Structural differences between [2Fe-2S] clusters in spinach ferredoxin and in the "red paramagnetic protein" from Clostridium pasteurianum. A resonance Raman study.
The [2Fe-2S] ferredoxin ("Red paramagnetic protein", RPP) from C. pasteurianum has been found to be composed of two identical subunits of 10,000 +/- 2 000 daltons, each containing a [2Fe-2S] cluster. Resonance Raman (RR) spectra of RPP have been obtained at 23 degrees K, and compared to those of spinach ferredoxin (Sp Fd). Ten modes of the [2Fe-2S] chromophore were observed in the 100-450 cm-1 range. Assignments of non fundamental modes in the 500-900 cm-1 range allowed correlations between fundamental stretching modes of RPP and Sp Fd. Although assuming a [2Fe-2S] structure, the chromophore of RPP differs from that of Sp Fd by its conformation and by a slight weakening of Fe-S bonds, involving both the inorganic core and the cysteine ligands.
D003013:Clostridium / Q000032:analysis*; D004591:Electrophoresis, Polyacrylamide Gel; D005288:Ferredoxins; D007506:Iron-Sulfur Proteins / Q000032:analysis*; D046911:Macromolecular Substances; D008667:Metalloproteins / Q000032:analysis*; D008970:Molecular Weight; D010944:Plants / Q000032:analysis*; D011487:Protein Conformation; D013053:Spectrophotometry; D013059:Spectrum Analysis, Raman; D013329:Structure-Activity Relationship
D005288:Ferredoxins; D007506:Iron-Sulfur Proteins; D046911:Macromolecular Substances; D008667:Metalloproteins