• Total Synthesis of Thuggacin cmc-A and Its Structure Determination.

      Tsutsumi, Tomohiro; Matsumoto, Moe; Iwasaki, Hitomi; Tomisawa, Kei; Komine, Keita; Fukuda, Hayato; Eustache, Jacques; Jansen, Rolf; Hatakeyama, Susumi; Ishihara, Jun; et al. (American Chemical Society, 2021-06-15)
      The first total synthesis of thuggacin cmc-A and the determination of the absolute structure are described. The thuggacin family of antibiotics is of great interest due to the antibiotic activity against Mycobacterium tuberculosis. Based on the assumption that seven stereogenic centers in thuggacin cmc-A would share the same stereochemistry as thuggacin-A, all stereogenic centers of thuggacin cmc-A were strictly constructed in a stereocontrolled manner. The total synthesis allowed its stereostructure to be fully confirmed.
    • Secondary metabolite biosynthetic diversity in the fungal family Hypoxylaceae and Xylaria hypoxylon.

      Kuhnert, E; Navarro-Muñoz, J C; Becker, K; Stadler, M; Collemare, J; Cox, R J; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (Elsevier, 2021-08-26)
      To date little is known about the genetic background that drives the production and diversification of secondary metabolites in the Hypoxylaceae. With the recent availability of high-quality genome sequences for 13 representative species and one relative (Xylaria hypoxylon) we attempted to survey the diversity of biosynthetic pathways in these organisms to investigate their true potential as secondary metabolite producers. Manual search strategies based on the accumulated knowledge on biosynthesis in fungi enabled us to identify 783 biosynthetic pathways across 14 studied species, the majority of which were arranged in biosynthetic gene clusters (BGC). The similarity of BGCs was analysed with the BiG-SCAPE engine which organised the BGCs into 375 gene cluster families (GCF). Only ten GCFs were conserved across all of these fungi indicating that speciation is accompanied by changes in secondary metabolism. From the known compounds produced by the family members some can be directly correlated with identified BGCs which is highlighted herein by the azaphilone, dihydroxynaphthalene, tropolone, cytochalasan, terrequinone, terphenyl and brasilane pathways giving insights into the evolution and diversification of those compound classes. Vice versa, products of various BGCs can be predicted through homology analysis with known pathways from other fungi as shown for the identified ergot alkaloid, trigazaphilone, curvupallide, viridicatumtoxin and swainsonine BGCs. However, the majority of BGCs had no obvious links to known products from the Hypoxylaceae or other well-studied biosynthetic pathways from fungi. These findings highlight that the number of known compounds strongly underrepresents the biosynthetic potential in these fungi and that a tremendous number of unidentified secondary metabolites is still hidden. Moreover, with increasing numbers of genomes for further Hypoxylaceae species becoming available, the likelihood of revealing new biosynthetic pathways that encode new, potentially useful compounds will significantly improve. Reaching a better understanding of the biology of these producers, and further development of genetic methods for their manipulation, will be crucial to access their treasures.
    • Fusarium: more than a node or a foot-shaped basal cell.

      Crous, P W; Lombard, L; Sandoval-Denis, M; Seifert, K A; Schroers, H-J; Chaverri, P; Gené, J; Guarro, J; Hirooka, Y; Bensch, K; et al. (Elsevier BV, 2021-08-17)
      Recent publications have argued that there are potentially serious consequences for researchers in recognising distinct genera in the terminal fusarioid clade of the family Nectriaceae. Thus, an alternate hypothesis, namely a very broad concept of the genus Fusarium was proposed. In doing so, however, a significant body of data that supports distinct genera in Nectriaceae based on morphology, biology, and phylogeny is disregarded. A DNA phylogeny based on 19 orthologous protein-coding genes was presented to support a very broad concept of Fusarium at the F1 node in Nectriaceae. Here, we demonstrate that re-analyses of this dataset show that all 19 genes support the F3 node that represents Fusarium sensu stricto as defined by F. sambucinum (sexual morph synonym Gibberella pulicaris). The backbone of the phylogeny is resolved by the concatenated alignment, but only six of the 19 genes fully support the F1 node, representing the broad circumscription of Fusarium. Furthermore, a re-analysis of the concatenated dataset revealed alternate topologies in different phylogenetic algorithms, highlighting the deep divergence and unresolved placement of various Nectriaceae lineages proposed as members of Fusarium. Species of Fusarium s. str. are characterised by Gibberella sexual morphs, asexual morphs with thin- or thick-walled macroconidia that have variously shaped apical and basal cells, and trichothecene mycotoxin production, which separates them from other fusarioid genera. Here we show that the Wollenweber concept of Fusarium presently accounts for 20 segregate genera with clear-cut synapomorphic traits, and that fusarioid macroconidia represent a character that has been gained or lost multiple times throughout Nectriaceae. Thus, the very broad circumscription of Fusarium is blurry and without apparent synapomorphies, and does not include all genera with fusarium-like macroconidia, which are spread throughout Nectriaceae (e.g., Cosmosporella, Macroconia, Microcera). In this study four new genera are introduced, along with 18 new species and 16 new combinations. These names convey information about relationships, morphology, and ecological preference that would otherwise be lost in a broader definition of Fusarium. To assist users to correctly identify fusarioid genera and species, we introduce a new online identification database, Fusarioid-ID, accessible at www.fusarium.org. The database comprises partial sequences from multiple genes commonly used to identify fusarioid taxa (act1, CaM, his3, rpb1, rpb2, tef1, tub2, ITS, and LSU). In this paper, we also present a nomenclator of names that have been introduced in Fusarium up to January 2021 as well as their current status, types, and diagnostic DNA barcode data. In this study, researchers from 46 countries, representing taxonomists, plant pathologists, medical mycologists, quarantine officials, regulatory agencies, and students, strongly support the application and use of a more precisely delimited Fusarium (= Gibberella) concept to accommodate taxa from the robust monophyletic node F3 on the basis of a well-defined and unique combination of morphological and biochemical features. This F3 node includes, among others, species of the F. fujikuroi, F. incarnatum-equiseti, F. oxysporum, and F. sambucinum species complexes, but not species of Bisifusarium [F. dimerum species complex (SC)], Cyanonectria (F. buxicola SC), Geejayessia (F. staphyleae SC), Neocosmospora (F. solani SC) or Rectifusarium (F. ventricosum SC). The present study represents the first step to generating a new online monograph of Fusarium and allied fusarioid genera (www.fusarium.org).
    • Nomenclatural issues concerning cultured yeasts and other fungi: why it is important to avoid unneeded name changes.

      Yurkov, Andrey; Alves, Artur; Bai, Feng-Yan; Boundy-Mills, Kyria; Buzzini, Pietro; Čadež, Neža; Cardinali, Gianluigi; Casaregola, Serge; Chaturvedi, Vishnu; Collin, Valérie; et al. (BMC, 2021-07-13)
      The unambiguous application of fungal names is important to communicate scientific findings. Names are critical for (clinical) diagnostics, legal compliance, and regulatory controls, such as biosafety, food security, quarantine regulations, and industrial applications. Consequently, the stability of the taxonomic system and the traceability of nomenclatural changes is crucial for a broad range of users and taxonomists. The unambiguous application of names is assured by the preservation of nomenclatural history and the physical organisms representing a name. Fungi are extremely diverse in terms of ecology, lifestyle, and methods of study. Predominantly unicellular fungi known as yeasts are usually investigated as living cultures. Methods to characterize yeasts include physiological (growth) tests and experiments to induce a sexual morph; both methods require viable cultures. Thus, the preservation and availability of viable reference cultures are important, and cultures representing reference material are cited in species descriptions. Historical surveys revealed drawbacks and inconsistencies between past practices and modern requirements as stated in the International Code of Nomenclature for Algae, Fungi, and Plants (ICNafp). Improper typification of yeasts is a common problem, resulting in a large number invalid yeast species names. With this opinion letter, we address the problem that culturable microorganisms, notably some fungi and algae, require specific provisions under the ICNafp. We use yeasts as a prominent example of fungi known from cultures. But viable type material is important not only for yeasts, but also for other cultivable Fungi that are characterized by particular morphological structures (a specific type of spores), growth properties, and secondary metabolites. We summarize potential proposals which, in our opinion, will improve the stability of fungal names, in particular by protecting those names for which the reference material can be traced back to the original isolate.
    • Occasional comment: Fungal identification to species-level can be challenging.

      Raja, Huzefa A; Oberlies, Nicholas H; Stadler, Marc; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (Elsevier, 2021-07-14)
      [No abstract available]
    • Litoralimycins A and B, New Cytotoxic Thiopeptides from Streptomonospora sp. M2.

      Khodamoradi, Shadi; Stadler, Marc; Wink, Joachim; Surup, Frank; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (MDPI, 2020-05-26)
      Streptomonospora sp. M2 has been isolated from a soil sample collected at the Wadden Sea beach in our ongoing program aimed at the isolation of rare Actinobacteria, ultimately targeting the discovery of new antibiotics. Because crude extracts derived from cultures of this strain showed inhibitory activity against the indicator organism Bacillus subtilis, it was selected for further analysis. HPLC-MS analysis of its culture broth revealed the presence of lipophilic metabolites. The two major metabolites of those were isolated by preparative reversed-phase HPLC and preparative TLC. Their planar structures were elucidated using high-resolution electrospray ionization mass spectrometry (HRESIMS), 1D and 2D NMR data as new thiopeptide antibiotics and named litoralimycin A (1) and B (2). Although rotating frame nuclear Overhauser effect spectroscopy (ROESY) data established a Z configuration of the Δ21,26 double bond, the stereochemistry of C-5 and C-15 were assigned as S by Marfey's method after ozonolysis. The biological activity spectrum of 1 and 2 is highly uncommon for thiopeptide antibiotics, since they showed only insignificant antibacterial activity, but 1 showed strong cytotoxic effects.
    • Comparative analyses of the Hymenoscyphus fraxineus and Hymenoscyphus albidus genomes reveals potentially adaptive differences in secondary metabolite and transposable element repertoires.

      Elfstrand, Malin; Chen, Jun; Cleary, Michelle; Halecker, Sandra; Ihrmark, Katarina; Karlsson, Magnus; Davydenko, Kateryna; Stenlid, Jan; Stadler, Marc; Durling, Mikael Brandström; et al. (BMC, 2021-07-04)
      Background: The dieback epidemic decimating common ash (Fraxinus excelsior) in Europe is caused by the invasive fungus Hymenoscyphus fraxineus. In this study we analyzed the genomes of H. fraxineus and H. albidus, its native but, now essentially displaced, non-pathogenic sister species, and compared them with several other members of Helotiales. The focus of the analyses was to identify signals in the genome that may explain the rapid establishment of H. fraxineus and displacement of H. albidus. Results: The genomes of H. fraxineus and H. albidus showed a high level of synteny and identity. The assembly of H. fraxineus is 13 Mb longer than that of H. albidus', most of this difference can be attributed to higher dispersed repeat content (i.e. transposable elements [TEs]) in H. fraxineus. In general, TE families in H. fraxineus showed more signals of repeat-induced point mutations (RIP) than in H. albidus, especially in Long-terminal repeat (LTR)/Copia and LTR/Gypsy elements. Comparing gene family expansions and 1:1 orthologs, relatively few genes show signs of positive selection between species. However, several of those did appeared to be associated with secondary metabolite genes families, including gene families containing two of the genes in the H. fraxineus-specific, hymenosetin biosynthetic gene cluster (BGC). Conclusion: The genomes of H. fraxineus and H. albidus show a high degree of synteny, and are rich in both TEs and BGCs, but the genomic signatures also indicated that H. albidus may be less well equipped to adapt and maintain its ecological niche in a rapidly changing environment.
    • Meroterpenoids: A Comprehensive Update Insight on Structural Diversity and Biology.

      Nazir, Mamona; Saleem, Muhammad; Tousif, Muhammad Imran; Anwar, Muhammad Aijaz; Surup, Frank; Ali, Iftikhar; Wang, Daijie; Mamadalieva, Nilufar Z; Alshammari, Elham; Ashour, Mohamed L; et al. (MDPI, 2021-06-29)
      Meroterpenoids are secondary metabolites formed due to mixed biosynthetic pathways which are produced in part from a terpenoid co-substrate. These mixed biosynthetically hybrid compounds are widely produced by bacteria, algae, plants, and animals. Notably amazing chemical diversity is generated among meroterpenoids via a combination of terpenoid scaffolds with polyketides, alkaloids, phenols, and amino acids. This review deals with the isolation, chemical diversity, and biological effects of 452 new meroterpenoids reported from natural sources from January 2016 to December 2020. Most of the meroterpenoids possess antimicrobial, cytotoxic, antioxidant, anti-inflammatory, antiviral, enzyme inhibitory, and immunosupressive effects.
    • Discovery of novel biologically active secondary metabolites from Thai mycodiversity with anti-infective potential

      Kuephadungphan, Wilawan; Macabeo, Allan Patrick G.; Luangsa-Ard, Janet Jennifer; Stadler, Marc; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (Elsevier, 2021-01-01)
      This mini-review is dedicated to the summary of results of the EU-funded Project “Golden Mycological Triangle” (acronym GoMyTri), which was carried out in collaboration of three research infrastructures in Germany, the Netherlands and Thailand during the years 2014–2018. The cooperation explored the mycological and microbiological biodiversity of Europe and Southeast Asia with regard to the search for the badly needed new antibiotics and other biologically active secondary metabolites. The project was conducted to foster international collaboration networks, know-how exchange and interdisciplinary training of young scientists. The first two years of the project were mainly dedicated to field work, and several hundreds of fungal cultures have been isolated from material mostly collected in Thailand. These fungal strains were characterized by morphological and molecular phylogenetic methods and several new taxa were discovered. The cultures underwent screening for antimicrobial and nematicidal metabolites and a number of bioactive metabolites have already been found, isolated and characterized. Several large phylogenetic studies have already been published that resulted from the project work. The results were also brought to the attention of the scientific community as well as the general public through various dissemination events. Based on the tremendous success of this project, a follow-up project application including additional partners from Africa and further European countries has recently been filed and approved, and the international, interdisciplinary collaboration will now continue in the new RISE-MSCA-Project (acronym “Mycobiomics”).
    • Analogs of the carotane antibiotic fulvoferruginin from submerged cultures of a Thai sp.

      Sandargo, Birthe; Kaysan, Leon; Teponno, Rémy B; Richter, Christian; Thongbai, Benjarong; Surup, Frank; Stadler, Marc; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (Beilstein Institut, 2021-06-04)
      A recent find of a Marasmius species in Northern Thailand led to the isolation of five unprecedented derivatives of the carotane antibiotic fulvoferruginin (1), fulvoferruginins B-F (2-6). The structures of these sesquiterpenoids were elucidated using HRESIMS, 1D and 2D NMR, as well as CD spectroscopy. Assessing the bioactivity, fulvoferruginin emerged as a potent cytotoxic agent of potential pharmaceutical interest.
    • Synthesis of the fungal macrolide berkeleylactone A and its inhibition of microbial biofilm formation.

      Schriefer, Manuel G; Schrey, Hedda; Zeng, Haoxuan; Stadler, Marc; Schobert, Rainer; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (Royal Society of Chemistry, 2021-05-03)
      The fungal macrolide berkeleylactone A was synthesised in 13 steps and 24% yield using (R)-propylene oxide and an asymmetric Noyori hydrogenation of a β-ketoester to install the stereogenic centres. A domino addition-Wittig olefination of a 13-hydroxytetradecanal intermediate with the cumulated ylide Ph3PCCO closed the macrocyle by establishing the α,β-unsaturated ester group, necessary for the attachment of the sidechain thiol via a thia-Michael reaction. The synthetic berkeleylactone A inhibited the formation of Staphylococcus aureus biofilms and showed significant dispersive effects on preformed biofilms of Candida albicans by at least 45% relative to untreated controls at concentrations as low as 1.3 μg mL-1.
    • How to publish a new fungal species, or name, version 3.0.

      Aime, M Catherine; Miller, Andrew N; Aoki, Takayuki; Bensch, Konstanze; Cai, Lei; Crous, Pedro W; Hawksworth, David L; Hyde, Kevin D; Kirk, Paul M; Lücking, Robert; et al. (BMC, 2021-05-03)
      It is now a decade since The International Commission on the Taxonomy of Fungi (ICTF) produced an overview of requirements and best practices for describing a new fungal species. In the meantime the International Code of Nomenclature for algae, fungi, and plants (ICNafp) has changed from its former name (the International Code of Botanical Nomenclature) and introduced new formal requirements for valid publication of species scientific names, including the separation of provisions specific to Fungi and organisms treated as fungi in a new Chapter F. Equally transformative have been changes in the data collection, data dissemination, and analytical tools available to mycologists. This paper provides an updated and expanded discussion of current publication requirements along with best practices for the description of new fungal species and publication of new names and for improving accessibility of their associated metadata that have developed over the last 10 years. Additionally, we provide: (1) model papers for different fungal groups and circumstances; (2) a checklist to simplify meeting (i) the requirements of the ICNafp to ensure the effective, valid and legitimate publication of names of new taxa, and (ii) minimally accepted standards for description; and, (3) templates for preparing standardized species descriptions.
    • Ophiocordyceps flavida sp. nov. (Ophiocordycipitaceae), a new species from Thailand associated with Pseudogibellula formicarum (Cordycipitaceae), and their bioactive secondary metabolites

      Mongkolsamrit, Suchada; Noisripoom, Wasana; Pumiputikul, Siraphop; Boonlarppradab, Chollaratt; Samson, Robert A.; Stadler, Marc; Becker, Kevin; Luangsa-Ard, Janet Jennifer; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (Springer Nature, 2021-04-01)
      During a diversity study of entomopathogenic fungi in an agricultural ecosystem, two fungi were collected, isolated, and identified based on molecular phylogenetic analyses of three nuclear loci (LSU, TEF1, and RPB1) combined with morphological data. In this study, one novel species is described, Ophiocordyceps flavida, and a new record of Pseudogibellula formicarum for Thailand. Ophiocordyceps flavida morphologically resembles the Hirsutella anamorph of Ophiocordyceps pruinosa by having a mononematous character of the conidiophores and the same insect host (Hemiptera: Cicadellidae). Pseudogibellula formicarum is found to occur simultaneously with O. flavida, producing white conidiophores on the host. Additionally, secondary metabolites of both fungi were investigated and the major compound in O. flavida was identified as 2-[2-(4-chlorophenyl)ethyl]-2-(1,1-dimethylethyl)-oxirane. Pseudogibellula formicarum from Ghana and Thailand produces 6-methoxy-1H-indole-3-carbonitrile as a main component. These compounds are known from chemical synthesis or as products of biotransformation, respectively. However, they were obtained in our study as genuine fungal metabolites for the first time and may even constitute chemotaxonomic markers for the respective species
    • Macrooxazoles A-D, New 2,5-Disubstituted Oxazole-4-Carboxylic Acid Derivatives from the Plant Pathogenic Fungus .

      Matio Kemkuignou, Blondelle; Treiber, Laura; Zeng, Haoxuan; Schrey, Hedda; Schobert, Rainer; Stadler, Marc; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (MDPI, 2020-11-24)
      In our ongoing search for new bioactive fungal metabolites, four previously undescribed oxazole carboxylic acid derivatives (1-4) for which we proposed the trivial names macrooxazoles A-D together with two known tetramic acids (5-6) were isolated from the plant pathogenic fungus Phoma macrostoma. Their structures were elucidated based on high-resolution mass spectrometry (HR-MS) and nuclear magnetic resonance (NMR) spectroscopy. The hitherto unclear structure of macrocidin Z (6) was also confirmed by its first total synthesis. The isolated compounds were evaluated for their antimicrobial activities against a panel of bacteria and fungi. Cytotoxic and anti-biofilm activities of the isolates are also reported herein. The new compound 3 exhibited weak-to-moderate antimicrobial activity as well as the known macrocidins 5 and 6. Only the mixture of compounds 2 and 4 (ratio 1:2) showed weak cytotoxic activity against the tested cancer cell lines with an IC50 of 23 µg/mL. Moreover, the new compounds 2 and 3, as well as the known compounds 5 and 6, interfered with the biofilm formation of Staphylococcus aureus, inhibiting 65%, 75%, 79%, and 76% of biofilm at 250 µg/mL, respectively. Compounds 5 and 6 also exhibited moderate activity against S. aureus preformed biofilm with the highest inhibition percentage of 75% and 73% at 250 µg/mL, respectively.
    • Diketopiperazines from Batnamyces globulariicola, gen. & sp. nov. (Chaetomiaceae), a fungus associated with roots of the medicinal plant Globularia alypum in Algeria

      Noumeur, Sara R.; Teponno, Rémy B.; Helaly, Soleiman E.; Wang, Xue Wei; Harzallah, Daoud; Houbraken, Jos; Crous, Pedro W.; Stadler, Marc; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (Springer, 2020-06-01)
      Eight diketopiperazines including five previously unreported derivatives were isolated from an endophytic fungus cultured from the medicinal plant Globularia alypum collected in Algeria. The strain was characterised by means of morphological studies and molecular phylogenetic methods and was found to represent a species of a new genus in the Chaetomiaceae, for which we propose the name Batnamyces globulariicola. The taxonomic position of the new genus, which appears phylogenetically related to Stolonocarpus and Madurella, was evaluated by a multi-locus genealogy and by morphological studies in comparison to DNA sequence data reported in the recent monographs of the family. The culture remained sterile on several culture media despite repeated attempts to induce sporulation, and only some chlamydospores were formed. After fermentation in submerged culture and extraction of the cultures with organic solvents, the major secondary metabolites of B. globulariicola were isolated and their chemical structures were elucidated by extensive spectral analysis including nuclear magnetic resonance (NMR) spectroscopy, high-resolution electrospray ionisation mass spectrometry (HRESIMS), and electronic circular dichroism (ECD) measurements. The isolated compounds were tested for their biological activities against various bacteria, fungi, and two mammalian cell lines, but only three of them exhibited weak cytotoxicity against KB3.1 cells, but no antimicrobial effects were observed.
    • New developments in mycological taxonomy and nomenclature and news about the future development of Mycological Progress.

      Stadler, Marc; Weber, Evi; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (Springer Nature, 2021-03-27)
      [No abstract available]
    • Multi-locus phylogeny of the genus Curvularia and description of ten new species

      Marin-Felix, Y.; Hernández-Restrepo, M.; Crous, P. W.; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (Springer Nature, 2020-06-01)
      Curvularia is a cosmopolitan genus that includes species associated with plants, animals and humans, several of which are of clinical significance. Some of these species are important pathogens of grasses, causing devastating diseases on cereal crops in the family Poaceae. In the present multi-locus study, ex-type and reference strains of Curvularia, as well as several strains deposited in the CBS culture collection of the Westerdijk Fungal Biodiversity Institute, were included. Based on ITS, GAPDH and TEF1 sequences, as well as phenotypic data, ten new species are described and illustrated: C. arcana, C. austriaca, C. canadensis, C. ellisii, C. pseudoclavata, C. pseudoellisii, C. pseudointermedia, C. pseudoprotuberata, C. siddiquii and C. tribuli. Moreover, the new combinations C. cactivora and C. patereae are proposed, and an epitype for C. oryzae-sativae is designated. In addition, illustrations and descriptions are provided for C. cactivora, C. ellisii, C. crassiseptata, C. neergaardii, C. oryzae, C. oryzae-sativae, C. protuberata and C. verruciformis. The description of C. pseudobrachyspora is emended, and its host and distribution records are updated.
    • Secondary metabolites of Phlebopus species from Northern Thailand

      Chuankid, Boontiya; Schrey, Hedda; Thongbai, Benjarong; Raspé, Olivier; Arnold, Norbert; Hyde, Kevin David; Stadler, Marc; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (Springer.com, 2020-12-01)
      Submerged cultures of the edible mushrooms Phlebopus portentosus and Phlebopus spongiosus were screened for their secondary metabolites by HPLC-UV/Vis and HR-LC-ESI-MS. Two new compounds, 9′-hydroxyphenyl pulvinone (1), containing an unusual pulvinone structure, and phlebopyron (2), together with the seven known pigments, atromentic acid (3), xerocomic acid (4), variegatic acid (5), methyl atromentate (6), methyl isoxerocomate (7), methyl variegatate (8), and variegatorubin (9) were isolated from the cultures. Their structures were assigned on the basis of extensive 1D/2D NMR spectroscopic analyses, as well as HR-ESI-MS, and HR-ESI-MS/MS measurements. Furthermore, the isolated compounds were evaluated for their antimicrobial and cytotoxic properties. 9′-hydroxyphenyl pulvinone (1), xerocomic acid (4), and methyl variegatate (8) exhibited weak to moderate cytotoxic activities against several tumor cell lines. The present paper provides a comprehensive characterization of pigments from the class of pulvinic acids that are present in the basidiomes of many edible bolete species.
    • Three New Derivatives of Zopfinol from Pseudorhypophila Mangenotii gen. et comb. nov

      Harms, Karen; Milic, Andrea; Stchigel, Alberto M; Stadler, Marc; Surup, Frank; Marin-Felix, Yasmina; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (MDPI, 2021-03-03)
      Triangularia mangenotti was analyzed for the production of secondary metabolites, resulting in the isolation of known zopfinol (1) and its new derivatives zopfinol B-C (2-4), the 10-membered lactones 7-O-acetylmultiplolide A (5) and 8-O-acetylmultiplolide A (6), together with sordarin (7), sordarin B (8), and hypoxysordarin (9). The absolute configuration of 1 was elucidated by the synthesis of MPTA-esters. Compound 1 showed antimicrobial activity against the Gram-positive bacteria Bacillus subtilis and Staphylococcus aureus and the fungus Mucor hiemalis. While 4 was weakly antibacterial, 3 showed stronger antibiotic activity against the Gram-positive bacteria and weak antifungal activity against M. hiemalis and Rhodotorula glutinis. We furthermore observed the cytotoxicity of 1, 3 and 4 against the mammalian cell lines KB3.1 and L929. Moreover, the new genus Pseudorhypophila is introduced herein to accommodate Triangularia mangenotii together with several species of Zopfiella-Z. marina, Z. pilifera, and Z. submersa. These taxa formed a well-supported monophyletic clade in the recently introduced family Navicularisporaceae, located far from the type species of the respective original genera, in a phylogram based on the combined dataset sequences of the internal transcribed spacer region (ITS), the nuclear rDNA large subunit (LSU), and fragments of the ribosomal polymerase II subunit 2 (rpb2) and β-tubulin (tub2) genes. Zopfiella submersa is synonymized with P. marina due to the phylogenetic and morphological similarity. The isolation of zopfinols 1-4 and sordarins 7-9 confirms the potential of this fungal order as producers of bioactive compounds and suggests these compounds as potential chemotaxonomic markers.
    • Amycolatomycins A and B, Cyclic Hexapeptides Isolated from an amycolatopsis sp. 195334CR.

      Primahana, Gian; Risdian, Chandra; Mozef, Tjandrawati; Wink, Joachim; Surup, Frank; Stadler, Marc; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (MDPI, 2021-03-05)
      The rare actinobacterium Amycolatopsis sp. strain 195334CR was found to produce previously undescribed cyclic hexapeptides, which we named amycolatomycin A and B (1 and 2). Their planar structures were determined by high-resolution mass spectrometry as well as extensive 1D and 2D NMR spectroscopy, while the absolute stereochemistry of its amino acids were determined by Marfey's method. Moreover, 1 and 2 differ by the incorporation of l-Ile and l-allo-Ile, respectively, whose FDVA (Nα-(2,4-Dinitro-5-fluorphenyl)-L-valinamide) derivatives were separated on a C4 column. Their hallmark in common is a unique 2,6-dichloro-tryptophan amino acid unit. Amycolatomycin A (1) exhibited weak activity against Bacillus subtilis DSM 10 (minimum inhibitory concentration (MIC) = 33.4 µg/mL).