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Christoph Scheidegger - One of the best experts on this subject based on the ideXlab platform.
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genetic diversity and structure of the epiphytic foliose lichen Lobaria pindarensis in the himalayas depends on elevation
Fungal Ecology, 2019Co-Authors: Shiva Devkota, Silke Werth, Ram Prasad Chaudhary, Christoph ScheideggerAbstract:Abstract The epiphytic lichen Lobaria pindarensis is a Himalayan endemic species with little information on distribution, genetic diversity and structural complexity. During an intensive survey in the Nepal Himalayas, we collected 1256 thallus fragments from 45 phorophyte species to study their distribution and population genetics along an elevational gradient. We quantified genetic diversity and population structure of each symbiont at 17 fungus specific and 9 alga specific microsatellite loci. The Bayesian clustering identified three and two distinct gene pools for mycobiont and photobiont. We found that genetic diversity, allelic richness and gene pool composition and distribution were significantly influenced by elevation. We discovered both clonally and sexually reproduced repeated genotypes of the symbionts.
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Multiple mating events and spermatia-mediated gene flow in the lichen-forming fungus Lobaria pulmonaria
Herzogia, 2016Co-Authors: Christine Keller, Christoph ScheideggerAbstract:Abstract: Keller, C. & Scheidegger, C. 2016. Multiple mating events and spermatia-mediated gene flow in the lichen-forming fungus Lobaria pulmonaria. — Herzogia 29: 435–450. Lichen-forming fungi have developed combined reproductive strategies that involve both sexual and asexual propagules, which are produced in varying frequencies over space and time. Lobaria pulmonaria reveals the characteristic traits of genetically diverse, fully recombinant populations, despite the generally rare occurrence of sexual reproductive structures. This study aimed at investigating the genetic diversity of the progenies of single apothecia of L. pulmonaria from different populations. Because the percentage of germinating ascospores is often very small and single spore cultures are thus difficult to obtain, we tested a protocol of DNA isolation from a multispore fraction and identified the alleles of three fungus-specific microsatellite markers. Multispore samples analysed from single apothecia revealed two to three differen...
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multi gene phylogeny of the genus Lobaria evidence of species pair and allopatric cryptic speciation in east asia
American Journal of Botany, 2015Co-Authors: Carolina Cornejo, Christoph ScheideggerAbstract:PREMISE OF THE STUDY Accurate species delimitation has critical implications for ecological and conservation studies. The lichen genus Lobaria is widely distributed in old-growth forests. Particularly in East Asia, this genus includes many rare and poorly known taxa that are circumscribed as morpho- or chemospecies, as well as species-pairs. METHODS To critically examine the relationships between species identified via morphological and chemical criteria, phylogenetic species recognition (PSR) was applied to the genus Lobaria. Morphological and chemical patterns of 87 individuals were examined and three independent nuclear loci were sequenced. The East Asian L. meridionalis-group was additionally studied using split decomposition and haplotype network analysis. KEY RESULTS The genus Lobaria and most of its species were strongly supported statistically. Split decomposition and haplotype networks suggest complex evolutionary histories of species within the East Asian L. meridionalis-group. CONCLUSIONS Phylogenetic analyses confirmed the monophyly of the genus Lobaria, including L. anomala. Within Lobaria, three major clades were found. These clades associate with different photobionts and comprise 18 known species and 5 undescribed species. Several chemical compounds were found to be neither stable nor invariant characters. Some taxa of the L. meridionalis-group appear to be monophyletic but remain as allopatric cryptic species. In three clades, this study found evidence for diversification processes between isidiate and nonisidiate specimens (species-pair). These findings are discussed in the context of evolutionary hypotheses for speciation processes.
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characterization of microsatellite loci in the himalayan lichen fungus Lobaria pindarensis Lobariaceae
Applications in Plant Sciences, 2014Co-Authors: Shiva Devkota, Carolina Cornejo, Silke Werth, Ram Prasad Chaudhary, Christoph ScheideggerAbstract:Premise of the study: Microsatellite loci were developed for the rare, Himalayan, endemic haploid lichen fungus, Lobaria pindarensis, to study its population subdivision and the species' response to forest disturbance and fragmentation. Methods and Results: We developed 18 polymorphic microsatellite markers using 454 pyrosequencing data and assessed them in 109 individuals. The number of alleles per locus ranged from three to 11 with an average of 6.9. Nei's unbiased gene diversity, averaged over loci, ranged from 0.514 to 0.685 in the three populations studied. The cross-amplification success with related species (L. chinensis, L. gyrophorica, L. isidiophora, L. orientalis, L. pulmonaria, L. spathulata, and Lobaria sp.) was generally high and decreased with decreasing relationship to L. pindarensis. Conclusions: The new markers will allow the study of genetic diversity and differentiation within L. pindarensis across its distribution. Moreover, they will enable us to study the effects of forest managemen...
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Characterization of microsatellite loci in the lichen fungus Lobaria pulmonaria (Lobariaceae)
Applications in Plant Sciences, 2013Co-Authors: Silke Werth, Carolina Cornejo, Christoph ScheideggerAbstract:Premise of the study: Microsatellite loci were developed for the threatened haploid lichen fungus Lobaria pulmonaria to increase the resolution to identify clonal individuals, and to study its population subdivision. Methods and Results: We developed 14 microsatellite markers from 454 DNA sequencing data of L. pulmonaria and tested for cross-amplification with L. immixta and L. macaronesica. The number of alleles per locus ranged from two to 23. Nei's unbiased gene diversity, averaged over loci, ranged from 0.434 to 0.517 in the three studied populations. Conclusions: The new markers will increase the genetic resolution in studies that aim at disentangling clones in L. pulmonaria and may be useful for closely related species within Lobaria sect. Lobaria.
Yngvar Gauslaa - One of the best experts on this subject based on the ideXlab platform.
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Short- and long-term freezing effects in a coastal (Lobaria virens) versus a widespread lichen (L. pulmonaria).
Cryobiology, 2018Co-Authors: Knut Asbjørn Solhaug, Dipa Paul Chowdhury, Yngvar GauslaaAbstract:Abstract Lichens are considered freezing tolerant, although few species have been tested. Growth, a robust measure of fitness integrating processes in all partners of a lichen thallus, has not yet been used as a viability measure after freezing. We compared relative growth rates (RGR) after freezing with short-term viability measures of photo- and mycobiont functions in the coastal Lobaria virens and the widespread L. pulmonaria to test the hypothesis that low temperature shapes the coastal distribution of L. virens. Hydrated thalli from sympatric populations were subjected to freezing at −10, −20 and −40 °C for 5 h. The rate of cooling and subsequent warming was 5 °C h−1. Short-term viability measures of photobiont (maximal photosystem II efficiency, effective PSII yield) and mycobiont viability (conductivity index), as well as subsequent RGR, were assessed. The exotherms showed that L. virens froze at −3 °C; L. pulmonaria, at −4 °C. Freezing significantly impaired short-term viability measures of both photo- and mycobiont, particularly in the coastal species. Lobaria pulmonaria grew 2.1 times faster than L. virens, but the short-term damage after one freezing event did not affect the long-term RGR in any species. Thereby, short-term responses were impaired by freezing, long-term responses were not. While the lacking RGR-responses to freezing suggest that freezing tolerance does not shape the coastal distribution of L. virens, the significant reported adverse short-term effects in L. virens may be aggravated by repeated freezing-thawing cycles in cold winters. In such a perspective, repeated freezing may eventually lead to reduced long-term fitness in L. virens.
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hydration traits in cephalolichen members of the epiphytic old forest genus Lobaria s lat
Lichenologist, 2017Co-Authors: Sara Longinotti, Knut Asbjørn Solhaug, Yngvar GauslaaAbstract:This study aims to quantify the size-dependency of important hydration traits in Lobaria amplissima, L. pulmonaria and L. virens sampled in sympatric populations on deciduous tree trunks in southern Norway, and to discuss possible implications of species-specific traits for the ecological niches of these old forest cephalolichens. Traits measured were thallus size (area and mass), specific thallus mass (STM), internal (WHCinternal) and external water-holding capacity (WHCexternal), and water content (WC) after shaking and after blotting. Lobaria amplissima had the highest WHCinternal, 2·6 times higher than L. pulmonaria with the lowest WHCinternal. WHCinternal, driven by STM, strongly depended on size. WHCexternal was 28% (L. virens) to 47% (L. pulmonaria) of the WHCinternal. Unlike WHCinternal, WHCexternal did not depend on thallus area, meaning that WHCexternal is proportionally higher for smaller compared with larger thalli. The most widespread species, L. pulmonaria, benefits from a flexible hydration strategy due to low STM, facilitating the use of more diverse water sources than the other two species that depend more on rain, particularly L. amplissima with the highest STM and thus relatively high WHCinternal. For L. virens, a combination of less specialized hydration traits and a low tolerance to higher light intensity probably jeopardizes its survival outside rainforest habitats.
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Fungal tissue per se is stronger as a UV-B screen than secondary fungal extrolites in Lobaria pulmonaria
Fungal Ecology, 2017Co-Authors: Yngvar Gauslaa, Azharul Alam, Pierre-louis Lucas, Dipa Paul Chowdhury, Knut Asbjørn SolhaugAbstract:Abstract To test the hypotheses that (1) protective mycobiont tissues and/or (2) medullary UV-B-absorbing carbon-based secondary compounds (CBSCs) protect lichen photobionts against UV-B radiation, we quantified cortical UV-transmittance and ran a three-way factorial lab experiment with (1) three UV radiation regimes, (2) photobiont layers with/without a screening cortex, and (3) with natural/reduced CBSC-concentration. We used melanin-deficient Lobaria pulmonaria from shaded forests. Maximum photochemical efficiency of photosystem II ( F v/ F m) in photobionts inside thalli with natural CBSC-concentrations was not affected by any UV-regime, consistent with close to 0% measured cortical transmittance of wavelengths P P P = 0.001), mainly affecting exposed photobiont layers given short-wavelength UV radiation. Based on these findings, we conclude that the primary role of extrolites in L. pulmonaria is not to screen excess solar radiation.
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relative growth rates and secondary compounds in epiphytic lichens along canopy height gradients in forest gaps and meadows in inland british columbia
Botany, 2015Co-Authors: Massimo Bidussi, Yngvar GauslaaAbstract:We explore relative growth rates (RGRs) and carbon-based secondary compounds (CBSCs) in epiphytic lichens along height-above-the-ground gradients. The chlorolichen (Letharia vulpina (L.) Hue), the cephalolichen (Lobaria pulmonaria (L.) Hoffm.), and the cyanolichens (Lobaria hallii (Tuck.) Zahlbr., Nephroma helveticum Ach.) were attached to branches at 0.5–3.0 m heights of young spruce trees transplanted for 1 year in forest gaps and in old meadows of an inland valley in British Columbia. Cephalolichen and cyanolichen RGRs were highest in forest gaps, whereas the chlorolichen grew faster in meadows with twice as much light as forest gaps. Transplantation height did not influence lichen temperature or RGRs, despite height-dependent light increases. CBSCs were highest in the chlorolichen (13%), followed by the cephalolichen (5%) and the cyanolichens (1% and 0%). CBSC concentrations increased with thallus size, and were significantly higher in forest gaps mainly for L. pulmonaria. Only one minor CBSC in each ...
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seasonal and spatial variation in carbon based secondary compounds in green algal and cyanobacterial members of the epiphytic lichen genus Lobaria
Phytochemistry, 2013Co-Authors: Yngvar Gauslaa, Knut Asbjørn Solhaug, Johan Asplund, Massimo Bidussi, Per LarssonAbstract:Acetone-extractable carbon based secondary compounds (CBSCs) were quantified in two epiphytic lichens to study possible effects of external factors (season and aspect) on secondary chemistry and to relate defense investments to biomass growth and changes in specific thallus mass (STM). At the end of four separate annual cycles starting in each of the four seasons, the cyanolichen Lobaria scrobiculata and the cephalolichen Lobaria pulmonaria (green algae as the primary photobiont and with localized Nostoc in internal cephalodia) were monitored in their natural forest habitats and after being transplanted at three contrasting aspects in open sites. Season strongly influenced most CBSCs. Medullary CBSCs in both species were twice as high in summer as in winter. Aspect hardly affected major CBSCs, whereas transplantation from forest to clear-cut slightly reduced these compounds. No major CBSCs in any species showed a trade-off with growth rate. Dry matter- as well as thallus area-based medullary CBSC contents increased with STM. The cortical usnic acid strongly increased with growth rate and followed spatial, but not seasonal variations in light exposure. Maximal CBSC levels during seasons with most herbivores is consistent with the hypothesis inferring that herbivory is a major selective force for CBSCs. Lack of trade-off between growth and defence investments suggests that these two processes do not compete for photosynthates.
Silke Werth - One of the best experts on this subject based on the ideXlab platform.
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genetic diversity and structure of the epiphytic foliose lichen Lobaria pindarensis in the himalayas depends on elevation
Fungal Ecology, 2019Co-Authors: Shiva Devkota, Silke Werth, Ram Prasad Chaudhary, Christoph ScheideggerAbstract:Abstract The epiphytic lichen Lobaria pindarensis is a Himalayan endemic species with little information on distribution, genetic diversity and structural complexity. During an intensive survey in the Nepal Himalayas, we collected 1256 thallus fragments from 45 phorophyte species to study their distribution and population genetics along an elevational gradient. We quantified genetic diversity and population structure of each symbiont at 17 fungus specific and 9 alga specific microsatellite loci. The Bayesian clustering identified three and two distinct gene pools for mycobiont and photobiont. We found that genetic diversity, allelic richness and gene pool composition and distribution were significantly influenced by elevation. We discovered both clonally and sexually reproduced repeated genotypes of the symbionts.
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intrathalline distribution of two lichenicolous fungi on Lobaria hosts an analysis based on quantitative real time pcr
Herzogia, 2017Co-Authors: Timna Claire Bergmann, Silke WerthAbstract:Abstract: Bergmann, T. C. & Werth, S. 2017. Intrathalline distribution of two lichenicolous fungi on Lobaria hosts — an analysis based on quantitative Real-Time PCR. — Herzogia 30: 253–271. The biology of lichenicolous fungi is still poorly known, including intrathalline hyphal distribution patterns and the density of hyphae these fungi may form within lichen thalli. Since the hyphae of most lichenicolous fungi cannot be morphologically distinguished from those of the lichen mycobiont, we used quantitative Real-Time PCR (qPCR) to detect and quantify lichenicolous fungi and lichen bionts. We investigated the lichenicolous fungi Plectocarpon lichenum and Tremella Lobariacearum which inhabit species of the genus Lobaria using the following sample types to determine intrathalline distribution patterns: material with obvious infections, material next to infections, as well as visually uninfected plectenchyma from central and marginal thallus parts. Furthermore, some visually uninfected thalli were sampled for ...
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characterization of microsatellite loci in the himalayan lichen fungus Lobaria pindarensis Lobariaceae
Applications in Plant Sciences, 2014Co-Authors: Shiva Devkota, Carolina Cornejo, Silke Werth, Ram Prasad Chaudhary, Christoph ScheideggerAbstract:Premise of the study: Microsatellite loci were developed for the rare, Himalayan, endemic haploid lichen fungus, Lobaria pindarensis, to study its population subdivision and the species' response to forest disturbance and fragmentation. Methods and Results: We developed 18 polymorphic microsatellite markers using 454 pyrosequencing data and assessed them in 109 individuals. The number of alleles per locus ranged from three to 11 with an average of 6.9. Nei's unbiased gene diversity, averaged over loci, ranged from 0.514 to 0.685 in the three populations studied. The cross-amplification success with related species (L. chinensis, L. gyrophorica, L. isidiophora, L. orientalis, L. pulmonaria, L. spathulata, and Lobaria sp.) was generally high and decreased with decreasing relationship to L. pindarensis. Conclusions: The new markers will allow the study of genetic diversity and differentiation within L. pindarensis across its distribution. Moreover, they will enable us to study the effects of forest managemen...
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Characterization of microsatellite loci in the lichen fungus Lobaria pulmonaria (Lobariaceae)
Applications in Plant Sciences, 2013Co-Authors: Silke Werth, Carolina Cornejo, Christoph ScheideggerAbstract:Premise of the study: Microsatellite loci were developed for the threatened haploid lichen fungus Lobaria pulmonaria to increase the resolution to identify clonal individuals, and to study its population subdivision. Methods and Results: We developed 14 microsatellite markers from 454 DNA sequencing data of L. pulmonaria and tested for cross-amplification with L. immixta and L. macaronesica. The number of alleles per locus ranged from two to 23. Nei's unbiased gene diversity, averaged over loci, ranged from 0.434 to 0.517 in the three studied populations. Conclusions: The new markers will increase the genetic resolution in studies that aim at disentangling clones in L. pulmonaria and may be useful for closely related species within Lobaria sect. Lobaria.
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a species specific real time pcr assay for identification of three lichen forming fungi Lobaria pulmonaria Lobaria immixta and Lobaria macaronesica
Molecular Ecology Resources, 2010Co-Authors: Silke Werth, Carolina Cornejo, Christoph ScheideggerAbstract:We present a multiplex real-time PCR assay for the simultaneous identification of three morphologically similar species of lichen-forming fungi, Lobaria pulmonaria, Lobaria immixta and Lobaria macaronesica. Based on TaqMan MGB (minor groove binding) probes targeting the fungal internal transcribed spacer (ITS nrDNA) region, our assay unambiguously identifies known samples from all the three species, thus providing a powerful alternative to the more expensive DNA-sequencing techniques.
Carolina Cornejo - One of the best experts on this subject based on the ideXlab platform.
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multi gene phylogeny of the genus Lobaria evidence of species pair and allopatric cryptic speciation in east asia
American Journal of Botany, 2015Co-Authors: Carolina Cornejo, Christoph ScheideggerAbstract:PREMISE OF THE STUDY Accurate species delimitation has critical implications for ecological and conservation studies. The lichen genus Lobaria is widely distributed in old-growth forests. Particularly in East Asia, this genus includes many rare and poorly known taxa that are circumscribed as morpho- or chemospecies, as well as species-pairs. METHODS To critically examine the relationships between species identified via morphological and chemical criteria, phylogenetic species recognition (PSR) was applied to the genus Lobaria. Morphological and chemical patterns of 87 individuals were examined and three independent nuclear loci were sequenced. The East Asian L. meridionalis-group was additionally studied using split decomposition and haplotype network analysis. KEY RESULTS The genus Lobaria and most of its species were strongly supported statistically. Split decomposition and haplotype networks suggest complex evolutionary histories of species within the East Asian L. meridionalis-group. CONCLUSIONS Phylogenetic analyses confirmed the monophyly of the genus Lobaria, including L. anomala. Within Lobaria, three major clades were found. These clades associate with different photobionts and comprise 18 known species and 5 undescribed species. Several chemical compounds were found to be neither stable nor invariant characters. Some taxa of the L. meridionalis-group appear to be monophyletic but remain as allopatric cryptic species. In three clades, this study found evidence for diversification processes between isidiate and nonisidiate specimens (species-pair). These findings are discussed in the context of evolutionary hypotheses for speciation processes.
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characterization of microsatellite loci in the himalayan lichen fungus Lobaria pindarensis Lobariaceae
Applications in Plant Sciences, 2014Co-Authors: Shiva Devkota, Carolina Cornejo, Silke Werth, Ram Prasad Chaudhary, Christoph ScheideggerAbstract:Premise of the study: Microsatellite loci were developed for the rare, Himalayan, endemic haploid lichen fungus, Lobaria pindarensis, to study its population subdivision and the species' response to forest disturbance and fragmentation. Methods and Results: We developed 18 polymorphic microsatellite markers using 454 pyrosequencing data and assessed them in 109 individuals. The number of alleles per locus ranged from three to 11 with an average of 6.9. Nei's unbiased gene diversity, averaged over loci, ranged from 0.514 to 0.685 in the three populations studied. The cross-amplification success with related species (L. chinensis, L. gyrophorica, L. isidiophora, L. orientalis, L. pulmonaria, L. spathulata, and Lobaria sp.) was generally high and decreased with decreasing relationship to L. pindarensis. Conclusions: The new markers will allow the study of genetic diversity and differentiation within L. pindarensis across its distribution. Moreover, they will enable us to study the effects of forest managemen...
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Characterization of microsatellite loci in the lichen fungus Lobaria pulmonaria (Lobariaceae)
Applications in Plant Sciences, 2013Co-Authors: Silke Werth, Carolina Cornejo, Christoph ScheideggerAbstract:Premise of the study: Microsatellite loci were developed for the threatened haploid lichen fungus Lobaria pulmonaria to increase the resolution to identify clonal individuals, and to study its population subdivision. Methods and Results: We developed 14 microsatellite markers from 454 DNA sequencing data of L. pulmonaria and tested for cross-amplification with L. immixta and L. macaronesica. The number of alleles per locus ranged from two to 23. Nei's unbiased gene diversity, averaged over loci, ranged from 0.434 to 0.517 in the three studied populations. Conclusions: The new markers will increase the genetic resolution in studies that aim at disentangling clones in L. pulmonaria and may be useful for closely related species within Lobaria sect. Lobaria.
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new morphological aspects of cephalodium formation in the lichen Lobaria pulmonaria lecanorales ascomycota
Lichenologist, 2013Co-Authors: Carolina Cornejo, Christoph ScheideggerAbstract:Cephalodia were investigated on young and mature thalli of Lobaria pulmonaria. Cephalodia originate from contact between hyphae and cyanobacteria on the upper or lower cortex or, less frequently, in the apical zone. Young thalli were found to associate with cyanobacteria even in the anchoring zone. Cephalodia formed on the young thalli or the anchoring hyphae share the same phenotypic characteristics. In spite of being composed of paraplectenchymatous hyphae, the cortex of mature thalli preserves a considerable plasticity, enabling the formation of cephalodia. The cyano- bacterial incorporation process begins with cortical hyphae growing out towards adjacent cyanobac- terial colonies, enveloping them and incorporating them into the thallus. The incorporation process is the same on the upper and the lower cortex. Early stages of cephalodia are usually found in young lobes, whereas in the older parts of the thallus only mature cephalodia are found.
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Lobaria macaronesica sp nov and the phylogeny of Lobaria sect Lobaria Lobariaceae in macaronesia
The Bryologist, 2010Co-Authors: Carolina Cornejo, Christoph ScheideggerAbstract:The species in Lobaria sect. Lobaria are circumscribed based on secondary metabolites and the morphology of vegetative propagules such as isidia and soredia. Lobaria pulmonaria typically forms soredia, which distinguish it from the other species of this section. However, in L. pulmonaria soredia may develop into isidioid soredia that can be confused with isidia. In Macaronesia, this difficulty gave rise to controversial discussion about the taxonomic status of L. pulmonaria var. meridionalis, which forms cylindrical diaspores. In the present study, a three loci approach (ITS, RPB2 and EF-1α) was used to investigate the taxonomic status of L. pulmonaria var. meridionalis based on a phylogeny of Macaronesian taxa of the L. pulmonaria group. Phylogenetic analyses reveal that L. pulmonaria v. meridionalis is a distinct taxon, which is here proposed at the rank of species: Lobaria macaronesica Cornejo & Scheidegger sp. nov. The new species is genetically distinct from the Asian L. meridionalis, the cosmopolitan L. pulmonaria and the Macaronesian L. immixta.
Marcello Iacomini - One of the best experts on this subject based on the ideXlab platform.
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rhamnogalactofuranan from the microalga myrmecia biatorellae symbiotic partner of Lobaria linita
Phytochemistry, 2013Co-Authors: Lucimara M C Cordeiro, Flavio Beilke, Vanessa De Fatima Reinhardt, Guilherme L Sassaki, Marcello IacominiAbstract:A structural study of the cell wall polysaccharides of Myrmecia biatorellae, the symbiotic algal partner of the lichenized fungus Lobaria linita was carried out. It produced a cold-water insoluble rhamnogalactofuranan, with a (1 ? 3)-linked b-D-galactofuranosyl main-chain, substituted at O-6 by single units of b-DGalf, or by side-chains of 2-O- and 2,4-di-O-linked a-L-Rhap units. The structure of the polysaccharide was established by chemical and NMR spectroscopic analysis.
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1 2 and 1 6 linked β d galactofuranan of microalga myrmecia biatorellae symbiotic partner of Lobaria linita
Carbohydrate Polymers, 2012Co-Authors: Lucimara M C Cordeiro, Flavio Beilke, Vanessa De Fatima Reinhardt, Franciele Lima Bettim, Yanna D Rattmann, Marcello IacominiAbstract:A structural study of the cell wall polysaccharides of Myrmecia biatorellae, the symbiotic algal partner of the lichenized fungus Lobaria linita was carried out. It produced a rhamnogalactofuranan, with a (1→6)-β-D-galactofuranose in the main-chain, substituted at O-2 by single units of β-D-Galf, α-L-Rhap or by side chains of 2-O-linked β-D-Galf units. The structure of the polysaccharide was established by chemical and NMR spectroscopic analysis, and is new among natural polysaccharides. Moreover, in a preliminary study, this polysaccharide increased the lethality of mice submitted to polymicrobial sepsis induced by cecal ligation and puncture, probably due to the presence of galactofuranose, which have been shown to be highy immunogenic in mammals.