Crystallographic analysis of the intact metal centres [3Fe-4S](1+/0) and [4Fe-4S](2+/1+) in a Zn(2+) -containing ferredoxin.
Detailed structural models of di-cluster seven-iron ferredoxins constitute a valuable resource for folding and stability studies relating the metal cofactors' role in protein stability. The here reported, hemihedric twinned crystal structure at 2.0 A resolution from Acidianus ambivalens ferredoxin, shows an integral 103 residues, physiologically relevant native form composed by a N-terminal extension comprising a His/Asp Zn(2+) site and the ferredoxin (betaalphabeta)(2) core, which harbours intact clusters I and II, a [3Fe-4S](1+/0) and a [4Fe-4S](2+/1+) centres. This is in contrast with the previously available ferredoxin structure from Sulfolofus tokodai, which was obtained from an artificial oxidative conversion with two [3Fe-4S](1+/0) centres and poor definition around cluster II.
Frazão
Carlos
C
Instituto Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av da República, Oeiras, Portugal. frazao@itqb.unl.pt
Aragão
David
D
Coelho
Ricardo
R
Leal
Sónia S
SS
Gomes
Cláudio M
CM
Teixeira
Miguel
M
Carrondo
Maria Arménia
MA
D041541:Acidianus / Q000737:chemistry*; D019843:Archaeal Proteins / Q000737:chemistry*; D018360:Crystallography, X-Ray; D005288:Ferredoxins / Q000737:chemistry*; D007501:Iron / Q000737:chemistry; D008670:Metals / Q000737:chemistry*; D008958:Models, Molecular; D055672:Static Electricity; D013455:Sulfur / Q000737:chemistry; D015032:Zinc / Q000737:chemistry
D019843:Archaeal Proteins; D005288:Ferredoxins; D008670:Metals; D013455:Sulfur; D007501:Iron; D015032:Zinc