Involvement of mitochondrial protein synthesis in sporulation: effects of erythromycin on macromolecular synthesis, meiosis, and ascospore formation in Saccharomyces cerevisiae.

Cells of strain Z270 (MAT alpha/MAT alpha) of Saccharomyces cerevisiae did not undergo ascospore formation in buffered or unbuffered acetate sporulation medium in the presence of erythromycin. The drug inhibited sporulation when added within the first 6 to 8 h and affected to different extents some of the metabolic and sporulation-specific events that normally occur during this period. In sporulation medium, protein synthesis was highly sensitive to erythromycin, whereas RNA synthesis was unaffected and premeiotic DNA synthesis was partially inhibited. Intragenic recombination occurred at normal rates for the various heteroallelic loci tested, but rates of intergenic recombination were markedly reduced, and commitment to haploidization did not occur; hence, development was evidently arrested between intragenic and intergenic recombination. Cells kept for 8 h in acetate sporulation medium that were ready for sporulation in water without erythromycin failed to sporulate in water containing the drug, indicating that erythromycin can inhibit sporulation independent of acetate utilization.