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1.
Int J Mol Sci ; 23(7)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35409309

RESUMO

European black elderberry (Sambucus nigra L.) is a popular way to treat common colds or influenza infections. Mechanistically, this might be due to a direct antiviral effect or a stimulatory effect on the immune system of the host. Here, we evaluated the modulatory effects of black elderberry derived water extract (EC15) and its polysaccharide enriched fractions (CPS, BOUND, and UNBOUND) in comparison to a conventional alcoholic extract (EE25), regarding the phenotypical and functional properties of dendritic cells (DCs), which are essential cells to induce potent T cell responses. Interestingly, the water extract and its polysaccharide fractions potently induced DC maturation, while the ethanol extract did not. Moreover, the capacity to stimulate T cells by these matured DCs, as assessed using MLR assays, was statistically higher when induced by the water extracted fractions, compared to immature DCs. On the other hand, the ethanol extract EE25 did not induce T cell stimulation. Finally, the cytokine expression profiles of these DC-T cell cocultures were assessed and correlated well with increased T cell stimulation. Also, the expression of inflammatory cytokines, such as IL-6, TNF-α, and IFN-γ was highly increased in the presence of the elderberry water extract EC15, and the polysaccharide enriched CPS, BOUND, and UNBOUND fractions, but not by EE25. Thus, from these data, we conclude that the polysaccharides present in water-derived elderberry fractions induce potent immune-modulatory effects, which represents the basis for a strong immune-mediated response to viruses including influenza.


Assuntos
Influenza Humana , Sambucus nigra , Sambucus , Citocinas/metabolismo , Células Dendríticas , Etanol/farmacologia , Humanos , Imunidade , Influenza Humana/metabolismo , Extratos Vegetais , Polissacarídeos/metabolismo , Polissacarídeos/farmacologia , Linfócitos T , Água/metabolismo
2.
J Biol Chem ; 290(29): 18056-18067, 2015 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-26013828

RESUMO

Thionins are plant-specific antimicrobial peptides that have been isolated from the endosperm and leaves of cereals, from the leaves of mistletoes, and from several other plant species. They are generally basic peptides with three or four disulfide bridges and a molecular mass of ~5 kDa. Thionins are produced as preproproteins consisting of a signal peptide, the thionin domain, and an acidic domain. Previously, only mature thionin peptides have been isolated from plants, and in addition to removal of the signal peptide, at least one cleavage processing step between the thionin and the acidic domain is necessary to release the mature thionin. In this work, we identified a thionin proprotein-processing enzyme (TPPE) from barley. Purification of the enzyme was guided by an assay that used a quenched fluorogenic peptide comprising the amino acid sequence between the thionin and the acidic domain of barley leaf-specific thionin. The barley TPPE was identified as a serine protease (BAJ93208) and expressed in Escherichia coli as a strep tag-labeled protein. The barley BTH6 thionin proprotein was produced in E. coli using the vector pETtrx1a and used as a substrate. We isolated and sequenced the BTH6 thionin from barley to confirm the N and C terminus of the peptide in planta. Using an in vitro enzymatic assay, the recombinant TPPE was able to process the quenched fluorogenic peptide and to cleave the acidic domain at least at six sites releasing the mature thionin from the proprotein. Moreover, it was found that the intrinsic three-dimensional structure of the BTH6 thionin domain prevents cleavage of the mature BTH6 thionin by the TPPE.


Assuntos
Hordeum/enzimologia , Proteínas de Plantas/metabolismo , Serina Proteases/metabolismo , Tioninas/metabolismo , Sequência de Aminoácidos , Hordeum/química , Hordeum/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Conformação Proteica , Proteólise , Alinhamento de Sequência , Serina Proteases/química , Serina Proteases/isolamento & purificação , Tioninas/química
3.
Appl Environ Microbiol ; 82(24): 7185-7196, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27736791

RESUMO

The immune-modulating properties of certain bifidobacterial strains, such as Bifidobacterium longum subsp. longum 35624 (B. longum 35624), have been well described, although the strain-specific molecular characteristics associated with such immune-regulatory activity are not well defined. It has previously been demonstrated that B. longum 35624 produces a cell surface exopolysaccharide (sEPS), and in this study, we investigated the role played by this exopolysaccharide in influencing the host immune response. B. longum 35624 induced relatively low levels of cytokine secretion from human dendritic cells, whereas an isogenic exopolysaccharide-negative mutant derivative (termed sEPSneg) induced vastly more cytokines, including interleukin-17 (IL-17), and this response was reversed when exopolysaccharide production was restored in sEPSneg by genetic complementation. Administration of B. longum 35624 to mice of the T cell transfer colitis model prevented disease symptoms, whereas sEPSneg did not protect against the development of colitis, with associated enhanced recruitment of IL-17+ lymphocytes to the gut. Moreover, intranasal administration of sEPSneg also resulted in enhanced recruitment of IL-17+ lymphocytes to the murine lung. These data demonstrate that the particular exopolysaccharide produced by B. longum 35624 plays an essential role in dampening proinflammatory host responses to the strain and that loss of exopolysaccharide production results in the induction of local TH17 responses. IMPORTANCE: Particular gut commensals, such as B. longum 35624, are known to contribute positively to the development of mucosal immune cells, resulting in protection from inflammatory diseases. However, the molecular basis and mechanisms for these commensal-host interactions are poorly described. In this report, an exopolysaccharide was shown to be decisive in influencing the immune response to the bacterium. We generated an isogenic mutant unable to produce exopolysaccharide and observed that this mutation caused a dramatic change in the response of human immune cells in vitro In addition, the use of mouse models confirmed that lack of exopolysaccharide production induces inflammatory responses to the bacterium. These results implicate the surface-associated exopolysaccharide of the B. longum 35624 cell envelope in the prevention of aberrant inflammatory responses.


Assuntos
Infecções por Bifidobacteriales/imunologia , Bifidobacterium longum/imunologia , Polissacarídeos Bacterianos/imunologia , Células Th17/imunologia , Animais , Infecções por Bifidobacteriales/microbiologia , Bifidobacterium longum/genética , Citocinas/imunologia , Feminino , Humanos , Interleucina-17/imunologia , Camundongos , Camundongos Endogâmicos BALB C
4.
Plant J ; 74(5): 852-66, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23480402

RESUMO

The beet cyst nematode Heterodera schachtii induces syncytia in the roots of Arabidopsis thaliana, which are its only nutrient source. One gene, At1g64110, that is strongly up-regulated in syncytia as shown by RT-PCR, quantitative RT-PCR, in situ RT-PCR and promoter::GUS lines, encodes an AAA+-type ATPase. Expression of two related genes in syncytia, At4g28000 and At5g52882, was not detected or not different from control root segments. Using amiRNA lines and T-DNA mutants, we show that At1g64110 is important for syncytium and nematode development. At1g64110 was also inducible by wounding, jasmonic acid, salicylic acid, heat and cold, as well as drought, sodium chloride, abscisic acid and mannitol, indicating involvement of this gene in abiotic stress responses. We confirmed this using two T-DNA mutants that were more sensitive to abscisic acid and sodium chloride during seed germination and root growth. These mutants also developed significantly smaller roots in response to abscisic acid and sodium chloride. An in silico analysis showed that ATPase At1g64110 (and also At4g28000 and At5g52882) belong to the 'meiotic clade' of AAA proteins that includes proteins such as Vps4, katanin, spastin and MSP1.


Assuntos
Adenosina Trifosfatases/genética , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Ácido Abscísico/farmacologia , Animais , Arabidopsis/citologia , Arabidopsis/parasitologia , Ciclopentanos/farmacologia , Secas , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Células Gigantes/parasitologia , Interações Hospedeiro-Parasita , Manitol/farmacologia , Mutação , Oxilipinas/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/parasitologia , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ácido Salicílico/farmacologia , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/parasitologia , Cloreto de Sódio/farmacologia , Estresse Mecânico , Temperatura , Tylenchoidea/fisiologia
5.
Protein Expr Purif ; 101: 76-83, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24927642

RESUMO

The barley protease BAJ93208 belongs to the subtilase family of serine proteases. We have expressed BAJ93208 in the cytoplasm of the Escherichiacoli strain SHuffle C3030 using a rhamnose-inducible promoter. The expression construct included a (His)6-tag at the N-terminus and a strep-tag at the C-terminus. Western blot analysis revealed that the protein was processed at the N- and C-terminus. To exclude that this processing was due to contaminating E. coli proteases, a mutated BAJ93208 protease was constructed. This inactive mutant was not processed, demonstrating that the processing was an autocatalytic process. To define the exact cleavage sites mass spectrometry was used which detected four differently processed versions of the protease. At the N-terminus, the self-processing removed the internal inhibitor and an additional 19 amino acids. At the C-terminus there was a cleavage site after Ala(765) which also removed the strep-tag. This explained the inability to detect the purified (His)6-BAJ93208-strep protease with an anti-strep-tag antibody. Finally, an additional alanine was removed either at the N-terminus (Ala(119)) or at the C-terminus (Ala(764)).


Assuntos
Escherichia coli/metabolismo , Hordeum/enzimologia , Proteínas Recombinantes/genética , Subtilisinas/genética , Sequência de Aminoácidos , Substituição de Aminoácidos , Clonagem Molecular , Escherichia coli/genética , Etiquetas de Sequências Expressas , Expressão Gênica , Espectrometria de Massas , Dados de Sequência Molecular , Mutação , Regiões Promotoras Genéticas , Proteínas Recombinantes/metabolismo , Subtilisinas/biossíntese , Subtilisinas/metabolismo
6.
Nutrients ; 16(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38613057

RESUMO

Evidence suggests that tart cherry (TC) supplementation has beneficial effects on health indices and recovery following strenuous exercise. However, little is known about the mechanisms and how TC might modulate the human metabolome. The aim of this study was to evaluate the influence of an acute high- and low-dose of Vistula TC supplementation on the metabolomic profile in humans. In a randomised, double-blind, placebo controlled, cross-over design, 12 healthy participants (nine male and three female; mean ± SD age, stature, and mass were 29 ± 7 years old, 1.75 ± 0.1 m, and 77.3 ± 10.5 kg, respectively) visited the laboratory on three separate occasions (high dose; HI, low dose; LO, or placebo), separated by at least seven days. After an overnight fast, a baseline venous blood sample was taken, followed by consumption of a standardised breakfast and dose conditions (HI, LO, or placebo). Subsequent blood draws were taken 1, 2, 3, 5, and 8 h post consumption. Following sample preparation, an untargeted metabolomics approach was adopted, and the extracts analysed by LCMS/MS. When all time points were collated, a principal component analysis showed a significant difference between the conditions (p < 0.05), such that the placebo trial had homogeneity, and HI showed greater heterogeneity. In a sub-group analysis, cyanidine-3-O-glucoside (C3G), cyanidine-3-O-rutinoside (C3R), and vanillic acid (VA) were detected in plasma and showed significant differences (p < 0.05) following acute consumption of Vistula TC, compared to the placebo group. These results provide evidence that phenolics are bioavailable in plasma and induce shifts in the metabolome following acute Vistula TC consumption. These data could be used to inform future intervention studies where changes in physiological outcomes could be influenced by metabolomic shifts following acute supplementation.


Assuntos
Prunus avium , Humanos , Feminino , Masculino , Adulto Jovem , Adulto , Metaboloma , Metabolômica , Estatura , Desjejum
7.
Biotechnol Lett ; 35(7): 1085-91, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23515894

RESUMO

Thionins are antimicrobial plant peptides produced as preproproteins consisting of a signal peptide, the thionin domain, and a so-called acidic domain. Only thionin itself has been isolated from plants. To study the processing of the precursor, it has to be produced in a heterologous system. Since both domains contain several cysteines and, due to the known antimicrobial activity of the thionin, we tested the expression of all four Arabidopsis proproteins as fusion proteins. Periplasmic expression as fusion with maltose binding protein was not successful but cytoplasmic expression as His-tagged TRX fusion proteins with a TEV recognition sequence resulted in proteins of correct size. Use of the SHuffle strain C3030 further improved the expression. Fusion proteins inhibited growth of Escherichia coli. They could be cleaved by TEV protease, releasing authentic proproteins without any additional amino acid at the N-terminus.


Assuntos
Proteínas de Arabidopsis/biossíntese , Escherichia coli/metabolismo , Precursores de Proteínas/biossíntese , Tioninas/biossíntese , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Citoplasma/metabolismo , Escherichia coli/genética , Engenharia Genética/métodos , Periplasma/metabolismo , Precursores de Proteínas/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Tioninas/genética
8.
J Pers Med ; 12(9)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36143265

RESUMO

(1) Background: The intestinal microbiome has emerged as a central factor in human physiology and its alteration has been associated with disease. Therefore, great hopes are placed in microbiota-modulating strategies. Among various approaches, prebiotics, substrates with selective metabolization conferring a health benefit to the host, are promising candidates. Herein, we studied the prebiotic properties of a purified extract from European black elderberries, with a high and standardized content of polyphenols and anthocyanins. (2) Methods: The ELDERGUT trial represents a 9-week longitudinal intervention study divided into 3 distinct phases, namely a baseline, an intervention and a washout period, three weeks each. The intervention consisted of capsules containing 300 mg elderberry extract taken twice a day. Patient-reported outcomes and biosamples were collected weekly. Microbiome composition was assessed using 16S amplicon metagenomics. (3) Results: The supplementation was well tolerated. Microbiome trajectories were highly individualized with a profound shift in diversity indices immediately upon initiation and after termination of the compound. This was accompanied by corresponding changes in species abundance over time. Of particular interest, the relative abundance of Akkermansia spp. continued to increase in a subset of participants even beyond the supplementation period. Associations with participant metadata were detected.

9.
PLoS One ; 11(9): e0162983, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27656878

RESUMO

The Bifibobacterium longum subsp. longum 35624™ strain (formerly named Bifidobacterium longum subsp. infantis) is a well described probiotic with clinical efficacy in Irritable Bowel Syndrome clinical trials and induces immunoregulatory effects in mice and in humans. This paper presents (a) the genome sequence of the organism allowing the assignment to its correct subspeciation longum; (b) a comparative genome assessment with other B. longum strains and (c) the molecular structure of the 35624 exopolysaccharide (EPS624). Comparative genome analysis of the 35624 strain with other B. longum strains determined that the sub-speciation of the strain is longum and revealed the presence of a 35624-specific gene cluster, predicted to encode the biosynthetic machinery for EPS624. Following isolation and acid treatment of the EPS, its chemical structure was determined using gas and liquid chromatography for sugar constituent and linkage analysis, electrospray and matrix assisted laser desorption ionization mass spectrometry for sequencing and NMR. The EPS consists of a branched hexasaccharide repeating unit containing two galactose and two glucose moieties, galacturonic acid and the unusual sugar 6-deoxy-L-talose. These data demonstrate that the B. longum 35624 strain has specific genetic features, one of which leads to the generation of a characteristic exopolysaccharide.

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