RESUMEN
Carbohydrate intolerance, commonly linked to the consumption of lactose, fructose, or sorbitol, affects up to 30% of the population in high-income countries. Although sorbitol intolerance is attributed to malabsorption, the underlying mechanism remains unresolved. Here, we show that a history of antibiotic exposure combined with high fat intake triggered long-lasting sorbitol intolerance in mice by reducing Clostridia abundance, which impaired microbial sorbitol catabolism. The restoration of sorbitol catabolism by inoculation with probiotic Escherichia coli protected mice against sorbitol intolerance but did not restore Clostridia abundance. Inoculation with the butyrate producer Anaerostipes caccae restored a normal Clostridia abundance, which protected mice against sorbitol-induced diarrhea even when the probiotic was cleared. Butyrate restored Clostridia abundance by stimulating epithelial peroxisome proliferator-activated receptor-gamma (PPAR-γ) signaling to restore epithelial hypoxia in the colon. Collectively, these mechanistic insights identify microbial sorbitol catabolism as a potential target for approaches for the diagnosis, treatment, and prevention of sorbitol intolerance.
Asunto(s)
Errores Innatos del Metabolismo de los Carbohidratos , Microbioma Gastrointestinal , Sorbitol , Animales , Ratones , Antibacterianos/farmacología , Butiratos , Clostridium , Escherichia coli , Sorbitol/metabolismoRESUMEN
The growth of antimicrobial resistance (AMR) highlights an urgent need to identify bacterial pathogenic functions that may be targets for clinical intervention. Although severe infections profoundly alter host metabolism, prior studies have largely ignored microbial metabolism in this context. Here, we describe an iterative, comparative metabolomics pipeline to uncover microbial metabolic features in the complex setting of a host and apply it to investigate gram-negative bloodstream infection (BSI) in patients. We find elevated levels of bacterially derived acetylated polyamines during BSI and discover the enzyme responsible for their production (SpeG). Blocking SpeG activity reduces bacterial proliferation and slows pathogenesis. Reduction of SpeG activity also enhances bacterial membrane permeability and increases intracellular antibiotic accumulation, allowing us to overcome AMR in culture and in vivo. This study highlights how tools to study pathogen metabolism in the natural context of infection can reveal and prioritize therapeutic strategies for addressing challenging infections.
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Metabolómica , Poliaminas , Humanos , Animales , Poliaminas/metabolismo , Ratones , Bacteriemia/microbiología , Bacteriemia/metabolismo , Bacteriemia/tratamiento farmacológico , Antibacterianos/farmacología , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/metabolismo , FemeninoRESUMEN
Novel antibiotics are urgently needed to combat the antibiotic-resistance crisis. We present a machine-learning-based approach to predict antimicrobial peptides (AMPs) within the global microbiome and leverage a vast dataset of 63,410 metagenomes and 87,920 prokaryotic genomes from environmental and host-associated habitats to create the AMPSphere, a comprehensive catalog comprising 863,498 non-redundant peptides, few of which match existing databases. AMPSphere provides insights into the evolutionary origins of peptides, including by duplication or gene truncation of longer sequences, and we observed that AMP production varies by habitat. To validate our predictions, we synthesized and tested 100 AMPs against clinically relevant drug-resistant pathogens and human gut commensals both in vitro and in vivo. A total of 79 peptides were active, with 63 targeting pathogens. These active AMPs exhibited antibacterial activity by disrupting bacterial membranes. In conclusion, our approach identified nearly one million prokaryotic AMP sequences, an open-access resource for antibiotic discovery.
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Péptidos Antimicrobianos , Aprendizaje Automático , Microbiota , Péptidos Antimicrobianos/farmacología , Péptidos Antimicrobianos/química , Péptidos Antimicrobianos/genética , Humanos , Animales , Antibacterianos/farmacología , Ratones , Metagenoma , Bacterias/efectos de los fármacos , Bacterias/genética , Microbioma Gastrointestinal/efectos de los fármacosRESUMEN
Antimicrobial resistance is a leading mortality factor worldwide. Here, we report the discovery of clovibactin, an antibiotic isolated from uncultured soil bacteria. Clovibactin efficiently kills drug-resistant Gram-positive bacterial pathogens without detectable resistance. Using biochemical assays, solid-state nuclear magnetic resonance, and atomic force microscopy, we dissect its mode of action. Clovibactin blocks cell wall synthesis by targeting pyrophosphate of multiple essential peptidoglycan precursors (C55PP, lipid II, and lipid IIIWTA). Clovibactin uses an unusual hydrophobic interface to tightly wrap around pyrophosphate but bypasses the variable structural elements of precursors, accounting for the lack of resistance. Selective and efficient target binding is achieved by the sequestration of precursors into supramolecular fibrils that only form on bacterial membranes that contain lipid-anchored pyrophosphate groups. This potent antibiotic holds the promise of enabling the design of improved therapeutics that kill bacterial pathogens without resistance development.
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Antibacterianos , Bacterias , Microbiología del Suelo , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Bioensayo , DifosfatosRESUMEN
Two mycobacteriophages were administered intravenously to a male with treatment-refractory Mycobacterium abscessus pulmonary infection and severe cystic fibrosis lung disease. The phages were engineered to enhance their capacity to lyse M. abscessus and were selected specifically as the most effective against the subject's bacterial isolate. In the setting of compassionate use, the evidence of phage-induced lysis was observed using molecular and metabolic assays combined with clinical assessments. M. abscessus isolates pre and post-phage treatment demonstrated genetic stability, with a general decline in diversity and no increased resistance to phage or antibiotics. The anti-phage neutralizing antibody titers to one phage increased with time but did not prevent clinical improvement throughout the course of treatment. The subject received lung transplantation on day 379, and systematic culturing of the explanted lung did not detect M. abscessus. This study describes the course and associated markers of a successful phage treatment of M. abscessus in advanced lung disease.
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Bacteriófagos , Fibrosis Quística , Infecciones por Mycobacterium no Tuberculosas , Mycobacterium abscessus , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacteriófagos/genética , Fibrosis Quística/tratamiento farmacológico , Humanos , Pulmón , Masculino , Infecciones por Mycobacterium no Tuberculosas/terapia , Mycobacterium abscessus/fisiologíaRESUMEN
The intestinal microbiota is an important modulator of graft-versus-host disease (GVHD), which often complicates allogeneic hematopoietic stem cell transplantation (allo-HSCT). Broad-spectrum antibiotics such as carbapenems increase the risk for intestinal GVHD, but mechanisms are not well understood. In this study, we found that treatment with meropenem, a commonly used carbapenem, aggravates colonic GVHD in mice via the expansion of Bacteroides thetaiotaomicron (BT). BT has a broad ability to degrade dietary polysaccharides and host mucin glycans. BT in meropenem-treated allogeneic mice demonstrated upregulated expression of enzymes involved in the degradation of mucin glycans. These mice also had thinning of the colonic mucus layer and decreased levels of xylose in colonic luminal contents. Interestingly, oral xylose supplementation significantly prevented thinning of the colonic mucus layer in meropenem-treated mice. Specific nutritional supplementation strategies, including xylose supplementation, may combat antibiotic-mediated microbiome injury to reduce the risk for intestinal GVHD in allo-HSCT patients.
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Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacteroides , Carbapenémicos/farmacología , Carbapenémicos/uso terapéutico , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Enfermedad Injerto contra Huésped/etiología , Meropenem , Ratones , Mucinas/metabolismo , Moco/metabolismo , Polisacáridos/metabolismo , XilosaRESUMEN
Immune-microbe interactions early in life influence the risk of allergies, asthma, and other inflammatory diseases. Breastfeeding guides healthier immune-microbe relationships by providing nutrients to specialized microbes that in turn benefit the host's immune system. Such bacteria have co-evolved with humans but are now increasingly rare in modern societies. Here we show that a lack of bifidobacteria, and in particular depletion of genes required for human milk oligosaccharide (HMO) utilization from the metagenome, is associated with systemic inflammation and immune dysregulation early in life. In breastfed infants given Bifidobacterium infantis EVC001, which expresses all HMO-utilization genes, intestinal T helper 2 (Th2) and Th17 cytokines were silenced and interferon ß (IFNß) was induced. Fecal water from EVC001-supplemented infants contains abundant indolelactate and B. infantis-derived indole-3-lactic acid (ILA) upregulated immunoregulatory galectin-1 in Th2 and Th17 cells during polarization, providing a functional link between beneficial microbes and immunoregulation during the first months of life.
Asunto(s)
Bifidobacterium/fisiología , Sistema Inmunológico/crecimiento & desarrollo , Sistema Inmunológico/microbiología , Antibacterianos/farmacología , Biomarcadores/metabolismo , Lactancia Materna , Linfocitos T CD4-Positivos/inmunología , Polaridad Celular , Proliferación Celular , Citocinas/metabolismo , Heces/química , Heces/microbiología , Galectina 1/metabolismo , Microbioma Gastrointestinal , Humanos , Indoles/metabolismo , Recién Nacido , Inflamación/sangre , Inflamación/genética , Mucosa Intestinal/inmunología , Metaboloma , Leche Humana/química , Oligosacáridos/metabolismo , Células Th17/inmunología , Células Th2/inmunología , AguaRESUMEN
Emerging evidence indicates a fundamental role for the epigenome in immunity. Here, we mapped the epigenomic and transcriptional landscape of immunity to influenza vaccination in humans at the single-cell level. Vaccination against seasonal influenza induced persistently diminished H3K27ac in monocytes and myeloid dendritic cells (mDCs), which was associated with impaired cytokine responses to Toll-like receptor stimulation. Single-cell ATAC-seq analysis revealed an epigenomically distinct subcluster of monocytes with reduced chromatin accessibility at AP-1-targeted loci after vaccination. Similar effects were observed in response to vaccination with the AS03-adjuvanted H5N1 pandemic influenza vaccine. However, this vaccine also stimulated persistently increased chromatin accessibility at interferon response factor (IRF) loci in monocytes and mDCs. This was associated with elevated expression of antiviral genes and heightened resistance to the unrelated Zika and Dengue viruses. These results demonstrate that vaccination stimulates persistent epigenomic remodeling of the innate immune system and reveal AS03's potential as an epigenetic adjuvant.
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Epigenómica , Inmunidad/genética , Vacunas contra la Influenza/genética , Vacunas contra la Influenza/inmunología , Análisis de la Célula Individual , Transcripción Genética , Vacunación , Adolescente , Adulto , Antibacterianos/farmacología , Antígenos CD34/metabolismo , Antivirales/farmacología , Reprogramación Celular , Cromatina/metabolismo , Citocinas/biosíntesis , Combinación de Medicamentos , Femenino , Regulación de la Expresión Génica , Histonas/metabolismo , Humanos , Inmunidad Innata/genética , Subtipo H5N1 del Virus de la Influenza A/efectos de los fármacos , Subtipo H5N1 del Virus de la Influenza A/inmunología , Interferón Tipo I/metabolismo , Masculino , Células Mieloides/metabolismo , Polisorbatos/farmacología , Escualeno/farmacología , Receptores Toll-Like/metabolismo , Factor de Transcripción AP-1/metabolismo , Transcriptoma/genética , Adulto Joven , alfa-Tocoferol/farmacologíaRESUMEN
Ticks transmit a diverse array of microbes to vertebrate hosts, including human pathogens, which has led to a human-centric focus in this vector system. Far less is known about pathogens of ticks themselves. Here, we discover that a toxin in blacklegged ticks (Ixodes scapularis) horizontally acquired from bacteria-called domesticated amidase effector 2 (dae2)-has evolved to kill mammalian skin microbes with remarkable efficiency. Secreted into the saliva and gut of ticks, Dae2 limits skin-associated staphylococci in ticks while feeding. In contrast, Dae2 has no intrinsic ability to kill Borrelia burgdorferi, the tick-borne Lyme disease bacterial pathogen. These findings suggest ticks resist their own pathogens while tolerating symbionts. Thus, just as tick symbionts can be pathogenic to humans, mammalian commensals can be harmful to ticks. Our study underscores how virulence is context-dependent and bolsters the idea that "pathogen" is a status and not an identity.
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Bacterias/metabolismo , Factores Inmunológicos/metabolismo , Ixodes/fisiología , Piel/microbiología , Simbiosis , Animales , Antibacterianos/farmacología , Biocatálisis , Pared Celular/metabolismo , Conducta Alimentaria , Femenino , Tracto Gastrointestinal/metabolismo , Interacciones Huésped-Patógeno , Ratones , Modelos Moleculares , Peptidoglicano/metabolismo , Filogenia , Saliva/metabolismo , Glándulas Salivales/metabolismo , Staphylococcus epidermidis/fisiología , Homología Estructural de Proteína , Especificidad por Sustrato , Regulación hacia ArribaRESUMEN
Due to the rapid emergence of antibiotic-resistant bacteria, there is a growing need to discover new antibiotics. To address this challenge, we trained a deep neural network capable of predicting molecules with antibacterial activity. We performed predictions on multiple chemical libraries and discovered a molecule from the Drug Repurposing Hub-halicin-that is structurally divergent from conventional antibiotics and displays bactericidal activity against a wide phylogenetic spectrum of pathogens including Mycobacterium tuberculosis and carbapenem-resistant Enterobacteriaceae. Halicin also effectively treated Clostridioides difficile and pan-resistant Acinetobacter baumannii infections in murine models. Additionally, from a discrete set of 23 empirically tested predictions from >107 million molecules curated from the ZINC15 database, our model identified eight antibacterial compounds that are structurally distant from known antibiotics. This work highlights the utility of deep learning approaches to expand our antibiotic arsenal through the discovery of structurally distinct antibacterial molecules.
Asunto(s)
Antibacterianos/farmacología , Descubrimiento de Drogas/métodos , Aprendizaje Automático , Tiadiazoles/farmacología , Acinetobacter baumannii/efectos de los fármacos , Animales , Antibacterianos/química , Quimioinformática/métodos , Clostridioides difficile/efectos de los fármacos , Bases de Datos de Compuestos Químicos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Mycobacterium tuberculosis/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Tiadiazoles/químicaRESUMEN
The rise of antibiotic resistance and declining discovery of new antibiotics has created a global health crisis. Of particular concern, no new antibiotic classes have been approved for treating Gram-negative pathogens in decades. Here, we characterize a compound, SCH-79797, that kills both Gram-negative and Gram-positive bacteria through a unique dual-targeting mechanism of action (MoA) with undetectably low resistance frequencies. To characterize its MoA, we combined quantitative imaging, proteomic, genetic, metabolomic, and cell-based assays. This pipeline demonstrates that SCH-79797 has two independent cellular targets, folate metabolism and bacterial membrane integrity, and outperforms combination treatments in killing methicillin-resistant Staphylococcus aureus (MRSA) persisters. Building on the molecular core of SCH-79797, we developed a derivative, Irresistin-16, with increased potency and showed its efficacy against Neisseria gonorrhoeae in a mouse vaginal infection model. This promising antibiotic lead suggests that combining multiple MoAs onto a single chemical scaffold may be an underappreciated approach to targeting challenging bacterial pathogens.
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Bacterias Gramnegativas/efectos de los fármacos , Pirroles/metabolismo , Pirroles/farmacología , Quinazolinas/metabolismo , Quinazolinas/farmacología , Animales , Antibacterianos/farmacología , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Farmacorresistencia Bacteriana/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Femenino , Ácido Fólico/metabolismo , Bacterias Grampositivas/efectos de los fármacos , Células HEK293 , Humanos , Masculino , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Ovariectomía , Proteómica , Pseudomonas aeruginosa/efectos de los fármacosRESUMEN
Chikungunya virus (CHIKV), an emerging alphavirus, has infected millions of people. However, the factors modulating disease outcome remain poorly understood. Here, we show in germ-free mice or in oral antibiotic-treated conventionally housed mice with depleted intestinal microbiomes that greater CHIKV infection and spread occurs within 1 day of virus inoculation. Alteration of the microbiome alters TLR7-MyD88 signaling in plasmacytoid dendritic cells (pDCs) and blunts systemic production of type I interferon (IFN). Consequently, circulating monocytes express fewer IFN-stimulated genes and become permissive for CHIKV infection. Reconstitution with a single bacterial species, Clostridium scindens, or its derived metabolite, the secondary bile acid deoxycholic acid, can restore pDC- and MyD88-dependent type I IFN responses to restrict systemic CHIKV infection and transmission back to vector mosquitoes. Thus, symbiotic intestinal bacteria modulate antiviral immunity and levels of circulating alphaviruses within hours of infection through a bile acid-pDC-IFN signaling axis, which affects viremia, dissemination, and potentially transmission.
Asunto(s)
Ácidos y Sales Biliares/metabolismo , Fiebre Chikungunya/patología , Microbioma Gastrointestinal , Interferón Tipo I/metabolismo , Animales , Antibacterianos/farmacología , Fiebre Chikungunya/inmunología , Fiebre Chikungunya/veterinaria , Virus Chikungunya/genética , Virus Chikungunya/aislamiento & purificación , Clostridiales/fisiología , Células Dendríticas/citología , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Trasplante de Microbiota Fecal , Microbioma Gastrointestinal/efectos de los fármacos , Masculino , Glicoproteínas de Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Monocitos/citología , Monocitos/inmunología , Monocitos/metabolismo , Factor 88 de Diferenciación Mieloide/deficiencia , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/metabolismo , ARN Viral/sangre , Factor de Transcripción STAT1/deficiencia , Transducción de Señal , Receptor Toll-Like 7/metabolismoRESUMEN
Throughout a 24-h period, the small intestine (SI) is exposed to diurnally varying food- and microbiome-derived antigenic burdens but maintains a strict immune homeostasis, which when perturbed in genetically susceptible individuals, may lead to Crohn disease. Herein, we demonstrate that dietary content and rhythmicity regulate the diurnally shifting SI epithelial cell (SIEC) transcriptional landscape through modulation of the SI microbiome. We exemplify this concept with SIEC major histocompatibility complex (MHC) class II, which is diurnally modulated by distinct mucosal-adherent SI commensals, while supporting downstream diurnal activity of intra-epithelial IL-10+ lymphocytes regulating the SI barrier function. Disruption of this diurnally regulated diet-microbiome-MHC class II-IL-10-epithelial barrier axis by circadian clock disarrangement, alterations in feeding time or content, or epithelial-specific MHC class II depletion leads to an extensive microbial product influx, driving Crohn-like enteritis. Collectively, we highlight nutritional features that modulate SI microbiome, immunity, and barrier function and identify dietary, epithelial, and immune checkpoints along this axis to be potentially exploitable in future Crohn disease interventions.
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Enfermedad de Crohn/microbiología , Células Epiteliales/metabolismo , Microbioma Gastrointestinal , Antígenos de Histocompatibilidad Clase II/metabolismo , Intestino Delgado/inmunología , Intestino Delgado/microbiología , Transcriptoma/genética , Animales , Antibacterianos/farmacología , Relojes Circadianos/fisiología , Enfermedad de Crohn/inmunología , Enfermedad de Crohn/metabolismo , Dieta , Células Epiteliales/citología , Células Epiteliales/inmunología , Citometría de Flujo , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/genética , Perfilación de la Expresión Génica , Antígenos de Histocompatibilidad Clase II/genética , Homeostasis , Hibridación Fluorescente in Situ , Interleucina-10/metabolismo , Interleucina-10/farmacología , Intestino Delgado/fisiología , Linfocitos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Periodicidad , Linfocitos T/inmunología , Transcriptoma/fisiologíaRESUMEN
Current machine learning techniques enable robust association of biological signals with measured phenotypes, but these approaches are incapable of identifying causal relationships. Here, we develop an integrated "white-box" biochemical screening, network modeling, and machine learning approach for revealing causal mechanisms and apply this approach to understanding antibiotic efficacy. We counter-screen diverse metabolites against bactericidal antibiotics in Escherichia coli and simulate their corresponding metabolic states using a genome-scale metabolic network model. Regression of the measured screening data on model simulations reveals that purine biosynthesis participates in antibiotic lethality, which we validate experimentally. We show that antibiotic-induced adenine limitation increases ATP demand, which elevates central carbon metabolism activity and oxygen consumption, enhancing the killing effects of antibiotics. This work demonstrates how prospective network modeling can couple with machine learning to identify complex causal mechanisms underlying drug efficacy.
Asunto(s)
Antibacterianos/metabolismo , Antibacterianos/farmacología , Redes y Vías Metabólicas/efectos de los fármacos , Adenina/metabolismo , Biología Computacional/métodos , Evaluación Preclínica de Medicamentos/métodos , Escherichia coli/metabolismo , Aprendizaje Automático , Redes y Vías Metabólicas/inmunología , Modelos Teóricos , Purinas/metabolismoRESUMEN
Emerging evidence indicates a central role for the microbiome in immunity. However, causal evidence in humans is sparse. Here, we administered broad-spectrum antibiotics to healthy adults prior and subsequent to seasonal influenza vaccination. Despite a 10,000-fold reduction in gut bacterial load and long-lasting diminution in bacterial diversity, antibody responses were not significantly affected. However, in a second trial of subjects with low pre-existing antibody titers, there was significant impairment in H1N1-specific neutralization and binding IgG1 and IgA responses. In addition, in both studies antibiotics treatment resulted in (1) enhanced inflammatory signatures (including AP-1/NR4A expression), observed previously in the elderly, and increased dendritic cell activation; (2) divergent metabolic trajectories, with a 1,000-fold reduction in serum secondary bile acids, which was highly correlated with AP-1/NR4A signaling and inflammasome activation. Multi-omics integration revealed significant associations between bacterial species and metabolic phenotypes, highlighting a key role for the microbiome in modulating human immunity.
Asunto(s)
Antibacterianos/farmacología , Anticuerpos Antivirales/inmunología , Microbioma Gastrointestinal/fisiología , Inmunidad/efectos de los fármacos , Vacunas contra la Influenza/inmunología , Gripe Humana/inmunología , Adolescente , Adulto , Formación de Anticuerpos , Femenino , Microbioma Gastrointestinal/efectos de los fármacos , Voluntarios Sanos , Humanos , Inmunogenicidad Vacunal/inmunología , Subtipo H1N1 del Virus de la Influenza A/inmunología , Masculino , Adulto JovenRESUMEN
Translation elongation is a highly coordinated, multistep, multifactor process that ensures accurate and efficient addition of amino acids to a growing nascent-peptide chain encoded in the sequence of translated messenger RNA (mRNA). Although translation elongation is heavily regulated by external factors, there is clear evidence that mRNA and nascent-peptide sequences control elongation dynamics, determining both the sequence and structure of synthesized proteins. Advances in methods have driven experiments that revealed the basic mechanisms of elongation as well as the mechanisms of regulation by mRNA and nascent-peptide sequences. In this review, we highlight how mRNA and nascent-peptide elements manipulate the translation machinery to alter the dynamics and pathway of elongation.
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Extensión de la Cadena Peptídica de Translación , ARN Mensajero/genética , ARN Mensajero/metabolismo , Secuencia de Aminoácidos , Animales , Antibacterianos/farmacología , Codón/genética , Epigénesis Genética , Sistema de Lectura Ribosómico/genética , Humanos , Cinética , Modelos Biológicos , Extensión de la Cadena Peptídica de Translación/efectos de los fármacos , ARN Mensajero/química , Ribosomas/metabolismoRESUMEN
Genetic information is translated into proteins by the ribosome. Structural studies of the ribosome and of its complexes with factors and inhibitors have provided invaluable information on the mechanism of protein synthesis. Ribosome inhibitors are among the most successful antimicrobial drugs and constitute more than half of all medicines used to treat infections. However, bacterial infections are becoming increasingly difficult to treat because the microbes have developed resistance to the most effective antibiotics, creating a major public health care threat. This has spurred a renewed interest in structure-function studies of protein synthesis inhibitors, and in few cases, compounds have been developed into potent therapeutic agents against drug-resistant pathogens. In this review, we describe the modes of action of many ribosome-targeting antibiotics, highlight the major resistance mechanisms developed by pathogenic bacteria, and discuss recent advances in structure-assisted design of new molecules.
Asunto(s)
Antibacterianos/farmacología , Ribosomas/efectos de los fármacos , Animales , Antibacterianos/química , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/farmacología , Sitios de Unión , Diseño de Fármacos , Farmacorresistencia Microbiana , Humanos , Modelos Biológicos , Modelos Moleculares , Biosíntesis de Proteínas/efectos de los fármacos , Inhibidores de la Síntesis de la Proteína/química , Inhibidores de la Síntesis de la Proteína/farmacología , Ribosomas/química , Ribosomas/metabolismo , Relación Estructura-ActividadRESUMEN
The immune system is imprinted by gut microbes in early life. In this issue of Immunity, Perdijk et al. show that dysregulation of airway epithelial function by neonatal antibiotic treatment can be reversed by supplementation with a depleted microbial metabolite.
Asunto(s)
Antibacterianos , Microbioma Gastrointestinal , Humanos , Antibacterianos/farmacología , Microbioma Gastrointestinal/inmunología , Recién NacidoRESUMEN
Antibiotic use in early life disrupts microbial colonization and increases the risk of developing allergies and asthma. We report that mice given antibiotics in early life (EL-Abx), but not in adulthood, were more susceptible to house dust mite (HDM)-induced allergic airway inflammation. This susceptibility was maintained even after normalization of the gut microbiome. EL-Abx decreased systemic levels of indole-3-propionic acid (IPA), which induced long-term changes to cellular stress, metabolism, and mitochondrial respiration in the lung epithelium. IPA reduced mitochondrial respiration and superoxide production and altered chemokine and cytokine production. Consequently, early-life IPA supplementation protected EL-Abx mice against exacerbated HDM-induced allergic airway inflammation in adulthood. These results reveal a mechanism through which EL-Abx can predispose the lung to allergic airway inflammation and highlight a possible preventative approach to mitigate the detrimental consequences of EL-Abx.
Asunto(s)
Antibacterianos , Asma , Disbiosis , Microbioma Gastrointestinal , Indoles , Pyroglyphidae , Animales , Ratones , Disbiosis/inmunología , Indoles/farmacología , Antibacterianos/efectos adversos , Antibacterianos/farmacología , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/inmunología , Asma/inmunología , Pyroglyphidae/inmunología , Pulmón/inmunología , Pulmón/patología , Ratones Endogámicos C57BL , Femenino , Inflamación/inmunología , Modelos Animales de Enfermedad , Mitocondrias/metabolismo , Citocinas/metabolismo , Hipersensibilidad/inmunología , PropionatosRESUMEN
Peptides have great potential to combat antibiotic resistance. While many platforms can screen peptides for their ability to bind to target cells, there are virtually no platforms that directly assess the functionality of peptides. This limitation is exacerbated when identifying antimicrobial peptides because the phenotype, death, selects against itself and has caused a scientific bottleneck that confines research to a few naturally occurring classes of antimicrobial peptides. We have used this seeming dissonance to develop Surface Localized Antimicrobial Display (SLAY), a platform that allows screening of unlimited numbers of peptides of any length, composition, and structure in a single tube for antimicrobial activity. Using SLAY, we screened â¼800,000 random peptide sequences for antimicrobial function and identified thousands of active sequences, dramatically increasing the number of known antimicrobial sequences. SLAY hits present with different potential mechanisms of peptide action and access to areas of antimicrobial physicochemical space beyond what nature has evolved. VIDEO ABSTRACT.