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101.
Valéria Martins Godinho Maria Theresa Rafaela de Paula Débora Amorim Saraiva Silva Karla Paresque Aline Paternostro Martins Pio Colepicolo Carlos Augusto Rosa Luiz Henrique Rosa 《Fungal biology》2019,123(7):507-516
In the present study, we surveyed the distribution and diversity of fungal assemblages associated with 10 species of marine animals from Antarctica. The collections yielded 83 taxa from 27 distinct genera, which were identified using molecular biology methods. The most abundant taxa were Cladosporium sp. 1, Debaryomyces hansenii, Glaciozyma martinii, Metschnikowia australis, Pseudogymnoascus destructans, Thelebolus cf. globosus, Pseudogymnoascus pannorum, Tolypocladium tundrense, Metschnikowia australis, and different Penicillium species. The diversity, richness, and dominance of fungal assemblages ranged among the host; however, in general, the fungal community, which was composed of endemic and cold-adapted cosmopolitan taxa distributed across the different sites of Antarctic Peninsula, displayed high diversity, richness, and dominance indices. Our results contribute to knowledge about fungal diversity in the marine environment across the Antarctic Peninsula and their phylogenetic relationships with species that occur in other cold, temperate, and tropical regions of the World. Additionally, despite their extreme habitats, marine Antarctic animals shelter cryptic and complex fungal assemblages represented by endemic and cosmopolitan cold-adapted taxa, which may represent interesting models to study different symbiotic associations between fungi and their animal hosts in the extreme conditions of Antarctica. 相似文献
102.
Symplocos saxatilis (Symplocaceae), a new dioecious species from Serra do Cipó, Minas Gerais, Brazil
João Luiz M. Aranha Filho Peter W. Fritsch Frank Almeda Angela B. Martins 《Brittonia》2007,59(3):233-237
Symplocos saxatilis from Serra do Cipó, Minas Gerais State, Brazil, is newly described and illustrated on the basis of field and herbarium studies.
It appears to be restricted to “campo rupestre” (rocky field) habitats. This new species is characterized by its 1- to 3-flowered
pedunculate inflorescence, 11 to 14 staminodes of the pistillate flowers, and 0.7–1.5 mm thick endocarp. 相似文献
103.
Habitat fragmentation, variable edge effects, and the landscape-divergence hypothesis 总被引:2,自引:0,他引:2
Laurance WF Nascimento HE Laurance SG Andrade A Ewers RM Harms KE Luizão RC Ribeiro JE 《PloS one》2007,2(10):e1017
Edge effects are major drivers of change in many fragmented landscapes, but are often highly variable in space and time. Here we assess variability in edge effects altering Amazon forest dynamics, plant community composition, invading species, and carbon storage, in the world's largest and longest-running experimental study of habitat fragmentation. Despite detailed knowledge of local landscape conditions, spatial variability in edge effects was only partially foreseeable: relatively predictable effects were caused by the differing proximity of plots to forest edge and varying matrix vegetation, but windstorms generated much random variability. Temporal variability in edge phenomena was also only partially predictable: forest dynamics varied somewhat with fragment age, but also fluctuated markedly over time, evidently because of sporadic droughts and windstorms. Given the acute sensitivity of habitat fragments to local landscape and weather dynamics, we predict that fragments within the same landscape will tend to converge in species composition, whereas those in different landscapes will diverge in composition. This 'landscape-divergence hypothesis', if generally valid, will have key implications for biodiversity-conservation strategies and for understanding the dynamics of fragmented ecosystems. 相似文献
104.
Leite ES Santana SR Hünenberger PH Freitas LC Longo RL 《Journal of molecular modeling》2007,13(9):1017-1025
The relative stabilities of the alkali [M ⊂ 222]+ cryptates (M = Na, K, Rb and Cs) in the gas phase and in solution (80:20 v/v methanol:water mixture) at 298 K, are computed
using a combination of ab initio quantum-chemical calculations (HF/6-31G and MP2/6-31+G*//HF/6-31+G*) and explicit-solvent
Monte Carlo free-energy simulations. The results suggest that the relative stabilities of the cryptates in solution are due
to a combination of steric effects (compression of large ions within the cryptand cavity), electronic effects (delocalization
of the ionic charge onto the cryptand atoms) and solvent effects (dominantly the ionic dessolvation penalty). Thus, the relative
stabilities in solution cannot be rationalized solely on the basis of a simple match or mismatch between the ionic radius
and the cryptand cavity size as has been suggested previously. For example, although the [K ⊂ 222]+ cryptate is found to be the most stable in solution, in agreement with experimental data, it is the [Na ⊂ 222]+ cryptate that is the most stable in the gas phase. The present results provide further support to the notion that the solvent
in which supramolecules are dissolved plays a key role in modulating molecular recognition processes.
Figure Alkali cryptates [M ⊂ 222]+ (M = Na, K, Rb and Cs) relative stabilities in gas and methanol:water solution: solvent effects
and molecular recognition
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
105.
Pereira LA Báo SN Barbosa MS da Silva JL Felipe MS de Santana JM Mendes-Giannini MJ de Almeida Soares CM 《FEMS yeast research》2007,7(8):1381-1388
Paracoccidioides brasiliensis is an important fungal pathogen. The disease it causes, paracoccidioidomycosis (PCM), ranges from localized pulmonary infection to systemic processes that endanger the life of the patient. Paracoccidioides brasiliensis adhesion to host tissues contributes to its virulence, but we know relatively little about molecules and the molecular mechanisms governing fungal adhesion to mammalian cells. Triosephosphate isomerase (TPI: EC 5.3.1.1) of P. brasiliensis (PbTPI) is a fungal antigen characterized by microsequencing of peptides. The protein, which is predominantly expressed in the yeast parasitic phase, localizes at the cell wall and in the cytoplasmic compartment. TPI and the respective polyclonal antibody produced against this protein inhibited the interaction of P. brasiliensis to in vitro cultured epithelial cells. TPI binds preferentially to laminin, as determined by peptide inhibition assays. Collectively, these results suggest that TPI is required for interactions between P. brasiliensis and extracellular matrix molecules such as laminin and that this interaction may play an important role in the fungal adherence and invasion of host cells. 相似文献
106.
Karoline Ceron Luiz Gustavo R. Oliveira‐Santos Camila S. Souza Daniel O. Mesquita Francis L. S. Caldas Andra C. Araujo Diego J. Santana 《Oikos》2019,128(11):1537-1548
Life on Earth is supported by an infinite number of interactions among organisms. Species interactions in these networks are influenced by latitude, evolutionary history and species traits. We performed a global‐scale literature analysis to build up a database of interactions between anuran communities and their preys, from a wide range of geographical areas, using a network approach. For this purpose, we compiled a total of 55 weighted anuran–prey interaction networks, 39 located in the tropics and 16 in temperate areas. We tested the influence of latitude, as well as anuran taxonomic, functional and phylogenetic richness on network metrics. We found that anuran–prey networks are not nested, exhibit low complementary specialization and modularity and high connectance when compared to other types of networks. The main effects on network metrics were related to latitude, followed by anuran taxonomic, functional and phylogenetic richness, a pattern similar to the emerging in mutualistic networks. Our study is the first integrated analysis of the structural patterns in anuran–prey antagonistic interaction networks in different parts of the world. We suggest that different processes, mediated mainly by latitude, are modeling the architecture of anuran–prey networks across the globe. 相似文献
107.
Nathlia Vieira Hissa Safar Luiz Fernando Silva Magnago Samir Gonalves Rolim Carlos Ernesto Gonalves Reynauld Schaefer 《Biotropica》2019,51(3):342-354
Human impacts can affect the soil properties through erosion and leaching, the ecosystem functions and, consequently, the capacity of a forest to regenerate. Here, we determine the effects of forest disturbance and succession on selected soil chemical properties using two different approaches, before‐after‐control‐impact (BACI) and space‐for‐time (SFT) substitution, and the threatened Atlantic Forest biome as model. We assessed with BACI the long‐term (37‐year) effects of clear cutting on soil properties by comparing data from two topsoil surveys (1978–2017) divided into two treatments: a preserved old growth forest (control) and an adjacent forest that was experimentally cleared with full tree removal (clear‐cut). We examined with SFT the relationship between stand age and soil properties using soil data from three old growth and 13 s growth forests ranging from 7 to 33 years. We found no significant differences between treatments for any soil property or significant changes in phosphorus, potassium, and calcium + magnesium over time. In contrast, pH increased and aluminum decreased in both areas. No relation was found between forest age and most of soil properties, with the exception of potassium which returned to old growth forest levels after 20 years of natural succession, and pH. BACI indicated that deforestation of old growth forest caused no significant effects on soil chemical properties after 37 years of regeneration. SFT demonstrated that soil properties did not change significantly during forest regeneration on formerly disturbed lands. Our findings indicate that natural nutrient‐depleted lowland forests were overall resistant to deforestation followed by passive regeneration at landscape scale. Abstract in Portuguese is available with online material. 相似文献
108.
Fernando J. J. Muoz‐Lazo Valentina Franco‐Trecu Daniel E. Naya Luiz A. Martinelli Ariovaldo P. Cruz‐Neto 《Biotropica》2019,51(5):709-718
Habitat fragmentation could alter ecological traits including species trophic habits. Here, we used carbon and nitrogen stable isotope ratios to establish differences in isotopic niche width and food resource use between forest fragments and the continuous forest for the phyllostomid frugivorous bat Artibeus lituratus. Using mist nests, we captured bats from two forest fragments and two sites in continuous forest, and sampled from each individual captured three body tissues with contrasting turnover rates (skin, muscle, and liver). Samples were collected between February and March (austral summer) and between August and September (austral winter). In addition, in each sampling site and season we collected potential food resources (fruits and insects) consumed by our A. lituratus. Our findings indicate that A. lituratus had a predominantly omnivorous diet, with high consumption of insects during summer in forest fragments. The increasing consumption of insects in these fragments seems to have led to a wider isotopic niche, in relation to the continuous forest. Because A. lituratus is typically a seed disperser, changes in trophic habits in the forest fragments from frugivory to insectivory may diminish their role in forest regeneration. Abstract in Portuguese is available with online material. 相似文献
109.
Lisiane Hahn Priscilla C. Silva Maria C. Malabarba Luiz R. Malabarba Luís F. Da Câmara Leonardo D. Nunes Leonardo S. Machado Eduardo G. Martins Ronaldo B. Barthem 《Journal of fish biology》2019,95(2):633-637
The genetic analysis of Brachyplatystoma platynemum individuals sampled from the lower Madeira River reinforces the existence of two structured populations in the Amazon Basin (Madeira and Amazon populations). However, the recapture of an individual from the Amazon population in the Solimões River, which was telemetry-tagged in the Madeira River after the damming, indicates that fish from the Amazon population move between the two river systems. This has not yet been observed, however, in the Madeira River population, which is currently divided and isolated in the lower and upper Madeira River by the construction of two dams. 相似文献
110.
Judson Albino Coswosk Elaine Della Giustina Soares Luiz R.R. Faria 《Revista Brasileira de Entomologia》2019,63(1):1-5
Bait traps are effective and commonly used method in the studies of orchid bees. Important questions in the context of this method, including those related to bait dispersion, how long baits remain attractive, the distance from which males are supposed to be attracted to lures and so on, are still open subjects. Data on the attractiveness of bait traps that have remained in the field during two weeks in a large Atlantic forest preserve are presented. Four main results emerge from the data: (i) the abundance of specimens collected per day decreased in all the attractants as the traps were left on the field; (ii) despite this decrease, the absolute number of individuals collected after eight and fifteen days is remarkably, mostly in eugenol and vanillin baits; (iii) the vast majority of species, 22 of 25, was already collected on the first sample day; (iv) a consistent variation in the relative abundance of individuals collected in each scent as collections were made. We urge that bait traps should not be left in the field beyond what is strictly necessary since there is a real possibility of collecting a significant number of individuals as these traps remain available. 相似文献