In this study, we established an in-house database of yeast internal transcribed spacer (ITS) sequences. This database includes medically important as well as colonizing yeasts that frequently occur in the diagnostic laboratory. In a prospective study, we compared molecular identification with phenotypic identification by using the ID32C system (bioMérieux) for yeast strains that could not be identified by a combination of CHROMagar Candida and morphology on rice agar. In total, 113 yeast strains were included in the study. By sequence analysis, 98% of all strains were identified correctly to the species level. With the ID32C, 87% of all strains were identified correctly to the species or genus level, 7% of the isolates could not be identified, and 6% of the isolates were misidentified, most of them as Candida rugosa or Candida utilis. For a diagnostic algorithm, we suggest a three-step procedure which integrates morphological criteria, biochemical investigation, and sequence analysis of the ITS region.Yeast infections are increasing due to the growing number of immunocompromised and severely ill patients (5, 9). In addition, widespread use of antibiotics and invasive procedures facilitate infections with yeasts (18). Although Candida albicans is still the most frequently encountered yeast species, others have gained increasing importance in the last few years (1). Some species, such as Candida krusei (resistance to fluconazole) or Trichosporon sp. (reduced susceptibility to amphotericin B), may show inherent resistance to antimycotics (13). Rapid and accurate identification is thus essential for proper treatment. Various identification methods have been proposed in the past, including morphology, physiological properties, nucleic acid amplification, restriction fragment length polymorphism analysis, and sequencing (2).For molecular identification, we have chosen sequence analysis since this procedure is simple and can be fully automated. In addition, interpretation of nucleic acid sequences is straightforward and does not depend on too much expertise compared to morphological analyses. As target, we have chosen the internal transcribed spacer (ITS) region, which is located between the highly conserved genes coding for 18S and 28S rRNA. The ITS encompasses the two noncoding regions ITS1 and ITS2, which are separated by the highly conserved 5.8S rRNA gene (20). The ITS1 and ITS2 regions are more variable than the adjacent rRNA gene sequences and thus promise a better separation of closely related species. As the inspection of yeast ITS sequences which are available in the public database GenBank (NCBI) suggested that some entries are incorrect and because certain medically relevant species are not included, we decided to establish an in-house database. Since the number of known yeast species is enormous, we restricted our database to species occurring in the medical diagnostic laboratory.In this study, we compared sequence-based identification with conventional identification. Based on these results, we establish...

No abstract

No abstract

The data raised for Cryptococcus neoformans and cryptococcosis in Austria, Germany and Switzerland during the period from July 1997 to December 1999 are presented and analysed according to the epidemiological criteria. This is part of the ECMM survey in Europe.

We reported previously that Trichophyton mentagrophytes contains a cytoplasmic macromolecule which specifically binds progesterone. Progesterone is also an effective inhibitor of growth of the fungus. We report here studies which characterize more fully the specific binding properties and the functional responses of T. mentagrophytes and taxonomically related fungi to a series of mammalian steroid hormones. Scatchard analysis of [3H]progesterone binding in both the + andmating types of Arthroderma benhamiae and in Microsporum canis revealed a single class of binding sites with approximately the same affinity as that in T. mentagrophytes (Kd, 1 X 10-7 to 2 X 10-7 M). Trichophyton rubrum had a protein with a higher binding affinity (Kd, 1.6 x 10-8 M). Characterization of the [3H]progesterone-binding sites in T. mentagrophytes showed the binder to be a protein which was destroyed by trypsin and heating to 56°C. Previous examination of the steroid-binding specificity in T. mentagrophytes had demonstrated that deoxycorticosterone (DOC) and dihydrotestosterone (DHT) were effective competitors for [3H]progesterone binding. Expansion of this study to include other competitors revealed that R5020 (a synthetic progestin), androstenedione, and dehydroepiandosterone possessed relative binding aflinities which were 20, 11, and 9% of that of progesterone, respectively. Other ligands tested were less effective. Competition studies for the binder in M. canis resulted in similar findings: