A yeast with linear molecules of mitochondrial DNA

Mitochondrial DNA from the yeast strain SR23, tentatively allocated to the species Candida rhagii, consists of linear molecules 30 kb long. This has been demonstrated by restriction analysis and selective radioactive labelling of terminal restriction fragments. Preliminary sequence analysis indicated that the two ends of the molecule are formed by inverted repeats. The arrangement of several genes in the mitochondrial genome of C. rhagii SR23 was established by specific hybridisation with probes prepared from mitochondrial DNA of Saccharomyces cerevisiae. The arrangement is unique, with genes coding for the two ribosomal RNAs placed widely apart. Intron(s) may be present in the gene coding for cytochrome b.