Oxidation of deoxy myoglobin by [Fe(CN) 6] 3
The ability of myoglobin (Mb) to reversibly bind O 2 and other ligands has been well characterized. Mb also participates with a variety of redox metals to form metmyoglobin ( metMb). By using an anaerobic stopped-flow device we have measured outer-sphere oxidation by [Fe(CN) 6] 3− of native sperm wh...
Saved in:
Published in | Journal of inorganic biochemistry Vol. 75; no. 4; pp. 241 - 244 |
---|---|
Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
United States
Elsevier Inc
15.07.1999
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | The ability of myoglobin (Mb) to reversibly bind O
2 and other ligands has been well characterized. Mb also participates with a variety of redox metals to form metmyoglobin (
metMb). By using an anaerobic stopped-flow device we have measured outer-sphere oxidation by [Fe(CN)
6]
3− of native sperm whale myoglobin, recombinant wild-type Mb, and a series of mutant Mb proteins in which the distal His-64 was changed to Gly, Phe, Leu or Val. Second-order rate constants for oxidation of mutant proteins are 10–15 times greater than for recombinant or native (
k
ox ~ 10
6 M
− s
−). We attribute the reduced rate of oxidation of wild-type protein to a higher reorganization energy imposed by the presence of the unique water/His-64/heme interaction, which is absent in the mutant proteins. |
---|---|
Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0162-0134 1873-3344 |
DOI: | 10.1016/S0162-0134(99)00093-8 |