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PubMed1994

Heterologous transformation of Zalerion arboricola.

A heterologous DNA-mediated transformation system was developed for the pneumocandin-producing fungus Z. arboricola that was based on either conferral of hygromycin B resistance or complementation of a nitrate reductase mutant. Hygromycin-resistant transformants were selected with plasmid pCSN43 which contains the E. coli hygromycin B phosphotransferase gene under the control of Aspergillus nidulans trpC transcription signals. Transformation frequencies were about four transformants per microgram of circular DNA and could be improved four- to six-fold by linearizing the transforming DNA. The transformants differed from one another with respect to the copy number of the integrated plasmid and the site of integration. Adding an autonomously-replicating sequence (AMA1) from A. nidulans to pCSN43 enhanced transformation three-fold and produced, in addition, numerous abortive transformants. However, it is unlikely that the AMA1 sequence promoted plasmid replication in Z. arboricola. Nitrate reductase mutants of Z. arboricola were isolated by positive selection on chlorate-containing medium, and one mutant was subsequently transformed with pSTA700 which contains the nitrate reductase gene (niaD) from Cephalosporium acremonium. Introduction of the niaD gene restored sensitivity to chlorate in the mutant; therefore, using the niaD gene as a selectable marker provides a system for both positive and negative selection. To our knowledge, this is the first report describing transformation of a member of the genus Zalerion.

Acremonium↗
PubMed1991

Isolation of uridine auxotrophs from Trichoderma reesei and efficient transformation with the cloned ura3 and ura5 genes.

Uridine auxotrophs of the filamentous fungus Trichoderma reesei have been selected using a positive screening procedure with 5-fluoro orotate. Mutants deficient for the orotidine-5'-phosphate decarboxylase gene (ura3 mutants) and for the orotate phosphoribosyl transferase gene (ura5 mutants) have been characterized. The homologous ura3 and ura5 genes have been isolated and used to transform the auxotrophic mutants. Transformation efficiency with these homologous systems is very high (greater than 10(4) transformants per micrograms DNA). Transformation occurred by integration of vector DNA at homologous and ectopic loci. Mitotic instability was observed among some of the transformants. Sequence analysis at the protein level, of the T. reesei ura3 and ura5 genes showed extensive blocks of homology, with the corresponding genes from other organisms. The ura3 gene from T. reesei contains an insertion of 103 aa. A similar sequence is also found inserted in OMPdecase from the pyrenomycetes Neurospora crassa and Cephalosporium acremonium.

Amino Acid Sequence↗
PubMed1991

Polymorphic karyotypes in related Acremonium strains.

A restriction fragment length polymorphism (RFLP) analysis was performed on six related Acremonium strains. With respect to the restriction fragment pattern, all strains of A. chrysogenum were indistinguishable from each other but showed distinctive differences from those of A. strictum, A. flavum and Cephalosporium polyvaleurum. Using pulsed-field gel electrophoresis, we obtained different chromosome patterns from most of the Acremonium strains. Remarkably, the pattern varies in three related A. chrysogenum strains which also differ in their rate of cephalosporin C biosynthesis. The electrophoretic karyotyping was confirmed by the location of rDNA genes on separate chromosomes. Our data indicate that chromosome translocations in industrial strains may be responsible for increased beta-lactam synthesis.

Acremonium↗
PubMed1989

Cloning, sequence analysis and transcriptional study of the isopenicillin N synthase of Penicillium chrysogenum AS-P-78.

A gene (ips) encoding the isopenicillin N synthase of Penicillium chrysogenum AS-P-78 was cloned in a 3.9 kb SalI fragment using a probe corresponding to the amino-terminal end of the enzyme. The SalI fragment was trimmed down to a 1.3 kb NcoI-BglII fragment that contained an open reading frame of 996 nucleotides encoding a polypeptide of 331 amino acids with an Mr of 38012 dalton. The predicted polypeptide encoded by the ips gene of strain AS-P-78 contains a tyrosine at position 195, whereas the gene of the high penicillin producing strain 23X-80-269-37-2 shows an isoleucine at the same position. The ips gene is expressed in Escherichia coli minicells using the lambda phage PL promoter. Some similar sequence motifs were found in the upstream region of the ips gene of P. chrysogenum when compared with the upstream sequences of the ips genes of Cephalosporium acremonium and Aspergillus nidulans. Primer extension studies indicated that the start of the mRNA coincides with a T in position -11 which is located in a conserved pyrimidine-rich sequence, near two CAAG boxes. Clones of P. chrysogenum Wis 54-1255 transformed with the ips gene showed a five-fold higher isopenicillin N synthase activity than the untransformed cultures.

Amino Acid Sequence↗
PubMed1991

Sequence of the cloned pyr4 gene of Trichoderma reesei and its use as a homologous selectable marker for transformation.

We have cloned and sequenced the Trichoderma reesei pyr4 gene encoding orotidine-5'-monophosphate decarboxylase. Comparison of this sequence with that of the equivalent gene from other filamentous fungi suggests that T. reesei is closely related to Cephalosporium acremonium and Neurospora crassa. The cloned pyr4 gene has been used as a homologous selectable marker for transformation of T. reesei. The majority of transformants obtained with circular plasmid were mitotically unstable and contained non-integrated plasmid molecules, sometimes in addition to plasmid integrated in the genome, Linearization of plasmid prior to transformation decreased the transformation frequency but increased the proportion of stable transformation obtained.

Amino Acid Sequence↗
PubMed1975

Four endoparasitic nematode destroying fungi isolated from sand ridge state forest soil.

A survey to determine the endoparasitic nematode destroying fungi located within Sand Ridge State Forest of Illinois was conducted from 1 January to 3 April 1973. A total of seven nematode destroying fungal species were isolated from the collected soil samples. Harposporium helicoides, H. crassum, H. lilliputanum are endoparasitic nematophagous fungi that have been isolated previously from the forest soil. Acrostalagmus gonoides, A. obovatus, Cephalosporium balanoides, and Monacrosporium cionopagum are nematophagous fungal species that had not been isolated previously from Illinois soil. Soil pH's and soil nutrient levels were not important in the isolation frequency of the collected endoparasitic nematode destroying fungi.

Illinois↗
PubMed1986

Fungi on the hair of large mammals in Egypt.

The frequency of occurrence of fungi in 260 hair samples of dog, donkey and cow collected from Veterinary Medicine Hospital of Assiut University was determined. Twenty-three species which belong to fifteen genera were collected. In low frequency, several dermatophytes (Chrysosporium, Microsporum, Arthroderma and Trichophyton) were found as well as some other fungal species pathogenic to man and animals (Aspergillus fumigatus, Stachybotrys chartarum, Scopulariopsis brevicaulis and Cephalosporium acremonium).

Animals↗
PubMed1975

[Microflora of the atmosphere in the city of Trujillo (Peru). III. Genera isolated during the year 1971].

There were 1762 fungi isolated from the atmosphere of Trujillo city (Peru) during the year 1971. These isolants belonged to 23 genera of fungi. The most frequently isolated were: Cladosporium, Penicillium, Fusarium, Stemphylium, Alternaria, Helminthosporium, Aspergillus and Tilachlidium. Nine genera are reported for first time from the air of the city (Tilachlidium, Cephalosporium, Mucor, Aureobasidium, Hormiscium, Trichoderma, Stachybotrys, Paecilomyces and Fisidium). Six genera may be alergenic for asthmatic patients of Trujillo city.

Air Microbiology↗
PubMed1988

Detection of antigen-specific antibodies on lung tissue in a patient with hypersensitivity pneumonitis.

A patient with hypersensitivity pneumonitis showed positive Ouchterlony's immunodiffusion tests against pigeon faecal extract, Cephalosporium and Pullularia antigens. Deposits of immunoglobulins-IgG and IgM antibodies-were detected in a subendothelial position in arterial and venous vessels and on alveolar macrophages in the lung tissue. The IgG deposits in blood vessels belonged to IgG1, IgG2 and IgG3 subclasses and the absorbed IgG on alveolar macrophages to all IgG subclasses. The detection of allergen specific antibodies in lung tissue was made by indirect immunofluorescent staining with FITC conjugated antigen extracts from pigeon faeces and demonstrated the aetiology of this hypersensitivity pneumonitis.

Adult↗
PubMed1995

Genes for beta-lactam antibiotic biosynthesis.

The genes pcbAB, pcbC and penDE encoding enzymes involved in the biosynthesis of penicillin have been cloned from Penicillium chrysogenum and Aspergillus nidulans. They are clustered in chromosome I (10.4 Mb) of P. chrysogenum, but they are located in chromosome II of Penicillium notatum (9.6 Mb) and in chromosome VI (3.0 Mb) of A. nidulans. Expression studies have shown that each gene is expressed as a single transcript from separate promoters. Enzyme regulation studies and gene expression analysis have provided useful information to understand the control of gene expression leading to overexpression of the genes involved in penicillin biosynthesis. Cephalosporin genes have been studied in Cephalosporium acremonium and also in cephalosporin-producing bacteria. In C. acremonium the genes involved in cephalosporin biosynthesis are separated in at least two clusters. Cluster I (pcbAB-pcbC) encodes the first two enzymes of the cephalosporin pathway which are very similar to those involved in penicillin biosynthesis. Cluster II (cefEF-cefG), encodes the last three enzymatic activities of the cephalosporin pathway. It is unknown, at this time, if the cefD gene encoding isopenicillin epimerase is linked to any of the two clusters. In cephamycin producing bacteria the genes encoding the entire biosynthetic pathway are located in a single cluster extending for about 30 kb in Nocardia lactamdurans, and in Streptomyces clavuligerus. The cephamycin clusters of N. lactamdurans and S. clavuligerus include a gene lat which encodes lysine-6-aminotransferase an enzyme involved in formation of the precursor alpha-aminoadipic acid. The N. lactamdurans cephamycin cluster includes, in addition, a beta-lactamase (bla) gene, a penicillin binding protein (pbp), and a transmembrane protein gene (cmcT) that is probably involved in secretion of the cephamycin. Little is known however about the mechanism of control of gene expression in the different beta-lactam producers. The availability of most of the structural genes provides a good basis for further studies on gene expression. This knowledge should lead in the next decade to a rational design of strain improvement procedures. The origin and evolution of beta-lactam genes is intriguing since their nucleotide sequences are extremely conserved despite their restricted distribution in the microbial world.

Amino Acid Sequence↗
PubMed1981

[Molds in foods of the Czechoslovak Socialistic Republik (author's transl)].

The mycoflora of 13.527 g of food powders which were normal upon sensory evaluation as well of 22.017 pieces of surface sterilized grains and nuts was examined in the Czechoslovak Socialist Republic. 147.027 colonies of 44 genera of molds were isolated and identified from samples. Colonies of Penicllium sp., Aspergillus sp., and Cladosporium sp. occured most often, less often or quite infrequently Rhizopus sp., Mucor sp., Absidia sp., Alternaria sp., Circinella sp., Trichoderma sp., Botrytis sp., Paecilomyces sp., Geotrichum sp., Syncephalastrum sp., Scopulariopsis sp., Phoma sp., Auerobasidium sp., Fusarium sp., Thamnidium sp., Cunninghamella sp., Stemphylium sp., Torula sp., Trichothecium sp., Verticillium sp., Cephalosporium sp., Mortierella sp., Neurospora sp., Ostracoderma sp., Arthrinium sp., Monodyctis sp., Papularia sp., Acremonium sp., Chaetomium sp., Chrysosporium sp., Beauveria sp., Cephaliophora sp., Daktylosporium sp., Drechslera sp., Gliomastix sp., Helminthosporium sp., Humicola sp., Monilia sp., Sepedonium sp., Ulocladium sp., and Wallemia sp.

Food Microbiology↗
PubMedDate not supplied

Clusters of genes for the biosynthesis of antibiotics: regulatory genes and overproduction of pharmaceuticals.

In the last decade numerous genes involved in the biosynthesis of antibiotics, pigments, herbicides and other secondary metabolites have been cloned. The genes involved in the biosynthesis of penicillin, cephalosporin and cephamycins are organized in clusters as occurs also with the biosynthetic genes of other antibiotics and secondary metabolites (see review by Martín and Liras [65]). We have cloned genes involved in the biosynthesis of beta-lactam antibiotics from five different beta-lactam producing organisms both eucaryotic (Penicillium chrysogenum, Cephalosporium acremonium (syn. Acremonium chrysogenum) Aspergillus nidulans) and procaryotic (Nocardia lactamdurans, Streptomyces clavuligerus). In P. chrysogenum and A. nidulans the organization of the pcbAB, pcbC and penDE genes for ACV synthetase, IPN synthase and IPN acyltransferase showed a similar arrangement. In A. chrysogenum two different clusters of genes have been cloned. The cluster of early genes encodes ACV synthetase and IPN synthase, whereas the cluster of late genes encodes deacetoxycephalosporin C synthetase/hydroxylase and deacetylcephalosporin C acetyltransferase. In N. lactamdurans and S. clavuligerus a cluster of early cephamycin genes has been fully characterized. It includes the lat (for lysine-6-aminotransferase), pcbAB (for ACV synthase) and pcbC (for IPN synthase) genes. Pathway-specific regulatory genes which act in a positive (or negative) form are associated with clusters of genes involved in antibiotic biosynthesis. In addition, widely acting positive regulatory elements exert a pleiotropic control on secondary metabolism and differentiation of antibiotic producing microorganisms. The application of recombinant DNA techniques will contribute significantly to the improvement of fermentation organisms.

Acyltransferases↗
PubMed1992

Determination of the rate-limiting step(s) in the biosynthetic pathways leading to penicillin and cephalosporin.

This paper is a review of strategies that have been used, or that could be used, to determine the rate-limiting step(s) in the biosynthetic pathways leading to penicillin or cephalosporin. Information is summarized from published material that involves studies with low-producing strains of Penicillium chrysogenum and Cephalosporium acremonium. We also summarize information derived from some high-producing production strains. Identification of the rate-limiting step(s) was of great interest to us as the first step in a rational program to further improve antibiotic titers of these highly developed strains. A number of approaches that could be used to elucidate the rate-limiting step(s) are described herein.

Acremonium↗
PubMed1978

Cellulose-decomposing fungi of salt marshes in Egypt.

Seventy-five species and three varieties which belong to thirty-four genera were identified from 74 soil samples collected from salt marshes in Egypt. The most frequent fungi were Aspergillus fumigatus, Aspergillus niger, Cladosporium herbarum and Alternatia alternata, followed by Aspergillus terreus, Curvularia spicifera and Penicillium notatum. Six genera were of moderate occurrence: Penicillium, Fusarium, Curvularia, Rhizopus, Stachybotrys, and Chaetomium. Five genera were of low occurrence: Paecilomyces, Cephalosporium, Epicoccum, Mucor and Myrothecium.

Cellulose↗
PubMed2003

Industrial production of beta-lactam antibiotics.

The industrial production of beta-lactam antibiotics by fermentation over the past 50 years is one of the outstanding examples of biotechnology. Today, the beta-lactam antibiotics, particularly penicillins and cephalosporins, represent the world's major biotechnology products with worldwide dosage form sales of approximately 15 billion US dollars or approximately 65% of the total world market for antibiotics. Over the past five decades, major improvements in the productivity of the producer organisms, Penicillium chrysogenum and Acremonium chrysogenum (syn. Cephalosporium acremonium) and improved fermentation technology have culminated in enhanced productivity and substantial cost reduction. Major fermentation producers are now estimated to record harvest titers of 40-50 g/l for penicillin and 20-25 g/l for cephalosporin C. Recovery yields for penicillin G or penicillin V are now >90%. Chemical and enzymatic hydrolysis process technology for 6-aminopenicillanic acid or 7-aminocephalosporanic acid is also highly efficient (approximately 80-90%) with new enzyme technology leading to major cost reductions over the past decade. Europe remains the dominant manufacturing area for both penicillins and cephalosporins. However, due to ever increasing labor, energy and raw material costs, more bulk manufacturing is moving to the Far East, with China, Korea and India becoming major production countries with dosage form filling becoming more dominant in Puerto Rico and in Ireland.

Anti-Bacterial Agents↗
PubMed1998

Fungal peritonitis in patients on continuous ambulatory peritoneal dialysis.

The purpose of this study was to analyze the microbiological and clinical features of fungal peritonitis in patients with endstage renal failure treated with continuous ambulatory peritoneal dialysis (CAPD). The diagnosis of peritonitis was based on abdominal discomfort or pain, cloudy peritoneal effluent with an elevated leukocyte count and isolation of fungi from the peritoneal effluent. Amphotericin B, flucytosine, ketoconazole, miconazole and more recently fluconazole were used for antifungal therapy. From 1983 to 1997 13 patients experienced 14 episodes of fungal peritonitis, comprising 3.1% of all episodes of peritonitis in the dialysis centre. Isolates from the peritoneal effluent comprised Candida tropicalis in two cases, Candida parapsilosis in two cases, Candida albicans in one case, Candida lusitaniae in one case,Cephalosporium spp. in three cases, Aspergillus fumigatus in two cases, and an Aspergillus sp., a Trichoderma sp. and a yeast in one case each. In eight cases bacterial infection shortly before the episode of fungal peritonitis was documented. In 12 (86%) cases the peritoneal catheter had to be removed. Four patients died during the treatment, and one patient died 2 months after the end of treatment due to intra-abdominal bleeding from peritoneal adhesions. Only two patients continued CAPD later; the other patients were switched to hemodialysis. It is concluded that fungal peritonitis is a rare but serious complication in CAPD patients with high rates of morbidity, mortality and drop-out from the CAPD programme (85%). The most frequent isolates were Candida spp. A predisposing factor for fungal peritonitis could be a recent bacterial infection treated with antibiotics. Early peritoneal catheter removal is recommended.

Adult↗
PubMed2005

Successful treatment of antifungal- and cryotherapy-resistant subcutaneous hyalohyphomycosis in an immunocompetent case with topical 5% imiquimod cream.

Hyalohyphomycosis is an unusual opportunistic mycotic infection where the tissue morphology of the causative organism is mycelial. Etiological agents, which are not responsible for the otherwise-named infections like aspergillosis, are the species of non-dematiaceous hyaline hyphomycetes including Penicillium, Paecilomyces, Acremonium (formerly known Cephalosporium), Beauveria, Fusarium, and Scopulariopsis. Several cases of Acremonium infection have been described in immunocompromised patients; however it can cause invasive disease in an immunocompetent person very rarely. Optimum therapy of Acremonium infection is unclear because of the limited number of reported cases and conflicting results of therapies. Imiquimod, an imidazoquinoline with potent antiviral, antitumor and immunoregulatory properties, is currently approved for the topical treatment of external anogenital warts and actinic keratosis. Imiquimod has also been found to be effective for other virus-associated dermatologic lesions, including common and flat warts, molluscum contagiosum, and herpes simplex virus type-2 as well as for some cases of cutaneous leishmaniasis. We report herein, for the first time, a case of unusually recalcitrant hyalohyphomycosis of the face due to Acremonium strictum successfully treated with topical 5% imiquimod in an immunocompetent patient, who had failed to respond to various antifungals, including itraconazole, and cryotherapy.

Acremonium↗
PubMed1988

Fungal keratitis in contact lens wearers.

In a retrospective review from 1972 through 1987 of patients with microbial keratitis, fungal infection occurred in four (4%) of 90 cosmetic or aphakic contact lens wearers and in four (27%) of 15 patients using a therapeutic soft contact lens. Predisposing factors included improper lens care by the refractive lens wearers and a chronic epithelial defect with topical corticosteroid use among the therapeutic lens wearers. The responsible organisms in the refractive lens group were Fusarium solani (two patients) and Cephalosporium and Paecilomyces (one patient each), and in the therapeutic lens group Candida (three patients) and Aspergillus (one patient). Filamentous fungi were more likely to be associated with cosmetic or aphakic lens wear, whereas yeasts were more frequently found with therapeutic lens use.

Adult↗