title: Characterization of microcystin production in an Antarctic cyanobacterial mat community.
abstract: Cyanobacteria are well known for their production of non-ribosomal cyclic peptide toxins, including microcystin, in temperate and tropical regions, however, the production of these compounds in extremely cold environments is still largely unexplored. Therefore, we investigated the production of protein phosphatase inhibiting microcystins by Antarctic cyanobacteria. We have identified microcystin-LR and for the first time [D-Asp3] microcystin-LR by mass spectrometric analysis in Antarctic cyanobacteria. The microcystins were extracted from a benthic microbial community that was sampled from a meltwater pond (Fresh Pond, McMurdo Ice Shelf, Antarctica). The extracted cyanobacterial cyclic peptides were equivalent to 11.4 ng MC-LR per mg dry weight by semi-quantitative analyses using HPLC-DAD and the protein phosphatase inhibition assay. Furthermore, we were able to identify the presence of cyanobacterial non-ribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) genes in total DNA extracts from the mat community.
authors.affiliation: The School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
authors.forename: Anne-Dorothee
authors.initials: AD
authors.lastname: Jungblut
authors.forename: Stefan J
authors.initials: SJ
authors.lastname: Hoeger
authors.forename: Doug
authors.initials: D
authors.lastname: Mountfort
authors.forename: Bettina C
authors.initials: BC
authors.lastname: Hitzfeld
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Dietrich
authors.forename: Brett A
authors.initials: BA
authors.lastname: Neilan
mesh_terms: D000818:Animals; D000864:Antarctic Regions; D001427:Bacterial Toxins / Q000096:biosynthesis* / Q000737:chemistry / Q000633:toxicity; D018533:Biomass; D002851:Chromatography, High Pressure Liquid; D000458:Cyanobacteria / Q000378:metabolism*; D004269:DNA, Bacterial / Q000737:chemistry; D005618:Fresh Water; D052998:Microcystins; D010456:Peptides, Cyclic / Q000096:biosynthesis* / Q000737:chemistry / Q000633:toxicity; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors; D016133:Polymerase Chain Reaction
chemical_list: D001427:Bacterial Toxins; D004269:DNA, Bacterial; D052998:Microcystins; D010456:Peptides, Cyclic; C078588:microcystin; D010749:Phosphoprotein Phosphatases