Publicações
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Endozoicomonas lisbonensis sp. nov., a novel marine bacterium isolated from the soft coral Litophyton sp. at Oceanário de Lisboa in Portugal
Daniela M. G. da Silva, Matilde Marques, Joana F. Couceiro, Elsa Santos, Núria Baylina, Rodrigo Costa and Tina Keller-Costa
Abstract: This study describes a Gram-stain-negative, rod-shaped, facultatively anaerobic bacterial species isolated from the octocoral Litophyton sp. inhabiting the live coral aquarium at Oceanário de Lisboa in Portugal. Four strains, NE35, NE40T, NE41 and NE43, were classified into the genus Endozoicomonas by means of 16S rRNA gene and whole-genome sequence homologies. We then performed phylogenetic, phylogenomic and biochemical analyses to examine their novel species status within the Endozoicomonas genus, based on comparisons with the designated novel type strain NE40T. The closest 16S rRNA gene relatives to strain NE40T are Endozoicomonas montiporae CL-33T (98.2%), Endozoicomonas euniceicola EF212T (97.6%) and Endozoicomonas gorgoniicola PS125T (97.2%). The four strains show genome-wide average nucleotide identity scores above the species level cut-off (95%) with one another and below the cut-off with all Endozoicomonas type strains with publicly available genomes. Digital DNA–DNA hybridization further supported the classification of the strains as a novel species, showing values below 70% when compared with other Endozoicomonas type strains. The DNA G+C content of NE40T was 49.0 mol%, and its genome size was 5.45 Mb. Strain NE40T grows from 15 to 37 °C, with 1–5% (w/v) NaCl, and between pH 6.0 and 8.0 in marine broth and shows optimal growth at 28–32 °C, 2–3% NaCl and pH 7.0–8.0. The predominant cellular fatty acids are summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c), summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c), C16 :0 and C14 :0. Strain NE40T presents oxidase, catalase and β-galactosidase activities and can reduce nitrates to nitrites and degrade cellulose, chitin, agarose and xylan. Based on the polyphasic approach employed in this study, we propose the novel species name Endozoicomonas lisbonensis sp. nov. (type strain NE40T=DSM 118084T=UCCCB 212T).
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Beyond Restoration: Coral Microbiome Biotechnology
Joana F. Couceiro, Rodrigo Costa & Tina Keller-Costa
Abstract: Coral-associated microorganisms harbour an impressive and diverse secondary metabolite biosynthesis capacity with novel bioactive compounds being reported every year. The need of the coral holobiont to combat predation, overgrowth, and fouling presumably led to the ability of coral-associated microbes to produce different classes of compounds with a broad spectrum of activities. Although the precise ecological functions of most compounds from coral-associated microbes remain unknown or unproven, the biotechnological applications and prospective benefits of their exploitation are at hand. Bioactivities of pharmaceutical and industrial interest of coral symbiont-derived compounds include antitumoral, antibacterial, antifungal, antifouling, anti-inflammatory, and antidiabetic properties among many others, indicating vast potential for blue biotechnology and blue pharma. Moreover, coral-derived microorganisms often produce enzymes which can be employed in bioindustrial processes or for bioremediation purposes, for instance, in oil spills. This chapter reviews new natural products from coral symbionts reported between the years 2018 and 2022, highlighting the versatility and economic potential of this unique chemical reservoir. More than 385 novel compounds were described from coral-associated microbes in the past 5 years, 75% of them from octocoral (Octocorallia) symbionts. Over 87% of the compounds derive from coral-associated fungi of the Ascomycota phylum while only about 12% come from bacterial associates in the phyla Actinomycetota, Pseudomonadota, Bacillota and Cyanobacteria. Terpenes, alkaloids, peptides, and polyketides are the most prominent compound classes, many of which show anticancer, antibacterial, antifungal and antidiabetic activities. Despite the wide compound range described in coral-associated microorganisms, this chapter unveils that most of the lately applied research efforts target only certain microbial groups, such as actinomycetes and fungi, or specific geographical locations (e.g., South China Sea) and coral species. It reveals corals as a warehouses of microbes with bioactive potential similar to what is known from marine sponges. This largely untapped reservoir of novel natural products from coral-associated microbes is yet to be unlocked in future biodiscovery programs. We thus call on the scientific community to expand the scope of their coming research, directing it towards less explored groups such as cold-water corals and non-actinomycete bacterial symbionts. We also suggest a stronger integration of metagenomics libraries, synthetic biology, and heterologous expression approaches to access the chemical space of unculturable coral symbionts, as well as, the inclusion of new cultivation strategies, such as the iChip, for a more comprehensive, polyphasic approach.
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The Description of the Extremophile Reticulonema bolivianum gen. et sp. nov. (Microcoleaceae, Cyanobacteria) and the Review of the Phylogenetic Status of the Genus Capilliphycus Based on the 16S rRNA Gene
Guilherme Scotta Hentschke, Claudia Hoepfner, Daniel Guzmán and Vitor M. Vasconcelos
Abstract: This article describes a new genus and species of cyanobacteria isolated from Laguna Pastos Grandes in the Bolivian Altiplano. This discovery marks the first described species of this phylum from this extreme environment. Additionally, the phylogenetic status of the genus Capilliphycus is reassessed. The analyses are based on 16S rRNA gene maximum likelihood and Bayesian phylogenies, identity (p-distance), morphology and habitat comparisons. The new genus is a Lyngbya-like type from a mat at the margin of a brackish–alkaline lake with borax. It is phylogenetically close to Dapis, Tenebriella and Okeania, but compared to these genera, the maximum 16S rRNA gene identity values reached only 90.9%, 91.1% and 92.5%, respectively. The genus Capilliphycus was found to be polyphyletic. The type species Capilliphycus salinus is clustered with C. guerandensis. However, “C. tropicalis” and “C. flaviceps” form a distinct clade, distant from the Capilliphycus type species. Between the two “Capilliphycus” clades, Sirenicapillaria and Limnoraphis are found.
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Taxonomic updates in the family Leptolyngbyaceae (Leptolyngbyales,Cyanobacteria): the description of Pseudoleptolyngbya gen. nov, Leptolyngbyopsisgen. nov., and the replacement of Arthronema
Guilherme Scotta Hentschke, João Morais, Flavio Luis de Oliveira, Raquel Silva, Pedro Cruz, Vitor Vasconcelos
Abstract: In this paper, we used the polyphasic approach combining 16S rRNA gene phylogenies, identity (p-distance), 16S-23S ITSsecondary structures, and morphological and habitat analyses to describe two new genera of Leptolyngbyaceae,Pseudoleptolynbgya G.S. Hentschke gen. nov. (based on LEGE 16533 and LEGE 16651) and Leptolyngbyopsis G.S.Hentschke gen. nov. (based on LEGE 16524). These strains were sampled from freshwater environments at Figueira daFoz, Monchique and Coimbra, Portugal. Both genera are morphologically and ecologically identical to Leptolyngbya andcan only be distinguished from it by molecular analyses. Based on morphological and ITS secondary structure analyses wedescribe two species of Pseudoleptolyngbya, P. figueirensis and P. monchiquensis. P. figueirensis differs fromP. monchiquensis by the denser arrangement of the trichomes, the presence of firm sheaths, the common formation ofshorter trichomes (up to 30 cells), and the olive or yellowish-green cell content, which is darker in P. monchiquensis.Moreover, the macroscopic appearance of P. figueirensis is a dense brownish mat, while P. monchiquensis is less dense andreddish. 16S rRNA gene sequences of Arthronema africanum CCALA020 are > 99% identical to Leptolyngbya boryanaPCC6306, so we transfer A. africanum to Leptolyngbya, as L. africanoidea.
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Genome sequences of four novel Endozoicomonas strains associated with a tropical octocoral in a long-term aquarium facility
Matilde Marques, Daniela M.G. da Silva, Elsa Santos, Núria Baylina, Raquel Peixoto, Nikos C. Kyrpides , Tanja Woyke , William B. Whitman, Tina Keller-Costa , Rodrigo Costa
Abstract: We report the genome sequences of four Endozoicomonas sp. strains isolated from the octocoral Litophyton maintained long term at an aquarium facility. Our analysis reveals the coding potential for versatile polysaccharide metabolism; Type II, III, IV, and VI secretion systems; and the biosynthesis of novel ribosomally synthesized and post-translationally modified peptides.
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Genome-based in silico assessment of biosynthetic gene clusters in Planctomycetota: Evidences of its wide divergent nature
Rita Calisto, Ofélia Godinho, Damien P. Devos, Olga M. Lage
Abstract: The biotechnological potential of Planctomycetota only recently started to be unveiled. 129 reference genomes and 5194 available genomes (4988 metagenome-assembled genomes (MAGs)) were analysed regarding the presence of Biosynthetic Gene Clusters (BGCs). By antiSMASH, 987 BGCs in the reference genomes and 22,841 BGCs in all the available genomes were detected. The classes Ca Uabimicrobiia, Ca Brocadiia and Planctomycetia had the higher number of BGC per genome, while Phycisphaerae had the lowest number. The most prevalent BGCs found in Planctomycetota reference genomes were terpenes, NRPS, type III PKS, type I PKS. As much as 88 % of the predicted regions had no similarity with known clusters in MIBiG database. This study strengthens the uniqueness of Planctomycetota for the isolation of new compounds and provide an overview of BGCs taxonomic distribution and of the type of predicted product. This outline allows the acceleration and focus of the research on drug discovery in Planctomycetota.
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Genome sequence of the marine alphaproteobacterium Lentilitoribacter sp. EG35 isolated from the temperate octocoral Eunicella gazella
Tina Keller-Costa, Selene Madureira, Ana S. Fernandes, Lydia Kozma, Jorge M.S. Gonçalves, Cristina Barroso, Conceição Egas, Rodrigo Costa
Abstract: We report the genome sequence of Lentilitoribacter sp. strain EG35 isolated from the octocoral Eunicella gazella sampled off the coast of Portugal. We reveal the coding potential for the biosynthesis of polyhydroxyalkanoates — biodegradable polyesters that may serve bioplastics production, diverse homoserine lactone-like communication signals, and four putatively novel natural products.
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Carotenoids from cyanobacteria modulate iNOS and inhibit the production of inflammatory mediators: Promising agents for the treatment of inflammatory conditions
Janaína Morone, Guilherme Hentschke, Eugénia Pinto, João Morais, Pedro Cruz, Vitor Vasconcelos, Rosário Martins, Graciliana Lopes
Abstract: Cyanobacteria are green multiproduct refineries of increasing interest for different industrial prospects. In this work, eleven cyanobacteria strains isolated from the Cape Verde archipelago were explored for their biotechnological applications in the field of inflammation. A biorefinery approach was employed to produce carotenoidtargeted extracts, further profiled by HPLC-PDA and explored for their ability to i) scavenge important physiological free radicals of oxygen (superoxide anion radical, O2•-) and nitrogen (nitric oxide, •NO) involved in the inflammatory process ii) slow-down post-inflammatory hyperpigmentation and iii) modulate the activity of inflammatory cytokine-producing enzymes, in enzymatic and cell systems comprising RAW 264.7 cells. The studied strains turned out to be important carotenoid producers (70.47–186.71 μg mg 1dry extract), mainly represented by β-carotene and zeaxanthin. The targeted-extracts stood-out for their potential to slow-down the inflammatory process through a multitarget approach: scavenging •NO and O2•-, reducing inflammatory cytokines production through lipoxygenase inhibition, and modulating the inducible nitric oxide synthase in LPSstimulated RAW 264.7 cells, with strains of the order Nodosilineales revealing to be worth of further biotechnological exploitation.