Discovery of PLD4 modulators by high-throughput screening and kinetic analysis.

Phospholipase D3 (PLD3) and D4 (PLD4) are endolysosomal exonucleases of ssDNA and ssRNA that regulate innate immunity. Polymorphisms of these enzymes are correlated with numerous human diseases, including Alzheimer's, rheumatoid arthritis, and systemic sclerosis. Pharmacological modulation of these immunoregulatory proteins may yield novel immunotherapies and adjuvants.

Transformation of a Metal Chelate into a "Catch and Anchor" Inhibitor of Botulinum A Protease.

Targeting the botulinum neurotoxin light chain (LC) metalloprotease using small-molecule metal chelate inhibitors is a promising approach to counter the effects of the lethal toxin. However, to overcome the pitfalls associated with simple reversible metal chelate inhibitors, it is crucial to investigate alternative scaffolds/strategies. In conjunction with Atomwise Inc.

Identification of Slow-Binding Inhibitors of the BoNT/A Protease.

Botulinum neurotoxin A (BoNT/A) is a lethal toxin, which causes botulism, and is categorized as a bioterrorism threat, which causes flaccid paralysis and death. Botulinum A neurotoxicity is governed through its light chain (LC), a zinc metalloprotease. Pharmacological investigations aimed at negating BoNT/A's LC have typically looked to inhibitors that have been shown to inhibit the light chain's activity by reversible zinc chelation within its active site.

From Fragment to Lead: De Novo Design and Development toward a Selective FGFR2 Inhibitor.

Fibroblast growth factor receptors (FGFRs) are implicated in a range of cancers with several pan-kinase and selective-FGFR inhibitors currently being evaluated in clinical trials. Pan-FGFR inhibitors often cause toxic side effects and few examples of subtype-selective inhibitors exist. Herein, we describe a structure-guided approach toward the development of a selective FGFR2 inhibitor.

Use of Crystallography and Molecular Modeling for the Inhibition of the Botulinum Neurotoxin A Protease.

Botulinum neurotoxins (BoNTs) are extremely toxic and have been deemed a Tier 1 potential bioterrorism agent. The most potent and persistent of the BoNTs is the "A" serotype, with strategies to counter its etiology focused on designing small-molecule inhibitors of its light chain (LC), a zinc-dependent metalloprotease. The successful structure-based drug design of inhibitors has been confounded as the LC is highly flexible with significant morphological changes occurring upon inhibitor binding.

Modulators of immunoregulatory exonucleases PLD3 and PLD4 identified by high-throughput screen.

PLD3 and PLD4 have recently been revealed to be endosomal exonucleases that regulate the innate immune response by digesting the ligands of nucleic acid sensors. These enzymes can suppress RNA and DNA innate immune sensors like toll-like receptor 9, and PLD4-deficent mice exhibit inflammatory disease. Targeting these immunoregulatory enzymes presents an opportunity to indirectly regulate innate immune nucleic acid sensors that could yield immunotherapies, adjuvants, and nucleic acid drug stabilizers.

Irreversible inhibition of BoNT/A protease: proximity-driven reactivity contingent upon a bifunctional approach.

Botulinum neurotoxin A (BoNT/A) is categorized as a Tier 1 bioterrorism agent and persists within muscle neurons for months, causing paralysis. A readily available treatment that abrogates BoNT/A's toxicity and longevity is a necessity in the event of a widespread BoNT/A attack and for clinical treatment of botulism, yet remains an unmet need. Herein, we describe a comprehensive warhead screening campaign of bifunctional hydroxamate-based inhibitors for the irreversible inhibition of the BoNT/A light chain (LC).

Synthetic fluorescent MYC probe: Inhibitor binding site elucidation and development of a high-throughput screening assay.

We report the discovery of a fluorescent small molecule probe. This probe exhibits an emission increase in the presence of the oncoprotein MYC that can be attenuated by a competing inhibitor. Hydrogen-deuterium exchange mass spectrometry analysis, rationalized by induced-fit docking, suggests it binds to the "coiled-coil" region of the leucine zipper domain.

COVALENT INHIBITION OF BOTULINUM NEUROTOXIN A - EXPLORATION OF WARHEAD REACTIVITY AND FUNCTION USING A BIFUNCTIONAL APPROACH.

Introduction And Objectives: Botulinum neurotoxin A (BoNT/A) is extremely toxic possessing an estimated intravenous LD of 1-2 ng/kg and as such has been designated a category A bioterrorism agent. BoNT/A also possesses an extremely long half-life and persists within muscle neurons for months to >1 year. Because of BoNT/A longevity, we have utilized covalent inhibition as a means to abrogate BoNT/A's toxicity.

Identification of 3-hydroxy-1,2-dimethylpyridine-4(1)-thione as a metal-binding motif for the inhibition of botulinum neurotoxin A.

Botulinum neurotoxin serotype A (BoNT/A) is an important therapeutic target owing to its extremely potent nature, but also has potential use as a biowarfare agent. Currently, no therapeutic exists to reverse the long-lasting paralysis caused by BoNT/A. Herein, we describe the identification of 3-hydroxy-1,2-dimethylpyridine-4(1)-thione (3,4-HOPTO) as a metal binding warhead for the inhibition of BoNT/A1.

Catch and Anchor Approach To Combat Both Toxicity and Longevity of Botulinum Toxin A.

Botulinum neurotoxins have remarkable persistence (∼weeks to months in cells), outlasting the small-molecule inhibitors designed to target them. To address this disconnect, inhibitors bearing two pharmacophores-a zinc binding group and a Cys-reactive warhead-were designed to leverage both affinity and reactivity. A series of first-generation bifunctional inhibitors was achieved through structure-based inhibitor design.

Identification of an Indazole-Based Pharmacophore for the Inhibition of FGFR Kinases Using Fragment-Led Design.

Structure-based drug design (SBDD) has become a powerful tool utilized by medicinal chemists to rationally guide the drug discovery process. Herein, we describe the use of SPROUT, a -based program, to identify an indazole-based pharmacophore for the inhibition of fibroblast growth factor receptor (FGFR) kinases, which are validated targets for cancer therapy. Hit identification using SPROUT yielded 6-phenylindole as a small fragment predicted to bind to FGFR1.