title: Previously Uncultured Marine Bacteria Linked to Novel Alkaloid Production.
abstract: Low-nutrient media and long incubation times facilitated the cultivation of 20 taxonomically diverse Gram-negative marine bacteria within the phyla Bacteroidetes and Proteobacteria. These strains comprise as many as three new families and include members of clades that had only been observed using culture-independent techniques. Chemical studies of the type strains representing two new families within the order Cytophagales led to the isolation of nine new alkaloid secondary metabolites that can be grouped into four distinct structure classes, including azepinones, aziridines, quinolones, and pyrazinones. Several of these compounds possess antibacterial properties and appear, on structural grounds, to be produced by amino acid-based biosynthetic pathways. Our results demonstrate that relatively simple cultivation techniques can lead to the isolation of new bacterial taxa that are capable of the production of alkaloid secondary metabolites with antibacterial activities. These findings support continued investment in cultivation techniques as a method for natural product discovery.
authors: Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA 92093-0204, USA.
authors: Eun Ju
authors: EJ
authors: Choi
authors: Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA 92093-0204, USA.
authors: Sang-Jip
authors: SJ
authors: Nam
authors: Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA 92093-0204, USA.
authors: Lauren
authors: L
authors: Paul
authors: Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA 92093-0204, USA.
authors: Deanna
authors: D
authors: Beatty
authors: Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA 92093-0204, USA.
authors: Christopher A
authors: CA
authors: Kauffman
authors: Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA 92093-0204, USA.
authors: Paul R
authors: PR
authors: Jensen
authors: Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA 92093-0204, USA. Electronic address: wfenical@ucsd.edu.
authors: William
authors: W
authors: Fenical
mesh_terms: D000470:Alkaloids / Q000096:biosynthesis* / Q000737:chemistry; D000900:Anti-Bacterial Agents / Q000096:biosynthesis* / Q000302:isolation & purification; D059001:Aquatic Organisms / Q000166:cytology / Q000302:isolation & purification / Q000378:metabolism*; D041963:Bacteroidetes / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D020560:Proteobacteria / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D017422:Sequence Analysis, DNA
chemical_list: D000470:Alkaloids; D000900:Anti-Bacterial Agents