title: Optimization of heterologous production of the polyketide 6-MSA in Saccharomyces cerevisiae.
abstract: Polyketides are a group of natural products that have gained much interest due to their use as antibiotics, cholesterol lowering agents, immunosuppressors, and as other drugs. Many organisms that naturally produce polyketides are difficult to cultivate and only produce these metabolites in small amounts. It is therefore of general interest to transfer polyketide synthase (PKS) genes from their natural sources into heterologous hosts that can over-produce the corresponding polyketides. In this study we demonstrate the heterologous expression of 6-methylsalicylic acid synthase (6-MSAS), naturally produced by Penicillium patulum, in the yeast Saccharomyces cerevisiae. In order to activate the PKS a 4'-phosphopantetheinyl transferase (PPTase) is required. We therefore co-expressed PPTases encoded by either sfp from Bacillus subtilis or by npgA from Aspergillus nidulans. The different strains were grown in batch cultures. Growth and product concentration were measured and kinetic parameters were calculated. It was shown that both PPTases could be efficiently used for activation of PKS's in yeast as good yields of 6-MSA were obtained with both enzymes.
authors.affiliation: Center for Microbial Biotechnology, BioCentrum-DTU, Building 223, Kgs. Lyngby 2800, Denmark.
authors.forename: Songsak
authors.initials: S
authors.lastname: Wattanachaisaereekul
authors.forename: Anna Eliasson
authors.initials: AE
authors.lastname: Lantz
authors.forename: Michael Lynge
authors.initials: ML
authors.lastname: Nielsen
authors.forename: Olafur S
authors.initials: OS
authors.lastname: Andrésson
authors.forename: Jens
authors.initials: J
authors.lastname: Nielsen
mesh_terms: D001233:Aspergillus nidulans / Q000201:enzymology / Q000235:genetics; D001412:Bacillus subtilis / Q000201:enzymology / Q000235:genetics; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D018533:Biomass; D019149:Bioreactors / Q000382:microbiology; D018929:Cell Culture Techniques; D004789:Enzyme Activation; D005285:Fermentation; D007700:Kinetics; D010957:Plasmids; D048630:Polyketide Synthases / Q000096:biosynthesis*; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics; D012459:Salicylates / Q000378:metabolism*; D017855:Transferases (Other Substituted Phosphate Groups) / Q000737:chemistry / Q000378:metabolism; D014170:Transformation, Genetic
chemical_list: D001426:Bacterial Proteins; D012459:Salicylates; C082662:phosphopantetheinyl transferase; D048630:Polyketide Synthases; D017855:Transferases (Other Substituted Phosphate Groups); C005236:6-methylsalicylic acid