Summary. It was found that the phenotypic suppression induced by the paromamine-containing antibiotic paromomycin could be significantly strengthened by a ribosomal suppressor mutation in yeast Saccharomyces cerevisiae. As a result the suppressor efficient towards ochre mutations in the presence of paromomycin acquired the ability to suppress both amber and opal mutations. It is suggested that phenotypic suppression by paromomycin and genotypic suppression by sup 1 both involve a similar mechanism of misreading.
