Deutsch
 
Hilfe Datenschutzhinweis Impressum
  DetailsucheBrowse

Datensatz

DATENSATZ AKTIONENEXPORT

Freigegeben

Zeitschriftenartikel

Structure and Mechanism of the Diiron Benzoyl-Coenzyme A Epoxidase BoxB

MPG-Autoren
/persons/resource/persons137943

Weinert,  Tobias
Department of Molecular Membrane Biology, Max Planck Institute of Biophysics, Max Planck Society;

/persons/resource/persons137633

Demmer,  Ulrike
Department of Molecular Membrane Biology, Max Planck Institute of Biophysics, Max Planck Society;

/persons/resource/persons137604

Bill,  Eckhard
Research Department Wieghardt, Max Planck Institute for Bioinorganic Chemistry, Max Planck Society;

/persons/resource/persons137648

Ermler,  Ulrich
Department of Molecular Membrane Biology, Max Planck Institute of Biophysics, Max Planck Society;

Externe Ressourcen
Es sind keine externen Ressourcen hinterlegt
Volltexte (beschränkter Zugriff)
Für Ihren IP-Bereich sind aktuell keine Volltexte freigegeben.
Volltexte (frei zugänglich)
Es sind keine frei zugänglichen Volltexte in PuRe verfügbar
Ergänzendes Material (frei zugänglich)
Es sind keine frei zugänglichen Ergänzenden Materialien verfügbar
Zitation

Rather, L. J., Weinert, T., Demmer, U., Bill, E., Ismail, W., Fuchs, G., et al. (2011). Structure and Mechanism of the Diiron Benzoyl-Coenzyme A Epoxidase BoxB. The Journal of Biological Chemistry, 286(33), 29241-29248. doi:10.1074/jbc.M111.236893.


Zitierlink: https://hdl.handle.net/11858/00-001M-0000-0024-D5DC-9
Zusammenfassung
The coenzyme A (CoA)-dependent aerobic benzoate metabolic pathway uses an unprecedented chemical strategy to overcome the high aromatic resonance energy by forming the nonaromatic 2,3-epoxybenzoyl-CoA. The crucial dearomatizing reaction is catalyzed by three enzymes, BoxABC, where BoxA is an NADPH-dependent reductase, BoxB is a benzoyl-CoA 2,3-epoxidase, and BoxC is an epoxide ring hydrolase. We characterized the key enzyme BoxB from Azoarcus evansii by structural and Mössbauer spectroscopic methods as a new member of class I diiron enzymes. Several family members were structurally studied with respect to the diiron center architecture, but no structure of an intact diiron enzyme with its natural substrate has been reported. X-ray structures between 1.9 and 2.5Å resolution were determined for BoxB in the diferric state and with bound substrate benzoyl-CoA in the reduced state. The substrate-bound reduced state is distinguished from the diferric state by increased iron-ligand distances and the absence of directly bridging groups between them. The position of benzoyl-CoA inside a 20Å long channel and the position of the phenyl ring relative to the diiron center are accurately defined. The C2 and C3 atoms of the phenyl ring are closer to one of the irons. Therefore, one oxygen of activated O2 must be ligated predominantly to this proximate iron to be in a geometrically suitable position to attack the phenyl ring. Consistent with the observed iron/phenyl geometry, BoxB stereoselectively should form the 2S,3R-epoxide. We postulate a reaction cycle that allows a charge delocalization because of the phenyl ring and the electron-withdrawing CoA thioester.