The Experts below are selected from a list of 4809 Experts worldwide ranked by ideXlab platform
Paola Bonfante - One of the best experts on this subject based on the ideXlab platform.
-
gbrowse installation and customization to display the Gigaspora margarita beg34 mitochondrial genome data
2015Co-Authors: Stefano Ghignone, Francesco Venice, Giancarlo Birello, Paola BonfanteAbstract:Summary The Generic Genome Browser (GBrowse) is a simple but highly congurable web-based genome browser. GBrowse consists in a combination of database, interactive web pages and a rich set of utilities for manipulating and displaying annotations on genomes. The Gbrowse platform has been largely used as visualization tool for most of the model organisms. This tutorial shows how to congure a GBrowse genome browser installation to display the mitochondrial genome annotation of the Arbuscular Mycorrhizal Fungus Gigaspora margarita BEG34.
-
candidatus glomeribacter Gigasporarum gen nov sp nov an endosymbiont of arbuscular mycorrhizal fungi
International Journal of Systematic and Evolutionary Microbiology, 2003Co-Authors: Valeria Bianciotto, Erica Lumini, Paola Bonfante, Peter VandammeAbstract:Arbuscular mycorrhizal fungi are obligate endosymbionts that colonize the roots of almost 80 % of land plants. The present paper describes morphological and molecular data on a bacterial endosymbiont living in the cytoplasm of dormant or germinating spores and symbiotic mycelia of the fungal species Gigaspora margarita, Scutellospora persica and Scutellospora castanea. PCR amplification of almost the entire 16S rRNA gene of the Gigaspora margarita BEG 34 endosymbiont, using universal bacterial primers, and subsequent sequence analysis demonstrated that this organism occupies a very distinct phylogenetic position within the beta-Proteobacteria, with the genera Burkholderia, Pandoraea and Ralstonia as its closest neighbours. Primers specific to the 16S rDNA of the endosymbiotic bacteria of BEG 34 allowed amplification of spore DNA from endosymbionts of Gigaspora margarita, Gigaspora decipiens, S. persica and S. castanea, but not from the Gigaspora gigantea endosymbiont (which was morphologically different) or from the cytoplasm of Gigaspora rosea (which did not contain endosymbiotic bacteria). These specific primers were successfully used as a probe for the in-situ hybridization of endobacteria in Gigaspora margarita spores. The overall rod-shaped morphology of the Gigaspora margarita, Gigaspora decipiens, S. persica and S. castanea endosymbionts was similar, and amplification and sequence analysis of the almost-complete 16S rRNA genes of several Gigaspora margarita, S. persica and S. castanea endosymbionts revealed over 98% sequence similarity. These morphological and genomic characteristics were used to assign the endosymbionts of these three species (five isolates) of arbuscular mycorrhizal fungi as 'Candidatus Glomeribacter Gigasporarum' gen. nov., sp. nov.
-
detection and identification of bacterial endosymbionts in arbuscular mycorrhizal fungi belonging to the family Gigasporaceae
Applied and Environmental Microbiology, 2000Co-Authors: Valeria Bianciotto, Erica Lumini, Paola Bonfante, Luisa Lanfranco, Daniela Minerdi, Silvia PerottoAbstract:Intracellular bacteria have been found previously in one isolate of the arbuscular mycorrhizal (AM) fungus Gigaspora margarita BEG 34. In this study, we extended our investigation to 11 fungal isolates obtained from different geographic areas and belonging to six different species of the family Gigasporaceae. With the exception of Gigaspora rosea, isolates of all of the AM species harbored bacteria, and their DNA could be PCR amplified with universal bacterial primers. Primers specific for the endosymbiotic bacteria of BEG 34 could also amplify spore DNA from four species. These specific primers were successfully used as probes for in situ hybridization of endobacteria in G. margarita spores. Neighbor-joining analysis of the 16S ribosomal DNA sequences obtained from isolates of Scutellospora persica, Scutellospora castanea, and G. margarita revealed a single, strongly supported branch nested in the genus Burkholderia.
-
identification of a putative p transporter operon in the genome of a burkholderia strain living inside the arbuscular mycorrhizal fungus Gigaspora margarita
Journal of Bacteriology, 1999Co-Authors: Juan Manuel Ruizlozano, Paola BonfanteAbstract:This article reports the identification of a putative P-transporter operon in the genome of a Burkholderia sp. living in the cytoplasm of the arbuscular mycorrhizal fungus Gigaspora margarita. Its presence suggests that Burkholderia sp. has the potential for P uptake from this environment. This finding raises new questions concerning the importance of intracellular bacteria for mycorrhizal symbiosis.
-
expression of chitin synthase genes in the arbuscular mycorrhizal fungus Gigaspora margarita
New Phytologist, 1999Co-Authors: Luisa Lanfranco, Marta Vallino, Paola BonfanteAbstract:Genomic DNA from spores of the endomycorrhizal fungus Gigaspora margarita was amplified with two sets of degenerate primers designed on conserved regions of chitin synthase polypeptides. Three chitin synthase (chs) gene portions were identified: Gimchs1, Gimchs2 and Gimchs3, encoding one class II and two class IV chitin synthases, respectively. Gimchs1 and Gimchs3 transcripts were detected by reverse transcription polymerase chain reaction (RT-PCR) during root colonization, whereas none of three mRNAs was revealed during spore germination. The potential role of the genes expressed is discussed in the light of morphogenetic and signalling events.
Masanori Saito - One of the best experts on this subject based on the ideXlab platform.
-
application of a molecular method for the identification of a Gigaspora margarita isolate released in a field
Soil Science and Plant Nutrition, 2005Co-Authors: Kazuhira Yokoyama, Masanori Saito, Takahiro Tateishi, Takuya MarumotoAbstract:A molecular technique for the identification of the Gigaspora margarita isolate CK based on the detection of a DNA sequence of 235 bp as its diagnostic marker was evaluated to investigate the survival and establishment of introduced arbuscular mycorrizal fungi (AMF) in a field ecosystem. In March 2001, roots and rhizosphere soil of Eragrostis curvula and Miscanthus sinensis were collected from the Mizunashi River at Mt. Fugendake (Nagasaki Prefecture, Japan), where plant seeds and AMF including G. margarita CK had been introduced for reforestation after the occurrence of repeated pyroclastic flows. We detected the marker sequence from DNA preparations of E. curvula roots and Gigaspora spores in the rhizosphere. This clearly showed that the isolate occurred at both hyphal and sporal stages. It was shown that the isolate survived and developed a life cycle in the revegetation area for 4 years. It was confirmed that the method was effective for tracing the isolate in samples collected from field ecosystems.
-
a molecular marker diagnostic of a specific isolate of an arbuscular mycorrhizal fungus Gigaspora margarita
Fems Microbiology Letters, 2002Co-Authors: Kazuhira Yokoyama, Takahiro Tateishi, Takuya Marumoto, Masanori SaitoAbstract:To investigate the auto-ecology of a strain of Gigaspora margarita in a commercial inoculum, we found a pair of PCR primers amplifying a sequence of 235 bp diagnostic of the isolate. We designed an oligonucleotide probe based on the DNA sequence. The combination of PCR and the probing successfully detected the diagnostic sequence from both DNA preparations of single spores and colonized roots. This protocol enabled us to distinguish the isolate among several isolates from Japan, Nepal and the USA.
-
polyphosphates in intraradical and extraradical hyphae of an arbuscular mycorrhizal fungus Gigaspora margarita
Applied and Environmental Microbiology, 1999Co-Authors: Zakaria M Solaiman, Tatsuhiro Ezawa, Tomoko Kojima, Masanori SaitoAbstract:The amount of polyphosphate in the intraradical and extraradical hyphae of Gigaspora margarita was estimated from successive extractions with trichloroacetic acid (TCA), EDTA, and phenol-chloroform (PC). In the intraradical hyphae, most of the polyphosphate was present in TCA- and EDTA-soluble (short-chain and long-chain) fractions, whereas most of the polyphosphate in the extraradical hyphae was present in EDTA- and PC-soluble (long-chain and granular) fractions.
S E Smith - One of the best experts on this subject based on the ideXlab platform.
-
variation in rdna its sequences in glomus mosseae and Gigaspora margarita spores from a permanent pasture
Fungal Biology, 2000Co-Authors: Zaida Ines Antoniolli, D P Schachtman, K Ophelkeller, S E SmithAbstract:To study the genetic variability in Glomus mosseae and Gigaspora margarita sequence similarities of ITS regions of rDNA were analysed from spores collected from a permanent pasture and from pot cultures. PCR amplification with the primers ITS1 and ITS4 was performed and products were cloned and sequenced. The sequences from single spores of G. mosseae and Gi. margarita confirmed that there is variation in the ITS region in a single spore. Phenetic analysis of sequences from both species supported the morphological identification which placed the species into two separate groups. Through the analysis of these sequences an estimate of genetic diversity was derived which clearly showed that the three field spores of G. mosseae were at least 2–5 times more genetically diverse than one single spore (field) and a pool of spores (pot culture) of Gigaspora margarita. This demonstrates that a high degree of variation exists in this natural population of G. mosseae.
-
intersporal genetic variation of Gigaspora margarita a vesicular arbuscular mycorrhizal fungus revealed by m13 minisatellite primed pcr
Applied and Environmental Microbiology, 1997Co-Authors: A Zeze, K Ophelkeller, E Sulistyowati, Susan J Barker, S E SmithAbstract:Spores of vesicular arbuscular mycorrhizal (VAM) fungi contain thousands of nuclei. In order to understand the karyotic structure of a VAM fungus spore, the genetic variation of the first generation of spores from a VAM fungus (Gigaspora margarita) was examined. Spores originating from both single- and multispore inoculations of the species G. margarita were analyzed by M13 minisatellite-primed PCR. In both cases, different fingerprints were obtained from individual spores with few spores exhibiting similar fingerprints. These results can be explained only by a heterokaryotic status of the nuclear population within a spore.
Luisa Lanfranco - One of the best experts on this subject based on the ideXlab platform.
-
detection and identification of bacterial endosymbionts in arbuscular mycorrhizal fungi belonging to the family Gigasporaceae
Applied and Environmental Microbiology, 2000Co-Authors: Valeria Bianciotto, Erica Lumini, Paola Bonfante, Luisa Lanfranco, Daniela Minerdi, Silvia PerottoAbstract:Intracellular bacteria have been found previously in one isolate of the arbuscular mycorrhizal (AM) fungus Gigaspora margarita BEG 34. In this study, we extended our investigation to 11 fungal isolates obtained from different geographic areas and belonging to six different species of the family Gigasporaceae. With the exception of Gigaspora rosea, isolates of all of the AM species harbored bacteria, and their DNA could be PCR amplified with universal bacterial primers. Primers specific for the endosymbiotic bacteria of BEG 34 could also amplify spore DNA from four species. These specific primers were successfully used as probes for in situ hybridization of endobacteria in G. margarita spores. Neighbor-joining analysis of the 16S ribosomal DNA sequences obtained from isolates of Scutellospora persica, Scutellospora castanea, and G. margarita revealed a single, strongly supported branch nested in the genus Burkholderia.
-
expression of chitin synthase genes in the arbuscular mycorrhizal fungus Gigaspora margarita
New Phytologist, 1999Co-Authors: Luisa Lanfranco, Marta Vallino, Paola BonfanteAbstract:Genomic DNA from spores of the endomycorrhizal fungus Gigaspora margarita was amplified with two sets of degenerate primers designed on conserved regions of chitin synthase polypeptides. Three chitin synthase (chs) gene portions were identified: Gimchs1, Gimchs2 and Gimchs3, encoding one class II and two class IV chitin synthases, respectively. Gimchs1 and Gimchs3 transcripts were detected by reverse transcription polymerase chain reaction (RT-PCR) during root colonization, whereas none of three mRNAs was revealed during spore germination. The potential role of the genes expressed is discussed in the light of morphogenetic and signalling events.
R E Koske - One of the best experts on this subject based on the ideXlab platform.
-
attraction of germ tubes and germination of spores of the arbuscular mycorrhizal fungus Gigaspora gigantea in the presence of roots of maize exposed to different concentrations of phosphorus
Mycologia, 1995Co-Authors: S P Suriyapperuma, R E KoskeAbstract:AbstractChemotropism of germ tubes of Gigaspora gigantea to roots of four cultivars of Zea mays (differing in phosphorus-uptake efficiency) mediated by volatile exudates was examined in root-organ ...
-
Gigaspora gigantea parasitism of spores by fungi and actinomycetes
Fungal Biology, 1994Co-Authors: Pauju Lee, R E KoskeAbstract:Fungi and actinomycetes were isolated monthly for one year from spores of the arbuscular mycorrhizal fungus Gigaspora gigantea recovered from a maritime sand dune. Spores in four different stages of vigour (newly formed, greenish-yellow healthy; yellow, moribund, mottled with brown spots; brown; and dead, blackened and collapsed) were used for isolation. From 272 isolates cultured from crushed, surface-disinfected G. gigantea spores, 44 species of fungi and six actinomycete species were recovered. The five most frequently isolated organisms were Acremonium sp., Chrysosporium parvum, Exophiala werneckii, Trichoderma sp. and Verticillium sp. The species lists derived from the four spore types differed significantly. Thirty-one of the isolated species were tested for their ability to parasitise healthy G. gigantea spores and to invade spores killed by a hot water treatment. Twenty-two species could function as pathogens, forming internal projections (IP), fine radial canals (FRC) or both in the spore wall. IP were induced by Acremonium sp., Chrysosporium parvum, Cladosporium sp., Geomyces pannorum, Oidiodendron sp., Sporothrix sp., Verticillium sp. and by the actinomycetes Nocardia sp. and Streptomyces sp. The IP length was positively correlated with duration of exposure to the parasites. In the bioassay, both IP and FRC were formed by live spores, while heat-killed spores possessed only FRC after penetration by the test microorganisms. Pathogenicity differed among the parasites and was greatest for Verticillium and Acremonium .