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1.
Mar Drugs ; 20(4)2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35447941

RESUMO

Ovothiols are histidine-derived thiols produced by a variety of marine invertebrates, protists and bacteria. These compounds, which are among the strongest natural antioxidants, are involved in controlling the cellular redox balance due to their redox exchange with glutathione. Although ovothiols were initially reported as protective agents against environmental stressors, new evidence suggests that they can also act as pheromones and participate in fundamental biological processes such as embryogenesis. To get further insight into the biological roles of ovothiols, we compared ovothiol biosynthesis in the sea urchin Paracentrotus lividus and in the mussel Mytilus galloprovincialis, the two species that represent the richest sources of these compounds among marine invertebrates. Ovothiol content was measured in different tissues and in the immune cells from both species and the expression levels of ovoA, the gene responsible for ovothiol biosynthesis, was inferred from publicly available transcriptomes. A comparative analysis of ovothiol biosynthesis in the two species allowed the identification of the tissues and cells synthesizing the metabolite and highlighted analogies and differences between sea urchins and mussels. By improving our knowledge on the biological roles of ovothiols and pointing out the existence of sustainable natural sources for their isolation, this study provides the basis for future biotechnological investigations on these valuable compounds.


Assuntos
Metilistidinas , Paracentrotus , Animais , Organismos Aquáticos/metabolismo , Expressão Gênica , Paracentrotus/genética , Paracentrotus/metabolismo , Ouriços-do-Mar/genética , Ouriços-do-Mar/metabolismo
2.
Nucleic Acids Res ; 47(15): 8318-8331, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31276595

RESUMO

The G-quadruplex-forming VEGF-binding aptamer V7t1 was previously found to be highly polymorphic in a K+-containing solution and, to restrict its conformational preferences to a unique, well-defined form, modified nucleotides (LNA and/or UNA) were inserted in its sequence. We here report an in-depth biophysical characterization of V7t1 in a Na+-rich medium, mimicking the extracellular environment in which VEGF targeting should occur, carried out combining several techniques to analyse the conformational behaviour of the aptamer and its binding to the protein. Our results demonstrate that, in the presence of high Na+ concentrations, V7t1 behaves in a very different way if subjected or not to annealing procedures, as evidenced by native gel electrophoresis, size exclusion chromatography and dynamic light scattering analysis. Indeed, not-annealed V7t1 forms both monomeric and dimeric G-quadruplexes, while the annealed oligonucleotide is a monomeric species. Remarkably, only the dimeric aptamer efficiently binds VEGF, showing higher affinity for the protein compared to the monomeric species. These findings provide new precious information for the development of improved V7t1 analogues, allowing more efficient binding to the cancer-related protein and the design of effective biosensors or theranostic devices based on VEGF targeting.


Assuntos
Aptâmeros de Nucleotídeos/metabolismo , Quadruplex G , Oligonucleotídeos/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Ligação Competitiva , Dicroísmo Circular , Conformação de Ácido Nucleico , Oligonucleotídeos/química , Oligonucleotídeos/genética , Potássio/química , Potássio/metabolismo , Ligação Proteica , Sódio/química , Sódio/metabolismo , Espectrofotometria Ultravioleta , Fator A de Crescimento do Endotélio Vascular/genética
3.
Prep Biochem Biotechnol ; 51(6): 562-569, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33095097

RESUMO

Hepatitis E virus (HEV) is a nonenveloped virus causing an emerging zoonotic disease posing a severe threat to the public health in the world, especially to pregnant women. In this study, a truncated form (aa 368-606) of the open reading frame 2 of the capsid protein (tORF2-HEV), a major structural protein of HEV, was expressed in Escherichia coli. This work characterizes for the first time, the fused Glutathione-S-Transferase-tagged tORF2 (GST-tORF2) and tORF2-HEV forms in E. coli. The fusion protein was purified by affinity chromatography with a purity higher than 90% and to yield about 27% after thrombin digestion. The purified GST-tORF2 protein was then characterized by western blot, using anti-GST antibodies, and CD spectroscopy. The GST-tORF2 and tORF2-HEV proteins were shown to be efficient to develop an ELISA test to detect anti-HEV IgG in mice sera immunized with a recombinant full length ORF2 protein. Sera showed a significant increase of the absorbance signal at 450 nm, in plate wells coated with a quantity of 0.5, 1 and 2 µg of proteins. ELISA plates coated with the purified GST-tORF2 and tORF2-HEV showed similar response when compared to the HEV ELISA where total insect cell lysate, infected with the recombinant baculovirus expressing full ORF2, was used as positive control.


Assuntos
Proteínas do Capsídeo , Vírus da Hepatite E , Proteínas Recombinantes de Fusão , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/isolamento & purificação , Escherichia coli/genética , Escherichia coli/metabolismo , Vírus da Hepatite E/química , Vírus da Hepatite E/genética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação
4.
Mol Cell Biochem ; 451(1-2): 165-171, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30014221

RESUMO

The reaction of free amino groups in proteins with reactive carbonyl species, known as glycation, leads to the formation of mixtures of products, collectively referred to as advanced glycation endproducts (AGEs). These compounds have been implicated in several important diseases, but their role in pathogenesis and clinical symptoms' development is still debated. Particularly, AGEs are often associated to the formation of amyloid deposits in conformational diseases, such as Alzheimer's and Parkinson's disease, and it has been suggested that they might influence the mechanisms and kinetics of protein aggregation. We here present the characterization of the products of glycation of the model protein MNEI with methylglyoxal and their effect on the protein structure. We demonstrate that, despite being an uncontrolled process, glycation occurs only at specific residues of the protein. Moreover, while not affecting the protein fold, it alters its shape and hydrodynamic properties and increases its tendency to fibrillar aggregation. Our study opens the way to in deep structural investigations to shed light on the complex link between protein post-translational modifications, structure, and stability.


Assuntos
Amiloide/química , Proteínas de Plantas/química , Agregados Proteicos , Processamento de Proteína Pós-Traducional , Aldeído Pirúvico/química , Glicosilação , Proteínas de Plantas/metabolismo , Aldeído Pirúvico/metabolismo
5.
Planta ; 248(2): 465-476, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29777363

RESUMO

MAIN CONCLUSION: Plastid-based MNEI protein mutants retain the structure, stability and sweetness of their bacterial counterparts, confirming the attractiveness of the plastid transformation technology for high-yield production of recombinant proteins. The prevalence of obesity and diabetes has dramatically increased the industrial demand for the development and use of alternatives to sugar and traditional sweeteners. Sweet proteins, such as MNEI, a single chain derivative of monellin, are the most promising candidates for industrial applications. In this work, we describe the use of tobacco chloroplasts as a stable plant expression platform to produce three MNEI protein mutants with improved taste profile and stability. All plant-based proteins were correctly expressed in tobacco chloroplasts, purified and subjected to in-depth chemical and sensory analyses. Recombinant MNEI mutants showed a protein yield ranging from 5% to more than 50% of total soluble proteins, which, to date, represents the highest accumulation level of MNEI mutants in plants. Comparative analyses demonstrated the high similarity, in terms of structure, stability and function, of the proteins produced in plant chloroplasts and bacteria. The high yield and the extreme sweetness perceived for the plant-derived proteins prove that plastid transformation technology is a safe, stable and cost-effective production platform for low-calorie sweeteners, with an estimated production of up to 25-30 mg of pure protein/plant.


Assuntos
Nicotiana/metabolismo , Edulcorantes/metabolismo , Cloroplastos/metabolismo , Expressão Gênica , Vetores Genéticos/genética , Proteínas Mutantes , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Proteínas Recombinantes , Edulcorantes/isolamento & purificação , Paladar , Nicotiana/genética , Transformação Genética
6.
Biochim Biophys Acta Gen Subj ; 1862(4): 808-815, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29288772

RESUMO

BACKGROUND: MNEI and its variant Y65R-MNEI are sweet proteins with potential applications as sweeteners in food industry. Also, they are often used as model systems for folding and aggregation studies. METHODS: X-ray crystallography was used to structurally characterize Y65R-MNEI at five different pHs, while circular dichroism and fluorescence spectroscopy were used to study their thermal and chemical stability. ThT assay and AFM were used for studying the kinetics of aggregation and morphology of the aggregates. RESULTS: Crystal structures of Y65R-MNEI revealed the existence of a dimer in the asymmetric unit, which, depending on the pH, assumes either an open or a closed conformation. The pH dramatically affects kinetics of formation and morphology of the aggregates: both MNEI and Y65R-MNEI form fibrils at acidic pH while amorphous aggregates are observed at neutral pH. CONCLUSIONS: The mutation Y65R induces structural modifications at the C-terminal region of the protein, which account for the decreased stability of the mutant when compared to MNEI. Furthermore, the pH-dependent conformation of the Y65R-MNEI dimer may explain the different type of aggregates formed as a function of pH. GENERAL SIGNIFICANCE: The investigation of the structural bases of aggregation gets us closer to the possibility of controlling such process, either by tuning the physicochemical environmental parameters or by site directed mutagenesis. This knowledge is helpful to expand the range of stability of proteins with potential industrial applications, such as MNEI and its mutant Y65R-MNEI, which should ideally preserve their structure and soluble state through a wide array of conditions.


Assuntos
Proteínas Mutantes/química , Proteínas de Plantas/química , Conformação Proteica , Edulcorantes/química , Dicroísmo Circular , Cristalografia por Raios X , Concentração de Íons de Hidrogênio , Cinética , Microscopia de Força Atômica , Modelos Moleculares , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Mutação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Agregados Proteicos , Desnaturação Proteica , Multimerização Proteica , Edulcorantes/metabolismo
7.
Microb Cell Fact ; 17(1): 126, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30111331

RESUMO

BACKGROUND: Recent biotechnological advancements have allowed for the adoption of Lactococcus lactis, a typical component of starter cultures used in food industry, as the host for the production of food-grade recombinant targets. Among several advantages, L. lactis has the important feature of growing on lactose, the main carbohydrate in milk and a majoritarian component of dairy wastes, such as cheese whey. RESULTS: We have used recombinant L. lactis NZ9000 carrying the nisin inducible pNZ8148 vector to produce MNEI, a small sweet protein derived from monellin, with potential for food industry applications as a high intensity sweetener. We have been able to sustain this production using a medium based on the cheese whey from the production of ricotta cheese, with minimal pre-treatment of the waste. As a proof of concept, we have also tested these conditions for the production of MMP-9, a protein that had been previously successfully obtained from L. lactis cultures in standard growth conditions. CONCLUSIONS: Other than presenting a new system for the recombinant production of MNEI, more compliant with its potential applications in food industry, our results introduce a strategy to valorize dairy effluents through the synthesis of high added value recombinant proteins. Interestingly, the possibility of using this whey-derived medium relied greatly on the choice of the appropriate codon usage for the target gene. In fact, when a gene optimized for L. lactis was used, the production of MNEI proceeded with good yields. On the other hand, when an E. coli optimized gene was employed, protein synthesis was greatly reduced, to the point of being completely abated in the cheese whey-based medium. The production of MMP-9 was comparable to what observed in the reference conditions.


Assuntos
Queijo/microbiologia , Lactococcus lactis/metabolismo , Proteínas/metabolismo , Soro do Leite/metabolismo , Fermentação
8.
Curr Diab Rep ; 17(5): 24, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28303386

RESUMO

PURPOSE OF REVIEW: An increasing body of evidence indicates that bio-energetic metabolism of activated T cells is a potential target to control the autoimmune response in type 1 diabetes (T1D). RECENT FINDINGS: T-cell activation and proliferation is linked to the cell capacity to provide sufficient energy and biosynthesis molecules to support T-cell growth and division. This makes T cells susceptible to metabolic inhibition for the control of the T-cell response. There is a wide therapeutic arsenal of metabolic inhibitors, including novel classes of drugs that have become recently available. With the current knowledge and availability of metabolic inhibitors, we are now in the position to design a metabolic inhibition strategy to determine whether targeting of autoreactive T cells is an effective strategy to control the process of ß-cell destruction in T1D.


Assuntos
Autoimunidade , Diabetes Mellitus Tipo 1/tratamento farmacológico , Células Secretoras de Insulina/imunologia , Linfócitos T/metabolismo , Animais , Diabetes Mellitus Tipo 1/imunologia , Humanos , Ativação Linfocitária , Redes e Vias Metabólicas , Linfócitos T/imunologia
9.
J Dairy Sci ; 100(12): 9539-9550, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28987582

RESUMO

Sweeteners and flavors are generally added to yogurt to make them more palatable. However, the addition of these ingredients may affect the fermentation process of yogurt as well as its physical and sensory characteristics. Consumers prioritize yogurt products that are "natural." A modified single-chain form of the natural sweet protein monellin extracted from the fruit of Dioscoreophyllum cumminsii, called MNEI, could be a useful alternative to artificial sweeteners. The aim of the present work was to evaluate new rapid sensory methods in combination with rheology to assess the viability of using MNEI to develop sweetened yogurts without the calories of sugar. We studied the gelation and cooling kinetics of 4 yogurt samples (unsweetened or sweetened with MNEI, aspartame, or sucrose) by using a rheometer. Furthermore, the 4 yogurts, with and without addition of a flavoring agent, were characterized from a sensory perspective using a combination of 2 rapid sensory methods, ultra flash profile and flash profile. Rheological results showed that, when added at typical usage levels, aspartame, sucrose, and MNEI did not generally affect the yogurt fermentation process or its rheological properties. Sensory results demonstrated that texture attributes of yogurts with aspartame and sucrose were strongly linked to sweetness and flavor perception, but this was not true for MNEI-sweetened yogurts. In contrast to results obtained from samples sweetened with sucrose and aspartame, MNEI protein did not sweeten the yogurt when added before fermentation. This study highlights the enhancing effect of flavor on sweetness perception, supporting previous reports that noted synergistic effects between sucrose or aspartame and flavors. Hence, future studies should be conducted to determine how sweet proteins behave in yogurt when added after fermentation.


Assuntos
Aspartame/análise , Sacarose/análise , Edulcorantes/análise , Paladar , Iogurte/análise , Adulto , Animais , Feminino , Fermentação , Frutas/química , Humanos , Masculino , Reologia
10.
Gut ; 65(1): 33-46, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25431457

RESUMO

BACKGROUND: A major cause of enteric infection, Gram-negative pathogenic bacteria activate mucosal inflammation through lipopolysaccharide (LPS) binding to intestinal toll-like receptor 4 (TLR4). Breast feeding lowers risk of disease, and human milk modulates inflammation. OBJECTIVE: This study tested whether human milk oligosaccharides (HMOSs) influence pathogenic Escherichia coli-induced interleukin (IL)-8 release by intestinal epithelial cells (IECs), identified specific proinflammatory signalling molecules modulated by HMOSs, specified the active HMOS and determined its mechanism of action. METHODS: Models of inflammation were IECs invaded by type 1 pili enterotoxigenic E. coli (ETEC) in vitro: T84 modelled mature, and H4 modelled immature IECs. LPS-induced signalling molecules co-varying with IL-8 release in the presence or absence of HMOSs were identified. Knockdown and overexpression verified signalling mediators. The oligosaccharide responsible for altered signalling was identified. RESULTS: HMOSs attenuated LPS-dependent induction of IL-8 caused by ETEC, uropathogenic E. coli, and adherent-invasive E. coli (AIEC) infection, and suppressed CD14 transcription and translation. CD14 knockdown recapitulated HMOS-induced attenuation. Overexpression of CD14 increased the inflammatory response to ETEC and sensitivity to inhibition by HMOSs. 2'-fucosyllactose (2'-FL), at milk concentrations, displayed equivalent ability as total HMOSs to suppress CD14 expression, and protected AIEC-infected mice. CONCLUSIONS: HMOSs and 2'-FL directly inhibit LPS-mediated inflammation during ETEC invasion of T84 and H4 IECs through attenuation of CD14 induction. CD14 expression mediates LPS-TLR4 stimulation of portions of the 'macrophage migration inhibitory factors' inflammatory pathway via suppressors of cytokine signalling 2/signal transducer and activator of transcription 3/NF-κB. HMOS direct inhibition of inflammation supports its functioning as an innate immune system whereby the mother protects her vulnerable neonate through her milk. 2'-FL, a principal HMOS, quenches inflammatory signalling.


Assuntos
Enterócitos/imunologia , Infecções por Escherichia coli/imunologia , Interleucina-8/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/imunologia , Leite Humano/imunologia , Trissacarídeos/imunologia , Animais , Linhagem Celular , Enterócitos/metabolismo , Escherichia coli Enterotoxigênica/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Leite Humano/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor 4 Toll-Like/metabolismo , Trissacarídeos/metabolismo
11.
J Nutr ; 146(2): 358-67, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26701795

RESUMO

BACKGROUND: The immature intestinal mucosa responds excessively to inflammatory insult, but human milk protects infants from intestinal inflammation. The ability of galactosyllactoses [galactosyloligosaccharides (GOS)], newly found in human milk oligosaccharides (HMOS), to suppress inflammation was not known. OBJECTIVE: The objective was to test whether GOS can directly attenuate inflammation and to explore the components of immune signaling modulated by GOS. METHODS: Galactosyllactose composition was measured in sequential human milk samples from days 1 through 21 of lactation and in random colostrum samples from 38 mothers. Immature [human normal fetal intestinal epithelial cell (H4)] and mature [human metastatic colonic epithelial cell (T84) and human normal colon mucosal epithelial cell (NCM-460)] enterocyte cell lines were treated with the pro-inflammatory molecules tumor necrosis factor-α (TNF-α) or interleukin-1ß (IL-1ß) or infected with Salmonella or Listeria. The inflammatory response was measured as induction of IL-8, monocyte chemoattractant protein 1 (MCP-1), or macrophage inflammatory protein-3α (MIP-3α) protein by ELISA and mRNA by quantitative reverse transcriptase-polymerase chain reaction. The ability of HMOS or synthetic GOS to attenuate this inflammation was tested in vitro and in immature human intestinal tissue ex vivo. RESULTS: The 3 galactosyllactoses (3'-GL, 4-GL, and 6'-GL) expressed in colostrum rapidly declined over early lactation (P < 0.05). In H4 cells, HMOS attenuated TNF-α- and IL-1ß-induced expression of IL-8, MIP-3α, and MCP-1 to 48-51% and pathogen-induced IL-8 and MCP-1 to 26-30% of positive controls (P < 0.001). GOS reduced TNF-α- and IL-1ß-induced inflammatory responses to 25-26% and pathogen-induced IL-8 and MCP-1 to 36-39% of positive controls (P < 0.001). GOS and HMOS mitigated nuclear translocation of nuclear transcription factor κB (NF-κB) p65. HMOS quenched the inflammatory response to Salmonella infection by immature human intestinal tissue ex vivo to 26% and by GOS to 50% of infected controls (P < 0.01). CONCLUSION: Galactosyllactose attenuated NF-κB inflammatory signaling in human intestinal epithelial cells and in human immature intestine. Thus, galactosyllactoses are strong physiologic anti-inflammatory agents in human colostrum and early milk, contributing to innate immune modulation. The potential clinical utility of galactosyllactose warrants investigation.


Assuntos
Anti-Inflamatórios/uso terapêutico , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Inflamação/prevenção & controle , Mucosa Intestinal/efeitos dos fármacos , Leite Humano/química , Oligossacarídeos/uso terapêutico , Animais , Anti-Inflamatórios/análise , Anti-Inflamatórios/farmacologia , Linhagem Celular , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Colostro/química , Feminino , Humanos , Inflamação/imunologia , Inflamação/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Lactação , Lactose/análise , Lactose/farmacologia , Lactose/uso terapêutico , Listeria , Camundongos , Oligossacarídeos/síntese química , Oligossacarídeos/farmacologia , Gravidez , Salmonella , Infecções por Salmonella/imunologia , Infecções por Salmonella/microbiologia , Infecções por Salmonella/patologia , Transdução de Sinais , Trissacarídeos/análise , Trissacarídeos/farmacologia , Trissacarídeos/uso terapêutico
12.
Angew Chem Int Ed Engl ; 55(50): 15504-15509, 2016 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-27865050

RESUMO

We demonstrate sensitive detection of alpha protons of fully protonated proteins by solid-state NMR spectroscopy with 100-111 kHz magic-angle spinning (MAS). The excellent resolution in the Cα-Hα plane is demonstrated for 5 proteins, including microcrystals, a sedimented complex, a capsid and amyloid fibrils. A set of 3D spectra based on a Cα-Hα detection block was developed and applied for the sequence-specific backbone and aliphatic side-chain resonance assignment using only 500 µg of sample. These developments accelerate structural studies of biomolecular assemblies available in submilligram quantities without the need of protein deuteration.


Assuntos
Amiloide/química , Ressonância Magnética Nuclear Biomolecular/métodos , Proteínas/química , Acinetobacter/virologia , Animais , Bacteriófagos/química , Cristalização , Humanos , Nucleocapsídeo/química , Multimerização Proteica , Prótons
13.
Microb Cell Fact ; 14: 106, 2015 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-26208726

RESUMO

BACKGROUND: Escherichia coli is, to date, the most used microorganism for the production of recombinant proteins and biotechnologically relevant metabolites. High density cell cultures allow efficient biomass and protein yields. However, their main limitation is the accumulation of acetate as a by-product of unbalanced carbon metabolism. Increased concentrations of acetate can inhibit cellular growth and recombinant protein production, and many efforts have been made to overcome this problem. On the other hand, it is known that E. coli is able to grow on acetate as the sole carbon source, although this mechanism has never been employed for the production of recombinant proteins. RESULTS: By optimization of the fermentation parameters, we have been able to develop a new acetate containing medium for the production of a recombinant protein in E. coli BL21(DE3). The medium is based on a buffering phosphate system supplemented with 0.5% yeast extract for essential nutrients and sodium acetate as additional carbon source, and it is compatible with lactose induction. We tested these culture conditions for the production of MNEI, a single chain derivative of the sweet plant protein monellin, with potential for food and beverage industries. We noticed that careful oxygenation and pH control were needed for efficient protein production. The expression method was also coupled to a faster and more efficient purification technique, which allowed us to obtain MNEI with a purity higher than 99%. CONCLUSIONS: The method introduced represents a new strategy for the production of MNEI in E. coli BL21(DE3) with a simple and convenient process, and offers a new perspective on the capabilities of this microorganism as a biotechnological tool. The conditions employed are potentially scalable to industrial processes and require only low-priced reagents, thus dramatically lowering production costs on both laboratory and industrial scale. The yield of recombinant MNEI in these conditions was the highest to date from E. coli cultures, reaching on average ~180 mg/L of culture, versus typical LB/IPTG yields of about 30 mg/L.


Assuntos
Acetatos/metabolismo , Escherichia coli/metabolismo , Proteínas de Plantas/biossíntese , Meios de Cultura/metabolismo , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Fermentação , Proteínas de Plantas/genética
14.
Cell Rep ; 43(3): 113791, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38428420

RESUMO

The "ribbon," a structural arrangement in which Golgi stacks connect to each other, is considered to be restricted to vertebrate cells. Although ribbon disruption is linked to various human pathologies, its functional role in cellular processes remains unclear. In this study, we investigate the evolutionary origin of the Golgi ribbon. We observe a ribbon-like architecture in the cells of several metazoan taxa suggesting its early emergence in animal evolution predating the appearance of vertebrates. Supported by AlphaFold2 modeling, we propose that the evolution of Golgi reassembly and stacking protein (GRASP) binding by golgin tethers may have driven the joining of Golgi stacks resulting in the ribbon-like configuration. Additionally, we find that Golgi ribbon assembly is a shared developmental feature of deuterostomes, implying a role in embryogenesis. Overall, our study points to the functional significance of the Golgi ribbon beyond vertebrates and underscores the need for further investigations to unravel its elusive biological roles.


Assuntos
Complexo de Golgi , Proteínas de Membrana , Animais , Humanos , Proteínas de Membrana/metabolismo , Complexo de Golgi/metabolismo , Citoesqueleto/metabolismo , Células HeLa , Vertebrados
15.
Environ Toxicol Chem ; 42(7): 1607-1613, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37114866

RESUMO

Over the last decade, the biological impact of microplastics in marine environments has become a serious global concern. Beyond their biological complexity, it is believed that many lethal and sublethal effects related to microplastic toxicity are triggered by oxidative stress and subsequently activated pathways. Thus, for marine organisms, having efficient mechanisms to fight the accumulation of oxidizing agents becomes indispensable to counteract the effects of microplastics. To date, our knowledge of the physiological effects of microplastics and the response of the antioxidant system in benthic species remains limited. The purpose of our study was to investigate the effects of short-term exposure on the levels of two fundamental nonprotein antioxidants, glutathione (GSH) and ovothiol (OSH), in different tissues of Mytilus galloprovincialis. Our results show that the metabolism of OSH and GSH in mussels is clearly affected by acute microplastic exposure, and that the antioxidant response differs based on sex and reproductive stage. Indeed, although in the reproductive season the overall levels of GSH and OSH in different tissues significantly increase with respect to the control condition, the antioxidant response of the organisms, especially males, in the spent stage often exhibits a biphasic U-shaped dose-response effect. Our study represents a pivotal investigation on the effects of microplastic exposure on the pools of two fundamental cellular antioxidants, with potential ecodiagnostic implications to forecast the stress status after exposure to microplastics, and highlights the possibility that the effects of these contaminants may vary over time based on the physiological condition of the animals. Environ Toxicol Chem 2023;42:1607-1613. © 2023 SETAC.


Assuntos
Mytilus , Poluentes Químicos da Água , Animais , Microplásticos/toxicidade , Microplásticos/metabolismo , Plásticos/toxicidade , Plásticos/metabolismo , Antioxidantes/metabolismo , Poluentes Químicos da Água/análise , Glutationa/metabolismo
16.
Open Biol ; 13(2): 220309, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36722300

RESUMO

Diatoms represent one of the most abundant groups of microalgae in the ocean and are responsible for approximately 20% of photosynthetically fixed CO2 on Earth. Due to their complex evolutionary history and ability to adapt to different environments, diatoms are endowed with striking molecular biodiversity and unique metabolic activities. Their high growth rate and the possibility to optimize their biomass make them very promising 'biofactories' for biotechnological applications. Among bioactive compounds, diatoms can produce ovothiols, histidine-derivatives, endowed with unique antioxidant and anti-inflammatory properties, and occurring in many marine invertebrates, bacteria and pathogenic protozoa. However, the functional role of ovothiols biosynthesis in organisms remains almost unexplored. In this work, we have characterized the thiol fraction of Phaeodactylum tricornutum, providing the first evidence of the presence of ovothiol B in pennate diatoms. We have used P. tricornutum to overexpress the 5-histidylcysteine sulfoxide synthase ovoA, the gene encoding the key enzyme involved in ovothiol biosynthesis and we have discovered that OvoA localizes in the mitochondria, a finding that uncovers new concepts in cellular redox biochemistry. We have also obtained engineered biolistic clones that can produce higher amount of ovothiol B compared to wild-type cells, suggesting a new strategy for the eco-sustainable production of these molecules.


Assuntos
Diatomáceas , Diatomáceas/genética , Engenharia Genética , Metilistidinas , Evolução Biológica
17.
Essays Biochem ; 67(4): 653-670, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37503682

RESUMO

Life sustains itself using energy generated by thermodynamic disequilibria, commonly existing as redox disequilibria. Metals are significant players in controlling redox reactions, as they are essential components of the engine that life uses to tap into the thermodynamic disequilibria necessary for metabolism. The number of proteins that evolved to catalyze redox reactions is extraordinary, as is the diversification level of metal cofactors and catalytic domain structures involved. Notwithstanding the importance of the topic, the relationship between metals and the redox reactions they are involved in has been poorly explored. This work reviews the structure and function of different prokaryotic organometallic-protein complexes, highlighting their pivotal role in controlling biogeochemistry. We focus on a specific subset of metal-containing oxidoreductases (EC1 or EC7.1), which are directly involved in biogeochemical cycles, i.e., at least one substrate or product is a small inorganic molecule that is or can be exchanged with the environment. Based on these inclusion criteria, we select and report 59 metalloenzymes, describing the organometallic structure of their active sites, the redox reactions in which they are involved, and their biogeochemical roles.


Assuntos
Metaloproteínas , Oxirredutases , Oxirredutases/química , Oxirredutases/metabolismo , Metais/química , Metais/metabolismo , Oxirredução , Metaloproteínas/química , Metaloproteínas/metabolismo , Domínio Catalítico
18.
Front Med Technol ; 4: 917151, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36134249

RESUMO

The evaluation of pharmaceutical innovation and therapeutic value is an increasingly complex exercise for which different approaches are adopted at the national level, despite the need for standardisation of processes and harmonisation of public health decisions. The objective of our analysis was to compare the approaches of the AIFA (Agenzia Italiana del Farmaco) and the HAS (Haute Autorité de Santé) in assessing the same medicinal products. In Italy, the 1525/2017 AIFA Deliberation introduces a transparent scheme for the evaluation of innovative status (innovative, conditional, not innovative) based on the therapeutic added value (TAV), therapeutic need, and quality of evidence. In contrast, in France, the HAS makes judgements using the effective clinical benefit (Service Médical Rendu) and improvement of effective clinical benefit (Amélioration du Service Médical Rendu, ASMR). This analysis focused on medicinal products evaluated both by the AIFA and by the HAS from July 2017 to September 2021. Similarities between AIFA and HAS evaluations were investigated in terms of the TAV, recognition of innovativeness, and the ASMR. Both total and partial agreements were considered relevant. Therefore, raw agreement, Cohen's kappa (weighted and unweighted), and Bangdiwala's B-statistic were estimated. A total of 102 medicinal products were included in this study. Out of these, 38 (37.2%) were orphan drugs, while 56 (54.9%) had a clinical indication for the treatment of cancer. The AIFA and HAS reached a higher level of agreement on the innovativeness status compared with the TAV. A moderate total agreement emerged in the recognition of innovativeness (k = 0.463, p-value ≤0.0001), and partial agreement was substantial (equal weight k = 0.547, squared k = 0.638), while a lack of agreement resulted in a comparison of the TAV according to the AIFA and the ASMR recognised by the HAS. Indeed, whereas the AIFA determined the TAV to be important, the HAS considered it to be moderate. In addition, whereas the AIFA identified a bias towards a moderate TAV, the HAS identified a bias towards a minor ASMR. A higher level of agreement was reached, both on the TAV and on innovative status, for less critical medical products (non-cancer-related, or non-orphan, or with a standard European Medicines Agency approval). These results underline the importance of implementing European procedures that are more broadly aligned in terms of value definition criteria.

19.
Artigo em Inglês | MEDLINE | ID: mdl-36628322

RESUMO

Haemophilia B (HB) is a rare disease which may lead to chronic disabling arthropathy, resulting in a significant clinical, social and economic impact. In recent years, new extended half-life (EHL) factor IX concentrates produced by recombinant technology (rFIX) have been developed. They have shown significantly prolonged half-life as compared to other rFIX products and improved bleeding control when used as prophylaxis. To date, EHL rFIX products reimbursed in Italy are a recombinant coagulation factor IX produced with Fc technology (rFIXFc) and a recombinant fusion protein containing rFIX fused with recombinant albumin (rIX-FP). The results of extension studies with injection intervals with a median of almost every 14 days for the complete individualized interval prophylaxis (IP) group on rFIXFc and 21 days for a selected subgroup of patients on rIX-FP have recently been published. The aim of this analysis was to estimate the cost of prophylactic treatment with rFIXFc and rIX-FP in adult patients, in the light of new clinical evidence and current average prices in Italy. The cost of therapy was estimated on the basis of the results of extension studies, the average prices reported in regional drug tenders and assuming an average patient weight of 70 kg. The analysis estimated a cost per patient/year between €224,407 and €230,355 for rFIXFc and between €242,259 and €368,587 for rIX-FP. The sensitivity analysis confirmed the robustness of the results. The use of rFIXFc over rIX-FP proves to be the least expensive choice for the treatment of HB in Italy.

20.
Sci Total Environ ; 812: 152535, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34942245

RESUMO

Diatoms are photosynthetic organisms with potential biotechnological applications in the bioremediation sector, having shown the capacity to reduce environmental concentrations of different pollutants. The diatom Cylindrotheca closterium is known to degrade di-n-butyl phthalate (DBP), one of the most abundant phthalate esters in aquatic environments and a known endocrine-disrupting chemical. In this study, we present for the first time the in silico identification of two putative DBP hydrolases (provisionally called DBPH1 and DBPH2) in the transcriptome of C. closterium. We modeled the structure of both DBPH1-2 and their proposed interactions with the substrate to gain insights into their mechanism of action. Finally, we analyzed the expression levels of the two putative hydrolases upon exposure of C. closterium to different concentrations of DBP (5 and 10 mg/l) for 24 and 48 h. The data showed a DBP concentration-dependent increase in expression levels of both dbph1 and 2 genes, further highlighting their potential involvement in phthalates degradation. This is the first identification of phthalate-degrading enzymes in microalgae, providing new insights into the possible use of diatoms in bioremediation strategies targeting phthalates.


Assuntos
Closterium , Diatomáceas , Ácidos Ftálicos , Dibutilftalato , Hidrolases/genética , Plásticos
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