Early heteronuclear NMR studies with rabbit liver metallothionein MT2

The NMR investigation of rabbit metallothionein MT2 in the group of Professor Kurt Wüthrich during the period 1983‐88 is discussed, with particular emphasis on the early parts of the project. The nature of the protein is presented first, highlighting the central importance of the two metal clusters and the 20 cystein residues. The NMR sequence‐specific assignment process is then described as it was applied to metallothionein, emphasizing the role of multiplet analysis in the phase‐sensitive DQF‐COSY multiplet patterns. The heteronuclear magnetic resonance experiments used to link specific 113 Cd ions in the metal clusters to assigned cysteinyl H β protons are discussed, and the results obtained from these are compared with the metal–cysteinyl linkages found in the crystal structure of rat metallothionein. Copyright © 2003 John Wiley & Sons, Ltd.