title: Morphologic, Phylogenetic and Chemical Characterization of a Brackish Colonial Picocyanobacterium (Coelosphaeriaceae) with Bioactive Properties.
abstract: Despite their cosmopolitan distribution, knowledge on cyanobacteria in the family Coelosphaeriaceae is limited. In this study, a single species culture of a coelosphaeran cyanobacterium isolated from a brackish rock pool in the Baltic Sea was established. The strain was characterized by morphological features, partial 16S rRNA sequence and nonribosomal oligopeptide profile. The bioactivity of fractionated extracts against several serine proteases, as well as protein-serine/threonine phosphatases was studied. Phylogenetic analyses of the strain suggested a close relationship with Snowella litoralis, but its morphology resembled Woronichinia compacta. The controversial morphologic and phylogenetic results demonstrated remaining uncertainties regarding species division in this cyanobacteria family. Chemical analyses of the strain indicated production of nonribosomal oligopeptides. In fractionated extracts, masses and ion fragmentation spectra of seven possible anabaenopeptins were identified. Additionally, fragmentation spectra of cyanopeptolin-like peptides were collected in several of the fractions. The nonribosomal oligopeptide profile adds another potential identification criterion in future inter- and intraspecies comparisons of coelosphaeran cyanobacteria. The fractionated extracts showed significant activity against carboxypeptidase A and trypsin. Inhibition of these important metabolic enzymes might have impacts at the ecosystem level in aquatic habitats with high cyanobacteria densities.
authors.affiliation: Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Artillerigatan 6A, Åbo 20520, Finland. kerstin.haggqvist@abo.fi.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Häggqvist
authors.affiliation: Department of Marine Biotechnology, Institute of Oceanography, University of Gdańsk, Al. Marszałka Piłsudskiego 46, Gdynia 81-378, Poland. anna.torunska@ug.edu.pl.
authors.forename: Anna
authors.initials: A
authors.lastname: Toruńska-Sitarz
authors.affiliation: Department of Marine Biotechnology, Institute of Oceanography, University of Gdańsk, Al. Marszałka Piłsudskiego 46, Gdynia 81-378, Poland. agata.blaszczyk@ug.edu.pl.
authors.forename: Agata
authors.initials: A
authors.lastname: Błaszczyk
authors.affiliation: Department of Marine Biotechnology, Institute of Oceanography, University of Gdańsk, Al. Marszałka Piłsudskiego 46, Gdynia 81-378, Poland. biohm@ug.edu.pl.
authors.forename: Hanna
authors.initials: H
authors.lastname: Mazur-Marzec
authors.affiliation: Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Artillerigatan 6A, Åbo 20520, Finland. jussi.meriluoto@abo.fi.
authors.forename: Jussi
authors.initials: J
authors.lastname: Meriluoto
mesh_terms: D043422:Carboxypeptidases A / Q000037:antagonists & inhibitors; D002918:Chymotrypsin / Q000037:antagonists & inhibitors; D000458:Cyanobacteria / Q000235:genetics / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D009842:Oligopeptides / Q000302:isolation & purification / Q000494:pharmacology*; D010196:Pancreatic Elastase / Q000037:antagonists & inhibitors; D010802:Phylogeny; D054645:Protein Phosphatase 1 / Q000037:antagonists & inhibitors; D054648:Protein Phosphatase 2 / Q000037:antagonists & inhibitors; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D000068357:Saline Waters; D013917:Thrombin / Q000037:antagonists & inhibitors
chemical_list: D004269:DNA, Bacterial; D009842:Oligopeptides; D012336:RNA, Ribosomal, 16S; D054645:Protein Phosphatase 1; D054648:Protein Phosphatase 2; D043422:Carboxypeptidases A; D002918:Chymotrypsin; D010196:Pancreatic Elastase; D013917:Thrombin
keywords: Snowella; Woronichinia; anabaenopeptins; cyanopeptolins; enzyme inhibition; polyphasic approach