Marion D, Guerlesquin F
Laboratory of Chemical Physics, N.I.D.D.K., Bethesda, MD 20892.
Biochem Biophys Res Commun. 1989 Mar 15;159(2):592-8. doi: 10.1016/0006-291x(89)90035-1.
Desulfovibrio ferredoxins are small proteins involved in biological oxido-reduction reactions and contain either one or two (4Fe-4S) clusters. The conformation of D. desulfuricans Norway ferredoxin I in solution was studied by two-dimensional NMR and various conformational parameters (n.O.e. and J-coupling) indicate the presence of an alpha-helix involving residues 41 to 50. These data confirm an earlier proposal (Fukuyama et al, J. Mol. Biol. 199, 183 (1988] in which the space of the missing cluster in monocluster ferredoxins is occupied by an alpha-helix. The evolutionary relevance of this result is discussed in view of published sequences and structures of related ferredoxins.
