Species Of Tremella Research Articles

A new species of Tremella from India

A new Tremella species was collected and described from Kerala State, India. Morphological features along with molecular data confirmed the novelty of the species. The new species T. poilkavensis is characterised by amber brown to blackish brown basidiocarp, stalked basidia, conidiospores budding off from basidia, growth on ascomata of Biscogniauxia species and presence of host hyphae within the basidiocarp.

Tremella macrobasidiata and Tremella variae have abundant and widespread yeast stages in Lecanora lichens.

Dimorphism is a widespread feature of tremellalean fungi in general, but a little-studied aspect of the biology of lichen-associated Tremella. We show that Tremella macrobasidiata and Tremella variae have an abundant and widespread yeast stage in their life cycles that occurs in Lecanora lichens. Their sexual filamentous stage is restricted to a specific lichen: T. macrobasidiata only forms basidiomata on Lecanora chlarotera hymenia and T. variae only on Lecanora varia thalli. However, the yeast stage of T. macrobasidiata is less specific and can occur in L. varia lichens, whilst all life stages of T. variae may be specific to L. varia. Contrary to the hyphal stages, the yeasts are distributed across the thalli and hymenia of Lecanora lichens, and not limited to specimens with basidiomata. Tremella macrobasidiata was present in all studied L. chlarotera, and in 59% of L. varia specimens. Only in 8% of the L. varia thalli could none of the two Tremella species be detected. Our results indicate that lichen-associated Tremella may be much more abundant and widespread than previously assumed leading to skewed estimations about their distribution ranges and lichen specificity, and raise new questions about their biology, ecology and function in the symbiosis.

Four new species of Tremella (Tremellales, Basidiomycota) based on morphology and DNA sequence data.

In the present study, a total of 33 Tremella specimens in China were collected and examined using molecular phylogenetic analysis based on a combined sequence dataset of the nuc rDNA internal transcribed spacer (ITS) region and nuc 28S rDNA D1/D2 domain in conjunction with the morphological characters. Four new species, namely Tremellabasidiomaticola, T.cheejenii, T.erythrina, and T.salmonea, are newly described based on their distinct phylogenetic relationships and the comparison of morphological characters with known Tremella species. Our results indicate a high species diversity of Tremella waiting to be discovered.

Two Basidiomycete Fungi in the Cortex of Wolf Lichens

Since the late 1800s, mycologists have been detecting fungi above and beyond the assumed single fungus in lichen thalli [1-6]. Over the last century, these fungi have been accorded roles ranging from commensalists to pathogens. Recently, Cyphobasidiales yeasts were shown to be ubiquitous in the cortex layer of many macrolichens [7], but for most species, little is known of their cellular distribution and constancy beyond visible fruiting structures. Here, we demonstrate the occurrence of an additional and distantly related basidiomycete, Tremella, in 95% of studied thalli in a global sample of one of the most intensively studied groups of lichens, the wolf lichens (genus Letharia). Tremella species are reported froma wide range of lichen genera [8], but until now, their biology was deduced from fruiting bodies (basidiomata) formed on lichen thalli. Based on this, they have been thought to be uncommon to rare, to occur exclusively in a hyphal form, and to be parasitic on the dominant fungal partner [9, 10]. We show that, in wolf lichens, Tremella occurs as yeast cells also inthalli that lack basidiomata and infer that this is itsdominant stage in nature. We further show that the hyphal stage, when present in Letharia, is inclosecontact with algal cells, challenging the assumption that lichen-associated Tremella species are uniformly mycoparasites. Our results suggest that extent of occurrence and cellular interactions of known fungi within lichens have historically been underestimated and raise new questions about their function in specific lichen symbioses.

Tremella mayrhoferi, a New Lichenicolous Species on Lecanora allophana

Zamora J.C., Millanes A.M., Etayo J. & Wedin M. 2018: Tremella mayrhoferi, a new lichenicolous species on Lecanora allophana. – Herzogia 31: 666–676.Tremella mayrhoferi, inducing galls on the hymenium of Lecanora allophana, is described. The description is based on molecular, morphological and ecological data of 27 specimens from Finland, Norway, Spain, Sweden, and USA. The new species is easily distinguished from other lichenicolous Tremella species by its characteristic basidia with cells that elongate before the formation of epibasidia, combined with the macromorphology and host selection. Molecular phylogeny suggests that it forms a group with other species growing on Lecanora s. lat. and Lecidea s. lat., which is related to the Tremella species growing on Parmeliaceae, but not to Tremella s. str.

Understanding lichenicolous heterobasidiomycetes: new taxa and reproductive innovations in Tremella s.l.

Four new lichenicolous Tremella species are described and characterized morphologically and molecularly. Tremella celata grows on Ramalina fraxinea, inducing the formation of inconspicuous galls, and having hyphae with incomplete clamps. Tremella endosporogena develops intrahymenially in the apothecia of Lecanora carpinea, having single-celled basidia and clampless hyphae. Tremella diederichiana is the name proposed for a species micromorphologically close to T. christiansenii but inducing the formation of small, pale galls on the thallus and apothecia of Lecidea aff. erythrophaea. Tremella variae grows on Lecanora varia thallus, instead of on the apothecia, as do the other known Tremella species parasitizing Lecanora s.l. Phylogenetic relationships and host specificity of these species are investigated and compared with other taxa that show morphological resemblances, phylogenetic affinities or similar hosts. The formation of mitotic conidia inside old basidia (endospores), which is a poorly known reproductive strategy in the Basidiomycota, is also a distinctive character of Tremella endosporogena. A discussion on the reproductive role and systematic implications of endospores is included.

The genus Tremella (Tremellales, Basidiomycota) in Russia with description of two new species and proposal of one nomenclatural combination

Twenty-two non-lichenicolous species of Tremella are reported from Russia. Detailed descriptions, photographs, illustrations and a dichotomous key for the identification of taxa are provided. Two species, Tremella subalpina and T. griseola, are described as new. One new combination is proposed, and an epitype for Tremella yokohamensis is designated. Molecular phylogenetic reconstructions are presented based on nrITS and nrLSU regions in Bayesian and likelihood analyses. Phylogenetic data were strongly correlated with morphological data and were useful to delimit closely related species.

A new species of Tremella from Macaronesia

Tremella laurisilvae, a species new to science with a parasitic strategy on Biscogniauxia species, is described from the evergreen laurel forests of Macaronesia. The basidiocarps are macroscopically differentiated by finger-like lobes and brown-orange colour. Micromorphological differences with phylogenetically related species are evaluated and its phylogenetic placement in Tremellomycetes is inferred from ITS rDNA sequences. A detailed description, plate with photographs and a key to species from Europe and Macaronesia are provided.

Optimal codons in Tremella fuciformis end in C/G, a strong difference with known Tremella species.

Tremella fuciformis is a popular edible fungus with fruiting bodies that can be produced in large quantities at low costs, while it is easy to transform and cultivate as yeast. This makes it an attractive potential bioreactor. Enhanced heterologous gene expression through codon optimization would be useful, but until now codon usage preferences in T. fuciformis remain unknown. To precisely determine the preferred codon usage of T. fuciformis we sequenced the genome of strain Tr26 resulting in a 24.2 Mb draft genome with 10,040 predicted genes. 3288 of the derived predicted proteins matched the UniProtKB/Swiss-Prot databases with 40% or more similarity. Corresponding gene models of this subset were subsequently optimized through repetitive comparison of alternative start codons and selection of best length matching gene models. For experimental confirmation of gene models, 96 random clones from an existing T. fuciformis cDNA library were sequenced, generating 80 complete CDSs. Calculated optimal codons for the 3288 predicted and the 80 cloned CDSs were highly similar, indicating sufficient accuracy of predicted gene models for codon usage analysis. T. fuciformis showed a strong preference for C and then G at the third base pair position of used codons, while average GC content of predicted genes was slightly higher than the total genome sequence average. Most optimal codons ended in C or G except for one, and an increased frequency of C ending codons was observed in genes with higher expression levels. Surprisingly, the preferred codon usage in T. fuciformis strongly differed from T. mesenterica and C. neoformans. Instead, optimal codon usage was similar to more distant related species such as Ustilago maydis and Neurospora crassa. Despite much higher overall sequence homology between T. fuciformis and T. mesenterica, only 7 out of 21 optimal codons were equal, whereas T. fuciformis shared up to 20 out of 21 optimal codons with other species. Clearly, codon usage in Tremella can differ largely and should be estimated for individual species. The precise identification of optimal and high expression related codons is therefore an important step in the development of T. fuciformis as a bioreactor system.

The phylogenetic analysis of fungi associated with lichenized ascomycete genus Bryoria reveals new lineages in the Tremellales including a new species Tremella huuskonenii hyperparasitic on Phacopsis huuskonenii

The basidiomycete order Tremellales includes many species parasitic on or cohabiting with lichen-forming fungi. In this study, we examined the phylogenetic position of Tremellales obtained from Bryoria thalli using nSSU, 5.8S, and partial nLSU sequence data. Both Bayesian and maximum likelihood analyses revealed the presence of basidiomycetous fungi in three separate clades within Tremellales. Tremellales sp. A and Tremella sp. B exist asymptomatically in Bryoria thalli and should thus be regarded as endolichenic rather than lichenicolous fungi. The third lineage represents a new species and is described here as Tremella huuskonenii. It is hyperparasitic over galls induced by Phacopsis huuskonenii, a lichenicolous fungus growing in Bryoria thalli. We also examined the genetic diversity of Tremella sp. B and Tremella huuskonenii with an extended taxon sampling using ITS and partial nLSU sequence data. For comparison, ITS, GAPDH, and Mcm7 regions were used for phylogenetic analyses of the host lichen specimens. According to our results, phylogenetic structure within the two Tremella species does not appear to correlate with the geographic distribution nor with the phylogeny or the secondary chemistry of the host lichen. However, ITS haplotype analysis of T. huuskonenii revealed some genetic differences between European and North American populations as some haplotypes were more common in Europe than in North America and vice versa.

Diversity of endophytic fungi associated with the foliar tissue of a hemi-parasitic plant Macrosolen cochinchinensis.

Foliar fungal endophytes are an important plant-associated fungal group. However, little is known about these fungi in hemi-parasitic plants, a unique plant group which derive nutrients from living plants of its hosts by haustoria while are photosynthetic to some degree. In this paper, the endophytic fungi in the leaves of a species of hemi-parasitic plant, Macrosolen cochinchinensis, were studied by both culture-dependent and culture-independent methods. By culture-dependent method, a total of 511 isolates were recovered from 452 of 600 leaf fragments (colonization rate = 75.3 %) and were identified to be 51 taxa. Valsa sp. was the most abundant (relative abundance = 38.4 %), followed by Cladosporium sp. 1 (13.5 %), Ulocladium sp. (4.3 %), Phomopsis sp. 2 (3.7 %), Hendersonia sp. (3.5 %), and Diaporthe sp. 4 (3.5 %). The Shannon index (H') of the isolated endophytic fungi was 2.628, indicating a moderate diversity. By culture-independent method, Aspergillus spp., Cladosporium sp., Mycosphaerella sp., Acremonium strictum, and Tremella sp. were detected. To our knowledge, the Tremella species have never been detected as endophytes so far. In addition, a cloned sequence was not similar with any current sequence in the Genbank, which may represent a novel species. Altogether, this study documented endophytic fungal assemble in the leaves of M. cochinchinensis which was worthy of our attention, and may expand our knowledge about endophytic fungi within the photosynthetic tissues of plants.

Yellow Brain Culinary-Medicinal Mushroom, Tremella mesenterica Ritz.:Fr. (Higher Basidiomycetes), is Subjectively but not Objectively Effective for Eradication of Helicobacter pylori: A Prospective Controlled Trial

Inhibitory effects of the higher Basidiomycetes mushrooms, including species of genus Tremella, on the growth of Helicobacter pyroli (Hp) have been described. This study aimed to test T. mesenterica (Tm) efficacy in vivo on eradication of Hp. This IRB-approved study included 52 consenting patients diagnosed with Hp infections. The patients were selected for 10-day treatments with one of the three arms of the protocol, namely, (i) Tm 2 g, (ii) Tm given with omeprazole 20 mg, or (iii) omeprazole 20 mg, clarithromycin 500 mg, and amoxicillin 1000 mg (all regimens given twice daily). The Tm submerged cultivated mycelium in the form of tablets (1 g) was supplied free of charge to patients. Three weeks after completing the therapy, breath testing was assessed for Hp eradication. The patients who took the standard triple therapy had a 70% (n = 14) eradication rate of Hp. Of the patients taking Tm, with and without omeprazole, only one had a breath test indicative of eradication of Hp, p < 0.000. Tm-treated patients had fewer adverse events and equivalent symptomatic relief. Limitations of this study include the brief duration of Tm therapy. Longer treatment might achieve better results, but was judged to be not warranted, so as to not excessively further delay accepted therapy. Ten-day Tm was not found to be effective in vivo in eradicating Hp, whether if given with or without omeprazole. Significant symptomatic relief found among Tm-treated patients suggests that further study of Tm is well justified.

Tremella macrobasidiata (Basidiomycota, Tremellales), a new lichenicolous fungus from the Iberian Peninsula

AbstractTremella macrobasidiata is a proposed new species for a lichenicolous heterobasidomycete strictly parasitizing the hymenium of Lecanora chlarotera. It is reported from Spain, and is characterized by large and particularly variable basidia, rather large basidiospores and the production of asteroconidia, forming brownish to dark green galls in the specific host apothecia. The presence of asteroconidia is discussed. Comparisons with closely related lichenicolous Tremella species are also provided.

Composition and Partial Structure Characterization of Tremella Polysaccharides

Heteropolysaccharides isolated from liquid cultures of nine Tremella species contained 0.3 to 1.2% protein, 2.7 to 5% ash, 0.9 to 3.4% acetyl groups, 76.5 to 84.2% carbohydrates and trace amounts of starch. The polysaccharides in aqueous solution were slightly acidic (pH 5.1 to 5.6). They consisted of the following monomeric sugars: fucose, ribose, xylose, arabinose, mannose, galactose, glucose and glucuronic acid. The backbones of the polysaccharide structures consisted of α-(1 → 3)-links while the side chains were β-linked.

Tremella arachispora: A New Species from Mount Cameroon

A new Tremella species (Basidiomyrota, Tremellales) is described from Cameroon in West Equatorial Africa.

Sugar profile of extracellular polysaccharides from different Tremella species

Heteropolysaccharides isolated from liquid cultures of Tremella species were derivatised to alditol acetates and identified by GLC against derivatised sugar standards. From the sugar profiles it was evident that all of the polysaccharides contained essentially the same sugars but in different ratios. Some of the polysaccharides contained the five carbon sugars—fucose, ribose, xylose and arabinose together with six carbon sugars—mannose, galactose and glucose. The uronic acid content of Tremella heteropolysaccharides also varied according to species. In addition, carbon source (arabinose, xylose, glucose, fructose and galactose) affected the sugar (including uronic acid content) ratio within the polysaccharides.

British Tremella species III: Tremella callunicola sp. nov., T. invasa, T. sarnensis sp. nov., T. simplex & T. versicolor

Five Tremella species associated with corticioid fungi are illustrated and described. Tremella callunicola , an intrahymenial parasite of Aleurodiscus norvegicus , and T. sarnensis , an intrahymenial parasite of Phanerochaete sordida , are described as new. Tremella invasa (associated with Trechispora species), T. simplex (associated with Aleurodiscus amorphus ), and T. versicolor (associated with Peniophora species) are described from British collections.

Phylogenetic analysis of the ballistosporous anamorphic genera Udeniomyces and Bullera, and related basidiomycetous yeasts, based on 18S rDNA sequence

The small subunit nuclear ribosomal DNA (18S rDNA) sequence was determined for twelve species of basidiomycetous anamorphic yeasts, i.e. three species of Udeniomyces, seven species of Bullera, Cryptococcus albidus and Phaffia rhodozyma. For phylogentic analysis, these sequences were aligned with published sequences for 36 other fungal species. Molecular phylogenetic analysis of maximum likelihood and parsimony showed that the 44 species of basidiomycetes analysed were divided into three major lineages. The ballistosporous yeast genera Udeniomyces and Bullera were clearly separated. On the phylogenetic tree, Udeniomyces megalosporus, U. puniceus and U. piricola showed a very close relationship with one another, and composed a lineage with Mrakia frigida, P. rhodozyma and Cystofilobasidium capitatum at high bootstrap confidence level. On the other hand, eight species of Bullera made lineages with selected species of Tremella (Tremellaceae), Filobasidium and Filobasidiella (Filobasidiaceae), Cryptococcus albidus and Trichosporon cutaneum. The molecular phylogeny deduced from the 18S rDNA sequence showed a possibility of heterogeneity among the species of Bullera at the generic level.

Mycoparasitism of Some Tremella Species

The parasitic interaction of Tremella mesenterica, T. encephala and T. mycophaga was studied by light and electron microscopy. The host range of T. mesenterica was tested with Peniophora laeta, Peniophora incarnata, Phlebia radiata, Schizopora paradoxa, Stereum hirsutum and Diatrype stigma. It was demonstrated that T. mesenterica is, at least in vivo, a mycoparasite of the corticiaceous homobasidiomycete Peniophora laeta. Specialized interactive cells of T. mesenterica, T. encephala and T. mycophaga, designated as tremelloid haustorial cells with haustorial filaments, penetrated the cell walls of their respective hosts. A single micropore connected the cytoplasm of the haustorial filament with that of the host cell. The pore membrane appears to be continuous with the plasmalemma of both cells. In older interaction structures, the micropore was often overgrown on the host side by secondary wall formation. In vitro such micropores were present in the interaction of T. mesenterica with Peniophora laeta, P. incarnata and Phlebia radiata but could not be found in the interaction of T. mesenterica with Schizopora paradoxa, Stereum hirsutum and Diatrype stigma. However, only in Peniophora laeta and P. incarnata was the pore domain delimited by a more or less circular arrangement of ER cisternae. Wall thickening may be responsible for the nonmicropore interaction.

Characterization of Three Tremella Species by Isozyme Analysis

Comparative isozyme analyses were performed on three species of Tremella to test their utility as a taxonomic tool and to genetically characterize these fungi. A total of 28 enzymes were surveyed from 86 basidiocarps of T. moriformis, 11 basidiocarps of T. indecorata, and 35 basidiocarps of T. globospora. Twenty-one enzymes (22 loci) retained sufficient activity to be useful in this survey. Twelve enzymes were monomorphic among all three species yet retained species-specific mobilities; of these only 1-glycerophosphate dehydrogenase showed too little interspecies variation to be useful taxonomically. Nine polymorphic enzymes were identified (10 loci); of these only the pair of electromorphs of alcohol dehydrogenase and one electromorph of isocitric dehydrogenase were common to two species.The predominance of monomorphic enzymes and the clear distinction of electromorphs between species suggests isozyme analysis is well suited as a taxonomic tool within the genus.