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We studied the evolutionary history of the Parmeliaceae (Lecanoromycetes, Ascomycota), one of the largest families of lichen-forming fungi with complex and variable morphologies, also including several lichenicolous fungi. We assembled a six-locus data set including nuclear, mitochondrial and low-copy protein-coding genes from 293 operational taxonomic units (OTUs). The lichenicolous lifestyle originated independently three times in lichenized ancestors within Parmeliaceae, and a new generic name is introduced for one of these fungi. In all cases, the independent origins occurred c. 24 million yr ago. Further, we show that the Paleocene, Eocene and Oligocene were key periods when diversification of major lineages within Parmeliaceae occurred, with subsequent radiations occurring primarily during the Oligocene and Miocene. Our phylogenetic hypothesis supports the independent origin of lichenicolous fungi associated with climatic shifts at the Oligocene-Miocene boundary. Moreover, diversification bursts at different times may be crucial factors driving the diversification of Parmeliaceae. Additionally, our study provides novel insight into evolutionary relationships in this large and diverse family of lichen-forming ascomycetes.
Assuntos
Evolução Biológica , Genes Fúngicos , Líquens/genética , Parmeliaceae/genética , Filogenia , Simbiose , ClassificaçãoRESUMO
Inhalation of asbestos fibres can cause lung inflammation and the later development of asbestosis, lung cancer, and mesothelioma, and the use of asbestos is banned in many countries. In most countries, large amounts of asbestos exists within building stock, buried in landfills, and in contaminated soil. Mechanical, thermal, and chemical treatment options do exist, but these are expensive, and they are not effective for contaminated soil, where only small numbers of asbestos fibres may be present in a large volume of soil. Research has been underway for the last 20 years into the potential use of microbial action to remove iron and other metal cations from the surface of asbestos fibres to reduce their toxicity. To access sufficient iron for metabolism, many bacteria and fungi produce organic acids, or iron-chelating siderophores, and in a growing number of experiments these have been found to degrade asbestos fibres in vitro. This paper uses the internal transcribed spacer (ITS) and 16S amplicon sequencing to investigate the fungal and bacterial diversity found on naturally-occurring asbestos minerals, asbestos-containing building materials, and asbestos-contaminated soils with a view to later selectively culturing promising species, screening them for siderophore production, and testing them with asbestos fibres in vitro. After filtering, 895 ITS and 1265 16S amplicon sequencing variants (ASVs) were detected across the 38 samples, corresponding to a range of fungal, bacteria, cyanobacterial, and lichenized fungal species. Samples from Auckland (North Island, New Zealand) asbestos cement, Auckland asbestos-contaminated soils, and raw asbestos rocks from Kahurangi National Park (South Island, New Zealand) were comprised of very different microbial communities. Five of the fungal species detected in this study are known to produce siderophores.
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Amianto , Sideróforos , Nova Zelândia , Ferro/metabolismo , Bactérias/genética , Bactérias/metabolismo , SoloRESUMO
As the 21st century uncovers ever-increasing volumes of asbestos and asbestos-contaminated waste, we need a new way to stop 'grandfather's problem' from becoming that of our future generations. The production of inexpensive, mechanically strong, heat resistant building materials containing asbestos has inevitably led to its use in many public and residential buildings globally. It is therefore not surprising that since the asbestos boom in the 1970s, some 30 years later, the true extent of this hidden danger was exposed. Yet, this severely toxic material continues to be produced and used in some countries, and in others the disposal options for historic uses - generally landfill - are at best unwieldy and at worst insecure. We illustrate the global scale of the asbestos problem via three case studies which describe various removal and/or end disposal issues. These case studies from both industrialised and island nations demonstrate the potential for the generation of massive amounts of asbestos contaminated soil. In each case, the final outcome of the project was influenced by factors such as cost and land availability, both increasing issues, worldwide. The reduction in the generation of asbestos containing materials will not absolve us from the necessity of handling and disposal of contaminated land. Waste treatment which relies on physico-chemical processes is expensive and does not contribute to a circular model economy ideal. Although asbestos is a mineral substance, there are naturally occurring biological-mediated processes capable of degradation (such as bioweathering). Therefore, low energy options, such as bioremediation, for the treatment for asbestos contaminated soils are worth exploring. We outline evidence pointing to the ability of microbe and plant communities to remove from asbestos the iron that contributes to its carcinogenicity. Finally, we describe the potential for a novel concept of creating ecosystems over asbestos landfills ('activated landfills') that utilize nature's chelating ability to degrade this toxic product effectively.
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Metagenomics can be used to identify potential biocontrol agents for invasive species and was used here to identify candidate species for biocontrol of an invasive club moss in New Zealand. Profiles were obtained for Selaginella kraussiana collected from nine geographically disjunct locations in Northern New Zealand. These profiles were distinct from those obtained for the exotic club moss Selaginella moellendorffii and the native club mosses Lycopodium deuterodensum and Lycopodium volubile also collected in Northern New Zealand. Fungi and bacteria implicated elsewhere in causing plant disease were identified on plants of Selaginella that exhibited signs of necrosis. Most notably, high densities of sequence reads from Xanthomonas translucens and Pseudomonas syringae were associated with some populations of Selaginella but not Lycopodium. Since these bacteria are already in use as biocontrol agents elsewhere, further investigation into their potential as biocontrol of Selaginella in New Zealand is suggested.
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Metagenoma , Selaginellaceae/genética , Espécies Introduzidas , Pseudomonas syringae/patogenicidade , Selaginellaceae/microbiologia , Controle de Plantas Daninhas/métodos , Xanthomonas/patogenicidadeRESUMO
This report is based upon a clinical case series describing five patients who volitionally adultered cannabis with a variety of compounds that shared a common trait-cholinergic modulation. They included a nicotinic agonist, muscarinic antagonist and antiacetylcholinesterase compounds. Some of these compounds (e.g. tobacco) are known to exert pharmacokinetic effects upon cannabinoids (e.g. improved drug absorption). Contrarily, our patients claimed that the compounds altered pharmacodynamic 'cannabimimetic' effects. The case series was supported by forensic identification of adulterants and by use of a symptom causality algorithm. A survey of the gray literature and drug culture web sites indicated that the case series portended a larger social phenomenon. Furthermore, many clinical reports, animal behaviour studies and in vitro mechanistic studies substantiated our observations. In conclusion, we provide empirical data regarding a new trend in the drug culture-cholinergic modulation of cannabinoid effects-that presents new research directions.
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Acetilcolina/farmacologia , Ácidos Araquidônicos/farmacologia , Moduladores de Receptores de Canabinoides/farmacologia , Abuso de Maconha/epidemiologia , Alcamidas Poli-Insaturadas/farmacologia , Receptores Colinérgicos/efeitos dos fármacos , Adulto , Endocanabinoides , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Mangrove forests of a single trees species, Avicennia marina subsp. australasica are widespread in the upper North Island of New Zealand, but there is little available information on the diversity of epiphytes such as lichens within them. A survey of 200 trees from 20 mangrove sites recorded a total of 106 lichen species from 45 genera. Two of these species are considered to be 'Threatened', five 'At Risk' and 27 'Data Deficient'. Multiple regression indicated that tree diameter (DBH) and mean annual rain days positively influenced site species richness. Multidimensional scaling showed that sites from the same geographical region generally formed distinct clusters. Redundancy analysis indicated that mean annual wet days, latitude and DBH measurably influenced species composition.