Premium
Electron transport components of Heliobacterium chlorum investigated by EPR spectroscopy at 9 and 35 GHz
Author(s) -
Brok Martin,
Vasmel Henk,
Horikx Johannes T.G.,
Hoff Arnold J.
Publication year - 1986
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(86)80110-7
Subject(s) - electron paramagnetic resonance , electron transport chain , spectroscopy , chemistry , laser linewidth , electron transfer , electron , acceptor , crystallography , analytical chemistry (journal) , nuclear magnetic resonance , photochemistry , physics , condensed matter physics , optics , quantum mechanics , biochemistry , laser , chromatography
In membrane fragments of Heliobacterium chlorum we have observed by EPR spectroscopy the light‐induced reduction of a ferredoxin type electron acceptor with g y = 1.937 and g z = 1.879 at a midpoint potential E m > −420 mV. A low‐potential ( E m < −620 mV) electron acceptor at g = 2.0038 having a 15 G wide EPR line at 9.2 GHz and 18 G at 35 GHz could also be reduced by photoaccumulation; it is either located in the electron transport chain or on a side path. The linewidth of the primary donor P‐798 shows an anomalous temperature dependence, possibly caused by a change in dimeric structure induced by cooling. A scheme for the proposed electron transport chain is presented.