Genomic features of lichen-associated black fungi
- Author:
- Keller V., Calchera A., Otte J. & Schmitt I.
- Year:
- 2025
- Journal:
- IUBMB Life
- Pages:
- 77: e2934 [17 p.]
- Url:
- https://doi.org/10.1002/iub.2934
Lichens are mutualistic associations consisting of a primary fungal host, and
one to few primary phototrophic symbiont(s), usually a green alga and/or a
cyanobacterium. They form complex thallus structures, which provide unique
and stable habitats for many other microorganisms. Frequently isolated from
lichens are the so-called black fungi, or black yeasts, which are mainly characterized
by melanized cell walls and extremophilic lifestyles. It is presently
unclear in which ways these fungi interact with other members of the lichen
symbiosis. Genomic resources of lichen-associated black fungi are needed to
better understand the physiological potential of these fungi and shed light on
the complexity of the lichen consortium. Here, we present high-quality
genomes of 14 black fungal lineages, isolated from lichens of the rock-dwelling
genus Umbilicaria. Nine of the lineages belong to the Eurotiomycetes
(Chaetothyriales), four to the Dothideomycetes, and one to the Arthoniomycetes,
representing the first genome of a black fungus in this class. The
PacBio-based assemblies are highly contiguous (5–42 contigs per genome,
mean coverage of 79–502, N50 of 1.0–7.3 mega-base-pair (Mb), Benchmarking
Universal Single-Copy Orthologs (BUSCO) completeness generally ≥95.4%).
Most contigs are flanked by a telomere sequence, suggesting we achieved near
chromosome-level assemblies. Genome sizes range between 26 and 44 Mb.
Transcriptome-based annotations yielded 11,000–18,000 genes per genome.
We analyzed genome content with respect to repetitive elements, biosynthetic
genes, and effector genes. Each genome contained a polyketide synthase gene
related to the dihydroxynaphthalene-melanin pathway. This research provides
insights into genome content and metabolic potential of these relatively
unknown, but frequently encountered lichen associates.
Keywords: biosynthetic gene clusters, diversity, funannotate, melanin, PacBio, phylogenetics, symbiosis.
- Id:
- 37410
- Submitter:
- zpalice
- Post_time:
- Thursday, 26 December 2024 11:44