| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
JBC, Vol. 251, Issue 18, 5472-5477, Sep, 1976
T. O. Slykhouse and J. A. Fee
Highly purified iron superoxide dismutase was obtained from Escherichia
coli B using a modification of the procedure of Yost and Jridovich (Yost,
F. J., Jr., and Fridovich, I. (1973) J. Biol. Chem. 248, 4905-4908). The
protein contained 1.8 +/- 0.2 atoms of iron per 38,700 g of protein. We
have found that cyanide does not bind to the Fe3+ ion of iron dismutase but
fluoride and azide have moderately large binding constants. Optical and
electron paramagnetic resonance (EPR) measurements suggested that 2
fluoride ions could associate with each iron atom with the first having an
association constant of approximately 520 M-1 and the second with an
estimated value of 24 M-1. Activity measurements yielded an inhibition
constant for fluoride of 30 M-1. At room temperature only one azide binds
to the Fe3+ (K = 760 M-1) and this does not interfere with superoxide
dismutase activity. Upon freezing solutions of iron superoxide dismutase in
the presence of excess azide their color changes from yellow to pink.
Combined EPR and optical titrations with azide suggest the presence of two
binding sites on Fe3+ with only the first being occupied at room
temperature and the second binding azide only upon freezing the solution.
The results suggest that each Fe3+ ion of this superoxide dismutase has two
coordination positions available for interaction with solute molecules but
only one is necessary for catalysis of the superoxide dismutation reaction.
The EPR, optical, and circular dichroism spectra of the native protein and
the various fluoride and azide complexes are presented.
Physical and chemical studies on bacterial superoxide dismutases. Purification and some anion binding properties of the iron-containing protein of Escherichia coli B
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
 |
|
  G. Regelsberger, U. Laaha, D. Dietmann, F. Ruker, A. Canini, M. Grilli-Caiola, P. G. Furtmuller, C. Jakopitsch, G. A. Peschek, and C. Obinger The Iron Superoxide Dismutase from the Filamentous Cyanobacterium Nostoc PCC 7120: LOCALIZATION, OVEREXPRESSION, AND BIOCHEMICAL CHARACTERIZATION J. Biol. Chem., October 22, 2004; 279(43): 44384 - 44393. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. B. Greenleaf and D. N. Silverman Activation of the Proton Transfer Pathway in Catalysis by Iron Superoxide Dismutase J. Biol. Chem., December 13, 2002; 277(51): 49282 - 49286. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Santos, S. Bocquet, A. Puppo, and D. Touati Characterization of an Atypical Superoxide Dismutase from Sinorhizobium meliloti J. Bacteriol., August 1, 1999; 181(15): 4509 - 4516. [Abstract] [Full Text]
|
|
|
|
|
|
M. M. Whittaker and J. W. Whittaker A Glutamate Bridge Is Essential for Dimer Stability and Metal Selectivity in Manganese Superoxide Dismutase J. Biol. Chem., August 28, 1998; 273(35): 22188 - 22193. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. L. Pinto, H. W. Hellinga, and J. P. Caradonna Construction of a catalytically active iron superoxide dismutase by rational protein design PNAS, May 27, 1997; 94(11): 5562 - 5567. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. J. Ramsey, P. J. Hillas, and P. F. Fitzpatrick Characterization of the Active Site Iron in Tyrosine Hydroxylase. REDOX STATES OF THE IRON J. Biol. Chem., October 4, 1996; 271(40): 24395 - 24400. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Molecular and Cellular Proteomics |
| Journal of Lipid Research | ASBMB Today |
