Characterization of a lysine-to-glutamic acid mutation in a conservative sequence of farnesyl diphosphate synthase from Saccharomyces cerevisiae.

The mutant gene erg20-2 was isolated from a yeast strain defective in farnesyl diphosphate synthase (FPPS). This strain had the unusual property of excreting prenyl alcohols such as geraniol. The nucleotide (nt) sequence, compared with that of the wild-type gene, showed a single nt change, resulting in a Lys197-->Glu substitution in FPPS which is directly involved in terpenic alcohol formation. In addition, disruption of ERG20 revealed that in yeast no other prenyl transferase is able to synthesize the FPP molecules required for essential non-sterol metabolites.