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1.
Antonie Van Leeuwenhoek ; 116(4): 367-382, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36646940

ABSTRACT

Sponges are essential components of the marine benthos and well known for their complex and abundant associated microbial communities. There are five endemic species of the genus Halichondria on the Brazilian coast and H. cebimarensis is one of the least studied. This sponge has a very limited geographic distribution and is classified as vulnerable. In order to understand the bacterial and archaeal communities associated with this sponge, samples of H. cebimarensis were collected from the southwestern Atlantic coast (Brazil, São Paulo state). Choanosome samples were separated and processed to be (i) inoculated in three different culture media; (ii) investigated by transmission electron microscopy; (iii) submitted to 16S rRNA metabarcoding. Forty isolates were obtained and 12 were identified as belonging to the Bacilli class. The culture-dependent approaches allowed us to access unique members of the microbial community. Our analyses revealed that this animal belongs to the Low Microbial Abundance group of sponges. Culture-independent approaches showed that the H. cebimarensis microbiome is dominated by the heterotrophic Gammaproteobacteria AqS2 ("Ca. Amphirhobacter heronislandensis"). This is the first study to reveal details of the microbiome of this vulnerable sponge and is an important step in understanding how this sponge functions, its biotechnological potential and a contribution to conservation efforts.


Subject(s)
Archaea , Porifera , Animals , RNA, Ribosomal, 16S/genetics , Phylogeny , Brazil , Bacteria
2.
Microbiol Res ; 265: 127210, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36183422

ABSTRACT

While bacterial and archaeal communities of sponges are intensively studied, given their importance to the animal's physiology as well as sources of several new bioactive molecules, the potential and roles of associated protists remain poorly known. Historically, culture-dependent approaches dominated the investigations of sponge-protist interactions. With the advances in omics techniques, these associations could be visualized at other equally important scales. Of the few existing studies, there is a strong tendency to focus on interactions with photosynthesizing taxa such as dinoflagellates and diatoms, with fewer works dissecting the interactions with other less common groups. In addition, there are bottlenecks and inherent biases in using primer pairs and bioinformatics approaches in the most commonly used metabarcoding studies. Thus, this review addresses the issues underlying this association, using the term "microeukaryome" to refer exclusively to protists associated with an animal host. We aim to highlight the diversity and community composition of protists associated with sponges and place them on the same level as other microorganisms already well studied in this context. Among other shortcomings, it could be observed that the biotechnological potential of the microeukaryome is still largely unexplored, possibly being a valuable source of new pharmacological compounds, enzymes and metabolic processes.


Subject(s)
Dinoflagellida , Porifera , Animals , Archaea/genetics , Bacteria , Biotechnology , Dinoflagellida/genetics , Phylogeny
3.
Article in English | MEDLINE | ID: mdl-33359143

ABSTRACT

Wounds in living organisms trigger tissue-repair mechanisms. The sea cucumber (Holoturia tubulosa) is an excellent model species for achieving a better understanding of the humoral and cellular aspects involved in such healing processes. Consequently, this study assesses data on its morphometric, physiological and humoral responses 1, 2, 6, 24 and 48h after wound induction. In particular, morphometric data on the weight, width, length and coelomic-fluid volume of the species were estimated at different times during our experiments. In addition, the humoral aspects related to the enzymatic activity of esterase, alkaline phosphatase and peroxidase, as well as the cytotoxic activity of cell lysates (CL) and cell-free coelomic fluids (CfCf) are evaluated for the first time. Our results reveal a significant decrease in body length and weight, along with time-dependent, significant changes in the esterase, alkaline phosphatase, peroxidase and cytotoxic activity in both the CL and CfCf. The data obtained lead to the pioneering finding that there is an important time-dependent involvement of morphometric (changes in weight and length) and humoral (enzymatic and cytotoxic) responses in wound healing.


Subject(s)
Holothuria/physiology , Wound Healing , Animals , Body Weight , Holothuria/anatomy & histology , Holothuria/enzymology , Rabbits , Sheep
4.
Aquat Toxicol ; 227: 105609, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32906060

ABSTRACT

Species responses to stress are expected to be dependent on their life-history strategy. In this study, we compare the responses of two free-living marine nematodes, Litoditis marina and Diplolaimella dievengatensis, both considered opportunistic, fast-growing, and stress-tolerant species, to the exposure to sublethal concentrations of sodium dodecyl sulfate (SDS) surfactant. Specifically, we evaluated the growth and reproduction rates, as well as the survival of individuals exposed from eggs and/or juveniles (J1) onwards. Exposure to SDS significantly affected the growth and reproduction rates of both species. However, whereas growth and reproduction rates of D. dievengatensis were significantly enhanced at low and intermediate concentrations of SDS (0.001% and 0.003%), for L. marina both parameters were significantly reduced by all SDS concentrations tested (0.001%, 0.003% and 0.006%). Exposure to SDS did not affect the survival of adult nematodes of D. dievengatensis, while for L. marina, survival of males exposed to 0.006% SDS was significantly reduced compared to the control. Responses of the life-history traits growth, fecundity and survival did not exhibit clear trade-offs. The contrasting responses of D. dievengatensis and L. marina indicate that biologically and ecologically similar species can have remarkably distinct tolerances to stress, and that, in agreement with recent studies, rhabditid nematodes cannot a priori be considered very stress tolerant. Consequently, single species traits and phylogenetic relatedness are poor predictors of nematode responses to toxic stress posed by anthropogenic activities.


Subject(s)
Nematoda/physiology , Sodium Dodecyl Sulfate/toxicity , Surface-Active Agents/toxicity , Water Pollutants, Chemical/toxicity , Animals , Fertility , Male , Phylogeny
5.
Braz. arch. biol. technol ; 63: e20190084, 2020. graf
Article in English | LILACS | ID: biblio-1132177

ABSTRACT

Abstract Research on biomaterials of natural origin has gained prominence in the literature. Above all, marine sponges, due to their architecture and structural components, present a promising potential for the engineering of bone tissue. In vitro studies demonstrate that a biosilica of marine sponges has osteogenic potential. However, in vivo works are needed to elucidate the interaction of biosilica (BS) and bone tissue. The objective of the study was to evaluate the morphological and chemical characteristics of BS compared to Bioglass (BG) by scanning electron microscopy (SEM) and X-ray dispersive energy (EDX) spectroscopy. In addition, to evaluate the biological effects of BS, through an experimental model of tibial bone defect using histopathological, histomorphometric, immunohistochemical (IHC) and mechanical tests. SEM and EDX demonstrated the successful extraction of BS. Histopathological analysis demonstrated that Control Group (GC) had greater formation of newly formed bone tissue compared to BG and BS, yet BG bone neoformation was greater than BS. However, BS showed material degradation and granulation tissue formation, with absence of inflammatory process and formation of fibrotic capsule. The results of histomorphometry corroborate with those of histopathology, where it is worth emphasizing the positive influence of BS in osteoblastic activity. IHQ demonstrated positive VEGF and TGF-β immunoexpression for GC, BS and BG. In the mechanical test no significant differences were found. The present results demonstrate the potential of BS in bone repair, further studies are needed other forms of presentation of BS are needed.


Subject(s)
Animals , Male , Rats , Porifera , Tibial Fractures/therapy , Biocompatible Materials , Bone Regeneration , Osteogenesis , Tibial Fractures/pathology , In Vitro Techniques , Microscopy, Electron, Scanning , Ceramics/therapeutic use , Rats, Wistar , Disease Models, Animal
6.
J Hazard Mater ; 368: 63-71, 2019 04 15.
Article in English | MEDLINE | ID: mdl-30665109

ABSTRACT

Supramolecular structures were produced by auto-assembling CuCN blocks derived from copper-lipopeptides (CuLps) isolated from bioleaching liquor. Lipopeptides produced by B. subtilis Hyhel1 have been previously related as responsible by bioleaching and intracellular copper crystal production. However, there were no records relating CuLps to extracellular copper crystal production. To study this process, CuLps were isolated from bioleaching liquor and kept at 8 °C to facilitate the CuLps aggregation. After three months, blue spheres (BS) were observed in the CuLp fraction. These spheres were then analyzed by SEM-EDS, MALDI-TOF-MS/MS, GC-MS and FTIR. SEM-EDS analysis showed that they were formed by polycrystalline structures mainly composed by Cu (46.5% m/m) and positioned concentrically. MALDI-TOF-MS/MS and GCMS showed that peptide bonds of CuLp were broken, producing lipid chains and amino acids free. The FTIR of BS showed three nitro groups: CN, NN and NO, which were not found in the control. These data suggest that the CuLp amino acid produced a CN group linked to copper, as CuCN blocks, that auto-assembled in supramolecular structures. This phenomenon could be explored as a method to recover copper and to obtain supramolecular CuCN structures, which in turn may be used as template for superconductor or computing devices.


Subject(s)
Copper/chemistry , Cyanides/chemistry , Lipopeptides/chemistry , Electronic Waste
7.
J Biomed Mater Res B Appl Biomater ; 105(6): 1717-1727, 2017 08.
Article in English | MEDLINE | ID: mdl-27163295

ABSTRACT

Marine life and its rich biodiversity provide a plentiful resource of potential new products for the society. Remarkably, marine organisms still remain a largely unexploited resource for biotechnology applications. Among them, marine sponges are sessile animals from the phylum Porifera dated at least from 580 million years ago. It is known that molecules from marine sponges present a huge therapeutic potential in a wide range of applications mainly due to its antitumor, antiviral, anti-inflammatory, and antibiotic effects. In this context, this article reviews all the information available in the literature about the potential of the use of marine sponges for bone tissue engineering applications. First, one of the properties that make sponges interesting as bone substitutes is their structural characteristics. Most species have an efficient interconnected porous architecture, which allows them to process a significant amount of water and facilitates the flow of fluids, mimicking an ideal bone scaffold. Second, sponges have an organic component, the spongin, which is analogous to vertebral collagen, the most widely used natural polymer for tissue regeneration. Last, osteogenic properties of marine sponges is also highlighted by their mineral content, such as biosilica and other compounds, that are able to support cell growth and to stimulate bone formation and mineralization. This review focuses on recent studies concerning these interesting properties, as well as on some challenges to be overcome in the bone tissue engineering field. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1717-1727, 2017.


Subject(s)
Biomimetic Materials/chemistry , Bone and Bones , Porifera/chemistry , Tissue Engineering/methods , Tissue Scaffolds/chemistry , Animals , Biomimetic Materials/therapeutic use , Humans
8.
J Exp Zool A Ecol Genet Physiol ; 325(5): 294-303, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27194182

ABSTRACT

Sessile marine invertebrates living on hard substrata usually present strategies such as size variations, longer life spans, fragmentation and fusion to occupy and compete for space. Calcareous sponges are usually small and short-lived, and some species are known to undergo frequent fragmentation and fusion events. However, whether fusion occurs only between genetically identical individuals remains unclear. We investigated the occurrence of chimaeras in the calcareous sponge Clathrina aurea by following the dynamics of fragmentation and fusion of 66 individuals in the field for up to 18 months and determined size variations and the life span of each individual. Microsatellites were used to determine whether fusion events occur among genetically different individuals. Growth and shrinkage of individuals were frequently observed, showing that size cannot be associated with age in C. aurea. The life span of the species ranged from 1 to 16 months (mean: 4.7 months). Short life spans and variable growth rates have been observed in other species of the class Calcarea. Fragmentation and fusion events were observed, but fusion events always occurred between genetically identical individuals, as has been suggested by graft experiments in adult Demospongiae and other Calcarea. These results suggest that at least C. aurea adults may have some mechanism to avoid chimaerism.


Subject(s)
Genetic Variation , Porifera/physiology , Animals , Brazil , Genotype , Islands , Porifera/genetics
9.
Biota neotrop. (Online, Ed. port.) ; 11(4): 427-444, Oct.-Dec. 2011. ilus, tab
Article in Portuguese | LILACS-Express | LILACS | ID: lil-651622

ABSTRACT

As esponjas (Filo Porifera) são um dos metazoários mais antigos existentes, mas ainda facilmente encontradas em uma grande variedade de ambientes aquáticos. São um componente fundamental em diversos ecossistemas, influenciando diretamente a qualidade da água em seus habitats. Em tempos recentes são um dos grupos que mais fornece novas moléculas bioativas ou com estruturas incomuns. No entanto, são historicamente considerados um grupo de taxonomia complexa e ainda são comuns discussões acerca da sistemática ao nível de ordens ou mesmo da monofilia do grupo. Este cenário começou a ser alterado de forma marcante na última década, a partir de iniciativas multinacionais voltadas a fornecer uma base taxonômica mais sólida. No Brasil, este processo foi acompanhado pela publicação de guias de identificação para as esponjas do nosso litoral. Partindo dos dados esporádicos disponíveis em períodos anteriores, diversas iniciativas foram feitas especificamente voltadas para o levantamento das espécies de Porifera, principalmente nas regiões costeiras. Tais ações fornecem atualmente aos pesquisadores iniciantes uma base de conhecimento bem mais abrangente do que a disponível na década anterior. Nos dez anos passados desde as últimas listagens feitas para o Estado de São Paulo, houve uma alteração significativa no quadro apresentado. Conforme pôde ser verificado neste trabalho, o período foi sem sombra de dúvida o mais prolífico no que se refere ao conhecimento da espongiofauna local.


The sponges (Porifera) are one of the oldest extant metazoans, but still easily found in a wide variety of aquatic environments. They are key components in several ecosystems, directly influencing the quality of water in their habitat. In recent times, these organisms have become one of the most productive groups in providing new compounds with bioactivity or unusual structures. However, sponges are historically considered a group of complex taxonomy, and systematic discussions at order level or even about the monophyly of the group are still common. This situation began to change markedly in the last decade, with multinational initiatives aimed at providing a more solid taxonomic basis. In Brazil, this process was accompanied by the publication of identification guides of the native species. Starting from the sporadic data available in earlier periods, several initiatives were specifically targeted at the survey of Porifera species, particularly in coastal regions. Such actions now provide the researchers with a knowledge base far more comprehensive than that available a decade earlier. In the ten years since the last checklists for the São Paulo State were published, there was a significant change in the scenario. As verified by this study, the period was undoubtedly the most prolific regarding the knowledge of the local spongiofauna.

10.
Calcif Tissue Int ; 81(5): 382-93, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17957327

ABSTRACT

In a previous study (Schröder et al., J Biomed Mater Res B Appl Biomater 75:387-392, 2005) we demonstrated that human SaOS-2 cells, when cultivated on bio-silica matrices, respond with an increased hydroxyapatite deposition. In the present contribution we investigate if silica-based components (Na-silicate, tetraethyl orthosilicate [TEOS], silica-nanoparticles) (1) change the extent of biomineralization in vitro (SaOS-2 cells) and (2) cause an alteration of the expression of the genes amelogenin, ameloblastin, and enamelin, which are characteristic for an early stage of osteogenesis. We demonstrate that the viability of SaOS-2 cells was not affected by the silica-based components. If Na-silicate or TEOS was added together with ss-glycerophosphate, an organic phosphate donor, a significant increase in biomineralization was measured. Finally, expression levels of the amelogenin, ameloblastin, and enamelin genes were determined in SaOS-2 cells during exposure to the silica-based components. After exposure for 2 days, expression levels of amelogenin and enamelin strongly increased in response to the silica-based components, while no significant change was seen for ameloblastin. In contrast, exposure of SaOS-2 cells to ss-glycerophosphate resulted in increased expression of all three genes. We conclude that the levels of the structural molecules of the enamel matrix, amelogenin and enamelin, increase in the presence of silica-based components and substantially contribute to the extent of hydroxyapatite crystallite formation. These results demonstrate that silica-based components augment hydroxyapatite deposition in vitro and suggest that enzymatically synthesized bio-silica (via silicatein) might be a promising route for tooth reconstruction in vivo.


Subject(s)
Biocompatible Materials/pharmacology , Calcification, Physiologic/drug effects , Dental Enamel Proteins/genetics , Dental Enamel/growth & development , Gene Expression Regulation, Developmental/drug effects , Silicon Dioxide/pharmacology , Tooth/growth & development , Amelogenin/genetics , Biocompatible Materials/therapeutic use , Bone Regeneration/drug effects , Bone Regeneration/physiology , Calcification, Physiologic/physiology , Cell Line, Tumor , Dental Enamel/metabolism , Gene Expression Regulation, Developmental/genetics , Glycerophosphates/pharmacology , Humans , Microscopy, Electron, Scanning , RNA, Messenger/drug effects , RNA, Messenger/metabolism , Silicates/pharmacology , Silicates/therapeutic use , Silicon Dioxide/therapeutic use , Tooth/metabolism , Up-Regulation/drug effects , Up-Regulation/genetics
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