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PubMed1986

The relationship of Phialophora verrucosa to Phialophora americana.

Phialophora verrucosa and P. americana, two dematiaceous hyphomycetes, are known to cause chromoblastomycosis. Even though most medical mycologists consider P. americana as synonymous with P. verrucosa, others maintain them as two distinct species on the basis that the phialides of P. americana have deeper collarettes than those of P. verrucosa. Thirty-two isolates, identified either as P. americana or P. verrucosa, were studied for their morphologic, physiologic, and antigenic characteristics to evaluate their taxonomic status. Collarette morphology was found to be a variable character in 12 of the 32 isolates. Those 12 produced phialides with both shallow and deep collarettes. All of the isolates hydrolysed urea within 7 days at 25 degrees C, and failed to liquefy gelatin after 3 weeks at 25 degrees C. None of the isolates decomposed casein, xanthine, or hypoxanthine at the end of 3 weeks at 25 degrees C. All decomposed tyrosine. They grew at 25 degrees C and 37 degrees C, but failed to grow at 40 degrees C. The antigenic relationship between the two species was studied by the exoantigen procedure. The 32 isolates showed close antigenic relatedness. Adsorptions of antisera with homologous and heterologous antigens rendered the antisera free of precipitin bands when studied by the microimmunodiffusion test. The depth of phialide collarettes produced by the two species, being found to be variable character, and the identical nature of the two species with respect to their physiologic and antigenic characteristics, led us to conclude that P. americana should be considered as a synonym of P. verrucosa.

Antigens, Fungal↗
PubMed1995

Comparison of fungi within the Gaeumannomyces-Phialophora complex by analysis of ribosomal DNA sequences.

Four ascomycete species of the genus Gaeumannomyces infect roots of monocotyledons. Gaeumannomyces graminis contains four varieties, var. tritici, var. avenae, var. graminis, and var. maydis. G. graminis varieties tritici, avenae, and graminis have Phialophora-like anamorphs and, together with the other Gaeumannomyces and Phialophora species found on cereal roots, constitute the Gaeumannomyces-Phialophora complex. Relatedness of a number of Gaeumannomyces and Phialophora isolates was assessed by comparison of DNA sequences of the 18S rRNA gene, the 5.8S rRNA gene, and the internal transcribed spacers (ITS). G. graminis var. tritici, G. graminis var. avenae, and G. graminis var. graminis isolates can be distinguished from each other by nucleotide sequence differences in the ITS regions. The G. graminis var. tritici isolates can be further subdivided into R and N isolates (correlating with ability [R] or inability [N] to infect rye). Phylogenetic analysis of the ITS regions of several oat-infecting G. graminis var. tritici isolates suggests that these isolates are actually more closely related to G. graminis var. avenae. The isolates of Magnaporthe grisea included in the analysis showed a surprising degree of relatedness to members of the Gaeumannomyces-Phialophora complex. G. graminis variety-specific oligonucleotide primers were used in PCRs to amplify DNA from cereal seedlings infected with G. graminis var. tritici or G. graminis var. avenae, and these should be valuable for sensitive detection of pathogenic isolates and for diagnosis of take-all.

Ascomycota↗
PubMed1997

Phialophora verrucosa infection in a BMT patient.

Phialophora is a dematiaceous fungus isolated from soil and wood. Human infections including chromoblastomycosis, mycotic keratitis, cutaneous infections, and prosthetic valve endocarditis have been reported. We report a case of fatal hemorrhage due to Phialophora verrucosa in a patient with prolonged neutropenia undergoing autologous bone marrow transplant (BMT) for acute myelogenous leukemia (AML). Bacterial infections complicated induction and consolidation chemotherapies. Liposomal amphotericin B (LAMB) was given from day +33 to day +72 for febrile neutropenia. Death occurred on day +74 due to tracheal hemorrhage. Autopsy revealed granulation tissue on the posterior wall of the trachea with fungal hyphae on histopathology; the tissue grew Phialophora verrucosa. In vitro susceptibility studies revealed a minimum inhibitory concentration to AmB of 0.1 microg/ml. This represents the first reported case of invasive P. verrucosa in a BMT patient leading to fatal hemorrhage, despite large cumulative doses of LAMB to which the organism remained susceptible.

Adult↗
PubMed1986

Exoantigen test for Cladosporium bantianum, Fonsecaea pedrosoi, and Phialophora verrucosa.

Exoantigens from 10-day-old cultures of 100 isolates of pathogenic and saprophytic dematiaceous fungi were analyzed by the exoantigen test. Antisera to Cladosporium bantianum ATCC 10958, Fonsecaea pedrosoi CDC AMO-B06, and Phialophora verrucosa CDC AMO-C12 were prepared in New Zealand rabbits immunized with soluble antigens from 1-month-old cultures. Absorbed and nonabsorbed antisera and exoantigens from the same organisms were used as reference reagents. Serologic reactions were analyzed in terms of the presence or absence of lines of identity or nonidentity. These reactions allowed presumptive differentiation of C. bantianum, F. pedrosoi, and Phialophora verrucosa from other dematiaceous fungi, including Cladosporium spp. (28 isolates), Exophiala spp. (18 isolates), Fonsecaea spp. (17 isolates). Lecythophora hoffmannii (4 isolates), Phaeoannellomyces werneckii (3 isolates), Phialophora spp. (17 isolates), Wangiella dermatitidis (9 isolates), and Rhinocladiella spp. (4 isolates).

Animals↗
PubMed1984

Phialophora parasitica, an emerging pathogen.

Monoconidial cultures derived from 12 clinical and environmental isolates of Phialophora parasitica were compared with respect to morphologic and physiologic characteristics and response to antifungal agents. No yeast cells were seen in 1- and 3-week-old slide culture preparations. Also, not all of the distinguishing characteristics of this species were displayed by all isolates on all media examined. Although the isolates grew on Sabouraud agar with chloramphenicol and cycloheximide, some inhibition was observed. All cultures were strongly urease-positive and hydrolyzed casein and starch; most decomposed tyrosine but not gelatin. All but one environmental isolate grew well at both 23 and 37 degrees C, but none grew at 40 degrees C. In the sensitivity testing the isolates did not vary much in their response to each drug, although some anomalies were observed. Amphotericin B and miconazole had minimum inhibitory concentrations in the low sensitivity range (2.0-8.0 and 2.5-10 micrograms m-1 respectively), for most isolates, and most isolates were resistant to both 5-fluorocytosine and ketoconazole. Limited observations were made on three other Phialophora species which might be confused with P. parasitica.

Amphotericin B↗
PubMed1975

Phialophora mutabilis endocarditis.

This is the first reported case of fungal endocarditis due to vegetative growth of Phialophora mutabilis on a prosthetic mitral valve. The patient had rheumatic heart disease with mitral and aortic stenosis. Four months after the mitral and aortic valves had been replaced by prostheses the patient developed congestive failure. Because of increased left atrial pressure, the mitral prosthesis was replaced. A large matted obstructive fungal vegetation was found on the prosthesis. Culture of this vegetation grew Phialophora mutabilis. The patient died postoperatively, and at autopsy the fungus was not found in other tissues. Culturally and morphologically, P. mutabilis shows wide variation in pigmentation, colonial and microscopic appearance. Conidia formation from intercalary cells along the hyphae is somewhat similar to that of Aureobasidium spp. P. mutabilis was injected into mice. Mice pretreated with cortisone died 3 to 5 weeks after intraperitoneal inoculation, while the majority of untreated mice died within 20 weeks of inoculation.

Animals↗
PubMedDate not supplied

Phialophora verrucosa infection in an AIDS patient.

Phialophora verrucosa is one of several pathogenic dematiaceous fungi associated with chromomycosis and occasionally phaeohyphomycosis. Infection appears to be increasing in frequency in both immunocompromised and presumably healthy patients. Medical therapy is often difficult, and a wide variety of antifungal agents have been tried with varying degrees of success. We report a patient with acquired immunodeficiency syndrome (AIDS) and extensive cutaneous fungal infection due to Phialophora verrucosa. The disease failed to respond to ketoconazole, but regression of the lesions was obtained with itraconazole.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Mitochondrial DNA analysis of Phialophora verrucosa.

Restriction fragment length polymorphism (RFLP) of mitochondrial DNA (mtDNA) was examined in 32 isolates of Phialophora verrucosa (eight isolates from Japan, 10 from China, four from the USA, six from Venezuela and four from Colombia) and in three of Phialophora americana using five restriction enzymes. P. verrucosa isolates were divided into 10 mtDNA types based on RFLP patterns. Phylogeny constructed on sequence divergence of mtDNA indicated that P. verrucosa is a single species and isolates are clustered into three groups. Japan and the USA contained Group A and Group B isolates, China Group B isolates and South America Group B and Group C isolates. RFLP patterns of P. americana mtDNA were identical to those of Type 1 or Type 4 of P. verrucosa mtDNA, suggesting that both are identical. RFLP patterns of P. verrucosa were distinct from those of other dematiaceous fungi including Exophiala jeanselmei, E. moniliae, E. dermatitidis, E. spinifera, Cladophialophora (Cladosporium) carrionii, Fonsecaea pedrosoi, and Hortaea werneckii. These results indicate that RFLP analysis of mtDNA is a useful method for the identification, taxonomy, typing, epidemiology and phylogeny of P. verrucosa.

DNA, Fungal↗
PubMed1976

Corneal chromomycosis: double infection by Phialophora verrucosa (Medlar) and Cladosporium cladosporioides (Frescenius).

Phialophora verrucosa and Cladosporium cladosporioides were isolated from a corneal ulcer. The lesion had been previously treated with antivirals and steroids and did not respond to Pimaricin therapy or conjunctival flap. A penetrating keratoplasty was performed with good functional and optical results. Chromomycosis of the cornea is an unusual infection. This is the second case of Phialophora in Florida and the first case of Cladosporium infection.

Animals↗
PubMed2002

Case report. Phaeohyphomycosis caused by Phialophora verrucosa developed in a patient with non-HIV acquired immunodeficiency syndrome.

A 53-year-old woman had asymptomatic multiple nodules on her gluteal region for 6 months. She had a history of systemic corticosteroid treatment for Evans' syndrome. Recently she had developed an immunodeficiency condition with CD4+ cell depletion without an HIV infection and a normal serum gamma globulin level. A smear from the purulent exudate of the nodules revealed many brown-coloured hyphae, spores and few large dark-brown cells. A short, hairy, dark-brown coloured colony was cultivated on Sabouraud glucose agar. Slide culturing revealed only a Phialophora-type conidia formation, and the fungus was diagnosed as Phialophora verrucosa. Severe immunosuppressive condition (non-HIV acquired immunodeficiency syndrome) of this patients after systemic corticosteroid treatment for Evans' syndrome predisposed an opportunistic cutaneous fungal infection due to P. verrucosa. Cases with cutaneous infection due to P. verrucosa reported in Japan are summarized and discussed.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Use of the polymerase chain reaction to identify coding sequences for chitin synthase isozymes in Phialophora verrucosa.

Based on conserved amino-acid regions predicted for the chitin synthases (Chs) of Saccharomyces cerevisiae, two different primer sets were synthesized and used in polymerase chain reactions (PCRs) to amplify 614-bp and 366-bp sequences from genomic DNA of the zoopathogenic fungus Phialophora verrucosa. DNA-sequencing and Southern-blotting analyses of the 614-bp DNA amplification products suggested that portions of two distinct P. verrucosa chitin synthase genes (PvCHS1, PvCHS2), coding for two different zymogenic-type PvChs isozymes, had been identified. The deduced amino-acid sequence of each fell into different Chs classes, namely class I and class II. In addition, the 366-bp DNA segment was shown to code for a conserved region having homology with the CSD2/CAL1 gene of S. cerevisiae, which encodes a nonzymogenic-type enzyme, Chs3, in that fungus. The amino-acid sequence derived from PvCHS3 exhibits 88.2% similarity and 78.4% identity to the same amino-acid region of the S. cerevisiae enzyme. These results provide a critical first step toward investigating the molecular and pathogenic importance of CHS gene regulation in this fungus and for exploring steps leading to Chs function as potential targets for the design of new therapeutic agents.

Amino Acid Sequence↗
PubMed1989

Lipases of Fonsecaea pedrosoi and Phialophora verrucosa.

Lipase activity was demonstrable titrimetrically in the culture filtrates of Fonsecaea pedrosoi and Phialophora verrucosa on the 6th day of incubation reaching a peak on the 15th and 12th days respectively for the two fungi. Purified lipases of F. pedrosoi and P. verrucosa, with specific activities of 36.0 and 39.4 fold increase respectively, were obtained by cold acetone extraction, gel filtration followed by ion exchange chromatography. The lipases had the same optimum pH (5.5) and temperature (35 degrees C). The molecular weights of the lipases of F. pedrosoi and P. verrucosa, estimated by gel filtration on Sephadex G-100, were 25,000 and 20,000, respectively and the enzymes showed broad substrate specificity. The possible role of lipase in the pathogenesis of infection caused by the fungi is discussed.

Electrophoresis, Disc↗