Biology subjects

Mundra, S.

Publications and source records attributed to Mundra, S..

3 recordsLinked to original sources

bioRxiv2022

Divergent TLR2 and TLR4 activation by fungal spores and species diversity in dust from waste-sorting plants

1.This manuscript presents the results of an exploratory study on the relationships between NFkB (Nuclear Factor Kappa Chain Enhancer of B-cells) response through TLRs activation by dust characterized by fungal spore concentrations and species diversity. Personal total dust samples were collected from Norwegian waste sorting plants and then characterized for fungal spores and fungal species diversity, as well as for other bioaerosol components, including endotoxins and actinobacteria. The ability of the dust to induce an NFkB response by activating Toll-like receptors 2 (TLR2) and 4 (TLR4) in vitro was evaluated as well as the relationship between such responses and quantifiable bioaerosol components. The average concentrations of bioaerosols were 7.23 mg total dust m-3, 4.49x105 fungal spores m-3, 814 endotoxin units m-3, and 0.6x105 actinobacteria m-3. The mean diversity measurements were 326; 0.59 and 3.39 for fungal richness, evenness, and Shannon Index, respectively. Overall, fungal OTUs belonging to the Ascomycotina phylum were most abundant (55%), followed by Basidiomycota (33%) and Mucormycota (3%). All samples induced significant NFkB responses through TLR2 and TLR4 activation. While fungal spore levels were positively associated with TLR2 and TLR4 activation, there was a trend that fungal species richness was negatively associated with the activation of these receptors. This observation supports the existence of divergent immunological responses relationship between fungal spore levels and fungal species diversity. Such relationships seem to be described for the first time for dust from waste facilities.

microbiology↗

bioRxiv2020

Can root-associated fungi mediate the impact of abiotic conditions on the growth of a High Arctic herb?

Arctic plants are affected by many stressors. Root-associated fungi are thought to influence plant performance in stressful environmental conditions. However, the relationships are not transparent; do the number of fungal partners, their ecological functions and community composition mediate the impact of environmental conditions and/or influence host plant performance? To address these questions, we used a common arctic plant as a model system: Bistorta vivipara. Whole plants (including root system) were collected from nine locations in Spitsbergen (n=214). Morphometric features were measured as a proxy for performance and combined with metabarcoding datasets of their root-associated fungi (amplicon sequence variants, ASVs), edaphic and meteorological variables. Seven biological hypotheses regarding fungal influence on plant measures were tested using structural equation modelling. The best-fitting model revealed that local temperature affected plants both directly (negatively aboveground and positively below-ground) and indirectly - mediated by fungal richness and the ratio of symbio- and saprotrophic ASVs. Fungal community composition did not impact plant measurements and plant reproductive investment did not depend on any fungal parameters. The lack of impact of fungal community composition on plant performance suggests that the functional importance of fungi is more important than their identity. The influence of temperature on host plants is therefore complex and should be examined further.

microbiology↗

bioRxiv2020

GlobalFungi: Global database of fungal records from high-throughput-sequencing metabarcoding studies

Fungi are key players in vital ecosystem services, spanning carbon cycling, decomposition, symbiotic associations with cultural and wild plants and pathogenicity. The high importance of fungi in the ecosystem processes contrasts with the incompleteness of understanding of the patterns of fungal biogeography and the environmental factors that drive it. To close this gap of knowledge, we have here collected and validated data published on the composition of soil fungal communities in terrestrial environments including soil and plant-associated habitats and made them publicly accessible through a user interface at http://globalfungi.com. The GlobalFungi database contains over 650 million observations of fungal sequences across >20 000 samples with geographical locations and additional metadata contained in 207 original studies with millions of unique sequence variants of the fungal internal transcribed spacers (ITS) 1 and 2 representing fungal species and genera. As it is, the study represents the most comprehensive atlas of fungal distribution on the global scale open to further additions.

ecology↗