title: Copy number modulation in an autoselection system for stable plasmid maintenance in Saccharomyces cerevisiae.
abstract: Efficient expression of a foreign gene requires a stable vector present at a high number of copies per cell. We have constructed an autoselection system for the stable maintenance of expression vector in the yeast Saccharomyces cerevisiae that uses the fructose 1,6-bisphosphate aldolase gene (FBA1) to stabilize plasmids in cells bearing a disruption of the chromosomal FBA1 gene. This system allowed us to obtain stable production of a reporter heterologous enzyme (Escherichia coli beta-galactosidase) in rich media. By using an inducible promoter to regulate the expression of FBA1 gene, we have also obtained the modulation of plasmid copy number by carbon source.
authors.affiliation: Dipartimento di Fisiologia e Biochimica Generali, Universitá di Milano, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Compagno
authors.forename: A
authors.initials: A
authors.lastname: Tura
authors.forename: B M
authors.initials: BM
authors.lastname: Ranzi
authors.forename: L
authors.initials: L
authors.lastname: Alberghina
authors.forename: E
authors.initials: E
authors.lastname: Martegani
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics; D001709:Biotechnology / Q000379:methods*; D003470:Culture Media; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D005634:Fructose-Bisphosphate Aldolase / Q000235:genetics; D005784:Gene Amplification / Q000235:genetics*; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics; D010957:Plasmids / Q000235:genetics* / Q000502:physiology; D011401:Promoter Regions, Genetic / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D001616:beta-Galactosidase / Q000096:biosynthesis / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D001616:beta-Galactosidase; D005634:Fructose-Bisphosphate Aldolase