Open AccessClosed‐Circular DNA from Mitochondrial‐Enriched Fractions of Four Petite ‐Negative Yeasts
Author(s) -
O'CONNOR Ralph M.,
McARTHUR Craig R.,
CLARKWALKER G. Desmond
Publication year - 1975
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1975.tb04050.x
Subject(s) - mitochondrial dna , schizosaccharomyces pombe , candida parapsilosis , dna , kluyveromyces lactis , yeast , biology , saccharomyces cerevisiae , genetics , microbiology and biotechnology , gene , candida albicans
Closed‐circular DNA has been isolated from mitochondrial‐enriched fractions from four petite ‐negative' yeasts. Electron microscope analysis has shown in each case the presence of a large discrete size class of circular DNA greater than 6 μm in length and smaller heterodisperse circular DNA less than 6 μm. Length and molecular weight measurements of the large circular DNA are: Candida parapsilosis , 11.14 ± 0.45 μ and 23.1 × 10 6 ; Hansenula wingei , 8.22 ± 0.43 μm and 17.3 × 10 6 ; Kluyveromyces lactis , 11.44 ± 0.20 μm and 24.0 × 10 6 and Schizosaccharomyces pombe , 6.04 ± 0.16 μm and 12.5 × 10 6 . These circular DNAs are thought to be mitochondrial DNA on the basis of their buoyant densities and their enrichment with mitochondria. The finding of a gross size difference between mitochondrial DNA from petite ‐negative yeasts and Saccharomyces cerevisiae focuses attention on the suggestion that certain unique properties of the latter organism's mitochodrial DNA may be of relevance to the mechanism of the petite mutation in yeast.