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The summarized amalgam of internal relaxation modulations and external forces like pH, temperature, and solvent conditions determine the protein structure, stability, and function. In a free-energy landscape, although conformers are arranged in vertical hierarchy, there exist several adjacent parallel sets with conformers occupying equivalent energy cleft. Such conformational states are pre-requisites for the functioning of proteins that have oscillating environmental conditions. As these conformational changes have utterly small re-arrangements, nuclear magnetic resonance (NMR) spectroscopy is unique in elucidating the structure–dynamics–stability–function relationships for such conformations. Helicobacter pylori survives and causes gastric cancer at extremely low pH also. However, least is known as to how the genome of the pathogen is protected from reactive oxygen species (ROS) scavenging in the gut at low pH under acidic stress. In the current study, biophysical characteristics of H. pylori DNA binding protein (Hup) have been elucidated at pH 2 using a combination of circular dichroism, fluorescence, NMR spectroscopy, and molecular dynamics simulations. Interestingly, the protein was found to have conserved structural features, differential backbone dynamics, enhanced stability, and DNA binding ability at low pH as well. In summary, the study suggests the partaking of Hup protein even at low pH in DNA protection for maintaining the genome integrity.

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Tailor‐made application of catanionic aggregates as drug delivery vehicle and as templates for organized nano‐assemblies makes them the best alternatives to liposomes and niosomes. Catanionic aggregates formed by using hydrotropic drug as one of the components pave way for the increased bioavailability thorough sustained contact time and release of the charged drug. In the present investigation, the molecular interaction between the anti‐inflammatory hydrotropic drug, diclofenac sodium (DS) with traditional low cost cationic surfactants with varying chain length is studied. A strong structural transition was observed using turbidity, viscosity, dynamic light scattering, zeta potential, 1H‐NMR, AFM, TEM and SANS techniques. The results suggested that spherically/elliptical shaped micellar aggregates are converted into vesicles through intermediate cylindrical/wormlike aggregates. We have characterized (size and shape) the drug‐surfactant system based on the concentration of the drug, and alkyl chain length of cationic surfactants. The drug loaded vesicles were tested at physiological temperature and were found to stable even at high loading. Due to low cost and high stability, present system could be used as low cost drug delivery vehicle.