title: Molecular and biochemical studies of chondramide formation-highly cytotoxic natural products from Chondromyces crocatus Cm c5.
abstract: The jaspamide/chondramide family of depsipeptides are mixed PKS/NRPS natural products isolated from marine sponges and a terrestrial myxobacterium that potently affect the function of the actin cytoskeleton. As a first step to improve production in heterologous host cells and permit genetic approaches to novel analogs, we have cloned and characterized the chondramide biosynthetic genes from the myxobacterium Chondromyces crocatus Cm c5. In addition to the expected PKS and NRPS genes, the cluster encodes a rare tyrosine aminomutase for beta-tyrosine formation and a previously unknown tryptophan-2-halogenase. Conditions for gene transfer into C. crocatus Cm c5 were developed, and inactivation of several genes corroborated their proposed function and served to define the boundaries of the cluster. Biochemical characterization of the final NRPS adenylation domain confirmed the direct activation of beta-tyrosine, and fluorinated chondramides were produced through precursor-directed biosynthesis.
authors.affiliation: Pharmaceutical Biotechnology, Saarland University, P.O. Box 151150, 66041 Saarbrücken, Germany.
authors.forename: Shwan
authors.initials: S
authors.lastname: Rachid
authors.forename: Daniel
authors.initials: D
authors.lastname: Krug
authors.forename: Brigitte
authors.initials: B
authors.lastname: Kunze
authors.forename: Irene
authors.initials: I
authors.lastname: Kochems
authors.forename: Maren
authors.initials: M
authors.lastname: Scharfe
authors.forename: T Mark
authors.initials: TM
authors.lastname: Zabriskie
authors.forename: Helmut
authors.initials: H
authors.lastname: Blöcker
authors.forename: Rolf
authors.initials: R
authors.lastname: Müller
mesh_terms: D000225:Adenine / Q000378:metabolism; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000737:chemistry* / Q000235:genetics / Q000633:toxicity; D001688:Biological Products / Q000096:biosynthesis* / Q000737:chemistry* / Q000235:genetics / Q000633:toxicity; D003001:Cloning, Molecular; D047630:Depsipeptides / Q000096:biosynthesis* / Q000737:chemistry* / Q000235:genetics / Q000633:toxicity; D015870:Gene Expression; D016680:Genome, Bacterial / Q000235:genetics; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics; D009231:Myxococcales / Q000235:genetics / Q000378:metabolism*; D010957:Plasmids / Q000235:genetics; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014364:Tryptophan / Q000031:analogs & derivatives / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D001688:Biological Products; D047630:Depsipeptides; C026927:5-fluorotryptophan; D014364:Tryptophan; D000225:Adenine