Residual Polyporoid Clade Research Articles

Two new species of Steccherinum (Polyporales, Basidiomycota) from southern China based on morphology and DNA sequence data.

Two new wood-inhabiting fungal species, Steccherinum hirsutum and S. yunnanense spp. nov., are proposed based on a combination of morphological features and molecular evidence. Sequences of internal transcribed spacer and large subunit region of nuculear ribosomal RNA gene of the studied samples were generated, and phylogenetic analyses were performed using maximum likelihood, maximum parsimony and bayesian inference methods. Steccherinum hirsutum is characterized by an annual growth habit, stipitate basidiocarps with scarlet to red, odontioid hymenial surface, a dimitic hyphal system with clamped generative hyphae negative in Melzer's reaction, and acyanophilous basidiospores measuring 2.5-3.5 × 1.5-2.5 µm. Steccherinum yunnanense is distinguished by resupinate basidiomata with odontioid hymenial surface, a dimitic hyphal system with clamped generative hyphae, strongly encrusted cystidia and ellipsoid, hyaline, thin-walled, smooth basidiospores (3.5-4.5 × 2-3.5 µm). The phylogenetic analyses comfirmed that two new species nest in Steccherinum, in the residual polyporoid clade.

Steccherinum tenuissimum and S. xanthum spp. nov. (Polyporales, Basidiomycota): New species from China.

Two new wood-inhabiting fungal species, Steccherinum tenuissimum and S. xanthum spp. nov. are described based on a combination of morphological features and molecular evidence. Steccherinum tenuissimum is characterized by an annual growth habit, resupinate basidiomata with an odontioid hymenial surface, a dimitic hyphal system with clamped generative hyphae, strongly encrusted cystidia and basidiospores measuring 3–5 × 2–3.5 μm. Steccherinum xanthum is characterized by odontioid basidiomata and a monomitic hyphal system with generative hyphae bearing clamp connections and covering by crystals, colourless, thin-walled, smooth, IKI–, CB–and has basidiospores measuring 2.7–5.5 × 1.8–4.0 μm. Sequences of the ITS and nLSU nrRNA gene regions of the studied samples were generated, and phylogenetic analyses were performed with maximum likelihood, maximum parsimony and Bayesian inference methods. The phylogenetic analyses based on molecular data of ITS + nLSU sequences showed that two new Steccherinum species felled into the residual polyporoid clade. Further investigation was obtained for more representative taxa in Steccherinum based on ITS + nLSU sequences, which demonstrated that S. tenuissimum and S. xanthum were sister to S. robustius with high support (100% BP, 100% BS and 1.00 BPP).

Fungal Adaptation to the Advanced Stages of Wood Decomposition: Insights from the Steccherinum ochraceum.

Steccherinum ochraceum is a white rot basidiomycete with wide ecological amplitude. It occurs in different regions of Russia and throughout the world, occupying different climatic zones. S. ochraceum colonizes stumps, trunks, and branches of various deciduous (seldom coniferous) trees. As a secondary colonizing fungus, S. ochraceum is mainly observed at the late decay stages. Here, we present the de novo assembly and annotation of the genome of S. ochraceum, LE-BIN 3174. This is the 8th published genome of fungus from the residual polyporoid clade and the first from the Steccherinaceae family. The obtained genome provides a first glimpse into the genetic and enzymatic mechanisms governing adaptation of S. ochraceum to an ecological niche of pre-degraded wood. It is proposed that increased number of carbohydrate-active enzymes (CAZymes) belonging to the AA superfamily and decreased number of CAZymes belonging to the GH superfamily reflects substrate preferences of S. ochraceum. This proposition is further substantiated by the results of the biochemical plate tests and exoproteomic study, which demonstrates that S. ochraceum assumes the intermediate position between typical primary colonizing fungi and litter decomposers or humus saprotrophs. Phylogenetic analysis of S. ochraceum laccase and class II peroxidase genes revealed the distinct evolutional origin of these genes in the Steccherinaceae family.

White-rot basidiomycetes Junghuhnia nitida and Steccherinum bourdotii: Oxidative potential and laccase properties in comparison with Trametes hirsuta and Coriolopsis caperata.

White-rot basidiomycetes from the poorly studied residual polyporoid clade of Polyporales order Junghuhnia nitida (Pers.) Ryvarden and Steccherinum bourdotii Saliba & A. David grow as secondary xylotrohps on well decomposed woody materials. The main objective of the current study was to compare oxidative potential, growth, production of oxidative enzymes and laccase properties of J. nitida and S. bourdotii with that of typical primary xylotrohps Trametes hirsuta (Wulfen) Lloyd and Coriolopsis caperata (Berk.) Murrill, belonging to the core polyporoid clade. For the first time we report species J. nitida and S. bourdotii as active laccase producers. New laccases from J. nitida and S. bourdotii were purified and characterized. They had an identical molecular weight of 63 kDa and isoelectric points of 3.4 and 3.1, respectively. However, the redox potential of the T1 copper site for both J. nitida (610 mV) and S. bourdotii (640 mV) laccases was lower than those for T. hirsuta and C. caperata laccases. The new laccases showed higher temperature optima and better thermal stability than T. hirsuta and C. caperata laccases. Their half-lives were more than 40 min at 70 °C. The laccases from J. nitida and S. bourdotii showed higher affinity to syringyl-type phenolic compounds than T. hirsuta and C. caperata laccases. The oxidative potential of studied fungi as well as the properties of their laccases are discussed in terms of the fungal life-style.

A re-evaluation of Neotropical Junghuhnia s.lat. (Polyporales, Basidiomycota) based on morphological and multigene analyses.

Junghuhnia is a genus of polypores traditionally characterised by a dimitic hyphal system with clamped generative hyphae and presence of encrusted skeletocystidia. However, recent molecular studies revealed that Junghuhnia is polyphyletic and most of the species cluster with Steccherinum, a morphologically similar genus separated only by a hydnoid hymenophore. In the Neotropics, very little is known about the evolutionary relationships of Junghuhnia s.lat. taxa and very few species have been included in molecular studies. In order to test the proper phylogenetic placement of Neotropical species of this group, morphological and molecular analyses were carried out. Specimens were collected in Brazil and used for DNA sequence analyses of the internal transcribed spacer and the large subunit of the nuclear ribosomal RNA gene, the translation elongation factor 1-α gene, and the second largest subunit of RNA polymerase II gene. Herbarium collections, including type specimens, were studied for morphological comparison and to confirm the identity of collections. The molecular data obtained revealed that the studied species are placed in three different genera. Specimens of Junghuhnia carneola represent two distinct species that group in a lineage within the phlebioid clade, separated from Junghuhnia and Steccherinum, which belong to the residual polyporoid clade. Therefore, the new genus Geesterania is proposed including two species, G. carneola comb. nov. and G. davidii sp. nov. Neotropical specimens identified as Junghuhnia nitida represent a different lineage from the European species and are described as Steccherinum neonitidum sp. nov. In addition, the new combinations Steccherinum meridionale, Steccherinum polycystidiferum and Steccherinum undigerum, as well as the new name Flaviporus tenuis, are proposed.

Elaphroporia ailaoshanensis gen. et sp. nov. in Polyporales (Basidiomycota).

A new poroid wood-inhabiting fungal genus, Elaphroporia, typified by E. ailaoshanensis sp. nov., is proposed based on a combination of morphological features and molecular evidence. The genus is characterised by an annual growth habit, resupinate basidiocarps, becoming rigid and light-weight up on drying, a monomitic hyphal system with thick-walled generative hyphae bearing both clamp connections and simple septa, slightly amyloid, CB+ and ellipsoid, hyaline, thin-walled, smooth and IKI–, CB– basidiospores. Sequences of ITS and LSU nrRNA gene regions of the studied samples were generated, and phylogenetic analyses were performed with maximum likelihood, maximum parsimony and bayesian inference methods. The phylogenetic analysis based on molecular data of ITS+nLSU sequences showed that Elaphroporia belonged to the residual polyporoid clade and was closely related to Junghuhnia crustacea. Further investigation was obtained for more representative taxa in the Meruliaceae based on ITS+nLSU sequences, in which the result demonstrated that the genus Elaphroporia formed a monophyletic lineage with a strong support (100 % BS, 100 % BP, 1.00 BPP) and then grouped with Flaviporus and Steccherinum.

Morphological and molecular identification of a new species of Atraporiella (Polyporales, Basidiomycota) in China

A new poroid wood-inhabiting fungal species, Atraporiella yunnanensis sp. nov., is proposed based on morphological and molecular characters. The species is characterized by cream pore surface when dry, which is easy to separate from substrate and very rapidly stained dark brown to black when bruised; hyphal system monomitic with generative hyphae hyaline to pale brown, thin-walled, unbranched, interwoven; slightly allantoid basidiospores, 2.2–3 × 0.8–1.5 µm. The internal transcribed spacer (ITS) and the large subunit (LSU) regions of nuclear ribosomal RNA gene sequences of the studied samples were generated, and phylogenetic analyses were performed with maximum likelihood, maximum parsimony and bayesian inference methods. The phylogenetic analysis based on molecular data of ITS+nLSU sequences showed that Atraporiella yunnanensis belonged to the residual polyporoid clade, formed a monophyletic lineage with a strong support (100% BS, 100% BP, 1.00 BPP) and was closely related to A. neotropica, and then grouped with other related genera: Antrodiella, Pouzaroporia, Steccherinum and Xanthoporus. Both morphological and molecular characters confirmed the placement of the new species in Atraporiella.

Caudicicola gracilis (Polyporales, Basidiomycota), a New Polypore Species and Genus from Finland

A new monotypic polypore genus, Caudicicola Miettinen, Kotir. & Kulju, is described for the new species C. gracilis Kotir., Kulju & Miettinen. The species was collected in central Finland from Picea abies and Pinus sylvestris stumps, where it grew on undersides of stumps and roots. Caudicicola gracilis is characterized by very fragile basidiocarps, monomitic hyphal structure with clamps, short and wide tramal cells, smooth ellipsoid spores, basidia with long sterigmata and conidiogenous areas in the margins of the basidiocarp producing verrucose, slightly thick-walled conidia. The genus belongs to the residual polyporoid clade of the Polyporales in the vicinity of Steccherinaceae, but has no known close relatives.

Three species of wood-decaying fungi in Polyporales new to China

Three wood-decaying fungi, Ceriporiopsis lagerheimii, Sebipora aquosa, and Tyromyces xuchilensis, are newly recorded in China. The identifications were based on morphological and molecular evidence. The phylogenetic tree inferred from ITS+nLSU sequences of 49 species of Polyporales nests C. lagerheimii within the phlebioid clade, S. aquosa within the gelatoporia clade, and T. xuchilensis within the residual polyporoid clade. The three species are described and illustrated based on Chinese material.

Extensive characterization of the new genus Rickiopora (Polyporales)

Ceriporiopsis latemarginata and Antrodiella angulatopora are two Neotropical polypores that are very similar morphologically and are characterized by effused-reflexed basidiomes, large angular pores, small ellipsoid to ovoid basidiospores and a monomitic hyphal system with presence of thick-walled hyphae with infrequent clamps. In order to verify the evolutionary relations of C. latemarginata and to find its taxonomic placement, morphological, biological, and phylogenetic studies were carried out, as well as comparisons with Antrodiella s.s. and Ceriporiopsis s.s. Mono- and poly-sporic cultures were obtained and used for mating system and nuclear behaviour studies, as well as for DNA sequence analyses of the internal transcribed spacer and large subunit of ribosomal RNA gene, translation elongation factor 1-alpha gene and RNA polymerase II second largest subunit-like gene. Type specimens of C. latemarginata and A. angulatopora were morphologically examined and their synonymy was confirmed. The results obtained support the description of a new polypore genus Rickiopora in the residual polyporoid clade characterized by a bipolar mating system, an astatocoenocytic nuclear behaviour, and a monomitic hyphal system that display a metachromatic reaction in cresyl blue.

Phylogeny and taxonomy of Ceriporiopsis (Polyporales) with descriptions of two new species from southern China

Phylogenies of Ceriporiopsis and related genera were studied using DNA sequences from the ITS+28S nuclear ribosomal RNA gene regions. Two species, Ceriporiopsis alboaurantia and C. semisupina, are described as new to science. Ceriporiopsis alboaurantia is characterized by annual growth habit, resupinate basidiocarps with white pore surface when fresh, turning to apricot-orange to dark orange upon drying, monomitic hyphal system with clamped generative hyphae encrusted with pale yellow crystals, ellipsoid and thin-walled basidiospores (4–5 ´ 3–3.3 µm), and plenty of pale-yellow to pale-orange oily substances in subiculum and trama. Ceriporiopsis semisupina is distinguished by annual, effused-reflexed basidiocarps with greyish brown to reddish brown pore surface, monomitic hyphal system with clamped generative hyphae bearing crystalline incrustation, long-clavate basidia, ellipsoid and thin-walled basidiospores (4–4.5 ´ 3–3.3 µm). Like previous study, the phylogenetic analysis presented here also showed that Ceriporiopsis is not monophyletic and the sampled species were grouped in four clades, including phlebia clade, residual polyporoid clade, tyromyces clade and gelatoporia clade.

Phylogenetic and phylogenomic overview of the Polyporales

We present a phylogenetic and phylogenomic overview of the Polyporales. The newly sequenced genomes of Bjerkandera adusta, Ganoderma sp., and Phlebia brevispora are introduced and an overview of 10 currently available Polyporales genomes is provided. The new genomes are 39 500 000–49 900 00 bp and encode for 12 910–16 170 genes. We searched available genomes for single-copy genes and performed phylogenetic informativeness analyses to evaluate their potential for phylogenetic systematics of the Polyporales. Phylogenomic datasets (25, 71, 356 genes) were assembled for the 10 Polyporales species with genome data and compared with the most comprehensive dataset of Polyporales to date (six-gene dataset for 373 taxa, including taxa with missing data). Maximum likelihood and Bayesian phylogenetic analyses of genomic datasets yielded identical topologies, and the corresponding clades also were recovered in the 373-taxa dataset although with different support values in some datasets. Three previously recognized lineages of Polyporales, antrodia, core polyporoid and phlebioid clades, are supported in most datasets, while the status of the residual polyporoid clade remains uncertain and certain taxa (e.g. Gelatoporia, Grifola, Tyromyces) apparently do not belong to any of the major lineages of Polyporales. The most promising candidate single-copy genes are presented, and nodes in the Polyporales phylogeny critical for the suprageneric taxonomy of the order are identified and discussed.

Phylogenetic relationships in European Ceriporiopsis species inferred from nuclear and mitochondrial ribosomal DNA sequences

The aim of this work was to clarify taxonomy and examine evolutionary relationships within European Ceriporiopsis species using a combined analysis of the large subunit (nLSU) nuclear rRNA and small subunit (mtSSU) mitochondrial rRNA gene sequences. Data from the ITS region were applied to enhance the view of the phylogenetic relationships among different species. The studied samples grouped into four complex clades, suggesting that the genus Ceriporiopsis is polyphyletic. The generic type Ceriporiopsis gilvescens formed a separate group together with Ceriporiopsis guidella and Phlebia spp. in the phlebioid clade. In this clade, the closely related species Ceriporiopsis resinascens and Ceriporiopsis pseudogilvescens grouped together with Ceriporiopsis aneirina. C. resinascens and C. pseudogilvescens have identical LSU and SSU sequences but differ in ITS. Ceriporiopsis pannocincta also fell in the phlebioid clade, but showed closer proximity to Gloeoporus dichrous than to C. gilvescens or C. aneirina– C. pseudogilvescens– C. resinascens group. Another clade was composed of a Ceriporiopsis balaenae– Ceriporiopsis consobrina group and was found to be closely related to Antrodiella and Frantisekia, with the overall clade highly reminiscent of the residual polyporoid clade. The monotypic genus Pouzaroporia, erected in the past for Ceriporiopsis subrufa due to its remarkable morphological differences, also fell within the residual polyporoid clade. Ceriporiopsis subvermispora held an isolated position from the other species of the genus. Therefore, the previously proposed name Gelatoporia subvermispora has been adopted for this species. Physisporinus rivulosus appeared unrelated to two other European Physisporinus species. Moreover, Ceriporiopsis (= Skeletocutis) jelicii grouped in a separate clade, distinct from Ceriporiopsis species. Finally, the ITS data demonstrated the proximity of some Ceriporiopsis species ( Ceriporiopsis portcrosensis and Ceriporiopsis subsphaerospora) to Skeletocutis amorpha.