Being a component of the Ras/Raf/MEK/ERK signaling pathway crucial for cellular responses, the VRAF murine sarcoma viral oncogene homologue B1 (BRAF) kinase has emerged as a promising target for anticancer drug discovery due to oncogenic mutations that lead to pathway hyperactivation. Despite the discovery of several small-molecule BRAF kinase inhibitors targeting oncogenic mutants, their clinical utility has been limited by challenges such as off-target effects and suboptimal pharmacological properties. This study focuses on identifying miniprotein inhibitors for the oncogenic V600E mutant BRAF, leveraging their potential as versatile drug candidates.
View Article and Find Full Text PDFThe elevated activity of leucine-rich repeat kinase 2 (LRRK2) is implicated in the pathogenesis of Parkinson's disease (PD). The quest for effective LRRK2 inhibitors has been impeded by the formidable challenge of crossing the blood-brain barrier (BBB). We leveraged structure-based de novo design and developed robust three-dimensional quantitative structure-activity relationship (3D-QSAR) models to predict BBB permeability, enhancing the likelihood of the inhibitor's brain accessibility.
View Article and Find Full Text PDFMarine mussels adhere to virtually any surface via 3,4-dihydroxyphenyl-L-alanines (L-DOPA), an amino acid largely contained in their foot proteins. The biofriendly, water-repellent, and strong adhesion of L-DOPA are unparalleled by any synthetic adhesive. Inspired by this, we computationally designed diverse derivatives of DOPA and studied their potential as adhesives or coating materials.
View Article and Find Full Text PDFThe hERG potassium channel serves as an annexed target for drug discovery because the associated off-target inhibitory activity may cause serious cardiotoxicity. Quantitative structure-activity relationship (QSAR) models were developed to predict inhibitory activities against the hERG potassium channel, utilizing the three-dimensional (3D) distribution of quantum mechanical electrostatic potential (ESP) as the molecular descriptor. To prepare the optimal atomic coordinates of dataset molecules, pairwise 3D structural alignments were carried out in order for the quantum mechanical cross correlation between the template and other molecules to be maximized.
View Article and Find Full Text PDFMissense mutations of leucine-rich repeat kinase 2 (LRRK2), including the G2019S mutant, are responsible for the pathogenesis of Parkinson's disease. In this work, structure-based virtual screening of a large chemical library was carried out to identify a number of novel inhibitors of the G2019S mutant of LRRK2, the biochemical potencies of which ranged from the low micromolar to the submicromolar level. The discovery of these potent inhibitors was made possible due to the modification of the original protein-ligand binding energy function in order to include an accurate ligand dehydration energy term.
View Article and Find Full Text PDFBruton's tyrosine kinase (BTK) is responsible for the pathogenesis of various autoimmune diseases and chronic lymphocytic leukemia. However, the discovery of efficient medicines has seen limited success due to the constitutively active mutants that acquired the drug resistance. To disclose the dual inhibitors against the wild-type BTK and the problematic drug-resistant C481S mutant, a large chemical library was virtually screened with extensive molecular docking simulations using two target proteins.
View Article and Find Full Text PDFMitochondrial respiratory supercomplexes mediate redox electron transfer, generating a proton gradient for ATP synthesis. To provide structural information on the function of supercomplexes in physiologically relevant conditions, we conducted cryoelectron microscopy studies with supercomplexes in a lipid-preserving state. Here, we present cryoelectron microscopy structures of bovine respiratory supercomplex IIIIIV by using a lipid-preserving sample preparation.
View Article and Find Full Text PDFA successful passage of the blood-brain barrier (BBB) is an essential prerequisite for the drug molecules designed to act on the central nervous system. The logarithm of blood-brain partitioning (LogBB) has served as an effective index of molecular BBB permeability. Using the three-dimensional (3D) distribution of the molecular electrostatic potential (ESP) as the numerical descriptor, a quantitative structure-activity relationship (QSAR) model termed AlphaQ was derived to predict the molecular LogBB values.
View Article and Find Full Text PDFRespiratory syncytial virus (RSV) infections are associated with severe bronchiolitis or pneumonia. Although palivizumab is used to prevent RSV infections, the occurrence of palivizumab-resistant RSV strains is increasing, and these strains pose a threat to public health. Herein, we report an antibody with affinity to the S275F RSV antigen, enabling the specific detection of palivizumab-resistant RSV strains.
View Article and Find Full Text PDFBackground: the proviral insertion site of Moloney murine leukemia (PIM) 1 kinase has served as a therapeutic target for various human cancers due to the enhancement of cell proliferation and the inhibition of apoptosis.
Methods: to identify effective PIM1 kinase inhibitors, structure-based virtual screening of natural products of plant origin and de novo design were carried out using the protein-ligand binding free energy function improved by introducing an adequate dehydration energy term.
Results: as a consequence of subsequent enzyme inhibition assays, four classes of PIM1 kinase inhibitors were discovered, with the biochemical potency ranging from low-micromolar to sub-micromolar levels.
Although the inhibitors of singly mutated epidermal growth factor receptor (EGFR) kinase are effective for the treatment of non-small cell lung cancer (NSCLC), their clinical efficacy has been limited due to the emergence of various double and triple EGFR mutants with drug resistance. It has thus become urgent to identify potent and selective inhibitors of triple mutant EGFRs resistant to first-, second-, and third-generation EGFR inhibitors. Herein, we report the discovery of potent and highly selective inhibitors of EGFR exon 19 p.
View Article and Find Full Text PDFDiscovery of an anticancer medicine using a single target protein has often been unsuccessful due to the complexity of pathogenic mechanisms as well as the presence of redundant signaling pathways. In this work, we attempted to find promising anticancer drug candidates by simultaneously targeting casein kinase 1 delta (CK1δ) and muscarinic acetylcholine receptor M3 (M3R). Through the structure-based virtual screening and de novo design with the modified potential function for protein-ligand binding, a series of benzo[4,5]imidazo[1,2-a][1,3,5]triazine-2-amine (BITA) derivatives were identified as CK1δ inhibitors and also as M3R antagonists.
View Article and Find Full Text PDFThe emergence and spread of antiviral drug-resistant viruses have been a worldwide challenge and a great concern for patient care. We report A4 antibody specifically recognizing and binding to the mutant I223R/H275Y neuraminidase and prove the applicability of A4 antibody for direct detection of antiviral multidrug-resistant viruses in various sensing platforms, including naked-eye detection, surface-enhanced Raman scattering-based immunoassay, and lateral flow system. The development of the A4 antibody enables fast, simple, and reliable point-of-care assays of antiviral multidrug-resistant influenza viruses.
View Article and Find Full Text PDFFactor inhibiting hypoxia-inducible factor (FIH) is a 2-oxoglutarate-dependent protein hydroxylase that catalyses C3 hydroxylations of protein residues. We report FIH can accept (D)- and (L)-residues for hydroxylation. The substrate selectivity of FIH differs for (D) and (L) epimers, e.
View Article and Find Full Text PDFHerein, graphite is proposed as a reliable Ca-intercalation anode in tetraglyme (G). When charged (reduced), graphite accommodates solvated Ca-ions (Ca-G) and delivers a reversible capacity of 62 mAh g that signifies the formation of a ternary intercalation compound, Ca-G·C. Mass/volume changes during Ca-G intercalation and the evolution of in operando X-ray diffraction studies both suggest that Ca-G intercalation results in the formation of an intermediate phase between stage-III and stage-II with a gallery height of 11.
View Article and Find Full Text PDFBioorg Med Chem Lett
July 2019
Structure based virtual screening attempts to discover DUSP1 inhibitors have yielded a scaffold featuring benzoxazole and acylthiourea pharmacophore. A series of its analogues were synthesized to explore structure activity relationship (SAR) of DUSP1 inhibition.
View Article and Find Full Text PDFWe establish a comprehensive quantitative structure-activity relationship (QSAR) model termed AlphaQ through the machine learning algorithm to associate the fully quantum mechanical molecular descriptors with various biochemical and pharmacological properties. Preliminarily, a novel method for molecular structural alignments was developed in such a way to maximize the quantum mechanical cross correlations among the molecules. Besides the improvement of structural alignments, three-dimensional (3D) distribution of the molecular electrostatic potential was introduced as the unique numerical descriptor for individual molecules.
View Article and Find Full Text PDFWe recently reported that AMP-activated protein kinase (AMPK) contributes to zinc-induced neuronal death by inducing Bim, a pro-apoptotic Bcl-2 homology domain 3-only protein, in a liver kinase B1 (LKB1)-dependent manner. Current data suggest AMPK plays key roles in excitotoxicity and ischemic brain injury, with zinc neurotoxicity representing at least one mechanism of ischemic neuronal death. Inhibition of AMPK could be a viable therapeutic strategy to prevent ischemic brain injury following stroke.
View Article and Find Full Text PDFCytosolic protein tyrosine phosphatase epsilon (cyt-PTPε) plays a central role in controlling differentiation and function of osteoclasts, whose overactivation causes osteoporosis. Based on our previous study reporting a number of cyt-PTPε inhibitory chemical compounds, we carried out a further and extended analysis of our compounds to examine their effects on cyt-PTPε-mediated dephosphorylation and on osteoclast organization and differentiation. Among five compounds showing target selectivity to cyt-PTPε over three other phosphatases in vitro, two compounds exhibited an inhibitory effect against the dephosphorylation of cellular Src protein, the cyt-PTPε substrate.
View Article and Find Full Text PDFWe have developed a novel oseltamivir derivative (oseltamivir hexylthiol; OHT) that exhibits a higher binding affinity for Tamiflu-resistant virus (Tamiflu resistance) than for the wild-type virus (Tamiflu-susceptible virus; WT) as an antibody. First, OHT-modified gold nanoparticles (OHT-GNPs) are used in a simple colorimetric assay as nanoprobes for the Tamiflu-resistant virus. In the presence of Tamiflu-resistant virus, they show a colorimetric change from deep red to purple because of the OHT-GNP aggregation driven by strong interactions between OHT and neuraminidase (NA) on the surface of the Tamiflu-resistance.
View Article and Find Full Text PDFAurora kinase A (AKA) has served as an effective molecular target for the development of cancer therapeutics. A series of potent AKA inhibitors with the (4-methoxy-pyrimidin-2-yl)-phenyl-amine (MPPA) scaffold are identified using a systematic computer-aided drug design protocol involving structure-based virtual screening, de novo design, and free energy perturbation (FEP) simulations. To enhance the accuracy of the virtual screening to find a proper molecular core and de novo design to optimize biochemical potency, we preliminarily improved the scoring function by implementing a reliable hydration energy term.
View Article and Find Full Text PDFDespite a wealth of persuasive evidence for the involvement of human small C-terminal domain phosphatase 1 (Scp1) in the impairment of neuronal differentiation and in Huntington's disease, small-molecule inhibitors of Scp1 have been rarely reported so far. This study aims to the discovery of both competitive and allosteric Scp1 inhibitors through the two-track virtual screening procedure. By virtue of the improvement of the scoring function by implementing a new molecular solvation energy term and by reoptimizing the atomic charges for the active-site Mg ion cluster, we have been able to identify three allosteric and five competitive Scp1 inhibitors with low-micromolar inhibitory activity.
View Article and Find Full Text PDFNext-generation epidermal growth factor receptor (EGFR) inhibitors against the d746-750/T790M/C797S mutation were discovered through two-track virtual screening and de novo design. A number of nanomolar inhibitors were identified using 2-aryl-4-aminoquinazoline as the molecular core and the modified binding energy function involving a proper dehydration term, which provides important structural insight into the key principles for high inhibitory activities against the d746-750/T790M/C797S mutant. Furthermore, some of these EGFR inhibitors showed a greater than 1000-fold selectivity for the d746-750/T790M/C797S mutant over the wild type, as well as nanomolar activity against the mutant.
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