Fungi comprise a great diversity of species with distinct ecological functions and lifestyles. Similar to other eukaryotes, fungi rely on interactions with prokaryotes and one of the most important symbiotic events was the acquisition of mitochondria. Mitochondria are organelles found in eukaryotic cells whose main function is to generate energy through aerobic respiration. Mitogenomes (mtDNAs) are double-stranded circular or linear DNA from mitochondria that may contain core genes and accessory elements that can be replicated, transcribed, and independently translated from the nuclear genome. Despite their importance, investigative studies on the diversity of fungal mitogenomes are scarce. Herein, we have evaluated 788 curated fungal mitogenomes available at NCBI database to assess discrepancies and similarities among them and to better understand the mechanisms involved in fungal mtDNAs variability. From a total of 12 fungal phyla, four do not have any representative with available mitogenomes, which highlights the underrepresentation of some groups in the current available data. We selected representative and non-redundant mitogenomes based on the threshold of 90% similarity, eliminating 81 mtDNAs. Comparative analyses revealed considerable size variability of mtDNAs with a difference of up to 260 kb in length. Furthermore, variation in mitogenome length and genomic composition are generally related to the number and length of accessory elements (introns, HEGs, and uORFs). We identified an overall average of 8.0 (0–39) introns, 8.0 (0–100) HEGs, and 8.2 (0–102) uORFs per genome, with high variation among phyla. Even though the length of the core protein-coding genes is considerably conserved, approximately 36.3% of the mitogenomes evaluated have at least one of the 14 core coding genes absent. Also, our results revealed that there is not even a single gene shared among all mitogenomes. Other unusual genes in mitogenomes were also detected in many mitogenomes, such as dpo and rpo, and displayed diverse evolutionary histories. Altogether, the results presented in this study suggest that fungal mitogenomes are diverse, contain accessory elements and are absent of a conserved gene that can be used for the taxonomic classification of the Kingdom Fungi.
Many studies have investigated how social insects behave when a parasite is introduced into their colonies. These studies have been conducted in the laboratory, and we still have a limited understanding of the dynamics of ant-parasite interactions under natural conditions. Here we consider a specialized parasite of ant societies (Ophiocordyceps camponoti-rufipedis infecting Camponotus rufipes) within a rainforest. We first established that the parasite is unable to develop to transmission stage when introduced within the host nest. Secondly, we surveyed all colonies in the studied area and recorded 100% prevalence at the colony level (all colonies were infected). Finally, we conducted a long-term detailed census of parasite pressure, by mapping the position of infected dead ants and foraging trails (future hosts) in the immediate vicinity of the colonies over 20 months. We report new dead infected ants for all the months we conducted the census – at an average of 14.5 cadavers/month/colony. Based on the low infection rate, the absence of colony collapse or complete recovery of the colonies, we suggest that this parasite represents a chronic infection in the ant societies. We also proposed a “terminal host model of transmission” that links the age-related polyethism to the persistence of a parasitic infection.
Gibellula (Cordycipitaceae, Hypocreales) is frequently observed growing on spiders, but little is known about their host range. One of the greatest challenges in describing these interactions is identifying the host, since the fungus often rapidly consumes the parasitised spiders and destroys important diagnostic taxonomic traits. Additionally, the global diversity of Gibellula remains unclear, as does the natural history and phylogenetic relationships of most of the species. Herein, we performed an extensive investigation on the species of Gibellula, reconstructed the most complete molecular phylogeny of the genus in the context of Cordycipitaceae, and performed a systematic review in order to provide the foundations towards a better understanding of the genus. Therefore, we have performed an integrative study to investigate the life history of the genus and to disentangle the questionable number of valid species proposed over time. We provided novel molecular data for published species that had not been sequenced before, such as G. mirabilis and G. mainsii, and evaluated all the original and modern morphological descriptions. In addition, we presented its global known distribution and compiled all available molecular data. We suggested a set of terms and morphological traits that should be considered in future descriptions of the genus and that a total of 31 species should be considered as accepted.
The potential applications of fungi in the development of new biomaterials derived from fungal mycelium have captured the attention from both the scientific community and the society. The notable ability of mycelium networks to self-construct and aggregate can be used to produce diverse biomaterials. These biomaterials can be created in a pure state, or both in conjunction with other organic/inorganic compounds. Recent advancements in mycomaterials have gained attention due to their sustainability and mechanical, thermogravimetric, and compression properties. Such properties contribute to reducing the reliance on environmentally problematic substrates within the industry. After a standardized and comprehensive review of publications on mycomaterials across different fields, such as biology, health, agriculture, engineering, and material sciences, we detected that publications on this theme are utterly scattered. This critical review enabled us to also propose a novel classification system for these fungal-derived materials to help to structure and standardize this emerging transdisciplinary field of knowledge.
Fungal parasites that infect spiders can affect their survival and potentially their behaviour. The genus Gibellula (Ascomycota, Cordycipitaceae) infects arachnids, and due to difficulties in identifying hosts after fungal sporulation, its ecology and spider host diversity are poorly understood. Herein, we propose a new species of Gibellula from the Brazilian Atlantic Forest: Gibellula aurea, which parasitizes two spider families (Anyphaenidae and Corinnidae). Gibellula aurea exhibits characteristic golden-yellow hyphae that completely cover hosts and white conidiophores emerging along synnemata or directly from hosts. Molecular identification was performed by sequencing the small and large nuclear ribosomal subunits, translation elongation factor, and RNA polymerase II second largest subunit regions, and reconstructing multigene phylogenetic trees. Maximum Likelihood and Bayesian Inference phylogenies demonstrate that G. aurea forms a well-supported clade closer to G. flava, G. gamsii, G. leiopus, G. longispora, G. pigmentosinum, and G. pulchra. The phylogenetic reconstruction displayed herein represents the most comprehensive phylogeny for this genus to date. Spider hosts parasitized by G. aurea have been invariably found attached underneath leaves in vegetation, regardless of the identity of the infected hosts. The consistency of the death locations of G. aurea hosts indicates recurrent behaviour given the habitat heterogeneity of these host groups. Nevertheless, it is still unclear to what extent the place where hosts die can favour parasite fitness.