title: The albonoursin gene Cluster of S noursei biosynthesis of diketopiperazine metabolites independent of nonribosomal peptide synthetases.
abstract: Albonoursin [cyclo(deltaPhe-DeltaLeu)], an antibacterial peptide produced by Streptomyces noursei, is one of the simplest representatives of the large diketopiperazine (DKP) family. Formation of alpha,beta unsaturations was previously shown to occur on cyclo(L-Phe-L-Leu), catalyzed by the cyclic dipeptide oxidase (CDO). We used CDO peptide sequence information to isolate a 3.8 kb S. noursei DNA fragment that directs albonoursin biosynthesis in Streptomyces lividans. This fragment encompasses four complete genes: albA and albB, necessary for CDO activity; albC, sufficient for cyclic dipeptide precursor formation, although displaying no similarity to non ribosomal peptide synthetase (NRPS) genes; and albD, encoding a putative membrane protein. This first isolated DKP biosynthetic gene cluster should help to elucidate the mechanism of DKP formation, totally independent of NRPS, and to characterize novel DKP biosynthetic pathways that could be engineered to increase the molecular diversity of DKP derivatives.
authors.affiliation: CEA/Saclay, Département d'Ingénierie et d'Etudes des Protéines, F91191 Gif-sur-Yvette Cedex, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Lautru
authors.forename: Muriel
authors.initials: M
authors.lastname: Gondry
authors.forename: Roger
authors.initials: R
authors.lastname: Genet
authors.forename: Jean Luc
authors.initials: JL
authors.lastname: Pernodet
mesh_terms: D000595:Amino Acid Sequence; D004269:DNA, Bacterial / Q000235:genetics / Q000302:isolation & purification; D054659:Diketopiperazines; D005810:Multigene Family; D009601:Nitroreductases; D016366:Open Reading Frames; D010088:Oxidoreductases / Q000235:genetics; D010453:Peptide Synthases / Q000235:genetics; D010879:Piperazines / Q000378:metabolism*; D016415:Sequence Alignment; D013302:Streptomyces / Q000235:genetics* / Q000378:metabolism
chemical_list: D004269:DNA, Bacterial; D054659:Diketopiperazines; D010879:Piperazines; C006442:albonoursin; D010088:Oxidoreductases; C424906:cyclic dipeptide oxidase; D009601:Nitroreductases; D010453:Peptide Synthases; C104385:non-ribosomal peptide synthase