AMINO-ACID SEQUENCE OF DESULFOREDOXIN, A NEW TYPE OF NON HEME IRON PROTEIN FROM DESULFOVIBRIO-GIGAS

A new type of non heme iron protein called desulforedoxin has been isolated from the sulfate reducing bacterium, Desulfovibrio gigas. The complete amino acid sequence has been established. The 36 amino acid residues of the sequence are aligned with the aid of peptides obtained by cyanogen bromide cleavage and by hydrolysis with a peptidase isolated from Staphylococcus aureus. Desulforedoxin has been described as a non heme iron protein of molecular weight 7,600 with 2 iron atoms linked to eight cysteine residues. In fact, sequence elucidation shows that it consists of a dimer of a peptide containing 36 aminoacids. We do not know whether if each monomer contains 1 iron atom linked to 4 cysteine residues or whether the two iron cross link the two monomers. Additional studies on the elucidation of the structure of this new cluster are presently under study. © 1979.