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1.
Arch Microbiol ; 206(11): 424, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39361031

RESUMO

Inulin, a widely recognized prebiotic, has diverse applications across various industrial sectors. Although inulin is primarily produced through plant extraction, there is growing interest in enzymatic synthesis as an alternative. The enzymatic production of inulin from sucrose, which yields polymers with degrees of polymerization similar to those of plant-derived inulin, shows potential as a viable replacement for traditional extraction methods. In this study, an inulosucrase from Neobacillus bataviensis was identified, demonstrating a non-processive mechanism specifically tailored for synthesizing inulin with polymerization degrees ranging from 3 to approximately 40. The enzyme exhibited optimal activity at pH 6.5 and 55 °C, efficiently producing inulin with a yield of 50.6%. Ca2+ can improve the activity and thermostability of this enzyme. To enhance catalytic total activity, site-directed and truncated mutagenesis techniques were applied, resulting in the identification of a mutant, T149S, displaying a significant 57% increase in catalytic total activity. Molecular dynamics simulations unveiled that the heightened flexibility observed in three surface regions positively influenced enzymatic activity. This study not only contributes to the theoretical foundation for inulosucrase engineering but also presents a potential avenue for the production of inulin.


Assuntos
Hexosiltransferases , Inulina , Inulina/metabolismo , Hexosiltransferases/metabolismo , Hexosiltransferases/genética , Hexosiltransferases/química , Simulação de Dinâmica Molecular , Concentração de Íons de Hidrogênio , Sacarose/metabolismo , Peso Molecular , Mutagênese Sítio-Dirigida , Bacillales/enzimologia , Bacillales/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Engenharia de Proteínas , Estabilidade Enzimática , Temperatura , Cálcio/metabolismo
2.
J Cell Mol Med ; 28(20): e70151, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39422159

RESUMO

The placenta plays a critical role in maternal-fetal nutrient transport and fetal protection against drugs. Creating physiological in vitro models to study these processes is crucial, but technically challenging. This study introduces an efficient cell model that mimics the human placental barrier using co-cultures of primary trophoblasts and primary human umbilical vein endothelial cells (HUVEC) on a Transwell®-based system. Monolayer formation was examined over 7 days by determining transepithelial electrical resistance (TEER), permeability of Lucifer yellow (LY) and inulin, localization of transport proteins at the trophoblast membrane (immunofluorescence), and syncytialization markers (RT-qPCR/ELISA). We analysed diffusion-based (caffeine/antipyrine) and transport-based (leucine/Rhodamine-123) processes to study the transfer of physiologically relevant compounds. The latter relies on the adequate localization and function of the amino-acid transporter LAT1 and the drug transporter P-glycoprotein (P-gp) which were studied by immunofluorescence microscopy and application of respective inhibitors (2-Amino-2-norbornanecarboxylic acid (BCH) for LAT1; cyclosporine-A for P-gp). The formation of functional monolayer(s) was confirmed by increasing TEER values, low LY transfer rates, minimal inulin leakage, and appropriate expression/release of syncytialization markers. These results were supported by microscopic monitoring of monolayer formation. LAT1 was identified on the apical and basal sides of the trophoblast monolayer, while P-gp was apically localized. Transport assays confirmed the inhibition of LAT1 by BCH, reducing both intracellular leucine levels and leucine transport to the basal compartment. Inhibiting P-gp with cyclosporine-A increased intracellular Rhodamine-123 concentrations. Our in vitro model mimics key aspects of the human placental barrier. It represents a powerful tool to study nutrient and drug transport mechanisms across the placenta, assisting in evaluating safer pregnancy therapies.


Assuntos
Células Endoteliais da Veia Umbilical Humana , Troca Materno-Fetal , Placenta , Trofoblastos , Humanos , Feminino , Gravidez , Trofoblastos/metabolismo , Placenta/metabolismo , Transporte Biológico , Células Endoteliais da Veia Umbilical Humana/metabolismo , Técnicas de Cocultura , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Modelos Biológicos , Rodamina 123/metabolismo , Leucina/metabolismo , Inulina/metabolismo , Isoquinolinas
3.
J Agric Food Chem ; 72(37): 20513-20526, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39241186

RESUMO

Pectic polysaccharides can beneficially shape the human microbiota. However, individual variability in the microbial response, especially the response between normal-weight (NW) and overweight (OW) people, is rarely understood. Therefore, we performed batch fermentation using inulin (INU), commercial pectin (CP), and pectic polysaccharides extracted from goji berry (GPP) and raspberry (RPP) by microbiota from five normal-weight (NW) and five overweight (OW) donors. The degree of specificity of fiber was negatively correlated to its fermentable rate and microbial response. Meanwhile, we found that microbiota from OW donors had a stronger fiber-degrading capacity than NW donors. The result of correlation between individual basal microbiota and the fermentable rate indicated Dialister, Megamonas, Oscillospiraceae_NK4A214, Prevotella, Ruminococcus, and unidentified_Muribaculaceae may be the key bacteria. In summary, we highlighted a new perspective regarding the interactive relationship between different fibers and fecal microbiota from different donors that may be helpful to design fiber interventions for individuals with different microbiota.


Assuntos
Bactérias , Fezes , Fermentação , Microbioma Gastrointestinal , Sobrepeso , Pectinas , Humanos , Sobrepeso/metabolismo , Sobrepeso/microbiologia , Bactérias/metabolismo , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/genética , Adulto , Masculino , Fezes/microbiologia , Feminino , Pectinas/metabolismo , Fibras na Dieta/metabolismo , Inulina/metabolismo , Adulto Jovem , Rubus/química , Rubus/microbiologia , Rubus/metabolismo , Pessoa de Meia-Idade , Frutas/química , Frutas/microbiologia , Frutas/metabolismo
4.
NPJ Biofilms Microbiomes ; 10(1): 75, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39209925

RESUMO

Spinal cord injury (SCI) results in numerous systemic dysfunctions, including intestinal dysmotility and enteric nervous system (ENS) atrophy. The ENS has capacity to recover following perturbation, yet intestinal pathologies persist. With emerging evidence demonstrating SCI-induced alterations to gut microbiome composition, we hypothesized that microbiome modulation contributes to post-injury enteric recovery. Here, we show that intervention with the dietary fiber, inulin, prevents SCI-induced ENS atrophy and dysmotility in mice. While SCI-associated microbiomes and specific injury-sensitive gut microbes are not sufficient to modulate intestinal dysmotility after injury, intervention with microbially-derived short-chain fatty acid (SCFA) metabolites prevents ENS dysfunctions in injured mice. Notably, inulin-mediated resilience is dependent on IL-10 signaling, highlighting a critical diet-microbiome-immune axis that promotes ENS resilience post-injury. Overall, we demonstrate that diet and microbially-derived signals distinctly impact ENS survival after traumatic spinal injury and represent a foundation to uncover etiological mechanisms and future therapeutics for SCI-induced neurogenic bowel.


Assuntos
Sistema Nervoso Entérico , Ácidos Graxos Voláteis , Microbioma Gastrointestinal , Traumatismos da Medula Espinal , Animais , Traumatismos da Medula Espinal/microbiologia , Camundongos , Ácidos Graxos Voláteis/metabolismo , Camundongos Endogâmicos C57BL , Inulina/metabolismo , Inulina/farmacologia , Modelos Animais de Doenças , Dieta , Fibras na Dieta/administração & dosagem , Interleucina-10/metabolismo , Feminino
5.
Int J Biol Macromol ; 277(Pt 3): 134446, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39098696

RESUMO

Glycoside hydrolase family 91 (GH91) inulin fructotransferase (IFTases) enables biotransformation of fructans into sugar substitutes for dietary intervention in metabolic syndrome. However, the catalytic mechanism underlying the sequential biodegradation of inulin remains unelusive during the biotranformation of fructans. Herein we present the crystal structures of IFTase from Arthrobacter aurescens SK 8.001 in apo form and in complexes with kestose, nystose, or fructosyl nystose, respectively. Two kinds of conserved noncatalytic binding regions are first identified for IFTase-inulin interactions. The conserved interactions of substrates were revealed in the catalytic center that only contained a catalytic residue E205. A switching scaffold was comprised of D194 and Q217 in the catalytic channel, which served as the catalytic transition stabilizer through side chain displacement in the cycling of substrate sliding in/out the catalytic pocket. Such features in GH91 contribute to the catalytic model for consecutive cutting of substrate chain as well as product release in IFTase, and thus might be extended to other exo-active enzymes with an enclosed bottom of catalytic pocket. The study expands the current general catalytic principle in enzyme-substrate complexes and shed light on the rational design of IFTase for fructan biotransformation.


Assuntos
Domínio Catalítico , Hexosiltransferases , Inulina , Inulina/metabolismo , Inulina/química , Hexosiltransferases/metabolismo , Hexosiltransferases/química , Especificidade por Substrato , Modelos Moleculares , Arthrobacter/enzimologia , Catálise , Biocatálise , Frutanos/metabolismo , Frutanos/química , Conformação Proteica
6.
J Agric Food Chem ; 72(32): 18100-18109, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39090787

RESUMO

Inulin has found commercial applications in the pharmaceutical, nutraceutical, and food industries due to its beneficial health effects. The enzymatic biosynthesis of microbial inulin has garnered increasing attention. In this study, molecular modification was applied to Lactobacillus mulieris UMB7800 inulosucrase, an enzyme that specifically produces high-molecular weight inulin, to enhance its catalytic activity and thermostability. Among the 18 variable regions, R5 was identified as a crucial region significantly impacting enzymatic activity by replacing it with more conserved sequences. Site-directed mutagenesis combined with saturated mutagenesis revealed that the mutant A250 V increased activity by 68%. Additionally, after screening candidate mutants by rational design, four single-point mutants, S344D, H434P, E526D, and G531P, were shown to enhance thermostability. The final combinational mutant, M5, exhibited a 66% increase in activity and a 5-fold enhancement in half-life at 55 °C. These findings are significant for understanding the catalytic activity and thermostability of inulosucrase and are promising for the development of microbial inulin biosynthesis platforms.


Assuntos
Proteínas de Bactérias , Estabilidade Enzimática , Hexosiltransferases , Inulina , Lactobacillus , Mutagênese Sítio-Dirigida , Inulina/metabolismo , Inulina/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Hexosiltransferases/genética , Hexosiltransferases/metabolismo , Hexosiltransferases/química , Lactobacillus/enzimologia , Lactobacillus/genética , Lactobacillus/metabolismo , Cinética , Temperatura Alta , Engenharia de Proteínas , Especificidade por Substrato
7.
Nutrients ; 16(15)2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39125327

RESUMO

A fiber-rich diet is considered beneficial for gut health. An inflamed gut with a dysbiotic bacterial community can result in altered fiber metabolism depending on the fiber's physicochemical properties. This study examined the effect of fiber's physicochemical properties on fiber fermentation in the presence of healthy and colitis-associated bacteria. Sixteen fibers with different levels of solubility, complexity, and fermentation rate were used in in vitro fermentation with healthy human gut bacteria. Resistant maltodextrins (RMD), pectin (HMP), inulin (ChIn), and wheat bran (WB) were selected for fermentation using ulcerative colitis (UC)-associated bacteria to assess bacterial dysbiosis effect. UC-associated gut microbiota showed a significant reduction in α-and ß-diversity indices compared to healthy-associated microbiota. The differences in the gut microbiota composition and diversity between the donors resulted in decreased fermentation rates with UC-associated bacteria. Fiber fermentation metabolites, short-chain fatty acids (SCFA) and gas production were significantly lower in the presence of UC-associated bacteria for all four fibers tested. Overall, we conclude that dietary fiber properties and microbial dysbiosis are influential in fiber fermentation and metabolite production in the gut.


Assuntos
Bactérias , Fibras na Dieta , Disbiose , Ácidos Graxos Voláteis , Fermentação , Microbioma Gastrointestinal , Fibras na Dieta/farmacologia , Microbioma Gastrointestinal/fisiologia , Humanos , Disbiose/microbiologia , Bactérias/metabolismo , Bactérias/classificação , Ácidos Graxos Voláteis/metabolismo , Pectinas/metabolismo , Colite Ulcerativa/microbiologia , Inulina/metabolismo , Masculino , Adulto , Feminino , Polissacarídeos
8.
Sci Rep ; 14(1): 15842, 2024 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982163

RESUMO

This work implemented a non-invasive volatile organic compounds (VOCs) monitoring approach to study how food components are metabolised by the gut microbiota in-vitro. The fermentability of a model food matrix rich in dietary fibre (oat bran), and a pure prebiotic (inulin), added to a minimal gut medium was compared by looking at global changes in the volatilome. The substrates were incubated with a stabilised human faecal inoculum over a 24-h period, and VOCs were monitored without interfering with biological processes. The fermentation was performed in nitrogen-filled vials, with controlled temperature, and tracked by automated headspace-solid-phase microextraction coupled with gas chromatography-mass spectrometry. To understand the molecular patterns over time, we applied a multivariate longitudinal statistical framework: repeated measurements-ANOVA simultaneous component analysis. The methodology was able to discriminate the studied groups by looking at VOCs temporal profiles. The volatilome showed a time-dependency that was more distinct after 12 h. Short to medium-chain fatty acids showed increased peak intensities, mainly for oat bran and for inulin, but with different kinetics. At the same time, alcohols, aldehydes, and esters showed distinct trends with discriminatory power. The proposed approach can be applied to study the intertwined pathways of gut microbiota food components interaction in-vitro.


Assuntos
Fezes , Microbioma Gastrointestinal , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo , Humanos , Microbioma Gastrointestinal/fisiologia , Fezes/microbiologia , Fezes/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Fermentação , Fibras na Dieta/metabolismo , Inulina/metabolismo , Microextração em Fase Sólida/métodos
9.
NPJ Biofilms Microbiomes ; 10(1): 63, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080292

RESUMO

Interventions involving dietary fibers are known to benefit host health. A leading contribution of gut microbiota is commonly recognized with production of short chain fatty acids (SCFA) suspected to play a key role. However, the detailed mechanisms are largely unknown, and apart from a well-described bifidogenic effect of some fibers, results for other bacterial taxa are often incongruent between studies. We performed pooled analyses of 16S rRNA gene data derived from intervention studies (n = 14) based on three fibers, namely, inulin-type fructans (ITF), resistant starch (RS), and arabinoxylan-oligosaccharides (AXOS), harmonizing the bioinformatics workflow to reveal taxa stimulated by those substrates, specifically focusing on the SCFA-production potential. The results showed an increased butyrate production potential after ITF (p < 0.05) and RS (p < 0.1) treatment via an increase in bacteria exhibiting the enzyme butyryl-CoA:acetate CoA-transferase (but) that was governed by Faecalibacterium, Anaerostipes (ITF) and Agathobacter (RS) respectively. AXOS did not promote an increase in butyrate producers, nor were pathways linked to propionate production stimulated by any intervention. A bifidogenic effect was observed for AXOS and ITF, which was only partly associated with the behavior of but-containing bacteria and largely represented a separate response. Low and high Ruminococcus abundances pre-intervention for ITF and RS, respectively, promoted an increase in but-containing taxa (p < 0.05) upon interventions, whereas initial Prevotella abundance was negatively associated with responses of butyrate producers for both fibers. Collectively, our data demonstrate targeted stimulation of specific taxa by individual fibers increasing the potential to synthesize butyrate, where gut microbiota composition pre-intervention strongly controlled outcomes.


Assuntos
Bactérias , Butiratos , Fibras na Dieta , Microbioma Gastrointestinal , RNA Ribossômico 16S , Xilanos , Fibras na Dieta/metabolismo , Butiratos/metabolismo , Xilanos/metabolismo , RNA Ribossômico 16S/genética , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo , Humanos , Coenzima A-Transferases/genética , Coenzima A-Transferases/metabolismo , Ácidos Graxos Voláteis/metabolismo , Inulina/metabolismo , Amido/metabolismo , Oligossacarídeos/metabolismo , Faecalibacterium/genética , Biologia Computacional/métodos
10.
J Agric Food Chem ; 72(30): 17030-17040, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39034843

RESUMO

Carbohydrate degradation is crucial for living organisms due to their essential functions in providing energy and composing various metabolic pathways. Nevertheless, in the catalytic cycle of polysaccharide degradation, the details of how the substrates bind and how the products release need more case studies. Here, we choose an inulin fructotransferase (SpIFTase) as a model system, which can degrade inulin into functionally difructose anhydride I. At first, the crystal structures of SpIFTase in the absence of carbohydrates and complex with fructosyl-nystose (GF4), difructose anhydride I, and fructose are obtained, giving the substrate trajectory and product path of SpIFTase, which are further supported by steered molecular dynamics simulations (MDSs) along with mutagenesis. Furthermore, structural topology variations at the active centers of inulin fructotransferases are suggested as the structural base for product release, subsequently proven by substitution mutagenesis and MDSs. Therefore, this study provides a case in point for a deep understanding of the catalytic cycle with substrate trajectory and product path.


Assuntos
Hexosiltransferases , Inulina , Hexosiltransferases/química , Hexosiltransferases/metabolismo , Hexosiltransferases/genética , Inulina/metabolismo , Inulina/química , Especificidade por Substrato , Simulação de Dinâmica Molecular , Domínio Catalítico , Biocatálise , Catálise , Frutose/metabolismo , Frutose/química
11.
Food Chem ; 457: 140107, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39032479

RESUMO

Bacillus stercoris PSSR12 (B. stercoris PE), an isolate from rice field soils, was identified via 16s rRNA sequencing. The synthesis of the inulin and inulin producing enzyme (IPE) in B. stercoris PE was verified using SDS-PAGE and FTIR. This study aimed to assess the impact of B. stercoris PE treatment on in vitro inhibition of α-amylase and α-glucosidase from traditional and commercial rice varieties of South India. Additionally, the study investigated enzymatic inhibition and mRNA expression of starch synthesis genes (RAmy1a, GBSSIa, SBEIIa, and SBEIIb). Glucose transporter gene expression (GLUT1 and GLUT4) patterns were analyzed in 3T3-L1 adipocytes to evaluate glucose uptake in B. stercoris PE treated rice varieties. The application of B. stercoris PE enhanced grain quality by imparting starch ultra-structural rigidity, inhibiting starch metabolizing enzymes, and inducing molecular changes in starch synthesis genes. This approach holds promise for managing type II diabetes mellitus and potentially reducing insulin dependence.


Assuntos
Glucose , Inulina , Oryza , Amido , alfa-Amilases , Oryza/metabolismo , Oryza/química , Oryza/microbiologia , Inulina/metabolismo , Inulina/química , Glucose/metabolismo , Amido/metabolismo , Amido/química , alfa-Amilases/metabolismo , alfa-Amilases/genética , Bacillus/metabolismo , Bacillus/genética , Bacillus/química , Camundongos , alfa-Glucosidases/metabolismo , alfa-Glucosidases/genética , Animais
12.
Gigascience ; 132024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38869151

RESUMO

BACKGROUND: The Coreopsideae tribe, a subset of the Asteraceae family, encompasses economically vital genera like Dahlia, Cosmos, and Bidens, which are widely employed in medicine, horticulture, ecology, and food applications. Nevertheless, the lack of reference genomes hinders evolutionary and biological investigations in this tribe. RESULTS: Here, we present 3 haplotype-resolved chromosome-level reference genomes of the tribe Coreopsideae, including 2 popular flowering plants (Dahlia pinnata and Cosmos bipinnatus) and 1 invasive weed plant (Bidens alba), with assembled genome sizes 3.93 G, 1.02 G, and 1.87 G, respectively. We found that Gypsy transposable elements contribute mostly to the larger genome size of D. pinnata, and multiple chromosome rearrangements have occurred in tribe Coreopsideae. Besides the shared whole-genome duplication (WGD-2) in the Heliantheae alliance, our analyses showed that D. pinnata and B. alba each underwent an independent recent WGD-3 event: in D. pinnata, it is more likely to be a self-WGD, while in B. alba, it is from the hybridization of 2 ancestor species. Further, we identified key genes in the inulin metabolic pathway and found that the pseudogenization of 1-FEH1 and 1-FEH2 genes in D. pinnata and the deletion of 3 key residues of 1-FFT proteins in C. bipinnatus and B. alba may probably explain why D. pinnata produces much more inulin than the other 2 plants. CONCLUSIONS: Collectively, the genomic resources for the Coreopsideae tribe will promote phylogenomics in Asteraceae plants, facilitate ornamental molecular breeding improvements and inulin production, and help prevent invasive weeds.


Assuntos
Evolução Molecular , Genoma de Planta , Inulina , Poliploidia , Inulina/metabolismo , Asteraceae/genética , Filogenia , Bidens/genética , Bidens/metabolismo , Tamanho do Genoma
13.
J Agric Food Chem ; 72(26): 14663-14677, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38887904

RESUMO

Pomegranate juice (PJ) and inulin have been reported to ameliorate diet-induced metabolic disorders by regulating gut microbiota dysbiosis. However, there was a lack of clinical evidence for the combined effects of PJ and inulin on regulating gut microbiota in individuals with metabolic disorders. A double-blind, parallel, randomized, placebo-controlled trial was conducted, and 68 overweight/obese individuals (25 ≤ BMI ≤ 35 kg/m2) were randomly assigned to receive 200 mL/d PJ, PJ supplemented with inulin, or placebo for 3 weeks. Our results showed that PJ and PJ+inulin did not significantly alter the levels of anthropometric and blood biochemical indicators after 3 weeks of treatment. However, there was an increasingly significant impact from placebo to PJ to PJ+inulin on the composition of gut microbiota. Detailed bacterial abundance analysis further showed that PJ+inulin treatment more profoundly resulted in significant changes in the abundance of gut microbiota at each taxonomic level than PJ. Moreover, PJ+inulin treatment also promoted the production of microbiota-associated short-chain fatty acids and pomegranate polyphenol metabolites, which correlated with the abundance of the bacterial genus. Our results suggested that PJ supplemented with inulin modulates gut microbiota composition and thus promotes the production of microbiota-associated metabolites that exert potential beneficial effects in overweight/obese subjects.


Assuntos
Bactérias , Sucos de Frutas e Vegetais , Microbioma Gastrointestinal , Inulina , Obesidade , Sobrepeso , Punica granatum , Humanos , Inulina/farmacologia , Inulina/administração & dosagem , Inulina/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Adulto , Obesidade/metabolismo , Obesidade/microbiologia , Obesidade/dietoterapia , Obesidade/tratamento farmacológico , Punica granatum/química , Punica granatum/metabolismo , Feminino , Pessoa de Meia-Idade , Sobrepeso/metabolismo , Sobrepeso/microbiologia , Sobrepeso/tratamento farmacológico , Sobrepeso/dietoterapia , Método Duplo-Cego , Sucos de Frutas e Vegetais/análise , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Bactérias/isolamento & purificação , Bactérias/efeitos dos fármacos , Suplementos Nutricionais/análise , Ácidos Graxos Voláteis/metabolismo , Adulto Jovem
14.
Cell Rep ; 43(6): 114292, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38823020

RESUMO

Interleukin (IL)-22 promotes host-microbiota homeostasis. We sought to identify microbiota metabolite(s) that drive intestinal IL-22 production. We observed that exposing Peyer's patch cells (PPCs), ex vivo, to fecal supernatants (FSs) recapitulates fermentable fiber- and microbiota-dependent IL-22 production, and cellular sources thereof, thus supporting the use of this model. An interrogation of FSs generated from mice fed the fermentable fiber inulin (FS-Inu) revealed that its IL-22-inducing activity is mediated by heat-labile protein. Fractionation of FS-Inu by ion-exchange chromatography, and subsequent proteomic analysis of IL-22-inducing fractions, indicates that outer membrane protein A (OmpA) might be a microbial driver of IL-22 expression. Concomitantly, recombinant OmpA from Parabacteroides goldsteinii, which is enriched by an inulin diet, induces IL-22 production and expression of the IL-22-dependent genes REG3γ and -ß, in PPCs and mice. Thus, OmpA is one bacterial inducer of IL-22 expression, potentially linking diet, mucosal immune homeostasis, and gut health.


Assuntos
Proteínas da Membrana Bacteriana Externa , Interleucina 22 , Animais , Camundongos , Proteínas da Membrana Bacteriana Externa/metabolismo , Fezes/microbiologia , Microbioma Gastrointestinal , Interleucina 22/metabolismo , Interleucinas/metabolismo , Inulina/metabolismo , Camundongos Endogâmicos C57BL , Proteínas Associadas a Pancreatite/metabolismo
15.
Immunol Cell Biol ; 102(7): 593-604, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38757764

RESUMO

Delta inulin, or Advax, is a polysaccharide vaccine adjuvant that significantly enhances vaccine-mediated immune responses against multiple pathogens and was recently licensed for use in the coronavirus disease 2019 (COVID-19) vaccine SpikoGen. Although Advax has proven effective as an immune adjuvant, its specific binding targets have not been characterized. In this report, we identify a cellular receptor for Advax recognition. In vitro uptake of Advax particles by macrophage cell lines was substantially greater than that of latex beads of comparable size, suggesting an active uptake mechanism by phagocytic cells. Using a lectin array, Advax particles were recognized by lectins specific for various carbohydrate structures including mannosyl, N-acetylgalactosamine and galactose moieties. Expression in nonphagocytic cells of dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN), a C-type lectin receptor, resulted in enhanced uptake of fluorescent Advax particles compared with mock-transfected cells. Advax uptake was reduced with the addition of ethylenediaminetetraacetic acid and mannan to cells, which are known inhibitors of DC-SIGN function. Finally, a specific blockade of DC-SIGN using a neutralizing antibody abrogated Advax uptake in DC-SIGN-expressing cells. Together, these results identify DC-SIGN as a putative receptor for Advax. Given the known immunomodulatory role of DC-SIGN, the findings described here have implications for the use of Advax adjuvants in humans and inform future mechanistic studies.


Assuntos
Adjuvantes Imunológicos , Moléculas de Adesão Celular , Inulina , Lectinas Tipo C , Receptores de Superfície Celular , Humanos , Adjuvantes Imunológicos/farmacologia , Adjuvantes de Vacinas/metabolismo , Moléculas de Adesão Celular/metabolismo , Linhagem Celular , COVID-19/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Inulina/metabolismo , Inulina/análogos & derivados , Lectinas Tipo C/metabolismo , Macrófagos/metabolismo , Macrófagos/imunologia , Mananas/metabolismo , Receptores de Superfície Celular/metabolismo
16.
Food Chem ; 453: 139597, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-38788653

RESUMO

Fructansucrases produce fructans by polymerizing the fructose moiety released from sucrose. Here, we describe the recombinant expression and characterization of a unique fructansucrase from Lactiplantibacillus plantarum DKL3 that showed low sequence similarity with previously characterized fructansucrases. The optimum pH and temperature of fructansucrase were found to be 4.0 and 35 °C, respectively. Enzyme activity increased in presence of Ca2+ and distinctly in presence of Mn2+. The enzyme was characterized as an inulosucrase (LpInu), based on the production of an inulin-type fructan as assessed byNMR spectroscopy and methylation analysis. In addition to ß-2,1-linkages, the inulin contained a few ß-2,1,6-linked branchpoints. High-performance size exclusion chromatography with refractive index detection (HPSEC-RI) revealed the production of inulin with a lower molecular weight compared to other characterized bacterial inulin. LpInu and its inulin product represent novel candidates to be explored for possible food and biomedical applications.


Assuntos
Proteínas de Bactérias , Hexosiltransferases , Inulina , Hexosiltransferases/genética , Hexosiltransferases/metabolismo , Hexosiltransferases/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Inulina/química , Inulina/metabolismo , Concentração de Íons de Hidrogênio , Temperatura , Estabilidade Enzimática , Peso Molecular , Lactobacillaceae/enzimologia , Lactobacillaceae/genética , Lactobacillaceae/metabolismo , Lactobacillaceae/química
17.
BMC Microbiol ; 24(1): 183, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38796418

RESUMO

BACKGROUND: Prebiotic fibers are non-digestible substrates that modulate the gut microbiome by promoting expansion of microbes having the genetic and physiological potential to utilize those molecules. Although several prebiotic substrates have been consistently shown to provide health benefits in human clinical trials, responder and non-responder phenotypes are often reported. These observations had led to interest in identifying, a priori, prebiotic responders and non-responders as a basis for personalized nutrition. In this study, we conducted in vitro fecal enrichments and applied shotgun metagenomics and machine learning tools to identify microbial gene signatures from adult subjects that could be used to predict prebiotic responders and non-responders. RESULTS: Using short chain fatty acids as a targeted response, we identified genetic features, consisting of carbohydrate active enzymes, transcription factors and sugar transporters, from metagenomic sequencing of in vitro fermentations for three prebiotic substrates: xylooligosacharides, fructooligosacharides, and inulin. A machine learning approach was then used to select substrate-specific gene signatures as predictive features. These features were found to be predictive for XOS responders with respect to SCFA production in an in vivo trial. CONCLUSIONS: Our results confirm the bifidogenic effect of commonly used prebiotic substrates along with inter-individual microbial responses towards these substrates. We successfully trained classifiers for the prediction of prebiotic responders towards XOS and inulin with robust accuracy (≥ AUC 0.9) and demonstrated its utility in a human feeding trial. Overall, the findings from this study highlight the practical implementation of pre-intervention targeted profiling of individual microbiomes to stratify responders and non-responders.


Assuntos
Ácidos Graxos Voláteis , Fezes , Fermentação , Microbioma Gastrointestinal , Prebióticos , Prebióticos/análise , Humanos , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Adulto , Ácidos Graxos Voláteis/metabolismo , Família Multigênica , Aprendizado de Máquina , Metagenômica/métodos , Biomarcadores/metabolismo , Bactérias/genética , Bactérias/metabolismo , Bactérias/classificação , Feminino , Masculino , Inulina/metabolismo , Adulto Jovem , Metabolismo dos Carboidratos
18.
Food Chem ; 454: 139839, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38810444

RESUMO

Probiotic lactic acid bacteria have been widely studied, but much less was focused on probiotic yeasts in food systems. In this study, probiotic Saccharomyces cerevisiae var. boulardii CNCM I-745 was employed to prepare ice cream added with and without inulin (1%, w/v). Metabolomics analysis on the effect of inulin showed 84 and 147 differentially expressed metabolites identified in the ice cream samples from day 1 and day 30 of storage (-18 °C), respectively. Various potential functional metabolites were found, including citric acid, ornithine, D-glucuronic acid, sennoside A, stachyose, maltotetraose, maltopentaose, maltohexaose, maltoheptaose, cis-aconitic acid, gamma-aminobutyric acid, L-threonine, L-glutamic acid, tryptophan, benzoic acid, and trehalose. Higher expression of these metabolites suggested their possible roles through relevant metabolic pathways in improving survivability of the probiotic yeast and functionality of ice cream. This study provides further understanding on the metabolic characteristics of probiotic yeast that potentially affect the functionality of ice cream.


Assuntos
Sorvetes , Inulina , Metabolômica , Prebióticos , Probióticos , Saccharomyces cerevisiae , Simbióticos , Inulina/metabolismo , Probióticos/metabolismo , Simbióticos/análise , Prebióticos/análise , Saccharomyces cerevisiae/metabolismo , Sorvetes/análise , Sorvetes/microbiologia , Saccharomyces boulardii/metabolismo , Saccharomyces boulardii/química
19.
Gut Microbes ; 16(1): 2338946, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38656273

RESUMO

Synbiotics combine the concepts of probiotics and prebiotics to synergistically enhance the health-associated effects of both components. Previously, we have shown that the intestinal persistence of inulin-utilizing L. plantarum Lp900 is significantly increased in rats fed an inulin-supplemented, high-calcium diet. Here we employed a competitive population dynamics approach to demonstrate that inulin and GOS can selectively enrich L. plantarum strains that utilize these substrates for growth during in vitro cultivation, but that such enrichment did not occur during intestinal transit in rats fed a GOS or inulin-supplemented diet. The intestinal persistence of all L. plantarum strains increased irrespective of their prebiotic utilization phenotype, which was dependent on the calcium level of the diet. Analysis of fecal microbiota and intestinal persistence decline rates indicated that prebiotic utilization capacity did not selectively stimulate intestinal persistence in prebiotic supplemented diets. Moreover, microbiota and organic acid profile analyses indicate that the prebiotic utilizing probiotic strains are vastly outcompeted by the endogenous prebiotic-utilizing microbiota, and that the collective enhanced persistence of all L. plantarum strains is most likely explained by their well-established tolerance to organic acids.


Assuntos
Fezes , Microbioma Gastrointestinal , Inulina , Prebióticos , Animais , Prebióticos/administração & dosagem , Inulina/metabolismo , Inulina/administração & dosagem , Ratos , Fezes/microbiologia , Lactobacillus plantarum/metabolismo , Lactobacillus plantarum/fisiologia , Masculino , Probióticos/administração & dosagem , Simbióticos/administração & dosagem , Ratos Sprague-Dawley
20.
Gut Microbes ; 16(1): 2347021, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38685762

RESUMO

Inulin, an increasingly studied dietary fiber, alters intestinal microbiota. The aim of this study was to assess whether inulin decreases intestinal colonization by multidrug resistant E. coli and to investigate its potential mechanisms of action. Mice with amoxicillin-induced intestinal dysbiosis mice were inoculated with extended spectrum beta-lactamase producing E. coli (ESBL-E. coli). The combination of inulin and pantoprazole (IP) significantly reduced ESBL-E. coli fecal titers, whereas pantoprazole alone did not and inulin had a delayed and limited effect. Fecal microbiome was assessed using shotgun metagenomic sequencing and qPCR. The efficacy of IP was predicted by increased abundance of 74 taxa, including two species of Adlercreutzia. Preventive treatments with A. caecimuris or A. muris also reduced ESBL-E. coli fecal titers. Fecal microbiota of mice effectively treated by IP was enriched in genes involved in inulin catabolism, production of propionate and expression of beta-lactamases. They also had increased beta-lactamase activity and decreased amoxicillin concentration. These results suggest that IP act through production of propionate and degradation of amoxicillin by the microbiota. The combination of pantoprazole and inulin is a potential treatment of intestinal colonization by multidrug-resistant E. coli. The ability of prebiotics to promote propionate and/or beta-lactamase producing bacteria may be used as a screening tool to identify potential treatments of intestinal colonization by multidrug resistant Enterobacterales.


Assuntos
Amoxicilina , Farmacorresistência Bacteriana Múltipla , Escherichia coli , Fezes , Microbioma Gastrointestinal , Inulina , Pantoprazol , Animais , Inulina/farmacologia , Inulina/metabolismo , Camundongos , Microbioma Gastrointestinal/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Fezes/microbiologia , Amoxicilina/farmacologia , Pantoprazol/farmacologia , beta-Lactamases/metabolismo , beta-Lactamases/genética , Disbiose/microbiologia , Disbiose/tratamento farmacológico , Antibacterianos/farmacologia , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Feminino , Prebióticos/administração & dosagem
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