GENETIC EVIDENCE FOR 'DARWINIAN' SELECTION AT THE MOLECULAR LEVEL. I. THE EFFECT OF THE SUPPRESSIVE FACTOR ON CYTOPLASMICALLY-INHERITED ERYTHROMYCIN-RESISTANCE IN SACCHAROMYCES CEREVISIAE

Abstract

A study of the suppressive factor of Saccharomyces cerevisiae and its effects on the transmission of cytoplasmically-inherited erythromycin resistance showed that loss of erythromycin resistance was contingent on suppressitivity, and that strains carrying the suppressive factor continuously segregated progeny cells that lacked resistance. It was suggested that suppressitivity is due to the presence, in suppressive strains, of rapidly-replicating abnormal mitochondrial DNA, and that loss of erythromycin resistance (coded for by normal mitochondrial DNA) is due to the replicative superiority of abnormal mitochondrial DNA.