Open AccessEvolutionary relationships between the former species Saccharomyces uvarum and the hybrids Saccharomyces bayanus and Saccharomyces pastorianus ; reinstatement of Saccharomyces uvarum (Beijerinck) as a distinct species
Author(s) -
Nguyen HuuVang,
Gaillardin Claude
Publication year - 2005
Publication title -
fems yeast research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.991
H-Index - 92
eISSN - 1567-1364
pISSN - 1567-1356
DOI - 10.1016/j.femsyr.2004.12.004
Subject(s) - biology , genetics , strain (injury) , gene , hybrid , genome , synonym (taxonomy) , botany , genus , anatomy
Analysis of the nucleotide sequence of the GDH1 homologues from Saccharomyces bayanus strain CBS 380 T and S. pastorianus strains showed that they share an almost identical sequence, SuGDH1 *, which is a diverged form of the SuGDH1 from the type strain of the former species S. uvarum , considered as synonym of S. bayanus . SuGDH1 * is close to but differs from SuGDH1 by the accumulation of a high number of neutral substitutions designated as Multiple Neutral Mutations Accumulation (MNMA). Further analysis carried out with three other markers, BAP2 , HO and MET2 showed that they have also diverged from their S. uvarum counterparts by MNMA. S. bayanus CBS 380 T is placed between S. uvarum and S. pastorianus sharing MET2, CDC91 sequences with the former and BAP2, GDH1 , HO sequences with the latter. S. bayanus CBS 380 T has been proposed to be a S. uvarum / S. cerevisiae hybrid and this proposal is confirmed by the presence in its genome a S. cerevisiae SUC4 gene. Strain S. bayanus CBS 380 T , with a composite genome, is genetically isolated from strains of the former S. uvarum species, thus justifying the reinstatement of S. uvarum as a distinct species.