title: Isolation and characterization of pcsB, the gene for a polyene carboxamide synthase that tailors pimaricin into AB-400.
abstract: From cell-free extracts of Streptomyces RGU5.3, a tailoring activity of pimaricin, leading to the biosynthesis of its natural carboxamide derivative AB-400, was recently identified. The two polyene macrolides, pimaricin and AB-400, were produced in almost equal quantities and can be detected in the fermentation broth of the producer strain. This report concerns the isolation and partial characterization of the gene, polyene carboxamide synthase (pcsB), responsible for the bioconversion. The gene encoded an asparagine synthase-like protein, belonging to the type II glutamine amidotransferase family, and was named pcsB. The fermentation broth of a recombinant strain carrying the engineered pcsB gene under the control of the inducible tipA promoter within an integrative vector produces the carboxamide AB-400 as the main polyene macrolide.
authors.affiliation: Centro Nacional de Biotecnología del CSIC, Campus de la UAM, Darwin 3, Cantoblanco, 28049 Madrid, Spain.
authors.forename: Domingo
authors.initials: D
authors.lastname: Miranzo
authors.forename: Elena M
authors.initials: EM
authors.lastname: Seco
authors.forename: Trinidad
authors.initials: T
authors.lastname: Cuesta
authors.forename: Francisco
authors.initials: F
authors.lastname: Malpartida
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D005285:Fermentation; D005798:Genes, Bacterial; D018942:Macrolides / Q000378:metabolism*; D010866:Natamycin / Q000378:metabolism*; D013302:Streptomyces / Q000201:enzymology* / Q000235:genetics; D000637:Transaminases / Q000235:genetics* / Q000378:metabolism
chemical_list: C413567:AB 400; D001426:Bacterial Proteins; D018942:Macrolides; D010866:Natamycin; D000637:Transaminases; C020656:glutamine-pyruvate aminotransferase