Comparison of the NMR and X-Ray Structures of Hirudin

Abstract

The solution structure of hirudin determined by NMR is compared to that of the subsequently determined crystal structure. The well-defined region common to both structures is the core of the N-terminal domain which comprises residues 2–30 and 37–48. The backbone conformation of the two structures is very similar with an atomic rms difference of <1 Å. A number of side chains have essentially identical conformations in the NMR and crystal structures. The majority of side chains, however, are highly surface exposed and disordered both in solution and in the crystal.