title: The mitochondrial genome can be altered or lost without lethal effect in the petite-negative yeast Debaryomyces (Schwanniomyces) occidentalis.
abstract: The nature of mutations affecting several cytochrome-deficient mutants of Debaryomyces (Schwanniomyces) occidentalis has been characterized. The DR12 mutant, which is deficient in cytochrome b, and the B10Mn mutant, which is deficient in cytochromes b and a, a3, are deleted in the mitochondrial CYB and COX1 genes respectively. The B10 strain, which is partially deficient in cytochrome b, has no detectable change in its mitochondrial DNA and possibly carries nuclear lesion(s). These three mutants, unlike the rho(-) and rho degrees "petite" mutants of Saccharomyces cerevisiae, can still grow on non-fermentable substrates, due to the development of a salicylhydroxamic acid (SHAM)-sensitive alternative pathway linked to phosphorylation at site 1. A gly(-) mutant lacking mtDNA and respiratory capacity has been isolated. For the first time, it is demonstrated that mtDNA can be altered or even lost without lethal consequence in D. occidentalis, although this yeast was classified as a petite-negative species.
authors.affiliation: Centre de Génétique Moléculaire, UPR 2167 du CNRS associée a l'UPMC, 1 Avenue de la terrasse, Bât. 26, 91198 Gif-sur-Yvette, France. fernet@cgm.cnrs-gif.fr
authors.forename: Caroline S
authors.initials: CS
authors.lastname: Fernet
authors.forename: G Desmond
authors.initials: GD
authors.lastname: Clark-Walker
authors.forename: Maurice L
authors.initials: ML
authors.lastname: Claisse
mesh_terms: D002455:Cell Division / Q000187:drug effects / Q000235:genetics; D019069:Cell Respiration / Q000235:genetics; D002701:Chloramphenicol / Q000494:pharmacology; D051545:Cyclooxygenase 1; D003573:Cytochrome b Group / Q000172:deficiency / Q000235:genetics; D003580:Cytochromes / Q000187:drug effects / Q000378:metabolism; D004272:DNA, Mitochondrial / Q000235:genetics; D004917:Erythromycin / Q000494:pharmacology; D005656:Fungal Proteins / Q000096:biosynthesis / Q000235:genetics; D007527:Isoenzymes / Q000235:genetics; D008928:Mitochondria / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics; D004718:Saccharomycetales / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D017384:Sequence Deletion; D013057:Spectrum Analysis
chemical_list: D003573:Cytochrome b Group; D003580:Cytochromes; D004272:DNA, Mitochondrial; D005656:Fungal Proteins; D007527:Isoenzymes; D004917:Erythromycin; D002701:Chloramphenicol; D051545:Cyclooxygenase 1; D011451:Prostaglandin-Endoperoxide Synthases