Publications by authors named "Leah Cowen"

is the most common cause of life-threatening fungal infection in the developed world but remains a therapeutic challenge. Protein kinases have been rewarding drug targets across diverse indications but remain untapped for antifungal development. Previously, screening kinase inhibitors against revealed a 2,3-aryl-pyrazolopyridine, GW461484A (GW), which targets casein kinase 1 (CK1) family member Yck2.

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is a growing health concern as the leading causal agent of systemic candidiasis, a life-threatening fungal infection with a mortality rate of ~40% despite best available therapy. Yck2, a fungal casein kinase 1 (CK1) family member, is the cellular target of inhibitors YK-I-02 (YK) and MN-I-157 (MN). Here, multiplexed inhibitor beads paired with mass spectrometry (MIB/MS) employing ATP-competitive kinase inhibitors were used to define the selectivity of these Yck2 inhibitors across the global proteome.

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Fungal infections cause millions of deaths annually and are challenging to treat due to limited antifungal options and increasing drug resistance. Cryptococci are intrinsically resistant to the latest generation of antifungals, echinocandins, while , a notorious global threat, is also increasingly resistant. We performed a natural product extract screen for rescue of the activity of the echinocandin caspofungin against H99, identifying butyrolactol A, which restores echinocandin efficacy against resistant fungal pathogens, including .

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The eukaryotic serine/threonine protein phosphatase PP2A is a heterotrimeric enzyme composed of a scaffold A subunit, a regulatory B subunit, and a catalytic C subunit. Of the four known B subunits, the B"' subunit (known as striatin) interacts with the multi-protein striatin-interacting phosphatase and kinase (STRIPAK) complex. Orthologs of STRIPAK components were identified in Cryptococcus neoformans, namely PP2AA/Tpd3, PP2AC/Pph22, PP2AB/Far8, STRIP/Far11, SLMAP/Far9, and Mob3.

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Article Synopsis
  • - Fungal diseases impact over a billion individuals globally, presenting a significant health challenge.
  • - Naamidine A demonstrates the ability to inhibit various fungal pathogens, but its antifungal effect is compromised when excess zinc is added to the growth medium.
  • - The compound shows effectiveness against terbinafine-resistant fungi and has been proven effective in treating dermatomycosis in mice, indicating its potential for topical use in therapy.
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The eukaryotic serine/threonine protein phosphatase PP2A is a heterotrimeric enzyme composed of a scaffold A subunit, a regulatory B subunit, and a catalytic C subunit. Of the four known B subunits, the B"' subunit (known as striatin) interacts with the multi-protein striatin-interacting phosphatase and kinase (STRIPAK) complex. Orthologs of STRIPAK components were identified in , namely PP2AA/Tpd3, PP2AC/Pph22, PP2AB/Far8, STRIP/Far11, SLMAP/Far9, and Mob3.

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Article Synopsis
  • Fungal pathogens like Candida albicans are a major health concern with few treatment options, prompting researchers to identify key genes involved in their growth within the human body.
  • A pooled functional genomic screening method led to the discovery of an essential gene, C1_09670C (Rfa3), that has no counterpart in Saccharomyces cerevisiae, shedding light on novel therapeutic targets.
  • Additionally, the study identified another important gene, C3_06880W (Iml3), which functions in the cell cycle and is crucial for C. albicans fitness at high temperatures, linking it to the pathogen's virulence in living organisms.
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Translation inhibitors have therapeutic potential against Candida species. Here, we present a protocol to measure translation inhibition in Candida spp. We describe steps for employing an alkynylated methionine analog, L-homopropargylglycine (HPG), that becomes incorporated into newly synthesized proteins.

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At human body temperature, the fungal pathogen can transition from yeast to filamentous morphologies in response to host-relevant cues. Additionally, elevated temperatures encountered during febrile episodes can independently induce filamentation. However, the underlying genetic pathways governing this developmental transition in response to elevated temperatures remain largely unexplored.

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Article Synopsis
  • Plant-parasitic nematodes pose a significant threat to global crops, and the current move away from broad-spectrum nematicides limits farmers' control options.
  • Researchers have discovered a new compound, Cyprocide, which selectively targets and kills various types of nematodes while sparing other organisms.
  • Cyprocide is activated by specific nematode enzymes, highlighting its potential as a specialized solution to protect the food supply from nematode infestations.
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Candida albicans is a major fungal pathogen of humans that can cause serious systemic infections in vulnerable immunocompromised populations. One of its virulence attributes is its capacity to transition between yeast and filamentous morphologies, but our understanding of this process remains incomplete. Here, we analyzed data from a functional genomic screen performed with the C.

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Pathogenic fungi are an increasing public health concern. The emergence of antifungal resistance coupled with the scarce antifungal arsenal highlights the need for novel therapeutics. Fortunately, the past few years have witnessed breakthroughs in antifungal development.

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Candida species are among the most prevalent causes of systemic fungal infections, which account for ∼1.5 million annual fatalities. Here, we build on a compound screen that identified the molecule N-pyrimidinyl-β-thiophenylacrylamide (NP-BTA), which strongly inhibits Candida albicans growth.

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, one of the most prevalent human fungal pathogens, causes diverse diseases extending from superficial infections to deadly systemic mycoses. Currently, only three major classes of antifungal drugs are available to treat systemic infections: azoles, polyenes, and echinocandins. Alarmingly, the efficacy of these antifungals against is hindered both by basal tolerance toward the drugs and the development of resistance mechanisms such as alterations of the drug's target, modulation of stress responses, and overexpression of efflux pumps.

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Over recent decades, the global burden of fungal disease has expanded dramatically. It is estimated that fungal disease kills approximately 1.5 million individuals annually; however, the true worldwide burden of fungal infection is thought to be higher due to existing gaps in diagnostics and clinical understanding of mycotic disease.

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is a leading human fungal pathogen that often causes life-threatening infections in immunocompromised individuals. The ability of to transition between yeast and filamentous forms is key to its virulence, and this occurs in response to many host-relevant cues, including engulfment by host macrophages. While previous efforts identified genes required for filamentation in other conditions, the genes important for this morphological transition upon internalization by macrophages remained largely enigmatic.

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is an opportunistic human fungal pathogen that frequently causes life-threatening infections in immunocompromised individuals. To cause disease, the fungus employs several virulence traits, including its ability to transition between yeast and filamentous states. Previous work identified a role for the kinase Yak1 in regulating filamentation.

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Among fungal pathogens, infections by drug-resistant species continue to pose a major challenge to healthcare. This study aimed to evaluate the activity of the bioactive natural product, penta--galloyl-β-d-glucose (PGG) against multidrug-resistant (MDR) , MDR , and other MDR non- species. Here, we show that PGG has a minimum inhibitory concentration (MIC) of 0.

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Metabolic flexibility enables fungi to invade challenging host environments. In Candida albicans, a common cause of life-threatening infections in humans, an important contributor to flexibility is alternative oxidase (Aox) activity. Dramatic induction of this activity occurs under respiratory-stress conditions, which impair the classical electron transport chain (ETC).

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Hsp90 is a conserved molecular chaperone that facilitates the folding and function of hundreds of client proteins, many of which serve as core hubs of signal transduction networks. Hsp90 has a critical role in virulence of the opportunistic fungal pathogen Candida albicans, which exists as a natural commensal of the human microbiota and is a leading cause of invasive fungal infections, particularly in immunocompromised individuals. The ability of C.

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Rising drug resistance among pathogenic fungi, paired with a limited antifungal arsenal, poses an increasing threat to human health. To identify antifungal compounds, we screened the RIKEN natural product depository against representative isolates of four major human fungal pathogens. This screen identified NPD6433, a triazenyl indole with broad-spectrum activity against all screening strains, as well as the filamentous mold Aspergillus fumigatus.

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Q203 (telacebec) is an imidazopyridine amide (IPA) targeting the respiratory CIIICIV supercomplex of the mycobacterial electron transport chain (ETC). Aiming for a better understanding of the molecular mechanism of action of IPA, 27 analogues were prepared through a seven-step synthetic scheme. Oxygen consumption assay was designed to test the inhibition of purified CIIICIV by these compounds.

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Parasitic nematodes are a major threat to global food security, particularly as the world amasses 10 billion people amid limited arable land. Most traditional nematicides have been banned owing to poor nematode selectivity, leaving farmers with inadequate means of pest control. Here we use the model nematode Caenorhabditis elegans to identify a family of selective imidazothiazole nematicides, called selectivins, that undergo cytochrome-p450-mediated bioactivation in nematodes.

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