Harald Kellner

Technische Universität Dresden - Internationales Hochschulinstitut Zittau · Umweltbiotechnologie

Background Sustainable agriculture increasingly emphasizes the importance of microbial communities in influencing plant health and productivity. In viticulture, understanding the impact of management practices on fungal communities is critical, given their role in disease dynamics, grape and wine quality. This study investigates the effects of inte...

Investigation of the secondary metabolites of the solid-state rice cultures from the European basidiomycetes Terana coerulea and Sparassis brevipes afforded three previously undescribed secondary metabolites identified as two p-terphenyl derivatives (1 and 2) and one orsellinic acid congener (3) in addition to another known, isoeverninic acid (4)....

While the succession of terrestrial plant communities is well studied, less is known about succession on dead wood, especially how it is affected by environmental factors. While temperate forests face increasing canopy mortality, which causes considerable changes in microclimates, it remains unclear how canopy openness affects fungal succession. He...

Effective conservation strategies are needed to prevent further loss of biodiversity. This requires a comprehensive assessment of species' presence, distribution, and population sizes. Such assessments can be extremely challenging for species-rich taxa, like fungi, which are difficult to detect and identify. In recent years, metabarcoding applied t...

Chemical investigation of the solid-state rice culture of the endangered European polypore Fomitiporia hartigii (Hymenochaetaceae) afforded a previously undescribed protoilludene derivative (1) in addition to six known compounds (2−7). Chemical structures of the isolated compounds were established based on HR-ESI-MS, comprehensive 1D/2D NMR spectro...

A chemical and biological exploration of the European basidiomycete Dentipellis fragilis afforded two previously undescribed natural products (1 and 2), together with three known derivatives (3-5). Chemical structures of the isolated compounds were confirmed through 1D/2D NMR spectroscopic analyses, mass spectrometry, and by comparison with the rep...

Two unprecedented isomeric secondary metabolites named vibralactones Z 5 (1a) and Z 6 (1b), in addition to eleven known compounds (2−12), were isolated from solid-state rice culture medium of Bondarzewia mesenterica (Bondarzewiaceae). Chemical structures of the isolated compounds were established via spectral analyses. The new lactone derivatives w...

Deadwood provides habitat for fungi and serves diverse ecological functions in forests. We already have profound knowledge of fungal assembly processes, physiological and enzymatic activities, and resulting physico-chemical changes during deadwood decay. However, in situ detection and identification methods, fungal origins, and a mechanistic unders...

Four previously undescribed drimane sesquiterpenoids were isolated from submerged cultures of the wood-inhabiting basidiomycete Dentipellis fragilis along with two compounds that were previously reported as synthetic or biotransformation compounds but not as natural products. The constitution and relative configuration of these compounds was determ...

Climate and land use are major determinants of biodiversity, and declines in species richness in cold and human exploited landscapes can be caused by lower rates of biotic interactions. Deadwood fungi and bacteria interact strongly with their hosts due to long‐lasting evolutionary trajectories. However, how rates of biotic interactions (specializat...

Neurodegenerative diseases are currently posing huge social, economic, and healthcare burdens among the aged populations worldwide with few and only palliative treatment alternatives available. Natural products continue to be a source of a vast array of potent neurotrophic molecules that could be considered as drug design starting points. The prese...

Enhanced nitrogen (N) deposition due to combustion of fossil fuels and agricultural fertilization is a global phenomenon which has severely altered carbon (C) and N cycling in temperate forest ecosystems in the northern hemisphere. Although deadwood holds a substantial amount of C in forest ecosystems and thus plays a crucial role in nutrient cycli...

Deadwood provides an important carbon source in forests and wooded ecosystems and, accordingly, forest management strategies discuss the enrichment of deadwood amount and diversity by different tree species. To investigate the decomposition processes of enriched deadwood, we simultaneously placed 3,669 size-standardized and gamma sterilized wood sp...

In our continued search for biologically active metabolites from cultures of rare Basidiomycota species, we found eight previously undescribed cyathane-xylosides from submerged cultures of Dentipellis fragilis, which were named dentifragilins A–H. In addition, the known cyathane deriv-atives striatal D and laxitextine A were isolated. All compounds...

The ability to catalyze diverse reactions with relevance for chemical and pharmaceutical research and industry has led to an increasing interest in fungal enzymes. There is still an enormous potential considering the sheer amount of new enzymes from the huge diversity of fungi. Most of these fungal enzymes have not been characterized yet due to the...

Lipid mediators, such as epoxidized or hydroxylated eicosanoids (EETs, HETEs) of arachidonic acid (AA), are important signaling molecules and play diverse roles at different physiological and pathophysiological levels. The EETs and HETEs formed by the cytochrome P450 enzymes are still not fully explored, but show interesting anti-inflammatory prope...

The ascomycete Truncatella angustata has a worldwide distribution. Commonly, it is associated with plants as an endophyte, pathogen, or saprotroph. The genome assembly comprises 44.9 Mbp, a G+C content of 49.2%, and 12,353 predicted genes, among them 12 unspecific peroxygenases (EC 1.11.2.1).

Forestry in Europe changed the tree species composition and reduced dead-wood amount and heterogeneity, and therefore negatively affected saproxylic diversity. Efficient conservation requires knowledge about the importance of the relevant diversity drivers across taxa. We examined the relative importance of space vs. host for saproxylic diversity a...

Fungal dye-decolorizing peroxidases (DyPs) have found applications in the treatment of dye-contaminated industrial wastes or to improve biomass digestibility. Their roles in fungal biology are uncertain, although it has been repeatedly suggested that they could participate in lignin degradation and/or modification. Using a comprehensive set of 162...

Unspecific peroxygenases (UPOs, EC 1.11.2.1) are fungal biocatalysts that have attracted considerable interest for application in chemical syntheses due to their ability to selectively incorporate peroxide-oxygen into non-activated hydrocarbons. However, the number of available and characterized UPOs is limited, as it is difficult to produce these...

Unspecific peroxygenases (UPOs) catalyze the selective transfer of single oxygen atoms from peroxides to a broad range of substrates such as un-activated hydrocarbons. Since specific oxyfunctionalizations are among the most-desired reactions in synthetic chemistry, UPOs are of high industrial interest. To broaden the number of available enzymes, co...

Unspecific peroxygenases (UPOs), whose sequences can be found in the genomes of thousands of filamentous fungi, many yeasts and certain fungus-like protists, are fascinating biocatalysts that transfer peroxide-borne oxygen (from H2O2 or R-OOH) with high efficiency to a wide range of organic substrates, including less or unactivated carbons and hete...

From the biotechnological viewpoint, the enzymatic disintegration of plant lignocellulosic biomass is a promising goal since it would deliver fermentable sugars for the chemical sector. Cellobiose dehydrogenase (CDH) is a vital component of the extracellular lignocellulose-degrading enzyme system of fungi and has a great potential to improve cataly...

Background: Fungal DyP-type peroxidases have so far been described exclusively for basidiomycetes. Moreover, peroxidases from ascomycetes that oxidize Mn2+ ions are yet not known. Methods: We describe here the physicochemical, biocatalytic, and molecular characterization of a DyP-type peroxidase (DyP, EC 1.11.1.19) from an ascomycetous fungus....

Fungal unspecific peroxygenases (UPOs) are emergent biocatalysts that perform highly selective C-H oxyfunctionalizations of organic compounds, yet their heterologous production at high levels is required for their practical use in synthetic chemistry. Here, we achieved functional expression in yeast of two new unusual acidic peroxygenases from Cand...

A bifunctional glycoside hydrolase GH78 from the ascomycete Xylaria polymorpha (XpoGH78) possesses the catalytic versatility towards both glycosides and esters, which may be advantageous for the efficient degradation of the plant cell-wall complex that contains both diverse sugar residues and esterified structures. The contribution of XpoGH78 to th...

Nematodes represent a diverse and ubiquitous group of metazoans in terrestrial environments. They feed on bacteria, fungi, plants, other nematodes or parasitize a variety of animals and hence may be considered as active members of many food webs. Deadwood is a structural component of forest ecosystems which harbors many niches for diverse biota. As...

Fungi and prokaryotes are dominant colonizers of wood and mediate its decomposition. Much progress has been achieved to unravel these communities and link them to specific wood properties. However, comparative studies considering both groups of organisms and assessing their relationships to wood resources are largely missing. Bipartite interaction...

Xylaria grammica is an ascomycetous decomposer of dead hardwood. The X. grammica strain IHIA82 was recovered from the Kakamega Forest in Kenya. The whole genome of this strain was sequenced with a total size of 47.0 Mbp, a G+C content of 48.1%, and 12,126 predicted genes.

Basidiomata of a hitherto undescribed Candolleomyces species were collected during a macrofungal foray in North Vietnam. They grew on deciduous deadwood in the Southeastern part of the Cúc Phương National Park (Vietnamese: Vườn quốc gia Cúc Phương), Ninh Bình Province. The new species Candolleomyces eurysporus, sp. nov., is characterized by broadly...

As actors of global carbon cycle, Agaricomycetes (Basidiomycota) have developed complex enzymatic machineries that allow them to decompose all plant polymers, including lignin. Among them, saprotrophic Agaricales are characterized by an unparalleled diversity of habitats and lifestyles. Comparative analysis of 52 Agaricomycetes genomes (14 of them...

As actors of global carbon cycle, Agaricomycetes (Basidiomycota) have developed complex enzymatic machineries that allow them to decompose all plant polymers, including lignin. Among them, saprotrophic Agaricales are characterized by an unparalleled diversity of habitats and lifestyles. Comparative analysis of 52 Agaricomycetes genomes (14 of them...

Cyclocybe aegerita (synonym: Agrocybe aegerita) is a widely cultivated edible and reportedly almost cosmopolitan mushroom species that serves as a model fungus for basidiome formation and as producer of useful natural products and enzymes. Focusing on strains from different continents, here, we present a phylogenetic analysis of this species and so...

Basidiocarps of a hitherto undescribed Psathyrella species were collected during a sampling excursion in North Vietnam. They grew on deciduous deadwood in the Southeastern part of the Cúc Phương National Park (Vietnamese: Vườn quốc gia Cúc Phương), Ninh Bình Province. Herein, we describe Psathyrella euryspora sp. nov. characterized by broadly ellip...

Xylaria multiplex is an ascomycete fungus that causes soft rot and is often associated with wood. Here, we report a draft genome sequence with an assembly size of 45.6 Mbp, a G+C content of 46.9%, and 10,964 predicted genes, including 617 that encode carbohydrate-active enzymes (CAZymes).

Unspecific peroxygenases (UPOs) secreted by fungi represent an intriguing enzyme type that selectively transfers peroxide-borne oxygen with high efficiency to diverse substrates including unactivated hydrocarbons. They contain a cysteine-ligated heme and catalyze hydroxylation, epoxidation, dealkylation, deacylation as well as hetero atom, halide a...

Fungal unspecific peroxygenases (UPOs, EC 1.11.2.1) form a superfamily of heme proteins and possess promiscuity for oxygen transfer reactions. The first UPO was discovered in the agaric fungus Agrocybe aegerita in 2004, and later, well-known fungal chloroperoxidase (CPO) turned out to be a phylogenetic relative (but outlier) of this enzyme type. Fu...

The saprotrophic ascomycete Xylaria hypoxylon is a widespread wood-decaying fungus on deciduous trees. Here, we report its draft genome sequence. The genome assembly has a size of 42.8 Mbp and a G+C content of 47.1% and includes 11,038 predicted genes.

Bark protects living trees against environmental influences but may promote wood decomposition by fungi and bacteria after tree death. However, the mechanisms by which bark determines the assembly process and biodiversity of decomposers remain unknown. Therefore, we partially or completely removed bark from experimentally felled trees and tested wi...

Chlorociboria aeruginascens DSM 107184 is a wood-decomposing ascomycetous fungus known to produce the bluish-green dimeric naphthoquinone derivate xylindein. Here, we present the first draft genome sequence, which contains 588 contigs with a total length of 33.1 Mb. Altogether, 8,648 protein-coding genes were predicted.

The saprotrophic soft-rot fungus Xylaria longipes was isolated from deadwood of Acer pseudoplatanus collected in the Bavarian Forest, Germany. The whole genome of this strain (DSM 107183) was sequenced with a total size of 43.2 Mb and a GC content of 48.5%. The genome comprises 12,638 predicted coding sequences.

The basidiomycete Chondrostereum purpureum (Silverleaf fungus) is a saprotroph and plant pathogen commercially used for combatting forest “weed” trees in vegetation management. However, little is known about its lignocellulose-degrading capabilities and the enzymatic machinery that is responsible for the degradative potential, and it is not yet cle...

Remapping of raw reads to the assembly. Examples are given for few full length laccase, GH6 and GH7 genes. Coverage is given on the top in blue, tracks indicate intro-exon and CDS structure and the red arrow indicates the track with the non-synonymous SNP positions. (TIF)

Gene sequences of C. purpureum classified according Gene Ontology domains: (left) biological process, (middle) molecular function and (right) cellular component. (TIF)

Assignment of gene sequences of C. purpureum to main enzyme classes according to the EC nomenclature. (TIFF)

Heat map of the secreted CAZymes of C. purpureum that show significant differences during SF in KM, SM, ASKM, ASSM, BSKM and BSSM. Differences between treatments were corroborated with Hotelling’s T2 test. Abundance is demonstrated by the normalized spectral abundance factor (% NSAF). GHs are shown in the upper side while the rest of the CAZymes (i...

Alignment of a versatile peroxidase of Pleurotus eryngii (2BOQ_A) with the class II peroxidases of C. purpureum. The three acidic amino acid residues typical for the manganese-binding sites of MnPs are indicated. (TIF)

Time course of extracellular oxidoreductase production by C. purpureum during solid-state fermentation (SSF) of cultures containing beech wood (BW, left) and beech wood supplemented with olive-mill residues ‘DOR’ (BWD, right); manganese-dependent peroxidase activities (MnP, squares), unspecific peroxygenase (UPO, circles) and laccase activities (La...

Time course of extracellular oxidoreductase production by C. purpureum during SF in cultures containing (a) Kirk medium (KM) and (b) soybean meal suspension (SM), (c) KM-ADOR (ASKM), (d) SM-ADOR (ASSM), (e) KM-birch wood (BSKM) and (f) SM-birch wood (BSSM); manganese-dependent peroxidase activities (MnP, squares), unspecific peroxygenase (UPO, circ...

Relative protein abundance (% NSAF) of enzymes produced by C. purpureum during solid-state fermentation (SSF). Beech-wood (BW, inner ring) and beech-wood plus DOR (BWD, outer ring). CAZy proteins are highlighted in bold letters. Organelle proteins include ribosomal, peroxisomal and vacuolar proteins without defined catalytic properties. Values are...

Neighbor-Joining phylogenetic tree of 67 multicopper oxidases (MCO) protein sequences (laccase (Lac), ferroxidase (FeOX), ascorbate oxidase (ASC). The sequences of C. purpureum (38 full length and 3 partial sequences (from C-terminal)) are marked by an “g” and in bold. Numbers with asterisks indicate that the proteins were found in the secretome. S...

Relative protein abundance (% NSAF) of enzymes produced by C. purpureum during (submerged) liquid fermentation (SF). (A) KM (inner ring) ASKM, (middle ring) and BSKM (outer ring) and (B) SM (inner ring), ASSM (middle ring) and BSSM (outer ring). CAZy proteins are highlighted in bold letters. Organelle proteins include ribosomal, peroxisomal and vac...

Neighbor-Joining phylogenetic tree of 54 class I and II peroxidase protein sequences (manganese, lignin, versatile and generic peroxidases (MnP, LiP, VP, GP), ascorbate peroxidases (APX) and cytochrome c peroxidases (CcP)). The sequences of C. purpureum are marked by a “g” and in bold. Numbers with asterisks indicate proteins detected in the secret...

Maximum likelihood phylogeny. Maximum Likelihood phylogeny based on 609 genes across 36 genomes. Numbers indicate bootstrap support at each node. (PDF)

Numbers of inferred duplications across all orthogroups encoding GH6 cellobiohydrolases. The middle section indicates the number of orthogroups housing genes in each of the respective classes and their copy number in each species. Agabi, Agaricus bisporus; Agrae, Agrocybe aegerita; Armce, Armillaria cepistipes; Armga, Armillaria gallica; Armme, Arm...

Lignocellulose-degrading enzymes in different basidiomycetous wood-decay fungi (modified according to Riley et al., 2014; published data from JGI & NCBI), yellow–WRF, grey–BRF, blue–unresolved wood-rot fungi. Agabi, Agaricus bisporus; Agrae, Agrocybe aegerita (Gupta et al. 2018); Armce, Armillaria cepistipes; Armga, Armillaria gallica; Armme, Armil...

Principal component analysis (PCA) bi-plot of the C. purpureum secretome from SSF cultures. (left; BW and BWD loadings are highlighted in red) and SF cultures (right; SM, ASSM, BSSM, KM, ASKM and BSKM loadings are highlighted in red) using NIPALS algorithms. (PDF)

Alignment of all full-length and partial MCO genes. The alignment was performed using ClustalW with parameters: BLOSUM cost matrix, gap opening cost = 10, gap extension cost = 0.1. (TIF)

Deadwood is an important structural component in forest ecosystems and plays a significant role in global carbon and nutrient cycling. Relatively little is known about the formation and decomposition of CWD by microbial communities in situ and about the factors controlling the associated processes. In this study, we intensively analyzed the molecul...

3D non-metric multidimensional scaling (3D-NMDS). NMDS ordination of the most abundant fungal families colonizing 13 temperate European tree species. (TIFF)

Overview of measured enzyme activities. The activities are given for samples from 13 temperate European tree species. (TIFF)

Sequences of the primers used in this study. (PDF)

Result of the goodness-of-fit-statistic (R2). The results are given for the abundant fungal families against the 3D-NMDS ordination of the fungal OTUs for all samples as well as for sapwood and heartwood. Shaded in grey: significance (uncorrected) p <0.05. (PDF)

Spearman rank correlations (p-value and Rho (ϱ)) of fungal species richness with enzyme activities and wood parameters. Comparing all samples or sapwood and heartwood separately; Significance p <0.05 (uncorrected) is indicated by grey-shading. (PDF)

Goodness-of-fit-statistic (R2). The results are given for enzyme activities and wood parameters against the 3D-NMDS ordination of the fungal OTUs for all samples as well as for sapwood and heartwood. Shaded in grey: significance (uncorrected) p <0.05. (PDF)

Spearman rank correlations. Results are given for the most abundant fungal families and ecotypes to the measured extracellular enzymes. Shaded, significance p < 0.05 (uncorrected). (PDF)

Background Heterologous gene expression is well established for various prokaryotic model systems. However, low yield, incorrect folding and instability still impede the production of soluble, bioactive proteins. To improve protein production with the Gram-positive host Bacillus subtilis, a secretory expression system was designed that enhances tra...