Interaction between rough phenotype and amino acid auxotrophy in Saccharomyces cerevisiae.

In Saccharomyces cerevisiae a tryptophan requirement suppresses the rough colony phenotype that is produced by mutants at three separate loci. The suppression is strongly influenced by the genetic background and is excercised by both tested tryptophan loci. Very high concentrations of tryptophan in the growth medium relieve the suppression in some segregants. A similar suppression of the rough phenotype was observed in a mutant requiring lysine, while neither histidine nor adenine requirements were effective in that respect. [ABSTRACT FROM AUTHOR]