Physical mapping of the Xba I, Hinc II, Bgl II, Xho I, Sst I, and Pvu II restriction endonuclease cleavage fragments of mitochondrial DNA of S. cerevisiae.

A detailed molecular dissection of the yeast mitochondrial genome can be made with restriction endonucleases that generate site-specific cuts in DNA. The ordering of restriction fragments provides the basis of the physical mapping of mitochondrial transcripts and antibiotic resistance (antR) loci, and is a means of analyzing the molecular organization of mtDNA of petite and mit- deletion mutants. We have previously mapped the sites in the mtDNA of yeast strain MH41-7B recognized by the endonucleases Eco RI, Hpa I, Hind III, Bam HI, Sal I, Pst I, and Hha I, providing a total of 41 cleavage sites. We have now mapped the sites recognized by the endonucleases Xba I, Hinc II, Bgl II, Pvu II, Xho I, and Sst I, which make 6, 13, 5, 6, 2, and 2 cuts, respectively. Fragment maps for each of these endonuclease sites were derived by analysis of the products of double-enzyme digests and by hybridization of 3H-cRNA probes transcribed from low-kinetic-complexity petite mtDNAs to restriction fragments generated by various combinations of enzymes.