Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “MICROSPORUM”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources
PubMed1971

Regulation and self-inhibition of Microsporum gypseum Macroconidia germination.

Germination of Microsporum gypseum macroconidia was accompanied by the release of alkaline protease, calcium ions, and inorganic phosphate into the germination fluid. The rate of germination was greatest during the first 2 hr, decreasing thereafter. This decrease in rate was accompanied by a decrease in protease activity, which was caused by an interaction of the enzyme with the inorganic phosphate released from the spores and accumulated in the germination medium after 2 hr. Germination of high spore densities was regulated by the ratio of released phosphate to protease protein, resulting in a constant percentage of germination at both high and low spore densities. A germination-defective mutant strain failed to germinate normally and released excessively high concentrations of phosphate into the germination medium during the initial 2 hr of incubation. Addition of calcium ions to germination mutant macroconidia stabilized spore morphology, prevented protease inactivation, and allowed normal germ-tube outgrowth. The germination of macroconidia appears to be regulated by the release of phosphate ions, which then inhibit the alkaline protease.

Calcium↗
PubMed1972

Isolation and characterization of Microsporum gypseum lysosomes: role of lysosomes in macroconidia germination.

Three types of lysosomes containing either acid protease, alkaline protease, or phosphodiesterase were isolated from a Microsporum gypseum macroconidial homogenate on Ficoll gradients. The acid protease was contained in an assimilative lysosome since its activity was affected by the complexity of the exogenous nitrogen source. Ultracentrifugation and electron microscopy revealed that the alkaline protease-containing vesicles were associated with the spore coat material prior to macroconidial germination. During macroconidial germination, zones of spore coat hydrolysis were seen surrounding these vesicles. Other larger vesicles, believed to contain the phosphodiesterase, were also observed in the spore coat during macroconidial germination.

Acid Phosphatase↗
PubMed1974

Phosphate-mediated alteration of the Microsporum gypseum germination protease specificity for substrate: enhanced keratinase activity.

Inorganic phosphate was found to decrease the caseinolytic and ethyl-esterase activities of the Microsporum gypseum germination protease. The germination protease possessed exokeratinase (beta-keratinase) activity immediately after release from the fungal spore. After phosphate treatment of the enzyme, the germination protease also possessed endo-keratinase (alpha-keratinase) activity. Phosphate altered the protease's pH optimum from 9.0 to 7.0 and decreased the molecular weight from 33,000 to 16,000. These values were identical to those found for the keratinase. Alpha- and beta-keratinase activities were stimulated in excess of 200-fold by disulfide reducing agents. Natural and suspected keratin degradation products also enhanced keratinase activity. Cell fractionation and in vitro conversion of the alkaline germination protease into a functional keratinase suggested that the subunits comprising the germination protease and the keratinase were of a common origin.

Animals↗
PubMed1974

Changes in Microsporum gypseum mycelial wall and spore coat glycoproteins during sporulation and spore germination.

Ethylenediamine-soluble glycoproteins were extracted from isolated Microsporum gypseum hyphal walls during sporulation and from spore coats before and after germination. This study was carried out to identify a sporulation-specific cell wall protein that possibly served as a substrate for the alkaline protease which initiated the macroconidial germination of this fungus. Analyses revealed that water-insoluble glycoprotein accounted for 10% of the ungerminated spore coat but only for 4 to 5% of the mycelial wall dry weight. This fraction was modified in its amino acid composition during sporulation, and it decreased in protein content during spore germination. Water-soluble glycoprotein, which accounted for approximately 3 to 3.5% of either the spore coat or mycelial wall dry weight, was of similar amino acid composition from both sources and did not decrease in protein content upon spore germination. The water-insoluble glycoprotein was found to be rich in leucine, aspartic acid, glycine, glutamic acid, and phenylalanine residues. The water-soluble glycoprotein was rich in proline, threonine, glycine, serine, glutamic acid, and alanine.

Amino Acids↗
PubMed1967

Carbon catabolism and synthesis of macromolecules during spore germination of Microsporum gypseum.

Either d- or l-leucine (10(-3)m) and unsaturated long-chain fatty acids such as oleic, linoleic, and arachidonic (10(-4)m) significantly stimulated macroconidia germination of Microsporum gypseum. Saturated long-chain fatty acids did not affect germination, whereas saturated short-chain fatty acids such as caprylic, hexanoic, and butyric were completely inhibitory. Germination was followed by an increase in endogenous respiration and a decrease in dry weight of approximately 5% at 4 hr. Endogenous fatty acids and soluble carbohydrates were utilized significantly during germination. Tritiated leucine, uridine, and thymidine were incorporated respectively into protein, ribonucleic acid (RNA), and deoxyribonucleic acid (DNA) fractions within the first 5 min of germination. Incorporation of oleic-1-C(14) into RNA and protein was significantly increased after germ tube development. Net synthesis of RNA and protein started prior to germ tube protrusion. Increase in DNA could be detected only later. A significant increase in RNA and protein during the 4th hr of germination was correlated with vegetative development. Inhibition of respiration and incorporation of leucine-H(3) and uridine-H(3) into corresponding macromolecules by dl-fluorophenylalanine and phenethyl alcohol started before germ tube appearance. Griseofulvin significantly inhibited incorporation of uridine-H(3) and thymidine-H(3), but not of leucine-H(3). This inhibition occurred only after initial vegetative development. In contrast to the two other inhibitors, which substantially inhibited germination, griseofulvin only slightly retarded the period of germination and did not affect respiration.

Alcohols↗
PubMed1967

Immunological studies on dermatophytes. I. Serological reactivities of neutral polysaccharides with rabbit antiserum to Microsporum quinckeanum.

Antiserum produced in the rabbit to autoclaved mycelial suspensions of Microsporum quinckeanum reacted with three neutral polysaccharides isolated from each of five species of dermatophytes, M. quinckeanum, Trichophyton granulosum, T. interdigitale, T. rubrum, and T. schönleinii. The serological reactivities of these polysaccharides, grouped as galactomannans I, galactomannans II, and glucans, were compared by qualitative precipitation analyses in gel and quantitative complement-fixation analyses. Significant differences were found among the glucans and galactomannans II but not among the galactomannans I of these species.

Complement Fixation Tests↗
PubMed1968

Immunological studies on dermatophytes. 3. Further analyses of the reactivities of neutral polysaccharides with rabbit antisera to Microsporum quinckeanum, Trichophyton schoenleinii, Trichophyton rubrum, Trichophyton interdigitale, and Trichophyton granulosum.

The serological reactivities of polysaccharides isolated from five species of dermatophytes, Microsporum quinckeanum, Trichophyton granulosum, T. interdigitale, T. rubrum, and T. schoenleinii, with rabbit antisera to these species were studied qualitatively by precipitation in gel and quantitatively by complement-fixation analyses. Significant differences in the serological reactivities of the galactomannans I were detected with antisera to T. schoenleinii and T. interdigitale. The differences appeared to be related to the specificity of these antisera for the galactofuranose residues in the polysaccharides. Antisera to M. quinckeanum, T. granulosum, or T. rubrum did not detect differences between the galactomannans I. The serological reactivities of the galactomannans II were different with each of the five antisera. The reactivities of the glucans could be correlated with the amount of alpha 1 --> 6 linked glucopyranose residues when antisera to T. schoenleinii and M. quinckeanum were used.

Animals↗
PubMed1969

Immunological studies on dermatophytes. IV. Chemical structures and serological reactivities of polysaccharides from Microsporum praecox, Trichophyton ferrugineum, Trichophyton sabouraudii, and Trichophyton tonsurans.

The chemical structures and serological specificities of polysaccharides isolated from four species of dermatophytes, Microsporum praecox, Trichophyton ferrugineum, T. sabouraudii, and T. tonsurans, were investigated. Each of these species yielded a mixture of crude polysaccharides which could be separated into three water-soluble, neutral polysaccharides free of nitrogen. These were grouped as galactomannan I, galactomannan II, and glucan. The galactomannans I were quite similar in chemical structure. When measured by complement fixation, their serological cross-reactivities were similar with rabbit antisera to each of these species except T. sabouraudii. The differences in their relative reactivities with this antiserum could be correlated with differences in structure and specificity of this antiserum for galactofuranose end groups. The galactomannans II differed both in chemical structure and in their serological reactivities with antisera to each of these species. The galactomannan II from T. ferrugineum differed most in chemical structure and was the least reactive serologically. The glucans also differed in both structure and serological reactivities.

Antigens↗
PubMed2006

Specific primers for rapid detection of Microsporum audouinii by PCR in clinical samples.

This report describes application of PCR fingerprinting to identify common species of dermatophytes using the microsatellite primers M13, (GACA)4, and (GTG)5. The initial PCR analysis rendered a specific DNA fragment for Microsporum audouinii, which was cloned and sequenced. Based on the sequencing data of this fragment, forward (MA_1F) and reverse (MA_1R) primers were designed and verified by PCR to establish their reliability in the diagnosis of M. audouinii. These primers produced a singular PCR band of 431 bp specific only to strains and isolates of M. audouinii, based on a global test of 182 strains/isolates belonging to 11 species of dermatophytes. These findings indicate these primers are reliable for diagnostic purposes, and we recommend their use in laboratory analysis.

Adolescent↗
PubMed1982

Microsporum equinum in North America.

Microsporum equinum was isolated in Ontario, Canada, from five human and two equine cases of ringworm infection. This dermatophyte was previously recovered from North American horses on several occasions, but was considered to be M. canis. We regard M. equinum as distinct from M. canis. It can be differentiated from M. canis by the smaller size of its macroconidia, its failure to perforate hair in vitro, its poor growth and sporulation on bromocresol purple casein dextrose agar, and its incompatibility with Nannizzia otae, the telemorph of M. canis.

Animals↗
PubMed1985

Serological analysis of dermatophyte isolates with monoclonal antibodies produced against Microsporum canis.

Hybridoma cells produced by fusing myeloma cells with spleen cells from mice immunized with a soluble antigen of Microsporum canis yielded 30 antibody-producing clones. Six of these clones, propagated as ascites tumors in mice, showed two different types of monoclonal antibodies. The type 1 monoclonal antibody reacted with 17 heterologous and 10 homologous dermatophyte antigens. Type 2 monoclonal antibodies were unable to precipitate three antigens from different isolates of M. canis, thus suggesting the occurrence of different serotypes within the species.

Animals↗
PubMed1986

Identification and serotyping of Microsporum canis isolates by monoclonal antibodies.

Hybridoma cells were produced by fusing mouse myeloma cells with spleen cells from mice primed with an exoantigen of Microsporum canis. Three clones produced antibodies which were examined by the Western blot technique for their potential usefulness in the identification of M. canis isolates and differentiation of strains within the species. Based on reactions with immunological determinants, all of the M. canis isolates tested presented either species- or strain-specific domains. Monoclonal antibodies proved to be useful reagents for the identification of M. canis isolates and for the differentiation of strains within the species. A purified antigen depleted of common antigenic determinants was obtained in affinity chromatography by using monoclonal antibody.

Animals↗
PubMed1987

Improved procedures for differentiating Microsporum persicolor from Trichophyton mentagrophytes.

Microsporum persicolor, a zoophilic dermatophyte species, is seldom recorded causing human infections in North America. Its identification has been enhanced as a direct result of the development of improved techniques for its characterization. Identifying characteristics include induction of rough-walled macroconidia on sodium chloride-amended medium, absence of good growth at 37 degrees C, and absence of a pH change during growth on casein glucose medium. In contrast, Trichophyton mentagrophytes, a species commonly confused with M. persicolor, has smooth-walled macroconidia, grows well at 37 degrees C, and produces an alkaline reaction on casein glucose medium.

Culture Media↗
PubMed1988

Dermatophyte-hormone relationships: characterization of progesterone-binding specificity and growth inhibition in the genera Trichophyton and Microsporum.

We reported previously that Trichophyton mentagrophytes contains a cytoplasmic macromolecule which specifically binds progesterone. Progesterone is also an effective inhibitor of growth of the fungus. We report here studies which characterize more fully the specific binding properties and the functional responses of T. mentagrophytes and taxonomically related fungi to a series of mammalian steroid hormones. Scatchard analysis of [3H]progesterone binding in both the + and - mating types of Arthroderma benhamiae and in Microsporum canis revealed a single class of binding sites with approximately the same affinity as that in T. mentagrophytes (Kd, 1 X 10(-7) to 2 X 10(-7) M). Trichophyton rubrum had a protein with a higher binding affinity (Kd, 1.6 X 10(-8) M). Characterization of the [3H]progesterone-binding sites in T. mentagrophytes showed the binder to be a protein which was destroyed by trypsin and heating to 56 degrees C. Previous examination of the steroid-binding specificity in T. mentagrophytes had demonstrated that deoxycorticosterone (DOC) and dihydrotestosterone (DHT) were effective competitors for [3H]progesterone binding. Expansion of this study to include other competitors revealed that R5020 (a synthetic progestin), androstenedione, and dehydroepiandosterone possessed relative binding affinities which were 20, 11, and 9% of that of progesterone, respectively. Other ligands tested were less effective. Competition studies for the binder in M. canis resulted in similar findings: DOC and DHT were effective competitors for [3H]progesterone binding. The growth of A. benhamiae + and -, M. canis, and T. rubrum were all inhibited by progesterone in a dose-responsive manner, with 50% inhibition achieved at concentrations of 9.8 x 10(-6), 1.2 x 10(-5), 1.5 x 10(-5), and 2.7 x 10(-6) M. respectively,.

Binding, Competitive↗
PubMed1996

Primary invasive cutaneous Microsporum canis infections in immunocompromised patients.

Two cases of primary invasive cutaneous infections caused by the zoophilic dermatophytic species Microsporum canis are presented. The first case occurred in a liver transplant recipient who was receiving immunosuppressive therapy. Multiple erythematous papules were seen on both legs, and a biopsy revealed invasive fungal hyphae. The second case was diagnosed in a human immunodeficiency virus-positive individual with a CD4 lymphocyte count of 81 mm3. Raised red nodules were seen on her scalp and face. Histopathology was consistent with bacillary angiomatosis, and in addition, invasive septate hyphae were observed. The two strains recovered from the biopsy specimens from both individuals had colony morphologies consistent with that of M. canis, but it was difficult to induce production of macroconidia. These cases serve to increase the awareness of this unusual infection, reinforce the need for cultures, and raise some interesting questions about the potential virulence of this dermatophyte species.

AIDS-Related Opportunistic Infections↗
PubMed1999

Case of onychomycosis caused by Microsporum racemosum.

We report the case of a Spanish 60-year-old female who presented in 1997 with onychomycosis of the left thumbnail following an injury caused by a fresh fish bone. Microsporum racemosum was repeatedly cultured from nail scrapings, and its identity was confirmed by sequencing the isolate's ITS1/ITS2 and 5.8S rRNA regions. The patient was successfully treated with itraconazole, which was administered for 12 weeks. This represents the first case of onychomycosis due to M. racemosum and the first time that this species has been isolated from a human in Europe.

DNA, Fungal↗
PubMed1991

Disinfectants in the control of small animal ringworm due to Microsporum canis.

Twelve disinfectant products or compounds were evaluated for their ability to kill Microsporum canis harvested from naturally infected material. The disinfectants were diluted to the concentration recommended for the disinfection of clean surfaces and the potency of each substance was determined by the degree to which it could be further diluted before losing its fungicidal action. Hypochlorite, benzalkonium chloride and glutaraldehyde based compounds were the most effective agents and phenolics, alcohol and anionic detergents were inadequate. Urea (10 mM) did not adversely affect the potency of any of the compounds.

Animals↗