title: Genetic potential for secondary metabolite production in stromatolite communities.
abstract: The cyanobacterial communities associated with stromatolites surviving in extreme habitats are a potentially rich source of bioactive secondary metabolites. We screened for the potential for production of bioactive metabolites in diverse species of cyanobacteria isolated from stromatolites in Hamelin Pool, Shark Bay, Australia. Using degenerate primer sets, putative peptide synthetase and polyketide synthase genes were detected from strains of Symploca, Leptolyngybya, Microcoleus, Pleuorocapsa, and Plectonema sp. Sequence analysis indicates the enzymes encoded by these genes may be responsible for the production of different secondary metabolites, such as hepatotoxins and antibiotics. Computer modelling was also conducted to predict the putative amino acid recognised by the unknown adenylation domain in the NRPS sequences. Mass spectral analysis also allowed the putative identification of the cyclic peptides cyanopeptolin S and 21-bromo-oscillatoxin A in two of the isolates. This is the first time evidence of secondary metabolite production has been shown in stromatolite-associated microorganisms.
authors.affiliation: School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney 2052, Australia. brendan.burns@unsw.edu.au
authors.forename: Brendan P
authors.initials: BP
authors.lastname: Burns
authors.forename: Alexander
authors.initials: A
authors.lastname: Seifert
authors.forename: Falicia
authors.initials: F
authors.lastname: Goh
authors.forename: Francesco
authors.initials: F
authors.lastname: Pomati
authors.forename: Anne-Dorothee
authors.initials: AD
authors.lastname: Jungblut
authors.forename: Alper
authors.initials: A
authors.lastname: Serhat
authors.forename: Brett A
authors.initials: BA
authors.lastname: Neilan
mesh_terms: D000900:Anti-Bacterial Agents / Q000378:metabolism*; D001315:Australia; D001427:Bacterial Toxins / Q000378:metabolism*; D000458:Cyanobacteria / Q000201:enzymology* / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification; D017753:Ecosystem; D019015:Geologic Sediments / Q000737:chemistry / Q000382:microbiology*; D008969:Molecular Sequence Data; D010453:Peptide Synthases / Q000235:genetics / Q000378:metabolism; D010802:Phylogeny; D048630:Polyketide Synthases / Q000235:genetics / Q000378:metabolism; D016133:Polymerase Chain Reaction; D012623:Seawater / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D000900:Anti-Bacterial Agents; D001427:Bacterial Toxins; D048630:Polyketide Synthases; D010453:Peptide Synthases