Sporulation in mitochondrial OXI3 mutants of Saccharomyces cerevisiae : A correlation with the genetic map.

By use of a set of mitochondrial oxi3 mutants (mit (-), defective in cytochrome oxidase) we have shown that sporulation is possible at a very low level of respiration (below l% of the wild type respiration). A specific role for oxygen in biosynthesis during sporulation is suggested. Correlation of these results with the genetic map of the OXI3 region reveals that one group of mutants, mapping in the central part of the OXI3 region, is capable of sporulation.