Molecular Dynamics Simulation Insights into Hydrogen Bonding-Mediated Conformational Changes Topoisomerase-IB

Topoisomerase-IB changes the topological state of DNA during central dogma by the formation of intermediate bond in between active amino acid and DNA strand. How the hydrogen bonding provides hooks restriction during the topological change and gives the conformational change. This study employs a 200 ns Molecular Dynamics (MD) simulation to analyze the conformational changes of Topo-IB resulting from artificially created intermediate bonds. Specifically, the study focuses on hydrogen bonding interactions between Tyrosine at position Y509 in the protein and Thymine at DT561 in the DNA. The investigation reveals that these artificial intermediate bonds act as temporary hooks, stabilizing the complex's structure, and driving significant conformational changes. The analysis of Root Mean Square Deviation (RMSD) and Root Mean Square Fluctuation (RMSF) values underscores the dynamic nature of the complex, with artificial intermediate bonds playing a pivotal role.