Publications by authors named "Kumar Singh Saikatendu"

Article Synopsis
  • - The COVID Moonshot was a collaborative, open-science effort focused on finding a new drug to inhibit the SARS-CoV-2 main protease, which is crucial for the virus's survival.
  • - Researchers developed a novel noncovalent, nonpeptidic inhibitor that stands out from existing drugs targeting the same protease, employing advanced techniques like machine learning and high-throughput structural biology.
  • - Over 18,000 compound designs, 490 ligand-bound x-ray structures, and extensive assay data were generated and shared openly, creating a comprehensive and accessible knowledge base for future drug discovery efforts against coronaviruses.
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Target 2035, an international federation of biomedical scientists from the public and private sectors, is leveraging 'open' principles to develop a pharmacological tool for every human protein. These tools are important reagents for scientists studying human health and disease and will facilitate the development of new medicines. It is therefore not surprising that pharmaceutical companies are joining Target 2035, contributing both knowledge and reagents to study novel proteins.

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During the coronavirus disease 2019 (COVID-19) pandemic, a wave of rapid and collaborative drug discovery efforts took place in academia and industry, culminating in several therapeutics being discovered, approved and deployed in a 2-year time frame. This article summarizes the collective experience of several pharmaceutical companies and academic collaborations that were active in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antiviral discovery. We outline our opinions and experiences on key stages in the small-molecule drug discovery process: target selection, medicinal chemistry, antiviral assays, animal efficacy and attempts to pre-empt resistance.

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One aspirational goal of computational chemistry is to predict potent and drug-like binders for any protein, such that only those that bind are synthesized. In this Roadmap, we describe the launch of Critical Assessment of Computational Hit-finding Experiments (CACHE), a public benchmarking project to compare and improve small molecule hit-finding algorithms through cycles of prediction and experimental testing. Participants will predict small molecule binders for new and biologically relevant protein targets representing different prediction scenarios.

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Article Synopsis
  • The human proteome remains poorly understood twenty years after the initial human genome draft, with roughly 35% of proteins uncharacterized and under 5% targeted for drug discovery.
  • Despite advancements in genomics, translating this knowledge into effective medicines is challenging since proteins, not genes, govern biological functions.
  • The Target 2035 initiative unites biomedical scientists to develop new technologies aimed at creating comprehensive resources for studying the entire human proteome by the year 2035.
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The NIH Virtual SARS-CoV-2 Antiviral Summit, held on 6 November 2020, was organized to provide an overview on the status and challenges in developing antiviral therapeutics for coronavirus disease 2019 (COVID-19), including combinations of antivirals. Scientific experts from the public and private sectors convened virtually during a live videocast to discuss severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) targets for drug discovery as well as the preclinical tools needed to develop and evaluate effective small-molecule antivirals. The goals of the Summit were to review the current state of the science, identify unmet research needs, share insights and lessons learned from treating other infectious diseases, identify opportunities for public-private partnerships, and assist the research community in designing and developing antiviral therapeutics.

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Fragment screening is frequently used for hit identification. However, there was no report starting from a small fragment for the development of an anaplastic lymphoma kinase (ALK) inhibitor, despite the number of ALK inhibitors reported. We began our research with the fragment hit and our subsequent linker design, and its docking analysis yielded novel -1,2,2-trisubstituted cyclopropane .

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Protein arginine methyltransferase (PRMT) 4 (also known as coactivator-associated arginine methyltransferase 1; CARM1) is involved in a variety of biological processes and is considered as a candidate oncogene owing to its overexpression in several types of cancer. Selective PRMT4 inhibitors are useful tools for clarifying the molecular events regulated by PRMT4 and for validating PRMT4 as a therapeutic target. Here, we report the discovery of TP-064, a potent, selective, and cell-active chemical probe of human PRMT4 and its co-crystal structure with PRMT4.

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Potent, selective and broadly characterized small molecule modulators of protein function (chemical probes) are powerful research reagents. The pharmaceutical industry has generated many high-quality chemical probes and several of these have been made available to academia. However, probe-associated data and control compounds, such as inactive structurally related molecules and their associated data, are generally not accessible.

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Poly(ADP-ribose) polymerases (PARPs) use nicotinamide adenine dinucleotide (NAD) as a co-substrate to transfer ADP-ribose when it releases nicotinamide as the metabolized product. Enzymes of the PARP family play key roles in detecting and repairing DNA, modifying chromatin, regulating transcription, controlling energy metabolism, and inducing cell death. PARP14, the original member of the PARP family, has been reported to be associated with the development of inflammatory diseases and various cancer types, making it a potential therapeutic target.

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The transcription factor Nanog is an upstream regulator in early mammalian development and a key determinant of pluripotency in embryonic stem cells. Nanog binds to promoter elements of hundreds of target genes and regulates their expression by an as yet unknown mechanism. Here, we report the crystal structure of the murine Nanog homeodomain (HD) and analysis of its interaction with a DNA element derived from the Tcf3 promoter.

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Mature nonstructural protein-15 (nsp15) from the severe acute respiratory syndrome coronavirus (SARS-CoV) contains a novel uridylate-specific Mn2+-dependent endoribonuclease (NendoU). Structure studies of the full-length form of the obligate hexameric enzyme from two CoVs, SARS-CoV and murine hepatitis virus, and its monomeric homologue, XendoU from Xenopus laevis, combined with mutagenesis studies have implicated several residues in enzymatic activity and the N-terminal domain as the major determinant of hexamerization. However, the tight link between hexamerization and enzyme activity in NendoUs has remained an enigma.

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Conserved among all coronaviruses are four structural proteins: the matrix (M), small envelope (E), and spike (S) proteins that are embedded in the viral membrane and the nucleocapsid phosphoprotein (N), which exists in a ribonucleoprotein complex in the lumen. The N-terminal domain of coronaviral N proteins (N-NTD) provides a scaffold for RNA binding, while the C-terminal domain (N-CTD) mainly acts as oligomerization modules during assembly. The C terminus of the N protein anchors it to the viral membrane by associating with M protein.

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Background: The protein encoded by the SA1388 gene from Staphylococcus aureus was chosen for structure determination to elucidate its domain organization and confirm our earlier remote homology based prediction that it housed a nitrogen regulatory PII protein-like domain. SA1388 was predicted to contain a central PII-like domain and two flanking regions, which together belong to the NIF3-like protein family. Proteins like SA1388 remain a poorly studied group and their structural characterization could guide future investigations aimed at understanding their function.

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The severe acute respiratory syndrome coronavirus (SARS-CoV) possesses a large 29.7-kb positive-stranded RNA genome. The first open reading frame encodes replicase polyproteins 1a and 1ab, which are cleaved to generate 16 "nonstructural" proteins, nsp1 to nsp16, involved in viral replication and/or RNA processing.

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Replication of severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) requires proteolytic processing of the replicase polyprotein by two viral cysteine proteases, a chymotrypsin-like protease (3CLpro) and a papain-like protease (PLpro). These proteases are important targets for development of antiviral drugs that would inhibit viral replication and reduce mortality associated with outbreaks of SARS-CoV. In this work, we describe the 1.

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The crystal structure of a conserved domain of nonstructural protein 3 (nsP3) from severe acute respiratory syndrome coronavirus (SARS-CoV) has been solved by single-wavelength anomalous dispersion to 1.4 A resolution. The structure of this "X" domain, seen in many single-stranded RNA viruses, reveals a three-layered alpha/beta/alpha core with a macro-H2A-like fold.

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