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Heterocytous cyanobacteria are among the most prolific sources of bioactive secondary metabolites, including anabaenopeptins (APTs). A terrestrial filamentous Brasilonema sp. CT11 collected in Costa Rica bamboo forest as a black mat, was studied using a multidisciplinary approach: genome mining and HPLC-HRMS/MS coupled with bioinformatic analyses. Herein, we report the nearly complete genome consisting of 8.79 Mbp with a GC content of 42.4%. Moreover, we report on three novel tryptophan-containing APTs; anabaenopeptin 788 (1), anabaenopeptin 802 (2), and anabaenopeptin 816 (3). Furthermore, the structure of two homologues, i.e., anabaenopeptin 802 (2a) and anabaenopeptin 802 (2b), was determined by spectroscopic analysis (NMR and MS). Both compounds were shown to exert weak to moderate antiproliferative activity against HeLa cell lines. This study also provides the unique and diverse potential of biosynthetic gene clusters and an assessment of the predicted chemical space yet to be discovered from this genus.

Background and aims – Phytoplankton samples were taken from a periodic, small and very shallow former clay-pit pond in eastern Poland near Lublin city. Diversity of the euglenophyte community was assessed during the period 2002–2004 and in 2014. Methods – Water samples were collected with a 20 µm plankton net and with a slime aspirator (20 ml capacity) from the surface of the bottom. One aliquot of each sample was fixed for SEM observation; the fresh part of the sample was analysed using light microscope. Physical and chemical properties of the water (pH, temperature, conductivity, phosphates and ammonium salt contents) were measured. Diversity indices were calculated (Shannon-Wiener, evenness, Margalef and Simpson) and UPGMA cluster analysis was applied to discern differences among euglenoid assemblages.Key results – In total, 63 euglenophyte taxa were found. The euglenophyte community was dominated by species belonging to the Trachelomonas genus (29 taxa). The most abundant and constant component were widespread and common species such as T. caudata, T. hispida, T. intermedia, T. volvocina and T. volvocinopsis. They usually occurred in very high densities. We also found some rarely reported euglenophytes including Euglena granulata, Trachelomonas lemmermannii, and T. sydneyensis. Conclusions – Euglenophytes were, with a few exceptions, the only group inhabiting the pond. Representatives of other groups such as diatoms or Scenedesmus species were recorded only occasionally. Nearly half of the taxa that were recorded in the first period (2002–2004) were found again after ten years. Of special concern was taxa belonging to the genus Trachelomonas. Trachelomonads, although known to represent taxa preferring waters moderately rich in nutrients, were very numerous in the investigated pond, which was enriched in phosphorus and nitrogen compounds.

This study brings results of a floristic survey of photosynthetic euglenoids. Data in this survey come from a floristic examination of more than 200 localities during the years 2008–2014 in combination with the literature data recorded from the end of 19th century to the present. In this work, 284 euglenoid taxa which belong to the genera Colacium (6 taxa), Cryptoglena (2 species), Discoplastis (1 species), Euglena (48 taxa), Euglenaformis (1 species), Euglenaria (3 species), Lepocinclis (36 taxa), Monomorphina (7 species), Phacus (71 taxa), Strombomonas (16 taxa) and Trachelomonas (93 taxa) are listed. Four categories of rarity were designed—common (52 taxa), rare (44 taxa), very rare (120 taxa) and data deficient (68 taxa). In checklist, ecological characteristics (colonized habitats, life strategy, level of rarity) of taxa are shown. Number of species is compared with several works from European countries (Hungary, Great Britain, Poland, Romania, Slovak Republic, Slovenia and Ukraine).  Taxonomic notes and new combinations reflecting recent works based on molecular-morphology are made and discussed. Results of this study bring next part to the knowledge of the Czech Republic algal flora.