5MBA

BINDING MODE OF AZIDE TO FERRIC APLYSIA LIMACINA MYOGLOBIN. CRYSTALLOGRAPHIC ANALYSIS AT 1.9 ANGSTROMS RESOLUTION

Replaces:  2MBA

Summary for 5MBA

• Entry DOI: 10.2210/pdb5mba/pdb
• Descriptor: MYOGLOBIN, AZIDE ION, PROTOPORPHYRIN IX CONTAINING FE, ... (4 entities in total)
• Functional Keywords: oxygen storage
• Biological source: Aplysia limacina (slug sea hare)
• Total number of polymer chains: 1
• Total formula weight: 16007.94

Authors

Bolognesi, M.,Onesti, S.,Gatti, G.,Coda, A.,Ascenzi, P.,Brunori, M. (deposition date: 1991-01-14, release date: 1992-07-15, Last modification date: 2024-10-23)

Primary citation

Mattevi, A.,Gatti, G.,Coda, A.,Rizzi, M.,Ascenzi, P.,Brunori, M.,Bolognesi, M.
Binding mode of azide to ferric Aplysia limacina myoglobin. Crystallographic analysis at 1.9 A resolution.
J.Mol.Recog., 4:1-6, 1991

PubMed Abstract: The binding mode of azide to the ferric form of Aplysia limacina myoglobin has been studied by X-ray crystallography. The three-dimensional structure of the complex has been refined at 1.9 A resolution to a crystallographic R-factor of 13.9%, including 126 ordered solvent molecules. Azide binds to the heme iron, at the sixth co-ordination position, and is oriented towards the outer part of the distal site crevice. This orientation is stabilized by an ionic interaction with the side-chain of Arg66 (E10) which, from an outer orientation in the 'aquo-met' ligand-free myoglobin, folds back towards the distal site in the presence of the anionic ligand. In the absence of a hydrogen bond donor residue at the distal E7 position in Aplysia limacina myoglobin, a different polar residue, Arg66 at the E10 topological position, has been selected by molecular evolution in order to grant ligand stabilization.

PubMed: 1931125
DOI: 10.1002/jmr.300040102

Experimental method

X-RAY DIFFRACTION (1.9 Å)