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1.
Adv Sci (Weinh) ; 9(11): e2105059, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35156333

RESUMO

Actin is a fundamental member of an ancient superfamily of structural intracellular proteins and plays a crucial role in cytoskeleton dynamics, ciliogenesis, phagocytosis, and force generation in both prokaryotes and eukaryotes. It is shown that actin has another function in metazoans: patterning biosilica deposition, a role that has spanned over 500 million years. Species of glass sponges (Hexactinellida) and demosponges (Demospongiae), representatives of the first metazoans, with a broad diversity of skeletal structures with hierarchical architecture unchanged since the late Precambrian, are studied. By etching their skeletons, organic templates dominated by individual F-actin filaments, including branched fibers and the longest, thickest actin fiber bundles ever reported, are isolated. It is proposed that these actin-rich filaments are not the primary site of biosilicification, but this highly sophisticated and multi-scale form of biomineralization in metazoans is ptterned.


Assuntos
Actinas , Dióxido de Silício , Vidro , Dióxido de Silício/química , Esqueleto
2.
Mater Sci Eng C Mater Biol Appl ; 109: 110566, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32228987

RESUMO

Marine demosponges of the Verongiida order are considered a gold-mine for bioinspired materials science and marine pharmacology. The aim of this work was to simultaneously isolate selected bromotyrosines and unique chitinous structures from A. aerophoba and to propose these molecules and biomaterials for possible application as antibacterial and antitumor compounds and as ready-to-use scaffolds for cultivation of cardiomyocytes, respectively. Among the extracted bromotyrosines, the attention has been focused on aeroplysinin-1 that showed interesting unexpected growth inhibition properties for some Gram-negative clinical multi-resistant bacterial strains, such as A. baumannii and K. pneumoniae, and on aeroplysinin-1 and on isofistularin-3 for their anti-tumorigenic activity. For both compounds, the effects are cell line dependent, with significant growth inhibition activity on the neuroblastoma cell line SH-SY5Y by aeroplysinin-1 and on breast cancer cell line MCF-7 by isofistularin-3. In this study, we also compared the cultivation of human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) on the A. aerophoba chitinous scaffolds, in comparison to chitin structures that were pre-coated with Geltrex™, an extracellular matrix mimetic which is used to enhance iPSC-CM adhesion. The iPSC-CMs on uncoated and pure chitin structures started contracting 24 h after seeding, with comparable behaviour observed on Geltrex-coated cell culture plates, confirming the biocompatibility of the sponge biomaterial with this cell type. The advantage of A. aerophoba is that this source organism does not need to be collected in large quantities to supply the necessary amount for further pre-clinical studies before chemical synthesis of the active compounds will be available. A preliminary analysis of marine sponge bioeconomy as a perspective direction for application of biomaterials and secondary bioactive metabolites has been finally performed for the first time.


Assuntos
Acetonitrilas , Alcaloides , Organismos Aquáticos/química , Materiais Biomiméticos , Cicloexenos , Células-Tronco Pluripotentes Induzidas/metabolismo , Miócitos Cardíacos/metabolismo , Poríferos/química , Acetonitrilas/química , Acetonitrilas/farmacocinética , Acetonitrilas/farmacologia , Alcaloides/química , Alcaloides/farmacocinética , Alcaloides/farmacologia , Animais , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacocinética , Materiais Biomiméticos/farmacologia , Linhagem Celular Tumoral , Cicloexenos/química , Cicloexenos/farmacocinética , Cicloexenos/farmacologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células MCF-7 , Miócitos Cardíacos/citologia
3.
PLoS One ; 13(5): e0195803, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29763421

RESUMO

Marine demosponges (Porifera: Demospongiae) are recognized as first metazoans which have developed over millions of years of evolution effective survival strategies based on unique metabolic pathways to produce both biologically active secondary metabolites and biopolymer-based stiff skeletons with 3D architecture. Up to date, among marine demosponges, only representatives of the Verongiida order have been known to synthetize biologically active substances as well as skeletons made of structural polysaccharide chitin. This work, to our knowledge, demonstrates for the first time that chitin is an important structural component within skeletons of non-verongiid demosponges Acarnus wolffgangi and Echinoclathria gibbosa collected in the Red Sea. Calcofluor white staining, FTIR and Raman analysis, ESI-MS, SEM, and fluorescence microscopy as well as a chitinase digestion assay were applied in order to confirm, with strong evidence, the finding of α-chitin in the skeleton of both species. We suggest that, the finding of chitin within these representatives of Poecilosclerida order is a promising step in the evaluation of these sponges as novel renewable sources for both biologically active metabolites and chitin, which are of prospective application for pharmacology and biomedicine.


Assuntos
Quitina/análise , Quitina/isolamento & purificação , Poríferos/metabolismo , Esqueleto/metabolismo , Animais , Quitina/metabolismo , Quitinases/metabolismo , Poríferos/anatomia & histologia , Esqueleto/anatomia & histologia
4.
J Struct Biol ; 183(3): 474-483, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23831449

RESUMO

This work demonstrates that chitin is an important structural component within the skeletal fibers of the freshwater sponge Spongilla lacustris. Using a variety of analytical techniques ((13)C solid state NMR, FT-IR, Raman, NEXAFS, ESI-MS, Morgan-Elson assay and Calcofluor White Staining); we show that this sponge chitin is much closer to α-chitin, known to be present in other animals, than to ß-chitin. Genetic analysis confirmed the presence of chitin synthases, which are described for the first time in a sponge. The presence of chitin in both marine (demosponges and hexactinellids) and freshwater sponges indicates that this important structural biopolymer was already present in their common ancestor.


Assuntos
Quitina/biossíntese , Poríferos/metabolismo , Acetilglucosamina/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Quitina/química , Quitina Sintase/química , Quitina Sintase/genética , Clonagem Molecular , Dados de Sequência Molecular , Poríferos/genética , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de Fourier , Espectroscopia por Absorção de Raios X
5.
Proc Biol Sci ; 280(1762): 20130339, 2013 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-23677340

RESUMO

A holdfast is a root- or basal plate-like structure of principal importance that anchors aquatic sessile organisms, including sponges, to hard substrates. There is to date little information about the nature and origin of sponges' holdfasts in both marine and freshwater environments. This work, to our knowledge, demonstrates for the first time that chitin is an important structural component within holdfasts of the endemic freshwater demosponge Lubomirskia baicalensis. Using a variety of techniques (near-edge X-ray absorption fine structure, Raman, electrospray ionization mas spectrometry, Morgan-Elson assay and Calcofluor White staining), we show that chitin from the sponge holdfast is much closer to α-chitin than to ß-chitin. Most of the three-dimensional fibrous skeleton of this sponge consists of spicule-containing proteinaceous spongin. Intriguingly, the chitinous holdfast is not spongin-based, and is ontogenetically the oldest part of the sponge body. Sequencing revealed the presence of four previously undescribed genes encoding chitin synthases in the L. baicalensis sponge. This discovery of chitin within freshwater sponge holdfasts highlights the novel and specific functions of this biopolymer within these ancient sessile invertebrates.


Assuntos
Quitina Sintase/genética , Quitina/química , Poríferos/química , Poríferos/genética , Acetilglucosamina/metabolismo , Sequência de Aminoácidos , Animais , Benzenossulfonatos/metabolismo , Quitina/metabolismo , Quitina Sintase/química , Quitina Sintase/metabolismo , Meios de Contraste/metabolismo , Lagos , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Poríferos/anatomia & histologia , Federação Russa , Alinhamento de Sequência , Espectrometria de Massas por Ionização por Electrospray , Análise Espectral Raman , Espectroscopia por Absorção de Raios X
6.
Zookeys ; (136): 13-21, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22140345

RESUMO

New hexactinellid sponges were collected from 2589 m depth on the Carlsberg Ridge in the Indian Ocean during deep-sea dredging. All fragments belong to a new genus and species, Indiellagen. n.ridgenensissp. n., a representative of the family Aulocalycidae described here. The peculiar features of this sponge, not described earlier for other Aulocalycidae, are: longitudinal strands present in several layers and epirhyses channelization.

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