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1.
Chemosphere ; 184: 700-710, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28633065

RESUMO

A 2014 case study investigated the relative accumulation efficiency of polycyclic aromatic hydrocarbons (PAHs), total sulfur (S), total nitrogen (N), major and minor elements and Pb isotopes in five common lichen species at three boreal forest sites in the Athabasca Oil Sands Region (AOSR) in northeastern Alberta, Canada to identify the optimum lichen species for future biomonitoring. Differences in concentrations of PAHs, multiple elements, and Pb isotopes in fruticose (Bryoria furcellata, Cladina mitis, Evernia mesomorpha) and foliose (Hypogymnia physodes and Tuckermannopsis americana) lichens were found along a 100 km distance gradient from the primary oil sands operations. Integration of insights from emission source samples and oil sands mineralogy in consort with aerosol collection indicates incorporation of more fine particulate matter (PM) into foliose than fruticose lichen biomass. Contrasting PAH with element concentrations allowed lichen species specific accumulation patterns to be identified. The ability of lichen species to incorporate different amounts of gas phase (S and N), petrogenic (V, Ni, Mo), clay (low Si/Al and more rare earth elements), and sand (higher Si/Al and Ti) components from the oil sand operations reflects aerosol particle size and lichen physiology differences that translate into differences in PM transport distances and lichen accumulation efficiencies. Based on these findings Hypogymnia physodes is recommended for future PAH biomonitoring and source attribution studies.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/análise , Chumbo/análise , Líquens/classificação , Metais Terras Raras/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Alberta , Isótopos , Nitrogênio , Campos de Petróleo e Gás , Tamanho da Partícula , Material Particulado
2.
J Eukaryot Microbiol ; 62(2): 196-205, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25105247

RESUMO

The composition of lichen ecosystems except mycobiont and photobiont has not been evaluated intensively. In addition, recent studies to identify algal genotypes have raised questions about the specific relationship between mycobiont and photobiont. In the current study, we analyzed algal and fungal community structures in lichen species from King George Island, Antarctica, by pyrosequencing of eukaryotic large subunit (LSU) and algal internal transcribed spacer (ITS) domains of the nuclear rRNA gene. The sequencing results of LSU and ITS regions indicated that each lichen thallus contained diverse algal species. The major algal operational taxonomic unit (OTU) defined at a 99% similarity cutoff of LSU sequences accounted for 78.7-100% of the total algal community in each sample. In several cases, the major OTUs defined by LSU sequences were represented by two closely related OTUs defined by 98% sequence similarity of ITS domain. The results of LSU sequences indicated that lichen-associated fungi belonged to the Arthoniomycetes, Eurotiomycetes, Lecanoromycetes, Leotiomycetes, and Sordariomycetes of the Ascomycota, and Tremellomycetes and Cystobasidiomycetes of the Basidiomycota. The composition of major photobiont species and lichen-associated fungal community were mostly related to the mycobiont species. The contribution of growth forms or substrates on composition of photobiont and lichen-associated fungi was not evident.


Assuntos
Fungos/classificação , Líquens/classificação , Regiões Antárticas , Biodiversidade , Clorófitas/classificação , Ecossistema , Genes de RNAr , Genótipo , Líquens/genética , Filogenia , Análise de Sequência de DNA
3.
Int J Med Mushrooms ; 16(1): 17-28, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24940901

RESUMO

Telomerase has been widely accepted as a cancer marker and a promising therapeutic target for novel anticancer drugs. The aim of this study was to investigate the in vitro telomerase inhibitory effects of mushrooms and their anticancer properties. The inhibitory effects of mushrooms and lichens against telomerase activity of HL-60 cells were systematically assessed using polymerase chain reaction based on assay of telomeric repeat amplification protocol. Telomerase inhibitory samples were further tested for antiproliferation effects against the gastric cell line SNU-1 using the MTT method. Ethyl acetate extract of Pleurotus ostreatus, ethyl acetate and water extracts of Lasiosphaera fenzlii, hexane extract of Strobilomyces floccopus, water extract of Sarcodon aspratus, and hexane, ethyl acetate, and water extracts from Umbilicaria esculenta showed strong positive telomerase inhibitory activity. Hexane extract of S. floccopus and water extracts from the edible lichen U. esculenta exhibited strong anticancer effects against SNU-1 cells through antiproliferation assay. The water extract of U. esculenta has a great potential to be developed into an anticancer agent that targets telomerase.


Assuntos
Agaricales/química , Antineoplásicos Fitogênicos/farmacologia , Líquens/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Telomerase/antagonistas & inibidores , Agaricales/classificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Líquens/classificação , Telomerase/metabolismo , Verduras/química
4.
Drug Discov Ther ; 8(2): 84-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24815583

RESUMO

Three new anthraquinone derivatives (1-3) and one new artifact (4) were isolated, along with six known anthraquinone derivatives (5-10) and three xanthones (11-13), from a culture of an endolichenic fungus, Aspergillus versicolor, that was isolated from the lichen Lobaria retigera. The structures of these substances were determined on the basis of 1D and 2D (COSY, HMQC, and HMBC) NMR and MS analyses. The substances 1-4 were also tested for their cytotoxic activity.


Assuntos
Antraquinonas/metabolismo , Aspergillus/metabolismo , Líquens/microbiologia , Xantonas/metabolismo , Antraquinonas/química , Antraquinonas/isolamento & purificação , Antraquinonas/farmacologia , Aspergillus/classificação , Aspergillus/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Líquens/classificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray , Xantonas/química , Xantonas/isolamento & purificação , Xantonas/farmacologia
5.
ISME J ; 8(10): 2104-15, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24694713

RESUMO

Biological soil crusts (BSC) are the dominant functional vegetation unit in some of the harshest habitats in the world. We assessed BSC response to stress through changes in biotic composition, CO2 gas exchange and carbon allocation in three lichen-dominated BSC from habitats with different stress levels, two more extreme sites in Antarctica and one moderate site in Germany. Maximal net photosynthesis (NP) was identical, whereas the water content to achieve maximal NP was substantially lower in the Antarctic sites, this apparently being achieved by changes in biomass allocation. Optimal NP temperatures reflected local climate. The Antarctic BSC allocated fixed carbon (tracked using (14)CO2) mostly to the alcohol soluble pool (low-molecular weight sugars, sugar alcohols), which has an important role in desiccation and freezing resistance and antioxidant protection. In contrast, BSC at the moderate site showed greater carbon allocation into the polysaccharide pool, indicating a tendency towards growth. The results indicate that the BSC of the more stressed Antarctic sites emphasise survival rather than growth. Changes in BSC are adaptive and at multiple levels and we identify benefits and risks attached to changing life traits, as well as describing the ecophysiological mechanisms that underlie them.


Assuntos
Dióxido de Carbono/metabolismo , Carbono/metabolismo , Ecossistema , Líquens/metabolismo , Microbiologia do Solo , Biomassa , Clima , Gases/metabolismo , Líquens/classificação , Fotossíntese , Solo , Temperatura
6.
Mycologia ; 105(4): 994-1018, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23709574

RESUMO

A combination of molecular phylogenetic analyses of ITS and mtSSU sequences, morphological and chemical analyses were used to investigate the lineages nominally included in the sterile lichen genus Lepraria. A core group (Lepraria s. str.) was resolved as sister to Stereocaulon. Species producing the secondary compounds argopsin, pannarin and usnic acid were found to belong to other lineages of lichen-forming ascomycetes. Study of Leprocaulon revealed that all species, except the type, likely represent members of Lepraria s. str. that have evolved a fruticose growth form. The correct name for the type species of Leprocaulon is shown to be L. quisquiliare, not L. microscopicum, and the genus is redefined to include several species previously placed in Lepraria. Leprocaulon quisquiliare is also shown to comprise two morphologically convergent species. The name is lectotypified and epitypified on material from the type region (Germany) and its application restricted to Old World populations. New World populations of L. quisquiliare are described as L. americanum. Leprocaulon, in its revised sense, is recognized in a new family (Leprocaulaceae) and order (Leprocaulales) sister to the Caliciales and including the genus Halecania. A new genus of Pilocarpaceae, Nelsenium, is introduced to accommodate Lepraria usnica. The status of Lepraria ecorticata is discussed in the context of usnic acid-producing Lecanora species. These nomenclatural novelties are proposed: (i) transfers from Leprocaulon to Lepraria: Lepraria albicans comb. nov., L. arbuscula comb. nov., L. congestum comb. nov., L. gracilescens comb. nov., L. pseudoarbuscula comb. nov., L. subalbicans comb. nov., L. tenellum comb. nov.; (ii) transfers from Lepraria to Leprocaulon: Leprocaulon adhaerens comb. nov., L. coriense, L. santamonicae comb. nov., L. terricola comb. nov. and L. textum comb. nov.; (iii) new taxa: Leprocaulales ord. nov., Leprocaulaceae fam. nov., Nelsenium gen. nov., Leprocaulon americanum sp. nov. and L. knudsenii sp. nov.


Assuntos
Líquens/classificação , Evolução Biológica , Líquens/citologia , Líquens/genética , Líquens/crescimento & desenvolvimento , Filogenia
7.
Rev. biol. trop ; 60(2): 843-856, June 2012. graf, tab
Artigo em Espanhol | LILACS | ID: lil-657823

RESUMO

Phorophyte specificity and microenvironmental preferences of corticolous lichens in five phorophyte species from premontane forest of Finca Zíngara, Cali, Colombia). Lichenized fungi or lichens are organisms that have been little studied in the tropics and which distribution is affected by microenvironmental factors and substrate characteristics. The present study aimed to identify phorophyte specificity and microenvironmental preferences of corticolous lichens in five phorophyte species from premontane forest of the farm Finca Zingara in Cali, Colombia. For this, five individuals were selected from five tree species (phorophytes). Lichen species present in a 0.50x0.20m² quadrant located in the trunk of each tree at a height of 1.3m were identified. Substrate parameters such as bark pH, Diameter Breast Height (DBH) and bark structure were measured. Also, microenvironmental factors including temperature, humidity and irradiance were determined. In order to detect phorophyte preferences, a non-metric multidimensional scaling (NMS) and indicator species analysis were made. Spearman correlation analysis was used to assert the relationship between environmental variables and groupings found in the NMS. A total of 69 species of lichens were found, of which 37 were identified to species, 18 to genera and 14 were not determined because they were sterile or had no spores. NMS showed that some individuals of the same tree species were grouped alongside the analysis dimensions, and they were related with the factors of light intensity, temperature and DBH. Only three lichens with preference for certain tree species were found (Arthonia microsperma by Meriania sp., Cladonia ceratophylla and sorediado 8 by Clusia sp.), suggesting absence of phorophyte preferences. Thus, it can be concluded that lichens from the study area do not show phorophyte preference, but their distribution is affected by light, temperature and DBH. Rev. Biol. Trop. 60 (2): 843-856. Epub 2012 June 01.


El objetivo de este trabajo fue evaluar la especificidad de forófito y las preferencias microambientales de los líquenes cortícolas en el Bosque de la Finca Zíngara (Cali, Colombia). Asimismo, se seleccionaron cinco individuos de cinco especies de árboles. Además, se identificaron las especies de líquenes presentes en un cuadrante de 0.50x0.20m2 ubicado en el tronco de cada árbol a 1.3 m de altura. También, se midieron parámetros microambientales como pH de la corteza, diámetro a la altura del pecho (DAP), estructura de la corteza, humedad relativa e irradianza. Para detectar las preferencias de forófito, se realizó un escalamiento no métrico multidimensional (NMS) y un análisis de especies indicadoras. Luego se efectúo un análisis de correlación de Spearman para evaluar la relación entre las variables ambientales y los agrupamientos encontrados en el NMS. Se encontraron 69 especies de líquenes, de los cuales 37 fueron determinados hasta especie, 18 hasta género y 14 no fueron determinados. El resultado del NMS mostró que algunos individuos de la misma especie de árbol se agruparon a lo largo de las dimensiones del análisis, y están relacionados con los factores intensidad de luz, temperatura y DAP. Sólo tres especies mostraron preferencia por ciertas especies de árboles (Arthonia microsperma por Meriania sp., Cladonia ceratophylla y sorediado 8 por Clusia sp.), lo cual sugiere ausencia de preferencias de forófito.


Assuntos
Ecossistema , Líquens/fisiologia , Árvores , Colômbia , Líquens/classificação
8.
Biol Res ; 45(4): 387-91, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23558996

RESUMO

A total of twenty four lichen species belonging to six families were collected from mountainous region of Nepal. The methanol extracts of each species were tested for antimicrobial and antioxidant activities in vitro. It was found that extracts of twenty one lichen species were active against B. subtilis and seven species were active against S. aureus. Similarly, in DPPH assay, three species Peltigera sp.,Cladonia sp., and Canoparmelia sp. showed comparable activity with commercial standard, BHA. In ABTS+ assay, extracts of Parmoterma sp., Ramalina sp., Peltigera sp. and Cladonia sp. showed stronger activity than ascorbic acid. The observed data after comparison with previously published reports indicated that the high altitude lichens contain stronger antioxidant and antibacterial constituents. Similarly, the methanol extracts of Heterodermia sp. and Ramalina sp. showed comparable toxicity effect with commercial standard berberine chloride indicating a potent source of anticancer drugs.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Candida albicans/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Líquens/química , Animais , Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Artemia/efeitos dos fármacos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Líquens/classificação , Nepal , Testes de Toxicidade/métodos
9.
Biol. Res ; 45(4): 387-391, 2012. ilus
Artigo em Inglês | LILACS | ID: lil-668691

RESUMO

A total of twenty four lichen species belonging to six families were collected from mountainous region of Nepal. The methanol extracts of each species were tested for antimicrobial and antioxidant activitiesin vitro. It was found that extracts of twenty one lichen species were active againstB. subtilis and seven species were active againstS. aureus. Similarly, in DPPH assay, three speciesPeltigera sp.,Cladonia sp., andCanoparmelia sp. showed comparable activity with commercial standard, BHA. In ABTS+ assay, extracts ofParmoterma sp.,Ramalina sp.,Peltigera sp. andCladonia sp. showed stronger activity than ascorbic acid. The observed data after comparison with previously published reports indicated that the high altitude lichens contain stronger antioxidant and antibacterial constituents. Similarly, the methanol extracts ofHeterodermia sp. andRamalina sp. showed comparable toxicity effect with commercial standard berberine chloride indicating a potent source of anticancer drugs.


Assuntos
Animais , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Candida albicans/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Líquens/química , Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Artemia/efeitos dos fármacos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Líquens/classificação , Nepal , Testes de Toxicidade/métodos
10.
Mol Phylogenet Evol ; 60(3): 317-32, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21627994

RESUMO

Mounting evidence suggests many morphology-based species circumscriptions in lichenized ascomycetes misrepresent fungal diversity. The lichenized ascomycete genus Xanthoparmelia includes over 800 described species displaying a considerable range of morphological and chemical variation. Species circumscriptions in this genus have traditionally been based on thallus morphology, medullary chemistry, and the presence or absence of sexual or asexual reproductive structures. Notwithstanding concerted effort on the part of taxonomists to arrive at a natural classification, modern taxonomic concepts for the most part remain unclear. Here we assess the evolution of characters traditionally regarded as taxonomically important by reconstructing a phylogenetic hypothesis based on sequence data from four nuclear ribosomal markers as well as fragments from two protein-coding nuclear loci. A total of 414 individuals were tested, representing 19 currently accepted species. Most sampled species, as currently circumscribed, were recovered as polyphyletic, suggesting that major diagnostic characters have evolved in a homoplasious manner. The vagrant growth form, distinct medullary chemistries, and production of vegetative diaspores appear to have evolved independently multiple times. Application of a population assignment test resulted in the recognition of 21 species-level genetic clusters, each of which was supported by a comparison of genetic distances as well as a Bayesian species delimitation method calculating probabilities associated with speciation events. Inferred clusters are largely incongruent with traditionally circumscribed species due to the prevalence of cryptic diversity and, in some cases, high levels of intraspecific morphological and chemical variation. These results call for a major taxonomic revision of Xanthoparmelia species in western North America.


Assuntos
Ascomicetos/classificação , Evolução Molecular , Líquens/classificação , Filogenia , Ascomicetos/genética , Teorema de Bayes , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Líquens/genética , América do Norte , Análise de Sequência de DNA
11.
Mycologia ; 103(4): 755-63, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21471292

RESUMO

The monotypic, lichen-forming genus Ingvariella originally was segregated from Diploschistes and placed within the Thelotremataceae (Ostropales) based on aspects of exciple morphology. However, the I+ hymenium and amyloid ascus wall suggest affinities to families other than the Thelotremataceae. To assess the identity of Ingvariella and to investigate its placement within the Ostropales, we inferred phylogenetic relationships of I. bispora by comparison of mtSSU rDNA and nuLSU rDNA sequences for 59 species encompassing a broad array of ostropalean fungi by means of Bayesian, maximum likelihood and weighted maximum parsimony methods. Here we report that Ingvariella is a member of the Stictidaceae, sister to the mainly saprotrophic genus Cryptodiscus. The inclusion of the first saxicolous lichen-forming fungus within this family expands the broad ecological diversity of the Stictidaceae, where saprotrophic fungi, corticicolous lichen-forming fungi and lichenized and non-lichenized conspecific taxa have been described previously. We also present new insights into the relationships among other families within the Ostropales.


Assuntos
Ascomicetos/classificação , Líquens/classificação , Ascomicetos/citologia , Ascomicetos/genética , DNA Fúngico/genética , DNA Ribossômico/genética , Líquens/citologia , Líquens/genética , Filogenia , Análise de Sequência de DNA
12.
Biol. Res ; 43(2): 169-176, 2010. ilus
Artigo em Inglês | LILACS | ID: lil-567531

RESUMO

The aim of this study was to investigate metabolites of the lichen Laurera benguelensis. A high-performance liquid chromatographic (HPLC) method has been developed for the characterization of xanthones and anthraquinones in extracts of this lichen. Lichexanthone, secalonic acid D, norlichexanthon, parietin, emodin, teloschistin and citreorosein were detected in the lichen samples, which were collected from two places in Thailand. Components of the lichen were identifed by relative retention time and spectral data. This is the frst time that a detailed phytochemical analysis of the lichen L. benguelensis was reported and this paper has chemotaxonomic signifcance because very little has been published on the secondary metabolites present in Laurera species. Some of the metabolites were detected for the frst time in the family Trypetheliaceae. The results of preliminary testing of benzene extract and its chloroform and methanol fractions showed that all samples showed a weak radical scavenging activity. The chloroform extract showed the highest antioxidant activity.


Assuntos
Antraquinonas/análise , Sequestradores de Radicais Livres/análise , Líquens/química , Xantonas/análise , Antraquinonas/química , Cromatografia Líquida de Alta Pressão , Sequestradores de Radicais Livres/química , Líquens/classificação , Tailândia , Xantonas/química
13.
Mycol Res ; 113(Pt 10): 1154-71, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19646529

RESUMO

The Agaricales is the largest and most diverse order of mushroom-forming Basidiomycota, with over 100 natural groups recognized in recent Fungal Tree of Life studies. Most agarics are either saprotrophic or ectomycorrhizal fungi, but the family Hygrophoraceae is in part characterized by a unique and remarkable diversity of lichenized forms. The most familiar of these is the chlorolichen genus Lichenomphalia, whose phylogenetic position in the Agaricales has been established. Recent limited evidence suggested that Hygrophoraceae also contains cyanolichens in the genus Dictyonema, which indicates a remarkable concentration and diversity of lichen-formers in a single family of agarics. To demonstrate the relationships of lichen-formers to other fungi in the family, we assembled ribosomal sequences from 52 species representing recognized groups within the Hygrophoraceae, among them new sequences representing Acantholichen and most species and forms of Dictyonema. The molecular data were evaluated using parsimony, likelihood, Bayesian, and distance analyses, including coding of ambiguous regions by means of INAASE and ARC, all of which indicate that Dictyonema and Acantholichen form a monophyletic clade derived from the primarily bryophilous genus Arrhenia and sister to the enigmatic Athelia pyriformis, a species unrelated to the Atheliales for which we are proposing a new genus name Eonema. The chlorolichen genus Lichenomphalia may be polyphyletic. Fungi in the Dictyonema-Acantholichen clade are typically tropical, entirely lichenized, and associate with cyanobacterial photobionts. Our data indicate a transition from agaricoid-omphalinoid basidiomes observed in Arrhenia to stereoid-corticioid forms in Dictyonema, and also support a previous suggestion of a connection between loss of clamp connections and lichenization. The diverse basidiome and thallus morphologies and nutritional ecologies of these fungi indicate a remarkable evolutionary flexibility that appears to have developed in part as a consequence of symbiosis.


Assuntos
Agaricales/classificação , Líquens/classificação , Filogenia , Agaricales/química , Agaricales/genética , Sequência de Aminoácidos , Basidiomycota/classificação , Basidiomycota/genética , Evolução Molecular , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Líquens/química , Líquens/genética , Dados de Sequência Molecular , Alinhamento de Sequência
14.
Mol Phylogenet Evol ; 53(3): 862-71, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19695332

RESUMO

Many lichen fungi form symbioses with filamentous Nostoc cyanobacteria, which cause the lichen to swell and become extremely gelatinous when moist. Within the Lecanoromycetes, such gelatinous lichens are today mainly classified in the Collemataceae (Peltigerales, Ascomycota). We performed Bayesian MCMC, maximum likelihood, and maximum parsimony analyses of three independent markers (mtSSU rDNA, nuLSU rDNA, and RPB1), to improve our understanding of the phylogeny and classification in the Peltigerales, as well as the evolution of morphological characters that have been used for classification purposes in this group. The Collemataceae and the non-gelatinous Pannariaceae are paraphyletic but can be re-circumscribed as monophyletic if Leciophysma, Physma, Ramalodium and Staurolemma are transferred to the Pannariaceae. The gelatinous taxa transferred to the Pannariaceae deviate from other Collemataceae in having simple ascospores, and several also have a ring-shaped exciple as in other Pannariaceae, rather than the disc-shaped exciple found in the typical Collemataceae. Both Collema and Leptogium are non-monophyletic. The re-circumscribed Collemataceae shares a distinct ascus type with the sister group Placynthiaceae and the Coccocarpiaceae, whereas Pannariaceae includes a variety of structures. All Pannariaceae have one-celled ascospores, whereas all Collemataceae have two- or multi-celled spores. Reconstructions of the number of character state transformations in exciple structure, thallus gelatinosity, and ascus apex structure indicate that the number of transformations is distinctly higher than the minimum possible. Most state transformations in the exciple took place from a ring-shaped to a disc-shaped exciple. Depending on the reconstruction method, most or all transformations in thallus structure took place from a non-gelatinous to a gelatinous thallus. Gains and losses of internal structures in the ascus apex account for all or a vast majority of the number of transformations in the ascus, whereas direct transformations between asci with internal structures appear to have been rare.


Assuntos
Ascomicetos/genética , Evolução Molecular , Líquens/genética , Filogenia , Ascomicetos/classificação , Teorema de Bayes , DNA Fúngico/genética , DNA Mitocondrial/genética , DNA Ribossômico/genética , Líquens/classificação , Funções Verossimilhança , Alinhamento de Sequência , Análise de Sequência de DNA , Esporos Fúngicos/genética
15.
Mycol Res ; 112(Pt 11): 1307-18, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18945603

RESUMO

Phylogenetic relationships of the lichen genus Polyblastia and closely related taxa in the family Verrucariaceae (Verrucariales, Chaetothyriomycetidae) were studied. A total of 130 sets of sequences (nuLSU rDNA, nuITS rDNA and RPB1 region A-D), including 129 newly generated sequences, were analysed. Phylogenetic relationships were inferred using a Bayesian approach based on two datasets. A first analysis of a larger, two-locus dataset (nuLSU and RPB1) for 128 members of the Verrucariaceae, confirmed the polyphyly of Polyblastia, Thelidium, Staurothele, and Verrucaria, as currently construed. The second analysis focused on 56 Polyblastia and allied taxa, but using an additional locus (nuITS rDNA) and two closely related outgroup taxa. The latter analysis revealed strongly supported groups, such as Polyblastia s. str., the Thelidium group (a mixture of Polyblastia, Thelidium, Staurothele and Verrucaria species). The genus Sporodictyon, which is here accepted, also accommodates Sporodictyon terrestre comb. nov. Morphological features traditionally used for characterizing Polyblastia, Thelidium, Staurothele and Verrucaria, such as spore septation and colour, occurrence of hymenial photobiont, involucrellum structure, and substrate preference, were found to be only partially consistent within the strongly supported clades, and thus are not always reliable features for characterizing natural groups.


Assuntos
Ascomicetos/classificação , Líquens/classificação , Filogenia , Ascomicetos/citologia , Ascomicetos/genética , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Líquens/citologia , Líquens/genética , Dados de Sequência Molecular , Esporos Fúngicos/citologia
16.
J Microbiol Biotechnol ; 18(6): 1016-23, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18600041

RESUMO

Lichens are predominant and important components of flora in the terrestrial ecosystem of Antarctica. However, relatively few researches on the phylogenetic position of Antarctic lichen-forming fungi have been accomplished. In this study, partial sequences of nuclear large subunit rDNAs from 50 Antarctic specimens were obtained and the phylogeny was reconstructed. Antarctic lichen species were distributed among 4 orders, including the monophyletic order Agyrales, paraphyletic orders Pertusariales and Teloschistales, and polyphyletic order Lecanorales. Species diversity was highest in the order Lecanorales, followed by Teloschistales and Pertusariales. Based on the phylogeny and sequence similarity analyses, it is proposed that the taxonomy of Stereocaulon alpinum, Physcia caesia, Usnea aurantiacoatra, and Cladonia species should be revised by careful examination of their phenotypic and molecular characteristics. Six species known to be endemic to Antarctica, Catillaria corymbosa, Himantormia lugubris, Leptogium puberulum, Pertusaria pertusa, Rhizoplaca aspidophora, and Umbilicaria antarctica, formed unique lineages, implying independent origins in the Antarctic area.


Assuntos
Biodiversidade , DNA Ribossômico/genética , Fungos/genética , Líquens/genética , Filogenia , Regiões Antárticas , DNA Fúngico/genética , Fungos/classificação , Genes Fúngicos , Líquens/classificação , Reação em Cadeia da Polimerase , Subunidades Ribossômicas Maiores de Eucariotos/genética , Alinhamento de Sequência , Análise de Sequência de DNA
17.
Mycol Res ; 112(Pt 5): 528-46, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18406120

RESUMO

The Teloschistaceae is a widespread family with considerable morphological and ecological heterogeneity across genera and species groups. In order to provide a comprehensive molecular phylogeny for this family, phylogenetic analyses were carried out on sequences from the nuclear ribosomal ITS region obtained from 114 individuals that represent virtually all main lineages of Teloschistaceae. Our study confirmed the polyphyly of Caloplaca, Fulgensia and Xanthoria, and revealed that Teloschistes is probably non-monophyletic. We also confirm here that species traditionally included in Caloplaca subgenus Gasparrinia do not form a monophyletic entity. Caloplaca aurantia, C. carphinea and C. saxicola s. str. groups were recovered as monophyletic. The subgenera Caloplaca and Pyrenodesmia were also polyphyletic. In the subgenus Caloplaca, the traditionally recognized C. cerina group was recovered as monophyletic. Because this study is based solely on ITS, to maximize taxon sampling, the inclusion of phylogenetic signal from ambiguously aligned regions in MP (recoded INAASE and arc characters) resulted in the most highly supported phylogenetic reconstruction, compared with Bayesian inference restricted to alignable sites.


Assuntos
Ascomicetos/classificação , Líquens/classificação , Ascomicetos/genética , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Líquens/genética , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência , Análise de Sequência de DNA
18.
Mycol Res ; 112(Pt 1): 50-6, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18207379

RESUMO

The phylogenetic positions of the always-sterile microfilamentous lichens Cystocoleus ebeneus and Racodium rupestre were studied in a phylogenetic framework using sequence data of 5' nuSSU, nuLSU, and mtSSU rDNA. The analysis reveals that both genera are ascomycetes and belong to Dothideomycetidae: they are not close to lichenized members within the subclass, but rather belong to Capnodiales. The macroscopically scarcely distinguishable C. ebeneus and R. rupestre do not form a monophyletic group. The well-supported clade of R. rupestre is basal to the one in which C. ebeneus is close to Mycosphaerellaceae. This study provides another example of ascomycetes with very different life-styles and ecologies being closely related.


Assuntos
Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Líquens/classificação , Líquens/isolamento & purificação , Micoses/microbiologia , Doenças das Plantas/microbiologia , Ascomicetos/genética , Ascomicetos/fisiologia , Áustria , DNA Fúngico/genética , DNA Mitocondrial/genética , DNA Ribossômico , Humanos , Itália , Líquens/genética , Líquens/fisiologia , Dados de Sequência Molecular , Filogenia , Plantas , RNA Ribossômico/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Reino Unido
19.
Mycol Res ; 111(Pt 9): 1064-74, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18029164

RESUMO

An overview of current phylogenetic studies employing molecular data to test previously formulated hypotheses of relationships of loculoascomycetes and pyrenomycetes is given, concentrating on three topics: (1) circumscription and classification of loculoascomycetes, (2) a new classification of Sordariales, and (3) the phylogenetic occurrence of lichenized pyrenomycetes. With regard to these three examples, our review indicates: (1) In traditional taxonomy ascomycetes were classified according to their ascoma-types, with the class Pyrenomycetes including all taxa having perithecia. Later, the development of ascomata and the type of ascus were employed for higher-level classification, and consequently, Loculoascomycetes was separated from Pyrenomycetes. However, molecular studies show that even these revised classifications were too coarse. The Loculoascomycetes fall into two distinct and not closely related groups, which are placed in two clades: Chaetothyriomycetidae and Dothideomycetes. (2) Ascospore morphology has been widely used in taxonomy of ascomycetes, and Sordariales is a prominent example of this. Molecular data suggest that ascomatal wall morphology is a better predictor of phylogenetic relationships in these fungi. Further, the molecular data helped to redefine the circumscription of Sordariales. (3) The majority of non-lichenized pyrenomycetes form a monophyletic group: Sordariomycetes. However, the lichenized pyrenomycetes are highly polyphyletic. Pyrenocarpous lichen-forming fungi occur in several lineages each in Dothideomycetes, Chaetothyriomycetidae, and Lecanoromycetes, whereas no lichenized forms are currently known in the classical pyrenomycetous Sordariomycetes.


Assuntos
Ascomicetos/classificação , Ascomicetos/genética , Filogenia , Ascomicetos/citologia , Líquens/classificação , Líquens/citologia , Líquens/genética , Sordariales/classificação , Sordariales/citologia , Sordariales/genética
20.
Mycol Res ; 111(Pt 9): 999-1000, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17981021

RESUMO

Molecular phylogenetic studies have made it evident that similar fruit body types, formerly the cornerstone of the classification of ascomycete and basidiomycete fungi, including those that form lichens, are often a result of convergent evolution. This commentary provides an introduction to this special issue of Mycological Research, which is based on papers presented at a one-day joint meeting of the British Mycological Society and the Natural History Museum held in London on 3 December 2005. The nine papers included address this issue in relation to its impact on classification, and also draw attention to the over-emphasis in fungal classification of ascus types and, in the case of lichen fungi, thallus form.


Assuntos
Ascomicetos/classificação , Ascomicetos/citologia , Basidiomycota/classificação , Basidiomycota/citologia , Carpóforos/citologia , Filogenia , Líquens/classificação , Líquens/citologia
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