The phylogenetic relationships of Pichia jadinii, formerly classified in the genus Hansenula, and related species based on the partial sequences of 18S and 26S ribosomal RNAs (Saccharomycetaceae).

We analyzed 18S and 26S rRNA partial base sequences [positions 1451-1618 (168 bases) of 18S rRNA and positions 1611-1835 (225 bases) and 493-622 (130 bases) of 26S rRNA] of a total of three strains of Pichia jadinii and Candida utilis. The three strains had identical base sequences with the type strain of P. jadinii (IFO 0987) in the 18S rRNA partial base sequencings. In the 26S rRNA partial base sequencings, there were partial base sequences similar to each other (1-0 base difference and 87-95 percent similarities). The sequence data obtained are discussed taxonomically and phylogenetically, especially in connection with Williopsis saturnus, the type species of the genus Williopsis Zender.