COENZYME Q SYSTEM IN THE CLASSIFICATION OF THE ASCOSPOROGENOUS YEAST GENERA HANSENULA AND PIGHIA

摘要

From the cells of 128 strains which belong to the genera Hansenula, Pichia, Citeromyces, Pachysolen, and Wingea, coenzyme Q (Co-Q) was extracted and partially purified. The type of Co-Q was determined mainly by paper chromatography. The Co-Q system of the genus Hansenula was composed of Co-Q7 except for two species, H. capsulate (Q8) and H. holstii (Q8). Others with the latter unique quinone system were Cit. matritensis and Pa. tannophilus. In contrast, the heterogeneous nature of the genus Pichia was reconfirmed, because of a complex distribution of three different kinds of Co-Q (Q7, Q8, and Q9). Most species of this genus with hat- or Saturn-shaped ascospores such as P. membranaefaciens were characterized by possessing Co-Q7, whose Co-Q system was consistent with that of the genus Hansenula. Pichia pastoris was the only species with Co-Q8 in this genus. The Co-Q9 system was found in P. farinosa, P. haplophila, all of "round-spored" pichiae, some of the guilliermondii group and W. robertsii. The results concerning the Co-Q system are discussed in connection with other criteria such as serological characteristics, PMR spectra of cell-wall mannans, DNA base composition, etc.