Submitted to: International Journal of Systematic and Evolutionary Microbiology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/28/2004
Publication Date: 3/15/2005
Citation: Kurtzman, C.P. 2005. Description of Komagataella phaffii sp. nov. and transfer of Pichia pseudopastoris to the methylotrophic yeast genus Komagataella. International Journal of Systematic and Evolutionary Microbiology. 55:973-976. Interpretive Summary: The methanol assimilating yeast Komagataella (Pichia) pastoris is widely used to produce enzymes and other proteins, such as human growth hormones, by recombinant DNA technology. The present study describes the new yeast Komagataella phaffii, which is closely related to K. pastoris, thus providing another species for biotechnological research. In this study, which is based on gene sequence analysis, the previously described Pichia pseudopastoris is transferred to Komagatella resulting in the genus now being phylogenetically defined. A practical result is that the three species now placed in this genus can be rapidly detected using a genus-specific DNA probe, and any yet to be discovered species of this genus should be detected with the probe.
Technical Abstract: The new methanol assimilating yeast species Komagataella phaffii Kurtzman sp. nov. (Type strain, NRRL Y-7556T, CBS 2612T) is described. Of the four known strains of this species, two were isolated from black oak trees in California and two are from unidentified sources. The species forms hat-shaped ascospores in deliquescent asci and appears homothallic. Analysis of nucleotide sequences from domains D1/D2 of large subunit (26S rDNA) separates the new species from Komagataella pastoris, the type species of the genus, and from Pichia pseudopastoris, which is renamed Komagataella pseudopastoris (Dlauchy, Tornai-Lehoczki, Fulop & Péter) Kurtzman comb. nov. (Type strain NRRL Y-27603T, CBS 9187T, NCAIM Y 01541T). On the basis of D1/D2 26S rDNA sequence analysis, the three species now assigned to the genus Komagataella represent a clade that is phylogenetically isolated from other ascomycetous yeast genera.