Schizosaccharomyces versatilis represents a distinct evolutionary lineage.

Abstract

The fission yeast species Schizosaccharomyces japonicus is currently divided into two varieties - S. japonicus var. japonicus and S. japonicus var. versatilis. Here we examine the var. versatilis isolate CBS5679. The CBS5679 genome shows 88% coding sequence identity to the reference genome of S. japonicus var. japonicus at the coding sequence level, with phylogenetic analyses suggesting that it has split from the S. japonicus lineage 25 million years ago. The CBS5679 genome contains a reciprocal translocation between chromosomes 1 and 2, together with several large inversions. The products of genes linked to the major translocation are associated with "metabolism" and "cellular assembly" ontology terms. We further show that CBS5679 does not generate viable progeny with the reference strain of S. japonicus. Although CBS5679 shares closer similarity to the "type" strain of var. versatilis as compared to S. japonicus, it is not identical to the type strain, suggesting population structure within var. versatilis. We recommend that the taxonomic status of S. japonicus var. versatilis is raised, with it being treated as a separate species, Schizosaccharomyces versatilis. Take-awayO_LIThe taxonomic status of Schizosaccharomyces versatilis is addressed. C_LIO_LIS. versatilis diverged from S. japonicus around 25 million years ago. C_LIO_LIS. versatilis does not produce viable progeny in crosses with S. japonicus. C_LIO_LIS. versatilis has a reciprocal translocation between chromosomes 1 and 2. C_LIO_LIThe Gene Ontology terms for genes in the translocations are enriched for terms connected to "metabolism" and "cellular assembly". C_LI