Molecular cloning, characterization and heterologous expression in Saccharomyces cerevisiae of a mevalonate diphosphate decarboxylase cDNA from Ginkgo biloba

Mevalonate diphosphate decarboxylase (MVD; EC4.1.1.33) catalyses the conversion of mevalonate diphosphate to isopentenyl diphosphate (IPP), which is a key skeleton for numerous functionally important secondary metabolites. A full-length cDNA of MVD was isolated from Ginkgo biloba (designated as GbMVD) using rapid amplification of cDNA ends (RACE). GbMVD was 1958 bp with poly(A) tailing and contained a 1290-bp open reading frame encoding a 430-amino acid protein. The deduced GbMVD protein had a deduced molecular weight of about 48 kDa and isoelectric point of 5.83, and it showed high similarity to MVDs from other species. The 3D-structure modelling showed that the 3D model of GbMVD had a similar P loop as that of yeast. Phylogenetic tree analysis revealed that GbMVD shared the same ancestor with MVDs from other species, and it had a closer relationship with those from plant species. Southern blot analysis indicated that GbMVD might belong to a small multigene family. Transcript accumulation analysis revealed that GbMVD was transcribed in root, stem and leaf tissues. Functional complementation of GbMVD in an MVD-deficient Saccharomyces cerevisiae strain MN19-34 (erg19ts) confirmed that GbMVD mediated the conversion of mevalonate diphosphate to IPP and that it is a functional gene