P. Bertrand et al., EVIDENCE FOR A MAGIC MAGNETIC-CONFIGURATION BETWEEN FMN AND THE [2FE-2S](-CEPACIA() CENTER OF PHTHALATE DIOXYGENASE REDUCTASE OF PSEUDOMONAS), Journal of the American Chemical Society, 117(6), 1995, pp. 1807-1809
The enzyme phthalate dioxygenase reductase of Pseudomonas cepacia cont
ains two prosthetic groups, a flavin mononucleotide, and a [2Fe-2S] ce
nter. Although these centers are separated by only 12 Angstrom accordi
ng to the X-ray crystal structure, no magnetic coupling effects are de
tected on their EPR spectrum in the NADH-reduced state of the enzyme i
n which both centers are paramagnetic. In this paper, we demonstrate t
hat the peculiar arrangement of the prosthetic groups together with th
e location of the reducible iron site gives rise to a ''magic magnetic
configuration'' for which the dipolar interactions cancel.