Prismane protein

II, Historical Discovery of Prismane Protein (Now Termed Fepr)... 

Subsequent studies provided a wealth of information that appeared to support the hypothesis that the Fepr protein was a genuine [6Fe-6S]-containing protein. In a biochemical study (10) the elemental analysis was meticulously repeated, and, based on an assumed molecular mass of 52 kDa, the prismane protein was found to contain 6.3 Fe atoms, averaged over as many as nine different preparations. Again, no other metals than Fe were detected, suggesting that all... 

MCD results more or less confirmed the conclusions drawn from previous EPR data (27). The shapes of the MCD spectra of the putative prismane protein in the 3+, 4+, and 5+ states had not been observed for any Fe-S protein. This was not surprising, since every single type of Fe-S cluster is considered to exhibit a unique MCD spectrum. Magnetization data confirmed the S = ground state of the 5-1- state, as well as the S = 4 ground state of the 4+ state. Unexpectedly, in addition to the S = 4 contribution, a considerable diamagnetic contribution was observed for the 4-1- state. The nature of the diamagnetic contribution was not understood a physical spin mixture was considered to be a possible explanation. 

Resonance Raman studies on the putative prismane protein would provide other important information. In the frequency region of 200-430 cm the putative prismane protein showed bands that at first sight seemed to be typical for Fe-S clusters, but at a closer look appeared to be broader than those observed in basic Fe-S proteins. Also, the resonance frequencies were slightly different from known Fe-S clusters, and it was contended that A prismane-type [6Fe-6S] core is clearly an excellent candidate in light of the available analytical and biophysical data [28]. 

Crystallographic data (.continued) for transition metal tetrafluorides, 27 98 for transition metal trifluorides, 27 92 Crystallographic disorder, nitrosyl groups, 34 304-305 Crystallography fuscoredoxin, 47 380 prismane protein, 47 232-233 Rieske and Rieske-type proteins, 47 92-109 Crystal radii, of various ions, 2 7 Crystals, 39 402 Crystal structure actinide metals, 31 36 copper-cobalt supetoxide dismutases, 45 ... 

C. pasteurianum ferredoxin, 38 85, 87 4Fe-4S] cluster, 38 358 fuscoredoxin, 47 380 methane monooxygenase, 43 383-384 "prismane protein, 47 230-231, 246 Rieske and Rieske-type proteins, 47 119-121... 

The finding that the prismane protein does not contain a prismane cluster... 

Figure 5 A sketch of the structure of the hybrid cluster in the prismane protein. The approximate core structure is [4Fe-2S-20]. Cys406 carries a persulfido sulfur. X is an unidentified bridge of low occupancy in the crystal structure.

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