Complete assignment of the 1H NMR spectrum of the aromatic residues of lysozyme

Abstract

Assignment of the nuclear magnetic resonance (NMR) spectrum of the 59 non-exchangeable protons of the 13 aromatic amino acid residues of lysozyme has been completed using a combination of selective spin decoupling and nuclear Overhauser experiments. The experimental chemical shift data were used to simulate the aromatic region of the NMR spectrum at 300 MHz and at 470 MHz. Excellent agreement with the experimental spectra was obtained and the simulations permitted more accurate chemical shift values and resonance linewidths to be obtained. The current set of assignments is compared with those of the assignments made previously. Evidence for the motional behaviour of the aromatic amino acid side chains is presented.