The improvement of amorpha-4,11-diene production by a yeast-conform variant

AIMS

To investigate the effect of the yeast-conform variant of the Artemisia annua gene encoding for amorpha-4,11-diene synthase (ADS) on the production of amorpha-4,11-diene in a transformed yeast.

METHODS AND RESULTS

The ADS gene was mutated to the yeast-conform variant ADSm. The ADSm synthesis was performed based on step-by-step extension of a short region of the gene through a series of polymerase chain reactions (PCR). The artificial ADSm gene contained codons preferred by the yeast translation machinery. The sequence was then integrated into a yeast expression vector pYeDP60. The fusion construct was active and the transformed yeast cells produced higher level of amorpha-4,11-diene compared with the plant gene-transformed yeast cells.

CONCLUSIONS

Strains transformed with the yeast-conform allele (ADSm) were more efficient in terms of production of amorpha-4,11-diene than those transformed with the plant gene.

SIGNIFICANCE AND IMPACT OF THE STUDY

We demonstrated that yeast-conform allele of foreign genes by serial PCR reactions can be a solution to low efficiency of heterologous gene expression in Saccharomyces cerevisiae cells.

Cytochalasin D from Hypocrella bambusae

Cytochalasin D which shows marked cytotoxic effects on multi-tumor cells was newly isolated at high content(5.28 mg/g, dry weight) from Fungus Hypocrella bambusae(B.et Br.) Sacc. Its structure was elucidated by spectroscopic methods. Two-dimensional NMR techniques were applied to make complete assignment for the 1H- and 13C-NMR chemical shifts of this compound.