Abstract
Mutants of the adrenal ferredoxin (adrenodoxin) have been expressed in E. coli in order to improve the understanding of its structure and function. Replacement of the ligands to the /2Fe-2S/ center, C46, C52, C55 and C92, by serine, histidine or aspartic acid lead to apoproteins not incorporating the iron-sulfur cluster, whereas C95S forms a functionally active holoprotein. C-termmal deletions up to amino acid 109 affect the conformation around the iron-sulfur cluster in adrenodoxin and the interaction with CYP11A1 and CYP11B1, but not with adrenodoxin reductase. The presence of P108 is necessary for incorporation of the /2Fe-2S/ cluster and obviously for correct folding of adrenodoxin.