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Helmut König - One of the best experts on this subject based on the ideXlab platform.
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sugiyamaella mastotermitis sp nov and papiliotrema odontotermitis f a sp nov from the gut of the termites Mastotermes darwiniensis and odontotermes obesus
International Journal of Systematic and Evolutionary Microbiology, 2016Co-Authors: Steffen Handel, Andrey Yurkov, Tengfei Wang, Helmut KönigAbstract:Two novel yeast species were isolated from the guts of two different termite species. A new member of the genus Sugiyamaella was isolated from the hindgut and nest material of the lower Australian termite Mastotermes darwiniensis. The second novel yeast species, isolated from the higher termite Odontotermes obesus, was identified as a member of the genus Papiliotrema. Both yeast species were able to hydrolyse xylan, methylumbelliferyl β-xylobiose and methylumbelliferyl β-xylotriose. The ability to debranch different hemicellulose side chains and growth without the addition of external vitamins was observed. A symbiotic role of the novel yeast species is indicated, especially in respect to xylan degradation and the production of vitamins. Here, we describe these species as Sugiyamaella mastotermitis sp. nov., MycoBank 816574 (type strain MD39VT=DSM 100793T=CBS 14182T), and Papiliotrema odontotermitis f.a., sp. nov., MycoBank 816575 (type strain OO5T=DSM 100791T=CBS 14181T). Additionally, we transfer Candida qingdaonensis to the genus Sugiyamaella and propose the following combination: Sugiyamaella qingdaonensis f.a., comb. nov., MycoBank 816576.
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Isolation of methanotrophic bacteria from termite gut
Microbiological Research, 2015Co-Authors: Julia Reuß, Jan Dr. Küver, Andreas Rabenstein, Stefan Droge, Reinhard Rachel, Peter Kämpfer, Helmut KönigAbstract:The guts of termites feature suitable conditions for methane oxidizing bacteria (MOB) with their permanent production of CH4 and constant supply of O2via tracheae. In this study, we have isolated MOB from the gut contents of the termites Incisitermes marginipennis, Mastotermes darwiniensis, and Neotermes castaneus for the first time. The existence of MOB was indicated by detecting pmoA, the gene for the particulate methane monooxygenase, in the DNA of gut contents. Fluorescence in situ hybridization and quantitative real-time polymerase chain reaction supported those findings. The MOB cell titer was determined to be 102–103 per gut. Analyses of the 16S rDNA from isolates indicated close similarity to the genus Methylocystis. After various physiological tests and fingerprinting methods, no exact match to a known species was obtained, indicating the isolation of new MOB species. However, MALDI-TOF MS analyses revealed a close relationship to Methylocystis bryophila and Methylocystis parvus.
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production of methyl mercury in the gut of the australian termite Mastotermes darwiniensis
Journal of Applied Entomology, 2008Co-Authors: Uta Limper, Brigitte Knopf, Helmut KönigAbstract:Animals are often exposed to or can ingest heavy metals along with their food. Therefore, we tested whether the hindgut microbiota of Mastotermes darwiniensis possesses the capability to form methyl mercury. The termite M. darwiniensis (Isoptera) was fed with saw dust containing different concentrations of inorganic mercury. Methyl mercury was determined by purge-and-trap capillary gas chromatography-atom fluorescence spectrometry (CGC-AFS) using ethyl mercury chloride as the internal standard. Total mercury concentrations were determined in the termite tissue by inductive coupled plasma-isotope dilution mass spectrometry (ICP-IDMS) after microwave-assisted digestion. The obtained results showed in vivo methyl mercury production in terrestrial insects for the first time. Desulfovibrio intestinalis isolated from M. darwiniensis was identified as a biomethylating species of the intestinal microbiota.
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the flagellates of the australian termite Mastotermes darwiniensis identification of their symbiotic bacteria and cellulases
Symbiosis, 2007Co-Authors: Helmut König, Marika Wenzel, Manfred Berchtold, Alfred Breunig, Stefan Droge, Renate Radek, Jürgen FrÖhlich, Peter Pfeiffer, Li Li, G BrugerolleAbstract:Termites are among the most important wood- and litter-feeding insects. The gut microbiota plays an indispensable role in the digestion of food. They can include Bacteria, Archaea, flagellates, yeasts, and fungi. The unique flagellates of the termite gut belong to the Preaxostyla (Oxymonadida) and Parabasalia (Cristamonadida, Spirotrichonymphida, Trichomonadida, Trichonymphida), which have branched off very early in the evolution of the eukaryotes. The termite Mastotermes darwiniensis is the only species of the most primitive termite family Mastotermitidae. It harbors four large flagellate species in the hindgut: the cristamonads Koruga bonita, Deltotrichonympha nana, Deltotrichonympha operculata and Mixotricha paradoxa. Two small flagellate species also thrive in the intestine: the cristamonad Metadevescovina extranea and the trichomonad Pentatrichomonoides scroa. The flagellates themselves harbor extracellular and intracellular prokaryotes. From cell extracts of the not yet culturable symbiotic flagellates two endoglucanases with a similar apparent molecular mass of approximately 36 kD have been isolated. They exhibited significant homology to cellulases of termite origin. The corresponding genes were detected not in the mRNA pool of the flagellates, but in the salivary glands of Mastotermes darwiniensis. These results indicated that the intestinal flagellates of Mastotermes darwiniensis also use the termite's cellulases for cellulose hydrolysis. In total extracts of the intestine of wild termites also three cellulases were detected, which should originate from flagellates.
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in vitro and in vivo sulfate reduction in the gut contents of the termite Mastotermes darwiniensis and the rose chafer pachnoda marginata
Journal of General and Applied Microbiology, 2005Co-Authors: Stefan Droge, Uta Limper, Farahnaz Emtiazi, Inge Schonig, Natalija Pavlus, Oliver Drzyzga, Ulrich Fischer, Helmut KönigAbstract:Sulfate-reducing bacteria (SRB) from termites have been assigned to the genus Desulfovibrio. Desulfovibrio intestinalis lives in the gut of the Australian termite Mastotermes darwiniensis. For the first time we were able to enrich and identify a sulfate-reducing bacterium from the gut of the rose-chafer Pachnoda marginata, which showed the highest 16S rDNA sequence identity (93%) to Desulfovibrio intestinalis and Desulfovibrio strain STL1. Compared to Mastotermes darwiniensis (1×107 cells of SRB per ml gut contents), sulfate-reducing bacteria occurred in higher numbers in the gut contents of Pachnoda marginata reaching cell titers of up to 2×108 cells per ml gut contents. In vitro sulfate reduction rates were determined with SRB from the gut contents of the termite Mastotermes darwiniensis and the beetle Pachnoda marginata. Due to the higher cell titer, the sulfate reduction rate of Pachnoda marginata was 104 nmol×h−1×ml−1 and therefore, 21 times higher than that of Mastotermes darwiniensis. In addition, we detected in vivo sulfate reduction in Mastotermes darwiniensis, which indicates that sulfate reducers play an active role in the sulfur metabolism in the termite gut.
Manfred Berchtold - One of the best experts on this subject based on the ideXlab platform.
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the flagellates of the australian termite Mastotermes darwiniensis identification of their symbiotic bacteria and cellulases
Symbiosis, 2007Co-Authors: Helmut König, Marika Wenzel, Manfred Berchtold, Alfred Breunig, Stefan Droge, Renate Radek, Jürgen FrÖhlich, Peter Pfeiffer, Li Li, G BrugerolleAbstract:Termites are among the most important wood- and litter-feeding insects. The gut microbiota plays an indispensable role in the digestion of food. They can include Bacteria, Archaea, flagellates, yeasts, and fungi. The unique flagellates of the termite gut belong to the Preaxostyla (Oxymonadida) and Parabasalia (Cristamonadida, Spirotrichonymphida, Trichomonadida, Trichonymphida), which have branched off very early in the evolution of the eukaryotes. The termite Mastotermes darwiniensis is the only species of the most primitive termite family Mastotermitidae. It harbors four large flagellate species in the hindgut: the cristamonads Koruga bonita, Deltotrichonympha nana, Deltotrichonympha operculata and Mixotricha paradoxa. Two small flagellate species also thrive in the intestine: the cristamonad Metadevescovina extranea and the trichomonad Pentatrichomonoides scroa. The flagellates themselves harbor extracellular and intracellular prokaryotes. From cell extracts of the not yet culturable symbiotic flagellates two endoglucanases with a similar apparent molecular mass of approximately 36 kD have been isolated. They exhibited significant homology to cellulases of termite origin. The corresponding genes were detected not in the mRNA pool of the flagellates, but in the salivary glands of Mastotermes darwiniensis. These results indicated that the intestinal flagellates of Mastotermes darwiniensis also use the termite's cellulases for cellulose hydrolysis. In total extracts of the intestine of wild termites also three cellulases were detected, which should originate from flagellates.
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phylogenetic analysis and in situ identification of uncultivated spirochetes from the hindgut of the termite Mastotermes darwiniensis
Systematic and Applied Microbiology, 1996Co-Authors: Manfred Berchtold, Helmut KönigAbstract:Summary Different small subunit ribosomal DNA (SSU rDNA) sequences of uncultivated spirochetes from the hindgut of the termite Mastotermes darwiniensis were determined and phylogenetically analysed. Starting with DNA isolated from hindgut contents we amplified SSU rDNA coding regions by PCR using bacteria- and spirochete-specific primers, respectively. Cloning and sequencing of the amplification products re-sulted in 11 different spirochetal SSU rDNA sequences with similarity values of 81.8% to 99.0% to each other. Phylogenetic trees showed that the obtained sequences are related to the genus Treponema with 84.0% to 91.1% similarity to Treponema spec. H1 and Spirochaeta stenostrepta as their nearest relatives among the cultivated spirochetes. Using fluorescence in situ hybridisation one of the SSU rDNA sequences could be assigned to a large spirochete. So at least one of the large hindgut spirochetes unique in termite hindguts and assigned to the genera Hollandina , Pillotina , Clevelandina or Diplocalyx phylogenetically belongs to the treponeme cluster of spirochetes.
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16s rdna sequence and phylogenetic position of an uncultivated spirochete from the hindgut of the termite Mastotermes darwiniensis froggatt
Fems Microbiology Letters, 1994Co-Authors: Manfred Berchtold, Wolfgang Ludwig, Helmut KönigAbstract:We have analyzed the 16S rDNA sequence and the phylogenetic position of an uncultivated spirochete from the hindgut contents of the Australian termite Mastotermes darwiniensis Froggatt. The 16S rRNA genes of bacteria from the hindgut contents of Mastotermes darwiniensis were amplified by polymerase chain reaction. The amplification products were cloned and sequenced. The sequences were compared to known homologous primary structures. Two of the clones (MDS1 and MDS3) had an insert of 1498 nucleotides showing typical signatures of spirochete 16S rRNA sequences. The sequences of the two clones were most similar to the 16S rRNA sequence of Spirochaeta stenostrepta (89.8%) and Treponema sp. strain H1 (90.7%). Phylogenetical analysis positioned the hindgut spirochete sequence with that of the free-living anaerobic Spirochaeta stenostrepta and Treponema sp. strain H1 as its nearest relatives within the cluster of the spirochetes. We conclude that the analyzed SSU rDNA sequences originate from a spirochete related to the genus Treponema. It is possibly one of the uncultivated unique spirochetes symbiotic in termite hindguts.
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The phylogenetic position ofDimastigella trypaniformis within the parasitic kinetoplastids
Parasitology Research, 1994Co-Authors: Manfred Berchtold, Alfred Breunig, G Brugerolle, H Philippe, H. KönigAbstract:The nuclear 16S-like rRNA coding regions of two strains of the kinetoplastid flagellate Dimastigella trypaniformis Sandon (strain Ulm and strain Glasgow) were sequenced and phylogenetically analyzed. Strain Ulm was isolated from the hindgut contents of the Australian termite Mastotermes darwiniensis Frogatt, whereas strain Glasgow originates from a soil sample in Scotland. After preparation of genomic DNA the 16S-like rRNA coding regions were amplified using polymerase chain reaction (PCR) technology. The amplification products were cloned in a plasmid vector and sequenced according to standard methods. The sequence of the 16S-like rRNA coding region of strain Ulm differs less than 2% from the sequence of strain glasgow, indicating that the two strains are most probably members of one species. Phylogenetic analysis of the sequence data positioned D. trypaniformis Sandon as a deep branching lineage near the root of the kinetoplastid group of flagellates.
Michael Lenz - One of the best experts on this subject based on the ideXlab platform.
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ability of field populations of coptotermes spp reticulitermes flavipes and Mastotermes darwiniensis isoptera rhinotermitidae mastotermitidae to damage plastic cable sheathings
Journal of Economic Entomology, 2013Co-Authors: Michael Lenz, B M Kard, Edward D Freytag, Junhong Zhong, Boonhoi Yeoh, Kenneth S Brown, Theodore A. Evans, James W Creffield, Tsuyoshi Yoshimura, Kunio TsunodaAbstract:ABSTRACT A comparative field study was conducted to evaluate the ability of subterranean termites to damage a set of four different plastic materials (cable sheathings) exposed below- and above-ground. Eight pest species from six countries were included, viz., Coptotermes formosanus (Shiraki) in China, Japan, and the United States; Coptotermes gestroi (Wasmann) in Thailand and Malaysia; Coptotermes curvignathus (Holmgren) and Coptotermes kalshoveni (Kemner) in Malaysia; Coptotermes acinaciformis (Froggatt) with two forms of the species complex and Mastotermes darwiniensis (Froggatt) in Australia; and Reticulitermes flavipes (Kollar) in the United States. Termite species were separated into four tiers relative to decreasing ability to damage plastics. The first tier, most damaging, included C. acinaciformis, mound-building form, and M. darwiniensis, both from tropical Australia. The second tier included C. acinaciformis, tree-nesting form, from temperate Australia and C. kalshoveni from Southeast Asia. The...
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Phylogenetic tree of GHF7. Numbered clones (for example SM2734B07) are cellulase genes identified in this study from the symbiotic protists of termites.
2013Co-Authors: Nemuri Todaka, Christine A Nalepa, Michael Lenz, Tetsushi Inoue, Kanako Saita, Moriya Ohkuma, Toshiaki Kudo, Shigeharu MoriyaAbstract:Letters in parentheses after each clone denote host termite species (Rs = Reticulitermes speratus, Nk = Neotermes koshunensis, Hs = Hodotermopsis sjostedti, Md = Mastotermes darwiniensis, Cp = Cryptocercus punctulatus). Accession numbers of reference sequences are denoted after species names.
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Phylogenetic tree of GHF11. Numbered clones (for example SM2038A64) are cellulase genes identified in this study from the symbiotic protists of termites.
2013Co-Authors: Nemuri Todaka, Christine A Nalepa, Michael Lenz, Tetsushi Inoue, Kanako Saita, Moriya Ohkuma, Toshiaki Kudo, Shigeharu MoriyaAbstract:Letters in paretheses after each clone denote host termite species (Rs = Reticulitermes speratus, Nk = Neotermes koshunensis, Hs = Hodotermopsis sjostedti, Md = Mastotermes darwiniensis, Cp = Cryptocercus punctulatus). Accession numbers of reference sequences are denoted after species names.
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Phylogenetic tree of GHF45. Numbered clones (for example NT0285A89) are cellulase genes identified in this study from the symbiotic protists of termites.
2013Co-Authors: Nemuri Todaka, Christine A Nalepa, Michael Lenz, Tetsushi Inoue, Kanako Saita, Moriya Ohkuma, Toshiaki Kudo, Shigeharu MoriyaAbstract:Letters in paretheses after each clone denote host termite species (Rs = Reticulitermes speratus, Nk = Neotermes koshunensis, Hs = Hodotermopsis sjostedti, Md = Mastotermes darwiniensis, Cp = Cryptocercus punctulatus). Accession numbers of reference sequences are denoted after species names.
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Phylogenetic tree of GHF5. Numbered clones (for example SM2030B48) are cellulase genes identified in this study from the symbiotic protists of termites.
2013Co-Authors: Nemuri Todaka, Christine A Nalepa, Michael Lenz, Tetsushi Inoue, Kanako Saita, Moriya Ohkuma, Toshiaki Kudo, Shigeharu MoriyaAbstract:Letters in parentheses after each clone denote host termite species (Rs = Reticulitermes speratus, Nk = Neotermes koshunensis, Hs = Hodotermopsis sjostedti, Md = Mastotermes darwiniensis, Cp = Cryptocercus punctulatus). Accession numbers of reference sequences are denoted after species names. SF are indicated the sub-family (21) and SSFs are indicated sub-sub families that were used in Fig. 3. In sub-family 1 and 2, gray boxed sub-sub-family indicated that composed by symbiont's sequences and other sub-sub-families composed by bacterial sequences.
Rossiter H Crozier - One of the best experts on this subject based on the ideXlab platform.
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association between caste and genotype in the termite Mastotermes darwiniensis froggatt isoptera mastotermitidae
Australian Journal of Entomology, 2003Co-Authors: Michael A. D. Goodisman, Rossiter H CrozierAbstract:Termite workers and soldiers differ markedly in their morphology and behaviour. We sought evidence for genetic influences on caste determination in the giant northern termite, Mastotermes darwiniensis, by investigating if workers and soldiers from the same colony differed genetically. The genotypes of 795 termites from 11 distinct colonies were assayed at six polymorphic microsatellite loci. We found that the multilocus genotypes of workers and soldiers from 8 of the 11 colonies did not differ significantly. Thus, the majority of the data provided no evidence for a genetic association with caste in workers and soldiers of M. darwiniensis. However, the genotype frequencies of workers and soldiers from three colonies differed, suggesting that genotype is occasionally associated with caste in this species. The genetic differentiation of castes within these colonies could reflect differences in the propensities of termites with distinct genotypes to develop into particular castes and provide a selective advantage to colonies headed by multiple reproductives.
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Isolation and characterization of a termite transferrin gene up-regulated on infection.
Insect Molecular Biology, 2003Co-Authors: Graham J. Thompson, Y. Ching Crozier, Rossiter H CrozierAbstract:PCR-based subtractive hybridization was used to isolate genes preferentially expressed in a termite (Mastotermes darwiniensis) following exposure to an entomopathogenic fungus. The subtraction procedure yielded a cDNA clone encoding a putative transferrin that, when sequenced to its ends, is the largest (728 amino acids) for any insect transferrin characterized to date. Cysteines and residues comprising putative iron-binding sites are conserved in both N- and C-terminal lobes, suggesting structural and functional similarity to diferric vertebrate transferrins. A quantitative PCR assay confirmed a significant increase in transferrin expression following infection, suggesting its up-regulation is part of the innate immune response. However, codon-based tests for selection among known insect transferrins revealed only a small proportion of codon-sites positively selected. Thus, unlike certain vertebrate transferrin lineages, no widespread evidence for pathogen-mediated positive selection was detected at this locus.
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population and colony genetic structure of the primitive termite Mastotermes darwiniensis
Evolution, 2002Co-Authors: Michael A. D. Goodisman, Rossiter H CrozierAbstract:The termite Mastotermes darwiniensisis the sole extant member of its family and occupies the basal position in the phylogeny of the eusocial order Isoptera. In this study, we investigated the micro- and macrogeographic genetic structure of M. darwiniensis in its native range in Australia. A total of 1591 workers were sampled from 136 infested trees in 24 locales. Each locale was separated by 2-350 km, and these locales were found within two broader geographic regions approximately 1500 km apart. The multilocus genotypes of all termites were assayed at six polymorphic microsatellite loci. The genetic data indicated that colonies typically fed on multiple trees within locales and extended over linear distances of up to 320 m. Single colonies were frequently headed by multiple reproductives. Workers were highly related (r 5 0.40) and substantially inbred (f 5 0.10). Thus, M. darwiniensis colonies are characterized by the input of alleles from multiple reproductives, which sometimes engage in consanguineous matings. Our analyses of population genetic structure above the level of the colony indicated that locales and regions were significantly dif- ferentiated (ulocale 5 0.50, uregion 5 0.37). Moreover, locales showed a pattern of genetic isolation by distance within regions. Thus, M. darwiniensispopulations display restricted gene flow over moderate geographic distances. We suggest that the genetic patterns displayed by M. darwiniensis result primarily from selective pressures acting to maintain high relatedness among colonymates while allowing colonies to grow rapidly and dominate local habitats.
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microsatellite markers in the primitive termite Mastotermes darwiniensis
Molecular Ecology Notes, 2001Co-Authors: Michael A. D. Goodisman, John G Ewen, Theodore A. Evans, Rossiter H CrozierAbstract:We developed 10 microsatellite loci in the primitive termite Mastotermes darwiniensis. The number of alleles per locus ranged from four to 15, and the expected heterozygosites spanned from 0.21 to 0.90, in a sample of 40 workers collected from the Northern Territory, Australia. We also determined that only two loci amplified in five other termite species. The low frequency of cross-amplification probably resulted from the high level of phylogenetic divergence between M. darwiniensis and the other taxa. Thus, although the loci are not widely applicable, they should prove effective in elucidating the genetic structure of M. darwiniensis populations.
Lynn Margulis - One of the best experts on this subject based on the ideXlab platform.
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Spirochete attachment ultrastructure: Implications for the origin and evolution of cilia.
The Biological Bulletin, 2010Co-Authors: Andrew M. Wier, Michael F. Dolan, James Macallister, Luciano Sacchi, Claudio Bandi, Lynn MargulisAbstract:The fine structure of spirochete attachments to the plasma membrane of anaerobic protists displays variations here interpreted as legacies of an evolutionary sequence analogous to that from free-living spirochetes to undulipodia (eukaryotic “flagella” and homologous structures). Attached spirochetes form a vestment, a wriggling fringe of motile cells at the edge of the plasma membrane of unidentified cellulolytic protist cells in the hypertrophied hindgut of the digestive system of Mastotermes darwiniensis, the large wood-feeding termite from northern Australia. From the membrane extend both undulipodia and a complex of comparably sized (10–12 μm × 0.2–0.3 μm) ectosymbiotic spirochetes that resembles unruly ciliated epithelium. In the intestines are helical (swimming) and round-body morphotypes. Round bodies (RBs) are slow or immotile spirochetes, propagules known to revert to typical swimming helices under culture conditions favorable for growth. The surfaces of both the spirochete gram-negative eubacter...
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Spirochete and Protist Symbionts of a Termite (Mastotermes Electrodominicus) in Miocene Amber
Proceedings of the National Academy of Sciences of the United States of America, 2002Co-Authors: Andrew Wier, Michael A. Dolan, David A. Grimaldi, Jorge Wagensberg, Ricardo Guerrero, Lynn MargulisAbstract:Extraordinary preservation in amber of the Miocene termite Mastotermes electrodominicus has led to the discovery of fossil symbiotic microbes. Spirochete bacteria and wood-digesting protists were identified in the intestinal tissue of the insect. Fossil wood (xylem: developing vessel-element cells, fibers, pit connections), protists (most likely xylophagic amitochondriates), an endospore (probably of the filamentous intestinal bacterium Arthromitus = Bacillus), and large spirochetes were seen in thin section by light and transmission electron microscopy. The intestinal microbiota of the living termite Mastotermes darwiniensis, a genus now restricted to northern Australia, markedly resembles that preserved in amber. This is a direct observation of a 20-million-year-old xylophagus termite fossil microbial community.