The Penicillium commune Thom and Penicillium clavigerum Demelius fungi--fumigaclavines A and B producers

The type strains Penicillium clavigerum VKM F-447 and P. commune VKM F-3233 are found to produce fumigaclavines A and B. Of the seven other strains of these species, only two strains, P. commune VKM F-3088 and F-3491, possess the ability to synthesize these alkaloids. It is suggested that the five other strains under study either lost such an ability or require very specific conditions for the synthesis of these alkaloids.     

Nephrotoxicity of Penicillium aurantiogriseum and P. commune from an endemic nephropathy area of Yugoslavia

Seven out of nine Penicillium isolates from mouldy maize in Yugoslavia have been differentiated into the adjacent species P. aurantiogriseum and P. commune. Nephrotoxicity of cultured mycelia in the rat has been demonstrated for all isolates of both species and was correlated usefully, though indirectly, with the production of benzodiazepine secondary metabolites, notably auranthine. Shredded wheat (22 g) moulded by an example of each species and fed to a rat over 4 days elicited renal pathology in the P₃ segment of proximal tubules, involving frequent pyknosis and extensive mitosis typical of this as yet uncharacterised toxin. The effect was attributed in P. aurantiogriseum at least partly to the spores. Prominent pathology was elicited by only lg of spores given over 4 days.     

The production of cyclopiazonic acid by Penicillium commune and cyclopiazonic acid and aflatoxins by Aspergillus flavus as affected by water activity and temperature on maize grains

The combined effects of water activity (a_w) and temperature on mycotoxin production by Penicilium commune (cyclopiazonic acid — CPA) and Aspergillus flavus (CPA and aflatoxins — AF) were studied on maize over a 14-day period using a statistical experimental design. Analysis of variance showed a highly significant interaction (P 0.001) between these factors and mycotoxin production. The minimum a_w/temperature for CPA production (2264 ng g^–1 P. commune, 709 ng g^–1 A. flavus) was 0.90 a_w/30 °C while greatest production (7678 ng g^–1 P. commune, 1876 ng g^–1 A. flavus) was produced at 0.98 a_w/20 °C. Least AF (411 ng g^–1) was produced at 0.90 a_w/20 °C and most (3096 ng g^–1) at 0.98 a_w/30 °C.     

Thomitrems A and E,two indole-alkaloid isoprenoids from Penicillium crustosum Thom

Two indole-alkaloid isoprenoids were isolated from extracts of Penicillium crustosum Thom grown on rice. Their structures were elucidated on the basis of various NMR experiments and by comparison to the structurally related penitrems. The two compounds, designated thomitrem A and thomitrem E, contain a 18(19)-double bond and lack the characteristic penitrem 17(18)-ether linkage.     

Intraspecific hybridization between Coprinus cinereus and Schizophyllum commune by PEG-induced protoplast fusion and electrofusion

Two irreversible inhibitors, iodoacetamide and diethylpyrocarbonate, were used to select intraspecific fusion products of two mushroom species, Coprinus cinereus and Schizophyllum commune. Iodoacetamide was the more suitable inhibitor because it gave a low breakage frequency and low survival rate of the cells in the inactivation experiments. Fusion-induced by polyethylene glycol and electro-fusion were compared and, under optimal conditions, gave fusion frequencies of 16.7% to 50.0% and 6.9% to 8.4%, respectively. All fusion progeny were heterokaryons (dikaryons) and had clamp connections. There were no differences in the morphology and fruiting ability of the fusion progeny and those of the heterokaryons generated from mating.     

Structural and Ultrastructural Alterations in BALB/c Mice: Effects of Penicillium Citrinum Metabolites

The aims of this work were to determine the effect of feeding BALB/c mice a diet containing culture materials of a citrinin producing strain of Penicillium citrinum (Thom). Changes in hematological parameters, serum chemistry and histological changes in liver, kidney and heart were determined. After 60 days, control treated (CT) mice appeared normal in all respects, whereas, the mice fed the feeds supplemented with Penicillium (CMT) showed decreased weight gain, lower hematocrits, increased serum alanine aminotransferase (ALT) and clear signs of renal and hepatotoxicity based on histological changes. Changes observed in the liver of CMT mice included portal and lobular infiltration of polymorphonuclear cells, with concomitant hepatocellular necrosis, hepatic steatosis, prominent Kupffer's cells, hemosiderin granules in the cytoplasm of periportal hepatocytes and other lipid inclusions in the surrounding mitochondria were also observed. Our findings suggest that in vivo, P. citrinum Thom metabolites, which contain citrinin, could cause illnesses such as toxic hepatitis or intravascular hemolysis.     

The effect of some amino acids on the growth and biosynthesis of ergot alkaloids and quinocitrinins in the fungus Penicillium citrinum Thom 1910

The effect of some amino acids, added to the medium either during inoculation or in the stationary growth phase, on the growth and biosynthesis of ergot alkaloids and quinocitrinins in the fungus Penicillium citrinum VKM FW-800 has been studied. Exogenously added amino acids were mostly utilized in primary metabolism. When added during inoculation, tryptophan and leucine virtually did not influence fungal growth and synthesis of the alkaloids, whereas the addition of isoleucine enhanced the biomass accumulation. When added in the stationary growth phase, tryptophan stimulated the synthesis of both ergot alkaloids and quinocitrinins. Leucine added in the stationary growth phase did not influence the synthesis of ergot alkaloids but inhibited the synthesis of quinocitrinins. Isoleucine inhibited the synthesis of both ergot alkaloids and quinocitrinins irrespective of the time of its addition to the medium.     

The Fungus Penicillium citrinum Thom 1910 VKM FW-800 Isolated from Ancient Permafrost Sediments As a Producer of the Ergot Alkaloids Agroclavine-1 and Epoxyagroclavine-1

The study of the secondary metabolites of the relict strain Penicillium citrinum VKM FW-800 isolated from ancient Arctic permafrost sediments showed that this fungus produces agroclavine-1 and epoxyagroclavine-1, which are rare ergot alkaloids with the 5R,10S configuration of the tetracyclic ergoline ring system. The production of the alkaloids by the fungus showed a biphasic behavior, being intense in the phase of active growth and slowing down in the adaptive lag phase and in the stationary growth phase. The addition of zinc ions to the incubation medium led to a fivefold increase in the yield of the alkaloids. The alkaloid-producing Penicillium fungi isolated from different regions exhibited the same tendencies of growth and alkaloid production.     

Mitosis in hyphae ofSchizophyllum commune Fr.

Summary In hyphae of the basidiomyceteSchizophyllum commune Fr. mitosis occurs through a longitudinal division of a strand of chromatin, which is followed by a parallel separation of the daughter strands.     

The influence of culture conditions on the biosynthesis of secondary metabolites by Penicillium verrucosum Dierck

A Brazilian strain of Penicillium verrucosum was cultivated under different conditions in a two-step process, in order to verify the influence of nutrients, and of time periods of pre-fermentative and fermentative steps on the biosynthesis of metabolites. Extracellular and intracellular extracts were obtained from each culture in the four different production media used. Chemical profiles of the extracts were obtained by HPLC. Extract trypanocidal activities against trypomastigote forms of Trypanosoma cruzi were evaluated. The time period of incubation in the pre-fermentative and fermentative media, as well as the different nutrients tested, qualitatively and quantitatively modified the production of secondary metabolites by P. verrucosum, and the extract trypanocidal activities.     

Insoluble hydrophobin complexes in the walls of Schizophyllum commune and other filamentous fungi

Two closely related cysteine-rich hydrophobic proteins, Sc3p and Sc4p, of the basidiomycete Schizophyllum commune are developmentally regulated and associated with the walls of aerial hyphae and fruit-body hyphae. They are present in the walls as hot-SDS-insoluble complexes which can be extracted with formic acid. The hydrophobins can then be dissociated by oxidation with performic acid. However, extraction of the walls with trifluoroacetic acid results in both solubilization and dissociation of the hydrophobin complexes into monomers. This suggests that non-covalent interactions are responsible for formation of these insoluble complexes. Carboxymethylation with iodoacetic acid only occurred after reduction with DTT indicating all cysteines in the monomeric hydrophobins involved in intramolecular disulfide bridges. Abundant proteins with similar properties were found in walls from all other filamentous fungi tested, including the basidiomycetes Pleurotus ostreatus, Coprinus cinereus, Agaricus bisporus, and Phanerochaete chrysosporium, the ascomycetes Aspergillus nidulans, Neurospora crassa, and Penicillium chrysogenum, and the zygomycete Mucor mucedo.     

青霉属真菌次级代谢产物的结构类型及其药用活性的研究进展

青霉属(Penicillium)真菌属于腐生类真菌,是自然界中一类重要的分解者。其可以产生多种多样的次级代谢产物。这些结构新颖、功能特殊的次级代谢产物在抗菌、抗氧化、抗肿瘤等药物开发中发挥重要作用,主要由聚酮类、生物碱、萜类、大环内酯等化学结构类型组成。本文综述了青霉属真菌次级代谢产物的结构类型以及丰富的生物药用活性,该内容可为后续青霉属真菌新型天然药物的开发提供研究思路。     

Intergeneric hybridization between Pleurotus ostreatus and Schizophyllum commune by PEG-induced protoplast fusion

Intergeneric hybridization between Pleurotus ostreatus and Schizophyllum commune was studied using PEG-induced fusion. The fusion of protoplasts from auxotrophic mutant strains resulted in the formation of fusion hybrids in the frequencies of 3.6 to 7.3×10^–5. Most of these fusion hybrids were monokaryotic and sterile and no heterokaryosis occurred. Most fusants showed a significantly higher nuclear DNA content when compared to parental strains and no diploids (parent 1 genome plus parent 2 genome) were found. Some fusion hybrids revealed both parental fragments in nuclear and mitochondrial rDNA PCR profiles. AP-PCR (Arbitrarily-primed Polymerase Chain Reaction) fingerprints also indicated that most of the fusion products were recombinant hybrids.     

Molecular characterization of ochratoxin A producing strains of the genus Penicillium

Sixty-six strains classified as P. verrucosum based on morphological criteria were characterized by molecular methods like RAPD, AFLP and ITS sequencing. Two groups could be identified by RAPD and AFLP analyses. The two RAPD as well as the two AFLP groups were completely coincidental. Strains in the two groups differed in their ability to produce ochratoxin A, with group I containing mainly high producing strains, and group II containing moderate to non-producing strains. The strains from group I originate from foods, such as cheeses and meat products, while the strains from group II originate from plants. The ribosomal ITS1-5.8S-ITS2 sequences were similar, except for two single nucleotide exchanges in several strains of each group. A chemotaxonomical analysis of some of the strains identified differences between the groups in secondary metabolite production. Strains from group I possessed the chemotype of P. nordicum and strains from group II that of P. verrucosum. The differences at the RAPD and AFLP level, which parallel the chemotypic differences, are consistent with the recent reclassification of ochratoxin A producing penicillia to be either P. verrucosum or P. nordicum. The homolgy between the ITS sequences however indicates phylogenetic relationship between the two species.     

Heterokaryon formation in the basidiomycete Schizophyllum commune by electrofusion of protoplasts

Summary Conditions for high frequency electrofusion of protoplasts from the basidiomycete Schizophyllum commune are described. Visual inspection revealed up to 30% of the protoplasts engaged in fusion. Using complementing nutritional mutations, nearly 7% of the regenerated protoplasts could be recovered as heterokaryotic mycelia. The method is probably equally applicable to other basidiomycetes such as Agaricus bisporus, permitting the recovery of fusion products in the absence of selection markers.     

Toxins from strains of <Emphasis Type="Italic">Penicillium chrysogenum</Emphasis> isolated from buildings and other sources

In 2004, Scott et al. (Mycologia 2004; 96: 1095–1105) determined that there are four molecular species within P. chrysogenum, one of which (clade 4) was dominant in isolates in house dust in ~100 homes in southern Ontario, Canada. We collected additional strains from buildings across Canada and obtained some from DAOM. The large majority of our strains were in clade 4, with a modest number of strains in Clade 1. Because these strains came from across Canada, the dominance of clade 4 in buildings is apparently widespread. Most strains tested produced penicillin G, roquefortine C and unexpectedly, meleagrin in high yield. Additionally, there appeared to be strains differentiated by their ability to accumulate xanthocillin X. These studies allowed focused toxicity studies in vivo and with primary lung cell cultures to be undertaken on the basis of reliable information of the toxins that should be studied.     

Exocellular hydrolases from Penicillium ulaiense

Penicillium ulaiense exhibited carboxymethylcellulase, pectinase, protease, amylase and phenolase activities, while no xylanase, cellulase, lipase or ligninase activities were found. Pectinolytic action was studied in liquid medium, showing low levels of pectinesterase and pectinase production. No mycotoxins were detected by thin-layer-chromatography.The authors are with INIQUI, Universidad Nacional de Salta, Buenos Aires 177, 4400 Salta, Argentina     

Production and partial purification of naringinase by Penicillium decumbens PTCC 5248

Penicillium decumbens PTCC 5248 produced naringinase when grown in a medium contained naringin as a source of carbon. Rhamnose also induced production of naringinase. Prunin disappeared as the time of enzymatic reaction increased. On fractionation with isopropanol 24-fold purification was achieved. Optimum pH and temperature for naringinase activity were determined to be 4.5 and 55 °C respectively. The K_m value of the enzyme with respect to naringin was found to be 1.7 mM. Citric acid, glucose, Ca²⁺, Mg²⁺, Zn²⁺ all inhibited naringinase activity.     

Pectinase production by Penicillium frequentans

High activities of extracellular pectinase with viscosity-diminishing and reducing groups-releasing activities were produced by Penicillium frequentans after 48 h at 35°C, in agitated cultures supplemented with 0.5% citrus pectin and initial pH of 2.5. Under these conditions the fungus also produced high activity of pectinesterase. At an initial pH of 7.0 or 8.0, pectin lyase activity was also detected. Enzyme activity releasing reducing sugars was more stable at 50°C than viscosity-diminishing activity. Both activities were maximal at pH 2.5 to 5.2 and at 55°C.The authors are from the Faculdade de Ciências Farmacêuticas de Ribeirão Preto da Universidade de São Paulo, Avenida do Café, s/n^o, Bairro Monte Alegre, 14.049 Ribeirão Preto, S.P., Brazil.     

Isolation and metabolite production by Penicillium roqueforti,P. paneum and P. crustosum isolated in Canada

Penicillium roqueforti, P. crustosum and P. paneum grow on ensiled grain and recycled feed unless properly treated. The former two species occur also on cut lumber in Canada. These are known to produce a number of secondary metabolites including roquefortine. In cooler dairy production areas, including Scandinavia and North America, cattle toxicosis has been associated with silage contaminated by these fungi. We collected strains associated with cow or cattle toxicoses. The principal metabolites were determined making use of a new extraction method and analysis combining HPLC, LC/MS/MS, and LC/NMR. Penicillium roqueforti and P. crustosum required amino acid nitrogen for metabolite formation and their toxins were formed under conditions of low oxygen (20–30% saturation). Production of roquefortine C occurred on depletion of the available nitrogen and penitrem A on depletion of carbon source. Yield was reduced by excess carbon. Medium osmotic tension (a_w) affected metabolite production by the two species differently. Penicillium paneum was associated with ill-thrift of dairy cows and P. roqueforti was associated with more serious symptoms. Our data suggest a physiological basis for the common occurrence of roquefortine C in silage without serious consequences and the alternative, the presence of roquefortine C and toxicoses. The strain isolated from lumber was the best producer of the toxins studied. This is the first report of the toxigenic potential of P. roqueforti and P. paneum from Canada.