39 research outputs found
Biodiversity of leaf litter fungi in streams along a latitudinal gradient
Global patterns of biodiversity have emerged for soil microorganisms, plants and animals, and the extraordinary significance of microbial functions in ecosystems is also well established. Virtually unknown, however, are large- scale patterns of microbial diversity in freshwaters, although these aquatic ecosystems are hotspots of biodiversity and biogeochemical processes. Here we report on the first large-scale study of biodiversity of leaf-litter fungi in streams along a latitudinal gradient unravelled by Illumina sequencing. The study is based on fungal commu- nities colonizing standardized plant litter in 19 globally distributed stream locations between 69°N and 44°S. Fungal richness suggests a hump-shaped distribution along the latitudinal gradient. Strikingly, community com- position of fungi was more clearly related to thermal preferences than to biogeography. Our results suggest that identifying differences in key environmental drivers, such as temperature, among taxa and ecosystem types is critical to unravel the global patterns of aquatic fungal diversity
Global patterns and drivers of ecosystem functioning in rivers and riparian zones
AbstractRiver ecosystems receive and process vast quantities of terrestrial organic carbon, the fate of which depends strongly on microbial activity. Variation in and controls of processing rates, however, are poorly characterized at the global scale. In response, we used a peer-sourced research network and a highly standardized carbon processing assay to conduct a global-scale field experiment in greater than 1000 river and riparian sites. We found that Earth’s biomes have distinct carbon processing signatures. Slow processing is evident across latitudes, whereas rapid rates are restricted to lower latitudes. Both the mean rate and variability decline with latitude, suggesting temperature constraints toward the poles and greater roles for other environmental drivers (e.g., nutrient loading) toward the equator. These results and data set the stage for unprecedented “next-generation biomonitoring” by establishing baselines to help quantify environmental impacts to the functioning of ecosystems at a global scale.Abstract
River ecosystems receive and process vast quantities of terrestrial organic carbon, the fate of which depends strongly on microbial activity. Variation in and controls of processing rates, however, are poorly characterized at the global scale. In response, we used a peer-sourced research network and a highly standardized carbon processing assay to conduct a global-scale field experiment in greater than 1000 river and riparian sites. We found that Earth’s biomes have distinct carbon processing signatures. Slow processing is evident across latitudes, whereas rapid rates are restricted to lower latitudes. Both the mean rate and variability decline with latitude, suggesting temperature constraints toward the poles and greater roles for other environmental drivers (e.g., nutrient loading) toward the equator. These results and data set the stage for unprecedented “next-generation biomonitoring” by establishing baselines to help quantify environmental impacts to the functioning of ecosystems at a global scale
Global patterns and drivers of ecosystem functioning in rivers and riparian zones
Os ecossistemas fluviais recebem e processam grandes quantidades de carbono orgânico terrestre, cujo destino depende fortemente da atividade microbiana. A variação e o controle das taxas de processamento, no entanto, são mal caracterizados à escala global. Em resposta, utilizamos uma rede de pesquisa de pares e um ensaio de processamento de carbono altamente padronizado para conduzir um experimento de campo em escala global em mais de 1.000 locais fluviais e ribeirinhos. Descobrimos que os biomas da Terra têm assinaturas distintas de processamento de carbono. O processamento lento é evidente em todas as latitudes, enquanto as taxas rápidas são restritas às latitudes mais baixas. Tanto a taxa média como a variabilidade diminuem com a latitude, sugerindo restrições de temperatura em direção aos pólos e papéis maiores para outros fatores ambientais (por exemplo, carga de nutrientes) em direção ao equador. Estes resultados e dados preparam o terreno para uma “biomonitorização de próxima geração” sem precedentes, estabelecendo linhas de base para ajudar a quantificar os impactos ambientais no funcionamento dos ecossistemas à escala global.River ecosystems receive and process vast quantities of terrestrial organic carbon, the fate of which depends strongly on microbial activity. Variation in and controls of processing rates, however, are poorly characterized at the global scale. In response, we used a peer-sourced research network and a highly standardized carbon processing assay to conduct a global-scale field experiment in greater than 1000 river and riparian sites. We found that Earth’s biomes have distinct carbon processing signatures. Slow processing is evident across latitudes, whereas rapid rates are restricted to lower latitudes. Both the mean rate and variability decline with latitude, suggesting temperature constraints toward the poles and greater roles for other environmental drivers (e.g., nutrient loading) toward the equator. These results and data set the stage for unprecedented “next-generation biomonitoring” by establishing baselines to help quantify environmental impacts to the functioning of ecosystems at a global scale
Investigating the likely association between genetic ancestry and COVID-19 manifestations
AbstractBackgroundThe novel coronavirus: severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread rapidly throughout the world leading to catastrophic consequences. However, SARS-CoV-2 infection has shown discernible variability across the globe. While in some countries people are recovering relatively quickly, in others, recovery times have been comparatively longer and number of individuals succumbing to it are high. This variability in coronavirus disease 2019 (COVID-19) susceptibility is suggestive of a likely association between the genetic-make up of affected individuals modulated by their ancestry and the severity of COVID-19 manifestations.ObjectiveIn this study, we aimed to evaluate the potential association between an individual’s genetic ancestry and the extent of COVID-19 disease presentation employing Europeans as the case study. In addition, using a genome wide association (GWAS) approach we sought to discern the putative single nucleotide polymorphism (SNP) markers and genes that may be likely associated with differential COVID-19 manifestations by comparative analyses of the European and East Asian genomes.MethodTo this end, we employed 10,215 ancient and modern genomes across the globe assessing 597,573 SNPs obtained from the databank of Dr. David Reich, Harvard Medical School, USA to evaluate the likely correlation between European ancestry and COVID-19 manifestations. Ancestry proportions were determined using qpAdm program implemented in AdmixTools v5.1. Pearson’s correlation coefficient (r) between various ancestry proportions of European genomes and COVID-19 death/recovery ratio was calculated and its significance was statistically evaluated. Genome wide association study (GWAS) was performed in PLINK v1.9 to investigate SNPs with significant allele frequency variations among European and East Asian genomes that likely correlated with differential COVID-19 infectivity.ResultsWe found significant positive correlation (r=0.58, P=0.03) between West European hunter gatherers (WHG) ancestral fractions and COVID-19 death/recovery ratio for data as of 5th April 2020. This association discernibly amplified (r=0.77, P=0.009) upon reanalyses based on data as of 30th June 2020, removing countries with small sample sizes and adding those that are a bridge between Europe and Asia. Using GWAS we further identified 404 immune response related SNPs by comparing publicly available 753 genomes from various European countries against 838 genomes from various Eastern Asian countries. Prominently, we identified that SNPs associated with immune-system related pathways such as interferon stimulated antiviral response, adaptive and innate immune system and IL-6 dependent immune responses show significant differences in allele frequencies [Chi square values (≥1500; P≈0)] between Europeans and East Asians.ConclusionSo far, to the best of our knowledge, this is the first study investigating the likely association between host genetic ancestry and COVID-19 severity. These findings improve our overall understanding of the putative genetic modifiers of COVID-19 clinical presentation. We note that the development of effective therapeutics will benefit immensely from more detailed analyses of individual genomic sequence data from COVID-19 patients of varied ancestries.</jats:sec
Investigating the likely association between genetic ancestry and COVID-19 manifestation (Preprint)
UNSTRUCTURED
The novel coronavirus 2019-nCoV/SARS-CoV-2 infection has shown discernible variability across the globe. While in some countries people are recovering relatively quicker, in others, recovery times have been comparatively longer and numbers of those succumbing to it high. In this study, we aimed to evaluate the likely association between an individual’s ancestry and the extent of COVID-19 manifestation employing Europeans as the case study. We employed 10,215 ancient and modern genomes across the globe assessing 597,573 single nucleotide polymorphisms (SNPs). Pearson’s correlation coefficient (r) between various ancestry proportions of European genomes and COVID-19 death/recovery ratio was calculated and its significance was statistically evaluated. We found significant positive correlation (p=0.03) between European Mesolithic hunter gatherers (WHG) ancestral fractions and COVID-19 death/recovery ratio and a marginally significant negative correlation (p=0.06) between Neolithic Iranian ancestry fractions and COVID-19 death/recovery ratio. We further identified 404 immune response related single nucleotide polymorphisms (SNPs) by comparing publicly available 753 genomes from various European countries against 838 genomes from various Eastern Asian countries in a genome wide association study (GWAS). Prominently, we identified that SNPs associated with Interferon stimulated antiviral response, Interferon-stimulated gene 15 mediated antiviral mechanism and 2′-5′ oligoadenylate synthase mediated antiviral response show large differences in allele frequencies between Europeans and East Asians. Overall, to the best of our knowledge, this is the first study evaluating the likely association between genetic ancestry and COVID-19 manifestation. While our current findings improve our overall understanding of the COVID-19, we note that the development of effective therapeutics will benefit immensely from more detailed analyses of individual genomic sequence data from COVID-19 patients of varied ancestries.
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Bioactive Potential of Lentinus squarrosulus and Termitomyces clypeatus from the Southwestern region of India
The antioxidants derived from biological sources are generally regarded as safe than synthetic ones owing to their less or no adverse effects. Wild mushrooms being a potential source of nutrients as well as antioxidants, bioactive properties of uncooked and cooked wood-inhabiting Lentinus squarrosulus andtermite mound-inhabiting Termitomyces clypeatus have been compared. Both mushrooms showed appreciable antioxidant potential, which is influenced by their bioactive principles (total phenolics, tannins, flavonoids and vitamin C) and proximal properties (crude protein, crude lipid, crude fibre and carbohydrates). These mushrooms were devoid of trypsin inhibition and hemagglutinin activity. Uncooked as well as cooked mushrooms with adequate nutritional components serve as sources of potential antioxidant to combat many human ailments. The present study and recent perspectives on nutraceuticals of macrofungi denote L. squarrosulus and T. clypeatus as the high-value nutraceutical sources in Southwestern India
Diurnal periodicity of conidia of aquatic hyphomycetes in water and entrapment on latex-coated slides in two South Indian streams
Aquatic hyphomycete conidial trapping efficiency by the banyan (F. benghalensis L.) latex-coated glass slides was tested diurnally (3 h intervals) in the Western Ghats (Sampaje) and west coast (Konaje) streams in relation to abiotic factors (humidity, air temperature and water temperature). The conidial trapping efficiency of latex-coated slides was compared with plain glass slides and drift conidia in water. Three methods of assessment showed higher species richness, conidial richness and diversity in Sampaje than in Konaje stream. In both streams, species richness, conidial richness and diversity in latex-coated slides were the highest followed by conidia in water and plain slides. Three-way ANOVA revealed significant differences in overall species and conidial richness between the streams, sampling methods and time of sampling (p < 0.001). Multiple comparisons by Holm–Sidak test revealed significant differences in overall species and conidial richness between Sampaje and Konaje (p < 0.001); latex-coated slides and plain slides (p < 0.001); latex-coated slides and water filtration (p < 0.001); plain slides and water filtration (p < 0.001). Total species, total conidia and diversity assessed by the three methods peaked during 12 am–3 am in Sampaje stream, while during 3 am–6 am in Konaje stream. Cooler conditions due to relatively low water temperature favoured higher diversity of aquatic hyphomycetes in Sampaje than in Konaje stream. The three methods employed in the present study were not biased towards scolecoid or stauroid conidia. The top five species in both streams was composed of both types of conidia corroborating earlier annual or biannual studies in Konaje and Sampaje streams. Thus, assessment of population of aquatic hyphomycetes using banyan latex-coated slides will be advantageous over plain slides and drift conidia in streams
Bioactive Potential of <i>Lentinus squarrosulus</i> and <i>Termitomyces clypeatus</i> from the Southwestern region of India
120-131The antioxidants derived from biological sources are generally regarded as safe than synthetic ones owing to their less or no adverse effects. Wild mushrooms being a potential source of nutrients as well as antioxidants, bioactive properties of uncooked and cooked wood-inhabiting Lentinus squarrosulus andtermite mound-inhabiting Termitomyces clypeatus have been compared. Both mushrooms showed appreciable antioxidant potential, which is influenced by their bioactive principles (total phenolics, tannins, flavonoids and vitamin C) and proximal properties (crude protein, crude lipid, crude fibre and carbohydrates). These mushrooms were devoid of trypsin inhibition and hemagglutinin activity. Uncooked as well as cooked mushrooms with adequate nutritional components serve as sources of potential antioxidant to combat many human ailments. The present study and recent perspectives on nutraceuticals of macrofungi denote L. squarrosulus and T. clypeatus as the high-value nutraceutical sources in Southwestern India
