DNA relatedness, karyotyping and gene probing of Candida tropicalis, Candida albicans and its synonyms Candida stellatoidea and Candida Claussenii

Mahrous, Mona; Sawant, A D; Pruitt, W. R.; Lott, Timothy J.; Meyer, Sally A.; Ahearn, Donald G.

doi:10.1007/bf00158581

Cited by 10 publications

(9 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1 and in detail in Table 2. Candida stellatoidea is regarded as a synonym of C. albicans, since these two species cannot be discriminated from each other by the ITS sequence (10). Candida africana is included as a separate species, although it is difficult to discriminate from C. albicans with an interspecies sequence homology of 99.3 to 99.8%, which is almost identical to the intraspecies homology of C. albicans (99.3 to 100.0%).…”

Section: Resultsmentioning

confidence: 99%

Internal Transcribed Spacer Sequencing versus Biochemical Profiling for Identification of Medically Important Yeasts

et al. 2006

View full text Add to dashboard Cite

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...

show abstract

Section: Resultsmentioning

confidence: 99%

Internal Transcribed Spacer Sequencing versus Biochemical Profiling for Identification of Medically Important Yeasts

et al. 2006

View full text Add to dashboard Cite

show abstract

“…In fact, PFGE has been employed mainly to highlight inter-and intraspecies differences. A PFGE variant, contour-clamped gel electrophoresis (CHEF) is considered the best approach for strain differentiation [16,17]. However, extensive PFGE studies on various micro-organisms have not been completely satisfactory because of lack of standardisation of methods and this has produced con¯icting results in different laboratories [14±17].…”

Section: Introductionmentioning

confidence: 99%

Heterogeneity of oral isolates of Candida albicans in HIV-positive patients: correlation between candidal carriage, karyotype and disease stage

Capoluongo¹,

Moretto

Giglio

et al. 2000

Journal of Medical Microbiology

View full text Add to dashboard Cite

Opportunist infections involving Candida albicans often develop in HIV-positive patients and oral lesions tend to become more frequent as the disease progresses. Previous studies have shown contrasting results concerning the variability of the pulsed-®eld gel electrophoresis (PFGE) subtypes of C. albicans observed in HIV-positive patients. Carriage of C. albicans was determined by an oral rinse technique; 41 strains of C. albicans (78% serotype A and 22% serotype B) were isolated. There was a direct correlation between candidal load (cfu/ml) and the blood HIV load, whereas there was an inverse correlation with the stage of disease and the CD4 cell counts. The PFGE patterns of isolates were variable with regard to the number and positions of bands. The variability of the band sizes in some run positions showed a Gaussian distribution. Generally, the most frequent size variants were associated with the strains with the highest cfu/ml and lowest CD4 counts (<200 cells/ìl). These ®ndings suggest a possible strain selection over time during disease progression, especially in HIV-positive subjects with low CD4 counts.

show abstract

“…presently treated as synonyms of C albicans [7,8,9,[11][12][13][14]. By using DNA reassociation techniques, Meyer [8] found a significant degree of DNA relatedness between the type strains of C albicans, C stellatoidea (sucrose negative), C claussenii (germ tube negative) and C langeronii (chlamydospore deficient) and recommended that these species be reduced to synonymy.…”

Section: Introductionmentioning

confidence: 99%

“…fermentation and assimilation of various substrates), plus various morphological characteristics. It is clear that variation in biochemical and morphological features can occur among members of a species, that is sometimes raanifested by a loss of one or a few characteristics which are viewed as typical for the species [6][7][8][9]. The genus Candida has been frequently revised with respect to the composition of its members, and numerous species have been reclassified as synonyms [10].…”

Section: Introductionmentioning

confidence: 99%

Atypical strains ofCandida albicansrecovered from AIDS patients

Pujol¹,

Renaud

Mallié

et al. 1997

Med Mycol

View full text Add to dashboard Cite

By using multilocus enzyme electrophoresis (MLEE) we have analyzed the genetic diversity encountered among chlamydospore-positive Candida albicans strains. While the type II strains of the former C. stellatoidea were genetically indistinguishable from those of C. albicans, type I strains constituted a distinct subgroup compared with C. albicans strains. Nevertheless, all these strains remained genetically very closely related compared with other species of Candida (e.g.C. tropicalis, C. krusei and C. glabrata). These results corroborate the synonymy between C. stellatoidea and C. albicans. Chlamydospore-positive C. albicans strains with atypical sugar assimilation patterns displayed a great genetic divergence from the cluster constituted by C. albicans and the strains of the former C. stellatoidea. However, these atypical strains were more closely related to C. albicans than they were to C. tropicalis, C. krusei or C. glabrata. These strains represent a genetically entity distinct from the typical C. albicans strains used in this study. The data also support the view that the atypical strains described here belong to the same genetic group as atypical C. albicans strains previously described by others.

show abstract

DNA relatedness, karyotyping and gene probing of Candida tropicalis, Candida albicans and its synonyms Candida stellatoidea and Candida Claussenii

Cited by 10 publications

References 37 publications

Internal Transcribed Spacer Sequencing versus Biochemical Profiling for Identification of Medically Important Yeasts

Internal Transcribed Spacer Sequencing versus Biochemical Profiling for Identification of Medically Important Yeasts

Heterogeneity of oral isolates of Candida albicans in HIV-positive patients: correlation between candidal carriage, karyotype and disease stage

Atypical strains ofCandida albicansrecovered from AIDS patients

Contact Info

Product

Resources

About