A Study of Protein Secondary Structure Hydrogen Bonds under Oxidizing Conditions

Molecular simulations show that hydrogen bond energies are stable between oxidized and unoxidized variants of the same protein, and that, consequentially, the secondary-structure elements are stable. Whilst there is no change in the energy of hydrogen bonds, it is shown that oxidation increases the number of hydrogen bonds between the oxidized histone octamer and its solvation layer. This analysis shows that GSNO-driven oxidation influences the tertiary structure of a protein by modulating hydrogen bond structure, rather than hydrogen bond energies. The active molecule derived from GSNO is nitric oxide (NO), which is an important effector molecule in the redox-signalling pathway. We believe that this model of hydrogen bond structure modulation, rather than hydrogen bond energy, plays an important role in the redox-signalling pathway, where GSNO/NO are the effector molecules.