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1.
J Infect Dis ; 208(2): 271-4, 2013 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-23599311

RESUMEN

HIV-1 dual infection (DI) and CXCR4 (X4) coreceptor usage are associated with accelerated disease progression but frequency and dynamics of coreceptor usage during DI is unknown. Ultradeep sequencing was used to interrogate for DI and infer coreceptor usage in longitudinal blood samples of 102 subjects. At baseline, X4 usage was high (23 subjects harbored X4 variants) and was not associated with infection duration or DI. Coreceptor usage changed over time in 12 of 47 participants, and X4 usage emerged in 4 of 41 monoinfections vs 2 of 5 superinfections (P = .12), suggesting a weak statistical trend toward occurrence of superinfection and acquiring X4 usage.


Asunto(s)
Infecciones por VIH/virología , VIH-1/genética , Adulto , Infecciones por VIH/inmunología , VIH-1/inmunología , Humanos , Masculino , Receptores CXCR4/genética , Receptores CXCR4/inmunología , Análisis de Secuencia de ADN/métodos
2.
Arch Pathol Lab Med ; 146(7): 862-871, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34619755

RESUMEN

CONTEXT.­: Minimal residual disease (MRD) is a major prognostic factor in multiple myeloma, although validated technologies are limited. OBJECTIVE.­: To standardize the performance of the LymphoTrack next-generation sequencing (NGS) assays (Invivoscribe), targeting clonal immunoglobulin rearrangements, in order to reproduce the detection of tumor clonotypes and MRD quantitation in myeloma. DESIGN.­: The quantification ability of the assay was evaluated through serial dilution experiments. Paired samples from 101 patients were tested by LymphoTrack, using Sanger sequencing and EuroFlow's next-generation flow (NGF) assay as validated references for diagnostic and follow-up evaluation, respectively. MRD studies using LymphoTrack were performed in parallel at 2 laboratories to evaluate reproducibility. RESULTS.­: Sensitivity was set as 1.3 tumor cells per total number of input cells. Clonality was confirmed in 99% and 100% of cases with Sanger and NGS, respectively, showing great concordance (97.9%), although several samples had minor discordances in the nucleotide sequence of rearrangements. Parallel NGS was performed in 82 follow-up cases, achieving a median sensitivity of 0.001%, while for NGF, median sensitivity was 0.0002%. Reproducibility of LymphoTrack-based MRD studies (85.4%) and correlation with NGF (R2 > 0.800) were high. Bland-Altman tests showed highly significant levels of agreement between flow and sequencing. CONCLUSIONS.­: Taken together, we have shown that LymphoTrack is a suitable strategy for clonality detection and MRD evaluation, with results comparable to gold standard procedures.


Asunto(s)
Mieloma Múltiple , Humanos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/genética , Neoplasia Residual/diagnóstico , Neoplasia Residual/genética , Reproducibilidad de los Resultados
3.
Nat Commun ; 11(1): 1780, 2020 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-32286267

RESUMEN

A promising new compound class for treating human malaria is the imidazolopiperazines (IZP) class. IZP compounds KAF156 (Ganaplacide) and GNF179 are effective against Plasmodium symptomatic asexual blood-stage infections, and are able to prevent transmission and block infection in animal models. But despite the identification of resistance mechanisms in P. falciparum, the mode of action of IZPs remains unknown. To investigate, we here combine in vitro evolution and genome analysis in Saccharomyces cerevisiae with molecular, metabolomic, and chemogenomic methods in P. falciparum. Our findings reveal that IZP-resistant S. cerevisiae clones carry mutations in genes involved in Endoplasmic Reticulum (ER)-based lipid homeostasis and autophagy. In Plasmodium, IZPs inhibit protein trafficking, block the establishment of new permeation pathways, and cause ER expansion. Our data highlight a mechanism for blocking parasite development that is distinct from those of standard compounds used to treat malaria, and demonstrate the potential of IZPs for studying ER-dependent protein processing.


Asunto(s)
Antimaláricos/farmacología , Plasmodium falciparum/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/metabolismo , Concentración 50 Inhibidora , Espectrometría de Masas , Proteínas Protozoarias/metabolismo , Pirazoles/farmacología , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/metabolismo , Vías Secretoras/efectos de los fármacos
4.
J Cheminform ; 10(1): 6, 2018 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-29464421

RESUMEN

Given that many antifungal medications are susceptible to evolved resistance, there is a need for novel drugs with unique mechanisms of action. Inhibiting the essential proton pump Pma1p, a P-type ATPase, is a potentially effective therapeutic approach that is orthogonal to existing treatments. We identify NSC11668 and hitachimycin as structurally distinct antifungals that inhibit yeast ScPma1p. These compounds provide new opportunities for drug discovery aimed at this important target.

5.
J Med Chem ; 60(15): 6721-6732, 2017 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-28696697

RESUMEN

Naturally derived chemical compounds are the foundation of much of our pharmacopeia, especially in antiproliferative and anti-infective drug classes. Here, we report that a naturally derived molecule called carmaphycin B is a potent inhibitor against both the asexual and sexual blood stages of malaria infection. Using a combination of in silico molecular docking and in vitro directed evolution in a well-characterized drug-sensitive yeast model, we determined that these compounds target the ß5 subunit of the proteasome. These studies were validated using in vitro inhibition assays with proteasomes isolated from Plasmodium falciparum. As carmaphycin B is toxic to mammalian cells, we synthesized a series of chemical analogs that reduce host cell toxicity while maintaining blood-stage and gametocytocidal antimalarial activity and proteasome inhibition. This study describes a promising new class of antimalarial compound based on the carmaphycin B scaffold, as well as several chemical structural features that serve to enhance antimalarial specificity.


Asunto(s)
Antimaláricos/farmacología , Dipéptidos/farmacología , Oligopéptidos/farmacología , Plasmodium falciparum/efectos de los fármacos , Inhibidores de Proteasoma/farmacología , Antimaláricos/síntesis química , Artemisininas/farmacología , Dipéptidos/síntesis química , Diseño de Fármacos , Pruebas de Enzimas , Células Hep G2 , Humanos , Simulación del Acoplamiento Molecular , Oligopéptidos/síntesis química , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/síntesis química , Saccharomyces cerevisiae/efectos de los fármacos
6.
ACS Chem Biol ; 12(2): 422-434, 2017 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-27977118

RESUMEN

Recent advances in cell-based, high-throughput phenotypic screening have identified new chemical compounds that are active against eukaryotic pathogens. A challenge to their future development lies in identifying these compounds' molecular targets and binding modes. In particular, subsequent structure-based chemical optimization and target-based screening require a detailed understanding of the binding event. Here, we use directed evolution and whole-genome sequencing of a drug-sensitive S. cerevisiae strain to identify the yeast ortholog of TcCyp51, lanosterol-14-alpha-demethylase (TcCyp51), as the target of MMV001239, a benzamide compound with activity against Trypanosoma cruzi, the etiological agent of Chagas disease. We show that parasites treated with MMV0001239 phenocopy parasites treated with another TcCyp51 inhibitor, posaconazole, accumulating both lanosterol and eburicol. Direct drug-protein binding of MMV0001239 was confirmed through spectrophotometric binding assays and X-ray crystallography, revealing a binding site shared with other antitrypanosomal compounds that target Cyp51. These studies provide a new probe chemotype for TcCyp51 inhibition.


Asunto(s)
Inhibidores de 14 alfa Desmetilasa/uso terapéutico , Enfermedad de Chagas/tratamiento farmacológico , Evolución Molecular Dirigida , Tripanocidas/uso terapéutico , Inhibidores de 14 alfa Desmetilasa/química , Inhibidores de 14 alfa Desmetilasa/farmacología , Secuencia de Aminoácidos , Enfermedad de Chagas/parasitología , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Cromatografía de Gases y Espectrometría de Masas , Simulación del Acoplamiento Molecular , Plasmodium falciparum/efectos de los fármacos , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/genética , Espectrofotometría Ultravioleta , Esterol 14-Desmetilasa/efectos de los fármacos , Tripanocidas/química , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Trypanosoma cruzi/enzimología
7.
Phytochemistry ; 122: 113-118, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26632528

RESUMEN

Bioassay-guided fractionation of two marine cyanobacterial extracts using the H-460 human lung cancer cell line and the OVC-5 human ovarian cancer cell line led to the isolation of three related α-methoxy-ß, ß'-dimethyl-γ-pyrones each containing a modified alkyl chain, one of which was identified as the previously reported kalkipyrone and designated kalkipyrone A. The second compound was an analog designated kalkipyrone B. The third was identified as the recently reported yoshinone A, also isolated from a marine cyanobacterium. Kalkipyrone A and B were obtained from a field-collection of the cyanobacterium Leptolyngbya sp. from Fagasa Bay, American Samoa, while yoshinone A was isolated from a field-collection of cyanobacteria (cf. Schizothrix sp.) from Panama. One-dimensional and two-dimensional NMR experiments were used to determine the overall structures and relative configurations of the kalkipyrones, and the absolute configuration of kalkipyrone B was determined by (1)H NMR analysis of diastereomeric Mosher's esters. Kalkipyrone A showed good cytotoxicity to H-460 human lung cancer cells (EC50=0.9µM), while kalkipyrone B and yoshinone A were less active (EC50=9.0µM and >10µM, respectively). Both kalkipyrone A and B showed moderate toxicity to Saccharomyces cerevisiae ABC16-Monster strain (IC50=14.6 and 13.4µM, respectively), whereas yoshinone A was of low toxicity to this yeast strain (IC50=63.8µM).


Asunto(s)
Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Cianobacterias/química , Pironas/aislamiento & purificación , Pironas/farmacología , Antineoplásicos/química , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Biología Marina , Estructura Molecular , Panamá , Pironas/química
8.
Sci Rep ; 6: 27806, 2016 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-27291296

RESUMEN

The spiroindolones, a new class of antimalarial medicines discovered in a cellular screen, are rendered less active by mutations in a parasite P-type ATPase, PfATP4. We show here that S. cerevisiae also acquires mutations in a gene encoding a P-type ATPase (ScPMA1) after exposure to spiroindolones and that these mutations are sufficient for resistance. KAE609 resistance mutations in ScPMA1 do not confer resistance to unrelated antimicrobials, but do confer cross sensitivity to the alkyl-lysophospholipid edelfosine, which is known to displace ScPma1p from the plasma membrane. Using an in vitro cell-free assay, we demonstrate that KAE609 directly inhibits ScPma1p ATPase activity. KAE609 also increases cytoplasmic hydrogen ion concentrations in yeast cells. Computer docking into a ScPma1p homology model identifies a binding mode that supports genetic resistance determinants and in vitro experimental structure-activity relationships in both P. falciparum and S. cerevisiae. This model also suggests a shared binding site with the dihydroisoquinolones antimalarials. Our data support a model in which KAE609 exerts its antimalarial activity by directly interfering with P-type ATPase activity.


Asunto(s)
Antimaláricos/metabolismo , Indoles/metabolismo , ATPasas Tipo P/metabolismo , Compuestos de Espiro/metabolismo , Secuencia de Aminoácidos , Antimaláricos/química , Antimaláricos/farmacología , Sitios de Unión , Sistemas CRISPR-Cas/genética , Citosol/química , Citosol/efectos de los fármacos , Farmacorresistencia Fúngica , Indoles/química , Indoles/farmacología , Concentración 50 Inhibidora , Simulación del Acoplamiento Molecular , ATPasas Tipo P/antagonistas & inhibidores , ATPasas Tipo P/genética , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/enzimología , Estructura Terciaria de Proteína , ATPasas de Translocación de Protón/antagonistas & inhibidores , ATPasas de Translocación de Protón/genética , ATPasas de Translocación de Protón/metabolismo , Proteínas Protozoarias/antagonistas & inhibidores , Proteínas Protozoarias/metabolismo , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/enzimología , Proteínas de Saccharomyces cerevisiae/antagonistas & inhibidores , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN , Compuestos de Espiro/química , Compuestos de Espiro/farmacología , Relación Estructura-Actividad , Secuenciación Completa del Genoma
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