| Abstract: | The yield of the triplet state in reaction centers of Rhodopseudomonas sphaeroides is dependent on the strength of an applied magnetic field. Reaction centers of the wild type that lack a functional iron complexed to the primary acceptor ubiquinone show a dependence similar to that of reaction centers of the mutant R-26 in which the iron-ubiquinone complex is intact. Apparently, the iron of the iron-ubiquinone complex is not essential to the effect, but it does exert an influence on its extent. Inchromatophores, the effect is about 2-fold decreased; the value of the magnetic field at which half the effect is found is about 500 G, in contrast to this value for reaction centers, which is 50--100 G. The magnetodependence of the triplet yield is discussed in terms of the Chemically Induced Dynamic Electron Polarization mechanism (CIDEP). |
