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This work reports on the first described aerotolerant Bifidobacterium bifidum strain, Bifidobacterium bifidum IPLA60003, which has the ability to form colonies on the surface of agar plates under aerobic conditions, a weird phenotype that to our knowledge has never been observed in B. bifidum. The strain IPLA60003 was generated after random UV mutagenesis from an intestinal isolate. It incorporates 26 single nucleotide polymorphisms that activate the expression of native oxidative-defense mechanisms such as the alkyl hydroxyperoxide reductase, the glycolytic pathway and several genes coding for enzymes involved in redox reactions. In the present work, we discuss the molecular mechanisms underlying the aerotolerance phenotype of B. bifidum IPLA60003, which will open new strategies for the selection and inclusion of probiotic gut strains and next generation probiotics into functional foods.

Since its development in the 1960s, flow cytometry (FCM) was quickly revealed a powerful tool to analyse cell populations in medical studies, yet, for many years, was almost exclusively used to analyse eukaryotic cells. Instrument and methodological limitations to distinguish genuine bacterial signals from the background, among other limitations, have hampered FCM applications in bacteriology. In recent years, thanks to the continuous development of FCM instruments and methods with a higher discriminatory capacity to detect low-size particles, FCM has emerged as an appealing technique to advance the study of microbes, with important applications in research, clinical and industrial settings. The capacity to rapidly enumerate and classify individual bacterial cells based on viability facilitates the monitoring of bacterial presence in foodstuffs or clinical samples, reducing the time needed to detect contamination or infectious processes. Besides, FCM has stood out as a valuable tool to advance the study of complex microbial communities, or microbiomes, that are very relevant in the context of human health, as well as to understand the interaction of bacterial and host cells. This review highlights current developments in, and future applications of, FCM in bacteriology, with a focus on those related to food and clinical microbiology.

The pks island is one of the most prevalent pathogenicity islands among the Escherichia coli strains that colonize the colon of colorectal carcinoma (CRC) patients. This pathogenic island encodes the production of a nonribosomal polyketide-peptide named colibactin, which induces double-strand breaks in DNA molecules. Detection or even depletion of this pks-producing bacteria could help to understand the role of these strains in the context of CRC. In this work, we performed a large-scale in silico screening of the pks cluster in more than 6,000 isolates of E. coli. The results obtained reveal that not all the pks-detected strains could produce a functional genotoxin and, using antibodies against pks-specific peptides from surface cell proteins, a methodology for detection and depletion of pks+ bacteria in gut microbiotas was proposed. With our method, we were able to deplete a human gut microbiota of this pks+ strains, opening the door to strain-directed microbiota modification and intervention studies that allow us to understand the relation between these genotoxic strains and some gastrointestinal diseases. IMPORTANCE The human gut microbiome has also been hypothesized to play a crucial role in the development and progression of colorectal carcinoma (CRC). Between the microorganisms of this community, the Escherichia coli strains carrying the pks genomic island were shown to be capable of promoting colon tumorigenesis in a colorectal cancer mouse model, and their presence seems to be directly related to a distinct mutational signature in patients suffering CRC. This work proposes a novel method for the detection and depletion of pks-carrying bacteria in human gut microbiotas. In contrast to methods based on probes, this methodology allows the depletion of low-abundance bacterial strains maintaining the viability of both targeted and non-targeted fractions of the microbiota, allowing the study of the contribution of these pks-carrying strains to different diseases

[ES] La presente invención se relaciona con un microorganismo del género Bifidobacterium spp. que comprende un promotor que comprende la secuencia GAAAGGA (SEQ ID NO: 1) a una distancia de entre 12 y 31 nucleótidos del codón de inicio responsable de la transcripción de un gen, en donde dicho microorganismo es aerotolerante y pertenece a la especie B. bifidum. La presente invención también se relaciona con la composición que comprende dicho microorganismo y los usos del mismo tanto en salud debido a sus propiedades beneficiosas para la salud como en la fabricación de productos lácteos fermentados., [EN] The present invention is related to a microorganism of the genus Bifidobacterium spp. which includes a promoter that comprises the Gaaagga sequence (SEQ ID no: 1) at a distance between 12 and 31 nucleotides of the start -up codon responsible for the transcription of a gene, where said microorganism is aerotolerant and belongs to species B. bifidum. The present invention is also related to the composition that includes this microorganism and the uses of the same in health due to its beneficial health properties and in the manufacture of fermented dairy products.

[EN] The consumption of fermented vegetables is widespread throughout the world and represents an important component of the human diet with considerable contribution to the food supply for a world popula-tion in continuous growth. Many of the fermented vegetables share a general process which requires salting and acidification steps. Among the microorganisms responsible for fermentation, lactic acid bacteria are the most relevant with important organoleptic, quality and safety benefits. This review deals with the microbial ecology of fermented vegetables focusing on the biodiversity of lactic acid bacteria, the most important molecular tech-niques used for their identification and genotyping, their importance for the formation of biofilms as well as their use as starter cultures for obtaining high-quality and safe vegetable products, [ES] El consumo de vegetales fermenta-dos está muy extendido en el mundo y representa un componente importante de la dieta humana con un apoyo considerable a la cadena alimentaria para una población mundial en continuo crecimiento. Muchos de los vege-tales fermentados comparten un proceso general, que requiere una puesta en salmuera y acidificación. Entre los microorganismos responsables de la fermentación, las bacterias del ácido láctico son las más relevantes con una importante influencia sobre aspectos organolépticos, de calidad y seguridad del producto final. Esta revisión trata sobre la ecología microbiana de los vegetales fermentados, prestando especial atención a la biodiversidad de las bacterias del ácido láctico, las técnicas moleculares más importantes utilizadas para su identificación y genotipado, su importancia para la formación de biofilms y su uso como cultivos iniciadores multifuncionales para la obtención de productos vegetales de alta calidad y seguridad.

This work supports the massive presence of potential immunomodulatory peptides in the human gut metaproteome. These peptides were identified through the MAHMI database as potentially anti-inflammatory, and sixteen of them synthesized for characterize their mechanism of action. From them, peptide HM14 was encrypted in an extracellular protein produced by Bifidobacterium longum, a common member of the human microbiota, and displayed the highest anti-inflammatory capability. Molecular mechanism of action of HM14 pointed to a specific interaction between this immunomodulatory peptide and antigen presenting cells, which resulted in a higher formation of iTreg cells. Moreover, HM14 was effective in decreasing pro-inflammatory parameters in PBMCs isolated from a cohort of Crohn’s patients. Finally, non-targeted metabolomics confirmed the ability of HM14 to modulate the metabolic activity of PBMCs to fulfil its energy and biosynthetic requirements. Overall, our combined in silico/multiomics approach supports the human gut metaproteome as a source for immunomodulatory peptides.

COVID-2019 has progressed in around 10-15% of patients to an acute respiratory distress syndrome characterized by extensive pulmonary inflammation and elevated production of pro-inflammatory cytokines. Neutrophil activation seems to be crucial in the initiation and perpetuation of this exacerbated lung inflammation. However, the precise mechanisms by which this activation occurs remain yet elusive. To this end, this in silico study tried to identify potential proinflammatory inducing peptides (PIPs) produced by the action of the elastase released in neutrophil-extracellular traps over SARS-CoV-2 particles. We found nine potential PIPs exclusive from the SARS-CoV-2, showing homology against T cell recognition epitopes. Moreover, 78 percent of these exclusive PIPs were found produced by the enzymatic cleavage on the spike glycoproteins, suggesting that high PIP concentrations might be released following SARS-CoV-2 huge replication rate. Therefore, these PIPs might play a role in the exacerbated inflammatory response observed in some patients.

[Background] Several independent studies have addressed the beneficial role of lactic acid bacteria over different cancer types, both in vitro and in vivo. However, and to our knowledge, no molecular study has been performed to understand how this inhibitory effect may take place. [Methods] Different fractions from several lactic acid bacteria and bifidobacteria were obtained in order to test their effect over two well-known epithelial cell lines, Caco-2 and Ht29, using the RTCA device. Effect of this extract over cell cycle and the process of necrosis/apoptosis was checked by flow cytometry. Molecular mechanism of action was elucidated by RNASeq. Results: The most active fraction was obtained from Lactobacillus acidophilus, and RNASeq analysis revealed an activation of several detoxification/xenobiotic pathways in epithelial cells. Nuclear magnetic resonance revealed a quite complex extract with the presence of alanine and lactic acid. Alanine had no effect over proliferation but buffering of the extract suggested that some of the observed inhibitory effect was due to lactic acid. The antiproliferative effect was visible from 300 mg/L lactic acid, and 2,7 g/L were enough to induce complete culture death in Ht29 an Caco-2. [Conclusion] Although it remains to known the role of other compounds in the anti-proliferative effect of the L. acidophilus extract, we have shown for the first time that CaCo-2 and Ht29 cell lines are sensible to lactic acid concentrations lower than those observed for instance in yoghourt (9 g/L), suggesting that carcinogenic cells may be more sensitive to lactic acid than normal cells. Production of lactic acid in the colon is therefore a molecular mechanism of action by which lactic acid bacteria exert their beneficial role in the colon.

[Aim] The aim of this work was to evidence that the use of different stool collection strategies has a deep impact on the viability and diversity of the fecal microbiota that is recovered in the laboratory, notably if oxygen toxicity is not considered. This is particularly critical if the purpose of the sample is to envisage personalized biotherapeutic purposes, such as autologous fecal microbiota transplant or designing personalized biotherapeutics. [Methods] In order to analyze differences in the viability of fecal microbial populations during the whole delivery procedure, the same fecal specimens were sampled in conventional stool containers and GutAlive® devices, which minimize exposure of fecal microbiota to oxygen. Samples from five healthy donors were used and 150 differential colonies between the two devices were recovered. Differences included those associated to the two collection devices and individuals. All colonies were identified by 16S rRNA gene sequencing. Complete genomes of two extremely oxygen sensitive (EOS) bacteria recovered were sequenced with the Illumina MiSeq Sequencing System. [Results] Microbial diversity obtained was notably higher using GutAlive®. This device was able to maintain the viability of EOS species such as Akkermansia muciniphila, Faecalibacterium prausnitzii and a possible new member of the Clostridiales order. These obligate anaerobes were not recovered using the conventional stool container. Remarkably, GutAlive® allowed culturing and identifying an anaerobic isolate which may represent a new lineage within Clostridiales. This shows the importance of a personalized approach in microbiota-based therapies, as this novel isolate was recovered only from feces of one of the donors. [Conclusion] Using GutAlive® for stool sampling and transport allowed higher recovery of viable EOS bacteria by limiting oxygen exposure during the whole process. By standardizing the sampling and transport of the fecal specimens to the lab, GutAlive®

Durante los últimos diez años ha habido avances en la compresión de cómo la microbiota intestinal humana contribuye a nuestra salud y enfermedad. La microbiota humana, especialmente la microbiota intestinal, es considerada un “órgano esencial” debido a que las comunidades microbianas que colonizan todas las superficies de nuestro cuerpo nos proporcionan funciones metabólicas, inmunológicas y fisiológicas esenciales. Tras el nacimiento, nuestra microbiota intestinal alcanza su configuración final a la edad de 2 a 3 años con la introducción de alimentos sólidos, estableciéndose una comunidad de microorganismos dominada por anaerobios obligados. Después del nacimiento, alrededor de 100 especies bacterianas colonizan el intestino, aumentando hasta 103 en la edad adulta. Su composición evoluciona constantemente, dependiendo de factores internos y externos como la edad, la raza, la dieta, la colonización materna, así como la exposición a antibióticos y xenobióticos. Además, otros factores como el estrés o los tratamientos farmacológicos conducen a rápidos cambios en la composición de nuestra microbiota. La complejidad de la microbiota intestinal hace difícil deducir la contribución individual de una especie/cepa a un fenotipo, enfermedad o condición. Por ello, el desarrollo de métodos para la modificación dirigida de una microbiota, especialmente enfocada en eliminar de una comunidad microbiana una bacteria específica, podría ser útil para descifrar como una especie contribuye a una enfermedad o a un proceso fisiológico, inmunológico o metabólico. En este estudio presentamos una tecnología que, si bien no es desconocida, sí que es pionera en cuanto a su aplicación. Hemos utilizado un anticuerpo policlonal dirigido a la proteína A de la capa S de Lactobacillus acidophilus DSM20079T para conseguir detectarlo en un consorcio bacteriano compuesto de 8 especies representativas de la microbiota intestinal humana. Además, se ha realizado una depleción y enriquecimiento positivo

This work presents a novel in silico approach to the prediction and characterization of the glycolytic capacities of the beneficial intestinal bacterium Faecalibacterium prausnitzii. Available F. prausnitzii genomes were explored taking the glycolytic capacities of F. prausnitzii SL3/3 and F. prausnitzii L2-6 as reference. The comparison of the generated glycolytic profiles offered insights into the particular capabilities of F. prausnitzii SL3/3 and F. prausnitzii L2-6 as well as the potential of the rest of strains. Glycoside hydrolases were mostly detected in the pathways responsible for the starch and sucrose metabolism and the biosynthesis of secondary metabolites, but this analysis also identified some other potentially interesting, but still uncharacterized activities, such as several hexosyltransferases and some hydrolases. Gene neighborhood maps offered additional understanding of the genes coding for relevant glycoside hydrolases. Although information about the carbohydrate preferences of F. prausnitzii is scarce, the in silico metabolic predictions were consistent with previous knowledge about the impact of fermentable sugars on the growth promotion and metabolism of F. prausnitzii. So, while the predictions still need to be validated using culturing methods, the approach holds the potential to be reproduced and scaled to accommodate the analysis of other strains (or even families and genus) as well as other metabolic activities. This will allow the exploration of novel methodologies to design or obtain targeted probiotics for F. prausnitzii and other strains of interest.

The human gut microbiota is composed of the different microorganisms of our intestinal ecosystem. It has an important metabolic and nutritional role, and it is involved in the correct development of the gut and the maturation of our immune system. Currently, the application of fecal microbiota transplantation (FMT) has allowed us to establish causality in microbiome studies, and we know that microbiota can cure diseases or induce the appearance of disease symptoms, or even determine the success of some health treatments. But knowledge of the curative effects of feces has been documented many centuries ago. In the present article we want to make a brief review of the history of FMT, focusing on its effect on the human microbiome and its capacity to act on human physiology. We also want to place special emphasis on aspects that must be taken into account to translate microbiome research to medicine, related to safety, regulation and standardization of methods, as well as the importance of being able to predict the success of FMT.

Bile is a biological fluid synthesized in the liver, mainly constituted by bile acids and cholesterol, which functions as a biological detergent that emulsifies and solubilizes lipids, thereby playing an essential role in fat digestion. Besides, bile acids are important signaling molecules that regulate key functions at intestinal and systemic levels in the human body, affecting glucose and lipid metabolism, and immune homeostasis. Apart from this, due to their amphipathic nature, bile acids are toxic for bacterial cells and, thus, exert a strong selective pressure on the microbial populations inhabiting the human gut, decisively shaping the microbial profiles of our gut microbiota, which has been recognized as a metabolic organ playing a pivotal role in host health. Remarkably, bacteria in our gut also display a range of enzymatic activities capable of acting on bile acids and, to a lesser extent, cholesterol. These activities can have a direct impact on host physiology as they influence the composition of the intestinal and circulating bile acid pool in the host, affecting bile homeostasis. Given that bile acids are important signaling molecules in the human body, changes in the microbiota-residing bile biotransformation ability can significantly impact host physiology and health status. Elucidating ways to fine-tune microbiota-bile acids-host interplay are promising strategies to act on bile and cholesterol-related disorders. This manuscript summarizes the current knowledge on bile and cholesterol metabolism by intestinal bacteria, as well as its influence on host physiology, identifying knowledge gaps and opportunities to guide further advances in the field.

[Background] Some patients complain that eating lettuce, gives them gas and abdominal distention. Our aim was to determine to what extent the patients' assertion is sustained by evidence. [Methods] An in vitro study measured the amount of gas produced during the process of fermentation by a preparation of human colonic microbiota (n = 3) of predigested lettuce, as compared to beans, a high gas-releasing substrate, to meat, a low gas-releasing substrate, and to a nutrient-free negative control. A clinical study in patients complaining of abdominal distention after eating lettuce (n = 12) measured the amount of intestinal gas and the morphometric configuration of the abdominal cavity in abdominal CT scans during an episode of lettuce-induced distension as compared to basal conditions. [Key Results] Gas production by microbiota fermentation of lettuce in vitro was similar to that of meat (P =.44), lower than that of beans (by 78 ± 15%; P <.001) and higher than with the nutrient-free control (by 25 ± 19%; P =.05). Patients complaining of abdominal distension after eating lettuce exhibited an increase in girth (35 ± 3 mm larger than basal; P <.001) without significant increase in colonic gas content (39 ± 4 mL increase; P =.071); abdominal distension was related to a descent of the diaphragm (by 7 ± 3 mm; P =.027) with redistribution of normal abdominal contents. [Conclusion and Inferences] Lettuce is a low gas-releasing substrate for microbiota fermentation and lettuce-induced abdominal distension is produced by an uncoordinated activity of the abdominal walls. Correction of the somatic response might be more effective than the current dietary restriction strategy.

Stool collection devices minimizing the exposure of gut bacteria to oxygen are critical for the standardization of further microbiota-based studies, analysis and developments. The aim of this work was to evidence that keeping anaerobiosis has a deep impact on the viability and diversity of the fecal microbiota that is recovered in the laboratory. Recovering certain microbial populations, such as obligate anaerobic bacteria, is particularly critical if the purpose of the study is to envisage personalized therapeutic purposes, such as autologous Fecal Microbiota Transplant. In this study the same fecal specimens were sampled in conventional stool containers and GutAlive, a disposable device that minimizes exposure of the gut microbiota to oxygen. Samples from five healthy donors were analysed and 150 differential colonies were recovered and identified by 16S rRNA gene sequencing. Globally, GutAlive maintained extremely oxygen sensitive (EOS) populations that were lost in conventional stool containers, and thus viability of species such as as Akkermansia muciniphila, Faecalibacterium prausnitzii and a novel member of the Clostridiales order was kept. These obligate anaerobes were not recovered using the conventional stool collection device. In conclusion, the use of GutAlive for stool collection and transport optimized the viability and recovery of EOS bacteria in the lab by diminishing oxygen toxicity.

Advances in the field of genome sequencing have enabled a comprehensive analysis and annotation of the dynamics of the protein inventory of cells. This has been proven particularly rewarding for microbial cells, for which the majority of proteins are already accessible to analysis through automatic metagenome annotation. The large-scale in silico screening of proteomes and metaproteomes is key to uncover bioactivities of translational, clinical and biotechnological interest, and to help assign functions to certain proteins, such as those predicted as hypothetical. This work introduces a new method for the prediction of the bioactivity potential of proteomes/metaproteomes, supporting the discovery of functionally relevant proteins based on prior knowledge. This methodology complements functional annotation enrichment methods by allowing the assignment of functions to proteins annotated as hypothetical/putative/uncharacterised, as well as and enabling the detection of specific bioactivities and the recovery of proteins from defined taxa. This work shows how the new method can be applied to screen proteome and metaproteome sets to obtain predictions of clinical or biotechnological interest based on reference datasets. Notably, with this methodology, the large information files obtained after DNA sequencing or protein identification experiments can be associated for translational purposes that, in cases such as antibiotic-resistance pathogens or foodborne diseases, may represent changes in how these important and global health burdens are approached in the clinical practice. Finally, the Sequence-based Expert-driven pRoteome bioactivity Prediction EnvironmENT, a public Web service implemented in Scala functional programming style, is introduced as means to ensure broad access to the method as well as to discuss main implementation issues, such as modularity, extensibility and interoperability.

[Background] Transcriptomics profiling aims to identify and quantify all transcripts present within a cell type or tissue at a particular state, and thus provide information on the genes expressed in specific experimental settings, differentiation or disease conditions. RNA-Seq technology is becoming the standard approach for such studies, but available analysis tools are often hard to install, configure and use by users without advanced bioinformatics skills. [Methods] Within reason, DEWE aims to make RNA-Seq analysis as easy for non-proficient users as for experienced bioinformaticians. DEWE supports two well-established and widely used differential expression analysis workflows: using Bowtie2 or HISAT2 for sequence alignment; and, both applying StringTie for quantification, and Ballgown and edgeR for differential expression analysis. Also, it enables the tailored execution of individual tools as well as helps with the management and visualisation of differential expression results. [Results] DEWE provides a user-friendly interface designed to reduce the learning curve of less knowledgeable users while enabling analysis customisation and software extension by advanced users. Docker technology helps overcome installation and configuration hurdles. In addition, DEWE produces high quality and publication-ready outputs in the form of tab-delimited files and figures, as well as helps researchers with further analyses, such as pathway enrichment analysis. [Conclusions] The abilities of DEWE are exemplified here by practical application to a comparative analysis of monocytes and monocyte-derived dendritic cells, a study of clinical relevance. DEWE installers and documentation are freely available at https://www.sing-group.org/dewe.

This work describes a new procedure that allows the targeted modification of the human gut microbiota by using antibodies raised against bacterial surface-associated proteins specific to the microorganism of interest. To this end, a polyclonal antibody recognising the surface-associated protein Surface Layer Protein A of Lactobacillus acidophilus DSM20079 was developed. By conjugating this antibody with fluorescent probes and magnetic particles, we were able to specifically identify this bacterium both in a synthetic, and in real gut microbiotas by means of a flow cytometry approach. Further, we demonstrated the applicability of this antibody to deplete complex human gut microbiotas from L. acidophilus in a single step. L. acidophilus was found to interact with other bacteria both in synthetic and in real microbiotas, as reflected by its concomitant depletion together with other species. Further optimization of the procedure including a trypsin step enabled to achieve the selective and complete isolation of this species. Depleting a single species from a gut microbiota, using antibodies recognizing specific cell surface elements of the target organism, will open up novel ways to tackle research on the specific immunomodulatory and metabolic contributions of a bacterium of interest in the context of a complex human gut microbiota, including the investigation into therapeutic applications by adding/depleting a key bacterium. This represents the first work in which an antibody/flow-cytometry based application enabled the targeted edition of human gut microbiotas, and represents the basis for the design of precision microbiome-based therapies.

Glycoside hydrolases are responsible for the enzymatic deconstruction of complex carbohydrates. Most of the families are known to conserve the catalytic machinery and molecular mechanisms. This work introduces a new method to predict glycolytic abilities in sequenced genomes and thus, gain a better understanding of how to target specific carbohydrates and identify potentially interesting sources of specialised enzymes. Genome sequences are aligned to those of organisms with expertly curated glycolytic abilities. Clustering of homology scores helps identify organisms that share common abilities and the most promising organisms regarding specific glycolytic abilities. The method has been applied to members of the bacterial families Ruminococcaceae (39 genera), Eubacteriaceae (11 genera) and Lachnospiraceae (59 genera), which hold major representatives of the human gut microbiota. The method predicted the potential presence of glycoside hydrolases in 1701 species of these genera. Here, the validity and practical usefulness of the method is discussed based on the predictions obtained for members of the genus Ruminococcus. Results were consistent with existing literature and offer useful, complementary insights to comparative genomics and physiological testing. The implementation of the Gleukos web portal (http://sing-group.org/gleukos) offers a public service to those interested in targeting microbial carbohydrate metabolism for biotechnological and health applications.

A strictly anaerobic, resistant starch-degrading, bile-tolerant, autolytic strain, IPLA60002, belonging to the family Ruminococcaceae, was isolated from a human bile sample of a liver donor without hepatobiliary disease. Cells were Gram-stain-positive cocci, and 16S rRNA gene and whole genome analyses showed that Ruminococcus bromii was the phylogenetically closest related species to the novel strain IPLA60002, though with average nucleotide identity values below 90%. Biochemically, the new isolate has metabolic features similar to those described previously for gut R. bromii strains, including the ability to degrade a range of different starches. The new isolate, however, produces lactate and shows distinct resistance to the presence of bile salts. Additionally, the novel bile isolate displays an autolytic phenotype after growing in different media. Strain IPLA60002 is phylogenetically distinct from other species within the genus Ruminococcus. Therefore, we propose on the basis of phylogenetic, genomic and metabolic data that the novel IPLA60002 strain isolated from human bile be given the name Ruminococcoides bili gen. nov., sp. nov., within the new proposed genus Ruminococcoides and the family Ruminococcaceae. Strain IPLA60002 (=DSM 110008=LMG 31505) is proposed as the type strain of Ruminococcoides bili.

Dihydrochalcones, phlorizin (PZ) and its aglycone phloretin (PT), have evidenced immunomodulatory effects through several mechanisms. However, the differential metabolic signatures that lead to these properties are largely unknown. Since macrophages play an important role in the immune response, our study aimed to characterise human THP-1 macrophages under PZ and PT exposure. A multiplatform-based untargeted metabolomics approach was used to reveal metabolites associated with the anti-inflammatory mechanisms triggered by the dihydrochalcones in LPS-stimulated macrophages, for the first time. Results showed differential phenotypic response in macrophages for all treatments. Dihydrochalcone treatment in LPS-stimulated macrophages mimics the response under normal conditions, suggesting inhibition of LPS response. Antagonistic effects of dihydrochalcones against LPS was mainly observed in glycerophospholipid and sphingolipid metabolism besides promoting amino acid biosynthesis. Moreover, PT showed greater metabolic activity than PZ. Overall, the findings of this study yielded knowledge about the mechanisms of action PZ and PT at metabolic level in modulating inflammatory response in human cells.

Introducción/Objetivos Faecalibacterium prausnitzii es un miembro de la familia Ruminococcaceae extremadamente sensible al oxígeno. Es una bacteria abundante en el colon de individuos sanos, pero sus niveles disminuyen drásticamente en la enfermedad de Crohn. Además de la producción de butirato (que reduce la inflamación de la mucosa intestinal y es la principal fuente de energía para los colonocitos), se le han atribuido otras propiedades anti-inflamatorias adicionales asociadas a la producción de proteínas secretadas. El objetivo de este estudio fue estudiar el efecto sobre células del sistema inmunitario de microbiotas de donantes sanos y enfermos de Crohn, con diferentes abundancias relativas de F. prausnitzii. Metodología. Se reclutaron 10 microbiotas intestinales de donantes sanos y 10 de enfermos de Crohn. Las microbiotas de donantes sanos se modificaron siguiendo la metodología de anticuerpos y perlas magnéticas descrita por Marcos y colaboradores (Sci Rep 2021, 11:1270), para deplecionarlas o enriquecerlas en F. prausnitzii. Se seleccionaron las microbiotas de donantes sanos con elevada representación de F. prausnitzii y aquellas microbiotas de pacientes con enfermedad de Crohn donde no se detectó F. prausnitzii y se determinó su actividad inmunomoduladora utilizando modelos celulares. Resultados Los resultados aportan nuevos datos sobre el papel que juega F. prausnitzii en la enfermedad de Crohn. La microbiota de enfermos de Crohn suplementada con F. prausnitzii de donantes sanos disminuye la producción de citocinas proinflamatorias, con respecto a la microbiota original. Conclusiones Nuestro estudio contribuye a comprender las funciones de algunas subpoblaciones de la microbiota intestinal que parecen jugar un papel importante en la fisiopatología de la enfermedad de Crohn, mediante la caracterización de sus interacciones con las células del sistema inmunitario.

The invention relates to the field of medical diagnosis, particularly to methods and antibodies useful for the identification of colibactin producing bacteria (pks+ bacteria). Herein are disclosed peptides and antibodies that allow for the detection and isolation of pks+ bacteria, as well as uses and methods of use of said peptides and antibodies

Este libro surge como una iniciativa para compilar una serie de artículos alumbrados a partir de la génesis del Grupo CURIE (Científic@s Unid@s por la Reactivación de la Investigación en España), semilla de la Asociación Española para el Avance de la Ciencia (AEAC). Durante meses sus miembros estuvieron intercambiando reflexiones y debatiendo sobre la distancia entre la ciencia y la sociedad, y la necesidad de crear una asociación que llenase ese vacío entre los científicos y los ciudadanos, que apostase por llevar la ciencia y los conocimientos generados por la misma a toda la sociedad, tal y como establecen la Declaración de Derechos Humanos y la Constitución Española, en su artículo 44.