Iron superoxide dismutase

FIGURE 5.11 EPR of an S = 5/2 system with pronounced rhombicity. The X-band spectra (V = 9.31 GHz) are from high-spin FeIH in Escherichia coli iron superoxide dismutase. The observed effective g-values correspond to T = 0.24 in the S = 5/2 rhombogram. 

M.E. Schinia, L. Maffey, D. Barra, F. Bossa, K. Puget, and A.M. Michelson, The primary structure of iron superoxide dismutase from Escherichia coli. FEBS Lett. 221, 87-90 (1987). 

D. Ringe, G.A. Petsko, F. Yamakura, K. Suzuki, and D. Ohmori, Structure of iron superoxide dismutase from Pseudomonas ovalis at 2.9. ANG. resolution. Proc. Natl. Acad. Sci. U.SA. 80, 3879-3883 (1983). 

A. Carlioz, M.L. Ludwig, W.C. Stallings, J.A. Fee, H.M. Steinman, and D. Touati, Iron superoxide dismutase. Nucleotide sequence of the gene from Escherichia coli K12 and correlations with crystal structures. J. Biol. Chem. 263, 1555-1562 (1988). 

B.L. Stoddard, P.L. Howell, D. Ringe, and G.A. Petsko, The 2.1. ANG. resolution structure of iron superoxide dismutase from Pseudomonas ovalis. Biochemisry. 29, 8885-8893 (1990). 

M.L. Ludwig, A.L. Metzger, K.A. Pattridge, and W.C. Stallings, The structure of iron superoxide dismutase from Pseudomonas ovalis complexed with the inhibitor azide. J. Mol. Biol. 219, 335-358 (1991). 

M.S. Lah, M.M. Dixon, K.A. Pattridge, W.C. Stallings, J.A. Fee, and M.L. Ludwig, Structure-function in Escherichia coli iron superoxide dismutase comparisons with the manganese enzyme from Thermus thermophilus. Biochemistry. 34, 1646-1660 (1995). 

Dos Santos WG, Pacheco I, Liu MY, et al. 2000. Purification and characterization of an iron superoxide dismutase and a catalase from the sulfate-reducing bacterium Desulfovibrio gigas. J Bacteriol 182 796-804. 

A representative sampling of non-heme iron proteins is presented in Fig. 3. Evident from this atlas is the diversity of structural folds exhibited by non-heme iron proteins it may be safely concluded that there is no unique structural motif associated with non-heme iron proteins in general, or even for specific types of non-heme iron centers. Protein folds may be generally classified into several categories (i.e., all a, parallel a/)3, or antiparallel /8) on the basis of the types and interactions of secondary structures (a helix and sheet) present (Richardson, 1981). Non-heme iron proteins are found in all three classes (all a myohemerythrin, ribonucleotide reductase, and photosynthetic reaction center parallel a/)8 iron superoxide dismutase, lactoferrin, and aconitase antiparallel )3 protocatechuate dioxygenase, rubredoxins, and ferredoxins). This structural diversity is another reflection of the wide variety of functional roles exhibited by non-heme iron centers. 

Iron-containing superoxide dismutases are present in many species of bacteria (Hassan and Fridovitch, 1978). These nonheme iron proteins have a characteristic set of EPR lines split about g = 4.2 in the ferric state, arising from the middle Kramers doublet of a rhombic high-spin site. Ferrous iron superoxide dismutase forms an S = I complex with NO that resembles the lipoxygenase-NO adduct by EPR criteria (I. Fridovich, T. Kirby, and J. C. Salerno, (1978) unpublished observations). 

Figure 16-22 (A) Structure of the active site of iron superoxide dismutase from E. coli. From Carlioz et al m Courtesy of M. Ludwig. (B) Interpretive drawing illustrating the single-electron transfer from a superoxide molecule to the Fe3+ of superoxide dismutase and associated proton uptake. Based on Lah et al.376...

Samson, G., Herbert, S.K., Fork, D.C. and Laudenbach, D.E. 1994. Acclimation of the photosynthetic apparatus to growth irradiance in the mutant strain of Synechococcus lacking iron superoxide dismutase. Plant Physiol. 105, 287-294. 

Nettleton CJ, Bull C, Baldwin TO, Fee JA. (1984). Isolation of the Escherichia coli iron superoxide dismutase gene Evidence that intracellular superoxide concentration does not regulate oxygen-dependent synthesis of the manganese superoxide dismutase. Proc Nat Acad Sci USA 81 4970-4973. 

W. C. Stallings, K.A. Pattridge, R.K. Strong, and M.L. Ludwig. 1984. Manganese and iron superoxide dismutases are structural homologs J. Biol. Chem. 259 10695-10699. (PubMed)... 

Grove LE, Xie J, Yikilmaz E, Miller AF, Brunold TC (2008) Spectroscopic and computational investigation of second-sphere contributions to redox tuning in Escherichia coli iron superoxide dismutase. Inorg Chem 47 3978-3992... 

Soulere, L., Delplace, P., Davioud-Charvet, E., Py, S., Sergheraert, C., Perie, J., Ricard, I., Hoffmann, P., and Dive, D. (2003). Screening of Plasmodium falciparum iron superoxide dismutase inhibitors and accuracy of the SOD-assays. Bioorg. Med. Chem. 11, 4941-4944. 

These are (1) the copper-zinc superoxide dismutases, CuZnSOD, °° ° found in almost all eukaryotic cells and a very few prokaryotes, and (2) the manganese and iron superoxide dismutases, MnSOD and FeSOD, the former found in the mitochondria of eukaryotic cells, and both found in many prokaryotes. Recent studies of bacterial and yeast mutants that were engineered to contain no superoxide dismutases demonstrated that the cells were unusually sensitive... 

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