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1.
Brief Bioinform ; 24(2)2023 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-36764832

RESUMEN

Molecular docking is a structure-based and computer-aided drug design approach that plays a pivotal role in drug discovery and pharmaceutical research. AutoDock is the most widely used molecular docking tool for study of protein-ligand interactions and virtual screening. Although many tools have been developed to streamline and automate the AutoDock docking pipeline, some of them still use outdated graphical user interfaces and have not been updated for a long time. Meanwhile, some of them lack cross-platform compatibility and evaluation metrics for screening lead compound candidates. To overcome these limitations, we have developed Dockey, a flexible and intuitive graphical interface tool with seamless integration of several useful tools, which implements a complete docking pipeline covering molecular sanitization, molecular preparation, paralleled docking execution, interaction detection and conformation visualization. Specifically, Dockey can detect the non-covalent interactions between small molecules and proteins and perform cross-docking between multiple receptors and ligands. It has the capacity to automatically dock thousands of ligands to multiple receptors and analyze the corresponding docking results in parallel. All the generated data will be kept in a project file that can be shared between any systems and computers with the pre-installation of Dockey. We anticipate that these unique characteristics will make it attractive for researchers to conduct large-scale molecular docking without complicated operations, particularly for beginners. Dockey is implemented in Python and freely available at https://github.com/lmdu/dockey.


Asunto(s)
Diseño de Fármacos , Proteínas , Simulación del Acoplamiento Molecular , Proteínas/metabolismo , Descubrimiento de Drogas , Ligandos , Programas Informáticos
2.
Nature ; 563(7733): 666-670, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30464340

RESUMEN

Quantum states of mechanical motion can be important resources for quantum information, metrology and studies of fundamental physics. Recent demonstrations of superconducting qubits coupled to acoustic resonators have opened up the possibility of performing quantum operations on macroscale motional modes1-3, which can act as long-lived quantum memories or transducers. In addition, they can potentially be used to test decoherence mechanisms in macroscale objects and other modifications to standard quantum theory4,5. Many of these applications call for the ability to create and characterize complex quantum states, such as states with a well defined phonon number, also known as phonon Fock states. Such capabilities require fast quantum operations and long coherence times of the mechanical mode. Here we demonstrate the controlled generation of multi-phonon Fock states in a macroscale bulk acoustic-wave resonator. We also perform Wigner tomography and state reconstruction to highlight the quantum nature of the prepared states6. These demonstrations are made possible by the long coherence times of our acoustic resonator and our ability to selectively couple a superconducting qubit to individual phonon modes. Our work shows that circuit quantum acoustodynamics7 enables sophisticated quantum control of macroscale mechanical objects and opens up the possibility of using acoustic modes as quantum resources.

3.
Appl Microbiol Biotechnol ; 108(1): 222, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38372782

RESUMEN

Pseudomonas aeruginosa is a common opportunistic pathogen with growing resistance and presents heightened treatment challenges. Quorum sensing (QS) is a cell-to-cell communication system that contributes to the production of a variety of virulence factors and is also related to biofilm formation of P. aeruginosa. Compared to traditional antibiotics which kill bacteria directly, the anti-virulence strategy by targeting QS is a promising strategy for combating pseudomonal infections. In this study, the QS inhibition potential of the compounds derived from the Traditional Chinese Medicines was evaluated by using in silico, in vitro, and in vivo analyses. The results showed that psoralen, a natural furocoumarin compound derived from Psoralea corylifolia L., was capable of simultaneously inhibiting the three main QS regulators, LasR, RhlR, and PqsR of P. aeruginosa. Psoralen had no bactericidal activity but could widely inhibit the production of extracellular proteases, pyocyanin, and biofilm, and the cell motilities of the model and clinical P. aeruginosa strains. RNA-sequencing and quantitative PCR analyses further demonstrated that a majority of QS-activated genes in P. aeruginosa were suppressed by psoralen. The supplementation of psoralen could protect Caenorhabditis elegans from P. aeruginosa challenge, especially for the hypervirulent strain PA14. Moreover, psoralen showed synergistic antibacterial effects with polymyxin B, levofloxacin, and kanamycin. In conclusions, this study identifies the anti-QS and antibiofilm effects of psoralen against P. aeruginosa strains and sheds light on the discovery of anti-pseudomonal drugs among Traditional Chinese Medicines. KEY POINTS: • Psoralen derived from Psoralea corylifolia L. inhibits the virulence-related phenotypes of P. aeruginosa. • Psoralen simultaneously targets the three core regulators of P. aeruginosa QS system and inhibits the expression of a large part of downstream genes. • Psoralen protects C. elegans from P. aeruginosa challenge and enhances the susceptibility of P. aeruginosa to antibiotics.


Asunto(s)
Fabaceae , Furocumarinas , Infecciones por Pseudomonas , Animales , Pseudomonas aeruginosa/genética , Ficusina/farmacología , Percepción de Quorum , Virulencia , Caenorhabditis elegans , Infecciones por Pseudomonas/tratamiento farmacológico , Furocumarinas/farmacología , Antibacterianos/farmacología
4.
Chembiochem ; 24(16): e202300180, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37183575

RESUMEN

The clustered regularly interspaced short palindromic repeat (CRISPR)/associated protein 9 (CRISPR/Cas9) system has been widely explored for the precise manipulation of target DNA and has enabled efficient genomic editing in cells. Recently, CRISPR/Cas9 has shown promising potential in biomedical applications, including disease treatment, transcriptional regulation and genome-wide screening. Despite these exciting achievements, efficient and controlled delivery of the CRISPR/Cas9 system has remained a critical obstacle to its further application. Herein, we elaborate on the three delivery forms of the CRISPR/Cas9 system, and discuss the composition, advantages and limitations of these forms. Then we provide a comprehensive overview of the carriers of the system, and focus on the nonviral nanocarriers in chemical methods that facilitate efficient and controlled delivery of the CRISPR/Cas9 system. Finally, we discuss the challenges and prospects of the delivery methods of the CRISPR/Cas9 system in depth, and propose strategies to address the intracellular and extracellular barriers to delivery in clinical applications.


Asunto(s)
Sistemas CRISPR-Cas , Polímeros , Sistemas CRISPR-Cas/genética , Polímeros/metabolismo , Edición Génica , Proteína 9 Asociada a CRISPR/genética , Proteína 9 Asociada a CRISPR/metabolismo , Lípidos
5.
Phys Rev Lett ; 130(13): 133604, 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-37067306

RESUMEN

Recently, solid-state mechanical resonators have become a platform for demonstrating nonclassical behavior of systems involving a truly macroscopic number of particles. Here, we perform the most macroscopic quantum test in a mechanical resonator to date, which probes the validity of quantum mechanics by ruling out a classical description at the microgram mass scale. This is done by a direct measurement of the Wigner function of a high-overtone bulk acoustic wave resonator mode, monitoring the gradual decay of negativities over tens of microseconds. While the obtained macroscopicity of µ=11.3 is on par with state-of-the-art atom interferometers, future improvements of mode geometry and coherence times could test the quantum superposition principle at unprecedented scales and also place more stringent bounds on spontaneous collapse models.

6.
Arch Microbiol ; 205(3): 91, 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36781487

RESUMEN

A novel actinobacterium with antimicrobial activity, designated strain H16431T, was isolated from a sediment sample collected from Dianchi Lake, Yunnan Province, PR China. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain H16431T was most closely related to Nonomuraea rhizosphaerae CGMCC 4.7431T and Nonomuraea guangzhouensis CGMCC 4.7101T (98.1% similarity), but formed a monophyletic clade with Nonomuraea ceibae KCTC 39826T (98.0% similarity). Phylogenomic analysis based on whole-genome sequence showed that strain H16431T formed a separate clade within the genus Nonomuraea. The average nucleotide identity, average amino acid identity, and digital DNA-DNA hybridization values between strain H16431T and its closely related Nonomuraea species were 80.0-81.5%, 71.2-74.6%, and 23.2-25.0%, respectively, which were significantly lower than the widely accepted species-defined threshold. The DNA G + C content was 70.2% based on the whole-genome sequence. The menaquinones were identified as MK-9(H4), MK-9(H6), and MK-9(H2). The major fatty acids were iso-C16:0, 10 methyl-C17:0, and iso-C16:0 2OH. The phospholipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, and phosphatidylinositol. These chemotaxonomic characteristics were corresponded to those of the genus Nonomuraea. On the basis of the taxonomic evidence, strain H16431T represents a novel species of the genus Nonomuraea, for which the name Nonomuraea sediminis sp. nov. is proposed. The type strain is H16431T (=JCM 34852T=CICC 25119T).


Asunto(s)
Actinomycetales , Antiinfecciosos , Fosfatidiletanolaminas , Filogenia , ARN Ribosómico 16S/genética , Lagos , ADN Bacteriano/genética , China , Técnicas de Tipificación Bacteriana , Análisis de Secuencia de ADN , Microbiología del Suelo , Ácido Diaminopimélico/química , Actinomycetales/genética , Fosfolípidos/química , Ácidos Grasos/química , Vitamina K 2/química
7.
Arch Microbiol ; 205(6): 230, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37162591

RESUMEN

Mycobacterium tuberculosis, the ancient master of causing tuberculosis, is one of the most successful pathogens capable of persistently colonizing host lungs. The EsxB (CFP-10) of ESX-1 system and PPE68 of the PPE family contribute to the virulence of M. tuberculosis. However, the virulence potential and pathogenetic characteristics of these two proteins during M. tuberculosis infection remain unclear. In this study, two prokaryotic expression plasmids for EsxB or PPE68 of M. tuberculosis were constructed and the recombinant proteins His-EsxB or His-PPE68 were purified. The proteome and transcriptome of MH-S cells treated with His-EsxB or His-PPE68 were explored, followed by validating the expression of the identified differentially expressed genes (DEGs) using quantitative PCR. A total of 159/439 specific proteins or 633/1117 DEGs were obtained between control and His-EsxB or His-PPE68 treated groups in the MH-S proteomes and transcriptomes. Additionally, 37/60 signal pathways were predicted in the His-EsxB or His-PPE68 treated groups and "Cytokine-cytokine receptor interaction" was the most represented pathway. Furthermore, the expression of the DEGs (IL-1ß, IL-6, and TNF-α) was significantly upregulated, suggesting that these DEGs contributed to the host response during EsxB or PPE68 treatment. These findings provide detailed information on developing an effective intervention strategy to control M. tuberculosis infection.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Humanos , Mycobacterium tuberculosis/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Factores de Virulencia/genética , Multiómica
8.
Curr Microbiol ; 81(1): 7, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37962701

RESUMEN

A novel actinomycete strain, designated H11425T, was isolated from a sediment sample collected from Baihua Lake, Guizhou Province, PR China, and a polyphasic approach was employed to determine its taxonomic position. 16S rRNA gene sequence comparisons showed that strain H11425T is most closely related to Pseudonocardia sulfidoxydans JCM 10411T (97.9%) and Pseudonocardia kunmingensis JCM 32122T (97.8%). Both of phylogenetic analysis based on 16S rRNA gene sequence and phylogenomic analysis based on whole-genome sequence showed that strain H11425T formed a separate clade within the genus Pseudonocardia. The draft genome had a length of 8,059,576 bp with a G + C content of 74.5%. The average nucleotide identity, average amino acid identity, and digital DNA-DNA hybridization values between strain H11425T and its closely related Pseudonocardia species were 76.8-79.0%, 64.8-69.9% and 21.7-23.3%, respectively, which were significantly lower than the widely accepted species-defined threshold. Strain H11425T contained meso-diaminopimelic acid, arabinose, galactose, glucose and ribose in its whole-cell hydrolysates. Mycolic acids were absent. The menaquinone was identifed as MK-8(H4). The phospholipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidylcholine, an unknown phospholipid and four unidentified aminophospholipids. The major fatty acids were iso-C16:0, iso-C14:0, iso H-C16:1 and iso-C16:0 2OH. On the basis of the taxonomic evidence, strain H11425T represents a novel species of the genus Pseudonocardia, for which the name Pseudonocardia lacus sp. nov. is proposed. The type strain is H11425T (= JCM 34851T = CICC 25118T).


Asunto(s)
Actinobacteria , Actinomycetales , Actinobacteria/genética , Pseudonocardia , Fosfatidiletanolaminas , Lagos , Filogenia , ARN Ribosómico 16S/genética , Fosfolípidos , ADN
9.
J Am Chem Soc ; 144(10): 4667-4677, 2022 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-35254064

RESUMEN

Constructing artificial dynamic architectures inside cells to rationally interfere with organelles is emerging as an efficient strategy to regulate the behaviors and fate of cells, thus providing new routes for therapeutics. Herein, we develop an intracellular K+-mediating dynamic assembly of DNA tetrahedrons inside cells, which realizes efficient mitochondrial interference and consequent regulation on the energy metabolism of living cells. In the designer DNA tetrahedron, one vertex was modified with triphenylphosphine (TPP) for mitochondrial targeting, and the other three vertexes were tethered with guanine-rich sequences that could realize K+-mediating formation of intermolecular G-quadruplexes, which consequently led to the assembly of DNA tetrahedrons to form aggregates in the cytoplasm. The DNA aggregates specially targeted mitochondria and served as a polyanionic barrier for substance communication, thus generating a significant inhibition effect on the aerobic respiration function of mitochondria and the associated glycolysis process, which consequently reduced the production of intracellular adenosine triphosphate (ATP). The lack of ATP impeded the formation of lamellipodium that was essential for the movement of cells, consequently resulting in a significant inhibitory effect on cell migration. Remarkably, the migration capacity was suppressed by as high as 50% for cancer cells. This work provides a new strategy for the manipulation of organelles via the endogenous molecule-mediating dynamic assembly of exogenous artificial architectures inside living cells, which is envisioned to have great potential in precise biomedicine.


Asunto(s)
Mitocondrias , Nanoestructuras , Adenosina Trifosfato/metabolismo , ADN/metabolismo , Metabolismo Energético , Mitocondrias/metabolismo
10.
Appl Environ Microbiol ; 88(12): e0059222, 2022 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-35638844

RESUMEN

Bacterial species in the polymicrobial community evolve interspecific interaction relationships to adapt to the survival stresses imposed by neighbors or environmental cues. Pseudomonas aeruginosa and Staphylococcus aureus are two common bacterial pathogens frequently coisolated from patients with burns and respiratory disease. Whether the application of commonly used antibiotics influences the interaction dynamics of the two species still remains largely unexplored. By performing a series of on-plate competition assays and RNA sequencing-based transcriptional profiling, we showed that the presence of the cephalosporin antibiotic cefotaxime or the quinolone antibiotic levofloxacin at subinhibitory concentration contributes to selecting P. aeruginosa from the coculture with S. aureus by modulating the quorum-sensing (QS) system of P. aeruginosa. Specifically, a subinhibitory concentration of cefotaxime promotes the growth suppression of S. aureus by P. aeruginosa in coculture. This process may be related to the increased production of the antistaphylococcal molecule pyocyanin and the expression of lasR, which is the central regulatory gene of the P. aeruginosa QS hierarchy. On the other hand, subinhibitory concentrations of levofloxacin decrease the competitive advantage of P. aeruginosa over S. aureus by inhibiting the growth and the las QS system of P. aeruginosa. However, pqs signaling of P. aeruginosa can be activated instead to overcome S. aureus. Therefore, this study contributes to understanding the interaction dynamics of P. aeruginosa and S. aureus during antibiotic treatment and provides an important basis for studying the pathogenesis of polymicrobial infections. IMPORTANCE Increasing evidence has demonstrated the polymicrobial characteristics of most chronic infections, and the frequent communications among bacterial pathogens result in many difficulties for clinical therapy. Exploring bacterial interspecific interaction during antibiotic treatment is an emerging endeavor that may facilitate the understanding of polymicrobial infections and the optimization of clinical therapies. Here, we investigated the interaction of cocultured P. aeruginosa and S. aureus with the intervention of commonly used antibiotics in clinic. We found that the application of subinhibitory concentrations of cefotaxime and levofloxacin can select P. aeruginosa in coculture with S. aureus by modulating P. aeruginosa QS regulation to enhance the production of antistaphylococcal metabolites in different ways. This study emphasizes the role of the QS system in the interaction of P. aeruginosa with other bacterial species and provides an explanation for the persistence and enrichment of P. aeruginosa in patients after antibiotic treatment and a reference for further clinical therapy.


Asunto(s)
Coinfección , Infecciones por Pseudomonas , Infecciones Estafilocócicas , Antibacterianos/metabolismo , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Cefotaxima/farmacología , Técnicas de Cocultivo , Humanos , Levofloxacino/metabolismo , Levofloxacino/farmacología , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/metabolismo , Percepción de Quorum , Staphylococcus aureus/fisiología
11.
Artículo en Inglés | MEDLINE | ID: mdl-36129751

RESUMEN

A novel actinobacterium, designated strain H8750T, was isolated from sediment sampled at Lugu Lake, southwest PR China and its polyphasic taxonomy was studied. Strain H8750T produced well-developed substrate mycelium, and formed club-shaped and hooked structures borne on the tip of the aerial mycelia. It contained meso-diaminopimelic, glucose, ribose and madurose in whole-cell hydrolysates. The predominant menaquinones were MK-9(H4), MK-9(H2) and MK-9(H6). The phospholipid profile contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, unidentified phospholipids and unidentified aminophospholipids. The major fatty acid (>10 %) were cis 9 C17 : 1, iso-C16 : 0 and C15 : 0. The DNA G+C content was 69.7 mol% based on the whole genome sequence. Phylogenetic analysis based on 16S rRNA gene and whole-genome sequences indicated that strain H8750T was closely related to Acrocarpospora macrocephala JCM 10982T (98.0 %), Acrocarpospora pleiomorpha JCM 10983T (97.9 %) and Acrocarpospora phusangensis DSM 45867 T (97.8 %) and formed a monophyletic clade within the genus Acrocarpospora in the phylogenetic trees. The average nucleotide identity and digital DNA-DNA hybridization values between strain H8750T and its closely related Acrocarpospora species were 79.8~87.2 % and 25.9~28.0 %, respectively, which showed that it belonged to a distinct species. Furthermore, the morphological and phenotypic characteristics allowed the isolate to be differentiated from its closely related species. Therefore, it is concluded that strain H8750T can be classified as representing a novel species of the genus Acrocarpospora, for which the name Acrocarpospora catenulata sp. nov. is proposed. The type strain is H8750T (=JCM 34849T=CICC 25116T). Moreover, based on the gene prediction results, strain H8750T may have the genetic potential to synthesize many new secondary metabolites, which further increases its bioactive value.


Asunto(s)
Actinomycetales , Fosfatidiletanolaminas , Técnicas de Tipificación Bacteriana , Composición de Base , Cardiolipinas , ADN Bacteriano/genética , Ácidos Grasos/química , Glucosa , Lagos/análisis , Nucleótidos , Fosfolípidos/química , Filogenia , ARN Ribosómico 16S/genética , Ribosa , Análisis de Secuencia de ADN , Microbiología del Suelo , Vitamina K 2/química
12.
Ann Clin Microbiol Antimicrob ; 21(1): 38, 2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36038932

RESUMEN

BACKGROUND: Antibiotic-resistant Gram-negative bacteria are becoming a major public health threat such as the important opportunistic pathogen Pseudomonas aeruginosa (P. aeruginosa). The present study investigated enhancement of the linezolid spectrum, which is normally used to treat Gram-positive bacteria, at inhibiting P. aeruginosa growth. METHODS: The checkerboard test or time-kill assay were carried out to determine the antibacterial effects of linezolid in cooperation with polymyxin B octapeptide PBOP (LP) against P. aeruginosa based on in vitro model. The protective effect of LP against P. aeruginosa infection was assessed based on a Caenorhabditis elegans (C. elegans) model. RESULTS: The synergistic activity and antibacterial effects were significantly increased against P. aeruginosa by LP treatment, while linezolid and PBOP as monotherapies exhibited no remarkably bactericidal activity against the clinical strains. Additionally, LP treatment modified biofilm production, morphology, swimming motility of P. aeruginosa, and protected C. elegans from P. aeruginosa infection. CONCLUSIONS: This research demonstrates that LP combination has significant synergistic activity against P. aeruginosa, and PBOP is potential to be an activity enhancer. Notably, this strategy improved the antibacterial activity spectrum of linezolid and other anti-Gram-positive agents and represents an effective choice to surmount the antibiotic resistance of bacteria in the long term.


Asunto(s)
Caenorhabditis elegans , Pseudomonas aeruginosa , Animales , Antibacterianos/farmacología , Sinergismo Farmacológico , Humanos , Linezolid/farmacología , Pruebas de Sensibilidad Microbiana , Polimixina B/análogos & derivados , Polimixina B/farmacología
13.
BMC Vet Res ; 18(1): 114, 2022 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-35331229

RESUMEN

BACKGROUND: Trueperella pyogenes and Pseudomonas aeruginosa are two important bacterial pathogens closely relating to the occurrence and development of forest musk deer respiratory purulent disease. Although T. pyogenes is the causative agent of the disease, the subsequently invaded P. aeruginosa will predominate the infection by producing a substantial amount of quorum-sensing (QS)-controlled virulence factors, and co-infection of them usually creates serious difficulties for veterinary treatment. In order to find a potential compound that targets both T. pyogenes and P. aeruginosa, the antibacterial and anti-virulence capacities of 55 compounds, which have similar core structure to the signal molecules of P. aeruginosa QS system, were tested in this study by performing a series of in vitro screening experiments. RESULTS: We identified that furazolidone could significantly reduce the cell densities of T. pyogenes in mono-culture or in the co-culture with P. aeruginosa. Although the growth of P. aeruginosa could also be moderately inhibited by furazolidone, the results of phenotypic identification and transcriptomic analysis further revealed that sub-inhibitory furazolidone had remarkable inhibitory effect on the biofilm production, motility, and QS system of P. aeruginosa. Moreover, furazolidone could efficiently protect Caenorhabditis elegans models from P. aeruginosa infection under both fast-killing and slow-killing conditions. CONCLUSIONS: This study reports the antibacterial and anti-virulence abilities of furazolidone on T. pyogenes and P. aeruginosa, and provides a promising strategy and molecular basis for the development of novel anti-infectious drugs to dealing with forest musk deer purulent disease, or other diseases caused by T. pyogenes and P. aeruginosa co-infection.


Asunto(s)
Ciervos , Pseudomonas aeruginosa , Animales , Antibacterianos/farmacología , Biopelículas , Ciervos/microbiología , Furazolidona/farmacología , Percepción de Quorum , Virulencia , Factores de Virulencia
14.
Environ Microbiol ; 23(12): 7432-7444, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33723911

RESUMEN

Interspecific interaction happens frequently among bacterial species and can promote the colonization of polymicrobial community in various environments. However, it is not clear whether the intervention of antibiotics, which is a common therapeutic method for infectious disease, will influence the interacting dynamics of different pathogenic bacteria. By using the frequently co-isolated bacteria Pseudomonas aeruginosa and Staphylococcus aureus as models, here we identify an antibiotic-determined mutual invasion relationship between bacterial pathogens. We show that although P. aeruginosa has a significant intrinsic competitive advantage over S. aureus by producing the quorum-sensing (QS)-controlled anti-staphylococcal molecules, methicillin-resistant S. aureus (MRSA) can inhibit neighbouring P. aeruginosa in the presence of subinhibitory aminoglycoside antibiotics (e.g. streptomycin) to P. aeruginosa. Importantly, subinhibitory streptomycin decreases the expression of QS-regulated genes in P. aeruginosa and thus relieves the survival stress of MRSA brought by P. aeruginosa. On the other side, the iron-uptake systems and pathogenicity of MRSA can be enhanced by the extracellular products of streptomycin-treated P. aeruginosa. Therefore, this study provides an explanation for the substitution of dominant species and persistent coexistence of bacterial pathogens in the host with repeated antibiotic therapies and contributes to further understanding the pathogenesis of chronic polymicrobial infections.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones por Pseudomonas , Infecciones Estafilocócicas , Antibacterianos/metabolismo , Bacterias/genética , Humanos , Staphylococcus aureus Resistente a Meticilina/genética , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/metabolismo , Percepción de Quorum , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo
15.
Bioorg Chem ; 114: 105108, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34175721

RESUMEN

A series of novel 2-oxo-(1-oxo-2,8-diazaspiro[4.5]decane-8-yl)ethylpiperidine carboxamide derivatives were designed, synthesized and characterized by 1H NMR, 13C NMR and HRMS spectroscopy. All eighteen newly prepared compounds were evaluated for their inhibition against chitin synthase (CHS) and antifungal activities in vitro. The enzyme assay revealed that compound 5h showed excellent inhibitory activity against CHS with IC50 value of 0.10 mM, and the compounds 5b, 5d and 5q showed good inhibition against chitin synthase with IC50 values of 0.13 mM, 0.18 mM and 0.15 mM, respectively, while IC50 value of ployoxin B was 0.08 mM. Meanwhile, the others of these compounds exhibited moderate inhibition potency against chitin synthase. The antifungal assay showed compound 5h had excellent antifungal activity compared with the control drugs fluconazole and polyoxin B against these tested strains including C. albicans, A. fumigatus, C. neoformans and A. flavus. Its excellent antifungal activity was consistent with its excellent chitin synthase inhibition. Compound 5k and 5l against C. albicans were comparable with fluconazole, and they showed strong antifungal potency against A. flavus with MIC values of 0.07 mmol/L and 0.13 mmol/L respectively. Compound 5m had similar MIC value against A. fumigatus to fluconazole. The phenomenon that compounds 5b, 5d and 5q that showed good enzymatic inhibition didn't exert good antifungal activity, while compounds 5k, 5l and 5m that showed moderate chitin synthase inhibition exhibited excellent antifungal activity was discussed. Furthermore, the trial of drug combination showed that compounds had synergistic effects or additive effects with fluconazole against tested fungi which also verified that these designed compounds targeted different targets from that of fluconazole. Additionally, the antibacterial trial showed that all synthesized compounds had little potency against tested bacteria strains. These results indicated that the designed compounds were potential chitin synthase inhibitors and had selectively antifungal activities.


Asunto(s)
Antifúngicos/farmacología , Compuestos Aza/farmacología , Quitina Sintasa/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Piperidinas/farmacología , Compuestos de Espiro/farmacología , Antifúngicos/síntesis química , Antifúngicos/química , Aspergillus/efectos de los fármacos , Compuestos Aza/síntesis química , Compuestos Aza/química , Candida/efectos de los fármacos , Quitina Sintasa/metabolismo , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Piperidinas/química , Saccharomyces cerevisiae/enzimología , Compuestos de Espiro/síntesis química , Compuestos de Espiro/química , Relación Estructura-Actividad
16.
Arch Microbiol ; 202(8): 2181-2188, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32519021

RESUMEN

Bacterial quorum sensing (QS) system regulates the production of most costly but sharable extracellular products (public goods) in a growth-phase-dependent manner, and the development of this energy-intensive process is susceptible to environmental changes. However, the role of nutrient factors in dominating the QS-mediated cooperative interaction and intracellular metabolism still remains less understood. Here we studied the performance of QS system by growing Pseudomonas aeruginosa under different nutrient and culture conditions. The results of comparative-transcriptomic analyses revealed that carbon source-limitation was the main factor suppressing the activation of QS system, and a substantial number of public-good-encoding genes were induced when phosphorus is limiting in short-term culture. By contrast, although the QS regulation of P. aeruginosa in all the cultures was generally decreased along with the enrichment of QS-deficient individuals during evolution, limitation of different nutrient factors had discrepant effects in directing the formation of population structure by coordinating the production of public goods and primary metabolism, especially the starch and sucrose metabolism. These findings demonstrate the pleiotropy of QS regulation in balancing the development of cooperative behavior and metabolism, and provide a reference for further understanding the role of QS system in causing persistent infections.


Asunto(s)
Pseudomonas aeruginosa/fisiología , Percepción de Quorum/fisiología , Medios de Cultivo/farmacología , Nutrientes/farmacología , Pseudomonas aeruginosa/efectos de los fármacos
17.
Int J Syst Evol Microbiol ; 70(5): 3309-3315, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32375928

RESUMEN

A novel actinobacterium, designated strain H14505T, was isolated from a soil sample collected in Hong Yuan, Sichuan, southwest PR China. The temperature, pH and NaCl ranges for growth were determined to be 15-35 °C (optimum, 28 °C), 6.0-8.0 (optimum, pH 7.0) and 0-2 % (w/v; optimum without NaCl), respectively. The polar lipdis detected for strain H14505T were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, glycolipid and four unidentified lipids. The predominant menaquinones of strain H14505T were MK-9(H4) and MK-9(H6), and the prevalent fatty acids (>10 %) were C18 : 1 ω9c, C17 : 1 ω8c, summed feature 5 (anteiso-C18 : 0/ C18 : 2 ω6,9c) and C16 : 0. Phylogenetic analysis based on 16S rRNA gene and whole-genome sequences indicated that strain H14505T showed high similarity to Catellatospora vulcania NEAU-JM1T (99.0 %) and Catellatospora paridis NEAU-CL2T (99.0 %), and formed a monophyletic clade within the the genus Catellatospora in the phylogenetic trees. However, the average nucleotide indentity and DNA-DNA hybridization values between strain H14505T and closely related Catellatospora species showed that it belonged to a distinct species. Furthermore, the results of morphological, physiological and biochemical tests allowed further phenotypic differentiation of strain H14505T from its closest relatives. Thus, it is proposed that strain H14505T represents a novel species of the genus Catellatospora, for which the name Catellatospora sichuanensis sp. nov. is proposed. The type strain of Catellatospora sichuanensis is H14505T (=JCM 32394T=CICC 11042T).


Asunto(s)
Micromonosporaceae/clasificación , Filogenia , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Micromonosporaceae/aislamiento & purificación , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
18.
BMC Biol ; 17(1): 20, 2019 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-30841874

RESUMEN

BACKGROUND: Microbial communities are susceptible to the public goods dilemma, whereby individuals can gain an advantage within a group by utilizing, but not sharing the cost of producing, public goods. In bacteria, the development of quorum sensing (QS) can establish a cooperation system in a population by coordinating the production of costly and sharable extracellular products (public goods). Cooperators with intact QS system and robust ability in producing public goods are vulnerable to being undermined by QS-deficient defectors that escape from QS but benefit from the cooperation of others. Although microorganisms have evolved several mechanisms to resist cheating invasion in the public goods game, it is not clear why cooperators frequently coexist with defectors and how they form a relatively stable equilibrium during evolution. RESULTS: We show that in Pseudomonas aeruginosa, QS-directed social cooperation can select a conditional defection strategy prior to the emergence of QS-mutant defectors, depending on resource availability. Conditional defectors represent a QS-inactive state of wild type (cooperator) individual and can invade QS-activated cooperators by adopting a cheating strategy, and then revert to cooperating when there are abundant nutrient supplies irrespective of the exploitation of QS-mutant defector. Our mathematical modeling further demonstrates that the incorporation of conditional defection strategy into the framework of iterated public goods game with sound punishment mechanism can lead to the coexistence of cooperator, conditional defector, and defector in a rock-paper-scissors dynamics. CONCLUSIONS: These findings highlight the importance of behavioral heterogeneity in stabilizing the population structure and provide a potential reasonable explanation for the maintenance and evolution of cooperation in microbial communities.


Asunto(s)
Evolución Biológica , Modelos Biológicos , Pseudomonas aeruginosa/fisiología , Percepción de Quorum
19.
Phys Rev Lett ; 123(25): 250501, 2019 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-31922763

RESUMEN

Hybrid quantum systems in which acoustic resonators couple to superconducting qubits are promising quantum information platforms. High quality factors and small mode volumes make acoustic modes ideal quantum memories, while the qubit-phonon coupling enables the initialization and manipulation of quantum states. We present a scheme for quantum computing with multimode quantum acoustic systems, and based on this scheme, propose a hardware-efficient implementation of a quantum random access memory (QRAM). Quantum information is stored in high-Q phonon modes, and couplings between modes are engineered by applying off-resonant drives to a transmon qubit. In comparison to existing proposals that involve directly exciting the qubit, this scheme can offer a substantial improvement in gate fidelity for long-lived acoustic modes. We show how these engineered phonon-phonon couplings can be used to access data in superposition according to the state of designated address modes-implementing a QRAM on a single chip.

20.
Molecules ; 24(5)2019 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-30862100

RESUMEN

The present study describes an AuPPh3Cl/AgSbF6-catalyzed cascade reaction between amine nucleophiles and alkynoic acids in water. This process proceeds in high step economy with water as the sole coproduct, and leads to the generation of two rings, together with the formation of three new bonds in a single operation. This green cascade process exhibits valuable features such as low catalyst loading, good to excellent yields, high efficiency in bond formation, excellent selectivity, great tolerance of functional groups, and extraordinarily broad substrate scope. In addition, this is the first example of the generation of an indole/thiophene/pyrrole/pyridine/naphthalene/benzene-fused N-heterocycle library through gold catalysis in water from readily available materials. Notably, the discovery of antibacterial molecules from this library demonstrates its high quality and potential for the identification of active pharmaceutical ingredients.


Asunto(s)
Oro/química , Tecnología Química Verde , Compuestos Heterocíclicos/química , Agua/química , Aminas/química , Catálisis , Compuestos Heterocíclicos/síntesis química , Estructura Molecular
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