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Patra, J.

Publications and source records attributed to Patra, J..

2 recordsLinked to original sources

MOLECULAR INSIGHTS INTO BINDING BEHAVIOUR OF LAMOTRIGINE WITH INITIATION FACTOR 2 PROTEIN: AN INTEGRATED COMPUTATIONAL STUDIES

CONSPECTUSO_ST_ABSAimsC_ST_ABSThe ribosomal protein (r-protein) of bacteria is composed of 2.6 MDa ribonucleoproteins of the 30S and 50S subunits, which are essential elements for protein translation. The translational initiation step is an intensive regulated multi-step reaction in protein biosynthesis. During bacterial protein synthesis, the correct reading frame of the mRNA defines when the initiator fMet-tRNAiMet binds to the start codon AUG at the P-site of the 30S subunit. The formation of the P-site of the 30S subunit initiation complex (30S-IC) is governed by three ubiquitous initiation factors (IFs) such as IF1, IF2, and IF3. IF2 protein is an essential player that plays during the last stage of the initiation process. Earlier, Stokes and his co-workers studied chemicals probes using 30K diverse drugs that induced cold-sensitive growth inhibition in the bacterium. The assay studies revealed, Lamotrigine (LTG) effectively binds at domain II of IF2 protein. In our research, we took an attempt in identifying promising active residues that could responsible for anti-bacterial bioactivity with help of computational studies. Computational MethodsIn the present study, initially, we performed C- backbone alignment with the retrieved IF2 chain from AlphaFold. Further, we utilized SiteMap and CastP for the identification of plausible active binding sites. Further, we bound LTG with the designated domain(s) of IF2 protein and studied its binding affinity potential with help of adaptive molecular dynamics simulations at atomic levels using Desmond. Key FindingsOur research findings have shown accurate results and we could able to prove the assertion in contrast with the findings of Stokes and his co-workers where the LTG bind at domain II of IF2 protein. The key interacting residue Glu179 was revealed to have strong hydrogen bonding contacts with LTG at the sub-nanomolar range. In addition, we predicted the alternative promising site I Further, we gained in-depth analysis for studying multiple sites, to understand the synergism inhibitory activity. Promisingly, LTG could be able to bound with at Site 1 showing better affinity over the proposed domain II and other predicted sites. The adaptive molecular dynamics studies confirmed the promising active residues SignificanceThe binding site predictions approach provides an insight for further development of anti-bacterial therapeutics that might helpful for bacteria disease management and exhibiting inhibitory activity against various strains.

bioinformatics↗

Molecular Dynamics Simulations Studies On The Effects Of Mutations On The Binding Affinities Between SARS-CoV-2 Spike RBD And Human ACE2

CONSPECTUSThe SARS-CoV-2 viruses had made a great impact on humankind and the world economy. Phylogenetic analysis revealed the newly identified B.1.617.1 and B.1.617.2 lineages possessed with few key mutations predominantly circulating. The signature mutations possessed by these lineages are situated in the RBD motif of S protein. Reports revealed variants L452R, T478K, and E484Q harbours in enhancement with hACE2 binding while P681R situated in furin cleavage site resulting in better transmissibility. To gain a deeper understanding of the impact of these variants (L452R, T478K and E484Q) binding with hACE2, structural dynamics at the interface between S-RBD protein and hACE2 were studied. We performed our dynamics studies with both single mutant complex (L452R, T478K and E484Q) and in the combination of triple mutants (L452R + T478K + E484Q) at 100ns in contrast with the wild type. Interfacial docking interactions and Molecular Mechanics approach exhibited that the spike mutants -L452R, T478K and E484Q harbour with higher binding affinity on hACE2 in contrast with its native spike protein. The presence of interfacial residue, intermolecular contacts such as hydrogen bonding, salt bridge and non-hydrogen bonded interactions might be the reason for its higher binding affinity. Hence the findings from our study unravelled plausible mechanism for the increase in affinities of mutants to hACE2 thus leading to higher transmissibility and infection of emerging variants. Further, the conformational alterations in the course of dynamics at the RBD motif led to enhancement of hACE2 binding and immune escape. These results suggest that the structural changes introduced by these variants enhance the binding affinities of the S protein with the hACE2 that could form the basis to further aid in designing therapeutics that could inhibit at the interface of S protein and hACE2 receptor.

bioinformatics↗