members of the FOX TF family while the others (MoFOX1 and MoFOX2 are Pezizomycotina-specific members. Deletion of MoFKH1 (ΔMofkh1 resulted in reduced mycelial growth and conidial germination, abnormal septation and stress response, and reduced virulence. Similarly, ΔMohcm1 exhibited reduced mycelial growth and conidial germination. Conidia of ΔMofkh1 and ΔMohcm1 were more sensitive to one or both of the cell cycle inhibitors hydroxyurea and benomyl, suggesting their role in cell cycle control. On the other hand, loss of MoFOX1 (ΔMofox1 did not show any noticeable changes in development, pathogenicity, and stress response. Deletion of MoFOX2 was not successful even after repeated attempts. Taken together, these results suggested that MoFKH1 and Mo-HCM1 are important in fungal development and that MoFKH1 is further implicated in pathogenicity and stress response in M. oryzae.

  15. Nuclear flow in a filamentous fungus

    CERN Document Server

    Hickey, Patrick C; Read, Nick; Glass, N Louise; Roper, Marcus

    2012-01-01

    The syncytial cells of a filamentous fungus consist of a mass of growing, tube-like hyphae. Each extending tip is fed by a continuous flow of nuclei from the colony interior, pushed by a gradient in turgor pressure. The myco-fluidic flows of nuclei are complex and multidirectional, like traffic in a city. We map out the flows in a strain of the model filamentous fungus {\\it N. crassa} that has been transformed so that nuclei express either hH1-dsRed (a red fluorescent nuclear protein) or hH1-GFP (a green-fluorescent protein) and report our results in a fluid dynamics video.

  16. Open-Ended Experimentation with the Fungus Pilobolus.

    Science.gov (United States)

    Coble, Charles R.; Bland, Charles E.

    This paper describes open-ended experimentation with the fungus Pilobolus for laboratory work by high school students. The fungus structure and reproduction is described and sources of the fungus are suggested. Four areas for investigation are suggested: the effect of a diffuse light source, the effect of a point light source, the effect of light…

  17. Molecular dynamics of interactions of rice with rice blast and sheath blight pathogens

    Science.gov (United States)

    In an effort to develop the molecular strategies to control rice (Oryzae sativa) diseases, molecular interactions of rice with rice blast [Magnaporthe oryzae, formerly (Magnaporthe grisea] and sheath blight (Rhizoctonia solani) fungi were analyzed. The interaction of rice with M. oryzae follows a b...

  18. Resolving the polyphyletic nature of Pyricularia (Pyriculariaceae)

    NARCIS (Netherlands)

    Klaubauf, S.; Tharreau, D.; Fournier, E.; Groenewald, J.Z.; Crous, P.W.; Vries, de R.P.; Lebrun, M.H.

    2014-01-01

    Species of Pyricularia (magnaporthe-like sexual morphs) are responsible for major diseases on grasses. Pyricularia oryzae (sexual morph Magnaporthe oryzae) is responsible for the major disease of rice called rice blast disease, and foliar diseases of wheat and millet, while Pyricularia grisea (sexua

  19. Solanapyrone analogues from a Hawaiian fungicolous fungus

    Science.gov (United States)

    Four new solanayrone analogues (solanapyrones J-M; 1-4) have been isolated from an unidentified fungicolous fungus collected in Hawaii. The structures and relative configurations of these compounds were determined by analysis of ID NMR, 2D NMR, and MS data. Solanapyrone J(1) showed antifungal acti...

  20. Death from Fungus in the Soil

    Centers for Disease Control (CDC) Podcasts

    2012-12-17

    Dr. Shira Shafir, Assistant Professor of Epidemiology at the UCLA Fielding School of Public Health, discusses her study about fungus found in soil.  Created: 12/17/2012 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 12/18/2012.

  1. Spread of Rare Fungus from Vancouver Island

    Centers for Disease Control (CDC) Podcasts

    2006-12-20

    Cryptococcus gattii, a rare fungus normally found in the tropics, has infected people and animals on Vancouver Island, Canada. Dr. David Warnock, Director, Division of Foodborne, Bacterial, and Mycotic Diseases, CDC, discusses public health concerns about further spread of this organism.  Created: 12/20/2006 by Emerging Infectious Diseases.   Date Released: 12/29/2006.

  2. Renal fungus ball: a challenging clinical problem.

    Science.gov (United States)

    Tan, Wei Phin; Turba, Ulku C; Deane, Leslie A

    2017-04-28

    We describe a case of renal pelvi-ureteric fungus ball managed with placement of two nephrostomy tubes and amphotericin B irrigation through a nephrostomy tube with the other to free drain. A 46-year-old man with uncontrolled Type 2 diabetes mellitus was referred to the urology clinic for workup of recurrent urinary tract infection. Urine culture grew Candida albicans. The patient was started on oral fluconazole therapy. Cystoscopy and cystogram revealed a grade 3 left vesicoureteral reflux and right retrograde pyelogram revealed a filling defect in the right renal pelvis extending into the proximal ureter with severe hydroureteronephrosis. Two nephrostomy tubes were placed (mid-pole and lower pole) to ensure that the system was not obstructed. Amphotericin B (50 mg/1000 ml normal saline) irrigation was then instilled through the mid-pole nephrostomy tube at a rate of 30 ml/h with the lower pole nephrostomy tube to free drain. An antegrade nephrostogram was performed after 5 days of amphotericin B instillation, showing complete resolution of the fungus ball. The patient is awaiting definitive minimally invasive management of the distal ureteral narrowing. Renal and pelvi-ureteric fungus ball is a challenging clinical entity. It must be addressed promptly and efficiently to be successful. We describe a minimally invasive approach that was tolerated well and resulted in complete clearance of the fungus ball in a relatively short time frame.

  3. Rock phosphate solubilization by the ectomycorrhizal fungus ...

    African Journals Online (AJOL)

    SAM

    2014-06-18

    Jun 18, 2014 ... Despite this, a large proportion (75 to 90%) of fertilizer P .... nitrogen salts such as Urea, KNO3, NaNO3, NH4Cl, NaNO2 (Figure. 2). Phospholytic activity of fungus along with MHB strains without any carbon and nitrogen sources acted as control and .... complexity of CaP chemistry, release of microbial.

  4. 纳米SiO2对水稻稻瘟病的抗病效应及对水稻生长发育的影响%Effects of Nano-silica on Rice's Resistance to Magnaporthe oryzae and on Rice Growth

    Institute of Scientific and Technical Information of China (English)

    刘俊渤; 常海波; 马景勇; 唐珊珊; 齐静芝

    2012-01-01

    Using nano-silica as silicon source, disease-resistant varieties "NongDa 18" and susceptible varieties "Mongolian rice" as material, the experiment determined the role of the nano-silica on rice's resistance to magnaporthe grisea and its effect on rice growth. The results show that the disease indexes of the disease-resistant varieties and susceptible varieties with nano-silica treatment respectively decreased by 30.98% and 51.03% compared with those without silicon processing. The relative control effect of disease-resistance varieties achieved 54.93% , while the susceptible varieties reached 73.47% . Silicon application reduced the disease level and index, strengthened the resistance to rice blast, particularly among the susceptible Mongolian rice. Nano-silica application to rice can not only significantly improve the content of chlorophyll, the net photosynthetic rate, stomatal conductance and intercellular carbon dioxide concentration, which help to enhance the photosynthesis of rice leaf, but can also increase the number of new roots and its longest length and improve the active absorption area and the vigor of roots. At the same time, it can also increase the contact angle of rice leaves and reduce the leaf angle and the attachment of fungi. In short, it is good for normal rice growth.%以纳米SiO2为硅源,以抗稻瘟病的水稻品种“农大18号”和感稻瘟病的水稻品种“蒙古稻”为材料,测定了纳米SiO2对水稻抗瘟效应及水稻生长发育的影响.试验结果表明:纳米SiO2处理的抗病品种和感病品种的病情指数分别比不施硅处理下降了30.98%和51.03%,抗病品种的相对防治效果达到了54.93%,而感病品种的相对防治效果达到了73.47%.施硅减轻了病级和病情指数,增强了水稻对稻瘟病的抗性,在感病品种“蒙古稻”上表现尤为明显.水稻在施用纳米SiO2后,不仅可显著提高叶片叶绿素含量,增大叶片净光合速率、气孔导度和胞间CO2

  5. Over-Expression of Rice CBS Domain Containing Protein, OsCBSX3, Confers Rice Resistance to Magnaporthe oryzae Inoculation.

    Science.gov (United States)

    Mou, Shaoliang; Shi, Lanping; Lin, Wei; Liu, Yanyan; Shen, Lei; Guan, Deyi; He, Shuilin

    2015-07-13

    Cystathionine β-synthase (CBS) domain containing proteins (CDCPs) constitute a big family in plants and some members in this family have been implicated in a variety of biological processes, but the precise functions and the underlying mechanism of the majority of this family in plant immunity remain to be elucidated. In the present study, a CBS domain containing protein gene, OsCBSX3, is functionally characterized in rice resistance against Magnaporthe oryzae (M. oryzae). By quantitative real-time PCR, transcripts of OsCBSX3 are up-regulated significantly by inoculation of M. oryzae and the exogenously applied salicylic acid (SA) and methyl jasmonate (MeJA). OsCBSX3 is exclusively localized to the plasma membrane by transient expression of OsCBSX3 fused to green fluorescent protein (GFP) through approach of Agrobacterium infiltration in Nicotiana benthamiana leaves. The plants of homozygous T3 transgenic rice lines of over-expressing OsCBSX3 exhibit significant enhanced resistance to M. oryzae inoculation, manifested by decreased disease symptoms, and inhibition of pathogen growth detected in DNA. Consistently, the over-expression of OsCBSX3 enhances the transcript levels of immunity associated marker genes including PR1a, PR1b, PR5, AOS2, PAL, NH1, and OsWRKY13 in plants inoculated with M. oryzae. These results suggest that OsCBSX3 acts as a positive regulator in resistance of rice to M. oryzae regulated by SA and JA-mediated signaling pathways synergistically.

  6. Over-Expression of Rice CBS Domain Containing Protein, OsCBSX3, Confers Rice Resistance to Magnaporthe oryzae Inoculation

    Directory of Open Access Journals (Sweden)

    Shaoling Mou

    2015-07-01

    Full Text Available Cystathionine β-synthase (CBS domain containing proteins (CDCPs constitute a big family in plants and some members in this family have been implicated in a variety of biological processes, but the precise functions and the underlying mechanism of the majority of this family in plant immunity remain to be elucidated. In the present study, a CBS domain containing protein gene, OsCBSX3, is functionally characterized in rice resistance against Magnaporthe oryzae (M. oryzae. By quantitative real-time PCR, transcripts of OsCBSX3 are up-regulated significantly by inoculation of M. oryzae and the exogenously applied salicylic acid (SA and methyl jasmonate (MeJA. OsCBSX3 is exclusively localized to the plasma membrane by transient expression of OsCBSX3 fused to green fluorescent protein (GFP through approach of Agrobacterium infiltration in Nicotiana benthamiana leaves. The plants of homozygous T3 transgenic rice lines of over-expressing OsCBSX3 exhibit significant enhanced resistance to M. oryzae inoculation, manifested by decreased disease symptoms, and inhibition of pathogen growth detected in DNA. Consistently, the over-expression of OsCBSX3 enhances the transcript levels of immunity associated marker genes including PR1a, PR1b, PR5, AOS2, PAL, NH1, and OsWRKY13 in plants inoculated with M. oryzae. These results suggest that OsCBSX3 acts as a positive regulator in resistance of rice to M. oryzae regulated by SA and JA-mediated signaling pathways synergistically.

  7. 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

  8. The late endosomal HOPS complex anchors active G-protein signaling essential for pathogenesis in magnaporthe oryzae.

    Directory of Open Access Journals (Sweden)

    Ravikrishna Ramanujam

    Full Text Available In Magnaporthe oryzae, the causal ascomycete of the devastating rice blast disease, the conidial germ tube tip must sense and respond to a wide array of requisite cues from the host in order to switch from polarized to isotropic growth, ultimately forming the dome-shaped infection cell known as the appressorium. Although the role for G-protein mediated Cyclic AMP signaling in appressorium formation was first identified almost two decades ago, little is known about the spatio-temporal dynamics of the cascade and how the signal is transmitted through the intracellular network during cell growth and morphogenesis. In this study, we demonstrate that the late endosomal compartments, comprising of a PI3P-rich (Phosphatidylinositol 3-phosphate highly dynamic tubulo-vesicular network, scaffold active MagA/GαS, Rgs1 (a GAP for MagA, Adenylate cyclase and Pth11 (a non-canonical GPCR in the likely absence of AKAP-like anchors during early pathogenic development in M. oryzae. Loss of HOPS component Vps39 and consequently the late endosomal function caused a disruption of adenylate cyclase localization, cAMP signaling and appressorium formation. Remarkably, exogenous cAMP rescued the appressorium formation defects associated with VPS39 deletion in M. oryzae. We propose that sequestration of key G-protein signaling components on dynamic late endosomes and/or endolysosomes, provides an effective molecular means to compartmentalize and control the spatio-temporal activation and rapid downregulation (likely via vacuolar degradation of cAMP signaling amidst changing cellular geometry during pathogenic development in M. oryzae.

  9. Cloning and functional validation of early inducible Magnaporthe oryzae responsive CYP76M7 promoter from rice

    Directory of Open Access Journals (Sweden)

    Joshitha eVijayan

    2015-05-01

    Full Text Available Cloning and functional characterization of plant pathogen inducible promoters is of great significance for their use in the effective management of plant diseases. The rice gene CYP76M7 was up regulated at 24, 48 and 72 hours post inoculation (hpi with two isolates of Magnaporthe oryzae Mo-ei-11 and Mo-ni-25. In this study, the promoter of CYP76M7 gene was cloned from rice cultivar HR-12, characterized and functionally validated. The Transcription Start Site of CYP76M7 was mapped at 45 bases upstream of the initiation codon. To functionally validate the promoter, 5′ deletion analysis of the promoter sequences was performed and the deletion fragments fused with the GUS reporter gene were used for generating stable transgenic Arabidopsis plants as well as for transient expression in rice. The spatial and temporal expression pattern of GUS in transgenic Arabidopsis plants and also in transiently expressed rice leaves revealed that the promoter of CYP76M7 gene was induced by M. oryzae. The induction of CYP76M7 promoter was observed at 24 hpi with M. oryzae. We report that, sequences spanning -222 bp to -520 bp, with the cluster of three W-boxes, two ASF1 motifs and a single GT-1 element may contribute to the M. oryzae inducible nature of CYP76M7 promoter. The promoter characterized in this study would be an ideal candidate for the overexpression of defence genes in rice for developing durable blast resistance rice lines.

  10. Evaluation of RNA extraction methods in rice and their application in expression analysis of resistance genes against Magnaporthe oryzae

    Directory of Open Access Journals (Sweden)

    Parisa Azizi

    2017-01-01

    Full Text Available Extraction of RNA of high quality and integrity is essential for gene expression studies and all downstream RNA-based techniques. The leaves of 16 merit Malaysian rice varieties were used to isolate total RNA using five different methods. The quantity, quality and integrity of extracted RNA were confirmed using three different means. The ratios of A260/280 ranged from 2.12 to 2.20. Electrophoresis (1.5% agarose gel was performed, illustrating intact and sharp bands representing the 28S, 18S, 5.8S and 5S ribosomal subunits of RNA, presenting intact RNA. RNA quality was verified using semi-quantitative polymerase chain reaction (sqPCR. The objective of this study was to identify different genes involved in the resistance of rice plants using high-quality RNA extracted 31 h after inoculation of Magnaporthe oryzae pathotype P7.2. The expression levels of eight blast resistance genes, Pikh, Pib, Pita, Pi21, Pi9, Os11gRGA8, OsWRKY22 and OsWRKY45, were evaluated by real-time PCR (RT-PCR. Real-time PCR was performed to identify candidate genes using RNA extracted by the TRIzol method, which showed the highest score compared with other methods in terms of RNA quantity, purity and integrity. In addition, the results of real-time PCR confirmed that the up-regulation of seven blast resistance genes may confer stronger resistance for the MR 276 variety against M. oryzae pathotype P7.2.

  11. Fungi have three tetraspanin families with distinct functions

    Science.gov (United States)

    Lambou, Karine; Tharreau, Didier; Kohler, Annegret; Sirven, Catherine; Marguerettaz, Mélanie; Barbisan, Crystel; Sexton, Adrienne C; Kellner, Ellen M; Martin, Francis; Howlett, Barbara J; Orbach, Marc J; Lebrun, Marc-Henri

    2008-01-01

    Background Tetraspanins are small membrane proteins that belong to a superfamily encompassing 33 members in human and mouse. These proteins act as organizers of membrane-signalling complexes. So far only two tetraspanin families have been identified in fungi. These are Pls1, which is required for pathogenicity of the plant pathogenic ascomycetes, Magnaporthe grisea, Botrytis cinerea and Colletotrichum lindemuthianum, and Tsp2, whose function is unknown. In this report, we describe a third family of tetraspanins (Tsp3) and a new family of tetraspanin-like proteins (Tpl1) in fungi. We also describe expression of some of these genes in M. grisea and a basidiomycete, Laccaria bicolor, and also their functional analysis in M. grisea. Results The exhaustive search for tetraspanins in fungal genomes reveals that higher fungi (basidiomycetes and ascomycetes) contain three families of tetraspanins (Pls1, Tsp2 and Tsp3) with different distribution amongst phyla. Pls1 is found in ascomycetes and basidiomycetes, whereas Tsp2 is restricted to basidiomycetes and Tsp3 to ascomycetes. A unique copy of each of PLS1 and TSP3 was found in ascomycetes in contrast to TSP2, which has several paralogs in the basidiomycetes, Coprinus cinereus and Laccaria bicolor. A tetraspanin-like family (Tpl1) was also identified in ascomycetes. Transcriptional analyses in various tissues of L. bicolor and M. grisea showed that PLS1 and TSP2 are expressed in all tissues in L. bicolor and that TSP3 and TPL1 are overexpressed in the sexual fruiting bodies (perithecia) and mycelia of M. grisea, suggesting that these genes are not pseudogenes. Phenotypic analysis of gene replacementmutants Δtsp3 and Δtpl1 of M. grisea revealed a reduction of the pathogenicity only on rice, in contrast to Δpls1 mutants, which are completely non-pathogenic on barley and rice. Conclusion A new tetraspanin family (Tsp3) and a tetraspanin-like protein family (Tpl1) have been identified in fungi. Functional analysis by gene

  12. Fungi have three tetraspanin families with distinct functions

    Directory of Open Access Journals (Sweden)

    Martin Francis

    2008-02-01

    Full Text Available Abstract Background Tetraspanins are small membrane proteins that belong to a superfamily encompassing 33 members in human and mouse. These proteins act as organizers of membrane-signalling complexes. So far only two tetraspanin families have been identified in fungi. These are Pls1, which is required for pathogenicity of the plant pathogenic ascomycetes, Magnaporthe grisea, Botrytis cinerea and Colletotrichum lindemuthianum, and Tsp2, whose function is unknown. In this report, we describe a third family of tetraspanins (Tsp3 and a new family of tetraspanin-like proteins (Tpl1 in fungi. We also describe expression of some of these genes in M. grisea and a basidiomycete, Laccaria bicolor, and also their functional analysis in M. grisea. Results The exhaustive search for tetraspanins in fungal genomes reveals that higher fungi (basidiomycetes and ascomycetes contain three families of tetraspanins (Pls1, Tsp2 and Tsp3 with different distribution amongst phyla. Pls1 is found in ascomycetes and basidiomycetes, whereas Tsp2 is restricted to basidiomycetes and Tsp3 to ascomycetes. A unique copy of each of PLS1 and TSP3 was found in ascomycetes in contrast to TSP2, which has several paralogs in the basidiomycetes, Coprinus cinereus and Laccaria bicolor. A tetraspanin-like family (Tpl1 was also identified in ascomycetes. Transcriptional analyses in various tissues of L. bicolor and M. grisea showed that PLS1 and TSP2 are expressed in all tissues in L. bicolor and that TSP3 and TPL1 are overexpressed in the sexual fruiting bodies (perithecia and mycelia of M. grisea, suggesting that these genes are not pseudogenes. Phenotypic analysis of gene replacementmutants Δtsp3 and Δtpl1 of M. grisea revealed a reduction of the pathogenicity only on rice, in contrast to Δpls1 mutants, which are completely non-pathogenic on barley and rice. Conclusion A new tetraspanin family (Tsp3 and a tetraspanin-like protein family (Tpl1 have been identified in fungi

  13. Ant-fungus species combinations engineer physiological activity of fungus gardens.

    Science.gov (United States)

    Seal, J N; Schiøtt, M; Mueller, U G

    2014-07-15

    Fungus-gardening insects are among the most complex organisms because of their extensive co-evolutionary histories with obligate fungal symbionts and other microbes. Some fungus-gardening insect lineages share fungal symbionts with other members of their lineage and thus exhibit diffuse co-evolutionary relationships, while others exhibit little or no symbiont sharing, resulting in host-fungus fidelity. The mechanisms that maintain this symbiont fidelity are currently unknown. Prior work suggested that derived leaf-cutting ants in the genus Atta interact synergistically with leaf-cutter fungi (Attamyces) by exhibiting higher fungal growth rates and enzymatic activities than when growing a fungus from the sister-clade to Attamyces (so-called 'Trachymyces'), grown primarily by the non-leaf cutting Trachymyrmex ants that form, correspondingly, the sister-clade to leaf-cutting ants. To elucidate the enzymatic bases of host-fungus specialization in leaf-cutting ants, we conducted a reciprocal fungus-switch experiment between the ant Atta texana and the ant Trachymyrmex arizonensis and report measured enzymatic activities of switched and sham-switched fungus gardens to digest starch, pectin, xylan, cellulose and casein. Gardens exhibited higher amylase and pectinase activities when A. texana ants cultivated Attamyces compared with Trachymyces fungi, consistent with enzymatic specialization. In contrast, gardens showed comparable amylase and pectinase activities when T. arizonensis cultivated either fungal species. Although gardens of leaf-cutting ants are not known to be significant metabolizers of cellulose, T. arizonensis were able to maintain gardens with significant cellulase activity when growing either fungal species. In contrast to carbohydrate metabolism, protease activity was significantly higher in Attamyces than in Trachymyces, regardless of the ant host. Activity of some enzymes employed by this symbiosis therefore arises from complex interactions between the

  14. Otimização das condições de cultivo de \\'Humicola grisea\\' var. \\'thermoidea\\', visando produção e isolamento de metabólitos secundários biológicamente ativos

    OpenAIRE

    Willian Jonis Andrioli

    2008-01-01

    O fungo Humicola grisea var. thermoidea foi submetido a diferentes condições de cultivo com o intuito de determinarem-se as melhores condições para produção de conídios, crescimento e produção de metabólitos secundários com atividade biológica. Para tal foram desenvolvidos experimentos avaliando dois parâmetros: meio fermentativo e tempo de incubação. Os meios fermentativos líquidos utilizados foram Czapek, Jackson e Vogel em condições de agitação (120 rpm), e os tempos avaliados foram 72, 96...

  15. Pulmonary infections by the fungus aspergillus

    Directory of Open Access Journals (Sweden)

    Rao P

    1979-01-01

    Full Text Available Five cases of respiratory infection by Aspergillus fumigates are described. Species of aspergillus is ubiquitous in nature. Therefore, repeated demonstration of fungus, serological evidence tend radiological findings are essential for diagnosis. Potassium iodide is a useful drug in aspergillus infection of the lung when other drugs are not available. Injection Emetine hydrochloride is promising as a therapeutic agent in pulmonary aspergillosis, where the lung parenchyma is involved.

  16. Antimicrobial constituents from endophytic fungus Fusarium sp.

    Directory of Open Access Journals (Sweden)

    Hidayat Hussain

    2015-03-01

    Full Text Available Objective: To evaluate the antimicrobial potential of fraction of the fungus Fusarium sp. and study the tentative identification of their active constituents. Methods: Six compounds were purified from an fraction of endophytic fungus Fusarium sp. using column chromatography and their structures have been confirmed based on 1H and 13C nuclear magnetic resonance spectra, distortionless enhancement by polarization transfer, 2D COSY, heteronuclear multiple quantum correlation and heteronuclear multiple bond correlation experiments. The six isolated compounds were screened for antimicrobial activity using the agar well diffusion method. Results: Phytochemical investigation of endophytic fungus Fusarium sp. lead to the isolation and identification of the following compounds viz., colletorin B, colletochlorin B, LL-Z1272β (llicicolin B, 4,5-dihydroascochlorin, ascochlorin, and 4,5-dihydrodechloroascochlorin. Colletorin B and colletochlorin B displayed moderate herbicidal, antifungal and antibacterial activities towards Chlorella fusca, Ustilago violacea, Fusarium oxysporum, and Bacillus megaterium. On the other hand LL-Z1272β (llicicolin B showed moderate antifungal activity towards Ustilago violacea and Fusarium oxysporum while 4,5-dihydroascochlorin showed strong antibacterial activity towards Bacillus megaterium. Furthermore, 4,5-dihydrodechloroascochlorin showed very strong antifungal activity towards Eurotium repens. Conclusions: Antimicrobial activities demonstrated by five of the six isolated compounds clearly demonstrate that these fungi extracts and active compounds present a great potential for the food, cosmetic and pharmaceutical industries.

  17. Purification and antifungal activity of a basic 34 kDa beta-1,3-glucanase from soybean hypocotyls inoculated with Phytophthora sojae f. sp. glycines.

    Science.gov (United States)

    Yi, S Y; Hwang, B K

    1997-06-30

    Inoculation of soybean (Glycine max L. cv. Jangyup) hypocotyls with Phytophthora sojae f. sp. glycines results in a marked accumulation of some pathogenesis-related (PR) proteins. A basic beta-1,3-glucanase (34 kDa) was purified from soybean hypocotyls infected by an incompatible race of P. sojae f. sp. glycines using CM-cellulose cation exchange chromatography and Bio-gel P-60 gel filtration. The purified soybean beta-1,3-glucanase cross-reacted with polyclonal antibody raised against a tomato beta-1,3-glucanase. The activity of beta-1,3-glucanase was much higher in the infected soybean hypocotyls than the healthy ones. The beta-1, 3-glucanase purified from soybean inhibited spore germination and hyphal growth of the chitin-negative fungus P. sojae f. sp. glycines, but did not show any antifungal activity against the chitin-containing fungi Alternaria mali, Colletotrichum gloeosporioides, and Magnaporthe grisea.

  18. Structures and functions of oligosaccharins. Progress report, June 15, 1993--March 14, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Albersheim, P.

    1995-03-01

    This research focuses on the following: Purification, characterization, and cell wall localization of an {alpha}-fucosidase that inactivates a xyloglucan oligosaccharin; Oligogalacturonides inhibit the formation of roots on tobacco explants; Activation of a tobacco glycine-rich protein gene by a fungal glucan preparation; Fusarium moniliforme secretes four endopolygalacturonases derived from a single gene product; Polygalacturonase-inhibiting protein accumulates in Phaseolus vulgaris L. in response to wounding, elicitors and fungal infection; Generation of {beta}-glucan elicitors by plant enzymes and inhibition of the enzymes by a fungal protein; Polygalacturonase inhibitor proteins from bean (Phaseolus vulgaris L.), pear (Pyrus communis L.) and tomato (Lycopersicon esculentum): Immunological relatedness and specificity of polygalacturonase inhibition; Fungi protect themselves against plant pathogenesis-related glycanases; Purification, cloning, and characterization of two xylanases from Magnaporthe grisea, the rice blast fungus; and Molecular cloning and expression pattern of an {alpha}-fucosidase gene from pea seedlings.

  19. RAPD-based screening of genomic libraries for positional cloning.

    Science.gov (United States)

    Dioh, W; Tharreau, D; Lebrun, M H

    1997-12-15

    RAPD markers are frequently used for positional cloning. However, RAPD markers often contain repeated sequences which prevent genomic library screening by hybridisation. We have developed a simple RAPD analysis of genomic libraries based on the identification of cosmid pools and clones amplifying the RAPD marker of interest. Our method does not require the cloning or characterisation of the RAPD marker as it relies on the analysis of cosmid pools or clones using a simple RAPD protocol. We applied this strategy using four RAPD markers composed of single copy or repeated sequences linked to avirulence genes of the rice blast fungus Magnaporthe grisea . Cosmids containing these RAPD markers were easily and rapidly identified allowing the construction of physical contigs at these loci.

  20. Inhibition of fungal spore adhesion by zosteric Acid as the basis for a novel, nontoxic crop protection technology.

    Science.gov (United States)

    Stanley, Michele S; Callow, Maureen E; Perry, Ruth; Alberte, Randall S; Smith, Robert; Callow, James A

    2002-04-01

    ABSTRACT To explore the potential for nontoxic crop protection technologies based on the inhibition of fungal spore adhesion, we have tested the effect of synthetic zosteric acid (p-(sulfo-oxy) cinnamic acid), a naturally occurring phenolic acid in eelgrass (Zostera marina L.) plants, on spore adhesion and infection in two pathosystems: rice blast caused by Magnaporthe grisea and bean anthracnose caused by Colletotrichum lindemuthianum. We have shown that zosteric acid inhibits spore adhesion to model and host leaf surfaces and that any attached spores fail to develop appressoria, and consequently do not infect leaf cells. Low concentrations of zosteric acid that are effective in inhibiting adhesion are not toxic to either fungus or to the host. The inhibition of spore adhesion in the rice blast pathogen is fully reversible. On plants, zosteric acid reduced (rice) or delayed (bean) lesion development. These results suggest that there is potential for novel and environmentally benign crop protection technologies based on manipulating adhesion.

  1. Robust-LongSAGE (RL-SAGE): an improved LongSAGE method for high-throughput transcriptome analysis.

    Science.gov (United States)

    Gowda, Malali; Wang, Guo-Liang

    2008-01-01

    Serial analysis of gene expression (SAGE) is a powerful technique for large-scale transcriptome analysis in eukaryotes. However, technical difficulties in the SAGE library construction, such as low concatemer cloning efficiency, small concatemer size, and a high level of empty clones, has prohibited its widespread use as a routine technique for expression profiling in many laboratories. We recently improved the LongSAGE library construction method considerably and developed a modified version called Robust-LongSAGE, or RL-SAGE. In RL-SAGE, concatemer cloning efficiency and clone insert size were increased significantly. About 20 PCR reactions are sufficient to make a library with more than 150,000 clones. Using RL-SAGE, we have made 10 libraries of rice, maize, and the rice blast fungus Magnaporthe grisea.

  2. The Cyclase-associated protein Cap1 is important for proper regulation of infection-related morphogenesis in Magnaporthe oryzae.

    Directory of Open Access Journals (Sweden)

    Xiaoying Zhou

    2012-09-01

    Full Text Available Surface recognition and penetration are critical steps in the infection cycle of many plant pathogenic fungi. In Magnaporthe oryzae, cAMP signaling is involved in surface recognition and pathogenesis. Deletion of the MAC1 adenylate cyclase gene affected appressorium formation and plant infection. In this study, we used the affinity purification approach to identify proteins that are associated with Mac1 in vivo. One of the Mac1-interacting proteins is the adenylate cyclase-associated protein named Cap1. CAP genes are well-conserved in phytopathogenic fungi but none of them have been functionally characterized. Deletion of CAP1 blocked the effects of a dominant RAS2 allele and resulted in defects in invasive growth and a reduced intracellular cAMP level. The Δcap1 mutant was defective in germ tube growth, appressorium formation, and formation of typical blast lesions. Cap1-GFP had an actin-like localization pattern, localizing to the apical regions in vegetative hyphae, at the periphery of developing appressoria, and in circular structures at the base of mature appressoria. Interestingly, Cap1, similar to LifeAct, did not localize to the apical regions in invasive hyphae, suggesting that the apical actin cytoskeleton differs between vegetative and invasive hyphae. Domain deletion analysis indicated that the proline-rich region P2 but not the actin-binding domain (AB of Cap1 was responsible for its subcellular localization. Nevertheless, the AB domain of Cap1 must be important for its function because CAP1(ΔAB only partially rescued the Δcap1 mutant. Furthermore, exogenous cAMP induced the formation of appressorium-like structures in non-germinated conidia in CAP1(ΔAB transformants. This novel observation suggested that AB domain deletion may result in overstimulation of appressorium formation by cAMP treatment. Overall, our results indicated that CAP1 is important for the activation of adenylate cyclase, appressorium morphogenesis, and plant

  3. The Cyclase-associated protein Cap1 is important for proper regulation of infection-related morphogenesis in Magnaporthe oryzae.

    Science.gov (United States)

    Zhou, Xiaoying; Zhang, Haifeng; Li, Guotian; Shaw, Brian; Xu, Jin-Rong

    2012-09-01

    Surface recognition and penetration are critical steps in the infection cycle of many plant pathogenic fungi. In Magnaporthe oryzae, cAMP signaling is involved in surface recognition and pathogenesis. Deletion of the MAC1 adenylate cyclase gene affected appressorium formation and plant infection. In this study, we used the affinity purification approach to identify proteins that are associated with Mac1 in vivo. One of the Mac1-interacting proteins is the adenylate cyclase-associated protein named Cap1. CAP genes are well-conserved in phytopathogenic fungi but none of them have been functionally characterized. Deletion of CAP1 blocked the effects of a dominant RAS2 allele and resulted in defects in invasive growth and a reduced intracellular cAMP level. The Δcap1 mutant was defective in germ tube growth, appressorium formation, and formation of typical blast lesions. Cap1-GFP had an actin-like localization pattern, localizing to the apical regions in vegetative hyphae, at the periphery of developing appressoria, and in circular structures at the base of mature appressoria. Interestingly, Cap1, similar to LifeAct, did not localize to the apical regions in invasive hyphae, suggesting that the apical actin cytoskeleton differs between vegetative and invasive hyphae. Domain deletion analysis indicated that the proline-rich region P2 but not the actin-binding domain (AB) of Cap1 was responsible for its subcellular localization. Nevertheless, the AB domain of Cap1 must be important for its function because CAP1(ΔAB) only partially rescued the Δcap1 mutant. Furthermore, exogenous cAMP induced the formation of appressorium-like structures in non-germinated conidia in CAP1(ΔAB) transformants. This novel observation suggested that AB domain deletion may result in overstimulation of appressorium formation by cAMP treatment. Overall, our results indicated that CAP1 is important for the activation of adenylate cyclase, appressorium morphogenesis, and plant infection in M

  4. Decomposition of Plant Debris by the Nematophagous Fungus ARF

    OpenAIRE

    Wang, Kening; Riggs, R. D.; Crippen, Devany

    2004-01-01

    In the study of the biological control of plant-parasitic nematodes, knowledge of the saprophytic ability of a nematophagous fungus is necessary to understand its establishment and survival in the soil. The objectives of this study were (i) to determine if the nematophagous fungus ARF (Arkansas Fungus) shows differential use of plant residues; and (ii) to determine if ARF still existed in the soil of a field in which ARF was found originally and in which the population level of Heterodera gly...

  5. Symbiotic fungi produce laccases potentially involved in phenol degradation in fungus combs of fungus-growing termites in Thailand.

    Science.gov (United States)

    Taprab, Yaovapa; Johjima, Toru; Maeda, Yoshimasa; Moriya, Shigeharu; Trakulnaleamsai, Savitr; Noparatnaraporn, Napavarn; Ohkuma, Moriya; Kudo, Toshiaki

    2005-12-01

    Fungus-growing termites efficiently decompose plant litter through their symbiotic relationship with basidiomycete fungi of the genus Termitomyces. Here, we investigated phenol-oxidizing enzymes in symbiotic fungi and fungus combs (a substrate used to cultivate symbiotic fungi) from termites belonging to the genera Macrotermes, Odontotermes, and Microtermes in Thailand, because these enzymes are potentially involved in the degradation of phenolic compounds during fungus comb aging. Laccase activity was detected in all the fungus combs examined as well as in the culture supernatants of isolated symbiotic fungi. Conversely, no peroxidase activity was detected in any of the fungus combs or the symbiotic fungal cultures. The laccase cDNA fragments were amplified directly from RNA extracted from fungus combs of five termite species and a fungal isolate using degenerate primers targeting conserved copper binding domains of basidiomycete laccases, resulting in a total of 13 putative laccase cDNA sequences being identified. The full-length sequences of the laccase cDNA and the corresponding gene, lcc1-2, were identified from the fungus comb of Macrotermes gilvus and a Termitomyces strain isolated from the same fungus comb, respectively. Partial purification of laccase from the fungus comb showed that the lcc1-2 gene product was a dominant laccase in the fungus comb. These findings indicate that the symbiotic fungus secretes laccase to the fungus comb. In addition to laccase, we report novel genes that showed a significant similarity with fungal laccases, but the gene product lacked laccase activity. Interestingly, these genes were highly expressed in symbiotic fungi of all the termite hosts examined.

  6. Metabolites from mangrove endophytic fungus Dothiorella sp.

    Institute of Scientific and Technical Information of China (English)

    XUQingyan; WANGJianfeng; HUANGYaojian; ZHENGZhonghui; SONGSiyang; ZHANGYongmin; SUWenjin

    2004-01-01

    Mangroves are special woody plant communities in the intertidal zone of tropical and subtropical coasts. They prove to be a natural microorganisms and new metabolites storage. In the study of mangrove endophytic fungi metabolites, four new compounds, Compounds 1, 2, 3 and 4, as well as a known octaketide, cytosporone B (5), are isolated from an endophytic fungus, Dothiorella sp., HTF3. They all show cytotoxic activities. The elucidation of these structures is mainly based on 1D/2D NMR and ESI-MS spectral analyses.

  7. Sterols from the Fungus Catathelasma imperiale

    Institute of Scientific and Technical Information of China (English)

    YANG, Sheng-Ping; XU, Jun; YUE, Jian-Min

    2003-01-01

    Eight ergostane-type sterols and three their derivatives (one mono-linoleate and two mono-glucosides) were isolated from the ethyl acetate soluble fraction of the fungus Catathelasma imperiale. Two of them are novel compounds, namely 22E, 24R-ergosta-7,22-diene-3β, 5α-diol-6β-linoleate (1) and 22E, 24R-ergosta-7,22-diene-3β,5β,6α-triol (5) with an uncommon cisfused A/B ring. Structures of these compounds were demonstrated on the basis of their chemical evidences and spectroscopic methods, especially 2D NMR techniques.

  8. Reciprocal genomic evolution in the ant-fungus agricultural symbiosis

    DEFF Research Database (Denmark)

    Nygaard, Sanne; Hu, Haofu; Li, Cai;

    2016-01-01

    The attine ant-fungus agricultural symbiosis evolved over tens of millions of years, producing complex societies with industrial-scale farming analogous to that of humans. Here we document reciprocal shifts in the genomes and transcriptomes of seven fungus-farming ant species and their fungal cul...

  9. Fungus-associated bacteriome in charge of their host behaviour

    NARCIS (Netherlands)

    Schulz-Bohm, Kristin; Tyc, Olaf; Boer, Wietse de; Peereboom, Nils; Debets, Fons; Zaagman, Niels; Janssens, Thierry K.S.; Garbeva, Paolina

    2017-01-01

    Abstract Bacterial-fungal interactions are widespread in nature and there is a growing number of studies reporting distinct fungus-associated bacteria. However, little is known so far about how shifts in the fungus-associated bacteriome will affect the fungal host’s lifestyle. In the present study,

  10. Genome Sequence of the Pathogenic Fungus Sporothrix schenckii (ATCC 58251).

    Science.gov (United States)

    Cuomo, Christina A; Rodriguez-Del Valle, Nuri; Perez-Sanchez, Lizaida; Abouelleil, Amr; Goldberg, Jonathan; Young, Sarah; Zeng, Qiandong; Birren, Bruce W

    2014-05-22

    Sporothrix schenckii is a pathogenic dimorphic fungus that grows as a yeast and as mycelia. This species is the causative agent of sporotrichosis, typically a skin infection. We report the genome sequence of S. schenckii, which will facilitate the study of this fungus and of the Sporothrix schenckii group.

  11. Reciprocal genomic evolution in the ant-fungus agricultural symbiosis

    DEFF Research Database (Denmark)

    Nygaard, Sanne; Hu, Haofu; Li, Cai

    2016-01-01

    The attine ant-fungus agricultural symbiosis evolved over tens of millions of years, producing complex societies with industrial-scale farming analogous to that of humans. Here we document reciprocal shifts in the genomes and transcriptomes of seven fungus-farming ant species and their fungal...

  12. Expanding Distribution of Lethal Amphibian Fungus Batrachochytrium salamandrivorans in Europe.

    Science.gov (United States)

    Spitzen-van der Sluijs, Annemarieke; Martel, An; Asselberghs, Johan; Bales, Emma K; Beukema, Wouter; Bletz, Molly C; Dalbeck, Lutz; Goverse, Edo; Kerres, Alexander; Kinet, Thierry; Kirst, Kai; Laudelout, Arnaud; Marin da Fonte, Luis F; Nöllert, Andreas; Ohlhoff, Dagmar; Sabino-Pinto, Joana; Schmidt, Benedikt R; Speybroeck, Jeroen; Spikmans, Frank; Steinfartz, Sebastian; Veith, Michael; Vences, Miguel; Wagner, Norman; Pasmans, Frank; Lötters, Stefan

    2016-07-01

    Emerging fungal diseases can drive amphibian species to local extinction. During 2010-2016, we examined 1,921 urodeles in 3 European countries. Presence of the chytrid fungus Batrachochytrium salamandrivorans at new locations and in urodeles of different species expands the known geographic and host range of the fungus and underpins its imminent threat to biodiversity.

  13. Reciprocal genomic evolution in the ant-fungus agricultural symbiosis

    DEFF Research Database (Denmark)

    Nygaard, Sanne; Hu, Haofu; Li, Cai;

    2016-01-01

    The attine ant-fungus agricultural symbiosis evolved over tens of millions of years, producing complex societies with industrial-scale farming analogous to that of humans. Here we document reciprocal shifts in the genomes and transcriptomes of seven fungus-farming ant species and their fungal...

  14. Fungus-associated bacteriome in charge of their host behaviour

    NARCIS (Netherlands)

    Schulz-Bohm, Kristin; Tyc, Olaf; Boer, Wietse de; Peereboom, Nils; Debets, Fons; Zaagman, Niels; Janssens, Thierry K.S.; Garbeva, Paolina

    2016-01-01

    Abstract Bacterial-fungal interactions are widespread in nature and there is a growing number of studies reporting distinct fungus-associated bacteria. However, little is known so far about how shifts in the fungus-associated bacteriome will affect the fungal host’s lifestyle. In the present study,

  15. Fungus-associated bacteriome in charge of their host behavior

    NARCIS (Netherlands)

    Schulz-Bohm, Kristin; Tyc, Olaf; Boer, de Wietse; Peereboom, Nils; Debets, Fons; Zaagman, Niels; Janssens, Thierry K.S.; Garbeva, Paolina

    2016-01-01

    Bacterial-fungal interactions are widespread in nature and there is a growing number of studies reporting distinct fungus-associated bacteria. However, little is known so far about how shifts in the fungus-associated bacteriome will affect the fungal host’s lifestyle. In the present study, we descri

  16. Comparative studies of the secretome of fungus-growing ants

    DEFF Research Database (Denmark)

    Linde, Tore; Grell, Morten Nedergaard; Schiøtt, Morten

    2009-01-01

    Leafcutter ants of the species Acromyrmex echinatior live in symbiosis with the fungus Leucoagaricus gongylophorus. The ants harvest fragments of leaves and carry them to the nest where they place the material on the fungal colony. The fungus secretes a wide array of proteins to degrade the leave...

  17. Medical image of the week: fungus ball

    Directory of Open Access Journals (Sweden)

    Rosen S

    2015-04-01

    Full Text Available No abstract available. Article truncated at 150 words. A 69 year-old Asian woman living in Arizona with a past medical history of nephrotic syndrome on high-dose steroids had worsening pulmonary symptoms. A computed tomography (CT of the chest (Figure 1 showed a 4.7 cm thin walled cavitary lesion in the right middle lobe compatible with mycetoma. She underwent thoracotomy for mycetoma resection. Surgical pathology confirmed an epithelial-lined cavity containing dense mycelia (Figure 2. Given the patient lived in an endemic area; the cavity was thought to be likely due to coccidioidomycosis. However, the mycetoma was of unclear etiology. No spherules were noted on GMS stain and tissue culture was negative. While of unclear clinical significance which fungus colonizes a pre-existing cavity, a Coccidioides PCR was performed and no Coccidioides genes were amplified making a Coccidioides mycetoma very unlikely. Pulmonary mycetoma or “fungus ball” consists of dense fungal elements and amorphous cellular material within a pre-existing pulmonary cavity. Classically ...

  18. Antimicrobial chemical constituents from endophytic fungus Phomasp.

    Institute of Scientific and Technical Information of China (English)

    Hidayat Hussain; Siegfried Draeger; Barbara Schulz; Karsten Krohn; Ines Kock; Ahmed Al-Harrasi; Ahmed Al-Rawahi; Ghulam Abbas; Ivan R Green; Afzal Shah; Amin Badshah; Muhammad Saleem

    2014-01-01

    Objective:To evaluate the antimicrobial potential of different extracts of the endophytic fungus Phomasp. and the tentative identification of their active constituents.Methods:The extract and compounds were screened for antimicrobial activity using theAgarWellDiffusionMethod. Four compounds were purified using column chromatography and their structures were assigned using1H and13CNMR spectra,DEPT,2DCOSY,HMQC andHMBC experiments.Results:The ethyl acetate fraction ofPhomasp. showed good antifungal, antibacterial, and algicidal properties.One new dihydrofuran derivative, named phomafuranol(1), together with three known compounds, phomalacton(2),(3R)-5-hydroxymellein(3) and emodin(4) were isolated from the ethyl acetate fraction ofPhomasp.Preliminary studies indicated that phomalacton(2) displayed strong antibacterial, good antifungal and antialgal activities.Similarly(3R)-5-hydroxymellein (3) and emodin(4) showed good antifungal, antibacterial and algicidal properties.Conclusions:Antimicrobial activities of the ethyl acetate fraction of the endophytic fungusPhomasp. and isolated compounds clearly demonstrate thatPhomasp. and its active compounds represent a great potential for the food, cosmetic and pharmaceutical industries.

  19. Ribonucleic acids in different tea fungus beverages

    Directory of Open Access Journals (Sweden)

    Malbaša Radomir V.

    2003-01-01

    Full Text Available In human nutrition, nucleic acids have to be balanced and limited up to 2 g/day because purines are degraded to urate, and excessive production of urate is a cause of gout which primarily affects adult males. Tea fungus beverage is a well known drink with high nutritional value and certain curative effects. Its benefits have been proved in a number of studies but it is still necessary to examine some potential harmful effects of this beverage. The aim of this paper was to investigate content of ribonucleic acids (RNA produced during tea fungus fermentation on a usual substrate sweetened black tea, and on Jerusalem artichoke tubers (J.A.T extract using method by Munro and Fleck (1966. pH, ribonucleic acids and also the production of proteins that affect purity of nucleic acids preparations were monitored. A higher value of RNA has been noticed in J.A.T. beverage (0.57 mg/ml and with observation of usual daily dose of the beverage it is completely safe and useful one.

  20. Assembly of complex plant–fungus networks

    Science.gov (United States)

    Toju, Hirokazu; Guimarães, Paulo R.; Olesen, Jens M.; Thompson, John N.

    2014-01-01

    Species in ecological communities build complex webs of interaction. Although revealing the architecture of these networks is fundamental to understanding ecological and evolutionary dynamics in nature, it has been difficult to characterize the structure of most species-rich ecological systems. By overcoming this limitation through next-generation sequencing technology, we herein uncover the network architecture of below-ground plant–fungus symbioses, which are ubiquitous to terrestrial ecosystems. The examined symbiotic network of a temperate forest in Japan includes 33 plant species and 387 functionally and phylogenetically diverse fungal taxa, and the overall network architecture differs fundamentally from that of other ecological networks. In contrast to results for other ecological networks and theoretical predictions for symbiotic networks, the plant–fungus network shows moderate or relatively low levels of interaction specialization and modularity and an unusual pattern of ‘nested’ network architecture. These results suggest that species-rich ecological networks are more architecturally diverse than previously recognized. PMID:25327887

  1. New Development Trend of Edible Fungus Industry in China

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    We elaborate support system of edible fungus industry from outlook on ecological economic development, legislation and standardization of variety approval, multiple-function innovation platform of industrial development research, and perfect talent cultivation and education system. Besides, we analyze the development trend of edible fungus industry from competitive advantages, position and role in national food security, industrial development trend driven by internal demand, diversified industrial development model, division of labor within the industry, and expansion of industrial chain. Then, from the point of zoning and planning of edible fungus industry, we put forward suggestions that it should start from modern industrial system and take the industrial cluster development and optimization as guidance. In addition, we present technical innovation direction of industrial development. It is proposed to strengthen propaganda, build industrial cultural atmosphere, and expand social cognition degree of edible fungus industry to promote its redevelopment. Finally, it is expected to promote international influence of edible fungus industry through experts appealing for policy support.

  2. Chemical composition of metapleural gland secretions of fungus-growing and non-fungus-growing ants.

    Science.gov (United States)

    Vieira, Alexsandro S; Morgan, E David; Drijfhout, Falko P; Camargo-Mathias, Maria I

    2012-10-01

    The metapleural gland is exclusive to ants, and unusual among exocrine glands in having no mechanism for closure and retention of secretion. As yet, no clear conclusion has been reached as to the function of metapleural gland secretion. Metapleural gland secretions were investigated for fungus-growing ants representing the derived attines Trachymyrmex fuscus, Atta laevigata, and Acromyrmex coronatus, the basal attines Apterostigma pilosum and Mycetarotes parallelus, and non-fungus-growing ants of the tribes Ectatommini (Ectatomma brunneum) and Myrmicini (Pogonomyrmex naegeli). Our results showed that the secretions of leaf-cutting ants (A. laevigata and A. coronatus) and the derived attine, T. fuscus, contain a greater variety and larger quantities of volatile compounds than those of myrmicine and ectatommine ants. The most abundant compounds found in the metapleural glands of A. laevigata and A. coronatus were hydroxyacids, and phenylacetic acid (only in A. laevigata). Indole was present in all groups examined, while skatole was found in large quantities only in attines. Ketones and aldehydes are present in the secretion of some attines. Esters are present in the metapleural gland secretion of all species examined, although mainly in A. laevigata, A. coronatus, and T. fuscus. Compared with basal attines and non-fungus-growing ants, the metapleural glands of leaf-cutting ants produce more acidic compounds that may have an antibiotic or antifungal function.

  3. Bioactive Triterpenes from the Fungus Piptoporus betulinus

    Directory of Open Access Journals (Sweden)

    Zeyad Alresly

    2016-01-01

    Full Text Available Phytochemical investigation of the ethyl acetate extract of the fruiting bodies from the basidiomycete Piptoporus betulinus led to the isolation of a new bioactive lanostane triterpene identified as 3 b -acetoxy-16-hydroxy-24-oxo-5α-lanosta-8- ene-21-oic acid (1. In addition, ten known triterpenes, polyporenic acid A (5, polyporenic acid C (4, three derivatives of polyporenic acid A (8, 10, 11, betulinic acid (3, betulin (2, ergosterol peroxide (6, 9,11-dehydroergosterol peroxide (7, and fomefficinic acid (9, were also isolated from the fungus. All isolated compounds were tested for antimicrobial activity against some Gram-positive and Gram-negative bacteria as well as against a fungal strain. The new triterpene and some of the other compounds showed antimicrobial activity against Gram-positive bacteria.

  4. SYSTEMIC INFECTION AND RELATED FUNGUS: AN OVERVIEW

    Directory of Open Access Journals (Sweden)

    Saha Rajsekhar

    2011-06-01

    Full Text Available A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds (British English: moulds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which are separate from plants, animals, and bacteria. One major difference is that fungal cells have cell walls that contain chitin, unlike the cell walls of plants, which contain cellulose. Many fungi play a crucial role in decomposition (breaking things down and returning nutrients to the soil. They are also used in medicine, an example is the antibiotic penicillin, as well as in industry and food preparation. In the present time the microbes are to be seen as disease causing organisms harming the mankind. The harm done by this community cannot be taken lightly as they are also useful in many ways. The above article is an effort to bring out the various fungal issued related to human.

  5. UTILIZACIÓN DE UNA NUEVA METODOLOGÍA PARA LA EVALUACIÓN DE ARROZ (Oryza sativa L. ANTE LA INFECCIÓN PRODUCIDA POR EL HONGO Pyricularia grisea

    Directory of Open Access Journals (Sweden)

    Regla M. Cárdenas

    2000-01-01

    Full Text Available Se evaluó la resistencia de varias líneas y varieda- des de arroz frente a la infección producida por el hongo Pyricularia grisea, agente causal de la enfermedad conocida como Piriculariosis de gran importancia a escala mundial. Se empleó una nueva metodología de campo utilizada por el Cen- tro Internacional de Agricultura Tropical (CIAT, la cual pro- pone realizar las evaluaciones en un sitio donde exista una alta diversidad genética del patógeno y una elevada presión del inóculo. El trabajo se desarrolló en la granja Caribe pertene- ciente al Complejo Agroindustrial Arrocero” Los Palacios” en Pinar del Río, donde la enfermedad es uno de los factores que limitan la producción. Los resultados mostraron un total de ocho líneas y variedades resistentes en la primera evaluación para el estado de plántula y siete en la segunda para ese mismo estado. Todos los materiales evaluados como resistentes en hoja para el estado de plántula resultaron ser susceptibles a la enfermedad en la panícula. No existió correlación entre las eva- luaciones realizadas en hojas y en la panícula.

  6. Assessment of the Effect of Fungicide and Seed Rate on the Incidence of Leaf Blast (Magnaphorthe Grisea, On the Growth of Foxtail Millet (Setaria Italica (L. P. BEAUV in North-eastern Nigeria

    Directory of Open Access Journals (Sweden)

    Z. G. S. Turaki

    2014-02-01

    Full Text Available In 2007 a multilocational trial was conducted in a split-plot using randomized complete block University of Maiduguri and Gashua Farm station to assess the effects of fungicide and seed rate on the incidence of leaf blast (Magnaphorte grisea, on the growth and yield of foxtail millet in the Northeastern Nigeria. The results showed that the lowest disease incidence of 20.8% and 0.4% were recorded from 100% recorded significantly (P < 0.05 the highest disease incidence of 80.0% and 64.3% at Maiduguri and Gashua respectively. The highest plant height and panicle length were recorded from plants grown at fungicide seed treatment ranging from 80-100% at seed rate of 5.0kg/ha. The lowest plant height and panicle length were obtained from plants grown from the untreated seed tate of 12.5kg/ha and while the lowest grain yields were recorded from untreated seed rate of 5.0kg/h at Maiduguri and Gashua respectively.

  7. Comparative studies of the secretome of fungus-growing ants

    DEFF Research Database (Denmark)

    Linde, Tore; Grell, Morten Nedergaard; Schiøtt, Morten

    2009-01-01

    Leafcutter ants of the species Acromyrmex echinatior live in symbiosis with the fungus Leucoagaricus gongylophorus. The ants harvest fragments of leaves and carry them to the nest where they place the material on the fungal colony. The fungus secretes a wide array of proteins to degrade the leaves...... into nutrients that the ants can feed on. The focus of this study is to discover, characterize and compare the secreted proteins. In order to do so cDNA libraries are constructed from mRNA extracted from the fungus material. The most efficient technology to screen cDNA libraries selectively for secreted...

  8. Specificity in the interaction between an epibiotic clavicipitalean fungus and its convolvulaceous host in a fungus/plant symbiotum

    Science.gov (United States)

    Steiner, Ulrike; Hellwig, Sabine

    2008-01-01

    Ipomoea asarifolia and Turbina corymbosa (Convolvulaceae) are associated with epibiotic clavicipitalean fungi responsible for the presence of ergoline alkaloids in these plants. Experimentally generated plants devoid of these fungi were inoculated with different epibiotic and endophytic fungi resulting in a necrotic or commensal situation. A symbiotum of host plant and its respective fungus was best established by integration of the fungus into the morphological differentiation of the host plant. This led us to suppose that secretory glands on the leaf surface of the host plant may play an essential role in ergoline alkaloid biosynthesis which takes place in the epibiotic fungus. PMID:19704834

  9. Effect of the Extract of Endophytic fungus, Nigrospora sphaerica CL ...

    African Journals Online (AJOL)

    : The ... After 12 h treatment, interaction of extract with MRSA cells resulted in the formation of pit ... Keywords: Endophytic fungus, Nigrospora sphaerica, Antimicrobial activity, Cellular structure ... human population, veterinary and aquaculture.

  10. An insect parasitoid carrying an ochratoxin producing fungus

    Science.gov (United States)

    Vega, Fernando E.; Posada, Francisco; Gianfagna, Thomas J.; Chaves, Fabio C.; Peterson, Stephen W.

    2006-06-01

    The insect parasitoid Prorops nasuta has been introduced from Africa to many coffee-producing countries in an attempt to control the coffee berry borer. In this paper, we report on the sequencing of the ITS LSU-rDNA and beta-tubulin loci used to identify a fungus isolated from the cuticle of a P. nasuta that emerged from coffee berries infected with the coffee berry borer. The sequences were compared with deposits in GenBank and the fungus was identified as Aspergillus westerdijkiae. The fungus tested positive for ochratoxin A production, with varying levels depending on the media in which it was grown. These results raise the possibility that an insect parasitoid might be disseminating an ochratoxin-producing fungus in coffee plantations.

  11. Evolutionary patterns of proteinase activity in attine ant fungus gardens

    DEFF Research Database (Denmark)

    Semenova, Tatyana; Hughes, David Peter; Boomsma, Jacobus Jan;

    2011-01-01

    hypothesized that fungal proteinase activity may have been under selection for efficiency and that different classes of proteinases might be involved. Results: We determined proteinase activity profiles across a wide pH range for fungus gardens of 14 Panamanian species of fungus-growing ants, representing...... activities than the lower attine symbionts. Their total in vitro proteinase activity peaked at pH values around 5, which is close to the pH that the ants maintain in their fungus gardens, suggesting that the pH optimum of fungal proteinases may have changed after the irreversible domestication...... of evolutionary more derived fungal symbionts. This notion is also supported by buffering capacities of fungus gardens at pH 5.2 being remarkably high, and suggests that the fungal symbiont actively helps to maintain garden acidity at this specific level. Metalloproteinases dominated the activity profiles...

  12. The role of mites in insect-fungus associations.

    Science.gov (United States)

    Hofstetter, R W; Moser, J C

    2014-01-01

    The interactions among insects, mites, and fungi are diverse and complex but poorly understood in most cases. Associations among insects, mites, and fungi span an almost incomprehensible array of ecological interactions and evolutionary histories. Insects and mites often share habitats and resources and thus interact within communities. Many mites and insects rely on fungi for nutrients, and fungi benefit from them with regard to spore dispersal, habitat provision, or nutrient resources. Mites have important impacts on community dynamics, ecosystem processes, and biodiversity within many insect-fungus systems. Given that mites are understudied but highly abundant, they likely have bigger, more important, and more widespread impacts on communities than previously recognized. We describe mutualistic and antagonistic effects of mites on insect-fungus associations, explore the processes that underpin ecological and evolutionary patterns of these multipartite communities, review well-researched examples of the effects of mites on insect-fungus associations, and discuss approaches for studying mites within insect-fungus communities.

  13. Antifungal Activity of Eucalyptus Oil against Rice Blast Fungi and the Possible Mechanism of Gene Expression Pattern

    Directory of Open Access Journals (Sweden)

    Li-Jun Zhou

    2016-05-01

    Full Text Available Eucalyptus oil possesses a wide spectrum of biological activity, including anti-microbial, fungicidal, herbicidal, acaricidal and nematicidal properties. We studied anti-fungal activities of the leaf oil extracted from Eucalyptus. grandis × E. urophylla. Eleven plant pathogenic fungi were tested based on the mycelium growth rates with negative control. The results showed that Eucalyptus oil has broad-spectrum inhibitory effects toward these fungi. Remarkable morphological and structural alterations of hypha have been observed for Magnaporthe grisea after the treatment. The mRNA genome array of M. grisea was used to detect genes that were differentially expressed in the test strains treated by the Eucalyptus oil than the normal strains. The results showed 1919 genes were significantly affected, among which 1109 were down-regulated and 810 were up-regulated (p < 0.05, absolute fold change >2. According to gene ontology annotation analysis, these differentially expressed genes may cause abnormal structures and physiological function disorders, which may reduce the fungus growth. These results show the oil has potential for use in the biological control of plant disease as a green biopesticide.

  14. Contributions to the study of Pseudopeziza trifolii (Bernh. Fuck. fungus

    Directory of Open Access Journals (Sweden)

    Olga PALL

    1966-08-01

    Full Text Available The present paper communicates the results of the laboratory experiments concerning the behaviour of the Pseudopeziza trifolii (Bernh. Fuck. fungus that produces the clover brown leaf spot, in different culture mediums. The mycelium of the fungus develops at its best on the peptone-glucose-agar medium. The appearance of pycnides of Sporonema phacidioides Desm. type in vitro, has been reported for the fourth time in Romania especially developing on the potatoe-dextrosis-agar and plum-agar mediums.

  15. Survey reveals the situation of Chinese caterpillar fungus resources

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Following its investigation of aweto (or Chinese caterpillar fungus) resources carried out from May to July 2007 on the Tibetan(or Qinghai-Tibet) Plateau,the central producing area of this precious ingredient for traditional Chinese medicine (TCM),the Xishuangbanna Tropical Botanical Garden (XTBG)under CAS conducted a further survey from May to July 2008 in the marginal habitats of this fungus.

  16. Biological control of Ascaris suum eggs by Pochonia chlamydosporia fungus.

    Science.gov (United States)

    Ferreira, Sebastião Rodrigo; de Araújo, Jackson Victor; Braga, Fábio Ribeiro; Araujo, Juliana Milani; Frassy, Luiza Neme; Ferreira, Aloízio Soares

    2011-12-01

    Ascaris suum is a gastrointestinal nematode parasite of swines. The aim of this study was to observe Pochonia chlamydosporia fungus on biological control of A. suum eggs after fungus passage through swines gastrointestinal tract. Eighteen pigs, previously dewormed, were randomly divided into three groups: group 1, treated with the fungus isolate VC4; group 2, treated with the fungus isolate VC1 and group 3 did not receive fungus (control). In the treated groups, each animal received a 9 g single dose of mycelium mass containing P. chlamydosporia (VC1 or VC4). Thereafter, animal fecal samples were collected at the following intervals: 8, 12, 24, 36, 48, 72 and 96 h after treatment beginning and these were poured in Petri dishes containing 2% water-agar culture medium. Then, 1,000 A. suum eggs were poured into each dish and kept in an incubator at 26 °C and in the dark for 30 days. After this period, approximately 100 eggs were removed from each Petri dish and morphologically analyzed under light microscopy following the ovicidal activity parameters. The higher percentage observed for isolated VC4 eggs destruction was 57.5% (36 h) after fungus administration and for isolate VC1 this percentage was 45.8% (24 h and 72 h) (p > 0.01). P. chlamydosporia remained viable after passing through the gastrointestinal tract of swines, maintaining its ability of destroying A. suum eggs.

  17. Solubilization of diabase and phonolite dust by filamentous fungus

    Directory of Open Access Journals (Sweden)

    Juliana Andréia Vrba Brandão

    2014-10-01

    Full Text Available The objective of this study was to evaluate the effect of the fungus Aspergillus niger strain CCT4355 in the release of nutrients contained in two types of rock powder (diabase and phonolite by means of in vitro solubilization trials. The experimental design was completely randomized in a 5 x 4 factorial design with three replications. It was evaluated five treatments (phonolite dust + culture medium; phonolite dust + fungus + culture medium; diabase powder + culture medium; diabase powder + fungus + culture medium and fungus + culture medium and four sampling dates (0, 10, 20 and 30 days. Rock dust (0.4% w/v was added to 125 mL Erlenmeyer flasks containing 50 mL of liquid culture medium adapted to A. niger. The flasks were incubated at 30°C for 30 days, and analysis of pH (in water, titratable acidity, and concentrations of soluble potassium, calcium, magnesium, zinc, iron and manganese were made. The fungus A. niger was able to produce organic acids that solubilized ions. This result indicates its potential to alter minerals contained in rock dust, with the ability to interact in different ways with the nutrients. A significant increase in the amount of K was found in the treatment with phonolite dust in the presence of the fungus. The strain CCT4355 of A. niger can solubilize minerals contained in these rocks dust.

  18. 'PACLIMS': a component LIM system for high-throughput functional genomic analysis.

    Science.gov (United States)

    Donofrio, Nicole; Rajagopalon, Ravi; Brown, Douglas; Diener, Stephen; Windham, Donald; Nolin, Shelly; Floyd, Anna; Mitchell, Thomas; Galadima, Natalia; Tucker, Sara; Orbach, Marc J; Patel, Gayatri; Farman, Mark; Pampanwar, Vishal; Soderlund, Cari; Lee, Yong-Hwan; Dean, Ralph A

    2005-04-12

    Recent advances in sequencing techniques leading to cost reduction have resulted in the generation of a growing number of sequenced eukaryotic genomes. Computational tools greatly assist in defining open reading frames and assigning tentative annotations. However, gene functions cannot be asserted without biological support through, among other things, mutational analysis. In taking a genome-wide approach to functionally annotate an entire organism, in this application the approximately 11,000 predicted genes in the rice blast fungus (Magnaporthe grisea), an effective platform for tracking and storing both the biological materials created and the data produced across several participating institutions was required. The platform designed, named PACLIMS, was built to support our high throughput pipeline for generating 50,000 random insertion mutants of Magnaporthe grisea. To be a useful tool for materials and data tracking and storage, PACLIMS was designed to be simple to use, modifiable to accommodate refinement of research protocols, and cost-efficient. Data entry into PACLIMS was simplified through the use of barcodes and scanners, thus reducing the potential human error, time constraints, and labor. This platform was designed in concert with our experimental protocol so that it leads the researchers through each step of the process from mutant generation through phenotypic assays, thus ensuring that every mutant produced is handled in an identical manner and all necessary data is captured. Many sequenced eukaryotes have reached the point where computational analyses are no longer sufficient and require biological support for their predicted genes. Consequently, there is an increasing need for platforms that support high throughput genome-wide mutational analyses. While PACLIMS was designed specifically for this project, the source and ideas present in its implementation can be used as a model for other high throughput mutational endeavors.

  19. 'PACLIMS': A component LIM system for high-throughput functional genomic analysis

    Directory of Open Access Journals (Sweden)

    Farman Mark

    2005-04-01

    Full Text Available Abstract Background Recent advances in sequencing techniques leading to cost reduction have resulted in the generation of a growing number of sequenced eukaryotic genomes. Computational tools greatly assist in defining open reading frames and assigning tentative annotations. However, gene functions cannot be asserted without biological support through, among other things, mutational analysis. In taking a genome-wide approach to functionally annotate an entire organism, in this application the ~11,000 predicted genes in the rice blast fungus (Magnaporthe grisea, an effective platform for tracking and storing both the biological materials created and the data produced across several participating institutions was required. Results The platform designed, named PACLIMS, was built to support our high throughput pipeline for generating 50,000 random insertion mutants of Magnaporthe grisea. To be a useful tool for materials and data tracking and storage, PACLIMS was designed to be simple to use, modifiable to accommodate refinement of research protocols, and cost-efficient. Data entry into PACLIMS was simplified through the use of barcodes and scanners, thus reducing the potential human error, time constraints, and labor. This platform was designed in concert with our experimental protocol so that it leads the researchers through each step of the process from mutant generation through phenotypic assays, thus ensuring that every mutant produced is handled in an identical manner and all necessary data is captured. Conclusion Many sequenced eukaryotes have reached the point where computational analyses are no longer sufficient and require biological support for their predicted genes. Consequently, there is an increasing need for platforms that support high throughput genome-wide mutational analyses. While PACLIMS was designed specifically for this project, the source and ideas present in its implementation can be used as a model for other high throughput

  20. Candicidin-producing Streptomyces support leaf-cutting ants to protect their fungus garden against the pathogenic fungus Escovopsis

    OpenAIRE

    Haeder, Susanne; Wirth, Rainer; Herz, Hubert; Spiteller, Dieter

    2009-01-01

    Leaf-cutting ants such as Acromyrmex octospinosus live in obligate symbiosis with fungi of the genus Leucoagaricus, which they grow with harvested leaf material. The symbiotic fungi, in turn, serve as a major food source for the ants. This mutualistic relation is disturbed by the specialized pathogenic fungus Escovopsis sp., which can overcome Leucoagaricus sp. and thus destroy the ant colony. Microbial symbionts of leaf-cutting ants have been suggested to protect the fungus garden against Es...

  1. Overexpression of MoSM1, encoding for an immunity-inducing protein from Magnaporthe oryzae, in rice confers broad-spectrum resistance against fungal and bacterial diseases

    Science.gov (United States)

    Hong, Yongbo; Yang, Yayun; Zhang, Huijuan; Huang, Lei; Li, Dayong; Song, Fengming

    2017-01-01

    Potential of MoSM1, encoding for a cerato-platanin protein from Magnaporthe oryzae, in improvement of rice disease resistance was examined. Transient expression of MoSM1 in rice leaves initiated hypersensitive response and upregulated expression of defense genes. When transiently expressed in tobacco leaves, MoSM1 targeted to plasma membrane. The MoSM1-overexpressing (MoSM1-OE) transgenic rice lines showed an improved resistance, as revealed by the reduced disease severity and decreased in planta pathogen growth, against 2 strains belonging to two different races of M. oryzae, causing blast disease, and against 2 strains of Xanthomonas oryzae pv. oryzae, causing bacterial leaf blight disease. However, no alteration in resistance to sheath blight disease was observed in MoSM1-OE lines. The MoSM1-OE plants contained elevated levels of salicylic acid (SA) and jasmonic acid (JA) and constitutively activated the expression of SA and JA signaling-related regulatory and defense genes. Furthermore, the MoSM1-OE plants had no effect on drought and salt stress tolerance and on grain yield. We conclude that MoSM1 confers a broad-spectrum resistance against different pathogens through modulating SA- and JA-mediated signaling pathways without any penalty on abiotic stress tolerance and grain yield, providing a promising potential for application of MoSM1 in improvement of disease resistance in crops. PMID:28106116

  2. Analysis of Magnaporthe oryzae genome reveals a fungal effector, which is able to induce resistance response in transgenic rice line containing resistance gene, Pi54

    Directory of Open Access Journals (Sweden)

    Soham Ray

    2016-08-01

    Full Text Available Rice blast caused by Magnaporthe oryzae is one of the most important diseases of rice. Pi54, a rice gene that imparts resistance to M. oryzae isolates prevalent in India, was already cloned but its avirulent counterpart in the pathogen was not known.. After decoding the whole genome of an avirulent isolate of M. oryzae, we predicted 11440 protein coding genes and then identified four candidate effector proteins which are exclusively expressed in the infectious structure, appresoria. In silico protein modeling followed by interaction analysis between Pi54 protein model and selected four candidate effector proteins models revealed that Mo-01947_9 protein model encoded by a gene located at chromosome 4 of M. oryzae, interacted best at the Leucine Rich Repeat domain of Pi54 protein model. Yeast-two-hybrid analysis showed that Mo-01947_9 protein physically interacts with Pi54 protein. Nicotiana benthamiana leaf infiltration assay confirmed induction of hypersensitive response in the presence of Pi54 gene in a heterologous system. Genetic complementation test also proved that Mo-01947_9 protein induces avirulence response in the pathogen in the presence of Pi54 gene. Here, we report identification and cloning of a new fungal effector gene which interacts with resistance gene Pi54 gene in rice.

  3. Comparison and Validation of Putative Pathogenicity-Related Genes Identified by T-DNA Insertional Mutagenesis and Microarray Expression Profiling in Magnaporthe oryzae

    Science.gov (United States)

    Wáng, Ying; Tan, Qi; Gao, Ying Nv; Li, Yan

    2017-01-01

    High-throughput technologies of functional genomics such as T-DNA insertional mutagenesis and microarray expression profiling have been employed to identify genes related to pathogenicity in Magnaporthe oryzae. However, validation of the functions of individual genes identified by these high-throughput approaches is laborious. In this study, we compared two published lists of genes putatively related to pathogenicity in M. oryzae identified by T-DNA insertional mutagenesis (comprising 1024 genes) and microarray expression profiling (comprising 236 genes), respectively, and then validated the functions of some overlapped genes between the two lists by knocking them out using the method of target gene replacement. Surprisingly, only 13 genes were overlapped between the two lists, and none of the four genes selected from the overlapped genes exhibited visible phenotypic changes on vegetative growth, asexual reproduction, and infection ability in their knockout mutants. Our results suggest that both of the lists might contain large proportions of unrelated genes to pathogenicity and therefore comparing the two gene lists is hardly helpful for the identification of genes that are more likely to be involved in pathogenicity as we initially expected.

  4. Dicty_cDB: SFB460 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available grisea protein kinase CHM1 (CHM1) gene, complete cds. 54 0.004 1 CD030975 |CD030975.1 mgmt004xF23f.b Mated c...ulture Magnaporthe grisea cDNA clone mgmt004xF23 5', mRNA sequence. 54 0.004 1 AC083826 |AC083826.7 Homo sap

  5. Isolated Polynucleotides and Methods of Promoting a Morphology in a Fungus

    Science.gov (United States)

    Lasure, Linda L [Fall City, WA; Dai, Ziyu [Richland, WA

    2008-10-21

    The invention includes isolated polynucleotide molecules that are differentially expressed in a native fungus exhibiting a first morphology relative to the native fungus exhibiting a second morphology. The invention includes a method of enhancing a bioprocess utilizing a fungus. A transformed fungus is produced by transforming a fungus with a recombinant polynucleotide molecule. The recombinant polynucleotide molecule contains an isolated polynucleotide sequence linked operably to a promoter. The polynucleotide sequence is expressed to promote a first morphology. The first morphology of the transformed fungus enhances a bioprocess relative to the bioprocess utilizing a second morphology.

  6. Allergens of the entomopathogenic fungus Beauveria bassiana

    Directory of Open Access Journals (Sweden)

    Keyhani Nemat O

    2005-01-01

    Full Text Available Abstract Background Beauveria bassiana is an important entomopathogenic fungus currently under development as a bio-control agent for a variety of insect pests. Although reported to be non-toxic to vertebrates, the potential allergenicity of Beauveria species has not been widely studied. Methods IgE-reactivity studies were performed using sera from patients displaying mould hypersensitivity by immunoblot and immunoblot inhibition. Skin reactivity to B. bassiana extracts was measured using intradermal skin testing. Results Immunoblots of fungal extracts with pooled as well as individual sera showed a distribution of IgE reactive proteins present in B. bassiana crude extracts. Proteinase K digestion of extracts resulted in loss of IgE reactive epitopes, whereas EndoH and PNGaseF (glycosidase treatments resulted in minor changes in IgE reactive banding patterns as determined by Western blots. Immunoblot inhibitions experiments showed complete loss of IgE-binding using self protein, and partial inhibition using extracts from common allergenic fungi including; Alternaria alternata, Aspergillus fumigatus, Cladosporium herbarum, Candida albicans, Epicoccum purpurascens, and Penicillium notatum. Several proteins including a strongly reactive band with an approximate molecular mass of 35 kDa was uninhibited by any of the tested extracts, and may represent B. bassiana specific allergens. Intradermal skin testing confirmed the in vitro results, demonstrating allergenic reactions in a number of individuals, including those who have had occupational exposure to B. bassiana. Conclusions Beauveria bassiana possesses numerous IgE reactive proteins, some of which are cross-reactive among allergens from other fungi. A strongly reactive potential B. bassiana specific allergen (35 kDa was identified. Intradermal skin testing confirmed the allergenic potential of B. bassiana.

  7. Dicty_cDB: SLK556 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available to Eukaryotic Initiation Factor 4A (EIF-4), mRNA sequence. 48 3e-07 2 CD033297 |CD033297.1 mgmt...012xE12f.b Mated culture Magnaporthe grisea cDNA clone mgmt012xE12 5', mRNA sequence. 48 4e-0...7 2 CD033621 |CD033621.1 mgmt013xG04f.b Mated culture Magnaporthe grisea cDNA clone mgmt013xG04 5', mRNA seq

  8. Potential for nitrogen fixation in fungus-growing termite symbioses

    Directory of Open Access Journals (Sweden)

    Panagiotis Sapountzis

    2016-12-01

    Full Text Available Termites host a gut microbiota of diverse and essential symbionts that enable specialization on dead plant material; an abundant, but nutritionally imbalanced food source. To supplement the severe shortage of dietary nitrogen (N, some termite species make use of diazotrophic bacteria to fix atmospheric nitrogen (N2. Fungus-growing termites (subfamily Macrotermitinae host a fungal exosymbiont (genus Termitomyces that provides digestive services and the main food source for the termites. This has been thought to obviate the need for N2-fixation by bacterial symbionts. Here we challenge this notion by performing acetylene reduction assays of live colony material to show that N2 fixation is present in two major genera (Macrotermes and Odontotermes of fungus-growing termites. We compare and discuss fixation rates in relation to those obtained from other termites, and suggest avenues of research that may lead to a better understanding of N2 fixation in fungus-growing and other termites.

  9. Evolutionary patterns of proteinase activity in attine ant fungus gardens

    DEFF Research Database (Denmark)

    Semenova, Tatyana; Hughes, David Peter; Boomsma, Jacobus Jan;

    2011-01-01

    hypothesized that fungal proteinase activity may have been under selection for efficiency and that different classes of proteinases might be involved. Results: We determined proteinase activity profiles across a wide pH range for fungus gardens of 14 Panamanian species of fungus-growing ants, representing...... eight genera. We mapped these activity profiles on an independently obtained molecular phylogeny of the symbionts and show that total proteinase activity in lower attine symbionts peaks at ca. pH 6. The higher attine symbionts that have no known free-living relatives had much higher proteinase...... activities than the lower attine symbionts. Their total in vitro proteinase activity peaked at pH values around 5, which is close to the pH that the ants maintain in their fungus gardens, suggesting that the pH optimum of fungal proteinases may have changed after the irreversible domestication...

  10. Rock Phosphate Solubilization Mechanisms of One Fungus and One Bacterium

    Institute of Scientific and Technical Information of China (English)

    LIN Qi-mei; ZHAO Xiao-rong; ZHAO Zi-juan; LI Bao-guo

    2002-01-01

    Many microorganisms can dissolve the insoluble phosphates like apatite. However, the mechanisms are still not clear. This study was an attempt to investigate the mechanisms of rock phosphate solubilization by an Aspergillus 2TCiF2 and an Arthrobacter1TCRi7. The results indicated that the fungus produced a large amount of organic acids, mainly oxalic acid. The total quantity of the organic acids produced by the fungus was 550 times higher than that by the bacterium. Different organic acids had completely different capacities to solubilize the rock. Oxalic acid and citric acid had stronger capacity to dissolve the rock than malic acid, tartaric acid, lactic acid, acetic acid, malonic acid and succinic acid. The fungus solubilized the rock through excreting both proton and organic acids. The rock solubilization of the bacterium depended on only proton.

  11. Isolation and identification of iron ore-solubilising fungus

    Directory of Open Access Journals (Sweden)

    Damase Khasa

    2010-09-01

    Full Text Available Potential mineral-solubilising fungi were successfully isolated from the surfaces of iron ore minerals. Four isolates were obtained and identified by molecular and phylogenetic methods as close relatives of three different genera, namely Penicillium (for isolate FO, Alternaria (for isolates SFC2 and KFC1 and Epicoccum (for isolate SFC2B. The use of tricalcium phosphate (Ca3(PO42in phosphate-solubilising experiments confirmed isolate FO as the only phosphate solubiliser among the isolated fungi. The bioleaching capabilities of both the fungus and its spent liquid medium were tested and compared using two types of iron ore materials, conglomerate and shale, from the Sishen Iron Ore Mine as sources of potassium (K and phosphorus (P. The spent liquid medium removed more K (a maximum of 32.94% removal, from conglomerate, than the fungus (a maximum of 21.36% removal, from shale. However, the fungus removed more P (a maximum of 58.33% removal, from conglomerate than the spent liquid medium (a maximum of 29.25% removal, from conglomerate. The results also indicated a potential relationship between the removal of K or P and the production of organic acids by the fungus. A high production of gluconic acid could be related to the ability of the fungus to reduce K and P. Acetic, citric and maleic acids were also produced by the fungus, but in lower quantities. In addition, particle size and iron ore type were also shown to have significant effects on the removal of potassium and phosphorus from the iron ore minerals. We therefore conclude that the spent liquid medium from the fungal isolate FO can potentially be used for biobeneficiation of iron ore minerals.

  12. Exploring the Potential for Actinobacteria as Defensive Symbionts in Fungus-Growing Termites

    NARCIS (Netherlands)

    Visser, A.A.; Mesquita Nobre, T.; Currie, C.R.; Aanen, D.K.; Poulsen, M.

    2012-01-01

    In fungus-growing termites, fungi of the subgenus Pseudoxylaria threaten colony health through substrate competition with the termite fungus (Termitomyces). The potential mechanisms with which termites suppress Pseudoxylaria have remained unknown. Here we explore if Actinobacteria potentially play a

  13. Exploring the Potential for Actinobacteria as Defensive Symbionts in Fungus-Growing Termites

    NARCIS (Netherlands)

    Visser, A.A.; Mesquita Nobre, T.; Currie, C.R.; Aanen, D.K.; Poulsen, M.

    2012-01-01

    In fungus-growing termites, fungi of the subgenus Pseudoxylaria threaten colony health through substrate competition with the termite fungus (Termitomyces). The potential mechanisms with which termites suppress Pseudoxylaria have remained unknown. Here we explore if Actinobacteria potentially play a

  14. Pseudoxylaria as stowaway of the fungus-growing termite nest:

    DEFF Research Database (Denmark)

    Visser, Anna A.; Kooij, Pepijn Wilhelmus; Debets, Alfons J. M.

    2011-01-01

    Though inconspicuous in healthy nests, Pseudoxylaria species are almost always present and overgrow deteriorating fungus-growing termite gardens. Whether these fungi are detrimental to the fungus-garden, benign, or even beneficial is unclear. We hypothesize that Pseudoxylaria is a stowaway...... that practices a sit-and-wait strategy to survive in the termite nest. Using isolates from three different termite genera to test our hypothesis, we compared Pseudoxylaria’s growth on 40 carbon sources with that of Termitomyces and tested its interaction with Termitomyces. The C-source use of both fungi largely...

  15. Induced systemic resistance responses in perennial ryegrass against Magnaporthe oryzae elicited by semi-purified surfactin lipopeptides and live cells of Bacillus amyloliquefaciens.

    Science.gov (United States)

    Rahman, Alamgir; Uddin, Wakar; Wenner, Nancy G

    2015-08-01

    The suppressive ability of several strains of cyclic lipopeptide-producing Bacillus rhizobacteria to grey leaf spot disease caused by Magnaporthe oryzae has been documented previously; however, the underlying mechanism(s) involved in the induced systemic resistance (ISR) activity in perennial ryegrass (Lolium perenne L.) remains unknown. Root-drench application of solid-phase extraction (SPE)-enriched surfactin and live cells of mutant Bacillus amyloliquefaciens strain FZB42-AK3 (produces surfactin, but not bacillomycin D and fengycin) significantly reduced disease incidence and severity on perennial ryegrass. The application of the treatments revealed a pronounced multilayered ISR defence response activation via timely and enhanced accumulation of hydrogen peroxide (H2O2), elevated cell wall/apoplastic peroxidase activity, and deposition of callose and phenolic/polyphenolic compounds underneath the fungal appressoria in naïve leaves, which was significantly more intense in treated plants than in mock-treated controls. Moreover, a hypersensitive response (HR)-type reaction and enhanced expression of LpPrx (Prx, peroxidase), LpOXO4 (OXO, oxalate oxidase), LpPAL (PAL, phenylalanine ammonia lyase), LpLOXa (LOX, lipoxygenase), LpTHb (putative defensin) and LpDEFa (DEFa, putative defensin) in perennial ryegrass were associated with SPE-enriched surfactin and live AK3 cell treatments, acting as a second layer of defence when pre-invasive defence responses failed. The results indicate that ISR activity following surfactin perception may sensitize H2O2 -mediated defence responses, thereby providing perennial ryegrass with enhanced protection against M. oryzae.

  16. Genetic and physical mapping of AvrPi7, a novel avirulence gene of Magnaporthe oryzae using physical position-ready markers

    Institute of Scientific and Technical Information of China (English)

    FENG ShuJie; WANG Ling; MA JunHong; LIN Fei; PAN QingHua

    2007-01-01

    Rice blast, caused by the fungal pathogen Magnaporthe oryzae, is one of the most devastating crop diseases worldwide. The avirulence gene corresponding to rice blast resistance gene Pi7 in field isolate CHL346 was inherited as a single gene, designated AvrPi7, in a segregating population consisting of 189 ascospore progenies derived from a cross between field isolates CHL346 and CHL42. In order to determine the chromosomal location of the AvrPi7 locus, a total of 121 simple sequence repeat (SSR) markers were developed based on the whole-genome sequence of reference isolate 70-15 of M. oryzae.Linkage analysis of the locus with these SSR markers showed that eight SSR markers on chromosome1 were linked to the locus, among which the closest flanking markers MS1-9 and MS1-15 were 3.2 and 16.4 cM from the locus, respectively. For fine mapping, additional PCR-based makers including eight SSR markers and three candidate avirulence gene (CAG) markers were developed in the region flanking both markers. The AvrPi7 locus was genetically delimited within a 1.6-cM region flanked by markers MS1-21 and MS1-22, and co-segregated with the marker CAG2. To construct a physical map of the AvrPi7 locus, molecular markers linked to the Avr gene were mapped on the supercontigs of the reference isolate 70-15 through bioinformation analysis (BIA). Consequently, the AvrPi7 locus was delimited to a 75-kb interval flanked by markers MS1-21 and MS1-22 based on the reference sequence.Merodiploids observed in this study are also discussed.

  17. Endoplasmic reticulum membrane-bound MoSec62 is involved in the suppression of rice immunity and is essential for the pathogenicity of Magnaporthe oryzae.

    Science.gov (United States)

    Zhou, Zhuangzhi; Pang, Zhiqian; Li, Guihua; Lin, Chunhua; Wang, Jing; Lv, Qiming; He, Chaozu; Zhu, Lihuang

    2016-10-01

    Pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) constitutes the first line of plant inducible immunity. As an important step of plant colonization, phytopathogens have to suppress PTI, and secreted effectors are therefore co-evolved and deployed. In this study, we characterized the function of MoSec62 of Magnaporthe oryzae, the causal agent of the destructive rice blast. MoSec62 encodes a homologue of Sec62p, a yeast endoplasmic reticulum (ER) membrane transporter for precursors of secretory proteins. We showed that a T-DNA insertion into the promoter region of MoSec62, causing a disturbance to the up-regulation of MoSec62 expression during blast invasion, resulted in a complete loss of blast virulence of the mutant, M1575. Both 3,3'-diaminobenzidine (DAB) staining of the infected rice leaves and expression analysis revealed that the infectious attempt by the mutant led to strong defence responses of rice. Consistently, in transcriptomic analysis of rice leaves subject to blast inoculation, a battery of defence responses was found to be induced exclusively on M1575 challenge. For further exploration, we tested the pathogenicity on a highly susceptible rice variety and detected the accumulation of Slp1, a known PTI suppressor. Both results suggested that the mutant most likely failed to overcome rice PTI. In addition, we showed that MoSec62 was able to rescue the thermosensitivity of a yeast Δsec62, and the MoSec62-GFP fusion was co-localized to the ER membrane, both suggesting the conservation of Sec62 homologues. In conclusion, our data indicate that MoSec62, probably as an ER membrane transporter, plays an essential role in antagonizing rice defence at the early stages of blast invasion.

  18. Disruption and molecular characterization of calpains-related (MoCAPN1, MoCAPN3 and MoCAPN4) genes in Magnaporthe oryzae.

    Science.gov (United States)

    Khan, Irshad Ali; Wang, Yao; Li, Hai-Jiao; Lu, Jian-Ping; Liu, Xiao-Hong; Lin, Fu-Cheng

    2014-11-01

    Calpains are intracellular, cysteine proteases found in plants, animals and fungi functioning as signal transduction components in different cellular pathways including sporulation and alkaline adaptation in fungi. Calpains-related MoCAPN1 (MGG_14872), MoCAPN3 (MGG_15810) and MoCAPN4 (MGG_04818) genes from Magnaporthe oryzae genome which are 2604, 3513 and 771-bp in length and encoding identical proteins of 867, 1170 and 256 amino acids were functionally characterized for different phenotypes through gene disruption method. All the mutants except those for MoCAPN1 showed normal phenotypes. In pathogenicity test, the mutants did not lead to any visible changes in phenotypes causing similar blast lesions on blast susceptible rice and barley leaves as those of the Guy-11 strain suggesting no major role in pathogenicity. Germ tubes formation, appressorium formation, mycelium radial growth and mating with 2539 strain were indistinguishable among the mutants and Guy-11 strains. Cell wall integrity (congo red) test, stress response under chemical pressure (ZnSO4, CuSO4 and CdCl2), osmotic and oxidative (NaCl and H2O2) stress response, growth response on glucose and nitrogen deficient media resulted in similar results in the mutants and Guy-11 strains. However, mutants for ΔMoCAPN1 gene produced reduced (0.57±0.15B and 0.54±0.05B) conidia compared to that (1.69±0.13A) of the Guy-11 strain showing its involvement in conidiation.

  19. Fluorescent co-localization of PTS1 and PTS2 and its application in analysis of the gene function and the peroxisomal dynamic in Magnaporthe oryzae

    Institute of Scientific and Technical Information of China (English)

    Jiao-yu WANG; Fu-cheng LIN; Guo-chang SUN; Xiao-yan WU; Zhen ZHANG; Xin-fa DU; Rong-yao CHAI; Xiao-hong LIU; Xue-qin MAO; Hai-ping QIU; Yan-li WANG

    2008-01-01

    The peroxisomal matrix proteins involved in many important biological metabolism pathways in eukaryotic cells are encoded by nucleal genes, synthesized in the cytoplasm and then transported into the organelles. Targeting and import of these proteins depend on their two peroxisomal targeting signals (PTS1 and PTS2) in sequence as we have known so far. The vectors of the fluorescent fusions with PTS, i.e., green fluorescence protein (GFP)-PTSI, GFP-PTS2 and red fluorescence protein (RFP)-PTS1, were constructed and introduced into Magnaporthe oryzae Guy11 cells. Transformants containing these fusions emitted fluorescence in a punctate pattern, and the locations of the red and green fluorescence overlapped exactly in RFP-PTS1 and GFP-PTS2 co-transformed strains. These data indicated that both PTS 1 and PTS2 fusions were imported into peroxisomes. A probable higher efficiency of PTSI machinery was revealed by comparing the fluorescence backgrounds in GFP-PTS1 and GFP-PTS2 transformants. By introducing both RFP-PTS1 and GFP-PTS2 into △mgpex6 mutants, the involvement of MGPEX6 gene in both PTS1 and PTS2 pathways was proved. In addition, using these transformants, the inducement of peroxisomes and the dynamic of peroxisomal number during the pre-penetration processes were investigated as well. In summary, by the localization and co-localization of PTSI and PTS2, we provided a useful tool to evaluate the biological roles of the peroxisomes and the related genes.

  20. [Study of water-soluble compounds from fungus garden of Odontotermes formosanus].

    Science.gov (United States)

    Xue, Dejun; Zhou, Hui; Zhang, Min; Xie, Kang; Zhang, Yong

    2005-10-01

    To study water-soluble compounds from fungus garden of Odontotermes formosanus. The chemical constituents of fungus garden were analyzed and identified by GC-MS. 28 compounds were separated and 11 chemical constituents were identified. The main constituents in water-solubles from fungus garden of Odontotermes formosanus are palmitic acid, linolei acid and oleic aid.

  1. Current Situations of Edible Fungus Production in Lianyungang City and Development Countermeasures

    Institute of Scientific and Technical Information of China (English)

    LI Guan-xi; GE Xiong-can; WEI Liang-zhi

    2012-01-01

    On the basis of characteristics of edible fungus production in Lianyungang City, we analyzed its advantages and disadvantages and put forward suggestions and countermeasures for development of edible fungus industry, mainly including strengthening guidance and leadership of government, introducing professional personnel, and developing the edible fungus industry through science and technology.

  2. The genome sequence of the model ascomycete fungus Podospora anserina

    NARCIS (Netherlands)

    Espagne, Eric; Lespinet, Olivier; Malagnac, Fabienne; Da Silva, Corinne; Jaillon, Olivier; Porcel, Betina M; Couloux, Arnaud; Aury, Jean-Marc; Ségurens, Béatrice; Poulain, Julie; Anthouard, Véronique; Grossetete, Sandrine; Khalili, Hamid; Coppin, Evelyne; Déquard-Chablat, Michelle; Picard, Marguerite; Contamine, Véronique; Arnaise, Sylvie; Bourdais, Anne; Berteaux-Lecellier, Véronique; Gautheret, Daniel; de Vries, Ronald P; Battaglia, Evy; Coutinho, Pedro M; Danchin, Etienne Gj; Henrissat, Bernard; Khoury, Riyad El; Sainsard-Chanet, Annie; Boivin, Antoine; Pinan-Lucarré, Bérangère; Sellem, Carole H; Debuchy, Robert; Wincker, Patrick; Weissenbach, Jean; Silar, Philippe

    2008-01-01

    BACKGROUND: The dung-inhabiting ascomycete fungus Podospora anserina is a model used to study various aspects of eukaryotic and fungal biology, such as ageing, prions and sexual development. RESULTS: We present a 10X draft sequence of P. anserina genome, linked to the sequences of a large expressed

  3. Carbon starvation in the filamentous fungus Aspergillus niger

    NARCIS (Netherlands)

    Nitsche, Benjamin Manuel

    2012-01-01

    This study investigated carbon starvation in the filamentous fungus Aspergillus niger during submerged cultivation in bioreactor batch cultures. The work described in this thesis can be discussed as follows: (I) Establishment of computational resources for omics data analysis and interpretation in c

  4. Fungus-Growing Termites Originated in African Rain Forest

    DEFF Research Database (Denmark)

    Aanen, Duur Kornelis; Eggleton, Paul

    2005-01-01

    extant savanna species are found in most genera, this moreover suggests that the savanna has repeatedly been colonized by fungus-growing termites. Furthermore, at least four independent "out-of-Africa" migrations into Asia, and at least one independent migration to Madagascar, have occurred. Although...

  5. EVOLUTIONARY TRANSITIONS IN ENZYME ACTIVITY OF ANT FUNGUS GARDENS

    DEFF Research Database (Denmark)

    De Fine Licht, Henrik H; Schiøtt, Morten; Mueller, Ulrich G

    2010-01-01

    Fungus-growing (attine) ants and their fungal symbionts passed through several evolutionary transitions during their 50 million year old evolutionary history. The basal attine lineages often shifted between two main cultivar clades, whereas the derived higher-attine lineages maintained an associa......Fungus-growing (attine) ants and their fungal symbionts passed through several evolutionary transitions during their 50 million year old evolutionary history. The basal attine lineages often shifted between two main cultivar clades, whereas the derived higher-attine lineages maintained...... an association with a monophyletic clade of specialized symbionts. In conjunction with the transition to specialized symbionts, the ants advanced in colony size and social complexity. Here we provide a comparative study of the functional specialization in extracellular enzyme activities in fungus gardens across...... the attine phylogeny. We show that, relative to sister clades, gardens of higher-attine ants have enhanced activity of protein-digesting enzymes, whereas gardens of leaf-cutting ants also have increased activity of starch-digesting enzymes. However, the enzyme activities of lower-attine fungus gardens...

  6. Leucopaxillus lepistoides, a new steppe fungus in Poland

    Directory of Open Access Journals (Sweden)

    Janusz Łuszczyński

    2013-12-01

    Full Text Available The paper presents information on Leucopaxillus lepistoides (Maire Singer, a new species for Poland. This fungus was found in two localities: the neighbourhood of Busko Zdrój and Chęciny (Little Polish Upland, S-Poland. Both localities were in the xerothermic grasslands belonging to the Cirsio-Brachypodion Order, Festuco-Brometea Class.

  7. Lignocellulose pretreatment in a fungus-cultivating termite

    Science.gov (United States)

    Hongjie Li; Daniel J. Yelle; Chang Li; Mengyi Yang; Jing Ke; Ruijuan Zhang; Yu Liu; Na Zhu; Shiyou Liang; Xiaochang Mo; John Ralph; Cameron R. Currie; Jianchu Mo

    2017-01-01

    Depolymerizing lignin, the complex phenolic polymer fortifying plant cell walls, is an essential but challenging starting point for the lignocellulosics industries. The variety of ether– and carbon–carbon interunit linkages produced via radical coupling during lignification limit chemical and biological depolymerization efficiency. In an ancient fungus-cultivating...

  8. The development and endophytic nature of the fungus Heteroconium chaetospira.

    Science.gov (United States)

    Hashiba, Teruyoshi; Narisawa, Kazuhiko

    2005-11-15

    The root endophytic fungus Heteroconium chaetospira was isolated from roots of Chinese cabbage grown in field soil in Japan. This fungus penetrates through the outer epidermal cells of its host, passes into the inner cortex, and grows throughout the cortical cells, including those of the root tip region, without causing apparent pathogenic symptoms. There are no ultrastructural signs of host resistance responses. H. chaetospira has been recovered from 19 plant species in which there was no disruption of host growth. H. chaetospira has a symbiotic association with Chinese cabbage. The fungus provides nitrogen in exchange for carbon. These associations are beneficial for the inoculated plants, as demonstrated by increased growth rate. When used as a preinoculum, H. chaetospira suppresses the incidence of clubroot and Verticillium yellows when the test plant is post-inoculated with the causal agents of these diseases. H. chaetospira is an effective biocontrol agent against clubroot in Chinese cabbage at a low to moderate soil moisture range and a pathogen resting spore density of 10(5) resting spores per gram of soil in situ. Disease caused by Pseudomonas syringae pv. macricola and Alternaria brassicae on leaves can be suppressed by treatment with H. chaetospira. The fungus persists in the roots and induces systemic resistance to the foliar disease.

  9. Directed Evolution of a Filamentous Fungus for Thermotolerance

    Science.gov (United States)

    Filamentous fungi represent the most widely used eukaryotic biocatalysts in industrial and chemical applications. Metarhizium anisopliae is a broad-host-range entomopathogenic fungus currently under intensive investigation as a biologically based alternative to chemical pesticides. One of the most p...

  10. DNA dependent RNA polymerases from the fungus Aspergillus nidulans

    NARCIS (Netherlands)

    Stunnenberg, H.G.

    1981-01-01

    The aim of the work presented here was the isolation and characterization of the DNA-dependent RNA polymerases from the fungus Aspergillus nidulans, which was a part of a project concerning the regulation of gene expression in this lower eukaryote.The transcription of a genome and the regulation mec

  11. Rethinking crop-disease management in fungus-growing ants

    NARCIS (Netherlands)

    Boomsma, J.J.; Aanen, D.K.

    2009-01-01

    Ant fungus farming has become a prominent model for studying the evolution of mutualistic cooperation, with recent advances in reconstructing the evolutionary origin and elaborations of the symbiosis (1, 2), discovering additional partners and clarifying their interactions (3, 4), and analyzing host

  12. Volatile antimicrobials from Muscodor crispans, a novel endophytic fungus.

    Science.gov (United States)

    Mitchell, Angela M; Strobel, Gary A; Moore, Emily; Robison, Richard; Sears, Joe

    2010-01-01

    Muscodor crispans is a recently described novel endophytic fungus of Ananas ananassoides (wild pineapple) growing in the Bolivian Amazon Basin. The fungus produces a mixture of volatile organic compounds (VOCs); some of the major components of this mixture, as determined by GC/MS, are propanoic acid, 2-methyl-, methyl ester; propanoic acid, 2-methyl-; 1-butanol, 3-methyl-;1-butanol, 3-methyl-, acetate; propanoic acid, 2-methyl-, 2-methylbutyl ester; and ethanol. The fungus does not, however, produce naphthalene or azulene derivatives as has been observed with many other members of the genus Muscodor. The mixture of VOCs produced by M. crispans cultures possesses antibiotic properties, as does an artificial mixture of a majority of the components. The VOCs of the fungus are effective against a wide range of plant pathogens, including the fungi Pythium ultimum, Phytophthora cinnamomi, Sclerotinia sclerotiorum and Mycosphaerella fijiensis (the black sigatoka pathogen of bananas), and the serious bacterial pathogen of citrus, Xanthomonas axonopodis pv. citri. In addition, the VOCs of M. crispans killed several human pathogens, including Yersinia pestis, Mycobacterium tuberculosis and Staphylococcus aureus. Artificial mixtures of the fungal VOCs were both inhibitory and lethal to a number of human and plant pathogens, including three drug-resistant strains of Mycobacterium tuberculosis. The gaseous products of Muscodor crispans potentially could prove to be beneficial in the fields of medicine, agriculture, and industry.

  13. Controlling fungus on channel catfish eggs with peracetic acid

    Science.gov (United States)

    There is much interest in the use of peracetic acid (PAA) to treat pathogens in aquaculture. It is a relatively new compound and is approved for use in Europe, but not in the United States. This study determined the effectiveness of PAA for fungus control on channel catfish Ictalurus punctatus egg...

  14. An entomopathogenic fungus for control of adult African malaria mosquitoes

    NARCIS (Netherlands)

    Scholte, E.J.; Ng'habi, K.R.N.; Kihonda, J.; Takken, W.; Paaijmans, K.P.; Abdulla, S.; Killeen, G.F.; Knols, B.G.J.

    2005-01-01

    Biological control of malaria mosquitoes in Africa has rarely been used in vector control programs. Recent developments in this field show that certain fungi are virulent to adult Anopheles mosquitoes. Practical delivery of an entomopathogenic fungus that infected and killed adult Anopheles gambiae,

  15. Fun Microbiology: How To Measure Growth of a Fungus.

    Science.gov (United States)

    Mitchell, James K.; And Others

    1997-01-01

    Describes an experiment to demonstrate a simple method for measuring fungus growth by monitoring the effect of temperature on the growth of Trichoderma viride. Among the advantages that this experimental model provides is introducing students to the importance of using the computer as a scientific tool for analyzing and presenting data. (AIM)

  16. OXIDATION OF PERSISTANT ENVIRONMENTAL POLLUTANTS BY A WHITE ROT FUNGUS

    Science.gov (United States)

    The white rot fungus Phanerochaete chrysosporium degraded DDT [1,1,-bis(4-chlorophenyl)-2,2,2-trichloroethane], 3,4,3',4'-tetrachlorobiphenyl, 2,4,5,2',-4',5'-hexachlorobiphenyl, 2,3,7,8-tetrachlorodibenzo-p-dioxin, lindane (1,2,3,4,5,6-hexachlorocylohexane), and benzo[a]pyrene t...

  17. A Brazilian social bee must cultivate fungus to survive.

    Science.gov (United States)

    Menezes, Cristiano; Vollet-Neto, Ayrton; Marsaioli, Anita Jocelyne; Zampieri, Davila; Fontoura, Isabela Cardoso; Luchessi, Augusto Ducati; Imperatriz-Fonseca, Vera Lucia

    2015-11-02

    The nests of social insects provide suitable microenvironments for many microorganisms as they offer stable environmental conditions and a rich source of food [1-4]. Microorganisms in turn may provide several benefits to their hosts, such as nutrients and protection against pathogens [1, 4-6]. Several examples of symbiosis between social insects and microorganisms have been found in ants and termites. These symbioses have driven the evolution of complex behaviors and nest structures associated with the culturing of the symbiotic microorganisms [5, 7, 8]. However, while much is known about these relationships in many species of ants and termites, symbiotic relationships between microorganisms and social bees have been poorly explored [3, 4, 9, 10]. Here, we report the first case of an obligatory relationship between the Brazilian stingless bee Scaptotrigona depilis and a fungus of the genus Monascus (Ascomycotina). Fungal mycelia growing on the provisioned food inside the brood cell are eaten by the larva. Larvae reared in vitro on sterilized larval food supplemented with fungal mycelia had a much higher survival rate (76%) compared to larvae reared under identical conditions but without fungal mycelia (8% survival). The fungus was found to originate from the material from which the brood cells are made. Since the bees recycle and transport this material between nests, fungus would be transferred to newly built cells and also to newly founded nests. This is the first report of a fungus cultivation mutualism in a social bee.

  18. An Abietane Diterpene and a Sterol from Fungus Phellinus igniarius

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A new abietane diterpene 12-hydroxy-7-oxo-5, 8, 11, 13-tetraene-18, 6-abietanolide,together with a new natural sterol stigmasta-7, 22-diene-3β, 5α, 6α-triol have been isolated from the fruiting body of the fungus Phellinus igniarius. Their structures were elucidated by spectroscopic methods including 2D NMR techniques.

  19. Analysis of a Functional Lactate Permease in the Fungus Rhizopus

    Science.gov (United States)

    The fungus Rhizopus is frequently used for fermentative production of lactic acid, but little is known about the mechanisms or proteins for transporting this carboxylic acid. Since transport of the lactate anion across the plasma membrane is critical to prevent acidification of the cytoplasm, we ev...

  20. DNA-dependent RNA polymerases from the fungus Aspergillus nidulans

    NARCIS (Netherlands)

    Stunnenberg, H.G.

    1981-01-01

    The aim of the work presented here was the isolation and characterization of the DNA-dependent RNA polymerases from the fungus Aspergillus nidulans, which was a part of a project concerning the regulation of gene expression in this lower eukaryote.

    The transcription of

  1. Endophytic fungus-vascular plant-insect interactions.

    Science.gov (United States)

    Raman, A; Wheatley, W; Popay, A

    2012-06-01

    Insect association with fungi has a long history. Theories dealing with the evolution of insect herbivory indicate that insects used microbes including fungi as their principal food materials before flowering plants evolved. Subtlety and the level of intricacy in the interactions between insects and fungi indicate symbiosis as the predominant ecological pattern. The nature of the symbiotic interaction that occurs between two organisms (the insect and the fungus), may be either mutualistic or parasitic, or between these two extremes. However, the triangular relationship involving three organisms, viz., an insect, a fungus, and a vascular plant is a relationship that is more complicated than what can be described as either mutualism or parasitism, and may represent facets of both. Recent research has revealed such a complex relationship in the vertically transmitted type-I endophytes living within agriculturally important grasses and the pestiferous insects that attack them. The intricacy of the association depends on the endophytic fungus-grass association and the insect present. Secondary compounds produced in the endophytic fungus-grass association can provide grasses with resistance to herbivores resulting in mutualistic relationship between the fungus and the plant that has negative consequences for herbivorous insects. The horizontally transmitted nongrass type-II endophytes are far less well studied and as such their ecological roles are not fully understood. This forum article explores the intricacy of dependence in such complex triangular relationships drawing from well-established examples from the fungi that live as endophytes in vascular plants and how they impact on the biology and evolution of free-living as well as concealed (e.g., gall-inducing, gall-inhabiting) insects. Recent developments with the inoculation of strains of type-I fungal endophytes into grasses and their commercialization are discussed, along with the possible roles the endophytic

  2. Morphophysiological Differences between the Metapleural Glands of Fungus-Growing and Non–Fungus-Growing Ants (Hymenoptera, Formicidae)

    Science.gov (United States)

    Vieira, Alexsandro Santana; Bueno, Odair Correa; Camargo-Mathias, Maria Izabel

    2012-01-01

    The metapleural gland is an organ exclusive to ants. Its main role is to produce secretions that inhibit the proliferation of different types of pathogens. The aim of the present study was to examine the morphophysiological differences between the metapleural gland of 3 non–fungus-growing ants of the tribes Ectatommini, Myrmicini, and Blepharidattini and that of 5 fungus-growing ants from 2 basal and 3 derived attine genera. The metapleural gland of the non–fungus-growing ants and the basal attine ants has fewer secretory cells than that of the derived attine ants (leaf-cutting ants). In addition, the metapleural gland of the latter had more clusters of secretory cells and sieve plates, indicating a greater storage capacity and demand for secretion in these more advanced farming ants. The glands of the derived attine ants also produced higher levels of polysaccharides and acidic lipids than those of Myrmicini, Blepharidattini, and basal attines. Our results confirm morphophysiological differences between the metapleural glands of the derived attines and those of the basal attines and non–fungus-growing ants, suggesting that the metapleural glands of the derived attines (leaf-cutting ants) are more developed in morphology and physiology, with enhanced secretion production (acidic lipids and protein) to protect against the proliferation of unwanted fungi and bacteria in the fungal garden, it is possible that leaf-cutting ants may have evolved more developed metapleural glands in response to stronger pressure from parasites. PMID:22927993

  3. Morphophysiological differences between the metapleural glands of fungus-growing and non-fungus-growing ants (Hymenoptera, Formicidae).

    Science.gov (United States)

    Vieira, Alexsandro Santana; Bueno, Odair Correa; Camargo-Mathias, Maria Izabel

    2012-01-01

    The metapleural gland is an organ exclusive to ants. Its main role is to produce secretions that inhibit the proliferation of different types of pathogens. The aim of the present study was to examine the morphophysiological differences between the metapleural gland of 3 non-fungus-growing ants of the tribes Ectatommini, Myrmicini, and Blepharidattini and that of 5 fungus-growing ants from 2 basal and 3 derived attine genera. The metapleural gland of the non-fungus-growing ants and the basal attine ants has fewer secretory cells than that of the derived attine ants (leaf-cutting ants). In addition, the metapleural gland of the latter had more clusters of secretory cells and sieve plates, indicating a greater storage capacity and demand for secretion in these more advanced farming ants. The glands of the derived attine ants also produced higher levels of polysaccharides and acidic lipids than those of Myrmicini, Blepharidattini, and basal attines. Our results confirm morphophysiological differences between the metapleural glands of the derived attines and those of the basal attines and non-fungus-growing ants, suggesting that the metapleural glands of the derived attines (leaf-cutting ants) are more developed in morphology and physiology, with enhanced secretion production (acidic lipids and protein) to protect against the proliferation of unwanted fungi and bacteria in the fungal garden, it is possible that leaf-cutting ants may have evolved more developed metapleural glands in response to stronger pressure from parasites.

  4. Draft genome of the fungus-growing termite pathogenic fungus Ophiocordyceps bispora (Ophiocordycipitaceae, Hypocreales, Ascomycota).

    Science.gov (United States)

    Conlon, Benjamin H; Mitchell, Jannette; de Beer, Z Wilhelm; Carøe, Christian; Gilbert, M Thomas P; Eilenberg, Jørgen; Poulsen, Michael; de Fine Licht, Henrik H

    2017-04-01

    This article documents the public availability of genome sequence data and assembled contigs representing the partial draft genome of Ophiocordyceps bispora. As one of the few known pathogens of fungus-farming termites, a draft genome of O. bispora represents the opportunity to further the understanding of disease and resistance in these complex termite societies. With the ongoing attempts to resolve the taxonomy of the Hypocralaean family, more genetic data will also help to shed light on the phylogenetic relationship between sexual and asexual life stages. Next generation sequence data is available from the European Nucleotide Archive (ENA) under accession PRJEB13655; run numbers: ERR1368522, ERR1368523, and ERR1368524. Genome assembly available from ENA under accession numbers: FKNF01000001-FKNF01000302. Gene prediction available as protein fasta, nucleotide fasta and GFF file from Mendeley Data with accession doi:10.17632/r99fd6g3s4.2 (http://dx.doi.org/10.17632/r99fd6g3s4.2).

  5. Draft genome of the fungus-growing termite pathogenic fungus Ophiocordyceps bispora (Ophiocordycipitaceae, Hypocreales, Ascomycota

    Directory of Open Access Journals (Sweden)

    Benjamin H. Conlon

    2017-04-01

    Full Text Available This article documents the public availability of genome sequence data and assembled contigs representing the partial draft genome of Ophiocordyceps bispora. As one of the few known pathogens of fungus-farming termites, a draft genome of O. bispora represents the opportunity to further the understanding of disease and resistance in these complex termite societies. With the ongoing attempts to resolve the taxonomy of the Hypocralaean family, more genetic data will also help to shed light on the phylogenetic relationship between sexual and asexual life stages. Next generation sequence data is available from the European Nucleotide Archive (ENA under accession PRJEB13655; run numbers: ERR1368522, ERR1368523, and ERR1368524. Genome assembly available from ENA under accession numbers: FKNF01000001–FKNF01000302. Gene prediction available as protein fasta, nucleotide fasta and GFF file from Mendeley Data with accession doi:10.17632/r99fd6g3s4.2 (http://dx.doi.org/10.17632/r99fd6g3s4.2.

  6. Gaeumannomyces graminis, the take-all fungus and its relatives.

    Science.gov (United States)

    Freeman, Jacqueline; Ward, Elaine

    2004-07-01

    SUMMARY Take-all, caused by the fungus Gaeumannomyces graminis var. tritici, is the most important root disease of wheat worldwide. Many years of intensive research, reflected by the large volume of literature on take-all, has led to a considerable degree of understanding of many aspects of the disease. However, effective and economic control of the disease remains difficult. The application of molecular techniques to study G. graminis and related fungi has resulted in some significant advances, particularly in the development of improved methods for identification and in elucidating the role of the enzyme avenacinase as a pathogenicity determinant in the closely related oat take-all fungus (G. graminis var. avenae). Some progress in identifying other factors that may be involved in determining host range and pathogenicity has been made, despite the difficulties of performing genetic analyses and the lack of a reliable transformation system.

  7. Potential for nitrogen fixation in fungus-growing termite symbiosis

    DEFF Research Database (Denmark)

    Sapountzis, Panagiotis; de Verges, Jane; Rousk, Kathrin

    2016-01-01

    Termites host a gut microbiota of diverse and essential symbionts that enable specialization on dead plant material; an abundant, but nutritionally imbalanced food source. To supplement the severe shortage of dietary nitrogen (N), some termite species make use of diazotrophic bacteria to fix...... atmospheric nitrogen (N2). Fungus-growing termites (subfamily Macrotermitinae) host a fungal exosymbiont (genus Termitomyces) that provides digestive services and the main food source for the termites. This has been thought to obviate the need for N2-fixation by bacterial symbionts. Here, we challenge...... this notion by performing acetylene reduction assays of live colony material to show that N2 fixation is present in two major genera (Macrotermes and Odontotermes) of fungus-growing termites. We compare and discuss fixation rates in relation to those obtained from other termites, and suggest avenues...

  8. Formulation of the endophytic fungus Cladosporium oxysporum Berk.

    Directory of Open Access Journals (Sweden)

    Bensaci Oussama Ali

    2015-01-01

    Full Text Available Two formulations containing culture filtrates and conidial suspensions of the endophytic fungus Cladosporium oxysporum Berk. & M.A. Curtis, isolated previously from stems of Euphorbia bupleuroides subsp. luteola (Kralik Maire, were experimentally tested for their aphicid activity against the black bean aphid Aphis fabae Scop. found in Algeria. It was shown that invert emulsions are more effective against aphids, than using aqueous suspensions. This was especially true for formulations containing culture filtrates. The relatively insignificant mortalities obtained by formulations containing conidial suspensions indicated a low infectious potential towards the aphids. The proteolytic activity seemed to be more important than the chitinolytic activity of the fungus against the black bean aphid A. fabae

  9. Secondary metabolite arsenal of an opportunistic pathogenic fungus.

    Science.gov (United States)

    Bignell, Elaine; Cairns, Timothy C; Throckmorton, Kurt; Nierman, William C; Keller, Nancy P

    2016-12-05

    Aspergillus fumigatus is a versatile fungus able to successfully exploit diverse environments from mammalian lungs to agricultural waste products. Among its many fitness attributes are dozens of genetic loci containing biosynthetic gene clusters (BGCs) producing bioactive small molecules (often referred to as secondary metabolites or natural products) that provide growth advantages to the fungus dependent on environment. Here we summarize the current knowledge of these BGCs-18 of which can be named to product-their expression profiles in vivo, and which BGCs may enhance virulence of this opportunistic human pathogen. Furthermore, we find extensive evidence for the presence of many of these BGCs, or similar BGCs, in distantly related genera including the emerging pathogen Pseudogymnoascus destructans, the causative agent of white-nose syndrome in bats, and suggest such BGCs may be predictive of pathogenic potential in other fungi.This article is part of the themed issue 'Tackling emerging fungal threats to animal health, food security and ecosystem resilience'.

  10. Synthetic dye decolorization capacity of white rot fungus Dichomitus squalens.

    Science.gov (United States)

    Eichlerová, Ivana; Homolka, Ladislav; Nerud, Frantisek

    2006-11-01

    The ability to decolorize eight chemically different synthetic dyes (Orange G, Amaranth, Orange I, Remazol Brilliant Blue R (RBBR), Cu-phthalocyanin, Poly R-478, Malachite Green and Crystal Violet) by the white rot fungus Dichomitus squalens was evaluated on agar plates. The fungus showed high decolorization capacity and was able to decolorize all dyes tested, but not to the same extent. Some of the dyes did not limit the decolorization capacity of the strain tested even at a concentration of 2g/l. The presence of the dyes in solid media reduced the mycelial growth rate of D. squalens; a positive correlation was found between the growth rate and the decolorization ability. Decolorization of Orange G and RBBR was studied also in liquid culture, where both dyes caused an enhancement of ligninolytic enzyme and overall hydrogen peroxide production and a decrease of biomass production. RBBR was removed to a higher extent than Orange G.

  11. Fungus-associated asthma: overcoming challenges in diagnosis and treatment.

    Science.gov (United States)

    Ogawa, Haruhiko; Fujimura, Masaki; Ohkura, Noriyuki; Satoh, Kazuo; Makimura, Koichi

    2014-05-01

    With regard to fungal colonization and fungal sensitization, the goals of fungus-associated asthma management are as follows: 1) to survey fungi colonizing the airways of patients repeatedly; 2) to evaluate the tendency of the colonizing fungi to sensitize patients and the influence on clinical manifestations of asthma; 3) to follow disease development to allergic bronchopulmonary mycosis or sinobronchial allergic mycosis; and 4) to determine whether fungal eradication from the airway of patients is beneficial from the viewpoints of future risk factors. Recent developments in molecular biological analyses have facilitated the identification of basidiomycetous fungi that were not previously thought to be of concern in fungal allergy. The total control of fungus-associated asthma will be accomplished by environmental management established from the viewpoint of both the ecology and life cycle of the responsible fungi.

  12. Four Novel Hydropyranoindeno- Derivatives from Marine Fungus Aspergillus versicolor

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    From the cultured filtrates of fungus Aspergillus versicolor,isolated from marine sponge Xestospongia exigua,four novel secondary metabolites,namely aspergillone 1,aspergillodiol 2, aspergillol 3 and 12-acetyl-aspergillol 4,have been isolated by column chromatographic separation.The structures of all the new compounds are established on the basis of extensive 2D NMR spectroscopy in conjugation with MS,UV spectral analysis.The basic structure pattern of those compounds possessed an hydroindenoisopyran nucleus.

  13. Biotransformation of fluorene by the fungus Cunninghamella elegans

    Energy Technology Data Exchange (ETDEWEB)

    Pothuluri, J.V.; Freeman, J.P.; Evans, F.E.; Cerniglia, C.E. (Food and Drug Administration, Jefferson, AR (United States))

    1993-06-01

    Fluorene, a tricyclic aromatic hydrocarbon, is formed during the combustion of fossil fuels and is an important pollutant of aquatic ecosystems where it is highly toxic to fish and algae. Few studies on microbial biodegradation of fluorene have been reported. This investigation describes the metabolism of fluorene by the fungus Cunninghamella elegans ATCC 36112 and the identification of major metabolites. 26 refs., 2 figs., 1 tab.

  14. Oxygenated lanostane-type triterpenoids from the fungus ganodermalucidum.

    Science.gov (United States)

    Akihisa, Toshihiro; Tagata, Masaaki; Ukiya, Motohiko; Tokuda, Harukuni; Suzuki, Takashi; Kimura, Yumiko

    2005-04-01

    Two new triterpenoids, 20(21)-dehydrolucidenic acid A (1) and methyl 20(21)-dehydrolucidenate A (2), and five new 20-hydroxylucidenic acids, 20-hydroxylucidenic acid D(2) (3), 20-hydroxylucidenic acid F (4), 20-hydroxylucidenic acid E(2) (5), 20-hydroxylucidenic acid N (6), and 20-hydroxylucidenic acid P (7), were isolated from the fruiting body of the fungus Ganoderma ludicum, and their structures were established on the basis of spectroscopic methods.

  15. a -Difluoromethylornithine Inhibits the Growth of Fungus Macrophomina phaseoli

    OpenAIRE

    PALAVAN-ÜNSAL, Narçin

    2014-01-01

    a -Difluoromethylornithine (DFMO), a specific enzyme activated inhibitor of ornithine decarboxylase (ODC), significantly inhibited the mycelial growth of the fungus Macrophomina phaseoli (Tassi) Goidanich. Putrescine (Put), when added to the nutrient medium at a concentration of 0.25 mM, decreased the inhibitory effect of DFMO. These results suggest that polyamines (PAs) are essential for the growth of fungi and that DFMO is applicable to the alleviation or prevention of crop losses due to ph...

  16. Identification and characterization of glucoamylase from the fungus, Thermomyces lanuginosus

    DEFF Research Database (Denmark)

    Thorsen, Thor Seneca; Johnsen, Anders; Josefsen, K.;

    2006-01-01

    The glucoamylase from the thermophilic fungus Thermomyces lanuginosus has a molecular weight of 66 kDa and was characterized with isoelectric point, pH and temperature optimum of 3.8-4.0, 5.0 and 70 °C, respectively. In addition, the activation energy is 60.4 kJ/mol, Km is 3.5 mM and kcat is 25.3...

  17. A New Pyrone Derivative from Fungus Cephalosporium sp. AL031

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A novel pyrone derivative was isolated from the ethyl acetate extract of a culture broth of a strain of the fungus Cephalosporium sp. AL031. Its structure was characterized as 7-hydroxy-9-methoxyl-10-methyl-2H, 4aH, 6H, 10bH-pyrano[5, 6-c][2]benzopyran-2, 6-dione by spectroscopic analysis including IR, MS, 1D and 2D NMR spectra.

  18. Cytochalasin derivatives from a jellyfish-derived fungus Phoma sp.

    Science.gov (United States)

    Kim, Eun La; Wang, Haibo; Park, Ju Hee; Hong, Jongki; Choi, Jae Sue; Im, Dong Soon; Chung, Hae Young; Jung, Jee H

    2015-01-01

    Four new cytochalasin derivatives (1-4), together with proxiphomin (5), were isolated from a jellyfish-derived fungus Phoma sp. The planar structures and relative stereochemistry were established by analysis of 1D and 2D NMR data. The absolute configuration was defined by the modified Mosher's method. The compounds showed moderate cytotoxicity against a small panel of human solid tumor cell lines (A549, KB, and HCT116).

  19. Symbiotic Fungus of Marine Sponge Axinella sp. Producing Antibacterial Agent

    Science.gov (United States)

    Trianto, A.; Widyaningsih, S.; Radjasa, OK; Pribadi, R.

    2017-02-01

    The emerging of multidrug resistance pathogenic bacteria cause the treatment of the diseaseshave become ineffective. There for, invention of a new drug with novel mode of action is an essential for curing the disease caused by an MDR pathogen. Marine fungi is prolific source of bioactive compound that has not been well explored. This study aim to obtain the marine sponges-associated fungus that producing anti-MDR bacteria substaces. We collected the sponge from Riung water, NTT, Indonesia. The fungus was isolated with affixed method, followed with purification with streak method. The overlay and disk diffusion agar methods were applied for bioactivity test for the isolate and the extract, respectively. Molecular analysis was employed for identification of the isolate. The sponge was identified based on morphological and spicular analysis. The ovelay test showed that the isolate KN15-3 active against the MDR Staphylococcus aureus and Eschericia coli. The extract of the cultured KN15-3 was also inhibited the S. aureus and E. coli with inhibition zone 2.95 mm and 4.13 mm, respectively. Based on the molecular analysis, the fungus was identified as Aspergillus sydowii. While the sponge was identified as Axinella sp.

  20. Biodegradation of polyethylene microplastics by the marine fungus Zalerion maritimum.

    Science.gov (United States)

    Paço, Ana; Duarte, Kátia; da Costa, João P; Santos, Patrícia S M; Pereira, R; Pereira, M E; Freitas, Ana C; Duarte, Armando C; Rocha-Santos, Teresa A P

    2017-05-15

    Plastic yearly production has surpassed the 300milliontons mark and recycling has all but failed in constituting a viable solution for the disposal of plastic waste. As these materials continue to accumulate in the environment, namely, in rivers and oceans, in the form of macro-, meso-, micro- and nanoplastics, it becomes of the utmost urgency to find new ways to curtail this environmental threat. Multiple efforts have been made to identify and isolate microorganisms capable of utilizing synthetic polymers and recent results point towards the viability of a solution for this problem based on the biodegradation of plastics resorting to selected microbial strains. Herein, the response of the fungus Zalerion maritimum to different times of exposition to polyethylene (PE) pellets, in a minimum growth medium, was evaluated, based on the quantified mass differences in both the fungus and the microplastic pellets used. Additionally, molecular changes were assessed through attenuated total reflectance Fourier transform Infrared Spectroscopy (FTIR-ATR) and Nuclear Magnetic Resonance (NMR). Results showed that, under the tested conditions, Z. maritimum is capable of utilizing PE, resulting in the decrease, in both mass and size, of the pellets. These results indicate that this naturally occurring fungus may actively contribute to the biodegradation of microplastics, requiring minimum nutrients.

  1. Evolutionary transitions in enzyme activity of ant fungus gardens.

    Science.gov (United States)

    De Fine Licht, Henrik H; Schiøtt, Morten; Mueller, Ulrich G; Boomsma, Jacobus J

    2010-07-01

    Fungus-growing (attine) ants and their fungal symbionts passed through several evolutionary transitions during their 50 million year old evolutionary history. The basal attine lineages often shifted between two main cultivar clades, whereas the derived higher-attine lineages maintained an association with a monophyletic clade of specialized symbionts. In conjunction with the transition to specialized symbionts, the ants advanced in colony size and social complexity. Here we provide a comparative study of the functional specialization in extracellular enzyme activities in fungus gardens across the attine phylogeny. We show that, relative to sister clades, gardens of higher-attine ants have enhanced activity of protein-digesting enzymes, whereas gardens of leaf-cutting ants also have increased activity of starch-digesting enzymes. However, the enzyme activities of lower-attine fungus gardens are targeted primarily toward partial degradation of plant cell walls, reflecting a plesiomorphic state of nondomesticated fungi. The enzyme profiles of the higher-attine and leaf-cutting gardens appear particularly suited to digest fresh plant materials and to access nutrients from live cells without major breakdown of cell walls. The adaptive significance of the lower-attine symbiont shifts remains unclear. One of these shifts was obligate, but digestive advantages remained ambiguous, whereas the other remained facultative despite providing greater digestive efficiency.

  2. Decomposition of Plant Debris by the Nematophagous Fungus ARF.

    Science.gov (United States)

    Wang, Kening; Riggs, R D; Crippen, Devany

    2004-09-01

    In the study of the biological control of plant-parasitic nematodes, knowledge of the saprophytic ability of a nematophagous fungus is necessary to understand its establishment and survival in the soil. The objectives of this study were (i) to determine if the nematophagous fungus ARF (Arkansas Fungus) shows differential use of plant residues; and (ii) to determine if ARF still existed in the soil of a field in which ARF was found originally and in which the population level of Heterodera glycines had remained very low, despite 15 years of continuous, susceptible soybean. Laboratory studies of the decomposition of wheat straw or soybean root by ARF were conducted in two separate experiments, using a CO collection apparatus, where CO-free air was passed through sterilized cotton to remove the microorganisms in the air and then was passed over the samples, and evolved CO was trapped by KOH. Milligrams of C as CO was used to calculate the percentage decomposition of the plant debris by ARF. Data indicated ARF decomposed 11.7% of total organic carbon of the wheat straw and 20.1% of the soybean roots in 6 weeks. In the field soil study, 21 soil samples were taken randomly from the field. Only 3 months after the infestation of the soil with H. glycines, the percentage of parasitized eggs of H. glycines reached 64 +/- 19%, and ARF was isolated from most parasitized eggs of H. glycines. Research results indicated ARF could use plant residues to survive.

  3. Studies on durable resistance of rice to blast in different latitudes

    Institute of Scientific and Technical Information of China (English)

    LIUErming; PENGShaoqiu; HUANGFeiyuan; XIAOFanghua

    1996-01-01

    It has been an important problem on resistant breeding that cultivar's resistance of rice to blast disease eaused by Magnaporthe grisea(Hebert)Barr. is easily broken down. In order to find out resources with durable, resistance to blast, the study was carried put during 1990-1994.

  4. Dicty_cDB: SHJ401 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available bidopsis thaliana cDNA clone 1161972 5', mRNAsequence. 42 0.097 2 CD036035 |CD036035.1 mgmt...004xA15f.b Mated culture Magnaporthe grisea cDNA clone mgmt004xA15 5', mRNA sequence. 46 1.0 1 AC1

  5. Dicty_cDB: SSD216 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SEQUENCE, 13 unordered pieces. 52 0.008 1 CD035209 |CD035209.1 mgmt019xA08f.b Ma...ted culture Magnaporthe grisea cDNA clone mgmt019xA08 5', mRNA sequence. 52 0.008 1 AF160643 |AF160643.2 D02

  6. Dicty_cDB: CFI288 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available linkage group 20. 40 2.4 3 CD030222 |CD030222.1 mgmt001xN19f.b Mated culture Mag...naporthe grisea cDNA clone mgmt001xN19 5', mRNA sequence. 32 2.5 2 dna update 2003.12.19 Homology vs Protein

  7. Dicty_cDB: SFJ609 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 2 CD036313 |CD036313.1 mgmt015xA07f.b Mated culture Magnaporthe grisea cDNA clone mgmt015xA07 5', mRNA seque...ea Aphid Acyrthosiphon pisum cDNA clone WHAP-002_A12 5', mRNA sequence. 50 3e-04

  8. Dicty_cDB: FC-BI13 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available pisum, Pea Aphid Acyrthosiphon pisum cDNA clone WHAP-002_A12 5', mRNA sequence. 50 3e-04 2 CD036313 |CD036313.1 mgmt...015xA07f.b Mated culture Magnaporthe grisea cDNA clone mgmt015xA07 5', mR

  9. Dicty_cDB: CHA810 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available **, 2 unordered pieces. 34 0.12 5 CD036316 |CD036316.1 mgmt015xC16f.b Mated cultu...re Magnaporthe grisea cDNA clone mgmt015xC16 5', mRNA sequence. 48 0.16 1 AC015216 |AC015216.1 Drosophila me

  10. Synthetic Biomimetic Fluorophores for Micro/Nanosensor

    Science.gov (United States)

    2006-11-01

    Transport proteins in blood plasma bind and carry specific molecules or ions from one organ to another. Other proteins are specialized for nutrients ...cytoplasmic fluorescent proteins for live-cell imaging of Magnaporthe grisea in planta . Mycologia 94: 280-289. Davenport, DN, 1955: JAC: Luminescence in

  11. Comparison and Selection of Organization Modes in Edible Fungus Industry of Shandong Province

    Institute of Scientific and Technical Information of China (English)

    Yanxiang; GE; Jilian; HU; Zhijian; GUO

    2013-01-01

    China is the largest producer and exporter of edible fungus in the world,and Shandong is the largest producer of edible fungus in China.This study is intended to select suitable organization mode for edible fungus industry of Shandong Province.On the basis of types and characteristics of existing edible fungus production modes in China,it is concluded that Shandong Province should take following measures:(1)giving priority to development of integrated organization mode;(2)steadily promoting park and factory mode in economically developed regions;(3)developing circular agriculture in regions with solid foundation of agriculture and animal husbandry.Finally,it puts forward following recommendations:(1)speeding up construction of standardization and information platform for edible fungus industry;(2)improving quality of personnel engaged in edible fungus industry;(3)bringing into play driving effect of leading enterprises;(4)developing and introducing deep processing enterprises.

  12. Degradation of Phenanthrene by a chilean white rot fungus Anthracophyllum discolor

    Energy Technology Data Exchange (ETDEWEB)

    Acevedo, F.; Cuevas, R.; Rubilar, O.; Tortella, G.; Diez, M. C.

    2009-07-01

    Anthracophyllum discolor, a white rot fungus of southern Chile, has been an efficient degrader of clorophenols and azo dyes. This fungus produces ligninolytic enzymes being manganese peroxidase (Mn) the major one produced. The main purpose of this study was to evaluate the effect of phenanthrene concentration of ligninolytic activity of A. Discolor measured by poly R-478 decolorazation, and to evaluate the potential of this fungus for degrading phenanthrene in liquid media. (Author)

  13. Isolated fungal promoters and gene transcription terminators and methods of protein and chemical production in a fungus

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Ziyu; Lasure, Linda L; Magnuson, Jon K

    2014-05-27

    The present invention encompasses isolated gene regulatory elements and gene transcription terminators that are differentially expressed in a native fungus exhibiting a first morphology relative to the native fungus exhibiting a second morphology. The invention also encompasses a method of utilizing a fungus for protein or chemical production. A transformed fungus is produced by transforming a fungus with a recombinant polynucleotide molecule. The recombinant polynucleotide molecule contains an isolated polynucleotide sequence linked operably to another molecule comprising a coding region of a gene of interest. The gene regulatory element and gene transcription terminator may temporally and spatially regulate expression of particular genes for optimum production of compounds of interest in a transgenic fungus.

  14. Isolated fungal promoters and gene transcription terminators and methods of protein and chemical production in a fungus

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Ziyu; Lasure, Linda L; Magnuson, Jon K

    2014-05-27

    The present invention encompasses isolated gene regulatory elements and gene transcription terminators that are differentially expressed in a native fungus exhibiting a first morphology relative to the native fungus exhibiting a second morphology. The invention also encompasses a method of utilizing a fungus for protein or chemical production. A transformed fungus is produced by transforming a fungus with a recombinant polynucleotide molecule. The recombinant polynucleotide molecule contains an isolated polynucleotide sequence linked operably to another molecule comprising a coding region of a gene of interest. The gene regulatory element and gene transcription terminator may temporally and spatially regulate expression of particular genes for optimum production of compounds of interest in a transgenic fungus.

  15. Isolated Fungal Promoters and Gene Transcription Terminators and Methods of Protein and Chemical Production in a Fungus

    Science.gov (United States)

    Dai, Ziyu; Lasure, Linda L.; Magnuson, Jon K.

    2008-11-11

    The present invention encompasses isolated gene regulatory elements and gene transcription terminators that are differentially expressed in a native fungus exhibiting a first morphology relative to the native fungus exhibiting a second morphology. The invention also encompasses a method of utilizing a fungus for protein or chemical production. A transformed fungus is produced by transforming a fungus with a recombinant polynucleotide molecule. The recombinant polynucleotide molecule contains an isolated polynucleotide sequence linked operably to another molecule comprising a coding region of a gene of interest. The gene regulatory element and gene transcription terminator may temporally and spatially regulate expression of particular genes for optimum production of compounds of interest in a transgenic fungus.

  16. Carbon dioxide sensing in an obligate insect-fungus symbiosis: CO2 preferences of leaf-cutting ants to rear their mutualistic fungus.

    Science.gov (United States)

    Römer, Daniela; Bollazzi, Martin; Roces, Flavio

    2017-01-01

    Defense against biotic or abiotic stresses is one of the benefits of living in symbiosis. Leaf-cutting ants, which live in an obligate mutualism with a fungus, attenuate thermal and desiccation stress of their partner through behavioral responses, by choosing suitable places for fungus-rearing across the soil profile. The underground environment also presents hypoxic (low oxygen) and hypercapnic (high carbon dioxide) conditions, which can negatively influence the symbiont. Here, we investigated whether workers of the leaf-cutting ant Acromyrmex lundii use the CO2 concentration as an orientation cue when selecting a place to locate their fungus garden, and whether they show preferences for specific CO2 concentrations. We also evaluated whether levels preferred by workers for fungus-rearing differ from those selected for themselves. In the laboratory, CO2 preferences were assessed in binary choices between chambers with different CO2 concentrations, by quantifying number of workers in each chamber and amount of relocated fungus. Leaf-cutting ants used the CO2 concentration as a spatial cue when selecting places for fungus-rearing. A. lundii preferred intermediate CO2 levels, between 1 and 3%, as they would encounter at soil depths where their nest chambers are located. In addition, workers avoided both atmospheric and high CO2 levels as they would occur outside the nest and at deeper soil layers, respectively. In order to prevent fungus desiccation, however, workers relocated fungus to high CO2 levels, which were otherwise avoided. Workers' CO2 preferences for themselves showed no clear-cut pattern. We suggest that workers avoid both atmospheric and high CO2 concentrations not because they are detrimental for themselves, but because of their consequences for the symbiotic partner. Whether the preferred CO2 concentrations are beneficial for symbiont growth remains to be investigated, as well as whether the observed preferences for fungus-rearing influences the ants

  17. Anti-Mycobacterium tuberculosis activity of fungus Phomopsis stipata

    Directory of Open Access Journals (Sweden)

    Karina Andrade de Prince

    2012-03-01

    Full Text Available Our purpose was to determine the anti-Mycobacterium tuberculosis activity of the metabolites produced by the endophitic fungus Phomopsis stipata (Lib. B. Sutton, (Diaporthaceae, cultivated in different media. The antimycobacterial activity was assessed through the Resazurin Microtiter Assay (REMA and the cytotoxicity test performed on macrophage cell line. The extracts derived from fungi grown on Corn Medium and Potato Dextrose Broth presented the smallest values of Minimum Inhibitory Concentration (MIC and low cytotoxicity, which implies a high selectivity index. This is the first report on the chemical composition and antitubercular activity of metabolites of P. stipata, as well as the influence of culture medium on these properties.

  18. Cultivation of tea fungus on malt extract medium

    Directory of Open Access Journals (Sweden)

    Cvetković Dragoljub D.

    2002-01-01

    Full Text Available The possibility of application of malt extract as a source of carbohydrate in a medium for tea fungus was investigated. The beverage obtained on such medium was compared with that prepared in a traditional way with sucrose medium. The presence of easily adoptable sugars, glucose and fructose, as dominant in malt medium results in a very effective fermentation, which gives much more sour beverage for the same time and makes it possible to reduce the fermentation period. The obtained beverage has satisfactory sensorial characteristics.

  19. Arsenate resistant Penicillium coffeae: a potential fungus for soil bioremediation.

    Science.gov (United States)

    Bhargavi, S D; Savitha, J

    2014-03-01

    Bioremediation is an effective method for the treatment of major metal contaminated sites. Fungi were isolated from soil samples collected from different arsenate contaminated areas across India. An isolate, Penicillium coffeae, exhibited resistance to arsenate up to 500 mM. Results indicated that pretreatment of biomass with alkali (NaOH) enhanced the percentage of adsorption to 66.8% as compared to that of live and untreated dead biomass whose adsorption was 22.9% and 60.2% respectively. The physiological parameters evaluated in this study may help pilot studies aimed at bioremediation of arsenate contaminated effluents using arsenate resistant fungus P. coffeae.

  20. Microsatellites from the charcoal rot fungus (Macrophomina phaseolina).

    Science.gov (United States)

    Baird, Richard E; Wadl, Phillip A; Wang, Xinwang; Johnson, Denita H; Rinehart, Timothy A; Abbas, Hamed K; Shier, Thomas; Trigiano, Robert N

    2009-05-01

    Microsatellite loci were identified from the charcoal rot fungus (Macrophomina phaseolina). Primer pairs for 46 loci were developed, and of these, 13 were optimized and screened using genomic DNA from 55 fungal isolates collected predominantly from two soybean fields in Mississippi. Twelve of the optimized loci were polymorphic and the number of alleles per locus ranged from 6 to 22. These microsatellites will be useful in population and pathogenicity studies to correspond with development of potential disease-resistant soybean and other susceptible crops. © 2009 Blackwell Publishing Ltd. No claim to original US government works.

  1. Exploitation Strategies in Social Parasites of Fungus Growing Ants

    DEFF Research Database (Denmark)

    Clement, Janni Dolby

    . Inquilines are usually close relatives of their host and so share ancestral characteristics (Emery’s rule). They are dependent on being fully integrated into their host’s colony throughout their lives in order to reproduce. Most inquiline ants have completely lost their sterile worker caste. Exceptions...... to this are Acromyrmex insinuator and Acromyrmex ameliae, parasites of fungus-growing ants. By still producing a worker caste both species offers a rare opportunity to study adaptive features in parasite worker behaviour. Furthermore can closely related inquiline-host combinations give us an insight in the trade...

  2. A New Cerebroside, Asperiamide A, from Marine Fungus Asperillus sp.

    Institute of Scientific and Technical Information of China (English)

    OUYANG,Ming-An; CHEN,Bi-E; KUO,Yueh-Hsiung

    2004-01-01

    @@ Cerebrosides and ceramides[1] have been isolated from a number of marine organisms such as sea stars, sea anemones, gorgonians, sponges, tunicates, dinoflagellates, and green algae. Some cerebroside and ceramides exhibited cytotoxic, antitumor,[2,3] immunostimulatory,[4] antifungal,[5] and antiviral[6] activites. In the search for bioactive components,two water soluble constituents, asperiamide A and adenosine, were isolated from the marine fungus Asperillus sp. The current report describes the structural elucidation of a new compound, aspefiamide A (1) and a known one, adenosine (2).

  3. Two new terpenoids from endophytic fungus Periconia sp. F-31.

    Science.gov (United States)

    Ge, Han-Lin; Zhang, De-Wu; Li, Li; Xie, Dan; Zou, Jian-Hua; Si, Yi-Kang; Dai, Jungui

    2011-01-01

    Two new terpenoids, (+)-(3S,6S,7R,8S)-periconone A (1) and (-)-(1R,4R,6S,7S)-2-caren-4,8-olide (2), have been isolated from an endophytic fungus Periconia sp., which was collected from the plant Annona muricata. Their structures were elucidated on the basis of extensive spectroscopic analyses. In the in vitro assays, the two compounds showed low cytotoxic activities against six human tumor cell lines (HCT-8, Bel-7402, BGC-823, A549, A2780 and MCF-7) with IC(50)>10(-5) M.

  4. BIODEGRADATION OF ENVIRONMENTAL POLLUTANTS BY THE WHITE ROT FUNGUS PHANEROCHAETE CHRYSOPORIUM: INVOLVEMENT OF THE LIGNIN DEGRADING SYSTEM

    Science.gov (United States)

    The white-rot fungus Phanrochaete chrysosporium has the ability to degrade a wide variety of structurally diverse organic compounds, including a number of environmentally persistent organopollutants. The unique biodegradative abilities of this fungus appears to be depend...

  5. First unusual case of keratitis in Europe due to the rare fungus Metarhizium anisopliae.

    Science.gov (United States)

    Dorin, Josephine; Debourgogne, Anne; Zaïdi, Mohamed; Bazard, Marie-Christine; Machouart, Marie

    2015-05-01

    Metarhizium anisopliae is a fungus utilized worldwide for insect-pest biocontrol. Few M. anisopliae infections have been reported previously. Here, M. anisopliae was isolated from a corneal ulcer in a healthy man. It is the first ocular case in France and Europe of this extremely rare fungus in humans.

  6. Two novel eremophilane sesquiterpenes from an endophytic Xylariaceous fungus isolated from leaves of Cupressus lusitanica

    OpenAIRE

    2010-01-01

    Two new eremophilane sesquiterpenes, cupressolide A and cupressolide B, along with two known sesquiterpenes, has been characterized from the EtOAc extract of a liquid medium where a Xylariaceous fungus, isolated as an endophytic fungus from health tissues of Cupressus lusitanica leaves, was cultivated. The structures of the isolated compounds were determined by analyses of their MS and NMR spectroscopic data.

  7. Vertical transmission as the key to the colonization of Madagascar by fungus-growing termites?

    NARCIS (Netherlands)

    Nobre, T.; Eggleton, P.; Aanen, D.K.

    2010-01-01

    The mutualism between fungus-growing termites (Macrotermitinae) and their mutualistic fungi (Termitomyces) began in Africa. The fungus-growing termites have secondarily colonized Madagascar and only a subset of the genera found in Africa is found on this isolated island. Successful long-distance col

  8. Insect symbioses: a case study of past, present, and future fungus-growing ant research

    DEFF Research Database (Denmark)

    Caldera, Eric J; Poulsen, Michael; Suen, Garret

    2009-01-01

    Fungus-growing ants (Attini: Formicidae) engage in an obligate mutualism with fungi they cultivate for food. Although biologists have been fascinated with fungus-growing ants since the resurgence of natural history in the modern era, the early stages of research focused mainly on the foraging beh...

  9. Draft Genome Sequence of the Ant-Associated Fungus Phialophora attae (CBS 131958).

    Science.gov (United States)

    Moreno, Leandro F; Stielow, J Benjamin; de Vries, Michel; Weiss, Vinicius A; Vicente, Vania A; de Hoog, Sybren

    2015-11-19

    The black yeast Phialophora attae was isolated from the cuticle of tropical ant gynes. The ant-fungus association is sustained due to symbiotic evolutionary adaptations that allow fungal assimilation and tolerance of toxic compounds produced by the ant. The genome sequence of the first ant-associated fungus, P. attae, is presented here. Copyright © 2015 Moreno et al.

  10. First localities in Poland of the recently described fungus Cordyceps bifusispora

    Directory of Open Access Journals (Sweden)

    Anna Bujakiewicz

    2014-08-01

    Full Text Available Two localities of the entomopathogenic fungus Cordyceps bifusispora, hitherto not reported from Poland, are characterised by their site conditions and co-occurring macrofungi during the period of the appearance of its stromata. Description of this fungus culture is given and some remarks on the resemblance of its teleomorphs and anamorphs from different collections are discussed.

  11. Mating and Progeny Isolation in The Corn Smut Fungus Ustilago maydis

    Science.gov (United States)

    The corn smut pathogen, Ustilago maydis (U. maydis) (DC.) Corda, is a semi-obligate plant pathogenic fungus in the phylum Basidiomycota (Alexopoulos, Mims and Blackwell, 1996). The fungus can be easily cultured in its haploid yeast phase on common laboratory media. However, to complete its sexual cy...

  12. Differential response by Melaleuca quinquenervia trees to attack by the rust fungus Puccinia psidii in Florida

    Science.gov (United States)

    Melaleuca quinquenervia (melaleuca, paperbark tree) is an exotic invasive tree in Florida, Hawaii, and some Caribbean islands. Puccinia psidii (guava rust-fungus) is a Neotropical rust fungus, reported to attack many species in the Myrtaceae and one genus in the Heteropyxidaceae, both members of the...

  13. BIO-DEINKING OF ONP AND ITS EFFLUENT TREATMENT BY WHITE ROT FUNGUS

    Institute of Scientific and Technical Information of China (English)

    Lu Lin; Chunsheng Pang; Deqing Zhao; Liping Jiang

    2004-01-01

    Deinking of secondary fiber of ONP and effluent treatment with white rot fungus were studied in this paper. Results showed that white rot fungus exerted significant effect on deinking of ONP and CODcr decrease and degradation of pollutants of deinking effluent.

  14. Using copper sulfate to control egg fungus at Keo Fish Farm

    Science.gov (United States)

    Keo Fish Farm is the biggest producer of hybrid striped bass fry in the world. The hatchery manager asked about treatments to control fungus on eggs which occurred fairly often. Our lab has been working on gaining FDA-approval to use copper sulfate to control fungus on catfish eggs, so we were con...

  15. Screening of Fungus Antagonists against Six Main Disease Pathogens in Crops

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    28 soil samples were collected from the rhizosphere of 16 plant species in six different districts in Hunan. As a result of isolation and purification, 122 fungus strains were obtained of which the antagonistic activity was tested against six fungus pathogens in tomato, cotton, cucumber, chilli, rice and rape, and 17 strains were found antagonistic to one or more pathogenic fungi.

  16. Two novel eremophilane sesquiterpenes from an endophytic Xylariaceous fungus isolated from leaves of Cupressus lusitanica

    Energy Technology Data Exchange (ETDEWEB)

    Amaral, Luciana S.; Rodrigues-Filho, Edson, E-mail: edson@dq.ufscar.b [Universidade Federal de Sao Carlos (DQ/UFSCar), SP (Brazil). Dept. de Quimica

    2010-07-01

    Two new eremophilane sesquiterpenes, cupressolide A and cupressolide B, along with two known sesquiterpenes, has been characterized from the EtOAc extract of a liquid medium where a Xylariaceous fungus, isolated as an endophytic fungus from health tissues of Cupressus lusitanica leaves, was cultivated. The structures of the isolated compounds were determined by analyses of their MS and NMR spectroscopic data. (author)

  17. Biotransformation of an africanane sesquiterpene by the fungus Mucor plumbeus.

    Science.gov (United States)

    Fraga, Braulio M; Díaz, Carmen E; Amador, Leonardo J; Reina, Matías; López-Rodriguez, Matías; González-Coloma, Azucena

    2017-03-01

    Biotransformation of 8β-hydroxy-african-4(5)-en-3-one angelate by the fungus Mucor plumbeus afforded as main products 6α,8β-dihydroxy-african-4(5)-en-3-one 8β-angelate and 1α,8β-dihydroxy-african-4(5)-en-3-one 8β-angelate, which had been obtained, together with the substrate, from transformed root cultures of Bethencourtia hermosae. This fact shows that the enzyme system involved in these hydroxylations in both organisms, the fungus and the plant, acts with the same regio- and stereospecificity. In addition another twelve derivatives were isolated in the incubation of the substrate, which were identified as the (2'R,3'R)- and (2'S,3'S)-epoxy derivatives of the substrate and of the 6α- and 1α-hydroxy alcohols, the 8β-(2'R,3'R)- and 8β-(2'S,3'S)-epoxyangelate of 8β,15-dihydroxy-african-4(5)-en-3-one, the hydrolysis product of the substrate, and three isomers of 8β-hydroxy-african-4(5)-en-3-one 2ξ,3ξ-dihydroxy-2-methylbutanoate. The insect antifeedant effects of the pure compounds were tested against chewing and sucking insect species along with their selective cytotoxicity against insect (Sf9) and mammalian (CHO) cell lines.

  18. MORPHOLOGICAL CHARACTERIZATION AND MASS PRODUCTION OF NEMATOPHAGOUS FUNGUS NEMATOCTONUS ROBUSTUS

    Directory of Open Access Journals (Sweden)

    Ramesh babu S,

    2014-06-01

    Full Text Available The plant parasitic nematodes infect the root tissues of the plant causing root galls that lead to reduced water and mineral uptake in the plant root system. Nematophagous fungus are used as biocontrol for the nematodes. Among those Nematoctonus are one of the species used as bioagent. Nematoctonus species produces an extensive mycelium and capture many nematodes with hour glass shaped adhesive knobs on the hyphae. Nematodes become attached to these adhesive knobs and the cuticle of nematode is penetrated by the infective hyphae. This isolate of Nematoctonus robustus is characterized by hyaline mycelium, dikaryotic in nature containing genetically two different nuclei in each cell, having distinct clamp connection. The fungus has better colonizing ability on natural solid substrates like wheat straw and rice straw. It also show good ability to colonize on different cereal grains and various other waste products like coconut coir and FYM etc. This species is one of the best used for mass production and effective for control of plant parasitic nematodes.

  19. Isolation and Identification of Glucoamylase Producer Fungus from Sago Hampas

    Directory of Open Access Journals (Sweden)

    Alfi Asben

    2013-01-01

    Full Text Available Waste of sago processing, notably hampas (ela still contains sago starch is waste that has not been utilized optimally yet  and causing pollution. Isolation and identification of glucoamylase producer fungus of sago hampas waste  were aims to obtain isolates that have gluco-amylolytic properties, and to know glucoamylase activity of selected fungus isolates after grown on artificial medium.  Indegeneous isolates that can produced glucoamylase will be use to get sugar hidrolysate from starch of sago hampas waste for bioetanol production. The study was conducted with the following stages: 1Take the sample from the tennis, 2 Isolation and Identification, 3 Characterization (clear zone, and 4 The production of glucoamylase from selected isolates, The results obtained are: 1 Isolation of fungi gluco-amylolytic from 2 sources sago hampas were produced 10 isolates. Ten isolates were divided into 4 genuses: Gliocladium (as dominant isolate, Aspergilus, Rizhopus and Geotrichum. Isolates of Gliocladium KE gaves the largest degradation of starch on PDA-Starch medium (clear zone, and followed by isolates of Aspergillus GA; 2 Production of glucoamylase on sago hampas with modificated Danial medium (1992 gave the highest activity of Gliocladium KE   on the fifth day of incubation, namely: 10.72 U / mL of crude enzyme   from the supernatant of fermentation substrate (S, and 17.16 U / mL for crude enzyme from the extract of isopropanol isolation (E.

  20. The carbon starvation response of the ectomycorrhizal fungus Paxillus involutus.

    Science.gov (United States)

    Ellström, Magnus; Shah, Firoz; Johansson, Tomas; Ahrén, Dag; Persson, Per; Tunlid, Anders

    2015-04-01

    The amounts of carbon allocated to the fungal partner in ectomycorrhizal associations can vary substantially depending on the plant growth and the soil nutrient conditions, and the fungus may frequently be confronted with limitations in carbon. We used chemical analysis and transcriptome profiling to examine the physiological response of the ectomycorrhizal fungus Paxillus involutus to carbon starvation during axenic cultivation. Carbon starvation induced a decrease in the biomass. Concomitantly, ammonium, cell wall material (chitin) and proteolytic enzymes were released into the medium, which suggest autolysis. Compared with the transcriptome of actively growing hyphae, about 45% of the transcripts analyzed were differentially regulated during C-starvation. Induced during starvation were transcripts encoding extracellular enzymes such as peptidases, chitinases and laccases. In parallel, transcripts of N-transporters were upregulated, which suggest that some of the released nitrogen compounds were re-assimilated by the mycelium. The observed changes suggest that the carbon starvation response in P. involutus is associated with complex cellular changes that involves autolysis, recycling of intracellular compounds by autophagy and reabsorption of the extracellular released material. The study provides molecular markers that can be used to examine the role of autolysis for the turnover and survival of the ectomycorrhizal mycelium in soils.

  1. No sex in fungus-farming ants or their crops.

    Science.gov (United States)

    Himler, Anna G; Caldera, Eric J; Baer, Boris C; Fernández-Marín, Hermógenes; Mueller, Ulrich G

    2009-07-22

    Asexual reproduction imposes evolutionary handicaps on asexual species, rendering them prone to extinction, because asexual reproduction generates novel genotypes and purges deleterious mutations at lower rates than sexual reproduction. Here, we report the first case of complete asexuality in ants, the fungus-growing ant Mycocepurus smithii, where queens reproduce asexually but workers are sterile, which is doubly enigmatic because the clonal colonies of M. smithii also depend on clonal fungi for food. Degenerate female mating anatomy, extensive field and laboratory surveys, and DNA fingerprinting implicate complete asexuality in this widespread ant species. Maternally inherited bacteria (e.g. Wolbachia, Cardinium) and the fungal cultivars can be ruled out as agents inducing asexuality. M. smithii societies of clonal females provide a unique system to test theories of parent-offspring conflict and reproductive policing in social insects. Asexuality of both ant farmer and fungal crop challenges traditional views proposing that sexual farmer ants outpace coevolving sexual crop pathogens, and thus compensate for vulnerabilities of their asexual crops. Either the double asexuality of both farmer and crop may permit the host to fully exploit advantages of asexuality for unknown reasons or frequent switching between crops (symbiont reassociation) generates novel ant-fungus combinations, which may compensate for any evolutionary handicaps of asexuality in M. smithii.

  2. Transformation of Metalaxyl by the Fungus Syncephalastrum racemosum†

    Science.gov (United States)

    Zheng, Zhong; Liu, Shu-Yen; Freyer, Alan J.; Bollag, Jean-Marc

    1989-01-01

    The fungus Syncephalastrum racemosum (Cohn) Schroeter was found to transform the fungicide metalaxyl [N-(2,6-dimethylphenyl)-N-(methoxyacetyl)-alanine methyl ester] in pure culture. After 21 days of incubation in a basal medium amended with 5 μg of metalaxyl per ml, more than 80% of the compound was transformed by the fungus. The transformation rates decreased as the concentrations of metalaxyl increased from 5 to 100 μg/ml. No transformation was observed when the concentration of metalaxyl was higher than 200 μg/ml. Two isomeric metabolites and a mixture of two other isomeric metabolites were isolated from the organic extract of the growth medium and identified as N-(2-methyl-6-hydroxymethylphenyl)-N- and N-(2-hydroxymethyl-6-methylphenyl)-N-(methoxyacetyl)-alanine methyl ester and N-(3-hydroxy- and N-(5-hydroxy-2,6-dimethyl-phenyl)-N-(methoxyacetyl)-alanine methyl ester according to their mass-spectral and nuclear magnetic resonance-spectral characteristics. Benzylic hydroxylation of the methyl side chains and/or aromatic hydroxylation appeared to be the major reactions involved in the metabolism of metalaxyl. PMID:16347836

  3. A novel thermophilic endoglucanase from a mesophilic fungus Fusarium oxysporum

    Institute of Scientific and Technical Information of China (English)

    LIU Shuyan; DUAN Xinyuan; LU Xuemei; GAO Peiji

    2006-01-01

    A novel thermophilic endoglucanase (EGt) was extracted from a mesophilic fungus (Fusarium oxysporum L19). We invoked conventional kinetic enzyme reactions using the sodium salt of carboxymethyl cellulose (CMC-Na) as substrate. EGt displayed optimal activity at 75℃ when kept running 30 min in the temperature range of 30―85℃. Thermal stability curve measured at 70℃ suggested that its half-life time is 15.1 min. The activity was enhanced in the presence of Co2+ or Mg2+ but inhibited by Pb2+ and Fe3+. Moreover, N-bromosuccinimide (NBS) modification resulted in a complete loss of EGt activity, suggesting that tryptophan residues 5 be involved in the enzyme active site. Amino acid composition analysis demonstrated that EGt contains more proline residues. EGt lacks activity towards p-nitrophenyl cellobiose (pNPC). The N-terminal amino acid sequence of EGt is SYRVPAANGFPNP- DASQEKQ, and the gene of EGt was sequenced and analyzed. Extensive sequence alignments failed to show any homology between EGt and any known endoglucanases. This is the first report addressing the thermal adaptation of a cellulolytic enzyme from the mesophilic fungus F. oxysporum. 5be the expression of multiple isoenzyme in an organism helps it adapt to complex living environments.

  4. Modulation of antimicrobial metabolites production by the fungus Aspergillus parasiticus

    Directory of Open Access Journals (Sweden)

    Adriana A.P. Bracarense

    2014-01-01

    Full Text Available Biosynthesis of active secondary metabolites by fungi occurs as a specific response to the different growing environments. Changes in this environment alter the chemical and biological profiles leading to metabolites diversification and consequently to novel pharmacological applications. In this work, it was studied the influence of three parameters (fermentation length, medium composition and aeration in the biosyntheses of antimicrobial metabolites by the fungus Aspergillus parasiticus in 10 distinct fermentation periods. Metabolism modulation in two culturing media, CYA and YES was evaluated by a 2² full factorial planning (ANOVA and on a 2³ factorial planning, role of aeration, medium composition and carbohydrate concentration were also evaluated. In overall, 120 different extracts were prepared, their HPLC profiles were obtained and the antimicrobial activity against A. flavus, C. albicans, E. coli and S. aureus of all extracts was evaluated by microdilution bioassay. Yield of kojic acid, a fine chemical produced by the fungus A. parasiticus was determined in all extracts. Statistical analyses pointed thirteen conditions able to modulate the production of bioactive metabolites by A. parasiticus. Effect of carbon source in metabolites diversification was significant as shown by the changes in the HPLC profiles of the extracts. Most of the extracts presented inhibition rates higher than that of kojic acid as for the extract obtained after 6 days of fermentation in YES medium under stirring. Kojic acid was not the only metabolite responsible for the activity since some highly active extracts showed to possess low amounts of this compound, as determined by HPLC.

  5. One fungus, one name promotes progressive plant pathology.

    Science.gov (United States)

    Wingfield, Michael J; De Beer, Z Wilhelm; Slippers, Bernard; Wingfield, Brenda D; Groenewald, Johannes Z; Lombard, Lorenzo; Crous, Pedro W

    2012-08-01

    The robust and reliable identification of fungi underpins virtually every element of plant pathology, from disease diagnosis to studies of biology, management/control, quarantine and, even more recently, comparative genomics. Most plant diseases are caused by fungi, typically pleomorphic organisms, for which the taxonomy and, in particular, a dual nomenclature system have frustrated and confused practitioners of plant pathology. The emergence of DNA sequencing has revealed cryptic taxa and revolutionized our understanding of relationships in the fungi. The impacts on plant pathology at every level are already immense and will continue to grow rapidly as new DNA sequencing technologies continue to emerge. DNA sequence comparisons, used to resolve a dual nomenclature problem for the first time only 19 years ago, have made it possible to approach a natural classification for the fungi and to abandon the confusing dual nomenclature system. The journey to a one fungus, one name taxonomic reality has been long and arduous, but its time has come. This will inevitably have a positive impact on plant pathology, plant pathologists and future students of this hugely important discipline on which the world depends for food security and plant health in general. This contemporary review highlights the problems of a dual nomenclature, especially its impact on plant pathogenic fungi, and charts the road to a one fungus, one name system that is rapidly drawing near. © 2011 The Authors. Molecular Plant Pathology © 2011 BSPP and Blackwell Publishing Ltd.

  6. The response of filamentous fungus Rhizopus nigricans to flavonoids.

    Science.gov (United States)

    Slana, Marko; Zigon, Dušan; Makovec, Tomaž; Lenasi, Helena

    2011-08-01

    The saprophytic fungus Rhizopus nigricans constitutes a serious problem when thriving on gathered crops. The identification of any compounds, especially natural ones, that inhibit fungal growth, may therefore be important. During its life cycle, Rhizopus nigricans encounters many compounds, among them the flavonoids, plant secondary metabolites that are involved in plant defense against pathogenic microorganisms. Although not being a plant pathogen, Rhizopus nigricans may interact with these compounds in the same way as plant pathogens--in response to the fungitoxic effect of flavonoids the fungi transform them into less toxic metabolites. We have studied the interaction of R. nigricans with some flavonoids. Inhibition of hyphal spreading (from 3% to 100%) was observed by 300 μM flavones, flavanones and isoflavones, irrespective of their basic structure, oxidized or reduced C-ring, and orientation of the B-ring. However, a hydrophobic A-ring was important for the toxicity. R. nigricans transformed some of the flavonoids into glucosylated products. Recognition of substrates for glucosylating enzyme(s) did not correlate with their fungitoxic effect but depended exclusively on the presence of a free -OH group in the flavonoid A-ring and of a hydrophobic B-ring. Although the fungus produced glucosyltransferase constitutively, an additional amount of the enzyme was induced by the substrate flavonoid. Moreover, effective detoxification was shown to require the presence of glucose.

  7. Effect and influence factors of sulfur removal in coal with fungus

    Institute of Scientific and Technical Information of China (English)

    HE De-wen; JIN Yan; CHAI Li-yuan; HUANG Rui; PENG Bing; WANG Yun-yan

    2005-01-01

    The influence of coal desulfurization by fungus was experimentally studied. The results suggest that fungus can effectively remove inorganic and organic sulfur in coal, and main influences of desulfurization by fungus of pH value, temperature, coal slurry concentration and coal granularity were studied by orthodox experiment and the optimal experimental conditions are′as follows: pH value 6, temperature 45 ℃, coal slurry concentration 10% and coal granularity 100 μm. Under above conditions, fungus car remove up to 44.96% total sulfur and 54. 87% inorganic sulfur within two days, and their desulfurization rates will increase along with time. Compared with sulfolobas, desulphurization by fungus is steady and more effective, and has advantage of high speed.

  8. Accumulation and chemical states of radiocesium by fungus Saccharomyces cerevisiae

    Science.gov (United States)

    Ohnuki, Toshihiko; Sakamoto, Fuminori; Kozai, Naofumi; Yamasaki, Shinya; Yu, Qianqian

    2014-05-01

    After accident of Fukushima Daiichi Nuclear Power Plant, the fall-out radiocesium was deposited on the ground. Filamentous fungus is known to accumulate radiocesium in environment, even though many minerals are involved in soil. These facts suggest that fungus affect the migration behavior of radiocesium in the environment. However, accumulation mechanism of radiocesium by fungus is not understood. In the present study, accumulation and chemical states change of Cs by unicellular fungus of Saccharomyces cerevisiae have been studied to elucidate the role of microorganisms in the migration of radiocesium in the environment. Two different experimental conditions were employed; one is the accumulation experiments of radiocesium by S. cerevisiae from the agar medium containing 137Cs and a mineral of zeolite, vermiculite, smectite, mica, or illite. The other is the experiments using stable cesium to examine the chemical states change of Cs. In the former experiment, the cells were grown on membrane filter of 0.45 μm installed on the agar medium. After the grown cells were weighed, radioactivity in the cells was measured by an autoradiography technique. The mineral weight contents were changed from 0.1% to 1% of the medium. In the latter experiment, the cells were grown in the medium containing stable Cs between 1 mM and 10mM. The Cs accumulated cells were analyzed by SEM-EDS and EXAFS. The adsorption experiments of cesium by the cells under resting condition were also conducted to test the effect of cells metabolic activity. Without mineral in the medium, cells of S. cerevisiae accumulated 1.5x103 Bq/g from the medium containing 137Cs of 2.6x102 Bq/g. When mineral was added in the medium, concentration of 137Cs in the cells decreased. The concentration of 137Cs in the cells from the medium containing different minerals were in the following order; smectite, illite, mica > vermiculite > zeolite. This order was nearly the same as the inverse of distribution coefficient of

  9. Evidence refuting the contribution of the fungus Aspergillus penicillioides to the allergenicity of the house dust mite Dermatophagoides pteronyssinus.

    Science.gov (United States)

    Hay, D B; Hart, B J; Douglas, A E

    1992-01-01

    This communication demonstrates unequivocally that the fungi associated with house dust mites do not contribute to mite allergenicity. The evidence is twofold: first, larval mites which lack fungi have allergen profiles indistinguishable from fungus-bearing adult mites. Second, the allergen profile of experimentally-derived fungus-free adult mites and mites re-fed the fungus Aspergillus penicillioides are identical.

  10. Identification of rice blast fungal elicitor-responsive genes by differential display analysis.

    Science.gov (United States)

    Kim, C Y; Lee, S H; Park, H C; Bae, C G; Cheong, Y H; Choi, Y J; Han, C; Lee, S Y; Lim, C O; Cho, M J

    2000-04-01

    In order to study molecular interactions that occur between rice and rice blast fungus upon infection, we isolated fungal elicitor-responsive genes from rice (Oryza sativa cv. Milyang 117) suspension-cultured cells treated with fungal elicitor prepared from the rice blast fungus (Magnaporthe grisea) employing a method that combined mRNA differential display and cDNA library screening. Data base searches with the isolated cDNA clones revealed that the OsERG1 and OsERG2 cDNAs share significant similarities with the mammalian Ca2+-dependent lipid binding (C2) domains. The OsCPX1 cDNA is highly homologous to peroxidases. The OsHin1 cDNA exhibits homology to the tobacco hin1 gene, whose expression is induced by avirulent pathogens. The OsLPL1 and OsMEK1 cDNAs share homologies with lysophospholipases and serine/threonine mitogen-activated protein (MAP) kinase kinases, respectively. The OsWRKY1 and OsEREBP1 cDNAs are homologous to transcription factors, such as the WRKY protein family and the AP2/EREBP family, respectively. Transcripts of the OsERG1, OsHin1, and OsMEK1 genes were specifically elevated only in response to the avirulent race KJ301 of the rice blast fungus. Our study yielded a number of elicitor-responsive genes that will not only provide molecular probes, but also contribute to our understanding of host defense mechanisms against the rice blast fungus.

  11. Towards an integrated understanding of the consequences of fungus domestication on the fungus-growing termite gut microbiota

    DEFF Research Database (Denmark)

    Thomas-Poulsen, Michael

    2015-01-01

    Approximately 30 million years ago (MYA), the subfamily of higher termites Macrotermitinae domesticated a fungus, Termitomyces, as the main plant decomposer and food source for the termite host. The origin of fungiculture shifted the composition of the termite gut microbiota, and some of the func......Approximately 30 million years ago (MYA), the subfamily of higher termites Macrotermitinae domesticated a fungus, Termitomyces, as the main plant decomposer and food source for the termite host. The origin of fungiculture shifted the composition of the termite gut microbiota, and some...... of the functional implications of this shift have recently been established. I review reports on the composition of the Macrotermitinae gut microbiota, evidence for a subfamily core gut microbiota, and the first insight into functional complementarity between fungal and gut symbionts. In addition, I argue that we...... need to explore the capacities of all members of the symbiotic communities, including better solidifying Termitomyces role(s) in order to understand putative complementary gut bacterial contributions. Approaches that integrate natural history and sequencing data to elucidate symbiont functions...

  12. Quantitative proteomic analysis of the response of the wood-rot fungus, Schizophyllum commune, to the biocontrol fungus, Trichoderma viride.

    Science.gov (United States)

    Ujor, V C; Peiris, D G; Monti, M; Kang, A S; Clements, M O; Hedger, J N

    2012-04-01

    Investigation of changes in the protein profile of the wood-rot fungus, Schizophyllum commune, when paired against the biocontrol fungus, Trichoderma viride, for 48 h. Variations in protein profile resulting from contact with T. viride were assessed by spot separation using 2 dimensional protein gel electrophoresis followed by MALDI-TOF-TOF MS/MS protein identification. Contact with T. viride elicited a systematic response in S. commune, characterized by marked increases in proteins involved for transcription and translation (61%) and cell wall/hyphal biogenesis and stabilization (17%), whereas metabolism-associated proteins decreased in amounts (64%). Trichoderma viride, however, exhibited typical mycoparasitic behaviour with increases in the amounts of proteins involved in proteolysis and carbohydrate metabolism. The protein profile of S. commune confronted by T. viride indicates the up-regulation of mechanisms specifically targeted at the mycoparasitic machinery of T. viride, particularly cell wall lysis and antibiosis. The proteomic responses observed in S. commune may occur in natural environments, providing an insight to the mechanism involved in conferring resistance to mycoparasitic attack. This study, therefore, warrants further investigation for the targeted design of more robust biocontrol agents. © 2012 The Authors. Letters in Applied Microbiology © 2012 The Society for Applied Microbiology.

  13. The crucial role of the Pls1 tetraspanin during ascospore germination in Podospora anserina provides an example of the convergent evolution of morphogenetic processes in fungal plant pathogens and saprobes.

    Science.gov (United States)

    Lambou, Karine; Malagnac, Fabienne; Barbisan, Crystel; Tharreau, Didier; Lebrun, Marc-Henri; Silar, Philippe

    2008-10-01

    Pls1 tetraspanins were shown for some pathogenic fungi to be essential for appressorium-mediated penetration into their host plants. We show here that Podospora anserina, a saprobic fungus lacking appressorium, contains PaPls1, a gene orthologous to known PLS1 genes. Inactivation of PaPls1 demonstrates that this gene is specifically required for the germination of ascospores in P. anserina. These ascospores are heavily melanized cells that germinate under inducing conditions through a specific pore. On the contrary, MgPLS1, which fully complements a DeltaPaPls1 ascospore germination defect, has no role in the germination of Magnaporthe grisea nonmelanized ascospores but is required for the formation of the penetration peg at the pore of its melanized appressorium. P. anserina mutants with mutation of PaNox2, which encodes the NADPH oxidase of the NOX2 family, display the same ascospore-specific germination defect as the DeltaPaPls1 mutant. Both mutant phenotypes are suppressed by the inhibition of melanin biosynthesis, suggesting that they are involved in the same cellular process required for the germination of P. anserina melanized ascospores. The analysis of the distribution of PLS1 and NOX2 genes in fungal genomes shows that they are either both present or both absent. These results indicate that the germination of P. anserina ascospores and the formation of the M. grisea appressorium penetration peg use the same molecular machinery that includes Pls1 and Nox2. This machinery is specifically required for the emergence of polarized hyphae from reinforced structures such as appressoria and ascospores. Its recurrent recruitment during fungal evolution may account for some of the morphogenetic convergence observed in fungi.

  14. Constitutive expression of pathogen-inducible OsWRKY31 enhances disease resistance and affects root growth and auxin response in transgenic rice plants

    Institute of Scientific and Technical Information of China (English)

    Juan Zhang; Youliang Peng; Zejian Guo

    2008-01-01

    WRKY transcription factors have many regulatory roles in response to biotic and abiotic stresses. In this study, we isolated a rice WRKY gene (OsWRKY31) that is induced by the rice blast fungus Magnaporthe grisea and auxin. This gene encodes a polypeptide of 211 amino-acid residues and belongs to a subgroup of the rice WRKY gene family that probably originated after the divergence of monocot and dicot plants. OsWRKY31 was found to be localized to the nucleus of onion epidermis cells to transiently express OsWRKY31-eGFP fusion protein. Analysis of 0sWRKY31 and its mutants fused with a Cal4 DNA-binding domain indicated that OsWRKY31 has transactivation activity in yeast. Overexpression of the OsWRKY31 gene was found to enhance resistance against infection with M. grisea, and the transgenic lines exhibited reduced lateral root formation and elongation compared with wild-type and RNAi plants. The lines with overexpression showed constitutive expression of many defense-related genes, such as PBZ1 and OsSci2, as well as early auxin-response genes, such as OsIAA4 and OsCrll genes. Furthermore, the plants with overexpression were less sensitive to exogenously supplied IBA, NAA and 2,4-D at high concentrations, suggesting that overexpression of the OsWRKY31 gene might alter the auxin response or transport. These results also suggest that OsWRKY31 might be a common component in the signal transduction pathways of the auxin response and the defense response in rice.

  15. Rice transformation with cell wall degrading enzyme genes from Trichoderma atroviride and its effect on plant growth and resistance to fungal pathogens

    Institute of Scientific and Technical Information of China (English)

    Liu Mei; Sun Zong-Xiu; Zhu Jie; Xu Tong; Gary E Harman; Matteo Lorito; Sheri Woo

    2004-01-01

    @@ Three genes encoding for fungal cell wall degrading enzymes (CWDE), ech42, nag70 and gluc78from the biocontrol fungus Trichoderma atroviride were inserted into the binary vector pCAMBIA1305. 2 singly and in all possible combinations. The coding sequences were placed downstream of the rice actin promoter and all vectors were used to transform rice plants. A total of more than 1,800 independently regenerated plantlets in seven different populations (for each of the three genes and each of the four gene combinations) were obtained. Expression in plant was obtained for all the fungal genes used singly or in combinations. The ech42 gene encoding for an endochitinase increased resistance to sheath blight caused by Rhizoctonia solani, while the exochitinase-encoding gene, nag70, had a lesser effect. The expression level of endochitinase but not of the exochitinase was correlated with disease resistance. Nevertheless, exochitinase enhanced the positive effect of endochitinase on disease resistance when two genes were co-expressed in transgenic rice. Improved resistance to Magnaporthe grisea was found in all types of regenerated plants, including those with the gluc78 gene alone, while a few lines expressing either ech42 or nag70 appeared to be immune to this pathogen. Transgenic plants expressing the gluc78 gene alone were stunted and only few of them survived, even though they showed resistance to M. grisea. However, combination with either one of the two other genes ( ech42, nag70 ) as included in the same T-DNA region, reduced the negative effect of gluc78 on plant growth. This is the first report of single or multiple of expression of transgens encoding CWDEs that results in resistance to blast and sheath blight in rice.

  16. Directed evolution of a filamentous fungus for thermotolerance

    Directory of Open Access Journals (Sweden)

    Lyons Thomas J

    2009-08-01

    Full Text Available Abstract Background Filamentous fungi are the most widely used eukaryotic biocatalysts in industrial and chemical applications. Consequently, there is tremendous interest in methodology that can use the power of genetics to develop strains with improved performance. For example, Metarhizium anisopliae is a broad host range entomopathogenic fungus currently under intensive investigation as a biologically based alternative to chemical pesticides. However, it use is limited by the relatively low tolerance of this species to abiotic stresses such as heat, with most strains displaying little to no growth between 35–37°C. In this study, we used a newly developed automated continuous culture method called the Evolugator™, which takes advantage of a natural selection-adaptation strategy, to select for thermotolerant variants of M. anisopliae strain 2575 displaying robust growth at 37°C. Results Over a 4 month time course, 22 cycles of growth and dilution were used to select 2 thermotolerant variants of M. anisopliae. Both variants displayed robust growth at 36.5°C, whereas only one was able to grow at 37°C. Insect bioassays using Melanoplus sanguinipes (grasshoppers were also performed to determine if thermotolerant variants of M. anisopliae retained entomopathogenicity. Assays confirmed that thermotolerant variants were, indeed, entomopathogenic, albeit with complex alterations in virulence parameters such as lethal dose responses (LD50 and median survival times (ST50. Conclusion We report the experimental evolution of a filamentous fungus via the novel application of a powerful new continuous culture device. This is the first example of using continuous culture to select for complex phenotypes such as thermotolerance. Temperature adapted variants of the insect-pathogenic, filamentous fungus M. anisopliae were isolated and demonstrated to show vigorous growth at a temperature that is inhibitory for the parent strain. Insect virulence assays

  17. Protein profiling of the dimorphic, pathogenic fungus, Penicillium marneffei

    Directory of Open Access Journals (Sweden)

    Rundle William T

    2008-06-01

    Full Text Available Abstract Background Penicillium marneffei is a pathogenic fungus that afflicts immunocompromised individuals having lived or traveled in Southeast Asia. This species is unique in that it is the only dimorphic member of the genus. Dimorphism results from a process, termed phase transition, which is regulated by temperature of incubation. At room temperature, the fungus grows filamentously (mould phase, but at body temperature (37°C, a uninucleate yeast form develops that reproduces by fission. Formation of the yeast phase appears to be a requisite for pathogenicity. To date, no genes have been identified in P. marneffei that strictly induce mould-to-yeast phase conversion. In an effort to help identify potential gene products associated with morphogenesis, protein profiles were generated from the yeast and mould phases of P. marneffei. Results Whole cell proteins from the early stages of mould and yeast development in P. marneffei were resolved by two-dimensional gel electrophoresis. Selected proteins were recovered and sequenced by capillary-liquid chromatography-nanospray tandem mass spectrometry. Putative identifications were derived by searching available databases for homologous fungal sequences. Proteins found common to both mould and yeast phases included the signal transduction proteins cyclophilin and a RACK1-like ortholog, as well as those related to general metabolism, energy production, and protection from oxygen radicals. Many of the mould-specific proteins identified possessed similar functions. By comparison, proteins exhibiting increased expression during development of the parasitic yeast phase comprised those involved in heat-shock responses, general metabolism, and cell-wall biosynthesis, as well as a small GTPase that regulates nuclear membrane transport and mitotic processes in fungi. The cognate gene encoding the latter protein, designated RanA, was subsequently cloned and characterized. The P. marneffei RanA protein

  18. A role for antioxidants in acclimation of marine derived pathogenic fungus (NIOCC 1) to salt stress.

    Science.gov (United States)

    Ravindran, Chinnarajan; Varatharajan, Govindaswamy R; Rajasabapathy, Raju; Vijayakanth, S; Kumar, Alagu Harish; Meena, Ram M

    2012-09-01

    Salinity tolerance a key factor helps in understanding the ionic homeostasis in general, which is a fundamental cellular phenomenon in all living cells. Here, a marine derived pathogenic fungus was examined for its adaptation under salt stress using antioxidant properties. The aqueous extracts of halophilic fungus exhibited different levels of antioxidant activity in all the in vitro tests such as α,α-diphenyl-β-picrylhydrazyl (DPPH(·)), Hydroxyl Radical Scavenging Assay (HRSA), Metal chelating assay and β-carotene-linoleic acid model system. The antioxidant capacity of marine fungus exposed to high salt condition showed an increase in activity. In addition, the production of intra and extracellular antioxidant enzymes of the fungus at various salt stresses were analyzed and discussed for their possible role in the stress mechanism. The marine derived fungus was identified as Phialosimplex genus, which is associated with infections in dogs. Thus the present study elucidates that the scavenging activity is one of the protective mechanisms developed in the fungus to avoid the deleterious effect of salt stress. In addition, the study also helps in understanding how the pathogenic fungus tackles the oxidative burst i.e. hypersensitivity reaction performed by host to kill the pathogens.

  19. Biosorption of cadmium using the fungus Aspergillus niger

    Directory of Open Access Journals (Sweden)

    L.M. Barros Júnior

    2003-09-01

    Full Text Available Sorption experiments using the Aspergillus niger fungus for cadmium removal were carried out to study the factors influencing and optimizing the biosorption of this metal. The effects of pH, time, biomass concentration, and initial concentration of the heavy metal on the rate of metallic biosorption were examined. An experimental design was also used to determine the values of the under study variables that provided the greatest biosorption efficiency. A technique for biomass recovery was also developed with the objective of determining the capacity of the regenerated biomass to biosorb the metals in solution. This research proved that with a pH of 4.75, a biomass concentration of 0.7 g/L, and a heavy metal concentration varying between 5 and 10 mg/L a biosorption process of biosorption with Aspergillus niger could be successfully used for heavy metal removal from oil field water in the oil industry.

  20. Two new triterpenoids from fruiting bodies of fungus Ganoderma lucidum.

    Science.gov (United States)

    Zhao, Zhen-Zhu; Yin, Rong-Hua; Chen, He-Ping; Feng, Tao; Li, Zheng-Hui; Dong, Ze-Jun; Cui, Bao-Kai; Liu, Ji-Kai

    2015-01-01

    Two new triterpenoids, (24E)-9α,11α-epoxy-3β-hydroxylanosta-7,24-dien-26-al (1) and (22Z,24Z)-13-hydroxy-3-oxo-14(13 → 12)abeo-lanosta-8,22,24-trien-26,23-olide (2) were isolated from dried fruiting bodies of fungus Ganoderma lucidum. The structures of these two new compounds were elucidated on the basis of extensive spectroscopic analyses. Compound 1 possessed a lanostane skeleton, while compound 2 was based on a rare 14 (13 → 12)abeo-lanostane skeleton with a 26,23-olide moiety. Both of them were evaluated for their antifungal and cytotoxic activities. Neither of them displayed obvious inhibition on Candida albicans and five human cancer cell lines.

  1. Amphibian chytrid fungus Batrachochytrium dendrobatidis in Cusuco National Park, Honduras.

    Science.gov (United States)

    Kolby, Jonathan E; Padgett-Flohr, Gretchen E; Field, Richard

    2010-11-01

    Amphibian population declines in Honduras have long been attributed to habitat degradation and pollution, but an increasing number of declines are now being observed from within the boundaries of national parks in pristine montane environments. The amphibian chytrid fungus Batrachochytrium dendrobatidis has been implicated in these declines and was recently documented in Honduras from samples collected in Pico Bonito National Park in 2003. This report now confirms Cusuco National Park, a protected cloud forest reserve with reported amphibian declines, to be the second known site of infection for Honduras. B. dendrobatidis infection was detected in 5 amphibian species: Craugastor rostralis, Duellmanohyla soralia, Lithobates maculata, Plectrohyla dasypus, and Ptychohyla hypomykter. D. soralia, P. dasypus, and P. hypomykter are listed as critically endangered in the IUCN Red List of Threatened Species and have severely fragmented or restricted distributions. Further investigations are necessary to determine whether observed infection levels indicate an active B. dendrobatidis epizootic with the potential to cause further population declines and extinction.

  2. Molecular Mechanisms Regulating Sporulation in the Filamentous Fungus Ashbya gossypii

    DEFF Research Database (Denmark)

    Wasserstrom, Lisa

    Sporulation is a complex developmental program that fungi enter to ensure survival in unfavorable environmental conditions. Many fungal species are able to produce spores sexually through meiosis, which is beneficial since it introduces genetic variability into a population. The sexually reproduc......Sporulation is a complex developmental program that fungi enter to ensure survival in unfavorable environmental conditions. Many fungal species are able to produce spores sexually through meiosis, which is beneficial since it introduces genetic variability into a population. The sexually......, which is regulated by the pheromone response pathway. Most ascomycetes have been reported to produce meiotic spores, however, a sexual cycle has not yet been identified in the filamentous fungus Ashbya gossypii. The main focus of my doctoral thesis has therefore been to understand the mechanisms behind...

  3. Polyketides from the Halotolerant Fungus Myrothecium sp. GS-17

    Directory of Open Access Journals (Sweden)

    Tao Liu

    2013-12-01

    Full Text Available Two new polyketides, myrothecol (1 and 5-hydroxy-3-methyl-4-(1- hydroxylethyl-furan-2(5H-one (2, were isolated from the fermentation broth of the halotolerant fungus Myrothecium sp. GS-17 along with three known compounds, 5-hydroxyl-3-[(1S-1-hydroxyethyl]-4-methylfuran-2(5H-one (3, 3,5-dimethyl-4- hydroxylmethyl-5-methoxyfuran-2(5H-one (4, and 3,5-dimethyl-4-hydroxymethyl-5- hydroxyfuran-2(5H-one (5. Compound 1 is the first natural occurring polyketide with a unique furylisobenzofuran skeleton. The structures of these compounds were established via extensive spectroscopic analyses including 1D-, 2D-NMR, HRESI-MS, and crystal X-ray diffraction analysis.

  4. New Bergamotane Sesquiterpenoids from the Plant Endophytic Fungus Paraconiothyrium brasiliense

    Directory of Open Access Journals (Sweden)

    Zhe Guo

    2015-08-01

    Full Text Available Brasilamides K-N (1–4, four new bergamotane sesquiterpenoids; with 4-oxatricyclo (3.3.1.0 2,7nonane (1and 9-oxatricyclo(4.3.0.0 4,7nonane (2–4 skeletons; were isolated from the scale-up fermentation cultures of the plant endophytic fungus Paraconiothynium brasiliense Verkley. The previously identified sesquiterpenoids brasilamides A and C (5 and 6 were also reisolated in the current work. The structures of 1–4 were elucidated primarily by interpretation of NMR spectroscopic data. The absolute configurations of 1–3 were deduced by analogy to the co-isolated metabolites 5 and 6; whereas that of C-12 in 4 was assigned using the modified Mosher method. The cytotoxicity of all compounds against a panel of eight human tumor cell lines were assayed.

  5. Molecular Karyotype of the White Rot Fungus Pleurotus ostreatus

    Science.gov (United States)

    Larraya, Luis M.; Pérez, Gumer; Peñas, María M.; Baars, Johan J. P.; Mikosch, Thomas S. P.; Pisabarro, Antonio G.; Ramírez, Lucía

    1999-01-01

    The white rot fungus Pleurotus ostreatus is an edible basidiomycete with increasing agricultural and biotechnological importance. Genetic manipulation and breeding of this organism are restricted because of the lack of knowledge about its genomic structure. In this study, we analyzed the genomic constitution of P. ostreatus by using pulsed-field gel electrophoresis optimized for the separation of its chromosomes. We have determined that it contains 11 pairs of chromosomes with sizes ranging from 1.4 to 4.7 Mbp. In addition to chromosome separation, the use of single-copy DNA probes allowed us to resolve the ambiguities caused by chromosome comigration. When the two nuclei present in the dikaryon were separated by protoplasting, analysis of their karyotypes revealed length polymorphisms affecting various chromosomes. This is, to our knowledge, the clearest chromosome separation available for this species. PMID:10427028

  6. The invasive chytrid fungus of amphibians paralyzes lymphocyte responses.

    Science.gov (United States)

    Fites, J Scott; Ramsey, Jeremy P; Holden, Whitney M; Collier, Sarah P; Sutherland, Danica M; Reinert, Laura K; Gayek, A Sophia; Dermody, Terence S; Aune, Thomas M; Oswald-Richter, Kyra; Rollins-Smith, Louise A

    2013-10-18

    The chytrid fungus, Batrachochytrium dendrobatidis, causes chytridiomycosis and is a major contributor to global amphibian declines. Although amphibians have robust immune defenses, clearance of this pathogen is impaired. Because inhibition of host immunity is a common survival strategy of pathogenic fungi, we hypothesized that B. dendrobatidis evades clearance by inhibiting immune functions. We found that B. dendrobatidis cells and supernatants impaired lymphocyte proliferation and induced apoptosis; however, fungal recognition and phagocytosis by macrophages and neutrophils was not impaired. Fungal inhibitory factors were resistant to heat, acid, and protease. Their production was absent in zoospores and reduced by nikkomycin Z, suggesting that they may be components of the cell wall. Evasion of host immunity may explain why this pathogen has devastated amphibian populations worldwide.

  7. Fungal keratitis due to Schizophyllum commune: an emerging pathogenic fungus.

    Science.gov (United States)

    Reddy, Ashok Kumar; Ashok, Rangaiahgari; Majety, Madhavi; Chitta, Megharaj; Narayen, Nitesh

    2016-07-12

    Fungal keratitis due to Schizophyllum commune is very rare. In this study, we report the clinical and microbiological profile of five patients with fungal keratitis due to S. commune. Direct microscopic examination of corneal scrapings from all five patients showed septate branching hyaline fungal filaments. Similarly, in all five patients Sabouraud dextrose agar (SDA) plates inoculated with corneal scrapings showed white, cottony colonies on the second day of incubation. Lactophenol cotton blue stained wet preparation of 7-day-old colonies on SDA revealed clamp connections and no spores. The fungus was identified by its characteristic clamp connections, fan-shaped bracket fruiting body with pinkish-grey longitudinally split-radiating gills. The phenotypic identification of one of the five isolates further conformed by ITS sequencing. Treatment outcome was available for two of the five patients; in these two patients, the keratitis resolved with topical natamycin. © 2016 Blackwell Verlag GmbH.

  8. Garden sharing and garden stealing in fungus-growing ants

    Science.gov (United States)

    Adams, Rachelle M. M.; Mueller, U. G.; Holloway, Alisha K.; Green, Abigail M.; Narozniak, Joanie

    Fungi cultivated by fungus-growing ants (Attini: Formicidae) are passed on between generations by transfer from maternal to offspring nest (vertical transmission within ant species). However, recent phylogenetic analyses revealed that cultivars are occasionally also transferred between attine species. The reasons for such lateral cultivar transfers are unknown. To investigate whether garden loss may induce ants to obtain a replacement cultivar from a neighboring colony (lateral cultivar transfer), pairs of queenright colonies of two Cyphomyrmex species were set up in two conjoined chambers; the garden of one colony was then removed to simulate the total crop loss that occurs naturally when pathogens devastate gardens. Garden-deprived colonies regained cultivars through one of three mechanisms: joining of a neighboring colony and cooperation in a common garden; stealing of a neighbor's garden; or aggressive usurpation of a neighbor's garden. Because pathogens frequently devastate attine gardens under natural conditions, garden joining, stealing and usurpation emerge as critical behavioral adaptations to survive garden catastrophes.

  9. Antimicrobial Aromatic Polyketides from Gorgonian- Associated Fungus, Penicillium commune 518

    Institute of Scientific and Technical Information of China (English)

    王俊锋; 刘培培; 王义; 王慧; 李静; 庄以彬; 朱伟明

    2012-01-01

    Seven new aromatic polyketides, communols A-G (1-7), were isolated and identified from the fermentation broth of Penicillium commune 518, a marine-derived fungus associated with the Gorgonian, Muricella abnormalis. The new structures of 1-7 were determined by spectroscopic analysis and X-ray single crystal diffraction. Among them, communol D (4) was the first example of a naturally occurring aromatic polyketide with a sulfoxide group from marine thngi. Compounds 1, 6, and 7 all showed moderate antimicrobial activities against Escherichia coli and Enterobacter aerogenes with MIC values of 4.1/16.4, 6.4/25.8, and 23.8/23.8μmoloL^-1, respectively.

  10. Callistosporium pinicola (Basidiomycota, a fungus species new to Poland

    Directory of Open Access Journals (Sweden)

    Marek Halama

    2014-09-01

    Full Text Available Basidiomata of Callistosporium pinicola were collected in years 2012–2013, on strongly decayed fallen trunks of Picea abies and Abies alba on two remote sites, localized in North-eastern and southern Poland. These localities represent the first records of this fungus in Poland. A full description and illustration of C. pinicola based on Polish specimens are provided and the distinguishing features and delimitation of the species are briefly discussed. The ecology of C. pinicola, its general distribution and threat are also presented. As all specimens of C. pinicola were collected only in recent years we suggest that this species is increasing its distribution in Poland. However, we cannot rule out the possibility that, because of its cryptic nature, C. pinicola has been much overlooked in the past.

  11. Enzymes and bioproducts produced by the ascomycete fungus Paecilomyces variotii.

    Science.gov (United States)

    Herrera Bravo de Laguna, I; Toledo Marante, F J; Mioso, R

    2015-12-01

    Due its innate ability to produce extracellular enzymes which can provide eco-friendly solutions for a variety of biotechnological applications, Paecilomyces variotii is a potential source of industrial bioproducts. In this review, we report biotechnological records on the biochemistry of different enzymes produced by the fermentation of the P. variotii fungus, including tannases, phytases, cellulases, xylanases, chitinases, amylases and pectinases. Additionally, the main physicochemical properties which can affect the enzymatic reactions of the enzymes involved in the conversion of a huge number of substrates to high-value bioproducts are described. Despite all the background information compiled in this review, more research is required to consolidate the catalytic efficiency of P. variotii, which must be optimized so that it is more accurate and reproducible on a large scale.

  12. A new diketopiperazine heterodimer from an endophytic fungus Aspergillus niger.

    Science.gov (United States)

    Li, Xiao-Bin; Li, Yue-Lan; Zhou, Jin-Chuan; Yuan, Hui-Qing; Wang, Xiao-Ning; Lou, Hong-Xiang

    2015-01-01

    One new diketopiperazine heterodimer, asperazine A (1), and eight known compounds, asperazine (2), cyclo(d-Phe-l-Trp) (3), cyclo(l-Trp-l-Trp) (4), 4-(hydroxymethyl)-5,6-dihydro-pyran-2-one (5), walterolactone A (6), and campyrones A-C (7-9), were isolated from an endophytic fungus Aspergillus niger. Their structures were determined unequivocally on the basis of extensive spectroscopic data analysis. This is the first report of the presence of compound 3 as a natural product. Cytotoxicity test against human cancer cell lines PC3, A2780, K562, MBA-MD-231, and NCI-H1688 revealed that compounds 1 and 2 had weak activities.

  13. Disposable diapers biodegradation by the fungus Pleurotus ostreatus.

    Science.gov (United States)

    Espinosa-Valdemar, Rosa María; Turpin-Marion, Sylvie; Delfín-Alcalá, Irma; Vázquez-Morillas, Alethia

    2011-08-01

    This research assesses the feasibility of degrading used disposable diapers, an important component (5-15% in weight) of urban solid waste in Mexico, by the activity of the fungus Pleurotus ostreatus, also known as oyster mushroom. Disposable diapers contain polyethylene, polypropylene and a super absorbent polymer. Nevertheless, its main component is cellulose, which degrades slowly. P. ostreatus has been utilized extensively to degrade cellulosic materials of agroindustrial sources, using in situ techniques. The practice has been extended to the commercial farming of the mushroom. This degradation capacity was assayed to reduce mass and volume of used disposable diapers. Pilot laboratory assays were performed to estimate the usefulness of the following variables on conditioning of used diapers before they act as substrate for P. ostreatus: (1) permanence vs removal of plastic cover; (2) shredding vs grinding; (3) addition of grape wastes to improve structure, nitrogen and trace elements content. Wheat straw was used as a positive control. After 68 days, decrease of the mass of diapers and productivity of fungus was measured. Weight and volume of degradable materials was reduced up to 90%. Cellulose content was diminished in 50% and lignine content in 47%. The highest efficiency for degradation of cellulosic materials corresponded to the substrates that showed highest biological efficiency, which varied from 0% to 34%. Harvested mushrooms had good appearance and protein content and were free of human disease pathogens. This research indicates that growing P. ostreatus on disposable diapers could be a good alternative for two current problems: reduction of urban solid waste and availability of high protein food sources.

  14. Chemically armed mercenary ants protect fungus-farming societies.

    Science.gov (United States)

    Adams, Rachelle M M; Liberti, Joanito; Illum, Anders A; Jones, Tappey H; Nash, David R; Boomsma, Jacobus J

    2013-09-24

    The ants are extraordinary in having evolved many lineages that exploit closely related ant societies as social parasites, but social parasitism by distantly related ants is rare. Here we document the interaction dynamics among a Sericomyrmex fungus-growing ant host, a permanently associated parasitic guest ant of the genus Megalomyrmex, and a raiding agro-predator of the genus Gnamptogenys. We show experimentally that the guest ants protect their host colonies against agro-predator raids using alkaloid venom that is much more potent than the biting defenses of the host ants. Relatively few guest ants are sufficient to kill raiders that invariably exterminate host nests without a cohabiting guest ant colony. We also show that the odor of guest ants discourages raider scouts from recruiting nestmates to host colonies. Our results imply that Sericomyrmex fungus-growers obtain a net benefit from their costly guest ants behaving as a functional soldier caste to meet lethal threats from agro-predator raiders. The fundamentally different life histories of the agro-predators and guest ants appear to facilitate their coexistence in a negative frequency-dependent manner. Because a guest ant colony is committed for life to a single host colony, the guests would harm their own interests by not defending the host that they continue to exploit. This conditional mutualism is analogous to chronic sickle cell anemia enhancing the resistance to malaria and to episodes in human history when mercenary city defenders offered either net benefits or imposed net costs, depending on the level of threat from invading armies.

  15. Patient satisfaction and treatment outcome of fungus ball rhinosinusitis treated by functional endoscopic sinus surgery.

    Science.gov (United States)

    Lai, Jui-Chung; Lee, Hong-Shen; Chen, Mu-Kuan; Tsai, Yao-Lung

    2011-02-01

    Fungal rhinosinusitis is an important clinical problem with diverse manifestations. Although many literatures had found low recurrence rate after surgical treatment of fungus ball rhinosinusitis, patient satisfaction and treatment outcomes (symptom-free and symptom improvement rate, etc.) for fungus ball sinusitis are not yet well established. The purpose of this study is to estimate the patient satisfaction and treatment outcome in patients with fungus ball rhinosinusitis undergoing functional endoscopic sinus surgery (FESS). Medical records of consecutive patients with diagnosed fungus ball rhinosinusitis treated by FESS between 1995 and 2005 were reviewed retrospectively. The post-operative improvement in individual symptom was assessed by chart review and telephone visiting. Ninety consecutive patients (21 men and 69 women) were eligible for the study. Six patients (7%) presented bilateral fungus ball rhinosinusitis. Multiple paranasal sinus fungus ball involvements were found in 48 patients (53%). Complete resolution of complaints with respect to nasal discharge, postnasal drip, cough with sputum, nasal bleeding, fetid odor of nose, olfactory dysfunction, nasal obstruction, headache, and facial pain or pressure were described in 74 patients (82%). The overall patient satisfaction rate was 96%. The estimated recurrence rate of fungus ball rhinosinusitis treated with FESS was 3%, with a mean follow-up of 81 months. Treatment protocol of fungus ball rhinosinusitis with FESS and without postoperative antifungal drugs is efficient because of very low recurrence rate, high patient satisfaction, and very high symptom-free rate. Furthermore, the obvious difference of symptom-free rate between fungus ball rhinosinusitis and chronic rhinosinusitis highlights the need of further studies to discover the pathophysiology of fungal sinusitis.

  16. Radiologic characteristics of sinonasal fungus ball: an analysis of 119 cases

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Young-Joon; Kim, Kyubo (Dept. of Otorhinolaryngology, Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)); Kim, Jinna (Dept. of Radiology, Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)); Lee, Jeung-Gweon; Kim, Chang-Hoon (Dept. of Otorhinolaryngology, Yonsei Univ. College of Medicine, Seoul (Korea, Republic of); The Airway Mucus Institute, Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)), email: entman@yuhs.ac; Yoon, Joo-Heon (Dept. of Otorhinolaryngology, Yonsei Univ. College of Medicine, Seoul (Korea, Republic of); The Airway Mucus Institute, Yonsei Univ. College of Medicine, Seoul (Korea, Republic of); Research Center for Human Natural Defense System, Yonsei Univ. College of Medicine, Seoul (Korea, Republic of); BK21 Project for Medical Science, Yonsei Univ. College of Medicine, Seoul (Korea, Republic of))

    2011-09-15

    Background. It is important to differentiate sinonasal fungus ball from non-fungal sinusitis and other forms of fungal sinusitis in order to determine the optimal treatment. In particular, a sinonasal fungus ball, a non-invasive fungal sinusitis, can be characterized by radiologic findings before surgery. Purpose. To differentiate a sinonasal fungus ball from other types of sinusitis and determine optimal treatment on the basis of radiologic findings before surgery. Material and Methods. We studied 119 patients with clinically and pathologically proven sinonasal fungus balls. Their condition was evaluated radiologically with contrast-enhanced CT (99 patients), non-contrast CT (18 patients) and/or MRI (17 patients) prior to sinonasal surgery. Results. Calcifications were found in 78 of 116 (67.2%) patients who underwent CT scans for fungus ball. As opposed to non-contrast CT scans, contrast CT scans revealed hyper attenuating fungal ball in 82.8% and enhanced inflamed mucosa in 65.5% of the patients, respectively. On MRI, most sinonasal fungal balls showed iso- or hypointensity on T1-weighted images and marked hypointensity on T2-weighted images. Inflamed mucosal membranes were noted and appeared as hypointense on T1-weighted images (64.7%) and hyperintense on T2-weighted images (88.2%). Conclusion. When there are no calcifications visible on the CT scan, a hyper attenuating fungal ball located in the central area of the sinus with mucosal thickening on enhanced CT scans is an important feature of a non-invasive sinonasal fungus ball. On MRI, a sinonasal fungus ball has typical features of a marked hypointense fungus ball with a hyperintense mucosal membrane in T2-weighted images. A contrast-enhanced CT scan or MRI provides sufficient information for the preoperative differentiation of a sinonasal fungus ball from other forms of sinusitis

  17. Maxillary reconstruction and placement of dental implants after treatment of a maxillary sinus fungus ball.

    Science.gov (United States)

    Colletti, Giacomo; Felisati, Giovanni; Biglioli, Federico; Tintinelli, Roberto; Valassina, Davide

    2010-01-01

    A fungus ball is one of the fungal diseases that can affect the paranasal sinuses. It requires surgical treatment. Because there is only one previously reported case of dental implant placement after treatment of a maxillary sinus fungus ball, the authors here report on a case of a maxillary sinus fungus ball with bone erosion that was treated surgically with a combined endoscopic endonasal and endoral (Caldwell-Luc) approach. One year later, a graft from the ilium was obtained and a sinus elevation was performed to allow the placement of dental implants. Three months later, the dental implants were placed, and they were all osseointegrated at the 9-month follow-up.

  18. Releasing nitrogen from ammoniated lignin by white rot fungus cometabolizes environmental pollutants

    Institute of Scientific and Technical Information of China (English)

    LIN Lu; ZHAO De-qing; ZHOU Xian-tao; QIU Yu-gui; ZHANG Gan

    2003-01-01

    The nitrogen-modified lignocelluloses(NML) produced under oxic ammoniation was metabolized by white rot fungus, NH4+-N was released, NO3--N concentration was decreased and total nitrogen loss was blocked within incubation period. During releasing nitrogen from the metabolism of NML, white rot fungus cometabolized recalcitrant environmental pollutants and showed higher degradation capability. Results indicated that this NML complex colonized by white rot fungus might be effective with economic feasibility when they are applied into the vast field ecosystem, it might stabilize NH4+ nitrogen flux and bioremediate the polluted environmental sites.

  19. The response of the grape berry moth (Lobesia botrana) to a dietary phytopathogenic fungus (Botrytis cinerea): the significance of fungus sterols.

    Science.gov (United States)

    Mondy; Corio-Costet

    2000-12-01

    A Tortricidae (Lobesia botrana) has a mutualistic relationship with the fungus (Botrytis cinerea). In this study, we investigated the growth, survival, fecundity and amount of sterols and steroids in larvae of this vineyard pest reared on artificial diets containing mycelium (3%) or purified sterols (0.01%) of the phytopathogenic fungus. Two principal questions related to the physiological and biochemical basis of this mutualistic relationship were addressed: (1) how the fungus influences growth, survival, fecundity, sterol and steroid contents of the insect and (2) are fungal sterols involved in the biochemical basis of mutualism? The presence of fungus in the diet led to a decrease of total duration of larval development (mean gain 5.1-9.4 days compared to the total duration in control of 42.9 days), an increase in survival (mean gain 50-76.3%) and fecundity (gain of 94-102%). These positive effects of the fungus on the biology and physiology of the insect were directly correlated to the presence of fungal sterols in the diet. Fungal sterols are one of the biochemical basis of the mutualistic relationship between L. botrana and B. cinerea.

  20. Serpula lacrymans, The Dry Rot Fungus and Tolerance Towards Copper-Based Wood Preservatives

    DEFF Research Database (Denmark)

    Hastrup, Anne Christine Steenkjær; Jensen, Bo; Clausen, Carol;

    2005-01-01

    wood preservatives were the most commonly used preservatives for pressure treatment of wood for building constructions. Because of a suspicion about tolerance toward copper components, a soil block test was undertaken to clarify the effect of two copper based preservatives, copper citrate and ACQ......Serpula lacrymans (Wulfen : Fries) Schröter, the dry rot fungus, is considered the most (Wulfen : Fries) Schröterthe dry rot fungus, is considered the most economically important wood decay fungus in temperate regions of the world i.e. northern Europe, Japan and Australia. Previously copper based......-D, on the dry rot fungus, Serpula lacrymans compared to an alternative non-copper containing wood preservative. The extensive use of copper-based wood preservatives has hastened the need for understanding why some fungi are able to attack copper-treated wood. The copper tolerance of S. lacrymans and other brown...

  1. Peniamidienone and penidilamine, plant growth regulators produced by the fungus Penicillium sp. No. 13.

    Science.gov (United States)

    Kimura, Y; Mizuno, T; Kawano, T; Okada, K; Shimada, A

    2000-04-01

    Peniamidienone and penidilamine were isolated from cultures of the fungus Penicillium sp. No. 13 as new plant growth regulators and their structures were established by NMR spectroscopic studies. Peniamidienone showed weak inhibition of lettuce seedling growth.

  2. Exploring the potential for actinobacteria as defensive symbionts in fungus-growing termites

    DEFF Research Database (Denmark)

    Visser, Anna A.; Nobre, Tânia; Currie, Cameron R.

    2012-01-01

    In fungus-growing termites, fungi of the subgenus Pseudoxylaria threaten colony health through substrate competition with the termite fungus (Termitomyces). The potential mechanisms with which termites suppress Pseudoxylaria have remained unknown. Here we explore if Actinobacteria potentially play...... a role as defensive symbionts against Pseudoxylaria in fungus-growing termites. We sampled for Actinobacteria from 30 fungus-growing termite colonies, spanning the three main termite genera and two geographically distant sites. Our isolations yielded 360 Actinobacteria, from which we selected subsets......-growing termites, indicating lack of specificity. Antibiotic-activity screening of 288 isolates against the fungal cultivar and competitor revealed that most of the Actinobacteria-produced molecules with antifungal activity. A more detailed bioassay on 53 isolates, to test the specificity of antibiotics, showed...

  3. Isolation and characterization of antibacterial compound from a mangrove-endophytic fungus, Penicillium chrysogenum MTCC 5108

    Digital Repository Service at National Institute of Oceanography (India)

    PrabhaDevi; Rodrigues, C.; Naik, C.G.; DeSouza, L.

    ). Quimica Nova 28: 991-995 21. Marinho AMR, Rodrigues-Filho E, Moitinho MDLR, Santos LS (2005) Biologically active polyketides produced by Penicillium janthinellum isolated as an endophytic fungus from fruits of Melia azedarach. J Brazilian Chem Soc 16...

  4. Enhanced production of laccase by a marine fungus during treatment of colored effluents and synthetic dyes

    Digital Repository Service at National Institute of Oceanography (India)

    DeSouza-Ticlo, D.; Tiwari, R.; Sah, A.K.; Raghukumar, C.

    -degrading enzymes are reported to be the most efficient in decolorizing such effluents. We report here decolorization of all the three effluents by a marine fungal isolate, NIOCC # 2a cultured from decaying mangrove wood. The fungus also decolorized several...

  5. Reduced biological control and enhanced chemical pest management in the evolution of fungus farming in ants

    DEFF Research Database (Denmark)

    Fernández-Marín, Hermógenes; Zimmerman, Jess K; Nash, David R

    2009-01-01

    To combat disease, most fungus-growing ants (Attini) use antibiotics from mutualistic bacteria (Pseudonocardia) that are cultured on the ants' exoskeletons and chemical cocktails from exocrine glands, especially the metapleural glands (MG). Previous work has hypothesized that (i) Pseudonocardia...

  6. Co-evolution of enzyme function in the attine ant-fungus symbiosis

    DEFF Research Database (Denmark)

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

    Introduction: Fungus-growing ants cultivate specialized fungi in the tribe Leucocoprineae (Lepiotaceae: Basidiomycota) inside their nests. The conspicuous leaf-cutting ants in the genus Atta build huge nests displacing several cubic meters of soil, whereas lower attine genera such as Cyphomyrmex...... have small nests with a fungus garden the size of a table-tennis ball. Only the leaf-cutting ants are specialized on using fresh leaves as substrate for their fungus gardens, whereas the more basal attine genera use substrates such as dry plant material (leaf litter and small twigs) and also insect...... feces and insect carcasses. This diverse array of fungal substrates across the attine lineage implies that the symbiotic fungus needs different enzymes to break down the plant material that the ants provide or different efficiencies of enzyme function. Methods: (1.) We made a literature survey...

  7. Factors affecting fungus-induced larval mortality in Anopheles gambiae and Anopheles stephensi

    NARCIS (Netherlands)

    Bukhari, S.T.; Middelman, A.; Koenraadt, C.J.M.; Takken, W.; Knols, B.G.J.

    2010-01-01

    Background Entomopathogenic fungi have shown great potential for the control of adult malaria vectors. However, their ability to control aquatic stages of anopheline vectors remains largely unexplored. Therefore, how larval characteristics (Anopheles species, age and larval density), fungus (species

  8. The dynamics of plant cell-wall polysaccharide decomposition in leaf-cutting ant fungus gardens

    DEFF Research Database (Denmark)

    Moller, Isabel Eva; de Fine Licht, Henrik Hjarvard; Harholt, Jesper;

    2011-01-01

    The degradation of live plant biomass in fungus gardens of leaf-cutting ants is poorly characterised but fundamental for understanding the mutual advantages and efficiency of this obligate nutritional symbiosis. Controversies about the extent to which the garden-symbiont Leucocoprinus gongylophorus......, to map the occurrence of cell wall polymers in consecutive sections of the fungus garden of the leaf-cutting ant Acromyrmex echinatior. We show that pectin, xyloglucan and some xylan epitopes are degraded, whereas more highly substituted xylan and cellulose epitopes remain as residuals in the waste...... material that the ants remove from their fungus garden. These results demonstrate that biomass entering leaf-cutting ant fungus gardens is only partially utilized and explain why disproportionally large amounts of plant material are needed to sustain colony growth. They also explain why substantial...

  9. Biosorption of copper(II and chromium(VI by modified tea fungus

    Directory of Open Access Journals (Sweden)

    Šćiban Marina B.

    2012-01-01

    Full Text Available The tea fungus was found to have good adsorption capacities for heavy metal ions. In this work it was treated with HCl or NaOH at 20°C or 100°C, with the aim to improve its adsorption ability. The sorption of Cu(II and Cr(VI ions from aqueous solutions by raw and treated tea fungus was investigated in the batch mode. The largest quantity of adsorbed Cu(II, of about 55 mg/g, was achieved by tea fungus modified with NaOH at 100°C. For Cr(VI, the largest quantity of adsorbed anions, of about 58 mg/g, was achieved by the adsorbent modified with NaOH at 20°C. It was shown that acid modification of tea fungus biomass was not effective. [Projekat Ministarstva nauke Republike Srbije, br. III 43005 i br. TR 31002

  10. RESEARCH ARTICLES : Ethanol Production from Various Sugars and Cellulosic Biomass by White Rot Fungus Lenzites betulinus

    National Research Council Canada - National Science Library

    Kyung Hoan Im; ; Trung Kien Nguyen; Jaehyuk Choi; Tae Soo Lee

    2016-01-01

    .... It was found that the mycelia of white rot fungus Lenzites betulinus IUM 5468 produced ethanol from various sugars, including glucose, mannose, galactose, and cellobiose with a yield of 0.38, 0.26, 0.07...

  11. Ethanol Production from Various Sugars and Cellulosic Biomass by White Rot Fungus Lenzites betulinus

    National Research Council Canada - National Science Library

    Im, Kyung Hoan; Nguyen, Trung Kien; Choi, Jaehyuk; Lee, Tae Soo

    2016-01-01

    .... It was found that the mycelia of white rot fungus Lenzites betulinus IUM 5468 produced ethanol from various sugars, including glucose, mannose, galactose, and cellobiose with a yield of 0.38, 0.26, 0.07...

  12. Biodegradation of hazardous waste using white rot fungus: Project planning and concept development document

    Energy Technology Data Exchange (ETDEWEB)

    Luey, J.; Brouns, T.M.; Elliott, M.L.

    1990-11-01

    The white rot fungus Phanerochaete chrysosporium has been shown to effectively degrade pollutants such as trichlorophenol, polychlorinated biphenyls (PCBs), dioxins and other halogenated aromatic compounds. These refractory organic compounds and many others have been identified in the tank waste, groundwater and soil of various US Department of Energy (DOE) sites. The treatment of these refractory organic compounds has been identified as a high priority for DOE's Research, Development, Demonstration, Testing, and Evaluation (RDDT E) waste treatment programs. Unlike many bacteria, the white rot fungus P. chrysosporium is capable of degrading these types of refractory organics and may be valuable for the treatment of wastes containing multiple pollutants. The objectives of this project are to identify DOE waste problems amenable to white rot fungus treatment and to develop and demonstrate white rot fungus treatment process for these hazardous organic compounds. 32 refs., 6 figs., 7 tabs.

  13. Factors affecting fungus-induced larval mortality in Anopheles gambiae and Anopheles stephensi

    NARCIS (Netherlands)

    Bukhari, T.; Middelman, A.; Koenraadt, C.J.M.; Takken, W.; Knols, B.G.J.

    2010-01-01

    Background: Entomopathogenic fungi have shown great potential for the control of adult malaria vectors. However, their ability to control aquatic stages of anopheline vectors remains largely unexplored. Therefore, how larval characteristics (Anopheles species, age and larval density), fungus (specie

  14. Characterization of salt-adapted secreted lignocellulolytic enzymes from the mangrove fungus Pestalotiopsis sp

    OpenAIRE

    Chevret, Didier; Henrissat, Bernard; Berrin, Jean-Guy; Levasseur, Anthony; Record, Eric

    2013-01-01

    Fungi are important for biomass degradation processes in mangrove forests. Given the presence of sea water in these ecosystems, mangrove fungi are adapted to high salinity. Here we isolate Pestalotiopsis sp. NCi6, a halotolerant and lignocellulolytic mangrove fungus of the order Xylariales. We study its lignocellulolytic enzymes and analyse the effects of salinity on its secretomes. De novo transcriptome sequencing and assembly indicate that this fungus possesses of over 400 putative lignocel...

  15. Exploring the potential for actinobacteria as defensive symbionts in fungus-growing termites.

    Science.gov (United States)

    Visser, Anna A; Nobre, Tânia; Currie, Cameron R; Aanen, Duur K; Poulsen, Michael

    2012-05-01

    In fungus-growing termites, fungi of the subgenus Pseudoxylaria threaten colony health through substrate competition with the termite fungus (Termitomyces). The potential mechanisms with which termites suppress Pseudoxylaria have remained unknown. Here we explore if Actinobacteria potentially play a role as defensive symbionts against Pseudoxylaria in fungus-growing termites. We sampled for Actinobacteria from 30 fungus-growing termite colonies, spanning the three main termite genera and two geographically distant sites. Our isolations yielded 360 Actinobacteria, from which we selected subsets for morphological (288 isolates, grouped in 44 morphotypes) and for 16S rRNA (35 isolates, spanning the majority of morphotypes) characterisation. Actinobacteria were found throughout all sampled nests and colony parts and, phylogenetically, they are interspersed with Actinobacteria from origins other than fungus-growing termites, indicating lack of specificity. Antibiotic-activity screening of 288 isolates against the fungal cultivar and competitor revealed that most of the Actinobacteria-produced molecules with antifungal activity. A more detailed bioassay on 53 isolates, to test the specificity of antibiotics, showed that many Actinobacteria inhibit both Pseudoxylaria and Termitomyces, and that the cultivar fungus generally is more susceptible to inhibition than the competitor. This suggests that either defensive symbionts are not present in the system or that they, if present, represent a subset of the community isolated. If so, the antibiotics must be used in a targeted fashion, being applied to specific areas by the termites. We describe the first discovery of an assembly of antibiotic-producing Actinobacteria occurring in fungus-growing termite nests. However, due to the diversity found, and the lack of both phylogenetic and bioactivity specificity, further work is necessary for a better understanding of the putative role of antibiotic-producing bacteria in the fungus

  16. Microalgae harvesting via co-culture with filamentous fungus

    Science.gov (United States)

    Gultom, Sarman Oktovianus

    Microalgae harvesting is a labor- and energy-intensive process. For instance, classical harvesting technologies such as chemical addition and mechanical separation are economically prohibiting for biofuel production. Newer approaches to harvest microalgae have been developed in order to decrease costs. Among these new methods, fungal co-pelletization seems to be a promising technology. By co-culturing filamentous fungi with microalgae, it is possible to form pellets, which can easily be separated. In this study, different parameters for the cultivation of filamentous fungus (Aspergillus niger) and microalgae (Chlorella vulgaris) to efficiently form cell pellets were evaluated under heterotrophic and phototrophic conditions, including organic carbon source (glucose, glycerol and sodium acetate) concentration, pH, initial concentration of fungal spores, initial concentration of microalgal cells, concentration of ionic strength (Calcium and Magnesium) and concentration of salinity (NaCl). In addition, zeta-potential measurements were carried out in order to get a better understanding of the mechanism of attraction. It was found that 2 g/L of glucose, a fungus to microalgae ratio of 1:300, and uncontrolled pH (around 7) are the best culturing conditions for co-pelletization. Under these conditions, it was possible to achieve a high harvesting performance (>90%). In addition, it was observed that most pellets formed in the co-culture were spherical with an average diameter of 3.5 mm and in concentrations of about 5 pellets per mL of culture media. Under phototrophic conditions, co-pelletization required the addition of glucose as organic carbon source to sustain the growth of fungi and to allow the harvesting of microalgae. Zeta-potential measurements indicated that (i) both microalgae and fungi have low zeta-potential values regardless of the pH on the bulk (i.e. <-10 mV) (ii) fungi can have a positive electric charge at low pH (ie. pH=3). These values suggest that it

  17. Alpha-picolinic acid,a fungal toxin and mammal apoptosis-inducing agent,elicits hypersensitive-like response and enhances disease resistance in rice

    Institute of Scientific and Technical Information of China (English)

    Hai Kuo ZHANG; Xin ZHANG; Bi Zeng MAO; Qun LI; Zu Hua HE

    2004-01-01

    Alpha-picolinic acid (PA),a metabolite of tryptophan and an inducer of apoptosis in the animal cell,has been reported to be a toxin produced by some of plant fungal pathogens and used in screening for disease resistant mutants. Here,we report that PA is an efficient apoptosis agent triggering cell death of hypersensitive-like response in planta. Confirmed by Fluorescence Activated Cell Sorter (FACS),rice suspension cells and leaves exhibited programmed cell death induced by PA. The PA-induced cell death was associated with the accumulation of reactive oxygen species that could be blocked by diphenylene iodonium chloride,indicating that the generation of reactive oxygen species was NADPHoxidase dependent. We also demonstrated the induction of rice defense-related genes and subsequent resistant enhancement by PA against the rice blast fungus Magnaporthe grisea. Hence,it was concluded that the PA-stimulated defense response likely involves the onset of the hypersensitive response in rice,which also provides a simple eliciting tool for studying apoptosis in the plant cell.

  18. Enhancing rice resistance to fungal pathogens by transformation with cell wall degrading enzyme genes from Trichoderma atroviride

    Institute of Scientific and Technical Information of China (English)

    LIU Mei (刘梅); SUN Zong-xiu (孙宗修); ZHU Jie (朱洁); XU Tong (徐同); HARMAN Gary E.; LORITO Matteo

    2004-01-01

    Three genes encoding for fungal cell wall degrading enzymes (CWDEs), ech42, nag70 and gluc78 from the biocontrol fungus Trichoderma atroviride were inserted into the binary vector pCAMBIA1305.2 singly and in all possible combinations and transformed to rice plants. More than 1800 independently regenerated plantlets in seven different populations (for each of the three genes and each of the four gene combinations) were obtained. The ech42 gene encoding for an endochitinase increased resistance to sheath blight caused by Rhizoctonia solani, while the exochitinase-encoding gene, nag70, had lesser effect. The expression level of endochitinase but exochitinase was correlated with disease resistance. Nevertheless, exochitinase enhanced the effect of endochitinase on disease resistance when the two genes co-expressed in transgenics. Resistance to Magnaporthe grisea was found in all kinds of regenerated plants including that with single gluc78. A few lines expressing either ech42 or nag70 gene were immune to the disease. Transgenic plants are being tested to further evaluate disease resistance at field level. This is the first report of multiple of expression of genes encoding CWDEs from Trichoderma atroviride that result in resistance to blast and sheath blight in rice.

  19. Characterization and mapping of a novel light-dependent lesion mimic mutant lmm6 in rice (Oryza sativa L.)

    Institute of Scientific and Technical Information of China (English)

    XIAO Gui-qing; ZHANG Hai-wen; LU Xiang-yang; HUANG Rong-feng

    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 lmm6, 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 cel death occurred in lmm6 accompanied with accumulation of reactive oxygen species (ROS). The lower chlorophyl content, soluble protein content and superoxide dismutase (SOD) activity, the higher malondialdehyde (MDA) content were detected in lmm6 than in the wild type (WT). Moreover, the observation by transmission electronic microscope (TEM) demonstrated that some organel es were damaged and the stroma lamel a of chloroplast was irregular and loose in mesophyl cel of lmm6. In addition, lmm6 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 lmm6 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 ifnal y 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 wil be helpful in clarifying the mechanism of cel death and disease resistance in rice.

  20. Deciphering the salinity adaptation mechanism in Penicilliopsis clavariiformis AP, a rare salt tolerant fungus from mangrove.

    Science.gov (United States)

    Kashyap, Prem Lal; Rai, Anuradha; Singh, Ruchi; Chakdar, Hillol; Kumar, Sudheer; Srivastava, Alok Kumar

    2016-07-01

    Penicilliopsis clavariiformis AP, a rare salt tolerant fungus reported for the first time from India was identified through polyphasic taxonomy. Scanning electron microscopy showed that the fungus has unique features such as biverticillate penicilli bearing masses of oval to ellipsoidal conidia. The fungus has been characterized for salt tolerance and to understand the relevance of central carbon metabolism in salt stress adaptation. It showed optimal growth at 24 °C and able to tolerate up to 10% (w/v) NaCl. To understand the mechanism of adaptation to high salinity, activities of the key enzymes regulating glycolysis, pentose phosphate pathway, and tricarboxylic acid cycle were investigated under normal (0% NaCl) and saline stress environment (10% NaCl). The results revealed a re-routing of carbon metabolism away from glycolysis to the pentose phosphate pathway (PPP), served as a cellular stress-resistance mechanism in fungi under saline environment. The detection and significant expression of fungus genes (Hsp98, Hsp60, HTB, and RHO) under saline stress suggest that these halotolerance conferring genes from the fungus could have a role in fungus protection and adaptation under saline environment. Overall, the present findings indicate that the rearrangement of the metabolic fluxes distribution and stress related genes play an important role in cell survival and adaptation under saline environment.

  1. Starch metabolism in Leucoagaricus gongylophorus, the symbiotic fungus of leaf-cutting ants.

    Science.gov (United States)

    Silva, A; Bacci, M; Pagnocca, F C; Bueno, O C; Hebling, M J A

    2006-01-01

    Leucoagaricus gongylophorus, the symbiotic fungus of the leaf-cutting ants, degrades starch, this degradation being supposed to occur in the plant material which leafcutters forage to the nests, generating most of the glucose which the ants utilize for food. In the present investigation, we show that laboratory cultures of L. gongylophorus produce extracellular alpha-amylase and maltase which degrade starch to glucose, reinforcing that the ants can obtain glucose from starch through the symbiotic fungus. Glucose was found to repress alpha-amylase and, more severely, maltase activity, thus repressing starch degradation by L. gongylophorus, so that we hypothesize that: (1) glucose down-regulation of starch degradation also occurs in the Atta sexdens fungus garden; (2) glucose consumption from the fungus garden by A. sexdens stimulates degradation of starch from plant material by L. gongylophorus, which may represent a mechanism by which leafcutters can control enzyme production by the symbiotic fungus. Since glucose is found in the fungus garden inside the nests, down-regulation of starch degradation by glucose is supposed to occur in the nest and play a part in the control of fungal enzyme production by leafcutters.

  2. The dynamics of plant cell-wall polysaccharide decomposition in leaf-cutting ant fungus gardens.

    Directory of Open Access Journals (Sweden)

    Isabel E Moller

    Full Text Available The degradation of live plant biomass in fungus gardens of leaf-cutting ants is poorly characterised but fundamental for understanding the mutual advantages and efficiency of this obligate nutritional symbiosis. Controversies about the extent to which the garden-symbiont Leucocoprinus gongylophorus degrades cellulose have hampered our understanding of the selection forces that induced large scale herbivory and of the ensuing ecological footprint of these ants. Here we use a recently established technique, based on polysaccharide microarrays probed with antibodies and carbohydrate binding modules, to map the occurrence of cell wall polymers in consecutive sections of the fungus garden of the leaf-cutting ant Acromyrmex echinatior. We show that pectin, xyloglucan and some xylan epitopes are degraded, whereas more highly substituted xylan and cellulose epitopes remain as residuals in the waste material that the ants remove from their fungus garden. These results demonstrate that biomass entering leaf-cutting ant fungus gardens is only partially utilized and explain why disproportionally large amounts of plant material are needed to sustain colony growth. They also explain why substantial communities of microbial and invertebrate symbionts have evolved associations with the dump material from leaf-cutting ant nests, to exploit decomposition niches that the ant garden-fungus does not utilize. Our approach thus provides detailed insight into the nutritional benefits and shortcomings associated with fungus-farming in ants.

  3. Fungal garden making inside bamboos by a non-social fungus-growing beetle.

    Science.gov (United States)

    Toki, Wataru; Takahashi, Yukiko; Togashi, Katsumi

    2013-01-01

    In fungus-growing mutualism, it is indispensable for host animals to establish gardens of the symbiotic fungus as rapidly as possible. How to establish fungal gardens has been well-documented in social fungus-farming insects, whereas poorly documented in non-social fungus-farming insects. Here we report that the non-social, fungus-growing lizard beetle Doubledaya bucculenta (Coleoptera: Erotylidae: Languriinae) transmits the symbiotic yeast Wickerhamomyces anomalus from the ovipositor-associated mycangium into bamboo internode cavities and disperses the yeast in the cavities to make gardens. Microbial isolation and cryo-scanning electron microscopy observation revealed that W. anomalus was constantly located on the posterior ends of eggs, where larvae came out, and on the inner openings of oviposition holes. Direct observation of oviposition behavior inside internodes revealed that the distal parts of ovipositors showed a peristaltic movement when they were in contact with the posterior ends of eggs. Rearing experiments showed that W. anomalus was spread much more rapidly and widely on culture media and internodes in the presence of the larvae than in the absence. These results suggest that the ovipositors play a critical role in vertical transmission of W. anomalus and that the larvae contribute actively to the garden establishment, providing a novel case of fungal garden founding in non-social insect-fungus mutualism.

  4. Fungal garden making inside bamboos by a non-social fungus-growing beetle.

    Directory of Open Access Journals (Sweden)

    Wataru Toki

    Full Text Available In fungus-growing mutualism, it is indispensable for host animals to establish gardens of the symbiotic fungus as rapidly as possible. How to establish fungal gardens has been well-documented in social fungus-farming insects, whereas poorly documented in non-social fungus-farming insects. Here we report that the non-social, fungus-growing lizard beetle Doubledaya bucculenta (Coleoptera: Erotylidae: Languriinae transmits the symbiotic yeast Wickerhamomyces anomalus from the ovipositor-associated mycangium into bamboo internode cavities and disperses the yeast in the cavities to make gardens. Microbial isolation and cryo-scanning electron microscopy observation revealed that W. anomalus was constantly located on the posterior ends of eggs, where larvae came out, and on the inner openings of oviposition holes. Direct observation of oviposition behavior inside internodes revealed that the distal parts of ovipositors showed a peristaltic movement when they were in contact with the posterior ends of eggs. Rearing experiments showed that W. anomalus was spread much more rapidly and widely on culture media and internodes in the presence of the larvae than in the absence. These results suggest that the ovipositors play a critical role in vertical transmission of W. anomalus and that the larvae contribute actively to the garden establishment, providing a novel case of fungal garden founding in non-social insect-fungus mutualism.

  5. Specific, non-nutritional association between an ascomycete fungus and Allomerus plant-ants.

    Science.gov (United States)

    Ruiz-González, Mario X; Malé, Pierre-Jean G; Leroy, Céline; Dejean, Alain; Gryta, Hervé; Jargeat, Patricia; Quilichini, Angélique; Orivel, Jérôme

    2011-06-23

    Ant-fungus associations are well known from attine ants, whose nutrition is based on a symbiosis with basidiomycete fungi. Otherwise, only a few non-nutritional ant-fungus associations have been recorded to date. Here we focus on one of these associations involving Allomerus plant-ants that build galleried structures on their myrmecophytic hosts in order to ambush prey. We show that this association is not opportunistic because the ants select from a monophyletic group of closely related fungal haplotypes of an ascomycete species from the order Chaetothyriales that consistently grows on and has been isolated from the galleries. Both the ants' behaviour and an analysis of the genetic population structure of the ants and the fungus argue for host specificity in this interaction. The ants' behaviour reveals a major investment in manipulating, growing and cleaning the fungus. A molecular analysis of the fungus demonstrates the widespread occurrence of one haplotype and many other haplotypes with a lower occurrence, as well as significant variation in the presence of these fungal haplotypes between areas and ant species. Altogether, these results suggest that such an interaction might represent an as-yet undescribed type of specific association between ants and fungus in which the ants cultivate fungal mycelia to strengthen their hunting galleries.

  6. The fungus gardens of leaf-cutter ants undergo a distinct physiological transition during biomass degradation

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Eric L.; Aylward, Frank O.; Kim, Young-Mo; Webb-Robertson, Bobbie-Jo M.; Nicora, Carrie D.; Hu, Zeping; Metz, Thomas O.; Lipton, Mary S.; Smith, Richard D.; Currie, Cameron R.; Burnum-Johnson, Kristin E.

    2014-08-01

    Leaf-cutter ants are dominant herbivores in ecosystems throughout the Neotropics. Rather than directly consuming the fresh foliar biomass they harvest, these ants use it to cultivate specialized fungus gardens. Although recent investigations have shed light on how plant biomass is degraded in fungus gardens, the cycling of nutrients that takes place in these specialized microbial ecosystems is still not well understood. Here, using metametabolomics and metaproteomics techniques, we examine the dynamics of nutrient turnover and biosynthesis in these gardens. Our results reveal that numerous free amino acids and sugars are depleted throughout the process of biomass degradation, indicating that easily accessible nutrients from plant material are readily consumed by microbes in these ecosystems. Accumulation of cellobiose and lignin derivatives near the end of the degradation process is consistent with previous findings of cellulases and laccases produced by Leucoagaricus gongylophorus, the fungus cultivated by leaf-cutter ants. Our results also suggest that ureides may be an important source of nitrogen in fungus gardens, especially during nitrogen-limiting conditions. No free arginine was detected in our metametabolomics experiments despite evidence that the host ants cannot produce this amino acid, suggesting that biosynthesis of this metabolite may be tightly regulated in the fungus garden. These results provide new insights into the dynamics of nutrient cycling that underlie this important ant-fungus symbiosis.

  7. Study of signal transduction factors involved in mycoparasitic response of Trichoderma atroviride

    Institute of Scientific and Technical Information of China (English)

    Lorito M; Zeilinger S; Ambrosino P; Brunner K; Reithner B; Mach R L; Woo S L; Cristilli M; Scala F

    2004-01-01

    @@ Numerous Trichoderma spp. are mycoparasites and commercially applied as biological control agents against a large number of plant pathogenic fungi. The mycoparasitic interaction is host-specific and several research strategies have been applied to identify the main genes and compounds involved in the antagonist-plant-pathogen three-way interaction. During mycoparasitism, signals from the host fungus are recognised by Trichoderma, stimulating antifungal activities that are accompanied by morphological changes and the secretion of hydrolytic enzymes and antibiotics. Interestingly some morphological changes appeared highly conserved in the strategy of pathogenicity within the fungal world, i.e. the formation of appressoria as well as the secretion of hydrolytic enzymes seem to be general mechanisms of attack both for plant pathogens and mycoparasitic antagonists. This knowledge is being used to identify receptors and key components of signalling pathways involved in fungus-fungus interaction. For this purpose we have cloned the first genes (tmk1 , tga1 , tga3) from T. atroviride showing a high similarity to MAP kinase and G protein subunits (see abstract by Zeilinger et al.),which have been found to have an important role in pathogenicity by Magnaporthe grisea. To identify the function and involvement of these factors in mycoparasitism by T. atroviride, tmk1, tga1, tga3disruptant strains were produced. The knock-out mutants were tested by in vivo biocontrol assays for their ability to inhibit soil and foliar plant pathogens such as Rhizoctonia solani, Pythium ultimum and Botrytis cinerea . Disruption of these genes corresponded to a complete loss of biocontrol ability,suggesting a significant role in mycoparasitism. In particular, it has been suggested that tga3 regulates the expression of chitinase-encoding genes, the secretion of the corresponding enzymes and the process of conidiation. Comparative proteome analysis of wild type and disruptants supported this

  8. Biotransformation of indomethacin by the fungus Cunninghamella blakesleeana

    Institute of Scientific and Technical Information of China (English)

    Peng ZHANG; Li-hong LIN; Hai-hua HUANG; Hai-yan XU; Da-fang ZHONG

    2006-01-01

    Aim: To investigate the biotransformation of indomethacin, the first of the newer nonsteroidal anti-inflammatory drugs, by filamentous fungus and to compare the similarities between microbial transformation and mammalian metabolism of indomethacin. Methods: Five strains of Cunninghamella (C elegans AS 3.156, C elegans AS 3.2028, C blakesleeana AS 3.153, C blakesleeana AS 3.910 and C echinulata AS 3.2004) were screened for their ability to catalyze the biotransformation of indomethacin. Indomethacin was partially metabolized by five strains of Cunninghamella, and C blakesleeana AS 3.910 was selected for further investigation. Three metabolites produced by C blakesleeana AS 3.910 were isolated using semi-preparative HPLC, and their structures were identified by a combination analysis of LC/MSn and NMR spectra. These three metabolites were separated and quantitatively assayed by liquid chromatography-ion trap mass spectrometry. Results: After 120 h of incubation with C blakesleeana AS 3.910, approximately 87.4% of indomethacin was metabolized to three metabolites: O-desmethylindomethacin (DMI, M1, 67.2%), Af-deschlorobenzoylindomethacin (DBI, M2,13.3%) and O-desmethyl-AT-deschlorobenzoylindomethacin (DMBI, M3, 6.9%). Three phase I metabolites of indomethacin produced by C blakesleeana AS 3.910 were identical to those obtained in humans. Conclusion: C blakesleeana could be a useful tool for generating the mammalian phase I metabolites of indomethacin.

  9. Pulmonary echinococcal cyst with a filamentous fungus co-infection.

    Science.gov (United States)

    Pandey, P; Dixit, A K; Tanwar, A; Mahajan, N C

    2013-09-01

    Fungal infections are known to colonize the pre-existing lung cavities formed as a result of diseases like tuberculosis, sarcoidosis, bronchiectasis and cavitatary neoplasia, mostly encountered in immunocompromised patients. Pulmonary echinococcal cysts have been reported coexistent with cryptococcosis and other saprophytic mycosis, but the coexistence of aspergillosis and echinococcal cyst is extremely rare and occasionally been reported in English literature. Active invasion and proliferation of the fungi in the laminated ectocyst of the echinococcal cyst is very unusual. We report a case of 60 years old immunocompetent female, presented with cough, chest pain and shortness of breath. The chest X-ray showed a large thick walled cavity in the lower and mid zone of right lung with positive water lily sign. Surgical enucleation of the echinococcal cyst revealed aspergilloma involving the cavity with massive invasion of laminated ectocyst by filamentous fungus, morphologically resembling an Aspergillus species and was further treated with Itraconazole for 3 months. This unique coexistence of active pulmonary echinococcosis and aspergillosis is being reported because of its rarity and clinical importance for its management.

  10. Identification of naphthalene metabolism by white rot fungus Pleurotus eryngii.

    Science.gov (United States)

    Hadibarata, Tony; Teh, Zee Chuang; Rubiyatno; Zubir, Meor Mohd Fikri Ahmad; Khudhair, Ameer Badr; Yusoff, Abdull Rahim Mohd; Salim, Mohd Razman; Hidayat, Topik

    2013-10-01

    The use of biomaterials or microorganisms in PAHs degradation had presented an eye-catching performance. Pleurotus eryngii is a white rot fungus, which is easily isolated from the decayed woods in the tropical rain forest, used to determine the capability to utilize naphthalene, a two-ring polycyclic aromatic hydrocarbon as source of carbon and energy. In the meantime, biotransformation of naphthalene to intermediates and other by-products during degradation was investigated in this study. Pleurotus eryngii had been incubated in liquid medium formulated with naphthalene for 14 days. The presence of metabolites of naphthalene suggests that Pleurotus eryngii begin the ring cleavage by dioxygenation on C1 and C4 position to give 1,4-naphthaquinone. 1,4-Naphthaquinone was further degraded to benzoic acid, where the proposed terepthalic acid is absent in the cultured extract. Further degradation of benzoic acid by Pleurotus eryngii shows the existence of catechol as a result of the combination of decarboxylation and hydroxylation process. Unfortunately, phthalic acid was not detected in this study. Several enzymes, including manganese peroxidase, lignin peroxidase, laccase, 1,2-dioxygenase and 2,3-dioxygenase are enzymes responsible for naphthalene degradation. Reduction of naphthalene and the presence of metabolites in liquid medium showed the ability of Pleurotus eryngii to utilize naphthalene as carbon source instead of a limited glucose amount.

  11. Biotransformation of metoprolol by the fungus Cunninghamella blakes-leeana

    Institute of Scientific and Technical Information of China (English)

    Bin MA; Hai-hua HUANG; Xiao-yan CHEN; Yu-ming SUN; Li-hong LIN; Da-fang ZHONG

    2007-01-01

    Aim: To investigate the biotransformation of metoprolol, a β1-cardioselective adrenoceptor antagonist, by filamentous fungus, and to compare the parallels between microbial transformation and mammalian metabolism. Methods: Five strains of Cunninghamella (C elegans AS 3.156, C elegans AS 3.2028, C echinulata AS 3.2004, C blakesleeana AS 3.153 and AS 3.910) were screened for the ability to transform metoprolol. The metabolites of metoprolol produced by C blakesleeana AS 3.153 were separated and assayed by liquid chromatography-tandem mass spectrometry (LC/MSn). The major metabolites were isolated by semipreparative HPLC and the structures were identified by a combination of LC/MSn and nuclear magnetic resonance analysis. Results: Metoprolol was transformed to 7 metabolites; 2 were identified as new metabolites and 5 were known metabolites in mammals. Conclusion: The microbial transformation of metoprolol was similar to the metabolism in mammals. The fungi belonging to Cunninghamella species could be used as complementary models for predicting in vivo metabolism and producing quantities of metabolite references for drugs like metoprolol.

  12. ENTOMOPATHOGENIC FUNGUS ENTOMOPHAGA MAIMAIGA AND INTEGRATED PEST MANAGEMENT IN SERBIA.

    Science.gov (United States)

    Tabaković-Tosić, Mara

    2015-01-01

    During the latest outbreak of the gypsy moth in Serbia (2009-2014), some areas of Central Serbia were particularly endangered, and one of them was Krusevac region, where the forests give way to orchards in the pattern resembling the tiger's skin. Since the number of the laid egg masses in the autumn 2013 guaranteed the defoliation of both forest tree species and agricultural crops, and the presence of E. maimaigo, in Central Serbia had already been determined, at 30 selected plots the assisted spread of it was performed, through the introduction of the infectious inoculum in the beech and oak forests which border the orchards. Since there was dealt with the living organism--fungus, which is particularly susceptible to the weather conditions (temperature and air humidity, as well as the precipitation), and under the conditions of the global warming and great drought, the special recipe for the preparation of inoculum was made. In the following year the mass epizootic of the gypsy moth caterpillars, of the younger instars (L2 and L3), occurred, which implies that E. maimaiga caused the crash of the outbreak of this most harmful species of the defoliating insects of the forests and orchards.

  13. Five New Cytotoxic Metabolites from the Marine Fungus Neosartorya pseudofischeri

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    Wen-Jian Lan

    2016-01-01

    Full Text Available The marine fungus Neosartorya pseudofischeri was isolated from Acanthaster planci from the South China Sea. In a preliminary bioactivity screening, the crude methanol extract of the fungal mycelia showed significant inhibitory activity against the Sf9 cell line from the fall armyworm Spodoptera frugiperda. Five novel compounds, including 5-olefin phenylpyropene A (1, 13-dehydroxylpyripyropene A (4, deacetylsesquiterpene (7, 5-formyl-6-hydroxy-8-isopropyl-2- naphthoic acid (9 and 6,8-dihydroxy-3-((1E,3E-penta-1,3-dien-1-ylisochroman-1-one (10, together with eleven known compounds, phenylpyropene A (2 and C (3, pyripyropene A (5, 7-deacetylpyripyropene A (6, (1S,2R,4aR,5R,8R,8aR-1,8a-dihydroxy-2-acetoxy-3,8-dimethyl-5- (prop-1-en-2-yl-1,2,4a, 5,6,7,8,8a-octahydronaphthalene (8, isochaetominine C (11, trichodermamide A (12, indolyl-3-acetic acid methyl ester (13, 1-acetyl-β-carboline (14, 1,2,3,4-tetrahydro-6-hydroxyl-2-methyl-l,3,4-trioxopyrazino[l,2-a]-indole (15 and fumiquinazoline F (16, were obtained. The structures of these compounds were determined mainly by MS and NMR data. The absolute configuration of 9 was assigned by the single-crystal X-ray diffraction studies. Compounds 1–11 and 15 showed significant cytotoxicity against the Sf9 cells from S. frugiperda.

  14. Eosinophils in fungus-associated allergic pulmonary disease

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    Sumit eGhosh

    2013-02-01

    Full Text Available Asthma is frequently caused and/or exacerbated by sensitization to fungal allergens, which are ubiquitous in many indoor and outdoor environments. Severe asthma with fungal sensitization is characterized by airway hyperresponsiveness and bronchial constriction in response to an inhaled allergen that is worsened by environmental exposure to airborne fungi and which leads to a disease course that is often very difficult to treat with standard asthma therapies. As a result of complex interactions among inflammatory cells, structural cells, and the intercellular matrix of the allergic lung, patients with sensitization to fungal allergens may experience a greater degree of airway wall remodeling and progressive, accumulated pulmonary dysfunction as part of the disease sequela. From their development in the bone marrow to their recruitment to the lung via chemokine and cytokine networks, eosinophils form an important component of the inflammatory milieu that is associated with this syndrome. Eosinophils are recognized as complex multi-factorial leukocytes with diverse functions in the context of allergic fungal asthma. In this review, we will consider recent advances in our understanding of the molecular mechanisms that are associated with eosinophil development and migration to the allergic lung in response to fungal inhalation, along with the eosinophil’s function in the immune response to and the immunopathology attributed to fungus-associated allergic pulmonary disease.

  15. Characterization of Transposable Elements in the Ectomycorrhizal Fungus Laccaria bicolor

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-01-01

    Background: The publicly available Laccaria bicolor genome sequence has provided a considerable genomic resource allowing systematic identification of transposable elements (TEs) in this symbiotic ectomycorrhizal fungus. Using a TEspecific annotation pipeline we have characterized and analyzed TEs in the L. bicolor S238N-H82 genome. Methodology/Principal Findings: TEs occupy 24% of the 60 Mb L. bicolor genome and represent 25,787 full-length and partial copy elements distributed within 171 families. The most abundant elements were the Copia-like. TEs are not randomly distributed across the genome, but are tightly nested or clustered. The majority of TEs exhibits signs of ancient transposition except some intact copies of terminal inverted repeats (TIRS), long terminal repeats (LTRs) and a large retrotransposon derivative (LARD) element. There were three main periods of TE expansion in L. bicolor: the first from 57 to 10 Mya, the second from 5 to 1 Mya and the most recent from 0.5 Mya ago until now. LTR retrotransposons are closely related to retrotransposons found in another basidiomycete, Coprinopsis cinerea. Conclusions: This analysis 1) represents an initial characterization of TEs in the L. bicolor genome, 2) contributes to improve genome annotation and a greater understanding of the role TEs played in genome organization and evolution and 3) provides a valuable resource for future research on the genome evolution within the Laccaria genus.

  16. Characterization of transposable elements in the ectomycorrhizal fungus Laccaria bicolor.

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    Jessy Labbé

    Full Text Available BACKGROUND: The publicly available Laccaria bicolor genome sequence has provided a considerable genomic resource allowing systematic identification of transposable elements (TEs in this symbiotic ectomycorrhizal fungus. Using a TE-specific annotation pipeline we have characterized and analyzed TEs in the L. bicolor S238N-H82 genome. METHODOLOGY/PRINCIPAL FINDINGS: TEs occupy 24% of the 60 Mb L. bicolor genome and represent 25,787 full-length and partial copy elements distributed within 171 families. The most abundant elements were the Copia-like. TEs are not randomly distributed across the genome, but are tightly nested or clustered. The majority of TEs exhibits signs of ancient transposition except some intact copies of terminal inverted repeats (TIRS, long terminal repeats (LTRs and a large retrotransposon derivative (LARD element. There were three main periods of TE expansion in L. bicolor: the first from 57 to 10 Mya, the second from 5 to 1 Mya and the most recent from 0.5 Mya ago until now. LTR retrotransposons are closely related to retrotransposons found in another basidiomycete, Coprinopsis cinerea. CONCLUSIONS: This analysis 1 represents an initial characterization of TEs in the L. bicolor genome, 2 contributes to improve genome annotation and a greater understanding of the role TEs played in genome organization and evolution and 3 provides a valuable resource for future research on the genome evolution within the Laccaria genus.

  17. Adhesion of the Entomopathogenic Fungus Beauveria (Cordyceps) bassiana to Substrata†

    Science.gov (United States)

    Holder, Diane J.; Keyhani, Nemat O.

    2005-01-01

    The entomopathogenic fungus Beauveria bassiana produces at least three distinct single-cell propagules, aerial conidia, vegetative cells termed blastospores, and submerged conidia, which can be isolated from agar plates, from rich broth liquid cultures, and under nutrient limitation conditions in submerged cultures, respectively. Fluorescently labeled fungal cells were used to quantify the kinetics of adhesion of these cell types to surfaces having various hydrophobic or hydrophilic properties. Aerial conidia adhered poorly to weakly polar surfaces and rapidly to both hydrophobic and hydrophilic surfaces but could be readily washed off the latter surfaces. In contrast, blastospores bound poorly to hydrophobic surfaces, forming small aggregates, bound rapidly to hydrophilic surfaces, and required a longer incubation time to bind to weakly polar surfaces than to hydrophilic surfaces. Submerged conidia displayed the broadest binding specificity, adhering to hydrophobic, weakly polar, and hydrophilic surfaces. The adhesion of the B. bassiana cell types also differed in sensitivity to glycosidase and protease treatments, pH, and addition of various carbohydrate competitors and detergents. The outer cell wall layer of aerial conidia contained sodium dodecyl sulfate-insoluble, trifluoroacetic acid-soluble proteins (presumably hydrophobins) that were not present on either blastospores or submerged conidia. The variations in the cell surface properties leading to the different adhesion qualities of B. bassiana aerial conidia, blastospores, and submerged conidia could lead to rational design decisions for improving the efficacy and possibly the specificity of entomopathogenic fungi for host targets. PMID:16151112

  18. Biosynthesis of vanillin by the fungus Pycnoporus sanguineus MIP 95001

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    Sabrina Moro Villela Pacheco

    2013-09-01

    Full Text Available Vanillin (a substance popularly known as vanilla flavor is one of the most widely used compounds, mainly by food and pharmaceutical industries. This substance can be obtained from the orchid Vanilla planifolia, but this is costly and time consuming. Thus, other methods for obtaining vanillin have been studied. Within this context, the aim of this work was to study the biosynthesis of vanillin by three strains of Pycnoporus sanguineus through the use of vanillic acid as a precursor. The strains were cultured in Petri dishes with a potato dextrose agar medium. Fragments of the media with the fungus were then inoculated in Erlenmeyer flasks with a liquid medium of potato broth and 0.3 g.L-1 of vanillic acid. The flasks remained in a shaker for eight days at 28°C and 120 rpm. Samples were withdrawn once a day (0.8 mL.day-1 for analysis of vanillin, glucose, total phenols, total proteins, and laccase. The results showed that only the MIP 95001 strain promoted the biosynthesis of vanillin. The highest concentration of vanillin was detected on the fourth day of cultivation (8.75 mg.dL-1. The results illustrate the ability to biosynthesize vanillin using Pycnoporus sanguineus (MIP 95001, which suggests a possible route for the biotechnological production of this flavor.

  19. Biodegradation of ciprofloxacin by white rot fungus Pleurotus ostreatus.

    Science.gov (United States)

    Singh, Sushil Kumar; Khajuria, Robinka; Kaur, Loveleen

    2017-05-01

    Unrestricted and reckless use of antibiotics has resulted in their accumulation in environment. This, in turn, has led to the emergence of multiple drug-resistant microbes. The present study focuses on degradation of ciprofloxacin (CIP) by an edible white rot fungus Pleurotus ostreatus. Effect of CIP was determined on radial growth and biomass of P. ostreatus. Titrimetric and spectrophotometric assays were carried out to assess the degrading potential of P. ostreatus towards CIP. It was found that CIP has a stimulatory effect on growth and enzyme activity of P. ostreatus. Maximum enzyme (glucanase, ligninases, laccase) production was observed at the highest concentration of CIP (500 ppm). Antibiotic degradation of about 68.8, 94.25 and 91.34% was estimated after 14 days of incubation at 500 ppm CIP using Titrimetric, Indigo carmine and Methyl orange assay, respectively. Degradation of CIP was further validated by high performance liquid chromatography (HPLC) and microbiological analysis. HPLC analysis revealed 95.07% degradation while microbiological test also exhibited a decreased antimicrobial activity of degraded products against Escherichia coli, Staphylococcus aureus and Streptococcus pyogenes. To the best of our knowledge, this is the first study wherein P. ostreatus was used for the degradation of ciprofloxacin.

  20. Fungus mediated biosynthesis and characterization of zinc oxide nanorods

    Science.gov (United States)

    Venkatesh, K. S.; Palani, N. S.; Krishnamoorthi, S. R.; Thirumal, V.; Ilangovan, R.

    2013-06-01

    Recently nanomaterials have been synthesized through biological approach due to its biocompatibility, inexpensive, eco friendly and it offers easiest experimental protocol and so on. ZnO can be potentially used in various applications. This present study reports the fungus mediated extra-cellular bio synthesis of ZnO nanorods using Fusarium Solani. The dried powder was calcined at 350°C for 1 hour in air. The thermal property of the as synthesized ZnO nanopowder was analyzed through Thermo gravimetric /Differential Thermo gravimetric (TGA / DTG) analysis. The structural and morphological properties of the calcined ZnO nanopowder were studied by XRD and SEM analysis respectively. X ray diffraction result revealed that a peak located at 2θ = 36.2° with (101) plane confirms the presence of Zinc oxide with Hexagonal crystal system. The morphology of the calcined ZnO powder was analyzed by Scanning Electron Microscopy and it clearly indicates the presence of ZnO nanorods. The diameter of the nanorods is in the range of 60 to 95 nm.

  1. Cytotoxic effects of Oosporein isolated from endophytic fungus Cochliobolus kusanoi

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    Rmaesha eA

    2015-09-01

    Full Text Available In the present study, oosporein, a fungal toxic secondary metabolite known to be a toxic agent causing chronic disorders in animals, was isolated from fungus Cochliobolus kusanoi of Nerium oleander L. Toxic effects of oosporein and the possible mechanisms of cytotoxicity as well as the role of oxidative stress in cytotoxicity to MDCK kidney cells and RAW 264.7 splene cells were evaluated in-vitro. Also to know the possible in-vivo toxic effects of oosporein on kidney and spleen, Balb/C mouse were treated with different concentrations of oosporein ranging from 20 uM to 200 µM. After 24 hrs of post exposure histopathological observations were made to know the effects of oosporein on target organs. Oosporein induced elevated levels of ROS generation and high levels of MDA, loss of mitochondrial membrane potential (MMP, induced glutathione hydroxylase production was observed in a dose depended manner. Effects oosporein on chromosomal DNA damage was assessed by Comet assay, and increase in DNA damage were observed in both the studied cell lines by increasing the oosprin concentration. Further, oosporein treatment to studied cell lines indicated significant suppression of oxidative stress related gene (SOD1 and CAT expression, and increased levels of mRNA expression in apoptosis or oxidative stress

  2. Bioactive Chaetoglobosins from the Mangrove Endophytic Fungus Penicillium chrysogenum

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    Song Huang

    2016-09-01

    Full Text Available A novel chaetoglobosin named penochalasin I (1 with a unprecedented six-cyclic 6/5/6/5/6/13 fused ring system, and another new chaetoglobosin named penochalasin J (2, along with chaetoglobosins G, F, C, A, E, armochaetoglobosin I, and cytoglobosin C (3–9 were isolated from the culture of Penicillium chrysogenum V11. Their structures were elucidated by 1D, 2D NMR spectroscopic analysis and high resolution mass spectroscopic data. The absolute configuration of compounds 1 and 2 were determined by comparing the theoretical electronic circular dichroism (ECD calculation with the experimental CD. Compound 1 was the first example, with a six-cyclic fused ring system formed by the connection of C-5 and C-2′ of the chaetoglobosin class. Compounds 5–8 remarkably inhibited the plant pathogenic fungus R. solani (minimum inhibitory concentrations (MICs = 11.79–23.66 μM, and compounds 2, 6, and 7 greatly inhibited C. gloeosporioides (MICs = 23.58–47.35 μM, showing an antifungal activity higher than that of carbendazim. Compound 1 exhibited marked cytotoxicity against MDA-MB-435 and SGC-7901 cells (IC50 < 10 μM, and compounds 6 and 9 showed potent cytotoxicity against SGC-7901 and A549 cells (IC50 < 10 μM.

  3. Bioactive Chaetoglobosins from the Mangrove Endophytic Fungus Penicillium chrysogenum

    Science.gov (United States)

    Huang, Song; Chen, Haiyan; Li, Wensheng; Zhu, Xinwei; Ding, Weijia; Li, Chunyuan

    2016-01-01

    A novel chaetoglobosin named penochalasin I (1) with a unprecedented six-cyclic 6/5/6/5/6/13 fused ring system, and another new chaetoglobosin named penochalasin J (2), along with chaetoglobosins G, F, C, A, E, armochaetoglobosin I, and cytoglobosin C (3–9) were isolated from the culture of Penicillium chrysogenum V11. Their structures were elucidated by 1D, 2D NMR spectroscopic analysis and high resolution mass spectroscopic data. The absolute configuration of compounds 1 and 2 were determined by comparing the theoretical electronic circular dichroism (ECD) calculation with the experimental CD. Compound 1 was the first example, with a six-cyclic fused ring system formed by the connection of C-5 and C-2′ of the chaetoglobosin class. Compounds 5–8 remarkably inhibited the plant pathogenic fungus R. solani (minimum inhibitory concentrations (MICs) = 11.79–23.66 μM), and compounds 2, 6, and 7 greatly inhibited C. gloeosporioides (MICs = 23.58–47.35 μM), showing an antifungal activity higher than that of carbendazim. Compound 1 exhibited marked cytotoxicity against MDA-MB-435 and SGC-7901 cells (IC50 < 10 μM), and compounds 6 and 9 showed potent cytotoxicity against SGC-7901 and A549 cells (IC50 < 10 μM). PMID:27690061

  4. Genes involved in virulence of the entomopathogenic fungus Beauveria bassiana.

    Science.gov (United States)

    Valero-Jiménez, Claudio A; Wiegers, Harm; Zwaan, Bas J; Koenraadt, Constantianus J M; van Kan, Jan A L

    2016-01-01

    Pest insects cause severe damage to global crop production and pose a threat to human health by transmitting diseases. Traditionally, chemical pesticides (insecticides) have been used to control such pests and have proven to be effective only for a limited amount of time because of the rapid spread of genetic insecticide resistance. The basis of this resistance is mostly caused by (co)dominant mutations in single genes, which explains why insecticide use alone is an unsustainable solution. Therefore, robust solutions for insect pest control need to be sought in alternative methods such as biological control agents for which single-gene resistance is less likely to evolve. The entomopathogenic fungus Beauveria bassiana has shown potential as a biological control agent of insects, and insight into the mechanisms of virulence is essential to show the robustness of its use. With the recent availability of the whole genome sequence of B. bassiana, progress in understanding the genetics that constitute virulence toward insects can be made more quickly. In this review we divide the infection process into distinct steps and provide an overview of what is currently known about genes and mechanisms influencing virulence in B. bassiana. We also discuss the need for novel strategies and experimental methods to better understand the infection mechanisms deployed by entomopathogenic fungi. Such knowledge can help improve biocontrol agents, not only by selecting the most virulent genotypes, but also by selecting the genotypes that use combinations of virulence mechanisms for which resistance in the insect host is least likely to develop.

  5. Structural analysis of fungus-derived FAD glucose dehydrogenase.

    Science.gov (United States)

    Yoshida, Hiromi; Sakai, Genki; Mori, Kazushige; Kojima, Katsuhiro; Kamitori, Shigehiro; Sode, Koji

    2015-08-27

    We report the first three-dimensional structure of fungus-derived glucose dehydrogenase using flavin adenine dinucleotide (FAD) as the cofactor. This is currently the most advanced and popular enzyme used in glucose sensor strips manufactured for glycemic control by diabetic patients. We prepared recombinant nonglycosylated FAD-dependent glucose dehydrogenase (FADGDH) derived from Aspergillus flavus (AfGDH) and obtained the X-ray structures of the binary complex of enzyme and reduced FAD at a resolution of 1.78 Å and the ternary complex with reduced FAD and D-glucono-1,5-lactone (LGC) at a resolution of 1.57 Å. The overall structure is similar to that of fungal glucose oxidases (GOxs) reported till date. The ternary complex with reduced FAD and LGC revealed the residues recognizing the substrate. His505 and His548 were subjected for site-directed mutagenesis studies, and these two residues were revealed to form the catalytic pair, as those conserved in GOxs. The absence of residues that recognize the sixth hydroxyl group of the glucose of AfGDH, and the presence of significant cavity around the active site may account for this enzyme activity toward xylose. The structural information will contribute to the further engineering of FADGDH for use in more reliable and economical biosensing technology for diabetes management.

  6. Resolving the polyphyletic nature of Pyricularia (Pyriculariaceae).

    Science.gov (United States)

    Klaubauf, S; Tharreau, D; Fournier, E; Groenewald, J Z; Crous, P W; de Vries, R P; Lebrun, M-H

    2014-09-01

    Species of Pyricularia (magnaporthe-like sexual morphs) are responsible for major diseases on grasses. Pyricularia oryzae (sexual morph Magnaporthe oryzae) is responsible for the major disease of rice called rice blast disease, and foliar diseases of wheat and millet, while Pyricularia grisea (sexual morph Magnaporthe grisea) is responsible for foliar diseases of Digitaria. Magnaporthe salvinii, M. poae and M. rhizophila produce asexual spores that differ from those of Pyricularia sensu stricto that has pyriform, 2-septate conidia produced on conidiophores with sympodial proliferation. Magnaporthe salvinii was recently allocated to Nakataea, while M. poae and M. rhizophila were placed in Magnaporthiopsis. To clarify the taxonomic relationships among species that are magnaporthe- or pyricularia-like in morphology, we analysed phylogenetic relationships among isolates representing a wide range of host plants by using partial DNA sequences of multiple genes such as LSU, ITS, RPB1, actin and calmodulin. Species of Pyricularia s. str. belong to a monophyletic clade that includes all P. oryzae/P. grisea isolates tested, defining the Pyriculariaceae, which is sister to the Ophioceraceae, representing two novel families. These clades are clearly distinct from species belonging to the Gaeumannomyces pro parte/Magnaporthiopsis/Nakataea generic complex that are monophyletic and define the Magnaporthaceae. A few magnaporthe- and pyricularia-like species are unrelated to Magnaporthaceae and Pyriculariaceae. Pyricularia oryzae/P. grisea isolates cluster into two related clades. Host plants such as Eleusine, Oryza, Setaria or Triticum were exclusively infected by isolates from P. oryzae, while some host plant such as Cenchrus, Echinochloa, Lolium, Pennisetum or Zingiber were infected by different Pyricularia species. This demonstrates that host range cannot be used as taxonomic criterion without extensive pathotyping. Our results also show that the typical pyriform, 2

  7. Analysis on blast fungus-responsive characters of a flavonoid phytoalexin sakuranetin; accumulation in infected rice leaves, antifungal activity and detoxification by fungus.

    Science.gov (United States)

    Hasegawa, Morifumi; Mitsuhara, Ichiro; Seo, Shigemi; Okada, Kazunori; Yamane, Hisakazu; Iwai, Takayoshi; Ohashi, Yuko

    2014-08-04

    To understand the role of the rice flavonoid phytoalexin (PA) sakuranetin for blast resistance, the fungus-responsive characteristics were studied. Young rice leaves in a resistant line exhibited hypersensitive reaction (HR) within 3 days post inoculation (dpi) of a spore suspension, and an increase in sakuranetin was detected at 3 dpi, increasing to 4-fold at 4 dpi. In the susceptible line, increased sakuranetin was detected at 4 dpi, but not at 3 dpi, by which a large fungus mass has accumulated without HR. Induced expression of a PA biosynthesis gene OsNOMT for naringenin 7-O-methyltransferase was found before accumulation of sakuranetin in both cultivars. The antifungal activity of sakuranetin was considerably higher than that of the major rice diterpenoid PA momilactone A in vitro and in vivo under similar experimental conditions. The decrease and detoxification of sakuranetin were detected in both solid and liquid mycelium cultures, and they took place slower than those of momilactone A. Estimated local concentration of sakuranetin at HR lesions was thought to be effective for fungus restriction, while that at enlarged lesions in susceptible rice was insufficient. These results indicate possible involvement of sakuranetin in blast resistance and its specific relation to blast fungus.

  8. Factors affecting fungus-induced larval mortality in Anopheles gambiae and Anopheles stephensi

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    Takken Willem

    2010-01-01

    Full Text Available Abstract Background Entomopathogenic fungi have shown great potential for the control of adult malaria vectors. However, their ability to control aquatic stages of anopheline vectors remains largely unexplored. Therefore, how larval characteristics (Anopheles species, age and larval density, fungus (species and concentration and environmental effects (exposure duration and food availability influence larval mortality caused by fungus, was studied. Methods Laboratory bioassays were performed on the larval stages of Anopheles gambiae and Anopheles stephensi with spores of two fungus species, Metarhizium anisopliae and Beauveria bassiana. For various larval and fungal characteristics and environmental effects the time to death was determined and survival curves established. These curves were compared by Kaplan Meier and Cox regression analyses. Results Beauveria bassiana and Metarhizium anisopliae caused high mortality of An. gambiae and An. stephensi larvae. However, Beauveria bassiana was less effective (Hazard ratio (HR Metarhizium anisopliae. Anopheles stephensi and An. gambiae were equally susceptible to each fungus. Older larvae were less likely to die than young larvae (HR Conclusions This study shows that both fungus species have potential to kill mosquitoes in the larval stage, and that mortality rate depends on fungus species itself, larval stage targeted, larval density and amount of nutrients available to the larvae. Increasing the concentration of fungal spores or reducing the exposure time to spores did not show a proportional increase and decrease in mortality rate, respectively, because the spores clumped together. As a result spores did not provide uniform coverage over space and time. It is, therefore, necessary to develop a formulation that allows the spores to spread over the water surface. Apart from formulation appropriate delivery methods are also necessary to avoid exposing non-target organisms to fungus.

  9. Slope aspect influences arbuscular mycorrhizal fungus communities in arid ecosystems of the Daqingshan Mountains, Inner Mongolia, North China.

    Science.gov (United States)

    Liu, Min; Zheng, Rong; Bai, Shulan; Bai, Yv E; Wang, Jugang

    2017-04-01

    Arbuscular mycorrhizal (AM) symbiosis plays an important role in ecosystem functioning, particularly in fragile environments. Little is known, however, about how AM fungus community composition responds to slope aspect. Our objective was to compare the AM fungus communities between sunny and shady slopes and to detect factors that influenced the distributions of AM fungi in arid ecosystems of the Daqingshan Mountains, Inner Mongolia, North China. AM fungus communities were evaluated based on small subunit ribosomal RNA genes (SSUs) using Illumina MiSeq sequencing. AM fungus community composition differed significantly between slope aspects, and sunny slopes had significantly higher AM fungus diversity and richness as well as spore density, total root colonization, arbuscule abundance, vesicle abundance, and hyphal colonization than shady slopes. Structural equation modeling (SEM) illustrated that the effects of slope aspect on AM fungus richness likely were mediated by available phosphorus, soil organic carbon, plant cover, and plant diversity. Available phosphorus was the principal factor that influenced AM fungus species richness, and soil organic carbon was the principal factor influencing spore density and total root colonization, suggesting that these factors especially might be responsible for differences between the AM fungus communities of different slope aspects. These findings elucidate the influence of slope aspect on AM fungus communities and may inform use of AM fungi in protection and restoration of vegetation with different slope aspects in arid ecosystems.

  10. Pseudomonas fluorescens WCS374r-induced systemic resistance in rice against Magnaporthe oryzae is based on pseudobactin-mediated priming for a salicylic acid-repressible multifaceted defense response.

    Science.gov (United States)

    De Vleesschauwer, David; Djavaheri, Mohammad; Bakker, Peter A H M; Höfte, Monica

    2008-12-01

    Selected strains of nonpathogenic rhizobacteria can reduce disease in foliar tissues through the induction of a defense state known as induced systemic resistance (ISR). Compared with the large body of information on ISR in dicotyledonous plants, little is known about the mechanisms underlying rhizobacteria-induced resistance in cereal crops. Here, we demonstrate the ability of Pseudomonas fluorescens WCS374r to trigger ISR in rice (Oryza sativa) against the leaf blast pathogen Magnaporthe oryzae. Using salicylic acid (SA)-nonaccumulating NahG rice, an ethylene-insensitive OsEIN2 antisense line, and the jasmonate-deficient mutant hebiba, we show that this WCS374r-induced resistance is regulated by an SA-independent but jasmonic acid/ethylene-modulated signal transduction pathway. Bacterial mutant analysis uncovered a pseudobactin-type siderophore as the crucial determinant responsible for ISR elicitation. Root application of WCS374r-derived pseudobactin (Psb374) primed naive leaves for accelerated expression of a pronounced multifaceted defense response, consisting of rapid recruitment of phenolic compounds at sites of pathogen entry, concerted expression of a diverse set of structural defenses, and a timely hyperinduction of hydrogen peroxide formation putatively driving cell wall fortification. Exogenous SA application alleviated this Psb374-modulated defense priming, while Psb374 pretreatment antagonized infection-induced transcription of SA-responsive PR genes, suggesting that the Psb374- and SA-modulated signaling pathways are mutually antagonistic. Interestingly, in sharp contrast to WCS374r-mediated ISR, chemical induction of blast resistance by the SA analog benzothiadiazole was independent of jasmonic acid/ethylene signaling and involved the potentiation of SA-responsive gene expression. Together, these results offer novel insights into the signaling circuitry governing induced resistance against M. oryzae and suggest that rice is endowed with multiple

  11. Genomic insight into pathogenicity of dematiaceous fungus Corynespora cassiicola

    Science.gov (United States)

    Looi, Hong Keat; Toh, Yue Fen; Yew, Su Mei; Na, Shiang Ling; Tan, Yung-Chie; Chong, Pei-Sin; Khoo, Jia-Shiun; Yee, Wai-Yan; Ng, Kee Peng

    2017-01-01

    Corynespora cassiicola is a common plant pathogen that causes leaf spot disease in a broad range of crop, and it heavily affect rubber trees in Malaysia (Hsueh, 2011; Nghia et al., 2008). The isolation of UM 591 from a patient’s contact lens indicates the pathogenic potential of this dematiaceous fungus in human. However, the underlying factors that contribute to the opportunistic cross-infection have not been fully studied. We employed genome sequencing and gene homology annotations in attempt to identify these factors in UM 591 using data obtained from publicly available bioinformatics databases. The assembly size of UM 591 genome is 41.8 Mbp, and a total of 13,531 (≥99 bp) genes have been predicted. UM 591 is enriched with genes that encode for glycoside hydrolases, carbohydrate esterases, auxiliary activity enzymes and cell wall degrading enzymes. Virulent genes comprising of CAZymes, peptidases, and hypervirulence-associated cutinases were found to be present in the fungal genome. Comparative analysis result shows that UM 591 possesses higher number of carbohydrate esterases family 10 (CE10) CAZymes compared to other species of fungi in this study, and these enzymes hydrolyses wide range of carbohydrate and non-carbohydrate substrates. Putative melanin, siderophore, ent-kaurene, and lycopene biosynthesis gene clusters are predicted, and these gene clusters denote that UM 591 are capable of protecting itself from the UV and chemical stresses, allowing it to adapt to different environment. Putative sterigmatocystin, HC-toxin, cercosporin, and gliotoxin biosynthesis gene cluster are predicted. This finding have highlighted the necrotrophic and invasive nature of UM 591. PMID:28149676

  12. Host Specialization in the Charcoal Rot Fungus, Macrophomina phaseolina.

    Science.gov (United States)

    Su, G; Suh, S O; Schneider, R W; Russin, J S

    2001-02-01

    ABSTRACT To investigate host specialization in Macrophomina phaseolina, the fungus was isolated from soybean, corn, sorghum, and cotton root tissue and soil from fields cropped continuously to these species for 15 years in St. Joseph, LA. Chlorate phenotype of each isolate was determined after growing on a minimal medium containing 120 mM potassium chlorate. Consistent differences in chlorate sensitivity were detected among isolates from different hosts and from soil versus root. To further explore genetic differentiation among fungal isolates from each host, these isolates were examined by restriction fragment length polymorphism and random amplified polymorphic DNA (RAPD) analysis. No variations were observed among isolates in restriction patterns of DNA fragments amplified by polymerase chain reaction covering the internal transcribed spacer region, 5.8S rRNA and part of 25S rRNA, suggesting that M. phaseolina constitutes a single species. Ten random primers were used to amplify the total DNA of 45 isolates, and banding patterns resulting from RAPD analysis were compared with the neighbor-joining method. Isolates from a given host were genetically similar to each other but distinctly different from those from other hosts. Chlorate-sensitive isolates were distinct from chlorate-resistant isolates within a given host. In greenhouse tests, soybean, sorghum, corn, and cotton were grown separately in soil infested with individual isolates of M. phaseolina that were chosen based on their host of origin and chlorate phenotype. Root colonization and plant weight were measured after harvesting. More colonization of corn roots occurred when corn was grown in soil containing corn isolates compared with isolates from other hosts. However, there was no host specialization in isolates from soybean, sorghum, or cotton. More root colonization in soybean occurred with chlorate-sensitive than with chlorate-resistant isolates.

  13. Infection of Psoroptes mites with the fungus Metarhizium anisopliae.

    Science.gov (United States)

    Brooks, A J; Wall, R

    2001-01-01

    The astigmatid mite, Psoroptes ovis (Hering) (Acari: Psoroptidae), is an obligatory ectoparasite that causes psoroptic mange in a range of domesticated animals, particularly sheep, where the clinical disease is known as sheep scab. A series of laboratory assays were used to assess the use of the fungus, Metarhizium anisopliae (Metchnikoff) (Deuteromycotina: Hyphomycetes) as a biocontrol agent for P. ovis derived from rabbits (syn. P. cuniculi). The immersion of mites in a suspension of conidia of M. anisopliae resulted in the acquisition of fatal infections. The number of mites which developed infections increased significantly with the increasing concentration of the conidial suspension to which they were exposed; 77% of mites developed infections when exposed to the highest concentration used (1 x 10(8) conidia ml(-1)). Controls developed no fungal infections. Mites allowed simply to walk across a surface which had been treated with a suspension of conidia also acquired fungal infections; the number infected was again related to the concentration of conidia present. After contact for 24 h with a surface treated with 1 x 10(8) conidia ml(-1), 73% of the mites became infected. To determine whether dead infected mites could act as sources of infection, infected cadavers were placed in chambers with live uninfected mites. The uninfected mites acquired fatal infections from the cadavers; a higher ratio of infected cadavers to uninfected mites resulted in greater transmission of infection. The time after death of the infected cadaver was also an important factor influencing the number infected, 5-day-old cadavers were the most infective and 18-day-old cadavers the least infective. The results indicate that M. anisopliae is a good candidate control agent for Psoroptes mites.

  14. Trade-offs in an ant-plant-fungus mutualism.

    Science.gov (United States)

    Orivel, Jérôme; Malé, Pierre-Jean; Lauth, Jérémie; Roux, Olivier; Petitclerc, Frédéric; Dejean, Alain; Leroy, Céline

    2017-03-15

    Species engaged in multiple, simultaneous mutualisms are subject to trade-offs in their mutualistic investment if the traits involved in each interaction are overlapping, which can lead to conflicts and affect the longevity of these associations. We investigate this issue via a tripartite mutualism involving an ant plant, two competing ant species and a fungus the ants cultivate to build galleries under the stems of their host plant to capture insect prey. The use of the galleries represents an innovative prey capture strategy compared with the more typical strategy of foraging on leaves. However, because of a limited worker force in their colonies, the prey capture behaviour of the ants results in a trade-off between plant protection (i.e. the ants patrol the foliage and attack intruders including herbivores) and ambushing prey in the galleries, which has a cascading effect on the fitness of all of the partners. The quantification of partners' traits and effects showed that the two ant species differed in their mutualistic investment. Less investment in the galleries (i.e. in fungal cultivation) translated into more benefits for the plant in terms of less herbivory and higher growth rates and vice versa. However, the greater vegetative growth of the plants did not produce a positive fitness effect for the better mutualistic ant species in terms of colony size and production of sexuals nor was the mutualist compensated by the wider dispersal of its queens. As a consequence, although the better ant mutualist is the one that provides more benefits to its host plant, its lower host-plant exploitation does not give this ant species a competitive advantage. The local coexistence of the ant species is thus fleeting and should eventually lead to the exclusion of the less competitive species. © 2017 The Author(s).

  15. Genomic insight into pathogenicity of dematiaceous fungus Corynespora cassiicola

    Directory of Open Access Journals (Sweden)

    Hong Keat Looi

    2017-01-01

    Full Text Available Corynespora cassiicola is a common plant pathogen that causes leaf spot disease in a broad range of crop, and it heavily affect rubber trees in Malaysia (Hsueh, 2011; Nghia et al., 2008. The isolation of UM 591 from a patient’s contact lens indicates the pathogenic potential of this dematiaceous fungus in human. However, the underlying factors that contribute to the opportunistic cross-infection have not been fully studied. We employed genome sequencing and gene homology annotations in attempt to identify these factors in UM 591 using data obtained from publicly available bioinformatics databases. The assembly size of UM 591 genome is 41.8 Mbp, and a total of 13,531 (≥99 bp genes have been predicted. UM 591 is enriched with genes that encode for glycoside hydrolases, carbohydrate esterases, auxiliary activity enzymes and cell wall degrading enzymes. Virulent genes comprising of CAZymes, peptidases, and hypervirulence-associated cutinases were found to be present in the fungal genome. Comparative analysis result shows that UM 591 possesses higher number of carbohydrate esterases family 10 (CE10 CAZymes compared to other species of fungi in this study, and these enzymes hydrolyses wide range of carbohydrate and non-carbohydrate substrates. Putative melanin, siderophore, ent-kaurene, and lycopene biosynthesis gene clusters are predicted, and these gene clusters denote that UM 591 are capable of protecting itself from the UV and chemical stresses, allowing it to adapt to different environment. Putative sterigmatocystin, HC-toxin, cercosporin, and gliotoxin biosynthesis gene cluster are predicted. This finding have highlighted the necrotrophic and invasive nature of UM 591.

  16. Genome characterization of the oleaginous fungus Mortierella alpina.

    Directory of Open Access Journals (Sweden)

    Lei Wang

    Full Text Available Mortierella alpina is an oleaginous fungus which can produce lipids accounting for up to 50% of its dry weight in the form of triacylglycerols. It is used commercially for the production of arachidonic acid. Using a combination of high throughput sequencing and lipid profiling, we have assembled the M. alpina genome, mapped its lipogenesis pathway and determined its major lipid species. The 38.38 Mb M. alpina genome shows a high degree of gene duplications. Approximately 50% of its 12,796 gene models, and 60% of genes in the predicted lipogenesis pathway, belong to multigene families. Notably, M. alpina has 18 lipase genes, of which 11 contain the class 2 lipase domain and may share a similar function. M. alpina's fatty acid synthase is a single polypeptide containing all of the catalytic domains required for fatty acid synthesis from acetyl-CoA and malonyl-CoA, whereas in many fungi this enzyme is comprised of two polypeptides. Major lipids were profiled to confirm the products predicted in the lipogenesis pathway. M. alpina produces a complex mixture of glycerolipids, glycerophospholipids and sphingolipids. In contrast, only two major sterol lipids, desmosterol and 24(28-methylene-cholesterol, were detected. Phylogenetic analysis based on genes involved in lipid metabolism suggests that oleaginous fungi may have acquired their lipogenic capacity during evolution after the divergence of Ascomycota, Basidiomycota, Chytridiomycota and Mucoromycota. Our study provides the first draft genome and comprehensive lipid profile for M. alpina, and lays the foundation for possible genetic engineering of M. alpina to produce higher levels and diverse contents of dietary lipids.

  17. Metagenomic and metaproteomic insights into bacterial communities in leaf-cutter ant fungus gardens.

    Science.gov (United States)

    Aylward, Frank O; Burnum, Kristin E; Scott, Jarrod J; Suen, Garret; Tringe, Susannah G; Adams, Sandra M; Barry, Kerrie W; Nicora, Carrie D; Piehowski, Paul D; Purvine, Samuel O; Starrett, Gabriel J; Goodwin, Lynne A; Smith, Richard D; Lipton, Mary S; Currie, Cameron R

    2012-09-01

    Herbivores gain access to nutrients stored in plant biomass largely by harnessing the metabolic activities of microbes. Leaf-cutter ants of the genus Atta are a hallmark example; these dominant neotropical herbivores cultivate symbiotic fungus gardens on large quantities of fresh plant forage. As the external digestive system of the ants, fungus gardens facilitate the production and sustenance of millions of workers. Using metagenomic and metaproteomic techniques, we characterize the bacterial diversity and physiological potential of fungus gardens from two species of Atta. Our analysis of over 1.2 Gbp of community metagenomic sequence and three 16S pyrotag libraries reveals that in addition to harboring the dominant fungal crop, these ecosystems contain abundant populations of Enterobacteriaceae, including the genera Enterobacter, Pantoea, Klebsiella, Citrobacter and Escherichia. We show that these bacterial communities possess genes associated with lignocellulose degradation and diverse biosynthetic pathways, suggesting that they play a role in nutrient cycling by converting the nitrogen-poor forage of the ants into B-vitamins, amino acids and other cellular components. Our metaproteomic analysis confirms that bacterial glycosyl hydrolases and proteins with putative biosynthetic functions are produced in both field-collected and laboratory-reared colonies. These results are consistent with the hypothesis that fungus gardens are specialized fungus-bacteria communities that convert plant material into energy for their ant hosts. Together with recent investigations into the microbial symbionts of vertebrates, our work underscores the importance of microbial communities in the ecology and evolution of herbivorous metazoans.

  18. Combining microtomy and confocal laser scanning microscopy for structural analyses of plant-fungus associations.

    Science.gov (United States)

    Rath, Magnus; Grolig, Franz; Haueisen, Janine; Imhof, Stephan

    2014-05-01

    The serious problem of extended tissue thickness in the analysis of plant-fungus associations was overcome using a new method that combines physical and optical sectioning of the resin-embedded sample by microtomy and confocal microscopy. Improved tissue infiltration of the fungal-specific, high molecular weight fluorescent probe wheat germ agglutinin conjugated to Alexa Fluor® 633 resulted in high fungus-specific fluorescence even in deeper tissue sections. If autofluorescence was insufficient, additional counterstaining with Calcofluor White M2R or propidium iodide was applied in order to visualise the host plant tissues. Alternatively, the non-specific fluorochrome acid fuchsine was used for rapid staining of both, the plant and the fungal cells. The intricate spatial arrangements of the plant and fungal cells were preserved by immobilization in the hydrophilic resin Unicryl™. Microtomy was used to section the resin-embedded roots or leaves until the desired plane was reached. The data sets generated by confocal laser scanning microscopy of the remaining resin stubs allowed the precise spatial reconstruction of complex structures in the plant-fungus associations of interest. This approach was successfully tested on tissues from ectomycorrhiza (Betula pendula), arbuscular mycorrhiza (Galium aparine; Polygala paniculata, Polygala rupestris), ericoid mycorrhiza (Calluna vulgaris), orchid mycorrhiza (Limodorum abortivum, Serapias parviflora) and on one leaf-fungus association (Zymoseptoria tritici on Triticum aestivum). The method provides an efficient visualisation protocol applicable with a wide range of plant-fungus symbioses.

  19. Metagenomic and metaproteomic insights into bacterial communities in leaf-cutter ant fungus gardens

    Energy Technology Data Exchange (ETDEWEB)

    Aylward, Frank O.; Burnum, Kristin E.; Scott, Jarrod J.; Suen, Garret; Tringe, Susannah G.; Adams, Sandra M.; Barry, Kerrie W.; Nicora, Carrie D.; Piehowski, Paul D.; Purvine, Samuel O.; Starrett, Gabriel J.; Goodwin, Lynne A.; Smith, Richard D.; Lipton, Mary S.; Currie, Cameron R.

    2012-09-01

    Herbivores gain access to nutrients stored in plant biomass largely by harnessing the metabolic activities of microbes. Leaf-cutter ants of the genus Atta are a hallmark example; these dominant Neotropical herbivores cultivate symbiotic fungus gardens on massive quantities of fresh plant forage. As the external digestive system of the ants, fungus gardens facilitate the production and sustenance of millions of workers in mature Atta colonies. Here we use metagenomic, and metaproteomic techniques to characterize the bacterial diversity and overall physiological potential of fungus gardens from two species of Atta. Our analysis of over 1.2 Gbp of community metagenomic sequence and three 16S pyrotag libraries reveals that, in addition to harboring the dominant fungal crop, these ecosystems contain abundant populations of Enterobacteriaceae, including the genera Enterobacter, Pantoea, Klebsiella, Citrobacter, and Escherichia. We show that these bacterial communities possess genes commonly associated with lignocellulose degradation, and likely participate in the processing of plant biomass. Additionally, we demonstrate that bacteria in these environments encode a diverse suite of biosynthetic pathways, and that they may enrich the nitrogen-poor forage of the ants with B-vitamins, amino acids, and proteins. These results are consistent with the hypothesis that fungus gardens are highly-specialized fungus-bacteria communities that efficiently convert plant material into usable energy for their ant hosts. Together with recent investigations into the microbial symbionts of vertebrates, our work underscores the importance of microbial communities to the ecology and evolution of herbivorous metazoans.

  20. Appressorium formation in the corn smut fungus Ustilago maydis requires a G2 cell cycle arrest.

    Science.gov (United States)

    Castanheira, Sónia; Pérez-Martín, José

    2015-01-01

    Many of the most important plant diseases are caused by fungal pathogens that form specialized cell structures to breach the leaf surface as well as to proliferate inside the plant. To initiate pathogenic development, the fungus responds to a set of inductive cues. Some of them are of extracellular nature (environmental signals) while others respond to intracellular conditions (developmental signals). These signals have to be integrated into a single response that has as a major outcome changes in the morphogenesis of the fungus. The cell cycle regulation is pivotal during these cellular differentiations, and we hypothesized that cell cycle regulation would be likely to provide control points for infection development by fungal pathogens. Although efforts have been done in various fungal systems, there is still limited information available regarding the relationship of these processes with the induction of the virulence programs. Hence, the role of fungal cell cycle regulators -which are wide conserved elements- as true virulence factors, has yet to be defined. Here we discuss the recent finding that the formation of the appressorium, a structure required for plant penetration, in the corn smut fungus Ustilago maydis seems to be incompatible with an active cell cycle and, therefore genetic circuits evolved in this fungus to arrest the cell cycle during the growth of this fungus on plant surface, before the appressorium-mediated penetration into the plant tissue.