Sepedonium Chrysospermum Research Articles

Mycology of Hand-dug Shallow Water Wells in Awka Metropolis, Anambra State, Nigeria

Samples collected from hand-dug shallow water wells in Awka metropolis during the dry and wet seasons were subjected to mycological analysis to determine their safety for use. The fungal counts during the dry and wet seasons were 3.5x10 3 cfu/ml-8.2x10 3 cfu/ml and 5.1x10 3 cfu/ml-10.6x10 3 cfu/ml respectively. The fungi isolated during the dry and wet seasons respectively were Candida albicans (42.0% and 44.8%), Cryptococcus neoformans (9.6% and 10.2%), Rhodotorula Harrison (11.5% and 12.6%), Microsporium canis (0.0% and 0.2%), Penicillium chrysogenum (28.0% and 29.3%), Alternaria alternata (0.0% and 0.3%), Mucor mucedo (8.9% and 9.2%) and Sepedonium chrysospermum (0.0% and 0.2%). Candida albicans, Cryptococcus neoformans, Rhodotorula harrison, Penicillium chrysogenum and Mucor mucedo were isolated from 46.7%, 6.7%, 20.0%, 26.7% and 6.7% of the samples respectively during the dry season while 60.0%, 20.0%, 26.7%, 6.7%, 40.0%, 13.3%, 20.0% and 6.7% of the samples respectively had Candida albicans, Cryptococcus neoformans, Rhodotorula harrison, Microsporium canis, Penicillium chrysogenum, Alternaria alternata, Mucor mucedo and Sepedonium chrysospermum. These fungi are human pathogens which are known to cause diseases of animals and humans which if untreated may lead to fatal consequences, therefore adequate treatment of the water will safeguard the health of the users.

Keratinophilic Fungi Recovered from Feathers of Different Species of Birds in St Kitts and Nevis

The aim of the present study was to investigate the occurrence of keratinophilic fungi including dermatophytes on feathers of domestic and wild birds in the islands of St Kitts and Nevis. During 2010-2011, samples of feathers from ninety-four birds were examined by hair-baiting technique in Petri-dishes containing sterilized soil. Fungal growths appearing on the feathers and the hair-baits were microscopically examined and the cultures obtained were identified on the basis of their microscopic and colonial morphology. Chrysosporium constituted the majority (86.9%) of the 72 isolates of keratinophilic fungi, represented by mainly C tropicum and C indicum. Sepedonium spp isolates were recovered from nine of the feather samples; two of these were identified as Sepedonium chrysospermum, and the other two as S ampullosporum. Recovery of four isolates of the dermatophyte, Microsporum gypseum complex (two each of M gyspeum and M fulvum) from feathers of birds is a finding of public health significance.

A hemolytic peptide from the mycophilic fungus Sepedonium chrysospermum (Bull.) Fr.

The hemolytic activity of an extract of the mycoparasite Sepedonium chrysospermum (teleomorph Hypomyces chrysospermus) was detected and characterized. Extraction of the fungal biomass by methanol yielded a fraction in which the hemolytic activity against human red blood cells corresponded to a peptide with a molecular mass of 7,653.72Da and an isoelectric point of approximately 5.8. The peptide was temperature resistant, and the hemolysis was only partially inhibited, even after a 30-min pre-incubation at 100°C. Its hemolytic activity was unaffected by treatment with proteolytic enzymes such as trypsin. Among the divalent cations assayed, Hg(2+) was the strongest inhibitor of hemolysis. The reducing agent, dithiothreitol, and the membrane lipid, cholesterol, demonstrated concentration-dependent inhibitory activities. Finally, hemolytic activity triggered by the peptide was analyzed by scanning electron microscopy, and a pore-forming activity was detected.

Basidiomycetous Yeasts from Boletales Fruiting Bodies and Their Interactions with the Mycoparasite Sepedonium chrysospermum and the Host Fungus Paxillus

Interactions between mushrooms, yeasts, and parasitic fungi are probably common in nature, but are rarely described. Bolete fruiting bodies are associated with a broad spectrum of microorganisms including yeasts, and they are commonly infected with filamentous mycoparasites of the genus Sepedonium (teleomorph Hypomyces). We report the isolation of 17 yeast strains from Paxillus and Xerocomus, 16 of which were obtained from the surface tissue, the primary site of Sepedonium infection. Phylogenetic analyses with the D1/D2 region of the 28S ribosomal gene and the internal transcribed spacers placed the yeasts as Rhodotorula, Rhodosporidium, and Mastigobasidium from the Pucciniomycotina, Cryptococcus, Cystofilobasidium, Holtermanniella, and Trichosporon from the Agaricomycotina, and Kluyveromyces from the Saccharomycotina including the first isolation of Rhodotorula graminis from Europe. To investigate the influence of the yeast strains on the mycoparasite and the host fungus, in vitro assays were conducted with Sepedonium chrysospermum and Paxillus involutus. Both S. chrysospermum growth inhibitory and stimulating yeast strains were detected among the isolates. The number of S. chrysospermum inhibitory yeast strains increased and the number of S. chrysospermum stimulatory yeast strains decreased in the presence of P. involutus in co-cultures. Low nutrient levels in the culture medium also led to an increased number of S. chrysospermum inhibitory yeast strains and ten yeasts inhibited the mycoparasite in spatial separation by a crosswall. Six yeast strains inhibited P. involutus in dual culture, and the inhibitory P. involutus yeast interactions increased to nine in the presence of S. chrysospermum. Our results suggest that the bolete-associated yeasts influence the growth of the mycoparasitic fungus, which may affect the health of the fruiting bodies.

Evolving Trends in the Dereplication of Natural Product Extracts. 2. The Isolation of Chrysaibol, an Antibiotic Peptaibol from a New Zealand Sample of the Mycoparasitic Fungus Sepedonium chrysospermum

By the application of an HPLC bioactivity profiling/microtiter technique in conjunction with capillary NMR instrumentation and access to the AntiMarin database the conventional evaluation/isolation dereplication/characterization procedures can be dramatically truncated. This approach is illustrated using the isolation of a new peptaibol, chrysaibol (1), from a New Zealand isolate of the mycoparasitic fungus Sepedonium chrysospermum. The unique nature of chrysaibol was recognized by bioactivity-guided fractionation using HPLC bioactivity profiling/microtiter plate analysis in conjunction with capillary NMR instrumentation and the AntiMarin database. 2D NMR techniques, in combination with MS fragmentation experiments, determined the planar structure of chrysaibol (1), while the absolute configurations of the amino acid residues were defined by Marfey's method. Chrysaibol (1) was cytotoxic against the P388 murine leukemia cell line (IC50 6.61 microM) and showed notable activity against Bacillus subtilis (IC50 1.54 microM).

Chrysosporide, a Cyclic Pentapeptide from a New Zealand Sample of the Fungus Sepedonium chrysospermum

A new cyclic pentapeptide, chrysosporide (1), was isolated from a New Zealand sample of the mycoparasitic fungus Sepedonium chrysospermum by bioactivity-guided fractionation. The planar structure was deduced by detailed spectroscopic analysis, and the absolute configurations of the amino acid residues were defined by Marfey's method. As both enantiomers of Leu occurred in chrysosporide, molecular mechanics calculations were applied to the analysis to distinguish between the possible structural isomers. Only the lowest energy conformers of the cyclo-(L-Val-D-Ala-L-Leu-L-Leu-D-Leu) isomer were in agreement with the observed NOEs, suggesting that this was the most probable amino acid sequence for chrysosporide (1).

Microbial parasites associated with Tylenchulus semipenetrans in citrus orchards of Catalonia, Spain

Citrus orchards in Catalonia, Spain were surveyed to identify microbial parasites of Tylenchulus semipenetrans, and their distribution and density. Of 62 orchards, 48 were positively infested with the citrus nematode. Fungal strains were isolated from single eggs, females or second-stage juveniles of the citrus nematode in 69% of the infested orchards. The fungi identified in order of occurrence were Paecilomyces lilacinus, Fusarium solani, Fusarium spp., Cylindrocarpon cylindroides, Verticillium fungicola, Cladosporium cladosporioides, F. oxysporum, Veronaea botryosa, Sepedonium chrysospermum, Volutella ciliata, Exophiala pisciphila and Acremonium sp. Fungal parasitism was related directly to the number of females g−1 of root and magnesium in the soil, and inversely, to the number of eggs g−1 of root and phosphorus in the soil (R 2=0.8654; P<0.0001). Nematode trapping fungi were isolated from soil samples in 29% of the orchards, and Monacrosporium elegans, Arthrobotrys dactyloides, A. javanica, A. superba and A. oligospora var. microspora, were the species present. Endospores of the hyperparasite Pasteuria adhering to vermiform stages of T. semipenetrans were found in 50% of the orchards infested with the citrus nematode.

Assay of cellulolytic activity of cellulose‐decomposing fungi isolated from Egyptian soils

AbstractNinety two fungal species recovered on cellulose — Czapek's agar plates from Egyptian soils were assayed for their cellulolytic activities either at 28 °C (mesophilic) or at 45 °C (thermophilic or thermotolerant). The percentage increase of protein‐nitrogen over those of control was taken as a measure of this ability. At 28°C, the top species in cellulolytic activity were Penicillium oxalicum, Nectria haematococca, Gliocladium catenulatum, Myrothecium verrucaria and Aspergillus niger. The other species showed low, weak or non cellulalytic activity. At 45°C, the highest activity was manifested by Chactomium olivaceum, Sporotrichum thermophilum, Sepedonium chrysospermum, Aspergillus fumigatus, Humicola minima, Rhizomucor pusillus and Thermomyces lanugibnosus. All Penicillium species tested as well as some other fungal species were not capable of utilizing cellulsoe at 45°C.

DNA probe for the identification of Histoplasma capsulatum

A 1.85-kilobase HindIII nuclear DNA probe from Histoplasma capsulatum G217B detected polymorphic restriction fragments within whole-cell DNA from different clinical isolates of H. capsulatum, consistent with the previous system of classification. The probe failed to hybridize to DNA from Blastomyces dermatitidis, Candida spp., Saccharomyces cerevisiae, Sepedonium chrysospermum, and Chrysosporium keratinophilum under low-stringency conditions and therefore may have value as a diagnostic reagent to identify H. capsulatum.

The effects of fungicides on soil fungal populations

Four fungicides, Captan, Dicloran, Thiram and Verdasan were applied at 28-day intervals for 12 consecutive months and their effects on soil fungal numbers and the incidence of individual species were studied. Immediately after application, these fungicides reduced the number of fungal propagules in soil by 23, 11, 36 and 50% respectively compared with control. Captan- and Dicloran-treated soils were rapidly recolonised within 7 days of the application of fungicides. The effects of Thiram and Verdasan were more persistent: the fungal numbers in soils treated with these fungicides did not recover sufficiently to reach control levels throughout the sampling period. Fewer species of fungi were isolated from Thiram- and Verdasan-treated soils than from Captan- and Dicloran-treated soils. Chrysosporium pannorum (Link) Hughes was the principal species isolated from Verdasan-treated soil and the fungus was isolated in increased numbers immediately after application of Verdasan than on subsequent sampling days. Cladosporium cladosporioides (Fres.) de Vries, Mortierella minutissima van Tiegh, Trichocladium asperum Harz, Trichoderma hamatum (Bon.) Bain, and Zygorhynchus moelleri Vuill. were found to be generally tolerant of all four fungicides. However, Botryotrichum piluliferum Sacc. and Marchai, Gliocladium roseum Bain., Humicola fusco-atra Traaen, Sepedonium chrysospermum (Bull.) Link ex Fr., and Trichoderma viride Pers. ex Fr. were generally intolerant of the fungicides but rapidly recolonised the treated soils. While the concentrations of Captan and Dicloran used were fungistatic to T. viride, Thiram and Verdasan were fungicidal.

Microbial transformations of natural antitumor agents: O-demethylation of vindoline by Sepedonium chrysospermum.

Vindoline (1a) was transformed to O-demethylvindoline (1b) by Sepedonium chrysospermum ATCC 13378 in 33% yield. Thin-layer and high-pressure liquid chromatographic methods distinguished 1b from previously reported microbial metabolites of vindoline. The structural proof of 1b was based on its mass spectral fragmentation pattern and on its chemical and nuclear magnetic resonance spectral properties.

ChemInform Abstract: ISOLIERUNG UND KONSTITUTIONSERMITTLUNG VON CHRYSODIN

The constitution of Chrysodin (2), a metabolite of Sepedonium chrysospermum, is proposed on the basis of chemical transformations and physical measurements.

Isolation and constitution of chrysodine

AbstractThe constitution of Chrysodin (2), a metabolite of Sepedonium chrysospermum, is proposed on the basis of chemical transformations and physical measurements.

Notes on Some Hypogeous Fungi from Mexico

SUMMARYAmong 18 species of hypogeous fungi collected in Mexico, Genea asperula, Melanogaster umbrinigleba, and Rhizopogon michoacanicus are described as new species. Gautieria chilensis and G. mexicana are re- described from study of the types. Nearly all the other species represent first records for Mexico: Phycomycetes, Endogone fulva; Ascomycetes, Elaphomyces granulatus, E. reticulatus, Geopora cooperi f. cooperi and Tuber murinum; Basidiomycetes, Hydnangium carneum, Hymenogaster farinaceus, Hysterangium separabile, Leucogaster magnatus, Melanogaster ambiguus var. ambiguus, Rhizopogon sp., Rhizopogon ochraceorubens, and R. subbadius. One specimen of R. ochraceorubens was infected by Sepedonium chrysospermum.

The Biosynthesis of Sepedonin

The origin of each carbon of anhydrosepedonin produced by Sepedonium chrysospermum has been elucidated by carbon-14 tracer method. At first, the degradation pathways adequate to such object was studied. The radioactivity incorporated in sepedonin and anhydrosepedonin was considerably high when acetate-1-14C, acetate-2-14C and formate-14C were used as the precursor. The feature of the labeling pattern of anhydrosepedonin was analogous to those of the other fungal tropolones. The carbon atom derived from formate was almost exclusively situated at C-7 position of the tropolone ring. As a whole, the labeling pattern demonstrated that anhydrosepedonin might be synthesized through the poly-ketomethylene pathway.

Use of 13C in biosynthetic studies. Location of isotope from labelled acetate and formate in the fungal tropolone, sepedonin, by 13C nuclear magnetic resonance spectroscopy

The 13C labelling patterns in sepedonin (3,6,9-trihydroxy-3-methyl-1,3,4,7-tetrahydrocyclohepta[c]-pyran-7-one) isolated from cultures of Sepedonium chrysospermum fed [1-13C]acetate, [2-13C]acetate, and [13C]formate have been elucidated by 13C nuclear magnetic resonance (13C n.m.r.) spectroscopy.

Use of 13C in biosynthetic studies. Incorporation of acetate and formate into the fungal tropolone, sepedonin.

13C-labeled acetate and formate were administered to cultures of Sepedonium chrysospermum. The 13C-labeling patterns in sepedonin (3,6,9-trihydroxy-3-methyl-1,3,4,7-tetrahydrocyclohepta[c]pyran-7-one) were determined by measuring the relative intensities of the 13C–H satellites in the proton magnetic resonance spectra. C-1 was labeled by acetate-1-13C, and C-4, C-5, and the methyl group by acetate-2-13C. Only C-8 was labeled by formate-13C. Malonate-2-14C and succinate-2,3-14C were less efficient precursors than acetate-1-14C, acetate-2-14C, or formate-14C. The available evidence suggests that sepedonin is formed by methylation of a polyketide intermediate derived from acetate and malonate, followed by a stereospecific rearrangement and cyclization.

Use of carbon-13 in biosynthetic studies. Incorporation of isotopically labelled acetate and formate into the fungal tropolone, sepedonin

Abstract : When carbon-13 is used as the isotopic tracer in biosynthetic studies, the labelled atoms in the metabolite can often be determined by n.m.r. spectrometry, without need for chemical degradation. By this technique the biosynthesis of sepedonin in cultures of Sepedonium chrysospermum was studied.

STUDIES IN THE BIOCHEMISTRY OF MICROORGANISMS: PART 117. SEPEDONIN, A TROPOLONE METABOLITE OF SEPEDONIUM CHRYSOSPERMUM FRIES

Two yellow substances were isolated from culture filtrates of the fungus Sepedonium chrysospermum Fries. One of these, named sepedonin, predominates in growing cultures and is believed to be the direct product of metabolism. The second, an anhydro derivative of sepedonin, was probably formed spontaneously in the culture filtrate, and during the isolation process, by chemical dehydration. Sepedonin, C11H12O5with one C-methyl group, gave two dimethyl ethers with diazomethane and has the spectral characteristics of a substituted tropolone. Dehydration under mild conditions afforded anhydrosepedonin, from which a monomethyl ether and two dimethyl ethers were prepared. One of the latter was unstable and rearranged slowly to a third dimethyl ether. By fusion with alkali, anhydrosepedonin was converted to a mixture from which two substituted benzoic acids and a product formulated as 6-hydroxy-4-methyltropolone were separated. The bathochromic displacement of the peaks in the ultraviolet spectrum of anhydrosepedonin compared with those in sepedonin indicated an unsaturated group conjugated to the tropolone ring, confirmed by catalytic reduction to a dihydro derivative. By careful oxidation of one of the dimethyl ethers of anhydrosepedonin with permanganate a substance believed to be a tropolone containing ester and carboxyl substituents was obtained, together with a second product formulated as the 3,4-cyclic anhydride. From these results and supporting n.m.r. and spectral evidence anhydrosepedonin is considered to be a 6-hydroxytropolone with a 2′-methylpyran ring fused at the 4,5,4′,5′-positions. Sepedonin differs only by having a 2′-hydroxy-2′-methyldihydropyran ring as the heterocyclic moiety.

Hypogeous fungi. IV and V

Fruit-bodies of a species of Rhizopogon collected near Burrington, Somerset, in the autumn of 1953, could not be assigned to any known species of this genus and are here described as Rhizopogon reticulatus sp.nov. Other fruit-bodies collected in September 1954 in the New Forest are considered to be those of R. provincialis Tul., the first record of this fungus in Britain. A revised key to British species of Rhizopogon is given. Battarina inclusa (Berk. & Br.) Clem. & Shear, was collected on Tuber puberulum Berk. & Br. at Wotton-under-Edge, Gloucestershire, 7 November 1953. The spores were found to be sparsely echinulate and comparison with type material showed that previous illustrations of these spores (Berkeley & Broome, 1861; Petch, 1938) are incorrect. Sepedonium chrysospermum Fr. on Melanogaster variegatus Vitt. var. broomeianus Berk., collected at Blaise Castle, Bristol, 30 September 1953, is a new British host record. It has since been found also on Rhizopogon provincialis.