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Biology subjects

Meena, V. K.

Publications and source records attributed to Meena, V. K..

2 recordsLinked to original sources

Serotype-Specific Detection of Non-Structural Protein 1 from Dengue Viruses by Surface-Enhanced Raman Spectroscopy: An Enhanced Precision Diagnosis

Dengue disease exhibits diverse clinical manifestations in patients when infected by its different serotypes. Early and accurate detection of dengue virus (DENV) infections, particularly distinguishing between serotypes is crucial for effective patient management and sporadic outbreak control. Surface-Enhanced Raman Spectroscopy (SERS) offers advantages of high sensitivity, rapid acquisition, rapid analysis, minimal sample and preparation requirements. In this study, we present a simple and reproducible approach for serotype-specific detection of non-structural protein 1 (NS1) utilizing SERS on an aluminium based substrate. Leveraging specific vibrational signatures of NS1 protein from DENV serotypes, we demonstrated the potential of SERS to discriminate between NS1 proteins across DENV serotypes and also the amino acid residue variations that exist among them from different biological samples. Study demonstrates the SERS based detection of NS1 in the current in-vitro setting has sensitivity and specificity comparable to ELISA assays with limit of detection (LOD) reaching to 1ng/mL. However, the application of nanomaterials-based SERS substrate has potential to further enhance the LOD enabling detection even at lower concentrations. This approach holds promise for advancing our capacity to rapidly diagnose serotypic DENV infection in samples, studying pathogenesis and improving strategies for disease management and control.

microbiology↗

DZNep-induced single point mutation (M236I) in poxviral 2'-O-methyltransferase enhances mRNA stability and translation efficiency

Poxviruses encode two highly conserved S-adenosylmethionine (SAM)-dependent methyltransferases for mRNA capping. While D1L facilitates translation via cap-0 formation, the role of VP39-mediated cap-1 modification has been canonically restricted to shield viral mRNA from cytoplasmic pattern-recognition receptors (PRRs). Here, we uncover a novel function of VP39 by demonstrating that prolonged exposure to the SAM cycle inhibitor DZNep selected a virus escape mutant harbouring a point mutation (M236I) in VP39. VP39_mut bypasses S-adenosylhomocysteine (SAH)-mediated feedback inhibition, enhancing 2-O-methylation of viral transcripts and promoting their association with active translation machinery. Consequently, VP39_mut significantly improves viral protein translation, replicative fitness, and yields across species. Notably, VP39_mut-capped in vitro transcribed (IVT) mRNA exhibited [~]2.7-fold higher protein expression compared to VP39_wt, the standard tool for IVT applications. These findings reveal a unique resistance mechanism and provide critical insights into poxvirus mRNA biology while underscoring the potential of optimized VP39 for advancing mRNA-based therapeutics and vaccine production.

microbiology↗