NUCLEOTIDE-SEQUENCE ANALYSIS OF A VARIABLE REGION OF THE LARGE SUBUNIT RIBOSOMAL-RNA FOR IDENTIFICATION OF MARINE-OCCURRING YEASTS

A 230-nucleotide region of the large subunit (LSU) ribosomal RNA was examined to determine whether signature nucleotide sequences could be used for species identifications of basidiomycetous yeasts. Multiple strains of genetically defined heterothallic species of Rhodosporidium, Leucosporidium, Cystofilobasidium, and Sporidiobolus demonstrated that nucleotide sequences within these species are homologous and that differences between species range from 1 to 20 or more bases. Also included in this study were several homothallic species of these teleomorphic genera and some anamorphs assigned to Rhodotorula and Candida. Those results indicated close relationships among certain homothallic species, particularly in the genus Mrakia, and potential relationships of homothallic and anamorphic strains to several teleomorphs. The data suggest that LSU sequences can be used for yeast identifications with the possible exception of closely related homothallic species.