Download MendeleyCrystal structure of photolysed carbonmonoxy-myoglobin.
Schlichting, I., Berendzen, J., Phillips Jr., G.N., Sweet, R.M.(1994) Nature 371: 808-812
- PubMed: 7935843
- DOI: https://doi.org/10.1038/371808a0
- Primary Citation of Related Structures:
1ABS - PubMed Abstract:
Myoglobin is a globular haem protein that reversibly binds ligands such as O2 and CO. Single photons of visible light can break the covalent bond between CO and the haem iron in carbon-monoxy-myoglobin (MbCO) and thus form an unstable intermediate, Mb*CO, with the CO inside the protein. The ensuing rebinding process has been extensively studied as a model for the interplay of dynamics, structure and function in protein reactions. We have used X-ray crystallography at liquid-helium temperatures to determine the structure of Mb*CO to a resolution of 1.5 A. The photodissociated CO lies on top of the haem pyrrole ring C. Comparison with the CO-bound and unligated myoglobin structures reveals that on photodissociation of the CO, the haem 'domes', the iron moves partially out of the haem plane, the iron-proximal histidine bonds is compressed, the F helix is strained and the distal histidine swings towards the outside of the ligand-binding pocket.
Organizational Affiliation:
Department of Biophysics, Max Planck Institute for Medical Research, Heidelberg, Germany.
