DNA-encoded small molecule library technology has recently emerged as a new paradigm for identifying ligands against drug targets. To date, it has been used to identify ligands against targets that are soluble or overexpressed on cell surfaces. Here, we report applying cell-based selection methods to profile surfaces of mouse C2C12 myoblasts and myotube cells in an unbiased, target agnostic manner.
View Article and Find Full Text PDFDNA-encoded library (DEL) technology is a powerful platform for hit identification in academia and the pharmaceutical industry. When conducting off-DNA resynthesis hit confirmation after affinity selection, PCR/sequencing, and data analysis, one typically assumes a "one-to-one" relationship between the DNA tag and the chemical structure of the attached small-molecule it encodes. Because library synthesis often yields a mixture, this approximation increases the risk of overlooking positive discoveries and valuable information.
View Article and Find Full Text PDFDNA-encoded library technology (ELT) is a cutting-edge enabling technology platform for drug discovery. Here we describe how to design and synthesize a macrocyclic DNA-encoded library; how to perform selection, sequencing, and data analysis to identify potential active peptides; and how to synthesize off-DNA peptides to confirm activity. This approach provides an effective tool for pharmaceutical research based on peptides.
View Article and Find Full Text PDFDNA-encoded libraries (DELs) have been broadly applied to identify chemical probes for target validation and lead discovery. To date, the main application of the DEL platform has been the identification of reversible ligands using multiple rounds of affinity selection. Irreversible (covalent) inhibition offers a unique mechanism of action for drug discovery research.
View Article and Find Full Text PDFThe identification and prioritization of chemically tractable therapeutic targets is a significant challenge in the discovery of new medicines. We have developed a novel method that rapidly screens multiple proteins in parallel using DNA-encoded library technology (ELT). Initial efforts were focused on the efficient discovery of antibacterial leads against 119 targets from Acinetobacter baumannii and Staphylococcus aureus.
View Article and Find Full Text PDFIn the search of PI3K p110α wild type and H1047R mutant selective small molecule leads, an encoded library technology (ELT) campaign against the desired target proteins was performed which led to the discovery of a selective chemotype for PI3K isoforms from a three-cycle DNA encoded library. An X-ray crystal structure of a representative inhibitor from this chemotype demonstrated a unique binding mode in the p110α protein.
View Article and Find Full Text PDFTo identify novel antivirals to the hepatitis C virus (HCV) NS4B protein, we utilized encoded library technology (ELT), which enables purified proteins not amenable to standard biochemical screening methods to be tested against large combinatorial libraries in a short period of time. We tested NS4B against several DNA-encoded combinatorial libraries (DEL) and identified a single DEL feature that was subsequently progressed to off-DNA synthesis. The most active of the initial synthesized compounds had 50% inhibitory concentrations (IC50s) of 50 to 130 nM in a NS4B radioligand binding assay and 300 to 500 nM in an HCV replicon assay.
View Article and Find Full Text PDFPAD4 has been strongly implicated in the pathogenesis of autoimmune, cardiovascular and oncological diseases through clinical genetics and gene disruption in mice. New selective PAD4 inhibitors binding a calcium-deficient form of the PAD4 enzyme have validated the critical enzymatic role of human and mouse PAD4 in both histone citrullination and neutrophil extracellular trap formation for, to our knowledge, the first time. The therapeutic potential of PAD4 inhibitors can now be explored.
View Article and Find Full Text PDFThe inhibition of protein-protein interactions remains a challenge for traditional small molecule drug discovery. Here we describe the use of DNA-encoded library technology for the discovery of small molecules that are potent inhibitors of the interaction between lymphocyte function-associated antigen 1 and its ligand intercellular adhesion molecule 1. A DNA-encoded library with a potential complexity of 4.
View Article and Find Full Text PDFThe sirtuins SIRT1, SIRT2, and SIRT3 are NAD(+) dependent deacetylases that are considered potential targets for metabolic, inflammatory, oncologic, and neurodegenerative disorders. Encoded library technology (ELT) was used to affinity screen a 1.2 million heterocycle enriched library of DNA encoded small molecules, which identified pan-inhibitors of SIRT1/2/3 with nanomolar potency (e.
View Article and Find Full Text PDFThe metalloprotease ADAMTS-5 is considered a potential target for the treatment of osteoarthritis. To identify selective inhibitors of ADAMTS-5, we employed encoded library technology (ELT), which enables affinity selection of small molecule binders from complex mixtures by DNA tagging. Selection of ADAMTS-5 against a four-billion member ELT library led to a novel inhibitor scaffold not containing a classical zinc-binding functionality.
View Article and Find Full Text PDFInhibition of methionine aminopeptidase-2 (MetAP2) represents a novel approach to antiangiogenic therapy. We describe the synthesis and activity of fumagillin analogues that address the pharmacokinetic and safety liabilities of earlier candidates in this compound class. Two-step elaboration of fumagillol with amines yielded a diverse series of carbamates at C6 of the cyclohexane spiroepoxide.
View Article and Find Full Text PDFBiochemical combinatorial techniques such as phage display, RNA display and oligonucleotide aptamers have proven to be reliable methods for generation of ligands to protein targets. Adapting these techniques to small synthetic molecules has been a long-sought goal. We report the synthesis and interrogation of an 800-million-member DNA-encoded library in which small molecules are covalently attached to an encoding oligonucleotide.
View Article and Find Full Text PDFBACE-1 (beta-site amyloid precursor protein cleaving enzyme), a prominent target in Alzheimer's disease drug discovery efforts, was surveyed using Tethering technology to discover small molecule fragment ligands that bind to the enzyme active site. Screens of a library of >15000 thiol-containing fragments versus a panel of BACE-1 active site cysteine mutants under redox-controlled conditions revealed several novel amine-containing fragments that could be selectively captured by subsets of the tethering sites. For one such hit class, defined by a central aminobenzylpiperidine (ABP) moiety, X-ray crystal structures of BACE mutant-disulfide conjugates revealed that the fragment bound by engaging both catalytic aspartates with hydrogen bonds.
View Article and Find Full Text PDFHIV-1 TAR RNA functions critically in viral replication by binding the transactivating regulatory protein Tat. We recently identified several compounds that experimentally inhibit the Tat-TAR interaction completely at a 100 nM concentration. We used computational screening of the 181,000-compound Available Chemicals Directory against the three-dimensional structure of TAR [1].
View Article and Find Full Text PDFThere has been little prior effort to discover new drugs on the basis of a unique RNA structure. Binding of the viral transactivator Tat to the 5' bulge of the transactivation response (TAR) element is necessary for HIV-1 replication, so TAR RNA is a superb target. A computational approach was developed to screen a large chemical library for binding to a three-dimensional RNA structure.
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