Abstract
We computed molecular dynamics (MD) simulation of the enzymatic portion of the cholera toxin A-1 polypeptide (CTA1) in its complex form with the adenosine ribosyl factor (ARF) 6 at temperatures of 283 and 323 K. From total energy analysis it was observed that the toxin in both the forms were stable thermodynamically. However CTA1 in complex with ARF6 was 72% more stable than its counterpart CTA1 in free form. This illustrates that ARF6 act as a source of stability for CTA1. These results were also confirmed by root mean square deviations (RMSD) investigations. The C-α root mean square fluctuation (RMSF) examinations revealed that there are a number of residues inside CTA1, which can be used as drug target. Thus, this studies provides a path for designing and synthesizing inhibitory drugs in order to dysfunction and inactivate the cholera toxin inside the human body. The variations in the values of the radius of gyration and hydrogen bonding proved that protein unfolding and refolding were normal routine phenomena in its structure at both the temperatures. Solvent accessible surface area study showed the hydrophilic nature and due to this property, it could be easily carried in aerosols and used as a one of the devastating biological toxin. The structural identification (STRIDE) of protein algorithm was successfully used to determine the partially disordered secondary structure of CTA1. On account of this partially disordered secondary structure, it can easily deceive the proteolytic enzymes of endoplasmic reticulum of the host cells.
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Badshah, S.L., Naeem, A. Computational Simulation of Conjugated Cholera Toxin Protein. Mol. Genet. Microbiol. Virol. 36 (Suppl 1), S13–S22 (2021). https://doi.org/10.3103/S0891416821050049
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DOI: https://doi.org/10.3103/S0891416821050049