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1.
Prog Chem Org Nat Prod ; 111: 81-153, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32114663

RESUMO

Marine-derived fungi play an important role in the search for structurally unique secondary metabolites, some of which show promising pharmacological activities that make them useful leads for drug discovery. Marine natural product research in China in general has made enormous progress in the last two decades as described in this chapter on fungal metabolites. This contribution covers 613 new natural products reported from 2001 to 2017 from marine-derived fungi obtained from algae, sponges, corals, and other marine organisms from Chinese waters. The genera Aspergillus (170 new natural products, 28%) and Penicillium (70 new natural products, 11%) were the main fungal producers of new natural products during the time period covered, whereas sponges (184 new natural products, 30%) were the most abundant source of new natural products, followed by corals (154 new natural products, 25%) and algae (130 new natural products, 21%). Close to 40% of all natural products covered in this contribution displayed various bioactivities. The major bioactivities reported were cytotoxicity against different cancer cell lines, antimicrobial (mainly antibacterial) activity, and antiviral activity, which accounted for 13%, 9%, and 3% of all natural products reported. In terms of structural classes, polyketides (188 new natural products, 31%) play a dominant role, and if prenylated polyketides and nitrogen-containing polyketides (included in meroterpenes and alkaloids in this contribution) are taken into account, their total number even exceeds 50%. Nitrogen-containing compounds including peptides (65 new natural products, 10%) and alkaloids (103 new natural products, 17%) are the second largest group.


Assuntos
Produtos Biológicos/farmacologia , Fungos/química , Policetídeos/farmacologia , Animais , Antozoários/microbiologia , Anti-Infecciosos , Antineoplásicos , Organismos Aquáticos/microbiologia , Aspergillus/química , Produtos Biológicos/química , China , Penicillium/química , Policetídeos/química , Poríferos/microbiologia , Metabolismo Secundário
2.
PLoS One ; 15(1): e0227864, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31990915

RESUMO

The type VI secretion system (T6SS) is a nanomachine capable of killing adjacent microbial cells in a contact-dependent manner. Due to limited studies, relatively little is known about the range of marine bacteria that are susceptible to T6SS attack. Here, 15 diverse marine bacterial isolates from the phyla Bacteroidetes and Ɣ-Proteobacteria were challenged against the marine bacterium and human pathogen, Vibrio cholerae, which has a well described T6SS. V. cholerae killed several of the tested Ɣ-Proteobacteria, including members of the orders Vibrionales, Alteromonadales, Oceanospirillales, and Pseudomonadales. In contrast, V. cholerae co-existed with multiple Bacteroidetes and Ɣ-Proteobacteria isolates, but was killed by Vibrio coralliilyticus. Follow-up experiments revealed that five V. coralliilyticus strains, including known coral and shellfish pathogens survived the T6SS challenge and killed V. cholerae. By using predicted protein comparisons and mutagenesis, we conclude that V. coralliilyticus protected itself in the challenge by using its own T6SS to kill V. cholerae. This study provides valuable insight into the resilience and susceptibility of marine bacteria to the V. cholerae T6SS, and provides the first evidence for a functional T6SS in V. coralliilyticus, both of which have implications for human and ocean health.


Assuntos
Sistemas de Secreção Tipo VI/genética , Vibrio cholerae/patogenicidade , Vibrio/genética , Animais , Antozoários/microbiologia , Anticorpos Antibacterianos/genética , Proteínas de Bactérias/genética , Bacteroidetes/genética , Regulação Bacteriana da Expressão Gênica/genética , Proteobactérias/genética , Frutos do Mar/microbiologia , Vibrio cholerae/genética
3.
PLoS Biol ; 17(9): e3000483, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31545807

RESUMO

Coral reefs are the most diverse habitats in the marine realm. Their productivity, structural complexity, and biodiversity critically depend on ecosystem services provided by corals that are threatened because of climate change effects-in particular, ocean warming and acidification. The coral holobiont is composed of the coral animal host, endosymbiotic dinoflagellates, associated viruses, bacteria, and other microeukaryotes. In particular, the mandatory photosymbiosis with microalgae of the family Symbiodiniaceae and its consequences on the evolution, physiology, and stress resilience of the coral holobiont have yet to be fully elucidated. The functioning of the holobiont as a whole is largely unknown, although bacteria and viruses are presumed to play roles in metabolic interactions, immunity, and stress tolerance. In the context of climate change and anthropogenic threats on coral reef ecosystems, the Tara Pacific project aims to provide a baseline of the "-omics" complexity of the coral holobiont and its ecosystem across the Pacific Ocean and for various oceanographically distinct defined areas. Inspired by the previous Tara Oceans expeditions, the Tara Pacific expedition (2016-2018) has applied a pan-ecosystemic approach on coral reefs throughout the Pacific Ocean, drawing an east-west transect from Panama to Papua New Guinea and a south-north transect from Australia to Japan, sampling corals throughout 32 island systems with local replicates. Tara Pacific has developed and applied state-of-the-art technologies in very-high-throughput genetic sequencing and molecular analysis to reveal the entire microbial and chemical diversity as well as functional traits associated with coral holobionts, together with various measures on environmental forcing. This ambitious project aims at revealing a massive amount of novel biodiversity, shedding light on the complex links between genomes, transcriptomes, metabolomes, organisms, and ecosystem functions in coral reefs and providing a reference of the biological state of modern coral reefs in the Anthropocene.


Assuntos
Antozoários/microbiologia , Recifes de Corais , Expedições , Microbiota , Animais , Metabolômica , Metagenômica , Oceano Pacífico , Simbiose
4.
Mar Drugs ; 17(8)2019 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-31405226

RESUMO

Marine invertebrates and their associated microorganisms are rich sources of bioactive compounds. Among them, coral and its associated microorganisms are promising providers of marine bioactive compounds. The present review provides an overview of bioactive compounds that are produced by corals and coral-associated microorganisms, covering the literature from 2010 to March 2019. Accordingly, 245 natural products that possess a wide range of potent bioactivities, such as anti-inflammatory, cytotoxic, antimicrobial, antivirus, and antifouling activities, among others, are described in this review.


Assuntos
Antozoários/química , Antozoários/microbiologia , Organismos Aquáticos/química , Fatores Biológicos/química , Fatores Biológicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Animais , Humanos
5.
Nat Commun ; 10(1): 3092, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300639

RESUMO

The global decline of coral reefs heightens the need to understand how corals respond to changing environmental conditions. Corals are metaorganisms, so-called holobionts, and restructuring of the associated bacterial community has been suggested as a means of holobiont adaptation. However, the potential for restructuring of bacterial communities across coral species in different environments has not been systematically investigated. Here we show that bacterial community structure responds in a coral host-specific manner upon cross-transplantation between reef sites with differing levels of anthropogenic impact. The coral Acropora hemprichii harbors a highly flexible microbiome that differs between each level of anthropogenic impact to which the corals had been transplanted. In contrast, the microbiome of the coral Pocillopora verrucosa remains remarkably stable. Interestingly, upon cross-transplantation to unaffected sites, we find that microbiomes become indistinguishable from back-transplanted controls, suggesting the ability of microbiomes to recover. It remains unclear whether differences to associate with bacteria flexibly reflects different holobiont adaptation mechanisms to respond to environmental change.


Assuntos
Aclimatação/fisiologia , Antozoários/microbiologia , Antozoários/fisiologia , Translocação Bacteriana/fisiologia , Interações entre Hospedeiro e Microrganismos/fisiologia , Microbiota/fisiologia , Animais , Recifes de Corais , Simbiose
6.
Pak J Pharm Sci ; 32(3): 969-972, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31278708

RESUMO

Marine environment continues to be a huge source of pharmacologically active compounds that cure deadly disease. This research investigates the bioactive efficacy of bacteria isolated from surface of the coral, Junceella juncea (Pallas, 1766). 128 bacterial strains were isolated from the coral Junceella juncea from Tuticorin coast, Gulf of Mannar region, south east coast of India. The strains were tested against selected five human pathogens. Initial screening shows that the strain SG3 was found to exhibit broad spectral activity inhibiting Staplylococcus aureus. Also, twenty other strains were found to be active against various pathogens. Based on 16S rRNA sequencing and phylogenetic identification, the stain SG3 was identified to fell under the genera Bacillus. The ethanol precipitated of the culture broth (SG3) was done and its activity was noted. Mass spectrophotometry (MALDI-TOF) analysis has shown that the mass of the molecules ranged from 1225 Da to 1927 Da. Thus the marine bacteria isolated from corals are a potential source of novel bioactive agents and other natural products. Epibiotic bacteria also direct future isolation of peptide anti-MRSA compounds from marine source.


Assuntos
Antozoários/microbiologia , Antibacterianos/farmacologia , Bacillus/isolamento & purificação , Filogenia , Animais , Bacillus/química , Bacillus/genética , Bacillus/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Índia , RNA Ribossômico 16S , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Staphylococcus aureus/efeitos dos fármacos
7.
Mar Drugs ; 17(7)2019 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-31284571

RESUMO

Ochrazepines A-D (1-4), four new conjugates dimerized from 2-hydroxycircumdatin C (5) and aspyrone (6) by a nucleophilic addition to epoxide, were isolated from the fermentation broth of the coral-associated Aspergillus ochraceus strain LCJ11-102. Their structures including absolute configurations were determined based on spectroscopic analysis and chemical methods. Compounds 1-4 were also obtained by the semisynthesis from a nucleophilic addition of 2-hydroxycircumdatin C (5) to aspyrone (6). New compound 1 exhibited cytotoxic activity against 10 human cancer cell lines while new compounds 2 and 4 selectively inhibited U251 (human glioblastoma cell line) and compound 3 was active against A673 (human rhabdomyoma cell line), U87 (human glioblastoma cell line), and Hep3B (human liver cancer cell line) with IC50 (half maximal inhibitory concentration) values of 2.5-11.3 µM among 26 tested human cancer cell lines.


Assuntos
Antozoários/microbiologia , Aspergillus ochraceus/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Fermentação/fisiologia , Humanos , Concentração Inibidora 50 , Pironas/química , Pironas/farmacologia
8.
Curr Med Chem ; 26(38): 6930-6941, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31241431

RESUMO

Coral-derived microorganisms are known for their inherent ability to produce novel products of pharmaceutical importance. Nearly 260 marine natural products (MNPs) have been isolated from coral-derived microorganisms till 2014. In the last three years, 118 MNPs have been isolated from coral-associated microorganisms including 46 new compounds, two with a novel skeleton, and four new natural products. Most of them exhibited in vitro or in vivo activities against tumor cell lines, parasites, pathogenic bacteria, fungi and virus. We reviewed the natural products reported from 2015 to 2017 that have a wide range of bioactivities against different biological targets.


Assuntos
Antozoários/microbiologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Água do Mar , Animais , Anti-Infecciosos/farmacologia , Bactérias/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Fungos/metabolismo , Humanos , Testes de Sensibilidade Microbiana
9.
Mar Drugs ; 17(6)2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31212714

RESUMO

Erythrobacter flavus strain KJ5 (formerly called Erythrobacter sp. strain KJ5) is a yellowish marine bacterium that was isolated from a hard coral Acropora nasuta in the Karimunjawa Islands, Indonesia. The complete genome sequence of the bacterium has been reported recently. In this study, we examined the carotenoid composition of this bacterium using high-performance liquid chromatography coupled with ESI-MS/MS. We found that the bacterium produced sulfur-containing carotenoids, i.e., caloxanthin sulfate and nostoxanthin sulfate, as the most abundant carotenoids. A new carotenoid zeaxanthin sulfate was detected based on its ESI-MS/MS spectrum. The unique presence of sulfated carotenoids found among the currently known species of the Erythrobacter genus were discussed.


Assuntos
Antozoários/microbiologia , Carotenoides/química , Sphingomonadaceae/química , Enxofre/química , Animais , DNA Bacteriano/genética , Indonésia , Xantofilas/química
10.
Environ Sci Pollut Res Int ; 26(17): 17845-17852, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31041713

RESUMO

Worldwide, reef building corals are being degraded due to increasing anthropogenic pressure, and as a result, macroalgal cover is being increased. Hence, mechanism of coral-algal interaction, differential coral response to algal overgrowth, is critical from every geographical location to predict future coral dynamics. This paper documents the frequency of coral-algal (Halimeda) interactions, differential coral response to algal interaction. We found difference in susceptibility among coral genera to competitive effects. Out of 970 coral colonies surveyed, 36.7% were in contact with Halimeda sp. Most frequent contact was observed in Porites (57%) followed by Favites 28% (n = 60), Acropora 26% (n = 48), Platygyra 5% (n = 5) and Symphyllia 4.2% (n = 3). Frequent discoloration and tissue loss were only observed in Porites. Continuous monitoring revealed that long-term algal physical contact prevents light required for polyp for photosynthesis and stops coral feeding ability. In this study, we also found mutual exclusion between Halimeda and coral recruit. Out of 180 coral colonies (size class between 5 and 15 cm) comprised of Favites (n = 74), Acropora (n = 20), Favia (n = 79) and Porites (n = 7) surveyed, none of them were found in Halimeda-dominated sites. The documented effects of recruitment exclusion and tissue mortality followed by algal interaction on major reef building corals (Porites) could affect replenishing process and health of the remaining healthy corals in the Palk Bay reef if algal proliferation rate is not controlled through proper management strategies.


Assuntos
Antozoários/fisiologia , Clorófitas/fisiologia , Recifes de Corais , Animais , Antozoários/microbiologia , Índia
11.
Environ Pollut ; 250: 792-806, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31042619

RESUMO

The potential impacts of mining activities on tropical coastal ecosystems are poorly understood. In particular, limited information is available on the effects of metals on scleractinian corals which are foundation species that form vital structural habitats supporting other biota. This study investigated the effects of dissolved nickel and copper on the coral Acropora muricata and its associated microbiota. Corals collected from the Great Barrier Reef were exposed to dissolved nickel (45, 90, 470, 900 and 9050 µg Ni/L) or copper (4, 11, 32 and 65 µg Cu/L) in flow through chambers at the National Sea Simulator, Townsville, Qld, Australia. After a 96-h exposure DNA metabarcoding (16S rDNA and 18S rDNA) was undertaken on all samples to detect changes in the structure of the coral microbiome. The controls remained healthy throughout the study period. After 36 h, bleaching was only observed in corals exposed to 32 and 65 µg Cu/L and very high nickel concentrations (9050 µg Ni/L). At 96 h, significant discolouration of corals was only observed in 470 and 900 µg Ni/L treatments, the highest concentrations tested. While high concentrations of nickel caused bleaching, no changes in the composition of their microbiome communities were observed. In contrast, exposure to copper not only resulted in bleaching, but altered the composition of both the eukaryote and bacterial communities of the coral's microbiomes. Our findings showed that these effects were only evident at relatively high concentrations of nickel and copper, reflecting concentrations observed only in extremely polluted environments. Elevated metal concentrations have the capacity to alter the microbiomes which are inherently linked to coral health.


Assuntos
Antozoários/efeitos dos fármacos , Cobre/toxicidade , Microbiota/efeitos dos fármacos , Níquel/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antozoários/microbiologia , Austrália , Recifes de Corais , Relação Dose-Resposta a Droga , Mineração , Modelos Teóricos , Solubilidade , Clima Tropical
12.
Mar Drugs ; 17(5)2019 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-31035506

RESUMO

Three new diketopiperazine alkaloids, including two oxepine-containing diketopiperazines, chrysopiperazines A and B (1 and 2), and one quinazoline-containing diketopiperazine, chrysopiperazine C (5), together with three known analogues (3, 4, and 6), were isolated from the gorgonian-derived Penicillium chrysogenum fungus. The relative and absolute configurations of C-3 and C-15 in 1 and 2, C-3 and C-14 in 5 were established by NOE modified Marfey's analysis and electronic circular dichroism (ECD) calculations. Particularly, the absolute configurations of C-19 in 1 and 3, which was very challenging to be identified due to the flexible conformation in a short aliphatic chain, were successfully determined by the vibrational circular dichroism (VCD) method, supplying with a reliable and optional method to define the absolute configurations. Additionally, this is the first report on oxepine-containing diketopiperazines from the genus Penicillium.


Assuntos
Alcaloides/química , Antozoários/microbiologia , Dicetopiperazinas/química , Penicillium chrysogenum/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Dicroísmo Circular , Dicetopiperazinas/isolamento & purificação , Dicetopiperazinas/farmacologia , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Conformação Molecular , Estrutura Molecular , Espectroscopia de Prótons por Ressonância Magnética
13.
J Antibiot (Tokyo) ; 72(8): 634-639, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31118481

RESUMO

A new catecholate-containing siderophore, labrenzbactin (1), was isolated from the fermentation broth of a coral-associated bacterium Labrenzia sp. The structure and absolute configuration of 1 was determined by spectroscopic methods and Marfey's analysis. Overall, 1 showed antimicrobial activity against Ralstonia solanacearum SUPP1541 and Micrococcus luteus ATCC9341 with MIC values of 25 and 50 µg ml-1, respectively, and cytotoxicity against P388 murine leukemia cells with an IC50 of 13 µM.


Assuntos
Alphaproteobacteria/química , Antozoários/microbiologia , Antibacterianos/isolamento & purificação , Catecóis/isolamento & purificação , Oxazóis/isolamento & purificação , Sideróforos/isolamento & purificação , Alphaproteobacteria/isolamento & purificação , Animais , Antibacterianos/farmacologia , Antibióticos Antineoplásicos/isolamento & purificação , Antibióticos Antineoplásicos/farmacologia , Catecóis/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Fermentação , Leucemia P388/tratamento farmacológico , Camundongos , Testes de Sensibilidade Microbiana , Micrococcus luteus/efeitos dos fármacos , Estrutura Molecular , Oxazóis/farmacologia , Ralstonia/efeitos dos fármacos , Sideróforos/farmacologia
14.
Microb Pathog ; 132: 343-354, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31100406

RESUMO

In the present study, an attempt has been made to explore the antibiofilm activity of bioactive compound 1-hydroxy-1-norresistomycin (HNM) derived from coral mucus associated actinomycete Streptomyces variabilis. Initially, different concentration of HNM inhibited the biofilm formation of human clinical pathogens Escherichia coli, Vibrio cholerae and Staphylococcus aureus was determined using crystal-violet staining assay. The light microscopic analysis showed that HNM reduced the biofilm formation and adherence of bacterial cells on the surface of coverslip. HNM also damages the 3D architecture with reduced thickness as well as cell aggregation of biofilm forming bacteria analysed by confocal laser scanning microscopy (CLSM). In addition, HNM also demonstrated the efficiency in inhibiting theoretical adhesion by altering the surface hydrophobicity that can potentially hamper cellular adhesion and prevent biofilm formation. Furthermore, the molecular docking showed the significant interaction between HNM and key biofilm forming proteins proved an excellent antibiofilm activity of HNM. Together, these results suggest that the HNM can serve as potential antibiofilm agent in controlling the infections of E. coli, V. cholerae and S. aureus.


Assuntos
Biofilmes/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Pirenos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Vibrio cholerae/efeitos dos fármacos , Actinobacteria/metabolismo , Animais , Antozoários/microbiologia , Fator de Transcrição AraC/efeitos dos fármacos , Aderência Bacteriana/efeitos dos fármacos , Proteínas de Bactérias/efeitos dos fármacos , Simulação por Computador , Cisteína Endopeptidases/efeitos dos fármacos , Proteínas de Escherichia coli/efeitos dos fármacos , Humanos , Ligação de Hidrogênio , Simulação de Acoplamento Molecular , Pirenos/química , Streptomyces/metabolismo , Transativadores/efeitos dos fármacos , Peixe-Zebra
15.
Sci Total Environ ; 672: 855-861, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30978547

RESUMO

Symbiosis, mainly due to the advances in -omics technology and to the microbiome revolution, is being increasingly acknowledged as fundamental to explain any aspect of life existence. Previously considered an exception, a peculiar characteristic of few systems like lichens, corals and mycorrhizas, symbiosis is nowadays recognized as the rule, with the microbiome being part of all living entities and systems. However, our knowledge of the ecological meaning and functioning of many symbiotic systems is still limited. Here, we discuss a new, integrative approach based on current findings that looks at commonalities among symbiotic systems to produce theoretical models and conceptual knowledge that would allow a more efficient exploitation of symbiosis-based biotechnologies. The microbiome recruitment and assemblage processes are indicated as one of the potential targets where a holistic approach could bring advantages. Finally, we reflect on the potential socio-economic and environmental consequences of a symbiotic view of the world, where co-dependence is the matrix of life.


Assuntos
Microbiota , Simbiose , Animais , Antozoários/microbiologia
17.
FEMS Microbiol Lett ; 366(6)2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30939203

RESUMO

The enormous variability in richness, abundance and diversity of unknown bacterial organisms inhabiting the coral microbiome have challenged our understanding of their functional contribution to coral health. Identifying the attributes of the healthy meta-organism is paramount for contemporary approaches aiming to manipulate dysbiotic stages of the coral microbiome. This review evaluates the current knowledge on the structure and mechanisms driving bacterial communities in the coral microbiome and discusses two topics requiring further research to define the healthy coral microbiome. (i) We examine the necessity to establish microbial baselines to understand the spatial and temporal dynamics of the healthy coral microbiome and summarise conceptual and logistic challenges to consider in the design of these baselines. (ii) We propose potential mechanical, physical and chemical mechanisms driving bacterial distribution within coral compartments and suggest experiments to test them. Finally, we highlight aspects of the use of 16S amplicon sequencing requiring standardization and discuss its contribution to other multi-omics approaches.


Assuntos
Antozoários/microbiologia , Bactérias/classificação , Bactérias/isolamento & purificação , Microbiota , Animais , Antozoários/crescimento & desenvolvimento , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Filogenia
18.
Arch Microbiol ; 201(6): 757-767, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30840101

RESUMO

Bacteria in corals have been studied in detail in the past decades. However, the biodiversity and bioactivity of fungi in corals are still poorly understood. This study investigated the biodiversity and antifouling activity of fungi in soft corals Cladiella krempfi and Sarcophyton tortuosum from the South China Sea. A high diverse and abundant fungal community was found in the two soft corals. Furthermore, five isolates shared 83-95% similarity with their closest relatives, indicating that they might be novel species in genera Phaeoshaeria and Mucor. In addition, approximately 50% of the representative isolates exhibited distinct antifouling activity. In particular, isolates Fungal sp. SCAU132 and Fungal sp. SCAU133 displayed very strong antifouling activity against Bugula neritina, suggesting they can provide a potential resource for further investigation on isolation of novel antifouling metabolites. To our knowledge, this study is the first report to investigate the biodiversity and antifouling activity of fungi in C. krempfi and S. tortuosum.


Assuntos
Antozoários/microbiologia , Biodiversidade , Fungos/fisiologia , Animais , Antozoários/classificação , Incrustação Biológica , Briozoários/fisiologia , China , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Oceanos e Mares , Filogenia
19.
Dev Comp Immunol ; 96: 103-110, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30857983

RESUMO

Lectins serve as essential pattern recognition receptors, and play important roles in the recognition of non-self and mediation of innate immune response in metazoans. Scleractinian corals are vulnerable to pathogen infection and endosymbiosis disruption under heat stress that can finally lead to coral bleaching. In this study, a cDNA sequence encoding one galectin was cloned in scleractinian coral Pocillopora damicornis (PdGLT-1). The deduced PdGLT-1 protein shared highest amino acid sequence similarity (99%) with galectin from Stylophora pistillata (XP_022806650.1), and was composed of one signal peptide, one Collagen domain and one Gal-Lectin domain. PdGLT-1 recombinant protein (rPdGLT-1) was expressed and purified in vitro. Binding activities of rPdGLT-1 to bacteria and symbiont were determined using western blotting method. Results showed that rPdGLT-1 was able to bind to gram-positive bacterium Streptococcus mutans, gram-negative bacteria Vibrio coralliilyticus and Escherichia coli, with the highest activity for V. coralliilyticus, and further agglutinated them. The bound rPdGLT-1 to Symbiodinium (10-104 cells mL-1) was detectable, and its binding ability was concentration-dependent. Furthermore, dual binding activities were determined under different temperatures (20, 25, 30 and 35 °C), and the optimal temperatures were found to be 25 and 30 °C for V. coralliilyticus and Symbiodinium, respectively. Results suggested that PdGLT-1 could recognize pathogenic bacteria and symbiotic dinoflagellates Symbiodinium. However, their recognition activities were repressed under high temperature (>30 °C). This study provided insights into the underlying mechanism of lectin modulation to heat bleaching through its pathogen and Symbiodinium recognition in the scleractinian coral P. damicornis.


Assuntos
Antozoários/imunologia , Galectinas/imunologia , Interações entre Hospedeiro e Microrganismos/imunologia , Simbiose/imunologia , Temperatura , Sequência de Aminoácidos , Animais , Antozoários/microbiologia , Clonagem Molecular , Recifes de Corais , Escherichia coli/imunologia , Galectinas/genética , Galectinas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Streptococcus mutans/imunologia , Vibrio/imunologia
20.
PLoS One ; 14(3): e0213519, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30849101

RESUMO

Zooxanthellate corals live in symbiosis with phototrophic dinoflagellates of the family Symbiodiniaceae, enabling the host coral to dwell in shallow, nutrient-poor marine waters. The South Atlantic Ocean is characterized by low coral diversity with high levels of endemism. However, little is known about coral-dinoflagellate associations in the region. This study examined the diversity of Symbiodiniaceae associated with the scleractinian coral Favia gravida across its distributional range using the ITS-2 marker. This brooding coral endemic to the South Atlantic can be found across a wide range of latitudes and longitudes, including the Mid-Atlantic islands. Even though it occurs primarily in shallower environments, F. gravida is among the few coral species that live in habitats with extreme environmental conditions (high irradiance, temperature, and turbidity) such as very shallow tide pools. In the present study, we show that F. gravida exhibits some degree of flexibility in its symbiotic association with zooxanthellae across its range. F. gravida associates predominantly with Cladocopium C3 (ITS2 type Symbiodinium C3) but also with Symbiodinium A3, Symbiodinium linucheae (ITS2 type A4), Cladocopium C1, Cladocopium C130, and Fugacium F3. Symbiont diversity varied across biogeographic regions (Symbiodinium A3 and S. linucheae were found in the Tropical Eastern Atlantic, Cladocopium C1 in the Mid-Atlantic, and other subtypes in the Southwestern Atlantic) and was affected by local environmental conditions. In addition, Symbiodiniaceae diversity was highest in a southwestern Atlantic oceanic island (Rocas Atoll). Understanding the relationship between corals and their algal symbionts is critical in determining the factors that control the ecological niches of zooxanthellate corals and their symbionts, and identifying host-symbiont pairs that may be more resistant to environmental changes.


Assuntos
Antozoários , Recifes de Corais , Dinoflagelados/fisiologia , Modelos Biológicos , Simbiose/fisiologia , Animais , Antozoários/microbiologia , Antozoários/fisiologia , Filogeografia
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