title: Differentiation of Candida parapsilosis, C. orthopsilosis, and C. metapsilosis by specific PCR amplification of the RPS0 intron.
abstract: Although Candida parapsilosis is the most prevalent among the 3 species of the *psilosis group, studies applying DNA-based diagnostic techniques with isolates previously identified as C. parapsilosis have revealed that both C. orthopsilosis and C. metapsilosis account for 0-10% of all these isolates, depending on the geographical area. Differences in the degrees of antifungal susceptibility and virulence have been found, so a more precise identification is required. In a first approach, we reidentified 38 randomly chosen clinical isolates, previously identified as C. parapsilosis, using the RPO2 (CA2) RAPD marker. Among them, we reclassified 4 as C. metapsilosis and 5 as C. orthopsilosis. We previously developed a method to identify different pathogen yeast species, including C. parapsilosis, based on the amplification of the RPS0 gene intron. In this work, we extend this approach to the new *psilosis species by partially sequencing their RPS0 gene, including the intron sequence. Based on intron sequences, we designed specific primers capable of identifying C. orthopsilosis and C. metapsilosis species, and we reidentified species among the initial isolates. These new primers have allowed a specific and rapid identification of C. orthopsilosis and C. metapsilosis.
authors.affiliation: GMCA Research Unit, Departamento de Microbiología y Ecología, Universidad de Valencia, Avda. Vicente Andrés Estellés s/n, 46100-Burjassot, Valencia, Spain.
authors.forename: M
authors.initials: M
authors.lastname: del Pilar Vercher
authors.forename: José M
authors.initials: JM
authors.lastname: García Martínez
authors.forename: Emilia
authors.initials: E
authors.lastname: Cantón
authors.forename: Javier
authors.initials: J
authors.lastname: Pemán
authors.forename: M Micaela
authors.initials: MM
authors.lastname: Gómez García
authors.forename: Eulogio Valentín
authors.initials: EV
authors.lastname: Gómez
authors.forename: Lucas
authors.initials: L
authors.lastname: del Castillo Agudo
mesh_terms: D000935:Antifungal Agents; D001483:Base Sequence; D002175:Candida / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D004271:DNA, Fungal / Q000235:genetics; D025141:Drug Resistance, Fungal; D005800:Genes, Fungal; D007438:Introns; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D016533:Mycological Typing Techniques; D016133:Polymerase Chain Reaction / Q000379:methods; D019105:Random Amplified Polymorphic DNA Technique; D017422:Sequence Analysis, DNA; D013045:Species Specificity
chemical_list: D000935:Antifungal Agents; D017931:DNA Primers; D004271:DNA, Fungal