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1.
Environ Microbiol ; 26(4): e16620, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38627038

RESUMO

Actinomycetota, associated with macroalgae, remains one of the least explored marine niches. The secondary metabolism of Actinomycetota, the primary microbial source of compounds relevant to biotechnology, continues to drive research into the distribution, dynamics, and metabolome of these microorganisms. In this study, we employed a combination of traditional cultivation and metagenomic analysis to investigate the diversity of Actinomycetota in two native macroalgae species from the Portuguese coast. We obtained and taxonomically identified a collection of 380 strains, which were distributed across 12 orders, 15 families, and 25 genera affiliated with the Actinomycetia class, with Streptomyces making up approximately 60% of the composition. Metagenomic results revealed the presence of Actinomycetota in both Chondrus crispus and Codium tomentosum datasets, with relative abundances of 11% and 2%, respectively. This approach identified 12 orders, 16 families, and 17 genera affiliated with Actinomycetota, with minimal overlap with the cultivation results. Acidimicrobiales emerged as the dominant actinobacterial order in both macroalgae, although no strain affiliated with this taxonomic group was successfully isolated. Our findings suggest that macroalgae represent a hotspot for Actinomycetota. The synergistic use of both culture-dependent and independent approaches proved beneficial, enabling the identification and recovery of not only abundant but also rare taxonomic members.


Assuntos
Actinobacteria , Clorófitas , Alga Marinha , Humanos , Alga Marinha/microbiologia , Portugal , Bactérias
2.
Artigo em Inglês | MEDLINE | ID: mdl-38639738

RESUMO

A novel strain, MA3_2.13T, was isolated from deep-sea sediment of Madeira Archipelago, Portugal, and characterized using a polyphasic approach. This strain produced dark brown soluble pigments, bronwish black substrate mycelia and an aerial mycelium with yellowish white spores, when grown on GYM 50SW agar. The main respiratory quinones were MK-10(H4), MK-10(H6) and MK-10(H8). Diphosphatidylglycerol, phosphatidylethanolamine, three unidentified phospholipids and two glycophospholipids were identified as the main phospholipids. The major cellular fatty acids were iso-C16 : 1, iso-C16 : 0, anteiso-C17 : 1 and anteiso-C17 : 0. Phylogenetic analyses based on 16S rRNA gene showed that strain MA3_2.13T is a member of the genus Streptomyces and was most closely related to Streptomyces triticirhizae NEAU-YY642T (NR_180032.1; 16S rRNA gene similarity 97.9 %), Streptomyces sedi YIM 65188T (NR_044582.1; 16S rRNA gene similarity 97.4 %), Streptomyces mimosae 3MP-10T (NR_170412.1; 16S rRNA gene similarity 97.3 %) and Streptomyces zhaozhouensis NEAU-LZS-5T (NR_133874.1; 16S rRNA gene similarity 97.0 %). Genome pairwise comparisons with closest related type strains retrieved values below the threshold for species delineation suggesting that strain MA3_2.13T represents a new branch within the genus Streptomyces. Based on these results, strain MA3_2.13T (=DSM 115980T=LMG 33094T) is proposed as the type strain of a novel species of the genus Streptomyces, for which the name Streptomyces profundus sp. nov. is proposed.


Assuntos
Ácidos Graxos , Streptomyces , Ácidos Graxos/química , Análise de Sequência de DNA , Filogenia , RNA Ribossômico 16S/genética , Portugal , Microbiologia do Solo , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Fosfolipídeos/química
3.
Mar Drugs ; 22(6)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38921579

RESUMO

Bioprospecting the secondary metabolism of underexplored Actinomycetota taxa is a prolific route to uncover novel chemistry. In this work, we report the isolation, structure elucidation, and bioactivity screening of cellulamides A and B (1 and 2), two novel linear peptides obtained from the culture of the macroalga-associated Cellulosimicrobium funkei CT-R177. The host of this microorganism, the Chlorophyta Codium tomentosum, was collected in the northern Portuguese coast and, in the scope of a bioprospecting study focused on its associated actinobacterial community, strain CT-R177 was isolated, taxonomically identified, and screened for the production of antimicrobial and anticancer compounds. Dereplication of a crude extract of this strain using LC-HRMS(/MS) analysis unveiled a putative novel natural product, cellulamide A (1), that was isolated following mass spectrometry-guided fractionation. An additional analog, cellulamide B (2) was obtained during the chromatographic process and chemically characterized. The chemical structures of the novel linear peptides, including their absolute configurations, were elucidated using a combination of HRMS, 1D/2D NMR spectroscopy, and Marfey's analysis. Cellulamide A (1) was subjected to a set of bioactivity screenings, but no significant biological activity was observed. The cellulamides represent the first family of natural products reported from the Actinomycetota genus Cellulosimicrobium, showcasing not only the potential of less-explored taxa but also of host-associated marine strains for novel chemistry discovery.


Assuntos
Peptídeos , Humanos , Peptídeos/química , Peptídeos/farmacologia , Peptídeos/isolamento & purificação , Actinobacteria/química , Actinobacteria/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Organismos Aquáticos , Produtos Biológicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Linhagem Celular Tumoral , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação
4.
Crit Rev Biotechnol ; 42(7): 991-1009, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34615427

RESUMO

Fluorine-based agrochemicals have been benchmarked as the golden standard in pesticide development, prompting their widespread use in agriculture. As a result, fluorinated pesticides can now be found in the environment, entailing serious ecological implications due to their harmfulness and persistence. Microbial degradation might be an option to mitigate these impacts, though environmental microorganisms are not expected to easily cope with these fluoroaromatics due to their recalcitrance. Here, we provide an outlook on the microbial metabolism of fluorinated pesticides by analyzing the degradation pathways and biochemical processes involved, while also highlighting the central role of enzymatic defluorination in their productive metabolism. Finally, the potential contribution of these microbial processes for the dissipation of fluorinated pesticides from the environment is also discussed.


Assuntos
Inseticidas , Praguicidas , Agricultura , Flúor , Praguicidas/química , Praguicidas/metabolismo
5.
Antonie Van Leeuwenhoek ; 113(4): 459-475, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31720916

RESUMO

Salterns are extreme environments, where the high salt concentration is the main limitation to microbial growth, along with solar radiation, temperature and pH. These selective pressures might lead to the acquisition of unique genetic adaptations that can manifest in the production of interesting natural products. The present study aimed at obtaining the culturable microbial diversity from two Portuguese salterns located in different geographic regions. A total of 190 isolates were retrieved and identified as belonging to 30 genera distributed among 4 phyla-Firmicutes, Proteobacteria, Actinobacteria and Bacteroidetes. Specifically, members of the genus Bacillus were the most frequently isolated from both salterns and all actinobacterial isolates belong to the rare members of this group. The molecular screening of NRPS and PKS-I genes allowed the detection of 38 isolates presenting PKS-I, 25 isolates presenting NRPS and 23 isolates presenting both types of biosynthetic genes. Sequencing of randomly selected amplicons revealed similarity with known PKS-I and NRPS genes or non-annotated hypothetical proteins. This study is the first contribution on the culturable bacterial diversity of Portuguese salterns and on their bioactive potential. Ultimately, these findings provide a novel contribution to improve the understanding on the microbial diversity of salterns.


Assuntos
Bactérias/classificação , Bactérias/isolamento & purificação , Ecossistema , Microbiologia Ambiental , Técnicas Bacteriológicas , Portugal , Especificidade da Espécie
6.
J Environ Manage ; 231: 1145-1153, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30602239

RESUMO

This study aimed to investigate the potential of microbial communities from the rhizosediment of two plants - Phragmites australis and Juncus maritimus - occurring in an estuarine area subjected to a high anthropogenic impact, to biodegrade ENR, a commonly used veterinary antibiotic. An enrichment process with 1 mgL-1 of ENR was conducted during ca. 9 months, using acetate as a co-substrate. After this, the enriched microbial consortia were challenged with higher ENR concentrations of 2 and 3 mgL-1. Microbial cultures enriched with 1 mgL-1 of ENR were capable of biodegrading this antibiotic, though not completely. By the end of the enrichment phase, microbial cultures were defluorinating an average of 50% of the ENR supplemented. Higher ENR concentrations led to lower biodegradation performances, suggesting a possible toxic/inhibitory effect in the microbial cultures. Phylogenetic identification of the microorganisms isolated from microbial cultures enriched with ENR revealed a high taxonomical diversity, with microorganisms belonging mainly to Proteobacteria and Bacteroidetes phyla. Assemblage of the obtained isolated strains (according to the enriched cultures from which they were isolated) revealed that the resulting consortia were also capable of degrading ENR, indicating that the main microbial players in the biodegradation of this antibiotic were isolated. These consortia also showed to be more robust to degrade higher concentrations of ENR than the corresponding enriched cultures. This study shows that microorganisms derived from rhizosediments of the selected plants, exhibit capacity to biodegrade ENR, though not completely for the concentrations tested, and may be further explored for the development of bioremediation strategies for the treatment of this antibiotic.


Assuntos
Consórcios Microbianos , Poluentes Químicos da Água , Biodegradação Ambiental , Enrofloxacina , Filogenia , Áreas Alagadas
7.
Crit Rev Biotechnol ; 37(7): 880-897, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28049355

RESUMO

Fluorinated compounds are finding increasing uses in several applications. They are employed in almost all areas of modern society. These compounds are all produced by chemical synthesis and their abundance highly contrasts with fluorinated molecules of natural origin. To date, only some plants and a handful of actinomycetes species are known to produce a small number of fluorinated compounds that include fluoroacetate (FA), some ω-fluorinated fatty acids, nucleocidin, 4-fluorothreonine (4-FT), and the more recently identified (2R3S4S)-5-fluoro-2,3,4-trihydroxypentanoic acid. This largely differs from other naturally produced halogenated compounds, which totals more than 5000. The mechanisms underlying biological fluorination have been uncovered after discovering the first actinomycete species, Streptomyces cattleya, that is capable of producing FA and 4-FT, and a fluorinase has been identified as the enzyme responsible for the formation of the C-F bond. The discovery of this enzyme has opened new perspectives for the biotechnological production of fluorinated compounds and many advancements have been achieved in its application mainly as a biocatalyst for the synthesis of [18F]-labeled radiotracers for medical imaging. Natural fluorinated compounds may also be derived from abiogenic sources, such as volcanoes and rocks, though their concentrations and production mechanisms are not well known. This review provides an outlook of what is currently known about fluorinated compounds with natural origin. The paucity of these compounds and the biological mechanisms responsible for their production are addressed. Due to its relevance, special emphasis is given to the discovery, characterization and biotechnological potential of the unique fluorinase enzyme.


Assuntos
Proteínas de Bactérias/metabolismo , Oxirredutases/metabolismo , Halogenação , Streptomyces , Treonina/análogos & derivados
8.
Acta Paediatr ; 106(9): 1525-1530, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28394456

RESUMO

AIM: Protruding ears are a prevalent deformity, with a reported incidence of 5% in the paediatric population, but it lacks a simple digital classification. The aim of this study was to find a parameter that would objectively allow the photographic classification of protrusion, by comparing frontal facial images of patients with protruding ears with aged-matched controls. METHODS: This prospective cohort study compared the frontal facial images of 105 patients with protruding ears with 112 aged-matched controls without protruding ears. A rectangle was drawn on the image for each ear, encompassing its full visible anatomy. The width of each rectangle was divided by its height to create an index. The mean value of both ears was defined as the Frontal Aesthetics Translation Index for Measurement of Amplitude of the Ears (FATIMAE). RESULTS: The calculated values for group with protruding ears were significantly higher than for the controls. No gender differences were found. However, the FATIMAE values decreased with age, establishing different classification criteria for separate age groups. CONCLUSION: The FATIMAE is easy to calculate and implement in daily clinical practice and establishes a practical approach for classification of protrusion, as well as for referral criteria for a specialised surgical consultation.


Assuntos
Pavilhão Auricular/anormalidades , Adolescente , Criança , Pré-Escolar , Pavilhão Auricular/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Estudos Prospectivos , Valores de Referência , Índice de Gravidade de Doença
9.
J Sci Food Agric ; 97(13): 4379-4385, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28071807

RESUMO

BACKGROUND: Chickpea (Cicer arietinum L.) is a widely cropped pulse and an important source of proteins for humans. In Mediterranean regions it is predicted that drought will reduce soil moisture and become a major issue in agricultural practice. Nitrogen (N)-fixing bacteria and arbuscular mycorrhizal (AM) fungi have the potential to improve plant growth and drought tolerance. The aim of the study was to assess the effects of N-fixing bacteria and AM fungi on the growth, grain yield and protein content of chickpea under water deficit. RESULTS: Plants inoculated with Mesorhizobium mediterraneum or Rhizophagus irregularis without water deficit and inoculated with M. mediterraneum under moderate water deficit had significant increases in biomass. Inoculation with microbial symbionts brought no benefits to chickpea under severe water deficit. However, under moderate water deficit grain crude protein was increased by 13%, 17% and 22% in plants inoculated with M. mediterraneum, R. irregularis and M. mediterraneum + R. irregularis, respectively. CONCLUSION: Inoculation with N-fixing bacteria and AM fungi has the potential to benefit agricultural production of chickpea under water deficit conditions and to contribute to increased grain protein content. © 2017 Society of Chemical Industry.


Assuntos
Inoculantes Agrícolas/fisiologia , Fenômenos Fisiológicos Bacterianos , Cicer/microbiologia , Fungos/fisiologia , Micorrizas/fisiologia , Proteínas de Plantas/análise , Água/metabolismo , Bactérias/crescimento & desenvolvimento , Cicer/química , Cicer/crescimento & desenvolvimento , Cicer/metabolismo , Fungos/crescimento & desenvolvimento , Nitrogênio/metabolismo , Proteínas de Plantas/metabolismo , Simbiose , Água/análise
10.
J Toxicol Environ Health A ; 79(7): 320-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27077563

RESUMO

The widespread use of agrochemicals is detrimental to the environment and may exert harmful effects on human health. The consumer demand for organic food plants has been increasing. There is thus a rising need for alternatives to agrochemicals that can foster sustainable plant production. The aim of this study was to evaluate the potential use of an arbuscular mycorrhizal (AM) fungus as an alternative to application of chemical fertilizer for improving growth performance of the medicinal and aromatic plant Coriandrum sativum. Plants were inoculated with the AM fungus Rhizophagus irregularis BEG163 and/or supplemented with a commercial chemical fertilizer (Plant Marvel, Nutriculture Bent Special) in agricultural soil. Plant growth, nutrition, and development of AM fungus were assessed. Plants inoculated with R. irregularis and those supplemented with chemical fertilizer displayed significantly improved growth performances when compared with controls. There were no significant differences in total fresh weight between plants inoculated with R. irregularis or those supplemented with chemical fertilizer. Leaf chlorophyll a + b (82%), shoot nitrogen (44%), phosphorus (254%), and potassium (27%) concentrations increased in plants inoculated with R. irregularis compared to controls. Application of chemical fertilizer inhibited root mycorrhizal colonization and the length of the extraradical mycelium of R. irregularis. Inoculation with R. irregularis was equally or more efficient than application of chemical fertilizer in promoting growth and nutrition of C. sativum. AM fungi may thus contribute to improve biologically based production of food plants and reduce the dependence on agrochemicals in agriculture.


Assuntos
Coriandrum/microbiologia , Coriandrum/fisiologia , Fertilizantes/análise , Micorrizas/fisiologia , Microbiologia do Solo , Coriandrum/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Raízes de Plantas/fisiologia , Plantas Medicinais/crescimento & desenvolvimento , Plantas Medicinais/microbiologia , Plantas Medicinais/fisiologia
11.
Appl Microbiol Biotechnol ; 98(4): 1893-905, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23949994

RESUMO

A bacterial strain capable of aerobic degradation of 4-fluorocinnamic acid (4-FCA) as the sole source of carbon and energy was isolated from a biofilm reactor operating for the treatment of 2-fluorophenol. The organism, designated as strain S2, was identified by 16S rRNA gene analysis as a member of the genus Rhodococcus. Strain S2 was able to mineralize 4-FCA as sole carbon and energy source. In the presence of a conventional carbon source (sodium acetate [SA]), growth rate of strain S2 was enhanced from 0.04 to 0.14 h(-1) when the culture medium was fed with 0.5 mM of 4-FCA, and the time for complete removal of 4-FCA decreased from 216 to 50 h. When grown in SA-supplemented medium, 4-FCA concentrations up to 1 mM did not affect the length of the lag phase, and for 4-FCA concentrations up to 3 mM, strain S2 was able to completely remove the target fluorinated compound. 4-Fluorobenzoate (4-FBA) was transiently formed in the culture medium, reaching concentrations up to 1.7 mM when the cultures were supplemented with 3.5 mM of 4-FCA. Trans,trans-muconate was also transiently formed as a metabolic intermediate. Compounds with molecular mass compatible with 3-carboxymuconate and 3-oxoadipate were also detected in the culture medium. Strain S2 was able to mineralize a range of other haloorganic compounds, including 2-fluorophenol, to which the biofilm reactor had been exposed. To our knowledge, this is the first time that mineralization of 4-FCA as the sole carbon source by a single bacterial culture is reported.


Assuntos
Cinamatos/metabolismo , Rhodococcus/metabolismo , Biofilmes , Reatores Biológicos/microbiologia
12.
Methods Enzymol ; 696: 321-338, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38658086

RESUMO

Research on microbial defluorination is largely centred on controlled experiments using axenic or well defined microbial inocula. These approaches serve a relevant purpose in the field, offering fundamental biochemical and mechanistic insights on the intricacies of biological defluorination. However, they fail to account for the effective contribution of environmental microbial communities in the recycling of fluoroorganic pollutants, a highly relevant perspective from an environmental risk assessment standpoint, while also missing an important outlook on how community-wide dynamics can leverage the breakdown of C─F bonds in these recalcitrant compounds. With that in mind, this chapter provides experimental and methodological insights on the study of microbial defluorination in wild environmental communities, using this critical catabolic step as the de facto endpoint to evolve, select and cultivate microorganisms with improved defluorination performances.


Assuntos
Biodegradação Ambiental , Bactérias/metabolismo , Bactérias/genética , Poluentes Ambientais/metabolismo , Halogenação , Microbiologia Ambiental , Microbiota , Flúor/metabolismo , Flúor/química
13.
Mar Pollut Bull ; 203: 116434, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38713928

RESUMO

Following a fuel leakage inside a Portuguese maritime port, we conducted parallel 30-day experiments using contaminated seawater and fuel, sampled five days after the incident. This study aimed to (i)survey the native microbial community response to the spilled fuel and (ii)evaluate the efficacy of bioremediation, both biostimulation and bioaugmentation with a lyophilized bacterial consortium (Rhodococcus erythropolis, Pseudomonas sp.), in accelerating hydrocarbon degradation. Metabarcoding analysis revealed a shift in microbial communities, with increased abundance of hydrocarbon-degraders (e.g. Alcanivorax, Thalassospira). Ninety-five hydrocarbonoclastic bacteria were isolated, including key groups from the enriched communities. The lyophilized bacteria added in bioaugmentation, enhanced the abundance of hydrocarbon-degraders over time and were recovered throughout time. Bioremediation treatments favoured biodegradation, achieving over 60 % removal of total petroleum hydrocarbons after 15 days, contrasting with natural attenuation where almost no TPH was removed. This work highlights the potential of bioremediation technologies to accelerate hydrocarbon-degrading activity, for oil spills inside ports.


Assuntos
Biodegradação Ambiental , Hidrocarbonetos , Poluição por Petróleo , Água do Mar , Poluentes Químicos da Água , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/análise , Água do Mar/microbiologia , Hidrocarbonetos/metabolismo , Bactérias/metabolismo , Petróleo/metabolismo , Portugal , Microbiota
14.
Front Pharmacol ; 15: 1347485, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38576493

RESUMO

Bioprospecting actinobacterial secondary metabolism from untapped marine sources may lead to the discovery of biotechnologically-relevant compounds. While studying the diversity and bioactive potential of Actinomycetota associated with Codium tomentosum, a green seaweed collected in the northern Portuguese cost, strain CT-F61, identified as Streptomyces violaceoruber, was isolated. Its extracts displayed a strong anticancer activity on breast carcinoma T-47D and colorectal carcinoma HCT116 cells, being effective as well against a panel of human and fish pathogenic bacteria. Following a bioactivity-guided isolation pipeline, a new analogue of the red-pigmented family of the antibiotics prodigiosins, decylprodigiosin (1), was identified and chemically characterized. Despite this family of natural products being well-known for a long time, we report a new analogue and the first evidence for prodigiosins being produced by a seaweed-associated actinomycete.

15.
Biodegradation ; 24(2): 245-55, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22842857

RESUMO

Organic and metallic pollutants are ubiquitous in the environment. Many metals are reported to be toxic to microorganisms and to inhibit biodegradation. The effect of the metals iron, copper and silver on the metabolism of Labrys portucalensis F11 and on fluorobenzene (FB) biodegradation was examined. The results indicate that the addition of 1 mM of Fe(2+) to the culture medium has a positive effect on bacterial growth and has no impact in the biodegradation of 1 and 2 mM of FB. The presence of 1 mM of Cu(2+) was found to strongly inhibit the growth of F11 cultures and to reduce the biodegradation of 1 and 2 mM of FB to ca. 50 %, with 80 % of stoichiometrically expected fluoride released. In the experiments with resting cells, the FB degraded (from 2 mM supplied) was reduced ca. 20 % whereas the fluoride released was reduced to 45 % of that stoichiometrically expected. Ag(+) was the most potent inhibitor of FB degradation. In experiments with growing cells, the addition of 1 mM of Ag(+) to the culture medium containing 1 and 2 mM of FB resulted in no fluoride release, whereas FB degradation was only one third of that observed in control cultures. In the experiments with resting cells, the addition of Ag(+) resulted in 25 % reduction in substrate degradation and fluoride release was only 20 % of that stoichiometrically expected. The accumulation of catechol and 4-fluorocatechol in cultures supplemented with Cu(2+) or Ag(+) suggest inhibition of the key enzyme of FB metabolism-catechol 1,2-dioxygenase.


Assuntos
Alphaproteobacteria/metabolismo , Biodegradação Ambiental/efeitos dos fármacos , Catecóis/metabolismo , Cobre/farmacologia , Ferro/farmacologia , Prata/farmacologia , Alphaproteobacteria/efeitos dos fármacos
16.
Mar Pollut Bull ; 194(Pt A): 115309, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37591052

RESUMO

Per- and polyfluorinated alkyl substances (PFAS) have long been known for their detrimental effects on the ecosystems and living organisms; however the long-term impact on the marine environment is still insufficiently recognized. Based on PFAS persistence and bioaccumulation in the complex marine food network, adverse effects will be exacerbated by global processes such as climate change and synergies with other pollutants, like microplastics. The range of fluorochemicals currently included in the PFAS umbrella has significantly expanded due to the updated OECD definition, raising new concerns about their poorly understood dynamics and negative effects on the ocean wildlife and human health. Mitigation challenges and approaches, including biodegradation and currently studied materials for PFAS environmental removal are proposed here, highlighting the importance of ongoing monitoring and bridging research gaps. The PFAS EU regulations, good practices and legal frameworks are discussed, with emphasis on recommendations for improving marine ecosystem management.


Assuntos
Fluorocarbonos , Saúde Única , Humanos , Animais , Ecossistema , Plásticos , Animais Selvagens
17.
Front Microbiol ; 14: 1158441, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37065153

RESUMO

The deep-sea covers over 70% of the Earth's surface and harbors predominantly uncharacterized bacterial communities. Actinobacteria are the major prokaryotic source of bioactive natural products that find their way into drug discovery programs, and the deep-sea is a promising source of biotechnologically relevant actinobacteria. Previous studies on actinobacteria in deep-sea sediments were either regionally restricted or did not combine a community characterization with the analysis of their bioactive potential. Here we characterized the actinobacterial communities of upper layers of deep-sea sediments from the Arctic and the Atlantic (Azores and Madeira) ocean basins, employing 16S rRNA metabarcoding, and studied the biosynthetic potential of cultivable actinobacteria retrieved from those samples. Metabarcoding analysis showed that the actinobacterial composition varied between the sampled regions, with higher abundance in the Arctic samples but higher diversity in the Atlantic ones. Twenty actinobacterial genera were detected using metabarcoding, as a culture-independent method, while culture-dependent methods only allowed the identification of nine genera. Isolation of actinobacteria resulted on the retrieval of 44 isolates, mainly associated with Brachybacterium, Microbacterium, and Brevibacterium genera. Some of these isolates were only identified on a specific sampled region. Chemical extracts of the actinobacterial isolates were subsequently screened for their antimicrobial, anticancer and anti-inflammatory activities. Extracts from two Streptomyces strains demonstrated activity against Candida albicans. Additionally, eight extracts (obtained from Brachybacterium, Brevibacterium, Microbacterium, Rhodococcus, and Streptomyces isolates) showed significant activity against at least one of the tested cancer cell lines (HepG2 and T-47D). Furthermore, 15 actinobacterial extracts showed anti-inflammatory potential in the RAW 264.4 cell model assay, with no concomitant cytotoxic response. Dereplication and molecular networking analysis of the bioactive actinobacterial extracts showed the presence of some metabolites associated with known natural products, but one of the analyzed clusters did not show any match with the natural products described as responsible for these bioactivities. Overall, we were able to recover taxonomically diverse actinobacteria with different bioactivities from the studied deep-sea samples. The conjugation of culture-dependent and -independent methods allows a better understanding of the actinobacterial diversity of deep-sea environments, which is important for the optimization of approaches to obtain novel chemically-rich isolates.

19.
Animals (Basel) ; 13(6)2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36978609

RESUMO

A fish trial was carried out to evaluate the combined effects of temperature and dietary lipid level on the body composition, growth performance, and freshness profile of the European seabass (Dicentrarchus labrax). Fish were kept for 56 days at 20 °C and 24 °C and fed on two diets, with 16% and 20% lipid. At the end of the trial, fish were euthanized at two temperature conditions (0.6 °C or -0.6 °C) and kept on ice for 10 days at 4 °C to evaluate their freshness condition. Findings demonstrated that fish reared at 24 °C presented a lower lipid level and a higher daily growth index than those at 20 °C. Additionally, sensory analysis (Quality Index Method-QIM) and microbiological analysis revealed that fish reared at 24 °C showed better freshness conditions than those at 20 °C. However, the 16S rRNA metabarcoding analyses revealed a higher proliferation of genera associated with fish-spoiling bacteria in the skin microbiome of fish reared at 24 °C, i.e., Vibrio and Acinetobacter, which was not observed in the skin microbiome of fish reared at 20 °C. Nevertheless, the dietary lipid level did not have any influence on fish freshness. Therefore, our data suggest that the increase in temperature to 24 °C is beneficial for the growth and freshness profile (lower QIM and lower CFUs/cm2) of this particular species. Additionally, the lower euthanasia temperature (-0.6 °C) seems to lead to higher fish freshness than the normal temperature (0.6 °C).

20.
Clin Transplant ; 26(2): 345-50, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22017269

RESUMO

The purpose of this article was to report a series of 23 renal transplant recipients with histologically proven and immunohistochemically confirmed cytomegalovirus (CMV) lesions in the gastrointestinal tract (GIT) and to assess the risk factors associated with severe disease/mortality. CMV patients (n=23) were allocated into two groups: those who died (n=6) and those considered cured (n=17). Overall mortality rate was 26% (6/23). Initial symptoms suggestive of lower GIT involvement were observed in all death cases and in 35.3% of those cured (p=0.01). Enterorrhagia was seen in 83.3% of the patients who died. Death risk increased twofold (RR 2 [1.13-3.52], p=0.01) when symptoms of lower GIT involvement were initially observed and sixfold when enterrohagia was present (RR 6 [1.1-35.9], p=0.001). Among death cases, mean time at diagnosis was significantly more distant (2002±2.9×2008±1.6, p=0.04). The difference in mortality rates seen as service practices changed along the years demonstrates the importance of early diagnosis.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Gastroenteropatias/diagnóstico , Transplante de Rim , Infecções Oportunistas/diagnóstico , Adulto , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/mortalidade , Feminino , Gastroenteropatias/tratamento farmacológico , Gastroenteropatias/mortalidade , Gastroenteropatias/virologia , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/tratamento farmacológico , Fatores de Risco
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