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2.
Cell Rep Med ; 4(9): 101190, 2023 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-37683651

RESUMEN

Research on gut microbiota has generally focused on fecal samples, representing luminal content of the large intestine. However, nutrient uptake is restricted to the small intestine. Abundant immune cell populations at this anatomical site combined with diminished mucus secretion and looser junctions (partly to allow for more efficient fluid and nutrient absorption) also results in intimate host-microbe interactions despite more rapid transit. It is thus crucial to dissect key differences in both ecology and physiology between small and large intestine to better leverage the immense potential of human gut microbiota imprinting, including probiotic engraftment at biological sensible niches. Here, we provide a detailed review unfolding how the physiological and anatomical differences between the small and large intestine affect gut microbiota composition, function, and plasticity. This information is key to understanding how gut microbiota manipulation, including probiotic administration, may strain-dependently transform host-microbe interactions at defined locations.


Asunto(s)
Colon , Probióticos , Humanos , Intestino Delgado , Transporte Biológico , Heces
3.
Gut Microbes ; 15(1): 2185034, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36919522

RESUMEN

Probiotics are used for both generally healthy consumers and in clinical settings. However, theoretical and proven adverse events from probiotic consumption exist. New probiotic strains and products, as well as expanding use of probiotics into vulnerable populations, warrants concise, and actionable recommendations on how to work toward their safe and effective use. The International Scientific Association for Probiotics and Prebiotics convened a meeting to discuss and produce evidence-based recommendations on potential acute and long-term risks, risks to vulnerable populations, the importance for probiotic product quality to match the needs of vulnerable populations, and the need for adverse event reporting related to probiotic use. The importance of whole genome sequencing, which enables determination of virulence, toxin, and antibiotic resistance genes, as well as clear assignment of species and strain identity, is emphasized. We present recommendations to guide the scientific and medical community on judging probiotic safety.


What is the context? Probiotics, available to healthy consumers as both dietary supplements and foods, are also used by some patient populations. The goal of this paper is to determine if any new factors have emerged that would impact current views about probiotic safety for both these populations.What is new? The authors conclude that established practices are sensibly addressing factors important to the safety of traditional probiotics used by the general population. They also make recommendations regarding emerging safety considerations. Probiotics targeted for patient populations should undergo stringent testing to meet quality standards appropriate for that population, preferably verified by an independent third party. The safety of probiotics derived from species without a history of safe use must be considered on a case-by-case basis. Research is needed to address some gaps, for example which best animal models to use for safety assessment of live microbes, the possibility of antibiotic resistance gene transfer via transformation, and potential impact of probiotic-induced changes in microbiomes, interactions with drugs, and probiotic colonization.What is the impact? Probiotics of sufficient quality for patient populations are being developed and should be used accordingly. Long-term safety assessments for probiotics should be consistent with, and not more stringent than, current regulatory requirements for biologic drugs, including fecal microbial transplants. Rigor in collecting and reporting data on adverse events is needed. The authors confirm the need for understanding the entire genetic makeup of a probiotic as a cornerstone for assessing its safety.


Asunto(s)
Microbioma Gastrointestinal , Probióticos , Antibacterianos/efectos adversos , Prebióticos , Probióticos/efectos adversos
4.
Sci Rep ; 12(1): 17591, 2022 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-36266398

RESUMEN

Live biotherapeutic products constitute an emerging therapeutic approach to prevent or treat inflammatory bowel diseases. Lactobacillus acidophilus is a constituent of the human microbiota with probiotic potential, that is illustrated by improvement of intestinal inflammation and antimicrobial activity against several pathogens. In this study, we evaluated the immunomodulatory properties of the L. acidophilus strain BIO5768 at steady state and upon acute inflammation. Supplementation of naïve mice with BIO5768 heightened the transcript level of some IL-17 target genes encoding for protein with microbicidal activity independently of NOD2 signaling. Of these, the BIO5768-induced expression of Angiogenin-4 was blunted in monocolonized mice that are deficient for the receptor of IL-17 (but not for NOD2). Interestingly, priming of bone marrow derived dendritic cells by BIO5768 enhanced their ability to support the secretion of IL-17 by CD4+ T cells. Equally of importance, the production of IL-22 by type 3 innate lymphoid cells is concomitantly heightened in response to BIO5768. When administered alone or in combination with Bifidobacterium animalis spp. lactis BIO5764 and Limosilactobacillus reuteri, BIO5768 was able to alleviate at least partially intestinal inflammation induced by Citrobacter rodentium infection. Furthermore, BIO5768 was also able to improve colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). In conclusion, we identify a new potential probiotic strain for the management of inflammatory bowel diseases, and provide some insights into its IL-17-dependent and independent mode of action.


Asunto(s)
Colitis , Inmunidad Innata , Enfermedades Inflamatorias del Intestino , Lactobacillus acidophilus , Probióticos , Animales , Ratones , Bifidobacterium animalis , Colitis/inducido químicamente , Colitis/terapia , Colitis/microbiología , Infecciones por Enterobacteriaceae/terapia , Inflamación , Enfermedades Inflamatorias del Intestino/terapia , Interleucina-17 , Linfocitos , Probióticos/farmacología , Probióticos/uso terapéutico , Ácido Trinitrobencenosulfónico/efectos adversos
5.
Adv Nutr ; 13(5): 1450-1461, 2022 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-35776947

RESUMEN

Humans often show variable responses to dietary, prebiotic, and probiotic interventions. Emerging evidence indicates that the gut microbiota is a key determinant for this population heterogeneity. Here, we provide an overview of some of the major computational and experimental tools being applied to critical questions of microbiota-mediated personalized nutrition and health. First, we discuss the latest advances in in silico modeling of the microbiota-nutrition-health axis, including the application of statistical, mechanistic, and hybrid artificial intelligence models. Second, we address high-throughput in vitro techniques for assessing interindividual heterogeneity, from ex vivo batch culturing of stool and continuous culturing in anaerobic bioreactors, to more sophisticated organ-on-a-chip models that integrate both host and microbial compartments. Third, we explore in vivo approaches for better understanding of personalized, microbiota-mediated responses to diet, prebiotics, and probiotics, from nonhuman animal models and human observational studies, to human feeding trials and crossover interventions. We highlight examples of existing, consumer-facing precision nutrition platforms that are currently leveraging the gut microbiota. Furthermore, we discuss how the integration of a broader set of the tools and techniques described in this piece can generate the data necessary to support a greater diversity of precision nutrition strategies. Finally, we present a vision of a precision nutrition and healthcare future, which leverages the gut microbiota to design effective, individual-specific interventions.


Asunto(s)
Microbioma Gastrointestinal , Probióticos , Animales , Inteligencia Artificial , Dieta , Humanos , Prebióticos
6.
Cell Mol Life Sci ; 79(2): 80, 2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-35044528

RESUMEN

The gut and brain link via various metabolic and signalling pathways, each with the potential to influence mental, brain and cognitive health. Over the past decade, the involvement of the gut microbiota in gut-brain communication has become the focus of increased scientific interest, establishing the microbiota-gut-brain axis as a field of research. There is a growing number of association studies exploring the gut microbiota's possible role in memory, learning, anxiety, stress, neurodevelopmental and neurodegenerative disorders. Consequently, attention is now turning to how the microbiota can become the target of nutritional and therapeutic strategies for improved brain health and well-being. However, while such strategies that target the gut microbiota to influence brain health and function are currently under development with varying levels of success, still very little is yet known about the triggers and mechanisms underlying the gut microbiota's apparent influence on cognitive or brain function and most evidence comes from pre-clinical studies rather than well controlled clinical trials/investigations. Filling the knowledge gaps requires establishing a standardised methodology for human studies, including strong guidance for specific focus areas of the microbiota-gut-brain axis, the need for more extensive biological sample analyses, and identification of relevant biomarkers. Other urgent requirements are new advanced models for in vitro and in vivo studies of relevant mechanisms, and a greater focus on omics technologies with supporting bioinformatics resources (training, tools) to efficiently translate study findings, as well as the identification of relevant targets in study populations. The key to building a validated evidence base rely on increasing knowledge sharing and multi-disciplinary collaborations, along with continued public-private funding support. This will allow microbiota-gut-brain axis research to move to its next phase so we can identify realistic opportunities to modulate the microbiota for better brain health.


Asunto(s)
Eje Cerebro-Intestino , Encéfalo/fisiología , Microbioma Gastrointestinal , Animales , Encéfalo/fisiopatología , Cognición , Humanos , Redes y Vías Metabólicas , Transducción de Señal
7.
Eur J Med Res ; 26(1): 40, 2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-33947466

RESUMEN

Traditional probiotics are increasingly being used in a medical context. The use of these products as drugs is considerably different from the traditional use as food or food supplements, as, obviously, the target population is different (diseased versus healthy or at risk population). Besides the target population, also the regulatory context is different, mainly with respect to production, administration regime and type of clinical studies required. In this paper we will, besides the regulatory differences, focus on aspects that may impact the efficacy of a live biotherapeutic product (drug), especially in a clinical setting. The impact of the dosage seems to depend on the strain and the application and may follow some rationale. In contrast, information on the impact of the time of administration or diet, is often still lacking. The matrix and the use of protective measures may clearly have an impact on the survival and efficacy of the strain.


Asunto(s)
Productos Biológicos/uso terapéutico , Suplementos Dietéticos , Probióticos/uso terapéutico , Humanos , Resultado del Tratamiento
8.
Nutrients ; 13(3)2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33668212

RESUMEN

Since alterations of the gut microbiota have been shown to play a major role in obesity, probiotics have attracted attention. Our aim was to identify probiotic candidates for the management of obesity using a combination of in vitro and in vivo approaches. We evaluated in vitro the ability of 23 strains to limit lipid accumulation in adipocytes and to enhance the secretion of satiety-promoting gut peptide in enteroendocrine cells. Following the in vitro screening, selected strains were further investigated in vivo, single, or as mixtures, using a murine model of diet-induced obesity. Strain Bifidobacterium longum PI10 administrated alone and the mixture of B. animalis subsp. lactis LA804 and Lactobacillus gasseri LA806 limited body weight gain and reduced obesity-associated metabolic dysfunction and inflammation. These protective effects were associated with changes in the hypothalamic gene expression of leptin and leptin receptor as well as with changes in the composition of gut microbiota and the profile of bile acids. This study provides crucial clues to identify new potential probiotics as effective therapeutic approaches in the management of obesity, while also providing some insights into their mechanisms of action.


Asunto(s)
Adipocitos/microbiología , Células Enteroendocrinas/microbiología , Microbioma Gastrointestinal/fisiología , Obesidad/microbiología , Probióticos/farmacología , Animales , Ácidos y Sales Biliares/metabolismo , Dieta/efectos adversos , Modelos Animales de Enfermedad , Hormonas Gastrointestinales/metabolismo , Hipotálamo/metabolismo , Leptina/metabolismo , Ratones , Obesidad/etiología , Manejo de la Obesidad/métodos , Receptores de Leptina/metabolismo , Aumento de Peso/fisiología
9.
Exp Mol Med ; 52(9): 1397-1406, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32908212

RESUMEN

Probiotics have been defined as "Live microorganisms that when administered in adequate amounts confer a health benefit on the host". This definition covers a wide range of applications, target populations and (combinations of) microorganisms. Improved knowledge on the importance of the microbiota in terms of health and disease has further diversified the potential scope of a probiotic intervention, whether intended to reach the market as a food, a food supplement or a drug, depending on the intended use. However, the increased interest in the clinical application of probiotics may require specific attention given their administration in a diseased population. In addition to safety, the impact of the type of product, in terms of quality, production method and, e.g., the acceptance of side effects, is now part of the current regulatory constraints for developers. In the European Union, foods are regulated by the European Food Safety Authority and drugs by the European Medicines Agency; in the United States, the Food and Drug Administration (FDA) deals with both categories. More recently, the FDA has defined a new "live biotherapeutic products" (LBP) category, clarifying pharmaceutical expectations. Since 2019, the quality requirements for this category of drug products have also been clarified by the European Pharmacopoeia (Ph. Eur.). Similar to all products intended to prevent or treat diseases, LBPs will have to be registered as medicinal products to reach the market in the US and in Europe. In this area, regulatory authorities and the pharmaceutical industry will routinely use guidelines of the "International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use" (ICH). Although ICH guidelines are not legally binding, they provide very important recommendations, recognized by almost all drug authorities in the world. In this review, we discuss some aspects of this regulatory framework, especially focusing on products with an intended use in a diseased or vulnerable target population.


Asunto(s)
Productos Biológicos/farmacología , Productos Biológicos/uso terapéutico , Terapia Biológica/métodos , Animales , Productos Biológicos/normas , Terapia Biológica/normas , Desarrollo de Medicamentos/legislación & jurisprudencia , Desarrollo de Medicamentos/métodos , Desarrollo de Medicamentos/normas , Guías como Asunto , Humanos , Legislación de Medicamentos , Probióticos/farmacología , Probióticos/normas , Probióticos/uso terapéutico
10.
Front Microbiol ; 11: 1662, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32793153

RESUMEN

Still relevant after 19 years, the FAO/WHO definition of probiotics can be translated into four simple and pragmatic criteria allowing one to conclude if specific strains of microorganisms qualify as a probiotic for use in foods and dietary supplements. Probiotic strains must be (i) sufficiently characterized; (ii) safe for the intended use; (iii) supported by at least one positive human clinical trial conducted according to generally accepted scientific standards or as per recommendations and provisions of local/national authorities when applicable; and (iv) alive in the product at an efficacious dose throughout shelf life. We provide clarity and detail how each of these four criteria can be assessed. The wide adoption of these criteria is necessary to ensure the proper use of the word probiotic in scientific publications, on product labels, and in communications with regulators and the general public.

11.
Front Med (Lausanne) ; 7: 237, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32637416

RESUMEN

Recent developments in the understanding of the relationship between the microbiota and its host have provided evidence regarding the therapeutic potential of selected microorganisms to prevent or treat disease. According to Directive 2001/83/EC, in the European Union (EU), any product intended to prevent or treat disease is defined as a medicinal product and requires a marketing authorization by competent authorities prior to commercialization. Even if the pharmaceutical regulatory framework is harmonized at the EU level, obtaining marketing authorisations for medicinal products remains very challenging for Live Biotherapeutic Products (LBPs). Compared to other medicinal products currently on the market, safety assessment of LBPs represents a real challenge because of their specific characteristics and mode of action. Indeed, LBPs are not intended to reach the systemic circulation targeting distant organs, tissues, or receptors, but rather exert their effect through direct interactions with the complex native microbiota and/or the modulation of complex host-microbiota relation, indirectly leading to distant biological effects within the host. Hence, developers must rely on a thorough risk analysis, and pharmaceutical guidelines for other biological products should be taken into account in order to design relevant non-clinical and clinical development programmes. Here we aim at providing a roadmap for a risk analysis that takes into account the specificities of LBPs. We describe the different risks associated with these products and their interactions with the patient. Then, from that risk assessment, we propose solutions to design non-clinical programmes and First in Human (FIH) early clinical trials appropriate to assess LBP safety.

12.
Int J Syst Evol Microbiol ; 70(4): 2782-2858, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32293557

RESUMEN

The genus Lactobacillus comprises 261 species (at March 2020) that are extremely diverse at phenotypic, ecological and genotypic levels. This study evaluated the taxonomy of Lactobacillaceae and Leuconostocaceae on the basis of whole genome sequences. Parameters that were evaluated included core genome phylogeny, (conserved) pairwise average amino acid identity, clade-specific signature genes, physiological criteria and the ecology of the organisms. Based on this polyphasic approach, we propose reclassification of the genus Lactobacillus into 25 genera including the emended genus Lactobacillus, which includes host-adapted organisms that have been referred to as the Lactobacillus delbrueckii group, Paralactobacillus and 23 novel genera for which the names Holzapfelia, Amylolactobacillus, Bombilactobacillus, Companilactobacillus, Lapidilactobacillus, Agrilactobacillus, Schleiferilactobacillus, Loigolactobacilus, Lacticaseibacillus, Latilactobacillus, Dellaglioa, Liquorilactobacillus, Ligilactobacillus, Lactiplantibacillus, Furfurilactobacillus, Paucilactobacillus, Limosilactobacillus, Fructilactobacillus, Acetilactobacillus, Apilactobacillus, Levilactobacillus, Secundilactobacillus and Lentilactobacillus are proposed. We also propose to emend the description of the family Lactobacillaceae to include all genera that were previously included in families Lactobacillaceae and Leuconostocaceae. The generic term 'lactobacilli' will remain useful to designate all organisms that were classified as Lactobacillaceae until 2020. This reclassification reflects the phylogenetic position of the micro-organisms, and groups lactobacilli into robust clades with shared ecological and metabolic properties, as exemplified for the emended genus Lactobacillus encompassing species adapted to vertebrates (such as Lactobacillus delbrueckii, Lactobacillus iners, Lactobacillus crispatus, Lactobacillus jensensii, Lactobacillus johnsonii and Lactobacillus acidophilus) or invertebrates (such as Lactobacillus apis and Lactobacillus bombicola).


Asunto(s)
Lactobacillaceae/clasificación , Lactobacillus/clasificación , Leuconostocaceae/clasificación , Filogenia , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Análisis de Secuencia de ADN
13.
Sci Rep ; 10(1): 5345, 2020 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-32210304

RESUMEN

Crohn's disease is linked to a decreased diversity in gut microbiota composition as a potential consequence of an impaired anti-microbial response and an altered polarization of T helper cells. Here, we evaluated the immunomodulatory properties of two potential probiotic strains, namely a Bifidobacterium animalis spp. lactis Bl 5764 and a Lactobacillus reuteri Lr 5454 strains. Both strains improved colitis triggered by either 2,4,6-trinitrobenzenesulfonic acid (TNBS) or Citrobacter rodentium infection in mice. Training of dendritic cells (DC) with Lr 5454 efficiently triggered IL-22 secretion and regulatory T cells induction in vitro, while IL-17A production by CD4+ T lymphocytes was stronger when cultured with DCs that were primed with Bl 5764. This strain was sufficient for significantly inducing expression of antimicrobial peptides in vivo through the Crohn's disease predisposing gene encoding for the nucleotide-binding oligomerization domain, containing protein 2 (NOD2). In contrast, NOD2 was dispensable for the impact on antimicrobial peptide expression in mice that were monocolonized with Lr 5454. In conclusion, our work highlights a differential mode of action of two potential probiotic strains that protect mice against colitis, providing the rational for a personalized supportive preventive therapy by probiotics for individuals that are genetically predisposed to Crohn's disease.


Asunto(s)
Bifidobacterium animalis , Colitis/microbiología , Colitis/terapia , Células Dendríticas/fisiología , Limosilactobacillus reuteri , Probióticos/farmacología , Animales , Antiinflamatorios no Esteroideos/farmacología , Citrobacter rodentium/patogenicidad , Colitis/inducido químicamente , Colitis/patología , Modelos Animales de Enfermedad , Infecciones por Enterobacteriaceae/microbiología , Femenino , Microbioma Gastrointestinal , Vida Libre de Gérmenes , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Asociadas a Pancreatitis/genética , Linfocitos T Colaboradores-Inductores/fisiología , Linfocitos T Reguladores/fisiología , Ácido Trinitrobencenosulfónico/toxicidad
14.
Cell Physiol Biochem ; 53(5): 774-793, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31647207

RESUMEN

BACKGROUND/AIMS: Deregulation of the complex interaction among host genetics, gut microbiota and environmental factors on one hand and aberrant immune responses on the other hand, are known to be associated with the development of inflammatory bowel disease. Recent studies provided strong evidence that autophagy plays a key role in the etiology of Crohn's disease (CD). Probiotics may exhibit many therapeutic properties, including anti-inflammatory abilities. While successful results have been obtained in ulcerative colitis patients, probiotics remain inefficient in CD for unknown reason. It remains therefore important to better understand their molecular mechanisms of action. METHODS: The activation of autophagy was examined by stimulating bone marrow-derived dendritic cells by the bacteria, followed by confocal microscopy and western blot analysis. The impact of blocking in vitro autophagy was performed in peripheral blood mononuclear cells using 3-methyl adenine or bafilomycin followed by cytokine secretion measurement by ELISA. The role of autophagy in the anti-inflammatory capacities of the bacterial strains was evaluated in vivo using an acute trinitrobenzene sulfonic acid-induced murine model of colitis. The impact of BMDC was evaluated by adoptive transfer, notably using bone marrow cells derived from autophagy-related 16-like 1-deficient mice. RESULTS: We showed that selected lactobacilli and bifidobacteria are able to induce autophagy activation in BMDCs. Blocking in vitro autophagy abolished the capacity of the strains to induce the release of the anti-inflammatory cytokine interleukin-10, while it exacerbated the secretion of the pro-inflammatory cytokine interleukin-1ß. We confirmed in the TNBS-induced mouse model of colitis that autophagy is involved in the protective capacity of these selected strains, and showed that dendritic cells are involved in this process. CONCLUSION: We propose autophagy as a novel mechanism involved in the regulatory capacities of probiotics.


Asunto(s)
Autofagia , Bifidobacterium/fisiología , Lactobacillus/fisiología , Adenina/análogos & derivados , Adenina/farmacología , Animales , Proteínas Relacionadas con la Autofagia , Células de la Médula Ósea/citología , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Quimiocinas/genética , Quimiocinas/metabolismo , Colitis/inducido químicamente , Colitis/microbiología , Colitis/patología , Citocinas/genética , Citocinas/metabolismo , Células Dendríticas/citología , Células Dendríticas/metabolismo , Células Dendríticas/microbiología , Femenino , Humanos , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/metabolismo , Macrólidos/farmacología , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados
15.
Data Brief ; 25: 104282, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31388525

RESUMEN

Lactobacillus delbrueckii subsp. lactis is employed in the production of various types of cheese. Here, we report the complete genome sequence of L. lactis ACA-DC 178 isolated from Greek Kasseri cheese. The chromosome of ACA-DC 178 contains 2,050,316 bp with a GC content of 49.6%. A total of 2,112 genes were identified in the genome sequence including 1,752 protein-coding genes, 239 putative pseudogenes, 94 tRNA and 27 rRNA genes. According to the COG annotation, about 80% of the protein-coding genes (1,417 proteins) were assigned to at least one functional category. Approximately the 1/3 of these proteins were distributed among three categories, namely replication, recombination and repair (category L: 10.6%), translation, ribosomal structure and biogenesis (category J: 7.5%) and amino acid transport and metabolism (category E: 7.2%). Fourteen integrated GIs with a total of 159 genes were found in ACA-DC 178 genome. Several of these genes encode proteins associated with exopolysaccharide biosynthesis, amino acid transport and subunits of restriction-modification systems. One large CRISPR array of 3,197 bp containing 52 spacers, several of which are identical to phage sequences having hosts in the genus Lactobacillus, was also identified. The annotated genome sequence of L. lactis ACA-DC 178 is deposited at the European Nucleotide Archive under the accession number LS991409. Raw reads are deposited in the Sequence Read Archive (SRR8866601-3).

17.
Front Microbiol ; 10: 2916, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31956321

RESUMEN

Streptococcus thermophilus is a major starter for the dairy industry with great economic importance. In this study we analyzed 23 fully sequenced genomes of S. thermophilus to highlight novel aspects of the evolution, biology and technological properties of this species. Pan/core genome analysis revealed that the species has an important number of conserved genes and that the pan genome is probably going to be closed soon. According to whole genome phylogeny and average nucleotide identity (ANI) analysis, most S. thermophilus strains were grouped in two major clusters (i.e., clusters A and B). More specifically, cluster A includes strains with chromosomes above 1.83 Mbp, while cluster B includes chromosomes below this threshold. This observation suggests that strains belonging to the two clusters may be differentiated by gene gain or gene loss events. Furthermore, certain strains of cluster A could be further subdivided in subgroups, i.e., subgroup I (ASCC 1275, DGCC 7710, KLDS SM, MN-BM-A02, and ND07), II (MN-BM-A01 and MN-ZLW-002), III (LMD-9 and SMQ-301), and IV (APC151 and ND03). In cluster B certain strains formed one distinct subgroup, i.e., subgroup I (CNRZ1066, CS8, EPS, and S9). Clusters and subgroups observed for S. thermophilus indicate the existence of lineages within the species, an observation which was further supported to a variable degree by the distribution and/or the architecture of several genomic traits. These would include exopolysaccharide (EPS) gene clusters, Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs)-CRISPR associated (Cas) systems, as well as restriction-modification (R-M) systems and genomic islands (GIs). Of note, the histidine biosynthetic cluster was found present in all cluster A strains (plus strain NCTC12958T) but was absent from all strains in cluster B. Other loci related to lactose/galactose catabolism and urea metabolism, aminopeptidases, the majority of amino acid and peptide transporters, as well as amino acid biosynthetic pathways were found to be conserved in all strains suggesting their central role for the species. Our study highlights the necessity of sequencing and analyzing more S. thermophilus complete genomes to further elucidate important aspects of strain diversity within this starter culture that may be related to its application in the dairy industry.

19.
Clin Nutr ESPEN ; 27: 59-65, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30144894

RESUMEN

BACKGROUND: A potential positive effect of probiotics in cystic fibrosis (CF) on fecal calprotectin (FCP), pulmonary exacerbations and weight has been described in small controlled trials. METHODS: A double-blind multicenter cross-over study (2 × 4 m) was performed looking at abdominal pain, nutritional status, pulmonary function, pulmonary exacerbation, FCP and lactulose/mannitol gut permeability test. Patients kept a diary with daily scoring of abdominal pain, stool frequency and consistency as well as treatment changes. RESULTS: 31 CF patients entered the study of which 25 finished it. At start patients aged 9.3yrs (6.9-12.2), had a median BMI z-score of -0.5 (-1.5-0.08), height z-score of -0.4 (-1.1-0.05) and FEV1% of 100% (87.2-106.6). Median FCP at start was 61 µg/g (17-108) and gut permeability 0.079 (0.051-0.122). No significant changes were observed in the clinical parameters (BMI, FEV1%, abdominal pain, exacerbations). Despite being frequently abnormal (17/28 (61%) >50 mg/kg), FCP did not change significantly with probiotics. The proportion of patients with normal permeability was 8% during placebo and 32% during probiotic treatment (p = 0.031). FCP correlated to BMI z-score (p = 0.043) and gut permeability to abdominal pain (p = 0.015). The microbiome revealed a high predominance of Actinobacteria and Proteobacteriae. Probiotic supplementation did not result in a shift at the phylum nor at phylogenetic level. CONCLUSION: Normalization of gut permeability was observed in 13% of patients during probiotic treatment. However, none of the previously described effects could be confirmed.


Asunto(s)
Dolor Abdominal/microbiología , Fibrosis Quística/microbiología , Heces/microbiología , Complejo de Antígeno L1 de Leucocito/metabolismo , Probióticos/uso terapéutico , Dolor Abdominal/dietoterapia , Niño , Estudios Cruzados , Fibrosis Quística/complicaciones , Fibrosis Quística/fisiopatología , Método Doble Ciego , Femenino , Microbioma Gastrointestinal , Humanos , Masculino , Proyectos Piloto , Resultado del Tratamiento
20.
Front Microbiol ; 9: 1244, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29942291

RESUMEN

Lactobacillus acidipiscis belongs to the Lactobacillus salivarius clade and it is found in a variety of fermented foods. Strain ACA-DC 1533 was isolated from traditional Greek Kopanisti cheese and among the available L. acidipiscis genomes it is the only one with a fully sequenced chromosome. L. acidipiscis strains exhibited a high degree of conservation at the genome level. Investigation of the distribution of prophages and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs) among the three strains suggests the potential existence of lineages within the species. Based on the presence/absence patterns of these genomic traits, strain ACA-DC 1533 seems to be more related to strain JCM 10692T than strain KCTC 13900. Interestingly, strains ACA-DC 1533 and JCM 10692T which lack CRISPRs, carry two similar prophages. In contrast, strain KCTC 13900 seems to have acquired immunity to these prophages according to the sequences of spacers in its CRISPRs. Nonetheless, strain KCTC 13900 has a prophage that is absent from strains ACA-DC 1533 and JCM 10692T. Furthermore, comparative genomic analysis was performed among L. acidipiscis ACA-DC 1533, L. salivarius UCC118 and Lactobacillus ruminis ATCC 27782. The chromosomes of the three species lack long-range synteny. Important differences were also determined in the number of glycobiome related proteins, proteolytic enzymes, transporters, insertion sequences and regulatory proteins. Moreover, no obvious genomic traits supporting a probiotic potential of L. acidipiscis ACA-DC 1533 were detected when compared to the probiotic L. salivarius UCC118. However, the existence of more than one glycine-betaine transporter within the genome of ACA-DC 1533 may explain the ability of L. acidipiscis to grow in fermented foods containing high salt concentrations. Finally, in silico analysis of the L. acidipiscis ACA-DC 1533 genome revealed pathways that could underpin the production of major volatile compounds during the catabolism of amino acids that may contribute to the typical piquant flavors of Kopanisti cheese.

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