Laucysteinamide A, a Hybrid PKS/NRPS Metabolite from a Saipan Cyanobacterium, cf. Caldora penicillata

A bioactivity guided study of a cf. Caldora penicillata species, collected during a 2013 expedition to the Pacific island of Saipan, Northern Mariana Islands (a commonwealth of the USA), led to the isolation of a new thiazoline-containing alkaloid, laucysteinamide A (1). Laucysteinamide A is a new monomeric analogue of the marine cyanobacterial metabolite, somocystinamide A (2), a disulfide-bonded dimeric compound that was isolated previously from a Fijian marine cyanobacterium. The structure and absolute configuration of laucysteinamide A (1) was determined by a detailed analysis of its NMR, MS, and CD spectra. In addition, the highly bioactive lipid, curacin D (3), was also found to be present in this cyanobacterial extract. The latter compound was responsible for the potent cytotoxicity of this extract to H-460 human non-small cell lung cancer cells in vitro

A novel uncultured heterotrophic bacterial associate of the cyanobacterium Moorea producens JHB

Background Filamentous tropical marine cyanobacteria such as Moorea producens strain JHB possess a rich community of heterotrophic bacteria on their polysaccharide sheaths; however, these bacterial communities have not yet been adequately studied or characterized. Results and discussion Through efforts to sequence the genome of this cyanobacterial strain, the 5.99 MB genome of an unknown bacterium emerged from the metagenomic information, named here as Mor1. Analysis of its genome revealed that the bacterium is heterotrophic and belongs to the phylum Acidobacteria, subgroup 22; however, it is only 85 % identical to the nearest cultured representative. Comparative genomics further revealed that Mor1 has a large number of genes involved in transcriptional regulation, is completely devoid of transposases, is not able to synthesize the full complement of proteogenic amino acids and appears to lack genes for nitrate uptake. Mor1 was found to be present in lab cultures of M. producens collected from various locations, but not other cyanobacterial species. Diverse efforts failed to culture the bacterium separately from filaments of M. producens JHB. Additionally, a co-culturing experiment between M. producens JHB possessing Mor1 and cultures of other genera of cyanobacteria indicated that the bacterium was not transferable. Conclusion The data presented support a specific relationship between this novel uncultured bacterium and M. producens, however, verification of this proposed relationship cannot be done until the ?uncultured? bacterium can be cultured

Credneramides A and B: Neuromodulatory Phenethylamine and Isopentylamine Derivatives of a Vinyl Chloride-Containing Fatty Acid from cf. Trichodesmium sp. nov.

Credneramides A (1) and B (2), two vinyl chloride-containing metabolites, were isolated from a Papua New Guinea collection of cf. Trichodesmium sp. nov. and expand a recently described class of vinyl chloride-containing natural products. The precursor fatty acid, credneric acid (3), was isolated from both the aqueous and organic fractions of the parent fraction as well as from another geographically and phylogenetically distinct cyanobacterial collection (Panama). Credneramides A and B inhibited spontaneous calcium oscillations in murine cerebrocortical neurons at low micromolar concentrations (1, IC 50 4.0 μM; 2, IC 50 3.8 μM).Credneramides A (1) and B (2), two vinyl chloride-containing metabolites, were isolated from a Papua New Guinea collection of cf. Trichodesmium sp. nov. and expand a recently described class of vinyl chloride-containing natural products. The precursor fatty acid, credneric acid (3), was isolated from both the aqueous and organic fractions of the parent fraction as well as from another geographically and phylogenetically distinct cyanobacterial collection (Panama). Credneramides A and B inhibited spontaneous calcium oscillations in murine cerebrocortical neurons at low micromolar concentrations (1, IC 50 4.0 μM; 2, IC 50 3.8 μM)

Coibacins A D, Antileishmanial Marine Cyanobacterial Polyketides with Intriguing Biosynthetic Origins

Four unsaturated polyketide lactone derivatives, coibacins A-D, were isolated from a Panamanian marine cyanobacterium, cf. Oscillatoria sp. The two different types of termini observed in these co-occurring metabolites, either a methyl cyclopropyl ring as seen in curacin A or a methyl vinyl chloride similar to that observed in the jamaicamides, suggest an intriguing flexibility in the “beta branch” forming biosynthetic process. The coibacins possess selective antileishmanial activity as well as potent anti-inflammatory activity.Four unsaturated polyketide lactone derivatives, coibacins A-D, were isolated from a Panamanian marine cyanobacterium, cf. Oscillatoria sp. The two different types of termini observed in these co-occurring metabolites, either a methyl cyclopropyl ring as seen in curacin A or a methyl vinyl chloride similar to that observed in the jamaicamides, suggest an intriguing flexibility in the “beta branch” forming biosynthetic process. The coibacins possess selective antileishmanial activity as well as potent anti-inflammatory activity

Working Group on Marine Mammal Ecology (WGMME)

159 pages.-- This work is licensed under the Creative Commons Attribution 4.0 International License (CC BY 4.0)The Working Group on Marine Mammal Ecology met in 2022 to address five terms of reference. Under the first of these, ToR A, new information on cetacean and seal population abundance, distribution, population/stock structure, was reviewed, including information on vagrant ma-rine mammal species. This was done to ensure the recording of possible range changes in marine mammal species in the future. For cetaceans, an update is given for the different species, providing for a latest estimate for all species studies. In this report, particular attention is given to the updating of information from Canadian and US waters, and together with those countries, latest estimates for cetacean species are provided. For seals, latest monitoring results are given for harbour, grey and Baltic ringed seals. In addition, where possible, local long-term trends are illustrated for those species, based on earlier WGMME efforts to assemble these data into the WGMME seal database. For both spe-cies’ groups, a first account of vagrant species is providedN

Sharing and community curation of mass spectrometry data with Global Natural Products Social Molecular Networking

The potential of the diverse chemistries present in natural products (NP) for biotechnology and medicine remains untapped because NP databases are not searchable with raw data and the NP community has no way to share data other than in published papers. Although mass spectrometry techniques are well-suited to high-throughput characterization of natural products, there is a pressing need for an infrastructure to enable sharing and curation of data. We present Global Natural Products Social molecular networking (GNPS, http://gnps.ucsd.edu), an open-access knowledge base for community wide organization and sharing of raw, processed or identified tandem mass (MS/MS) spectrometry data. In GNPS crowdsourced curation of freely available community-wide reference MS libraries will underpin improved annotations. Data-driven social-networking should facilitate identification of spectra and foster collaborations. We also introduce the concept of ‘living data’ through continuous reanalysis of deposited data

Novel Biodiversity of Natural Products-Producing Tropical Marine Cyanobacteria

During the last three decades, tropical marine cyanobacteria have emerged as an extraordinarily prolific source of promising biomedical natural products (NPs). Creative endeavors have been used to explore this novel chemical diversity, but lagging behind is the recognition and description of the biological diversity responsible for these NPs. Instead of being recognized as unique taxa, tropical marine NP-producing groups have been identified, with few exceptions, based on classification systems tied to morphospecies of terrestrial and freshwater specimens from temperate regions. This lack of proper classification systems is primarily due to the fact that tropical marine cyanobacteria have only recently been explored. As a result, our current perspective of the taxonomic origin and distribution of NPs in marine cyanobacteria is extraordinarily incomplete.A major aspect of this thesis research has focused on providing a better understanding of how NPs are distributed among different cyanobacterial groups so as to improve the efficiency of future investigations. The initial perception was that bioactive secondary metabolites are unequally distributed among different taxonomic groups with a few groups being responsible for the majority of the isolated NPs. However, based on polyphasic characterization of globally distributed populations, many of the most chemically prolific groups were found to constitute polyphyletic groups. Moreover, a large proportion of the secondary metabolites attributed to these groups are in fact produced by morphologically similar but evolutionarily distant cyanobacteria. I argue that this morphological resemblance of different cyanobacterial lineages is a major reason why some cyanobacterial groups have such an apparent richness of secondary metabolites.In my efforts to provide taxonomic clarity as well as to better guide future natural product drug discovery investigations, I have proposed a revision of the NP-rich genus Lyngbya on the basis of phylogenetic, genomic, secondary metabolism and ultrastructural comparisons with the genus reference strain PCC 7419T. In conclusion, this proposed revision of "tropical marine Lyngbya" as a new genus (Mooreagen. nov.) highlights the underestimated biodiversity of tropical marine cyanobacteria

Novel biodiversity of natural products-producing tropical marine cyanobacteria

During the last three decades, tropical marine cyanobacteria have emerged as an extraordinarily prolific source of promising biomedical natural products (NPs). Creative endeavors have been used to explore this novel chemical diversity, but lagging behind is the recognition and description of the biological diversity responsible for these NPs. Instead of being recognized as unique taxa, tropical marine NP-producing groups have been identified, with few exceptions, based on classification systems tied to morphospecies of terrestrial and freshwater specimens from temperate regions. This lack of proper classification systems is primarily due to the fact that tropical marine cyanobacteria have only recently been explored. As a result, our current perspective of the taxonomic origin and distribution of NPs in marine cyanobacteria is extraordinarily incomplete. A major aspect of this thesis research has focused on providing a better understanding of how NPs are distributed among different cyanobacterial groups so as to improve the efficiency of future investigations. The initial perception was that bioactive secondary metabolites are unequally distributed among different taxonomic groups with a few groups being responsible for the majority of the isolated NPs. However, based on polyphasic characterization of globally distributed populations, many of the most chemically prolific groups were found to constitute polyphyletic groups. Moreover, a large proportion of the secondary metabolites attributed to these groups are in fact produced by morphologically similar but evolutionarily distant cyanobacteria. I argue that this morphological resemblance of different cyanobacterial lineages is a major reason why some cyanobacterial groups have such an apparent richness of secondary metabolites. In my efforts to provide taxonomic clarity as well as to better guide future natural product drug discovery investigations, I have proposed a revision of the NP-rich genus Lyngbya on the basis of phylogenetic, genomic, secondary metabolism and ultrastructural comparisons with the genus reference strain PCC 7419T. In conclusion, this proposed revision of "tropical marine Lyngbya"as a new genus (Moorea gen. nov.) highlights the underestimated biodiversity of tropical marine cyanobacteri