ISOENZYME, RESTRICTION-FRAGMENT-LENGTH-POLYMORPHISM, AND RANDOM AMPLIFIED POLYMORPHIC DNA CHARACTERIZATION OF PHAFFIA-RHODOZYMA MILLER ET-AL

The validity of the species concept was examined with strains of Phaff ia rhodozyma by comparing the isoenzyme profiles, ribosomal DNAs, and random amplified polymorphic DNA (RAPD) patterns of the strains. The i soenzyme profiles appeared to be more stable than the RAPD patterns or the electrophoretic karyotypes determined previously (G. Nagy, N. Gar amszegi, C. Vagvolgyi, and L. Ferenczy, FEMS Microbiol. Lett., in pres s). The ribosomal DNA patterns revealed only a limited degree of varia bility, while RAPD analysis proved to be the most useful method for di fferentiating the strains studied. Strain CBS 5905(T) (T = type strain ) produced characteristic RAPD patterns, which were different from tho se produced by the other strains. However, despite the high degree of variability observed, the isoenzyme data and the slightly variable rib osomal DNA hybridization profiles confirmed that the strains which we examined belong to one species.