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1.
Mol Cell ; 84(2): 375-385.e7, 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38103556

RESUMEN

Cyclic-oligonucleotide-based anti-phage signaling system (CBASS) is a common immune system that uses cyclic oligonucleotide signals to limit phage replication. In turn, phages encode anti-CBASS (Acb) proteins such as Acb2, which can sequester some cyclic dinucleotides (CDNs) and limit downstream effector activation. Here, we identified that Acb2 sequesters many CDNs produced by CBASS systems and inhibits stimulator of interferon genes (STING) activity in human cells. Surprisingly, the Acb2 hexamer also binds with high affinity to CBASS cyclic trinucleotides (CTNs) 3'3'3'-cyclic AMP-AMP-AMP and 3'3'3'-cAAG at a distinct site from CDNs. One Acb2 hexamer can simultaneously bind two CTNs and three CDNs. Phage-encoded Acb2 provides protection from type III-C CBASS that uses cA3 signaling molecules. Moreover, phylogenetic analysis of >2,000 Acb2 homologs encoded by diverse phages and prophages revealed that most are expected to bind both CTNs and CDNs. Altogether, Acb2 sequesters nearly all known CBASS signaling molecules through two distinct binding pockets and therefore serves as a broad-spectrum inhibitor of cGAS-based immunity.


Asunto(s)
Bacteriófagos , Nucleótidos Cíclicos , Humanos , Nucleótidos Cíclicos/metabolismo , Bacteriófagos/genética , Bacteriófagos/metabolismo , Filogenia , AMP Cíclico , Oligonucleótidos
2.
Annu Rev Microbiol ; 77: 23-43, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-36944261

RESUMEN

Small regulatory RNA (sRNAs) are key mediators of posttranscriptional gene control in bacteria. Assisted by RNA-binding proteins, a single sRNA often modulates the expression of dozens of genes, and thus sRNAs frequently adopt central roles in regulatory networks. Posttranscriptional regulation by sRNAs comes with several unique features that cannot be achieved by transcriptional regulators. However, for optimal network performance, transcriptional and posttranscriptional control mechanisms typically go hand-in-hand. This view is reflected by the ever-growing class of mixed network motifs involving sRNAs and transcription factors, which are ubiquitous in biology and whose regulatory properties we are beginning to understand. In addition, sRNA activity can be antagonized by base-pairing with sponge RNAs, adding yet another layer of complexity to these networks. In this article, we summarize the regulatory concepts underlying sRNA-mediated gene control in bacteria and discuss how sRNAs shape the output of a network, focusing on several key examples.


Asunto(s)
ARN Bacteriano , ARN Pequeño no Traducido , ARN Bacteriano/genética , ARN Bacteriano/metabolismo , Regulón , ARN Pequeño no Traducido/genética , ARN Pequeño no Traducido/metabolismo , Regulación Bacteriana de la Expresión Génica , Bacterias/genética , Bacterias/metabolismo , Bacterias Gramnegativas/genética , Bacterias Gramnegativas/metabolismo
3.
Mol Cell ; 77(2): 411-425.e7, 2020 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-31761494

RESUMEN

Base pairing RNAs modulate gene expression in all studied organisms. In many bacteria, the base pairing between most small regulatory RNAs (sRNAs) and their targets is mediated by the Hfq RNA chaperone. However, recent studies have shown FinO-domain proteins also bind sRNAs. To examine the global contribution of the FinO-domain ProQ protein in Escherichia coli, we carried out RIL-seq to identify RNA pairs bound to this protein. The RNA-RNA interactome for ProQ contains hundreds of pairs. Intriguingly, a significant fraction of the ProQ-bound RNA pairs are also found associated with Hfq, indicating overlapping, complementary, or competing roles for the two proteins. Characterization of one novel RNA pair bound by both chaperones revealed that while Hfq is required for RNA sponge-mediated downregulation of the sRNA, ProQ can inhibit this regulation. Overall, our results uncover increased complexity in RNA regulatory networks involving RNA chaperone proteins, RNases, sRNAs, and mRNAs.


Asunto(s)
ADN Bacteriano/genética , Proteínas de Escherichia coli/genética , Proteína de Factor 1 del Huésped/genética , ARN Bacteriano/genética , Proteínas de Unión al ARN/genética , Emparejamiento Base/genética , Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica/genética , Chaperonas Moleculares/genética , Dominios Proteicos/genética , ARN Mensajero/genética , ARN Pequeño no Traducido/genética
4.
Proc Natl Acad Sci U S A ; 120(9): e2220934120, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36802428

RESUMEN

Sea sponges are the largest marine source of small-molecule natural products described to date. Sponge-derived molecules, such as the chemotherapeutic eribulin, the calcium-channel blocker manoalide, and antimalarial compound kalihinol A, are renowned for their impressive medicinal, chemical, and biological properties. Sponges contain microbiomes that control the production of many natural products isolated from these marine invertebrates. In fact, all genomic studies to date investigating the metabolic origins of sponge-derived small molecules concluded that microbes-not the sponge animal host-are the biosynthetic producers. However, early cell-sorting studies suggested the sponge animal host may play a role particularly in the production of terpenoid molecules. To investigate the genetic underpinnings of sponge terpenoid biosynthesis, we sequenced the metagenome and transcriptome of an isonitrile sesquiterpenoid-containing sponge of the order Bubarida. Using bioinformatic searches and biochemical validation, we identified a group of type I terpene synthases (TSs) from this sponge and multiple other species, the first of this enzyme class characterized from the sponge holobiome. The Bubarida TS-associated contigs consist of intron-containing genes homologous to sponge genes and feature GC percentage and coverage consistent with other eukaryotic sequences. We identified and characterized TS homologs from five different sponge species isolated from geographically distant locations, thereby suggesting a broad distribution amongst sponges. This work sheds light on the role of sponges in secondary metabolite production and speaks to the possibility that other sponge-specific molecules originate from the animal host.


Asunto(s)
Productos Biológicos , Microbiota , Poríferos , Animales , Poríferos/genética , Organismos Acuáticos/genética , Microbiota/genética , Metagenoma , Filogenia
5.
Proc Natl Acad Sci U S A ; 120(40): e2311755120, 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37748078

RESUMEN

Soft materials that can produce electrical energy under mechanical stimulus or deform significantly via moderate electrical fields are important for applications ranging from soft robotics to biomedical science. Piezoelectricity, the property that would ostensibly promise such a realization, is notably absent from typical soft matter. Flexoelectricity is an alternative form of electromechanical coupling that universally exists in all dielectrics and can generate electricity under nonuniform deformation such as flexure and conversely, a deformation under inhomogeneous electrical fields. The flexoelectric coupling effect is, however, rather modest for most materials and thus remains a critical bottleneck. In this work, we argue that a significant emergent flexoelectric response can be obtained by leveraging a hierarchical porous structure found in biological materials. We experimentally illustrate our thesis for a natural dry luffa vegetable-based sponge and demonstrate an extraordinarily large mass- and deformability-specific electromechanical response with the highest-density-specific equivalent piezoelectric coefficient known for any material (50 times that of polyvinylidene fluoride and more than 10 times that of lead zirconate titanate). Finally, we demonstrate the application of the fabricated natural sponge as green, biodegradable flexible smart devices in the context of sensing (e.g., for speech, touch pressure) and electrical energy harvesting.

6.
EMBO J ; 40(15): e107976, 2021 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-34184765

RESUMEN

Nuclear stress bodies (nSBs) are nuclear membraneless organelles formed around stress-inducible HSATIII architectural long noncoding RNAs (lncRNAs). nSBs repress splicing of hundreds of introns during thermal stress recovery, which are partly regulated by CLK1 kinase phosphorylation of temperature-dependent Ser/Arg-rich splicing factors (SRSFs). Here, we report a distinct mechanism for this splicing repression through protein sequestration by nSBs. Comprehensive identification of RNA-binding proteins revealed HSATIII association with proteins related to N6 -methyladenosine (m6 A) RNA modification. 11% of the first adenosine in the repetitive HSATIII sequence were m6 A-modified. nSBs sequester the m6 A writer complex to methylate HSATIII, leading to subsequent sequestration of the nuclear m6 A reader, YTHDC1. Sequestration of these factors from the nucleoplasm represses m6 A modification of pre-mRNAs, leading to repression of m6 A-dependent splicing during stress recovery phase. Thus, nSBs serve as a common platform for regulation of temperature-dependent splicing through dual mechanisms employing two distinct ribonucleoprotein modules with partially m6 A-modified architectural lncRNAs.


Asunto(s)
Proteínas del Tejido Nervioso/genética , Factores de Empalme de ARN/genética , Empalme del ARN , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Adenosina/análogos & derivados , Adenosina/metabolismo , Núcleo Celular/genética , Células HeLa , Humanos , Proteínas del Tejido Nervioso/metabolismo , Fosforilación , Proteínas Serina-Treonina Quinasas/genética , Proteínas Tirosina Quinasas/genética , Factores de Empalme de ARN/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Secuencias Repetitivas de Ácidos Nucleicos , Factores de Empalme Serina-Arginina/genética , Factores de Empalme Serina-Arginina/metabolismo , Temperatura
7.
Proc Natl Acad Sci U S A ; 119(21): e2117349119, 2022 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-35584119

RESUMEN

The Rhodopsin family of G-protein­coupled receptors (GPCRs) comprises the targets of nearly a third of all pharmaceuticals. Despite structural water present in GPCR X-ray structures, the physiological relevance of these solvent molecules to rhodopsin signaling remains unknown. Here, we show experimental results consistent with the idea that rhodopsin activation in lipid membranes is coupled to bulk water movements into the protein. To quantify hydration changes, we measured reversible shifting of the metarhodopsin equilibrium due to osmotic stress using an extensive series of polyethylene glycol (PEG) osmolytes. We discovered clear evidence that light activation entails a large influx of bulk water (∼80­100 molecules) into the protein, giving insight into GPCR activation mechanisms. Various size polymer osmolytes directly control rhodopsin activation, in which large solutes are excluded from rhodopsin and dehydrate the protein, favoring the inactive state. In contrast, small osmolytes initially forward shift the activation equilibrium until a quantifiable saturation point is reached, similar to gain-of-function protein mutations. For the limit of increasing osmolyte size, a universal response of rhodopsin to osmotic stress is observed, suggesting it adopts a dynamic, hydrated sponge-like state upon photoactivation. Our results demand a rethinking of the role of water dynamics in modulating various intermediates in the GPCR energy landscape. We propose that besides bound water, an influx of bulk water plays a necessary role in establishing the active GPCR conformation that mediates signaling.


Asunto(s)
Receptores Acoplados a Proteínas G , Rodopsina , Conformación Proteica , Receptores Acoplados a Proteínas G/metabolismo , Rodopsina/metabolismo , Solventes/química , Agua/química
8.
Nano Lett ; 24(30): 9178-9185, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39017609

RESUMEN

Lithium (Li) dendritic growth and huge volume expansion seriously hamper Li-metal anode development. Herein, we design a lightweight 3D Li-ion-affinity host enabled by silver (Ag) nanoparticles fully decorating a porous melamine sponge (Ag@PMS) for dendrite-free and high-areal-capacity Li anodes. The compact Ag nanoparticles provide abundant preferred nucleation sites and give the host strong conductivity. Moreover, the high specific surface area and polar groups of the elastic, porous melamine sponge enhance the Li-ion diffusion kinetics, prompting homogeneity of Li deposition and stripping. As expected, the integrated 3D Ag@PMS-Li anode delivered a remarkable electrochemical performance, with a Coulombic efficiency (CE) of 97.14% after 450 cycles at 1 mA cm-2. The symmetric cell showed an ultralong lifespan of 3400 h at 1 mA cm-2 for 1 mAh cm-2. This study provides a facile and cost-effective strategy to design an advanced 3D framework for the preparation of a stable dendrite-free Li metal anode.

9.
Nano Lett ; 24(17): 5260-5269, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38639406

RESUMEN

High-temperature affordable flexible polymer-based pressure sensors integrated with repeatable early fire warning service are strongly desired for harsh environmental applications, yet their creation remains challenging. This work proposed an approach for preparing such advanced integrated sensors based on silver nanoparticles and an ammonium polyphosphate (APP)-modified laminar-structured bulk wood sponge (APP/Ag@WS). Such integrated sensors demonstrated excellent fire warning performance, including a short response time (minimum of 0.44 s), a long-lasting alarm time (>750 s), and reliable repeatability. Moreover, it achieved high-temperature affordable flexible pressure sensing that exhibited an almost unimpaired working range of 0-7.5 kPa and a higher sensitivity (in the low-pressure range, maximum to 226.03 kPa-1) after fire. The high stability was attributed to reliable structural elasticity, and the wood-derived amorphous carbon is capable of repeatable fire warnings. Finally, a Ag@APP/WS-based wireless fire alarm system that realized reliable house fire accident detection was demonstrated, showing great promise for smart firefighting application.

10.
J Bacteriol ; 206(8): e0004924, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-38980083

RESUMEN

The small RNA (sRNA) RydC strongly activates cfa, which encodes the cyclopropane fatty acid synthase. Previous work demonstrated that RydC activation of cfa increases the conversion of unsaturated fatty acids to cyclopropanated fatty acids in membrane lipids and changes the biophysical properties of membranes, making cells more resistant to acid stress. The regulators that control RydC synthesis had not previously been identified. In this study, we identify a GntR-family transcription factor, YieP, that represses rydC transcription. YieP positively autoregulates its own transcription and indirectly regulates cfa through RydC. We further identify additional sRNA regulatory inputs that contribute to the control of RydC and cfa. The translation of yieP is repressed by the Fnr-dependent sRNA, FnrS, making FnrS an indirect activator of rydC and cfa. Conversely, RydC activity on cfa is antagonized by the OmpR-dependent sRNA OmrB. Altogether, this work illuminates a complex regulatory network involving transcriptional and post-transcriptional inputs that link the control of membrane biophysical properties to multiple environmental signals. IMPORTANCE: Bacteria experience many environmental stresses that challenge their membrane integrity. To withstand these challenges, bacteria sense what stress is occurring and mount a response that protects membranes. Previous work documented the important roles of small RNA (sRNA) regulators in membrane stress responses. One sRNA, RydC, helps cells cope with membrane-disrupting stresses by promoting changes in the types of lipids incorporated into membranes. In this study, we identified a regulator, YieP, that controls when RydC is produced and additional sRNA regulators that modulate YieP levels and RydC activity. These findings illuminate a complex regulatory network that helps bacteria sense and respond to membrane stress.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Regulación Bacteriana de la Expresión Génica , ARN Bacteriano , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , ARN Bacteriano/metabolismo , ARN Bacteriano/genética , Transcripción Genética , ARN Pequeño no Traducido/genética , ARN Pequeño no Traducido/metabolismo , Ácido Graso Sintasas/metabolismo , Ácido Graso Sintasas/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Ciclopropanos , Ácidos Grasos , Metiltransferasas
11.
BMC Bioinformatics ; 25(1): 53, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302900

RESUMEN

BACKGROUND: Non-coding RNAs represent a large part of the human transcriptome and have been shown to play an important role in disease such as cancer. However, their biological functions are still incompletely understood. Among non-coding RNAs, circular RNAs (circRNAs) have recently been identified for their microRNA (miRNA) sponge function which allows them to modulate the expression of miRNA target genes by taking on the role of competitive endogenous RNAs (ce-circRNAs). Today, most computational tools are not adapted to the search for ce-circRNAs or have not been developed for the search for ce-circRNAs from user's transcriptomic data. RESULTS: In this study, we present Cirscan (CIRcular RNA Sponge CANdidates), an interactive Shiny application that automatically infers circRNA-miRNA-mRNA networks from human multi-level transcript expression data from two biological conditions (e.g. tumor versus normal conditions in the case of cancer study) in order to identify on a large scale, potential sponge mechanisms active in a specific condition. Cirscan ranks each circRNA-miRNA-mRNA subnetwork according to a sponge score that integrates multiple criteria based on interaction reliability and expression level. Finally, the top ranked sponge mechanisms can be visualized as networks and an enrichment analysis is performed to help its biological interpretation. We showed on two real case studies that Cirscan is capable of retrieving sponge mechanisms previously described, as well as identifying potential novel circRNA sponge candidates. CONCLUSIONS: Cirscan can be considered as a companion tool for biologists, facilitating their ability to prioritize sponge mechanisms for experimental validations and identifying potential therapeutic targets. Cirscan is implemented in R, released under the license GPL-3 and accessible on GitLab ( https://gitlab.com/geobioinfo/cirscan_Rshiny ). The scripts used in this paper are also provided on Gitlab ( https://gitlab.com/geobioinfo/cirscan_paper ).


Asunto(s)
MicroARNs , Neoplasias , Humanos , MicroARNs/genética , MicroARNs/metabolismo , ARN Circular/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reproducibilidad de los Resultados , Redes Reguladoras de Genes
12.
J Biol Chem ; 299(4): 103050, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36813233

RESUMEN

Consecutive oxygenation of arachidonic acid by 5-lipoxygenase and cyclooxygenase-2 yields the hemiketal eicosanoids, HKE2 and HKD2. Hemiketals stimulate angiogenesis by inducing endothelial cell tubulogenesis in culture; however, how this process is regulated has not been determined. Here, we identify vascular endothelial growth factor receptor 2 (VEGFR2) as a mediator of HKE2-induced angiogenesis in vitro and in vivo. We found that HKE2 treatment of human umbilical vein endothelial cells dose-dependently increased the phosphorylation of VEGFR2 and the downstream kinases ERK and Akt that mediated endothelial cell tubulogenesis. In vivo, HKE2 induced the growth of blood vessels into polyacetal sponges implanted in mice. HKE2-mediated effects in vitro and in vivo were blocked by the VEGFR2 inhibitor vatalanib, indicating that the pro-angiogenic effect of HKE2 was mediated by VEGFR2. HKE2 covalently bound and inhibited PTP1B, a protein tyrosine phosphatase that dephosphorylates VEGFR2, thereby providing a possible molecular mechanism for how HKE2 induced pro-angiogenic signaling. In summary, our studies indicate that biosynthetic cross-over of the 5-lipoxygenase and cyclooxygenase-2 pathways gives rise to a potent lipid autacoid that regulates endothelial cell function in vitro and in vivo. These findings suggest that common drugs targeting the arachidonic acid pathway could prove useful in antiangiogenic therapy.


Asunto(s)
Araquidonato 5-Lipooxigenasa , Receptor 2 de Factores de Crecimiento Endotelial Vascular , Ratones , Humanos , Animales , Ciclooxigenasa 2/metabolismo , Ácido Araquidónico , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Neovascularización Fisiológica , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Inhibidores de la Angiogénesis/farmacología , Movimiento Celular , Proliferación Celular
13.
Mol Cancer ; 23(1): 4, 2024 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-38184608

RESUMEN

BACKGROUND: Renal cell carcinoma (RCC) is one of the most common malignant tumor worldwide. Metastasis is a leading case of cancer-related deaths of RCC. Circular RNAs (circRNAs), a class of noncoding RNAs, have emerged as important regulators in cancer metastasis. However, the functional effects and regulatory mechanisms of circRNAs on RCC metastasis remain largely unknown. METHODS: High-throughput RNA sequencing techniques were performed to analyze the expression profiles of circRNAs and mRNAs in highly and poorly invasive clear cell renal cell carcinoma (ccRCC) cell lines. Functional experiments were performed to unveil the regulatory role of circPPAP2B in the proliferation and metastatic capabilities of ccRCC cells. RNA pulldown, Mass spectrometry analysis, RNA methylation immunoprecipitation (MeRIP), RNA immunoprecipitation (RIP), co-immunoprecipitation (CoIP), next-generation RNA-sequencing and double luciferase experiments were employed to clarify the molecular mechanisms by which circPPAP2B promotes ccRCC metastasis. RESULTS: In this study, we describe a newly identified circular RNA called circPPAP2B, which is overexpressed in highly invasive ccRCC cells, as determined through advanced high-throughput RNA sequencing techniques. Furthermore, we observed elevated circPPAP2B in ccRCC tissues, particularly in metastatic ccRCC tissues, and found it to be associated with poor prognosis. Functional experiments unveiled that circPPAP2B actively stimulates the proliferation and metastatic capabilities of ccRCC cells. Mechanistically, circPPAP2B interacts with HNRNPC in a m6A-dependent manner to facilitate HNRNPC nuclear translocation. Subcellular relocalization was dependent upon nondegradable ubiquitination of HNRNPC and stabilization of an HNRNPC/Vimentin/Importin α7 ternary complex. Moreover, we found that circPPAP2B modulates the interaction between HNRNPC and splicing factors, PTBP1 and HNPNPK, and regulates pre-mRNA alternative splicing. Finally, our studies demonstrate that circPPAP2B functions as a miRNA sponge to directly bind to miR-182-5p and increase CYP1B1 expression in ccRCC. CONCLUSIONS: Collectively, our study provides comprehensive evidence that circPPAP2B promotes proliferation and metastasis of ccRCC via HNRNPC-dependent alternative splicing and miR-182-5p/CYP1B1 axis and highlights circPPAP2B as a potential therapeutic target for ccRCC intervention.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , MicroARNs , Humanos , Carcinoma de Células Renales/genética , Empalme Alternativo , ARN Circular/genética , MicroARNs/genética , Neoplasias Renales/genética , Ribonucleoproteínas Nucleares Heterogéneas , Proteína de Unión al Tracto de Polipirimidina , Citocromo P-450 CYP1B1 , Ribonucleoproteína Heterogénea-Nuclear Grupo C/genética
14.
Plant Cell Physiol ; 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38808931

RESUMEN

Transposable elements (TEs) are mobile DNA elements that are particularly abundant in the plant genomes. They have long been considered as junk DNA; however, a growing body of evidence suggests that TE insertions promote genetic diversity that is essential for the adaptive evolution of a species. Thus far, studies have mainly investigated the cis-acting regulatory roles of TEs generated by their insertions nearby or within the host genes. However, the trans-acting effects of TE-derived RNA and DNA remained obscure to date. TEs contain various regulatory elements within their sequences that can accommodate the binding of specific RNAs and proteins. Recently, it was suggested that some of these cellular regulators are shared between TEs and the host genes, and the competition for the common host factors underlies the fine-tuned developmental reprogramming. In this review, we will highlight and discuss the latest discoveries on the biological functions of plant TEs, with a particular focus on their competitive binding with specific developmental regulators.

15.
Microbiology (Reading) ; 170(7)2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39073401

RESUMEN

Sponges (phylum Porifera) harbour specific microbial communities that drive the ecology and evolution of the host. Understanding the structure and dynamics of these communities is emerging as a primary focus in marine microbial ecology research. Much of the work to date has focused on sponges from warm and shallow coastal waters, while sponges from the deep ocean remain less well studied. Here, we present a metataxonomic analysis of the microbial consortia associated with 23 individual deep-sea sponges. We identify a high abundance of archaea relative to bacteria across these communities, with certain sponge microbiomes comprising more than 90 % archaea. Specifically, the archaeal family Nitrosopumilaceae is prolific, comprising over 99 % of all archaeal reads. Our analysis revealed that sponge microbial communities reflect the host sponge phylogeny, indicating a key role for host taxonomy in defining microbiome composition. Our work confirms the contribution of both evolutionary and environmental processes to the composition of microbial communities in deep-sea sponges.


Asunto(s)
Archaea , Bacterias , Microbiota , Filogenia , Poríferos , Poríferos/microbiología , Archaea/clasificación , Archaea/genética , Archaea/aislamiento & purificación , Animales , Océano Atlántico , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Agua de Mar/microbiología , ARN Ribosómico 16S/genética , Biodiversidad
16.
Small ; 20(7): e2304754, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37632311

RESUMEN

Microbial fuel cells (MFCs) are of great potential for wastewater remediation and chemical energy recovery. Nevertheless, limited by inefficient electron transfer between microorganisms and electrode, the remediation capacity and output power density of MFCs are still far away from the demand of practical application. Herein, a pore-matching strategy is reported to develop uniform electroactive biofilms by inoculating microorganisms inside a pore-matched sponge, which is assembled of core-shell polyaniline@carbon nanotube (PANI@CNT). The maximum power density achieved by the PANI@CNT bioanode is 7549.4 ± 27.6 mW m-2 , which is higher than the excellent MFCs with proton exchange membrane reported to date, while the coulombic efficiency also attains a considerable 91.7 ± 1.2%. The PANI@CNT sponge enriches the exoelectrogen Geobacter significantly, and is proved to play the role of conductive pili in direct electron transfer as it down-regulates the gene encoding pilA. This work exemplifies a practicable strategy to develop excellent bioanode to boost electron extraction in MFCs and provides in-depth insights into the enhancement mechanism.


Asunto(s)
Compuestos de Anilina , Fuentes de Energía Bioeléctrica , Nanotubos de Carbono , Electrones , Transporte de Electrón , Fimbrias Bacterianas , Conductividad Eléctrica , Electrodos , Nanotubos de Carbono/química
17.
Small ; 20(5): e2305136, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37759415

RESUMEN

This work addresses the challenges in developing carbon fiber paper-based supercapacitors (SCs) with high energy density by focusing on the limited capacity of carbon fiber. To overcome this limitation, a sponge-like porous carbon fiber paper enriched with oxygen functional groups (OFGs) is prepared, and Cu(OH)2 nanorods are grown on its surface to construct the SC anode. This design results in a multi-layered carbon fiber paper-based electrode with a specific structure and enhanced capacitance. The Cu(OH)2 @PCFP anode exhibits an areal capacitance of 547.83 mF cm-2 at a current density of 1 mA cm-2 and demonstrates excellent capacitance retention of 99.8% after 10 000 cycles. Theoretical calculations further confirm that the Cu(OH)2 /OFGs-graphite heterostructure exhibits higher conductivity, facilitating faster charge transfer. A solid-state SC is successfully assembled using Ketjen Black@PCFP as the cathode and KOH/PVA as the gel electrolyte. The resulting device exhibits an energy density of 0.21 Wh cm-2 at 1.50 mW cm-2 , surpassing the performance of reported Cu(OH)2 SCs. This approach, combining materials design with an understanding of underlying mechanisms, not only expands the range of electrode materials but also provides valuable insights for the development of high-capacity energy storage devices.

18.
Small ; : e2401939, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38924354

RESUMEN

3D carbon-based porous sponges are recognized for significant potential in oil absorption and electromagnetic interference (EMI). However, their widespread application is hindered by a common compromise between high performance and affordability of mass production. Herein, a novel approach is introduced that involves laser-assisted micro-zone heating melt-blown spinning (LMHMS) to address this challenge by creating pitch-based submicron carbon fibers (PSCFs) sponge with 3D interconnected structures. These structures bestow the resulting sponge exceptional characteristics including low density (≈20 mg cm-3), high porosity (≈99%), remarkable compressibility (80% maximum strain), and superior conductivity (≈628 S m-1). The resultant PSCF sponges realize an oil/organic solvent sorption capacity over 56 g/g and possess remarkable regenerated ability. In addition to their effectiveness in cleaning up oil/organic solvent spills, they also demonstrated strong electromagnetic shielding capabilities, with a total shielding effectiveness (SE) exceeding 60 dB across the X-band GHz range. In virtue of extreme lightweight of ≈20 mg cm-3, the specific SE of the PSCF sponge reaches as high as ≈1466 dB cm3 g-1, surpassing the performance of numerous carbon-based porous structures. Thus, the unique blend of properties renders these sponges promising for transforming strategies in addressing oil/organic solvent contaminations and providing effective protection against EMI.

19.
J Transl Med ; 22(1): 207, 2024 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-38414006

RESUMEN

With an estimated one million new cases reported annually, gastric cancer (GC) ranks as the fifth most diagnosed malignancy worldwide. The early detection of GC remains a major challenge, and the prognosis worsens either when patients develop resistance to chemotherapy or radiotherapy or when the cancer metastasizes. The precise pathogenesis underlying GC is not well understood, which further complicates its treatment. Circular RNAs (circRNAs), a recently discovered class of noncoding RNAs that originate from parental genes through "back-splicing", have been shown to play a key role in various biological processes in both eukaryotes and prokaryotes. CircRNAs have been linked to cardiovascular diseases, diabetes, hypertension, Alzheimer's disease, and the occurrence and progression of tumors. Prior studies have established that circRNAs play a crucial role in GC, impacting tumorigenesis, diagnosis, progression, and therapy resistance. This review aims to summarize how circRNAs contribute to GC tumorigenesis and progression, examine their roles in the development of drug resistance, discuss their potential as biotechnological drugs, and summarize their response to therapeutic drugs and microorganism in GC.


Asunto(s)
ARN Circular , Neoplasias Gástricas , Humanos , ARN Circular/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , Neoplasias Gástricas/diagnóstico , Pronóstico , Carcinogénesis/genética , Transformación Celular Neoplásica
20.
BMC Microbiol ; 24(1): 315, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39192220

RESUMEN

The Red Sea is a promising habitat for the discovery of new bioactive marine natural products. Sponges associated microorganisms represent a wealthy source of compounds with unique chemical structures and diverse biological activities. Metagenomics is an important omics-based culture-independent technique that is used as an effective tool to get genomic and functional information on sponge symbionts. In this study, we used metagenomic analysis of two Egyptian Red Sea sponges Hyrtios erectus and Phorbas topsenti microbiomes to study the biodiversity and the biosynthetic potential of the Red Sea sponges to produce bioactive compounds. Our data revealed high biodiversity of the two sponges' microbiota with phylum Proteobacteria as the most dominant phylum in the associated microbial community with an average of 31% and 70% respectively. The analysis also revealed high biosynthetic potential of sponge Hyrtios erectus microbiome through detecting diverse types of biosynthetic gene clusters (BGCs) with predicted cytotoxic, antibacterial and inhibitory action. Most of these BGCs were predicted to be novel as they did not show any similarity with any MIBiG database known cluster. This study highlights the importance of the microbiome of the collected Red Sea sponge Hyrtios erectus as a valuable source of new bioactive natural products.


Asunto(s)
Metagenómica , Microbiota , Poríferos , Poríferos/microbiología , Animales , Océano Índico , Microbiota/genética , Egipto , Bacterias/genética , Bacterias/clasificación , Filogenia , Biodiversidad , Familia de Multigenes , Productos Biológicos/metabolismo , Metagenoma , Proteobacteria/genética , Proteobacteria/clasificación , Proteobacteria/aislamiento & purificación
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