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he hydroxylation of fatty acids is an appealing reaction in synthetic chemistry, although the lack of selective catalysts hampers its industrial implementation. Here, we have engineered a highly regioselective fungal peroxygenase for the w-1 hydroxylation of fatty acids with quenched stepwise over-oxidation. One single mutation near the Phe catalytic tripod narrowed the heme cavity, promoting a dramatic shift toward sub-terminal hydroxylation with a drop in the over-oxidation activity. While crystallographic soaking experiments and molecular dynamic simulations shed light on this unique oxidation pattern, the selective biocatalyst was produced by Pichia pastoris at 0.4 g/L in a fed-batch bioreactor and used in the preparative synthesis of 1.4 g of (w-1)-hydroxytetradecanoic acid with 95% regioselectivity and 83% ee through the (S)-enantiomer.The hydroxylation of fatty acids is an appealing reaction in synthetic chemistry, although the lack of selective catalysts hampers its industrial implementation. Here, we have engineered a highly regioselective fungal peroxygenase for the w-1 hydroxylation of fatty acids with quenched stepwise over-oxidation. One single mutation near the Phe catalytic tripod narrowed the heme cavity, promoting a dramatic shift toward sub-terminal hydroxylation with a drop in the over-oxidation activity. While crystallographic soaking experiments and molecular dynamic simulations shed light on this unique oxidation pattern, the selective biocatalyst was produced by Pichia pastoris at 0.4 g/L in a fed-batch bioreactor and used in the preparative synthesis of 1.4 g of (w-1)-hydroxytetradecanoic acid with 95% regioselectivity and 83% ee through the (S)-enantiomer.

Terminal alkenes are among the most attractive starting materials for the synthesis of epoxides, which are essential and versatile intermediate building blocks for the pharmaceutical, fla-voring, and polymer industries. Previous research on alkene epoxidation has focused on the use of several oxidizing agents and/or different enzymes, including cytochrome P450 monooxygenases, as well as microbial whole-cell catalysts that have several drawbacks. Alternatively, we explored the ability of unspecific peroxygenases (UPOs) to selectively epoxidize terminal alkenes. UPOs are attractive biocatalysts because they are robust extracellular enzymes and only require H2O2 as cosub-strate. Here, we show how several UPOs, such as those from Cyclocybe (Agrocybe) aegerita (AaeUPO), Marasmius rotula (MroUPO), Coprinopsis cinerea (rCciUPO), Humicola insolens (rHinUPO), and Daldinia caldariorum (rDcaUPO), are able to catalyze the epoxidation of long-chain terminal alkenes (from C12:1 to C20:1) after an initial optimization of several reaction parameters (cosolvent, cosub-strate, and pH). In addition to terminal epoxides, alkenols and other hydroxylated derivatives of the alkenes were formed. Although all UPOs were able to convert and epoxidize the alkenes, nota-ble differences were observed between them, with rCciUPO being responsible for the highest sub-strate turnover and MroUPO being the most selective with respect to terminal epoxidation. The potential of peroxygenases for epoxidizing long-chain terminal alkenes represents an interesting and green alternative to the existing synthesis technologies. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

The hydroxylation of fatty acids is an appealing reaction in synthetic chemistry, although the lack of selective catalysts hampers its industrial implementation. In this study, we have engineered a highly regioselective fungal peroxygenase for the ¿-1 hydroxylation of fatty acids with quenched stepwise over-oxidation. One single mutation (A77L, Fett variant) found by structural studies and saturation mutagenesis near the Phe catalytic tripod narrowed the heme cavity, promoting a dramatic shift toward subterminal hydroxylation with a drop in the over-oxidation activity as determined by GC/MS. While molecular dynamic simulations shed light on this unique oxidation pattern, the selective biocatalyst was overexpressed in Pichia pastoris at 0.4 g/L-1 operating a fed-batch bioreactor and used for the preparative synthesis of 1.4 g of (¿-1)-hydroxytetradecanoic acid with 95% regioselectivity and 83% ee for the S-enantiomer.

Eighteen short- to medium-chain monounsaturated fatty acids were screened for hydroxylation and epoxidation using eleven different peroxygenase preparations. Most of these unspecific peroxygenases (UPOs) are secreted by fungal species of the dark-spored basidiomycetous families Psathyrellaceae and Strophariaceae, two belonged to the white-spored genus Marasmius (Marasmiaceae), and one belonged to the ascomycetous family Chaetomiaceae. The fatty acids (FAs) studied were categorized into three groups based on the position of the double bond: (i) terminal unsaturated FAs (between ω and ω-1), (ii) α-β-unsaturated FAs (between C2 and C3), and (iii) β-γ-unsaturated FAs (between C3 and C4). Their chain lengths ranged from three to nine carbon atoms. FAs with a terminal double bond were significantly oxidized by only two UPOs, namely CglUPO and CraUPO (peroxygenases from Chaetomium globosum and Coprinellus radians, respectively), producing different products. FAs with internal double bonds were converted by all tested UPOs. While epoxides were observed as products in the case of α-β-unsaturated fatty acids, only CglUPO formed β-γ-epoxides from the corresponding FAs. The product pattern of the other UPOs for β-γ-unsaturated FAs was quite similar. On the other hand, the product pattern for oxidized α-β-unsaturated FAs was more variable and, in some cases, specific to a particular UPO. For example, in the reaction with trans-2-nonenoic acid, the enzymes clustered into six groups based on the formed products.

Epoxide metabolites from n-3 and n-6 polyunsaturated fatty acids arouse interest thanks to their physiological and pharmacological activities. Their chemical synthesis has significant drawbacks, and enzymes emerge as an alternative with potentially higher selectivity and greener nature. Conversion of eleven eicosanoid, docosanoid, and other n-3/n-6 fatty acids into mono-epoxides by fungal unspecific peroxygenases (UPOs) is investigated, with emphasis on the Agrocybe aegerita (AaeUPO) and Collariella virescens (rCviUPO) enzymes. GC-MS revealed the strict regioselectivity of the n-3 and n-6 reactions with AaeUPO and rCviUPO, respectively, yielding 91%-quantitative conversion into mono-epoxides at the last double bond. Then, six of these mono-epoxides were obtained at mg-scale, purified and further structurally characterized by 1H, 13C and HMBC NMR. Moreover, chiral HPLC showed that the n-3 epoxides were also formed (by AaeUPO) with total S/R enantioselectivity (ee > 99%) while the n-6 epoxides (from rCviUPO reactions) were formed in nearly racemic mixtures. The high regio- and enantioselectivity of several of these reactions unveils the synthetic utility of fungal peroxygenases in fatty acid epoxidation.

Unspecific peroxygenases (UPOs), the extracellular enzymes capable of oxygenating a potpourri of aliphatic and aromatic substrates with a peroxide as co-substrate, come out with a new reaction: carbon-chain shortening during the conversion of fatty acids with the well-known UPOs from Coprinopsis cinerea (rCciUPO) and Cyclocybe (Agrocybe) aegerita (AaeUPO). Although a pathway (Cα-oxidation) for shortening the hydrocarbon chain of saturated fatty acids has already been reported for the UPO from Marasmius rotula (MroUPO), it turned out that rCciUPO and AaeUPO shorten the chain length of both saturated and unsaturated fatty acids in a different way. Thus, the reaction sequence does not necessarily start at the Cα-carbon (adjacent to the carboxyl group), as in the case of MroUPO, but proceeds through the subterminal (ω-1 and ω-2) carbons of the chain via several oxygenations. This new type of shortening leads to the formation of a dicarboxylic fatty acid reduced in size by two carbon atoms in the first step, which can subsequently be further shortened, carbon by carbon, by the UPO Cα-oxidation mechanism.

Currently, wood boards such as Particle Board (PB) and Medium Density Fibreboard (MDF) rely on the use of fossil-based binders, mainly formaldehyde-based binders. Although there has been a great deal of investigation into potential alternatives, to date none of the biobased alternatives have performed satisfactorily on an industrial scale.

Gegenstand der vorliegenden Arbeit war die Synthese von enantiomerenreinen α-substituierten β-Hydroxyestern zu neuartigen 4,5-disubstituieren Oxazolidin-2-onen, die auch als EVANS-Auxilare bekannt sind.

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 bacteria are among the most prominent decomposing colonizers of deadwood, we anticipated frequent and diverse nematode populations to co‐occur in such ecosystems. However, knowledge about their ability to colonize this habitat is still limited. We applied DNA‐based amplicon sequencing (metabarcoding) of the 18S rRNA gene to analyze nematode communities in sapwood and heartwood of decaying logs from 13 different tree species. We identified 247 nematode ASVs (amplicon sequence variants) from 27 families. Most of these identified families represent bacterial and fungal feeders. Their composition strongly depended on tree species identity in both wood compartments. While pH and water content were the only wood properties that contributed to nematodes’ distribution, co‐occurring fungal and prokaryotic (bacteria and archaea) α‐ and β‐ diversities were significantly related to nematode communities. By exploring thirteen different tree species, which exhibit a broad range of wood characteristics, this study provides first and comprehensive insights into nematode diversity in deadwood of temperate forests and indicates connectivity to other wood‐inhabiting organisms.

[EN] 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 Candolleomyces (Psathyrella) aberdarensis (PabUPO) and their production at large scale in bioreactor. Our strategy was based on adopting secretion mutations from Agrocybe aegerita UPO mutant −PaDa-I variant− designed by directed evolution for functional expression in yeast, which belongs to the same phylogenetic family as PabUPOs –long-type UPOs− and that shares 65% sequence identity. After replacing the native signal peptides by the evolved leader sequence from PaDa-I, we constructed and screened site-directed recombination mutant libraries yielding two recombinant PabUPOs with expression levels of 5.4 and 14.1 mg/L in S. cerevisiae. These variants were subsequently transferred to P. pastoris for overproduction in fed-batch bioreactor, boosting expression levels up to 290 mg/L with the highest volumetric activity achieved to date for a recombinant peroxygenase (60,000 U/L, with veratryl alcohol as substrate). With a broad pH activity profile, ranging from 2.0 to 9.0, these highly secreted, active and stable peroxygenases are promising tools for future engineering endeavors, as well as for their direct application in different industrial and environmental settings.

Gegenstand der vorliegenden Arbeit war die Synthese von enantiomerenreinen α-substituierten β-Hydroxyestern zu neuartigen 4,5-disubstituieren Oxazolidin-2-onen, die auch als EVANS-Auxilare bekannt sind.

Fungal unspecific peroxygenases (UPOs) are efficient biocatalysts that insert oxygen atoms into nonactivated C–H bonds with high selectivity. Many oxyfunctionalization reactions catalyzed by UPOs are favored in organic solvents, a milieu in which their enzymatic activity is drastically reduced. Using as departure point the UPO secretion mutant from Agrocybe aegerita (PaDa-I variant), in the current study we have improved its activity in organic solvents by directed evolution. Mutant libraries constructed by random mutagenesis and in vivo DNA shuffling were screened in the presence of increasing concentrations of organic solvents that differed both in regard to their chemical nature and polarity. In addition, a palette of neutral mutations generated by genetic drift that improved activity in organic solvents was evaluated by site directed recombination in vivo. The final UPO variant of this evolutionary campaign carried nine mutations that enhanced its activity in the presence of 30% acetonitrile (vol/vol) up to 23-fold over PaDa-I parental type, and it was also active and stable in aqueous acetone, methanol and dimethyl sulfoxide mixtures. These mutations, which are located at the surface of the protein and in the heme channel, seemingly helped to protect UPO from harmful effects of cosolvents by modifying interactions with surrounding residues and influencing critical loops., BT/Biocatalysis

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 networks provide an opportunity to investigate this colonizer-resource relationship more in detail and aim to directly compare results between different biotic groups. The main questions were as follows. Are network structures reflecting the trophic relationship between fungal and prokaryotic colonizers and their resources? If so, do they reflect the critical role of these groups, especially that of fungi, during decomposition? We used amplicon sequencing data to analyze fungal and prokaryotic interaction networks from deadwood of 13 temperate tree species at an early to middle stage of decomposition. Several diversity- and specialization-related indices were determined and the observed network structures were related to intrinsic wood traits. We hypothesized nonrandom bipartite networks for both groups and a higher degree of specialization for fungi, as they are the key players in wood decomposition. The results reveal highly modular and specialized interaction networks for both groups of organisms, demonstrating that many fungi and prokaryotes are resource-specific colonizers. However, as the level of specialization of fungi significantly surpassed that of prokaryotes, our findings reflect the strong association between fungi and their host. Our novel approach shows that the application of bipartite interaction networks is a useful tool to explore, quantify, and compare the deadwood-colonizers relationship based on sequencing data. IMPORTANCE Deadwood is important for our forest ecosystems. It feeds and houses many organisms, e.g., fungi and prokaryotes, with many different species contributing to its decomposition and n

Fungal unspecific peroxygenases (UPOs) are efficient biocatalysts that insert oxygen atoms into nonactivated C–H bonds with high selectivity. Many oxyfunctionalization reactions catalyzed by UPOs are favored in organic solvents, a milieu in which their enzymatic activity is drastically reduced. Using as departure point the UPO secretion mutant from Agrocybe aegerita (PaDa-I variant), in the current study we have improved its activity in organic solvents by directed evolution. Mutant libraries constructed by random mutagenesis and in vivo DNA shuffling were screened in the presence of increasing concentrations of organic solvents that differed both in regard to their chemical nature and polarity. In addition, a palette of neutral mutations generated by genetic drift that improved activity in organic solvents was evaluated by site directed recombination in vivo. The final UPO variant of this evolutionary campaign carried nine mutations that enhanced its activity in the presence of 30% acetonitrile (vol/vol) up to 23-fold over PaDa-I parental type, and it was also active and stable in aqueous acetone, methanol and dimethyl sulfoxide mixtures. These mutations, which are located at the surface of the protein and in the heme channel, seemingly helped to protect UPO from harmful effects of cosolvents by modifying interactions with surrounding residues and influencing critical loops., BT/Biocatalysis

[EN] 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 Candolleomyces (Psathyrella) aberdarensis (PabUPO) and their production at large scale in bioreactor. Our strategy was based on adopting secretion mutations from Agrocybe aegerita UPO mutant −PaDa-I variant− designed by directed evolution for functional expression in yeast, which belongs to the same phylogenetic family as PabUPOs –long-type UPOs− and that shares 65% sequence identity. After replacing the native signal peptides by the evolved leader sequence from PaDa-I, we constructed and screened site-directed recombination mutant libraries yielding two recombinant PabUPOs with expression levels of 5.4 and 14.1 mg/L in S. cerevisiae. These variants were subsequently transferred to P. pastoris for overproduction in fed-batch bioreactor, boosting expression levels up to 290 mg/L with the highest volumetric activity achieved to date for a recombinant peroxygenase (60,000 U/L, with veratryl alcohol as substrate). With a broad pH activity profile, ranging from 2.0 to 9.0, these highly secreted, active and stable peroxygenases are promising tools for future engineering endeavors, as well as for their direct application in different industrial and environmental settings.

Die vorliegende Arbeit befasst sich mit der unspezifischen Peroxygenase (UPO), einer ausschließlich von Pilzen produzierten Oxidoreduktase. Die Dissertation besteht aus drei wesentlichen Teilen: 1.) Untersuchungen zum Substratspektrum zweier ausgewählter UPOs, 2.) Untersuchungen zur Inaktivierung von UPOs, und 3.) die Etablierung einer Kaskadenreaktion von UPOs und pilzlichen Oxidasen zur Oxidation von Hydroxymethylfurfural (HMF) zu 2,5-Furandicarbonsäure (FDCA). 1) Oxidation ausgewählter organischer Schadstoffe Die Mehrheit der getesteten organischen Schadstoffe (35 von 44 chemischen Verbindungen, vgl. Tabelle 6), inklusive verschiedener Xenobiotika wie chlorierte Benzole und deren Derivate, halogenierte Biphenylether, Nitroaromaten, PAK und Phthalate, wurden durch lediglich zwei UPOs (AaeUPO und MroUPO) oxidativ umgewandelt und damit aktiviert. Die von den UPOs katalysierten Reaktionen waren durch drei Substrat-Eigenschaften limitiert: 1.) sterische Hemmung, u.a. infolge einer hohen Zahl an Substituenten (z.B. Hexachlorbenzol) oder aufgrund der grundsätzliche Sperrigkeit (Größe) des Substrat-Moleküls (z.B. 6-Ring-PAK wie Benzo[g,h,i]perylen), 2.) Inaktivierung des aromatischen Ringes durch elektronenziehende Gruppen (z.B. im Nitrobenzol) und 3.) geringe Bioverfügbarkeit und Wasserlöslichkeit. Während die Verhinderung der Oxidation durch geringe Löslichkeit und sterische Hemmung bereits von Peter (2013) und Poraj-Kobielska (2013) beschrieben wurden, stellt die Limitation durch Substrat-Deaktivierung, wie im Fall des Nitrobenzols, einen neuen Befund. 2) Inaktivierung von UPOs Für alle getesteten UPOs konnte eine intrinsische Katalase-Aktivität nachgewiesen werden, wobei deren Ausmaß unter den getesteten Enzymen stark variierte. So unterschieden sich die katalytischen Effizienzen der Katalase-Aktivität von AaeUPO und rCciUPO um eine Größenordnung, während die der MroUPO sich dazwischen einordnete. Im Rahmen der Untersuchungen konnte für die AaeUPO die Bildung eines r

Die vorliegende Arbeit befasst sich mit der unspezifischen Peroxygenase (UPO), einer ausschließlich von Pilzen produzierten Oxidoreduktase. Die Dissertation besteht aus drei wesentlichen Teilen: 1.) Untersuchungen zum Substratspektrum zweier ausgewählter UPOs, 2.) Untersuchungen zur Inaktivierung von UPOs, und 3.) die Etablierung einer Kaskadenreaktion von UPOs und pilzlichen Oxidasen zur Oxidation von Hydroxymethylfurfural (HMF) zu 2,5-Furandicarbonsäure (FDCA). 1) Oxidation ausgewählter organischer Schadstoffe Die Mehrheit der getesteten organischen Schadstoffe (35 von 44 chemischen Verbindungen, vgl. Tabelle 6), inklusive verschiedener Xenobiotika wie chlorierte Benzole und deren Derivate, halogenierte Biphenylether, Nitroaromaten, PAK und Phthalate, wurden durch lediglich zwei UPOs (AaeUPO und MroUPO) oxidativ umgewandelt und damit aktiviert. Die von den UPOs katalysierten Reaktionen waren durch drei Substrat-Eigenschaften limitiert: 1.) sterische Hemmung, u.a. infolge einer hohen Zahl an Substituenten (z.B. Hexachlorbenzol) oder aufgrund der grundsätzliche Sperrigkeit (Größe) des Substrat-Moleküls (z.B. 6-Ring-PAK wie Benzo[g,h,i]perylen), 2.) Inaktivierung des aromatischen Ringes durch elektronenziehende Gruppen (z.B. im Nitrobenzol) und 3.) geringe Bioverfügbarkeit und Wasserlöslichkeit. Während die Verhinderung der Oxidation durch geringe Löslichkeit und sterische Hemmung bereits von Peter (2013) und Poraj-Kobielska (2013) beschrieben wurden, stellt die Limitation durch Substrat-Deaktivierung, wie im Fall des Nitrobenzols, einen neuen Befund. 2) Inaktivierung von UPOs Für alle getesteten UPOs konnte eine intrinsische Katalase-Aktivität nachgewiesen werden, wobei deren Ausmaß unter den getesteten Enzymen stark variierte. So unterschieden sich die katalytischen Effizienzen der Katalase-Aktivität von AaeUPO und rCciUPO um eine Größenordnung, während die der MroUPO sich dazwischen einordnete. Im Rahmen der Untersuchungen konnte für die AaeUPO die Bildung eines r

Die vorliegende Arbeit befasst sich mit der unspezifischen Peroxygenase (UPO), einer ausschließlich von Pilzen produzierten Oxidoreduktase. Die Dissertation besteht aus drei wesentlichen Teilen: 1.) Untersuchungen zum Substratspektrum zweier ausgewählter UPOs, 2.) Untersuchungen zur Inaktivierung von UPOs, und 3.) die Etablierung einer Kaskadenreaktion von UPOs und pilzlichen Oxidasen zur Oxidation von Hydroxymethylfurfural (HMF) zu 2,5-Furandicarbonsäure (FDCA). 1) Oxidation ausgewählter organischer Schadstoffe Die Mehrheit der getesteten organischen Schadstoffe (35 von 44 chemischen Verbindungen, vgl. Tabelle 6), inklusive verschiedener Xenobiotika wie chlorierte Benzole und deren Derivate, halogenierte Biphenylether, Nitroaromaten, PAK und Phthalate, wurden durch lediglich zwei UPOs (AaeUPO und MroUPO) oxidativ umgewandelt und damit aktiviert. Die von den UPOs katalysierten Reaktionen waren durch drei Substrat-Eigenschaften limitiert: 1.) sterische Hemmung, u.a. infolge einer hohen Zahl an Substituenten (z.B. Hexachlorbenzol) oder aufgrund der grundsätzliche Sperrigkeit (Größe) des Substrat-Moleküls (z.B. 6-Ring-PAK wie Benzo[g,h,i]perylen), 2.) Inaktivierung des aromatischen Ringes durch elektronenziehende Gruppen (z.B. im Nitrobenzol) und 3.) geringe Bioverfügbarkeit und Wasserlöslichkeit. Während die Verhinderung der Oxidation durch geringe Löslichkeit und sterische Hemmung bereits von Peter (2013) und Poraj-Kobielska (2013) beschrieben wurden, stellt die Limitation durch Substrat-Deaktivierung, wie im Fall des Nitrobenzols, einen neuen Befund. 2) Inaktivierung von UPOs Für alle getesteten UPOs konnte eine intrinsische Katalase-Aktivität nachgewiesen werden, wobei deren Ausmaß unter den getesteten Enzymen stark variierte. So unterschieden sich die katalytischen Effizienzen der Katalase-Aktivität von AaeUPO und rCciUPO um eine Größenordnung, während die der MroUPO sich dazwischen einordnete. Im Rahmen der Untersuchungen konnte für die AaeUPO die Bildung eines r

Epoxidation of unsaturated fatty acids by unspecific peroxygenases (UPOs) of the best-known long-UPO subfamily, including the Agrocybe aegerita (AaeUPO) and Coprinopsis cinerea enzymes, is reported here. To understand the different oxygenation patterns by members of the long-UPO and short-UPO subfamilies, the latter represented by the Marasmius rotula enzyme (MroUPO), fatty-acid diffusion into their heme pockets was simulated with the adaptive PELE software. Computational results shed light on the inability of AaeUPO to epoxidize oleic acid (C18:1), opposed to MroUPO, due to steric hindrances to harbor (with a good interaction energy) the substrate with the ¿9 C10 atom at a catalytically relevant distance (<3.5 Å) from the oxo group in simulated heme compound-I. However, effective a-linolenic acid epoxidation is anticipated because the ¿15 C16 atom would attain such a distance in AaeUPO thanks to its more terminal position. The above hypothesis was verified using an engineered MroUPO variant (I153F/S156F) with a narrowed heme access channel mimicking that of AaeUPO. Experimental oxygenation of unsaturated fatty acids by this variant thus resembles that of AaeUPO, including regioselective (from 95% to >99%) formation of cis,cis-15,16-epoxyoctadeca-9,12-dienoic acid. The nearly complete conversion of a-linolenic acid by the two enzymes was transferred to a small preparative scale, the yield of purified product was estimated, its chemical structure analyzed by NMR, and more interestingly, stereoselective production of the 15(R),16(S) enantiomer (80–83% ee) assessed by chiral HPLC. This enzymatic synthesis overcomes the unspecificity of chemical epoxidation where the reaction cannot be restricted to the formation of monoepoxides as found during m-perchlorobenzoic acid oxidation of a-linolenic acid. Moreover, the variant was able to produce the unsaturated dicarboxylic fatty acid, together with subterminal oxygenation products, during partial conversion of oleic acid. Th, This work has received funding from the Bio Based Industries Joint Undertaking under the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No 792063 (“Development and pilot production of sustainable binder systems for wood based panels”, https://susbind.eu), the CTQ2016-79138-R and BIO2017-86559-R projects of Spanish MINECO, the Secretaria d’Universitats i Recerca of Generalitat de Catalunya, and the European Social Fund (ESF2019-FI-B-00154). The authors thank Novozymes A/S for supplying rCciUPO. MM acknowledges a Catalan Government doctoral grant., Peer Reviewed, Postprint (published version)

Die vorliegende Arbeit befasst sich mit der unspezifischen Peroxygenase (UPO), einer ausschließlich von Pilzen produzierten Oxidoreduktase. Die Dissertation besteht aus drei wesentlichen Teilen: 1.) Untersuchungen zum Substratspektrum zweier ausgewählter UPOs, 2.) Untersuchungen zur Inaktivierung von UPOs, und 3.) die Etablierung einer Kaskadenreaktion von UPOs und pilzlichen Oxidasen zur Oxidation von Hydroxymethylfurfural (HMF) zu 2,5-Furandicarbonsäure (FDCA). 1) Oxidation ausgewählter organischer Schadstoffe Die Mehrheit der getesteten organischen Schadstoffe (35 von 44 chemischen Verbindungen, vgl. Tabelle 6), inklusive verschiedener Xenobiotika wie chlorierte Benzole und deren Derivate, halogenierte Biphenylether, Nitroaromaten, PAK und Phthalate, wurden durch lediglich zwei UPOs (AaeUPO und MroUPO) oxidativ umgewandelt und damit aktiviert. Die von den UPOs katalysierten Reaktionen waren durch drei Substrat-Eigenschaften limitiert: 1.) sterische Hemmung, u.a. infolge einer hohen Zahl an Substituenten (z.B. Hexachlorbenzol) oder aufgrund der grundsätzliche Sperrigkeit (Größe) des Substrat-Moleküls (z.B. 6-Ring-PAK wie Benzo[g,h,i]perylen), 2.) Inaktivierung des aromatischen Ringes durch elektronenziehende Gruppen (z.B. im Nitrobenzol) und 3.) geringe Bioverfügbarkeit und Wasserlöslichkeit. Während die Verhinderung der Oxidation durch geringe Löslichkeit und sterische Hemmung bereits von Peter (2013) und Poraj-Kobielska (2013) beschrieben wurden, stellt die Limitation durch Substrat-Deaktivierung, wie im Fall des Nitrobenzols, einen neuen Befund. 2) Inaktivierung von UPOs Für alle getesteten UPOs konnte eine intrinsische Katalase-Aktivität nachgewiesen werden, wobei deren Ausmaß unter den getesteten Enzymen stark variierte. So unterschieden sich die katalytischen Effizienzen der Katalase-Aktivität von AaeUPO und rCciUPO um eine Größenordnung, während die der MroUPO sich dazwischen einordnete. Im Rahmen der Untersuchungen konnte für die AaeUPO die Bildung eines r

Totholz ist als wichtiges Strukturelement in Waldökosystemen und von zentraler Bedeutung für deren Funktion. Es dient zahlreichen Organismen als Lebensraum oder Substrat und ist wichtiger Bestandteil des Kohlenstoff- und Nährstoffkreislaufes. Um Totholz effizient zu zersetzen, haben saprobionte Pilze aus den Phyla der Basidiomycota und Ascomycota verschiedene ökologische und physiologische Strategien entwickelt. Die bedeutendste Rolle im Totholzabbau spielen dabei Weißfäulepilze. Sie sind in der Lage, mit ihren extrazellulären oxidativen Enzymen, wie Laccasen und verschiedenen Peroxidasen, Lignin anzugreifen, chemisch zu modifizieren und abzubauen. Über den Abbauprozess im natürlichen Totholz durch lignocellulolytische Enzyme und deren dazugehörige Pilzgemeinschaft sowie über Faktoren, die zusätzlich Einfluss auf Abbauprozesse nehmen können, ist wenig bekannt. Das Ziel dieser Arbeit innerhalb des BELongDead-Projekts (als Teil der Biodiversitäts-Exploratorien) war es deshalb, den pilzlichen Abbau von Totholz in der fortgeschrittenen initialen Phase (nach ca. sechs Jahren) des Zersetzungsprozesses zu betrachten. Weiter sollte die Rolle der lignocellulolytischen Enzyme beschrieben und ihre Abhängigkeiten von verschiedenen physikalisch-chemischen Totholzvariablen aufgezeigt werden. Darüber hinaus sollte geklärt werden, welchen Einfluss die Zusammensetzung der pilzlichen Gemeinschaft auf den Totholzabbau hat und welche Arten sowie Ökotypen dominieren. Hierfür wurden natürliche Totholzstämme 13 verschiedener heimischer Baumarten (Acer sp., Betula sp., Carpinus betulus, Fagus sylvatica, Fraxinus excelsior, Larix decidua, Picea abies, Pinus sylvestris, Populus sp., Prunus avium, Pseudotsuga menziesii, Quercus sp. und Tilia sp.) im Nationalpark Hainich-Dün (Thüringen) untersucht. Zusätzlich erfolgte die getrennte Betrachtung der pilzlichen Abbauprozesse im Splint- und Kernholz. Insgesamt wurden 82 Totholzproben entnommen und darin die Aktivitäten der Lignin-modifizierenden E, Deadwood is an important structural element and particularly relevant in forest ecosystems, as it serves as habitat and substrate for numerous organisms. Furthermore, it contributes to the carbon and nutrient cycle. Saprotrophic fungi from the phyla Basidiomycota and Ascomycota have developed various ecological and physiological strategies to efficiently decompose deadwood. Particularly, white-rot fungi play a crucial role in deadwood decomposition. They are able to oxidatively attack, chemically modify and degrade lignin with their extracellular enzymes such as laccases and various peroxidases. Nevertheless, little is known about the degradation process by lignocellulolytic enzymes in natural deadwood and the responsible fungal communities as well as on abiotic factors influencing decomposition. Therefore, the goal of this thesis within the BELongDead project (part of the German Biodiversity Exploratories) has been to investigate the fungal degradation of deadwood in the advanced initial phase (after about six years) of the decay process. Furthermore, the role of lignocellulolytic enzymes was analyzed and their dependence on various physical and chemical deadwood variables was shown. In addition, the thesis aims at clarifying the influence of the composition of the fungal community on deadwood decomposition and at answering the question which fungal species and ecotypes dominate during that process. For this purpose, natural deadwood logs of 13 tree species (Acer sp., Betula sp., Carpinus betulus, Fagus sylvatica, Fraxinus excelsior, Larix decidua, Picea abies, Pinus sylvestris, Populus sp., Prunus avium, Pseudotsuga menziesii, Quercus sp sp.) were analyzed in the Hainich-Dün National Park in Thuringia (Germany). Moreover, the fungal decomposition process was separately considered with regard to sapwood and heartwood. A total of 82 deadwood samples were taken to analyze the activities of the lignin-modifying enzymes (laccase/Lac, General peroxidase/GenP, manganese

Totholz ist als wichtiges Strukturelement in Waldökosystemen und von zentraler Bedeutung für deren Funktion. Es dient zahlreichen Organismen als Lebensraum oder Substrat und ist wichtiger Bestandteil des Kohlenstoff- und Nährstoffkreislaufes. Um Totholz effizient zu zersetzen, haben saprobionte Pilze aus den Phyla der Basidiomycota und Ascomycota verschiedene ökologische und physiologische Strategien entwickelt. Die bedeutendste Rolle im Totholzabbau spielen dabei Weißfäulepilze. Sie sind in der Lage, mit ihren extrazellulären oxidativen Enzymen, wie Laccasen und verschiedenen Peroxidasen, Lignin anzugreifen, chemisch zu modifizieren und abzubauen. Über den Abbauprozess im natürlichen Totholz durch lignocellulolytische Enzyme und deren dazugehörige Pilzgemeinschaft sowie über Faktoren, die zusätzlich Einfluss auf Abbauprozesse nehmen können, ist wenig bekannt. Das Ziel dieser Arbeit innerhalb des BELongDead-Projekts (als Teil der Biodiversitäts-Exploratorien) war es deshalb, den pilzlichen Abbau von Totholz in der fortgeschrittenen initialen Phase (nach ca. sechs Jahren) des Zersetzungsprozesses zu betrachten. Weiter sollte die Rolle der lignocellulolytischen Enzyme beschrieben und ihre Abhängigkeiten von verschiedenen physikalisch-chemischen Totholzvariablen aufgezeigt werden. Darüber hinaus sollte geklärt werden, welchen Einfluss die Zusammensetzung der pilzlichen Gemeinschaft auf den Totholzabbau hat und welche Arten sowie Ökotypen dominieren. Hierfür wurden natürliche Totholzstämme 13 verschiedener heimischer Baumarten (Acer sp., Betula sp., Carpinus betulus, Fagus sylvatica, Fraxinus excelsior, Larix decidua, Picea abies, Pinus sylvestris, Populus sp., Prunus avium, Pseudotsuga menziesii, Quercus sp. und Tilia sp.) im Nationalpark Hainich-Dün (Thüringen) untersucht. Zusätzlich erfolgte die getrennte Betrachtung der pilzlichen Abbauprozesse im Splint- und Kernholz. Insgesamt wurden 82 Totholzproben entnommen und darin die Aktivitäten der Lignin-modifizierenden E, Deadwood is an important structural element and particularly relevant in forest ecosystems, as it serves as habitat and substrate for numerous organisms. Furthermore, it contributes to the carbon and nutrient cycle. Saprotrophic fungi from the phyla Basidiomycota and Ascomycota have developed various ecological and physiological strategies to efficiently decompose deadwood. Particularly, white-rot fungi play a crucial role in deadwood decomposition. They are able to oxidatively attack, chemically modify and degrade lignin with their extracellular enzymes such as laccases and various peroxidases. Nevertheless, little is known about the degradation process by lignocellulolytic enzymes in natural deadwood and the responsible fungal communities as well as on abiotic factors influencing decomposition. Therefore, the goal of this thesis within the BELongDead project (part of the German Biodiversity Exploratories) has been to investigate the fungal degradation of deadwood in the advanced initial phase (after about six years) of the decay process. Furthermore, the role of lignocellulolytic enzymes was analyzed and their dependence on various physical and chemical deadwood variables was shown. In addition, the thesis aims at clarifying the influence of the composition of the fungal community on deadwood decomposition and at answering the question which fungal species and ecotypes dominate during that process. For this purpose, natural deadwood logs of 13 tree species (Acer sp., Betula sp., Carpinus betulus, Fagus sylvatica, Fraxinus excelsior, Larix decidua, Picea abies, Pinus sylvestris, Populus sp., Prunus avium, Pseudotsuga menziesii, Quercus sp sp.) were analyzed in the Hainich-Dün National Park in Thuringia (Germany). Moreover, the fungal decomposition process was separately considered with regard to sapwood and heartwood. A total of 82 deadwood samples were taken to analyze the activities of the lignin-modifying enzymes (laccase/Lac, General peroxidase/GenP, manganese

Die vorliegende Dissertation befasst sich vor dem Hintergrund von pilzlicher Ökophysiologie und Umweltbiotechnologie mit der Isolierung, Reinigung und Charakterisierung von neuartigen Oxidoreduktasen aus kenianischen Pilzen (Eumycota). Unter Verwendung von selektiven, antibiotikahaltigen Agarmedien wurde 2016 eine Stammsammlung von 43 pilzlichen Isolaten angelegt, die Totholz, Laubstreu und Boden besiedelnde Arten umfasst und drei verschiedene kenianische Waldtypen und Biodiversitätsschwerpunkte berücksichtigt (ostafrikanische Regen-, Berg- und Küstenwälder). Die Isolate gehörten zu 21 Familien aus drei (Unter)stämmen: Basidiomycota, Ascomycota und Mucoromycotina. Unter ihnen befanden sich Weißfäulepilze und Streuzersetzer (aus den Familien Polyporaceae und Strophariceae), ein polyporaler Braunfäulepilz (Fomitopsis meliae) und zwei Vertreter der Familie Xylariaceae, die eine Moderfäule hervorrufen. Auf Grundlage morphologischer und molekularbiologischer Analysen konnte eine neue Art der Blätterpilz-Gattung Psathyrella identifiziert und als P. aberdarensis beschrieben werden. Extrazelluläre Aktivitäten von Unspezifischer Peroxygenase (UPO, EC 1.11.2.1) and DyP-Typ-Peroxidase (DyP, EC 1.11.1.19) wurden für einige der pilzlichen Isolate nachgewiesen, u.a. für P. aberdarensis (PabUPO) und den ascomycetalen Moderfäulepilz Xylaria grammica (XgrDyP). Die zugehörigen Enzymproteine wurden gereinigt und biochemisch characterisiert. Die PabUPOs werden in Form von drei verschiedenen Isoenzymen/Isoformen exprimiert und realisieren ungewöhnlich breite pH-Profile bei entsprechend hoher Enzymstabilität. Sie gehören zur Proteinfamilie der “langen” UPOs und katalysieren typische Peroxygenierungen, u.a. die Oxidation von Alkoholen, die Spaltung von Ethern, die Demethylenierung, die Oxygenierung aromatischer Ringe und – darüber hinaus – die Oxidation von Formylfurancarbonsäure zu Furandicarbonsäure (eine spezifische Reaktion, die für die Herstellung von biobasierten Polyestern aus nach, The present dissertation deals, against the background of fungal eco-physiology and environmental biotechnology, with the isolation, purification and characterization of new fungal oxidoreducatses from Kenyan fungi (Eumycota). By using selective agar media supplemented with antibiotics, a culture collection comprising 43 fungal isolates dwelling in deadwood, leaf-litter and soil was established in 2016, considering three different Kenyan forest types and biodiversity hotspots (East African rainforest, mountain and coastal forests). The isolates turned out to belong to 21 families of the (sub)phyla Basidiomycota, Ascomycota and Mucoromycotina. Among them were white-rot and litter-decomposing fungi (from the families Polyporaceae and Strophariceae), a polyporous brown-rot species (Fomitopsis meliae) and two members of the family Xylariaceae causing soft-rot. By morphological and molecular analyses, a new species of the agaric genus Psathyrella was identified and described as Psathyrella aberdarensis. Extracellular activities of unspecific peroxygenase (UPO, EC 1.11.2.1) and DyP-type peroxidase (DyP, EC 1.11.1.19) were demonstrated for a few of the fungal isolates, among them P. aberdarensis (PabUPO) and the soft-rot ascomycete Xylaria grammica (XgrDyP), respectively. The corresponding enzyme proteins were purified and characterized. PabUPOs occur in form of three different isoenzymes/isoforms realizing unusually broad pH-profiles and stabilities. They belong to the clade of ‘long’ UPOs and catalyze typical peroxygenations, i.e. alcohol oxidation, ether cleavage, demethylenation, aromatic ring oxygenation, and beyond that, the oxidation of formylfuran carboxylic acid into furandicarboxylic acid (a specific reaction in the preparation of bio-based polyesters from renewable building blocks). XgrDyP is the first wild-type DyP reported for an ascomycetous fungus and was found to oxidize peroxidase substrates such as ABTS and 2,6-DMP but also Reactive Blue 5, veratryl alcoh

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.

Die vorliegende Dissertation befasst sich vor dem Hintergrund von pilzlicher Ökophysiologie und Umweltbiotechnologie mit der Isolierung, Reinigung und Charakterisierung von neuartigen Oxidoreduktasen aus kenianischen Pilzen (Eumycota). Unter Verwendung von selektiven, antibiotikahaltigen Agarmedien wurde 2016 eine Stammsammlung von 43 pilzlichen Isolaten angelegt, die Totholz, Laubstreu und Boden besiedelnde Arten umfasst und drei verschiedene kenianische Waldtypen und Biodiversitätsschwerpunkte berücksichtigt (ostafrikanische Regen-, Berg- und Küstenwälder). Die Isolate gehörten zu 21 Familien aus drei (Unter)stämmen: Basidiomycota, Ascomycota und Mucoromycotina. Unter ihnen befanden sich Weißfäulepilze und Streuzersetzer (aus den Familien Polyporaceae und Strophariceae), ein polyporaler Braunfäulepilz (Fomitopsis meliae) und zwei Vertreter der Familie Xylariaceae, die eine Moderfäule hervorrufen. Auf Grundlage morphologischer und molekularbiologischer Analysen konnte eine neue Art der Blätterpilz-Gattung Psathyrella identifiziert und als P. aberdarensis beschrieben werden. Extrazelluläre Aktivitäten von Unspezifischer Peroxygenase (UPO, EC 1.11.2.1) and DyP-Typ-Peroxidase (DyP, EC 1.11.1.19) wurden für einige der pilzlichen Isolate nachgewiesen, u.a. für P. aberdarensis (PabUPO) und den ascomycetalen Moderfäulepilz Xylaria grammica (XgrDyP). Die zugehörigen Enzymproteine wurden gereinigt und biochemisch characterisiert. Die PabUPOs werden in Form von drei verschiedenen Isoenzymen/Isoformen exprimiert und realisieren ungewöhnlich breite pH-Profile bei entsprechend hoher Enzymstabilität. Sie gehören zur Proteinfamilie der “langen” UPOs und katalysieren typische Peroxygenierungen, u.a. die Oxidation von Alkoholen, die Spaltung von Ethern, die Demethylenierung, die Oxygenierung aromatischer Ringe und – darüber hinaus – die Oxidation von Formylfurancarbonsäure zu Furandicarbonsäure (eine spezifische Reaktion, die für die Herstellung von biobasierten Polyestern aus nach, The present dissertation deals, against the background of fungal eco-physiology and environmental biotechnology, with the isolation, purification and characterization of new fungal oxidoreducatses from Kenyan fungi (Eumycota). By using selective agar media supplemented with antibiotics, a culture collection comprising 43 fungal isolates dwelling in deadwood, leaf-litter and soil was established in 2016, considering three different Kenyan forest types and biodiversity hotspots (East African rainforest, mountain and coastal forests). The isolates turned out to belong to 21 families of the (sub)phyla Basidiomycota, Ascomycota and Mucoromycotina. Among them were white-rot and litter-decomposing fungi (from the families Polyporaceae and Strophariceae), a polyporous brown-rot species (Fomitopsis meliae) and two members of the family Xylariaceae causing soft-rot. By morphological and molecular analyses, a new species of the agaric genus Psathyrella was identified and described as Psathyrella aberdarensis. Extracellular activities of unspecific peroxygenase (UPO, EC 1.11.2.1) and DyP-type peroxidase (DyP, EC 1.11.1.19) were demonstrated for a few of the fungal isolates, among them P. aberdarensis (PabUPO) and the soft-rot ascomycete Xylaria grammica (XgrDyP), respectively. The corresponding enzyme proteins were purified and characterized. PabUPOs occur in form of three different isoenzymes/isoforms realizing unusually broad pH-profiles and stabilities. They belong to the clade of ‘long’ UPOs and catalyze typical peroxygenations, i.e. alcohol oxidation, ether cleavage, demethylenation, aromatic ring oxygenation, and beyond that, the oxidation of formylfuran carboxylic acid into furandicarboxylic acid (a specific reaction in the preparation of bio-based polyesters from renewable building blocks). XgrDyP is the first wild-type DyP reported for an ascomycetous fungus and was found to oxidize peroxidase substrates such as ABTS and 2,6-DMP but also Reactive Blue 5, veratryl alcoh

Die vorliegende Dissertation befasst sich vor dem Hintergrund von pilzlicher Ökophysiologie und Umweltbiotechnologie mit der Isolierung, Reinigung und Charakterisierung von neuartigen Oxidoreduktasen aus kenianischen Pilzen (Eumycota). Unter Verwendung von selektiven, antibiotikahaltigen Agarmedien wurde 2016 eine Stammsammlung von 43 pilzlichen Isolaten angelegt, die Totholz, Laubstreu und Boden besiedelnde Arten umfasst und drei verschiedene kenianische Waldtypen und Biodiversitätsschwerpunkte berücksichtigt (ostafrikanische Regen-, Berg- und Küstenwälder). Die Isolate gehörten zu 21 Familien aus drei (Unter)stämmen: Basidiomycota, Ascomycota und Mucoromycotina. Unter ihnen befanden sich Weißfäulepilze und Streuzersetzer (aus den Familien Polyporaceae und Strophariceae), ein polyporaler Braunfäulepilz (Fomitopsis meliae) und zwei Vertreter der Familie Xylariaceae, die eine Moderfäule hervorrufen. Auf Grundlage morphologischer und molekularbiologischer Analysen konnte eine neue Art der Blätterpilz-Gattung Psathyrella identifiziert und als P. aberdarensis beschrieben werden. Extrazelluläre Aktivitäten von Unspezifischer Peroxygenase (UPO, EC 1.11.2.1) and DyP-Typ-Peroxidase (DyP, EC 1.11.1.19) wurden für einige der pilzlichen Isolate nachgewiesen, u.a. für P. aberdarensis (PabUPO) und den ascomycetalen Moderfäulepilz Xylaria grammica (XgrDyP). Die zugehörigen Enzymproteine wurden gereinigt und biochemisch characterisiert. Die PabUPOs werden in Form von drei verschiedenen Isoenzymen/Isoformen exprimiert und realisieren ungewöhnlich breite pH-Profile bei entsprechend hoher Enzymstabilität. Sie gehören zur Proteinfamilie der “langen” UPOs und katalysieren typische Peroxygenierungen, u.a. die Oxidation von Alkoholen, die Spaltung von Ethern, die Demethylenierung, die Oxygenierung aromatischer Ringe und – darüber hinaus – die Oxidation von Formylfurancarbonsäure zu Furandicarbonsäure (eine spezifische Reaktion, die für die Herstellung von biobasierten Polyestern aus nach, The present dissertation deals, against the background of fungal eco-physiology and environmental biotechnology, with the isolation, purification and characterization of new fungal oxidoreducatses from Kenyan fungi (Eumycota). By using selective agar media supplemented with antibiotics, a culture collection comprising 43 fungal isolates dwelling in deadwood, leaf-litter and soil was established in 2016, considering three different Kenyan forest types and biodiversity hotspots (East African rainforest, mountain and coastal forests). The isolates turned out to belong to 21 families of the (sub)phyla Basidiomycota, Ascomycota and Mucoromycotina. Among them were white-rot and litter-decomposing fungi (from the families Polyporaceae and Strophariceae), a polyporous brown-rot species (Fomitopsis meliae) and two members of the family Xylariaceae causing soft-rot. By morphological and molecular analyses, a new species of the agaric genus Psathyrella was identified and described as Psathyrella aberdarensis. Extracellular activities of unspecific peroxygenase (UPO, EC 1.11.2.1) and DyP-type peroxidase (DyP, EC 1.11.1.19) were demonstrated for a few of the fungal isolates, among them P. aberdarensis (PabUPO) and the soft-rot ascomycete Xylaria grammica (XgrDyP), respectively. The corresponding enzyme proteins were purified and characterized. PabUPOs occur in form of three different isoenzymes/isoforms realizing unusually broad pH-profiles and stabilities. They belong to the clade of ‘long’ UPOs and catalyze typical peroxygenations, i.e. alcohol oxidation, ether cleavage, demethylenation, aromatic ring oxygenation, and beyond that, the oxidation of formylfuran carboxylic acid into furandicarboxylic acid (a specific reaction in the preparation of bio-based polyesters from renewable building blocks). XgrDyP is the first wild-type DyP reported for an ascomycetous fungus and was found to oxidize peroxidase substrates such as ABTS and 2,6-DMP but also Reactive Blue 5, veratryl alcoh

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.

Die vorliegende Dissertation befasst sich vor dem Hintergrund von pilzlicher Ökophysiologie und Umweltbiotechnologie mit der Isolierung, Reinigung und Charakterisierung von neuartigen Oxidoreduktasen aus kenianischen Pilzen (Eumycota). Unter Verwendung von selektiven, antibiotikahaltigen Agarmedien wurde 2016 eine Stammsammlung von 43 pilzlichen Isolaten angelegt, die Totholz, Laubstreu und Boden besiedelnde Arten umfasst und drei verschiedene kenianische Waldtypen und Biodiversitätsschwerpunkte berücksichtigt (ostafrikanische Regen-, Berg- und Küstenwälder). Die Isolate gehörten zu 21 Familien aus drei (Unter)stämmen: Basidiomycota, Ascomycota und Mucoromycotina. Unter ihnen befanden sich Weißfäulepilze und Streuzersetzer (aus den Familien Polyporaceae und Strophariceae), ein polyporaler Braunfäulepilz (Fomitopsis meliae) und zwei Vertreter der Familie Xylariaceae, die eine Moderfäule hervorrufen. Auf Grundlage morphologischer und molekularbiologischer Analysen konnte eine neue Art der Blätterpilz-Gattung Psathyrella identifiziert und als P. aberdarensis beschrieben werden. Extrazelluläre Aktivitäten von Unspezifischer Peroxygenase (UPO, EC 1.11.2.1) and DyP-Typ-Peroxidase (DyP, EC 1.11.1.19) wurden für einige der pilzlichen Isolate nachgewiesen, u.a. für P. aberdarensis (PabUPO) und den ascomycetalen Moderfäulepilz Xylaria grammica (XgrDyP). Die zugehörigen Enzymproteine wurden gereinigt und biochemisch characterisiert. Die PabUPOs werden in Form von drei verschiedenen Isoenzymen/Isoformen exprimiert und realisieren ungewöhnlich breite pH-Profile bei entsprechend hoher Enzymstabilität. Sie gehören zur Proteinfamilie der “langen” UPOs und katalysieren typische Peroxygenierungen, u.a. die Oxidation von Alkoholen, die Spaltung von Ethern, die Demethylenierung, die Oxygenierung aromatischer Ringe und – darüber hinaus – die Oxidation von Formylfurancarbonsäure zu Furandicarbonsäure (eine spezifische Reaktion, die für die Herstellung von biobasierten Polyestern aus nach, The present dissertation deals, against the background of fungal eco-physiology and environmental biotechnology, with the isolation, purification and characterization of new fungal oxidoreducatses from Kenyan fungi (Eumycota). By using selective agar media supplemented with antibiotics, a culture collection comprising 43 fungal isolates dwelling in deadwood, leaf-litter and soil was established in 2016, considering three different Kenyan forest types and biodiversity hotspots (East African rainforest, mountain and coastal forests). The isolates turned out to belong to 21 families of the (sub)phyla Basidiomycota, Ascomycota and Mucoromycotina. Among them were white-rot and litter-decomposing fungi (from the families Polyporaceae and Strophariceae), a polyporous brown-rot species (Fomitopsis meliae) and two members of the family Xylariaceae causing soft-rot. By morphological and molecular analyses, a new species of the agaric genus Psathyrella was identified and described as Psathyrella aberdarensis. Extracellular activities of unspecific peroxygenase (UPO, EC 1.11.2.1) and DyP-type peroxidase (DyP, EC 1.11.1.19) were demonstrated for a few of the fungal isolates, among them P. aberdarensis (PabUPO) and the soft-rot ascomycete Xylaria grammica (XgrDyP), respectively. The corresponding enzyme proteins were purified and characterized. PabUPOs occur in form of three different isoenzymes/isoforms realizing unusually broad pH-profiles and stabilities. They belong to the clade of ‘long’ UPOs and catalyze typical peroxygenations, i.e. alcohol oxidation, ether cleavage, demethylenation, aromatic ring oxygenation, and beyond that, the oxidation of formylfuran carboxylic acid into furandicarboxylic acid (a specific reaction in the preparation of bio-based polyesters from renewable building blocks). XgrDyP is the first wild-type DyP reported for an ascomycetous fungus and was found to oxidize peroxidase substrates such as ABTS and 2,6-DMP but also Reactive Blue 5, veratryl alcoh

The recently discovered unspecific peroxygenases (UPOs) from the ascomycetes Chaetomium globosum and Humicola insolens were capable of selectively hydroxylating isophorone to 4-hydroxyisophorone (4HIP) and 4-ketoisophorone (4KIP), which are substrates of interest for the pharmaceutical and flavor-and-fragrance sectors. The model UPO from the basidiomycete Agrocybe aegerita was less regioselective, forming 7-hydroxyisophorone (and 7-formylisophorone) in addition to 4HIP. However, it was the most stereoselective UPO yielding the S-enantiomer of 4HIP with 88% ee. Moreover, using H. insolens UPO full kinetic resolution of racemic HIP was obtained within only 15 min, with >75% recovery of the R-enantiomer. Surprisingly, the UPOs from two other basidiomycetes, Marasmius rotula and Coprinopsis cinerea, failed to transform isophorone. The different UPO selectivities were rationalized by computational simulations, in which isophorone and 4HIP were diffused into the enzymes using the adaptive PELE software, and the distances from heme-bound oxygen in H2O2-activated enzyme to different substrate atoms, and the corresponding binding energies were analyzed. Interestingly, for process upscaling, full conversion of 10 mM isophorone was achieved with H. insolens UPO within nine hours, with total turnover numbers up to 5500. These biocatalysts, which only require H2O2 for activation, may represent a novel, simple and environmentally-friendly route for the production of isophorone derivatives.

The recently discovered unspecific peroxygenases (UPOs) from the ascomycetes Chaetomium globosum and Humicola insolens were capable of selectively hydroxylating isophorone to 4-hydroxyisophorone (4HIP) and 4-ketoisophorone (4KIP), which are substrates of interest for the pharmaceutical and flavor-and-fragrance sectors. The model UPO from the basidiomycete Agrocybe aegerita was less regioselective, forming 7-hydroxyisophorone (and 7-formylisophorone) in addition to 4HIP. However, it was the most stereoselective UPO yielding the S-enantiomer of 4HIP with 88% ee. Moreover, using H. insolens UPO full kinetic resolution of racemic HIP was obtained within only 15 min, with >75% recovery of the R-enantiomer. Surprisingly, the UPOs from two other basidiomycetes, Marasmius rotula and Coprinopsis cinerea, failed to transform isophorone. The different UPO selectivities were rationalized by computational simulations, in which isophorone and 4HIP were diffused into the enzymes using the adaptive PELE software, and the distances from heme-bound oxygen in H2O2-activated enzyme to different substrate atoms, and the corresponding binding energies were analyzed. Interestingly, for process upscaling, full conversion of 10 mM isophorone was achieved with H. insolens UPO within nine hours, with total turnover numbers up to 5500. These biocatalysts, which only require H2O2 for activation, may represent a novel, simple and environmentally-friendly route for the production of isophorone derivatives., This work was supported by the EnzOx2 (H2020-BBI-PPP-2015-2-1-720297) EU-project, the AGL2014-53730-R (BIORENZYMERY) and CTQ2016-79138-R projects of the Spanish MINECO (co-financed by FEDER) and the CSIC (201740E071) project. Novozymes (Bagsvaerd, Denmark) is acknowledged for providing samples of rCciUPO and rHinUPO., Peer Reviewed, Postprint (published version)

Two unspecific peroxygenases (UPO, EC 1.11.2.1) from the basidiomycetous fungi Marasmius rotula and Marasmius wettsteinii oxidized steroids with hydroxyacetyl and hydroxyl functionalities at C17 - such as cortisone, Reichstein's substance S and prednisone - via stepwise oxygenation and final fission of the side chain. The sequential oxidation started with the hydroxylation of the terminal carbon (C21) leading to a stable geminal alcohol (e.g. cortisone 21-gem-diol) and proceeded via a second oxygenation resulting in the corresponding α-ketocarboxylic acid (e.g. cortisone 21-oic acid). The latter decomposed under formation of adrenosterone (4-androstene-3,11,17-trione) as well as formic acid and carbonic acid (that is in equilibrium with carbon dioxide); fission products comprising two carbon atoms such as glycolic acid or glyoxylic acid were not detected. Protein models based on the crystal structure data of MroUPO (Marasmius rotula unspecific peroxygenase) revealed that the bulky cortisone molecule suitably fits into the enzyme's access channel, which enables the heme iron to come in close contact to the carbons (C21, C20) of the steroidal side chain. ICP-MS analysis of purified MroUPO confirmed the presence of magnesium supposedly stabilizing the porphyrin ring system.

Composición enzimática y proceso enzimático para la producción de ácido 2,5-furanodicarboxilico a partir de 5-metoximetilfurfural usando dicha composición enzimática. En la presente invención, se hace referencia a una composición enzimática y al desarrollo de una cascada enzimática para la producción de ácido 2,5- furanodicarboxílico (FDCA) a partir de 5-metoximetilfurfural (MMF). La cascada se desencadena mediante la oxidación de MMF por aril-alcohol oxidasa, que produce H2O2 para que la peroxigenasa inespecífica lleve a cabo la escisión de un enlace éter liberando metanol, y la posterior oxigenación que conduce a la producción de FDCA. Otra enzima, metanol oxidasa, fue seleccionada para la producción in situ del H2O2 adicional requerido por la peroxigenasa inespecífica mediante la oxidación de un subproducto de la reacción. [ES], The present invention relates to an enzymatic composition and the development of an enzymatic cascade for the production of 2,5-furanodicarboxylic acid (FDCA) from 5-methoxymethylfurfural (MMF). The cascade is triggered by oxidation of MMF by aryl alcohol oxidase, which produces H2O2 so that the non-specific peroxygenase cleaves an ether bond, thereby releasing methanol, and subsequent oxygenation, which leads to the production of FDCA. Another enzyme, namely methanol oxidase, was selected for in situ production of the additional H2O2 required by the non-specific peroxidase by oxidation of a reaction byproduct. [EN]

Enzymatic oxidation of 5-hydroxymethylfurfural (HMF) and its oxidized derivatives was studied using three fungal enzymes: wild-type aryl alcohol oxidase (AAO) from three fungal species, wild-type peroxygenase from Agrocybe aegerita (AaeUPO), and recombinant galactose oxidase (GAO). The effect of pH on different reaction steps was evaluated and apparent kinetic data (Michaelis-Menten constants, turnover numbers, specific constants) were calculated for different enzyme-substrate ratios and enzyme combinations. Finally, the target product, 2,5-furandicarboxylic acid (FDCA), was prepared in a multi-enzyme cascade reaction combining three fungal oxidoreductases at micro-scale. Furthermore, an oxidase-like reaction is proposed for heme-containing peroxidases, such as UPO, horseradish peroxidase, or catalase, causing the conversion of 5-formyl-2-furancarboxylic acid into FDCA in the absence of exogenous hydrogen peroxide.

Two unspecific peroxygenases (UPO, EC 1.11.2.1) from the basidiomycetous fungi Marasmius rotula and Marasmius wettsteinii oxidized steroids with hydroxyacetyl and hydroxyl functionalities at C17 - such as cortisone, Reichstein's substance S and prednisone - via stepwise oxygenation and final fission of the side chain. The sequential oxidation started with the hydroxylation of the terminal carbon (C21) leading to a stable geminal alcohol (e.g. cortisone 21-gem-diol) and proceeded via a second oxygenation resulting in the corresponding α-ketocarboxylic acid (e.g. cortisone 21-oic acid). The latter decomposed under formation of adrenosterone (4-androstene-3,11,17-trione) as well as formic acid and carbonic acid (that is in equilibrium with carbon dioxide); fission products comprising two carbon atoms such as glycolic acid or glyoxylic acid were not detected. Protein models based on the crystal structure data of MroUPO (Marasmius rotula unspecific peroxygenase) revealed that the bulky cortisone molecule suitably fits into the enzyme's access channel, which enables the heme iron to come in close contact to the carbons (C21, C20) of the steroidal side chain. ICP-MS analysis of purified MroUPO confirmed the presence of magnesium supposedly stabilizing the porphyrin ring system.

We report here the draft genome of Kretzschmaria (Ustulina) deusta, an ascomycetous fungus that colonizes and substantially degrades hardwood and can infest living broad-leaved trees. The genome was assembled into 858 contigs, with a total size of 46.5 Mb, and 11,074 protein-coding genes were predicted.

Lecythophora (Coniochaeta) hoffmannii, a soil- and lignocellulose-inhabiting sordariomycete (Ascomycota) that can also live as a facultative tree pathogen causing soft rot, belongs to the family Coniochaetaceae. The strain CBS 245.38 sequenced here was assembled into 869 contigs, has a size of 30.8 Mb, and comprises 10,596 predicted protein-coding genes.

We report here the draft genome of Kretzschmaria (Ustulina) deusta, an ascomycetous fungus that colonizes and substantially degrades hardwood and can infest living broad-leaved trees. The genome was assembled into 858 contigs, with a total size of 46.5 Mb, and 11,074 protein-coding genes were predicted.

Propranolol is a widely used beta-blocker that is metabolized by human liver P450 monooxygenases into equipotent hydroxylated human drug metabolites (HDMs). It is paramount for the pharmaceutical industry to evaluate the toxicity and activity of these metabolites, but unfortunately, their synthesis has hitherto involved the use of severe conditions, with poor reaction yields and unwanted byproducts. Unspecific peroxygenases (UPOs) catalyze the selective oxyfunctionalization of C-H bonds, and they are of particular interest in synthetic organic chemistry. Here, we describe the engineering of UPO from Agrocybe aegerita for the efficient synthesis of 5′-hydroxypropranolol (5′-OHP). We employed a structure-guided evolution approach combined with computational analysis, with the aim of avoiding unwanted phenoxyl radical coupling without having to dope the reaction with radical scavengers. The evolved biocatalyst showed a catalytic efficiency enhanced by 2 orders of magnitude and 99% regioselectivity for the synthesis of 5′-OHP. When the UPO mutant was combined with an H2O2 in situ generation system using methanol as sacrificial electron donor, total turnover numbers of up to 264 000 were achieved, offering a cost-effective and readily scalable method to rapidly prepare 5′-OHP., BT/Biocatalysis

Lecythophora (Coniochaeta) hoffmannii, a soil- and lignocellulose-inhabiting sordariomycete (Ascomycota) that can also live as a facultative tree pathogen causing soft rot, belongs to the family Coniochaetaceae. The strain CBS 245.38 sequenced here was assembled into 869 contigs, has a size of 30.8 Mb, and comprises 10,596 predicted protein-coding genes.

Enzymatic oxidation of 5-hydroxymethylfurfural (HMF) and its oxidized derivatives was studied using three fungal enzymes: wild-type aryl alcohol oxidase (AAO) from three fungal species, wild-type peroxygenase from Agrocybe aegerita (AaeUPO), and recombinant galactose oxidase (GAO). The effect of pH on different reaction steps was evaluated and apparent kinetic data (Michaelis-Menten constants, turnover numbers, specific constants) were calculated for different enzyme-substrate ratios and enzyme combinations. Finally, the target product, 2,5-furandicarboxylic acid (FDCA), was prepared in a multi-enzyme cascade reaction combining three fungal oxidoreductases at micro-scale. Furthermore, an oxidase-like reaction is proposed for heme-containing peroxidases, such as UPO, horseradish peroxidase, or catalase, causing the conversion of 5-formyl-2-furancarboxylic acid into FDCA in the absence of exogenous hydrogen peroxide.

We report here the draft genome of Kretzschmaria (Ustulina) deusta, an ascomycetous fungus that colonizes and substantially degrades hardwood and can infest living broad-leaved trees. The genome was assembled into 858 contigs, with a total size of 46.5 Mb, and 11,074 protein-coding genes were predicted.

Background: Agrocybe aegerita is an agaricomycete fungus with typical mushroom features, which is commercially cultivated for its culinary use. In nature, it is a saprotrophic or facultative pathogenic fungus causing a white-rot of hardwood in forests of warm and mild climate. The ease of cultivation and fructification on solidified media as well as its archetypal mushroom fruit body morphology render A. aegerita a well-suited model for investigating mushroom developmental biology. Results: Here, the genome of the species is reported and analysed with respect to carbohydrate active genes and genes known to play a role during fruit body formation. In terms of fruit body development, our analyses revealed a conserved repertoire of fruiting-related genes, which corresponds well to the archetypal fruit body morphology of this mushroom. For some genes involved in fruit body formation, paralogisation was observed, but not all fruit body maturation-associated genes known from other agaricomycetes seem to be conserved in the genome sequence of A. aegerita. In terms of lytic enzymes, our analyses suggest a versatile arsenal of biopolymer-degrading enzymes that likely account for the flexible life style of this species. Regarding the amount of genes encoding CAZymes relevant for lignin degradation, A. aegerita shows more similarity to white-rot fungi than to litter decomposers, including 18 genes coding for unspecific peroxygenases and three dye-decolourising peroxidase genes expanding its lignocellulolytic machinery. Conclusions: The genome resource will be useful for developing strategies towards genetic manipulation of A. aegerita, which will subsequently allow functional genetics approaches to elucidate fundamentals of fruiting and vegetative growth including lignocellulolysis.

Propranolol is a widely used beta-blocker that is metabolized by human liver P450 monooxygenases into equipotent hydroxylated human drug metabolites (HDMs). It is paramount for the pharmaceutical industry to evaluate the toxicity and activity of these metabolites, but unfortunately, their synthesis has hitherto involved the use of severe conditions, with poor reaction yields and unwanted byproducts. Unspecific peroxygenases (UPOs) catalyze the selective oxyfunctionalization of C-H bonds, and they are of particular interest in synthetic organic chemistry. Here, we describe the engineering of UPO from Agrocybe aegerita for the efficient synthesis of 5′-hydroxypropranolol (5′-OHP). We employed a structure-guided evolution approach combined with computational analysis, with the aim of avoiding unwanted phenoxyl radical coupling without having to dope the reaction with radical scavengers. The evolved biocatalyst showed a catalytic efficiency enhanced by 2 orders of magnitude and 99% regioselectivity for the synthesis of 5′-OHP. When the UPO mutant was combined with an H2O2 in situ generation system using methanol as sacrificial electron donor, total turnover numbers of up to 264 000 were achieved, offering a cost-effective and readily scalable method to rapidly prepare 5′-OHP., BT/Biocatalysis

The present invention relates to an enzymatic composition and the development of an enzymatic cascade for the production of 2,5-furanodicarboxylic acid (FDCA) from 5-methoxymethylfurfural (MMF). The cascade is triggered by oxidation of MMF by aryl alcohol oxidase, which produces H2O2 so that the non-specific peroxygenase cleaves an ether bond, thereby releasing methanol, and subsequent oxygenation, which leads to the production of FDCA. Another enzyme, namely methanol oxidase, was selected for in situ production of the additional H2O2 required by the non-specific peroxidase by oxidation of a reaction byproduct. [EN], En la presente invención, se hace referencia a una composición enzimática y al desarrollo de una cascada enzimática para la producción de ácido 2,5- furanodicarboxílico (FDCA) a partir de 5-metoximetilfurfural (MMF). La cascada se desencadena mediante la oxidación de MMF por aril-alcohol oxidasa, que produce H 2O2 para que la peroxigenasa inespecífica lleve a cabo la escisión de un enlace éter liberando metanol, y la posterior oxigenación que conduce a la producción de FDCA. Otra enzima, metanol oxidasa, fue seleccionada para la producción in situ del H 2O2 adicional requerido por la peroxigenasa inespecífica mediante la oxidación de un subproducto de la reacción. [ES]

Composición enzimática y proceso enzimático para la producción de ácido 2,5-furanodicarboxilico a partir de 5-metoximetilfurfural usando dicha composición enzimática. En la presente invención, se hace referencia a una composición enzimática y al desarrollo de una cascada enzimática para la producción de ácido 2,5- furanodicarboxílico (FDCA) a partir de 5-metoximetilfurfural (MMF). La cascada se desencadena mediante la oxidación de MMF por aril-alcohol oxidasa, que produce H2O2 para que la peroxigenasa inespecífica lleve a cabo la escisión de un enlace éter liberando metanol, y la posterior oxigenación que conduce a la producción de FDCA. Otra enzima, metanol oxidasa, fue seleccionada para la producción in situ del H2O2 adicional requerido por la peroxigenasa inespecífica mediante la oxidación de un subproducto de la reacción. [ES], The present invention relates to an enzymatic composition and the development of an enzymatic cascade for the production of 2,5-furanodicarboxylic acid (FDCA) from 5-methoxymethylfurfural (MMF). The cascade is triggered by oxidation of MMF by aryl alcohol oxidase, which produces H2O2 so that the non-specific peroxygenase cleaves an ether bond, thereby releasing methanol, and subsequent oxygenation, which leads to the production of FDCA. Another enzyme, namely methanol oxidase, was selected for in situ production of the additional H2O2 required by the non-specific peroxidase by oxidation of a reaction byproduct. [EN]

This work gives first evidence that the unspecific peroxygenases (UPOs) from the basidiomycetes Agrocybe aegerita (AaeUPO), Coprinopsis cinerea (rCciUPO) and Marasmius rotula (MroUPO) are able to catalyze the regioselective hydroxylation of trans-stilbene to 4,4′-dihydroxy-trans-stilbene (DHS), a resveratrol (RSV) analogue whose preventive effects on cancer invasion and metastasis have very recently been shown. Nearly complete transformation of substrate (yielding DHS) was achieved with the three enzymes tested, using H2O2 as the only co-substrate, with AaeUPO showing exceptionally higher total turnover number (200000) than MroUPO (26000) and rCciUPO (1400). Kinetic studies demonstrated that AaeUPO was the most efficient enzyme catalyzing stilbene dihydroxylation with catalytic efficiencies (kcat/Km) one and two orders of magnitude higher than those of MroUPO and rCciUPO, so that 4-hydroxystilbene appears to be the best UPO substrate reported to date. In contrast, the peroxygenase from the ascomycete Chaetomium globosum (CglUPO) failed to hydroxylate trans-stilbene at the aromatic ring and instead produced the trans-epoxide in the alkenyl moiety. In addition, stilbenoids such as pinosylvin (Pin) and RSV were tested as substrates for the enzymatic synthesis of RSV from Pin and oxyresveratrol (oxyRSV) from both RSV and Pin. Overall, lower conversion rates and regioselectivities compared with trans-stilbene were accomplished by three of the UPOs, and no conversion was observed with CglUPO. The highest amount of RSV (63% of products) and oxyRSV (78%) were again attained with AaeUPO. True peroxygenase activity was demonstrated by incorporation of 18O from H218O2 into the stilbene hydroxylation products. Differences in the number of phenylalanine residues at the heme access channels seems related to differences in aromatic hydroxylation activity, since they would facilitate substrate positioning by aromatic-aromatic interactions. The only ascomycete UPO tested (that of C.

Because of their minimal requirements, substrate promiscuity and product selectivity, fungal peroxygenases are now considered to be the jewel in the crown of C–H oxyfunctionalization biocatalysts. In this work, the crystal structure of the first laboratory-evolved peroxygenase expressed by yeast was determined at a resolution of 1.5 Å. Notable differences were detected between the evolved and native peroxygenase from Agrocybe aegerita, including the presence of a full N-terminus and a broader heme access channel due to the mutations that accumulated through directed evolution. Further mutagenesis and soaking experiments with a palette of peroxygenative and peroxidative substrates suggested dynamic trafficking through the heme channel as the main driving force for the exceptional substrate promiscuity of peroxygenase. Accordingly, this study provides the first structural evidence at an atomic level regarding the mode of substrate binding for this versatile biocatalyst, which is discussed within a biological and chemical context.

Propranolol is a widely used beta-blocker that is metabolized by human liver P450 monooxygenases into equipotent hydroxylated human drug metabolites (HDMs). It is paramount for the pharmaceutical industry to evaluate the toxicity and activity of these metabolites, but unfortunately, their synthesis has hitherto involved the use of severe conditions, with poor reaction yields and unwanted byproducts. Unspecific peroxygenases (UPOs) catalyze the selective oxyfunctionalization of C–H bonds, and they are of particular interest in synthetic organic chemistry. Here, we describe the engineering of UPO from Agrocybe aegerita for the efficient synthesis of 5′-hydroxypropranolol (5′-OHP). We employed a structure-guided evolution approach combined with computational analysis, with the aim of avoiding unwanted phenoxyl radical coupling without having to dope the reaction with radical scavengers. The evolved biocatalyst showed a catalytic efficiency enhanced by 2 orders of magnitude and 99% regioselectivity for the synthesis of 5′-OHP. When the UPO mutant was combined with an H2O2 in situ generation system using methanol as sacrificial electron donor, total turnover numbers of up to 264 000 were achieved, offering a cost-effective and readily scalable method to rapidly prepare 5′-OHP.

Background 2,5-Furandicarboxylic acid is a renewable building block for the production of polyfurandicarboxylates, which are biodegradable polyesters expected to substitute their classical counterparts derived from fossil resources. It may be produced from bio-based 5-hydroxymethylfurfural or 5-methoxymethylfurfural, both obtained by the acidic dehydration of biomass-derived fructose. 5-Methoxymethylfurfural, which is produced in the presence of methanol, generates less by-products and exhibits better storage stability than 5-hydroxymethylfurfural being, therefore, the industrial substrate of choice. Results In this work, an enzymatic cascade involving three fungal oxidoreductases has been developed for the production of 2,5-furandicarboxylic acid from 5-methoxymethylfurfural. Aryl-alcohol oxidase and unspecific peroxygenase act on 5-methoxymethylfurfural and its partially oxidized derivatives yielding 2,5-furandicarboxylic acid, as well as methanol as a by-product. Methanol oxidase takes advantage of the methanol released for in situ producing H2O2 that, along with that produced by aryl-alcohol oxidase, fuels the peroxygenase reactions. In this way, the enzymatic cascade proceeds independently, with the only input of atmospheric O2, to attain a 70% conversion of initial 5-methoxymethylfurfural. The addition of some exogenous methanol to the reaction further improves the yield to attain an almost complete conversion of 5-methoxymethylfurfural into 2,5-furandicarboxylic acid. Conclusions The synergistic action of aryl-alcohol oxidase and unspecific peroxygenase in the presence of 5-methoxymethylfurfural and O2 is sufficient for the production of 2,5-furandicarboxylic acid. The addition of methanol oxidase to the enzymatic cascade increases the 2,5-furandicarboxylic acid yields by oxidizing a reaction by-product to fuel the peroxygenase reactions.

In Waldökosystemen ist Totholz von zentraler Bedeutung, indem es zahlreichen Organismen einen Lebensraum bietet oder als Substrat dient, Bestandteil des Kohlenstoff- und Nährstoffkreislaufs ist sowie als ein wichtiges strukturelles Element fungiert. Für seine Zersetzung ist die Überwindung der Ligninbarriere von besonderer Bedeutung. Dazu sind lediglich saprobionte Pilze aus den Phyla der Basidiomycota und Ascomycota in der Lage, die verschiedene Strategien – die Fäuletypen – entwickelt haben, um Lignin abzubauen oder zu modifizieren und somit Zugang zu den vom Lignin inkrustierten Polysachariden (Zellulose und Hemizellulosen) zu erhalten. Eine besondere Rolle spielen dabei Weißfäulepilze, die mit ihren extrazellulären oxidativen Enzymen, wie Laccasen und verschiedenen Peroxidasen, Lignin komplett bis zum Kohlendioxid (CO2) mineralisieren. Trotz der Bedeutung des Ligninabbaus für die Totholzzersetzung sind extrazelluläre oxidative Enzyme im natürlichen Totholz kaum erforscht. Ziel dieser Arbeit war es, die Rolle der oxidativen Enzyme für die Totholzzersetzung unter Realbedingungen zu verifizieren, ihre räumlichen und zeitlichen Muster zu beschreiben und ihre Abhängigkeiten von verschiedenen Totholzvariablen sowie der pilzlichen Artengemeinschaft in und auf Totholz zu ermitteln. Weiter wurde die Veränderung der Totholzvariablen über den Zersetzungsprozess für unterschiedliche Baumarten vergleichend beschrieben und der Einfluss der Waldbewirtschaftung auf den Prozess untersucht. Dazu wurden 197 natürliche Totholzstämme (coarse woody debris, CWD) von Fagus sylvatica (Rotbuche), Picea abies (Gemeine Fichte) und Pinus sylvestris (Gemeine Kiefer) in unterschiedlich stark bewirtschafteten Wäldern in Deutschland untersucht. Insgesamt wurden 735 Proben genommen und darin die Aktivität von Laccase (Lacc), Genereller Peroxidase (GenP) und Mangan-Peroxidase (MnP) gemessen. Weiterhin wurden Variablen wie Dichte, Wassergehalt, pH-Wert, wasserlösliche Ligninfragmente, die Gehalte, In forest ecosystems, deadwood is an important component that provides habitat and substrate for numerous organisms, contributes to the carbon and nutrient cycle as well as serves as a structural element. Overcoming the lignin barrier is a key process in deadwood degradation. Only specialized saprotrophic fungi of the phyla Basidiomycota and Ascomycota developed different strategies – the rot types – to degrade lignin or to modify it in way, which allows them to get access to the polysaccharides (cellulose and hemicelluloses) that are incrusted within the lignocellulosic complex. In this context, basidiomycetous white rot fungi secreting oxidative enzymes (especially laccases and peroxidases) are of particular importance, since they are the only organisms that are able to substantially mineralize lignin to carbon dioxide (CO2). Although lignin degradation is such an important process for deadwood degradation, oxidative enzyme activities have been only poorly studied under natural conditions in deadwood. The aim of this work was to verify the importance of oxidative enzymes for deadwood degradation in the field, to describe their temporal and spatial patterns of occurrence and to identify dependencies from deadwood variables as well as from the fungal community within and on deadwood. Furthermore, the changes of different deadwood variables were studied over the whole period of degradation and compared among three tree species. Last but not least, the influence of forest management intensity on the process of deadwood degradation was evaluated. Therefor, 197 logs of naturally occurring deadwood (coarse woody debris, CWD) of Fagus sylvatica (European beech), Picea abies (Norway spruce) and Pinus sylvestris (Scots pine) were monitored and sampled in forests with different management regimes across three regions in Germany. A total of 735 samples were taken from the logs and analyzed regarding activities of laccase (Lacc), general peroxidase (GenP) and manganese peroxid