Phenotypic and molecular identification of Fonsecaea pedrosoi strains isolated from chromoblastomycosis patients in Mexico and Venezuela.
Chromoblastomycosis is a chronic granulomatous disease caused frequently by fungi of the Fonsecaea genus. The objective of this study was the phenotypic and molecular identification of F. pedrosoi strains isolated from chromoblastomycosis patients in Mexico and Venezuela. Ten strains were included in this study. For phenotypic identification, we used macroscopic and microscopic morphologies, carbohydrate assimilation test, urea hydrolysis, cixcloheximide tolerance, proteolitic activity and the thermotolerance test. The antifungal activity of five drugs was evaluated against the isolates. Molecular identification was performed by sequencing the internal transcribed spacer (ITS) ribosomal DNA regions of the isolated strains. The physiological analysis and morphological features were variable and the precise identification was not possible. All isolates were susceptible to itraconazole, terbinafine, voriconazole and posaconazole. Amphotericin B was the least effective drug. The alignment of the 559-nucleotide ITS sequences from our strains compared with sequences of GenBank revealed high homology with F. pedrosoi (EU285266.1). In this study, all patients were from rural areas, six from Mexico and four from Venezuela. Ten isolates were identified by phenotypic and molecular analysis, using ITS sequence and demonstrated that nine isolates from Mexico and Venezuela were 100% homologous and one isolate showed a small genetic distance.
División Ciencias de la Salud, Departamento de Ciencias Básicas, Universidad de Monterrey, San Pedro Garza García, Nuevo León, México; Departamento de Microbiología, Facultad de Medicina, Universidad Autónoma de Nuevo León, Monterrey, Nuevo León, México.
O
O
Carolina Rojas
Rafael B R
RB
León-Cachón
Antonio Alí
AA
Pérez-Maya
Marcelino
M
Aguirre-Garza
María G
MG
Moreno-Treviño
Gloria M
GM
González
D000328:Adult; D000368:Aged; D000666:Amphotericin B / Q000494:pharmacology; D000935:Antifungal Agents / Q000494:pharmacology / Q000627:therapeutic use; D001203:Ascomycota / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D002862:Chromoblastomycosis / Q000188:drug therapy / Q000382:microbiology*; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D005260:Female; D006801:Humans; D017964:Itraconazole / Q000494:pharmacology; D008297:Male; D008800:Mexico; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D003904:Mitosporic Fungi / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D008969:Molecular Sequence Data; D010641:Phenotype; D017422:Sequence Analysis, DNA; D012867:Skin / Q000382:microbiology*; D014687:Venezuela; D065819:Voriconazole / Q000494:pharmacology
D000935:Antifungal Agents; D021903:DNA, Ribosomal Spacer; D017964:Itraconazole; D000666:Amphotericin B; D065819:Voriconazole
Fonsecaea pedrosoi; ITS; chromoblastomycosis; molecular identification; phenotypic characteristics