A comparison of methods of phenotypic and genotypic fingerprinting of Exophiala dermatitidis isolated from sputum samples of patients with cystic fibrosis.
Phenotypic and genotypic characteristics of 11 strains of Exophiala dermatitidis were investigated. Ten strains (including three reference strains) were isolated from sputum samples of six patients with cystic fibrosis (CF) in Germany, and one reference strain was isolated from a patient with phaeohyphomycosis in Japan. The strains showed differences in their ability to assimilate sorbitol, palatinose, rhamnose, gluconate and melezitose, leading to the differentiation of seven auxotypes. The IC30 of amphotericin B, and ketoconazole and itraconazole, respectively, indicated susceptibility, whereas the IC30 of fluconazole and 5-fluorocytosine indicated resistance in all strains. Protein patterns in SDS-PAGE revealed no major differences. The glycoconjugate patterns distinguished the Japanese strain from the other strains. Cluster analysis of whole-cell fatty acid methyl ester (FAME) profiles with the Microbial Identification System (MIS) revealed two major clusters separating a reference strain and the Japanese strain from the other strains. Analysis of patterns resulting from random amplification of polymorphic DNA (RAPD) with two arbitrary primers showed four genotypes. Comparison of the results revealed no agreement between the different fingerprinting methods, except the separation of the Japanese strain from the European CF strains. As the results of assimilation tests seem to vary between different laboratories, the analysis of FAME profiles and RAPD analysis are recommended for typing E. dermatitidis.
Rath
P M
PM
Institut für Medizinische Mikrobiologie. Universität-GH Essen, Germany.
Müller
K D
KD
Dermoumi
H
H
Ansorg
R
R
D000935:Antifungal Agents / Q000494:pharmacology; D050260:Carbohydrate Metabolism; D016000:Cluster Analysis; D003550:Cystic Fibrosis / Q000382:microbiology*; D004271:DNA, Fungal / Q000032:analysis; D004952:Esters; D005093:Exophiala / Q000145:classification* / Q000302:isolation & purification / Q000502:physiology; D005227:Fatty Acids / Q000032:analysis; D005656:Fungal Proteins / Q000032:analysis; D005838:Genotype; D006001:Glycoconjugates / Q000032:analysis; D006801:Humans; D008826:Microbial Sensitivity Tests; D016533:Mycological Typing Techniques; D010641:Phenotype; D019105:Random Amplified Polymorphic DNA Technique; D013183:Sputum / Q000382:microbiology*
D000935:Antifungal Agents; D004271:DNA, Fungal; D004952:Esters; D005227:Fatty Acids; D005656:Fungal Proteins; D006001:Glycoconjugates