title: Phylogenetic, chemical and morphological diversity of cyanobacteria from Portuguese temperate estuaries.
abstract: Cyanobacteria from estuarine habitats have been poorly studied regarding diversity and potential bioactive compounds production compared with their fresh and marine waters' congeners. In this work, 44 cyanobacteria isolates characterised from three Portuguese estuarine environments. Identification was performed based on diacritical morphological features of the isolates (e.g. cell shape, cell size, presence/absence of sheaths) and on 16S rRNA gene sequences phylogenetic analysis. Diversity of produced secondary metabolites was assessed by molecular and analytical tools. The isolates (mostly benthic forms) belonged to: (i) Chroococcales (Cyanobium, Synechocystis and Synechococcus), (ii) Oscillatoriales (Leptolyngbya, Microcoleus, Phormidium and Romeria) and (iii) Nostocales (Nostoc and Nodularia). 19 morphotypes were assigned at the species level, while phylogeny allowed us to distinguish 21 phylotypes spread amongst three distinct large clades. McyA and sxtI gene fragments were detected in some isolates, despite absence of toxins. Simultaneous presence of anabaenopeptins A and D was for the first time identified in Nostoc (LEGE06077). No correlation between morphological/phylogenetic relationships and the secondary-metabolite profile of the isolates was found. This is the first comprehensive study of estuarine cyanobacteria of Portuguese habitats revealing a diverse array of cyanobacteria that constitute an important source of potential bioactive compounds with ecological relevance and/or biomedical application.
authors.affiliation: CIIMAR/CIMAR-Laboratory of Ecotoxicology, Genomic and Evolution-Centre of Environmental and Marine Research, University of Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal. vlopes@ciimar.up.pt
authors.forename: Viviana R
authors.initials: VR
authors.lastname: Lopes
authors.forename: Vitor
authors.initials: V
authors.lastname: Ramos
authors.forename: António
authors.initials: A
authors.lastname: Martins
authors.forename: Marcos
authors.initials: M
authors.lastname: Sousa
authors.forename: Martin
authors.initials: M
authors.lastname: Welker
authors.forename: Agostinho
authors.initials: A
authors.lastname: Antunes
authors.forename: Vítor M
authors.initials: VM
authors.lastname: Vasconcelos
mesh_terms: D044822:Biodiversity; D000458:Cyanobacteria / Q000737:chemistry / Q000145:classification / Q000235:genetics; D017753:Ecosystem; D019015:Geologic Sediments / Q000382:microbiology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D011174:Portugal; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014871:Water Microbiology
chemical_list: D012336:RNA, Ribosomal, 16S