Crystal structure of a distal site double mutant of sperm whale myoglobin at 1.6 A resolution.Rizzi, M., Bolognesi, M., Coda, A., Cutruzzola, F., Allocatelli, C.T., Brancaccio, A., Brunori, M.
(1993) FEBS Lett 320: 13-16
- PubMed: 8462669
- DOI: https://doi.org/10.1016/0014-5793(93)81647-i
- Primary Citation of Related Structures:
- PubMed Abstract:
The three-dimensional structure of sperm whale myoglobin His64(E7)-->Val,Thr67(E10)-->Arg double mutant has been studied by X-ray crystallography at 1.6 A resolution, and refined to a crystallographic R-factor of 0.197. The Arg67(E10) side chain is extended in the direction of the ligand binding site, and its NH1 atom is at a distance of 3.11 A from the NH1 atom of Arg45(CD3), which is also pointing towards the distal site. Both are kept in this position by hydrogen bonding and electrostatic interactions with a solvent sulfate ion, located amongst the two, on the protein surface. No liganded water molecule is present at the sixth coordination position of the Fe(III) heme.
Dipartimento di Genetica e Microbiologia, Università di Pavia, Italy.