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ABSTRACTIsolates of Paracoccidioides brasiliensisand Paracoccidioides lutzii, previously characterized by molecular techniques, were identified for the first time by matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS). All isolates were correctly identified, with log score values of >2.0. Thus, MALDI-TOF MS is a new tool for differentiating species of the genus Paracoccidioides.

ABSTRACTInteins are coding sequences that are transcribed and translated with flanking sequences and then are excised by an autocatalytic process. There are two types of inteins in fungi, mini-inteins and full-length inteins, both of which present a splicing domain containing well-conserved amino acid sequences. Full-length inteins also present a homing endonuclease domain that makes the intein a mobile genetic element. These parasitic genetic elements are located in highly conserved genes and may allow for the differentiation of closely related species of the Candida parapsilosis(psilosis) complex. The correct identification of the three psilosis complex species C. parapsilosis, Candida metapsilosis, and Candida orthopsilosisis very important in the clinical setting for improving antifungal therapy and patient care. In this work, we analyzed inteins that are present in the vacuolar ATPase gene VMAand in the threonyl-tRNA synthetase gene ThrRSin 85 strains of the Candidapsilosis complex (46 C. parapsilosis, 17 C. metapsilosis, and 22 C. orthopsilosis). Here, we describe an accessible and accurate technique based on a single PCR that is able to differentiate the psilosis complex based on the VMA intein. Although the ThrRS intein does not distinguish the three species of the psilosis complex by PCR product size, it can differentiate them by sequencing and phylogenetic analysis. Furthermore, this intein is unusually present as both mini- and full-length forms in C. orthopsilosis. Additional population studies should be performed to address whether this represents a common intraspecific variability or the presence of subspecies within C. orthopsilosis.

ABSTRACTParacoccidioides brasiliensisisolates from 10 nine-banded armadillos (Dasypus novemcinctus) were comparable with 19 clinical isolates by sequence analysis of the PbGP43gene and ribosomal internal transcribed spacer 1 (ITS1) and ITS2 and by random amplified polymorphic DNA. In this original ITS study, eight isolates differed by one or three sites among five total substitution sites.