The Abundance and Diversity of Fungi in a Hypersaline Microbial Mat from Guerrero Negro, Baja California, México

Abstract

The abundance and diversity of fungi were evaluated in a hypersaline microbial mat from Guerrero Negro, México, using a combination of quantitative polymerase chain reaction (qPCR) amplification of domain-specific primers, and metagenomic sequencing. Seven different layers were analyzed in the mat (Layers 1–7) at single millimeter resolution (from the surface to 7 mm in depth). The number of copies of the 18S rRNA gene of fungi ranged between 106 and 107 copies per g mat, being two logarithmic units lower than of the 16S rRNA gene of bacteria. The abundance of 18S rRNA genes of fungi varied significantly among the layers with layers 2–5 mm from surface contained the highest numbers of copies. Fifty-six fungal taxa were identified by metagenomic sequencing, classified into three different phyla: Ascomycota, Basidiomycota and Microsporidia. The prevalent genera of fungi were Thermothelomyces, Pyricularia, Fusarium, Colletotrichum, Aspergillus, Botrytis, Candida and Neurospora. Genera of fungi identified in the mat were closely related to genera known to have saprotrophic and parasitic lifestyles, as well as genera related to human and plant pathogens and fungi able to perform denitrification. This research suggests that fungi in the mat may participate in nutrient recycling, modification of community composition through parasitic activities, and denitrification.

Millimeter-scale vertical partitioning of nitrogen cycling in hypersaline mats reveals prominence of genes encoding multi-heme and prismane proteins

“…This is perhaps not surprising as Layer 1 was characterized microscopically as consisting primarily of diatoms and exopolysaccharides and was the least cohesive and least dense of all layers examined. Moreover, the low numbers of microorganisms detected in Layer 1 is consistent with a recent study based on quantification of eukaryotic microorganisms in the same microbial mat [35]. Microbial mats are well known for their capacity to fix nitrogen and there have been many studies of the distribution of the genes responsible.…”

Using RNA-Sequencing Data to Examine Tissue-Specific Garlic Microbiomes

“…As previously described, Kraken2 generated accurate taxonomic identification for bacteria with very fast speed [37,38]. However, only a few studies have used Kraken2 for fungal and viral microbiome studies [39,40]. In this study, we have shown that Kraken2 is a powerful tool for identifying bacteria, fungi, and viruses.…”

Contrasted microbial community colonization of a bauxite residue deposit marked by a complex geochemical context

“…Dothideomycetes constitute almost the entire fungal community in microbial mats from soda lakes and are also found in microbial mats from hypersaline and iron-rich habitats (Gerea et al, 2012;Maza-Márquez et al, 2021;Salano et al, 2017). In microbial mats, fungi play a crucial role in nutrient recycling by decomposing complex carbohydrates into simpler compounds that fuel chemoheterotrophic species (Carreira et al, 2020).…”