Molecular analysis of mitochondrial DNA from tomato cell suspension cultures

Summary Mitochondrial DNA (mtDNA) from Lycopersicon esculentum was purified from cell suspension cultures. The DNA, isolated from mitochondria purified by two successive sucrose density gradients, was uncontaminated with nuclear DNA or DNA from proplastids. The total molecular weights of BamHI, BglI, and BglII fragments indicate a mitochondrial genome size of at least 270 kb. Cross hybridization between tomato mtDNA and cloned spinach plastid genes revealed some homology. In hybridization experiments using cloned mitochondrial rRNA genes and BamHI digested total mtDNA the presence of recombination repeats is demonstrated.