Lehmann PF, Zeng S; American Society for Microbiology. General Meeting.
Abstr Gen Meet Am Soc Microbiol. 1997 May 4-8; 97: 262 (abstract no. F13).
Medical College of Ohio, Toledo, OH.
Several clinically-relevant yeasts can be shown to represent species complexes when examined by use of simple molecular genetic methods, such as by use of isoenzyme and random amplified polymorphic DNA (RAPD) analysis. Such species complexes include the Candida parapsilosis complex, the C. guilliermondii - C. fermentati - C. guilliermondii var. carpophila - ATCC 22949 complex, and the C. albicans - C. dubliniensis complex. Because simple morphological and physiological phenotypes may not be readily discovered that differentiate the different species within a complex, taxonomic schemes based on genetic characteristics are required. RAPD patterns were found to show a limited amount of lane to lane variation, even when the analysis was made on PCR products of a single preparation that was subdivided into several tubes prior to being placed in a thermocycler. Such variation was not due to inadequate mixing or annealing times, though changes in the latter affected the complexity of the RAPD patterns. The variations may result from a certain degree of chaos associated with the annealing of short primers, and increase the difficulty of discriminating distinct strains unless many PCRs are performed. In contrast to the problem of using RAPD patterns to delineate strains within a species, substantial differences in the patterns are detected when different species are compared. Sequence differences within the DNA encoding the 5.8 S rRNA and adjacent internally transcribed sequences show a direct correlation with differences in isoenzyme and RAPD profiles obtained for isolates within the C. guilliermondii and C. parapsilosis complexes. Therefore, different clinical isolates representing these species complexes may best be identified by molecular-genetic analysis. Protocols involving either isoenzyme or RAPD analysis appear adequate for this purpose.
Publication Types:
Keywords:
- Animals
- Base Sequence
- Candida
- Candidiasis
- Fungemia
- Humans
- Infection
- Opportunistic Infections
- Phenotype
- Polymerase Chain Reaction
- Random Amplified Polymorphic DNA Technique
- genetics
Other ID:
UI: 102235326
From Meeting Abstracts