THE HIGH-POTENTIAL IRON-SULFUR PROTEIN (HIPIP) FROM RHODOFERAX FERMENTANS IS COMPETENT IN PHOTOSYNTHETIC ELECTRON-TRANSFER

The functional role of the High Potential Iron-sulfur Protein (HiPIP) from the photosynthetic bacterium Rhodoferax fermentans was investigated, We demonstrated that the HiPIP increased the rate of light-induced oxygen reduction mediated by the photosynthetic reaction center (RC); this stimulation reached half-saturation at [HiPIP]/[RC] ca, 15. The capability of the HiPIP in delivering electrons to the reaction center of Rhodoferax fermentans was demonstrated through kinetic spectrophotometry of cytochrome c-556 oxidation in the presence or in the absence of HiPIP, It is concluded that the HiPIP is competent in the photosynthetic electron transfer chain of Rhodoferax fermentans.