Microsporum Cookei Research Articles

Detection and identification of dermatophyte fungi in clinical samples using a commercial multiplex tandem PCR assay

We evaluated the performance of a commercial multiplex tandem polymerase chain reaction (PCR) for detection of dermatophytes and other fungi in skin and nail specimens by (1) testing a range of fungal and bacterial reference cultures, (2) retrospectively testing a set of skin and nail specimens with known microscopy and culture results, and (3) prospectively testing skin and nail specimens in parallel to microscopy and culture. The AusDiagnostics Dermatophytes and Other Fungi assay accurately detected and identified a range of common dermatophytes to species, species complex or genus level, as well as Candida, Aspergillus and Scopulariopsis spp. It was unable to detect uncommon dermatophytes such as Nannizzia fulva (previously Microsporum fulvum), and Paraphyton cookei (previously Microsporum cookei). PCR identified a dermatophyte in 25.9% of prospective specimens which were culture negative. Sensitivity, specificity, positive predictive value, and negative predictive value were highest where microscopy and PCR results were combined, versus microscopy and culture combined, which highlights the significant contribution of microscopy in the diagnostic pathway. This assay has the potential to reduce the workload and results turnaround time associated with culturing and identification of dermatophytes, although microscopy remains important.

First Report on the Occurence of Dermatophytes of Microsporum Cookei Clade and Close Affinities to Paraphyton Cookei in the Harmanecká Cave (Veľká Fatra Mts., Slovakia)

Keratinolytic and keratinophilic fungi, such as dermatophytes, are frequently a cause of infections in humans and animals. Underground ecosystems are inhabited by various animals and are of interest for tourists. Therefore, the main goal of our research was the first evaluation of sediment and soil samples taken inside and outside the Harmanecká Cave in Slovakia for the occurrence of keratinolytic and keratinophilic fungi. Tests with Vanbreuseghema bait, as well as phenotyping and molecular methods, showed that all of the sampling sites contained ten isolates, all of the same species of keratinophilic fungi, belonging to the Microsporum cookei clade and with close affinities to Paraphyton cookei (Ajello) Y. Gräser, Dukik & de Hoog. Our research showed that, dependent on the medium, its mycelium varied in color and showed different growth rates. It also produced metabolites alkalizing DTM (dermatophyte test medium) medium. It dissolved keratin in in vitro hair perforation tests and was able to utilize most substrates in the API® 20C AUX, except for MDG (α-methyl-D-glucoside). In addition, the vegetative structures of mycelium were viable after storage at temperatures from −72 to −5 °C for 56 days, and actively grew after 28 days at a temperature range from 15 to 37 °C, with 25 °C being optimal. It showed weak, but active, growth at 5 and 10 °C after 56 days. We can assume that due to the low temperature in the caves, this fungus will not be able to actively grow rapidly on keratin substrates, but the contact with mammals, along with other favorable factors, might lead to an infection.

English

The wastewater in Bagru and Jharna area (Rajasthan) is rich in pathogenic and non-pathogenic keratinophilic fungi including dermatophytes. Most of the fungal isolates from the waste water have already been reported as dermatophytes causing infections of skin, scalps or hair. This study deals with the isolation and characterization of keratinophilic fungi from different water samples of Bagru and Jharna area (Rajasthan). Eighteen different fungi were isolated out of twenty water samples using a spread plate method. These fungal isolates were Epidermatophyton floccosum, Microsporum ferrugineum,Microsporum gypseum, Microsporum cookei, Microsporum canis, Trichophyton rubrum,Trichophyton mentagrophytes, Trichophyton concentricum, Trichophyton verrucosum,Trichophyton violaceum, other fungi were Aspergillus niger, Aspergillus fumigatus,Aspergillus flavus, Aspergillus terreus, Rhizopus oryzae, Penicillium sp., Fusarium oxysporum and Chrysosporium tropicum. Our result concluded that these isolated fungi are pathogenic for animals and human beings. Keratinophilic fungi play an important role in degradation of keratin and they are known to cause superficial cutaneous infections.   Key words: Keratinophilic fungi, pathogenic, non-pathogenic, spread plate method, superficial cutaneous infections, dermatophytes.

Purification and characterization of a 33 kDa extracellular proteinase from Microsporum cookei

Summary Objective An extracellular proteinase synthesized by the geophilic dermatophyte Microsporum cookei has been purified and characterized. Material and methods The soil isolate of M. cookei was cultivated in modified Czapek-Dox liquid medium containing 0.1% bacteriological peptone and 1% glucose as the nitrogen and carbon sources. Purification of the proteinase was accomplished by (NH 4 ) 2 SO 4 precipitation, followed by ion-exchange chromatography. Results Analysis of the enzyme by SDS-PAGE revealed a single polypeptide chain with an apparent molecular mass of 33 kDa. A keratinolytic activity was evidenced for the enzyme by the keratin azure test. The inhibition profile and the good activity of the enzyme towards the synthetic substrate N -succinyl-Ala-Ala-Pro-Phe- p -nitroanilide suggested that it belongs to the subtilisin group of serine proteinases. Conclusion The keratinolytic properties of M. cookei suggest that this fungus may be an alternative for the recycling of industrial keratinic wastes.

Microsporum mirabileand its teleomorphArthroderma mirabile, a new dermatophyte species in theM. cookeiclade

A novel dermatophyte species is described in the Microsporum cookei clade. It differs significantly from known taxa in the two molecular markers analyzed, i.e., ITS and partial β-tubulin (BT2). Morphologically the species was characterized by smooth- or only slightly rough-walled conidia, but isolates rapidly became pleomorphic with sparse, smooth- and thick-walled macroconidia in addition to microconidia. A teleomorph was found after mating.

Keratinophilic fungi in activated sludge of wastewater treatment plants with MBR in Berlin, Germany

Seventy-two samples of aerobic and anoxic activated sludge were collected from two wastewater treatment plants (36 from each) with membrane bioreactors (MBR) in Berlin (Germany) to determine the presence of cycloheximide-resistant, keratinophilic fungi using the hair-baiting technique. This is the first study on the occurrence of these fungi in MBR sludges. Forty-six fungal species belonging to 21 genera were isolated and identified (41 species and 21 genera versus 36 species and 19 genera from aerobic and anoxic sludge samples, respectively). Twelve species were dermatophytes or closely related fungi: Chrysosporium asperatum, C. georgii, C. indicum, C. keratinophilum, C. tropicum, C. pannorum, Microsporum cookei, M. ferrugineum, M. gypseum, Trichophyton ajelloi, T. mentagrophytes and T. terrestre. The other 32 species, included membe rs of Acremonium, Alternaria, Aspergillus, Candida, Chaetomium, Cladosporium, Fusarium, Geotrichum, Gliocladium, Gymnoascus, Mucor, Paecilomyces, Penicillium, Scopulariopsis, Sporothrix, Trichoderma, Verticillium and unidentified yeasts. The fungi isolated are pathogenic or potentially pathogenic to humans and animals, and their occurrence in activated sludge poses a health risk to wastewater treatment workers and the environment.

DERMATOPHYTES, RELATED KERATINOPHILIC AND OPPORTUNISTIC FUNGI IN INDOOR DUST OF HOUSES AND HOSPITALS

Dermatophytes, related keratinophilic and opportunistic fungi were isolated from indoor dust samples of 46 hospitals and 47 houses in Kanpur. A total of 19 fungi represented by 11 genera were isolated by the hair-baiting technique from 230 and 235 samples from hospitals and houses respectively. The isolated fungi are Acremonium implicatum (Indian Type Culture Collection) ITCC 5266, A. strictum (Germplasm Centre for Keratinophilic Fungi) GPCK 1137, Aphanoascus fulvescens GPCK 1081, Arthroderma simii GPCK 1275, Chrysosporium queenslandicum ITCC 5270, C. indicum ITCC 5269, C. pannicola GPCK 1022, C. tropicum GPCK 1269, Ctenomyces serratus ITCC 5267, Gymnoascus reessii ITCC 5265, Malbranchea fulva GPCK 1075, Malbranchea pulchella ITCC 5268, Micosporum gypseum GPCK 1038, Microsporum cookei GPCK 2001, M. fulvum GPCK 2002, Paecilomyces lilacinum GPCK 1080, Penicillium expansum GPCK 1082, Trichophyton mentagrophytes GPCK 2003 and T. terrestre GPCK 2004. In hospitals, the minimum frequency was of Ctenomyces serratus ITCC 5267 while the maximum frequency was of Arthroderma simii GPCK 1275. In houses, Chrysosporium queenslandicum ITCC 5270 and C. tropicum GPCK 1269 were with minimum and maximum frequencies respectively. This makes the first report of these fungi with keratinolytic ability in the indoor dust of hospitals and houses.

P247 Fertility and viability rates of hydatid cysts in slaughtered animals in the Mazandaran Province, Northern Iran

A total of 23 soil samples of potted plants was collected from hospitals in Sari, Iran. Each sample contained approximately 200 g soil, taken from a depth of 0–10 cm of the pots. Samples were analysed by two different methods. (1) Culture on Sabouraud's dextrose agar medium containing chloramphenicol (SC); cultured fungi were identified by macroscopic and microscopic characterization. (2) The hair-baiting technique (HBT) was used to isolate the keratinophilic fungi. After culture on SC medium, 100% of plates were positive for fungal growth, and in total 1150 colonies with 13 different types of fungi were isolated. Penicillium spp. (52%), Acremonium spp. (20%), Paecilomyces spp. (11.9%), Cladsporium spp. (3.7%) and Aspergillus spp. (3.1%) were the predominant fungal species. Rhizopus spp. (0.1%) were less frequent. Keratinophilic fungi such as Microsporum gypseum, Microsporum cookei and Chrysosporium spp. were isolated using HBT. The presence of pathogenic fungi such as Cladosporium spp, Aspergillus spp, M. gypseum, and M. cookei in potted plants in hospitals represents a potential source of nosocomial infection.

Study of diseases of the grey squirrel (Sciurus carolinensis) in Italy. First isolation of the dermatophyte Microsporum cookei

The ecological risks connected with the introduction of the North American grey squirrel (Sciurus carolinensis) in Italy are many. Of particular importance is the conservation of the native red squirrel (S. vulgaris) population, since the experience from the British Isles showed that where the grey squirrel was introduced, the autochthonous red squirrel became extinct. To determine the health status of grey squirrels trapped and euthanasized during an eradication campaign in the Piedmont region, various analyses were carried out. This paper describes a preliminary mycological investigation. Microsporum cookei, a geophilic dermatophyte, was isolated for the first time from grey squirrels.

Fungal morphogenesis induced by natural and synthetic substances: Herniarin-induced alterations in the dermatophyte Microsporum cookie Ajello

The effects of either synthetic or natural substances on the normal morphogenetic processes in fungi are reviewed. Original results concerning the changes induced in the dermatophyte Microsporum cookei Ajello by the UVA-activated coumarin, herniarin, are reported. Alterations in the shape and wall assembly of parietal components are discussed on the basis of the most recent knowledge on the formation and growth of fungal hyphae.

Seasonal 4-year investigation into the role of the alpine marmot (Marmota marmota) as a carrier of zoophilic dermatophytes1

Two hundred and six samples of alpine marmot (Mamota marmota) hair (148 from adults and 58 from young subjects), 102 soil samples from the entrances to the burrows of the above individuals and 20 control specimens (obtained from adjoining areas away from the burrow systems where the rodents are not usually present) were examined from May 1994 to September 1997. Seventy-five isolates belonging to six species of dermatophytes were found in 69 of the 206 hair samples examined (33.5%). Two species were zoophilic, Microsporum canis (7.8%) and Trichophyton mentagrophytes (11.2.%), and four geophilic, Microsporum cookei (2%), M. gypseum (5.8%), Trichophyton ajelloi (3.9%) and T. terrestre (5.8%). The prevalence of each species in the hair samples did not change significantly according to year, season (chi-squared test [limit significance: P <0.05] gives no significant values [P>0.05] both in year and in season comparison) or age/sex (adult versus juvenile: P=0.1; male versus female: P=0.8) of the marmot. Twenty-three of the 102 soil samples (22.5%) were positive for dermatophytes found in the hair of marmots from the same burrow systems. Five of the 20 control soil samples (25%) were positive for dermatophytes. One isolate of M. gypseum, three of T. terrestre and one of T. mentagrophytes were obtained. Compared with other free-ranging rodent hosts studied in Europe, this mycoflora is characterized by the presence and relatively high prevalence of M. canis, frequently reported in symptomatic and asymptomatic cats, dogs and fur animals. M. canis has not been isolated in other rodents in the wild. However, it has recently been reported in asymptomatic foxes (Vulpes vulpes) from northern Italy. The close link between V vulpes and M. marmota, with the former representing the most important mammal predator of the latter in the Alps (only a fraction of the predator's attacks result in the death of the rodent) may have favoured the adaptation of M. canis to this rodent host. The stable character of the M. canis/M. marmota relationship (no seasonally or annually related difference in the prevalence of this dermatophyte has been found) suggests the inclusion of the alpine marmot in the reservoir of this zoophilic pathogenic agent. In this situation, hibernation in labyrinthine burrow systems, where temperature and moisture ranges are quite uniform the whole year round, may favour the viability of M. canis arthroconidia, whose survival in mountain habitat might otherwise be compromised. This seems to be confirmed by the fact that the fungus has never been found in the control samples collected at a distance of 300 m from the outer edge of the sampled burrow systems.

A survey on the pathogenic fungi in soil samples of potted plants from Sari hospitals, Iran

A total of 23 soil samples of potted plants was collected from hospitals in Sari, Iran. Each sample contained approximately 200 g soil, taken from a depth of 0–10 cm of the pots. Samples were analysed by two different methods. (1) Culture on Sabouraud's dextrose agar medium containing chloramphenicol (SC); cultured fungi were identified by macroscopic and microscopic characterization. (2) The hair-baiting technique (HBT) was used to isolate the keratinophilic fungi. After culture on SC medium, 100% of plates were positive for fungal growth, and in total 1150 colonies with 13 different types of fungi were isolated. Penicillium spp. (52%), Acremonium spp. (20%), Paecilomyces spp. (11.9%), Cladsporium spp. (3.7%) and Aspergillus spp. (3.1%) were the predominant fungal species. Rhizopus spp. (0.1%) were less frequent. Keratinophilic fungi such as Microsporum gypseum, Microsporum cookei and Chrysosporium spp. were isolated using HBT. The presence of pathogenic fungi such as Cladosporium spp, Aspergillus spp, M. gypseum, and M. cookei in potted plants in hospitals represents a potential source of nosocomial infection.

Study of diseases of the grey squirrel (Sciurus carolinensis) in Italy. First isolation of the dermatophyte Microsporum cookei

Study of diseases of the grey squirrel (Sciurus carolinensis) in Italy. First isolation of the dermatophyte Microsporum cookei

Study of diseases of the grey squirrel (Sciurus carolinensis) in Italy. First isolation of the dermatophyteMicrosporum cookei

The ecological risks connected with the introduction of the North American grey squirrel (Sciurus carolinensis) in Italy are many. Of particular importance is the conservation of the native red squirrel (S. vulgaris) population, since the experience from the British Isles showed that where the grey squirrel was introduced, the autochthonous red squirrel became extinct. To determine the health status of grey squirrels trapped and euthanasized during an eradication campaign in the Piedmont region, various analyses were carried out. This paper describes a preliminary mycological investigation. Microsporum cookei, a geophilic dermatophyte, was isolated for the first time from grey squirrels.

Isozyme variation within and among populations of Microsporum species.

Isozyme variation among 54 isolates of Microsporum canis, 18 Microsporum cookei isolates and two Diheterospora isolates were studied using starch gel electrophoresis. Of eight enzymes examined, four were polymorphic (EST, G6P, MDH and PEP), having from two to four electrophoretic forms. Within each species, consistent and reproducible isozyme patterns of the eight enzyme systems were obtained. Phenotypic diversity (H) in M. canis was higher than in M. cookei (H = 0.459 and H = 0.408 respectively), but phenotypic differentiation of M. canis isolates from different geographical regions (Auckland, Wellington and Palmerston North, New Zealand) was low, with a proportion of total diversity (Gst) of 0.151 found among the localities. The results suggest that the isolates of M. canis from different geographical regions are closely related, supporting the theory of a common lineage.

Isolation of fungi from soil using the keratin-baiting technique

Of 236 soil samples baited with wool, some 71.2% (168) produced fungal growth. Gliocladium (25.0%), Paecilomyces (14.8%), Trichophyton (11.9%) species were the most prevalent in soil moistened with sterile distilled water (SDW) containing antibiotics. On the other hand, in soil moistened with SDW only, Trichophyton (32.6%), Paecilomyces (27.5%), Diheterospora (16.5%), Gliocladium (13.6%) and Fusarium (13.1%) species were more common. Of the known potential pathogens, the Paecilomyces and Fusarium species were frequently isolated from soil collected in parks, cleared areas, paddocks, rivers and roadsides. All five sites are areas of human and animal activity. The keratinolytic species were Microsporum cookei, M. gypseum complex, Trichophyton ajelloi and T. terrestre, which are regarded as nonpathogens with the exception of M. cookei and M. gypseum complex.

Partial characterization of proteolytic enzymes of Microsporum canis and Microsporum cookei.

Characterization by proteinase inhibitors of the enzymes produced by Microsporum spp. revealed that Microsporum canis and Microsporum cookei produce serine proteinase(s), but only M. canis expresses aspartic and cysteine proteinases and probably a metalloproteinase. Both M. canis and M. cookei expressed metalloelastinolytic proteinases. All the proteinase types have been implicated in the pathogenicity of a wide range of microorganisms.

Antifungal effects of α‐terthienyl from Tagetes patula on five dermatophytes

AbstractAlpha‐terthienyl (αT), a thiophene compound isolated from Tagetes patula (Asteraceae), exhibits antifungal activity towards five strains of dermatophytes (Trichophyton mentagrophytes, T. rubrum, T. violaceum, Epidermophyton floccosum, Microsporum cookei). αT plus UVA irradiation for 90 min acted as a fungistatic at concentrations between 6 μM and 24 μM. Between 1 and 10 days after irradiation, the fungal growth was reduced or arrested with marked responses for T. mentagrophytes, T. rubrum and M. cookei. The ultrastructural events that occur in Trichophyton mentagrophytes after treatment were studied by electron microscopy. In the dark, αT caused no important ultrastructural modifications within the hyphae. After UVA irradiation the photoactive compound caused damage to membranes of the nucleus, mitochondria and endoplasmic reticulum. Plasmolytic and autolytic changes resulted in plasma membrane breakage and in cell wall aberrations. UVA‐activated αT would appear to target protein‐rich membranes of the dermatophytes.

Antifungal activity of some 2,2':5',2"-terthiophene derivatives.

The dermatophyte Microsporum cookei Ajello was treated with nine new natural and synthetic 2,2':5',2"-terthiophenes to determine their possible antifungal activity. In the dark the thiophenes were inactive, while when photoactivated with UV-A they induced a remarkable reduction in the growth rate of the fungus. The only exception was (E)-N-(2-methylpropyl)-3-(2,2':5',2"-terthien-5-yl)-propenamide , which was not fungistatic even at the highest dose tested (24 microM). The more active compounds were 3'-methoxy-2,2':5',2"-terthiophene and 3'-methylthio-2,2':5',2"-terthiophene, whose activity seems to be related to the presence of a substituent in the 3' position of the central ring of thiophenes. Transmission electron microscopic observations demonstrated the photoactive nature of the synthetic molecules to be similar to that of alpha-terthienyl, a natural thiophene present in some Asteraceae. The dark treatment caused only the accumulation of the compound in vacuoles, without other evident alterations. After UV-A irradiation the activated thiophene causes severe modifications to the endomembrane system, probably via oxygen-dependent mechanism.

The occurrence of keratinophilic fungi in sewage sludge from Egypt

The keratinophilic fungi of 40 sewage sludge samples from Upper Egypt were studied using a goat hair-baiting technique. 43 species representing 22 genera were isolated, 17 species of which were dermatophytes and closely related fungi: Chrysosporium state of Arthroderma tuberculatum, C. asperatum, C. georgii, C. indicum, C. keratinophilum, C. pseudomerdarium, C. queenslandicum, Chrysosporium state of Thielavia sepedonium, C. tropicum, Microsporum cookei, M. gypseum, Myceliophthora anamorph of Corynascus novoguineensis, M. vellerea and Trichophyton terrestre. 26 species of cycloheximide resistant fungi were collected and these included members of Acremonium, Aspergillus, Alternaria, Chaetomium, Cladosporium, Cunninghamella, Emericella, Fusarium, Geotrichum, Penicillium and others.