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1.
Nat Prod Rep ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39129507

RESUMEN

Covering 1986 to presentNatural product drug discovery at Novartis has a long and successful history of delivering life saving medicines to millions of patients. In this viewpoint, we are presenting the tools we use and challenges we face as we advance natural products from early research into development and beyond. We are leveraging our collection of 90 000 microbial strains and 20 000 isolated natural products to find new medications in an interdisciplinary approach that requires expertise in microbiology, computational biology, synthetic biology, chemistry, and process development. Technological advances, particularly in genome engineering and data science have transformed our field, accelerating discovery and facilitating sustainable compound supply. Emerging new modalities such as antibody drug conjugates, radioligand therapies and xRNA-based medications offer new opportunities for natural product-derived drugs. By taking advantage of these new modalities and the most recent research technologies, natural products will significantly contribute to the medicines of the future.

2.
Chemistry ; 30(3): e202302350, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-37855054

RESUMEN

For a potential application of FK506 in the treatment of acute kidney failure only the FKBP12 binding capability of the compound is required, while the immunosuppressive activity via calcineurin binding is considered as a likely risk to the patients. The methoxy groups at C13 and C15 are thought to have significant influence on the immunosuppressive activity of the molecule. Consequently, FK506 analogs with different functionalities at C13 and C15 were generated by targeted CRISPR editing of the AT domains in module 7 and 8 of the biosynthetic assembly line in Streptomyces tsukubaensis. In addition, the corresponding FK520 (C21 ethyl derivative of FK506) analogs could be obtained by media adjustments. The compounds were tested for their bioactivity in regards to FKBP12 binding, BMP potentiation and calcineurin sparing. 15-desmethoxy FK506 was superior to the other tested analogs as it did not inhibit calcineurin but retained high potency towards FKBP12 binding and BMP potentiation.


Asunto(s)
Calcineurina , Streptomyces , Tacrolimus , Humanos , Tacrolimus/farmacología , Tacrolimus/metabolismo , Calcineurina/metabolismo , Proteína 1A de Unión a Tacrolimus/genética , Proteína 1A de Unión a Tacrolimus/metabolismo , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Inmunosupresores/farmacología , Inmunosupresores/química
3.
Antimicrob Agents Chemother ; 65(9): e0097821, 2021 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-34228543

RESUMEN

Rifampicin is an effective drug for treating tuberculosis (TB) but is not used to treat Mycobacterium abscessus infections due to poor in vitro activity. While rifabutin, another rifamycin, has better anti-M. abscessus activity, its activity is far from the nanomolar potencies of rifamycins against Mycobacterium tuberculosis. Here, we asked (i) why is rifabutin more active against M. abscessus than rifampicin, and (ii) why is rifabutin's anti-M. abscessus activity poorer than its anti-TB activity? Comparative analysis of naphthoquinone- versus naphthohydroquinone-containing rifamycins suggested that the improved activity of rifabutin over rifampicin is linked to its less readily oxidizable naphthoquinone core. Although rifabutin is resistant to bacterial oxidation, metabolite and genetic analyses showed that this rifamycin is metabolized by the ADP-ribosyltransferase ArrMab like rifampicin, preventing it from achieving the nanomolar activity that it displays against M. tuberculosis. Based on the identified dual mechanism of intrinsic rifamycin resistance, we hypothesized that rifamycins more potent than rifabutin should contain the molecule's naphthoquinone core plus a modification that blocks ADP-ribosylation at its C-23. To test these predictions, we performed a blinded screen of a diverse collection of 189 rifamycins and identified two molecules more potent than rifabutin. As predicted, these compounds contained both a more oxidatively resistant naphthoquinone core and C-25 modifications that blocked ADP-ribosylation. Together, this work revealed dual bacterial metabolism as the mechanism of intrinsic resistance of M. abscessus to rifamycins and provides proof of concept for the repositioning of rifamycins for M. abscessus disease by developing derivatives that resist both bacterial oxidation and ADP-ribosylation.


Asunto(s)
Mycobacterium abscessus , Rifamicinas , ADP-Ribosilación , Pruebas de Sensibilidad Microbiana , Rifabutina/farmacología , Rifamicinas/farmacología
4.
Chimia (Aarau) ; 75(7): 620-633, 2021 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-34523403

RESUMEN

Natural Products (NPs) are molecular' special equipment ' that impart survival benefits on their producers in nature. Due to their evolved functions to modulate biology these privileged metabolites are substantially represented in the drug market and are continuing to contribute to the discovery of innovative medicines such as the recently approved semi-synthetic derivative of the bacterial alkaloid staurosporin in oncology indications. The innovation of low molecular weight compounds in modern drug discovery is built on rapid progress in chemical, molecular biological, pharmacological and data sciences, which together provide a rich understanding of disease-driving molecular interactions and how to modulate them. NPs investigated in these pharmaceutical research areas create new perspectives on their chemical and biological features and thereby new chances to advance medical research. New methods in analytical chemistry linked with searchable NP-databases solved the issue of reisolation and enabled targeted and efficient access to novel molecules from nature. Cheminformatics delivers high resolution descriptions of NPs and explores the substructures that systematically map NP-chemical space by sp³-enriched fragments. Whole genome sequencing has revealed the existence of collocated gene clusters that form larger functional entities together with proximate resistance factors thus avoiding self-inhibition of the encoded metabolites. The analysis of bacterial and fungal genes provides tantalizing glimpses of new compound-target pairs of therapeutic value. Furthermore, a dedicated investigation of structurally unique, selectively active NPs in chemical biology demonstrates their extraordinary power as shuttles between new biological target spaces of pharmaceutical relevance.


Asunto(s)
Productos Biológicos , Bases de Datos Factuales , Descubrimiento de Drogas , Industria Farmacéutica
5.
J Biol Chem ; 293(52): 19982-19995, 2018 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-30327433

RESUMEN

Actinobacteria possess a great wealth of pathways for production of bioactive compounds. Following advances in genome mining, dozens of natural product (NP) gene clusters are routinely found in each actinobacterial genome; however, the modus operandi of this large arsenal is poorly understood. During investigations of the secondary metabolome of Streptomyces rapamycinicus, the producer of rapamycin, we observed accumulation of two compounds never before reported from this organism. Structural elucidation revealed actinoplanic acid A and its demethyl analogue. Actinoplanic acids (APLs) are potent inhibitors of Ras farnesyltransferase and therefore represent bioactive compounds of medicinal interest. Supported with the unique structure of these polyketides and using genome mining, we identified a gene cluster responsible for their biosynthesis in S. rapamycinicus Based on experimental evidence and genetic organization of the cluster, we propose a stepwise biosynthesis of APL, the first bacterial example of a pathway incorporating the rare tricarballylic moiety into an NP. Although phylogenetically distant, the pathway shares some of the biosynthetic principles with the mycotoxins fumonisins. Namely, the core polyketide is acylated with the tricarballylate by an atypical nonribosomal peptide synthetase-catalyzed ester formation. Finally, motivated by the conserved colocalization of the rapamycin and APL pathway clusters in S. rapamycinicus and all other rapamycin-producing actinobacteria, we confirmed a strong synergism of these compounds in antifungal assays. Mining for such evolutionarily conserved coharboring of pathways would likely reveal further examples of NP sets, attacking multiple targets on the same foe. These could then serve as a guide for development of new combination therapies.


Asunto(s)
Vías Biosintéticas , Lactonas/metabolismo , Familia de Multigenes , Policétidos/metabolismo , Sirolimus/metabolismo , Streptomyces/metabolismo , Metilación , Metabolismo Secundario , Streptomyces/genética
6.
Nat Chem Biol ; 13(12): 1239-1244, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28991239

RESUMEN

Tim17 and Tim23 are the main subunits of the TIM23 complex, one of the two major essential mitochondrial inner-membrane protein translocon machineries (TIMs). No chemical probes that specifically inhibit TIM23-dependent protein import were known to exist. Here we show that the natural product stendomycin, produced by Streptomyces hygroscopicus, is a potent and specific inhibitor of the TIM23 complex in yeast and mammalian cells. Furthermore, stendomycin-mediated blockage of the TIM23 complex does not alter normal processing of the major regulatory mitophagy kinase PINK1, but TIM23 is required to stabilize PINK1 on the outside of mitochondria to initiate mitophagy upon membrane depolarization.


Asunto(s)
Proteínas Mitocondriales/metabolismo , Péptidos/farmacología , Proteínas de Saccharomyces cerevisiae/antagonistas & inhibidores , Péptidos Catiónicos Antimicrobianos , Relación Dosis-Respuesta a Droga , Células HeLa , Humanos , Proteínas de Transporte de Membrana/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Proteínas del Complejo de Importación de Proteínas Precursoras Mitocondriales , Estructura Molecular , Péptidos/química , Transporte de Proteínas/efectos de los fármacos , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Relación Estructura-Actividad , Células Tumorales Cultivadas
7.
J Cell Sci ; 128(6): 1217-29, 2015 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-25616894

RESUMEN

A new cyclic decadepsipeptide was isolated from Chaetosphaeria tulasneorum with potent bioactivity on mammalian and yeast cells. Chemogenomic profiling in S. cerevisiae indicated that the Sec61 translocon complex, the machinery for protein translocation and membrane insertion at the endoplasmic reticulum, is the target. The profiles were similar to those of cyclic heptadepsipeptides of a distinct chemotype (including HUN-7293 and cotransin) that had previously been shown to inhibit cotranslational translocation at the mammalian Sec61 translocon. Unbiased, genome-wide mutagenesis followed by full-genome sequencing in both fungal and mammalian cells identified dominant mutations in Sec61p (yeast) or Sec61α1 (mammals) that conferred resistance. Most, but not all, of these mutations affected inhibition by both chemotypes, despite an absence of structural similarity. Biochemical analysis confirmed inhibition of protein translocation into the endoplasmic reticulum of both co- and post-translationally translocated substrates by both chemotypes, demonstrating a mechanism independent of a translating ribosome. Most interestingly, both chemotypes were found to also inhibit SecYEG, the bacterial Sec61 translocon homolog. We suggest 'decatransin' as the name for this new decadepsipeptide translocation inhibitor.


Asunto(s)
Productos Biológicos/farmacología , Retículo Endoplásmico/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Transporte de Proteínas/efectos de los fármacos , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Animales , Ascomicetos/metabolismo , Células COS , Células Cultivadas , Chlorocebus aethiops , Células HCT116 , Humanos , Proteínas de la Membrana/antagonistas & inhibidores , Péptidos Cíclicos/farmacología , Polimorfismo de Nucleótido Simple/genética , Canales de Translocación SEC , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crecimiento & desarrollo
8.
Nat Chem Biol ; 11(12): 958-66, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26479441

RESUMEN

High-throughput screening (HTS) is an integral part of early drug discovery. Herein, we focused on those small molecules in a screening collection that have never shown biological activity despite having been exhaustively tested in HTS assays. These compounds are referred to as 'dark chemical matter' (DCM). We quantified DCM, validated it in quality control experiments, described its physicochemical properties and mapped it into chemical space. Through analysis of prospective reporter-gene assay, gene expression and yeast chemogenomics experiments, we evaluated the potential of DCM to show biological activity in future screens. We demonstrated that, despite the apparent lack of activity, occasionally these compounds can result in potent hits with unique activity and clean safety profiles, which makes them valuable starting points for lead optimization efforts. Among the identified DCM hits was a new antifungal chemotype with strong activity against the pathogen Cryptococcus neoformans but little activity at targets relevant to human safety.


Asunto(s)
Antifúngicos/farmacología , Cryptococcus neoformans/efectos de los fármacos , Descubrimiento de Drogas , Ensayos Analíticos de Alto Rendimiento , Antifúngicos/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Relación Estructura-Actividad
9.
Angew Chem Int Ed Engl ; 54(35): 10149-54, 2015 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-26179970

RESUMEN

Cultivation of myxobacteria of the Nannocystis genus led to the isolation and structure elucidation of a class of novel cyclic lactone inhibitors of elongation factor 1. Whole genome sequence analysis and annotation enabled identification of the putative biosynthetic cluster and synthesis process. In biological assays the compounds displayed anti-fungal and cytotoxic activity. Combined genetic and proteomic approaches identified the eukaryotic translation elongation factor 1α (EF-1α) as the primary target for this compound class. Nannocystin A (1) displayed differential activity across various cancer cell lines and EEF1A1 expression levels appear to be the main differentiating factor. Biochemical and genetic evidence support an overlapping binding site of 1 with the anti-cancer compound didemnin B on EF-1α. This myxobacterial chemotype thus offers an interesting starting point for further investigations of the potential of therapeutics targeting elongation factor 1.


Asunto(s)
Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Compuestos Macrocíclicos/farmacología , Myxococcales/fisiología , Neoplasias/patología , Factor 1 de Elongación Peptídica/antagonistas & inhibidores , Antifúngicos/química , Antifúngicos/farmacología , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Candida albicans/efectos de los fármacos , Genómica/métodos , Humanos , Compuestos Macrocíclicos/química , Estructura Molecular , Neoplasias/tratamiento farmacológico , Factor 1 de Elongación Peptídica/genética , Factor 1 de Elongación Peptídica/metabolismo , Proteómica/métodos , Relación Estructura-Actividad , Células Tumorales Cultivadas
10.
Cell Chem Biol ; 28(10): 1407-1419.e6, 2021 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-33794192

RESUMEN

Three limonoid natural products with selective anti-proliferative activity against BRAF(V600E) and NRAS(Q61K)-mutation-dependent melanoma cell lines were identified. Differential transcriptome analysis revealed dependency of compound activity on expression of the mitochondrial cytochrome P450 oxidase CYP27A1, a transcriptional target of melanogenesis-associated transcription factor (MITF). We determined that CYP27A1 activity is necessary for the generation of a reactive metabolite that proceeds to inhibit cellular proliferation. A genome-wide small interfering RNA screen in combination with chemical proteomics experiments revealed gene-drug functional epistasis, suggesting that these compounds target mitochondrial biogenesis and inhibit tumor bioenergetics through a covalent mechanism. Our work suggests a strategy for melanoma-specific targeting by exploiting the expression of MITF target gene CYP27A1 and inhibiting mitochondrial oxidative phosphorylation in BRAF mutant melanomas.


Asunto(s)
Colestanotriol 26-Monooxigenasa/metabolismo , Limoninas/farmacología , Mitocondrias/efectos de los fármacos , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Productos Biológicos/química , Productos Biológicos/metabolismo , Productos Biológicos/farmacología , Productos Biológicos/uso terapéutico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Colestanotriol 26-Monooxigenasa/antagonistas & inhibidores , Colestanotriol 26-Monooxigenasa/genética , Humanos , Limoninas/química , Limoninas/metabolismo , Limoninas/uso terapéutico , Melanoma/tratamiento farmacológico , Melanoma/patología , Factor de Transcripción Asociado a Microftalmía/genética , Factor de Transcripción Asociado a Microftalmía/metabolismo , Mitocondrias/metabolismo , Fosforilación Oxidativa/efectos de los fármacos , Regiones Promotoras Genéticas , Unión Proteica , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismo
11.
Cell Chem Biol ; 28(9): 1271-1282.e12, 2021 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-33894161

RESUMEN

Acute kidney injury (AKI) is a life-threatening disease with no known curative or preventive therapies. Data from multiple animal models and human studies have linked dysregulation of bone morphogenetic protein (BMP) signaling to AKI. Small molecules that potentiate endogenous BMP signaling should have a beneficial effect in AKI. We performed a high-throughput phenotypic screen and identified a series of FK506 analogs that act as potent BMP potentiators by sequestering FKBP12 from BMP type I receptors. We further showed that calcineurin inhibition was not required for this activity. We identified a calcineurin-sparing FK506 analog oxtFK through late-stage functionalization and structure-guided design. OxtFK demonstrated an improved safety profile in vivo relative to FK506. OxtFK stimulated BMP signaling in vitro and in vivo and protected the kidneys in an AKI mouse model, making it a promising candidate for future development as a first-in-class therapeutic for diseases with dysregulated BMP signaling.


Asunto(s)
Lesión Renal Aguda/tratamiento farmacológico , Proteínas Morfogenéticas Óseas/metabolismo , Tacrolimus/farmacología , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Ensayos Analíticos de Alto Rendimiento , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Fenotipo , Tacrolimus/análogos & derivados , Tacrolimus/química
12.
J Med Chem ; 63(23): 14425-14447, 2020 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-33140646

RESUMEN

This article summarizes the evolution of the screening deck at the Novartis Institutes for BioMedical Research (NIBR). Historically, the screening deck was an assembly of all available compounds. In 2015, we designed a first deck to facilitate access to diverse subsets with optimized properties. We allocated the compounds as plated subsets on a 2D grid with property based ranking in one dimension and increasing structural redundancy in the other. The learnings from the 2015 screening deck were applied to the design of a next generation in 2019. We found that using traditional leadlikeness criteria (mainly MW, clogP) reduces the hit rates of attractive chemical starting points in subset screening. Consequently, the 2019 deck relies on solubility and permeability to select preferred compounds. The 2019 design also uses NIBR's experimental assay data and inferred biological activity profiles in addition to structural diversity to define redundancy across the compound sets.


Asunto(s)
Bibliotecas de Moléculas Pequeñas/química , Diseño de Fármacos , Evaluación Preclínica de Medicamentos/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Bibliotecas de Moléculas Pequeñas/farmacología
13.
J Clin Invest ; 130(7): 3848-3864, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32315290

RESUMEN

Cancer cells can develop a strong addiction to discrete molecular regulators, which control the aberrant gene expression programs that drive and maintain the cancer phenotype. Here, we report the identification of the RNA-binding protein HuR/ELAVL1 as a central oncogenic driver for malignant peripheral nerve sheath tumors (MPNSTs), which are highly aggressive sarcomas that originate from cells of the Schwann cell lineage. HuR was found to be highly elevated and bound to a multitude of cancer-associated transcripts in human MPNST samples. Accordingly, genetic and pharmacological inhibition of HuR had potent cytostatic and cytotoxic effects on tumor growth, and strongly suppressed metastatic capacity in vivo. Importantly, we linked the profound tumorigenic function of HuR to its ability to simultaneously regulate multiple essential oncogenic pathways in MPNST cells, including the Wnt/ß-catenin, YAP/TAZ, RB/E2F, and BET pathways, which converge on key transcriptional networks. Given the exceptional dependency of MPNST cells on HuR for survival, proliferation, and dissemination, we propose that HuR represents a promising therapeutic target for MPNST treatment.


Asunto(s)
Carcinogénesis/metabolismo , Proliferación Celular , Proteína 1 Similar a ELAV/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias de la Vaina del Nervio/metabolismo , Transducción de Señal , Animales , Carcinogénesis/genética , Carcinogénesis/patología , Línea Celular Tumoral , Proteína 1 Similar a ELAV/genética , Humanos , Ratones , Metástasis de la Neoplasia , Proteínas de Neoplasias/genética , Neoplasias de la Vaina del Nervio/genética , Neoplasias de la Vaina del Nervio/patología
14.
J Am Chem Soc ; 131(16): 5946-55, 2009 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-19338336

RESUMEN

We identified the thiomuracins, a novel family of thiopeptides produced by a rare-actinomycete bacterium typed as a Nonomuraea species, via a screen for inhibition of growth of the bacterial pathogen Staphylococcus aureus. Thiopeptides are a class of macrocyclic, highly modified peptides that are decorated by thiazoles and defined by a central six-membered heterocyclic ring system. Mining the genomes of thiopeptide-producing strains revealed the elusive biosynthetic route for this class of antibiotics. The thiopeptides are chromosomally encoded, ribosomally synthesized proteins, and isolation of gene clusters for production of thiomuracin and the related thiopeptide GE2270A revealed the post-translational machinery required for maturation. The target of the thiomuracins was identified as bacterial Elongation Factor Tu (EF-Tu). In addition to potently inhibiting a target that is unexploited by marketed human therapeutics, the thiomuracins have a low propensity for selecting for antibiotic resistance and confer no measurable cross-resistance to antibiotics in clinical use.


Asunto(s)
Antibacterianos/farmacología , Factor Tu de Elongación Peptídica/metabolismo , Péptidos/genética , Péptidos/farmacología , Staphylococcus aureus/efectos de los fármacos , Tiazoles/farmacología , Actinomycetales/química , Secuencia de Aminoácidos , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/farmacología , Regulación Bacteriana de la Expresión Génica , Genes Bacterianos , Datos de Secuencia Molecular , Péptidos/química , Péptidos/aislamiento & purificación , Biosíntesis de Proteínas , Staphylococcus aureus/crecimiento & desarrollo , Tiazoles/química , Tiazoles/aislamiento & purificación
15.
J Antimicrob Chemother ; 62(4): 713-9, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18587134

RESUMEN

OBJECTIVES: The aim of this study was to determine the in vitro activity of lipiarmycin against drug-resistant strains of Mycobacterium tuberculosis (MTB) and to establish the resistance mechanism of MTB against lipiarmycin using genetic approaches. METHODS: MIC values were measured against a panel of drug-resistant strains of MTB using the broth microdilution method. Spontaneous lipiarmycin-resistant mutants of MTB were tested for cross-resistance to standard anti-TB drugs, and their rpoB and rpoC genes were sequenced to identify mutations. RESULTS: Lipiarmycin exhibited excellent inhibitory activity against multidrug-resistant strains of MTB with MIC values of <0.1 mg/L. Sequence analysis of the rpoB and rpoC genes from spontaneous lipiarmycin-resistant mutants of MTB revealed that missense mutations in these genes caused resistance to lipiarmycin. Although both lipiarmycin and rifampicin are known to inhibit the bacterial RNA polymerase, the sites of mutation in the rpoB gene were found to be different in MTB strains resistant to these inhibitors. Whereas all six rifampicin-resistant MTB strains tested had mutation in the 81 bp hotspot region of the rpoB gene spanning codons 507-533, 16 of 18 lipiarmycin-resistant strains exhibited mutation between codons 977 and 1150. The remaining two lipiarmycin-resistant strains had mutation in the rpoC gene. CONCLUSIONS: Lipiarmycin has excellent bactericidal activity against MTB and lacks cross-resistance to standard anti-TB drugs. Furthermore, rifampicin-resistant strains remained fully susceptible to lipiarmycin, and none of the lipiarmycin-resistant MTB strains became resistant to rifampicin, highlighting the lack of cross-resistance.


Asunto(s)
Aminoglicósidos/farmacología , Antituberculosos/farmacología , ARN Polimerasas Dirigidas por ADN/antagonistas & inhibidores , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Adaptación Biológica , Secuencia de Aminoácidos , Sustitución de Aminoácidos/genética , Proteínas Bacterianas/genética , Análisis Mutacional de ADN , ADN Bacteriano/química , ADN Bacteriano/genética , Fidaxomicina , Humanos , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana , Modelos Moleculares , Datos de Secuencia Molecular , Mutación Missense , Mycobacterium tuberculosis/aislamiento & purificación , Rifampin/farmacología , Alineación de Secuencia , Análisis de Secuencia de ADN
16.
Cell Host Microbe ; 22(1): 25-37.e6, 2017 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-28704649

RESUMEN

Host factors in the intestine help select for bacteria that promote health. Certain commensals can utilize mucins as an energy source, thus promoting their colonization. However, health conditions such as inflammatory bowel disease (IBD) are associated with a reduced mucus layer, potentially leading to dysbiosis associated with this disease. We characterize the capability of commensal species to cleave and transport mucin-associated monosaccharides and identify several Clostridiales members that utilize intestinal mucins. One such mucin utilizer, Peptostreptococcus russellii, reduces susceptibility to epithelial injury in mice. Several Peptostreptococcus species contain a gene cluster enabling production of the tryptophan metabolite indoleacrylic acid (IA), which promotes intestinal epithelial barrier function and mitigates inflammatory responses. Furthermore, metagenomic analysis of human stool samples reveals that the genetic capability of microbes to utilize mucins and metabolize tryptophan is diminished in IBD patients. Our data suggest that stimulating IA production could promote anti-inflammatory responses and have therapeutic benefits.


Asunto(s)
Indoles/metabolismo , Indoles/farmacología , Inflamación/metabolismo , Mucosa Intestinal/microbiología , Peptostreptococcus/metabolismo , Simbiosis , Animales , Antiinflamatorios/farmacología , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Bacteroides/genética , Bacteroides/metabolismo , Clostridiales/genética , Clostridiales/metabolismo , Colon/microbiología , Colon/patología , Citocinas/metabolismo , Disbiosis/metabolismo , Humanos , Enfermedades Inflamatorias del Intestino , Mucosa Intestinal/lesiones , Mucosa Intestinal/metabolismo , Intestinos/microbiología , Ratones , Mucina 2/genética , Mucina 2/metabolismo , Mucinas/genética , Mucinas/metabolismo , Organoides
18.
J Med Chem ; 59(14): 6920-8, 2016 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-27355833

RESUMEN

Synthetic studies of the antimicrobial secondary metabolite thiomuracin A (1) provided access to analogues in the Northern region (C2-C10). Selective hydrolysis of the C10 amide of lead compound 2 and subsequent derivatization led to novel carbon- and nitrogen-linked analogues (e.g., 3) which improved antibacterial potency across a panel of Gram-positive organisms. In addition, congeners with improved physicochemical properties were identified which proved efficacious in murine sepsis and hamster C. difficile models of disease. Optimal efficacy in the hamster model of C. difficile was achieved with compounds that possessed both potent antibacterial activity and high aqueous solubility.


Asunto(s)
Antibacterianos/farmacología , Clostridioides difficile/efectos de los fármacos , Infecciones por Clostridium/tratamiento farmacológico , Péptidos Cíclicos/farmacología , Tiazoles/farmacología , Animales , Antibacterianos/síntesis química , Antibacterianos/química , Cricetinae , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Ratones , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Estructura Molecular , Péptidos Cíclicos/síntesis química , Péptidos Cíclicos/química , Solubilidad , Relación Estructura-Actividad , Tiazoles/síntesis química , Tiazoles/química
20.
Nat Commun ; 6: 8613, 2015 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-26456460

RESUMEN

FR171456 is a natural product with cholesterol-lowering properties in animal models, but its molecular target is unknown, which hinders further drug development. Here we show that FR171456 specifically targets the sterol-4-alpha-carboxylate-3-dehydrogenase (Saccharomyces cerevisiae--Erg26p, Homo sapiens--NSDHL (NAD(P) dependent steroid dehydrogenase-like)), an essential enzyme in the ergosterol/cholesterol biosynthesis pathway. FR171456 significantly alters the levels of cholesterol pathway intermediates in human and yeast cells. Genome-wide yeast haploinsufficiency profiling experiments highlight the erg26/ERG26 strain, and multiple mutations in ERG26 confer resistance to FR171456 in growth and enzyme assays. Some of these ERG26 mutations likely alter Erg26 binding to FR171456, based on a model of Erg26. Finally, we show that FR171456 inhibits an artificial Hepatitis C viral replicon, and has broad antifungal activity, suggesting potential additional utility as an anti-infective. The discovery of the target and binding site of FR171456 within the target will aid further development of this compound.


Asunto(s)
3-Hidroxiesteroide Deshidrogenasas/antagonistas & inhibidores , Antifúngicos/química , Colesterol/análogos & derivados , Proteínas de Saccharomyces cerevisiae/antagonistas & inhibidores , Saccharomyces cerevisiae/genética , 3-Hidroxiesteroide Deshidrogenasas/genética , Candida albicans , Colesterol/química , Farmacorresistencia Fúngica/genética , Ergosterol/biosíntesis , Mutación , Proteínas de Saccharomyces cerevisiae/genética
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