Publications by authors named "Arielle Butts"

New drugs and mechanisms of action targeting are urgently needed to solve the global pandemic of tuberculosis. We previously demonstrated that the 8-hydroxyquinoline series has rapid bactericidal activity against . In this work, we determined that the activity of the 8HQ series is potentiated by copper ions and that the activity is dependent on copper since activity was reduced when copper was depleted from the medium.

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Article Synopsis
  • - We synthesized a new arylsulfonamide that showed effectiveness against both extracellular and intracellular bacilli, while also displaying selectivity in its action against HepG2 cells.
  • - The drug disrupts bacterial cell wall synthesis, likely targeting the MmpL3 protein, which is known to export mycolic acids necessary for the bacterial cell wall.
  • - A specific mutation in the MmpL3 protein led to some resistance against the drug, further supporting the idea that MmpL3 is the main target of the compound's action.
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Background: One of the DSM-5 criteria for Alcohol Use Disorder is continued alcohol consumption despite negative consequences. This has been modeled in mice using adulteration of alcohol solution with the bitter tastant quinine. Mice that continue to consume alcohol despite this adulteration are considered aversion resistant.

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We previously identified a phenylthiourea series with activity against intracellular Mycobacterium tuberculosis using a high-throughput, high-content assay. We conducted a catalog structure-activity relationship study with a collection of 35 analogs. We identified several thiourea derivatives with excellent potency against intracellular bacteria and good selectivity over eukaryotic cells.

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Fungal fatty acid (FA) synthase and desaturase enzymes are essential for the growth and virulence of human fungal pathogens. These enzymes are structurally distinct from their mammalian counterparts, making them attractive targets for antifungal development. However, there has been little progress in identifying chemotypes that target fungal FA biosynthesis.

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A recent study demonstrated that the insertion of poly-adenosine (poly-A) tracts into an open reading frame can suppress expression of the encoded protein in both prokaryotic and eukaryotic species. Furthermore, the degree of suppression is proportional to the length of the poly-A insertion, which can therefore provide a reliable and predictable means to titrate a specific protein's expression. The goal of this study was to determine if this methodology can be applied to modulate the expression of proteins in the prevalent human fungal pathogen, Insertion of increasing numbers of AAA codons encoding lysine at the N terminus of the lanosterol demethylase (Erg11p) progressively diminished expression without significantly reducing the levels of mRNA.

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The increasing incidence of and high mortality rates associated with invasive fungal infections (IFIs) impose an enormous clinical, social, and economic burden on humankind. In addition to microbiological resistance to existing antifungal drugs, the large number of unexplained treatment failures is a serious concern. Due to the extremely limited therapeutic options available, it is critical to identify and understand the various causes of treatment failure if patient outcomes are to improve.

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Article Synopsis
  • Calcium is crucial for cell signaling in eukaryotes, but must be kept low in resting cells to prevent toxicity; in fungi, excess calcium is stored in vacuoles through pumps like Vcx1p and Pmc1p.
  • The study investigated the roles of these calcium pumps in a human fungal pathogen's ability to grow, form biofilms, and cause disease, finding that Pmc1p is essential for these processes.
  • Pmc1p also impacts the pathogen's resistance to antifungals, indicating that maintaining calcium balance is vital for fungal survival and virulence, and could lead to new treatment strategies.
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Increased expression of drug efflux pumps and changes in the target enzyme Erg11p are known to contribute to azole resistance in , one of the most prevalent fungal pathogens. Mutations that inactivate , which encodes sterol Δ-desaturase, also confer azole resistance. However, it is unclear whether the loss of Erg3p activity is sufficient to confer resistance within the mammalian host, and relatively few mutants have been reported among azole-resistant clinical isolates.

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The incidence of invasive fungal infections has risen significantly in recent decades as medical interventions have become increasingly aggressive. These infections are extremely difficult to treat due to the extremely limited repertoire of systemic antifungals, the development of drug resistance, and the extent to which the patient's immune function is compromised. Even when the appropriate antifungal therapies are administered in a timely fashion, treatment failure is common, even in the absence of microbial resistance.

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Traditional approaches to drug discovery are frustratingly inefficient and have several key limitations that severely constrain our capacity to rapidly identify and develop novel experimental therapeutics. To address this, we have devised a second-generation target-based whole-cell screening assay based on the principles of competitive fitness, which can rapidly identify target-specific and physiologically active compounds. Briefly, strains expressing high, intermediate, and low levels of a preselected target protein are constructed, tagged with spectrally distinct fluorescent proteins (FPs), and pooled.

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As the rates of systemic fungal infections continue to rise and antifungal drug resistance becomes more prevalent, there is an urgent need for new therapeutic options. This issue is exacerbated by the limited number of systemic antifungal drug classes. However, the discovery, development, and approval of novel antifungals is an extensive process that often takes decades.

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Cryptococcosis is one of the most important invasive fungal infections and is a significant contributor to the mortality associated with HIV/AIDS. As part of our program to repurpose molecules related to the selective estrogen receptor modulator (SERM) tamoxifen as anti-cryptococcal agents, we have explored the structure-activity relationships of a set of structurally diverse SERMs and tamoxifen derivatives. Our data provide the first insights into the structural requirements for the antifungal activity of this scaffold.

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The fungal meningitis pathogen Cryptococcus neoformans is a central driver of mortality in HIV/AIDS. We report a genome-scale chemical genetic data map for this pathogen that quantifies the impact of 439 small-molecule challenges on 1,448 gene knockouts. We identified chemical phenotypes for 83% of mutants screened and at least one genetic response for each compound.

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Unlabelled: Cryptococcosis is an infectious disease of global significance for which new therapies are needed. Repurposing previously developed drugs for new indications can expedite the translation of new therapies from bench to beside. Here, we characterized the anti-cryptococcal activity and antifungal mechanism of estrogen receptor antagonists related to the breast cancer drugs tamoxifen and toremifene.

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New, more accessible therapies for cryptococcosis represent an unmet clinical need of global importance. We took a repurposing approach to identify previously developed drugs with fungicidal activity toward Cryptococcus neoformans, using a high-throughput screening assay designed to detect drugs that directly kill fungi. From a set of 1,120 off-patent medications and bioactive molecules, we identified 31 drugs/molecules with fungicidal activity, including 15 drugs for which direct antifungal activity had not previously been reported.

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