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1.
Food Chem ; 367: 130696, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34364145

RESUMO

Oligosaccharides especially prebiotics take high attention in the development of foods because of their physiological properties in human health. They are generally synthetized enzymatically via transferases or hydrolases from mold or bacteria. The fact is that such oligosaccharides synthetized by probiotic bacteria, should be utilized by these microorganisms. This study focused on the production of oligosaccharides with prebiotic potential by crude enzyme preparation from bifidobacteria. Both monosubstrates and bisubstrates systems together with TLC and HPLC techniques, were applied. The crude enzyme preparation has different hydrolase activities such as α-glucosidase (2U/mL), ß-glucosidase (0.3 U/mL), α-galactosidase (1.2 U/mL), ß-galactosidase (0.4 U/mL), ß-fructosidase (11.5 U/mL). Additionally, it also has transglycosylation activities on lactose, lactulose, maltose and sucrose substrates. Two or three types of oligosaccharides were detected. The glycosyltransferase activity peaked at 45 °C, pH 6.6 and 30 g/100 mL substrate concentration. Significant high amount of oligosaccharides were formed in the case of lactose:sucrose combination than others. Both glucooligosaccharides and galactooligosaccharides are detected in the reaction mixtures of bisubstrate. When the lactose is present, the galactosyltransferation is predominated. One-one new types of oligosaccharides were detected in the reaction mixture of bioconversion. Among newly synthetized oligosaccharides, the fraction namely OS4 was utilized by probiotic bifidobacteria only. In conclusion, new types of galacto- and glucooligosaccharides with high prebiotic potentials were synthetized by the crude enzyme from probiotic Bifidobacterium strains.


Assuntos
Bifidobacterium , Prebióticos , Humanos , Lactulose , Oligossacarídeos , beta-Galactosidase
2.
Appl Microbiol Biotechnol ; 105(20): 7721-7730, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34596721

RESUMO

The steadily increasing prevalence of Alzheimer's disease (AD) worldwide and the lack of effective therapeutic agent attract novel therapeutic approach in recent years. In view of the close relationships between gut microbiota and AD, probiotics have been suggested as potential therapeutic options for AD in recent years. The present review discussed the research progresses concerning the effects of probiotics administration to combat AD. A total of 35 studies, including 26 animal model studies and 9 human studies, were included herein. Among the 26 animal model studies, 24 used mice model, and 2 used Caenorhabditis elegans and Drosophila melanogaster AD models, respectively. As for probiotics, a total of 13 studies employed single-strain probiotic, and the rest studies used multi-strain probiotics (ranged from 2 to 9 probiotic strains), 4 used probiotic-fermented milk or probiotic-fermented soybean, 2 studies used engineered probiotic strain, and 4 studies focused on the combined effect of probiotics with AD drug memantine, selenium, or exercise. Bifidobacterium and Lactobacillus species were the most frequently used probiotics in the included studies. Overall, currently available studies showed that probiotic administration conferred neuroprotective benefits and could attenuate cognitive deficits and modulate gut microbiota dysbiosis, which may be related to oxidative and inflammatory pathways. Several perspectives on future studies on this topic are proposed. Thus, probiotics seem to be an attractive approach to combat AD, which deserves to be further studied by well-designed large-scale clinical studies. KEY POINTS: •We discussed the recent progresses concerning the effects of probiotics administration to combat AD. •A total of 35 associated studies consisted of 26 animal model studies and 9 human studies were included. •Most studies found that probiotic administration conferred neuroprotective benefits and could attenuate cognitive deficits.


Assuntos
Doença de Alzheimer , Microbioma Gastrointestinal , Probióticos , Doença de Alzheimer/tratamento farmacológico , Animais , Bifidobacterium , Drosophila melanogaster , Camundongos
3.
Appl Microbiol Biotechnol ; 105(21-22): 8427-8440, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34625821

RESUMO

Aging is associated with gut microbiota alterations, characterized by changes in intestinal microbial diversity and composition. However, no study has yet focused on investigating age-related changes in the low-abundant but potentially beneficial subpopulations of gut lactic acid bacteria (LAB) and Bifidobacterium. Our study found that the subjects' age correlated negatively with the alpha diversity of the gut bifidobacterial microbiota, and such correlation was not observed in the gut LAB subpopulation. Principal coordinate analysis (PCoA) and analysis of distribution of operational taxonomic units (OTUs) revealed that the structure and composition of the gut bifidobacterial subpopulation of the longevous elderly group were rather different from that of the other three age groups. The same analyses were applied to identify age-dependent characteristics of the gut LAB subpopulation, and the results revealed that the gut LAB subpopulation of young adults was significantly different from that of all three elderly groups. Our study identified several potentially beneficial bacteria (e.g., Bifidobacterium breve and Bifidobacterium longum) that were enriched in the longevous elderly group (P < 0.05), and the relative abundance of Bifidobacterium adolescentis decreased significantly with the increase in age (P < 0.05). Although both bifidobacteria and LAB are generally considered as health-promoting taxa, their age-dependent distribution varied from each other, suggesting their different life stage changes and potentially different functional roles. This study provided novel species-level gut bifidobacterial and LAB microbiota profiles of a large cohort of subjects and identified several age-or longevity-associated features and biomarkers. KEY POINTS: • The alpha diversity of the gut bifidobacterial microbiota decreased with age, while LAB did not change. • The structure and composition of the gut bifidobacterial subpopulation of the longevous elderly group were rather different from that of the other three age groups. • Several potentially beneficial bacteria (e.g., Bifidobacterium breve and Bifidobacterium longum) that were enriched in the longevous elderly group.


Assuntos
Bifidobacterium longum , Microbioma Gastrointestinal , Lactobacillales , Idoso , Envelhecimento , Bifidobacterium , Fezes , Humanos
4.
FASEB J ; 35(11): e21977, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34613640

RESUMO

Xylo-oligosaccharide (XOS), which is considered as a potential prebiotic, exhibits multiple beneficial effects on modulation of gut microbiota, strength of intestinal barrier, and inhibition of intestinal inflammation. The objective of this study is to investigate whether XOS protects against Salmonella infection by modulating gut microbiota, enhancing the intestinal barrier, and resisting colonization. C57BL/6 male mice received water supplementation with 5% XOS for 14 days before Salmonella Typhimurium infection. The results showed that XOS suppressed the Salmonella-induced inflammation, but had limited effects on tight junction molecules and mRNA expression of mucus proteins, except for claudin-1 in the colon. Data of 16S rDNA sequencing indicated that XOS modulated gut microbiota composition by significantly stimulating Bifidobacterium animalis (B. animalis), and reducing Salmonella counts. Therefore, the potential protective effects of B. animalis against Salmonella challenge were investigated as well. Bifidobacterium animalis subsp lactis BB-12 (BB12), which could markedly increase in XOS, was selected to treat mice. Similarly, Salmonella-induced inflammatory reactions were alleviated by BB12 but tight junction molecules and mucin proteins in the colonic tissues were not affected. Administration of BB12 remarkably decreased the copies of Salmonella in cecal digesta post Salmonella infection. Additionally, the decrease concentrations of cecal propionate and total short-chain fatty acids (SCFAs) in Salmonella-infected mice were reversed by BB12 treatment, and propionate performed a strong inhibitory effect on Salmonella growth in vitro. Besides that, BB12 could directly restrict Salmonella proliferation in vitro. Moreover, BB12 reduced the adhesion ability of Salmonella on the Caco-2 cells model. Our results suggest that XOS could be considered as a candidate of functional food to protect against Salmonella infection by stimulating Bifidobacterium, which then resists Salmonella colonization by maintaining the intestinal SCFAs levels and suppressing adhesibility.


Assuntos
Bifidobacterium/efeitos dos fármacos , Inflamação/tratamento farmacológico , Probióticos , Infecções por Salmonella/tratamento farmacológico , Salmonella typhimurium/efeitos dos fármacos , Xilose , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Intestinos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Probióticos/farmacologia , Probióticos/uso terapêutico , Xilose/análogos & derivados , Xilose/farmacologia , Xilose/uso terapêutico
5.
J Agric Food Chem ; 69(38): 11311-11321, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34523917

RESUMO

Abundant conjugated linoleic acid (CLA) producers exist among Bifidobacterium species. This CLA production is related to the mitigation of LA toxicity. However, there is still a lack of information on the metabolic response underlying this detoxification strategy. In this study, six bifidobacteria strains belonging to three different species were used to characterize growth and CLA accumulation in the presence of LA. A combination of non-targeted metabolomics techniques and biochemical indicators were used to explore metabolic profile changes in response to LA and the expression of important factors driving CLA production in Bifidobacterium species. The results suggested that free LA had growth inhibitory effects on bifidobacteria, resulting in a global metabolic stress response that caused metabolic reprogramming on all tested strains and promoted malondialdehyde production, inducing a redox imbalance. In particular, a strong decrease in reduced glutathione level was observed in Bifidobacterium breve CCFM683 [log2(FC) = -3.29]. Furthermore, LA-induced oxidative stress is an important factor driving high CLA production in certain strains.


Assuntos
Bifidobacterium , Ácidos Linoleicos Conjugados , Ácido Linoleico , Metaboloma , Metabolômica
6.
Front Cell Infect Microbiol ; 11: 694443, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34490139

RESUMO

Postpartum depression (PPD) is a mental disorder that affects pregnant women around the world, with serious consequences for mothers, families, and children. Its pathogenesis remains unclear, and medications for treating PPD that can be used during lactation remain to be identified. 919 syrup (919 TJ) is a Chinese herbal medicine that has been shown to be beneficial in the treatment of postpartum depression in both clinical and experimental studies. The mechanism of action of 919 TJ is unclear. 919 syrup is ingested orally, making the potential interaction between the drug and the gut microbiome impossible to ignore. We therefore hypothesized that 919 syrup could improve the symptoms of postpartum depression by affecting the structure and function of the intestinal flora, thereby altering hippocampal metabolism. We compared changes in hippocampal metabolism, fecal metabolism, and intestinal microflora of control BALB/c mice, mice with induced untreated PPD, and mice with induced PPD treated with 919 TJ, and found that 4-aminobutyric acid (GABA) in the hippocampus corresponded with PPD behaviors. Based on changes in GABA levels, multiple key gut bacterial species (Mucispirillum schaedleri, Bifidobacterium pseudolongum, Desulfovibrio piger, Alloprevotella tannerae, Bacteroides sp.2.1.33B and Prevotella sp. CAG:755) were associated with PPD. Metabolic markers that may represent the function of the intestinal microbiota in mice with PPD were identified (Met-Arg, urocanic acid, thioetheramide-PC, L-pipecolic acid, and linoleoyl ethanolamide). The relationship between these factors is not a simple one-to-one correspondence, but more likely a network of staggered functions. We therefore believe that the composition and function of the entire intestinal flora should be emphasized in research studying the gut and PPD, rather than changes in the abundance of individual bacterial species. The introduction of this concept of "GutBalance" may help clarify the relationship between gut bacteria and systemic disease.


Assuntos
Depressão Pós-Parto , Microbioma Gastrointestinal , Animais , Bactérias , Bacteroidetes , Bifidobacterium , Depressão Pós-Parto/tratamento farmacológico , Desulfovibrio , Feminino , Ácido Glutâmico , Hipocampo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Gravidez , Ácido gama-Aminobutírico
7.
Int J Mol Sci ; 22(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34502130

RESUMO

Bifidobacteria are some of the major agents that shaped the immune system of many members of the animal kingdom during their evolution. Over recent years, the question of concrete mechanisms underlying the immunomodulatory properties of bifidobacteria has been addressed in both animal and human studies. A possible candidate for this role has been discovered recently. The PFNA cluster, consisting of five core genes, pkb2, fn3, aaa-atp, duf58, tgm, has been found in all gut-dwelling autochthonous bifidobacterial species of humans. The sensory region of the species-specific serine-threonine protein kinase (PKB2), the transmembrane region of the microbial transglutaminase (TGM), and the type-III fibronectin domain-containing protein (FN3) encoded by the I gene imply that the PFNA cluster might be implicated in the interaction between bacteria and the host immune system. Moreover, the FN3 protein encoded by one of the genes making up the PFNA cluster, contains domains and motifs of cytokine receptors capable of selectively binding TNF-α. The PFNA cluster could play an important role for sensing signals of the immune system. Among the practical implications of this finding is the creation of anti-inflammatory drugs aimed at alleviating cytokine storms, one of the dire consequences resulting from SARS-CoV-2 infection.


Assuntos
Proteínas de Bactérias/genética , Bifidobacterium/fisiologia , COVID-19/terapia , Proteínas Serina-Treonina Quinases/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , COVID-19/imunologia , COVID-19/virologia , Síndrome da Liberação de Citocina/imunologia , Síndrome da Liberação de Citocina/prevenção & controle , Citocinas/química , Citocinas/metabolismo , Humanos , Sistema Imunitário , Óperon/genética , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , SARS-CoV-2/isolamento & purificação
8.
Syst Appl Microbiol ; 44(5): 126247, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34482030

RESUMO

Bifidobacterium is one of the dominating bacterial genera in the honey bee gut, and they are the key degrader of diet polysaccharides for the host. Previous genomic analysis shows that they belong to separate phylogenetic clusters and exhibited different functional potentials in hemicellulose digestion. Here, three novel strains from the genus Bifidobacterium were isolated from the guts of the honey bee (Apis mellifera). Phylogenomic analysis showed that the isolates could be grouped into four phylogenetic clusters. The average nucleotide identity values between strains from different clusters are <95%, while strains in Cluster IV belong to the characterized species Bifidobacterium asteroides. Carbohydrate-active enzyme annotation confirmed that the metabolic capacity for carbohydrates varied between clusters of strains. Cells are Gram-positive rods; they grew both anaerobically and in a CO2-enriched atmosphere. All strains grew at a temperature range of 20-42 °C, with optimum growth at 35 °C. The pH range for growth was 5-9. Strains from different phylogenetic clusters varied in multiple phenotypic and chemotaxonomic characterizations. Thus, we propose three novel species Bifidobacterium apousia sp. nov. whose type strain is W8102T (=CGMCC 1.18893 T = JCM 34587 T), Bifidobacterium choladohabitans sp. nov., whose type strain is B14384H11T (=CGMCC 1.18892 T = JCM 34586 T), and Bifidobacterium polysaccharolyticum sp. nov. whose type strain is W8117T (=CGMCC 1.18894 T = JCM 34588 T).


Assuntos
Abelhas/microbiologia , Bifidobacterium , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Bifidobacterium/classificação , Bifidobacterium/isolamento & purificação , DNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
9.
Nutrients ; 13(9)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34579068

RESUMO

Treatment for non-alcoholic fatty liver disease (NAFLD) currently consists of lifestyle modifications such as a low-fat diet, weight loss, and exercise. The gut microbiota forms part of the gut-liver axis and serves as a potential target for NAFLD treatment. We investigated the effect of probiotics on hepatic steatosis, fibrosis, and biochemical blood tests in patients with NAFLD. At the small intestinal mucosal level, we examined the effect of probiotics on the expression of CD4+ and CD8+ T lymphocytes, as well as the tight junction protein zona occluden-1 (ZO-1). This was a randomized, double-blind, placebo-controlled trial involving ultrasound-diagnosed NAFLD patients (n = 39) who were supplemented with either a probiotics sachet (MCP® BCMC® strains) or a placebo for a total of 6 months. Multi-strain probiotics (MCP® BCMC® strains) containing six different Lactobacillus and Bifidobacterium species at a concentration of 30 billion CFU were used. There were no significant changes at the end of the study in terms of hepatic steatosis (probiotics: -21.70 ± 42.6 dB/m, p = 0.052 vs. placebo: -10.72 ± 46.6 dB/m, p = 0.29) and fibrosis levels (probiotics: -0.25 ± 1.77 kPa, p = 0.55 vs. placebo: -0.62 ± 2.37 kPa, p = 0.23) as measured by transient elastography. Likewise, no significant changes were found for both groups for the following parameters: LiverFAST analysis (steatosis, fibrosis and inflammation scores), alanine aminotransferase, total cholesterol, triglycerides, and fasting glucose. In the immunohistochemistry (IHC) analysis, no significant expression changes were seen for CD4+ T lymphocytes in either group (probiotics: -0.33 ± 1.67, p = 0.35 vs. placebo: 0.35 ± 3.25, p = 0.63). However, significant reductions in the expression of CD8+ T lymphocytes (-7.0 ± 13.73, p = 0.04) and ZO-1 (Z-score = -2.86, p = 0.04) were found in the placebo group, but no significant changes in the probiotics group. In this pilot study, the use of probiotics did not result in any significant clinical improvement in NAFLD patients. However, at the microenvironment level (i.e., the small intestinal mucosa), probiotics seemed to be able to stabilize the mucosal immune function and to protect NAFLD patients against increased intestinal permeability. Therefore, probiotics might have a complementary role in treating NAFLD. Further studies with larger sample sizes, a longer duration, and different probiotic strains are needed to evaluate the real benefit of probiotics in NAFLD.


Assuntos
Bifidobacterium , Mucosa Intestinal , Intestino Delgado , Lactobacillus , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Probióticos/uso terapêutico , Adulto , Idoso , Linfócitos T CD8-Positivos/metabolismo , Método Duplo-Cego , Disbiose/tratamento farmacológico , Técnicas de Imagem por Elasticidade , Feminino , Microbioma Gastrointestinal , Humanos , Imunidade , Inflamação , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Intestino Delgado/imunologia , Intestino Delgado/patologia , Fígado/metabolismo , Cirrose Hepática , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/metabolismo , Permeabilidade , Projetos Piloto , Resultado do Tratamento
10.
Arch Microbiol ; 203(10): 6109-6118, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34553262

RESUMO

Bifidobacterium longum NCIM 5672 is a probiotic strain isolated from the Indian infant feces. The probiotic efficacy of Bifidobacteria is majorly affected by its acid tolerance. This study determined the probiotic properties and acid-tolerance mechanism of B. longum NCIM 5672 using whole-genome sequencing. The genome annotation is carried out using the RAST web server and NCBI PGAAP. The draft genome sequence of this strain, assembled in 63 contigs, consists of 22,46,978 base pairs, 1900 coding sequences and a GC content of 59.6%. The genome annotation revealed that seven candidate genes might be involved in regulating the acid tolerance of B. longum NCIM 5672. Furthermore, the presence of genes associated with immunomodulation and cell adhesion support the probiotic background of the strain. The analysis of candidate acid- tolerance-associated genes revealed three genes, argC, argH, and dapA, may play an essential role in high acid tolerance in B. longum NCIM 5672. The results of RT-qPCR supported this conclusion. Altogether, the results presented here supply an effective way to select acid-resistant strains for the food industry and provide new strategies to enhance this species' industrial applications and health-promoting properties.


Assuntos
Bifidobacterium longum , Probióticos , Bifidobacterium/genética , Bifidobacterium longum/genética , Fezes , Genoma Bacteriano/genética , Humanos
11.
Nutrients ; 13(8)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34444834

RESUMO

Accumulating evidence has revealed the critical roles of commensal microbes in cancer progression and recently several investigators have evaluated the therapeutic effectiveness of targeting the microbiota. This gut microbiota-related approach is especially attractive in the treatment of gastrointestinal cancers. Probiotics supplementation is a microbiota-targeted strategy that appears to improve treatment efficacy; Lactobacillus spp. and Bifidobacterium spp. are among the most commonly used probiotic agents. These bacteria seem to exert immunomodulatory effects, impacting on the immune system both locally and systemically. The gut microbiota are able to affect the efficiency of immunotherapy, mainly acting as inhibitors at immune checkpoints. The effects of immunotherapy may be modulated using traditional probiotic strains and/or next generation probiotics, such as Akkermansia municiphila. It is possible that probiotics might enhance the efficiency of immunotherapy based on PD-1/PD-L1 and CTLA-4 but more data are needed to confirm this speculation. Indeed, although there is experimental evidence for the efficacy of several strains, the health-promoting effects of numerous probiotics have not been demonstrated in human patients and furthermore the potential risks of these products, particularly in oncologic patients, are rarely mentioned.


Assuntos
Bifidobacterium , Microbioma Gastrointestinal/imunologia , Neoplasias Gastrointestinais/imunologia , Neoplasias Gastrointestinais/microbiologia , Lactobacillus , Akkermansia , Animais , Bactérias , Humanos , Sistema Imunitário , Imunomodulação , Probióticos/administração & dosagem
12.
Immunity ; 54(8): 1633-1635, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34380062

RESUMO

Immune-system maturation starts early in life, but studies investigating immune-system education in human infants remain scarce. In a recent issue of Cell, Henrick et al. study early gut microbiota and immune-system development in two infant cohorts. The authors describe that Bifidobacteria can use milk sugars to produce immunoregulatory compounds that induce immune tolerance and reduce intestinal inflammation.


Assuntos
Bifidobacterium/metabolismo , Sistema Imunitário/crescimento & desenvolvimento , Intestinos/imunologia , Intestinos/microbiologia , Leite Humano/química , Oligossacarídeos/metabolismo , Animais , Aleitamento Materno , Microbioma Gastrointestinal/fisiologia , Humanos , Tolerância Imunológica/imunologia , Fatores Imunológicos/química , Imunomodulação/imunologia , Lactente , Suécia , Estados Unidos
13.
Nutr Diabetes ; 11(1): 27, 2021 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-34389700

RESUMO

Trimethylamine-N-oxide (TMAO), a gut-microbiota-dependent metabolite generated from its dietary precursors such as choline, has been identified as an independent risk factor for atherosclerosis. Metformin is the most widely used drug for the treatment of type 2 diabetes (T2D), which has therapeutic effects on hyperglycemia accelerated atherosclerosis. A growing body of evidence suggest that metformin plays a therapeutic role by regulating the structure and metabolic function of gut microbiota. However, whether metformin has an impact on gut-microbiota-mediated TMAO production from choline remains obscure. In this study, the oral administration of metformin significantly reduced choline diet-increased serum TMAO in choline diet-fed C57BL/6J mice. The diversity analysis based on 16S rRNA gene sequencing of C57BL/6J mice fecal samples indicated that metformin markedly changed the gut-microbiota composition. Metformin was positively correlated with the enrichment of different intestinal bacteria such as Bifidobacterium and Akkermansia and a lower cutC (a choline utilization gene) abundance. Furthermore, the ex vivo and in vitro inhibitory effects of metformin on choline metabolism of TMA-producing bacteria were confirmed under anaerobic condition. The results suggested that metformin suppresses serum TMAO level by remodeling gut microbiota involved in TMA generation from choline.


Assuntos
Colina/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Metformina/farmacologia , Metilaminas/sangue , Akkermansia/metabolismo , Animais , Aterosclerose/metabolismo , Bifidobacterium/metabolismo , Colina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Dieta/métodos , Disbiose/metabolismo , Feminino , Humanos , Metilaminas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , RNA Ribossômico 16S
14.
J Vis Exp ; (173)2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34369921

RESUMO

Protein glycosylation is a diverse and common post-translational modification that has been associated with many important roles such as protein function, including protein folding, stability, enzymatic protection, and biological recognition. N-glycans attached to glycoproteins (such as lactoferrin, lactadherin, and immunoglobulins) cannot be digested by the host and reach the large intestine, where they are consumed by certain beneficial microbes. Therefore, they are considered next-generation prebiotic compounds that can selectively stimulate the gut microbiome's beneficial microorganisms. However, the isolation of these new classes of prebiotics requires novel enzymes. Here, we describe the recombinant production of novel glycosidases from different Bifidobacteria strains (isolated from infants, rabbits, chicken, and bumblebee) for improved N-glycan isolation from glycoproteins. The method presented in this study includes the following steps: molecular cloning of Bifidobacterial genes by an in vivo recombinational cloning strategy, control of transformation success, protein induction, and protein purification.


Assuntos
Bifidobacterium , Glicosídeo Hidrolases , Animais , Glicoproteínas/metabolismo , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Glicosilação , Polissacarídeos , Coelhos
15.
Int J Mol Sci ; 22(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34445166

RESUMO

Fucosylated carbohydrates and glycoproteins from human breast milk are essential for the development of the gut microbiota in early life because they are selectively metabolized by bifidobacteria. In this regard, α-L-fucosidases play a key role in this successful bifidobacterial colonization allowing the utilization of these substrates. Although a considerable number of α-L-fucosidases from bifidobacteria have been identified by computational analysis, only a few of them have been characterized. Hitherto, α-L-fucosidases are classified into three families: GH29, GH95, and GH151, based on their catalytic structure. However, bifidobacterial α-L-fucosidases belonging to a particular family show significant differences in their sequence. Because this fact could underlie distinct phylogenetic evolution, here extensive similarity searches and comparative analyses of the bifidobacterial α-L-fucosidases identified were carried out with the assistance of previous physicochemical studies available. This work reveals four and two paralogue bifidobacterial fucosidase groups within GH29 and GH95 families, respectively. Moreover, Bifidobacterium longum subsp. infantis species exhibited the greatest number of phylogenetic lineages in their fucosidases clustered in every family: GH29, GH95, and GH151. Since α-L-fucosidases phylogenetically descended from other glycosyl hydrolase families, we hypothesized that they could exhibit additional glycosidase activities other than fucosidase, raising the possibility of their application to transfucosylate substrates other than lactose in order to synthesis novel prebiotics.


Assuntos
Proteínas de Bactérias/metabolismo , Bifidobacterium/metabolismo , Fucose/metabolismo , alfa-L-Fucosidase/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Bifidobacterium/química , Bifidobacterium/genética , Metabolismo dos Carboidratos , Microbioma Gastrointestinal , Glicosilação , Humanos , Leite Humano/metabolismo , Filogenia , alfa-L-Fucosidase/química , alfa-L-Fucosidase/genética
16.
Food Res Int ; 147: 110488, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34399484

RESUMO

Flaxseed (Linum usitatissimum L.) is of interest as functional food because of the presence of compounds in its composition with potential health benefits, such as fatty acid omega-3, fiber, lignans and flavonoids. The bioactivity of lignans and flavonoids depends greatly on bacterial metabolism. Previously, lactobacilli and bifidobacteria strains were described to produce enterolignans and bioactive flavonoids (herbacetin, quercetin, quercetagetin, kaempferol, naringenin and eriodictyol) from flaxseed extracts and/or from secoisolariciresinol (SECO) in culture medium. In this work, cow's milk and soy beverage were supplemented with flaxseed extracts and fermented with selected lactobacilli and bifidobacteria strains. Lacticaseibacillus rhamnosus INIA P224, Limosilactobacillus mucosae INIA P508 and Lactiplantibacillus plantarum ESI 144 were capable of producing enterolactone (ENL) in both beverages supplemented with flaxseed, in addition to matairesinol and the flavonoids daidzein, genistein, glycitein, quercetin, naringenin, kaempferol and eriodictyol. On the other hand, Bifidobacterium breve INIA P367, Bifidobacterium pseudocatenulatum INIA P815 and Bifidobacterium pseudocatenulatum INIA P946 were able to produce quercetin, quercetagetin and high concentrations of herbacetin and SECO, in addition to pinoresinol, matairesinol, daidzein, genistein, naringenin, kaempferol and eriodictyol. The co-incubation of Lacticaseibacillus paracasei INIA P74 and Ligilactobacillus salivarius INIA P183 with Lactococcus lactis MG1363 harboring the food grade vector pLEB590.gly913, facilitated the production of ENL in soy beverage enriched with flaxseed. In this work, it is demonstrated how lactobacilli and bifidobacteria strains can improve the nutritional properties of flaxseed-enriched beverages, providing metabolites of great interest for human health.


Assuntos
Linho , Lignanas , Animais , Bebidas , Bifidobacterium , Bovinos , Flavonoides , Humanos , Lactobacillus , Lignanas/análise
17.
Niger J Clin Pract ; 24(8): 1133-1137, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34397020

RESUMO

Aims: To investigate alteration of intestinal microflora in uremia patients with or without blood purification treatments. Methods: The present study included a total of 109 adult patients who were administered in our hospital during 2014 August to 2015 December, 85 cases had already received hemodialysis treatment and 24 cases had not received any renal transplantation treatments. Serum levels of hemoglobin, albumin, creatinine, hypersensitive C reactive protein, and cystatin C, as well as blood urea nitrogen and estimated glomerular filtration rate were determined. 16S rRNA sequencing was conducted to determine the levels of Bifidobacterium, Lactobacillus acidophilus, Escherichia coli, and Enterococcus faecalis. Results: The hemoglobin level in the hemodialysis group was significantly higher than that of the non-hemodialysis patients. The levels of Bifidobacterium and Lactobacillus acidophilus were significantly lower while the levels of Escherichia coli and Enterococcus faecalis were significantly higher in both of the patient groups compared with the healthy control. In all treatment groups, levels of Bifidobacterium and Lactobacillus acidophilus were significantly higher and levels of Escherichia coli and Enterococcus faecalis were significantly lower compared with the non-blood purification treatment group. Conclusions: The intestinal microflora might be influenced by uremia and might also be affected by blood purification treatments.


Assuntos
Microbioma Gastrointestinal , Uremia , Adulto , Bifidobacterium , Humanos , Lactobacillus acidophilus , RNA Ribossômico 16S , Uremia/terapia
18.
Biomolecules ; 11(8)2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34439760

RESUMO

BACKGROUND: Accumulating evidence indicates that the gut microbiota can synthesize neurotransmitters as well as impact host-derived neurotransmitter levels. In the past, it has been challenging to decipher which microbes influence neurotransmitters due to the complexity of the gut microbiota. METHODS: To address whether a single microbe, Bifidobacterium dentium, could regulate important neurotransmitters, we examined Bifidobacteria genomes and explored neurotransmitter pathways in secreted cell-free supernatant using LC-MS/MS. To determine if B. dentium could impact neurotransmitters in vivo, we mono-associated germ-free mice with B. dentium ATCC 27678 and examined fecal and brain neurotransmitter concentrations. RESULTS: We found that B. dentium possessed the enzymatic machinery to generate γ-aminobutyric acid (GABA) from glutamate, glutamine, and succinate. Consistent with the genome analysis, we found that B. dentium secreted GABA in a fully defined microbial media and elevated fecal GABA in B. dentium mono-associated mice compared to germ-free controls. We also examined the tyrosine/dopamine pathway and found that B. dentium could synthesize tyrosine, but could not generate L-dopa, dopamine, norepinephrine, or epinephrine. In vivo, we found that B. dentium mono-associated mice had elevated levels of tyrosine in the feces and brain. CONCLUSIONS: These data indicate that B. dentium can contribute to in vivo neurotransmitter regulation.


Assuntos
Bifidobacterium/metabolismo , Neurotransmissores/metabolismo , Animais , Infecções por Bifidobacteriales/metabolismo , Encéfalo/metabolismo , Calibragem , Cromatografia Líquida , Microbioma Gastrointestinal , Genoma , Intestinos/patologia , Masculino , Camundongos , Microbiota , Espectrometria de Massas em Tandem , Tirosina/metabolismo
19.
Microbiome ; 9(1): 151, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193290

RESUMO

BACKGROUND: Improving probiotic engraftment in the human gut requires a thorough understanding of the in vivo adaptive strategies of probiotics in diverse contexts. However, for most probiotic strains, these in vivo genetic processes are still poorly characterized. Here, we investigated the effects of gut selection pressures from human, mice, and zebrafish on the genetic stability of a candidate probiotic Lactiplantibacillus plantarum HNU082 (Lp082) as well as its ecological and evolutionary impacts on the indigenous gut microbiota using shotgun metagenomic sequencing in combination with isolate resequencing methods. RESULTS: We combined both metagenomics and isolate whole genome sequencing approaches to systematically study the gut-adaptive evolution of probiotic L. plantarum and the ecological and evolutionary changes of resident gut microbiomes in response to probiotic ingestion in multiple host species. Independent of host model, Lp082 colonized and adapted to the gut by acquiring highly consistent single-nucleotide mutations, which primarily modulated carbohydrate utilization and acid tolerance. We cultivated the probiotic mutants and validated that these gut-adapted mutations were genetically stable for at least 3 months and improved their fitness in vitro. In turn, resident gut microbial strains, especially competing strains with Lp082 (e.g., Bacteroides spp. and Bifidobacterium spp.), actively responded to Lp082 engraftment by accumulating 10-70 times more evolutionary changes than usual. Human gut microbiota exhibited a higher ecological and genetic stability than that of mice. CONCLUSIONS: Collectively, our results suggest a highly convergent adaptation strategy of Lp082 across three different host environments. In contrast, the evolutionary changes within the resident gut microbes in response to Lp082 were more divergent and host-specific; however, these changes were not associated with any adverse outcomes. This work lays a theoretical foundation for leveraging animal models for ex vivo engineering of probiotics to improve engraftment outcomes in humans. Video abstract.


Assuntos
Microbioma Gastrointestinal , Microbiota , Probióticos , Animais , Bifidobacterium , Humanos , Camundongos , Peixe-Zebra
20.
Cancer Sci ; 112(10): 4050-4063, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34289209

RESUMO

Astragalus polysaccharides (APS), the main effective component of Astragalus membranaceus, can inhibit tumor growth, but the underlying mechanisms remain unclear. Previous studies have suggested that APS can regulate the gut microenvironment, including the gut microbiota and fecal metabolites. In this work, our results showed that APS could control tumor growth in melanoma-bearing mice. It could reduce the number of myeloid-derived suppressor cells (MDSC), as well as the expression of MDSC-related molecule Arg-1 and cytokines IL-10 and TGF-ß, so that CD8+ T cells could kill tumor cells more effectively. However, while APS were administered with an antibiotic cocktail (ABX), MDSC could not be reduced, and the growth rate of tumors was accelerated. Consistent with the changes in MDSC, the serum levels of IL-6 and IL-1ß were lowest in the APS group. Meanwhile, we found that fecal suspension from mice in the APS group could also reduce the number of MDSC in tumor tissues. These results revealed that APS regulated the immune function in tumor-bearing mice through remodeling the gut microbiota. Next, we focused on the results of 16S rRNA, which showed that APS significantly regulated most microorganisms, such as Bifidobacterium pseudolongum, Lactobacillus johnsonii and Lactobacillus. According to the Spearman analysis, the changes in abundance of these microorganisms were related to the increase of metabolites like glutamate and creatine, which could control tumor growth. The present study demonstrates that APS attenuate the immunosuppressive activity of MDSC in melanoma-bearing mice by remodeling the gut microbiota and fecal metabolites. Our findings reveal the therapeutic potential of APS to control tumor growth.


Assuntos
Astrágalo (Planta)/química , Linfócitos T CD8-Positivos/imunologia , Microbioma Gastrointestinal/efeitos dos fármacos , Melanoma/tratamento farmacológico , Células Supressoras Mieloides/efeitos dos fármacos , Polissacarídeos/farmacologia , Animais , Antibacterianos/administração & dosagem , Arginase/efeitos dos fármacos , Arginase/metabolismo , Bifidobacterium/efeitos dos fármacos , Bifidobacterium/metabolismo , Combinação de Medicamentos , Transplante de Microbiota Fecal , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/imunologia , Microbioma Gastrointestinal/fisiologia , Tolerância Imunológica , Interleucina-10/metabolismo , Interleucina-1beta/sangue , Interleucina-6/sangue , Lactobacillus/efeitos dos fármacos , Masculino , Melanoma/imunologia , Melanoma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/metabolismo , RNA Ribossômico 16S/análise , Fator de Crescimento Transformador beta/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Microambiente Tumoral/imunologia
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