Primary structure of ferredoxin from bovine kidney mitochondria.

Kidney mitochondrial ferredoxin (renodoxin) is a component of the cytochrome P-450-dependent enzymatic system whose main function is the hydroxylation of vitamin D3 in the 1alpha- and 24-positions. The complete amino acid sequence of renodoxin was determined by protein chemistry and mass spectrometry. The mature renodoxin has 128 amino acid residues. The N- and C-terminal regions of renodoxin are subject to proteolytic modification, this being the origin of heterogeneous molecular mass (from 14,200 to 12,400 kD) of purified protein preparations. The antigenic structure of renodoxin was studied using antibodies to peptide fragments of a homologous protein, adrenodoxin.