title: Inheritance and organisation of the mitochondrial genome differ between two Saccharomyces yeasts.
abstract: Petite-positive Saccharomyces yeasts can be roughly divided into the sensu stricto, including Saccharomyces cerevisiae, and sensu lato group, including Saccharomyces castellii; the latter was recently studied for transmission and the organisation of its mitochondrial genome. S. castellii mitochondrial molecules (mtDNA) carrying point mutations, which confer antibiotic resistance, behaved in genetic crosses as the corresponding point mutants of S. cerevisiae. While S. castellii generated spontaneous petite mutants in a similar way as S. cerevisiae, the petites exhibited a different inheritance pattern. In crosses with the wild type strains a majority of S. castellii petites was neutral, and the suppressivity in suppressive petites was never over 50%. The two yeasts also differ in organisation of their mtDNA molecules. The 25,753 bp sequence of S. castellii mtDNA was determined and the coding potential of both yeasts is similar. However, the S. castellii intergenic sequences are much shorter and do not contain sequences homologous to the S. cerevisiae biologically active intergenic sequences, as ori/rep/tra, which are responsible for the hyper-suppressive petite phenotype found in S. cerevisiae. The structure of one suppressive S. castellii mutant, CA38, was also determined. Apparently, a short direct intergenic repeat was involved in the generation of this petite mtDNA molecule.
authors.affiliation: BioCentrum-DTU, Technical University of Denmark, Building 301, DK-2800 Kgl. Lyngby, Denmark.
authors.forename: Randi F
authors.initials: RF
authors.lastname: Petersen
authors.forename: Rikke B
authors.initials: RB
authors.lastname: Langkjaer
authors.forename: Jeanne
authors.initials: J
authors.lastname: Hvidtfeldt
authors.forename: Judita
authors.initials: J
authors.lastname: Gartner
authors.forename: William
authors.initials: W
authors.lastname: Palmen
authors.forename: David W
authors.initials: DW
authors.lastname: Ussery
authors.forename: Jure
authors.initials: J
authors.lastname: Piskur
mesh_terms: D001483:Base Sequence; D003433:Crosses, Genetic; D004271:DNA, Fungal / Q000235:genetics*; D021901:DNA, Intergenic / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics*; D016681:Genome, Fungal; D008969:Molecular Sequence Data; D010101:Oxygen Consumption / Q000235:genetics; D017354:Point Mutation; D012440:Saccharomyces / Q000235:genetics* / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D013045:Species Specificity
chemical_list: D004271:DNA, Fungal; D021901:DNA, Intergenic; D004272:DNA, Mitochondrial