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Abstract
A preliminary genetic analysis was carried out on 14 mutants
of Saccharomyces cerevisiae resistant to respiratory repression induced
by D(+) glucosamine. One mutant strain (GR133) carried a nuclear mutation
(designated gay-1 ) conferring glucosamine resistance. Five strains
(GR7, GR62, GR120, GR124 and GR125) were either sterile or carried
conditional lethality precluding further genetic analysis. The
remaining group of mutants (GR5, GR6, GR8, GR9, GR10, GR22,
GR112 and GR127) were found to carry one or more cytoplasmic G determ-
inants .
Detailed investigation of GRlOand GR6 derivatives demonstrated that:
p
1. G can be reduced or eliminated by ethidium bromide (EB) treatment.
2. G can be quantitatively enriched in glucosamine containing medium.
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3. a cross between a G enriched GR10 derivative and a neutral EB
induced petite displayed phenotypic G dominance.
4. GR6 and GR10 derivatives were sensitive to oligomycin, erythromycin
and chloramphenicol
.
5. stock strains resistant to these drugs were glucosamine sensitive.
These observations 1 —>5 suggest that GR10 and probably GR6 carry novel
mutation (s) located on mitochondrial DNA. The locus of GR10 was
designated [CAT-1]
.