Molecular subtyping of clinical and environmental strains of Cryptococcus neoformans variety neoformans serotype A isolated from southern Italy

• Published in: Mycoses 1998-03, Vol.41 (3-4), p.117-124
• Main Authors: Pernice, Ida, Passo, Carla Lo, Criseo, G., Pernice, A., Todaro-Luck, Flora
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Cryptococcosis - epidemiology; Cryptococcosis - microbiology; Cryptococcus neoformans; Cryptococcus neoformans - classification; Cryptococcus neoformans - genetics; Cryptococcus neoformans neoformans; DNA Fingerprinting; DNA, Fungal; DNA, Ribosomal; Environmental Microbiology; Human mycoses; Humans; Infectious diseases; Italy; Medical sciences; Miscellaneous mycoses; Molecular Epidemiology - methods; molecular typing; molekulare Typisierung; Mycoses; Polymorphism, Restriction Fragment Length; Random Amplified Polymorphic DNA Technique; RAPD; RFLP; Serotyping
• ISSN: 0933-7407; 1439-0507
• DOI: 10.1111/j.1439-0507.1998.tb00312.x

Analysis of ribosomal DNA (rDNA) restriction fragment‐length polymorphism (RFLP) and random amplification of polymorphic DNA (RAPD) was used to investigate the genetic variability and biogeographic distribution of clinical and environmental strains of Cryptococcus neoformans isolated from a limited area of southern Italy, where the selection of a predomimant cryptococcal genotype could be expected. All isolates belonged to the species Cr. neoformans variety neoformans serotype A. RFLP analysis of a specific rDNA fragment allowed the distinction of strains of Cr. neoformans from closely related fungal reference species, but neither intraspecies nor intravarieties polymorphism was detected. On the contrary, RAPD fingerprints produced by priming with four different primers [(GTG)5, (GACA)4, M13 core sequence and the 8‐mer oligonucleotide (GCG‐GACGG)] were able to characterize the isolates up to the individual level, indicating the presence of marked heterogeneity among Cr. neoformans serotype A strains in southern Italy. Zusammenfassung Es wurde die genetische Variabilität von klinischen und Umgebungs‐isolaten von Cryptococcus neoformans untersucht, die aus einer isolierten Region Süditaliens stammten, wo die Selektion eines prädominierenden Cr. neoformans‐Genotyps denkbar wäre. Alle Isolate waren Cr. neoformans var. neoformans Serotyp A. Zur Untersuchung wurde ribosomale DNA mittels RFLP und RAPD analysiert. Die RFLP‐Analyse erlaubte die Unterscheidung von Cr. neoformans von anderen Pilzarten, deckte jedoch keine Intraspecies‐ oder Intravarietät‐Polymorphismen auf. RAPD‐Fingerprints ermöglichten jedoch die Charakterisierung individueller Isolate und belegten eine bemerkens‐werte genetische Heterogenität der Cr. neoformans‐Stämme des Serotyps A in Süditalien.