Monacolin k, cholesterol serum synthesis inhibitor, is a secondary metabolite synthesized by polyketides from Monascus. In this study, a BAC (Bacterial Artificial Chromosome) clone, mps01, was screened from the mpb01 BAC library constructed with Monascus sp. BCRC 38072 genomic DNA. The putative monacolin k biosynthesis gene cluster was found in mps01 clone, genomic sequencing and Northern blot analysis showed that nine putative genes for monacolin k biosynthesis were located within a 41-kb region and were transcribed when monacolin k was produced. The deduced amino acid sequences encoded by the nine genes, designated mkAÂ¡VmkI, sharing similarities of over 54% with lovastatin gene cluster contained in Aspergillus terreus were assumed to be involved in monacolin k biosynthesis. The mkA gene encoding nonaketide synthase and sfp gene, a phosphopantetheinyl transferase required to convert the expressed apo-PKS to its holo form and obtained from Bacillus subtilis, were coexpressed in Escherichia coli. Novel polyketide compounds produced in the transformant were determined by LC-ESIMS and found at wavelength of 360 nm. Further study on the structure of these polyketides will be presented.
Full conference title:
23rd Fungal Genetics Conference
- Fungal Genetics Conference 23rd (2002)