Percorrer por autor "Marques, Matilde"
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- An artificial selection procedure enriches for known and suspected chitin degraders from the prokaryotic rare biosphere of multiple marine biotopesPublication . Meunier, Laurence; Keller-Costa, Tina; Cannella, David; Gonçalves, Jorge Manuel Santos; Dechamps, Etienne; Marques, Matilde; Costa, Rodrigo; George, Isabelle F.Biological of chitin-degrading microbial communities change across marine biotopes, but efforts to isolate chitin degraders within these communities in the laboratory have seldom been attempted. We characterized the prokaryotic communities associated with the marine sponge Sarcotragus spinosulus, the octocoral Eunicella labiata, and their surrounding sediment and seawater and applied an artificial selection procedure to enrich bacterial consortia capable of degrading chitin from the abovementioned biotopes. Throughout the procedure, chitin degradation was monitored, and the taxonomic composition was studied along four successive enrichment cultures from each biotope. Results The naturally occurring prokaryotic communities of the two host species (Sarcotragus spinosulus and Eunicella labiata) were distinct from each other and from those of seawater and sediments, even though they were co-inhabiting the same geographic area. We found that low-abundance bacteria from the rare biosphere were recruited in the enrichment cultures from all biotopes, while dominant bacterial symbionts likely to play a role in chitin degradation within marine sponges and octocorals remained “unculturable” under our experimental conditions. Well-known chitin degraders such as Vibrio, Pseudoalteromonas and Aquimarina, as well as other taxa not known or poorly known for their role(s) in chitin degradation such as Aureivirga, Halodesulfovibrio, Motilimonas, Muricauda, Psychromonas, Poseidonibacter, Reichenbachiella, and Thalassotalea, among others, were enriched using our artificial selection approach. Distinct chitin-degrading consortia were enriched from each marine biotope, highlighting the feasibility of this approach in fostering the discovery of novel microorganisms and enzymes involved in chitin degradation pathways of relevance in applied biotechnology. Conclusion This study unveils distinct bacterial consortia possessing moderate to high efficiency at degrading chitin. They were composed of a mix of known chitin degraders, known chitin utilizers and many taxa poorly or not yet known for their role(s) in chitin degradation such as Aureivirga, Psychromonas, Motilimonas, Reichenbachiella, or Halodesulfovibrio. The latter taxa are potential key players in marine chitin degradation whose study could lead to the discovery of novel enzyme variants able to degrade chitin and its derivatives.
- Marine sponge and octocoral-associated bacteria show versatile secondary metabolite biosynthesis potential and antimicrobial activities against human pathogensPublication . Almeida, João F.; Marques, Matilde; Oliveira, Vanessa; Egas, Conceição; Mil-Homens, Dalila; Viana, Romeu; Cleary, Daniel F. R.; Huang, Yusheng M.; Fialho, Arsénio M.; Teixeira, Miguel C.; Gomes, Newton C. M.; Costa, Rodrigo; Keller-Costa, TinaMarine microbiomes are prolific sources of bioactive natural products of potential pharmaceutical value. This study inspected two culture collections comprising 919 host-associated marine bacteria belonging to 55 genera and several thus-far unclassified lineages to identify isolates with potentially rich secondary metabolism and antimicrobial activities. Seventy representative isolates had their genomes mined for secondary metabolite biosynthetic gene clusters (SM-BGCs) and were screened for antimicrobial activities against four pathogenic bacteria and five pathogenic Candida strains. In total, 466 SM-BGCs were identified, with antimicrobial peptide- and polyketide synthase-related SM-BGCs being frequently detected. Only 38 SM-BGCs had similarities greater than 70% to SM-BGCs encoding known compounds, highlighting the potential biosynthetic novelty encoded by these genomes. Cross-streak assays showed that 33 of the 70 genome-sequenced isolates were active against at least one Candida species, while 44 isolates showed activity against at least one bacterial pathogen. Taxon-specific differences in antimicrobial activity among isolates suggested distinct molecules involved in antagonism against bacterial versus Candida pathogens. The here reported culture collections and genome-sequenced isolates constitute a valuable resource of understudied marine bacteria displaying antimicrobial activities and potential for the biosynthesis of novel secondary metabolites, holding promise for a future sustainable production of marine drug leads.
- Metagenome-assembled genome sequences of three uncultured planktomarina sp. strains from the Northeast Atlantic OceanPublication . Marques, Matilde; Borges, Nuno; Silva, Sandra Godinho; da Rocha, Ulisses Nunes; Lago-Lestón, Asunción; Keller-Costa, Tina; Da Silva Costa, RodrigoWe report three metagenome-assembled genomes (MAGs) of Planktomarina strains from coastal seawater (Portugal) to help illuminate the functions of understudied Rhodobacteraceae bacteria in marine environments. The MAGs encode proteins involved in aerobic anoxygenic photosynthesis and a versatile carbohydrate metabolism, strengthening the role of Planktomarina species in oceanic carbon cycling.
- The Roseibium album (Labrenzia alba) genome possesses multiple symbiosis factors possibly underpinning host-microbe relationships in the Marine BenthosPublication . Couceiro, Joana Fernandes; Keller-Costa, Tina; Marques, Matilde; Kyrpides, Nikos C.; Woyke, Tanja; Whitman, William B.; Costa, RodrigoHere, we announce the genomes of eight Roseibium album (synonym Labrenzia alba) strains that were obtained from the octocoral Eunicella labiata. Genome annotation revealed multiple symbiosis factors common to all genomes, such as eukaryotic-like repeat protein- and multidrug resistance-encoding genes, which likely underpin symbiotic relationships with marine invertebrate hosts.