Human respiratory viruses represent a major global health burden, causing millions of severe infections and deaths annually. Despite the central role of vaccines in prevention, their limitations, such as incomplete coverage, waning immunity, and vulnerability to viral evolution, underscore the urgent need for effective antiviral therapeutics. This review examines the principles and applications of target-based antiviral drug development against human respiratory viruses, emphasizing the identification and exploitation of conserved viral and host targets. Key viral proteins, including RNA-dependent RNA polymerases, proteases, and fusion glycoproteins, are analyzed across major virus families such as coronaviruses, paramyxoviruses, and adenoviruses, highlighting their structural features, functional constraints, and therapeutic potential. We further explore the integration of high-throughput screening and rational drug design, supported by advances in structural biology, cryo-electron microscopy, and computational approaches, including artificial intelligence-driven drug discovery. These methodologies collectively enhance the precision and efficiency of antiviral development. However, significant challenges remain, particularly the conflict between viral mutation and target conservation, the rapid emergence of drug resistance, and the safety limitations of host-targeted therapies. Finally, we discuss emerging strategies to overcome these barriers, including combination therapies and the development of broad-spectrum antivirals targeting conserved molecular mechanisms. This paper highlights a framework for the rational design of durable antiviral interventions capable of addressing both existing and emerging respiratory viral threats.
S. Samrat, Gauri Srivastava, Ran Zhang et al.· Pathogens· 0 citations
The global rise of drug-resistant Mycobacterium tuberculosis (Mtb) underscores an urgent need for antitubercular agents with novel targets and mechanisms of action. Among these, the de novo purine biosynthesis pathway is essential for Mtb growth and survival, making its constituent enzymes attractive targets for therapeutic intervention. Within this pathway, adenylosuccinate (ADS) synthetase (ADSS) Rv0357c catalyzes the first committed step in biosynthesis of adenosine monophosphate (AMP) by converting inosine monophosphate (IMP) to ADS through a GTP-dependent reaction with l-aspartate. Despite its importance, Mtb ADSS remains poorly characterized at the biochemical level. In this study, we report the expression, purification, and enzymatic characterization of recombinant Mtb ADSS. To overcome the challenge of the enzyme being predominantly expressed as inclusion bodies in Escherichia coli, we established both protein refolding and chaperone-assisted expression strategies to obtain soluble, catalytically active protein. Using complementary spectrophotometric, colorimetric, and fluorescence-based assays, we determined steady-state kinetic parameters and confirmed robust ADSS activity consistent with Michaelis-Menten behaviour. Furthermore, we developed scalable, nonradioactive assays compatible with high-throughput screening (HTS), enabling the quantitative monitoring of ADSS activity via GTP hydrolysis and phosphate release. As a proof of concept, the MESG assay successfully detected inhibition of Mtb ADSS by the previously reported ADSS inhibitor Aurodox, demonstrating its utility for inhibitor characterization and screening. Collectively, these results provide the first comprehensive biochemical framework for studying Mtb ADSS and establish a foundation for structure-guided inhibitor discovery targeting purine biosynthesis as a novel antitubercular strategy.
Vigyasa Singh, Ran Zhang, Ke Chen et al.· Biochimica et Biophysica Act...· 0 citations