Details zur Publikation

Referenztyp Zeitschriften
DOI / URL Link
Titel (primär) Reversible biological Birch reduction at an extremely low redox potential
Autor Kung, J.W.; Baumann, S.; von Bergen, M.; Müller, M.; Hagedoorn, P.-L.; Hagen, W.R.; Boll, M.;
Journal / Serie Journal of the American Chemical Society
Erscheinungsjahr 2010
Department PROTEOM;
Band/Volume 132
Heft 28
Sprache englisch;
Abstract The Birch reduction of aromatic rings to cyclohexadiene compounds is widely used in chemical synthesis and requires solvated electrons, the most potent reductants known in organic chemistry. Benzoyl-coenzyme A (CoA) reductases (BCR) are key enzymes in the anaerobic bacterial degradation of aromatic compounds and catalyze an analogous reaction under physiological conditions. Class I BCRs are FeS enzymes and couple the reductive dearomatization of benzoyl-CoA to cyclohexa-1,5-diene-1-carboxyl-CoA (dienoyl-CoA) to a stoichiometric ATP hydrolysis. Here, we report on a tungsten-containing class II BCR from Geobacter metallireducens that catalyzed the fully reversible, ATP-independent dearomatization of benzoyl-CoA to dienoyl-CoA. BCR additionally catalyzed the disproportionation of dienoyl-CoA to benzoyl-CoA/monoenoyl-CoA and the four- and six-electron reduction of benzoyl-CoA in the presence of a reduced low-potential bridged 2,2'-bipyridyl redox dye. Reversible redox titration experiments in the presence of this redox dye revealed a midpoint potential of E0'= -622 mV for the benzoyl-CoA/dienoyl-CoA couple, which is far below the values of other known reversible substrate/product redox couples in enzymology. This work demonstrates the efficiency of reversible metalloenzyme catalysis, which in chemical synthesis can only be achieved under essentially irreversible conditions.
ID 10219
dauerhafte UFZ-Verlinkung
Kung, J.W., Baumann, S., von Bergen, M., Müller, M., Hagedoorn, P.-L., Hagen, W.R., Boll, M. (2010):
Reversible biological Birch reduction at an extremely low redox potential
J. Am. Chem. Soc. 132 (28), 9850 - 9856