Proton magnetic resonance study of ferredoxin from Clostridium pasteurianum.
Magnetic susceptibilities of both reduced and oxidized ferredoxin from Clostridium pasteurianum were obtained in solution. Whereas the reduced form exhibits a Curie law behavior, the magnetic susceptibility of oxidized ferredoxin in fact increases with temperature and suggests extensive antiferromagnetic exchange coupling between the component iron atoms. Contact-shifted resonances are observed for both forms of ferredoxin that are attributed to the beta-CH(2) protons of the eight cysteine residues. A model based on these results is presented.
D003013:Clostridium; D003545:Cysteine; D005288:Ferredoxins / Q000032:analysis*; D007501:Iron / Q000032:analysis; D009682:Magnetic Resonance Spectroscopy; D008961:Models, Structural; D012996:Solutions; D013696:Temperature
D005288:Ferredoxins; D012996:Solutions; D007501:Iron; D003545:Cysteine