One Name – One Fungus: The Influence of Photosynthetic Partners on the Taxonomy and Systematics of Lichenized Fungi

Abstract

Lichens are fungi (mycobionts) that form symbiotic associations with photoautotrophic prokaryotes or eukaryotes (photobionts); however, some species can exchange photosynthetic partners during their lifecycles. This phenomenon modifies the morphology of lichens and consequently influences the taxonomy of lichenized fungi. Here, a few such cases in which the photobionts influenced the taxonomy and systematics of lichenized fungi are reviewed. Two different morphotypes of the same species – known as photomorphs – were classified as different species and sometimes different genera. Moreover, different types of photobionts and the absence or presence (optional lichenization) of an alga in the thallus were believed to be diagnostic characters for discriminating genera. However, the taxonomy and systematics of lichens are based always, according to Article F.1.1. of the <em>International </em><em>Code of Nomenclature for Algae, Fungi, and Plants</em>, on the fungal partner and only one name is applied.

Analysis of the Gut Mycobiome in Adult Patients with Type 1 and Type 2 Diabetes Using Next-Generation Sequencing (NGS) with Increased Sensitivity—Pilot Study

“…At L2 (phylum), we identified OTUs corresponding to 15 types, but only 4 types reached the percentage of above 1% (Basidiomycota, Ascomycota, Chlorophyta, and an unidentified phylum). Chlorophyta is a taxon of green algae belonging to eukaryotic organisms, selected species of which can form symbiotic forms with fungi, known as lichens [ 30 ]. Due to the fact that this phylum was identified in the course of sequencing, probably due to the similarity of the selected DNA fragment to fungal sequences, it will not be analyzed later in this study.…”

Symbiont‐specific responses to environmental cues in a threesome lichen symbiosis

“…In contrast, cyanobacterial cell envelopes are made of peptidoglycan encapsulated in a polysaccharide sheath (Hoiczyk & Hansel, 2000; Woitzik et al, 1988). Fourth, although the formation of various chemotypes also depends on environmental factors (Cornejo et al, 2017; Culberson, 1986; Hale, 1957), photobiont type can affect the composition and content of carbon‐based secondary compounds of lichens and chloromorphs have been reported to contain different secondary metabolites than cyanomorphs of the same fungal species (Kukwa et al, 2020; Tønsberg & Holtan‐Hartwig, 1983). The different partners involved in the symbiosis can individually produce different secondary metabolites, and certain fungal metabolites are only produced in symbiosis with a specific photosynthetic partner.…”

Symbiont-specific responses to environmental cues in a threesome lichen symbiosis

“…In contrast, cyanobacterial cell envelopes are made of peptidoglycan encapsulated in a polysaccharide sheath (Hoiczyk & Hansel, 2000;Woitzik et al, 1988). Fourth, although the formation of various chemotypes also depends on environmental factors (Cornejo et al, 2017;Culberson, 1986;Hale, 1957), photobiont type can affect the composition and content of carbon-based secondary compounds of lichens and chloromorphs have been reported to contain different secondary metabolites than cyanomorphs of the same fungal species (Kukwa et al, 2020;Tønsberg & Holtan-Hartwig, 1983). The different partners involved in the symbiosis can individually produce different secondary metabolites, and certain fungal metabolites are only produced in symbiosis with a specific photosynthetic partner.…”