An investigation into the effect of a phosphine coligand on the activation of precatalysts for manganese-catalyzed C-H bond functionalization is reported. Although simple precatalysts [MnBr(CO)] and [Mn(CO)] are used extensively in these reactions, there is a dearth of alternate precatalyst structures, which has hindered the development of structure-activity relationships. In this work, the effect of substituting a carbonyl ligand for a phosphine ligand is reported.
View Article and Find Full Text PDFSolid electrolytes (SEs) typically consist of a static framework of anions (FA) and a sublattice of mobile cations (M), with non-covalent dispersion interactions (E) playing a key role in structural stability. However, the impact of these interactions on M-ion migration-whether they assist or hinder it-remains unclear. In this study, we investigate the diffusion barriers of M-ions in SE frameworks, focusing on the MBH family (M = Li, Na, K), and clarify the role of non-covalent interactions.
View Article and Find Full Text PDFThe global healthcare and economic challenges caused by the pandemic of COVID-19 reinforced the urgent demand for quick and effective therapeutic and preventative interventions. While vaccines served as the frontline of defense, antivirals emerged as adjunctive countermeasures, especially for people who developed infection, were immunocompromised, or were reluctant to be vaccinated. Beyond the serious complications of SARS-CoV-2 infection, the threats of long-COVID and the potential for zoonotic spillover continue to be significant health concerns that cannot be overlooked.
View Article and Find Full Text PDFThe Ras GTPase-activating protein SH3-domain-binding protein 1 (G3BP1) serves as a formidable barrier to viral replication by generating stress granules (SGs) in response to viral infections. Interestingly, viruses, including SARS-CoV-2, have evolved defensive mechanisms to hijack SG proteins like G3BP1 for the dissipation of SGs that lead to the evasion of the host's immune responses. Previous research has demonstrated that the interaction between the NTF2-like domain of G3BP1 (G3BP1) and the intrinsically disordered N-terminal domain (NTD-N) of the N-protein plays a crucial role in regulating viral replication and pathogenicity.
View Article and Find Full Text PDFThe emergence of the SARS-CoV-2 Omicron variant highlights the need for innovative strategies to address evolving viral threats. This study bioengineered three nanobodies H11-H4, C5, and H3 originally targeting the Wuhan RBD, to bind more effectively to the Omicron RBD. A structure-based in silico affinity maturation pipeline was developed to enhance their binding affinities.
View Article and Find Full Text PDFDengue virus (DENV) envelope glycoprotein Domain III (EDIII) is critical for viral entry, highly immunogenic, and induces robust neutralizing antibody response. It is a prominent candidate for designing subunit-based vaccines and can also be harnessed as an antigenic bait for isolation of neutralizing human mAbs. Here, we describe an optimized method for high-yield expression of recombinant domain EDIII protein from DENV serotypes 1 to 4 in different Escherichia coli (E.
View Article and Find Full Text PDFPhthalate diesters are important pollutants and act as endocrine disruptors. While certain bacterial esterases have been identified for phthalate diesters degradation to monoesters, their structural and mechanistic characteristics remain largely unexplored. Here, we highlight the potential of the thermostable and pH-tolerant EstS1 esterase from Sulfobacillus acidophilus DSM10332 to degrade high molecular weight bis(2-ethylhexyl) phthalate (DEHP) by combining biophysical and biochemical approaches along with high-resolution EstS1 crystal structures of the apo form and with bound substrates, products, and their analogs to elucidate its mechanism.
View Article and Find Full Text PDFCurrent research efforts are underway to create novel approaches for the efficient diagnosis, monitoring, and mitigation of Kyasanur Forest Disease Virus (KFDV) infections. Flavivirus subunit-based vaccines based on envelope glycoprotein EDIII are now in preclinical and clinical research stages. Efficient purification and isolation methods for surface immunogenic viral antigens, including the recombinant envelope immunoglobulin-like domain III (rEDIII) protein, are crucial for the production and manufacturing of promising vaccine candidates that have been extensively assessed in previous literature.
View Article and Find Full Text PDFBiochem Biophys Res Commun
November 2024
ACS Appl Mater Interfaces
September 2024
Sodium-ion batteries are emerging as promising alternatives to conventional lithium-based technology, offering solutions to challenges in large-scale grid storage. However, the capacity of conventional graphite-based anodes for storing Na-ions is inherently limited by suboptimal thermodynamic interactions and irreversible structural changes that occur in the anode during charge-discharge cycles. Herein, we present a computational design that explores the potential of graphullerene, a two-dimensional framework with interconnected fullerene moieties, for the reversible storage of Na-ions.
View Article and Find Full Text PDFThe coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may be over, but its variants continue to emerge, and patients with mild symptoms having long COVID is still under investigation. SARS-CoV-2 infection leading to elevated cytokine levels and suppressed immune responses set off cytokine storm, fatal systemic inflammation, tissue damage, and multi-organ failure. Thus, drug molecules targeting the SARS-CoV-2 virus-specific proteins or capable of suppressing the host inflammatory responses to viral infection would provide an effective antiviral therapy against emerging variants of concern.
View Article and Find Full Text PDFThe nucleocapsid (N) protein of SARS-CoV-2 plays a pivotal role in encapsulating the viral genome. Developing antiviral treatments for SARS-CoV-2 is imperative due to the diminishing immunity of the available vaccines. This study targets the RNA-binding site located in the N-terminal domain (NTD) of the N-protein to identify the potential antiviral molecules against SARS-CoV-2.
View Article and Find Full Text PDFThe Togaviridae family comprises several New- and Old-World Alphaviruses that have been responsible for thousands of human illnesses, including the RNA arbovirus Chikungunya virus (CHIKV). Firstly, it was reported in Tanzania in 1952 but rapidly it spread to several countries from Europe, Asia, and the Americas. Since then, CHIKV has been circulating in diverse countries around the world, leading to increased morbidity rates.
View Article and Find Full Text PDFSite-predictable and chemoselective C-H bond functionalization reactions offer synthetically powerful strategies for the step-economic diversification of both feedstock and fine chemicals. Many transition-metal-catalyzed methods have emerged for the selective activation and functionalization of C-H bonds. However, challenges of regio- and chemoselectivity have emerged with application to highly complex molecules bearing significant functional group density and diversity.
View Article and Find Full Text PDFDeveloping more efficient catalytic processes using abundant and low toxicity transition metals is key to enable their mainstream use in synthetic chemistry. We have rationally designed a new Mn(i)-catalyst for hydroarylation reactions that displays much improved catalytic activity over the commonly used MnBr(CO). Our catalyst, MnBr(CO)(MeCN), avoids the formation of the off-cycle manganacycle-(CO) species responsible for low catalyst activity, allowing near room temperature hydroarylation of alkenes and alkynes with broad functional group tolerance including late stage functionalisation and diversification of bioactive molecules.
View Article and Find Full Text PDFAntimicrob Agents Chemother
March 2022
Alphaviruses cause animal or human diseases that are characterized by febrile illness, debilitating arthralgia, or encephalitis. Selective estrogen receptor modulators (SERMs), a class of FDA-approved drugs, have been shown to possess antiviral activities against multiple viruses, including hepatitis C virus, Ebola virus, dengue virus, and vesicular stomatitis virus. Here, we evaluated three SERM compounds, namely, 4-hydroxytamoxifen, tamoxifen, and clomifene, for plausible antiviral properties against two medically important alphaviruses, chikungunya virus (CHIKV) and Sindbis virus (SINV).
View Article and Find Full Text PDFCurr Microbiol
December 2021
The sudden rise in COVID-19 cases in 2020 and the incessant emergence of fast-spreading variants have created an alarming situation worldwide. Besides the continuous advancements in the design and development of vaccines to combat this deadly pandemic, new variants are frequently reported, possessing mutations that rapidly outcompeted an existing population of circulating variants. As concerns grow about the effects of mutations on the efficacy of vaccines, increased transmissibility, immune escape, and diagnostic failures are few other apprehensions liable for more deadly waves of COVID-19.
View Article and Find Full Text PDFBiochem Biophys Res Commun
November 2021
The native pumpkin 2S albumin, a multifunctional protein, possess a variety of potential biotechnologically exploitable properties. The present study reports the characterization of recombinant pumpkin 2S albumin (rP2SA) and unraveling of its potential DNA/RNA binding site. The purification and characterization of the rP2SA established that it retains the characteristic α-helical structure and exhibited comparable DNase, RNase, antifungal and anti-proliferative activities as native protein.
View Article and Find Full Text PDFBioorg Med Chem
September 2021
The ongoing COVID-19 pandemic, periodic recurrence of viral infections, and the emergence of challenging variants has created an urgent need of alternative therapeutic approaches to combat the spread of viral infections, failing to which may pose a greater risk to mankind in future. Resilience against antiviral drugs or fast evolutionary rate of viruses is stressing the scientific community to identify new therapeutic approaches for timely control of disease. Host metabolic pathways are exquisite reservoir of energy to viruses and contribute a diverse array of functions for successful replication and pathogenesis of virus.
View Article and Find Full Text PDFRe-emergence and global expansion of Chikungunya virus (CHIKV) from Africa to Indian Subcontinent in 2013, has significantly resulted in chronic morbidities in infected individuals. The burden of CHIKV on human population is still uncertain, owing to lack of vaccine and underdiagnosis. Due to the absence of vaccine or antiviral therapeutics, timely diagnosis and detection of CHIKV is vital for minimizing virus transmission.
View Article and Find Full Text PDFThe rapidly spreading, highly contagious and pathogenic SARS-coronavirus 2 (SARS-CoV-2) associated Coronavirus Disease 2019 (COVID-19) has been declared as a pandemic by the World Health Organization (WHO). The novel 2019 SARS-CoV-2 enters the host cell by binding of the viral surface spike glycoprotein (S-protein) to cellular angiotensin converting enzyme 2 (ACE2) receptor. The virus specific molecular interaction with the host cell represents a promising therapeutic target for identifying SARS-CoV-2 antiviral drugs.
View Article and Find Full Text PDFMater Sci Eng C Mater Biol Appl
July 2020
Due to the epidemic nature, Chikungunya virus (CHIKV), arthropod-borne alphaviruses, is considered as a potential public health threat worldwide. Currently, no antiviral drug or vaccine is available against alphaviruses. Nanotechnology with green synthesis of nanoparticles is a novel and emerging interdisciplinary field of science that involves the production and usage of nanomaterials.
View Article and Find Full Text PDFJ Indian Prosthodont Soc
October 2019
Aim: The complete denture fracture of denture may ruin the routine life of an edentulous patient. The aim of the present study was to propose and evaluate a new classification system for denture fractures.
Settings And Design: Cross sectional -Survey.
Int J Clin Pediatr Dent
June 2016
Traumatic injuries to primary dentition may interfere with the development of permanent dentition. Among the many malformations, dilaceration is particularly important to the clinician. Management of dilacerated maxillary central incisor requires a multidisciplinary approach.
View Article and Find Full Text PDFObjective: The aim of this study was to determine any relationship, if exists, between the patient's mental attitude with age, sex, or educational qualification.
Methods: A total of 200 patients who attended the outpatient department during a span of 1 year, for the fabrication of new complete dentures, were chosen for the study. After completing a routine case history and examination, a questionnaire was filled by the clinician as answered by the patient.