Hydrogen-deuterium exchange in heavy meromyosin

Abstract

The exchange of peptide hydrogens with deuterium was followed by measuring the decrease of the amide II band at 1542 cm⁻¹ for heavy meromyosin.

Heavy meromyosin contains a relatively large number of slowly exchanging peptide hydrogens which decreases with increasing pH in the pH range 5.5–10.8.

The mechanism of the hydrogen isotope exchange between protein and solvent water is described in terms of HVIDT's model, where rapid equilibrium between a closed and an open molecular conformation is assumed and where only the open form is expected to exchange.