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1.
Int J Biol Macromol ; 273(Pt 1): 132968, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38871097

RESUMEN

Eukaryotic Initiation Translation Factor 2A (EIF2A) is considered to be primarily responsible for the initiation of translation when a cell is subjected to stressful conditions. However, information regarding this protein is still incomplete. Using a combination of proteomic approaches, we demonstrated that EIF2A is the molecular target of the naturally occurring bioactive compound cannabidiolic acid (CBDA) within human glioblastoma cells. This finding allowed us to undertake a study aimed at obtaining further information on the functions that EIF2A plays in tumor cells. Indeed, our data showed that CBDA is able to activate EIF2A when the cells are in no-stress conditions. It induces conformational changes in the protein structure, thus increasing EIF2A affinity towards the proteins participating in the Eukaryotic Translation Machinery. Consequently, following glioblastoma cells incubation with CBDA we observed an enhanced neosynthesis of proteins involved in the stress response, nucleic acid translation and organization, and protein catabolism. These changes in gene expression resulted in increased levels of ubiquitinated proteins and accumulation of the autophagosome. Our results, in addition to shedding light on the molecular mechanism underlying the biological effect of a phytocannabinoid in cancer cells, demonstrated that EIF2A plays a critical role in regulation of protein homeostasis.


Asunto(s)
Factor 2 Eucariótico de Iniciación , Glioblastoma , Humanos , Glioblastoma/metabolismo , Glioblastoma/patología , Factor 2 Eucariótico de Iniciación/metabolismo , Línea Celular Tumoral , Proteostasis/efectos de los fármacos , Biosíntesis de Proteínas/efectos de los fármacos , Proteómica/métodos
2.
Cancers (Basel) ; 15(23)2023 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-38067286

RESUMEN

Cervical cancer ranks as the fourth most prevalent cancer among women globally, with approximately 600,000 new cases being diagnosed each year. The principal driver of cervical cancer is the human papillomavirus (HPV), where viral oncoproteins E6 and E7 undertake the role of driving its carcinogenic potential. Despite extensive investigative efforts, numerous facets concerning HPV infection, replication, and pathogenesis remain shrouded in uncertainty. The virus operates through a variety of epigenetic mechanisms, and the epigenetic signature of HPV-related tumors is a major bottleneck in our understanding of the disease. Recent investigations have unveiled the capacity of viral oncoproteins to influence epigenetic changes within HPV-related tumors, and conversely, these tumors exert an influence on the surrounding epigenetic landscape. Given the escalating occurrence of HPV-triggered tumors and the deficiency of efficacious treatments, substantial challenges emerge. A promising avenue to address this challenge lies in epigenetic modulators. This review aggregates and dissects potential epigenetic modulators capable of combatting HPV-associated infections and diseases. By delving into these modulators, novel avenues for therapeutic interventions against HPV-linked cancers have come to the fore.

3.
Pharmaceutics ; 15(8)2023 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-37631302

RESUMEN

Pain is an unpleasant sensory and emotional experience that affects every aspect of a patient's life and which may be treated through different pharmacological and non-pharmacological approaches. Analgesics are the drugs most commonly used to treat pain, and in specific situations, the use of opioids may be considered with caution. These drugs, in fact, do not always induce optimal analgesia in patients, and several problems are associated with their use. The purpose of this narrative review is to describe the pharmacological approaches currently used for the management of chronic pain. We review several aspects, from the pain-scale-based methods currently available to assess the type and intensity of pain, to the most frequently administered drugs (non-narcotic analgesics and narcotic analgesics), whose pharmacological characteristics are briefly reported. Overall, we attempt to provide an overview of different pharmacological treatments while also illustrating the relevant guidelines and indications. We then report the strategies that may be used to reduce problems related to opioid use. Specifically, we focus our attention on therapeutic drug monitoring (TDM), a tool that could help clinicians select the most suitable drug and dose to be used for each patient. The actual potential of using TDM to optimize and personalize opioid-based pain treatments is finally discussed based on recent scientific reports.

4.
Antioxidants (Basel) ; 12(7)2023 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-37507941

RESUMEN

Plants of genus Cichorium (Asteraceae) can be used as vegetables with higher nutritional value and as medicinal plants. This genus has beneficial properties owing to the presence of a number of specialized metabolites such as alkaloids, sesquiterpene lactones, coumarins, unsaturated fatty acids, flavonoids, saponins, and tannins. Cichorium endivia L., known as escarole, has achieved a common food status due to its nutritionary value, bitter taste, and the presence of healthy components, and is eaten cooked or raw in salads. Presently, wastes derived from the horticultural crops supply chain are generated in very large amounts. Vegetable waste comprises the discarded leaves of food sources produced during collection, handling, transportation, and processing. The external leaves of Cichorium endivia L. are a horticultural crop that is discarded. In this work, the phytochemical profile, antioxidant, and anti-inflammatory activities of hydroalcoholic extract obtained from discarded leaves of three cultivars of escarole (C. endivia var. crispum 'Capriccio', C. endivia var. latifolium 'Performance' and 'Leonida') typical horticultural crop of the Campania region were investigated. In order to describe a metabolite profile of C. endivia cultivars, the extracts were analysed by HR/ESI/Qexactive/MS/MS and NMR. The careful analysis of the accurate masses, the ESI/MS spectra, and the 1H NMR chemical shifts allowed for the identification of small molecules belonging to phenolic, flavonoid, sesquiterpene, amino acids, and unsaturated fatty acid classes. In addition, the antioxidant potential of the extracts was evaluated using cell-free and cell-based assays, as well as their cytotoxic and anti-inflammatory activity. All the extracts showed similar radical-scavenging ability while significant differences between the three investigated cultivars emerged in the cell-based assays. The obtained data were ascribed to the content of polyphenols and sesquiterpenes in the extracts. Accordingly, C. endivia by-products can be deemed an interesting material for healthy product formulations.

5.
J Pharm Biomed Anal ; 232: 115416, 2023 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-37120973

RESUMEN

A tight adherence to a gluten-free diet (GFD), the most effective treatment currently available for celiac disease, is important to reduce symptoms, avoid nutritional deficiencies and improve quality of life in celiac patients. The development of analytical methods allowing detecting gluten exposure due to occasional or involuntary food transgressions could represent a useful tool to monitor patient habits and conditions and prevent long-term complications. The aim of this work was to develop and validate an approach based on the standard addition methodology (SAM) for the detection and quantification of two main metabolites of alkylresorcinols, 3,5-dihydroxybenzoic acid (DHBA) and 3-(3,5-dihydroxyphenyl)-propanoic acid (DHPPA), whose presence in urine samples is related to the intake of gluten-containing foods. Analytically, the method consisted of a protein precipitation step followed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) analysis. The chromatographic method involved the use of a hydrophilic interaction liquid chromatography (HILIC) in a direct phase approach; LC-MS/MS analyses were performed in selected reaction monitoring (SRM) mode. Manipulation and instrumental errors were normalised using stable isotopic standards (ISs). The SAM approach here described requires less than 1 mL of urine per sample, thus greatly reducing the sample volume needed. Noteworthy, despite the small cohort of samples analysed, our data allowed to identify a potential "threshold" value, around 200 ng/mL for DHBA and 400 ng/mL for DHPPA, to discriminate between a GFD and a gluten rich diet (GRD).


Asunto(s)
Glútenes , Espectrometría de Masas en Tándem , Humanos , Cromatografía Liquida , Calidad de Vida , Dieta Sin Gluten
6.
Nat Commun ; 14(1): 2233, 2023 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-37076525

RESUMEN

Bacterial cell growth and division require the coordinated action of enzymes that synthesize and degrade cell wall polymers. Here, we identify enzymes that cleave the D-arabinan core of arabinogalactan, an unusual component of the cell wall of Mycobacterium tuberculosis and other mycobacteria. We screened 14 human gut-derived Bacteroidetes for arabinogalactan-degrading activities and identified four families of glycoside hydrolases with activity against the D-arabinan or D-galactan components of arabinogalactan. Using one of these isolates with exo-D-galactofuranosidase activity, we generated enriched D-arabinan and used it to identify a strain of Dysgonomonas gadei as a D-arabinan degrader. This enabled the discovery of endo- and exo-acting enzymes that cleave D-arabinan, including members of the DUF2961 family (GH172) and a family of glycoside hydrolases (DUF4185/GH183) that display endo-D-arabinofuranase activity and are conserved in mycobacteria and other microbes. Mycobacterial genomes encode two conserved endo-D-arabinanases with different preferences for the D-arabinan-containing cell wall components arabinogalactan and lipoarabinomannan, suggesting they are important for cell wall modification and/or degradation. The discovery of these enzymes will support future studies into the structure and function of the mycobacterial cell wall.


Asunto(s)
Mycobacterium tuberculosis , Polisacáridos , Humanos , Polisacáridos/metabolismo , Mycobacterium tuberculosis/metabolismo , Glicósido Hidrolasas/metabolismo , Pared Celular/metabolismo
7.
Sci Rep ; 13(1): 1835, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36725873

RESUMEN

Livestock breeding activities and pharmaceutical wastes lead to considerable accumulation of steroid hormones and estrogens in wastewaters. Here estrogens act as pro-cancerogenic agents and endocrine disruptors interfering with the sexual development of aquatic animals and having toxic effects in humans. Environmental bacteria play a vital role in estrogens degradation. Their wide reservoir of enzymes, such as ring cleavage dioxygenases (RCDs), can degrade the steroid nucleus, catalyzing the meta-cleavage of A, B or D steroid rings. In this work, 4 extra-diol ring cleavage dioxygenases (ERCDs), PP28735, PP26077, PP00124 and PP00193, were isolated from the marine sphingomonad Novosphingobium sp. PP1Y and characterized. Enzymes kinetic parameters were determined on different synthetic catecholic substrates. Then, the bioconversion of catechol estrogens was evaluated. PP00124 showed to be an efficient catalyst for the degradation of 4-hydroxyestradiol (4-OHE2), a carcinogenic hydroxylated derivate of E2. 4-OHE2 complete cleavage was obtained using PP00124 both in soluble form and in whole recombinant E. coli cells. LC-MS/MS analyses confirmed the generation of a semialdehyde product, through A-ring meta cleavage. To the best of our knowledge, PP00124 is the first characterized enzyme able to directly degrade 4-OHE2 via meta cleavage. Moreover, the complete 4-OHE2 biodegradation using recombinant whole cells highlighted advantages for bioremediation purposes.


Asunto(s)
Biodegradación Ambiental , Dioxigenasas , Estrógenos , Sphingomonadaceae , Humanos , Cromatografía Liquida , Dioxigenasas/genética , Dioxigenasas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Estrógenos/metabolismo , Estrógenos de Catecol , Sphingomonadaceae/genética , Sphingomonadaceae/metabolismo , Espectrometría de Masas en Tándem
8.
Antioxidants (Basel) ; 11(11)2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36421448

RESUMEN

A comparative quali-quantitative study of the peel extracts of eight Punica granatum cultivars obtained from underexploited areas of South Italy was carried out in order to valorize them as health-promoting by-products. The results showed that all of the samples possessed 45 ellagitannins, consisting mainly of polyhydroxyphenoyls; 10 flavonoids, belonging to flavonol, flavone, and catechin classes; and 2 anthocyanins. The most representative compounds underwent quantification through a LC-MS/MS multiple reaction monitoring (MRM)-based method; their qualitative profile was almost superimposable, while variability in the quantitative phenolic content was observed. The antioxidant activity was investigated using cell-free and cell-based assays. The in vitro anti-inflammatory potential was also studied by monitoring three typical markers of inflammation (IL-1ß, IL-6, and TNF-α). Moderate differences in both activities were observed between the cultivars. Results showed that all of the investigated peels have a potential use as healthy bioactive phytocomplexes due to the interesting antioxidant and anti-inflammatory activities; in particular from the bioinformatic approaches a series of compounds, including galloyl-, pedunculagin- and ellagic acid-based, were found to be highly correlated with bioactivity of the extracts. Finally, the bioactivities showed by a Campanian local cultivar, 'Granato di Aiello del Sabato', could promote its cultivation by local farmers and germplasm conservation.

9.
Biotechnol Lett ; 44(11): 1313-1322, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36161539

RESUMEN

OBJECTIVES: The aim of the present work was to identify a time-saving, effective, and low-cost strategy to produce in Escherichia coli a protein chimera representing a fusion anti-SARS-CoV-2 candidate vaccine, consisting of immunogenic and antigenic moieties. RESULTS: We overexpressed in E. coli BL21(DE3) a synthetic gene coding for CRM197-RBD, and the target protein was detected in inclusion bodies. CRM197-RBD was solubilized with 1 % (w/v) of the anionic detergent N-lauroylsarcosine (sarkosyl), the removal of which from the protein solution was conveniently accomplished with Amberlite XAD-4. The detergent-free CRM197-RBD was then separated from contaminating DNA using polyethylenimine (PEI), and finally purified from PEI by salting out with ammonium sulfate. Structural (CD spectrum) and functional (DNase activity) assays revealed that the CRM197-RBD chimera featured a native and active conformation. Remarkably, we determined a yield of purified CRM197-RBD equal to 23 mg per litre of culture. CONCLUSIONS: To produce CRM197-RBD, we devised the use of sarkosyl as an alternative to urea to solubilize the target protein from E. coli inclusion bodies, and the easy removal of sarkosyl by means of Amberlite XAD-4.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Humanos , COVID-19/prevención & control , Vacunas contra la COVID-19/biosíntesis , Escherichia coli , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo
10.
J Nat Prod ; 85(7): 1667-1680, 2022 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-35748331

RESUMEN

Sixteen diterpenes (1-16), along with 10 previously described compounds, including four flavonoids and six diterpenes, were isolated from the aerial parts of Psiadia punctulata growing in Saudi Arabia. The diterpene structures were elucidated using NMR spectroscopy and mass spectrometry data. Furthermore, a DFT/NMR procedure was used to suggest the relative configuration of several compounds. The labdane-derived skeletons, namely, ent-atisane, ent-beyerene, ent-trachylobane, and ent-kaurene, were identified. The extracts, fractions, and pure compounds were then tested against Staphylococcus aureus, Streptococcus mutans, Treponema denticola, and Lactobacillus plantarum. One diterpenoid, namely, psiadin, showed an additive effect with the antiseptic chlorhexidine, with a fractional inhibitory concentration index of less than 1. Additionally, psiadin showed a prospective inhibition activity for bacterial efflux pumps.


Asunto(s)
Antiinfecciosos , Asteraceae , Diterpenos , Asteraceae/química , Diterpenos/química , Estructura Molecular , Estudios Prospectivos
11.
Nutrients ; 14(10)2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35631233

RESUMEN

Exercise training (ET) is a natural activator of silent mating type information regulation 2 homolog 1 (SIRT1), a stress-sensor able to increase the endogenous antioxidant system. SIRT1 activators include polyphenols and vitamins, the antioxidant properties of which are well-known. Antioxidant supplements are used to improve athletic performance. However, they might blunt ET-related benefits. Middle-distance runners (MDR) taking (MDR-S) or not taking antioxidant supplements (MDR-NoS) were compared with each other and with sedentary subjects (CTR) to evaluate the ET effects on SIRT1 levels and oxidative stress, and to investigate whether an exogenous source of antioxidants could interfere with such effects. Thirty-two MDR and 14 CTR were enrolled. MDR-S took 240 mg vitamin C and 15 mg vitamin E together with mineral salts. SIRT1 mRNA and activity were measured in PBMCs. Total oxidative status (TOS) and total antioxidant capacity (TEAC) were determined in plasma. MDR showed higher levels of SIRT1 mRNA (p = 0.0387) and activity (p = 0.0055) than did CTR. MDR-NoS also showed higher levels than did MDR-S without reaching statistical significance. SIRT1 activity was higher (p = 0.0012) in MDR-NoS (1909 ± 626) than in MDR-S (1276 ± 474). TOS did not differ among the groups, while MDR showed higher TEAC levels than did CTR (2866 ± 581 vs. 2082 ± 560, p = 0.0001) as did MDR-S (2784 ± 643) and MDR-NoS (2919 ± 551) (MDR-S vs. CTR, p = 0.0007 and MDR-NoS vs. CTR, p = 0.003). TEAC (ß = 0.4488356, 95% CI 0.2074645 0.6902067; p < 0.0001) and the MDR-NoS group (ß = 744.6433, 95% CI 169.9954 1319.291; p= 0.012) predicted SIRT1 activity levels. Antioxidant supplementation seems to hinder the role of ET as a natural activator of SIRT1.


Asunto(s)
Antioxidantes , Sirtuina 1 , Antioxidantes/farmacología , Suplementos Dietéticos , Ejercicio Físico/fisiología , Humanos , ARN Mensajero , Sirtuina 1/genética
12.
J Pharm Biomed Anal ; 204: 114252, 2021 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-34265485

RESUMEN

Therapeutic drug monitoring (TDM) is a recognized method to improve the quality of use of antiepileptic drugs, such as perampanel (PRP). It is the first compound in the class of selective non-competitive antagonists of AMPA receptors approved in 2012 in Europe and United States for adjunctive therapy of partial seizures. Although several studies have recently underlined that a general reference range for PRP plasmatic concentration might be difficult to propose, TDM of this drug is important in specific clinical situations, as hepatic or renal impairment or co-administration with enzyme-inducing antiepileptics. Several methods have been described in literature for the determination of PRP in different biological matrices, which include the use of liquid chromatography methods coupled with ultraviolet, fluorescence, mass or tandem-mass spectrometry detection. Here we describe the development and validation of a novel method for the measurement of PRP in plasma samples, based on a HPLC-UV/FL double detection approach and using ketoprofen as internal standard. PRP concentration in a small subset of plasma samples of treated patients was evaluated using both our approach and a commercially available CE-IVD LC-MS/MS method. The results obtained were compared, and confirmed the possibility to use our method as an alternative to LC-MS/MS in clinical routine.


Asunto(s)
Preparaciones Farmacéuticas , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Monitoreo de Drogas , Humanos , Nitrilos , Piridonas , Reproducibilidad de los Resultados
13.
Pharmaceutics ; 13(5)2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-34062983

RESUMEN

Flavonoids are among the most abundant natural bioactive compounds produced by plants. Many different activities have been reported for these secondary metabolites against numerous cells and systems. One of the most interesting is certainly the antimicrobial, which is stimulated through various molecular mechanisms. In fact, flavonoids are effective both in directly damaging the envelope of Gram-negative and Gram-positive bacteria but also by acting toward specific molecular targets essential for the survival of these microorganisms. The purpose of this paper is to present an overview of the most interesting results obtained in the research focused on the study of the interactions between flavonoids and bacterial proteins. Despite the great structural heterogeneity of these plant metabolites, it is interesting to observe that many flavonoids affect the same cellular pathways. Furthermore, it is evident that some of these compounds interact with more than one target, producing multiple effects. Taken together, the reported data demonstrate the great potential of flavonoids in developing innovative systems, which can help address the increasingly serious problem of antibiotic resistance.

14.
Int J Mol Sci ; 21(9)2020 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-32375354

RESUMEN

Aptamers or chemical antibodies are single-stranded DNA or RNA oligonucleotides that bind proteins and small molecules with high affinity and specificity by recognizing tertiary or quaternary structures as antibodies. Aptamers can be easily produced in vitro through a process known as systemic evolution of ligands by exponential enrichment (SELEX) or a cell-based SELEX procedure. Aptamers and modified aptamers, such as slow, off-rate, modified aptamers (SOMAmers), can bind to target molecules with less polar and more hydrophobic interactions showing slower dissociation rates, higher stability, and resistance to nuclease degradation. Aptamers and SOMAmers are largely employed for multiplex high-throughput proteomics analysis with high reproducibility and reliability, for tumor cell detection by flow cytometry or microscopy for research and clinical purposes. In addition, aptamers are increasingly used for novel drug delivery systems specifically targeting tumor cells, and as new anticancer molecules. In this review, we summarize current preclinical and clinical applications of aptamers in malignant and non-malignant hematological diseases.


Asunto(s)
Aptámeros de Nucleótidos , Terapia Genética , Enfermedades Hematológicas/diagnóstico , Enfermedades Hematológicas/terapia , Técnicas de Diagnóstico Molecular , Oligonucleótidos Antisentido , Animales , Ensayos Clínicos como Asunto , Manejo de la Enfermedad , Evaluación Preclínica de Medicamentos , Terapia Genética/métodos , Enfermedades Hematológicas/etiología , Enfermedades Hematológicas/mortalidad , Humanos , Técnica SELEX de Producción de Aptámeros , Resultado del Tratamiento
15.
Arch Biochem Biophys ; 679: 108189, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31726038

RESUMEN

Flavonoid natural products are well known for their beneficial antimicrobial, antitumor, and anti-inflammatory properties, however, some of these natural products often are rhamnosylated, which severely limits their bioavailability. The lack of endogenous rhamnosidases in the human GI tract not only prevents many of these glycosylated compounds from being of value in functional foods but also limits the modification of natural product libraries being tested for drug discovery. RHA-P is a catalytically efficient, thermostable α-l-rhamnosidase from the marine bacterium Novosphingobium sp. PP1Y that selectively hydrolyzes α-1,6 and α-1,2 glycosidic linkages between a terminal rhamnose and a flavonoid moiety. This work reports the 2.2 Šresolution crystal structure of RHA-P, which is an essential step forward in the characterization of RHA-P as a potential catalyst to increase the bioavailability of rhamnosylated natural compounds. The structure shows highly conserved rhamnose- and calcium-binding residues in a shallow active site that is housed in the (ß/α)8 domain. In comparison to BT0986 (pdbID: 5MQN), the only known structure of an RHA-P homolog, the morphology, electrostatic potentials and amino acid composition of the substrate binding pocket are significantly different, offering insight into the substrate preference of RHA-P for glycosylated aryl compounds such as hesperidin, naringin, rutin, and quercitrin, over polysaccharides, which are preferred by BT0986. These preferences were further explored by using in silico docking, the results of which are consistent with the known kinetic data for RHA-P acting on different rhamnosylated flavonoids. Due to its promiscuity, relative thermostability compared to other known rhamnosidases, and catalytic efficiency even in significant concentrations of organic solvents, RHA-P continues to show potential for biocatalytic applications.


Asunto(s)
Glicósido Hidrolasas/química , Glicósido Hidrolasas/metabolismo , Sphingomonadaceae/enzimología , Cristalografía por Rayos X , Dominios Proteicos , Electricidad Estática , Especificidad por Sustrato
16.
J Microbiol ; 57(6): 498-508, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31054137

RESUMEN

Outer membrane vesicles (OMVs) are nanostructures of 20-200 nm diameter deriving from the surface of several Gram-negative bacteria. OMVs are emerging as shuttles involved in several mechanisms of communication and environmental adaptation. In this work, OMVs were isolated and characterized from Novosphingobium sp. PP1Y, a Gram-negative non-pathogenic microorganism lacking LPS on the outer membrane surface and whose genome was sequenced and annotated. Scanning electron microscopy performed on samples obtained from a culture in minimal medium highlighted the presence of PP1Y cells embedded in an extracellular matrix rich in vesicular structures. OMVs were collected from the exhausted growth medium during the mid-exponential phase, and purified by ultracentrifugation on a sucrose gradient. Atomic force microscopy, dynamic light scattering and nanoparticle tracking analysis showed that purified PP1Y OMVs had a spherical morphology with a diameter of ca. 150 nm and were homogenous in size and shape. Moreover, proteomic and fatty acid analysis of purified OMVs revealed a specific biochemical "fingerprint", suggesting interesting details concerning their biogenesis and physiological role. Moreover, these extracellular nanostructures do not appear to be cytotoxic on HaCaT cell line, thus paving the way to their future use as novel drug delivery systems.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/metabolismo , Membrana Celular/metabolismo , Vesículas Secretoras/química , Vesículas Secretoras/enzimología , Sphingomonadaceae/metabolismo , Proteínas de la Membrana Bacteriana Externa/aislamiento & purificación , Línea Celular , Supervivencia Celular/efectos de los fármacos , Exocitosis , Ácidos Grasos/análisis , Humanos , Queratinocitos/efectos de los fármacos , Microscopía Electrónica de Rastreo , Nanopartículas , Péptido Hidrolasas/metabolismo , Proteómica/métodos , Sphingomonadaceae/citología
17.
Biotechnol Lett ; 41(2): 273-281, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30542947

RESUMEN

OBJECTIVE: The antioxidant activity and protective effect of a methanolic extract obtained from the marine Gram-negative bacterium Novosphingobium sp. PP1Y, isolated from the surface water of a polluted area in the harbour of Pozzuoli (Naples, Italy), was evaluated. RESULTS: The extract was tested in vitro on epithelial colorectal adenocarcinoma cells and in vivo on Caenorhabditis elegans. It showed strong protective activity against oxidative stress, in both experimental systems, by preventing ROS accumulation. In the case of the cells, pre-treatment with methanolic extract was also able to maintain unaltered intracellular GSH levels and phosphorylation levels of mitogen-activated protein kinases p38. Instead, in the case of the worms, the extract was able to modulate the expression levels of stress response genes, by activating the transcription factor skn-1. CONCLUSIONS: From a biotechnological and economical point of view, antioxidants from microorganisms are convenient as they provide a valid alternative to chemical synthesis and respond to the ever-growing market demand for natural antioxidants.


Asunto(s)
Antioxidantes/aislamiento & purificación , Caenorhabditis elegans/metabolismo , Neoplasias Colorrectales/metabolismo , Metanol/aislamiento & purificación , Sphingomonadaceae/metabolismo , Animales , Antioxidantes/farmacología , Caenorhabditis elegans/efectos de los fármacos , Línea Celular Tumoral , Neoplasias Colorrectales/tratamiento farmacológico , Regulación de la Expresión Génica/efectos de los fármacos , Glutatión/metabolismo , Humanos , Metabolómica/métodos , Metanol/farmacología , Estrés Oxidativo/efectos de los fármacos , Fosforilación , Sphingomonadaceae/aislamiento & purificación , Factores de Transcripción/genética , Microbiología del Agua , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
18.
Arch Biochem Biophys ; 648: 1-11, 2018 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-29678627

RESUMEN

α-L-Rhamnosidases (α-RHAs, EC 3.2.1.40) are glycosyl hydrolases (GHs) hydrolyzing terminal α-l-rhamnose residues from different substrates such as heteropolysaccharides, glycosylated proteins and natural flavonoids. Although the possibility to hydrolyze rhamnose from natural flavonoids has boosted the use of these enzymes in several biotechnological applications over the past decades, to date only few bacterial rhamnosidases have been fully characterized and only one crystal structure of a rhamnosidase of the GH106 family has been described. In our previous work, an α-l-rhamnosidase belonging to this family, named RHA-P, was isolated from the marine microorganism Novosphingobium sp. PP1Y. The initial biochemical characterization highlighted the biotechnological potential of RHA-P for bioconversion applications. In this work, further functional and structural characterization of the enzyme is provided. The recombinant protein was obtained fused to a C-terminal His-tag and, starting from the periplasmic fractions of induced recombinant cells of E. coli strain BL21(DE3), was purified through a single step purification protocol. Homology modeling of RHA-P in combination with a site directed mutagenesis analysis confirmed the function of residues D503, E506, E644, likely located at the catalytic site of RHA-P. In addition, a kinetic characterization of the enzyme on natural flavonoids such as naringin, rutin, hesperidin and quercitrin was performed. RHA-P showed activity on all flavonoids tested, with a catalytic efficiency comparable or even higher than other bacterial α-RHAs described in literature. The results confirm that RHA-P is able to hydrolyze both α-1,2 and α-1,6 glycosidic linkages, and suggest that the enzyme may locate different polyphenolic aromatic moities in the active site.


Asunto(s)
Glicósido Hidrolasas/química , Glicósido Hidrolasas/metabolismo , Sphingomonadaceae/enzimología , Calcio/metabolismo , Regulación Bacteriana de la Expresión Génica , Glicósido Hidrolasas/genética , Hidrólisis , Modelos Moleculares , Conformación Proteica , Especificidad por Sustrato
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