Mapping strains: mapping with multiply-marked strains developed at YGSC (AB5): mapping strains
rna strains are temperature-sensitive; they grow at 23C but not at 36C.
pet strains are unable to grow on non-fermentable substrates.
pet14 strains are leaky.
CUP1 strains are able to grow in the presence of 250 micrograms of copper sulfate per ml of medium.
gal strains may turn yellow.