- Volume 31, Issue 3, 1981

The genus Holospora was named and described by Hafkine in 1890 for bacteria which inhabit the nuclei of paramecia. Because holosporas could not be cultivated, the name Holospora and the names of the species in the genus were not included in the Approved Lists of Bacterial Names (Skerman et al., ed., Int. J. Syst. Bacteriol. 30:225-420, 1980). Recently, we examined organisms identified as belonging to two Holospora species, “Holospora undulata” Hafkine 1890 and “Holospora obtusa” Hafkine 1890 and confirmed the descriptions of Hafkine. In the past, some workers have considered these organisms to be hereditary factors or particles, referred to as omega and iota particles. This practice should be abandoned, and the organisms should be referred to by their proper scientific names. Consequently, the names Holospora, H. undulata (the type species), and H. obtusa are revived here for the same organisms to which the names were originally applied by Hafkine. Because these organisms have not been cultivated, the illustrations and descriptions of these organisms serve as representatives of their nomenclatural types.

We used polyacrylamide slab gel electrophoresis with specific staining for seven enzymes to compare 108 strains belonging to the genera Rhodotorula and Rhodosporidium. The patterns obtained allowed us to divide the strains of Rhodotorula glutinis and its varieties into six groups. The strains of Rhodotorula rubra and Rhodotorula pilimanae examined had identical patterns. Rhodotorula minuta var. minuta and Rhodotorula minuta var. texensis clearly differed from Rhodotorula glutinis and Rhodotorula rubra in their hexokinase and 6-phosphogluconate dehydrogenase patterns. Rhodotorula marina, Rhodotorula pallida, and Rhodotorula lactosa each had a characteristic pattern. We found three haploid mating type strains to mating type a of Rhodosporidium toruloides, mating type a of Rhodosporidium sphaerocarpum, and mating type a of Rhodosporidium diobovatum among the strains of Rhodotorula glutinis var. rufusa, Rhodotorula glutinis var. salinaria, and Rhodotorula glutinis var. glutinis by performing conjugation tests to confirm the relationships that were revealed when the enzyme patterns were compared. In the genus Rhodosporidium, compatible mating type strains showed similar enzymatic patterns. Strains of Rhodosporidium toruloides which could not assimilate potassium nitrate had the same enzymatic patterns as those that could.