5--5--5--trifluoroleucine and isopentyl-alcohol

We characterized a trifluoroleucine-resistant mutant of Saccharomyces cerevisiae, TFL20, that has a mutation in the LEU4 gene. We monitored the concentration of extracellular i-AmOH and intracellular amino acids, and compared the ratios of gene expression in TFL20 with the wild-type strain, K30. We found that the LEU1, LEU2, and BAT1 genes were up-regulated in TFL20 for metabolism, and that TFL20 simultaneously produced as much i-AmOH and leucine as K30 does.

Topics: 2-Isopropylmalate Synthase; Drug Resistance, Fungal; Leucine; Mutation; Pentanols; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins; Up-Regulation

Saccharomyces servazzii plays a crucial role in the making of Japanese radish pickles. To make more flavorsome pickles, we sought to generate trifluoroleucine-resistant mutants of S. servazzii. The three resulting mutants could be classified into two types: one that produces more isoamyl alcohol than the parental strain, and one that produces less. The first type has been well documented in Saccharomyces cerevisiae but the latter appears to be novel and has been characterized as such.

Topics: 2-Isopropylmalate Synthase; Cell Division; Dose-Response Relationship, Drug; Drug Resistance, Fungal; Leucine; Mutation; Pentanols; Saccharomyces; Species Specificity