A mixed valent form of the iron cluster (Fe(II)Fe(III)) in the B2 protein of ribonucleotide reductase has been isolated and characterized. The irons in this state of the protein are ferromagnetically coupled as indicated by the observation of a novel S = 9/2 EPR spectrum. This is the first ferromagnetically coupled Fe(II)Fe(III) cluster reported for a protein and the first observation of the mixed valence form of ribonucleotide reductase.
|Original language||English (US)|
|Number of pages||6|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Apr 30 1991|
Bibliographical noteFunding Information:
This work was supported by grants from the National Institute of Health, GM-12996 (M. P. H.), and from the National Science Foundation, DMB-8314935, DMB-8804458 (L. Q.). We thank Professor Joanne Stubbe for providing E. coli strain N6405/pSPS2 used in these experiments.