title: Identification and sequence analysis of the genes encoding a polyketide synthase required for pyoluteorin biosynthesis in Pseudomonas fluorescens Pf-5.
abstract: Pyoluteorin is a chlorinated antifungal metabolite of mixed polyketide/amino-acid origin produced by certain strains of Pseudomonas spp., including the soil bacterium Pseudomonas fluorescens Pf-5. Sequence analysis of a gene cluster required for pyoluteorin biosynthesis by Pf-5 (Kraus, J., Loper, J., 1995. Appl. Environ. Microbiol. 61, 849-854) has identified two genes whose deduced peptide sequences exhibit characteristics of both fungal and bacterial Type I polyketide synthases (PKSs). The pyoluteorin PKS does not contain a loading domain that is typically present in bacterial Type I PKSs. Furthermore, this PKS possesses an acyltransferase domain that does not contain the conserved residues surrounding the active-site motif typically found in domains of similar function. Based on the organization of the functional domains within the pyoluteorin PKS, we propose a biosynthetic pathway analogous to non-aromatic polyketide biosynthesis within the Actinomycete bacteria that is responsible for the formation of the resorcinol moiety of pyoluteorin.
authors.affiliation: USDA-ARS, Corvallis, OR 973301, USA.
authors.forename: B
authors.initials: B
authors.lastname: Nowak-Thompson
authors.forename: S J
authors.initials: SJ
authors.lastname: Gould
authors.forename: J E
authors.initials: JE
authors.lastname: Loper
mesh_terms: D000213:Acyl Carrier Protein / Q000235:genetics; D000217:Acyltransferases / Q000235:genetics; D000429:Alcohol Oxidoreductases / Q000235:genetics; D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000096:biosynthesis*; D001426:Bacterial Proteins; D001483:Base Sequence; D001665:Binding Sites; D002384:Catalysis; D018076:DNA, Complementary; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009097:Multienzyme Complexes / Q000235:genetics*; D010636:Phenols; D048630:Polyketide Synthases; D011551:Pseudomonas fluorescens / Q000201:enzymology* / Q000235:genetics; D011758:Pyrroles; D017422:Sequence Analysis, DNA
chemical_list: D000213:Acyl Carrier Protein; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D018076:DNA, Complementary; D009097:Multienzyme Complexes; D010636:Phenols; D011758:Pyrroles; C095503:pyoluteorin; D048630:Polyketide Synthases; D000429:Alcohol Oxidoreductases; C087192:polyketide synthase ketoreductase; D000217:Acyltransferases; C087193:polyketide beta-ketoacylsynthase