title: Disruption of the cyclosporin synthetase gene of Tolypocladium niveum.
abstract: Cyclosporin A is a potent and clinically-important immunosuppressive drug (SandimmunR). It is produced by the fungus Tolypocladium niveum. A transformation system for T. niveum ATCC34921 based on hygromycin selection was established. In order to obtain a T. niveum promoter, the cyclophilin gene was isolated using the Neurospora crassa gene as probe. A plasmid vector was constructed in which the promoter region of the T. niveum cyclophilin gene was fused to a bacterial hygromycin phosphotransferase gene. Protoplasts were transformed with this plasmid and hygromycin-resistant transformants were isolated. Using this transformation system, mutants of T. niveum with disrupted versions of the cyclosporin synthetase gene (simA) were engineered by DNA-mediated transformation. Disruption of the gene resulted in loss of the ability to produce cyclosporins.
authors.affiliation: Biochemie Ges.m.b.H., Kufstein-Schaftenau, Austria.
authors.forename: G
authors.initials: G
authors.lastname: Weber
authors.forename: E
authors.initials: E
authors.lastname: Leitner
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D005800:Genes, Fungal; D005822:Genetic Vectors; D003904:Mitosporic Fungi / Q000201:enzymology / Q000235:genetics*; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes / Q000235:genetics*; D009492:Neurospora crassa / Q000235:genetics; D009838:Oligodeoxyribonucleotides; D010453:Peptide Synthases / Q000235:genetics*; D010957:Plasmids; D015183:Restriction Mapping; D014170:Transformation, Genetic
chemical_list: D009097:Multienzyme Complexes; D009838:Oligodeoxyribonucleotides; C048525:cyclosporin A synthetase; D010453:Peptide Synthases