3.1.7.11 synthesis coexpression of geranyl diphosphate synthase and geraniol synthase in Escherichia coli. Gene copy number optimization leads to a 1.6fold increase of geraniol production when four copies of geranyl diphosphate synthase and one copy of geraniol synthase are used. The additional fermentation conditions optimization, including removal of organic layers and addition of n-decane, leads to a geraniol production of 74.6 mg/l 751256 3.1.7.11 synthesis overexpression of a mutant GES with a 5'-untranslated sequence designed for high translational efficiency, along with the additional expression of isopentenyl diphosphate isomerase, and geranyl diphosphate synthase, yields 300 mg/l/12 h geraniol and its derivatives in a shaking flask 751238 3.1.7.11 synthesis significant increase in geraniol synthesis is achieved by coexpression of geraniol synthase, mutant S80F of farnesyl diphosphate synthase, and the encoding genes involved in the whole mevalonic acid biosynthetic pathway in Escherichia coli. The additional optimization of medium composition, fermentation time, and addition of metal ions leads to the geraniol production of 48.5 mg/l 751253 3.1.7.11 synthesis synthesis of geraniol by expression of GES truncated at residue S43 in Saccharomyces cerevisiae. Coexpression of the reverse fusion of farnesyl diphosphate synthase Erg20 mutant F96W-N127W and truncated GES and another copy of farnesyl diphosphate synthase Erg20 mutant F96W-N127W promotes the geraniol titer to 523.96 mg/l at shakes flask level. A highest reported titer of 1.68 g/l geraniol in eukaryote cells is achieved in 2.0 l fed-batch fermentation under carbon restriction strategy 751469